WorldWideScience

Sample records for leo vhandu tanel

  1. Faasioni juht Tanel Malk alustas äri garaazhipoes / Tanel Malk ; interv. Marika Tomberg

    Index Scriptorium Estoniae

    Malk, Tanel

    2004-01-01

    Hiiumaa ehitusmaterjalide kaupluse OÜ Faasion juht Tanel Malk ettevõtte arengust, oma juhtimispõhimõtteist ning suurimatest saavutustest ettevõtte eesotsas. Kommenteerivad Agu Kohari ja Jaanus Kosemaa. Lisa: Tanel Malk

  2. Tshuzhoi Tanel Padar / Dmitri Babitshenko

    Index Scriptorium Estoniae

    Babitshenko, Dmitri

    2007-01-01

    Saksamaalt pärit, Eesti ülikoolides filmiteooria ja -ajaloo loenguid pidav ja filmi "Ring tee" valmimist režissöörina juhtinud Dirk Hoyeri mängufilm esilinastub 27. apr. kinos "Sõprus". Praeguseks on film ümber nimetatud "Võõraks", ühes peaosadest astub üles muusik Tanel Padar

  3. Tanel Padar & The Sun veab õhukitarri

    Index Scriptorium Estoniae

    2008-01-01

    Õhukitarri Eesti meistrivõistlustest 19. apr. Tallinnas Rock Cafés (võistluste eestvedajaks on ansambel Tanel Padar & The Sun, kes samas esitleb oma esimest ingliskeelset albumit "Here Comes The Sun")

  4. 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

  5. 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

  6. Tanel Padar & The Sun veab õhukitarri

    Index Scriptorium Estoniae

    2008-01-01

    Õhukitarri Eesti meistrivõistlustest 19. apr. Tallinnas Rock Cafés (võistluste eestvedajaks on ansambel Tanel Padar & The Sun, kes samas esitleb oma esimest ingliskeelset albumit "Here Comes The Sun")

  7. Tanel Padar osaleb dokumentaalfilmis / Verni Leivak

    Index Scriptorium Estoniae

    Leivak, Verni, 1966-

    2001-01-01

    USA plaadi- ja filmitootjafirma "insite" teeb filmi maailma noortest muusikutest "Rock the Planet", kes kommertsile lõivu maksmata hakkama püüavad saada. Üheks tegelaseks on režissöör eales Linton valinud ka Tanel Padari

  8. Tanel Padar osaleb dokumentaalfilmis / Verni Leivak

    Index Scriptorium Estoniae

    Leivak, Verni, 1966-

    2001-01-01

    USA plaadi- ja filmitootjafirma "insite" teeb filmi maailma noortest muusikutest "Rock the Planet", kes kommertsile lõivu maksmata hakkama püüavad saada. Üheks tegelaseks on režissöör eales Linton valinud ka Tanel Padari

  9. Tanel Trööbil hea klapp välispartneritega / Tanel Trööp ; interv. Marika Tomberg

    Index Scriptorium Estoniae

    Trööp, Tanel, 1971-

    2004-01-01

    Reklaamifirma Jaa Disain juht Tanel Trööp oma senisest karjäärist, juhtimismeetoditest, tegevusest ja eesmärkidest ettevõtte eesotsas. Kommenteerivad Taavi Reigam ja Eno Juul. Lisa: Tanel Trööp

  10. Tanel Toom: teen seda, mida armastan / intervjueerinud Kaarel Kressa

    Index Scriptorium Estoniae

    Toom, Tanel, 1982-

    2011-01-01

    Eesti režissöör Tanel Toom oma lühifilmist "Pihtimus", mis kandideeris parima lühifilmi kategoorias Oscarile, oma filmidest ja tulevikuplaanidest, lemmikutest tänavuste Oscari-nominentide hulgas, Oscarile kandideerimise tähtsusest

  11. Tanel Toom: teen seda, mida armastan / intervjueerinud Kaarel Kressa

    Index Scriptorium Estoniae

    Toom, Tanel, 1982-

    2011-01-01

    Eesti režissöör Tanel Toom oma lühifilmist "Pihtimus", mis kandideeris parima lühifilmi kategoorias Oscarile, oma filmidest ja tulevikuplaanidest, lemmikutest tänavuste Oscari-nominentide hulgas, Oscarile kandideerimise tähtsusest

  12. Disainilugu metallis ja tekstiilis / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Tekstiilikunstniku Hilja Kullese juubelinäitus "Õhtu" Eesti Tarbekunsti- ja Disanimuuseumis. Näitus "Roman Tavasti juveelifirma koolimärgid 1923-2010" Tallinna Arhitektuuri- ja Disainigaleriis. Keraamik Leo Rohlini näitus "Nokturn" Hop-galeriis

  13. Disainilugu metallis ja tekstiilis / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Tekstiilikunstniku Hilja Kullese juubelinäitus "Õhtu" Eesti Tarbekunsti- ja Disanimuuseumis. Näitus "Roman Tavasti juveelifirma koolimärgid 1923-2010" Tallinna Arhitektuuri- ja Disainigaleriis. Keraamik Leo Rohlini näitus "Nokturn" Hop-galeriis

  14. Tanel Saare omapärane duett Jüri Järvetiga / Tiiu Laks

    Index Scriptorium Estoniae

    Laks, Tiiu, 1984-

    2010-01-01

    VAT Teatri lavastusest "... viimane lint / Saare esimene lint", kus põimuvad Tanel Saare esitus ja Jüri Järvet vana Krappina ekraanil. Tanel Saar lindistab S. Becketti "Krappi viimase lindi" salvestatud osa, mille kuulamine taaslavastatakse 30 aasta pärast, kui T. Saar ise on juba vana Krappi eas

  15. Leo & Sam”

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Leo and Sam exited and locked the car in a hurry,forgetting to remove the key which was in theignition.Realizing the mistake,Leo asked,“Why don t we get a coat hanger to open it.”“No,that won t work,answered Sam.”People will think we re trying to break in.”Then Leo suggested,“What if we use a pocket knife to cut around the rubber,then stick a finger

  16. Leo II PC

    Data.gov (United States)

    Kansas Data Access and Support Center — LEO II is a second-generation software system developed for use on the PC, which is designed to convert location references accurately between legal descriptions and...

  17. Leo Meyer / Villem Reiman

    Index Scriptorium Estoniae

    Reiman, Villem

    2008-01-01

    Prof. dr. phil. Leo Meyer (03.07.1830-24.05.1910), keeleteadlane, Tartu ja Göttingeni ülikooli ja võrdleva keeleteaduse õppejõud, Eesti Kirjanduse Seltsi kauaaegne esimees ja esimene auliige. Varem ilm.: Eesti Kirjandus, 1910, nr. 9, lk. 389-393

  18. Leo Doyle, master surgeon.

    Science.gov (United States)

    Vellar, I

    2000-10-01

    On 3 March 1953 Leo Doyle died at the Mercy Hospital, Melbourne. The day before he died Leo Doyle had been operating at the Mercy Hospital when he took ill. Doyle's final illness was almost certainly the result of the severe aortic stenosis that had been developing over some years. His death at the relatively young age of 61 ended the career of a man described by Sir Gordon Gordon Taylor as the greatest technical surgeon that he had ever seen. In all likelihood Australian surgery will never see the likes of Doyle, a virtuoso surgeon, again. And yet to many of the surgeons who were Doyle's contemporaries and to those who followed him he remained somewhat of an enigma. Perhaps in some way the description of the great French surgeon Baron Dupuytren may also be applicable to Leo Doyle: known to all, loved by many, understood by few. By all accounts Leo Doyle's surgical repertoire knew no bounds. He operated with equal facility on the central nervous system, the head and neck, in the thorax, abdomen and pelvis and he was more than competent in gynaecology, urology and orthopaedics. In the latter part of his career he became, par excellence, a cancer surgeon. He was, arguably, Australia's first surgical oncologist. No procedure was deemed too complicated or demanding. Like some other superb technicians his judgement at times did not match his technical ability. Doyle was one of the first surgeons in Australia to perform hindquarter amputation and he helped to pioneer the operations of total gastrectomy and oesophagogastrectomy. An avid reader of the surgical literature, he possessed an enormous library which was matched by an equally large collection of surgical instruments. Unlike Devine he published relatively little. He was not a good clinical teacher, preferring to teach by example in the operating theatre. Although interested in music and the visual arts, surgery was his life.

  19. Tanel Toom püsib Oscari-karussellil ja hakkab väntama thrillerit / Tiit Tuumalu

    Index Scriptorium Estoniae

    Tuumalu, Tiit, 1971-

    2010-01-01

    Tanel Toomi uuest mängufilmist "Värav nr. 6", mis valmib Inglismaal tootjastuudios Sentinel Entertainment ja filmi "Pihtimus" pääsemisest poolfinaali Oscari-konkurentsis lühimängufilmi kategoorias

  20. Petróleo

    Directory of Open Access Journals (Sweden)

    Celso Fernando Lucchesi

    1998-08-01

    Full Text Available COM MENOS DE 50 anos de atividade empresarialmente organizada a exploração de petróleo no Brasil encontra-se em fase de mudança com a aprovação, em 1997, da nova legislação do setor de petróleo. Descreve-se neste trabalho o período pré-Petrobras (1858 a 1953 e a exclusividade da Petrobras (1954 a 1997 que resultou no expressivo volume de reservas de petróleo no país, da ordem de 17 bilhões de barris de óleo equivalente no final de 1997. Projetos de produção já iniciados elevarão a produção a mais de 1,5 milhão de barris de óleo por dia no início do novo século. O gás natural crescerá rapidamente sua participação na matriz energética a partir de 1999. Com a instalação da Agência Nacional de Petróleo (ANP inicia-se uma nova fase, sendo esta responsável pela atração de novos investimentos na busca de novas reservas nas bacias sedimentares brasileiras, cujo potencial é ainda significativo. Diversas empresas internacionais deverão estar operando no país no curto prazo, inicialmente associadas à Petrobras. O modelo adotado para as atividades de exploração e produção no país é o de concessão. A atividade no Brasil nesta área dependerá do regime fiscal que vier a ser implantado.THE APPROVAL OF the new Petroleum Law in 1997 proposed a dramatic change in the activities of petroleum exploration in Brazil after almost fifty years of its initial entrepreneurual organization, represented by the creation of Petrobras, in 1953. In this work two important periods are described: the pre-Petrobras period (1858 to 1953 and the period when Petrobras acted alone in the oil business (1954 to 1997. During the last one, significant results were achieved. The amount of reserves reached 17 billion barrels of oil equivalent and were made available to the country at the end of 1997. Production projects already in place or under development will raise Brazilian daily production to levels of 1.5 million barrels of oil per day

  1. Narva narkomaanid jätavad oma lapsed nime ja dokumentideta / Tanel Mazur, Mari Kodres

    Index Scriptorium Estoniae

    Mazur, Tanel, 1971-

    2008-01-01

    Probleemidest, mida tõstatas narkomaanide ja alkohoolikute rehabilitatsiooniga tegeleva MTÜ Sind Ei Jäeta Üksi juht Tatjana Magerova kohtumisel Narvas külaskäigul viibinud presidendi Toomas Hendrik Ilvesega. Vabariigi President Ida-Virumaal 19.-20.11.2008. Ilmunud ka Narva Postiljon 22. nov. lk. 1, autor ainult Tanel Mazur

  2. Narva narkomaanid jätavad oma lapsed nime ja dokumentideta / Tanel Mazur, Mari Kodres

    Index Scriptorium Estoniae

    Mazur, Tanel, 1971-

    2008-01-01

    Probleemidest, mida tõstatas narkomaanide ja alkohoolikute rehabilitatsiooniga tegeleva MTÜ Sind Ei Jäeta Üksi juht Tatjana Magerova kohtumisel Narvas külaskäigul viibinud presidendi Toomas Hendrik Ilvesega. Vabariigi President Ida-Virumaal 19.-20.11.2008. Ilmunud ka Narva Postiljon 22. nov. lk. 1, autor ainult Tanel Mazur

  3. Lunar Exploration Orbiter (LEO)

    Science.gov (United States)

    Jaumann, R.; Spohn, T.; Hiesinger, H.; Jessberger, E. K.; Neukum, G.; Oberst, J.; Helbert, J.; Christensen, U.; Keller, H. U.; Mall, U.; Böhnhardt, H.; Hartogh, P.; Glassmeier, K.-H.; Auster, H.-U.; Moreira, A.; Werner, M.; Pätzold, M.; Palme, H.; Wimmer-Schweingruber, R.; Mandea, M.; Lesur, V.; Häusler, B.; Hördt, A.; Eichentopf, K.; Hauber, E.; Hoffmann, H.; Köhler, U.; Kührt, E.; Michaelis, H.; Pauer, M.; Sohl, F.; Denk, T.; van Gasselt, S.

    2007-08-01

    The Moon is an integral part of the Earth-Moon system, it is a witness to more than 4.5 b. y. of solar system history, and it is the only planetary body except Earth for which we have samples from known locations. The Moon is our closest companion and can easily be reached from Earth at any time, even with a relatively modest financial budget. Consequently, the Moon was the first logical step in the exploration of our solar system before we pursued more distant targets such as Mars and beyond. The vast amount of knowledge gained from the Apollo and other lunar missions of the late 1960's and early 1970's demonstrates how valuable the Moon is for the understanding of our planetary system. Even today, the Moon remains an extremely interesting target scientifically and technologically, as ever since, new data have helped to address some of our questions about the Earth-Moon system, many questions remained. Therefore, returning to the Moon is the critical stepping-stone to further exploring our immediate planetary neighborhood. In this concept study, we present scientific and technological arguments for a national German lunar mission, the Lunar Explorations Orbiter (LEO). Numerous space-faring nations have realized and identified the unique opportunities related to lunar exploration and have planned missions to the Moon within the next few years. Among these missions, LEO will be unique, because it will globally explore the Moon in unprecedented spatial and spectral resolution. LEO will significantly improve our understanding of the lunar surface composition, surface ages, mineralogy, physical properties, interior, thermal history, gravity field, regolith structure, and magnetic field. The Lunar Explorations Orbiter will carry an entire suite of innovative, complementary technologies, including high-resolution camera systems, several spectrometers that cover previously unexplored parts of the electromagnetic spectrum over a broad range of wavelengths, microwave and

  4. Íleo biliar

    OpenAIRE

    Allan Pérez-Baltodano; Marcela Bermúdez-Coto; Madelein Centeno-Rodríguez; William Vargas-Alpízar

    2005-01-01

    El íleo biliar es una entidad clínica difícil de diagnosticar que se produce como resultado de una comunicación anormal entre la vía biliar y el tubo digestivo, con la consiguiente evacuación del cálculo e impactación del mismo distalmente hasta que se presenta como un cuadro de obstrucción intestinal. Reportamos el caso de un paciente de 47 años de edad, sin antecedentes médicos ni quirúrgicos de importancia, que ingresó al servicio de emergencias quirúrgicas con un abdomen agudo, caracteriz...

  5. Íleo biliar

    Directory of Open Access Journals (Sweden)

    Allan Pérez-Baltodano

    2005-01-01

    Full Text Available El íleo biliar es una entidad clínica difícil de diagnosticar que se produce como resultado de una comunicación anormal entre la vía biliar y el tubo digestivo, con la consiguiente evacuación del cálculo e impactación del mismo distalmente hasta que se presenta como un cuadro de obstrucción intestinal. Reportamos el caso de un paciente de 47 años de edad, sin antecedentes médicos ni quirúrgicos de importancia, que ingresó al servicio de emergencias quirúrgicas con un abdomen agudo, caracterizado por dolor en epigastrio e hipocondrio derecho de cinco días de evolución, fiebre y vómitos. El ultrasonido de abdomen reveló una colecistitis aguda. La radiografía simple de abdomen mostró niveles hidroaéreos y una asa fija en el hipocondrio derecho. La laparotomía exploratoria reveló una fístula colecistogástrica asociada a obstrucción intestinal secundaria a un lito biliar enclavado en el íleon terminal. Se le practicó una colecistectomía, enterolitotomía, enterorrafia y reparación de la fístula en un solo tiempo quirúgico. Se realiza una revisión biliográfica de este tema de difícil diagnóstico, con el fin de exponer la controversia que aún existe sobre el manejo quirúrgico del íleo biliar y establecer los diversos criterios de resolución quirúrgica, tanto en uno como en 2 tiempos quirúrgicos.

  6. Jaanus Tamkivi: Sillamäe kirjutas projekti ja sai raha / Tanel Mazur

    Index Scriptorium Estoniae

    Mazur, Tanel, 1971-

    2007-01-01

    Ilmunud ka: Narvskaja Gazeta, 8. okt. 2007, lk. 2. Eesti riigiametnike foorumi raames Narvas andsid pressikonverentsi peaminister Andrus Ansip, siseminister Jüri Pihl, välisminister Rein Lang ja keskkonnaminister Jaanus Tamkivi. Vt. ka: lk. 3: Tanel Mazur. Valitsus otsustas Pärnu-Mõisaküla raudtee üles võtta. Lisa: Raudtee, mis vanima kitsarööpmelise kohal

  7. Jaanus Tamkivi: Sillamäe kirjutas projekti ja sai raha / Tanel Mazur

    Index Scriptorium Estoniae

    Mazur, Tanel, 1971-

    2007-01-01

    Ilmunud ka: Narvskaja Gazeta, 8. okt. 2007, lk. 2. Eesti riigiametnike foorumi raames Narvas andsid pressikonverentsi peaminister Andrus Ansip, siseminister Jüri Pihl, välisminister Rein Lang ja keskkonnaminister Jaanus Tamkivi. Vt. ka: lk. 3: Tanel Mazur. Valitsus otsustas Pärnu-Mõisaküla raudtee üles võtta. Lisa: Raudtee, mis vanima kitsarööpmelise kohal

  8. Tanel Toom: 28selt Oscarit saada oleks vara / intervjueerinud Tiit Tuumalu

    Index Scriptorium Estoniae

    Toom, Tanel, 1982-

    2011-01-01

    Eesti režissööri Tanel Toomi lühifilm "Pihtimus" ("The Confession") kandideeris parima lühifilmi kategoorias Oscarile. Võitis Luke Matheny "God of Love", USA 2010. Noor režissöör räägib oma muljeid Oscarite jagamise tseremooniast. Ära on toodud ka lühike võitjate nimekiri

  9. Wave Optics Based LEO-LEO Radio Occultation Retrieval

    DEFF Research Database (Denmark)

    von Benzon, Hans-Henrik; Høeg, Per

    2016-01-01

    This paper describes the theory for performing retrieval of radio occultations that use probing frequencies in the XK and KM band. Normally radio occultations use frequencies in the L band and GPS satellites are used as the transmitting source and the occultation signals are received by a GPS...... in the signal amplitude caused by atmospheric absorption. The radio wave transmitter is placed on one of these satellites while the receiver is placed on the other LEO satellite. One of the drawbacks of normal GPS based radio occultations is that external information is needed to calculate some...... chain is therefore a wave optics based retrieval chain and it is therefore possible to process measurements that include multipath. In this paper simulated LEO to LEO radio occultations based on 5 different frequencies are used. The 5 frequencies are placed in the XK or KM frequency band. This new wave...

  10. Wave Optics Based LEO-LEO Radio Occultation Retrieval

    DEFF Research Database (Denmark)

    von Benzon, Hans-Henrik; Høeg, Per

    2016-01-01

    in the signal amplitude caused by atmospheric absorption. The radio wave transmitter is placed on one of these satellites while the receiver is placed on the other LEO satellite. One of the drawbacks of normal GPS based radio occultations is that external information is needed to calculate some...... of the atmospheric products such as the correct water vapor content in the atmosphere. These limitations can be overcome when a proper selected range of high frequency waves are used to probe the atmosphere. Probing frequencies close to the absorption line of water vapor have been included, thus allowing...... chain is therefore a wave optics based retrieval chain and it is therefore possible to process measurements that include multipath. In this paper simulated LEO to LEO radio occultations based on 5 different frequencies are used. The 5 frequencies are placed in the XK or KM frequency band. This new wave...

  11. Íleo biliar

    Directory of Open Access Journals (Sweden)

    Allan Pérez-Baltodano

    2005-01-01

    Full Text Available El íleo biliar es una entidad clínica difícil de diagnosticar que se produce como resultado de una comunicación anormal entre la vía biliar y el tubo digestivo, con la consiguiente evacuación del cálculo e impactación del mismo distalmente hasta que se presenta como un cuadro de obstrucción intestinal. Reportamos el caso de un paciente de 47 años de edad, sin antecedentes médicos ni quirúrgicos de importancia, que ingresó al servicio de emergencias quirúrgicas con un abdomen agudo, caracterizado por dolor en epigastrio e hipocondrio derecho de cinco días de evolución, fiebre y vómitos. El ultrasonido de abdomen reveló una colecistitis aguda. La radiografía simple de abdomen mostró niveles hidroaéreos y una asa fija en el hipocondrio derecho. La laparotomía exploratoria reveló una fístula colecistogástrica asociada a obstrucción intestinal secundaria a un lito biliar enclavado en el íleon terminal. Se le practicó una colecistectomía, enterolitotomía, enterorrafia y reparación de la fístula en un solo tiempo quirúgico. Se realiza una revisión biliográfica de este tema de difícil diagnóstico, con el fin de exponer la controversia que aún existe sobre el manejo quirúrgico del íleo biliar y establecer los diversos criterios de resolución quirúrgica, tanto en uno como en 2 tiempos quirúrgicos.Gallstone ileus is a clinical entity of difficult diagnosis; it is the result of an anomalous communication between the biliary tree and the gastrointestinal tract, with the eventual evacuation of the gallstone which becomes impacted in the distal tract where it causes intestinal obstruction. We report the case of a 47-year-old male, without relevant past medical history, who arrived to the emergency room with epigastric and right upper quadrant pain, fever and vomiting. The abdominal ultrasound showed acute cholecystitis. A conventional abdominal film showed air- filled small bowel loops and a fixed loop in the right

  12. Mitochondrial genome of the African lion Panthera leo leo.

    Science.gov (United States)

    Ma, Yue-ping; Wang, Shuo

    2015-01-01

    In this study, the complete mitochondrial genome sequence of the African lion P. leo leo was reported. The total length of the mitogenome was 17,054 bp. It contained the typical mitochondrial structure, including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region; 21 of the tRNA genes folded into typical cloverleaf secondary structure except for tRNASe. The overall composition of the mitogenome was A (32.0%), G (14.5%), C (26.5%) and T (27.0%). The new sequence will provide molecular genetic information for conservation genetics study of this important large carnivore.

  13. Leo Tolstoy the Spiritual Educator

    Science.gov (United States)

    Moulin, Dan

    2008-01-01

    This paper considers the often overlooked religious and educational works of the Russian novelist Leo Tolstoy (1828-1910). After outlining Tolstoy's life, religious and educational views, it is argued that Tolstoy has much to offer spiritual educators today. In particular, it suggests Tolstoy's insistence on the absolute and eternal nature of…

  14. Wave optics-based LEO-LEO radio occultation retrieval

    Science.gov (United States)

    Benzon, Hans-Henrik; Høeg, Per

    2016-06-01

    This paper describes the theory for performing retrieval of radio occultations that use probing frequencies in the XK and KM band. Normally, radio occultations use frequencies in the L band, and GPS satellites are used as the transmitting source, and the occultation signals are received by a GPS receiver on board a Low Earth Orbit (LEO) satellite. The technique is based on the Doppler shift imposed, by the atmosphere, on the signal emitted from the GPS satellite. Two LEO satellites are assumed in the occultations discussed in this paper, and the retrieval is also dependent on the decrease in the signal amplitude caused by atmospheric absorption. The radio wave transmitter is placed on one of these satellites, while the receiver is placed on the other LEO satellite. One of the drawbacks of normal GPS-based radio occultations is that external information is needed to calculate some of the atmospheric products such as the correct water vapor content in the atmosphere. These limitations can be overcome when a proper selected range of high-frequency waves are used to probe the atmosphere. Probing frequencies close to the absorption line of water vapor have been included, thus allowing the retrieval of the water vapor content. Selecting the correct probing frequencies would make it possible to retrieve other information such as the content of ozone. The retrieval is performed through a number of processing steps which are based on the Full Spectrum Inversion (FSI) technique. The retrieval chain is therefore a wave optics-based retrieval chain, and it is therefore possible to process measurements that include multipath. In this paper simulated LEO to LEO radio occultations based on five different frequencies are used. The five frequencies are placed in the XK or KM frequency band. This new wave optics-based retrieval chain is used on a number of examples, and the retrieved atmospheric parameters are compared to the parameters from a global European Centre for Medium

  15. Creation of Leo LT postponed yet again

    Index Scriptorium Estoniae

    2008-01-01

    Valitsusega koos investeerimisfirmat Leo LT loova ettevõtte NDX Energija esindaja Ignas Staskevicius ei välista ka projektist loobumist, kuna lepingute tegemine on jäänud venima. Investeerimisfirma Leo LT ülesandeks on ehitada Leedu uus tuumajaam

  16. The resolved stellar population of Leo A

    NARCIS (Netherlands)

    Tolstoy, E

    1996-01-01

    New observations of the resolved stellar population of the extremely metal-poor Magellanic dwarf irregular galaxy Leo A in Thuan-Gunn r, g, i, and narrowband Ha filters are presented. Using the recent Cepheid variable star distance determination to Leo A by Hoessel et al., we are able to create an a

  17. Mis mõtteid õpetajahariduse strateegia projekt tekitab? / Katrin Irlis, Kaarel Haav, Ene Mägi, Tanel Sits...[jt.

    Index Scriptorium Estoniae

    2008-01-01

    Küsimusele vastavad Mustamäe reaalgümnaasiumi eesti keele õpetaja Katrin Irlis, TTÜ majandusteaduskonna õppejõud Kaarel Haav, TLÜ eri- ja sotsiaalpedagoogika osakonna juhataja Ene Mägi, TLÜ üliõpilane, üliõpilaskondade liidu hariduspoliitika nõunik Tanel Sits, Suure-Jaani gümnaasiumi direktor Peeter Sadam, TLÜ kasvatusteaduste instituudi direktor Rain Mikser ja TÜ üliõpilane, keemiaõpetaja Martin Saar

  18. Ehtekunsti kõrgmäestik Münchenis / Kadri Mälk, Piret Hirv, Tanel Veenre

    Index Scriptorium Estoniae

    Mälk, Kadri, 1958-

    2009-01-01

    Ehtekunsti suurüritusest "Schmuckszene" ("Ehtepaik"). Arnoldsche Art Publishers esitles viit aasta paremaks ehtekunstiraamatuks tituleeritut, nende seas Eestis trükikojas Pakett trükitud raamatut "Just must" (kujundaja Aadam Kaarma, fotod: Tanel Veenre). Darling Publications'i poolt esitletud raamatust "The Compendium Finale of Contemporary Jewellery Makes", kus tutvustatakse kümmet eesti ehtekunstnikku, tekstide autorid on Kadri Mälk, Harry Liivrand ja Tamara Luuk

  19. Ehtekunsti kõrgmäestik Münchenis / Kadri Mälk, Piret Hirv, Tanel Veenre

    Index Scriptorium Estoniae

    Mälk, Kadri, 1958-

    2009-01-01

    Ehtekunsti suurüritusest "Schmuckszene" ("Ehtepaik"). Arnoldsche Art Publishers esitles viit aasta paremaks ehtekunstiraamatuks tituleeritut, nende seas Eestis trükikojas Pakett trükitud raamatut "Just must" (kujundaja Aadam Kaarma, fotod: Tanel Veenre). Darling Publications'i poolt esitletud raamatust "The Compendium Finale of Contemporary Jewellery Makes", kus tutvustatakse kümmet eesti ehtekunstnikku, tekstide autorid on Kadri Mälk, Harry Liivrand ja Tamara Luuk

  20. Optimal trajectories for LEO-to-LEO aeroassisted orbital transfer

    Science.gov (United States)

    Miele, A.; Lee, W. Y.; Mease, K. D.

    This paper considers both classical and minimax problems of optimal control arising in the study of noncoplanar, aeroassisted orbital transfer. The maneuver considered involves the transfer from one planetary orbit to another having different orbital inclination, but the same radius. An example is the LEO-to-LEO transfer of a spacecraft with a prescribed plane change, where LEO denotes low Earth orbit. The basic idea is to employ the hybrid combination of propulsive maneuvers in space and aerodynamic maneuvers in the sensible atmosphere. Hence, this type of flight is also called synergetic space flight. With reference to the atmospheric part of the maneuver, trajectory control is achieved by modulating the lift coefficient (hence, the angle of attack) and the angle of bank. The presence of upper and lower bounds on the lift coefficient is considered. Three different transfer maneuvers are studied. Type 1 involves four impulses and four space plane changes; Type 2 involves three impulses and three space plane changes; and Type 3 involves three impulses and no space plane change. In Type 1, the initial impulse directs the spacecraft away from Earth, and then is followed by an apogee impulse propelling the spacecraft toward Earth; in Types 2 and 3, the initial impulse directs the spacecraft toward Earth. A common element of these maneuvers is that they all include an atmospheric pass, with velocity depletion coupled with plane change. Within the framework of classical optimal control, the following problems are studied: (P1) minimize the energy required for orbital transfer; (P4) maximize the time of flight during the atmospheric portion of the trajectory; (P5) minimize the time integral of the square of the path inclination. Within the framework of minimax optimal control, the following problem is studied: (Q1) minimize the peak heating rate. Numerical solutions for Problems (P1), (P4), (P5), (Q1) are obtained by means of the sequential gradient-restoration algorithm

  1. Leo Tolstoy's theory of sleep.

    Science.gov (United States)

    Vein, Alla A

    2008-03-01

    Throughout his life, Leo Tolstoy was fascinated by the phenomena of sleep and dreams. He composed a series of observations and judgements that were brought together under "my theory of sleep". Tolstoy was constantly preoccupied with the basic principles of "the theory". It is hard to name a work by him where a description of sleep and/or a dream does not play a vital role in the unfolding of the plot. They testify to Tolstoy's interest in the mechanism of sleep and in the processes of falling asleep and waking up. Tolstoy viewed sleep as a specific state of consciousness, and he subsequently linked the concept of sleep with the concept of death. For him sleep and awakening were experiences emblematic of life and death.

  2. Meie poliitikute seitse viga / Leo Kunnas

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2008-01-01

    Artikkel põhineb reservkolonelleitnant Leo Kunnase mõttepäeval "Isemõtlejad iseolemisest" peetud ettekandel, kus ta toob välja 1930-ndatele aastatele ja tänapäevale iseloomulikud poliitkute eksimused

  3. The Resolved Stellar Population of Leo A

    Science.gov (United States)

    Tolstoy, Eline

    1996-05-01

    New observations of the resolved stellar population of the extremely metal-poor Magellanic dwarf irregular galaxy Leo A in Thuan-Gunn r, g, i, and narrowband Hα filters are presented. Using the recent Cepheid variable star distance determination to Leo A by Hoessel et al., we are able to create an accurate color-magnitude diagram (CMD). We have used the Bavesian inference method described by Tolstoy & Saha to calculate the likelihood of a Monte Carlo simulation of the stellar population of Leo A being a good match to the data within the well understood errors in the data. The magnitude limits on our data are sensitive enough to look back at ~1 Gyr of star formation history at the distance of Leo A. To explain the observed ratio of red to blue stars in the observed CMD, it is necessary to invoke either a steadily decreasing star formation rate toward the present time or gaps in the star formation history. We also compare the properties of the observed stellar population with the known spatial distribution of the H I gas and H II regions to support the conclusions from CMD modeling. We consider the possibility that currently there is a period of diminished star formation in Leo A, as evidenced by the lack of very young stars in the CMD and the faint H II regions. How the chaotic H I distribution, with no observable rotation, fits into our picture of the evolution of Leo A is as yet unclear.

  4. Leo Metsari tõlkepärl / Aivar Kull

    Index Scriptorium Estoniae

    Kull, Aivar, 1955-

    2002-01-01

    Arvustus: Mann, Thomas. Lotte Weimaris / tlk. Leo Metsar. Tln. : Eesti Raamat, 2001. (Nobeli laureaat). Vaata ka: Kull, Aivar. Kulli pilk. - Tartu : Ilmamaa, 2005, lk. 68-69, pealkirjaga "Goethe, Thomas Mann ja Leo Metsar"

  5. XML Format for SESAME and LEOS

    Energy Technology Data Exchange (ETDEWEB)

    Durrenberger, J K; Neely, J R; Sterne, P A

    2009-04-29

    The objective of this document is to describe the XML format used by LLNL and LANL to represent the equation-of-state and related material information in the LEOS and SESAME data libraries. The primary purpose of this document is to describe a specific XML format for representing EOS data that is tailored to the nature of the underlying data and is amenable to conversion to both legacy SESAME and LEOS binary formats. The secondary purpose is to describe an XML format that lends itself to a 'natural' representation in a binary file format of the SESAME, pdb or hdf5 form so that this format and related tools can be used for the rapid and efficient development and implementation of prototype data structures. This document describes the XML format only. A working knowledge of LEOS and SESAME formats is assumed.

  6. NASA STD-4005: The LEO Spacecraft Charging Design Standard

    Science.gov (United States)

    Ferguson, Dale C.

    2006-01-01

    Power systems with voltages higher than about 55 volts may charge in Low Earth Orbit (LEO) enough to cause destructive arcing. The NASA STD-4005 LEO Spacecraft Charging Design Standard will help spacecraft designers prevent arcing and other deleterious effects on LEO spacecraft. The Appendices, an Information Handbook based on the popular LEO Spacecraft Charging Design Guidelines by Ferguson and Hillard, serve as a useful explanation and accompaniment to the Standard.

  7. [Leo Sternbach, an inventor of benzodiazepines].

    Science.gov (United States)

    Uchibayashi, Masao

    2007-01-01

    A biography of Leo Sternbach, an inventor of benzodiazepine tranquillizers, is presented. It consists of (1) a societal desire for lifestyle pills, (2) Leo's birth in 1908 and youth, (3) education, (4) in Vienna, (5) in Zurich, (6) at Hoffmann-La Roche, Basel, (7) to the New World, (8) at Roche, Nutley NJ, (9) invention of the new drugs, (10) revolution of people's lifestyle, and (11) reward, retirement and obituary in 2005. This paper may be the first comprehensive biography of this remarkable chemist written in Japanese.

  8. Analysis list: Leo1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Leo1 Muscle + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Leo1.1.tsv ...http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Leo1.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Leo...1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Leo1.Muscle.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Muscle.gml ...

  9. In Memory of Leo P. Kadanoff

    Science.gov (United States)

    Wegner, Franz J.

    2016-10-01

    Leo Kadanoff has worked in many fields of statistical mechanics. His contributions had an enormous impact. This holds in particular for critical phenomena, where he explained Widom's homogeneity laws by means of block-spin transformations and laid the basis for Wilson's renormalization group equation. I had the pleasure to work in his group for 1 year. A short historical account is given.

  10. In memory of Leo P. Kadanoff

    CERN Document Server

    Wegner, Franz J

    2016-01-01

    Leo Kadanoff has worked in many fields of statistical mechanics. His contributions had an enormous impact. This holds in particular for critical phenomena, where he explained Widom's homogeneity laws by means of block-spin transformations and laid the basis for Wilson's renormalization group equation. I had the pleasure to work in his group for one year. A short historically account is given.

  11. The Ancient stellar population of Leo A.

    NARCIS (Netherlands)

    Saha, Abhijit; Fiorentino, Giuliana; Tolstoy, Eline; Cole, Andrew

    2010-01-01

    The primary goal of our proposal is the characterisation of the oldest stellar populations in Leo A using the properties of ancient RR Lyrae variable stars as tracers. Well known and long established correlations exist between the periods and luminosities of RR Lyrae variable stars and their ages an

  12. Challenging Christianity: Leo Tolstoy and Religious Education

    Science.gov (United States)

    Moulin, Dan

    2009-01-01

    The religious thought of Russian novelist Leo Tolstoy is a well documented but often overlooked example of unorthodox Christianity. This paper uses the example of Tolstoy's religious thinking to question the integrity of the current representation of Christianity in UK schools. It also uses Tolstoy's criticism of orthodox Christianity to suggest a…

  13. A Collisional Origin for the Leo Ring

    NARCIS (Netherlands)

    Michel-Dansac, Leo; Duc, Pierre-Alain; Bournaud, Frederic; Cuillandre, Jean-Charles; Emsellem, Eric; Oosterloo, Tom; Morganti, Raffaella; Serra, Paolo; Ibata, Rodrigo

    2010-01-01

    Extended H I structures around galaxies are of prime importance for probing galaxy formation scenarios. The giant H I ring in the Leo group is one of the largest and most intriguing H I structures in the nearby universe. Whether it consists of primordial gas, as suggested by the apparent absence of

  14. What Happened to Leo P's Metals?

    Science.gov (United States)

    Kohler, Susanna

    2015-12-01

    Measurements of metal abundances in galaxies present a conundrum: compared to expectations, there are not nearly enough metals observed within galaxies. New observations of a nearby dwarf galaxy may help us understand where this enriched material went.Removal ProcessesStar formation is responsible for the build-up of metals (elements heavier than helium) in a galaxy. But when we use a galaxys star-formation history to estimate the amount of enriched material it should contain, our predictions are inconsistent with measured abundances: large galaxies contain only about 2025% of the expected metals, and small dwarf galaxies contain as little as 1%!So what happens to galaxies metals after they have been formed? The favored explanation is that metals are removed from galaxies via stellar feedback: stars that explode in violent supernovae can drive high-speed winds, expelling the enriched material from a galaxy. This process should be more efficient in low-mass galaxies due to their smaller gravitational wells, which would explain why low-mass galaxies have especially low metallicities.But external processes may also contribute to the removal of metals, such as tidal stripping during interactions between galaxies. To determine the role of stellar feedback alone, an ideal test would be to observe an isolated low-mass, star-forming galaxy i.e., one that is not affected by external processes.Luckily, such an isolated, low-mass galaxy has recently been discovered just outside of the Local Group: Leo P, a gas-rich dwarf galaxy with a total stellar mass of 5.6 x 105 solar masses.Isolated ResultsPercentage of oxygen lost in Leo P compared to the percentage of metals lost in three other, similar-size dwarfs that are not isolated. If the gas-phase oxygen in Leo P were removed, Leo Ps measurements would be consistent with those of the other dwarfs. [McQuinn et al. 2015]Led by Kristen McQuinn (University of Minnesota, University of Texas at Austin), a team of researchers has used

  15. LEO AUTONOMOUS NAVIGATION BASED ON IMAGE MOTION

    Institute of Scientific and Technical Information of China (English)

    DUANFang; LIUJian-ye; YUFeng

    2005-01-01

    A method of LEO autonomous navigation is presented based on the nonlinear satellite velocity relative to the earth. The velocity is detected by a high-speed camera, with the attitude information detected by a star sensor. Compared with traditional autonomous navigation by landmark identification, the satellite velocity relarive to the earth is obtained by correlativity analysis of images. It does not need to recognize ground objects or views. Since it is not necessary to pre-store the database of ground marks, lots of memory space can be saved.The state and observation equations are constructed, and the filtering is processed by the Kalman filter. Simulation results show that the system has high autonomous navigation precision in LEO autonomous navigation.

  16. Petróleo, Royalties e Pobreza

    OpenAIRE

    Gicélia Mendes da Silva; Vera Lúcia Alves França

    2009-01-01

    A exploração do petróleo se constitui num elemento significativo para a economia sergipana. A contradição existente entre o subsolo rico e a população pobre levanta indagações a respeito da gestão destes recursos e as condições de vida da população. Tais condições, aliadas à entrada de novos atores na exploração do petróleo em Sergipe e à gestão dos recursos advindos da exploração, vêm incutindo relações peculiares à política neoliberal na região e em Sergipe. O estudo foi desenvolvido a part...

  17. Nickel metal hydride LEO cycle testing

    Science.gov (United States)

    Lowery, Eric

    1995-01-01

    The George C. Marshall Space Flight Center is working to characterize aerospace AB5 Nickel Metal Hydride (NiMH) cells. The cells are being evaluated in terms of storage, low earth orbit (LEO) cycling, and response to parametric testing (high rate charge and discharge, charge retention, pulse current ability, etc.). Cells manufactured by Eagle Picher are the subjects of the evaluation. There is speculation that NiMH cells may become direct replacements for current Nickel Cadmium cells in the near future.

  18. Hugoniot Models for Na and LiF from LEOS

    Energy Technology Data Exchange (ETDEWEB)

    Whitley, Heather D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wu, Christine J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-12

    In this document, we provide the Hugoniot for sodium from two models: LEOS table L110 and Lynx table 110. We also provide the Hugoniot for lithium fluoride from LEOS (L2240) and Lynx (2240). The Hugoniot pressures are supplied for temperatures between 338.0 and 1.16×109 Kelvin and densities between 0.968 and 11.5 g/cc. These LEOS models were developed by the quotidian EOS methodology, which is a widely used and robust method for producing tabular EOS data. Tables list the model data for LEOS 110, Lynx 110, LEOS 2240, and Lynx 2240. The Lynx models follow the same methodology as the LEOS models; however, the Purgatorio average-atom DFT code was used to compute the electron thermal part of the EOS. The models for Lynx are only listed at high compression due to known issues with the Lynx library at lower pressures.

  19. Leo Satellite Communication through a LEO Constellation using TCP/IP Over ATM

    Science.gov (United States)

    Foore, Lawrence R.; Konangi, Vijay K.; Wallett, Thomas M.

    1999-01-01

    The simulated performance characteristics for communication between a terrestrial client and a Low Earth Orbit (LEO) satellite server are presented. The client and server nodes consist of a Transmission Control Protocol /Internet Protocol (TCP/IP) over ATM configuration. The ATM cells from the client or the server are transmitted to a gateway, packaged with some header information and transferred to a commercial LEO satellite constellation. These cells are then routed through the constellation to a gateway on the globe that allows the client/server communication to take place. Unspecified Bit Rate (UBR) is specified as the quality of service (QoS). Various data rates are considered.

  20. Leo Kunnas : triibuline särk kuuli ei peata / Leo Kunnas ; interv. Jaanus Piirsalu

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    2005. aastal koalitsioonijõudude koosseisus Iraagis teeninud Leo Kunnas selgitab intervjuus, mida on Eesti kaitsevägi Iraagi missioonist õppinud, millist mõju on Eesti sõdurite osalemine välismissioonides avaldanud ühiskonnale, lisaks võrdleb Iraagi ja Afganistani missioone ning põhjendab, miks on palgaarmee loomise idee Eestis sõjaliselt mitterelevantne

  1. Leo Kunnas : triibuline särk kuuli ei peata / Leo Kunnas ; interv. Jaanus Piirsalu

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    2005. aastal koalitsioonijõudude koosseisus Iraagis teeninud Leo Kunnas selgitab intervjuus, mida on Eesti kaitsevägi Iraagi missioonist õppinud, millist mõju on Eesti sõdurite osalemine välismissioonides avaldanud ühiskonnale, lisaks võrdleb Iraagi ja Afganistani missioone ning põhjendab, miks on palgaarmee loomise idee Eestis sõjaliselt mitterelevantne

  2. Introducing Leo LT - the "three-headed lion"

    Index Scriptorium Estoniae

    2008-01-01

    Leedu valitsus kiitis heaks seaduseparandused, mille tulemusena saab võtta tuumajaama ehitaja, investeerimis- ja energiafirma Leo LT strateegilise tähtsusega firmade hulka. Kui parlament valitsuse ettepanekud heaks kiidab, saab riik 61,7% Leo LT ja 38,3% NDX Energija aktsiatest

  3. Viiv enne kojuminekut / Leo Kunnas ; interv. Helen Arak

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude Peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas oma perekonnast, lapsepõlvekodust Põlvamaal ja praegusest elamisest Tallinnas, missioonil viibivate sõjaväelaste probleemidest ning eluolust Iraagis. Lisa: Katkend Leo Kunnase raamatust "Viiv pikas sõjas"

  4. POSSIBLE CHROMOSPHERIC ACTIVITY CYCLES IN AD LEO

    Energy Technology Data Exchange (ETDEWEB)

    Buccino, Andrea P.; Petrucci, Romina; Mauas, Pablo J. D. [Instituto de Astronomía y Física del Espacio (CONICET-UBA), C.C. 67 Sucursal 28, C1428EHA-Buenos Aires (Argentina); Jofré, Emiliano [Observatorio Astronómico de Córdoba, Córdoba (Argentina)

    2014-01-20

    AD Leo (GJ 388) is an active dM3 flare star that has been extensively observed both in the quiescent and flaring states. Since this active star is near the fully convective boundary, studying its long-term chromospheric activity in detail could be an appreciable contribution to dynamo theory. Here, using the Lomb-Scargle periodogram, we analyze the Ca II K line-core fluxes derived from CASLEO spectra obtained between 2001 and 2013 and the V magnitude from the ASAS database between 2004 and 2010. From both of these totally independent time series, we obtain a possible activity cycle with a period of approximately seven years and a less significant shorter cycle of approximately two years. A tentative interpretation is that a dynamo operating near the surface could be generating the longer cycle, while a second dynamo operating in the deep convection zone could be responsible for the shorter one. Based on the long duration of our observing program at CASLEO and the fact that we observe different spectral features simultaneously, we also analyze the relation between simultaneous measurements of the Na I index (R{sub D}{sup ′}), Hα, and Ca II K fluxes at different activity levels of AD Leo, including flares.

  5. Orbital List Ephemerides Design of LEO Navigation Augmentation Satellite

    Directory of Open Access Journals (Sweden)

    FANG Shanchuan

    2016-08-01

    Full Text Available A set of reliable LEO (low earth orbit broadcast ephemerides is required to be designed specifically if LEOs, with current GEOs, are also utilized as navigation augmentation satellites. The classical nine state parameters-based GLONASS-type broadcast ephemerides model can only represent precisely the 30-minute orbital motions of the medium and high earth orbiters. To directly deal with LEOs, a modified 21-parameter broadcast ephemerides model is proposed. First, the short-term variations of the main perturbation forces of LEOs are analyzed. Then a set of simple quadratic polynomials and harmonic functions is adopted to compensate mathematically atmospheric drag perturbation and other effects. A thoroughly simulation for the LEOs of altitude 500~1200 km is given to demonstrate the impact of the numbers of ephemerides parameters, the length of the fitting arcs and the sample rates on the fitting precision. The results of 20-minute fitting arc (approximately 1/5 of orbital period show that the average RMS of the fitting user range error (FURE is less than 0.05 m for LEOs higher than 700 km and within 0.03 m for LEOs of altitude 1000 km.

  6. Leo Kunnas, sõdurjumala teener / Leo Kunnas ; interv. Eve Jaakson

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas räägib Iraagi sõja kogemustest ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", riigikaitsest, kaitseväeteenistusest, kaitseminister Jürgen Ligist, kaitsepoliitikast, NATO-st, sõjalisest koostööst, perekonnast. Kommenteerivad Sten Reimann ja Venno Loosaar

  7. Leo Kunnas, sõdurjumala teener / Leo Kunnas ; interv. Eve Jaakson

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas räägib Iraagi sõja kogemustest ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", riigikaitsest, kaitseväeteenistusest, kaitseminister Jürgen Ligist, kaitsepoliitikast, NATO-st, sõjalisest koostööst, perekonnast. Kommenteerivad Sten Reimann ja Venno Loosaar

  8. ISIS Electronics Flying on Korean LEO Satellites

    Science.gov (United States)

    Remy, S.; Mosset, E.; Park, Sungwoo

    2014-08-01

    Saft (Defense & Space, France), ASP (Advanced Space Power, Germany) and KARI (Korean Aerospace Research Institute, South Korea) developed an autonomous battery management system to carry out cell packages balancing, by-pass system activation and cell package discharge after failure detection. This high reliability electronics called ISIS (Intelligent Surveillance Integrated System) has been designed, tested and qualified in the frame of the Kompsat-3, Kompsat-5 and Kompsat-3A large LEO Korean KARI Satellites. Kompsat-3 and 3A (4.8 kWh battery) and Kompsat-5 (5.2 kWh battery equipped with a demanding imaging radar system) are powered during daily sun eclipses with respectively one 4P12S or 4P13S VES100 li-ion batteries managed by ISIS system.

  9. Demonstration of Uncued Optical Surveillance of LEO

    Science.gov (United States)

    Zimmer, P.; Ackermann, M.; McGraw, J.

    2014-09-01

    J.T. McGraw and Associates, LLC, in collaboration with the University of New Mexico (UNM), has built and is operating two proof-of-concept wide-field imaging systems to test novel techniques for uncued surveillance of LEO. The imaging systems are built from off-the-shelf optics and detectors resulting in a 350mm aperture and a 6 square degree field of view. For streak detection, field of view is of critical importance because the maximum exposure time on the object is limited by its crossing time and measurements of apparent angular motion are better constrained with longer streaks. The current match of the detector to the optical system is optimized for detection of objects at altitudes above 450km, which for a circular orbit, corresponds to apparent motions of approximately 1 deg./sec. Using our GPU-accelerated detection scheme, the proof-of-concept systems have detected objects fainter than V=12.3, which approximately corresponds to a 24 cm object at 1000 km altitude at better than 6 sigma significance, from sites near and within Albuquerque, NM. This work demonstrates scalable optical systems designed for near real time detection of fast moving objects, which can be then handed off to other instruments capable of tracking and characterizing them. The two proof-of-concept systems, separated by ~30km, work together by taking simultaneous images of the same orbital volume to constrain the orbits of detected objects using parallax measurements. These detections are followed-up by photometric observations taken at UNM to independently assess the objects and the quality of the derived orbits. We believe this demonstrates the potential of small telescope arrays for detecting and cataloguing heretofore unknown LEO objects.

  10. Dynamic Characteristics of Inter-Satellite Links in LEO Networks

    Institute of Scientific and Technical Information of China (English)

    王亮; 张乃通; 温萍萍

    2003-01-01

    To establish an efficient inter-satellite link (ISL) in an LEO network, the effect of geometric characteristics of ISL on the ISLs and the devices on the LEO satellite should be examined. Because of the continuous movement of the LEO satellite, the time-varying behaviours of the ISL's geometric charactersistics continuously change with the changes of the satellite's position on the orbit. These dynamic geometric characteristics of the ISLs are important for ISL's performance analyzing and the design of the devices on the LEO satellite. This paper describes dynamic geometric characteristics of ISL, analyzes the impact of these regulations on the tracking system of the satellite's antenna and the power adjusting system of the satellite's transmitter, with the Iridium system as an example.

  11. Performances of Saft Lithium-Ion Cells in LEO Cycling

    Directory of Open Access Journals (Sweden)

    Prevot D.

    2017-01-01

    The article will thus present the whole LEO cycling results available for the two cells, and will provide afterwards the correlation status of Saft Li-ion Model (SLIM with all the experimental data acquired.

  12. Hugoniot Models for Na and LiF from LEOS

    Energy Technology Data Exchange (ETDEWEB)

    Whitley, Heather D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wu, Christine J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-12

    In this document, we provide the Hugoniot for sodium from two models: LEOS table L110 and Lynx table 110. We also provide the Hugoniot for lithium fluoride from LEOS (L2240) and Lynx (2240). The Hugoniot pressures are supplied for temperatures between 338.0 and 1.16×109 Kelvin and densities between 0.968 and 11.5 g/cc. These LEOS models were developed by the quotidian EOS methodology, which is a widely used and robust method for producing tabular EOS data.[1, 2] Table 1 lists the model data for LEOS 110, Table 2 contains Lynx 110, Table 3 contains LEOS 2240, and Table 4 contains Lynx 2240. The Lynx models follow the same methodology as the LEOS models, however the Purgatorio[3] average-atom DFT code was used to compute the electron ther- mal part of the EOS. The models for Lynx are only listed at high compression due to known issues with the Lynx library at lower pressures.

  13. LEO P: AN UNQUENCHED VERY LOW-MASS GALAXY

    Energy Technology Data Exchange (ETDEWEB)

    McQuinn, Kristen B. W.; Skillman, Evan D.; Berg, Danielle [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Dolphin, Andrew [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Salzer, John J.; Rhode, Katherine L. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Adams, Elizabeth A. K. [ASTRON, the Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA, Dwingeloo (Netherlands); Giovanelli, Riccardo; Haynes, Martha P. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Girardi, Léo, E-mail: kmcquinn@astro.umn.edu [Osservatorio Astronomico di Padova, INAF, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy)

    2015-10-20

    Leo P is a low-luminosity dwarf galaxy discovered through the blind H i Arecibo Legacy Fast ALFA survey. The H i and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with active star formation, an underlying older population, and an extremely low oxygen abundance. We have obtained optical imaging with the Hubble Space Telescope to two magnitudes below the red clump in order to study the evolution of Leo P. We refine the distance measurement to Leo P to be 1.62 ± 0.15 Mpc, based on the luminosity of the horizontal branch stars and 10 newly identified RR Lyrae candidates. This places the galaxy at the edge of the Local Group, ∼0.4 Mpc from Sextans B, the nearest galaxy in the NGC 3109 association of dwarf galaxies of which Leo P is clearly a member. The star responsible for ionizing the H ii region is most likely an O7V or O8V spectral type, with a stellar mass ≳25 M{sub ⊙}. The presence of this star provides observational evidence that massive stars at the upper end of the initial mass function are capable of being formed at star formation rates as low as ∼10{sup −5} M{sub ⊙} yr{sup −1}. The best-fitting star formation history (SFH) derived from the resolved stellar populations of Leo P using the latest PARSEC models shows a relatively constant star formation rate over the lifetime of the galaxy. The modeled luminosity characteristics of Leo P at early times are consistent with low-luminosity dSph Milky Way satellites, suggesting that Leo P is what a low-mass dSph would look like if it evolved in isolation and retained its gas. Despite the very low mass of Leo P, the imprint of reionization on its SFH is subtle at best, and consistent with being totally negligible. The isolation of Leo P, and the total quenching of star formation of Milky Way satellites of similar mass, implies that the local environment dominates the quenching of the Milky Way satellites.

  14. The Fornax-Leo-Sculptor stream revisited

    Science.gov (United States)

    Majewski, Steven R.

    1994-08-01

    Lynden-Bell first demonstrated that the satellites of the Milky Way appear situated along two great 'streams' in the sky: the 'Magellanic stream' and the 'Fornax-Leo-Sculptor (FLS) stream.' Further exploration of the three-dimensional distribution of Galactic satellites reveals that the recently discovered Sextans and Phoenix dwarf spheroidal galaxies also lie near the plane defined by the FLS galaxies, and therefore strengthens the evidence in favor of the FLS stream. Moreover, a specific group of globular clusters -- those exhibiting the reddest horizontal branches (HBs) among those identified as 'young halo' by Zinn -- appear to populate the FLS stream. As previously demonstrated by Zinn, the spatial distribution of old halo globulars appears to be flattened toward the Galactic plane, and therefore the old halo clusters are typically anti-correlated to the nearly orthogonal FLS stream. A scenario is postulated wherein the Galactic satellites of the FLS stream and the red HB, young halo globular clusters share a common origin in the accretion of a formerly larger, parent satellite galaxy or Searle & Zinn 'fragment.'

  15. Possible chromospheric activity cycles in AD Leo

    CERN Document Server

    Buccino, Andrea P; Jofré, Emiliano; Mauas, Pablo J D

    2013-01-01

    AD Leo (GJ 388) is an active dM3 flare star extensively observed both in the quiescent and flaring states. Since this active star is near the fully-convective boundary, to study in detail its long-term chromospheric activity could be an appreciable contribution for the dynamo theory. Here, we analyze with the Lomb-Scargle periodogram the Ca II K line-core fluxes derived from CASLEO spectra obtained between 2001 and 2013 and the V magnitude from the ASAS database between 2004 and 2010. From both totally independent time-series, we obtain a possible activity cycle of period $\\sim7$ years and a less-significant shorter one of $\\sim2$ years. A tentative interpretation is that a dynamo operating near the surface could be generating the longer cycle, while a second dynamo operating in the deep convection zone could be responsible for the shorter one. Based on the long duration of our observing program at CASLEO and the fact that we observe simultaneously different spectral features, we also analyze the relation bet...

  16. PECULIAR VELOCITIES OF GALAXIES IN THE LEO SPUR

    Energy Technology Data Exchange (ETDEWEB)

    Karachentsev, Igor D.; Makarova, Lidia N.; Makarov, Dmitry I. [Special Astrophysical Observatory, the Russian Academy of Sciences, Nizhnij Arkhyz, Karachai-Cherkessian Republic, 369167 (Russian Federation); Tully, R. Brent [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Rizzi, Luca, E-mail: ikar@sao.ru [W. M. Keck Observatory, 65-1120 Mamalahoa Hwy., Kamuela, HI 9 6743 (United States)

    2015-06-01

    The Hubble Space Telescope Advanced Camera for Surveys has been used to determine accurate distances for the spiral galaxy NGC 2683 and 12 other galaxies in a zone of the “local velocity anomaly” from luminosity measurements of the brightest red giant branch stars. These galaxies lie in the Leo Spur, the nearest filament beyond our Local Sheet. The new accurate distance measurements confirm that galaxies along the Leo Spur are more distant than expected from uniform cosmic expansion, and hence have large and peculiar velocities toward us. The motions are generally explained by a previously published model that posits that the Local Sheet is descending at 259 km s{sup −1} toward the south supergalactic pole due to expansion of the Local Void and is being attracted toward the Virgo Cluster at 185 km s{sup −1}. With the standard ΛCDM cosmology, an empty void expands at 16 km s{sup −1} Mpc{sup −1}, so a motion of 259 km s{sup −1} requires the Local Void to be impressively large and empty. Small residuals from the published model can be attributed to an upward push toward the north supergalactic pole by the expansion of the Gemini–Leo Void below the Leo Spur. The Leo Spur is sparsely populated, but among its constituents there are two associations that contain only dwarf galaxies.

  17. A Novel Spacecraft Charge Monitor for LEO

    Science.gov (United States)

    Goembel, Luke

    2004-01-01

    Five years ago we introduced a new method for measuring spacecraft chassis floating potential relative to the space plasma (absolute spacecraft potential) in low Earth orbit. The method, based on a straightforward interpretation of photoelectron spectra, shows promise for numerous applications, but has not yet been tried. In the interest of testing the method, and ultimately supplying another tool for measuring absolute spacecraft charge, we are producing a flight prototype Spacecraft Charge Monitor (SCM) with support from NASA's Small Business Innovation Research (SBIR) program. Although insight into the technique came from data collected in space over two decades ago, very little data are available. The data indicate that it may be possible to determine spacecraft floating potential to within 0.1 volt each with the SCM second under certain conditions. It is debatable that spacecraft floating potential has ever been measured with such accuracy. The compact, easily deployed SCM also offers the advantage of long-term stability in calibration. Accurate floating potential determinations from the SCM could be used to correct biases in space plasma measurements and evaluate charge mitigation and/or sensing devices. Although this paper focuses on the device's use in low Earth orbit (LEO), the device may also be able to measure spacecraft charge at higher altitudes, in the solar wind, and in orbits around other planets. The flight prototype SCM we are producing for delivery to NASA in the third quarter of 2004 will measure floating potential from 0 to -150 volts with 0.1 volt precision, weigh approximately 600-700 grams, consume approximately 2 watts, and will measure approximately 8 x 10 x 17 cm.

  18. Packet routing algorithm for polar orbit LEO satellite constellation network

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Broadband satellite networks are capable of providing global coverage and support various services. The networks constructed by Low Earth Orbit (LEO) satellite constellations have attracted great interests because of their short round-trip delays and wide bandwidths. A challenging problem is to develop a simple and efficient packet routing algorithm for the LEO satellite constellation network. This paper presents a SpiderWeb Topological Network (SWTN) and a distributed packet routing algorithm for the LEO satellite constellation network based on the SWTN. The algorithm gives the minimum propagation delay paths with low computational complexity and requires no routing tables, which is practical for on-board processing. The performance of the algorithm is demonstrated through simulations.

  19. Ground-based optical observation system for LEO objects

    Science.gov (United States)

    Yanagisawa, T.; Kurosaki, H.; Oda, H.; Tagawa, M.

    2015-08-01

    We propose a ground-based optical observation system for monitoring LEO objects, which uses numerous optical sensors to cover a vast region of the sky. Its potential in terms of detection and orbital determination were examined. About 30 cm LEO objects at 1000 km altitude are detectable using an 18 cm telescope, a CCD camera and the analysis software developed. Simulations and a test observation showed that two longitudinally separate observation sites with arrays of optical sensors can identify the same objects from numerous data sets and determine their orbits precisely. The proposed system may complement or replace the current radar observation system for monitoring LEO objects, like space-situation awareness, in the near future.

  20. Passivation Strategies on Board Airbus ds Leo Pcdus

    Directory of Open Access Journals (Sweden)

    Lapeña Emilio

    2017-01-01

    This paper deals with the different strategies followed in the Airbus DS LEO PCDUs regarding the implementation of the passivation function in several LEO missions with different architectures (DET and MPPT solar array power conditioning. In the selection of the solution implemented in the frame of every mission, a key driver is the degree of advance in the test performed over flight representative battery modules regarding their safe behavior when deeply depleted after a long period in orbit with the passivation applied over the spacecraft.

  1. El petróleo como repelente de Phlebotomus

    Directory of Open Access Journals (Sweden)

    Marshall Hertig

    1943-09-01

    Full Text Available Se ha probado el repelente del petróleo contra el Phlebotomus verrucarum. Se echó varias veces petróleo en las paredes exteriores y en el suelo alrededor de casas en la zona verrucógena del Rímac, donde son abundantes las titiras. Inmediatamente después de cada petrolización se redujeron a números insignificantes las titiras dentro de las casas, efecto que duró aproximadamente una semana.

  2. Diario de un privilegiado durante el fascismo: Leo Ferrero

    Directory of Open Access Journals (Sweden)

    María Belén Hernández González

    2013-07-01

    Full Text Available La obra de Leo Ferrero, Diario de un privilegiado durante el fascismo, es un testimonio de la experiencia de la familia Ferrero Lombroso entre 1926 y 1927, obligada a la reclusión y aislamiento en su propia casa, por parte del régimen de Benito Mussolini. El texto anticipa en una década los escritos de la resistencia partisana. En este artículo se propone un panorama de la cultura en Italia en los años previos a la guerra, según la perspectiva crítica de Leo Ferrero.

  3. Avaliku võimu ja kodanikualgatuse partnerlus : koostööd mõjutavad tegurid / Krista Hinno, Tanel Vallimäe

    Index Scriptorium Estoniae

    Hinno, Krista

    2007-01-01

    Artiklis esitatakse kokkuvõte Tallinna Ülikooli Eesti Humanitaarinstituudi Kodanikeühiskonna Uurimis- ja Arenduskeskuse uurimuse "Avaliku võimu ja kodanikualgatuse komplementaarsed suhted" peamistest tulemustest. Raporti autorite hulka kuulusid Erle Rikmann, Krista Hinno, Aigi Bremse, Kersti Kollom, Mari Sepp ja Tanel Vallimäe. Toetudes uuringutele väidavad autorid, et Eesti ametnikkond on soodsalt meelestatud koostööle kodanikuühendustega, takistuseks võivad saada kodanikeühenduste erinev tööstiil, vajalike ressursside puudus, sh ka ajanappus, ametnike kaadrivoolavus ja teatavate vanusegruppide vähene avatus. Diagrammid: Koostöö jaotumine asutuseliikide vahel; Ametnike hinnang ühistegevuse sisukusele seoses koostöö algatamisega; Ametnike hinnang omaduse vajalikkusele oma töös (vastajate osakaal, kes peavad antud omadust oma töös väga vajalikuks)

  4. Avaliku võimu ja kodanikualgatuse partnerlus : koostööd mõjutavad tegurid / Krista Hinno, Tanel Vallimäe

    Index Scriptorium Estoniae

    Hinno, Krista

    2007-01-01

    Artiklis esitatakse kokkuvõte Tallinna Ülikooli Eesti Humanitaarinstituudi Kodanikeühiskonna Uurimis- ja Arenduskeskuse uurimuse "Avaliku võimu ja kodanikualgatuse komplementaarsed suhted" peamistest tulemustest. Raporti autorite hulka kuulusid Erle Rikmann, Krista Hinno, Aigi Bremse, Kersti Kollom, Mari Sepp ja Tanel Vallimäe. Toetudes uuringutele väidavad autorid, et Eesti ametnikkond on soodsalt meelestatud koostööle kodanikuühendustega, takistuseks võivad saada kodanikeühenduste erinev tööstiil, vajalike ressursside puudus, sh ka ajanappus, ametnike kaadrivoolavus ja teatavate vanusegruppide vähene avatus. Diagrammid: Koostöö jaotumine asutuseliikide vahel; Ametnike hinnang ühistegevuse sisukusele seoses koostöö algatamisega; Ametnike hinnang omaduse vajalikkusele oma töös (vastajate osakaal, kes peavad antud omadust oma töös väga vajalikuks)

  5. A New Approach for Enhanced Communication to LEO Satellites

    NARCIS (Netherlands)

    Gill, E.K.A.; Verhoeven, C.; Gill, K.; De Milliano, M.

    2010-01-01

    Operations of satellites in Low-Earth Orbit (LEO) have been based on exploiting the maximum time of visibility of satellites over their ground stations. In this paper, it is shown that a key parameter for communication between a satellite and a ground station is not the time of visibility but the am

  6. PACKET ROUTING ALGORITHM FOR LEO SATELLITE CONSTELLATION NETWORK

    Institute of Scientific and Technical Information of China (English)

    Wang Kaidong; Tian Bin; Yi Kechu

    2005-01-01

    A novel distributed packet routing algorithm for Low Earth Orbit (LEO) satellite networks based on spiderweb topology is presented. The algorithm gives the shortest path with very low computational complexity and without on-board routing tables, which is suitable and practical for on-board processing. Simulation results show its practicability and feasibility.

  7. Dynamic movement-based location update in LEO networks

    Institute of Scientific and Technical Information of China (English)

    王亮; 张乃通; 马永奎

    2003-01-01

    Mobility management is an important aspect of the LEO systems. In terrestrial wireless network, the movement of the user triggers the location updating and determines the paging scheme, while in LEO satellite systems, the location updating and paging is mainly based on the movement of satellite. Terrestrial location management techniques must be altered to fit LEO systems. This paper introduces a modified movement-based location update and paging scheme in LEO networks. In this scheme we propose the meta-cell concept, which includes two spot-beams of one satellite. First we present the location management scheme based on the architecture with meta-cell location area. Then an analytical model is applied to formulate the cost of location updating and location paging for the and movement meta-cell based dynamic location update scheme. The comparison of performance between meta-cell architecture method and conventional signal-spot-cell architecture method is provided to demonstrate the cost-effectiveness and robust of the proposed scheme under various parameters. To reduce the impact of meta-cell architecture on location paging cost, we present forced location update strategy which used in the cases that the meta-cell includes the two spot-beams from different satellites.

  8. [Leo Bormans. Õnn on] / Krista Kivisalu

    Index Scriptorium Estoniae

    Kivisalu, Krista, 1968-

    2015-01-01

    Tutvustus: Õnn on : kogu maailma õnneraamat : teadmisi ja tarkusi enam kui sajalt õnneasjatundjalt kogu maailmast / toimetanud Leo Bormans ; [inglise keelest tõlkinud Triin Aimla-Laid ; toimetanud Violetta Riidas ; originaali kujundus: Kris Demey] Ilmunud [Tallinn] : Pegasus, c2015

  9. In memoriam Prof. Dr. Leo Daniel Brongersma (1907-1994)

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1995-01-01

    A biography of Leo Daniel Brongersma is given, highlighting his significance for herpetology worldwide, and especially for snake anatomy, sea turtle distribution, faunistics of New Guinea and IndoAustralia. Lists of patronyms, of species named by Brongersma and of his publications are given. Also

  10. Complete mitochondrial genome of a Asian lion (Panthera leo goojratensis).

    Science.gov (United States)

    Li, Yu-Fei; Wang, Qiang; Zhao, Jian-ning

    2016-01-01

    The entire mitochondrial genome of this Asian lion (Panthera leo goojratensis) was 17,183 bp in length, gene composition and arrangement conformed to other lions, which contained the typical structure of 22 tRNAs, 2 rRNAs, 13 protein-coding genes and a non-coding region. The characteristic of the mitochondrial genome was analyzed in detail.

  11. Severe intestinal coccidiosis in a newborn lion (Panthera leo)

    Science.gov (United States)

    Severe coccidiosis was found in sections of small intestine of a less than 2 day old lion (Panthera leo) born in captivity. Schizonts, merozoites, gamonts, and unsporulated oocysts were located in epithelial cells of ileum. Ultrastructural examination indicated that schizonts divided by schizogony. ...

  12. In memoriam Prof. Dr. Leo Daniel Brongersma (1907-1994)

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1995-01-01

    A biography of Leo Daniel Brongersma is given, highlighting his significance for herpetology worldwide, and especially for snake anatomy, sea turtle distribution, faunistics of New Guinea and IndoAustralia. Lists of patronyms, of species named by Brongersma and of his publications are given. Also hi

  13. Leo P: An Unquenched Very Low-Mass Galaxy

    CERN Document Server

    McQuinn, Kristen B W; Dolphin, Andrew; Cannon, John M; Salzer, John J; Rhode, Katherine L; Adams, Elizabeth A K; Berg, Danielle; Giovanelli, Riccardo; Girardi, Léo; Haynes, Martha P

    2015-01-01

    Leo P is a low-luminosity dwarf galaxy discovered through the blind HI Arecibo Legacy Fast ALFA (ALFALFA) survey. The HI and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with active star formation, an underlying older population, and an extremely low oxygen abundance. We have obtained optical imaging from the Hubble Space Telescope to study the evolution of Leo P. We refine the distance measurement to Leo~P to be 1.62+/-0.15 Mpc, based on the luminosity of the horizontal branch stars and 10 newly identified RR Lyrae candidates. This places the galaxy at the edge of the Local Group, ~0.4 Mpc from the loose association of dwarfs that includes Sextans A, Sextans B, Antlia, and NGC 3109. The star responsible for ionizing the HII region is most likely an O7V or O8V spectral type, with a stellar mass >25 Msun. The presence of this star provides observational evidence that massive stars at the upper-end of the initial mass function are capable of being formed at star formation rate...

  14. Exploiting link dynamics in LEO-to-ground communications

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, Joseph Mcrae [Los Alamos National Laboratory; Caffrey, Michael P [Los Alamos National Laboratory

    2009-01-01

    The high dynamics of the LEO-to-ground radio channel are described. An analysis shows how current satellite radio systems largely underutilize the available radio link, and that a radio that can adaptively vary the bit rate can more fully exploit it, resulting in increased data throughput and improved power efficiency. We propose one method for implementing the adaptivity, and present simulation results.

  15. Moore'i seadus ja meie tulevik / Leo Võhandu

    Index Scriptorium Estoniae

    Võhandu, Leo, 1929-

    2006-01-01

    Kiibifirma Intel üks asutajaid Gordon Moore väitis 1965. aastal, et transistorite arv kiibil topeldub iga kahe aastaga ehk loomulik areng ei ole lineaarne, vaid eksponentsiaalne (astmeline). TTÜ emeriitprofessor Moore'i seaduse mõjust ühiskonna arengule. Vt. samas: Leo Võhandu

  16. In memoriam Prof. Dr. Leo Daniel Brongersma (1907-1994)

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1995-01-01

    A biography of Leo Daniel Brongersma is given, highlighting his significance for herpetology worldwide, and especially for snake anatomy, sea turtle distribution, faunistics of New Guinea and IndoAustralia. Lists of patronyms, of species named by Brongersma and of his publications are given. Also hi

  17. LeoA, B and C from enterotoxigenic Escherichia coli (ETEC are bacterial dynamins.

    Directory of Open Access Journals (Sweden)

    Katharine A Michie

    Full Text Available Escherichia coli (ETEC strain H10407 contains a GTPase virulence factor, LeoA, which is encoded on a pathogenicity island and has been shown to enhance toxin release, potentially through vesicle secretion. By sequence comparisons and X-ray structure determination we now identify LeoA as a bacterial dynamin-like protein (DLP. Proteins of the dynamin family remodel membranes and were once thought to be restricted to eukaryotes. In ETEC H10407 LeoA localises to the periplasm where it forms a punctate localisation pattern. Bioinformatic analyses of leoA and the two upstream genes leoB and leoC suggest that LeoA works in concert with a second dynamin-like protein, made up of LeoB and LeoC. Disruption of the leoAB genes leads to a reduction in secretion of periplasmic Tat-GFP and outer membrane OmpA. Our data suggest a role for LeoABC dynamin-like proteins in potentiating virulence through membrane vesicle associated toxin secretion.

  18. Hierarchical Supervisor and Agent Routing Algorithm in LEO/MEO Double-layered Optical Satellite Network

    Science.gov (United States)

    Li, Yongjun; Zhao, Shanghong

    2016-09-01

    A novel routing algorithm (Hierarchical Supervisor and Agent Routing Algorithm, HSARA) for LEO/MEO (low earth orbit/medium earth orbit) double-layered optical satellite network is brought forward. The so-called supervisor (MEO satellite) is designed for failure recovery and network management. LEO satellites are grouped according to the virtual managed field of MEO which is different from coverage area of MEO satellite in RF satellite network. In each LEO group, one LEO satellite which has maximal persistent link with its supervisor is called the agent. A LEO group is updated when this optical inter-orbit links between agent LEO satellite and the corresponding MEO satellite supervisor cuts off. In this way, computations of topology changes and LEO group updating can be decreased. Expense of routing is integration of delay and wavelength utilization. HSARA algorithm simulations are implemented and the results are as follows: average network delay of HSARA can reduce 21 ms and 31.2 ms compared with traditional multilayered satellite routing and single-layer LEO satellite respectively; LEO/MEO double-layered optical satellite network can cover polar region which cannot be covered by single-layered LEO satellite and throughput is 1% more than that of single-layered LEO satellite averagely. Therefore, exact global coverage can be achieved with this double-layered optical satellite network.

  19. LeoA, B and C from Enterotoxigenic Escherichia coli (ETEC) Are Bacterial Dynamins

    DEFF Research Database (Denmark)

    Michie, Katharine A; Boysen, Anders; Low, Harry H

    2014-01-01

    C suggest that LeoA works in concert with a second dynamin-like protein, made up of LeoB and LeoC. Disruption of the leoAB genes leads to a reduction in secretion of periplasmic Tat-GFP and outer membrane OmpA. Our data suggest a role for LeoABC dynamin-like proteins in potentiating virulence through...... membrane vesicle associated toxin secretion.......Escherichia coli (ETEC) strain H10407 contains a GTPase virulence factor, LeoA, which is encoded on a pathogenicity island and has been shown to enhance toxin release, potentially through vesicle secretion. By sequence comparisons and X-ray structure determination we now identify Leo...

  20. Telelegend Leo Karpin : ETV uus juhtkond teeb vaid lammutustööd / Leo Karpin ; interv. Verni Leivak

    Index Scriptorium Estoniae

    Karpin, Leo, 1946-2014

    2004-01-01

    Pea 40 aastat Eesti Televisioonis töötanud telerežissöör oma teletöölt lahkumise põhjustest. Lisaks kommentaar "ETV juhatuse esimees Ilmar Raag, miks tunnustatud telemees Leo Karpin ametist vabastati?"

  1. Telelegend Leo Karpin : ETV uus juhtkond teeb vaid lammutustööd / Leo Karpin ; interv. Verni Leivak

    Index Scriptorium Estoniae

    Karpin, Leo, 1946-2014

    2004-01-01

    Pea 40 aastat Eesti Televisioonis töötanud telerežissöör oma teletöölt lahkumise põhjustest. Lisaks kommentaar "ETV juhatuse esimees Ilmar Raag, miks tunnustatud telemees Leo Karpin ametist vabastati?"

  2. Distributed Traffic Balancing Routing for LEO Satellite Networks

    Directory of Open Access Journals (Sweden)

    Yong Lu

    2013-11-01

    Full Text Available Satellite networks have been widely investigated both in the business and academia for many years, with many important routing algorithms reported in the literatures. However, fewer existing routing algorithms focus on the trade-off between the routing survivability and the routing computation and storage overheads. Due to topological dynamics, it is difficult to effectively apply the conventional routing protocols such as RIP or OSPF to Low Earth Orbit (LEO satellite networks. According to the virtual topology model based on virtual node, this paper propose a new fully distributed routing protocol for LEO satellite networks, called Distributed Traffic Balancing Routing (DTBR. The proposed protocol not only guarantees the routing survivability and provides the ability of traffic balancing, but also result in few additional computation and storage overheads only deriving from the information flooding of failed satellites. Simulation results demonstrate positive conclusions of our methods.

  3. Introducing the Leadership in Enabling Occupation (LEO) model.

    Science.gov (United States)

    Townsend, Elizabeth A; Polatajko, Helene J; Craik, Janet M; von Zweck, Claudia M

    2011-10-01

    Occupational therapy is a broad profession yet access to services remains restricted and uneven across Canada. Access to the potential breadth of occupational therapy is severely restrained by complex supply, retention, and funding challenges. To improve access to occupational therapy, widespread leadership is needed by all practitioners. This brief report introduces the Leadership in Enabling Occupation (LEO) Model, which displays the inter-relationship of four elements of everyday leadership as described in "Positioning Occupational Therapy for Leadership," Section IV, of Enabling Occupation II: Advancing a Vision of Health, Well-being and Justice through Occupation (Townsend & Polatajko, 2007). All occupational therapists have the power to develop leadership capacity within and beyond designated leadership positions. LEO is a leadership tool to extend all occupational therapists' strategic use of scholarship, new accountability approaches, existing and new funding, and workforce planning to improve access to occupational therapy.

  4. Exocomet signatures around the A-shell star $\\Phi$ Leo?

    CERN Document Server

    Eiroa, C; Montesinos, B; Villaver, E; Absil, O; Henning, Th; Bayo, A; Canovas, H; Carmona, A; Chen, Ch; Ertel, S; Iglesias, D P; Launhardt, R; Maldonado, J; Meeus, G; Moór, A; Mora, A; Mustill, A J; Olofsson, J; Rauw, G; Riviere-Marichalar, P; Roberge, A

    2016-01-01

    We present an intensive monitoring of high-resolution spectra of the Ca {\\sc ii} K line in the A7IV shell star $\\Phi$ Leo at very short (minutes, hours), short (night to night), and medium term (weeks, months) timescales. The spectra show remarkable variable absorptions on timescales of hours, days and months. The characteristics of these sporadic events are very similar to most of the ones observed towards the debris disk host star $\\beta$ Pic, which are usually interpreted as signs of the evaporation of solid, comet-like bodies grazing or falling onto the star. Therefore, our results suggest the presence of solid bodies around $\\Phi$ Leo. To our knowledge, with the exception of $\\beta$ Pic, our monitoring is the one with the best time resolution at the mentioned timescales done on a star with events attributed to exocomets. Assuming the cometary scenario, and considering the timescales of our monitoring, our results point to $\\Phi$ Leo presenting the richest environment with comet-like events yet known, sec...

  5. Leo-Based Optical/Microwave Terrestrial Communications

    CERN Document Server

    Meulenberg, Andrew; Ramanathan, Shivram

    2010-01-01

    We propose a LEO-based communication system that is built by deploying circum-terra, optic fibers connecting hundreds of small (perhaps) phased-array-communications and RF-signal-transfer antennas around the earth on multiple rings. The proposed LEO-earth connection will be through microwave links (Ku or low-Ka band) and many of the ISL's through the optic-fiber rings. Inter-ring connectivity could be with either high-Ka band or optical (laser) links. The initial ring would serve to complement existing terrestrial fiber networks; but, the system would expand with additional rings into non-equatorial planes to provide global connectivity. The proposed system would make use of connectivity & broadcasting capability of satellite constellations as well as the high throughput point-to-point capability of optic-fiber systems. The advantages, options, and economics of the proposed LEO optic-fiber / microwave communication system over existing terrestrial- and space-communication systems (of similar functionality...

  6. Técnica do aproveitamento da papila íleo-cecal naileostomia definitiva e na anastomose íleo-retal

    OpenAIRE

    Silva,Alcino Lázaro da

    2011-01-01

    INTRODUÇÃO: Quando se faz ileostomia com a papila, a perda líquida é bem menor e a irritação local às vezes é nula, podendo o paciente viver sem o uso da bolsa. OBJETIVO: Mostrar uma técnica operatória em que se preserva a papila na ileostomia ou na anastomose íleo-retal. Ela consta da preservação da vasculatura do ceco e íleo terminal e secção do ceco deixando-se 1 cm de orla na papila ileal que é fixada na pele por contra-abertura para ileostomia definitiva. Quando se resseca o cólon, a pap...

  7. NASA-STD-4005 and NASA-HDBK-4006, LEO Spacecraft Solar Array Charging Design Standard

    Science.gov (United States)

    Ferguson, Dale C.

    2007-01-01

    Two new NASA Standards are now official. They are the NASA LEO Spacecraft Charging Design Standard (NASA-STD-4005) and the NASA LEO Spacecraft Charging Design Handbook (NASA-HDBK-4006). They give the background and techniques for controlling solar array-induced charging and arcing in LEO. In this paper, a brief overview of the new standards is given, along with where they can be obtained and who should be using them.

  8. Hinnangud võtmeesinejatele / Leo Voogt ; inglise keelest tõlkinud Kristina Pai

    Index Scriptorium Estoniae

    Voogt, Leo

    2012-01-01

    Euroopa teadusraamatukogude organisatsiooni LIBER-i tegevdirektori Leo Voogti seisukohad Tartus 27.-30. juunil 2012 peetud konverentsi ettekandjate kohta, lisaks konverentsi ankeetides tagasisidena kajastunu

  9. Hinnangud võtmeesinejatele / Leo Voogt ; inglise keelest tõlkinud Kristina Pai

    Index Scriptorium Estoniae

    Voogt, Leo

    2012-01-01

    Euroopa teadusraamatukogude organisatsiooni LIBER-i tegevdirektori Leo Voogti seisukohad Tartus 27.-30. juunil 2012 peetud konverentsi ettekandjate kohta, lisaks konverentsi ankeetides tagasisidena kajastunu

  10. The Development of LEO/MEO Satellite Communication Systems%LEO/MEO卫星通信系统发展展望

    Institute of Scientific and Technical Information of China (English)

    李斗; 项海格

    2003-01-01

    本文简述了LEO/MEO卫星通信系统的主要特点,并介绍了几个典型的LEO/MEO卫星通信系统,如Iridium、Globalstar、ICO、Teledesic、Skybridge系统.还从星座、频率、星上处理及星际链路、无线技术、网络技术等方面讨论了LEO/MEO卫星通信系统的发展趋势和研究热点.

  11. Impact of GPS tracking data of LEO satellites on global GPS solutions

    Science.gov (United States)

    Rothacher, M.; Svehla, D.

    Already at present quite a few Low Earth Orbiting (LEO) satellites (SAC-C, CHAMP, JASON-1, GRACE-1 and GRACE-2) are equipped with one or more GPS receivers for precise orbit determination or other applications (atmospheric sounding, gravity field recovery, . . . ). This trend will continue in the near future (e.g., with the GOCE and COSMIC missions) and we will soon have an entire "constellation" of LEO satellites tracked by GPS at our disposal. In this contribution we want to study the impact of LEO GPS measurements (from a single LEO satellite or from a LEO constellation) on global GPS solutions, where GPS satellite orbits and clocks, Earth rotation parameters (ERPs), station coordinates and troposphere zenith delays are determined simultaneously using the data of the global network of the International GPS Service (IGS). In order to assess the impact of the LEO GPS data on global IGS results, we have to perform a combined analysis of the space-borne and the ground-based GPS data. Such a combination may benefit on one hand from the differences between a ground station and a LEO, e.g., (1) the different tracking geometry (coverage of isolated geographical areas by LEOs, rapidly changing geometry, . . . ), (2) that LEOs connect all ground stations within 1-2 hours, (3) that baselines between LEO and ground stations may be longer than station-station baselines, (4) that no tropospheric delays have to be estimated for LEOs, and (5) that LEOs orbit the Earth within the ionosphere and may therefore contribute to global ionosphere models. On the other hand we have to deal with difficult aspects of precise orbit determination for the LEOs: only if we succeed to obtain very accurate dynamic or reduced-dynamic orbits for the LEOs, we will have a chance at all to improve the global GPS results. We present first results concerning the influence of LEO data on GPS orbits, ERPs, site coordinates, and troposphere zenith delays using both, variance-covariance analyses based on

  12. Hibridismos musicais: Leo Brouwer e a Sonata del Caminante

    OpenAIRE

    Franco, Luan José [UNESP

    2013-01-01

    O presente trabalho disserta sobre hibridismos em música, sobretudo na obra violonística do cubano Leo Brouwer. Foi feita uma discussão de caráter geral sobre os diversos usos de hibridismos presentes em algumas músicas de compositores latinoamericanos. Para tanto foram abordados alguns autores dos chamados estudos culturais, por tratarem especificamente desse tema, ainda que usem outros termos ou palavras. Com isso pretende-se dar aos intérpretes de violão subsídios baseados na diversidade c...

  13. Sistema Aquíleo Calcáneo Plantar

    OpenAIRE

    Leal Serra, V.

    2010-01-01

    El Sistema Aquíleo Calcáneo Plantar fue descrito por los Profesores Arandes y Viladot el año 1953 demostrando cómo el Tríceps sural que termina en el tendón de Aquiles, se refleja en la tuberosidad del calcáneo, continuando con la aponeurosis plantar y la musculatura corta plantar, hasta llegar a insertarse en los dedos del pie. Esto representó, desde el punto de vista biomecánico, un gran avance para la comprensión de la marcha, la carrera y el salto en el homo erectus. The Achillean-calc...

  14. Reading Claude Lefort: Following the Footprints of Leo Strauss

    Directory of Open Access Journals (Sweden)

    Claudia Hilb

    2015-12-01

    Full Text Available It might seem outlandish to examine the theoretical links between the work of Claude Lefort, a left-wing French student of democracy, and Leo Strauss, the radical critic of modern mass democracy, usually associated with conservativism in North American political thought. Nonetheless, every reader of Lefort is certainly aware of his respect for Strauss’s reading of Machiavelli and for the Straussian insights into modern political thought. This article tries to make sense of Lefort’s dialogue with Strauss, both in its explicit and implicit aspects, focusing on the fundamental points of agreement and on the most relevant differences between the two authors.

  15. Akadeemik Leo Jürgenson 100 / Avo Suurvärav

    Index Scriptorium Estoniae

    Suurvärav, Avo

    2001-01-01

    Eesti Teaduste Akadeemia, Tallinna Tehnikaülikool ja Tallinna Teadlaste Maja tähistasid tehnikateadlase, õppejõu, ehitusspetsialisti akadeemik Leo Jürgensoni 100. sünniaastapäeva. Tallinna Tehnikaülikoolis on avatud näitus "Akadeemik Leo Jürgenson 100"

  16. Kartellidevastane leebusprogramm / Tanel Kalmet

    Index Scriptorium Estoniae

    Kalmet, Tanel, 1973-

    2010-01-01

    Veebruaris 2010 jõustunud karistusseadustiku, konkurentsiseaduse ja kriminaalmenetluse seadustiku muudatusest (RT I 2010,8,34), millega võeti Eestis kasutusele nn kartellidevastane leebusprogramm. Konkurentsikäitumisest ja leebusprogrammi toimimisviisist mänguteooria alusel

  17. Disainitud jumalad / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Rotermanni kvartali elevaatoris 25. septembrini avatud Disainiöö näitusest "Man & God" ("Inimene ja jumal"). Art4Souli projekt tegeleb inimese ja jumala suhtega. Kokkuleppeliselt on valitud sõnumit kandvaks disainiobjektiks matrjoška. Domineerivad Aasia kunstnikud

  18. Turunduskunsti tippteos / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2008-01-01

    Kokkupandavast nüüdiskunsti galeriist Mobile Art, mis alates 2008.a. veebruarist on rännanud Hongkongist Tokyosse ja oktoobris jõuab New Yorki. Idee autor Coco Chaneli moemaja juht ja disainer Karl Lagerfeld, arhitekt Zaha Hadid. Näitusel eksponeeritud tööde teemaks on Chaneli käekott

  19. Turunduskunsti tippteos / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2008-01-01

    Kokkupandavast nüüdiskunsti galeriist Mobile Art, mis alates 2008.a. veebruarist on rännanud Hongkongist Tokyosse ja oktoobris jõuab New Yorki. Idee autor Coco Chaneli moemaja juht ja disainer Karl Lagerfeld, arhitekt Zaha Hadid. Näitusel eksponeeritud tööde teemaks on Chaneli käekott

  20. Kunstielamus hotellist? / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Berliini Marienbadi hotellis on kunstnikel võimalus tasuda ööbimise eest ka kunstiga. Originaalkunstist Eesti hotellides. Pädaste mõisast kui ühest kunstisõbralikumast hotellist Eestis. Lühtrite ja käepidemete autor on šveitsi kunstnik Heinz Julen. Hoones on eksponeeritud itaalia skulptori Alfio Castelli personaalkogu, eesti klassikute töid. Tallinna Susi hotelli kunstikogust. Hotelli omanik sisearhitekt Jüri Uppin

  1. Kimono kodustamine / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Eesti Moekunstnike Ühenduse näitus "Kodustatud kimonod" Eesti Vabaõhumuuseumi Pulga talus 31. aug.-ni 2011. Näeb Taisho (1912-1926) ja Showa (1926-1989) ajastu kimonotest inspireeritud 15 eesti moekunstniku tänapäevaseid visioone ja jaapani moekunstnik-kuraatori Yumiko Okazaki loomingut

  2. Kunstielamus hotellist? / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Berliini Marienbadi hotellis on kunstnikel võimalus tasuda ööbimise eest ka kunstiga. Originaalkunstist Eesti hotellides. Pädaste mõisast kui ühest kunstisõbralikumast hotellist Eestis. Lühtrite ja käepidemete autor on šveitsi kunstnik Heinz Julen. Hoones on eksponeeritud itaalia skulptori Alfio Castelli personaalkogu, eesti klassikute töid. Tallinna Susi hotelli kunstikogust. Hotelli omanik sisearhitekt Jüri Uppin

  3. Raamat / Tanel Verk

    Index Scriptorium Estoniae

    Verk, Tanel

    2007-01-01

    Dirigent Neeme Järvi elulooalbumi "Neeme Järvi. Kunstniku elu / The Maestro's Touch" esitlusest Tallinnas Viru Keskuse raamatupoes Rahva Raamat, pidulikust albumi esitlusest 15. aug. Eesti Teatri- ja Muusikamuuseumis

  4. Kartellidevastane leebusprogramm / Tanel Kalmet

    Index Scriptorium Estoniae

    Kalmet, Tanel, 1973-

    2010-01-01

    Veebruaris 2010 jõustunud karistusseadustiku, konkurentsiseaduse ja kriminaalmenetluse seadustiku muudatusest (RT I 2010,8,34), millega võeti Eestis kasutusele nn kartellidevastane leebusprogramm. Konkurentsikäitumisest ja leebusprogrammi toimimisviisist mänguteooria alusel

  5. Raamat / Tanel Verk

    Index Scriptorium Estoniae

    Verk, Tanel

    2007-01-01

    Dirigent Neeme Järvi elulooalbumi "Neeme Järvi. Kunstniku elu / The Maestro's Touch" esitlusest Tallinnas Viru Keskuse raamatupoes Rahva Raamat, pidulikust albumi esitlusest 15. aug. Eesti Teatri- ja Muusikamuuseumis

  6. KKK - komando / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Eesti modellidest Karmen Pedarust, kes on 32. kohal ja Kätlin Aasast, kes on 48. kohal maailma nõutuimate modellide edetabelis ning Kelli Lumist, nende karjääri lühiandmed. Hamburgis sündinud supermodellist Tatjana Patitzist, kelle ema oli Eestist. Modellitööst ja välismaal edukalt modellikarjääri teinud eesti tüdrukutest räägivad Paolo Moglia, Margit Jõgger ja Katrin Rannaväli. Modell Beatrice moekoolist Agency Beata

  7. KKK - komando / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Eesti modellidest Karmen Pedarust, kes on 32. kohal ja Kätlin Aasast, kes on 48. kohal maailma nõutuimate modellide edetabelis ning Kelli Lumist, nende karjääri lühiandmed. Hamburgis sündinud supermodellist Tatjana Patitzist, kelle ema oli Eestist. Modellitööst ja välismaal edukalt modellikarjääri teinud eesti tüdrukutest räägivad Paolo Moglia, Margit Jõgger ja Katrin Rannaväli. Modell Beatrice moekoolist Agency Beata

  8. The PAF1 complex component Leo1 is essential for cardiac and neural crest development in zebrafish.

    Science.gov (United States)

    Nguyen, Catherine T; Langenbacher, Adam; Hsieh, Michael; Chen, Jau-Nian

    2010-05-01

    Leo1 is a component of the Polymerase-Associated Factor 1 (PAF1) complex, an evolutionarily conserved protein complex involved in gene transcription regulation and chromatin remodeling. The role of leo1 in vertebrate embryogenesis has not previously been examined. Here, we report that zebrafish leo1 encodes a nuclear protein that has a similar molecular structure to Leo1 proteins from other species. From a genetic screen, we identified a zebrafish mutant defective in the leo1 gene. The truncated Leo1(LA1186) protein lacks a nuclear localization signal and is distributed mostly in the cytoplasm. Phenotypic analysis showed that while the initial patterning of the primitive heart tube is not affected in leo1(LA1186) mutant embryos, the differentiation of cardiomyocytes at the atrioventricular boundary is aberrant, suggesting a requirement for Leo1 in cardiac differentiation. In addition, the expression levels of markers for neural crest-derived cells such as crestin, gch2, dct and mitfa are greatly reduced in leo1(LA1186) mutants, indicating a requirement for Leo1 in maintaining the neural crest population. Consistent with this finding, melanocyte and xanthophore populations are severely reduced, craniofacial cartilage is barely detectable, and mbp-positive glial cells are absent in leo1(LA1186) mutants after three days of development. Taken together, these results provide the first genetic evidence of the requirement for Leo1 in the development of the heart and neural crest cell populations.

  9. Gengibre (zingiber officinale roscoe brasileiro: aspectos gerais, óleo essencial e oleoresina. parte 2 - secagem, óleo essencial e oleoresina

    Directory of Open Access Journals (Sweden)

    Mauro Taveira Magalhães

    1997-08-01

    Full Text Available A partir de amostras de gengibre (Zingiber officinale Roscoe do tipo "Gigante", oriundas das diversas localidades produtoras do Brasil, procurou-se estabelecer as melhores condições de processamento e verificar a qualidade do óleo essencial e da oleoresina obtidos. A composição do óleo essencial de gengibre gigante varia de acordo com a técnica de extração e o estado do rizoma. Os óleos essenciais de rizomas frescos e secos foram comparados através de seus índices físico-químicos e composição por CG. São apresentadas as características do óleo essencial do rizoma seco obtido por arraste direto a vapor. Nas oleoresinas obtidas com diferentes solventes determinou-se o teor de óleo essencial. O gengibre comercial brasileiro fornece óleo essencial num rendimento de 2,2% e oleoresina em rendimentos que variam de 6,91-10,90% (etanol, 2,53-5,62% (acetona e 3,35-3,91% (dicloroetano, sendo alternativas interessantes de utilização.

  10. Radiation environment at LEO orbits: MC simulation and experimental data.

    Science.gov (United States)

    Zanini, Alba; Borla, Oscar; Damasso, Mario; Falzetta, Giuseppe

    The evaluations of the different components of the radiation environment in spacecraft, both in LEO orbits and in deep space is of great importance because the biological effect on humans and the risk for instrumentation strongly depends on the kind of radiation (high or low LET). That is important especially in view of long term manned or unmanned space missions, (mission to Mars, solar system exploration). The study of space radiation field is extremely complex and not completely solved till today. Given the complexity of the radiation field, an accurate dose evaluation should be considered an indispensable part of any space mission. Two simulation codes (MCNPX and GEANT4) have been used to assess the secondary radiation inside FO-TON M3 satellite and ISS. The energy spectra of primary radiation at LEO orbits have been modelled by using various tools (SPENVIS, OMERE, CREME96) considering separately Van Allen protons, the GCR protons and the GCR alpha particles. This data are used as input for the two MC codes and transported inside the spacecraft. The results of two calculation meth-ods have been compared. Moreover some experimental results previously obtained on FOTON M3 satellite by using TLD, Bubble dosimeter and LIULIN detector are considered to check the performances of the two codes. Finally the same experimental device are at present collecting data on the ISS (ASI experiment BIOKIS -nDOSE) and at the end of the mission the results will be compared with the calculation.

  11. Beller Lecture: The Roots of Leo Szilard and his Interdisciplinarity

    Science.gov (United States)

    Marx, George

    1998-04-01

    A Central European among the whites was said about Leo Szilard who originated from a polycultural family. In the early 20th century he grew up in Hungary, at the crossroads of history, where political regimes, national borders, ideological doctrines, ``final truths'' changed in a dizzying cavalcade. Instead of conservative dogmatism this social environment required critical thinking in order to survive. World War I was the school of Theodore von Kármán, John von Neumann, Eugene P. Wigner and Leo Szilard; each of them learned trespassing political and disciplinary boundaries without inhibition. Their sensitivity for trends had been utilized by the United States when war efforts and high tech required orientation under new horizons. Szilard's interest ranged from statistical physics through information theory to biological evolution, from life phenomena through hot atoms to nuclear strategy. His intellectual adventures might look crazy jumps for specialists. But now, looking back to the political and technological history of the 20th century one can see than it was a consequent progress of a future-sensitive mind.

  12. An autonomous orbit determination method for MEO and LEO satellite

    Science.gov (United States)

    Zhang, Hui; Wang, Jin; Yu, Guobin; Zhong, Jie; Lin, Ling

    2014-09-01

    A reliable and secure navigation system and assured autonomous capability of satellite are in high demand in case of emergencies in space. This paper introduces a novel autonomous orbit determination method for Middle-Earth-Orbit and Low-Earth-Orbit (MEO and LEO) satellite by observing space objects whose orbits are known. Generally, the geodetic satellites, such as LAGEOS and ETALONS, can be selected as the space objects here. The precision CCD camera on tracking gimbal can make a series of photos of the objects and surrounding stars when MEO and LEO satellite encounters the space objects. Then the information processor processes images and attains sightings and angular observations of space objects. Several clusters of such angular observations are incorporated into a batch least squares filter to obtain an orbit determination solution. This paper describes basic principle and builds integrated mathematical model. The accuracy of this method is analyzed by means of computer simulation. Then a simulant experiment system is built, and the experimental results demonstrate the feasibility and effectiveness of this method. The experimental results show that this method can attain the accuracy of 150 meters with angular observations of 1 arcsecond system error.

  13. Distribution of the GNSS-LEO occultation events over Egypt

    Science.gov (United States)

    Ghoniem, Ibrahim; Mousa, Ashraf El-Kutb; El-Fiky, Gamal

    2017-06-01

    The space-based GNSS RO technique is a promising tool for monitoring the Earth's atmosphere and ionosphere (Mousa et al., 2006). The current paper presents the distribution of the occultation events over Egypt using the operating LEO satellites and GNSS by its two operating systems. By the present research, Egypt could raise NWP Models efficiency by improving meteorological data quality. Twenty operating LEO missions (e.g. Argentinean SAC-C, European MetOp-A, German TerraSAR-X, Indian OceanSat-2, etc.) sent by different countries all over the world were used to derive the occultation events position through Egypt borders by receiving signal from the American global positioning system (GPS) and the Russian global navigation satellite system (GLONASS). Approximately 20,000 km Altitude satellites are transmitting enormous number of rays by the day to approximately 800 km satellites passing by the Earth atmosphere. Our mission is to derive all of these rays position (start and end) by calculating satellites position by the time, determine the rays in the occultation case and derive the atmosphere tangent point position for all occultating rays on the Earth surface (Occultation Events).

  14. An active debris removal parametric study for LEO environment remediation

    Science.gov (United States)

    Liou, J.-C.

    2011-06-01

    Recent analyses on the instability of the orbital debris population in the low Earth orbit (LEO) region and the collision between Iridium 33 and Cosmos 2251 have reignited interest in using active debris removal (ADR) to remediate the environment. There are, however, monumental technical, resource, operational, legal, and political challenges in making economically viable ADR a reality. Before a consensus on the need for ADR can be reached, a careful analysis of its effectiveness must be conducted. The goal is to demonstrate the need and feasibility of using ADR to better preserve the future environment and to explore different operational options to maximize the benefit-to-cost ratio. This paper describes a new sensitivity study on using ADR to stabilize the future LEO debris environment. The NASA long-term orbital debris evolutionary model, LEGEND, is used to quantify the effects of several key parameters, including target selection criteria/constraints and the starting epoch of ADR implementation. Additional analyses on potential ADR targets among the existing satellites and the benefits of collision avoidance maneuvers are also included.

  15. Charging of space debris in the LEO and GEO regions

    Science.gov (United States)

    Sen, Abhijit; Tiwari, Sanat Kumar

    The near exponential rise of space debris at the satellite orbital altitudes (particularly in the low earth orbit (LEO) region) and the risk they pose for space assets is a source of major concern for all nations engaged in space activities. Considerable efforts are therefore being expended into accurate modeling and tracking of these objects and various ideas for the safe removal of these debris are being explored. The debris objects are likely to acquire a large amount of charge since they are typically found in a plasma environment - such as the earth’s ionospheric plasma in the LEO region (100 kms to 1000 kms) and the radiation belts in the geosynchronous orbit (GEO) region. The consequent flow of electron and ion currents on them lead to the accumulation of a large amount of surface charge and the development of a surface potential on these objects. The influence of the plasma environment on the dynamics and charging of the debris is a relatively unexplored area of Space Situational Awareness (SSA) and Space Debris (SD) research and can be potentially important for the accurate prediction of the long-term evolution of debris orbits and their collision probabilities with other space objects. In this paper we will report on the charging of space debris under a variety of orbital conditions in the LEO and GEO regions using both analytic and particle-in-cell (PIC) modeling. The analytic estimates are obtained using refined Orbit Motion Limited (OML) modeling while the simulation studies are carried out using the SPIS code [1]. In the GEO region account is taken of charging due to photoemission processes as well as energetic beam charging. The PIC approach enables us to study charging of irregularly shaped debris objects as well as differential charging on objects that are composed of patches of conducting and insulated regions. The dynamical consequences of the debris charging on their orbital trajectories and rotational characteristics will be discussed. [1] J

  16. Geocenter variations derived from a combined processing of LEO- and ground-based GPS observations

    Science.gov (United States)

    Männel, Benjamin; Rothacher, Markus

    2017-08-01

    GNSS observations provided by the global tracking network of the International GNSS Service (IGS, Dow et al. in J Geod 83(3):191-198, 2009) play an important role in the realization of a unique terrestrial reference frame that is accurate enough to allow a detailed monitoring of the Earth's system. Combining these ground-based data with GPS observations tracked by high-quality dual-frequency receivers on-board low earth orbiters (LEOs) is a promising way to further improve the realization of the terrestrial reference frame and the estimation of geocenter coordinates, GPS satellite orbits and Earth rotation parameters. To assess the scope of the improvement on the geocenter coordinates, we processed a network of 53 globally distributed and stable IGS stations together with four LEOs (GRACE-A, GRACE-B, OSTM/Jason-2 and GOCE) over a time interval of 3 years (2010-2012). To ensure fully consistent solutions, the zero-difference phase observations of the ground stations and LEOs were processed in a common least-squares adjustment, estimating all the relevant parameters such as GPS and LEO orbits, station coordinates, Earth rotation parameters and geocenter motion. We present the significant impact of the individual LEO and a combination of all four LEOs on the geocenter coordinates. The formal errors are reduced by around 20% due to the inclusion of one LEO into the ground-only solution, while in a solution with four LEOs LEO-specific characteristics are significantly reduced. We compare the derived geocenter coordinates w.r.t. LAGEOS results and external solutions based on GPS and SLR data. We found good agreement in the amplitudes of all components; however, the phases in x- and z-direction do not agree well.

  17. Global tracking and inventory of military hardware via LEO satellite: A system approach and likely scenario

    Science.gov (United States)

    Bell, David; Estabrook, Polly; Romer, Richard

    1995-01-01

    A system for global inventory control of electronically tagged military hardware is achievable using a LEO satellite constellation. An equipment Tag can communicate directly to the satellite with a power of 5 watts or less at a data rate of 2400 to 50,000 bps. As examples, two proposed commercial LEO systems, IRIDIUM and ORBCOMM, are both capable of providing global coverage but with dramatically different telecom capacities. Investigation of these two LEO systems as applied to the Tag scenario provides insight into satellite design trade-offs, constellation trade-offs and signal dynamics that effect the performance of a satellite-based global inventory control system.

  18. Fairness based channel borrowing strategy in multimedia LEO satellite communications

    Institute of Scientific and Technical Information of China (English)

    HUANG Fei; XU Hui; WU Shiqi

    2007-01-01

    A novel bandwidth allocation strategy along with a connection admission control technique was proposed to improve the utilization of network resources.It provides the network with better quality-of-service (QoS) guarantees,such as new call blocking probability (CBP) and handoff call dropping probability (CDP) in multimedia low earth orbit (LEO) satellite networks.Simulation results show that,compared with other bandwidth allocation schemes,the proposed scheme offers very low call dropping probability for real-time connections while,at the same time,keeping resource utilization high.Finally we discussed the fairness for the borrowed nonreal-time connections under three different channel borrowing methods.

  19. CLINICOPATHOLOGIC FEATURES OF MAMMARY MASSES IN CAPTIVE LIONS (PANTHERA LEO).

    Science.gov (United States)

    Sadler, Ryan A; Craig, Linden E; Ramsay, Edward C; Helmick, Kelly; Collins, Darin; Garner, Michael M

    2016-03-01

    A multi-institutional retrospective analysis of 330 pathology accessions from 285 different lions found 15 captive, female African lions (Panthera leo) with confirmed mammary masses. Aside from the presence of a mammary mass, the most common initial clinical sign was inappetence. Histologic diagnoses were predominantly adenocarcinoma (n = 12), though two benign masses (mammary hyperplasia and a mammary cyst) and one squamous cell carcinoma were identified. Nine of 13 malignant tumors had metastasized to lymph nodes or viscera at the time of necropsy. Six lions with adenocarcinoma and two lions with benign mammary masses had received hormonal contraception, though little evidence of mammary lobular hyperplasia was seen in association with the adenocarcinomas. The most common concurrent disease processes found at necropsy were chronic urinary tract disease and other malignancies. These cases demonstrate that mammary malignancies occur in captive lions and frequently metastasize.

  20. LEGEND, a LEO-to-GEO Environment Debris Model

    Science.gov (United States)

    Liou, Jer Chyi; Hall, Doyle T.

    2013-01-01

    LEGEND (LEO-to-GEO Environment Debris model) is a three-dimensional orbital debris evolutionary model that is capable of simulating the historical and future debris populations in the near-Earth environment. The historical component in LEGEND adopts a deterministic approach to mimic the known historical populations. Launched rocket bodies, spacecraft, and mission-related debris (rings, bolts, etc.) are added to the simulated environment. Known historical breakup events are reproduced, and fragments down to 1 mm in size are created. The LEGEND future projection component adopts a Monte Carlo approach and uses an innovative pair-wise collision probability evaluation algorithm to simulate the future breakups and the growth of the debris populations. This algorithm is based on a new "random sampling in time" approach that preserves characteristics of the traditional approach and captures the rapidly changing nature of the orbital debris environment. LEGEND is a Fortran 90-based numerical simulation program. It operates in a UNIX/Linux environment.

  1. Next Generation Grating Spectrometer Sounders for LEO and GEO

    Science.gov (United States)

    Pagano, Thomas S.

    2011-01-01

    AIRS and MODIS are widely used for weather, climate, composition, carbon cycle, cross-calibration, and applications. The community asking for new capability in the 2020 timeframe, capabilities desired: (1) Hyperspectral UV to LWIR, High Spatial ?1km IFOV (2) Maximize Synergies of Solar Reflected and IR. Synergies with OCO-2. We expect more users and applications of next gen LEO IR Sounder than GEO. These include: weather, climate, GHG monitoring, aviation, disaster response. There is a new direction for imagers and sounders: (1) Separate Vis/NIR/SWIR from MWIR/LWIR instruments reduces technology risk and complexity. (2) Expect Costs to be lower than CrIS & VIIRS Some additional ideas to reduce costs include: (1) minimum set of requirements (2) mini-grating spectrometers. supports constellation for higher revisit (3) new technology to reduce instrument size (large format fpa's) (4) hosted payloads

  2. Coordinated optical and ultraviolet observations of DH Leo

    Science.gov (United States)

    Newmark, Jeffrey S.; Buzasi, Derek L.; Huenemoerder, David P.; Ramsey, Lawrence W.; Barden, Samuel C.

    1990-01-01

    Results are reported from contemporaneous KPNO optical spectroscopy, IUE UV spectroscopy, and KPNO R photometry of the DH Leo triple system in spring 1987. The data are presented in tables, graphs, and spectral phase images and discussed in detail. The H-alpha, H-beta, H-gamma, H-delta, and Ca II H and IRT lines are found to have excess emission, and the phase modulation in H-alpha, H-beta, and Ca II is well correlated with the photometric modulation. This result is attributed to the combination of (1) a small amount of global chromospheric emission and (2) emission from plagelike regions associated with cool starspots. The (H-alpha)/(H-beta) ratio is found to be significantly lower than that in longer-period RS CVn systems.

  3. New Results on RZ Leo and CC Scl

    Science.gov (United States)

    Szkody, Paula; Mukadam, Anjum S.; Gaensicke, Boris T.; Toloza, Odette; Dai, Zhibin; HST GO12870 Team

    2017-01-01

    Using HST COS ultraviolet spectra in time-tag mode and a long K2 observation, we have determined a spin period for the white in RZ Leo of 220 seconds, thus confirming this cataclysmic variable as a new member of the Intermediate Polar class of systems. The ultraviolet light curve of CC Scl at quiescence created from its COS spectral observations is dominated by its spin period of 195 seconds (that has only been previously observed during one of its outbursts). Spectra formed from the high and low sections of its light curve shows a temperature difference of several thousand degrees.PS and ASM acknowledge support from NASA grant HST-GO13807 and from NSF grant AST-1514737.

  4. LEO 卫星通信网络的移动性管理%Mobility management in LEO satellite communication networks

    Institute of Scientific and Technical Information of China (English)

    贺达健; 游鹏; 雍少为

    2016-01-01

    近年来,低轨道(Low Earth Orbit,LEO)卫星通信网络以全球覆盖、低传输时延、低功耗链路、较强的抗毁性等特点而受到广泛关注,是未来全球移动通信系统的重要组成部分。移动性管理是构建 LEO 卫星通信网络的关键技术,为推动移动性管理问题的研究,文章从 LEO 卫星通信网络的结构和特点入手,阐述了 LEO 卫星通信网络中移动性管理的分类,并分析了其相比地面移动无线网络的特殊性。从链路层、网络层、传输层三个协议层次综述了近年来 LEO 卫星通信网络移动性管理研究的国内外现状,重点介绍了移动 IPv6(Mobile IPv6,MIPv6)和无缝 IP 分集通用移动性结构(Seamless IP-diversity based Generalized Mobility Architecture,SIGMA)在 LEO 卫星通信网络中的应用。最后,指出了移动性管理的发展趋势。%In recent years,low Earth orbit (LEO)satellite communication networks attract a lot of researchers'attention for its global coverage,short propagation delay,low-power links and great invulnerabi lity performance,etc. It wi ll be an important part of the future global mobi le communication systems.Mobi lity management is a key technology for enabling service in LEO satellite communication networks.The characteristics, research status and problems of mobi lity management were analyzed.Fi rstly,a brief classification of mobi lity management of LEO satellite communications networks was provided and characteristics distinguished from terrestrial mobi lity wi reless networks were analyzed based on the architecture and features of LEO satellite communication networks. Then the state-of-the-art mobi lity management schemes in LEO satellite communication networks were summarized from link layer,network layer and transport layer.A detai led description of the application of MIPv6 and SIGMA in LEO satellite envi ronment was given. Finally,some trends of mobi lity management of LEO satellite communications networks

  5. Archean evolution of the Leo Rise and its Eburnean reworking

    Science.gov (United States)

    Thiéblemont, Denis; Goujou, Jean Christian; Egal, Emmanuel; Cocherie, Alain; Delor, Claude; Lafon, Jean Michel; Fanning, C. Mark

    2004-06-01

    Recent geological mapping in southeastern Guinea, supported by zircon dating, has called into question traditional understanding concerning the evolution of the Leo Rise. Gneiss dated at about 3540 Ma appears to constitute the earliest evidence for continental accretion within the Leo Rise. The existence of a Leonian depositional cycle at about 3000 Ma is confirmed, marked by volcanic and sedimentary rocks that can be correlated with the Loko Group in Sierra Leone. The span of ages (3244-3050 Ma) suggests that the Leonian cycle comprises different episodes whose respective chronology is as yet uncertain. Clearly distinct from the Leonian cycle, the Liberian cycle (˜2900-2800 Ma) is represented in Guinea by granite and migmatite (˜2910-2800 Ma), reflecting remobilization of the ancient Archean basement and deformation of the Leonian rocks; no deposition is associated with this cycle. After the Liberian, the Nimba and Simandou successions, containing Liberian detrital zircons, are assigned to the Birimian (˜2200-2000 Ma). Finally, Eburnean tectonism caused intense deformation of the Archean craton, accompanied by high-grade metamorphism and the intrusion of granite and syenite with ages between 2080 and 2020 Ma. The evolution of the Kénéma-Man domain, attributed to the cumulated effect of the Leonian and Liberian cycles, is thus in part Eburnean. We can suppose, therefore, that the NNE-SSW-trending structures attributed to the Liberian in Sierra Leone are, in fact, Eburnean. The Kambui Supergroup, also affected by this tectonism, should thus be assigned to the Birimian rather than the Liberian, which would explain its similarities with the Nimba and Simandou successions.

  6. The Arecibo Legacy Fast ALFA Survey: IX. The Leo Region HI Catalog, Group Membership and the HI Mass Function for the Leo I Group

    CERN Document Server

    Stierwalt, S; Giovanelli, R; Kent, B R; Martin, A M; Saintonge, A; Karachentsev, I D; Karachentseva, V E

    2009-01-01

    We present the catalog of HI sources extracted from the ongoing Arecibo Legacy Fast ALFA (ALFALFA) extragalactic HI line survey, found within the sky region bounded by 9h36m < RA < 11h36m and +08deg < DEC < +12deg. The HI catalog presented here for this 118-deg^2 region is combined with ones derived from surrounding regions also covered by the ALFALFA survey to examine the large scale structure in the complex Leo region. Because of the combination of wide sky coverage and superior sensitivity, spatial and spectral resolution, the ALFALFA HI catalog of the Leo region improves significantly on the numbers of low HI mass sources as compared with those found in previous HI surveys. The HI mass function of the Leo I group presented here is dominated by low-mass objects: 45 of the 65 Leo I members have M_HI < 10^8 Msun, yielding tight constraints on the low-mass slope of the Leo I HI mass function. The best-fit slope is alpha < -1.41 + 0.2 - 0.1. A direct comparison between the ALFALFA HI line det...

  7. Haal alles uit onderzoek (interview met Leo Marcelis en Hans Dagevos)

    NARCIS (Netherlands)

    Kamminga, H.; Marcelis, L.F.M.; Dagevos, H.

    2012-01-01

    In de toekomst zullen tuinbouwbedrijven meer teelt- en consumentenonderzoek op eigen houtje laten uitvoeren. Voor veel ondernemers is dit nieuw. Wetenschappers Leo Marcelis en Hans Dagevos geven tips om zoveel mogelijk nuttige informatie uit onderzoek te halen.

  8. The semantics of greeting and leavetaking in Leo Tolstoy's «Anna Karenina»

    OpenAIRE

    Lebedeva, A.

    2010-01-01

    The article deals with the non-verbal analogues of greeting and leave-taking which are supposed to be etiquette speech genres in situations of communication. The subject of research is Leo Tolstoy's «Anna Karenina».

  9. Leo Piilonen appointed William E. Hassinger, Jr. Senior Faculty Fellow in Physics

    OpenAIRE

    Owczarski, Mark

    2010-01-01

    Leo Piilonen, professor of physics in the College of Science at Virginia Tech, was recently appointed the William E. Hassinger, Jr., Senior Faculty Fellow in Physics by the Virginia Tech Board of Visitors.

  10. Narratiivsuse probleem kaasaaegses arhitektuurihistoriograafias : Mõned võimalused Leo Gensi arhitektuurikirjutuse lugemiseks / Epp Lankots

    Index Scriptorium Estoniae

    Lankots, Epp, 1976-

    2010-01-01

    Käsitletakse 20. sajandi moodsa arhitektuuri ajaloo tekstide lugemisvõimalusi kriitilise historiograafia valguses. Vaadeldakse Leo Gensi kui peamise nõukogudeaegsest arhitektuurist kirjutanud ajaloolase ja kriitiku tekstistrateegiaid. Ka tema ajalootekstide võrdlusi tunduvalt teravamate ajakirjanduslike tekstidega

  11. THE SEMANTICS OF GREETING AND LEAVETAKING IN LEO TOLSTOY'S «ANNA KARENINA»

    OpenAIRE

    LEBEDEVA A.

    2010-01-01

    The article deals with the non-verbal analogues of greeting and leave-taking which are supposed to be etiquette speech genres in situations of communication. The subject of research is Leo Tolstoy's «Anna Karenina».

  12. The Many Worlds of Leo Szilard: Physicist, Peacemaker, Provocateur

    Science.gov (United States)

    Lanouette, William

    2014-03-01

    Best known for being the first to conceive and patent the nuclear chain reaction in the 1930s, Leo Szilard should also be remembered for other insights in both physics and biology, and for historical initiatives to control the A-bomb he helped create. In physics, Szilard applied entropy to data in a seminal 1929 paper that laid the basis for ``information theory.'' Szilard co-designed an electromagnetic refrigerator pump with Einstein in the 1920s, in 1939 he co-designed the first nuclear reactor with Enrico Fermi, and he later thought up and named the nuclear ``breeder'' reactor. Biologist Francois Jacob called Szilard an ``intellectual bumblebee'' for the many novel ideas he shared, including one that earned Jacob and others the Nobel Prize. James D. Watson said that for intellectual stimulation he liked being around Szilard because ``Leo got excited about something before it was true.'' A political activist, Szilard proposed and drafted the 1939 letter Einstein sent to President Franklin Roosevelt that warned of German A-bomb work and led to the Manhattan Project - where Szilard was ``Chief Physicist.'' Yet Szilard then worked tirelessly to curb nuclear weapons, organizing a scientists' petition to President Truman and lobbying Congress for civilian control of the atom. Szilard loved dreaming up new institutions. He helped to create the Pugwash Conferences on Science and World Affairs, and founded the Council for a Livable World - the first political action committee for arms control. In biology, Szilard proposed the European Molecular Biology Organization modeled on CERN, and helped create the Salk Institute for Biological Studies, where he was one of the first fellows. Shy, witty, and eccentric, Szilard wrote a political satire in 1960 that predicted when the US-Soviet nuclear arms race would end in the late 1980s. Another satire, ``My Trial as a War Criminal'' about scientists' responsibilities for weapons of mass destruction, is credited with prompting

  13. THE SPACE MOTION OF LEO I: HUBBLE SPACE TELESCOPE PROPER MOTION AND IMPLIED ORBIT

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Sangmo Tony; Van der Marel, Roeland P. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Besla, Gurtina [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Boylan-Kolchin, Michael; Bullock, James S. [Department of Physics and Astronomy, Center for Cosmology, University of California, 4129 Reines Hall, Irvine, CA 92697 (United States); Majewski, Steven R., E-mail: tsohn@stsci.edu [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States)

    2013-05-10

    We present the first absolute proper motion measurement of Leo I, based on two epochs of Hubble Space Telescope ACS/WFC images separated by {approx}5 years in time. The average shift of Leo I stars with respect to {approx}100 background galaxies implies a proper motion of ({mu}{sub W}, {mu}{sub N}) = (0.1140 {+-} 0.0295, -0.1256 {+-} 0.0293) mas yr{sup -1}. The implied Galactocentric velocity vector, corrected for the reflex motion of the Sun, has radial and tangential components V{sub rad} = 167.9 {+-} 2.8 km s{sup -1} and V{sub tan} = 101.0 {+-} 34.4 km s{sup -1}, respectively. We study the detailed orbital history of Leo I by solving its equations of motion backward in time for a range of plausible mass models for the Milky Way (MW) and its surrounding galaxies. Leo I entered the MW virial radius 2.33 {+-} 0.21 Gyr ago, most likely on its first infall. It had a pericentric approach 1.05 {+-} 0.09 Gyr ago at a Galactocentric distance of 91 {+-} 36 kpc. We associate these timescales with characteristic timescales in Leo I's star formation history, which shows an enhanced star formation activity {approx}2 Gyr ago and quenching {approx}1 Gyr ago. There is no indication from our calculations that other galaxies have significantly influenced Leo I's orbit, although there is a small probability that it may have interacted with either Ursa Minor or Leo II within the last {approx}1 Gyr. For most plausible MW masses, the observed velocity implies that Leo I is bound to the MW. However, it may not be appropriate to include it in models of the MW satellite population that assume dynamical equilibrium, given its recent infall. Solution of the complete (non-radial) timing equations for the Leo I orbit implies an MW mass M{sub MW,vir} = 3.15{sub -1.36}{sup +1.58} x 10{sup 12} M{sub Sun }, with the large uncertainty dominated by cosmic scatter. In a companion paper, we compare the new observations to the properties of Leo I subhalo analogs extracted from cosmological

  14. Cistos peribiliares em leão-africano (Panthera leo

    Directory of Open Access Journals (Sweden)

    Ricardo B. Lucena

    2011-02-01

    Full Text Available São descritos os achados macroscópicos e histopatológicos de cistos peribiliares em uma fêmea adulta de leão-africano (Panthera leo. Macroscopicamente, todos os lobos hepáticos continham numerosos cistos preenchidos por líquido translúcido. Histologicamente, os cistos estavam localizados no hilo hepático e nos tratos portais. Os cistos eram revestidos internamente por epitélio simples, constituído por células colunares ou cuboidais e não mucinosas, de acordo com avaliação para ácido periódico de Schiff/azul alciano. Na imuno-histiquímica, todas as células desse epitélio foram positivas para citoceratina. O leão morreu de complicações relacionadas a um carcinoma pulmonar e não foram observadas alterações clínicas associadas à lesão hepática, comprovando que cistos peribiliares em leões também ocorrem não associados a sinais clínicos.

  15. The EUVE point of view of AD Leo

    CERN Document Server

    Sanz-Forcada, J

    2002-01-01

    All the Extreme Ultraviolet Explorer (EUVE) observations of AD Leo, totalling 1.1 Ms of exposure time, have been employed to analyze the corona of this single M dwarf. The light curves show a well defined quiescent stage, and a distribution of amplitude of variability following a power law with a ~-2.4 index. The flaring behavior exhibits much similarity with other M active stars like FK Aqr or YY Gem, and flares behave differently from late type active giants and subgiants. The Emission Measure Distribution (EMD) of the summed spectrum, as well as that of quiescent and flaring stages, were obtained using a line-based method. The average EMD is dominated by material at log T(K)~6.9, with a second peak around log T(K)~6.3, and a large increase in the amount of material with log T(K)>~7.1 during flares, material almost absent during quiescence. The results are interpreted as the combination of three families of loops with maximum temperatures at log T(K)~6.3, ~6.9 and somewhere beyond log T(K)>~7.1. A value of ...

  16. Leo Esakia on duality in modal and intuitionistic logics

    CERN Document Server

    Bezhanishvili, Guram

    2014-01-01

    This volume is dedicated to Leo Esakia's contributions to the theory of modal and intuitionistic systems. Consisting of 10 chapters, written by leading experts, this volume discusses Esakia's original contributions and consequent developments that have helped to shape duality theory for modal and intuitionistic logics and to utilize it to obtain some major results in the area. Beginning with a chapter which explores Esakia duality for S4-algebras, the volume goes on to explore Esakia duality for Heyting algebras and its generalizations to weak Heyting algebras and implicative semilattices. The book also dives into the Blok-Esakia theorem and provides an outline of the intuitionistic modal logic KM which is closely related to the Gödel-Löb provability logic GL. One chapter scrutinizes Esakia's work interpreting modal diamond as the derivative of a topological space within the setting of point-free topology. The final chapter in the volume is dedicated to the derivational semantics of modal logic and other re...

  17. A Search for Dust Emission in the Leo Intergalactic Cloud

    CERN Document Server

    Bot, C; Latter, W B; Puget, J; Schneider, S; Terzian, Y

    2009-01-01

    We present a search for infrared dust emission associated with the Leo cloud, a large intergalactic cloud in the M96 group. Mid-infrared and far-infrared images were obtained with IRAC and MIPS on the Spitzer Space Telescope. Our analysis of these maps is done at each wavelength relative to the HI spatial distribution. We observe a probable detection at 8 microns and a marginal detection at 24 microns associated with the highest HI column densities in the cloud. At 70 and 160 microns, upper limits on the dust emission are deduced. The level of the detection is low so that the possibility of a fortuitous cirrus clump or of an overdensity of extragalactic sources along the line of sight can not be excluded. If this detection is confirmed, the quantities of dust inferred imply a dust to gas ratio in the intergalactic cloud up to a few times solar but no less than 1/20 solar. A confirmed detection would therefore exclude the possibility that the intergalactic cloud has a primordial origin. Instead, this large int...

  18. Simulation of the Impacts of Single LEO Satellite Orbit Parameters on the Distribution and Number of Occultation Events

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Focusing on carrying out GPS occultation observations with a receiver set on LEO satellite, this paper develops the LEO orbit simulation system based on which the occultation events can be simulated taking into account the geometric relationship of the satellites and the field of view of the receiver antenna. In this paper, the impacts of 4 types of LEO orbit parameters including argument of latitude (AOL), right ascension of ascending node (RAAN), orbit height and orbit inclination on the distribution and number of occultation events observed with a single LEO satellite are discussed through simulation and some conclusions are drawn.

  19. Space-based visible observation strategy for beyond-LEO objects based on an equatorial LEO satellite with multi-sensors

    Science.gov (United States)

    Hu, Yun-peng; Huang, Jian-yu; Chen, Lei

    2017-04-01

    Many space-based visible observation strategies based on Low Earth Orbit (LEO) satellites for observing Geosynchronous Orbit (GEO) objects were proposed previously. However, there were few studies about other beyond-LEO objects (Geostationary Transfer Orbit (GTO) objects, Medium Earth Orbit (MEO) objects, and Molniya objects). In this paper, a space-based visible observation strategy is proposed for observing GEO objects, GTO objects, MEO objects (especially global navigation satellites), and Molniya objects simultaneously to get more orbital data, using an earth-oriented equatorial LEO satellite with three sensors. This work is focused on the pointing geometry. Brightness of observed objects and sensitivity of sensors are assumed under the relative ideal conditions. First, the distribution characteristics of these beyond-LEO objects are discussed. And in order to observe global navigation satellites efficiently, joint regions formed by the track superposition of two adjacent orbits in a constellation are proposed. To offset the influence of the earth shadow and constraint of sun-target-observer angle, two sensors pointing inside of the equatorial plane are used to observe GEO and GTO objects. The installation angle of the third sensor is optimized to obtain a relative high coverage rate for observing global navigation satellites and Molniya objects based on joint regions. Finally, the coverage rate, the number of observations, and observation duration under different sensors with different field of views (FOVs) are compared and analyzed respectively.

  20. Desempenho de um trator agrícola de pneus, funcionando com misturas de óleo diesel e óleo de soja reutilizado

    Directory of Open Access Journals (Sweden)

    Wagner da Cunha Siqueira

    2011-10-01

    Full Text Available No Brasil, a forma de energia alternativa mais atraente tem sido a biomassa e, mais recentemente, os óleos vegetais residuais e in natura. Portanto, objetivou-se, com este trabalho, avaliar o desempenho na tomada de potência de um trator agrícola de pneus, utilizando misturas de óleo Diesel (OD com óleo de soja reutilizádo (OSR. Primeiramente, foi realizado um estudo de densidade das misturas, comportamento da temperatura do óleo Diesel no sistema de alimentação de combustível do motor e análises de viscosidades das misturas em estudo. Após as análises, verificou-se, por meio de ensaios dinamométricos, o desempenho do motor alimentado com misturas de OD com OSR, em diferentes proporções. As principais conclusões deste trabalho foram: a para as avaliações na tomada de potência, a mistura de 25% OD com 75% OSR apresentou a maior potência entre as demais misturas; b o consumo especifico e os torques demonstraram tendência a maiores valores com o acréscimo da percentagem de OSR às misturas.

  1. Morfometria testicular de cabritos alimentados com óleo de licuri (Syagrus coronata

    Directory of Open Access Journals (Sweden)

    L.P. Barbosa

    2012-08-01

    Full Text Available Determinou-se o desenvolvimento testicular de caprinos pré-púberes alimentados com óleo de licuri (Syagrus coronata na dieta. Foram utilizados 19 cabritos ¾ Boer, recém-desmamados, com média de idade de três meses. Os animais, submetidos a um período de 75 dias de confinamento, receberam alimentação composta por: farelo de milho, farelo de soja, feno picado de tifton 85 e de óleo de licuri com base na matéria seca. Os animais foram distribuídos em quatro grupos: sem lipídio adicional (n= 5; com 1,5% de óleo de licuri (n= 5; com 3,0% de óleo de licuri (n= 5; e com 4,5% de óleo de licuri (n= 4. As avaliações de peso corporal e de biometria testicular foram realizadas quinzenalmente. Após o período de confinamento, os animais foram abatidos para determinação do peso dos testículos, peso dos epidídimos e índice gonadossomático. A adição de óleo de licuri em até 4,5% na dieta de caprinos pré-púberes não alterou o desenvolvimento testicular com base nas características da biometria e morfometria testicular, indicando que a inclusão de até 4,5% de óleo de licuri na dieta pode ser utilizada.

  2. THE STAR FORMATION HISTORY OF LEO T FROM HUBBLE SPACE TELESCOPE IMAGING

    Energy Technology Data Exchange (ETDEWEB)

    Weisz, Daniel R.; Dalcanton, Julianne J.; Gilbert, Karoline M.; Williams, Benjamin F. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Zucker, Daniel B. [Department of Physics and Astronomy, Macquarie University, Sydney 2109 (Australia); Dolphin, Andrew E. [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Martin, Nicolas F. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); De Jong, Jelte T. A. [Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 Leiden (Netherlands); Holtzman, Jon A. [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger St., Las Cruces, NM 88003 (United States); Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 (United States); Belokurov, Vasily; Evans, N. Wyn, E-mail: dweisz@astro.washington.edu [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)

    2012-04-01

    We present the star formation history (SFH) of the faintest known star-forming galaxy, Leo T, based on deep imaging taken with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2). The HST/WFPC2 color-magnitude diagram (CMD) of Leo T is exquisitely deep, extending {approx}2 mag below the oldest main-sequence turnoff, permitting excellent constraints on star formation at all ages. We use a maximum likelihood CMD fitting technique to measure the SFH of Leo T assuming three different sets of stellar evolution models: Padova (solar-scaled metallicity) and BaSTI (both solar-scaled and {alpha}-enhanced metallicities). The resulting SFHs are remarkably consistent at all ages, indicating that our derived SFH is robust to the choice of stellar evolution model. From the lifetime SFH of Leo T, we find that 50% of the total stellar mass formed prior to z {approx} 1 (7.6 Gyr ago). Subsequent to this epoch, the SFH of Leo T is roughly constant until the most recent {approx}25 Myr, where the SFH shows an abrupt drop. This decrease could be due to a cessation of star formation or stellar initial mass function sampling effects, but we are unable to distinguish between the two scenarios. Overall, our measured SFH is consistent with previously derived SFHs of Leo T. However, the HST-based solution provides improved age resolution and reduced uncertainties at all epochs. The SFH, baryonic gas fraction, and location of Leo T are unlike any of the other recently discovered faint dwarf galaxies in the Local Group, and instead bear strong resemblance to gas-rich dwarf galaxies (irregular or transition), suggesting that gas-rich dwarf galaxies may share common modes of star formation over a large range of stellar mass ({approx}10{sup 5}-10{sup 9} M{sub Sun }).

  3. Study of LEO-SAT microwave link for broad-band mobile satellite communication system

    Science.gov (United States)

    Fujise, Masayuki; Chujo, Wataru; Chiba, Isamu; Furuhama, Yoji; Kawabata, Kazuaki; Konishi, Yoshihiko

    1993-01-01

    In the field of mobile satellite communications, a system based on low-earth-orbit satellites (LEO-SAT's) such as the Iridium system has been proposed. The LEO-SAT system is able to offer mobile telecommunication services in high-latitude areas. Rain degradation, fading and shadowing are also expected to be decreased when the system is operated at a high elevation angle. Furthermore, the propagation delay generated in the LEO-SAT system is less pronounced than that in the geostationary orbit satellite (GEO-SAT) system and, in voice services, the effect of the delay is almost negligible. We proposed a concept of a broad-band mobile satellite communication system with LEO-SAT's and Optical ISL. In that system, a fixed L-band (1.6/1.5 GHz) multibeam is used to offer narrow band service to the mobile terminals in the entire area covered by a LEO-SAT and steerable Ka-band (30/20 GHz) spot beams are used for the wide band service. In this paper, we present results of a study of LEO-SAT microwave link between a satellite and a mobile terminal for a broad-band mobile satellite communication system. First, the results of link budget calculations are presented and the antennas mounted on satellites are shown. For a future mobile antenna technology, we also show digital beamforming (DBF) techniques. DBF, together with modulation and/or demodulation, is becoming a key technique for mobile antennas with advanced functions such as antenna pattern calibration, correction, and radio interference suppression. In this paper, efficient DBF techniques for transmitting and receiving are presented. Furthermore, an adaptive array antenna system suitable for this LEO-SAT is presented.

  4. PROPRIEDADES DE ÓLEOS EMPREGADOS EM FLOTAÇÃO

    Directory of Open Access Journals (Sweden)

    José Aurélio Medeiros da Luz

    2014-07-01

    Full Text Available Neste trabalho se buscou a sistematização das características de quatro amostras de óleos vegetais e uma amostra de sebo bovino, no que concerne a suas propriedades físico-químicas como com o fito de estabelecer padrões de comportamento e de desempenho em sistemas de flotação. Os óleos vegetais estudados foram: de arroz refinado, de rícino, de semente de uva e de soja refinado, usualmente empregados em operações de tecnologia mineral, com ênfase em seu uso em sistemas de flotação em espuma. As massas específicas determinadas foram: 930 kg/m³ para o óleo de semente de uva; 950 kg/m³ para o óleo de rícino; 910 kg/m³ para o óleo de arroz refinado; e 920 kg/m³ para o óleo de soja. Quanto à tensão superficial foram realizados 26 ensaios para cada amostra de óleo vegetal sendo que os valores variam de 0,0323 N/m a 0,0334 N/m. Viscosidade dinâmica aparente, tensão superficial, índice de refração e valores de umidade também foram levantados. Os resultados permitiram aceder às propriedades das amostras e confrontá-las com as que se descrevem na literatura, servindo, assim, como subsidio ao entendimento da influência destas propriedades na flotação.

  5. Óleo de melaleuca (Melaleuca alternifolia Maiden & Betche, Cheel no controle de cercosporiose em beterraba

    Directory of Open Access Journals (Sweden)

    A.D. SOUZA

    2015-01-01

    Full Text Available RESUMO O óleo volátil da melaleuca (Melaleuca alternifolia Maiden & Betche, Cheel possui atividade antimicrobiana podendo causar efeitos sobre as plantas. Avaliou-se a inibição do óleo em Cercospora beticolaSacc., e seu efeito no aumento da produção e qualidade de raízes de beterraba. As doses foram de 0,13; 0,67; 0,80 e 1,00% do óleo, além das testemunhas composta pelo meio de cultura Batata Dextrose Ágar (BDA no experimento in vitro, e água no experimento in vivo. As plantas foram pulverizadas duas vezes por semana. O delineamento foi inteiramente casualizado, com 4 repetições, e as médias foram comparadas pelo teste Tukey a 5% de probabilidade. O índice de infecção das folhas foi determinado por escala diagramática além do peso e diâmetro das raízes. Os resultados de inibição do crescimento micelial para as doses do óleo foram 0; 56; 87; 83 e 99%, e os índices de infecção: 77,08; 35,62; 21,04; 19,37 e 20,00%, respectivamente, para a testemunha e as doses 0,13; 0,67; 0,80 e 1,00% do óleo. Somente na concentração de 0,80% o óleo proporcionou relação positiva entre o ganho de peso e o diâmetro das raízes. O óleo de Melaleuca foi eficaz no controle de C. beticola e, como consequência, houve produção de raízes de beterraba com melhor desenvolvimento.

  6. An Abel transform for deriving line-of-sight wind profiles from LEO-LEO infrared laser occultation measurements

    Science.gov (United States)

    Syndergaard, S.; Kirchengast, G.

    2016-03-01

    We have developed a formula for the retrieval of the line-of-sight (l.o.s.) wind speed from future low Earth orbit (LEO) satellite-to-satellite infrared laser occultation measurements. The formula involves an Abelian integral transform akin to the Abel transform widely used for deriving refractive index from bending angle in Global Navigation Satellite System radio occultation measurements. Besides the Abelian integral transform, the formula is derived from a truncated series expansion of the volume absorption coefficient as a function of frequency and includes a simple absorption-line-asymmetry correction term. A first-order formulation (referred to as the standard formula) is complemented by higher-order terms that can be used for high-accuracy computations. Under the assumptions of spherical symmetry and perfect knowledge of spectroscopy, the residual l.o.s. wind error from using the standard formula rather than the high-accuracy formula is assessed to be small compared to that anticipated from measurement errors in a real experiment. Applying the new formula just in standard form to future infrared laser transmission profiles would therefore enable the retrieval of l.o.s. stratospheric wind profiles with an accuracy limited mainly by measurement errors, residual spectroscopic errors, and deviations from spherical symmetry.

  7. Leo P: A very low-mass, extremely metal-poor, star-forming galaxy

    Science.gov (United States)

    McQuinn, Kristen B.; Leo P Team

    2017-01-01

    Leo P is a low-luminosity dwarf galaxy just outside the Local Group with properties that make it an ideal probe of galaxy evolution at the faint-end of the luminosity function. Using combined data from 2 Hubble Space Telescope (HST) observing campaigns, the Very Large Array, the Spitzer Space telescope, as well as ground based data, we have constructed a robust evolutionary picture of Leo P. Leo P is one the most metal-poor, gas-rich galaxies ever discovered, has a stellar mass of a 5x105 Msun, comparable gas mass, and a single HII region. The star formation history reconstructed from the resolved stellar populations in Leo P shows it is unquenched, despite its very low mass. Based on the star formation history and metallicity measurements, the galaxy has lost 95% of its oxygen produced via nucleosynthesis, presumably to outflows. The neutral gas in the galaxy shows signs of rotation, although the velocity dispersion is comparable to the rotation velocity. Thus, Leo P bridges the gap between more massive dwarf irregular and less massive dwarf spheroidals on the baryonic Tully-Fisher relation. Furthermore, the galaxy hosts several, extremely dusty AGB candidates which will be probed with new HST and Spitzer observations. If confirmed as AGB stars, these may be our best local proxies for studying chemically unevolved star formation and subsequent dust production in metallicity environments comparable to the early universe.

  8. Dynamical evidence for a strong tidal interaction between the Milky Way and its satellite, Leo V

    CERN Document Server

    Collins, Michelle L M; Sand, David J; Bonaca, Ana; Willman, Beth; Strader, Jay

    2016-01-01

    We present a chemodynamical analysis of the Leo~V dwarf galaxy, based on Keck II DEIMOS spectra of 8 member stars. We find a systemic velocity for the system of $\\langle v_r\\rangle = 170.9^{+ 2.1}_{-1.9}$kms$^{-1}$, and barely resolve a velocity dispersion for the system, with $\\sigma_{vr} = 2.3^{+3.2}_{-1.6}$kms$^{-1}$, consistent with previous studies of Leo~V. The poorly resolved dispersion means we are unable to concretely determine whether Leo~V is dark matter dominated. We find an average metallicity for the dwarf of [Fe/H]$ = -2.48\\pm0.21$, and measure a significant spread in the iron abundance of its member stars, with $-3.1\\le$[Fe/H]$\\le-1.9$ dex, which cleanly identifies Leo~V as a dwarf galaxy that has been able to self-enrich its stellar population through extended star formation. Owing to the tentative photometric evidence for tidal substructure around Leo~V, we also investigate whether there is any dynamical evidence for tidal stripping or shocking of the system. We measure a significant velocit...

  9. The Space Motion of Leo I: Hubble Space Telescope Proper Motion and Implied Orbit

    CERN Document Server

    Sohn, Sangmo Tony; van der Marel, Roeland P; Boylan-Kolchin, Michael; Majewski, Steven R; Bullock, James S

    2012-01-01

    We present the first absolute proper motion measurement of Leo I, based on two epochs of HST ACS/WFC images separated by ~5 years. The average shift of Leo I stars with respect to ~100 background galaxies implies a proper motion of (mu_W, mu_N) = (0.1140 +/- 0.0295, -0.1256 +/- 0.0293) mas/yr. The implied Galactocentric velocity vector, corrected for the reflex motion of the Sun, has radial and tangential components V_rad = 167.9 +/- 2.8 km/s and V_tan = 101.0 +/- 34.4 km/s, respectively. We study the detailed orbital history of Leo I by solving its equations of motion backward in time for a range of plausible mass models for the Milky Way and its surrounding galaxies. Leo I entered the Milky Way virial radius 2.33 +/- 0.21 Gyr ago, most likely on its first infall. It had a pericentric approach 1.05 +/- 0.09 Gyr ago at a Galactocentric distance of 91 +/- 36 kpc. We associate these time scales with characteristic time scales in Leo I's star formation history, which shows an enhanced star formation activity ~2 ...

  10. The Star Formation History of Leo T from Hubble Space Telescope Imaging

    CERN Document Server

    Weisz, Daniel R; Dolphin, Andrew E; Martin, Nicolas F; de Jong, Jelte T A; Holtzman, Jon A; Dalcanton, Julianne J; Gilbert, Karoline M; Williams, Benjamin F; Bell, Eric F; Belokurov, Vasily; Evans, N Wyn

    2012-01-01

    We present the star formation history (SFH) of the faintest known star-forming galaxy, Leo T, based on imaging taken with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2). The HST/WFPC2 color-magnitude diagram (CMD) of Leo T is exquisitely deep, extending ~ 2 magnitudes below the oldest main sequence turnoff, permitting excellent constraints on star formation at all ages. We use a maximum likelihood CMD fitting technique to measure the SFH of Leo T assuming three different sets of stellar evolution models: Padova (solar-scaled metallicity) and BaSTI (both solar-scaled and alpha-enhanced metallicities). The resulting SFHs are remarkably consistent at all ages, indicating that our derived SFH is robust to the choice of stellar evolution model. From the lifetime SFH of Leo T, we find that 50% of the total stellar mass formed prior to z ~ 1 (7.6 Gyr ago). Subsequent to this epoch, the SFH of Leo T is roughly constant until the most recent ~ 25 Myr, where the SFH shows an abrupt drop. This de...

  11. LEO1 is regulated by PRL-3 and mediates its oncogenic properties in acute myelogenous leukemia.

    Science.gov (United States)

    Chong, Phyllis S Y; Zhou, Jianbiao; Cheong, Lip-Lee; Liu, Shaw-Cheng; Qian, Jingru; Guo, Tiannan; Sze, Siu Kwan; Zeng, Qi; Chng, Wee Joo

    2014-06-01

    PRL-3, an oncogenic dual-specificity phosphatase, is overexpressed in 50% of acute myelogenous leukemia (AML) and associated with poor survival. We found that stable expression of PRL-3 confers cytokine independence and growth advantage of AML cells. However, how PRL-3 mediates these functions in AML is not known. To comprehensively screen for PRL3-regulated proteins in AML, we performed SILAC-based quantitative proteomics analysis and discovered 398 significantly perturbed proteins after PRL-3 overexpression. We show that Leo1, a component of RNA polymerase II-associated factor (PAF) complex, is a novel and important mediator of PRL-3 oncogenic activities in AML. We described a novel mechanism where elevated PRL-3 protein increases JMJD2C histone demethylase occupancy on Leo1 promoter, thereby reducing the H3K9me3 repressive signals and promoting Leo1 gene expression. Furthermore, PRL-3 and Leo1 levels were positively associated in AML patient samples (N=24; PPRL-3 oncogenic phenotypes in AML. Loss of Leo1 leads to destabilization of the PAF complex and downregulation of SOX2 and SOX4, potent oncogenes in myeloid transformation. In conclusion, we identify an important and novel mechanism by which PRL-3 mediates its oncogenic function in AML.

  12. An Assessment of the Current LEO Debris Environment and the Need for Active Debris Removal

    Science.gov (United States)

    Liou, Jer-Chyi

    2010-01-01

    The anti-satellite test on the Fengun-1 C weather satellite in early 2007 and the collision between Iridium 33 and Cosmos 2251 in 2009 dramatically altered the landscape of the human-made orbital debris environment in the low Earth orbit (LEO). The two events generated approximately 5500 fragments large enough to be tracked by the U.S. Space Surveillance Network. Those fragments account for more than 60% increase to the debris population in LEO. However, even before the ASAT test, model analyses already indicated that the debris population (for those larger than 10 cm) in LEO had reached a point where the population would continue to increase, due to collisions among existing objects, even without any future launches. The conclusion implies that as satellites continue to be launched and unexpected breakup events continue to occur, commonly-adopted mitigation measures will not be able to stop the collision-driven population growth. To remediate the debris environment in LEO, active debris removal must be considered. This presentation will provide an updated assessment of the debris environment after the Iridium 33/Cosmos 2251 collision, an analysis of several future environment projections based on different scenarios, and a projection of collision activities in LEO in the near future. The need to use active debris removal to stabilize future debris environment will be demonstrated and the effectiveness of various active debris removal strategies will be quantified.

  13. A Wide-Field View of Leo II -- A Structural Analysis Using the SDSS

    CERN Document Server

    Coleman, Matthew G; Rix, Hans-Walter; Grebel, Eva K; Koch, Andreas

    2007-01-01

    Using SDSS I data, we have analysed the stellar distribution of the Leo II dwarf spheroidal galaxy (distance of 233 kpc) to search for evidence of tidal deformation. The existing SDSS photometric catalogue contains gaps in regions of high stellar crowding, hence we filled the area at the centre of Leo II using the DAOPHOT algorithm applied to the SDSS images. The combined DAOPHOT-SDSS dataset contains three-filter photometry over a 4x4 square degree region centred on Leo II. By defining a mask in three-filter colour-magnitude space, we removed the majority of foreground field stars. We have measured the following Leo II structural parameters: a core radius of r_c = 2.64 +/- 0.19 arcmin (178 +/- 13 pc), a tidal radius of r_t = 9.33 +/- 0.47 arcmin (632 +/- 32 pc) and a total V-band luminosity of L_V = (7.4 +/- 2.0) times 10^5 L_sun (M_V = -9.9 +/- 0.3). Our comprehensive analysis of the Leo II structure did not reveal any significant signs of tidal distortion. The internal structure of this object contains onl...

  14. The Oxygen and Nitrogen Abundance of Leo A and GR 8

    Science.gov (United States)

    van Zee, L.; Skillman, E. D.; Haynes, M. P.

    1999-05-01

    Gas phase abundances are one of the best measures of the intrinsic metallicity of low mass galaxies. We recently obtained low resolution long slit optical spectra of several HII regions in Leo A and GR 8 with the Palomar 5m telescope. Previous studies of the resolved stellar population of Leo A indicated that the stars have metallicities approximately 2% of solar (Tolstoy et al. 1998). Preliminary analysis of the HII region spectra, and that of a planetary nebula, indicates that the gas phase oxygen abundance of Leo A is approximately 3% of solar. This confirms the result of Skillman et al. (1989), who also derived an oxygen abundance for Leo A from a planetary nebula. Similarly, for GR 8 we find a mean oxygen abundance of 5% of solar. For all the HII regions, the derived log(N/O) is -1.5 +/- 0.1, as has been found for other low metallicity systems. These new observations of multiple HII regions in Leo A and GR 8 confirm that metals in low mass galaxies are well mixed.

  15. Variable Stars in Leo A RR Lyraes, Short-period Cepheids, and Implications on Stellar Content

    CERN Document Server

    Dolphin, A E; Claver, J; Skillman, E D; Cole, A A; Gallagher, J S; Tolstoy, E; Dohm-Palmer, R C; Mateo, M

    2002-01-01

    We present the results of a search for short-period variable stars in Leo A. We have found 92 candidate variables, including eight candidate RR Lyrae stars. From the RR Lyraes, we measure a distance modulus of (m-M)_0 = 24.51 +/- 0.12, or 0.80 +/- 0.04 Mpc. This discovery of RR Lyraes confirms, for the first time, the presence of an ancient (> ~11 Gyr) population in Leo A accounting for at least 0.1% of the galaxy's V luminosity. We have also discovered a halo of old (> ~2 Gyr) stars surrounding Leo A, with a scale length roughly 50% larger than that of the dominant young population. We also report the discovery of a large population of Cepheids in Leo A. The median absolute magnitude of our Cepheid sample is M_V = -1.1, fainter than 96% of SMC and 99% of LMC Cepheids. Their periods are also unusual, with three Cepheids that are deduced to be pulsating in the fundamental mode having periods of under 1 day. Upon examination, these characteristics of the Leo A Cepheid population appear to be a natural extension...

  16. Approach to Improving TT&C Coverage Rate of LEO and MEO Spacecrafts in China

    Institute of Scientific and Technical Information of China (English)

    YangYongan; ZhangFengxiang; FengZhuren; ZhaoYudong

    2004-01-01

    With the rapid increase of number and types of Low Earth Orbit (LEO) and Medium Earth Orbit (MEO) spacecrafts in China,the insufficiency of TT&C resources is exposed. How to improve LEO and MEO TT&C coverage rate has become the key problem of TT&C system,which should be resolved urgently. Firstly, the basic concepts of TT&C coverage are discussed and the relation between TT&C coverage of ground station and geography latitude of ground station as well as spacecraft altitude are analyzed. Secondly, the United States NASA TT&C network is taken as an instance to describe the developing process of TT&C network. Finally, in combination with TT&C activities of LEO and MEO spacecrafts in China, the method to heighten TT&C coverage rate is put forward, such as rational establishing station, space resources application ,international TT&C cooperation etc.

  17. ALFALFA in the Leo Region: Looking for Missing Satellites in HI

    CERN Document Server

    Stierwalt, Sabrina

    2007-01-01

    The location of two nearby galaxy groups within ~20 Mpc in the Leo region allows for a detailed study of low-mass galaxies. A catalog of HI line detections in Leo (9h36m < RA <11h36m, +8deg < dec < +16deg) has been made from the blind HI survey ALFALFA. More sensitive single-pixel Arecibo observations targeted Leo dwarf candidates noted optically by Karachentsev et al 2004 (K04) to determine group members and allow for a comparison of HI and optically-selected samples. This presentation highlights the differences between the two samples and the significant contribution blind HI surveys can make to the missing satellites problem.

  18. New dynamic routing algorithm based on MANET in LEO/MEO satellite network

    Institute of Scientific and Technical Information of China (English)

    LI Zhe; LI Dong-ni; WANG Guang-xing

    2006-01-01

    The features of low earth orbit/medium earth orbit (LEO/MEO) satellite networks routing algorithm based on inter-satellite link are analyzed and the similarities between satellite networks and mobile Ad Hoc network (MANET) are pointed out.The similar parts in MANET routing protocol are used in the satellite network for reference.A new dynamic routing algorithm based on MANET in LEO/MEO satellite networks,which fits for the LEO/MEO satellite communication system,is proposed.At the same time,the model of the algorithm is simulated and features are analyzed.It is shown that the algorithm has strong adaptability.It can give the network high autonomy,perfect function,low system overhead and great compatibility.

  19. A Multicast Routing Algorithm for Datagram Service in Delta LEO Satellite Constellation Networks

    Directory of Open Access Journals (Sweden)

    Yanpeng Ma

    2014-04-01

    Full Text Available Satellites can broadcast datagram over wide areas, therefore, the satellite network has congenital advantages to implement multicast service. LEO satellite has the property of efficient bandwidth usage, lower propagation delay and lower power consumption in the user terminals and satellites. Therefore, the constellation network composed by LEO satellites is an essential part of future satellite communication networks. In this paper, we propose a virtual center based multicast (VCMulticast routing algorithm for LEO satellite constellation network. The algorithm uses the geographic center information of group users to route multicast datagrams, with less memory, computer power and signaling overhead. We evaluate the delay and performance of our algorithm by means of simulations in the OPENET simulator. The results indicate that the delay of the proposed multicast method exceeds the minimum propagation by at most 29.1% on the average, which is a quite acceptable achievement, considering the resource overhead reduction that can be introduced by our proposal

  20. Dynamical evidence for a strong tidal interaction between the Milky Way and its satellite, Leo V

    Science.gov (United States)

    Collins, Michelle L. M.; Tollerud, Erik J.; Sand, David J.; Bonaca, Ana; Willman, Beth; Strader, Jay

    2017-01-01

    We present a chemodynamical analysis of the Leo V dwarf galaxy, based on Keck II DEIMOS spectra of 8 member stars. We find a systemic velocity for the system of population through extended star formation. Owing to the tentative photometric evidence for tidal substructure around Leo V, we also investigate whether there is any evidence for tidal stripping or shocking of the system within its dynamics. We measure a significant velocity gradient across the system, of dv/dχ = -4.1^{+2.8}_{-2.6} km s^{-1} per arcmin (or dv/dχ = -71.9^{+50.8}_{-45.6} km s^{-1} kpc-1), which points almost directly toward the Galactic centre. We argue that Leo V is likely a dwarf on the brink of dissolution, having just barely survived a past encounter with the centre of the Milky Way.

  1. Handover aspects for a Low Earth Orbit (LEO) CDMA Land Mobile Satellite (LMS) system

    Science.gov (United States)

    Carter, P.; Beach, M. A.

    1993-01-01

    This paper addresses the problem of handoff in a land mobile satellite (LMS) system between adjacent satellites in a low earth orbit (LEO) constellation. In particular, emphasis is placed on the application of soft handoff in a direct sequence code division multiple access (DS-CDMA) LMS system. Soft handoff is explained in terms of terrestrial macroscopic diversity, in which signals transmitted via several independent fading paths are combined to enhance the link quality. This concept is then reconsidered in the context of a LEO LMS system. A two-state Markov channel model is used to simulate the effects of shadowing on the communications path from the mobile to each satellite during handoff. The results of the channel simulation form a platform for discussion regarding soft handoff, highlighting the potential merits of the scheme when applied in a LEO LMS environment.

  2. GEO vs. LEO Space Telecommunication Systems Commercial Set Up, Finance &Economics

    Science.gov (United States)

    Kreisel, Joerg

    2002-01-01

    Space-based commercial telecommunication systems - especially in GEO - still represent the big volume segment in commercial space and probably will do so for a while. Although such end-to-end systems both in GEO and LEO are using satellites, ground stations, and service centers, etc., their commercial genesis differs significantly. Based on existing and planned space telecommunication businesses, this paper deals with prime characteristics of commercial GEO and LEO systems and their differences. In a tutorial way the stages of development of both LEO- and GEO-type business ventures are presented. The entire commercial development path is covered (concept, business plan, financing, partnership, growth, etc.). Focus is to understand what drives space telecommunication business and what it takes to start such new commercial space ventures. The perspective given is also based on the author's longstanding background in space commercialization and experiences made as a venture capitalist.

  3. Atividade antifúngica, in vitro, do óleo de café verde

    OpenAIRE

    Elizei,Virgínia Guerra; CHALFOUN, Sara Maria; Botelho,Deila Magna dos Santos; Rebelles,Pedro Paulo Reis

    2016-01-01

    RESUMO: O objetivo deste trabalho foi avaliar o efeito do contato direto e da fração volátildo óleo de café verde, testado nas concentrações de 500, 1.000, 1.500 e 2.000 µL L-1, sobre o crescimento micelial e a esporulação dos fungos Penicillium roqueforti e Rhizopus stolonifer. O óleo essencial de cravo-da-índia na concentração de 800 µL L-1 foi utilizado para comparação. Nas concentrações de 1.500 e 2.000 µL L-1, o óleo de café verde em contato direto proporcionou redução da esporulação do ...

  4. Efecto de los aditivos oxigenados en las propiedades de los gasóleos de automoción

    OpenAIRE

    España Gutiérrez, Sandra

    2015-01-01

    Los aditivos oxigenados modifican las propiedades de los gasóleos de automoción. En este Trabajo Fin de Máster se analizan las propiedades de algunos de los aditivos sobre los gasóleo de automoción y se estudia experimentalmente las propiedades del butanol como aditivo

  5. A novel data association scheme for LEO space debris surveillance based on a double fence radar system

    Science.gov (United States)

    Huang, Jian; Hu, Weidong; Xin, Qin; Guo, Weiwei

    2012-12-01

    The increasing amount of space debris threatens to seriously deteriorate and damage space-based instruments in Low Earth Orbit (LEO) environments. Therefore, LEO space debris surveillance systems must be developed to provide situational awareness in space and issue warnings of collisions with LEO space debris. In this paper, a double fence radar system is proposed as an emerging paradigm for LEO space debris surveillance. This system exhibits several unique and promising characteristics compared with existing surveillance systems. In this paper, we also investigate the data association scheme for LEO space debris surveillance based on a double fence radar system. We also perform a theoretical analysis of the performance of our proposed scheme. The superiority and the effectiveness of our novel data association scheme is demonstrated by experimental results. The data used in our experiments is the LEO space debris catalog produced by the North American Air Defense Command (NORAD) up to 2009, especially for scenarios with high densities of LEO space debris, which were primarily produced by the collisions between Iridium 33 and Cosmos 2251. We hope that our work will stimulate and benefit future work on LEO space debris surveillance approaches and enable construction of the double fence radar system.

  6. El íleo biliar: una revisión de la literatura médica

    Directory of Open Access Journals (Sweden)

    C.F. Ploneda-Valencia

    2017-07-01

    Conclusiones: El objetivo del tratamiento del íleo biliar es liberar la obstrucción, obtenido a través de la enterolitotomía. Esta es la técnica recomendada para el manejo del íleo biliar debido a su morbimortalidad menor, comparada con las otras técnicas.

  7. Óleos essenciais de manjericão e capim citronela no controle de larvas de Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Ronice Alves Veloso

    2015-07-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito larvicida do óleo essencial do manjericão (Ocimum basilicum L.e do capim citronela (Cymbopogon nardus L. em larvas de Aedes aegypti. Os tratamentos utilizados para cada tipo de óleo foram: água destilada; água destilada + dimetilsulfóxido (DMSO; 2,5µL do óleo essencial; 5,0µL do óleo essencial; 7,5µL do óleo essencial; e 10,0µL do óleo essencial. As avaliações consistiram de contagem do número de larvas mortas em oito épocas (intervalos regulares de três horas. Os óleos essenciais de manjericão e do capim citronela apresentaram eficiente ação larvicida, causando a morte das larvas de A. aegypti em última fase larval. As alíquotas de 5,0, 7,5 e 10,0 µL do óleo essencial do capim citronela foram mais eficientes apresentando a partir da segunda época de avaliação 100% de larvas mortas.

  8. Kulturmorphologie und Neopaganismus. Der Glaube des Leo Frobenius - Kulturmorphologie and Neopaganism. The beliefs of des Leo Frobenius

    Directory of Open Access Journals (Sweden)

    Bernhard Streck

    2015-11-01

    Full Text Available Anthropologists are used to describing the religions of others, nut not their own beliefs. In the human sciences we rarely find information about the religious beliefs of researchers. But carefully examining published and unpublished writings, we can still find some indications regarding the authors’ values, which they may not have always intended to disclose to the public. This is in spite of the fact or perhaps, more correctly, because they are closely related to the theory and practice of their science. To illustrate this rather apocryphal relationship between an author’s basic convictions and his published opinions, in this essay we take the example of Leo Frobenius (1873-1938, a researcher who remained on the fringes of the academic world. As an autodidact ethnologist he was already very enthusiastic about the mythologies of the world at a very young age, but instead of a “global myth” he published a catalogue of mythological themes or “mythologems”, which he considered as universal (Die Weltanschauung der Naturvölker – “the worldview of primitive peoples”, 1898; Das Zeitalter des Sonnengottes – “In the era of the Sun God”, 1904. Unlike the mythologies written much later (1964-1971 by Claude Lévi-Strauss (1908-2009, they do not deal with formal structures of thought, but rather with an archaic cosmology similar to the archetypes we find in the later works of Carl Gustav Jung (1875-1961 or Mircea Eliade (1907-1986. In search of these archetypal images of cosmic evolution, Frobenius collected folk tales and later rock paintings, which he copied by hand during his field research (12 expeditions to Africa between 1904 and 1935. The birth in death, the ritual murder of the Holy King or High Priest, the complementarity of the sexes (for example the numbers 3 and 4 in the sum 7, the law that a culture's rise must inevitably be followed by its decline – these all are ideas that have determined the work of this researcher

  9. Dynamical evidence for a strong tidal interaction between the Milky Way and its satellite, Leo V

    Science.gov (United States)

    Collins, Michelle L. M.; Tollerud, Erik J.; Sand, David J.; Bonaca, Ana; Willman, Beth; Strader, Jay

    2017-05-01

    We present a chemodynamical analysis of the Leo V dwarf galaxy, based on the Keck II DEIMOS spectra of eight member stars. We find a systemic velocity for the system of < v_r\\rangle = 170.9^{+ 2.1}_{-1.9} km s^{-1} and barely resolve a velocity dispersion for the system, with σ _{vr} = 2.3^{+3.2}_{-1.6} km s^{-1}, consistent with previous studies of Leo V. The poorly resolved dispersion means we are unable to adequately constrain the dark-matter content of Leo V. We find an average metallicity for the dwarf of [Fe/H] =-2.48 ± 0.21 and measure a significant spread in the iron abundance of its member stars, with -3.1 ≤ [Fe/H] ≤-1.9 dex, which clearly identifies Leo V as a dwarf galaxy that has been able to self-enrich its stellar population through extended star formation. Owing to the tentative photometric evidence for the tidal substructure around Leo V, we also investigate whether there is any evidence for tidal stripping or shocking of the system within its dynamics. We measure a significant velocity gradient across the system, of dv/dχ = -4.1^{+2.8}_{-2.6} km s^{-1} arcmin-1 (or dv/dχ = -71.9^{+50.8}_{-45.6} km s^{-1} kpc-1), which points almost directly towards the Galactic Centre. We argue that Leo V is likely a dwarf on the brink of dissolution, having just barely survived a past encounter with the centre of the Milky Way.

  10. Potencial inseticida de óleos de origem vegetal sobre Grapholita molesta (Busck (Lepidoptera: Tortricidae

    Directory of Open Access Journals (Sweden)

    J.F. Colpo

    2014-06-01

    Full Text Available Em decorrência do estudo das interações químicas entre insetos e herbívoros, e do avanço da pesquisa fitoquímica, é conhecida ampla variedade de produtos naturais com potencial inseticida. Grapholita molesta (Busck (Lepidoptera: Tortricidae, mariposa-oriental, é uma das principais pragas do pessegueiro, danificando brotações e frutos. O objetivo do presente estudo foi verificar a mortalidade, atratividade e deterrência de óleos vegetais em G. molesta. Ovos e pupas de insetos provindos de criação artificial foram imersos nos óleos essenciais de Elionurus muticus (Spreng. Kuntze e Cymbopogon winterianus Jowitt ex Bor nas concentrações de 0,25%, 0,5%, 1% e 0,5%, 1%, 5%. Os testes de atratividade foram realizados em olfatômetro do tipo "Y". A deterrência à oviposição foi testada em gaiolas sem escolha e de dupla escolha. O óleo de E. muticus aplicado em ovos de G. molesta nas três concentrações causou mortalidades maiores que 30%, diferindo significativamente dos controles (p<0,05. A mortalidade causada pelo óleo de citronela foi em torno de 70%, significativamente superior ao controle (p<0,01. O óleo de citronela aplicado a 1% em pupas causou mortalidade de 99,8%. No teste com o olfatômetro, não houve atratividade dos adultos para nenhum dos óleos. A média de ovos no substrato com o tratamento (0,33±0,33, foi significativamente menor que no controle (7,3±0,88 (p<0,01, indicando deterrência à oviposição.

  11. Geocenter Coordinates from a Combined Processing of LEO and Ground-based GPS Observations

    Science.gov (United States)

    Männel, Benjamin; Rothacher, Markus

    2017-04-01

    The GPS observations provided by the global IGS (International GNSS Service) tracking network play an important role for the realization of a unique terrestrial reference frame that is accurate enough to allow the monitoring of the Earth's system. Combining these ground-based data with GPS observations tracked by high-quality dual-frequency receivers on-board Low Earth Orbiters (LEO) might help to further improve the realization of the terrestrial reference frame and the estimation of the geocenter coordinates, GPS satellite orbits and Earth rotation parameters (ERP). To assess the scope of improvement, we processed a network of 50 globally distributed and stable IGS-stations together with four LEOs (GRACE-A, GRACE-B, OSTM/Jason-2 and GOCE) over a time interval of three years (2010-2012). To ensure fully consistent solutions the zero-difference phase observations of the ground stations and LEOs were processed in a common least-square adjustment, estimating GPS orbits, LEO orbits, station coordinates, ERPs, site-specific tropospheric delays, satellite and receiver clocks and ambiguities. We present the significant impact of the individual LEOs and a combination of all four LEOs on geocenter coordinates derived by using a translational approach (also called network shift approach). In addition, we present geocenter coordinates derived from the same set of GPS observations by using a unified approach. This approach combines the translational and the degree-one approach by estimating translations and surface deformations simultaneously. Based on comparisons against each other and against geocenter time series derived by other techniques the effect of the selected approach is assessed.

  12. Óleos essenciais e vegetais no controle in vitro de Colletotrichum gloeosporioides

    Directory of Open Access Journals (Sweden)

    K. RAMOS

    Full Text Available RESUMO O objetivo deste trabalho foi avaliar a atividade antifúngica de óleos essenciais e vegetais no controle in vitro de Colletotrichum gloeosporioides, agente causal da antracnose em pós-colheita de frutíferas. Treze óleos essenciais foram utilizados em concentrações de 0,00%, 0,40%, 0,80%, 1,70%, 3,20%, 6,25%, 12,50%, 25,00%, 50,00% e 100,00%, e uma linhagem padrão de Colletotrichum gloeosporioides. Foram avaliadas a concentração inibitória mínima e a concentração mínima fungicida a fim de caracterizar o potencial de cada um dos óleos essenciais avaliados. Verificou-se que os óleos utilizados apresentaram atividade fungicida em diferentes concentrações, as quais variaram de 0,80% (melaleuca, 3,20%, (eucalipto, 6,25% (limão, capim limão, cravo da índia, canela e nim, 12,5% (hortelã e citronela, 25% (copaíba, 50% (coco e gengibre e 100% (manjericão. O óleo de nim apresentou maior redução da carga microbiana em função do tempo de exposição, sendo necessários 30 minutos para anulação da contagem microbiana. O efeito antifúngico dos óleos essenciais, para controle de Colletotrichum gloeosporioides, depende da planta e da concentração empregada.

  13. All-digital Carrier Frequency Tracking Method in LEO DS/SS Communication

    Institute of Scientific and Technical Information of China (English)

    XING Ke-fei; YANG Jun; ZHANG Chuan-sheng; WANG Yue-ke

    2006-01-01

    An efficient method to track the carrier frequency which is recommended to use in low earth orbit(LEO) direct-sequence spread-spectrum(DS/SS) communication system is given. The carrier frequency drifts quicker in LEO DS/SS communication system, its tracking problem becomes much more important especially in digital receiver with the limits of physical shape and power. Under the condition of coarse carrier frequency synchronization, a digital tracking method based on least square method(LSM) is proved to be a quick, simple and efficient method. Numerical results and charts are given.

  14. Key issues of multiple access technique for LEO satellite communication systems

    Institute of Scientific and Technical Information of China (English)

    温萍萍; 顾学迈

    2004-01-01

    The large carrier frequency shift caused by the high-speed movement of satellite (Doppler effects) and the propagation delay on the up-down link are very critical issues in an LEO satellite communication system, which affects both the selection and the implementation of a suitable access method. A Doppler based multiple access technique is used here to control the flow and an MPRMA-HS protocol is proposed for the application in LEO satellite communication systems. The extended simulation trials prove that the proposed scheme seems to be a very promising access method.

  15. A DISTRIBUTED QOS ROUTING BASED ON ANT ALGORITHM FOR LEO SATELLITE NETWORK

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Low Earth Orbit (LEO) satellites provide short round-trip delays and are becoming increasingly important. One of the challenges in LEO satellite networks is the development of specialized and efficient routing algorithms. To satisfy the QoS requirements of multimedia applications, satellite routing protocols should consider handovers and minimize their effect on the active connections. A distributed QoS routing scheme based on heuristic ant algorithm is proposed for satisfying delay bound and avoiding link congestion. Simulation results show that the call blocking probabilities of this algorithm are less than that of Shortest Path First (SPF) with different delay bound.

  16. An Assessment of the January 2007 Chinese ASAT Test on the LEO Environment

    Science.gov (United States)

    Talent, D.

    Over the past several decades there has been increasing concern regarding the growth of the orbital debris population in the Low Earth Orbit (LEO) environment. Even under the best of circumstances the debris population may be expected to increase under conditions of ambient use by the space-faring nations of the world. It is easy to see that such a situation will obtain since the operational lifetimes of most on-orbit systems are typically less than a decade, while their orbital lifetimes may be many decades to hundreds of years or more. Historically, very little has been done regarding the removal of defunct orbital systems. Making matters worse, there have been many cases of spontaneous explosion of derelict upper stages on orbit. In such an event, a single large "hazard to navigation" becomes hundreds to thousands of pieces of orbiting shrapnel. As the numbers of debris objects increases, for whatever reason, so does the threat of collision with high-value operational assets. Thus, given the importance of minimizing orbital debris in LEO, it is obvious that any nation conducting anti-satellite (ASAT) tests should do so in a responsible fashion - minimizing the long-term deposition of large numbers of orbital debris objects at operational LEO altitudes. It is the thesis of this paper that the January 2007 ASAT test conducted by the Chinese government was particularly careless in this regard. In support of this statement, Oceanit's LEO environment model, PODEM (patented in 2004), was employed. The Chinese ASAT test was conducted successfully at an altitude of about 850 km producing large numbers of debris objects. Results, based on an approximation to this recent event, utilizing the PODEM model, suggest that meter-size debris pieces may remain in the LEO environment for hundreds of years. By contrast, debris ranging in size from one to several centimeters may be expected to drift down, due to drag, through lower LEO altitudes producing a transient spike in hazard

  17. Ileostomia continente com preservação da papila íleo-cecal

    OpenAIRE

    FORMIGA GJS

    2000-01-01

    Seis doentes foram submetidos a ileostomia continente com preservação da papila íleo-cecal, como tempo cirúrgico complementar à proctocolectomia e à colectomia totais, para tratamento de doença inflamatória intestinal e polipose adenomatosa familiar, associada a pólipo degenerado no reto inferior. A técnica utilizada de ileostomia continente preserva a papila íleo-cecal e uma pequena borda circular de parede cecal exteriorizados na parede abdominal. O débito ileal, na primeira semana pós-oper...

  18. Integrated Ideas of a Life Warrior ~ An Interview with Leo Fong

    Directory of Open Access Journals (Sweden)

    Peter Hobart

    2012-07-01

    Full Text Available Mr. Leo Fong is the architect and founder of a system of martial arts known as Wei Kuen Do (man. Hui Quan Dao—the Way of the Integrated Fist. Leo Fong trained in a variety of Chinese disciplines, including Shaolin, Choy Lay Fut and Tiger Claw, and was a close associate of Bruce Lee. Over the course of his studies, Master Fong combined many of the aspects of Chinese martial arts with principles of western boxing, to produce his own, unique and devastating system of self-defense.

  19. Potencial de óleos essenciais de plantas medicinais no controle de fitopatógenos

    Directory of Open Access Journals (Sweden)

    M.C.M. FONSECA

    2015-03-01

    Full Text Available Além do valor como recurso terapêutico, plantas medicinais também possuem potencial para serem utilizadas como fonte de princípios ativos contra fitopatógenos. O objetivo deste trabalho foi avaliar o efeito de óleos essenciais das espécies medicinais Baccharis dracunculifolia (alecrim-do-campo, Schinus terebinthifolius (aroeirinha e Porophyllum ruderale (arnica-brasileira sobre o crescimento dos fungos fitopatogênicos Fusarium oxysporum f. sp. phaseoli (Fop, F. solani f. sp. phaseoli (Fsp, Sclerotinia sclerotiorum (Ss, S. minor (Sm, Rhizoctonia solani (Rs, Sclerotium rolfsii (Sr e Macrophomina phaseolina (Mp. Avaliou-se em placas de Petri o crescimento radial desses fungos em meio batata-dextrose-ágar (BDA com cinco concentrações (0, 250, 500, 1000 e 3000 mg L-1 dos óleos essenciais. Discos de micélio (5 mm de diâmetro de cada fungo em crescimento foram transferidos para placas de Petri que foram mantidas a 23°C no escuro por 48 horas. O óleo essencial de alecrim-do-campo foi o mais eficiente na redução do crescimento micelial de todos os fungos, com inibição completa quando se utilizou a concentração de 3000 mg L-1. A redução de crescimento variou de 29% (Fs a 80% (Rs a 250 mg L-1 do óleo essencial de alecrim-do-campo; a 500 mg L-1, variou de 29% (Fs a 98% (Sr; e a 1000 mg L-1, de 41% (Fs a 100% (Sr. A redução do crescimento dos fungos pelo óleo de aroeirinha na concentração de 3000 mg L-1 variou de 27% (Fsp a 74% (Rs. Nessa concentração, o óleo de arnica-brasileira reduziu o crecimento micelial de Ss em 72%, o de Rs em 80% e o de Mp em 82%, sem efeitos significativos sobre o crescimento micelial de Fsp e Fop. Conclui-se que os óleos essenciais de alecrim-do-campo, aroeirinha e arnica-brasileira possuem potencial para o controle dos fungos fitopatogênicos estudados, com destaque para o óleo de alecrim-do-campo.

  20. Refinação de óleos vegetais e fracionamento contínuo de óleo de Palma

    OpenAIRE

    Mota, Daniel Santos

    2016-01-01

    Este relatório enquadra-se na unidade de formação de estágio profissionalizante, do Mestrado em Engenharia Alimentar da Escola Superior Agrária de Coimbra e traduz algumas partes do trabalho realizado ao longo de 6 meses de estágio, na empresa Rogério Leal. O estágio consistiu na observação, e posterior participação, dos métodos de refinação, hidrogenação, interestereficação e fracionamento do óleo de palma. Neste relatório descreve-se o método de refinação físico e hidrogenação do óleo...

  1. Estruturação de óleo de palma e emulsões utilizando óleo de palma totalmente hidrogenado e lecitina de soja

    OpenAIRE

    Valéria da Silva Santos

    2014-01-01

    Resumo: O óleo de palma (PO) destaca-se por ser uma matéria-prima com grande potencial de aplicação em diversos produtos. Porém, quando aplicado de maneira isolada, apresenta cristalização lenta, gerando problemas para a indústria de alimentos. A fim de acelerar a cristalização utilizam-se compostos que podem, além de contribuir para a redução do período de indução, atuar como agentes estruturantes, atual foco em desenvolvimento na área de óleos e gorduras. Este estudo tem por objetivos avali...

  2. Research on routing technology of a LEO&MEO double layer satellite network%LEO&MEO双层卫星网络路由技术研究

    Institute of Scientific and Technical Information of China (English)

    罗有平

    2006-01-01

    首先分别分析了GEO层、MEO层、LEO层卫星的优缺点,接着简述了LEO&MEO双层卫星网络的特点及对路由算法的要求,然后对已有的卫星网络路由算法进行简要分析,最后提出了一套适合LEO&MEO双层卫星网络的动态路由技术.在拓扑快照DT-DVTR路由算法和MLSR的基础上,设计了动态路由算法,该路由算法采用了主动路由和按需路由相结合的方式,使得路由查找时间短、效率高.

  3. Refinação de óleos vegetais e fracionamento contínuo de óleo de Palma

    OpenAIRE

    Mota, Daniel Santos

    2016-01-01

    Este relatório enquadra-se na unidade de formação de estágio profissionalizante, do Mestrado em Engenharia Alimentar da Escola Superior Agrária de Coimbra e traduz algumas partes do trabalho realizado ao longo de 6 meses de estágio, na empresa Rogério Leal. O estágio consistiu na observação, e posterior participação, dos métodos de refinação, hidrogenação, interestereficação e fracionamento do óleo de palma. Neste relatório descreve-se o método de refinação físico e hidrogenação do óleo...

  4. Ever Ready to Go: The Multiple Exiles of Leo Szilard

    Science.gov (United States)

    Frank, Tibor

    2005-06-01

    I argue that to understand the life and work of Leo Szilard (1898 1964) we have to understand, first, that he was driven by events to numerous departures, escapes, and exiles, changing his religion, his language, his country of residence, and his scientific disciplines; second, that he was a man haunted by major moral dilemmas throughout his life, burdened by a sincere and grave sense of responsibility for the fate of the world; and third, that he experienced a terrible sense of déjà vu: his excessive sensitivity and constant alertness were products of his experiences as a young student in Budapest in 1919. The mature Szilard in Berlin of 1933, and forever after, was always ready to move. I proceed as follows:After a brief introduction to his family background, youth, and education in Budapest, I discuss the impact of his army service in the Great War and of the tumultous events in Hungary in 1918 1919 on his life and psyche, forcing him to leave Budapest for Berlin in late 1919. He completed his doctoral degree under Max von Laue (1879 1960) at the University of Berlin in 1922 and his Habilitationsschrift in 1925. During the 1920s and early 1930s, he filed a number of patents, several of them jointly with Albert Einstein (1879 1955). He left Berlin in March 1933 for London where he played a leading role in the rescue operations for refugee scientists and scholars from Nazi Germany. He also carried out notable research in nuclear physics in London and Oxford before immigrating to the United States at the end of 1938. He drafted Einstein’s famous letter of August 2, 1939, to President Franklin D. Roosevelt, worked in the Manhattan Project during World War II, initiated a petition to President Harry S. Truman not to use the bomb on Japan, and immediately after the war was a leader in the scientists’ movement that resulted in civilian control of nuclear energy. In 1946 he turned to biology, in which his most significant contribution was to formulate a theory of

  5. LEO/MEO双层卫星网络设计及仿真%Design and Simulation on a LEO/MEO Double-Layered Satellite Network

    Institute of Scientific and Technical Information of China (English)

    张基伟; 梁俊; 肖楠; 田斌

    2011-01-01

    Aiming at the issue of simplex function and low reliability in monolayer satellite network and high ISL complexity in three-layered satellite network, a framework of LEO/MEO network is proposed. Based on the "worst observational point" and " street of coverage" theory, a discontinuous connection LFO/MEO constellation is designed, and the principle to establish ISL is put forward. Furthermore , experimental results show that the network has the ability of global coverage and is easy to establish ISL.%针对单层卫星网络功能单一、可靠性较低以及三重卫星网络链路冗余度过高、实现复杂的问题,提出了利用LEO/MEO卫星构建双层网络的构想.基于"最坏观察点"与"覆盖带"理论设计了"弱连接"的LEO/MEO双层卫星网络星座,给出了星际链路建立原则.仿真结果表明,所设计的卫星网络具有全天时全球覆盖能力,有利于星际链路的建立.

  6. CALIDAD MICROBIOLÓGICA DE PROPÓLEO CRUDO Y SÓLIDOS SOLUBLES DE EXTRACTOS DE PROPÓLEOS DE Apis mellifera EN COLOMBIA

    Directory of Open Access Journals (Sweden)

    C. Talero

    2012-01-01

    Full Text Available Se tomaron cincuenta y nueve muestras de propóleo crudo recolectadas en tres orígenes geográficos de Colombia, a las cuales se les realizó control de la calidad microbiológica, y se determinó el porcentaje de extracto seco obtenido de las extracciones etanólicas de propóleo ( ee P al 70 y 96%. s e cuantificaron los grupos indicadores mesófilos aerobios, coliformes totales, coliformes fecales, Staphylococcus sp., mohos y levaduras, y se encontraron conteos en promedio de 93x10 3 ; 79x10 2 ; <1; 94; 10x10 4 UFC/g, res - pectivamente. La detección de patógenos se realizó para Escherichia coli y Staphylococcus aureus , los cuales estuvieron presentes en el 4 y 2% de las muestras, respectivamente. Los hallazgos microbiológicos se compararon con normas de calidad de Japón, Perú y e l s alvador; se encontró que el grupo indicador mohos y levaduras fue el más crítico, donde 92 a 94% de las muestras evaluadas estuvieron por fuera de los límites exigidos por estas normas. Los resultados indican que las extracciones con etanol al 70 y 96% de propóleos colombianos, en promedio obtuvieron 93,0 y 175,3 mg/ml de extracto seco, respectivamente. La concentración de extracto seco se comparó con la normatividad existente en Brasil, a rgentina y Japón. Para la norma más exigente, que corresponde a la brasileña, se hallaron porcentajes de cumplimiento del 53,4 y 56,1% para ee P 70 y 96%, respectivamente, y para la norma de Japón se encontraron aceptables 75,9 y 69,7% de los ee P 70 y 96%, respectivamente. Los resultados están asociados al origen fitogeo - gráfico y a la producción no especializada de propóleos. e n este estudio se incluyeron muestras de propóleo crudo de países como Bélgica, Chile, Cuba y Nueva Zelanda.

  7. Leo Burnett wins agency of the year title in Estonia and Lithuania

    Index Scriptorium Estoniae

    2004-01-01

    Eesti Kuldmuna reklaamikonkursil, Leedu reklaamifestivalil Adrenalinas aasta reklaamiagentuuri tiitli pälvinud ettevõttest Kontuur Leo Burnett. Madis Laas, Tomas Ramanauskas ja Marius Petrukaitis vastavad küsimustele firma edu võimalike põhjuste ja tulevikuplaanide kohta

  8. The ACS LCID Project - VIII. The short-period Cepheids of Leo A

    NARCIS (Netherlands)

    Bernard, Edouard J.; Monelli, Matteo; Gallart, Carme; Fiorentino, Giuliana; Cassisi, Santi; Aparicio, Antonio; Cole, Andrew A.; Drozdovsky, Igor; Hidalgo, Sebastian L.; Skillman, Evan D.; Stetson, Peter B.; Tolstoy, Eline

    2013-01-01

    We present the results of a new search for variable stars in the Local Group dwarf galaxy Leo A, based on deep photometry from the Advanced Camera for Surveys onboard the Hubble Space Telescope. We detected 166 bona fide variables in our field, of which about 60 per cent are new discoveries and 33 c

  9. The ACS LCID Project : VIII. The short-period Cepheids of Leo A

    NARCIS (Netherlands)

    Bernard, Edouard J.; Monelli, Matteo; Gallart, Carme; Fiorentino, Giuliana; Cassisi, Santi; Aparicio, Antonio; Cole, Andrew A.; Drozdovsky, Igor; Hidalgo, Sebastian L.; Skillman, Evan D.; Stetson, Peter B.; Tolstoy, Eline

    2013-01-01

    We present the results of a new search for variable stars in the Local Group dwarf galaxy Leo A, based on deep photometry from the Advanced Camera for Surveys onboard the Hubble Space Telescope. We detected 166 bona fide variables in our field, of which about 60 per cent are new discoveries and 33 c

  10. Research on handover algorithm to reduce the blocking probability in LEO satellite network

    Institute of Scientific and Technical Information of China (English)

    Chen Bingcai; Zhang Naitong; Nie Boxun; Zhou Tingxian

    2006-01-01

    Based on the characteristics of guaranteed handover (GH) algorithm, the finite capacity in one system makes the blocking probability (PB) of GH algorithm increase rapidly in the case of high traffic load. So, when large amounts of multimedia services are transmitted via a single low earth orbit (LEO) satellite system, the PB of it is much higher. In order to solve the problem, a novel handover scheme defined by multi-tier optiral layer selection is proposed. The scheme sufficienfly takes into ac count the characteristics of double-tier satellite network, which is constituted by LEO satellites combined with medium earth orbit (MEO) satellites, and the multimedia transmitted by such network, so it can augment this systematic capacity and effectively reduces the traffic load in the LEO which performs GH algorithm. The detailed processes are also presented. The simulation and numerical results show that the approach integrated with GH algorithm achieves a significant improvement in the PB and practicability, as compared to the single LEO layer network.

  11. The Local Group dwarf leo T : HI on the brink of star formation

    NARCIS (Netherlands)

    Ryan-Weber, Emma V.; Begum, Ayesha; Oosterloo, Tom; Pal, Sabyasachi; Irwin, Michael J.; Belokurov, Vasily; Evans, N. Wyn; Zucker, Daniel B.

    2008-01-01

    We present Giant Meterwave Radio Telescope (GMRT) andWesterbork Synthesis Radio Telescope (WSRT) observations of the recently discovered Local Group dwarf galaxy, Leo T. The peak HI column density is measured to be 7 x 1020 cm(-2), and the total HI mass is 2.8 x 10(5) M-circle dot,, based on a dista

  12. Changes in lion (Panthera leo) home range size in Waza National Park, Cameroon

    NARCIS (Netherlands)

    Tumenta, P.N.; Van't Zelfde, M.; Croes, B.M.; Buij, R.; Funston, P.J.; Haes, de H.A.U.; longh, De H.H.

    2013-01-01

    The spatial ecology of Africa lions (Panthera leo) was studied from 2007 to 2009 in Waza National Park, Cameroon, by equipping individual lions with GPS/VHF radio-collars. Mean home range estimates using 100% minimum convex polygons (MCP) and 95% kernel-density estimation (KDE) were respectively

  13. Tagakiusamine ja kirjutamiskunst / Leo Strauss ; järelsõna Jüri Lipping

    Index Scriptorium Estoniae

    Strauss, Leo, 1899-1973

    2000-01-01

    Ajalooliste tekstide ridade vahele peidetud sõnumi lugemisest. Tsensuuri mõjust filosoofilistele tekstidele. Peidetud sõnumi lugemisest lähtuvast erinevusest eelmoodsate ja uusaegsete filosoofide teostes. Jüri Lipping'u järelsõna Leo Straussi filosoofilistest vaadetest.

  14. Changes in lion (Panthera leo) home range size in Waza National Park, Cameroon

    NARCIS (Netherlands)

    Tumenta, P.N.; Van't Zelfde, M.; Croes, B.M.; Buij, R.; Funston, P.J.; Haes, de H.A.U.; longh, De H.H.

    2013-01-01

    The spatial ecology of Africa lions (Panthera leo) was studied from 2007 to 2009 in Waza National Park, Cameroon, by equipping individual lions with GPS/VHF radio-collars. Mean home range estimates using 100% minimum convex polygons (MCP) and 95% kernel-density estimation (KDE) were respectively 101

  15. Leo P: How Many Metals can a Very Low-Mass, Isolated Galaxy Retain?

    CERN Document Server

    McQuinn, Kristen B W; Dolphin, Andrew; Cannon, John M; Salzer, John J; Rhode, Katherine L; Adams, Elizabeth A K; Berg, Danielle; Giovanelli, Riccardo; Haynes, Martha P

    2015-01-01

    Leo P is a gas-rich dwarf galaxy with an extremely low gas-phase oxygen abundance (3% solar). The isolated nature of Leo P enables a quantitative measurement of metals lost solely due to star formation feedback. We present an inventory of the oxygen atoms in Leo P based on the gas-phase oxygen abundance measurement, the star formation history, and the chemical enrichment evolution derived from resolved stellar populations. The star formation history also provides the total amount of oxygen produced. Overall, Leo P has retained 5 % of its oxygen; 25% of the retained oxygen is in the stars while 75% is in the gas phase. This is considerably lower than the 20-25% calculated for massive galaxies, supporting the trend for less efficient metal retention for lower mass galaxies. The retention fraction is higher than that calculated for other alpha elements (Mg, Si, Ca) in dSph Milky Way satellites of similar stellar mass and metallicity. Accounting only for the oxygen retained in stars, our results are consistent wi...

  16. Atmospheric Models of Flare Stars The Quiescent State of Ad Leo

    CERN Document Server

    Mauas, P

    1994-01-01

    We compute a semi-empirical atmospheric model for the dMe star AD Leo, which constitutes the first model computed to match the continuum observations, as well as a wide set of chromospheric spectral lines. We find good agreement between the computed and observed spectral features, with the exception of the Ca II K line.

  17. An efficient QoS-aware routing algorithm for LEO polar constellations

    Science.gov (United States)

    Tian, Xin; Pham, Khanh; Blasch, Erik; Tian, Zhi; Shen, Dan; Chen, Genshe

    2013-05-01

    In this work, a Quality of Service (QoS)-aware routing (QAR) algorithm is developed for Low-Earth Orbit (LEO) polar constellations. LEO polar orbits are the only type of satellite constellations where inter-plane inter-satellite links (ISLs) are implemented in real world. The QAR algorithm exploits features of the topology of the LEO satellite constellation, which makes it more efficient than general shortest path routing algorithms such as Dijkstra's or extended Bellman-Ford algorithms. Traffic density, priority, and error QoS requirements on communication delays can be easily incorporated into the QAR algorithm through satellite distances. The QAR algorithm also supports efficient load balancing in the satellite network by utilizing the multiple paths from the source satellite to the destination satellite, and effectively lowers the rate of network congestion. The QAR algorithm supports a novel robust routing scheme in LEO polar constellation, which is able to significantly reduce the impact of inter-satellite link (ISL) congestions on QoS in terms of communication delay and jitter.

  18. COMPONENTES MINORITÁRIOS DO ÓLEO DE MAMONA (Ricinus comunnis L.

    Directory of Open Access Journals (Sweden)

    Elina Bastos Caramão

    2007-12-01

    Full Text Available O óleo extraído de sementes de Ricinnus communis L., conhecida como mamona, foi analisado neste trabalho quanto a presença decomponentes minoritários extraídos na fase insaponificável. A extração de insaponificáveis foi realizada conforme o método AOCS(Ca 6a-40 e a análise das amostras de óleo foi realizada por Cromatografia gasosa acoplada a espectrometria de massas (CG-DEMapós derivatização com BSA. Entre as substâncias identificadas encontrou-se o D-tocoferol, g- tocoferol, D5-ergostenol, stigmasterol,obtusifoliol, g-sitosterol, fucosterol e cicloartenol. As amostras de óleo de diferentes variedades de mamona, obtidas por prensagem afrio e por solvente em extrator soxhlet apresentaram diferenças quanto as substâncias separadas. O método empregado para extração eanálise foi apropriado para identificar a presença de componentes minoritários no óleo de mamona.

  19. Leo Burnett wins agency of the year title in Estonia and Lithuania

    Index Scriptorium Estoniae

    2004-01-01

    Eesti Kuldmuna reklaamikonkursil, Leedu reklaamifestivalil Adrenalinas aasta reklaamiagentuuri tiitli pälvinud ettevõttest Kontuur Leo Burnett. Madis Laas, Tomas Ramanauskas ja Marius Petrukaitis vastavad küsimustele firma edu võimalike põhjuste ja tulevikuplaanide kohta

  20. The ACS LCID Project : VIII. The short-period Cepheids of Leo A

    NARCIS (Netherlands)

    Bernard, Edouard J.; Monelli, Matteo; Gallart, Carme; Fiorentino, Giuliana; Cassisi, Santi; Aparicio, Antonio; Cole, Andrew A.; Drozdovsky, Igor; Hidalgo, Sebastian L.; Skillman, Evan D.; Stetson, Peter B.; Tolstoy, Eline

    2013-01-01

    We present the results of a new search for variable stars in the Local Group dwarf galaxy Leo A, based on deep photometry from the Advanced Camera for Surveys onboard the Hubble Space Telescope. We detected 166 bona fide variables in our field, of which about 60 per cent are new discoveries and 33

  1. The ACS LCID Project - VIII. The short-period Cepheids of Leo A

    NARCIS (Netherlands)

    Bernard, Edouard J.; Monelli, Matteo; Gallart, Carme; Fiorentino, Giuliana; Cassisi, Santi; Aparicio, Antonio; Cole, Andrew A.; Drozdovsky, Igor; Hidalgo, Sebastian L.; Skillman, Evan D.; Stetson, Peter B.; Tolstoy, Eline

    We present the results of a new search for variable stars in the Local Group dwarf galaxy Leo A, based on deep photometry from the Advanced Camera for Surveys onboard the Hubble Space Telescope. We detected 166 bona fide variables in our field, of which about 60 per cent are new discoveries and 33

  2. Leo A : A late-blooming survivor of the epoch of reionization in the local group

    NARCIS (Netherlands)

    Cole, Andrew A.; Skillman, Evan D.; Tolstoy, Eline; Gallagher, John S.; Aparicio, Antonio; Dolphin, Andrew E.; Gallart, Carme; Hidalgo, Sebastian L.; Saha, Abhijit; Stetson, Peter B.; Weisz, Daniel R.

    2007-01-01

    As part of a major program to use isolated Local Group dwarf galaxies as near-field probes of cosmology, we have obtained deep images of the dwarf irregular galaxy Leo A with the Advanced Camera for Surveys aboard the Hubble Space Telescope. From these images we have constructed a color-magnitude

  3. The absence of diffuse gas around the dwarf spheroidal galaxy Leo I

    CERN Document Server

    Bowen, D V; Ferrara, A; Blades, J C; Brinks, E; Bowen, David V.; Tolstoy, Eline; Ferrara, Andrea; Brinks, Elias

    1996-01-01

    We have obtained spectra of three QSO/AGNs with the GHRS aboard the {\\it Hubble Space Telescope} to search for absorption from low column density gas in the halo of the dwarf spheroidal (dSph) galaxy Leo I. The probe sightlines pass 2.1, 3.7, and 8.1 kpc from the center of the galaxy, but no C IV, Si II, or Si IV absorption is found at the velocity of Leo I. We suggest that the column density of hydrogen which exists within 2 - 4 kpc of the galaxy is $N_H $< 10^{3}$ and $< 10^{4} M_{ødot}$ around Leo I, for simple models in which gas is distributed as a spherical halo, or as a shell, respectively. Although we cannot rule out the possibility that a significant fraction of hot gas exists along the lines of sight, in an ionization state higher than C IV or Si IV absorption lines would reveal, the results leave us with the impression that Leo I is a dSph galaxy which is isolated and inactive at the present epoch, a conclusion at odds with many theories of dwarf galaxy formation and evolution.

  4. The Oldest Stars of the Extremely Metal-Poor Local Group Dwarf Irregular Galaxy Leo A

    CERN Document Server

    Schulte-Ladbeck, R E; Drozdovsky, I O; Greggio, L; Crone, M M; Schulte-Ladbeck, Regina E.; Hopp, Ulrich; Drozdovsky, Igor O.; Greggio, Laura; Crone, Mary M.

    2002-01-01

    We present deep Hubble Space Telescope single-star photometry of Leo A in B, V, and I. Our new field of view is offset from the centrally located field observed by Tolstoy et al. (1998) in order to expose the halo population of this galaxy. We report the detection of metal-poor red horizontal branch stars, which demonstrate that Leo A is not a young galaxy. In fact, Leo A is as least as old as metal-poor Galactic Globular Clusters which exhibit red horizontal branches, and are considered to have a minimum age of about 9 Gyr. We discuss the distance to Leo A, and perform an extensive comparison of the data with stellar isochrones. For a distance modulus of 24.5, the data are better than 50% complete down to absolute magnitudes of 2 or more. We can easily identify stars with metallicities between 0.0001 and 0.0004, and ages between about 5 and 10 Gyr, in their post-main-sequence phases, but lack the detection of main-sequence turnoffs which would provide unambiguous proof of ancient (>10 Gyr) stellar generation...

  5. Leo A : A late-blooming survivor of the epoch of reionization in the local group

    NARCIS (Netherlands)

    Cole, Andrew A.; Skillman, Evan D.; Tolstoy, Eline; Gallagher, John S.; Aparicio, Antonio; Dolphin, Andrew E.; Gallart, Carme; Hidalgo, Sebastian L.; Saha, Abhijit; Stetson, Peter B.; Weisz, Daniel R.

    2007-01-01

    As part of a major program to use isolated Local Group dwarf galaxies as near-field probes of cosmology, we have obtained deep images of the dwarf irregular galaxy Leo A with the Advanced Camera for Surveys aboard the Hubble Space Telescope. From these images we have constructed a color-magnitude di

  6. Establishing a Robotic, LEO-to-GEO Satellite Servicing Infrastructure as an Economic Foundation for Exploration

    Science.gov (United States)

    Horsham, Gary A. P.; Schmidt, George R.; Gilland, James H.

    2010-01-01

    The strategy for accomplishing civilian exploration goals and objectives is in the process of a fundamental shift towards a potential new approach called Flexible Path. This paper suggests that a government-industry or public-private partnership in the commercial development of low Earth orbit to geostationary orbit (LEO-to-GEO (LTG)) space, following or in parallel with the commercialization of Earth-to-LEO and International Space Station (ISS) operations, could serve as a necessary, logical step that can be incorporated into the flexible path approach. A LTG satellite-servicing infrastructure and architecture concept is discussed within this new strategic context. The concept consists of a space harbor that serves as a transport facility for a fleet of specialized, fully- or semi-autonomous robotic servicing spacecraft. The baseline, conceptual system architecture is composed of a space harbor equipped with specialized servicer spacecraft; a satellite command, communication, and control system; a parts station; a fuel station or depot; and a fuel/parts replenishment transport. The commercial servicer fleet would consist of several types of spacecraft, each designed with specialized robotic manipulation subsystems to provide services such as refueling, upgrade, repair, inspection, relocation, and removal. The space harbor is conceptualized as an ISS-type, octagonal truss structure equipped with radiation tolerant subsystems. This space harbor would be primarily capable of serving as an operational platform for various commercially owned and operated servicer spacecraft positioned and docked symmetrically on four of the eight sides. Several aspects of this concept are discussed, such as: system-level feasibility in terms of ISS-truss-type infrastructure and subsystems emplacement and maintenance between LEO and GEO; infrastructure components assembly in LEO, derived from ISS assembly experience, and transfer to various higher orbital locations; the evolving Earth

  7. Atividade antibacteriana de Óleos Essenciais sobre Streptococcus mutans e Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    I.C.M. Freire

    2014-01-01

    Full Text Available Este trabalho objetivou avaliar a ação antimicrobiana in vitro dos óleos essenciais de Ocimum basilicum (Manjericão Exótico, Thymus vulgaris (Tomilho Branco, e de Cinnamomum cassia (Canela da China sobre cepas bacterianas de Streptococcus mutans (ATCC 25175 e Staphylococcus aureus (ATCC 25923. A atividade antibacteriana dos óleos essenciais foi determinada pela Concentração Inibitória Mínima (CIM e a Concentração Bactericida Mínima (CBM através da técnica de microdiluição e do esgotamento. Para a CIM, foram utilizadas placas de 96 poços e inseriu-se 100µL de caldo BHI, 100µL da diluição dos óleos essenciais no primeiro poço e 10µL da suspensão bacteriana (1,5x10(6 microrganismos/mL. Realizou-se a diluição seriada partindo-se da concentração inicial de 8% até 0,0625%. A CIM correspondeu à última diluição na qual não foi verificada a presença de bactérias. Para obter a CBM, realizou-se a semeadura em Ágar Miller-Hinton das diluições correspondentes a CIM, 2CIM e 4CIM. As placas foram incubadas a 37º C em estufa bacteriológica por 24 horas. Os testes foram realizados em triplicata tendo a clorexidina como controle positivo. Para S. aureus (ATCC 25923 a CIM e CBM dos óleos essenciais de C. cassia, O. basilicum e T. vulgaris foram 0,0625%, 4% e 0,0625%, respectivamente. Para S. mutans a CIM e a CBM dos óleos essenciais de C. cassia e T. vulgaris foram 0,125% e 0,25%, respectivamente. Já a CIM do O. basilicum foi 4% e não apresentou ação bactericida. Conclui-se que os óleos essenciais avaliados apresentaram ação antibacteriana frente a cepas de S. mutans e S. aureus, sendo que os menores valores de CIM e de CBM foram provenientes dos óleos de C. cassia e T. vulgaris.

  8. Desenvolvimento da camomila, rendimento e qualidade do óleo essencial em diferentes idades de colheita

    Directory of Open Access Journals (Sweden)

    W. Amaral

    2014-06-01

    Full Text Available A camomila é uma planta herbácea, anual e aromática com várias propriedades medicinais. No Brasil, vem sendo cultivada em área representativa na região Sul devido, principalmente, às exigências climáticas da espécie, e por ter sido introduzida por imigrantes europeus nesta região. A colheita da camomila é realizada em várias colheitas, contudo, a idade adequada da planta para o início desta atividade, objetivado a maior produção de capítulos florais, bem como o rendimento e qualidade de óleos essenciais, ainda não foi determinada para a espécie. Neste trabalho, investigou-se o efeito de diferentes épocas de colheita no desenvolvimento de capítulos florais e no acúmulo e qualidade do óleo essencial da camomila. O experimento foi conduzido no município de Piraquara (PR. O delineamento experimental foi inteiramente casualizado, com cinco tratamentos (85, 92, 99, 106 e 113 dias após a emergência das plântulas e cinco repetições. Após cada colheita, avaliou-se o acúmulo de massa seca de capítulos, rendimento, produção e composição do óleo essencial. A extração de óleo foi realizada por hidrodestilação e as amostras analisadas por cromatografia gasosa. Concluiu-se que aos 85 dias após a emergência (DAE os capítulos apresentaram maior rendimento de óleo. Porém, após três semanas ocorreu a maior produção de massa de capítulos, resultando em maiores médias de produtividade de óleo essencial. A partir de 113 DAE houve redução do rendimento de óleo essencial e no teor de alguns constituintes.

  9. The Oldest Stars of the Extremely Metal-Poor Local Group Dwarf Irregular Galaxy Leo A

    Science.gov (United States)

    Schulte-Ladbeck, Regina E.; Hopp, Ulrich; Drozdovsky, Igor O.; Greggio, Laura; Crone, Mary M.

    2002-08-01

    We present deep Hubble Space Telescope (HST) single-star photometry of Leo A in B, V, and I. Our new field of view is offset from the centrally located field observed by Tolstoy et al. in order to expose the halo population of this galaxy. We report the detection of metal-poor red horizontal branch stars, which demonstrate that Leo A is not a young galaxy. In fact, Leo A is as least as old as metal-poor Galactic Globular Clusters that exhibit red horizontal branches and are considered to have a minimum age of about 9 Gyr. We discuss the distance to Leo A and perform an extensive comparison of the data with stellar isochrones. For a distance modulus of 24.5, the data are better than 50% complete down to absolute magnitudes of 2 or more. We can easily identify stars with metallicities between 0.0001 and 0.0004, and ages between about 5 and 10 Gyr, in their post-main-sequence phases, but we lack the detection of main-sequence turnoffs that would provide unambiguous proof of ancient (>10 Gyr) stellar generations. Blue horizontal branch stars are above the detection limits but difficult to distinguish from young stars with similar colors and magnitudes. Synthetic color-magnitude diagrams show it is possible to populate the blue horizontal branch in the halo of Leo A. The models also suggest ~50% of the total astrated mass in our pointing to be attributed to an ancient (>10 Gyr) stellar population. We conclude that Leo A started to form stars at least about 9 Gyr ago. Leo A exhibits an extremely low oxygen abundance, only 3% of solar, in its ionized interstellar medium. The existence of old stars in this very oxygen-deficient galaxy illustrates that a low oxygen abundance does not preclude a history of early star formation. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  10. LEO P: HOW MANY METALS CAN A VERY LOW MASS, ISOLATED GALAXY RETAIN?

    Energy Technology Data Exchange (ETDEWEB)

    McQuinn, Kristen B. W.; Skillman, Evan D. [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Dolphin, Andrew [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Salzer, John J.; Rhode, Katherine L. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Adams, Elizabeth A. K. [ASTRON, the Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA, Dwingeloo (Netherlands); Berg, Danielle [Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin Milwaukee, 1900 East Kenwood Boulevard, Milwaukee, WI 53211 (United States); Giovanelli, Riccardo; Haynes, Martha P., E-mail: kmcquinn@astro.as.utexas.edu [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States)

    2015-12-20

    Leo P is a gas-rich dwarf galaxy with an extremely low gas-phase oxygen abundance (3% solar). The isolated nature of Leo P enables a quantitative measurement of metals lost solely due to star formation feedback. We present an inventory of the oxygen atoms in Leo P based on the gas-phase oxygen abundance measurement, the star formation history (SFH), and the chemical enrichment evolution derived from resolved stellar populations. The SFH also provides the total amount of oxygen produced. Overall, Leo P has retained 5% of its oxygen; 25% of the retained oxygen is in the stars while 75% is in the gas phase. This is considerably lower than the 20%–25% calculated for massive galaxies, supporting the trend for less efficient metal retention for lower-mass galaxies. The retention fraction is higher than that calculated for other alpha elements (Mg, Si, Ca) in dSph Milky Way satellites of similar stellar mass and metallicity. Accounting only for the oxygen retained in stars, our results are consistent with those derived for the alpha elements in dSph galaxies. Thus, under the assumption that the dSph galaxies lost the bulk of their gas mass through an environmental process such as tidal stripping, the estimates of retained metal fractions represent underestimates by roughly a factor of four. Because of its isolation, Leo P provides an important datum for the fraction of metals lost as a function of galaxy mass due to star formation.

  11. Alfalfa discovery of the nearby gas-rich dwarf galaxy Leo P. IV. Distance measurement from LBT optical imaging

    Energy Technology Data Exchange (ETDEWEB)

    McQuinn, Kristen B. W.; Skillman, Evan D.; Berg, Danielle [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Salzer, John J.; Rhode, Katherine L. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Adams, Elizabeth A. K.; Giovanelli, Riccardo; Haynes, Martha P. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Dolphin, Andrew, E-mail: kmcquinn@astro.umn.edu, E-mail: skillman@astro.umn.edu, E-mail: berg@astro.umn.edu, E-mail: jcannon@macalester.edu, E-mail: rhode@astro.indiana.edu, E-mail: slaz@astro.indiana.edu, E-mail: betsey@astro.cornell.edu, E-mail: riccardo@astro.cornell.edu, E-mail: haynes@astro.cornell.edu [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States)

    2013-12-01

    Leo P is a low-luminosity dwarf galaxy discovered through the blind H I Arecibo Legacy Fast ALFA survey. The H I and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with both active star formation and an underlying older population, as well as an extremely low oxygen abundance. Here, we measure the distance to Leo P by applying the tip of the red giant branch (TRGB) distance method to photometry of the resolved stellar population from new Large Binocular Telescope V and I band imaging. We measure a distance modulus of 26.19{sub −0.50}{sup +0.17} mag corresponding to a distance of 1.72{sub −0.40}{sup +0.14} Mpc. Although our photometry reaches 3 mag below the TRGB, the sparseness of the red giant branch yields higher uncertainties on the lower limit of the distance. Leo P is outside the Local Group with a distance and velocity consistent with the local Hubble flow. While located in a very low-density environment, Leo P lies within ∼0.5 Mpc of a loose association of dwarf galaxies which include NGC 3109, Antlia, Sextans A, and Sextans B, and 1.1 Mpc away from its next nearest neighbor, Leo A. Leo P is one of the lowest metallicity star-forming galaxies known in the nearby universe, comparable in metallicity to I Zw 18 and DDO 68, but with stellar characteristics similar to dwarf spheriodals (dSphs) in the Local Volume such as Carina, Sextans, and Leo II. Given its physical properties and isolation, Leo P may provide an evolutionary link between gas-rich dwarf irregular galaxies and dSphs that have fallen into a Local Group environment and been stripped of their gas.

  12. Boro, cultivar e local de cultivo afetam a produtividade de aquênios e óleo de girassol?

    OpenAIRE

    Silva,Fred Denilson Barbosa da

    2012-01-01

    Na cultura do girassol, a adubação com boro (B) tem sido decisiva na produtividade de aquênios e de óleo. A escolha da cultivar e da época de semeadura é fundamental para atingir altas produtividades de aquênios com óleo de melhor qualidade. Objetivou-se, com este trabalho, avaliar o estado nutricional, a produtividade de aquênios e o teor de óleo de três cultivares de girassol como variáveis de doses de B e de dois locais de cultivo (Januária- MG e Coimbra-MG). Foram realizados quatro experi...

  13. Criação de valor sustentável e o óleo de palma no Brasil

    OpenAIRE

    Almeida, Julio Ribeiro

    2012-01-01

    A produção de óleo de palma expandiu-se consideravelmente nas últimas décadas e atualmente o óleo de palma é o óleo vegetal mais comercializado do mundo. Dentre outros fatores, a maior produtividade da cultura e os menores custos de produção explicam o crescimento. Os grandes produtores mundiais, contudo, destruíram grandes áreas de floresta para acomodar o crescimento da plantação e se utilizaram de técnicas de cultivo que trouxeram severos impactos ambientais. Campanhas lider...

  14. Estudo de modelos composicionais de óleo na injeção contínua de vapor

    OpenAIRE

    Cavalcante, Liara Tavares

    2011-01-01

    O objetivo da recuperação térmica é aquecer o reservatório e o óleo nele existente para aumentar a sua recuperação. Na Bacia Potiguar existem vários reservatórios de óleos pesados cuja energia de recuperação primária nos fornece uma vazão de óleo pequena, o que torna tais reservatórios ótimos candidatos para aplicação de um método de recuperação avançada de petróleo, especialmente o térmico. A injeção de vapor pode ocorrer de forma cíclica ou contínua. A injeção de vapor contínua ocorre at...

  15. Reciclo-óleo: do óleo de cozinha ao sabão ecológico, um projeto de educação ambiental

    Directory of Open Access Journals (Sweden)

    Maria Isabel Morgan Martins

    2016-10-01

    Full Text Available O consumo de óleo faz parte do dia-a-dia das famílias, restaurantes, indústrias e com ele o descarte incorreto do óleo de cozinha usado (OCU se torna um grave problema ambiental. Quando despejado no lixo comum impermeabiliza e contamina o solo, porque a decomposição aumenta o efeito estufa, na rede de esgoto compromete as tubulações das residências e das cidades e ao atingir os rios forma uma película na água que impede a passagem de luz e oxigênio a flora e a fauna aquática. Objetivo: é promover a educação ambiental para o descarte correto e a reciclagem do óleo de cozinha usado, transformando-o em sabão em barra ecológico, gerando renda e sustentabilidade. Método/ atividades de extensão: o projeto apresenta duas linhas bem definidas à educação ambiental e o desenvolvimento de receitas que transformam do OCU em sabão em barra ecológico. O projeto educa para a consciência e responsabilidade ambiental a diferentes grupos da comunidade, ensina e orienta a importância de dar o destino correto ao OCU, bem como, a reciclagem com sustentabilidade, criando alternativa de geração de renda. Desde 2010, as oficinas foram realizadas em diferentes bairros, escolas e empresas dos municípios da grande Porto Alegre, RS. As receitas foram desenvolvidas no laboratório do campus da ULBRA Gravataí, e apresentam baixo custo, para a fabricação “caseira” do sabão ecológico. O primeiro processo é educar com consciência ambiental. Considerações finais: o reciclo-óleo contribui para o combate à poluição e manutenção dos recursos naturais. Portanto, com ações de educação em saúde é possível refletir positivamente na preservação do meio ambiente, contribuindo, dessa forma, para o desenvolvimento sustentável e para a promoção da saúde das cidades.

  16. Noored ja oreoolid / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Köler Prize'i nominentide näitus Eesti Kaasaegse Kunsti Muuseumis 12. juunini 2011. Köler Prize'i sai skulptor ja installatsioonikunstnik Jevgeni Zolotko, publikupreemia maalikunstnik Tõnis Saadoja. Eesti Kunstiakadeemia noore kunstniku preemia pälvis vabade kunstide teaduskonna bakalaureusetaseme lõpetajatest skulptor Ulla Juske, magistritaseme lõpetajatest maalikunstnik Kristi Kongi ja vabakunstnik Eva Labotkin. Premeeritute loomingust

  17. Taastuvenergia kasutamine Rõuges / Tanel Lukason

    Index Scriptorium Estoniae

    Lukason, Tanel

    2005-01-01

    Rõuge piirkond on hea näide, kuidas oskusliku tegutsemisega on võimalik saavutada märkimisväärset positiivset efekti biomassi, veejõu, maasse akumuleeritud soojuse ja otsese päikesekiirguse kasutamisel elektri ning soojuse tootmiseks. Kaart. Fotod. Skeem

  18. Disain parandab maailma / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Taani disainiauhinna INDEX: Award 2011eelžüriile laekus ligi tuhat võistlustööd, millest valiti finaali 61 tööd. Tooted on jaotatud viide kategooriasse - keha, kodu, töö, mäng ja kogukond. Ettevõtmise moto - "Design to Improve Life" ("Disain elu edendamiseks")

  19. Kuidas osta ajalugu/ / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Disainimaailmas levivast trendist - anda kangastele, mööblile jt. esemetele antiikne ja kulunud ilme. Eestit külastanud Andrea Santoni firmas üle 25 aasta kingi vanutanud käsitöölisest Loredano Salvadorist. Itaalia kingafirma omanik Andrea Santoni asutas 2005. a. kooli, kus kunstkäsitöölised annavad noortele edasi oskusteavet kingade valmistamise ja viimistlemise tehnikate kohta

  20. Sekku! Klikka! Mõtesta! / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Rahvusvaheline meediakunsti näitus "Gateways. Kunst ja võrgustunud kultuur" Kumu Kunstimuuseumis 13.05.-25.09.2011. Näitus esitleb 27 Euroopa kunstniku teoseid, mis tegelevad kommunikatsiooni ja võrgustumise teemaga, kuraator Sabine Himmelsbach. Pikemalt eesti kunstniku Timo Tootsi tööst "Memopol II". Näituse koordinaatori ja abikuraatori Ragne Nuka vastused kolmele küsimusele

  1. Sekku! Klikka! Mõtesta! / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Rahvusvaheline meediakunsti näitus "Gateways. Kunst ja võrgustunud kultuur" Kumu Kunstimuuseumis 13.05.-25.09.2011. Näitus esitleb 27 Euroopa kunstniku teoseid, mis tegelevad kommunikatsiooni ja võrgustumise teemaga, kuraator Sabine Himmelsbach. Pikemalt eesti kunstniku Timo Tootsi tööst "Memopol II". Näituse koordinaatori ja abikuraatori Ragne Nuka vastused kolmele küsimusele

  2. Totaalne disainiring Tallinnas / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Rotermanni kvartali elevaatoris näitus "Disaini elevaator", Prooviveskis võistluse "Eesti disain ja elukeskkond 2009" nominentide tööde väljapanek ja rahvusvaheline näitus "BIO esitleb: BIO disainiparemik" (töid Sloveenia tööstusdisaini biennaalilt), jahulao aatriumis näitus "Polish Design. The Essence" 11. okt.-ni. A-Galeriis Maria Valdma näitus "Tolm" 12. okt.-ni. Galeriis Hop tekstiilikunstnik Lylian Meistri ja Katarina Meistri näitus "Erailu" 6. okt.-ni. Galeriis Galerii Kaks tekstiilikunstnik Liivi Leppiku ruumiliste tekstiilipannoode näitus 14. okt.-ni. Eesti Kunstiakadeemia galeriis Eesti Kunstiakadeemia tekstiilikunsti eriala üliõpilaste näitus "Glamuurselt kodutu" 6. okt.-ni

  3. Taastuvenergia kasutamine Rõuges / Tanel Lukason

    Index Scriptorium Estoniae

    Lukason, Tanel

    2005-01-01

    Rõuge piirkond on hea näide, kuidas oskusliku tegutsemisega on võimalik saavutada märkimisväärset positiivset efekti biomassi, veejõu, maasse akumuleeritud soojuse ja otsese päikesekiirguse kasutamisel elektri ning soojuse tootmiseks. Kaart. Fotod. Skeem

  4. Disain muudab maailma / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Taanlaste maailmaparanduslikust disainivõistlusest "INDEX : Award 2009", mille auhinnasaajad on selgunud. Võistlusel osales üle 700 töö, mis eelkõige pakuvad lahendusi kriisikolletes. Kaheksa võistlusel osalenud töö tutvustus. Kodutoodete kategoorias võitis peaauhinna Philipsi säästupliit

  5. Kolm maailma metallis / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Näitused Tallinnas: Maria Valdma "Võõrastemaja" Iida galeriis 31. jaan.-ni 2012, Kaie Partsi retrospektiivnäitus "Metall ja kivi" Vabaduse galeriis 6. dets.-ni 2011, Ülle Kõutsi "Vesi" A-Galeriis 5. dets.-ni 2011

  6. Tagasi puu otsa! / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Puu otsa ehitatud ja puudel rippuvatest majadest. Üle 60 San Francisco kunstniku koostöös sündinud Steampunk Tree House, Takashi Kobayashi loodud puumaja, Toronto arhitektuuri- ja disainiülikooli tudengi Lukasz Kosi disainitud 4TreeHouse, Tom Chudleighi disainitus "Vaba hinge sfäärid", 02 Sustainability Tree House, Romero Studiosi ja Baumraumi puumajad

  7. Narva valmistub maipidustusteks / Tanel Mazur

    Index Scriptorium Estoniae

    Mazur, Tanel, 1971-

    2005-01-01

    Ilmunud ka: Eesti Päevaleht 2. apr., lk. 7 (lühendatud), Narvskaja Gazeta 2. apr., lk. 4. Reformierakond registreeris 9. maiks Euroopa päeva ürituse. Narva sõjaveteranid korraldavad samal päeval miitingu ning ei soovi poliitikute osalemist sellel

  8. Ministrid astusid auku / Tanel Mazur

    Index Scriptorium Estoniae

    Mazur, Tanel, 1971-

    2004-01-01

    Ilmunud ka: Narvskaja Gazeta, 21. okt. 2004, lk. 2. Siseminister Margus Leivo ja regionaalminister Jaan Õunapuu tutvusid Ida-Virumaa visiidi käigus Sillamäe sadama ehitusega ja perspektiiviga ehitada uus sild üle Narva jõe

  9. Noored ja oreoolid / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Köler Prize'i nominentide näitus Eesti Kaasaegse Kunsti Muuseumis 12. juunini 2011. Köler Prize'i sai skulptor ja installatsioonikunstnik Jevgeni Zolotko, publikupreemia maalikunstnik Tõnis Saadoja. Eesti Kunstiakadeemia noore kunstniku preemia pälvis vabade kunstide teaduskonna bakalaureusetaseme lõpetajatest skulptor Ulla Juske, magistritaseme lõpetajatest maalikunstnik Kristi Kongi ja vabakunstnik Eva Labotkin. Premeeritute loomingust

  10. Disain parandab maailma / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Taani disainiauhinna INDEX: Award 2011eelžüriile laekus ligi tuhat võistlustööd, millest valiti finaali 61 tööd. Tooted on jaotatud viide kategooriasse - keha, kodu, töö, mäng ja kogukond. Ettevõtmise moto - "Design to Improve Life" ("Disain elu edendamiseks")

  11. Disain parandab maailma / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Rändnäitus "INDEX : Award Exhibition 2007: winners of tour" Tallinnas Harju tänava haljasalal 19. juulini. Võistlusel INDEX : Award osalevatelt toodetelt oodatakse peale hea väljanägemise, et nad muudaksid elu paremaks

  12. Eha-ehted / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2005-01-01

    Endise A-Galerii ruumides Tallinnas Hobusepea tänaval on avatud uus A-Galerii. Avanäituseks on Eesti Kunstiakadeemia ehteeriala ja Firenze Alchimia ehtekooli ühisnäitus "Hämarus/Twilight". Näituse töödest

  13. Kõige moodsam janu / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Koostööst moekunstnike ja joogitootjate vahel. Prantsuse moekunstniku Jean-Paul Gaultier loomingust sündinud reklaamide seeriast Absolut Legends, Nathalie Rykieli disainitud Diet Coke'i pudelitest ning Jean-Paul Gaultier' ja Christian Lacroix' disainitud Eviani pudelitest

  14. Kolm maailma metallis / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2011-01-01

    Näitused Tallinnas: Maria Valdma "Võõrastemaja" Iida galeriis 31. jaan.-ni 2012, Kaie Partsi retrospektiivnäitus "Metall ja kivi" Vabaduse galeriis 6. dets.-ni 2011, Ülle Kõutsi "Vesi" A-Galeriis 5. dets.-ni 2011

  15. Telekommunikatsioon vallutas edetabeli / Tanel Raig

    Index Scriptorium Estoniae

    Raig, Tanel, 1975-

    2003-01-01

    Autor analüüsib telekommunikatsioonisektori ettevõtete juhtpositsiooni põhjuseid Eesti Edukaimate Ettevõtete edetabelis ja järeldab, et telekommunikatsioon on tõusnud Eesti edukaimaks ja kiiremini arenevaks valdkonnaks. Lisad: Suurimad tõusjad TOP 100 esikümnes; Suurimad langejad TOP 100 esikümnes

  16. Kõige moodsam janu / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Koostööst moekunstnike ja joogitootjate vahel. Prantsuse moekunstniku Jean-Paul Gaultier loomingust sündinud reklaamide seeriast Absolut Legends, Nathalie Rykieli disainitud Diet Coke'i pudelitest ning Jean-Paul Gaultier' ja Christian Lacroix' disainitud Eviani pudelitest

  17. Disain parandab maailma / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Rändnäitus "INDEX : Award Exhibition 2007: winners of tour" Tallinnas Harju tänava haljasalal 19. juulini. Võistlusel INDEX : Award osalevatelt toodetelt oodatakse peale hea väljanägemise, et nad muudaksid elu paremaks

  18. Tagasi puu otsa! / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Puu otsa ehitatud ja puudel rippuvatest majadest. Üle 60 San Francisco kunstniku koostöös sündinud Steampunk Tree House, Takashi Kobayashi loodud puumaja, Toronto arhitektuuri- ja disainiülikooli tudengi Lukasz Kosi disainitud 4TreeHouse, Tom Chudleighi disainitus "Vaba hinge sfäärid", 02 Sustainability Tree House, Romero Studiosi ja Baumraumi puumajad

  19. Totaalne disainiring Tallinnas / Tanel Veenre

    Index Scriptorium Estoniae

    Veenre, Tanel, 1977-

    2009-01-01

    Rotermanni kvartali elevaatoris näitus "Disaini elevaator", Prooviveskis võistluse "Eesti disain ja elukeskkond 2009" nominentide tööde väljapanek ja rahvusvaheline näitus "BIO esitleb: BIO disainiparemik" (töid Sloveenia tööstusdisaini biennaalilt), jahulao aatriumis näitus "Polish Design. The Essence" 11. okt.-ni. A-Galeriis Maria Valdma näitus "Tolm" 12. okt.-ni. Galeriis Hop tekstiilikunstnik Lylian Meistri ja Katarina Meistri näitus "Erailu" 6. okt.-ni. Galeriis Galerii Kaks tekstiilikunstnik Liivi Leppiku ruumiliste tekstiilipannoode näitus 14. okt.-ni. Eesti Kunstiakadeemia galeriis Eesti Kunstiakadeemia tekstiilikunsti eriala üliõpilaste näitus "Glamuurselt kodutu" 6. okt.-ni

  20. Effect of KOH concentration on LEO cycle life of IPV nickel-hydrogen flight cell - Update II

    Science.gov (United States)

    Smithrick, John J.; Hall, Stephen W.

    1992-01-01

    An update of validation test results confirming the breakthrough in LEO cycle life of nickel-hydrogen cells containing 26 percent KOH electrolyte is presented. A breakthrough in the LEO cycle life of individual pressure vessel (IPV) nickel-hydrogen cells has been previously reported. The cycle life of boiler plate cells containing 26 percent potassium hydroxide (KOH) electrolyte was about 40,000 LEO cycles, compared to 3500 cycles for cells containing 31 percent KOH. The cycle regime was a stressful accelerated LEO, which consisted of a 27.5 min charge followed by a 17.5 min discharge (2X normal rate). The depth-of-discharge was 80 percent. Six 48-Ah Hughes recirculation design IPV nickel-hydrogen flight battery cells are being evaluated. Three of the cells contain 26 percent KOH (test cells), and three contain 31 percent KOH (control cells). They are undergoing real time LEO cycle life testing. The cycle regime is a 90-min LEO orbit consisting of a 54-min charge followed by a 36-min discharge. The depth-of-discharge is 80 percent. The cell temperature is maintained at 10 C. The three 31 percent KOH cells failed (cycles 3729, 4165, and 11355). One of the 26 percent KOH cells failed at cycle 15314. The other two 26 percent KOH cells were cycled for over 16,000 cycles during the continuing test.

  1. Projecto educativo Leo Brouwer - Contributos para a pedagogia guitarrística

    OpenAIRE

    Marques, Tiago Emanuel Cassola

    2012-01-01

    O presente trabalho propõe-se apresentar a figura de Leo Brouwer enquanto pedagogo no âmbito da pedagogia guitarrística, para além de abordar a sua relevância como guitarrista, maestro e compositor, em particular a sua escrita para guitarra. Será feita uma recensão analítica dos antecedentes históricos da guitarra, partindo de Giuliani até Leo Brouwer, e obtidas conclusões acerca da pesquisa e análise da sua obra didáctica, das suas reflexões teóricas e da sua prática de ensino em contexto...

  2. Zero-difference and single-difference precise orbit determination for LEO using GPS

    Institute of Scientific and Technical Information of China (English)

    PENG DongJu; WU Bin

    2007-01-01

    Various methods for precise orbit determination (POD) of low earth orbiters (LEO) are briefly introduced in this paper. Based on the software named SHORD-III developed by our institute, single-difference (SD) and zero-difference (ZD) dynamic POD based on LEO carrying an on-board GPS receiver is mainly discussed. The approaches are tested using real GRACE data (November 5-25, 2002) and independently validated with Satellite Laser Ranging (SLR) measurements over the same 21 days. Comparisons with the scientific orbits provided by GFZ indicate that the SD POD RMS accuracy can achieve 5, 10 and 6 cm in radial, along and cross the track, and the ZD POD RMS accuracy can achieve 4, 8 and 4 cm in radial, along and cross the track. SLR validation shows that SD POD accuracy is better than 8 cm in distance, and ZD POD accuracy is better than 6 cm.

  3. Dynamic channel reservation scheme based on priorities in LEO satellite systems

    Institute of Scientific and Technical Information of China (English)

    Jian Zhou; Xiaoguo Ye; Yong Pan; Fu Xiao; Lijuan Sun

    2015-01-01

    According to low earth orbit (LEO) satel ite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresh-olds for reserved channels is the key of this strategy. In order to obtain the optimal thresholds, the traffic is predicted based on the high-speed deterministic movement property of LEO satel ites firstly. Then, a channel al ocation model based on Markov is es-tablished. Final y, the solution of the model is obtained based on the genetic algorithm. Without user location, this strategy effec-tively reduces handover failures and improves channel utilization by adjusting dynamical y the thresholds according to traffic condi-tions. The simulation results show that the system’s overal quality of service can be improved by this strategy.

  4. Leo den Store: Prædiken på st. Laurentius' dag

    DEFF Research Database (Denmark)

    Willert, Niels

    1992-01-01

    Oversættelse af prædiken holdt af den kendte pave Leo den store i 400-tallet. Prædikenen forholder sig til Sankt Laurentius og hans martyrdød.Oversættelsen er et bidrag i en samling af prædikener fra oldkirken. Bogen har en indledning ved professor dr.theol. Christian Thodberg.......Oversættelse af prædiken holdt af den kendte pave Leo den store i 400-tallet. Prædikenen forholder sig til Sankt Laurentius og hans martyrdød.Oversættelsen er et bidrag i en samling af prædikener fra oldkirken. Bogen har en indledning ved professor dr.theol. Christian Thodberg....

  5. Automating Access Control Logics in Simple Type Theory with LEO-II (Techreport)

    CERN Document Server

    Benzmueller, Christoph

    2009-01-01

    Garg and Abadi recently proved that prominent access control logics can be translated in a sound and complete way into modal logic S4. We have previously outlined how normal multimodal logics, including monomodal logics K and S4, can be embedded in simple type theory (which is also known as higher-order logic) and we have demonstrated that the higher-order theorem prover LEO-II can automate reasoning in and about them. In this paper we combine these results and describe a sound and complete embedding of different access control logics in simple type theory. Employing this framework we show that the off the shelf theorem prover LEO-II can be applied to automate reasoning in prominent access control logics.

  6. Megaíleo chagásico: Descrição de um caso

    Directory of Open Access Journals (Sweden)

    Maricéa Rychuv Santos

    1988-08-01

    Full Text Available É apresentado um caso de megaíleo de natureza chagásica. O paciente, portador da Doença de Chagas, branco com 41 anos, apresentava história de 3 anos de episódios de eólicas abdominais, distensão e diarréia, que foram se tornando mais intensas e mais freqüentes. Fora das crises, apresentava-se assintomático. O diagnóstico de megaíleo foi estabelecido por meio do estudo radiológico contrastado do intestino delgado. O estudo histológico realizado em fragmento obtido à intervenção cirúrgica mostrou diminuição do número de células ganglionares dos plexos mientéricos.

  7. Optimal GEO lasercomm terminal field of view for LEO link support

    Science.gov (United States)

    Hindman, Charles W.; Hunt, Jeffrey P.; Engberg, Brian S.; Walchko, Kevin J.

    2006-02-01

    As alternatives to the traditional gimbaled terminal design, future satellite based laser communications terminals are envisioned that utilize a wide field of view or field of regard (WFOV/WFOR). This approach can be advantageous in situations requiring rapid switching between user terminals, support for multiple terminals simultaneously (via TDMA, SDMA or WDMA) or other non-standard mission requirements. However, a traditional gimbaled terminal has the capability to continuously track a single user over very large angles, such as the 18-20° spanned by a LEO satellite as seen from GEO. WFOV/WFOR designs face increasing cost and/or complexity issues with each incremental increase in angular coverage. The methodology and inputs for a trade study are presented here that attempts to maximize the available connectivity to a LEO satellite while minimizing cost and complexity metrics by choosing an optimal FOV/FOR size for a GEO terminal.

  8. Adaptive Optics for Satellite and Debris Imaging in LEO and GEO

    Science.gov (United States)

    Copeland, M.; Bennet, F.; Zovaro, A.; Riguat, F.; Piatrou, P.; Korkiakoski, V.; Smith, C.

    2016-09-01

    The Research School of Astronomy and Astrophysics (RSAA) at the Australian National University has developed and Adaptive Optics (AO) system for satellite and debris imaging in low Earth orbit (LEO) and geostationary orbit (GEO). In LEO the size, shape and orientation of objects will be measured with resolution of 50 cm for objects at 800 km range at an 800 nm imaging wavelength. In GEO satellite position will be measured using precision astrometry of nearby stars. We use an AO system with a deformable mirror (DM) of 277 actuators and Shack-Hartmann wavefront sensor operating at 2 kHz. Imaging is performed at a rate of >30 Hz to reduce image blur due to tip-tilt and rotation. We use two imaging modes; a high resolution mode to obtain Nyquist sampled images and a acquisition mode with 75 arcsecond field of view to aid in finding targets.

  9. LeoTask: a fast, flexible and reliable framework for computational research

    OpenAIRE

    Zhang, Changwang; Zhou, Shi; Chain, Benjamin M

    2015-01-01

    LeoTask is a Java library for computation-intensive and time-consuming research tasks. It automatically executes tasks in parallel on multiple CPU cores on a computing facility. It uses a configuration file to enable automatic exploration of parameter space and flexible aggregation of results, and therefore allows researchers to focus on programming the key logic of a computing task. It also supports reliable recovery from interruptions, dynamic and cloneable networks, and integration with th...

  10. Óleo essencial de Chenopodium ambrosioides L.: estado da arte

    Directory of Open Access Journals (Sweden)

    Rafaela Damasceno Sá

    2015-10-01

    Full Text Available Chenopodium ambrosioides L. é uma erva aromática amplamente distribuída ao longo da América, África e também em países da Europa. No Brasil, a planta é popularmente conhecida como mastruz. Tem sido utilizada pela população como anti-helmíntica e para tratamentos de gripe. O óleo essencial das folhas é o componente mais conhecido da planta e de grande importância científica. As propriedades terapêuticas da planta são geralmente atribuídas ao óleo essencial pelos investigadores. Este trabalho traz uma revisão da literatura sobre o óleo essencial de C. ambrosioides, com ênfase nos seus constituintes químicos, atividade biológica e aspectos toxicológicos.Palavras-chave: Ascaridol. Chenopodicaeae. Chenopodium ambrosioides. Mastruz. Óleo essencial. ABSTRACT Chenopodium ambrosioides L. is an aromatic herb widely distributed throughout the Americas, Africa and also in European countries. In Brazil, the plant is popularly known as mastruz. It has been used by the population as anthelmintic and in the treatment of influenza. The essential oil of the leaves is the most familiar component of the plant and of great scientific importance. The therapeutic properties of the plant are generally attributed to the essential oil. This paper reviews the literature on the essential oil of C. ambrosioides, with emphasis on its chemical constituents, biological activity and toxicological aspects.Keywords: Ascaridole. Chenopodiaceae. Chenopodium ambrosioides. Essential Oil. Mastruz.

  11. A Search for Stellar Dust Production in Leo P, a Nearby Analog of High Redshift Galaxies

    Science.gov (United States)

    Boyer, Martha; McDonald, Iain; McQuinn, Kristen; Skillman, Evan; Sonneborn, George; Srinivasan, Sundar; van Loon, Jacco Th.; Zijlstra, Albert; Sloan, Greg

    2016-08-01

    The origin of dust in the early Universe is a matter of debate. One of the main potential dust contributors are Asymptotic Giant Branch (AGB) stars, and several studies have been devoted to investigating whether and how AGB dust production changes in metal-poor environments. Of particular interest are the most massive AGB stars (8-10 Msun), which can in principle enter the dust-producing phase systems reachable in the infrared and to the short lifetimes of these stars. The recently discovered galaxy Leo P provides an irresistible opportunity to search for these massive AGB stars: Leo P is a gas-rich, star-forming galaxy, it is nearby enough for resolved star photometry with Spitzer, and its interstellar medium is 0.4 dex more metal-poor than any other accessible star-forming galaxy. Models predict ~3 massive AGB stars may be present in Leo P, and optical HST observations reveal 7 candidates. We propose to use Spitzer to determine whether these stars are dusty, providing valuable constraints to the dust contribution from AGB stars up to at least redshift 3.2, or 11.7 Gyr ago, when massive spheroidals and Galactic globular clusters were still forming. This is a gain of 2.8 Gyr compared to other accessible galaxies. We also request 1 orbit of joint HST time to confirm whether the AGB candidates in Leo P are indeed massive AGB stars belonging to the galaxy. These observations will provide information crucial for potential JWST followup spectroscopy.

  12. A Model for the Handover Traffic and Channel Occupancy Time in LEO Satellite Networks

    Institute of Scientific and Technical Information of China (English)

    WangJingyu; YaoYongyang

    1995-01-01

    This paper presents a method to determine the parameters of the traffic model for the LEO satellite networks-the handover traffic and the mean channel occupancy time.The main idea is that the handover traffic is mainly due to the movement of the satellites and the velocity of the mobile terminals and earth rotation is ignored.The performance level can be calculated accord-ing to different handover queuing model.

  13. Serum biochemical study of major elements of captive Asiatic Lions Panthera leo persica

    Directory of Open Access Journals (Sweden)

    R.G. Jani

    2010-02-01

    Full Text Available The serum biochemistry of captive Asiatic Lions Panthera leo persica in India has not been studied in depths. We report here the results of an analysis of a large number of individuals with the aim of providing reference ranges for major serological parameters in male and female Asiatic lions in health and diseases. This information will be of use to zoo veterinarians and pathologists.

  14. Prediction of Retained Capacity and EODV of Li-ion Batteries in LEO Spacecraft Batteries

    OpenAIRE

    2010-01-01

    In resent years ANN is widely reported for modeling in different areas of science including electro chemistry. This includes modeling of different technological batteries such as lead acid battery, Nickel cadmium batteries etc. Lithium ion batteries are advance battery technology which satisfy most of the space mission requirements. Low earth orbit (LEO)space craft batteries undergo large number of charge discharge cycles (about 25000 cycles)compared to other ground level or space application...

  15. Positive immunolabelling for feline infectious peritonitis in an African lion (Panthera leo) with bilateral panuveitis.

    Science.gov (United States)

    Mwase, M; Shimada, K; Mumba, C; Yabe, J; Squarre, D; Madarame, H

    2015-01-01

    A 15-year-old male African lion (Panthera leo) was presented with blindness due to bilateral panuveitis with retinal detachment. Feline coronavirus (FCoV) antigen was identified immunohistochemically in ocular macrophages, consistent with a diagnosis of feline infectious peritonitis (FIP) infection. This is the first report of FIP in an African lion and the first report of ocular FIP in a non-domestic felid.

  16. Controlling the Growth of Future LEO Debris Populations with Active Debris Removal

    Science.gov (United States)

    Liou, J.-C.; Johnson, N. L.; Hill, N. M.

    2008-01-01

    Active debris removal (ADR) was suggested as a potential means to remediate the low Earth orbit (LEO) debris environment as early as the 1980s. The reasons ADR has not become practical are due to its technical difficulties and the high cost associated with the approach. However, as the LEO debris populations continue to increase, ADR may be the only option to preserve the near-Earth environment for future generations. An initial study was completed in 2007 to demonstrate that a simple ADR target selection criterion could be developed to reduce the future debris population growth. The present paper summarizes a comprehensive study based on more realistic simulation scenarios, including fragments generated from the 2007 Fengyun-1C event, mitigation measures, and other target selection options. The simulations were based on the NASA long-term orbital debris projection model, LEGEND. A scenario, where at the end of mission lifetimes, spacecraft and upper stages were moved to 25-year decay orbits, was adopted as the baseline environment for comparison. Different annual removal rates and different ADR target selection criteria were tested, and the resulting 200-year future environment projections were compared with the baseline scenario. Results of this parametric study indicate that (1) an effective removal strategy can be developed based on the mass and collision probability of each object as the selection criterion, and (2) the LEO environment can be stabilized in the next 200 years with an ADR removal rate of five objects per year.

  17. Cost Analysis of Algorithm Based Billboard Manger Based Handover Method in LEO satellite Networks

    Directory of Open Access Journals (Sweden)

    Suman Kumar Sikdar

    2012-12-01

    Full Text Available Now-a-days LEO satellites have an important role in global communication system. They have some advantages like low power requirement and low end-to-end delay, more efficient frequency spectrum utilization between satellites and spot beams over GEO and MEO. So in future they can be used as a replacement of modern terrestrial wireless networks. But the handover occurrence is more due to the speed of the LEOs. Different protocol has been proposed for a successful handover among which BMBHO is more efficient. But it had a problem during the selection of the mobile node during handover. In our previous work we have proposed an algorithm so that the connection can be established easily with the appropriate satellite. In this paper we will evaluate the mobility management cost of Algorithm based Billboard Manager Based Handover method (BMBHO. A simulation result shows that the cost is lower than the cost of Mobile IP of SeaHO-LEO and PatHOLEO

  18. Variability and star formation in Leo T, the lowest luminosity star-forming galaxy known today

    CERN Document Server

    Clementini, Gisella; Ramos, Rodrigo Contreras; Federici, Luciana; Ripepi, Vincenzo; Marconi, Marcella; Tosi, Monica; Musella, Ilaria

    2012-01-01

    We present results from the first combined study of variable stars and star formation history (SFH) of the Milky Way (MW) "ultra-faint" dwarf (UFD) galaxy Leo T, based on F606W and F814W multi-epoch archive observations obtained with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. We have detected 14 variable stars in the galaxy. They include one fundamental-mode RR Lyrae star and 10 Anomalous Cepheids with periods shorter than 1 day, thus suggesting the occurrence of multiple star formation episodes in this UFD, of which one about 10 Gyr ago produced the RR Lyrae star. A new estimate of the distance to Leo T of 409 $^{+29}_{-27}$ kpc (distance modulus of 23.06 $\\pm$ 0.15 mag) was derived from the galaxy's RR Lyrae star. Our V, V-I color-magnitude diagram of Leo T reaches V~29 mag and shows features typical of a galaxy in transition between dwarf irregular and dwarf spheroidal types. A quantitative analysis of the star formation history, based on the comparison of the observed V,V-I CMD...

  19. Petróleo y cambio social como programa de investigación en Venezuela

    Directory of Open Access Journals (Sweden)

    Luis J. González Oquendo

    2006-01-01

    Full Text Available Alo largo del siglo xx, el petróleo ha sido el elemento estructural que ha explicado la estructuración de la sociedad venezolana. Es una idea extendida que Venezuela es lo que la actividad petrolera le ha permitido ser. El presente trabajo se está interesado en estudiar cómo la construcción de la sociedad venezolana ha sido posible desde la óptica de productos intelectuales científico sociales. No interesa sólo una lectura teórica sino hacer una aproximación epistemológica que determine la existencia de un programa de investigación. Se utilizó el modelo VIE de José Padrón para analizar la obra de cinco científicos sociales clave que han estudiado el impacto social del petróleo en Venezuela: Rodolfo Quintero, Carmen Vallarino de Bracho, Roberto Briceño León, María Sol Pérez Schael y Fernando Coronil. Finalmente, se pudo demostrar que el único elemento en común entre estos estudios de investigación es el objeto, aunque cada uno de ellos tiene diferentes construcciones teóricas acerca de éste. De este modo, «petróleo y cambio social en Venezuela» no es todavía un programa de investigación

  20. The low-mass classic Algol-type binary UU Leo revisited

    Science.gov (United States)

    Yang, Yuan-Gui

    2013-12-01

    New multi-color photometry of the eclipsing binary UU Leo, acquired from 2010 to 2013, was carried out by using the 60-cm and 85-cm telescopes at the Xinglong station, which is administered by National Astronomical Observatories, Chinese Academy of Sciences. With the updated Wilson-Devinney code, the photometric solution was derived from BVR light curves. The results imply that UU Leo is a semi-detached Algol-type binary, with a mass ratio of q = 0.100(±0.002). The change in orbital period was reanalyzed based on all available eclipsing times. The O - C curve could be described by an upward parabola superimposed on a quasi-sinusoidal curve. The period and semi-amplitudes are Pmod = 54.5(±1.1) yr and A = 0.0273d(±0.0015d), which may be attributed to the light-time effect via the presence of an invisible third body. The long-term period increases at a rate of dP/dt = +4.64(±0.14) × 10-7d yr-1, which may be interpreted by the conserved mass being transferred from the secondary to the primary. With mass being transferred, the low-mass Algol-type binary UU Leo may evolve into a binary system with a main sequence star and a helium white dwarf.

  1. Leo A: A Late-Blooming Survivor of the Epoch of Reionization in the Local Group

    CERN Document Server

    Cole, A A; Tolstoy, E; III, J S G; Aparicio, A; Dolphin, A E; Gallart, C; Hidalgo, S L; Saha, A; Stetson, P B; Weisz, D R

    2007-01-01

    As part of a major program to use isolated Local Group dwarf galaxies as near-field probes of cosmology, we have obtained deep images of the dwarf irregular galaxy Leo A with the Advanced Camera for Surveys aboard the Hubble Space Telescope. From these images we have constructed a color-magnitude diagram (CMD) reaching apparent [absolute] magnitudes of (M475, M814) > (29.0 [+4.4], 27.9 [+3.4]), the deepest ever achieved for any irregular galaxy beyond the Magellanic Clouds. We derive the star-formation rate (SFR) as a function of time over the entire history of the galaxy. We find that over 90% of all the star formation that ever occurred in Leo A happened more recently than 8 Gyr ago. The CMD shows only a very small amount of star formation in the first few billion years after the Big Bang; a possible burst at the oldest ages cannot be claimed with high confidence. The peak SFR occurred ~1.5-4 Gyr ago, at a level 5-10 times the current value. Our modelling indicates that Leo A has experienced very little met...

  2. The X-ray Behavior of Two CVs TT Ari and DP Leo

    CERN Document Server

    Robinson, C R; Robinson, Craig R.; Cordova, France A.

    1993-01-01

    We present ROSAT PSPC observations of the nova-like, or intermediate polar, TT Ari and the eclipsing polar DP Leo. Observations of TT Ari were performed as part of a simultaneous multiwavelength campaign. The X-ray spectrum of TT Ari from ROSAT was combined with Ginga observations to suggest the presence of three distinct emission components: an optically thin plasma, a dominating bremsstrahlung continuum and one or more iron emission lines. Simultaneous and later IUE observations show modulation in the absorption component of the P Cygni-like CIV line on the spectroscopic period indicating a complex wind structure. Three eclipses were observed from the DP Leo system with intensity dips, not previously observed, occurring prior to each eclipse. The dips are interpreted as the eclipse of the main emission region by an accretion stream varying in impact position or stream shape with time. The DP Leo spectrum is well fit by either a 25 eV blackbody or a soft power law. No evidence exists for accretion onto the s...

  3. Ileostomia continente com preservação da papila íleo-cecal

    Directory of Open Access Journals (Sweden)

    FORMIGA GJS

    2000-01-01

    Full Text Available Seis doentes foram submetidos a ileostomia continente com preservação da papila íleo-cecal, como tempo cirúrgico complementar à proctocolectomia e à colectomia totais, para tratamento de doença inflamatória intestinal e polipose adenomatosa familiar, associada a pólipo degenerado no reto inferior. A técnica utilizada de ileostomia continente preserva a papila íleo-cecal e uma pequena borda circular de parede cecal exteriorizados na parede abdominal. O débito ileal, na primeira semana pós-operatória, não ultrapassou 430 ml/dia, não houve complicações do procedimento e o aspecto estético ficou excelente. Conclui-se que a ileostomia continente com preservação da papila íleo-cecal, definitiva ou temporária, é um procedimento cirúrgico eficiente, em casos selecionados, quando se deseja manter um controle eficaz do efluente intestinal.

  4. Optimal planning of LEO active debris removal based on hybrid optimal control theory

    Science.gov (United States)

    Yu, Jing; Chen, Xiao-qian; Chen, Li-hu

    2015-06-01

    The mission planning of Low Earth Orbit (LEO) active debris removal problem is studied in this paper. Specifically, the Servicing Spacecraft (SSc) and several debris exist on near-circular near-coplanar LEOs. The SSc should repeatedly rendezvous with the debris, and de-orbit them until all debris are removed. Considering the long-duration effect of J2 perturbation, a linear dynamics model is used for each rendezvous. The purpose of this paper is to find the optimal service sequence and rendezvous path with minimum total rendezvous cost (Δv) for the whole mission, and some complex constraints (communication time window constraint, terminal state constraint, and time distribution constraint) should be satisfied meanwhile. Considering this mission as a hybrid optimal control problem, a mathematical model is proposed, as well as the solution method. The proposed approach is demonstrated by a typical active debris removal problem. Numerical experiments show that (1) the model and solution method proposed in this paper can effectively address the planning problem of LEO debris removal; (2) the communication time window constraint and the J2 perturbation have considerable influences on the optimization results; and (3) under the same configuration, some suboptimal sequences are equivalent to the optimal one since their difference in Δv cost is very small.

  5. PRODUÇÃO DE PETRÓLEO E IMPACTOS AMBIENTAIS: ALGUMAS CONSIDERAÇÕES

    Directory of Open Access Journals (Sweden)

    Silas Sarkiz da Silva Martins

    2015-12-01

    Full Text Available O petróleo está a cada dia sendo mais explorado e tem sido um recurso energético gerador de divisas para a economia de países e nações, a exemplo do Brasil, mas, também, difusor de impactos ambientais negativos. As etapas que envolvem a produção de petróleo desde a perfuração de poços até o refino, direta ou indiretamente, têm causado alterações ao meio ambiente. O objetivo deste estudo foi o de compreender os principais impactos ambientais gerados pelas etapas de produção de petróleo, considerando estudos de impacto ambiental (EIAs e seus respectivos relatórios de impacto ambiental (RIMAs. A avaliação dos impactos ambientais se dá através do diagnóstico ambiental da área de influência do empreendimento, o qual é feito para se conhecer os componentes dos meios físico, biológico e socioeconômico da área e, posteriormente, avaliar os efeitos das atividades do empreendimento sobre os mesmos. Pela complexidade da composição química do petróleo, o risco quanto as suas atividades e seu manuseio é, na maioria dos casos, de grande potencial, pois pode haver acidentes, que, por sua vez, podem interferir negativamente no meio ambiente. Ao término do estudo, concluiu-se que a fase de produção de petróleo apresenta diversos aspectos ambientais, os quais geram impactos. Viu-se que os impactos não são apenas de caráter negativo. E, por fim, sugere-se a aplicação de medidas mitigadoras e de um sistema de gestão ambiental eficaz para a minimização e/ou eliminação de tais impactos.

  6. A novel signal processing approach for LEO space debris based on a fence-type space surveillance radar system

    Science.gov (United States)

    Huang, Jian; Hu, Weidong; Ghogho, Mounir; Xin, Qin; Du, Xiaoyong; Guo, Weiwei

    2012-12-01

    The increase in space debris can seriously threaten regular activities in the Low Earth Orbit (LEO) environment. Therefore, it is necessary to develop robust, efficient and reliable techniques to understand the potential motions of the LEO debris. In this paper, we propose a novel signal processing approach to detect and estimate the motions of LEO space debris that is based on a fence-type space surveillance radar system. Because of the sparse distribution of the orbiting debris through the fence in our observations, we formulate the signal detection and the motion parameter estimation as a sparse signal reconstruction problem with respect to an over-complete dictionary. Moreover, we propose a new scheme to reduce the size of the original over-complete dictionary without the loss of the important information. This new scheme is based on a careful analysis of the relations between the acceleration and the directions of arrival for the corresponding LEO space debris. Our simulation results show that the proposed approach can achieve extremely good performance in terms of the accuracy for detection and estimation. Furthermore, our simulation results demonstrate the robustness of the approach in scenarios with a low Signal-to-Noise Ratio (SNR) and the super-resolution properties. We hope our signal processing approach can stimulate further work on monitoring LEO space debris.

  7. John the Grammarian and Leo the Mathematician as a Target of Orthodox Critics: Parallels and Historical Context

    Directory of Open Access Journals (Sweden)

    Tatyana A. Senina (nun Kassia

    2016-11-01

    Full Text Available John the Grammarian and Leo the Mathematician and Philosopher, Byzantine intellectuals of the 9th century who played a major role in the revival of interest in the learning of classical culture in Byzantium, were attacked for their passion for the ancient culture and philosophy, particularly Platonism. Strictly Orthodox opponents accused them of impiety, sorcery and even the worship of pagan gods. Despite the absurdity of such accusations, they show that the orthodox fundamentalists denounced a manifest interest in “human wisdom”, because they considered it as a danger for the “wisdom inspired by God”. Patriarch Methodius of Constantinople accused John the Grammarian both of iconoclastic heresy and of passion for Hellenic writings. Constantine the Sicilian, a disciple of Leo the Philosopher, left his teacher and passed to the circle of admirers of the Patriarch Photios of Constantinople. After Leo’s death Constantin blamed him for his apostasy and excessive devotion to the culture of ancient Greece. 40 years later, Leo Choirosphaktes, a disciple of Leo the Philosopher, was attacked by Arethas, Archbishop of Caesarea, with similar accusations. These cases indicate the presence of various trends among the Byzantine intellectuals of 9th century: one traditionally orthodox, personified by Patriarch Photius, and another more Hellenistic, headed by Leo the Philosopher.

  8. Avaliação de óleo essencial de Eucalyptus urograndis(Myrtaceae no controle de Pentatomidae

    Directory of Open Access Journals (Sweden)

    Taciany Ferreira de Souza

    Full Text Available O objetivo dessa pesquisa foi avaliar o potencial inseticida do óleo essencial de Eucalyptus urograndis para o controle de ninfas e adultos de Euschistus heros (Fabricius, 1794 em bioensaios de laboratório. Foram avaliados quatro parâmetros em ninfas e adultos dessa espécie: exposição por aplicação tópica, exposição em superfície de contato, fagoinibição sem chance de escolha e fagoinibição com dupla chance de escolha. A avaliação, observando-se o número de indivíduos vivos e mortos, foi feita no período de 24 e 48 horas. Constatou-se que óleo essencial de E. urograndis é tóxico para ninfas e adultos de E. heros. Tanto as Doses Letais (DL como as Concentrações Letais (CL determinadas para o óleo diminuíram à medida que aumentou o tempo de exposição dos insetos e a dose aplicada do óleo essencial, indicando uma dependência com o tempo de exposição. Verificou-se que as sementes tratadas com óleo essencial provocaram ação fagoinibidora reduzindo os pontos de alimentação, mostrando-se promissor para o controle alternativo desse inseto.

  9. ALFALFA Discovery of the Nearby Gas-Rich Dwarf Galaxy Leo P. IV. Distance Measurement from LBT Optical Imaging

    CERN Document Server

    McQuinn, Kristen B W; Berg, Danielle; Cannon, John M; Salzer, John J; Adams, Elizabeth A K; Dolphin, Andrew; Giovanelli, Riccardo; Haynes, Martha P; Rhode, Katherine L

    2013-01-01

    Leo P is a low-luminosity dwarf galaxy discovered through the blind HI Arecibo Legacy Fast ALFA (ALFALFA) survey. The HI and follow-up optical observations have shown that Leo P is a gas-rich dwarf galaxy with both active star formation and an underlying older population, as well as an extremely low oxygen abundance. Here, we measure the distance to Leo P by applying the tip of the red giant branch (TRGB) distance method to photometry of the resolved stellar population from new Large Binocular Telescope (LBT) V and I band imaging. We measure a distance modulus of 26.19 (+0.17/-0.50) mag corresponding to a distance of 1.72 (+0.14/-0.40) Mpc. Although our photometry reaches 3 magnitudes below the TRGB, the sparseness of the red giant branch (RGB) yields higher uncertainties on the lower limit of the distance. Leo P is outside the Local Group with a distance and velocity consistent with the local Hubble flow. While located in a very low-density environment, Leo P lies within ~0.5 Mpc of a loose association of dw...

  10. Biodegradability of commercial and weathered diesel oils Biodegradabilidade de óleos diesel comercial e intemperizado

    Directory of Open Access Journals (Sweden)

    Adriano Pinto Mariano

    2008-03-01

    Full Text Available This work aimed to evaluate the capability of different microorganisms to degrade commercial diesel oil in comparison to a weathered diesel oil collected from the groundwater at a petrol station. Two microbiological methods were used for the biodegradability assessment: the technique based on the redox indicator 2,6 - dichlorophenol indophenol (DCPIP and soil respirometric experiments using biometer flasks. In the former we tested the bacterial cultures Staphylococcus hominis, Kocuria palustris, Pseudomonas aeruginosa LBI, Ochrobactrum anthropi and Bacillus cereus, a commercial inoculum, consortia obtained from soil and groundwater contaminated with hydrocarbons and a consortium from an uncontaminated area. In the respirometric experiments it was evaluated the capability of the native microorganisms present in the soil from a petrol station to biodegrade the diesel oils. The redox indicator experiments showed that only the consortia, even that from an uncontaminated area, were able to biodegrade the weathered diesel. In 48 days, the removal of the total petroleum hydrocarbons (TPH in the respirometric experiments was approximately 2.5 times greater when the commercial diesel oil was used. This difference was caused by the consumption of labile hydrocarbons, present in greater quantities in the commercial diesel oil, as demonstrated by gas chromatographic analyses. Thus, results indicate that biodegradability studies that do not consider the weathering effect of the pollutants may over estimate biodegradation rates and when the bioaugmentation is necessary, the best strategy would be that one based on injection of consortia, because even cultures with recognised capability of biodegrading hydrocarbons may fail when applied isolated.Este trabalho objetivou avaliar a capacidade de diferentes microrganismos em degradar óleo diesel comercial em comparação com um óleo diesel intemperizado coletado da água subterrânea em um posto de combust

  11. Atividade insetistática de óleo essencial de Pothomorphe umbellata sobre Sitophilus zeamais

    Directory of Open Access Journals (Sweden)

    Carolina F. Pauliquevis

    2015-12-01

    Full Text Available RESUMO Sitophilus zeamais (Motschulsky, 1885 (Coleoptera: Curculionidae é um dos principais insetos que atacam e comprometem severamente a qualidade de grãos armazenados cujo controle é feito através de inseticidas químicos que nem sempre são eficazes, ocasionam a seleção de insetos resistentes, eliminam populações de inimigos naturais, deixam resíduos nos alimentos e contaminam o meio ambiente. Na tentativa de minimizar o problema com a possibilidade de uma alternativa agroecológica, pesquisas com óleos essenciais têm-se mostrado promissoras. Neste contexto, o objetivo da pesquisa foi identificar o potencial insetistático do óleo essencial da pariparoba no controle do gorgulho-do-milho para o que foram realizados bioensaios para verificar o efeito fumigante, exposição em superfície de contato e repelência. Houve efeito fumigante, os valores da CL50 e CL99 para as 24 h de confinamento dos insetos foram, respectivamente, 0,95 e 6,73 µL g-1. Os valores da CL50 e CL99 para as 24 h de exposição em superfície de contato foram, respectivamente, 0,34 e 4,91 µL cm-2; a repelência ocorreu na primeira hora; desta forma, o óleo essencial de Pothomorphe umbellata apresenta efeito insetistático para o controle de S. zeamais.

  12. Satellite co-locations as a link between SLR, GPS and Low Earth Orbiting (LEO) satellites

    Science.gov (United States)

    Melachroinos, S. A.; Lemoine, F. G.; Chinn, D. S.; Nicolas, J. B.; Zelensky, N. P.; Wimert, J.; Radway, Y.

    2013-12-01

    The procedure applied for the determination of the International Terrestrial Reference Frame (ITRF) requires the combination of all four major techniques of Space Geodesy. This combination is only possibly realized by the introduction of the local-ties between co-located techniques. A local-tie is the lever arm vector between the marker points on the sites where two or more space geodesy instruments operate. The local ties are used as additional observations with proper variances. They are usually derived from local surveys using either classical geodesy or the global navigation satellite systems (GNSS). The Global Positioning System (GPS) plays a major role in the ITRF combination by linking together all the other three techniques SLR, DORIS and VLBI (Altamimi and Collilieux 2009). However, discrepancies between local ties and space geodesy estimates are well known although the reasons for these discrepancies are often not clear. These discrepancies could be either due to errors in local ties and in coordinate estimates or in both. In this study, we use the tracking to G05-35 and G06-36 and one LEO by SLR sites and their combined orbits, earth rotation parameters (ERPs) and station positions in order to establish space-based co-location ties on the stations. The LEO satellite used in this experiment is Jason-2, which carries both GPS and SLR. Therefore from the data-processing point of view the LEO satellite is used as a fast moving station (Thaller et al. 2011). Jason-2 is also equipped with DORIS, but it will be included into another combined analysis. Subsequently, we compare the consistency of our space-based co-locations to the ones from ITRF08 and SLRF08 - IGb08 solutions.

  13. CONSISTÊNCIA DE MISTURA DE GORDURAS HIDROGENADAS E ÓLEO DE SOJA

    Directory of Open Access Journals (Sweden)

    SIMÕES Ilka Sumiyoshi

    1998-01-01

    Full Text Available A consistência é um aspecto funcional importante das gorduras plásticas, que são misturas de cristais de gordura sólida e óleo líquido. A relação entre as duas fases e o caracter cristalino da fase sólida determinam a consistência e a firmeza das amostras. O objetivo do trabalho foi determinar a consistência de duas gorduras vegetais hidrogenadas e suas misturas binárias e ternárias, com a presença ou não de óleo de soja, a partir dos resultados do analisador de textura (TA XT2, variando as profundidades de penetração e o ângulo dos cones. Aplicou-se um modelo de regressão múltipla, do tipo cúbico especial para as misturas de óleo e gorduras, utilizando o aplicativo MIXPLOT para a construção de diagrama triangular. A força de compressão variou de 0,0080 a 5,459 kg, dependendo da amostra e da profundidade de penetração do cone. Para os cones de ângulos 30, 40 e 45º, as consistências foram todas estatisticamente semelhantes, a p< 0,05. Para algumas amostras, os resultados empregando o cone de 20º foram estatisticamente diferentes. Tais diferenças de resultados podem ser justificadas pelo fato da geometria do cone de 20º ser diferente, em função do truncamento de sua ponta. A análise do diagrama triangular mostra que o componente óleo de soja não contribuiu estatisticamente para a consistência. Os coeficientes relativos às interações foram sempre negativos, demonstrando efeito antagônico para a consistência, característico das interações eutéticas entre gorduras. Este efeito eutético ocorre devido à incompatibilidade no estado sólido entre os componentes da mistura.

  14. Genius in the shadows a biography of Leo Szilard, the man behind the bomb

    CERN Document Server

    Lanouette, William

    2013-01-01

    Well-known names such as Albert Einstein, Enrico Fermi, J. Robert Oppenheimer, and Edward Teller are usually those that surround the creation of the atom bomb. One name that is rarely mentioned is Leo Szilard, known in scientific circles as "father of the atom bomb." The man who first developed the idea of harnessing energy from nuclear chain reactions, he is curiously buried with barely a trace in the history of this well-known and controversial topic.Born in Hungary and educated in Berlin, he escaped Hitler's Germany in 1933 and that first year developed his concept of nucle

  15. Entre las dictaduras y el petróleo: las migraciones transnacionales de Guinea Ecuatorial

    OpenAIRE

    Aixelà-Cabré, Yolanda

    2012-01-01

    (ES) El objetivo de este artículo es el de presentar una genealogía de las migraciones guineoecuatorianas desde mediados del siglo XX hasta la actualidad. La emigración guineana se inició a finales del período colonial y estuvo motivada por temas políticos y formativos, causas que continuaron vertebrándola tras la instauración de las dictaduras de Macías y de Obiang. Ambas se combinaron con las minoritarias migraciones laborales. El hallazgo de petróleo a mediados de la década ...

  16. Reservsõjaväelasele Leo Kunnasele anti Stalkeri romaaniauhind / Kalev Kask, Kaarel Kressa

    Index Scriptorium Estoniae

    Kask, Kalev

    2009-01-01

    Eesti Ulmeühingu Stalkeri-nimelised auhinnad jaotusid järgmiselt: algupärase romaani auhind - Leo Kunnas (romaani "Gort Ashryn" 1. osa "Enne viimast sõda"), algupärase jutu auhind - Indrek Hargla ("Minu päevad Liinaga", ilm. Looming, 2008, nr. 8), algupärase lühijutu auhind - Laur Kraft ("Ultima Cthule", ilm. võrguajakirjas Algernon), tõlkeromaani auhind - Sergei Lukjanenko ("Öine Vahtkond"), kogumiku auhind - Poul Anderson ("Taevarahvas"), tõlkejutu auhind - Paolo Bacigalup ("Flööditüdruk")

  17. Bioremediación de suelos contaminados con hidrocarburos derivados del petróleo

    OpenAIRE

    2006-01-01

    El manejo inadecuado de los materiales y residuos peligrosos ha generado a escala mundial, un problema de contaminación de suelos, aire y agua. Entre las más severas contaminaciones se destacan las que se produjeron y todavía se producen a causa de la extracción y el manejo del petróleo en todos los países productores de hidrocarburos. En nuestro país, el transporte de crudo y sus derivados se ha visto afectado considerablemente durante los últimos 18 años, por una permanente actividad terror...

  18. Measurements of Multi-star Systems LEO 5 and MKT 13

    Science.gov (United States)

    AlZaben, Faisal; Priest, Allen; Priest, Stephen; Qiu, Rex; Boyce, Grady; Boyce, Pat

    2016-04-01

    We report measurements of the position angles and separations of two multi-star systems observed during the fall of 2015. Image data was obtained using an online 17-inch iTelescope system in Nerpio, Spain. Image data was analyzed using Maxim DL Pro 6 and Mira Pro x64 software tools at the Army and Navy Academy in Carlsbad, California. Our measurements of the LEO 5 system are consistent with historical data, although inconclusive as to the nature of the system. Our measurements and the historical data for the MKT 13 system show a consistent linearity in the position angle and separation.

  19. Íleo biliar y fístula colecistoduodenal. Informe de un caso

    OpenAIRE

    Carlos Salazar-Lozano; Erick Rolando Rocha-Guevara; Alberto Vargas-Gismondi; Mauricio de la Fuente-Lira; Rodrigo Ernesto de Obaldía-Zeledón; Carlos Cordero-Vargas

    2006-01-01

    Objetivo: describir un caso de íleo biliar y fístula colecistoduodenal, atendido en el Hospital de Especialidades, Centro Médico Nacional Siglo XXI, IMSS. Caso clínico: hombre de 54 años de edad con diagnóstico de colecistitis aguda, sometido a apendicectomía a los 34 años. Sin historia de enfermedad biliar. Al examen físico se encontraba afebril, abdomen con distensión leve, dolor a la palpación en hipocondrio derecho y Murphy positivo. Los exámenes de laboratorio indicaron leucocitos de 8,9...

  20. PRIMA Platform capability for satellite missions in LEO and MEO (SAR, Optical, GNSS, TLC, etc.)

    Science.gov (United States)

    Logue, T.; L'Abbate, M.

    2016-12-01

    PRIMA (Piattaforma Riconfigurabile Italiana Multi Applicativa) is a multi-mission 3-axis stabilized Platform developed by Thales Alenia Space Italia under ASI contract.PRIMA is designed to operate for a wide variety of applications from LEO, MEO up to GEO and for different classes of satellites Platform Family. It has an extensive heritage in flight heritage (LEO and MEO Satellites already fully operational) in which it has successfully demonstrated the flexibility of use, low management costs and the ability to adapt to changing operational conditions.The flexibility and modularity of PRIMA provides unique capability to satisfy different Payload design and mission requirements, thanks to the utilization of recurrent adaptable modules (Service Module-SVM, Propulsion Module-PPM, Payload Module-PLM) to obtain mission dependent configuration. PRIMA product line development is continuously progressing, and is based on state of art technology, modular architecture and an Integrated Avionics. The aim is to maintain and extent multi-mission capabilities to operate in different environments (LEO to GEO) with different payloads (SAR, Optical, GNSS, TLC, etc.). The design is compatible with a wide range of European and US equipment suppliers, thus maximising cooperation opportunity. Evolution activities are mainly focused on the following areas: Structure: to enable Spacecraft configurations for multiple launch; Thermal Control: to guarantee thermal limits for new missions, more demanding in terms of environment and payload; Electrical: to cope with higher power demand (e.g. electrical propulsion, wide range of payloads, etc.) considering orbital environment (e.g. lighting condition); Avionics : AOCS solutions optimized on mission (LEO observation driven by agility and pointing, agility not a driver for GEO). Use of sensors and actuators tailored for specific mission and related environments. Optimised Propulsion control. Data Handling, SW and FDIR mission customization

  1. Óleos essenciais: aspectos gerais e usos em terapias naturais

    OpenAIRE

    Murbach Teles Machado, Bruna Fernanda; Fernandes Junior,Ary

    2011-01-01

    O conhecimento tradicional atualmente é uma fonte para pesquisas na busca por novos compostos biologicamente ativos e como terapêutica efetiva que contemple os cuidados atuais para a saúde. Políticas de saúde utilizando estas fontes têm sido incentivadas por organizações internacionais e nacionais, como a Organização Mundial da Saúde e o Ministério da Saúde do Brasil. A Aromaterapia e os óleos essenciais são uma destas vertentes que estão em ascensão comercial e como objeto de estudo. O prese...

  2. Acción antimicrobiana de extracto etanólico de propóleos sobre estreptococos mutans

    Directory of Open Access Journals (Sweden)

    Patricia Alejandra Vaculik

    2014-12-01

    Full Text Available El propóleo es un producto natural, posee una amplia variedad de propiedades vinculadas a las ciencias de la salud. De acuerdo al lugar de origen, condiciones climatológicas y tipo de especies botánicas circundantes, son las características que va a reunir. Por ello la particularidad de conocer el tipo de propóleos de nuestra zona geográfica y las propiedades que posee de acuerdo a sus compuestos químicos. La caries dental es una enfermedad infecciosa, que se origina por la interacción de múltiples factores, la dieta, el diente susceptible, los microorganismos, tiempo y la edad. Entre los microorganismos implicados en la formación de caries encontramos al Estreptococos mutans. El objetivo de este trabajo es conocer el propóleo de nuestra región y sus efectos antimicrobianos sobre los Estreptococos mutans.

  3. LEO星座网络动态源路由算法%Dynamic Source Routing Algorithm for LEO Satellite Networks

    Institute of Scientific and Technical Information of China (English)

    万鹏; 曹志刚; 王京林

    2007-01-01

    近年来,在低轨(LEO)卫星星座通信网络中采用网际协议(IP)路由算法的研究已经取得了一系列进展,文章论述了LEO星座通信网络的特点、拓扑结构和虚拟节点策略.在此基础上提出了基于泛洪路由的LEO星座动态源路由算法DSR-LSN(Dynamic Source Routing algorithm in LEO Satellite Networks),星座网络仿真表明,DSR-LSN算法具有网络路由状态稳定性好、时延小的优点.

  4. Caracterização e atividade antibacteriana de óleos essenciais de plantas condimentares e medicinais contra Staphylococcus aureus e Escherichia coli

    Directory of Open Access Journals (Sweden)

    A.F. Millezi

    2013-01-01

    Full Text Available Os óleos essenciais são metabólitos secundários vegetais com propriedades biológicas diferenciadas, dentre elas a atividade contra microrganismos, sendo de importante interesse para a indústria de alimentos. As concentrações mínimas inibitórias (CMI desses óleos para diversas bactérias devem ser determinadas. As CMI variam de acordo com o óleo utilizado, dos compostos majoritários e do tipo de bactéria. Nesta pesquisa, os óleos essenciais das plantas Satureja montana L., Cymbopogon nardus L. e Citrus limonia Osbeck foram caracterizados quimicamente e determinada a CMI sobre as bactérias Staphylococcus aureus ATCC 2592 e Escherichia coli ATCC 25922. A CMI para todos os óleos contra E. coli foi 1,5%, já S. aureus foi sensível a partir da concentração de 5,0% do óleo essencial de S. montana e 1,5% foi a CMI obtida quando utilizados os óleos essenciais das outras espécies estudadas. Na constituição química os componentes majoritários para os óleos de S. montana, C. narduse C. limonia Osbeck foram respectivamente o timol, citronelal e limoneno.

  5. Factores de riesgo asociados a íleo posquirúrgico prolongado en pacientes sometidos a resección electiva de colon

    Directory of Open Access Journals (Sweden)

    M.A. Juárez-Parra

    2015-10-01

    Conclusiones: La presencia de estos factores de riesgo pueden servir como alertas para un seguimiento más cercano en pacientes de alto riesgo de íleo postoperatorio. El uso de anestesia peridural pudiera disminuir la incidencia de íleo.

  6. Commentary: Science, Technology, and Society in Guidelines for Using Technology to Prepare Social Studies Teachers--A Reply to Hicks et al. and Crocco and Leo

    Science.gov (United States)

    Mason, Lance

    2015-01-01

    This essay is a response to both the "Guidelines for Using Technology to Prepare Social Studies Teachers" published in this journal by Hicks, Lee, Berson, Bolick, and Diem (2014) and the rejoinder by Crocco and Leo (2015). The author agrees with Crocco and Leo's assessment that removing the principal regarding science, technology, and…

  7. THE SPACE MOTION OF LEO I: THE MASS OF THE MILKY WAY'S DARK MATTER HALO

    Energy Technology Data Exchange (ETDEWEB)

    Boylan-Kolchin, Michael; Bullock, James S. [Center for Cosmology, Department of Physics and Astronomy, University of California, 4129 Reines Hall, Irvine, CA 92697 (United States); Sohn, Sangmo Tony; Van der Marel, Roeland P. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Besla, Gurtina, E-mail: m.bk@uci.edu [Department of Astronomy, Columbia University, New York, NY 10027 (United States)

    2013-05-10

    We combine our Hubble Space Telescope measurement of the proper motion of the Leo I dwarf spheroidal galaxy (presented in a companion paper) with the highest resolution numerical simulations of Galaxy-size dark matter halos in existence to constrain the mass of the Milky Way's dark matter halo (M{sub vir,MW}). Despite Leo I's large Galactocentric space velocity (200 km s{sup -1}) and distance (261 kpc), we show that it is extremely unlikely to be unbound if Galactic satellites are associated with dark matter substructure, as 99.9% of subhalos in the simulations are bound to their host. The observed position and velocity of Leo I strongly disfavor a low-mass Milky Way: if we assume that Leo I is the least bound of the Milky Way's classical satellites, then we find that M{sub vir,MW} > 10{sup 12} M{sub Sun} at 95% confidence for a variety of Bayesian priors on M{sub vir,MW}. In lower mass halos, it is vanishingly rare to find subhalos at 261 kpc moving as fast as Leo I. Should an additional classical satellite be found to be less bound than Leo I, this lower limit on M{sub vir,MW} would increase by 30%. Imposing a mass-weighted {Lambda}CDM prior, we find a median Milky Way virial mass of M{sub vir,MW} = 1.6 Multiplication-Sign 10{sup 12} M{sub Sun }, with a 90% confidence interval of [1.0-2.4] Multiplication-Sign 10{sup 12} M{sub Sun }. We also confirm a strong correlation between subhalo infall time and orbital energy in the simulations and show that proper motions can aid significantly in interpreting the infall times and orbital histories of satellites.

  8. Avaliação da atividade larvicida do óleo essencial do Zingiber officinale Roscoe (gengibre frente ao mosquito Aedes aegypti

    Directory of Open Access Journals (Sweden)

    P.R.B. GOMES

    Full Text Available RESUMO Este trabalho analisa o efeito larvicida do óleo Zingiber officinale Roscoe contra larvas em terceiro estágio do mosquito Aedes aegypti. Extraiu-se quantitativamente o óleo essencial por hidrodestilação e calculou-se a CL50 do óleo, a partir dos métodos de Reed-Muench e Pizzi, respectivamente. O óleo essencial obteve CL50 de 76,07 (±2,24 μg mL-1 e rendimento de 0,52% m/v. Os resultados indicam que o óleo essencial avaliado é composto por substâncias que propiciam efeito larvicida contra Aedes aegypti.

  9. Improved photometry of SDSS crowded field images: Structure and dark matter content in the dwarf spheroidal galaxy Leo I

    CERN Document Server

    Smolcic, V; Bell, E F; Coleman, M G; Rix, H W; Schinnerer, E; Ivezic, Z; Kniazev, A

    2007-01-01

    We explore how well crowded field point-source photometry can be accomplished with SDSS data: We present a photometric pipeline based on DoPhot, and tuned for analyzing crowded-field images from the SDSS. Using Monte Carlo simulations we show that the completeness of source extraction is above 80% to i >6 ( Ic_sol), and possibly >75 if the DM halo dominates the mass and extends further out than 12'. In summary, our results show that Leo I is a symmetric, relaxed and bound system; this supports the idea that Leo I is a dark-matter dominated system.

  10. Efeito do dibenzotiofeno - DBT (derivado do petróleo) no crescimento e na morfologia de rhizopus arrhizus UCP 402

    OpenAIRE

    Renata Gonçalves dos Santos Inácio

    2009-01-01

    O presente trabalho teve como objetivo investigar o efeito do dibenzotiofeno DBT (derivado do petróleo) no crescimento e na morfologia de Rhizopus arrhizus UCP 402. Com o aumento da utilização de combustíveis fósseis por vários países industrializados, um sério problema ambiental se agrava devido à qualidade das reservas do petróleo, tendo em vista a quantidade de enxofre, e conseqüentemente, maior toxicidade para o meio ambiente. Por sua vez, o dibenzotiofeno (DBT) é um composto organossulf...

  11. Determinações preliminares do teor de óleo essencial em camomila cultivada no Brasil

    OpenAIRE

    Donalisio,Mario Guilherme Roberto

    1985-01-01

    Amostras de capítulos florais, pedúnculos florais e caules de camomila cultivada no Brasil foram destiladas em aparelho destilador de Clevenger para avaliação dos respectivos teores de óleo essencial, sendo encontrados os seguintes valores médios por material destilado: capítulos florais: 0,421%; pedúnculos florais: 0,132% e caules:0,0251 %. Os valores percentuais de óleo essencial relativos a capítulos florais são comparáveis aos encontrados em camomila produzida em diversos países produtore...

  12. Linhaça marrom e dourada: propriedades químicas e funcionais das sementes e dos óleos prensados a frio

    Directory of Open Access Journals (Sweden)

    Ana Karina Mauro Barroso

    2014-01-01

    Full Text Available O objetivo do estudo foi comparar a composição química e a capacidade antioxidante das sementes e dos óleos de linhaça marrom e dourada, e avaliar a estabilidade oxidativa dos óleos. Nas sementes, foram determinados: composição centesimal, capacidade antioxidante total e compostos fenólicos totais. Nos óleos, foram determinados: índice de acidez e peróxido, matéria insaponificável, composição em ácidos graxos, tocoferóis, capacidade antioxidante, compostos fenólicos totais e estabilidade oxidativa em quatro condições de estocagem por até um ano. Não houve diferenças significativas entre os tipos de sementes quanto às variáveis investigadas, e ainda entre os óleos quanto ao rendimento da prensagem, composição em ácidos graxos insaturados, índice de acidez, teores de insaponificáveis e compostos fenólicos totais. Apesar do declínio da estabilidade oxidativa de ambos os óleos durante o armazenamento, o óleo de linhaça marrom e os óleos estocados sob refrigeração apresentaram-se mais estáveis. O índice de peróxido foi maior no óleo de linhaça dourada. O teor de tocoferol total e capacidade antioxidante total foram maiores no óleo de linhaça marrom. Contudo, observou-se uma igualdade entre as sementes de ambas as variedades de linhaça e uma superioridade do óleo de linhaça marrom.

  13. FRACIONAMENTO DE ÓLEOS DE CITROS UTILIZANDO FLUIDOS SUPERCRÍTICOS

    Directory of Open Access Journals (Sweden)

    Marisa MENDES

    1997-12-01

    Full Text Available O objetivo deste trabalho é o estudo sobre o fracionamento do óleo de laranja. Neste sentido, o limoneno e o linalol foram considerados os componentes-chaves do óleo de laranja, representando os terpenos e compostos oxigenados, respectivamente. Para modelar os dados de equilíbrio de fases foi usada a equação de estado de Peng-Robinson, juntamente com as regras de mistura de van der Waals, uni e biparamétrica, e de Panagiotopoulos e Reid. O uso desses modelos termodinâmicos permitiu determinar as condições de temperatura e pressão que levaram aos melhores valores do par seletividade-capacidade.The objective of this work is to study the fractionation of the citrus oils, especially orange oil. The orange oil is considered to be a mixture of two main components, limonene and linalool, which represent the terpenes and oxygenated group fractions, respectively. The Peng-Robinson equation of state using the van der Waals, with one or two parameters, and Panagiotopoulos and Reid mixing rules, were used to correlate and predict the binary and ternary high pressure phase equilibria of CO2 containing systems . The use of thermodynamic models to predict the phase equilibria allowed to establish the conditions of temperature and pressure, which led to the best results of selectivities and capacities of the extraction.

  14. The ACS LCID Project. VIII. The short-period Cepheids of Leo A

    CERN Document Server

    Bernard, Edouard J; Gallart, Carme; Fiorentino, Giuliana; Cassisi, Santi; Aparicio, Antonio; Cole, Andrew A; Drozdovsky, Igor; Hidalgo, Sebastian L; Skillman, Evan D; Stetson, Peter B; Tolstoy, Eline

    2013-01-01

    We present the results of a new search for variable stars in the Local Group dwarf galaxy Leo A, based on deep photometry from the Advanced Camera for Surveys onboard the Hubble Space Telescope. We detected 166 bona fide variables in our field, of which about 60 percent are new discoveries, and 33 candidate variables. Of the confirmed variables, we found 156 Cepheids, but only 10 RR Lyrae stars despite nearly 100 percent completeness at the magnitude of the horizontal branch. The RR Lyrae stars include 7 fundamental and 3 first-overtone pulsators, with mean periods of 0.636 and 0.366 day, respectively. From their position on the period-luminosity (PL) diagram and light-curve morphology, we classify 91, 58, and 4 Cepheids as fundamental, first-overtone, and second-overtone mode Classical Cepheids (CC), respectively, and two as population II Cepheids. However, due to the low metallicity of Leo A, about 90 percent of the detected Cepheids have periods shorter than 1.5 days. Comparison with theoretical models ind...

  15. An Investigation on Advantages of Utilizing Adaptive Bit Rate for LEO Satellite Link Engineering

    Directory of Open Access Journals (Sweden)

    Mehdi Hosseini

    2012-09-01

    Full Text Available The paper aims to investigate the advantages of using adaptive bit rate in the communication link of a LEO satellite. While doing the study, it is assumed that there is a communication subsystem on-board responsible for gathering the information sent by a number of ground user terminals. The subsystem which operates based on Store-and-Forward (SAF Scenario, contains two communication links, one for receiving data from user terminals (store case, and the other for forwarding the stored data to an Earth station (forward case. In fact, the current work aims to improve the volume of the data forwarded to Earth station. To this end, the Forward case bit rate is varied adaptively, and then by analyzing the power budget in a practical condition, the improvement achieved is evaluated. The results specifically obtained for a sample LEO satellite shows that utilizing adaptive bit rate instead of fixed bit rate can increase the daily data exchange up to about 100%.

  16. REVISITING THE DOPPLER FILTER OF LEO SATELLITE GNSS RECEIVERS FOR PRECISE VELOCITY ESTIMATION

    Institute of Scientific and Technical Information of China (English)

    Chen Xi; Gao Wenyun; Wan Yunheng

    2013-01-01

    The theoretical aspects of the precise velocity determination of Low Earth Orbit (LEO) satellites' onboard Global Navigation Satellite Systems (GNSS) receivers are derived.It shows that the receiver's Phase Lock Loop (PLL) is required to feature extremely small group delay within its low frequency band,which is in contrast to existing work that proposed wide band linear phase filters.Following this theory,a Finite Impulse Response (FⅠR) filter is proposed.To corroborate,the proposed FIR filter and an Infinite Impulse Response (ⅡR) filter lately proposed in literals are implemented in a LEO satellite onboard GNSS receiver.Tests are conducted using a third party commercial GPS,signal generator.The results show that the GNSS receiver with the proposed FⅠR achieves 11 mm/s R.M.S precision,while the GNSS receiver with the ⅡR filter has a filter-caused velocity error that can not be ignored for space borne GNSS receivers.

  17. Minimum Number of Observation Points for LEO Satellite Orbit Estimation by OWL Network

    Science.gov (United States)

    Park, Maru; Jo, Jung Hyun; Cho, Sungki; Choi, Jin; Kim, Chun-Hwey; Park, Jang-Hyun; Yim, Hong-Suh; Choi, Young-Jun; Moon, Hong-Kyu; Bae, Young-Ho; Park, Sun-Youp; Kim, Ji-Hye; Roh, Dong-Goo; Jang, Hyun-Jung; Park, Young-Sik; Jeong, Min-Ji

    2015-12-01

    By using the Optical Wide-field Patrol (OWL) network developed by the Korea Astronomy and Space Science Institute (KASI) we generated the right ascension and declination angle data from optical observation of Low Earth Orbit (LEO) satellites. We performed an analysis to verify the optimum number of observations needed per arc for successful estimation of orbit. The currently functioning OWL observatories are located in Daejeon (South Korea), Songino (Mongolia), and Oukaïmeden (Morocco). The Daejeon Observatory is functioning as a test bed. In this study, the observed targets were Gravity Probe B, COSMOS 1455, COSMOS 1726, COSMOS 2428, SEASAT 1, ATV-5, and CryoSat-2 (all in LEO). These satellites were observed from the test bed and the Songino Observatory of the OWL network during 21 nights in 2014 and 2015. After we estimated the orbit from systematically selected sets of observation points (20, 50, 100, and 150) for each pass, we compared the difference between the orbit estimates for each case, and the Two Line Element set (TLE) from the Joint Space Operation Center (JSpOC). Then, we determined the average of the difference and selected the optimal observation points by comparing the average values.

  18. Real-Time Optical Surveillance of LEO/MEO with Small Telescopes

    Science.gov (United States)

    Zimmer, P.; McGraw, J.; Ackermann, M.

    J.T. McGraw and Associates, LLC operates two proof-of-concept wide-field imaging systems to test novel techniques for uncued surveillance of LEO/MEO/GEO and, in collaboration with the University of New Mexico (UNM), uses a third small telescope for rapidly queued same-orbit follow-up observations. Using our GPU-accelerated detection scheme, the proof-of-concept systems operating at sites near and within Albuquerque, NM, have detected objects fainter than V=13 at greater than 6 sigma significance. This detection approximately corresponds to a 16 cm object with albedo of 0.12 at 1000 km altitude. Dozens of objects are measured during each operational twilight period, many of which have no corresponding catalog object. The two proof-of-concept systems, separated by ~30km, work together by taking simultaneous images of the same orbital volume to constrain the orbits of detected objects using parallax measurements. These detections are followed-up by imaging photometric observations taken at UNM to confirm and further constrain the initial orbit determination and independently assess the objects and verify the quality of the derived orbits. This work continues to demonstrate that scalable optical systems designed for real-time detection of fast moving objects, which can be then handed off to other instruments capable of tracking and characterizing them, can provide valuable real-time surveillance data at LEO and beyond, which substantively informs the SSA process.

  19. A LEO-Based Solar-Shade System to Mitigate Global Warming

    CERN Document Server

    Suresh, Rahul

    2015-01-01

    The development of a Low-Earth-Orbit (LEO) based solar-shade system, as part of a technically- and financially-viable multipurpose system to provide long-term solutions to global warming and the energy crisis is discussed. The proposed solar-shade and power system would be enabled by the development of a previously-proposed less-expensive, environment-friendly, space-elevator system to lift mass into space. The solar shades, even during their early deployment and growth in LEO, would provide benefits such as reduction of space-debris and depletion of the Van Allen radiation belts.The Terrestrial temperature profile has been approximated for each latitudinal zone with a one-dimensional model. A shade ring at an altitude of 2000-4000 km, consisting of thin-film mega panels totaling up to 4% of the earths surface area (to block ~1% of insolation), is proposed. The effects of such near-polar rings on the global temperature pattern has been examined using the simple model. Specific emphasis has been laid on this e...

  20. Data analysis and interpretation related to space system/environment interactions at LEO altitude

    Science.gov (United States)

    Raitt, W. John; Schunk, Robert W.

    1991-01-01

    Several studies made on the interaction of active systems with the LEO space environment experienced from orbital or suborbital platforms are covered. The issue of high voltage space interaction is covered by theoretical modeling studies of the interaction of charged solar cell arrays with the ionospheric plasma. The theoretical studies were complemented by experimental measurements made in a vacuum chamber. The other active system studied was the emission of effluent from a space platform. In one study the emission of plasma into the LEO environment was studied by using initially a 2-D model, and then extending this model to 3-D to correctly take account of plasma motion parallel to the geomagnetic field. The other effluent studies related to the releases of neutral gas from an orbiting platform. One model which was extended and used determined the density, velocity, and energy of both an effluent gas and the ambient upper atmospheric gases over a large volume around the platform. This model was adapted to study both ambient and contaminant distributions around smaller objects in the orbital frame of reference with scale sizes of 1 m. The other effluent studies related to the interaction of the released neutral gas with the ambient ionospheric plasma. An electrostatic model was used to help understand anomalously high plasma densities measured at times in the vicinity of the space shuttle orbiter.

  1. Detection of ultra-weak magnetic fields in Am stars: beta UMa and theta Leo

    CERN Document Server

    Blazère, A; Lignières, F; Aurière, M; ballot, J; Böhm, T; Folsom, C P; Gaurat, M; Jouve, L; Ariste, A Lopez; Neiner, C; Wade, G A

    2016-01-01

    An extremely weak circularly polarized signature was recently discovered in spectral lines of the chemically peculiar Am star Sirius A. A weak surface magnetic field was proposed to account for the observed polarized signal, but the shape of the phase-averaged signature, dominated by a prominent positive lobe, is not expected in the standard theory of the Zeeman effect. We aim at verifying the presence of weak circularly polarized signatures in two other bright Am stars, beta UMa and theta Leo, and investigating the physical origin of Sirius-like polarized signals further. We present here a set of deep spectropolarimetric observations of beta UMa and theta Leo, observed with the NARVAL spectropolarimeter. We analyzed all spectra with the Least Squares Deconvolution multiline procedure. To improve the signal-to-noise ratio and detect extremely weak signatures in Stokes V profiles, we co-added all available spectra of each star (around 150 observations each time). Finally, we ran several tests to evaluate wheth...

  2. Detection of a Planetary Companion around the giant star \\gam1leo

    CERN Document Server

    Han, Inwoo; Kim, K M; Mkrtichian, D E; Hatzes, A P; Valyavin, G

    2009-01-01

    Aims: Our primary goal is to search for planets around intermediate mass stars. We are also interested in studying the nature of radial velocity (RV) variations of K giant stars. Methods: We selected about 55 early K giant (K0 - K4) stars brighter than fifth magnitude that were observed using BOES, a high resolution spectrograph attached to the 1.8 m telescope at BOAO (Bohyunsan Optical Astronomy Observatory). BOES is equipped with $I_2$ absorption cell for high precision RV measurements. Results: We detected a periodic radial velocity variations in the K0 III star \\gam1leo with a period of P = 429 days. An orbital fit of the observed RVs yields a period of P = 429 days, a semi-amplitude of K = 208 \\mps, and an eccentricity of e = 0.14. To investigate the nature of the RV variations, we analyzed the photometric, CaII $\\lambda$ 8662 equivalent width, and line-bisector variations of \\gam1leo. We conclude that the detected RV variations can be best explained by a planetary companion with an estimated mass of m $...

  3. A Parametric Study on Using Active Debris Removal to Stabilize the Future LEO Debris Environment

    Science.gov (United States)

    Liou, J.C.

    2010-01-01

    Recent analyses of the instability of the orbital debris population in the low Earth orbit (LEO) region and the collision between Iridium 33 and Cosmos 2251 have reignited the interest in using active debris removal (ADR) to remediate the environment. There are; however, monumental technical, resources, operational, legal, and political challenges in making economically viable ADR a reality. Before a consensus on the need for ADR can be reached, a careful analysis of the effectiveness of ADR must be conducted. The goal is to demonstrate the feasibility of using ADR to preserve the future environment and to guide its implementation to maximize the benefit-cost ratio. This paper describes a comprehensive sensitivity study on using ADR to stabilize the future LEO debris environment. The NASA long-term, orbital debris evolutionary model, LEGEND, is used to quantify the effects of many key parameters. These parameters include (1) the starting epoch of ADR implementation, (2) various target selection criteria, (3) the benefits of collision avoidance maneuvers, (4) the consequence of targeting specific inclination or altitude regimes, (5) the consequence of targeting specific classes of vehicles, and (6) the timescale of removal. Additional analyses on the importance of postmission disposal and how future launches might affect the requirements to stabilize the environment are also included.

  4. A Parametric Study on Using Active Debris Removal for LEO Environment Remediation

    Science.gov (United States)

    2010-01-01

    Recent analyses on the instability of the orbital debris population in the low Earth orbit (LEO) region and the collision between Iridium 33 and Cosmos 2251 have reignited the interest in using active debris removal (ADR) to remediate the environment. There are; however, monumental technical, resource, operational, legal, and political challenges in making economically viable ADR a reality. Before a consensus on the need for ADR can be reached, a careful analysis of its effectiveness must be conducted. The goal is to demonstrate the need and feasibility of using ADR to better preserve the future environment and to guide its implementation to maximize the benefit-to-cost ratio. This paper describes a new sensitivity study on using ADR to stabilize the future LEO debris environment. The NASA long-term orbital debris evolutionary model, LEGEND, is used to quantify the effects of several key parameters, including target selection criteria/constraints and the starting epoch of ADR implementation. Additional analyses on potential ADR targets among the currently existing satellites and the benefits of collision avoidance maneuvers are also included.

  5. Large-scale structure and galaxy motions in the Leo/Cancer constellations

    CERN Document Server

    Karachentsev, Igor D; Karachentseva, Valentina E

    2015-01-01

    In the region of the sky limited by the coordinates RA$=7.0^h...12.0^h$, Dec$=0^\\circ...+20^\\circ$ and extending from the Virgo Cluster to the South Pole of the Local Supercluster, we consider the data on the galaxies with radial velocities $V_{LG}\\lesssim 2000$ km/s. For 290 among them, we determine individual distances and peculiar velocities. In this region, known as the local velocity anomaly zone, there are 23 groups and 20 pairs of galaxies for which the estimates of virial/orbital masses are obtained. A nearby group around NGC3379 = Leo I and NGC3627 as well as the Local Group show the motion from the Local Void in the direction of Leo cloud with a characteristic velocity of about 400 km/s. Another rich group of galaxies around NGC3607 reveals peculiar velocity of about -420 km/s in the frame of reference related with the cosmic background radiation. A peculiar scattered association of dwarf galaxies Gemini Flock at a distance of 8 Mpc has the radial velocity dispersion of only 20 km/s and the size of ...

  6. WFPC2 Observations of Leo A A Predominantly Young Galaxy within the Local Group

    CERN Document Server

    Tolstoy, E; Cole, A A; Hössel, J G; Saha, A; Dohm-Palmer, R C; Skillman, E D; Mateo, M; Hurley-Keller, D A; Tolstoy, Eline; Mateo, Mario

    1998-01-01

    The unprecedented detail of the WFPC2 colour-magnitude diagrams of the resolved stellar population of Leo A presented here allows us to determine a new distance and an accurate star formation history for this extremely metal-poor Local Group dwarf irregular galaxy. From the position of the red clump, the helium-burning blue loops and the tip of the red giant branch, we obtain a distance modulus, m-M=24.2+/-0.2, or 690 +/- 60 kpc, which places Leo A firmly within the Local Group. Our interpretation of these features in the WFPC2 CMDs at this new distance based upon extremely low metallicity (Z=0.0004) theoretical stellar evolution models suggests that this galaxy is predominantly young, i.e. <2 Gyr old. A major episode of star formation 900 - 1500 Gyr ago can explain the red clump luminosity and also fits in with our interpretation of the number of anomalous Cepheid variable stars seen in this galaxy. We cannot rule out the presence of an older, underlying globular cluster age stellar population with these ...

  7. UMR: A utility-maximizing routing algorithm for delay-sensitive service in LEO satellite networks

    Directory of Open Access Journals (Sweden)

    Lu Yong

    2015-04-01

    Full Text Available This paper develops a routing algorithm for delay-sensitive packet transmission in a low earth orbit multi-hop satellite network consists of micro-satellites. The micro-satellite low earth orbit (MS-LEO network endures unstable link connection and frequent link congestion due to the uneven user distribution and the link capacity variations. The proposed routing algorithm, referred to as the utility maximizing routing (UMR algorithm, improve the network utility of the MS-LEO network for carrying flows with strict end-to-end delay bound requirement. In UMR, first, a link state parameter is defined to capture the link reliability on continuing to keep the end-to-end delay into constraint; then, on the basis of this parameter, a routing metric is formulated and a routing scheme is designed for balancing the reliability in delay bound guarantee among paths and building a path maximizing the network utility expectation. While the UMR algorithm has many advantages, it may result in a higher blocking rate of new calls. This phenomenon is discussed and a weight factor is introduced into UMR to provide a flexible performance option for network operator. A set of simulations are conducted to verify the good performance of UMR, in terms of balancing the traffic distribution on inter-satellite links, reducing the flow interruption rate, and improving the network utility.

  8. Os efeitos do óleo essencial decitrusaurantiumno tratamento de sobrepeso e obesidade

    Directory of Open Access Journals (Sweden)

    Anna Carolina Faria

    2012-06-01

    Full Text Available Introdução: O objetivo deste estudo foi verificar os possíveis efeitos do óleo essencial de Citrusaurantiumvar. Amara no tratamento de Sobrepeso e obesidade Grau I. Método: Trata-se de um estudo clínico piloto duplo-cego randomizado, de natureza quantitativa, realizado na Clínica de Naturologia da UNISUL com 15 moradores de Palhoça/SC, com idade de 20 a 42 anos. Os participantes foram divididos, pela técnica de amostragem aleatória simples, em dois grupos: experimental (óleo essencial, n=8 e controle (essência, n=7. Os participantes utilizaram creme neutro com 2% de óleo essencial (grupo tratado e com 2% de essência (sem princípios ativos no grupo controle nas regiões abdominal, glúteo, quadril e coxas. Além disso, foi orientado para todos os participantes: caminhada em ritmo moderado com freqüência de 40 minutos, 3 vezes por semana e dieta de 1800 e 2000 calorias diárias, para o sexo feminino e masculino, respectivamente. Neste trabalho foram realizados 4 encontros, um por semana, ao longo de 21 dias para avaliação das variáveis do estudo. Utilizou-se dos testes estatísticos do qui-quadrado de Pearson ou do teste exato de Fisher, para as variáveis categóricas, e do teste t de Student para as variáveis contínuas, considerando estatisticamente significante quando p<0,05. O presente estudo foi aprovado pelo CEP-UNISUL (protocolo 11.260.4.06.III. Resultados: O Grupo Experimental apresentou diferença estatística e clinicamente significante em relação ao grupo controle. Os resultados da pesquisa sugerem que o uso do óleo essencial Citrusaurantiumvar. Amara favoreceu a diminuição do peso corporal, do Índice de Massa Corporal, perímetros de cintura, abdômen, quadril e braço, aumento na freqüência ao urinar e evacuar, diminuição da ansiedade e apetite e aumento da auto-estima e melhor relação com o corpo. Conclusão: Conclui-se que o óleo essencial de Laranja Amarga pode ser um recurso eficaz no tratamento

  9. Desempenho na barra de tração de um trator agrícola de pneus, alimentado com misturas de óleo diesel e óleo de soja reutilizado

    Directory of Open Access Journals (Sweden)

    Wagner da Cunha Siqueira

    2013-12-01

    Full Text Available O petróleo é a principal fonte de energia para motores de combustão interna, possibilitando sua transformação em energia mecânica. A dependência do petróleo conduz à necessidade de alternativas, mediante o cultivo de matérias-primas renováveis. Os problemas atuais são os custos dos biocombustíveis, que são maiores que dos derivados do petróleo, e o fato de que não existem muitos motores de combustão adequados ao uso de óleos vegetais. Em vista disso, são necessárias mais investigações quanto às técnicas de produção e de refino dos biocombustíveis e, ainda, à adequação de motores ao uso de óleos vegetais, para que estes possam ser uma alternativa viável. O objetivo deste trabalho foi caracterizar as diferentes misturas e avaliar o desempenho de um trator agrícola de pneus, utilizando misturas de óleo Diesel (OD com óleo de soja reutilizável (OSR. Primeiramente, foi realizado um estudo de densidade, viscosidade das misturas e comportamento da temperatura do OD no sistema de alimentação de combustível no motor. Após as análises, verificou-se, por meio de ensaios na barra de tração, o desempenho das misturas de OD e OSR. As principais conclusões deste trabalho foram: a densidade e viscosidade das misturas sofrem variações com o aumento da quantidade de OSR e com a variação da temperatura. Para as avaliações na barra de tração, os melhores resultados observados no rendimento do trator foram verificados com o aumento das percentagens de mistura (25% OSR, para carga N, 25, 75 e 100% OSR, para a quarta marcha, como carga, e 75 e 100% OSR, para a terceira, segunda e primeira marcha, como carga.

  10. Acerca del postmodernismo en la música académica y la obra del compositor cubano Leo Brouwer

    OpenAIRE

    Gutiérrez Faxas, Ángel

    2013-01-01

    Una indagación teórico-filosófica sobre el fenómeno del postmodernismo en la Música Académica Occidental. Un análisis del compositor cubano Leo Brouwer a partir de los elementos postmodernos presentes en su obra.

  11. Chemistry and Kinematics of the Late-Forming Dwarf Irregular Galaxies Leo A, Aquarius, and Sagittarius DIG

    CERN Document Server

    Kirby, Evan N; Held, Enrico V; Cohen, Judith G; Cole, Andrew A; Manning, Ellen M; Skillman, Evan D; Weisz, Daniel R

    2016-01-01

    We present Keck/DEIMOS spectroscopy of individual stars in the relatively isolated Local Group dwarf galaxies Leo A, Aquarius, and the Sagittarius dwarf irregular galaxy. The three galaxies--but especially Leo A and Aquarius--share in common delayed star formation histories relative to many other isolated dwarf galaxies. The stars in all three galaxies are supported by dispersion. We found no evidence of stellar velocity structure, even for Aquarius, which has rotating HI gas. The velocity dispersions indicate that all three galaxies are dark matter-dominated, with dark-to-baryonic mass ratios ranging from $4.4^{+1.1}_{-0.8}$ (SagDIG) to $9.6^{+2.5}_{-1.8}$ (Aquarius). Leo A and SagDIG have lower stellar metallicities than Aquarius, and they also have higher gas fractions, both of which would be expected if Aquarius were farther along in its chemical evolution. The metallicity distribution of Leo A is inconsistent with a Closed or Leaky Box model of chemical evolution, suggesting that the galaxy was pre-enric...

  12. Einige Bemerkungen über den Kaplöwen, Panthera leo melanochaitus (Ch. H. Smith, 1842)

    NARCIS (Netherlands)

    Mazak, V.

    1960-01-01

    In seinen Katalogen der Sammlungen des Leidener Museums führt Jentink (1887, p. 81; 1892, p. 95) zwei Schädel und ein aufgestelltes Exemplar von Felis leo Linnaeus an, welche aus der Kap-Kolonie stammen. Leider sind die genauen Fundorte, die Fangdaten und die Sammler unbekannt, ebenso der Weg, auf d

  13. Genetic diversity, evolutionary history and implications for conservation of the lion (Panthera leo) in West and Central Africa

    NARCIS (Netherlands)

    Bertola, L. D.; Van Hooft, W. F.; Vrieling, K.; Uit de Weerd, D. R.; York, D. S.; Bauer, H.; Prins, H. H. T.; Funston, P. J.; Udo de Haes, H. A.; Leirs, H.; Van Haeringen, W. A.; Sogbohossou, E.; Tumenta, P. N.; De Iongh, H. H.

    2012-01-01

    Aim: In recent decades there has been a marked decline in the numbers of African lions (Panthera leo), especially in West Africa where the species is regionally endangered. Based on the climatological history of western Africa, we hypothesize that West and Central African lions have a unique evoluti

  14. From Leo Strauss to Collapse Theory: Considering the Neoconservative Attack on Modernity and the Work of Education

    Science.gov (United States)

    Smith, David Geoffrey

    2008-01-01

    This paper locates the work of Leo Strauss within the broader conservative assault on modernity and especially its roots in liberalism. Four themes from Strauss's work are identified, then hermeneutically engaged for their relevance to educational practice in global times. The four themes are: (1) the liberal/modern concept of an open society is…

  15. Frontiers in Laser Cooling, Single-Molecule Biophysics, and Enrgy Science: A Talk from Leo Holberg and Allen Mills

    Energy Technology Data Exchange (ETDEWEB)

    Holberg, Leo; Mills, Allen [NIST

    2008-08-30

    Leo Holberg and Allen Mills present a talk at Frontiers in Laser Cooling, Single-Molecule Biophysics and Energy Science, a scientific symposium honoring Steve Chu, director of Lawrence Berkeley National Laboratory and recipient of the 1997 Nobel Prize in Physics. The symposium was held August 30, 2008 in Berkeley.

  16. ALFALFA Discovery of the Nearby Gas-Rich Dwarf Galaxy Leo~P. III. An Extremely Metal Deficient Galaxy

    CERN Document Server

    Skillman, Evan D; Berg, Danielle A; Pogge, Richard W; Haurberg, Nathalie C; Cannon, John M; Aver, Erik; Olive, Keith A; Giovanelli, Riccardo; Haynes, Martha P; Adams, Elizabeth A K; McQuinn, Kristen B W; Rhode, Katherine L

    2013-01-01

    We present KPNO 4-m and LBT/MODS spectroscopic observations of an HII region in the nearby dwarf irregular galaxy Leo P discovered recently in the Arecibo ALFALFA survey. In both observations, we are able to accurately measure the temperature sensitive [O III] 4363 Angstrom line and determine a "direct" oxygen abundance of 12 + log(O/H) = 7.17 +/- 0.04. Thus, Leo P is an extremely metal deficient (XMD) galaxy, and, indeed, one of the most metal deficient star-forming galaxies ever observed. For its estimated luminosity, Leo P is consistent with the relationship between luminosity and oxygen abundance seen in nearby dwarf galaxies. Leo P shows normal alpha element abundance ratios (Ne/O, S/O, and Ar/O) when compared to other XMD galaxies, but elevated N/O, consistent with the "delayed release" hypothesis for N/O abundances. We derive a helium mass fraction of 0.2509 +0.0184 -0.0123 which compares well with the WMAP + BBN prediction of 0.2483 +/- 0.0002 for the primordial helium abundance. We suggest that surve...

  17. 95 päeva sõjatandril, päevik tagataskus / Leo Kunnas ; interv. Erkki Bahovski

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kolonelleitnant Leo Kunnas räägib Iraagi sissisõjast ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", mis põhineb tema Iraagi-kogemustel. Vt. samas: Sõda, kus eestlane on sisside vastu

  18. Variable stars in Leo A : RR Lyrae stars, short-period cepheids, and implications for stellar content

    NARCIS (Netherlands)

    Dolphin, AE; Saha, A; Claver, J; Skillman, ED; Cole, AA; Gallagher, JS; Tolstoy, E; Dohm-Palmer, RC; Mateo, M

    2002-01-01

    We present the results of a search for short-period variable stars in Leo A. We have found 92 candidate variables, including eight candidate RR Lyrae stars. From the RR Lyrae stars, we measure a distance modulus of (m - M)(0) = 24.51 +/- 0.12, or 0.80 +/- 0.04 Mpc. This discovery of RR Lyrae stars c

  19. Análise térmica do óleo de linhaça natural e oxidado

    Directory of Open Access Journals (Sweden)

    Marcelo Marques da Fonseca

    2010-05-01

    Full Text Available O óleo de Linhaça é um óleo natural constituído basicamente de triacilglicerol contendo alta porcentagem de ácidos graxos poliinsaturados que têm suas propriedades físico-químicas alteradas durante o processo de oxidação. Muitos estudos têm sido realizados para compreender o processo oxidativo que ocorre em óleos vegetais e para determinar os compostos formados durante a auto-oxidação destes materiais. A Termogravimetria (TG, a Análise Térmica Diferencial (DTA e a Calorimetria Exploratória Diferencial (DSC têm sido utilizadas principalmente no estudo da estabilidade térmica de materiais combustíveis e ainda são escassas no estudo do comportamento térmico do óleo de linhaça, por ser amplamente utilizado na fabricação de materiais pictóricos. Assim, avaliou-se o comportamento térmico do óleo de linhaça natural e envelhecido artificialmente por TG/DTG e por DTA, em atmosfera dinâmica de ar sintético e nitrogênio. Os resultados mostraram que, em atmosfera de nitrogênio, as amostras se decompõem em um estágio entre 30°C e 490°C, com perda de aproximadamente 95% da massa inicial. Em atmosfera dinâmica de ar sintético, as amostras reagem com o gás oxigênio e se decompõem em três estágios entre 30°C e 550°C formando 4,5% (massa de resíduo. A diferença no processo de decomposição está relacionada com a complexidade da matriz e dos mecanismos envolvidos na auto-oxidação do óleo. Os espectros Infravermelhos (IV destas amostras revelam que vários compostos oxigenados são formados durante o envelhecimento do óleo.

  20. Actividade antimicrobiana do óleo essencial do Foeniculum vulgare Miller Antimicrobial activity of Foeniculum vulgare Miller essential oil

    Directory of Open Access Journals (Sweden)

    M. T. Tinoco

    2007-01-01

    Full Text Available O Foeniculum vulgare Mill. subsp. vulgare é uma planta espontânea da região mediterrânea, pertencente à família Apiaceae. O seu óleo essencial, principalmente o dos frutos secos, é amplamente utilizado nas indústrias alimentar, farmacêutica, cosmética e perfumaria. Neste trabalho, pretendeu-se avaliar a actividade antimicrobiana do óleo essencial dos frutos verdes e das folhas da variedade de funcho doce colhido no Alentejo, na região de Évora, e relacionar essa actividade com a respectiva composição química. A extracção dos óleos essenciais foi efectuada por hidrodestilação e a sua análise foi feita por GC-FID e GC-MS. No óleo das folhas foram identificados como componentes maioritários os fenilpropanóides anetol, fenchona e estragol e o monoterpeno a-felandreno, enquanto que o óleo dos frutos apresentou como constituintes predominantes anetol e fenchona. A actividade antimicrobiana dos óleos foi avaliada face às estirpes Staphylococcus aureus, Escherichia coli, Saccharomyces spp., Fusarium oxysporum e Penicillium sp.. Os óleos essenciais apresentaram actividade antimicrobiana contra S. aureus, Saccharomyces spp. e Fusarium oxysporum.Foeniculum vulgare Mill. ssp. vulgare is a spontaneous plant of Mediterranean region that belongs to the Apiaceae family. Its essential oil is used as additives in food, pharmaceutical, cosmetic and perfume industries mainly that one obtained from dried seeds. The main goal of this work were to evaluate the antimicrobial activity of essential oils obtained from fresh leaves and unripe seeds of sweet fennel, collected in Évora-Alentejo, in face of their chemical composition. The extraction of the essentials oils was made by hydrodistillation. Chemical analyses were carried out by GC-FID and GCMS. Phenylpropanoides anethole, fenchone, estragole and the monoterpene aphellandrene were the most abundant compounds of leaves essential oil. Seeds essential oil showed as main components

  1. Rendimento e Características Físicas dos Óleos de Nim (Azadirachta indica e Mamona (Ricinus communis

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    Full Text Available A pesquisa objetivou avaliar o rendimento e a viscosidade de óleos de nim (Azadirachta indica e mamona (Ricinus communis. Os frutos de nim foram coletados no Núcleo de Pesquisa do Semiárido, em Patos, Paraíba, e os de mamona, às margens do Rio Espinharas, Patos e em Igaracy, Paraíba. Os frutos foram beneficiados no Laboratório de Tecnologia de Produtos Florestais, em Patos. Foram retiradas amostras de sementes para a determinação do teor de umidade e do rendimento em óleos. Os óleos foram extraídos com álcool etílico absoluto e empregados no preparo de soluções com os óleos de nim e mamona. Determinaram-se a densidade e a viscosidade das soluções. A mamona teve menor teor de umidade e rendimento em óleo que o nim. A densidade e a viscosidade do óleo de nim foram menores que o da mamona. Uma maior quantidade de óleos de mamona proporcionou aumento na densidade e na viscosidade das soluções preparadas.

  2. Caracterização química e atividade antibacteriana de óleos essenciais de plantas condimentares e medicinais contra Staphylococcus aureus e Escherichia coli

    Directory of Open Access Journals (Sweden)

    A.F. Millezi

    2014-03-01

    Full Text Available Os óleos essenciais são metabólitos secundários dos vegetais com propriedades biológicas diferenciadas, dentre elas, a atividade contra microrganismos, sendo de interesse da indústria de alimentos as concentrações mínimas inibitórias (CMI desses óleos para diversas bactérias. As CMI variam em função dos compostos majoritários e da espécie de bactéria. Nesta pesquisa, os óleos essenciais das plantas Satureja montana L., Cymbopogon nardus L. e Citrus limonia Osbeck foram caracterizados quimicamente e se determinou a CMI sobre as bactérias Staphylococcus aureus ATCC 2592 e Escherichia coli ATCC 25922. A CMI dos óleos testados contra E. coli e S. aureus foi de 1,5%, exceto para o óleo essencial de S. montana sobre S. aureus, a qual foi sensível a este óleo a partir da concentração de 5,0%. Sobre a constituição química, os componentes majoritários dos óleos de S. montana, C. narduse C. limonia Osbeck foram respectivamente o timol, citronelal e limoneno.

  3. Modeling of LEO Orbital Debris Populations in Centimeter and Millimeter Size Regimes

    Science.gov (United States)

    Xu, Y.-L.; Hill, . M.; Horstman, M.; Krisko, P. H.; Liou, J.-C.; Matney, M.; Stansbery, E. G.

    2010-01-01

    The building of the NASA Orbital Debris Engineering Model, whether ORDEM2000 or its recently updated version ORDEM2010, uses as its foundation a number of model debris populations, each truncated at a minimum object-size ranging from 10 micron to 1 m. This paper discusses the development of the ORDEM2010 model debris populations in LEO (low Earth orbit), focusing on centimeter (smaller than 10 cm) and millimeter size regimes. Primary data sets used in the statistical derivation of the cm- and mm-size model populations are from the Haystack radar operated in a staring mode. Unlike cataloged objects of sizes greater than approximately 10 cm, ground-based radars monitor smaller-size debris only in a statistical manner instead of tracking every piece. The mono-static Haystack radar can detect debris as small as approximately 5 mm at moderate LEO altitudes. Estimation of millimeter debris populations (for objects smaller than approximately 6 mm) rests largely on Goldstone radar measurements. The bi-static Goldstone radar can detect 2- to 3-mm objects. The modeling of the cm- and mm-debris populations follows the general approach to developing other ORDEM2010-required model populations for various components and types of debris. It relies on appropriate reference populations to provide necessary prior information on the orbital structures and other important characteristics of the debris objects. NASA's LEO-to-GEO Environment Debris (LEGEND) model is capable of furnishing such reference populations in the desired size range. A Bayesian statistical inference process, commonly adopted in ORDEM2010 model-population derivations, changes a priori distribution into a posteriori distribution and thus refines the reference populations in terms of data. This paper describes key elements and major steps in the statistical derivations of the cm- and mm-size debris populations and presents results. Due to lack of data for near 1-mm sizes, the model populations of 1- to 3.16-mm

  4. Tratamiento de la alveolitis dental con tintura de propóleos al 5 %

    Directory of Open Access Journals (Sweden)

    Ada Vivian Bravo Venero

    Full Text Available Objetivo: comparar la efectividad entre el tratamiento con tintura de propóleos al 5 % y el tratamiento farmacológico convencional en pacientes diagnosticados con alveolitis dental. Métodos: se realizó un estudio descriptivo, prospectivo, de corte longitudinal de casos y controles en la Clínica Estomatológica "José Martí" del municipio Consolación del Sur, durante el 2009. El universo estuvo constituido por 90 pacientes, los cuales se dividieron en dos grupos de tratamiento diferentes de manera aleatoria, teniendo en cuenta un grupo de casos (grupo I conformado por 30 pacientes a los que se les aplicó tratamiento con tintura de propóleos al 5 %, y otro grupo de controles (grupo II con 60 pacientes tratados con la terapéutica medicamentosa convencional. Para el procesamiento de los datos se utilizaron métodos de estadística descriptiva e inferencial. Resultados: en ambos grupos de tratamiento prevaleció el sexo femenino y hubo un predominio de la alveolitis en el grupo de edad entre los 46 y 60 años. El grupo I logró la remisión de los síntomas entre el segundo (36,6 % y el tercer días de tratamiento (60 % y solo un paciente requirió tratamiento por 5 días; mientras el grupo II requirió de un mayor período para la evolución del cuadro, entre 5 y 7 días de tratamiento para un 61,3 % (27 pacientes y 23,3 % (14 pacientes. Conclusiones: el tratamiento con tintura de propóleos al 5 % resultó altamente efectivo, pues aportó una remisión más notoria de los síntomas, ya que se observó una disminución de estos, así como la disminución del número de sesiones necesarias, lo que permite recomendarlo como una opción terapéutica adecuada.

  5. GPU-accelerated Faint Streak Detection for Uncued Surveillance of LEO

    Science.gov (United States)

    Zimmer, P.; Ackermann, M.; McGraw, J. T.

    2013-09-01

    By astronomical standards, small objects (<10cm) in LEO illuminated by the Sun under terminator conditions are quite bright, depositing 100's to 1000's of photons per second into small telescope apertures (< 1m diameter). The challenge in discovering these objects with no a priori knowledge of their orbit (i.e. uncued surveillance) is that their relative motion with respect to a ground-based telescope makes them appear to have large angular rates of motion, up to and exceeding 1 degree per second. Thus in even a short exposure, the signal from the object is smeared out in a streak with low signal-to-noise per pixel. Go Green Termite (GGT), Inc. of Gilroy, CA, in collaboration with the University of New Mexico (UNM), is building two proof-of-concept wide-field imaging systems to test, develop and prove a novel streak detection technique. The imaging systems are built from off-the-shelf optics and detectors resulting in a 350mm aperture and a 6 square degree field of view. For streak detection, field of view is of critical importance because the maximum exposure time on the object is limited by its crossing time. In this way, wider fields of view impact surveys for LEO objects both by increasing the survey volume and increasing sensitivity. Using our newly GPU-accelerated detection scheme, the proof-of-concept systems are expected to be able to detect objects fainter than 12th magnitude moving at 1 degree per second and possibly as faint as 13th magnitude for slower moving objects. Meter-class optical systems using these techniques should be able to detect objects fainter than 14th magnitude, which is roughly equivalent to a golf ball at 1000km altitude. The goal of this work is to demonstrate a scalable system for near real time detection of fast moving objects that can be then handed off to other instruments capable of tracking and characterizing them. The two proof-of-concept systems, separated by ~30km, work together by taking simultaneous images of the same

  6. Simulation of the space debris environment in LEO using a simplified approach

    Science.gov (United States)

    Kebschull, Christopher; Scheidemann, Philipp; Hesselbach, Sebastian; Radtke, Jonas; Braun, Vitali; Krag, H.; Stoll, Enrico

    2017-01-01

    Several numerical approaches exist to simulate the evolution of the space debris environment. These simulations usually rely on the propagation of a large population of objects in order to determine the collision probability for each object. Explosion and collision events are triggered randomly using a Monte-Carlo (MC) approach. So in many different scenarios different objects are fragmented and contribute to a different version of the space debris environment. The results of the single Monte-Carlo runs therefore represent the whole spectrum of possible evolutions of the space debris environment. For the comparison of different scenarios, in general the average of all MC runs together with its standard deviation is used. This method is computationally very expensive due to the propagation of thousands of objects over long timeframes and the application of the MC method. At the Institute of Space Systems (IRAS) a model capable of describing the evolution of the space debris environment has been developed and implemented. The model is based on source and sink mechanisms, where yearly launches as well as collisions and explosions are considered as sources. The natural decay and post mission disposal measures are the only sink mechanisms. This method reduces the computational costs tremendously. In order to achieve this benefit a few simplifications have been applied. The approach of the model partitions the Low Earth Orbit (LEO) region into altitude shells. Only two kinds of objects are considered, intact bodies and fragments, which are also divided into diameter bins. As an extension to a previously presented model the eccentricity has additionally been taken into account with 67 eccentricity bins. While a set of differential equations has been implemented in a generic manner, the Euler method was chosen to integrate the equations for a given time span. For this paper parameters have been derived so that the model is able to reflect the results of the numerical MC

  7. Analysis on Autotracking Technology of LEO Satellite%低轨卫星自跟踪技术分析

    Institute of Scientific and Technical Information of China (English)

    姚勇

    2011-01-01

    针对低轨(LEO)卫星无信标信号时,传统自跟踪方式无法对其进行有效跟踪的问题,提出了全数字跟踪体制。对采用频分时分复合多址(FDMA/TDMA)体制的低轨卫星,采用宽带检测结合窄带跟踪的方法,快速准确地提取方位俯仰误差,实现了对目标卫星的高精度跟踪。对采用码分多址(CDMA)体制的低轨卫星,采用频域跟踪的方法,实现了低信噪比条件下对目标卫星的高精度跟踪。%The traditional autotracking method can't implement effective tracking for LEO satellite without beacon signal.To solve this problem,an all-digit tracking method is proposed in this paper.For the LEO satellite operating in FDMA/TDMA mode,this method combining narrowband tracking with wideband detection can quickly and accurately extract the errors of azimuth and elevation and fulfills the tracking with high precision.For the LEO satellite operating in CDMA mode,this algorithm extracting tracking error in frequency domain can precisely track the LEO satellite with low SNR signal of LEO.

  8. Actividad antibacteriana de un extracto acuoso de propóleo del municipio de Irapuato, Guanajuato, México.

    Directory of Open Access Journals (Sweden)

    Carlos Manuel Bucio-Villalobos

    2016-12-01

    Full Text Available El objetivo del presente trabajo fue evaluar la actividad antibacteriana de un extracto acuoso de propóleo. En febrero de 2015 se colectó el propóleo en un apiario ubicado en Irapuato, Guanajuato, México. 300 g de propóleo fueron fraccionados y adicionados a 500 ml de etanol al 70%, en agitación continua por quince días. Por ltración al vacío, se separó la fase líquida, y el etanol contenido en ella fue evaporado en un rotoevaporador accionado a noventa revoluciones por minuto (rpm y 80 oC. El residuo nal fue resuspendido en agua destilada, obteniéndose así el extracto acuoso. Un extracto de propóleo obtenido con etanol concentrado fue utilizado como control de referencia, además se incluyeron controles de etanol y agua. La actividad antibacteriana de los extractos fue evaluada mediante la técnica de difusión en agar, utilizando cepas de Escherichia coli (ATCC-10536, Salmonella typhimurium (ATCC-13311, Listeria monocytogenes (ATCC-19115 y Staphylococcus aureus (ATCC-11632, desarrolladas en tripticaseina-soya- agar, incubadas a 37 °C por veinticuatro horas (h y se midió el halo de inhibición al término de dicho tiempo. Solo el extracto etanólico usado como control tuvo actividad antimicrobiana contra S. aureus y L. monocytogenes, más no se encontró respuesta para E. coli y S. typhimurium. El extracto acuoso no tuvo efecto sobre ninguna de las cuatro bacterias evaluadas, concluyéndose que los ingredientes activos del propóleo no son solubles en agua, por lo que se pierden en un proceso de extracción acuosa.

  9. Time variable gravity retrieval and treatment of temporal aliasing using optical two-way links between GALILEO and LEO satellites

    Science.gov (United States)

    Hauk, Markus; Pail, Roland; Murböck, Michael; Schlicht, Anja

    2016-04-01

    For the determination of temporal gravity fields satellite missions such as GRACE (Gravity Recovery and Climate Experiment) or CHAMP (Challenging Minisatellite Payload) were used in the last decade. These missions improved the knowledge of atmospheric, oceanic and tidal mass variations. The most limiting factor of temporal gravity retrieval quality is temporal aliasing due to the undersampling of high frequency signals, especially in the atmosphere and oceans. This kind of error causes the typical stripes in spatial representations of global gravity fields such as from GRACE. As part of the GETRIS (Geodesy and Time Reference in Space) mission, that aims to establish a geodetic reference station and precise time- and frequency reference in space by using optical two-way communication links between geostationary (GEO) and low Earth orbiting (LEO) satellites, a possible future gravity field mission can be set up. By expanding the GETRIS space segment to the global satellite navigation systems (GNSS) the optical two-way links also connect the GALILEO satellites among themselves and to LEO satellites. From these links between GALILEO and LEO satellites gravitational information can be extracted. In our simulations inter-satellite links between GALILEO and LEO satellites are used to determine temporal changes in the Earth's gravitational field. One of the main goals of this work is to find a suitable constellation together with the best analysis method to reduce temporal aliasing errors. Concerning non-tidal aliasing, it could be shown that the co-estimation of short-period long-wavelength gravity field signals, the so-called Wiese approach, is a powerful method for aliasing reduction (Wiese et al. 2013). By means of a closed loop mission simulator using inter-satellite observations as acceleration differences along the line-of-sight, different mission scenarios for GALILEO-LEO inter-satellite links and different functional models like the Wiese approach are analysed.

  10. ALFALFA DISCOVERY OF THE NEARBY GAS-RICH DWARF GALAXY LEO P. III. AN EXTREMELY METAL DEFICIENT GALAXY

    Energy Technology Data Exchange (ETDEWEB)

    Skillman, Evan D.; Berg, Danielle A.; Olive, Keith A.; McQuinn, Kristen B. W., E-mail: skillman@astro.umn.edu, E-mail: berg@astro.umn.edu, E-mail: olive@physics.umn.edu, E-mail: kmcquinn@astro.umn.edu [Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, MN 55455 (United States); and others

    2013-07-01

    We present KPNO 4 m and LBT/MODS spectroscopic observations of an H II region in the nearby dwarf irregular galaxy Leo P discovered recently in the Arecibo ALFALFA survey. In both observations, we are able to accurately measure the temperature sensitive [O III] {lambda}4363 line and determine a ''direct'' oxygen abundance of 12 + log(O/H) = 7.17 {+-} 0.04. Thus, Leo P is an extremely metal deficient (XMD) galaxy, and, indeed, one of the most metal deficient star-forming galaxies ever observed. For its estimated luminosity, Leo P is consistent with the relationship between luminosity and oxygen abundance seen in nearby dwarf galaxies. Leo P shows normal {alpha} element abundance ratios (Ne/O, S/O, and Ar/O) when compared to other XMD galaxies, but elevated N/O, consistent with the ''delayed release'' hypothesis for N/O abundances. We derive a helium mass fraction of 0.2509{sup +0.0184}{sub -0.0123}, which compares well with the WMAP + BBN prediction of 0.2483 {+-} 0.0002 for the primordial helium abundance. We suggest that surveys of very low mass galaxies compete well with emission line galaxy surveys for finding XMD galaxies. It is possible that XMD galaxies may be divided into two classes: the relatively rare XMD emission line galaxies which are associated with starbursts triggered by infall of low-metallicity gas and the more common, relatively quiescent XMD galaxies like Leo P, with very low chemical abundances due to their intrinsically small masses.

  11. Estudos dos constituintes químicos e atividade antibacteriana do óleo essencial de Lippia gracilis a Xanthomonas campestris pv. viticola in vitro.

    OpenAIRE

    2015-01-01

    Este trabalho foi realizado com o objetivo de estudar a eficácia de óleos essenciais de Lippia gracilis, no crescimento in vitro de Xcv. Foram utilizados oito óleos extraídos de L. gracilis, obtidos de diferentes manejos de cultivo, em três dosagens diferentes (200; 250 e 300 µL.L-1), testemunha com o oxicloreto de cobre (controle padrão) e a testemunha absoluta. A suscetibilidade do isolado Xcv3 aos óleos testados foi avaliada na primeira etapa pela presença e ausência do crescimento bacteri...

  12. CARACTERIZAÇÃO E AVALIAÇÃO DA ATIVIDADE LARVICIDA DO ÓLEO ESSENCIAL DO Zingiber officinale Roscoe (GENGIBRE) FRENTE AO MOSQUITO Aedes aegypti

    OpenAIRE

    ANDRESON LEANDRO SANTANA SILVA

    2012-01-01

    Na procura pelo controle químico alternativo contra o mosquito Aedes aegypti, diversas pesquisas são desenvolvidas e estimuladas no intuito de descobrirem novas substâncias inseticidas de origem vegetal. Neste trabalho a partir da extração e do estudo analítico do óleo essencial dos rizomas do Zingiber officinale Roscoe, foi analisado o efeito larvicida do óleo contra larvas em terceiro estágio do mosquito Aedes aegypti (Linnaeus, 1792). Extraiu-se quantitativamente o óleo essencial por hidro...

  13. Caracterización de propóleos provenientes del municipio de Caldas obtenido por dos métodos de recolección

    OpenAIRE

    Julián Martínez G.; Carlos Garcia P.; Diego Durango R.; Jesús Gil G.

    2012-01-01

    RESUMENObjetivo. Determinar las características fisicoquímicas y la actividad antimicrobiana de propóleos de Apis mellifera, provenientes del municipio de Caldas, obtenidos por dos métodos de recolección. Materiales y métodos. Se utilizaron dos métodos de recolección: de raspado y trampa plastica. Se estableció el contenido de cera, ceniza, material insoluble y resina de los propóleos crudos. Al extracto etanólico de los propóleos se les determinó el perfil cromatográfico (GC-MS) y el espectr...

  14. ESTUDO QUÍMICO E ATIVIDADE LARVICIDA FRENTE AO Aedes aegypti DO ÓLEO ESSENCIAL DAS FOLHAS DE Cinnamomum zeylanicum Breyn (CANELA)

    OpenAIRE

    LEANDRA SOFIA DOS SANTOS MENDES

    2012-01-01

    Na procura pelo controle químico alternativo contra o mosquito Aedes aegypti, diversas pesquisas são desenvolvidas e estimuladas no intuito de se descobrir novas substâncias inseticidas de origem vegetal. Neste trabalho, a partir da extração e do estudo analítico do óleo essencial das folhas de Cinnamomum zeylanicum Breyn (canela), foi analisado o efeito larvicida do óleo contra larvas em terceiro estágio do mosquito Aedes aegypti. Extraiu-se quantitavamente o óleo essencial da...

  15. Análise de viabilidade de injeção de fluidos alternativos ao vapor em reservatórios de óleo pesado

    OpenAIRE

    Rodrigues, Marcos Allyson Felipe

    2012-01-01

    Muitas das reservas de hidrocarbonetos existentes em todo o mundo são formadas por óleos pesados (°API entre 10 e 20). Além disso, vários campos de óleo pesado estão maduros e, portanto, oferecem grandes desafios para a indústria do petróleo. Entre os métodos térmicos utilizados para recuperar estes recursos, a injeção de vapor tem sido a principal alternativa economicamente viável. O calor latente transportado por meio de vapor aquece o reservatório, reduzindo a viscosidade do...

  16. Composição química e atividade in vitro de três óleos essenciais sobre Colletotrichum gloeosporioides do maracujazeiro

    Directory of Open Access Journals (Sweden)

    C.F. Aquino

    2014-01-01

    Full Text Available Objetivou-se avaliar a ação de diferentes concentrações de óleos essenciais de três plantas medicinais sobre o crescimento micelial, a produção e a germinação de conídios de Colletotrichum gloeosporioides (Penz.. Utilizou-se os óleos essenciais de Lippia sidoides Cham., Cymbopogon citratus (DC Stapf. e Ocimum gratissimum L. em cinco concentrações (0 µL mL-1, 1 µL mL-1, 3 µL mL-1, 5 µL mL-1 e 7 µL mL-1 com 4 repetições no delineamento inteiramente casualizado, em esquema fatorial 5x3. Os óleos foram analisados por cromatografia gasosa acoplada com espectrometria de massas. Para todas as características verificou-se efeito significativo da interação "Óleo" versus "Concentração". O óleo essencial de C. citratus proporcionou a maior inibição do crescimento micelial em todas as concentrações testadas. Os outros óleos não se diferenciaram, exceto a partir da concentração de 5 µL mL-1, onde o óleo de L. sidoides foi superior ao óleo de O. gratissimum. Na produção e germinação de conídios, o óleo de C. citratus, foi superior aos óleos de L. sidoides e de O. gratissimum nas concentrações de 1 µL mL-1 e 3 µL mL-1, inibindo completamente a produção e germinação a partir da concentração de 3 µL mL-1. As concentrações influenciam em todas as variáveis, ajustando-se à equação do modelo linear. Observa-se o decréscimo nessas, à medida em que se aumentam as concentrações dos óleos testados. Os óleos essenciais testados possuem efeito fungitóxico e fungistático.

  17. Ambiguity resolution performance with GPS and BeiDou for LEO formation flying

    Science.gov (United States)

    Verhagen, Sandra; Teunissen, Peter J. G.

    2014-09-01

    The evolving BeiDou Navigation Satellite System constellation brings new opportunities for high-precision applications. In this contribution the focus will be on one such application, namely precise and instantaneous relative navigation of a formation of LEO satellites. The aim is to assess the ambiguity resolution performance with the future GPS and BeiDou constellations depending on system choice (GPS, BeiDou, or GPS+BeiDou), single- or dual-frequency observations, receiver noise, and uncertainties in ionosphere modelling. In addition, for the GPS+BeiDou constellation it will be shown how the growing BeiDou constellation in the years to come can already bring an important performance improvement compared to the GPS-only case. The performance will be assessed based on the percentage of time that the required precision can be obtained with a partial ambiguity resolution strategy.

  18. ALFALFA DISCOVERY OF THE NEARBY GAS-RICH DWARF GALAXY LEO P. II. OPTICAL IMAGING OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Rhode, Katherine L.; Salzer, John J.; Haurberg, Nathalie C.; Van Sistine, Angela; Young, Michael D. [Department of Astronomy, Indiana University, 727 East Third Street, Bloomington, IN 47405 (United States); Haynes, Martha P.; Giovanelli, Riccardo; Adams, Elizabeth A. K. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, Saint Paul, MN 55105 (United States); Skillman, Evan D.; McQuinn, Kristen B. W., E-mail: rhode@astro.indiana.edu, E-mail: slaz@astro.indiana.edu, E-mail: riccardo@astro.cornell.edu, E-mail: haynes@astro.cornell.edu, E-mail: betsey@astro.cornell.edu, E-mail: jcannon@macalester.edu, E-mail: skillman@astro.umn.edu, E-mail: kmcquinn@astro.umn.edu [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States)

    2013-06-15

    We present results from ground-based optical imaging of a low-mass dwarf galaxy discovered by the ALFALFA 21 cm H I survey. Broadband (BVR) data obtained with the WIYN 3.5 m telescope at Kitt Peak National Observatory (KPNO) are used to construct color-magnitude diagrams of the galaxy's stellar population down to V{sub o} {approx} 25. We also use narrowband H{alpha} imaging from the KPNO 2.1 m telescope to identify a H II region in the galaxy. We use these data to constrain the distance to the galaxy to be between 1.5 and 2.0 Mpc. This places Leo P within the Local Volume but beyond the Local Group. Its properties are extreme: it is the lowest-mass system known that contains significant amounts of gas and is currently forming stars.

  19. Esophageal hiatal hernia in three exotic felines--Lynx lynx, Puma concolore, Panthera leo.

    Science.gov (United States)

    Hettlich, Bianca F; Hobson, H Phil; Ducoté, Julie; Fossum, Theresa W; Johnson, James H

    2010-03-01

    Hiatal hernia was diagnosed in three exotic felines-lynx (Lynx lynx), cougar (Puma concolore), and lion (Panthera leo). All cats had a history of anorexia. Thoracic and abdominal radiographs showed evidence of a soft tissue mass within the caudal mediastinum suggestive of a hiatal hernia in all animals. A barium esophagram was performed in one case. All animals underwent thoracic or abdominal surgery for hernia reduction. Surgical procedures included: intercostal thoracotomy with herniorrhaphy and esophagopexy (lynx and cougar), and incisional gastropexy (lion). Concurrent surgical procedures performed were gastrotomy for gastric foreign body removal and jejunostomy tube placement. Clinical signs related to the hiatal hernia disappeared after surgery and recurrence of signs was not reported for the time of follow-up.

  20. The first case report of Leishmania (leishmania) chagasi in Panthera leo in Brazil.

    Science.gov (United States)

    Dahroug, Magyda A A; Almeida, Arleana B P F; Sousa, Valéria R F; Dutra, Valéria; Guimarães, Luciana D; Soares, César E; Nakazato, Luciano; de Souza, Roberto L

    2011-06-01

    We reported here the first known case of natural infection of a lion (Panthera leo-Linnaeus, 1758) with Leishmania (Leishmania) chagasi (L. chagasi) in Brazil. The specimen was created by a circus handler in the state of Mato Grosso and was donated to the zoological park of the Federal University of Mato Grosso. Infection by L. chagasi was detected using a PCR-RFLP test. It was known that the domestic felids can act as reservoir of infection of L. chagasi in endemic areas, making it important that studies demonstrate their participation in the epidemiological chain. We demonstrate in this work that wild animals can have an important role in the epidemiological chain and must be considered in order to plan methods of control of this zoonosis.

  1. Adaptive Distributed Load Balancing Routing Mechanism for LEO Satellite IP Networks

    Directory of Open Access Journals (Sweden)

    Xiao Ma

    2014-04-01

    Full Text Available LEO (Low Earth Orbit satellite constellation is an ideal scheme for the next generation wideband internet. The constellation is formed as a mesh-like network with inter satellite links (ISLs which are equipped between the neighbor satellites for transmitting directly. As to the future wideband IP services, an efficient routing mechanism will play an important role in improving the performance and balancing the network traffic. An Adaptive Distributed Load Balancing Routing Mechanism (ADLB is proposed in this paper to address the above-mentioned issues. This mechanism makes well-performed routing decision based on the current and historical status of each ISLs in each satellite node. With collecting historical information from network initiated, a proper mechanism is contained in ADLB for making required computing power and storage space in a reasonable range. The performance of ADLB is verified via a series of simulations which demonstrate that the scheme can provide better throughput and lower packet drop rate.

  2. Aviation-oriented Mobility Management Method in IP/LEO Satellite Networks

    Institute of Scientific and Technical Information of China (English)

    Guo Xin; Zhang Jun; Zhang Tao; Ding Yanwen

    2008-01-01

    Taking into chief consideration the features of aviation nodes in satellite networks,such as high moving speed,long communication distance,and high connection frequency,this article proposes an aviatiun-oriented mobility management method for IP/low earth orbit (LEO) satellite networks.By introducing the concept of ground station real-time coverage area,the proposed method uses ground-station-based IP addressing method and cell paging scheme to decrease the frequency of IP binding update requests as well as the paging cost.In comparison with the paging mobile IP (P-MIP) method and the handover-independent IP mobility management method,as is verified by the mathematical analysis and simulation,the proposed method could decrease the management cost.It also possesses better ability to support the aviation nodes because it is subjected to fewer influences from increased node speeds and newly coming connection rates.

  3. Performance Analysis of an Enhanced PRMA-HS Protocol for LEO Satellite Communication

    Institute of Scientific and Technical Information of China (English)

    ZHUO Yong-ning; YAN Shao-hu; WU Shi-qi

    2005-01-01

    The packet reservation multiple access with hindering state (PRMA-HS) is a protocol suitable for LEO satellite mobile communication. Although working well with light system payload (amount of user terminals), the protocol imposes high channel congestion on system with heavy payload, thus degrades the system's quality of service. To controlling the channel congestion, a scheme of enhanced PRMA-HS protocol is proposed, which aims to reduce the collision of voice packets by adopting a mechanism of access control. Through theoretic analysis, the system's mathematic model is presented and the packet drop probability of the scheme is deduced. To testify the performance of the scheme, a simulation is performed and the results support our analysis.

  4. A Novel Probability-Based Handoff Strategy for Multimedia LEO Satellite Communications

    Institute of Scientific and Technical Information of China (English)

    HUANG Fei; ZHU Li-dong; WU Shi-qi

    2007-01-01

    A novel bandwidth allocation strategy and a connection admission control technique are proposed to improve the utilization of network resource and provide the network with better quality of service (QoS) guarantees in multimedia low earth orbit (LEO) satellite networks. Our connection admission control scheme, we call the probability based dynamic channel reservation strategy (PDR), dynamically reserves bandwidth for real-time services based on their handoff probability. And the reserved bandwidth for real-time handoff connection can also be used by new connections under a certain probability determined by the mobility characteristics and bandwidth usage of the system. Simulation results show that our scheme not only lowers the call dropping probability (CDP) for Class I real-time service but also maintains the call blocking probability (CBP) to certain degree. Consequently, the scheme can offer very low CDP for real-time connections while keeping resource utilization high.

  5. A CRIRES-POP Atlas of the K Giant 10 Leo

    Science.gov (United States)

    Nicholls, C. P.; Lebzelter, T.

    2015-12-01

    The CRIRES-POP project (Lebzelter et al. [2]) will provide a public database of high-res, high S:N, NIR spectra of stars spanning the HR diagram. A relevant part of this library for the evolved star community will be the high quality reference spectra of several cool evolved giants. These atlases will be valuable references for future research, and will include comprehensive line identifications, abundance measurements, and isotope ratios, alongside stellar parameters derived through the inclusion of other data sources. All CRIRES observations have been completed, and reduction and analysis of the spectra, including improved telluric subtraction and wavelength calibration, is ongoing. We present here preliminary results of the first atlas to be produced, that of K1 III giant 10 Leo.

  6. The Multi-Wavelength Quasar Survey Ⅳ. Quasars in the Leo Cluster

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We aim to provide a quasar sample that is more complete than any previous surveys by using a combined selection technique to reduce the selection effects. Here we present the observational results for the X-ray candidates in the field of the Leo Cluster. We found 33 X-ray AGNs in this field of which 10 are new discoveries. The X-ray data and optical spectra of these AGNs are given. We also study the near-IR properties of the X-ray-selected AGNs by using the data from 2MASS. Most of the AGNs in our sample span the color range 0.0 < B- J < 2.5, 1.0 < J-Ks < 2.0 and 0.5 < H-Ks < 1.2.

  7. LEO high voltage solar array arcing response model. Interim report, February 1987

    Energy Technology Data Exchange (ETDEWEB)

    Metz, R.N.

    1987-02-01

    A series of mathematical models were developed that describe the electrical behavior of a large solar cell array floating electrically in the low Earth orbit (LEO) space plasma and struck by an arc at a point of negative bias. There are now three models in this series: ARCII, which is a fully analytical, linearized model; ARCIII, which is an extension of ARCIII that includes solar cell inductance as well as load reactance; Nonlinear ARC, which is a numerical model able to treat effects such as non-linearized, i.e., logarithmic solar cell I/V characteristics, conductance switching as a solar cell crosses plasma ground on a voltage excursion and non-ohmic plasma leakage current collection.

  8. A comprehensive design and performance analysis of LEO satellite quantum communication

    CERN Document Server

    Bourgoin, J -P; Higgins, B L; Helou, B; Erven, C; Huebel, H; Kumar, B; Hudson, D; D'Souza, I; Girard, R; Laflamme, R; Jennewein, T

    2012-01-01

    Optical quantum communication utilizing satellite platforms has the potential to extend the reach of quantum key distribution (QKD) from terrestrial limits of ~200 km to global scales. We have developed a thorough numerical simulation using realistic simulated orbits and incorporating the effects of pointing error, diffraction, atmosphere and telescope design, to obtain estimates of the loss and background noise which a satellite-based system would experience. Combining with quantum optics simulations of sources and detection, we determine the length of secure key for QKD, as well as entanglement visibility and achievable distances for fundamental experiments. We analyze the performance of a low Earth orbit (LEO) satellite for downlink and uplink scenarios of the quantum optical signals. We argue that the advantages of locating the quantum source on the ground justify a greater scientific interest in an uplink as compared to a downlink. An uplink with a ground transmitter of at least 25 cm diameter and a 30 c...

  9. ¿Adictos al petróleo? : una perspectiva latinoamericana

    Directory of Open Access Journals (Sweden)

    Mauricio Medinaceli Monrroy

    2013-10-01

    Full Text Available Una de las preocupaciones centrales en la política energética hoy en día es la elevada dependencia energética en los combustibles fósiles. Esto no sólo por los problemas ambientales asociados a su exploración y explotación, sino también por el reciente incremento en los precios internaciones del petróleo que, en países importadores, incrementa la llamada “factura petrolera” y, en países productores, genera rentas económicas que muchas veces alteran la estabilidad política de un país.

  10. Real time prediction and correction of ADCS problems in LEO satellites using fuzzy logic

    Directory of Open Access Journals (Sweden)

    Yassin Mounir Yassin

    2017-06-01

    Full Text Available This approach is concerned with adapting the operations of attitude determination and control subsystem (ADCS of low earth orbit LEO satellites through analyzing the telemetry readings received by mission control center, and then responding to ADCS off-nominal situations. This can be achieved by sending corrective operational Tele-commands within real time. Our approach is related to the fuzzy membership of off-nominal telemetry readings of corrective actions through a set of fuzzy rules based on understanding the ADCS modes resulted from the satellite telemetry readings. Response in real time gives us a chance to avoid risky situations. The approach is tested on the EgyptSat-1 engineering model, which is our method to simulate the results.

  11. Age Estimation of African Lions Panthera leo by Ratio of Tooth Areas.

    Science.gov (United States)

    White, Paula A; Ikanda, Dennis; Ferrante, Luigi; Chardonnet, Philippe; Mesochina, Pascal; Cameriere, Roberto

    2016-01-01

    Improved age estimation of African lions Panthera leo is needed to address a number of pressing conservation issues. Here we present a formula for estimating lion age to within six months of known age based on measuring the extent of pulp closure from X-rays, or Ratio Of tooth AReas (ROAR). Derived from measurements taken from lions aged 3-13 years for which exact ages were known, the formula explains 92% of the total variance. The method of calculating the pulp/tooth area ratio, which has been used extensively in forensic science, is novel in the study of lion aging. As a quantifiable measure, ROAR offers improved lion age estimates for population modeling and investigations of age-related mortality, and may assist national and international wildlife authorities in judging compliance with regulatory measures involving age.

  12. Age Estimation of African Lions Panthera leo by Ratio of Tooth Areas.

    Directory of Open Access Journals (Sweden)

    Paula A White

    Full Text Available Improved age estimation of African lions Panthera leo is needed to address a number of pressing conservation issues. Here we present a formula for estimating lion age to within six months of known age based on measuring the extent of pulp closure from X-rays, or Ratio Of tooth AReas (ROAR. Derived from measurements taken from lions aged 3-13 years for which exact ages were known, the formula explains 92% of the total variance. The method of calculating the pulp/tooth area ratio, which has been used extensively in forensic science, is novel in the study of lion aging. As a quantifiable measure, ROAR offers improved lion age estimates for population modeling and investigations of age-related mortality, and may assist national and international wildlife authorities in judging compliance with regulatory measures involving age.

  13. The first case report of Leishmania (leishmania chagasi in Panthera leo in Brazil

    Directory of Open Access Journals (Sweden)

    Magyda AA Dahroug

    2011-06-01

    Full Text Available We reported here the first known case of natural infection of a lion (Panthera leo-Linnaeus, 1758 with Leishmania (Leishmania chagasi (L. chagasi in Brazil. The specimen was created by a circus handler in the state of Mato Grosso and was donated to the zoological park of the Federal University of Mato Grosso. Infection by L. chagasi was detected using a PCR-RFLP test. It was known that the domestic felids can act as reservoir of infection of L. chagasi in endemic areas, making it important that studies demonstrate their participation in the epidemiological chain. We demonstrate in this work that wild animals can have an important role in the epidemiological chain and must be considered in order to plan methods of control of this zoonosis.

  14. Benzo(apireno em óleos de milho produzidos e comercializados no Brasil

    Directory of Open Access Journals (Sweden)

    TOLEDO M. Cecilia de F.

    1998-01-01

    Full Text Available Óleos de milho de diferentes marcas, produzidos e comercializados no Brasil, foram analisados quanto à presença de benzo(apireno (B(aP. A metodologia utilizada envolveu extração com ciclohexano, purificação em coluna de silica gel e determinação por cromatografia líquida de alta eficiência com detector de fluorescência. Todas amostras analisadas mostraram-se contaminadas por B(aP e os níveis determinados variaram entre as diferentes marcas analisadas e entre diferentes lotes de mesma marca, dentro da faixa de 0,85 a 25,17 µg/kg. Entre 49 amostras analisadas no período de dois anos, apenas uma apresentou nível de contaminação por B(aP abaixo do limite referencial de 1 µg/kg.

  15. Prediction of Retained Capacity and EODV of Li-ion Batteries in LEO Spacecraft Batteries

    CERN Document Server

    Ramakrishnan, S; Jeyakumar, A Ebenezer

    2010-01-01

    In resent years ANN is widely reported for modeling in different areas of science including electro chemistry. This includes modeling of different technological batteries such as lead acid battery, Nickel cadmium batteries etc. Lithium ion batteries are advance battery technology which satisfy most of the space mission requirements. Low earth orbit (LEO)space craft batteries undergo large number of charge discharge cycles (about 25000 cycles)compared to other ground level or space applications. This study is indented to develop ANN model for about 25000 cycles, cycled under various temperature, Depth Of Discharge (DOD) settings with constant charge voltage limit to predict the retained capacity and End of Discharge Voltage (EODV). To extract firm conclusion and distinguish the capability of ANN method, the predicted values are compared with experimental result by statistical method and Bland Altman plot.

  16. Three Canted Radiator Panels to Provide Adequate Cooling for Instruments on Slewing Spacecraft in LEO

    Science.gov (United States)

    Choi, Michael K.

    2012-01-01

    Certain free-flying spacecraft in low Earth orbit (LEO) or payloads on the International Space Station (ISS) are required to slew to point the telescopes at targets. Instrument detectors and electronics require cooling. Traditionally a planar thermal radiator is used. The temperature of such a radiator varies significantly when the spacecraft slews because its view factors to space vary significantly. Also for payloads on the ISS, solar impingement on the radiator is possible. These thermal adversities could lead to inadequate cooling for the instrument. This paper presents a novel thermal design concept that utilizes three canted radiator panels to mitigate this problem. It increases the overall radiator view factor to cold space and reduces the overall solar or albedo flux absorbed per unit area of the radiator.

  17. Óleo residual de frituras na alimentação de cordeiros

    OpenAIRE

    Eduardo Lucas Terra Peixoto

    2014-01-01

    Objetivou-se avaliar os efeitos dos teores de inclusão de óleo residual de frituras (ORF) na alimentação, desempenho e características de carcaça e qualidade da carne de ovinos em confinamento. Foram avaliados os níveis de 0; 20; 40; 60 e 80 g kg-1 (base da MS total da ração) de inclusão de ORF às dietas. As dietas foram formuladas para serem isoprotéicas com relação volumoso: concentrado de 60:40, tendo como fonte volumosa silagem de sorgo. No primeiro e segundo artigo foram utilizados cinco...

  18. A Handover Strategy in the LEO Satellite-Based Constellation Networks with ISLs

    Institute of Scientific and Technical Information of China (English)

    LIU Gang; GOU Dingyong; WU Shiqi

    2003-01-01

    A new handover strategy named minimal-hops handover(MHH) strategy for the low earth orbit(LEO) satellite constellations networks equipped with inter-satellite links(ISLs) is proposed.MHH strategy, which is based on the hops of the end-to-end connection paths and makes good use of the regularity of the constellation network topology, can appropriately combine the handover procedure with routing and efficiently solve the inter-satellite handover issue. Moreover, MHH strategy can provide quality of services( QoS) guarantees to some extent. The system performances of the MHH strategy, such as time propagation delay and handover frequency, are evaluated and compared with that of other previous strategies. The simulation results show that MHH strategy performs better than other previous handover strategies.

  19. Real-time kinematic positioning of LEO satellites using a single-frequency GPS receiver

    CERN Document Server

    Chen, Pei; Sun, Xiucong

    2016-01-01

    Due to their low cost and low power consumption, single-frequency GPS receivers are considered suitable for low-cost space applications such as small satellite missions. Recently, requirements have emerged for real-time accurate orbit determination at sub-meter level in order to carry out onboard geocoding of high-resolution imagery, open-loop operation of altimeters and radio occultation. This study proposes an improved real-time kinematic positioning method for LEO satellites using single-frequency receivers. The C/A code and L1 phase are combined to eliminate ionospheric effects. The epoch-differenced carrier phase measurements are utilized to acquire receiver position changes which are further used to smooth the absolute positions. A kinematic Kalman filter is developed to implement kinematic orbit determination. Actual flight data from China small satellite SJ-9A are used to test the navigation performance. Results show that the proposed method outperforms traditional kinematic positioning method in term...

  20. The Making of a Hemispheric Intellectual-Statesman: Leo S. Rowe in Argentina (1906–1919

    Directory of Open Access Journals (Sweden)

    Ricardo D. Salvatore

    2010-03-01

    Full Text Available

    Leo S. Rowe, before becoming director of the Pan-American Union, came to Argentina to gather information, connect with local intellectuals, and disseminate the basic ideas of an emerging inter-American system of cultural and intellectual cooperation that would be the backbone of Pan-Americanism. This paper deals with the interaction and communication between the Hemispheric Intellectual-Statesman and its local counterparts, focusing on the dynamic of the imperial hegemonic process. Argentine intellectuals failed to accept Rowe’s progressive ideas about modern corporations, government by public opinion, and social reform. But they were quite ready to entertain ideas of inter-American cooperation with the powerful Northern Neighbor, vindicating at the same time their affinity with and belonging to “European culture.”

  1. Performance Bounds of DPSK and OOK for Low Elevation Optical LEO Downlinks

    Directory of Open Access Journals (Sweden)

    H. Henniger

    2010-12-01

    Full Text Available Optical wireless LEO downlinks are seen as an emerging solution to increase available bandwidth to multigigabits per second. One of the biggest challenges is the impact of the atmosphere on the optical signal. The atmosphere causes time-varying link degradation due to index of refraction turbulence, especially at low elevation angles. Since the influence of the turbulence for low elevation downlinks is hardly investigated we perform numerical propagation simulations in order to achieve reliable received signal statistics. These results are further utilized to evaluate performance bounds of optical wireless systems from an information theory perspective. We focus on the two most common optical wireless systems, i.e. NRZ-DPSK and NRZ-OOK. This work shows that under low elevation angles acceptable quality of service can only be reached with high code rates.

  2. ALFALFA and WSRT Imaging of Extended HI Features in the Leo Cloud of Galaxies

    CERN Document Server

    Leisman, Lukas; Giovanelli, Riccardo; Józsa, Gyula; Adams, Elizabeth A K; Hess, Kelley M

    2016-01-01

    We present ALFALFA HI observations of a well studied region of the Leo Cloud, which includes the NGC 3227 group and the NGC 3190 group. We detect optically dark HI tails and plumes with extents potentially exceeding 600 kpc, well beyond the field of view of previous observations. These HI features contain approximately 40% of the total HI mass in the NGC~3227 group and 10% in the NGC~3190 group. We also present WSRT maps which show the complex morphology of the extended emission in the NGC~3227 group. We comment on previously proposed models of the interactions in these groups and the implications for the scale of group processing through interactions. Motivated by the extent of the HI plumes, we place the HI observations in the context of the larger loose group, demonstrating the need for future sensitive, wide field HI surveys to understand the role of group processing in galaxy evolution.

  3. Íleo pós-cirúrgico equino e o seu tratamento

    OpenAIRE

    Falcão, Slavador de Noronha de Alarcão

    2008-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária Com este estudo pretendeu-se fazer uma revisão acerca das causas e do que se sabe da fisiopatologia do íleo pós-cirúrgico equino e as suas possíveis opções de tratamento. Este estudo foi baseado na revisão bibliográfica de artigos científicos e completada com um caso clínico observado durante o estágio na universidade de Gent. O objectivo deste trabalho foi fazer uma revisão da anatomia e fisiologia do tracto gastrointestinal equ...

  4. Core-based Shared Tree Multicast Routing Algorithms for LEO Satellite IP Networks

    Institute of Scientific and Technical Information of China (English)

    Cheng Lianzhen; Zhang Jun; Liu Kai

    2007-01-01

    A new core-based shared tree algorithm, viz core-cluster combination-based shared tree (CCST) algorithm and the weighted version (i.e. w-CCST algorithm) are proposed in order to resolve the channel resources waste problem in typical source-based multicast routing algorithms in low earth orbit (LEO) satellite IP networks. The CCST algorithm includes the dynamic approximate center (DAC)core selection method and the core-cluster combination multicast route construction scheme. Without complicated onboard computation,the DAC method is uniquely developed for highly dynamic networks of periodical and regular movement. The core-cluster combination method takes core node as the initial core-cluster, and expands it stepwise to construct an entire multicast tree at the lowest tree cost by a shortest path scheme between the newly-generated core-cluster and surplus group members, which results in great bandwidth utilization.Moreover, the w-CCST algorithm is able to strike a balance between performance of tree cost and that of end-to-end propagation delay by adjusting the weighted factor to meet strict end-to-end delay requirements of some real-time multicast services at the expense of a slight increase in tree cost. Finally, performance comparison is conducted between the proposed algorithms and typical algorithms in LEO satellite IP networks. Simulation results show that the CCST algorithm significantly decreases the average tree cost against to the others, and also the average end-to-end propagation delay of w-CCST algorithm is lower than that of the CCST algorithm.

  5. Actividad anticaries de una crema dental con propóleos

    Directory of Open Access Journals (Sweden)

    Estela Gispert Abreu

    2000-12-01

    Full Text Available Por muestreo aleatorio simple se seleccionaron 50 escolares con antecedentes de alta infección por Streptococcus mutans, para verificar la actividad anticaries de una crema dental que contiene 0,8 de extracto de propóleo blando. Se perdieron del estudio a 7 escolares por inasistencia y traslados. Se crearon 2 grupos: uno control (n=19 que se cepilló con una crema dental placebo y otro tratamiento (n=24 que se cepilló con la crema dental de propóleo. Entre ambos grupos no había diferencia significativa en el índice de caries COP-D ni en el porcentaje de afectados. Luego de los 10 ciclos de cepillado durante 18 meses, dentro del grupo tratamiento se redujo significativamente en índice de caries y el porcentaje de afectados (Q = p50 students with history of high infection caused by Streptococcus mutans were selected by simple random sampling aimed at verifying the anticaries activity of a tooth paste containing 0.8 of soft propolis extract. 7 students did not conclude the study due to absences and transfers. 2 groups were created: a control group (n = 19 that brushed its teeth with a placebo tooth paste and the other under treatment (n = 24 that used a tooth paste with propolis. There was no significant difference between both groups as regards the COP-D caries index and the percentage of affection. A significant reduction of the caries index and of the percentage of affected individuals (Q = p

  6. L'illuminismo esoterico religioso medievale: Leo Strauss interprete di al-Farabi

    Directory of Open Access Journals (Sweden)

    Federico Stella

    2016-02-01

    Full Text Available Lo scopo di questo articolo è di mostrare come Leo Strauss usi la parola esoterico riguardo alla filosofia islamica ed in particolare ad al-Fārābī. La parola esoterico è usata da Strauss in due differenti modi. Nel primo modo, Strauss usa la parola per spiegare la differenza tra opere popolari (essoterici e opere esoteriche, le quali contengono il reale pensiero del filosofo. Il secondo modo è il più importante e il meno studiato. In questo significato esoterico è una metodologia di studio e di spiegazione della filosofia. L’articolo si concentra specialmente su questo secondo significato della parola esoterico e sul ruolo di questa parola per comprendere meglio la visione socio-politica della filosofia di al-Fārābī The aim of this article is to show how Leo Strauss uses the word esoteric about the Islamic philosophy, and in particular about al-Fārābī. The word esoteric is used by Strauss in two different ways. In the first way, Strauss uses the word to explain the difference between the popular (exoteric works of al-Fārābī, and the esoteric works, which contain the real thought of the philosopher. The second way is the most important and the least studied. In this meaning esoteric is a methodology to study and explain philosophy. The article focuses especially on this second meaning of the word esoteric and on the role of this word to better understand the political and social view of al-Fārābī’s philosophy.

  7. A new concept for high-cycle-life LEO: Rechargeable MnO2-hydrogen

    Science.gov (United States)

    Appleby, A. John; Dhar, Y. J.; Murphy, O. J.; Srinivasan, Supramaniam

    1989-01-01

    The nickel-hydrogen secondary battery system is now the one of choice for use in GEO satellites. It offers superior energy density to that of nickel-cadmium, with a lifetime that is at least comparable in terms of both cycle life and overall operating life. While the number of deep cycles required for GEO use is small, LEO satellites with long lifetimes (5 to 10 years) will require secondary battery systems allowing 30,000 to 60,000 useful cycles which are characterized by an approximately 2C charge rate and C average discharge rate. Recent work has shown that birnessite MnO2 doped with bismuth oxide can be cycled at very high rates (6C) over a very large number of cycles (thousands) at depths-of-discharge in the 85 to 90 percent range, based on two electrons, which discharge at the same potential in a flat plateau. The potential is about 0.7 V vs. hydrogen, with a cut-off at 0.6 V. At first sight, this low voltage would seem to be a disadvantage, since the theoretical energy density will be low. However, it permits the use of lightweight materials that are immune from corrosion at the positive. The high utilization and low equivalent weight of the active material, together with the use of teflon-bonded graphite for current collection, result in very light positives, especially when these are compared with those in a derated nickel-hydrogen system. In addition, the weight of the pressure vessel falls somewhat, since the dead volume is lower. Calculations show that a total system will have 2.5 times the Ah capacity of a derated nickel-hydrogen LEO battery, so that the energy density, based on 1.2 V for nickel-hydrogen and 0.7 V for MnO2-hydrogen, will be 45 percent higher for comparable cycling performance.

  8. LA ECO-EFICACIA DE LA PLATAFORMA LOGÍSTICA DE PETRÓLEO EN CUBA

    Directory of Open Access Journals (Sweden)

    José Antonio Acevedo Suárez

    2003-04-01

    Full Text Available

    La perspectiva integradora de la gestión ambiental proactiva con las decisiones básicas del sistema de combustible cubano se considera una oportunidad rentable y efectiva. En consecuencia, la plataforma logística de petróleo como modelo para la innovación tecnológica en la gestión de la distribución debe demostrar la compatibilidad con ambas estrategias, permitiendo así obtener las oportunidades ambientales mediante los procedimientos para el desarrollo del modelo. Además se seleccionan los medidores del desempeño ambiental para la cuantificación del efecto sobre la carga ambiental. El modelo plataforma logística de petróleo asegura la compatibilidad con la gestión ambiental proactiva a través de diferentes etapas de desarrollo, que proporcionan un conducto natural para integrar las preocupaciones ambientales de las actividades logísticas con la cadena de suministro del canal de distribución. También se identifican los indicadores de eco-eficacia como la forma más generalizadora para medir el desempeño ambiental en el ámbito empresarial, demostrando con su aplicación un uso más racional de la energía, los materiales y el agua por metros cúbicos de combustibles vendidos.

  9. Essential oils for rust control on coffee plants Óleos essenciais no controle da ferrugem em cafeeiro

    Directory of Open Access Journals (Sweden)

    Ricardo Borges Pereira

    2012-02-01

    Full Text Available Rust is considered the most important disease in coffee because it causes severe defoliation in plants and, consequently, reduction in productivity. This study evaluated the in vitro effect of essential oils of cinnamon, citronella, lemongrass, clove, tea tree, thyme, neem and eucalyptus on the germination of urediniospores of Hemileia vastatrix; the effectiveness of these oils to control rust on seedlings of coffee cultivars Catucaí 2SL, Catuaí IAC 62 and Mundo Novo 379/19 in the greenhouse; and the effect of more promising oils on urediniospores of H. vastatrix by transmission electron microscopy (TEM. All the essential oils inhibited the germination of urediniospores with increasing concentrations. All oils promoted partial control of the disease in the greenhouse. However, the oils of thyme, clove and citronella, at a concentration of 1000 µL L-1, were most effective in controlling the disease on cultivars Catucaí 2SL, Catuaí IAC 62 and Mundo Novo 379/19, respectively. The images generated in TEM showed that urediniospores exposed to oils of clove, citronella and thyme promoted cellular disorganization and cytoplasmic vacuolization, which was more pronounced in urediniospores exposed to citronella oil. The oils of thyme, clove and citronella are promising for the control of rust in coffee.A ferrugem é considerada a doença de maior importância no cafeeiro, pois causa acentuada desfolha nas plantas e, consequentemente, redução na produtividade. Este trabalho avaliou o efeito in vitro de óleos essenciais de canela, citronela, capim-limão, cravo-da-índia, árvore-de-chá, tomilho, nim e eucalipto na germinação de urediniósporos de Hemileia vastatrix; a eficácia desses óleos no controle da ferrugem em mudas de cafeeiro das cultivares Catucaí 2SL, Catuaí IAC 62 e Mundo Novo 379/19 em casa de vegetação; e o efeito dos óleos mais promissores sobre urediniósporos de H. vastatrix por meio de microscopia eletrônica de transmiss

  10. LEO&GEO双层卫星网络的动态路由技术%Dynamic routing technique based on LEO&GEO double-layered satellite network

    Institute of Scientific and Technical Information of China (English)

    姚晔; 梁旭文

    2013-01-01

    基于低地球轨道和静止地球轨道(low Earth orbit & geo-synchronous Earth orbit,LEO & GEO)双层卫星网络结构,对其覆盖特性和星间链路(inter-satellite-link,ISL)特性进行了仿真分析.提出了分层分簇的管理方法,只有主簇头与GEO卫星有连接关系,简化了互联关系的复杂性.在该卫星组网结构中,利用星座网络拓扑的特点,提出一种负载均衡的动态路由算法,综合考虑了路径时延和ISL链路负载.与单层卫星网络相比,双层卫星网络可以更加均匀地分配通信量,仅在低层LEO卫星路由跳数超出一定阈值或者卫星网络链路利用率超过某个门限范围时,才利用上层GEO卫星进行中转传输,仿真结果表明,所提路由算法可以实现更低的时延、延迟抖动以及更优的服务质量性能.

  11. Alfalfa discovery of the nearby gas-rich dwarf galaxy LEO P. V. Neutral gas dynamics and kinematics

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein-Cooper, Elijah Z.; Pardy, Stephen A. [Department of Astronomy, University of Wisconsin, 475 N Charter Street, Madison, WI 53706 (United States); Cannon, John M., E-mail: ezbc@astro.wisc.edu, E-mail: spardy@astro.wisc.edu, E-mail: jcannon@macalester.edu [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); and others

    2014-08-01

    We present new H I spectral line imaging of the extremely metal-poor, star-forming dwarf irregular galaxy Leo P. Our H I images probe the global neutral gas properties and the local conditions of the interstellar medium (ISM). The H I morphology is slightly elongated along the optical major axis. We do not find obvious signatures of interaction or infalling gas at large spatial scales. The neutral gas disk shows obvious rotation, although the velocity dispersion is comparable to the rotation velocity. The rotation amplitude is estimated to be V {sub c} =15 ± 5 km s{sup –1}. Within the H I radius probed by these observations, the mass ratio of gas to stars is roughly 2:1, while the ratio of the total mass to the baryonic mass is ≳15:1. We use this information to place Leo P on the baryonic Tully-Fisher relation, testing the baryonic content of cosmic structures in a sparsely populated portion of parameter space that has hitherto been occupied primarily by dwarf spheroidal galaxies. We detect the signature of two temperature components in the neutral ISM of Leo P; the cold and warm components have characteristic velocity widths of 4.2 ± 0.9 km s{sup –1} and 10.1 ± 1.2 km s{sup –1}, corresponding to kinetic temperature upper limits of ∼1100 K and ∼6200 K, respectively. The cold H I component is unresolved at a physical resolution of 200 pc. The highest H I surface densities are observed in close physical proximity to the single H II region. A comparison of the neutral gas properties of Leo P with other extremely metal-deficient (XMD) galaxies reveals that Leo P has the lowest neutral gas mass of any known XMD, and that the dynamical mass of Leo P is more than two orders of magnitude smaller than any known XMD with comparable metallicity.

  12. PRODUTOS DE EMULSÃO (FIAMBRES ELABORADOS COM CARNE DE POEDEIRAS LEVES (LEGHORN DE DESCARTE E ÓLEOS VEGETAIS

    Directory of Open Access Journals (Sweden)

    Nardin Tânia Regina Fiore

    1999-01-01

    Full Text Available Foram elaborados fiambres (emulsões curados e defumados com carne de poedeiras leves e óleos vegetais, e foi feita a sua comparação com produto semelhante, obtido com carne de frangos de corte. Na desossa manual dos cortes, obteve-se um rendimento médio de 14,73% para peito, 14,91% para pernas e coxas e 2,46% para as coxinhas das asas, em relação ao peso da carcaça (média de 1195,81g. A carne mista foi obtida a partir de 14,73% de carne branca (peito e 17,37% de carne escura (pernas e coxas e coxinhas das asas. O rendimento final na obtenção do produto foi de 113,50%, em relação à carne mista; em relação à carcaça congelada, de 34,34%. Quanto à composição química, os produtos apresentaram, em média, 64,76% de umidade, 13,91% de proteína, 16,62% de lipídios, 3,00% de cinzas, pH 6,21. O rendimento foi de 94,96%, após o processamento térmico e resfriamento. Os fiambres foram submetidos à análise sensorial. Quanto ao sabor, os produtos elaborados com carne de poedeira e óleo de soja foram superiores ao produto controle e não houve diferença significativa quando elaborados com óleo de milho. Apresentaram-se mais macios os elaborados com carne de frango e óleo de soja, em relação à carne de galinha. Para a avaliação de suculência, não ocorreram diferenças significativas. A cor dos fiambres elaborados com carne de poedeira foi mais atrativa que a carne dos produtos elaborados com carne de frango. Quanto à qualidade global, os fiambres elaborados com carne de poedeira e óleo de soja foram os preferidos pelos provadores, em relação à carne de frango com o mesmo óleo.

  13. Atividade inseticida do óleo essencial de Hyptis marrubioides no controle de Zabrotes subfasciatus (Coleoptera, Chrysomelidae, Bruchinae

    Directory of Open Access Journals (Sweden)

    Marcelo Barboza de Mello

    2014-02-01

    Full Text Available Sabe-se que uma grande porcentagem da produção e do armazenamento dos grãos de feijão é perdida pelo consumo de insetos. Este trabalho teve como objetivo avaliar a atividade inseticida do óleo essencial de Hyptis marrubioides no controle de Zabrotes subfasciatus. A extração do óleo essencial foi realizada pelo método de hidrodestilação em aparelho de Clevenger, por uma hora e meia e o ensaio biológico foi conduzido no Laboratório de Microscopia/IFSULDEMINAS, Campus Muzambinho. O delineamento experimental utilizado foi inteiramente casualizado, constituído de cinco concentrações de óleo essencial (0,0; 6,25%; 12,5%; 25% e 50%, com quatro repetições contendo um casal de Z. subfasciatus por repetição. Realizou-se o teste de mortalidade e inibição de oviposição. Utilizou-se três grãos de feijão tratados com 5 microlitros (μL de solução e três não tratados, caracterizando assim um teste com chance de escolha. Como controle, utilizou-se 100 μL de álcool 70%. Após a aplicação dos tratamentos, observou-se a reação dos indivíduos de Z. subfasciatus, evidenciando que os Tempos Letais (TL diminuem conforme há um aumento e contato direto dos insetos com as concentrações do óleo essencial de H. marrubioides. A aplicação do óleo essencial foi bastante efetiva, pois ocorreu mortalidade total dos insetos adultos e nenhuma oviposição. O intervalo de tempo de 28 minutos foi suficiente para provocar mortalidade de todos os indivíduos. Foi possível observar que o óleo essencial de H. marrubioides possui efeito inseticida sobre Z. subfasciatus, podendo auxiliar no manejo integrado de Z. subfasciatus em feijão armazenado.

  14. Study of geometric characteristics of inter-satellite links between LEO layer and MEO layer in LEO/MEO satellite constellation%双层卫星星座层间链路几何参数特性研究

    Institute of Scientific and Technical Information of China (English)

    王克锋; 赵洪利

    2006-01-01

    LEO/MEO双层卫星星座是现代卫星通信系统星座研究的热点.运用理论分析的方法,对LEO/MEO双层卫星星座层间链路的链路距离、仰角、方位角等几何参数进行了研究,给出了各自的计算公式,并进行仿真分析.通过仿真发现,层间链路几何参数变化的突出特点是变化范围大、变化剧烈且周期性不明显.

  15. Óleo de Soja, Óleo Ácido de Soja e Sebo Bovino Como Fontes de Gordura em Rações de Frangos de Corte

    OpenAIRE

    JB Gaiotto; JFM Menten; Racanicci AMC; MC Iafigliola

    2000-01-01

    O experimento avaliou o desempenho de frangos de corte suplementados em 4% na ração com três fontes de gordura: óleo ácido de soja (OAS4) e sebo bovino (SEBO4), óleo de soja (SOJA4) e misturas de 2% entre estas: (OAS2/SEBO2), (OAS2/SOJA2) e (SOJA2/SEBO2). Foram utilizados blocos casualizados, com 6 tratamentos, 6 repetições e 40 aves por parcela. Foram avaliadas as variáveis: consumo de ração (CR), ganho de peso (GP), peso vivo (PV), conversão alimentar (CA), fator de produção (FP) e viabilid...

  16. Avaliação de efeito antifúngico de óleos essenciais por encapsulamento em ciclodextrina : potencial de aplicação e efeitos de tratamento em pintura a óleo

    OpenAIRE

    Quinta, Maria Augusta de Magalhães Sarmento Albuquerque da

    2016-01-01

    A biodeterioração é um dos grandes factores de degradação de obras de arte, em particular por microorganismos como fungos filamentosos em variadas técnicas de pintura, incluindo pintura a óleo sobre tela. Esta dissertação teve como objectivo a realização de testes in vitro de inibição de crescimento de estirpes de fungos dos géneros Aspergillus sp., Penicillium sp. e Alternaria sp, através da volatilização de compostos antifúngicos de óleos essenciais de alfazema, sálvia e m...

  17. LEO 1.0. An assistant software for maintenance of corroded reinforced concrete structures; LEO 1.0. Logiciel d`aide l`expertise des ouvrages en beton arme corrodes

    Energy Technology Data Exchange (ETDEWEB)

    Gerard, B.; Petre-Lazar, I

    1998-04-01

    The reinforced concrete structures capacity to fulfill the users requirements decreases in time and a constant preoccupation for the maintenance is required at EDF. In order to ease up the site investigations, a computer program - LEO - is developed. Its general layout is proposed in this document. LEO 1.0 is developed to be applied to corroded reinforced concrete structures. A simplified model based on the main mechanisms of the steel corrosion in concrete has been developed. It can quantify the influence of the reinforcement corrosion on the structure performances. A probabilistic calculus which takes into account the variability of the input data (material properties, environment, etc.) was also performed using PROBAN computer code. This type of analysis quantifies the time evolution of the structure (incubation, initiation, propagation, collapse). (author) 9 refs.

  18. Aislamiento y selección de una cepa bacteriana degradadora de hidrocarburos a partir de suelos contaminados con petróleo

    Directory of Open Access Journals (Sweden)

    Rosa María Pérez Silva

    2008-01-01

    Full Text Available El conocimiento científico acerca del papel que desempeñan los microorganismos en el tratamiento de agentes contaminantes del medio ambiente como el petróleo, es esencial para prevenir y controlar los daños que puedan ocasionar los derrames o fugas de estos contaminantes. La degradación de petróleo es un proceso que puede ocurrir de forma natural por los microorganismos nativos de las zonas contaminadas aprovechando sus rutas metabólicas. Por esta razón, en estos momentos se prevé que los microorganismos pueden ofrecer esta posibilidad en tecnologías basadas en el uso de estos en la remediación de la contaminación ambiental por petróleo y sus derivados. En el presente trabajo, se estudió la biodegradación de petróleo por cepas aisladas de suelos contaminados con petróleo, mediante un aislamiento realizado por enriquecimiento secuencial utilizando petróleo Mesa 30/Puerto escondido (80 : 20 como única fuente de carbono y energía. Se aislaron 9 cepas bacterianas, cinco Gram negativas y cuatro Gram positivas, que fueron identificadas según el Manual Bergey's, 1994. Las pruebas bioquímicas evaluadas confirmaron que las cepas aisladas AT14, AT15, AT16, AT17 y AT18 corresponden a Pseudomonas aeruginosa. En este estudio, se seleccionó la cepa Pseudomonas aeruginosa AT18, por mostrar mayor crecimiento sobre petróleo como única fuente de carbono y energía al obtenerse 1,83 g/L de biomasa celular, lo que representa un 57 % de biodegradación de petróleo.

  19. Uso de óleo essencial de orégano, salinomicina e bacitracina de zinco na dieta de frangos de corte

    Directory of Open Access Journals (Sweden)

    Patricia Maria Meneghetti Pulici

    2014-09-01

    Full Text Available O presente trabalho teve como objetivo avaliar dietas com óleo essencial de orégano, associado ou não com salinomicina, como alternativa à bacitracina de zinco sobre o desempenho zootécnico de frangos de corte. Foram utilizados 600 pintos de um dia de idade, machos, da linhagem Cobb® 500, criados até 42 dias de idade em boxes com cama de casca de arroz providos de comedouros tubulares e bebedouros nipple. O delineamento foi inteiramente casualizado, com seis dietas e 10 repetições de 10 aves cada. As dietas experimentais à base de milho e farelo de soja foram: controle positivo – antibiótico (bacitracina de zinco + 0,05% de anticoccidiano (salinomicina, controle negativo – dieta basal (DB sem aditivos, DB + 0,05% de salinomicina e 0,03% de óleo essencial de orégano (Orego-Stim®, DB + 0,03% de óleo essencial de orégano, DB + 0,05% de salinomicina e 0,05% de óleo essencial de orégano, DB + 0,05% de óleo essencial de orégano. Não foi encontrado efeito da utilização do óleo de orégano até 21 dias no desempenho das aves. Nos demais períodos, aos 35 e 42 dias, o desempenho das aves tratadas com 0,03% de óleo essencial de orégano + salinomicina apresentou resultados semelhantes ao controle positivo, levando à conclusão de que a dose de 0,03% de óleo essencial de orégano + salinomicina pode substituir a bacitracina de zinco + salinomicina em dietas para frangos de corte.

  20. Simulation of the impacts of satellite orbit parameters on the number and distribution of LEO - LEO occultation events%卫星轨道参数对LEO-LEO掩星事件数量及分布影响的模拟研究

    Institute of Scientific and Technical Information of China (English)

    杜晓勇; 符养; 薛震刚; 郭粤宁; 毛节泰

    2007-01-01

    文章对LEO-LEO卫星掩星事件的特性进行了深入讨论,通过仿真计算定量讨论了轨道参数对掩星事件次数及分布的影响.结果指出:1)对一年掩星事件数量及其纬度分布影响大的轨道参数依次是轨道倾角、轨道高度、升交点赤经和近地点角距;而这些参数对一年掩星事件的经度分布影响都不大;2)发射卫星和接收卫星倾角之间的相互关系对掩星事件数量和纬度分布影响最大,两卫星倾角接近互补时掩星事件最多,两颗LEO卫星中与90°相差较大的倾角决定了LEO-LEO掩星事件的纬度分布范围;3)发射卫星和接收卫星处于同一轨道高度时,LEO-LEO掩星事件数取得极大值,发射卫星和接收卫星都采用600 km的轨道高度,一年LEO-LEO掩星事件数最多;4)发射卫星和接收卫星升交点赤经(RAAN)的相互关系对LEO-LEO掩星事件数量影响很大,发射卫星和接收卫星升交点赤经之差为120°或240°时掩星事件数量最多,RAAN对掩星事件纬度和经度分布影响不大;5)近地点角距对掩星事件数量和分布影响都不大.该研究结果对LEO-LEO掩星探测卫星的轨道设计有一定的参考作用.

  1. Efeito de óleo essencial de laranja associados a fungicidas no controle de doenças foliares do trigo

    Directory of Open Access Journals (Sweden)

    Cezar Coradini

    2016-03-01

    Full Text Available RESUMO Foi conduzido um experimento em campo na safra de 2012 com o objetivo de avaliar a contribuição do óleo essencial de laranja na performance dos fungicidas visando o controle de doenças foliares do trigo. O delineamento experimental foi o de blocos ao acaso em arranjo fatorial (3x5 + 1, com quatro repetições. O fator A foi composto pelos fungicidas (dose do produto comercial epoxiconazol (0,75L ha-1, piraclostrobina (0,80L ha-1 e epoxiconazol+piraclostrobina (0,75L ha-1 e o fator B pelos adjuvantes (doses óleo mineral (500mL ha-1 e óleo essencial de laranja (0, 50, 100 e 150mL ha-1. O tratamento adicional compreendeu-se pela testemunha (água. O controle de manchas foliares na folha bandeira foi mais eficaz com a aplicação de epoxiconazol e de epoxiconazol+piraclostrobina independentemente do adjuvante usado ser óleo mineral ou óleo essencial de laranja, enquanto que os adjuvantes testados não interferiram no controle da ferrugem. O peso do hectolitro, massa de mil grãos e a produtividade do trigo não foram afetados negativamente pelas diferentes concentrações do óleo essencial de laranja.

  2. MODELAGEM TERMODINÂMICA DO FRACIONAMENTO DO ÓLEO DE MANTEIGA COM FLUIDOS SUPERCRÍTICOS

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    Guilherme B. M. NEVES

    1997-12-01

    Full Text Available O fracionamento do óleo de manteiga em frações de propriedades físicas e químicas diferentes mostra-se uma possível solução para o problema do excedente de óleo de manteiga no mercado internacional, despertando interesse em seu estudo. Com o objetivo de se modelar o equilíbrio de fases neste processo, foi feito um agrupamento dos 1331 triglicerídeos presentes no óleo de manteiga em 14 famílias. Assim, os componentes de uma mesma família possuem um comportamento semelhante quando expostos ao CO2 Supercrítico (CO2 SC. A seguir, utilizando a Equação de Peng-Robinson, realizou-se o cálculo do equilíbrio de fases no sistema óleo de manteiga/CO2, sendo o óleo de manteiga representado por uma mistura de 14 componentes hipotéticos, as famílias. Foram desenvolvidas correlações para a temperatura e pressão críticas e parâmetros de interação binária das famílias. O modelo foi capaz de correlacionar dados obtidos da literatura. As predições do equilíbrio de fases estão em excelente concordância com os dados obtidos pelos autores deste trabalho para os sistemas de óleo de manteiga/CO2. O procedimento mostrado aqui aplica-se não só ao dióxido de carbono supercrítico mas também a outros fluidos ou misturas de fluidos supercríticos, e também não somente ao óleo de manteiga, mas a todos os óleos/gorduras cuja constituição principal sejam triglicerídeos.Fractionation of butter oil into fractions with different physical and chemical properties is a possible solution for the problem of the excess of butter oil in the international market. With the objective of modeling the phase equilibria, the 1331 triglycerides were grouped into 14 families according to the number of carbons. Components belonging to the same family are considered to exhibit similar behavior when exposed to supercritical carbon dioxide (SC CO2. Using the Peng-Robinson equation of state, phase equilibrium calculations were performed for the butter

  3. Caracterização química do óleo essencial de Hypericum brasiliense Choisy

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    E.S. Carvalho

    2003-01-01

    Full Text Available Hypericum brasiliense Choisy, planta da família Guttiferae, ocorre principalmente nas regiões Sudeste e Sul do Brasil. Em trabalhos anteriores foram isolados e identificados nesta espécie, dentre outras classes de compostos, xantonas, floroglucinóis e flavonóides. Apesar da presença de óleos essenciais ser uma característica do gênero, ainda não há registros na literatura da composição química do óleo essencial desta espécie. Neste trabalho foi realizado o estudo químico da fração volátil de H. brasiliense visando identificar e quantificar as substâncias químicas presentes através da cromatografia em fase gasosa acoplada a espectrômetro de massas equipado com banco de dados.

  4. An Updated Zero Boil-Off Cryogenic Propellant Storage Analysis Applied to Upper Stages or Depots in a LEO Environment

    Science.gov (United States)

    Plachta, David; Kittel, Peter

    2003-01-01

    Previous efforts have shown the analytical benefits of zero boil-off (ZBO) cryogenic propellant storage in launch vehicle upper stages of Mars transfer vehicles for conceptual Mars Missions. However, recent NASA mission investigations have looked at a different and broad array of missions, including a variety of orbit transfer vehicle (OTV) propulsion concepts, some requiring cryogenic storage. For many of the missions, this vehicle will remain for long periods (greater than one week) in low earth orbit (LEO), a relatively warm thermal environment. Under this environment, and with an array of tank sizes and propellants, the performance of a ZBO cryogenic storage system is predicted and compared with a traditional, passive-only storage concept. The results show mass savings over traditional, passive-only cryogenic storage when mission durations are less than one week in LEO for oxygen, two weeks for methane, and roughly 2 months for LH2. Cryogenic xenon saves mass over passive storage almost immediately.

  5. Impedance measurements on a spiral-wound nickel/metal hydride cell cycled in a simulated Leo orbit

    Science.gov (United States)

    Reid, Margaret A.

    1993-01-01

    A spiral-wound size C cell was cycled at 25 C in a low earth orbit (LEO) regime at 50 percent depth of discharge (DOD) with approximately five percent over-charge. The nominal capacity was 3.5 AH. The cell was cycled for 2000 cycles. Capacity checks and impedance measurements over the complete range of state of charge were made upon receipt and after 500, 1000, and 2000 cycles. The capacity of the cell was essentially unchanged until after the impedance measurements at 2000 cycles. Only small changes in the impedance parameters were observed, but there was somewhat more scatter in the data after 2000 cycles. When the cell was returned to LEO cycling after 2000 cycles, only 38 percent of the capacity could be obtained. It is believed that the cell failed because of an equipment failure at the end of the final impedance measurements which allowed an over-discharge.

  6. Mission Analysis for LEO Microwave Power-Beaming Station in Orbital Launch of Microwave Lightcraft

    Science.gov (United States)

    Myrabo, L. N.; Dickenson, T.

    2005-01-01

    A detailed mission analysis study has been performed for a 1 km diameter, rechargeable satellite solar power station (SPS) designed to boost 20m diameter, 2400 kg Micr,oWave Lightcraft (MWLC) into low earth orbit (LEO) Positioned in a 476 km daily-repeating oi.bit, the 35 GHz microwave power station is configured like a spinning, thin-film bicycle wheel covered by 30% efficient sola cells on one side and billions of solid state microwave transmitter elements on the other, At the rim of this wheel are two superconducting magnets that can stor,e 2000 G.J of energy from the 320 MW, solar array over a period of several orbits. In preparation for launch, the entire station rotates to coarsely point at the Lightcraft, and then phases up using fine-pointing information sent from a beacon on-board the Lightcraft. Upon demand, the station transmits a 10 gigawatt microwave beam to lift the MWLC from the earth surface into LEO in a flight of several minutes duration. The mission analysis study was comprised of two parts: a) Power station assessment; and b) Analysis of MWLC dynamics during the ascent to orbit including the power-beaming relationships. The power station portion addressed eight critical issues: 1) Drag force vs. station orbital altitude; 2) Solar pressure force on the station; 3) Station orbital lifetime; 4) Feasibility of geo-magnetic re-boost; 5) Beta angle (i..e., sola1 alignment) and power station effective area relationship; 6) Power station percent time in sun vs, mission elapsed time; 7) Station beta angle vs.. charge time; 8) Stresses in station structures.. The launch dynamics portion examined four issues: 1) Ascent mission/trajecto1y profile; 2) MWLC/power-station mission geometry; 3) MWLC thrust angle vs. time; 4) Power station pitch rate during power beaming. Results indicate that approximately 0 58 N of drag force acts upon the station when rotated edge-on to project the minimum frontal area of 5000 sq m. An ion engine or perhaps an electrodynamic

  7. Der Umlauf der spanischen Handschriften aus dem Antiquariat Leo Liepmannssohns in Paris und Berlin

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    Romero Naranjo, Francisco Javier

    2004-12-01

    Full Text Available One of the antique libraries most representative of the second half of the 19th century was that of Leo Liepmannssohn, with branches in Paris and Berlin. Its importance grew over time due to its auctions of many manuscripts by J. S. Bach, Handel, Mozart, Beethoven and other composers, a fact that explains how the author came across it during his investigation into the referred manuscripts. The object of this investigation is a collection of more than 300 folders that can be consulted in the Music Department in the Staatsbibliothek Preußischer Kulturbesitz in Berlin. The folders contain the annual catalogues from the antique library of Liepmannssohn (Berlin comprising the years 1866 to 1923. Each catalogue consists of a list of all the sales from the corresponding year in alphabetical order and contains, besides manuscripts, literature, musical treatises and the portraits of several composers. There are many Spanish manuscripts included in these catalogues whose distribution was so important that in 1900 Liepmannssohn published an exclusive catalogue for Spanish and Portuguese manuscripts, 291 of which the librarian had sold during that year. During the celebration of those auctions many documents, musical treatises and manuscripts, both known and unknown, were brought to light. The investigation earned out contributes to our knowledge about the works of different Spanish composers from the 16th to the 19th centuries and their distribution abroad, especially in Berlin.

    [de] Eines der repräsentativsten Antiquariate der zweiten Hälfte des XIX Jh. und des Anfangs des XX Jh. wurde von Leo Liepmannssohn in den Städten Paris und Berlin verwaltet. Durch die Versteigerung vieler Handschriften von J.S. Bach, Händel, Mozart, Beethoven und anderer Komponisten gewann das Antiquariat zusatzlich an Bedeutung. Deswegen ist es verstandlich, dass der Autor auf das Antiquariat stieß, als er Nachforschungen über den

  8. Extrato de alho e óleo vegetal no controle do míldio da videira

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    Carla Daiane Leite

    2011-06-01

    Full Text Available O objetivo deste trabalho foi verificar o efeito do extrato de alho e do óleo vegetal no controle do míldio da videira cv. Isabel (Vitis labrusca. A severidade da doença, expressa pela área abaixo da curva de progresso da doença (AACPD, e a germinação de esporângios de seu agente causal Plasmopara viticola foram as variáveis avaliadas. Os tratamentos consistiram em 0; 5; 10; 15; 20; 25 ou 30 mL L-1 de extrato de alho adicionados de 2,5 mL L-1 óleo vegetal, calda bordalesa (1:1:100 e testemunha (sem tratamento. No teste de germinação, utilizou-se mancozebe (2 g L-1 como tratamento-padrão. Em condições de campo, observou-se redução da severidade do míldio com o óleo vegetal, sendo que o extrato de alho, a partir de 20 mL L-1, potencializou tal ação biocida. A germinação dos esporângios de P. viticola variou em função do tempo de exposição ao extrato de alho, não apresentando boa eficiência quando comparada ao tratamento com calda bordalesa e mancozebe. O óleo vegetal não influenciou na germinação dos esporângios desse patógeno.

  9. Cutaneous squamous cell carcinoma presenting as a wound with discharging sinus tracts in a wild African lion (Panthera leo).

    Science.gov (United States)

    Mwase, M; Mumba, C; Square, D; Kawarai, S; Madarame, H

    2013-11-01

    A female wild African lion (Panthera leo) was presented with an 8-month history of a wound with multiple discharging sinus tracts on the left paw. Microscopical examination revealed squamous cell carcinoma (SCC). To the best of our knowledge, this is the first report of cutaneous SCC in an African lion. Cutaneous SCC presenting as discharging sinus tracts lined by neoplastic squamous cells has not been reported previously in animals.

  10. Chemistry and Kinematics of the Late-forming Dwarf Irregular Galaxies Leo A, Aquarius, and Sagittarius DIG

    Science.gov (United States)

    Kirby, Evan N.; Rizzi, Luca; Held, Enrico V.; Cohen, Judith G.; Cole, Andrew A.; Manning, Ellen M.; Skillman, Evan D.; Weisz, Daniel R.

    2017-01-01

    We present Keck/DEIMOS spectroscopy of individual stars in the relatively isolated Local Group dwarf galaxies Leo A, Aquarius, and the Sagittarius dwarf irregular galaxy. The three galaxies—but especially Leo A and Aquarius—share in common delayed star formation histories (SFHs) relative to many other isolated dwarf galaxies. The stars in all three galaxies are supported by dispersion. We found no evidence of stellar velocity structure, even for Aquarius, which has rotating H i gas. The velocity dispersions indicate that all three galaxies are dark-matter-dominated, with dark-to-baryonic mass ratios ranging from {4.4}-0.8+1.0 (SagDIG) to {9.6}-1.8+2.5 (Aquarius). Leo A and SagDIG have lower stellar metallicities than Aquarius, and they also have higher gas fractions, both of which would be expected if Aquarius were further along in its chemical evolution. The metallicity distribution of Leo A is inconsistent with a closed or leaky box model of chemical evolution, suggesting that the galaxy was pre-enriched or acquired external gas during star formation. The metallicities of stars increased steadily for all three galaxies, but possibly at different rates. The [α/Fe] ratios at a given [Fe/H] are lower than that of the Sculptor dwarf spheroidal galaxy, which indicates more extended SFHs than Sculptor, consistent with photometrically derived SFHs. Overall, the bulk kinematic and chemical properties for the late-forming dwarf galaxies do not diverge significantly from those of less delayed dwarf galaxies, including dwarf spheroidal galaxies. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

  11. Drifting plasma collection by a positive biased tether wire in LEO-like plasma conditions: current measurement and plasma diagnostic

    OpenAIRE

    Siguier, Jean-Michel; Sarrailh, Pierre; Roussel, Jean-François; Inguimbert, Virgine; Murat, Gaël; Sanmartín Losada, Juan Ramón

    2013-01-01

    BETs is a three-year project financed by the Space Program of the European Commission, aimed at developing an efficient deorbit system that could be carried on board any future satellite launched into Low Earth Orbit (LEO). The operational system involves a conductive tape-tether left bare to establish anodic contact with the ambient plasma as a giant Langmuir probe. As a part of this project, we are carrying out both numerical and experimental approaches to estimate the collected current by ...

  12. Óleo de eucalipto e Pisolithus microcarpus no crescimento de bracatinga em solo contaminado por cobre

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    Alex Dellai

    2014-09-01

    Full Text Available As áreas de mineração de cobre podem apresentar teores elevados disponíveis deste nutriente no solo afetando o desenvolvimento vegetal. O objetivo do trabalho foi avaliar o efeito do óleo essencial de eucalipto na associação ectomicorrizica com o fungo Pisolithus microcarpus em mudas de bracatinga e seu comportamento em solo contaminado por cobre. O experimento foi conduzido em delineamento inteiramente casualizado em arranjo fatorial (4 x 5 sendo quatro formas de inoculação (testemunha, óleo, fungo e óleo + fungo e cinco doses de cobre (nível natural do solo, 60, 120, 180 e 240 mg de Cu kg-1 de solo com cinco repetições. Avaliaram-se a altura de plantas (cm, diâmetro do colo (mm, massa seca da parte aérea e radicular (g, comprimento radicular (cm, área superficial específica (cm², relação altura/diâmetro do colo e índice de qualidade de Dickson. Verificou-se que a utilização de 40 μL L-1 de óleo essencial de eucalipto aumenta a altura das mudas de bracatinga em solo com adição de 180 mg de Cu kg-1 de solo. Não há efeito da inoculação de Pisolithus microcarpus no crescimento das mudas de bracatinga em solo contaminado com cobre. As doses de cobre reduzem a massa seca da parte aérea e radicular das mudas.

  13. Basic performance of BeiDou-2 navigation satellite system used in LEO satellites precise orbit determination

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    Liu Junhong

    2014-10-01

    Full Text Available The visibility for low earth orbit (LEO satellites provided by the BeiDou-2 system is analyzed and compared with the global positioning system (GPS. In addition, the spaceborne receivers’ observations are simulated by the BeiDou satellites broadcast ephemeris and LEO satellites orbits. The precise orbit determination (POD results show that the along-track component accuracy is much better over the service area than the non-service area, while the accuracy of the other two directions keeps at the same level over different areas. However, the 3-dimensional (3D accuracy over the two areas shows almost no difference. Only taking into consideration the observation noise and navigation satellite ephemeris errors, the 3D accuracy of the POD is about 30 cm. As for the precise relative orbit determination (PROD, the 3D accuracy is much better over the eastern hemisphere than that of the western hemisphere. The baseline length accuracy is 3.4 mm over the service area, and it is still better than 1 cm over the non-service area. This paper demonstrates that the BeiDou regional constellation could provide global service to LEO satellites for the POD and the PROD. Finally, the benefit of geostationary earth orbit (GEO satellites is illustrated for POD.

  14. Basic performance of BeiDou-2 navigation satellite system used in LEO satellites precise orbit determination

    Institute of Scientific and Technical Information of China (English)

    Liu Junhong; Gu Defeng; Ju Bing; Yao Jing; Duan Xiaojun; Yi Dongyun

    2014-01-01

    The visibility for low earth orbit (LEO) satellites provided by the BeiDou-2 system is analyzed and compared with the global positioning system (GPS). In addition, the spaceborne receivers’ observations are simulated by the BeiDou satellites broadcast ephemeris and LEO satel-lites orbits. The precise orbit determination (POD) results show that the along-track component accuracy is much better over the service area than the non-service area, while the accuracy of the other two directions keeps at the same level over different areas. However, the 3-dimensional (3D) accuracy over the two areas shows almost no difference. Only taking into consideration the observation noise and navigation satellite ephemeris errors, the 3D accuracy of the POD is about 30 cm. As for the precise relative orbit determination (PROD), the 3D accuracy is much better over the eastern hemisphere than that of the western hemisphere. The baseline length accuracy is 3.4 mm over the service area, and it is still better than 1 cm over the non-service area. This paper demon-strates that the BeiDou regional constellation could provide global service to LEO satellites for the POD and the PROD. Finally, the benefit of geostationary earth orbit (GEO) satellites is illustrated for POD.

  15. First Asian record of Panthera (Leo) fossilis (Mammalia, Carnivora, Felidae) in the Early Pleistocene of Western Siberia, Russia.

    Science.gov (United States)

    Sotnikova, Marina V; Foronova, Irina V

    2014-08-01

    A lion-like pantherine felid is described as Panthera (Leo) fossilis from the late Early Pleistocene sediments of the Kuznetsk Basin (Western Siberia, Russia). The find of P. fossilis first recorded in Asia considerably extends the current notion of the eastward expansion of the most ancient lions. The Siberian lion is geologically the oldest form and is dimensionally among the largest members of the group of fossil lions on the Eurasian continent. Although known by mandibular remains only, it is readily distinguished from Panthera (Leo) spelaea by a heavy built mandibular corpus with rectangular profile in the cheek teeth area, a deep, well-outlined and narrow anterior section of the masseteric fossa, and a large p4 supported by a big unreduced anterior root. The Siberian lion shares these features with the European Middle Pleistocene P. fossilis and the American Late Pleistocene P. (Leo) atrox, which suggests their close relationship. P. atrox originated from P. fossilis and was isolated in North America south of the Late Pleistocene ice sheets. This explains why the American lion has retained more primitive features than the coeval Eurasian cave lion P. (L.) spelaea.

  16. Efeitos de óleos essenciais de plantas no tempo de sono induzido por cetamina em camundongos

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    Simony Fauth

    2002-01-01

    Full Text Available Estudos anteriores mostraram que óleos essenciais voláteis obtidos de plantas potenciam o tempo de sono induzido por pentobarbital e álcool em camundongos. Cetamina é um anestésico muito utilizado em crianças, sendo conhecida por causar uma anestesia dissociativa. Seus efeitos alucinógenos podem ser reduzidos quando administrada em associação a benzodiazepínicos. O objetivo deste estudo foi determinar a influência dos óleos de Psidium guyanensis (Araçá azedo, Psidium pohlianum (Araçá doce, Psidium guajava (Araçá goiaba, Rosmarinus officinalis (Alecrim e Lippia alba (Cidreira no tempo de sono induzido por cetamina em camundongos. Os resultados indicam que o tempo de sono induzido por cetamina foi prolongado pelos óleos essenciais de Psidium guyanensis, Psidium pohlianum, Psidium guajava e Lippia Alba mostrando novas possibilidades de associação com a cetamina a fim de prolongar o seu efeito sedativo, proporcionando uma anestesia mais adequada.

  17. PROSPECÇÃO TECNOLÓGICA DE ÓLEO ESSENCIAL DE AROEIRA-DA-PRAIA (Schinus terebinthifolius Raddi.

    Directory of Open Access Journals (Sweden)

    Valéria Melo Mendonça

    2014-03-01

    Full Text Available A aroeira-da-praia (Schinusterebinthifolius Raddi. é uma espécie brasileira com grande importânciano cenário mundial por diversas características de interesse, dentre elas, oóleo essencial por seu valor fitoterápico. Com o intuito de verificarinformações sobre o uso do óleo essencial desta planta foi realizada umaprospecção em bancos de dados de pesquisa científica, tecnológica e de patentes.Existem muitos trabalhos acadêmicos sobre a aroeira-da-praia, mas poucos sobreóleo essência e número de depósito de patentes. Sendo assim, nota-se umadiscrepância entre o conhecimento acadêmico e o desenvolvimento tecnológico. Onúmero reduzido de patentes corrobora com o pouco registro de medicamentos efitoterápicos em órgãos de controle e certificação, como os Ministérios daSaúde e da Agricultura, e Vigilância Sanitária.

  18. Angiogenic activity of sucupira (Pterodon emarginatus oil = Atividade angiogênica do óleo de sucupira (Pterodon emarginatus

    Directory of Open Access Journals (Sweden)

    Araújo, Lilhian Alves de

    2015-01-01

    Full Text Available Objetivos: Avaliar a atividade angiogênica do óleo de sucupira (Pterodon emarginatus , popularmente utilizado como antirreumático, analgésico, antimicrobiano e anti-inflamatório. Métodos: Foi aplicado como modelo experimental o ensaio na membrana corioalantóidea (MCA de ovo embrionado de galinha (Gallus domesticus . Os ovos foram incubados em estufa automática com temperatura e umidade controladas durante os primeiros cinco dias. No quinto dia foi realizada uma abertura circular na base maior da casca do ovo. No 13 º dia de incubação, discos de papel de filtro contendo óleo de sucupira e as substâncias controle foram inseridos sobre vasos da MCA. Posteriormente, as MCAs foram removidas e passaram por análise e quantificação da rede vascular. Para análise estatística foi utilizado o teste não paramétrico de Kruskal-Wallis, seguido de Dunn, sendo os valores aceitáveis para diferenças significativas entre as amost ras de p 0. 05. Conclusões: O óleo da fava de sucupira (Pterodon emarginatus, nas condições deste experimento, foi responsável pela formação de novos vasos sanguíneos

  19. Pulpotomías de molares temporales en pulpas muertas con tintura de propóleos al 10%

    Directory of Open Access Journals (Sweden)

    Walkyria del Carmen González Rodríguez

    Full Text Available Se realizó un ensayo clínico fase II aleatorizado comparado en 50 niños de 4 a 10 años que presentaron molares temporales con muerte pulpar, los cuales acudieron a la Clínica Estomatológica Provincial de Santiago de Cuba entre septiembre del 2005 y septiembre del 2006, con el objetivo de demostrar la eficacia de la tintura de propóleos al 10 % en pulpotomías (necropulpotomías. Se conformaron 2 grupos de tratamientos de 26 pacientes cada uno: en el grupo A se empleó tintura de propóleos al 10 % y en el B el formocresol. Los pacientes se evaluaron a los 7, 15 y 30 días, sin observarse diferencias ni reacciones adversas. El grupo dentario más tratado fue el constituido por los segundos molares temporales inferiores, donde la tintura de propóleos al 10 % en las pulpotomías, resultó ser tan eficaz como el formocresol, por lo que se recomienda incluir en tratamientos endodónticos esta nueva terapéutica.

  20. Regime fiscal, investimento em petróleo e opções reais

    Directory of Open Access Journals (Sweden)

    Fernando Antonio Slaibe Postali

    2009-06-01

    Full Text Available O objetivo deste artigo é avaliar o impacto dos benefícios governamentais da indústria do petróleo no Brasil - royalties e Participações Especiais - na decisão de investir no desenvolvimento de reservas de petróleo. Utilizamos a metodologia de opções reais, que considera o valor das flexibilidades gerenciais no projeto de investimento. O modelo admite a opção de esperar e a opção de abandonar, no qual se simula o impacto de diferentes estruturas de alíquotas de royalties e de Participações Especiais sobre as razões preço-custo que determinam o desenvolvimento da reserva ou a saída da indústria. A partir de umexperimento deMonte Carlo, estima-se uma trajetória para o preço e para o custo operacional, comvistas a avaliar as receitas esperadas para o governo sob cada estrutura de alíquotas. Os resultados sugerem que as Participações Especiais, apesar de seu potencial arrecadatório maior, podem retrair a decisão de investir tanto quanto (ou mesmo mais que os royalties. Desta forma, a ampliação desta modalidade tributária, cuja discussão foi motivada pelas recém anunciadas descobertas do pré-sal, pode não ser uma boa iniciativa.The aimof this paper is to evaluate the impact of the Brazilian petroleumfiscal regime - royalties and special participation tax - on the decision to invest in the development of oil and gas reserves in Brazil. We use the Real Option approach, which considers the value of managerial flexibilities. The model admits the option to wait and the option to abandon. It is simulated the impact of different royalties and special participation tax rates on the threshold price-cost ratios to develop the reserve and to exit the industry. Through a Monte Carlo experiment, it is also estimated a path for both prices and costs with the purpose of assessing the expected revenues to the government under each tax rate. Results suggest that special participation tax, despite its ability to increase revenues, is

  1. Short and long term efficiencies of debris risk reduction measures: Application to a European LEO mission

    Science.gov (United States)

    Lang, T.; Kervarc, R.; Bertrand, S.; Carle, P.; Donath, T.; Destefanis, R.; Grassi, L.; Tiboldo, F.; Schäfer, F.; Kempf, S.; Gelhaus, J.

    2015-01-01

    Recent numerical studies indicate that the low Earth orbit (LEO) debris environment has reached a point such that even if no further space launches were conducted, the Earth satellite population would remain relatively constant for only the next 50 years or so. Beyond that, the debris population would begin to increase noticeably, due to the production of collisional debris (Liou and Johnson, 2008). Measures to be enforced play thus a major role to preserve an acceptable space mission risk and ensure sustainable space activities. The identification of such measures and the quantification of their efficiency over time for LEO missions is of prime concern in the decision-making process, as it has been investigated for the last few decades by the Inter-Agency Space Debris Coordination Committee (IADC). This paper addresses the final results of a generic methodology and the characteristics of a tool developed to assess the efficiency of the risk reduction measures identified for the Sentinel-1 (S1) mission. This work is performed as part of the 34-month P2-ROTECT project (Prediction, Protection & Reduction of OrbiTal Exposure to Collision Threats), funded by the European Union within the Seventh Framework Programme. Three ways of risk reduction have been investigated, both in short and long-term, namely: better satellite protection, better conjunction prediction, and cleaner environment. According to our assumptions, the S1 mission vulnerability evaluations in the long term (from 2093 to 2100) show that full compliance to the mitigation measures leads to a situation twice safer than that induced by an active debris removal of 5 objects per year in a MASTER2009 Business-As-Usual context. Because these measures have visible risk reduction effects in the long term, complementary measures with short response time are also studied. In the short term (from 2013 to 2020), a better prediction of the conjunctions is more efficient than protecting the satellite S1 itself. By

  2. ESTUDO TRIBOLÓGICO DE ÓLEOS BIODEGRADÁVEIS DE COCO E DE RÍCINO ATRAVÉS DE ENSAIOS ABRASIVOS

    Directory of Open Access Journals (Sweden)

    jaciana silva de santana

    2010-11-01

    Full Text Available Em substituição aos óleos minerais, os óleos biodegradáveis vêm proporcionando uma grande alternativa ao mercado, uma vez que o mesmo diminui os impactos ambientais. Com a finalidade de avaliar o desempenho do óleo de rícino (refinado e bruto e o óleo de coco comparando-os com os óleos minerais SAE 20W50 SJ e W40, realizaram-se ensaios tribológicos de desgaste na configuração pino-contra-cilindro de aço AISI 52100. As superfícies das amostras metálicas foram confeccionadas por torneamento e lixamento, utilizando-se lixas de diferentes granulometrias, seguidas por limpeza com banho ultrassônico e pesagem antes e após a realização dos ensaios. Os corpos-de-prova foram analisados antes dos ensaios no microscópio óptico. A dureza do aço AISI 52100 foi medida utilizando-se um durômetro Rockwell. O óleo foi caracterizado através de ensaios de densidade e tensão superficial (Souza et. al., 2007. A eficiência da ação do lubrificante foi avaliada através da taxa de desgaste calculada para as amostras utilizando-se a equação de Archard e através da microscopia eletrônica de varredura (MEV. Segundo resultados da taxa de desgaste, os óleos vegetais de rícino e coco obtiveram valores de 88,89 % e 33,33 % menores que para os óleos W40 e SAE 20W50 SJ, respectivamente. Sendo assim, os óleos vegetais possuem propriedades tribológicas equivalentes e até superiores às dos óleos minerais estudados.

  3. Design and Fabrication of DebriSat - A Representative LEO Satellite for Improvements to Standard Satellite Breakup Models

    Science.gov (United States)

    Clark, S.; Dietrich, A.; Fitz-Coy, N.; Weremeyer, M.; Liou, J.-C.

    2012-01-01

    This paper discusses the design and fabrication of DebriSat, a 50 kg satellite developed to be representative of a modern low Earth orbit satellite in terms of its components, materials used, and fabrication procedures. DebriSat will be the target of a future hypervelocity impact experiment to determine the physical characteristics of debris generated after an on-orbit collision of a modern LEO satellite. The major ground-based satellite impact experiment used by DoD and NASA in their development of satellite breakup models was SOCIT, conducted in 1992. The target used for that experiment was a Navy transit satellite (40 cm, 35 kg) fabricated in the 1960's. Modern satellites are very different in materials and construction techniques than those built 40 years ago. Therefore, there is a need to conduct a similar experiment using a modern target satellite to improve the fidelity of the satellite breakup models. To ensure that DebriSat is truly representative of typical LEO missions, a comprehensive study of historical LEO satellite designs and missions within the past 15 years for satellites ranging from 1 kg to 5000 kg was conducted. This study identified modern trends in hardware, material, and construction practices utilized in recent LEO missions. Although DebriSat is an engineering model, specific attention is placed on the quality, type, and quantity of the materials used in its fabrication to ensure the integrity of the outcome. With the exception of software, all other aspects of the satellite s design, fabrication, and assembly integration and testing will be as rigorous as that of an actual flight vehicle. For example, to simulate survivability of launch loads, DebriSat will be subjected to a vibration test. As well, the satellite will undergo thermal vacuum tests to verify that the components and overall systems meet typical environmental standards. Proper assembly and integration techniques will involve comprehensive joint analysis, including the precise

  4. Ressecção do intestino grosso e anastomose íleo-retal em suínos

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    Oliveira H.P.

    2002-01-01

    Full Text Available A anastomose íleo-retal término-terminal, após ressecção do intestino grosso, foi realizada em 13 suínos Large White x Landrace, com média de 15kg de peso e em torno de 67 dias de idade, sob anestesia pelo halotano, em circuito semifechado. A laparotomia constou de incisão na região paramediana esquerda, no sentido da bainha prepucial, seguida de incisão na linha branca. O intestino grosso foi liberado das suas relações com o intestino delgado e do mesentério até a sua posição relativa aos ligamentos laterais da bexiga. O íleo e o reto foram seccionados tão próximo quanto possível da válvula íleocecal e a 10 e 12cm do esfíncter anal, respectivamente, e as ligaduras dos vasos mesentéricos foram feitas em massa, a intervalos de 2-3cm. O intestino grosso foi removido, procedendo-se a anastomose íleo-retal, mediante sutura seromucosa, por pontos simples separados tipo Swift, com fio de seda preto n° 0, a 2-3mm das bordas, com os nós posicionados para o lume do órgão. Em suínos jovens, a anastomose íleo-retal após ressecção do intestino grosso é tecnicamente exeqüível e permite a sobrevivência dos animais por período adequado até sua utilização em pesquisas sobre digestibilidade. O material e o tipo de sutura utilizados permitiram adequada justaposição das bordas intestinais da anastomose, compensando pequenas diferenças entre os diâmetros do íleo e do reto. A remoção do intestino grosso conduziu a adaptações morfofuncionais marcantes, e a dilatação do segmento distal do intestino delgado constituiu a alteração macroscópica mais significativa. Observou-se redução no desenvolvimento e no peso corporal dos animais adaptados à nova condição fisiológica.

  5. Depth and Surface. Max Weber, Leo Strauss, and the Practical Nature of Political Philosophy.

    Directory of Open Access Journals (Sweden)

    Luciano Nosetto

    2015-12-01

    Full Text Available According to Leo Strauss, Max Weber has been the most salient proponent of modern social science, that is to say, of a value-free social science. The second chapter of Strauss’ Natural Right and History consists of a critical overview of Max Weber’s perspective and, in particular, of his attempt to build the modern social science edifice upon the ground of the distinction between facts and values. The work here delivered consists of a comment or close reading of the chapter of Strauss on Weber. The aim of this reading is to show how the Weberian distinction between facts and values dilutes the most basic skills of the man of science, leading towards a nihilistic social philosophy, and towards an absurd social science. At the same time, Strauss’ reading examines the Weberian diagnosis of modern civilization, by means of an analysis of the sociological and political figures of the specialist, the philistine, and the extremist. After an account of Strauss’ critic of Weber, this article considers the Straussian proposal of a return to political philosophy in its classical sense.

  6. Head rubbing and licking reinforce social bonds in a group of captive African lions, Panthera leo.

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    Tomoyuki Matoba

    Full Text Available Many social animals have a species-specific repertoire of affiliative behaviours that characterise individualised relationships within a group. To date, however, quantitative studies on intragroup affiliative behaviours in social carnivores have been limited. Here, we investigated the social functions of the two most commonly observed affiliative behaviours in captive African lions (Panthera leo: head rubbing and licking. We conducted behavioural observations on a captive group of lions composed of 7 males and 14 females, and tested hypotheses regarding three social functions: tension reduction, social bonding, and social status expression. Disproportionately frequent male-male and female-to-male head rubbing was observed, while more than 95% of all licking interactions occurred in female-female dyads. In accordance with the social bond hypothesis, and in disagreement with the social status expression hypothesis, both head rubbing and licking interactions were reciprocal. After controlling for spatial association, the dyadic frequency of head rubbing was negatively correlated with age difference while licking was positively correlated with relatedness. Group reunion after daily separation did not affect the frequencies of the affiliative behaviours, which was in disagreement with the predictions from the tension reduction hypothesis. These results support the social bond hypothesis for the functions of head rubbing and licking. Different patterns of affiliative behaviour between the sexes may reflect differences in the relationship quality in each sex or the differential predisposition to licking due to its original function in offspring care.

  7. Characterization of a Bioflocculant Produced by a Consortium of Halomonas sp. Okoh and Micrococcus sp. Leo

    Directory of Open Access Journals (Sweden)

    Anthony I. Okoh

    2013-10-01

    Full Text Available The physicochemical and flocculating properties of a bioflocculant produced by a bacterial consortium composed of Halomonas sp. Okoh and Micrococcus sp. Leo were investigated. The purified bioflocculant was cation and pH dependent, and optimally flocculated kaolin clay suspension at a dosage of 0.1 mg/mL. The flocculating activity of the bioflocculant was stimulated in the presence of Ca2+, Mn2+, Al3+ and had a wide pH range of 2–10, with the highest flocculating activity of 86% at pH 8. The bioflocculant was thermostable and retained more than 70% of its flocculating activity after being heated at 80 °C for 30 min. Thermogravimetric analyses revealed a partial thermal decomposition of the biofloculant at 400 °C. The infrared spectrum showed the presence of hydroxyl, carboxyl and amino moieties as functional groups. The bioflocculant produced by the bacterial consortium appears to hold promising alternative to inorganic and synthetic organic flocculants that are widely used in wastewater treatment.

  8. Routing Technology for LEO Satellite Network%LEO卫星网络的路由技术

    Institute of Scientific and Technical Information of China (English)

    孙利民; 卢泽新; 吴志美

    2004-01-01

    低地球轨道LEO(Low Earth Orbit)卫星系统因能够提供多媒体通信服务而成为卫星通信研究的热点.由于LEO卫星相对地面高速运行和其网络拓扑结构的快速动态变化,路由问题一直是LEO卫星网络重点解决的难题之一.该文介绍了LEO卫星网络中路由及其相关技术方面的一些工作,分析了LEO卫星网络的拓扑结构特点,然后着重对LEO卫星网络的路由机制进行分类和描述,特别说明LEO卫星网络的切换对路由的影响,最后提出设计LEO卫星网络路由机制应考虑的主要方面.

  9. Relative Navigation in LEO by Carrier-Phase Differential GPS with Intersatellite Ranging Augmentation

    Directory of Open Access Journals (Sweden)

    Alfredo Renga

    2013-01-01

    Full Text Available Carrier-phase differential GPS (CDGPS is a promising technology for accurate relative navigation in LEO formations of cooperating satellites, but navigation filter robustness against poor GPS geometry and noisy measurements has to be improved. This can be performed by augmenting the navigation filter with intersatellite local ranging measurements, as the ones provided by ranging transponders or GNSS-like systems. In this paper, an augmented CDGPS navigation filter is proposed for the formation of two satellites characterized by a short, varying baseline, relevant to next generation Synthetic Aperture Radar missions. Specifically, a cascade-combination of dynamic and kinematic filters which processes double-differenced code and carrier measurements on two frequencies, as well as local inter-satellite ranging measurements, is used to get centimeter-level baseline estimates. The augmented filter is validated by numerical simulations of the formation orbital path. Results demonstrate that the proposed approach is effective in preserving the centimeter-level accuracy achievable by a CDGPS-only filter also in the presence of a poor GDOP or a limited number of GPS satellites in view.

  10. Unlicensed Spectrum Sharing Game Between LEO Satellites and Terrestrial Cognitive Radio Networks

    Institute of Scientific and Technical Information of China (English)

    XIE Zhuochen; MA Lu; LIANG Xuwen

    2012-01-01

    By cognitive radio,the low Earth orbit (LEO) satellites may prefer to operate in the unlicensed spectrum which is open to all the users,and compete for the limited resources with terrestrial cognitive radio networks (CRNs).The competition can be regarded as a game and analyzed with game theory.This particular unlicensed spectrum sharing problem is modeled here,and the special properties of “spatially-distinguished-interference” and the short period of the interactions between satellites and terrestrial CRNs are explored.Then,the problem is formulated as a “partially-blind” finitely repeated prisoner's dilemma by game theory.Finally,we begin with two promising spectrum sharing schemes,which can be used to enforce the frequency reuse among the remotely located terrestrial CRN players as well as to overcome the observation noise.By analysis and comparison,it is proposed that the novel refreshing-contrite-tit-for-tat (R-CTFT) is the optimal spectrum sharing scheme.Simulation results verify that it can be used to utilize the spectrum most efficiently.

  11. Home range utilisation and territorial behaviour of lions (Panthera leo on Karongwe Game Reserve, South Africa.

    Directory of Open Access Journals (Sweden)

    Monika B Lehmann

    Full Text Available Interventionist conservation management of territorial large carnivores has increased in recent years, especially in South Africa. Understanding of spatial ecology is an important component of predator conservation and management. Spatial patterns are influenced by many, often interacting, factors making elucidation of key drivers difficult. We had the opportunity to study a simplified system, a single pride of lions (Panthera leo after reintroduction onto the 85 km(2 Karongwe Game Reserve, from 1999-2005, using radio-telemetry. In 2002 one male was removed from the paired coalition which had been present for the first three years. A second pride and male were in a fenced reserve adjacent of them to the east. This made it possible to separate social and resource factors in both a coalition and single male scenario, and the driving factors these seem to have on spatial ecology. Male ranging behaviour was not affected by coalition size, being driven more by resource rather than social factors. The females responded to the lions on the adjacent reserve by avoiding the area closest to them, therefore females may be more driven by social factors. Home range size and the resource response to water are important factors to consider when reintroducing lions to a small reserve, and it is hoped that these findings lead to other similar studies which will contribute to sound decisions regarding the management of lions on small reserves.

  12. Home range utilisation and territorial behaviour of lions (Panthera leo) on Karongwe Game Reserve, South Africa.

    Science.gov (United States)

    Lehmann, Monika B; Funston, Paul J; Owen, Cailey R; Slotow, Rob

    2008-01-01

    Interventionist conservation management of territorial large carnivores has increased in recent years, especially in South Africa. Understanding of spatial ecology is an important component of predator conservation and management. Spatial patterns are influenced by many, often interacting, factors making elucidation of key drivers difficult. We had the opportunity to study a simplified system, a single pride of lions (Panthera leo) after reintroduction onto the 85 km(2) Karongwe Game Reserve, from 1999-2005, using radio-telemetry. In 2002 one male was removed from the paired coalition which had been present for the first three years. A second pride and male were in a fenced reserve adjacent of them to the east. This made it possible to separate social and resource factors in both a coalition and single male scenario, and the driving factors these seem to have on spatial ecology. Male ranging behaviour was not affected by coalition size, being driven more by resource rather than social factors. The females responded to the lions on the adjacent reserve by avoiding the area closest to them, therefore females may be more driven by social factors. Home range size and the resource response to water are important factors to consider when reintroducing lions to a small reserve, and it is hoped that these findings lead to other similar studies which will contribute to sound decisions regarding the management of lions on small reserves.

  13. Proper Motion of the Leo II Dwarf Galaxy Based On Hubble Space Telescope Imaging

    CERN Document Server

    Piatek, Slawomir; Olszewski, Edward W

    2016-01-01

    This article reports a measurement of the proper motion of Leo II, a dwarf galaxy that is a likely satellite of the Milky Way, based on imaging with the Hubble Space Telescope and Wide Field Camera 3. The measurement uses compact background galaxies as standards of rest in both channels of the camera for two distinct pointings of the telescope and a QSO in one channel for each pointing, resulting in the weighted average of six measurements. The measured proper motion in the the equatorial coordinate system is (mu_alpha, mu_delta) = (-6.9 +- 3.7, -8.7 +- 3.9) mas/century and in the Galactic coordinate system is (mu_l, mu_b) = (6.2 +- 3.9, -9.2 +- 3.7) mas/century. The implied space velocity with respect to the Galactic center is (Pi, Theta, Z) = (-37 +- 38, 117 +- 43, 40 +- 16) km/s or, expressed in Galactocentric radial and tangential components, (V_r, V_tan) = (21.9 +- 1.5, 127 +- 42) km/s. The space velocity implies that the instantaneous orbital inclination is 68 degrees, with a 95% confidence interval of ...

  14. In-Orbit Lifetime Prediction for LEO and HEO Based on Orbit Determination from TLE Data

    Science.gov (United States)

    Agueda, A.; Aivar, L.; Tirado, J.; Dolado, J. C.

    2013-08-01

    Objects in Low-Earth Orbits (LEO) and Highly Elliptical Orbits (HEO) are subjected to decay and re-entry into the atmosphere due mainly to the drag force. While being this process the best solution to avoid the proliferation of debris in space and ensure the sustainability of future space activities, it implies a threat to the population on ground. Thus, the prediction of the in-orbit lifetime of an object and the evaluation of the risk on population and ground assets constitutes a crucial task. This paper will concentrate on the first of these tasks. Unfortunately the lifetime of an object in space is remarkably difficult to predict. This is mainly due to the dependence of the atmospheric drag on a number of uncertain elements such as the density profile and its dependence on the solar activity, the atmospheric conditions, the mass and surface area of the object (very difficult to evaluate), its uncontrolled attitude, etc. In this paper we will present a method for the prediction of this lifetime based on publicly available Two-Line Elements (TLEs) from the American USSTRATCOM's Joint Space Operations Center (JSpOC). TLEs constitute an excellent source to access routinely orbital information for thousands of objects even though of their reduced and unpredictable accuracy. Additionally, the implementation of the method on a CNES's Java-based tool will be presented. This tool (OPERA) is executed routinely at CNES to predict the orbital lifetime of a whole catalogue of objects.

  15. The structural properties and star formation history of Leo T from deep LBT photometry

    CERN Document Server

    De Jong, J T A; Coleman, M G; Martin, N F; Bell, E F; Rix, H-W; Hill, J M; Skillman, E D; Sand, D J; Olszewski, E W; Zaritsky, D; Thompson, D; Giallongo, E; Ragazzoni, R; DiPaola, A; Farinato, J; Testa, V; Bechtold, J

    2008-01-01

    We present deep, wide-field g and r photometry of the transition type dwarf galaxy Leo T, obtained with the blue arm of the Large Binocular Telescope. The data confirm the presence of both very young (5 Gyr) stars. We study the structural properties of the old and young stellar populations by preferentially selecting either population based on their color and magnitude. The young population is significantly more concentrated than the old population, with half-light radii of 148+-16 and 104+-8 pc respectively, and their centers are slightly offset. Approximately 10% of the total stellar mass is estimated to be represented by the young stellar population. Comparison of the color-magnitude diagram (CMD) with theoretical isochrones as well as numerical CMD-fitting suggest that star formation began over 10 Gyr ago and continued in recent times until at least a few hundred Myr ago. The CMD-fitting results are indicative of two distinct star formation bursts, with a quiescent period around 3 Gyr ago, albeit at low s...

  16. ALFALFA and WSRT Imaging of Extended H I Features in the Leo Cloud of Galaxies

    Science.gov (United States)

    Leisman, Lukas; Haynes, Martha P.; Giovanelli, Riccardo; Józsa, Gyula; Adams, Elizabeth A. K.; Hess, Kelley M.

    2016-12-01

    We present Arecibo Legacy Fast ALFA (ALFALFA) H I observations of a well-studied region of the Leo Cloud, which includes the NGC 3227 group and the NGC 3190 group. We detect optically dark H I tails and plumes with extents potentially exceeding 600 kpc, well beyond the field of view of previous observations. These H I features contain ˜40 per cent of the total H I mass in the NGC 3227 group and ˜10 per cent of the NGC 3190 group. We also present Westerbork Synthesis Radio Telescope (WSRT) maps which show the complex morphology of the extended emission in the NGC 3227 group. We comment on previously proposed models of the interactions in these groups and the implications for the scale of group processing through interactions. Motivated by the extent of the H I plumes, we place the H I observations in the context of the larger loose group, demonstrating the need for future sensitive, wide field H I surveys to understand the role of group processing in galaxy evolution.

  17. The Leo I Cloud Secular nuclear evolution of NGC 3379, NGC 3384, and NGC 3368?

    CERN Document Server

    Silchenko, O K; Afanasiev, V L; Chavushyan, V H; Valdés, J R

    2003-01-01

    The central regions of the three brightest members of the Leo I galaxy group -- NGC 3368, NGC 3379, and NGC 3384 -- are investigated by means of 2D spectroscopy. In all three galaxies we have found separate circumnuclear stellar and gaseous subsystems -- more probably, disks -- whose spatial orientations and spins are connected to the spatial orientation of the supergiant intergalactic HI ring reported previously by Schneider et al. (1983) and Schneider (1985, 1989). In NGC 3368 the global gaseous disk seems also to be inclined to the symmetry plane of the stellar body, being probably of external origin. Although the rather young mean stellar age and spatial orientations of the circumnuclear disks in NGC 3379, NGC 3384, and NGC 3368 could imply their recent formation from material of the intergalactic HI cloud, the time scale of these secondary formation events, of order 3 Gyr, does not support the collision scenario of Rood & Williams (1985), but is rather in line with the ideas of Schneider (1985, 1989)...

  18. Fiber type and metabolic characteristics of lion (Panthera leo), caracal (Caracal caracal) and human skeletal muscle.

    Science.gov (United States)

    Kohn, Tertius Abraham; Burroughs, Richard; Hartman, Marthinus Jacobus; Noakes, Timothy David

    2011-06-01

    Lion (Panthera leo) and caracal (Caracal caracal) skeletal muscle samples from Vastus lateralis, Longissimus dorsi and Gluteus medius were analyzed for fiber type and citrate synthase (CS; EC 2.3.3.1), 3-hydroxyacyl Co A dehydrogenase (3HAD; EC 1.1.1.35), phosphofructokinase-1 (PFK; EC 2.7.1.11), creatine kinase (CK; EC 2.7.3.2), phosphorylase (PHOS; EC 2.4.1.1) and lactate dehydrogenase (LDH; EC 1.1.1.27) activities and compared to human runners, the latter also serving as validation of methodology. Both felids had predominantly type IIx fibers (range 50-80%), whereas human muscle had more types I and IIa. Oxidative capacity of both felids (CS: 5-9 μmol/min/g ww and 3HAD: 1.4-2.6 μmol/min/g ww) was lower than humans, whereas the glycolytic capacity was elevated. LDH activity of caracal (346 ± 81) was higher than lion (227 ± 62 μmol/min/g ww), with human being the lowest (55 ± 17). CK and PHOS activities were also higher in caracal and lion compared to human, but PFK was lower in both felid species. The current data and past research are illustrated graphically showing a strong relationship between type II fibers and sprinting ability in various species. These data on caracal and lion muscles confirm their sprinting behavior.

  19. Radiated EMC& EMI Management During Design Qualification and Test Phases on LEO Satellites Constellation

    Science.gov (United States)

    Blondeaux, H.; Terral, M.; Gutierrez-Galvan, R.; Baud, C.

    2016-05-01

    The aim of the proposed paper is to present the global radiated EMC/EMI approach applied by Thales Alenia Space in the frame of a telecommunication Low Earth Orbit (LEO) satellites constellation program. The paper will present this approach in term of analyses, of specific characterisation and of sub-system and satellite tests since first design reviews up-to satellite qualification tests on Prototype Flight Model (PFM) and to production tests on reduced FMs. The global aim is : 1 - to reduce risk and cost (units EMC delta qualification, EMC tests at satellite level for the 81 Space Vehicles (SV) through appropriated EMC analyses (in term of methodologies and contours) provided in the frame of design reviews.2 - to early anticipate potential critical case to reduce the impact in term of engineering/qualification/test extra cost and of schedule.3 - to secure/assure the payload and SV design/layout.4 - to define and optimize the EMC/EMI test campaigns to be performed on Prototype Flight Model (PFM) for complete qualification and on some FMs for industrial qualification/validation.The last part of the paper is dedicated to system Bite Error Rate (BER) functional test performed on PFM SV to demonstrate the final compatibility between the three on-board payloads and to the Internal EMC tests performed on PFM and some FMs to demonstrate the SV panel RF shielding efficiency before and after environmental tests and the Thales Alenia Space (TAS) and Orbital AKT (OATK) workmanships reproducibility.

  20. Bioensayo de toxicidad aguda con plantas nativas para evaluar un derrame de petróleo

    Directory of Open Access Journals (Sweden)

    Vivien Pentreath

    2015-06-01

    Full Text Available Los bioensayos con plantas constituyen una excelente herramienta en la evaluación del riesgo ambiental y, en particular, la utilización de semillas de plantas vasculares es recomendada debido a su mayor sensibilidad. El objetivo del presente trabajo fue evaluar el comportamiento de plantas nativas para ser utilizadas como indicador biológico de contaminación ambiental con petróleo en relación con un bioindicador estandarizado. Se analizó el Índice de Germinación (IG de Lactuca sativa L., Atriplex lampa (Moq. D.Dietri. y Prosopis denudans Benth. en treinta muestras de suelo extraídas de un yacimiento petrolero a fin de detectar efectos fitotóxicos. El IG es un método económico, rápido y reproducible para determinar toxicidad de suelo, ayudando a caracterizar áreas con suelos contaminados. La germinación de Atriplex lampa (Moq. D.Dietri. y Prosopis denudans resultó más resistente en los suelos contaminados de un yacimiento petrolero que el bioindicador de referencia utilizado (Lactuca sativa L..

  1. Analysis and modeling of high temporal resolution spectroscopic observations of flares on AD Leo

    CERN Document Server

    Crespo-Chacon, I; Foing, B H; García-Álvarez, D; López-Santiago, J; Montes, D

    2006-01-01

    We report the results of a high temporal resolution spectroscopic monitoring of the flare star AD Leo. During 4 nights, more than 600 spectra were taken in the optical range using the Isaac Newton Telescope (INT) and the Intermediate Dispersion Spectrograph (IDS). We have observed a large number of short and weak flares occurring very frequently (flare activity > 0.71 hours-1). This is in favour of the very important role that flares can play in stellar coronal heating. The detected flares are non white-light flares and, though most of solar flares belong to this kind, very few such events had been previously observed on stars. The behaviour of different chromospheric lines (Balmer series from H_alpha to H_11, Ca II H & K, Na I D_1 & D_2, He I 4026 AA and He I D_3) has been studied in detail for a total of 14 flares. We have also estimated the physical parameters of the flaring plasma by using a procedure which assumes a simplified slab model of flares. All the obtained physical parameters are consist...

  2. Selected clinical, biochemical, and electrolyte alterations in anesthetized captive tigers (Panthera tigris) and lions (Panthera leo).

    Science.gov (United States)

    Reilly, Sabrina; Seddighi, M Reza; Steeil, James C; Sura, Patricia; Whittemore, Jacqueline C; Gompf, Rebecca E; Elliott, Sarah B; Ramsay, Edward C

    2014-06-01

    A prospective study to assess changes in selected plasma biochemistry and electrolyte values, plasma insulin and aldosterone concentrations, and electrocardiography (ECG) was performed on eight female captive tigers (Panthera tigris) and three lions (Panthera leo) undergoing general anesthesia for elective laparoscopic ovariectomy. Each animal was sedated with medetomidine (18-25 microg/kg) and midazolam (0.06-0.1 mg/kg) intramuscularly, and anesthesia was induced with ketamine (1.9-3.5 mg/kg) intramuscularly and maintained with isoflurane. Venous blood samples were collected and analyzed for plasma biochemistry parameters and insulin and aldosterone concentrations. An ECG was recorded at the time of each blood sample collection. Mean plasma potassium, glucose, phosphorus, and aldosterone concentrations increased during anesthesia (P < or = 0.05). One tiger developed hyperkalemia (6.5 mmol/L) 2.5 hr after anesthetic induction. Plasma insulin concentrations were initially below the low end of the domestic cat reference interval (72-583 pmol/L), but mean insulin concentration increased (P < or = 0.05) over time compared with the baseline values. Three tigers and two lions had ECG changes that were representative of myocardial hypoxemia. Based on these results, continuous monitoring of clinical and biochemical alterations during general anesthesia in large nondomestic felids is warranted, and consideration should be given to reversal of medetomidine in these animals should significant changes in electrolytes or ECG occur.

  3. Evaluation of microsatellite markers for populations studies and forensic identification of African lions (Panthera leo).

    Science.gov (United States)

    Miller, Susan M; Harper, Cindy K; Bloomer, Paulette; Hofmeyr, Jennifer; Funston, Paul J

    2014-01-01

    The South African lion (Panthera leo) population is highly fragmented. One-third of its wild lions occur in small (<1000 km(2)) reserves. These lions were reintroduced from other areas of the species' historical range. Management practices on these reserves have not prioritized genetic provenance or heterozygosity. These trends potentially constrain the conservation value of these lions. To ensure the best management and long-term survival of these subpopulations as a viable collective population, the provenance and current genetic diversity must be described. Concurrently, poaching of lions to supply a growing market for lion bones in Asia may become a serious conservation challenge in the future. Having a standardized, validated method for matching confiscated lion parts with carcasses will be a key tool in investigating these crimes. We evaluated 28 microsatellites in the African lion using samples from 18 small reserves and 1 captive facility in South Africa, two conservancies in Zimbabwe, and Kruger National and Kgalagadi Transfrontier Parks to determine the loci most suited for population management and forensic genetic applications. Twelve microsatellite loci with a match probability of 1.1×10(-5) between siblings were identified for forensics. A further 10 could be added for population genetics studies.

  4. Genetic Evidence for Contrasting Wetland and Savannah Habitat Specializations in Different Populations of Lions (Panthera leo).

    Science.gov (United States)

    Moore, Andy E; Cotterill, Fenton P D Woody; Winterbach, Christiaan W; Winterbach, Hanlie E K; Antunes, Agostinho; O'Brien, Stephen J

    2016-03-01

    South-central Africa is characterized by an archipelago of wetlands, which has evolved in time and space since at least the Miocene, providing refugia for animal species during Pleistocene arid episodes. Their importance for biodiversity in the region is reflected in the evolution of a variety of specialist mammal and bird species, adapted to exploit these wetland habitats. Populations of lions (Panthera leo) across south-central and east Africa have contrasting signatures of mitochondrial DNA haplotypes and biparental nuclear DNA in wetland and savannah habitats, respectively, pointing to the evolution of distinct habitat preferences. This explains the absence of genetic admixture of populations from the Kalahari savannah of southwest Botswana and the Okavango wetland of northern Botswana, despite separation by only 500 km. We postulate that ancestral lions were wetland specialists and that the savannah lions evolved from populations that were isolated during arid Pleistocene episodes. Expansion of grasslands and the resultant increase in herbivore populations during mesic Pleistocene climatic episodes provided the stimulus for the rapid population expansion and diversification of the highly successful savannah lion specialists. Our model has important implications for lion conservation.

  5. Lion (Panthera leo) populations are declining rapidly across Africa, except in intensively managed areas.

    Science.gov (United States)

    Bauer, Hans; Chapron, Guillaume; Nowell, Kristin; Henschel, Philipp; Funston, Paul; Hunter, Luke T B; Macdonald, David W; Packer, Craig

    2015-12-01

    We compiled all credible repeated lion surveys and present time series data for 47 lion (Panthera leo) populations. We used a Bayesian state space model to estimate growth rate-λ for each population and summed these into three regional sets to provide conservation-relevant estimates of trends since 1990. We found a striking geographical pattern: African lion populations are declining everywhere, except in four southern countries (Botswana, Namibia, South Africa, and Zimbabwe). Population models indicate a 67% chance that lions in West and Central Africa decline by one-half, while estimating a 37% chance that lions in East Africa also decline by one-half over two decades. We recommend separate regional assessments of the lion in the World Conservation Union (IUCN) Red List of Threatened Species: already recognized as critically endangered in West Africa, our analysis supports listing as regionally endangered in Central and East Africa and least concern in southern Africa. Almost all lion populations that historically exceeded ∼ 500 individuals are declining, but lion conservation is successful in southern Africa, in part because of the proliferation of reintroduced lions in small, fenced, intensively managed, and funded reserves. If management budgets for wild lands cannot keep pace with mounting levels of threat, the species may rely increasingly on these southern African areas and may no longer be a flagship species of the once vast natural ecosystems across the rest of the continent.

  6. Ultrasonographic and laparoscopic evaluation of the reproductive tract of the captive female African lion (Panthera leo).

    Science.gov (United States)

    Kirberger, Robert M; Schulman, Martin L; Hartman, Marthinus J

    2011-09-15

    The use of transabdominal ultrasonography to assess the oestrous cycle has not been previously described in the African lion (Panthera leo). Twelve sexually mature lionesses and five female cubs had their reproductive organs assessed by transabdominal ultrasound. Ovarian findings were compared to laparoscopic findings while performing laparoscopic ovariectomy or salpingectomy. Vaginal cytology was performed and serum progesterone levels were determined. By combining all data the oestrous cycle stage of each lion was determined. One lion was far pregnant and was not operated on. In adults a uterine body could be seen ultrasonographically in 67% of lions while mural structures could be distinguished in 44% of lions. Five uterine horns could be seen in 3 lions. In 12 adults 10 ovaries were found of which eight had discernable follicles or luteal structures. During laparoscopy 12 active ovaries were seen with luteal structures seen in 11 ovaries and follicles in 2 ovaries. Using laparoscopy as the gold standard, ultrasonography had a sensitivity of 66% and specificity of 83% to detect ovarian reproductive activity. Two uterine cysts and a cluster of periovarian cysts were seen in three different lions. Three lions were pregnant, two were in oestrus, three in a luteal phase (dioestrus), and four were in anoestrus. Transabdominal ultrasound in combination with serum progesterone levels and vaginal cytology can be used to assess ovarian cyclical activity with reasonable accuracy in captive bred lions. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO

    Science.gov (United States)

    Cucinotta, F. A.; Wilson, J. W.; Williams, J. R.; Dicello, J. F.

    2000-01-01

    We compare models of radiation transport and biological response to physical and biological dosimetry results from astronauts on the Mir space station. Transport models are shown to be in good agreement with physical measurements and indicate that the ratio of equivalent dose from the Galactic Cosmic Rays (GCR) to protons is about 3/2:1 and that this ratio will increase for exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cells; a track-structure model and the linear-quadratic model with linear energy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement with data for aberrations in lymphocytes of Mir crew members: however there are differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major difference in the models is the increased effectiveness predicted by the track model for low charge and energy ions with LET near 10 keV/micrometers. The results of our calculations indicate that aluminum shielding, although providing important mitigation of the effects of trapped radiation, provides no protective effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measure until about 100 g/cm 2 of material is used.

  8. ALMA data suggest the presence of a spiral structure in the inner wind of CW Leo

    CERN Document Server

    Decin, L; Neufeld, D; Steffen, W; Melnick, G; Lombaert, R

    2014-01-01

    (abbreviated) We aim to study the inner wind of the well-known AGB star CW Leo. Different diagnostics probing different geometrical scales have pointed toward a non-homogeneous mass-loss process: dust clumps are observed at milli-arcsec scale, a bipolar structure is seen at arcsecond-scale and multi-concentric shells are detected beyond 1". We present the first ALMA Cycle 0 band 9 data around 650 GHz. The full-resolution data have a spatial resolution of 0".42x0".24, allowing us to study the morpho-kinematical structure within ~6". Results: We have detected 25 molecular lines. The emission of all but one line is spatially resolved. The dust and molecular lines are centered around the continuum peak position. The dust emission has an asymmetric distribution with a central peak flux density of ~2 Jy. The molecular emission lines trace different regions in the wind acceleration region and suggest that the wind velocity increases rapidly from about 5 R* almost reaching the terminal velocity at ~11 R*. The channel...

  9. Sling-on-a-Ring: Structure for an elevator to LEO

    CERN Document Server

    Meulenberg, Andrew

    2015-01-01

    Various proposed space elevators may bypass the financial and environmental limits on rocket technology, but all have their own problems. A Low-Earth-Orbit, LEO, rotovator-based space-elevator version called 'sling-on-a-ring' may overcome them. This mass-lifting system uses the spatial stability of an orbital ring, accessorized for transfer and storage of momentum and electrical power. A high-tensile-strength equatorial circum-terra loop of colossal-carbon tube, CCT, fiber has solar-power and station-keeping units and rotating sling modules. Long sling assemblies, ~600 km, periodically descend into the atmosphere to ~13 km. At perigee, the sling rotational tip velocity almost cancels the orbital-ring velocity relative to Earth surface. Split-second timing detaches a ~10 ton payload from an ordinary aircraft and jerks it into space by sling momentum, with the proven specific strength of CCTs now under development. This system eliminates the immense mass in space of other space-elevator systems, but needs extre...

  10. COMPRAS DE ITENS-NÃO-CRÍTICOS NUMA EMPRESA DE PETRÓLEO

    Directory of Open Access Journals (Sweden)

    Alice Maria Silva Teixeira de Souza

    2008-12-01

    Full Text Available A área de compras, recentemente, recebeu um grande avanço em termos de pesquisa, dentro do mundo acadêmico, pois o número de publicações referente ao tema aumentou significativamente. No contexto empresarial, "compras" deixou de ter apenas uma motivação operacional, assumindo agora uma importância estratégica. Como conseqüência, muitas empresas vêm desenvolvendo a sua área de compras. O objetivo desse artigo é o de analisar o processo atual de compras de uma empresa da indústria de Petróleo para itens não estratégicos. Nesse sentido, foram aplicados 18 questionários em entrevistas estruturadas com funcionários envolvidos com o processo de compras da empresa, número que englobou 50% do total de funcionários do processo de compras. Como resultado, verificou-se uma aderência entre o planejamento desse processo na empresa com a literatura acadêmica. Porém, a execução e a operação do que foi planejado necessita de melhorias, pois está, em alguns aspectos, atuando sob antigos paradigmas. Nesse sentido, o presente artigo contribui com propostas de melhorias.

  11. Absolute properties of the main-sequence eclipsing binary FM Leo

    CERN Document Server

    Ratajczak, M; Schwarzenberg-Czerny, A; Dimitrov, W; Konacki, M; Helminiak, K G; Bartczak, P; Fagas, M; Kaminski, K; Kankiewicz, P; Borczyk, W; Rozek, A

    2009-01-01

    First spectroscopic and new photometric observations of the eclipsing binary FM Leo are presented. The main aims were to determine orbital and stellar parameters of two components and their evolutionary stage. First spectroscopic observations of the system were obtained with DDO and PST spectrographs. The results of the orbital solution from radial velocity curves are combined with those derived from the light-curve analysis (ASAS-3 photometry and supplementary observations of eclipses with 1 m and 0.35 m telescopes) to derive orbital and stellar parameters. JKTEBOP, Wilson-Devinney binary modelling codes and a two-dimensional cross-correlation (TODCOR) method were applied for the analysis. We find the masses to be M_1 = 1.318 $\\pm$ 0.007 and M_2 = 1.287 $\\pm$ 0.007 M_sun, the radii to be R_1 = 1.648 $\\pm$ 0.043 and R_2 = 1.511 $\\pm$ 0.049 R_sun for primary and secondary stars, respectively. The evolutionary stage of the system is briefly discussed by comparing physical parameters with current stellar evoluti...

  12. PREACHER AS A CHARACTER IN THE CREATIVE WORK OF LEO TOLSTOY AND GEORGE ELIOT

    Directory of Open Access Journals (Sweden)

    Irina Fedorovna Gnyusova

    2014-11-01

    Full Text Available The article analyzes characters of clergymen and the process of creating a specifi c type of a preacher in Leo Tolstoy’s works. The researcher tries to prove that this process was strongly infl uenced by Tolstoy’s close attention to the preacher characters in George Eliot’s works. This can be proved by Tolstoy’s letters, diary and notes in the books from the writer’s personal library. The main features of Tolstoy’s preacher character are demonstrated by the example of Prince Nekhlyudov (Resurrection. Proclaiming evangelical truth, he is not a member of any confession; he does not promulgate his views, but he proves his case by his actions and his way of life. He rejects earthly comfort and goods and voluntarily becomes integrated into people’s life. Having walked his way of repentance of former sins, he cultivates the ability to forgive and have mercy. George Eliot also accents these features in the key characters of her books, analyzed in this article (Janet’s repentance, Adam Bede and Felix Holt, the Radical. Eliot’s version of preaching becomes a certain guide for Tolstoy in the process of shaping a new type of character in his late works.

  13. Development of access-based metrics for site location of ground segment in LEO missions

    Directory of Open Access Journals (Sweden)

    Hossein Bonyan Khamseh

    2010-09-01

    Full Text Available The classical metrics of ground segment site location do not take account of the pattern of ground segment access to the satellite. In this paper, based on the pattern of access between the ground segment and the satellite, two metrics for site location of ground segments in Low Earth Orbits (LEO missions were developed. The two developed access-based metrics are total accessibility duration and longest accessibility gap in a given period of time. It is shown that repeatability cycle is the minimum necessary time interval to study the steady behavior of the two proposed metrics. System and subsystem characteristics of the satellite represented by each of the metrics are discussed. Incorporation of the two proposed metrics, along with the classical ones, in the ground segment site location process results in financial saving in satellite development phase and reduces the minimum required level of in-orbit autonomy of the satellite. To show the effectiveness of the proposed metrics, simulation results are included for illustration.

  14. Model-Based GN and C Simulation and Flight Software Development for Orion Missions beyond LEO

    Science.gov (United States)

    Odegard, Ryan; Milenkovic, Zoran; Henry, Joel; Buttacoli, Michael

    2014-01-01

    For Orion missions beyond low Earth orbit (LEO), the Guidance, Navigation, and Control (GN&C) system is being developed using a model-based approach for simulation and flight software. Lessons learned from the development of GN&C algorithms and flight software for the Orion Exploration Flight Test One (EFT-1) vehicle have been applied to the development of further capabilities for Orion GN&C beyond EFT-1. Continuing the use of a Model-Based Development (MBD) approach with the Matlab®/Simulink® tool suite, the process for GN&C development and analysis has been largely improved. Furthermore, a model-based simulation environment in Simulink, rather than an external C-based simulation, greatly eases the process for development of flight algorithms. The benefits seen by employing lessons learned from EFT-1 are described, as well as the approach for implementing additional MBD techniques. Also detailed are the key enablers for improvements to the MBD process, including enhanced configuration management techniques for model-based software systems, automated code and artifact generation, and automated testing and integration.

  15. Íleo biliar, causa poco frecuente de obstrucción intestinal

    Directory of Open Access Journals (Sweden)

    A. García-Marín

    2014-07-01

    Full Text Available El íleo biliar, rara complicación de la colelitiasis, se caracteriza por la oclusión intestinal secundaria a la impactación de un lito biliar en algún punto del tracto digestivo debido a la existencia de una fístula bilioentérica. El objetivo del trabajo es analizar nuestra experiencia mediante un estudio retrospectivo durante un período de 12 años. Se incluyeron 14 casos (10 mujeres y 4 varones con una mediana de edad de 81 años y comorbilidades en 11. La principal alteración analítica fue elevación de urea (mediana 79 mg/dl. El diagnóstico se confirmó mediante tomografía en 10 casos y radiografía simple de abdomen en 4. El cálculo se localizó en yeyuno en 6 casos, íleon en 6 y sigmoides en uno con un tamaño medio de 3 cm. La fístula fue colecistoduodenal en 11 casos, colecistocólica en uno e idiopática en uno. Fallecieron 2 pacientes, incluido el caso no operado.

  16. Microencapsulação de óleo essencial de laranja Microencapsulation of orange essential oil

    Directory of Open Access Journals (Sweden)

    Lucy C. ABURTO

    1998-04-01

    Full Text Available Microcápsulas contendo óleo de laranja foram obtidas utilizando secagem por atomização. Para a análise da influência dos componentes na retenção total de óleo, prepararam-se três formulações com concentrações diferentes de goma arábica e amido modificado, mantendo constante a concentração de maltodextrina (36% e óleo (10%. As três fórmulas receberam três tratamentos térmicos (180°C, 200°C e 220°C, resultando na obtenção de nove produtos. As retenções de óleo superficial e interno das microcápsulas foram quantificadas e um estudo microscópico da estrutura das microcápsulas foi realizado. Os resultados demonstraram que a microestrutura das cápsulas eram similares e que as três temperaturas empregadas não alteraram a microencapsulação. A microscopia ótica revelou microcápsulas globosas, com diâmetros variáveis e superfícies irregulares. Ao microscópio eletrônico de varredura verificou-se que as faces das microcápsulas eram predominantemente rugosas, exibiam perfurações e quando quebradas demonstravam paredes porosas. A forma e os diâmetros das microcápsulas não dependeram do amido modificado, mas sua presença conferiu melhor retenção de óleo. A maior retenção de óleo, 94%, foi obtida com a fórmula contendo 10% de amido modificado, 36% de maltodextrina e 10% de óleo essencial de laranja, independente da temperatura de secagem.It was done microencapsulation of natural essencial orange oil through spray-drying. The purpose was to use the best proportion of wall materials among maltodextrin, acacia gum, and modified starch (capsul in order to retain greater amount of orange oil. The orange oil (10% and maltodextrin (36% remained constant. Three spray drying temperatures were employed: 180°C, 200°C and 220°C, therefore, nine final products were obtained. The superficial and inner oil concentrations were measured. The microcapsules were also examined through optical and scanning electron

  17. Caracterización de propóleos provenientes del municipio de Caldas obtenido por dos métodos de recolección

    Directory of Open Access Journals (Sweden)

    Julián Martínez G.

    2012-04-01

    Full Text Available Objetivo. Determinar las características fisicoquímicas y la actividad antimicrobiana de propóleos de Apis mellifera, provenientes del municipio de Caldas, obtenidos por dos métodos de recolección. Materiales y métodos. Se utilizaron dos métodos de recolección: de raspado y trampa plastica. Se estableció el contenido de cera, ceniza, material insoluble y resina de los propóleos crudos. Al extracto etanólico de los propóleos se les determinó el perfil cromatográfico (GC-MS y el espectro UV; además, se evaluó la actividad antimicrobiana in vitro frente a hongos (Aspergillus sp., Penicillium sp., Colletotrichum acutatum y C. gloesporioides, y bacterias (Salmonella tiphy, Bacillus subtilis, Staphylococcus aureus y Escherichia coli. Resultados. El material obtenido mediante malla matrizada presentó un perfil químico amplio, buena actividad antimicrobiana y mejores parámetros de calidad, de acuerdo con estándares establecidos por normas internacionales que los propóleos obtenidos por el método de raspado. Además, pudo observarse que la acción antimicrobiana de los propóleos fue dependiente de la concentración del extracto y del hongo o bacteria evaluada. Conclusiones. La composición química y la actividad antibacteriana y antifúngica de los propóleos están relacionadas con el método de recolección. El presente estudio aporta información para la selección de la técnica de cosecha del propóleo de acuerdo con la aplicación que se desee dar.

  18. Óleos essenciais de folhas de diversas espécies: propriedades antioxidantes e antibacterianas no crescimento espécies patogênicas

    Directory of Open Access Journals (Sweden)

    Cíntia Alvarenga Santos Fraga Miranda

    Full Text Available RESUMO Os óleos essenciais apresentam possibilidade de serem empregados nas indústrias de alimentos, bebidas, produtos de higiene pessoal e cosméticos para evitar ou reduzir a deterioração lipídica e a contaminação por micro-organismos. Este trabalho teve como objetivos avaliar as propriedades funcionais antimicrobianas e antioxidantes de óleos essenciais de folhas frescas de Coniza bonariensis, Parthenium hysterophorus, Tithonia diversifolia, Ambrosia polystachya, Hedychium coronarium e Baccharis dracunculifolia, extraídos por hidrodestilação. O potencial antioxidante foi avaliado pelas metodologias do consumo do radical DPPH e da inibição da oxidação do sistema β-caroteno/ácido linoleico. A sensibilidade das bactérias Salmonella Cholerasuis, Listeria monocytogenes, Staphylococcus aureus e Escherichia coli frente aos óleos essenciais foi determinada pela utilização do método de difusão em cavidade ágar. Os óleos essenciais destacaram-se pelo elevado conteúdo de terpenoides. Todos os óleos essenciais avaliados pela metodologia do sequestro do radical DPPH não apresentaram CI50 significativos. Pela metodologia do β-caroteno/ácido linoleico, os óleos essenciais de T. diversifolia e H. coronarium não apresentaram atividades significativas e os de C. bonariensis, P. hysterophorus, A. polystachya, e B. dracunculifolia apresentaram CI50 superiores a maior concentração avaliada. Os óleos essenciais das espécies C. bonariensis, T. diversifolia, H. coronarium e de B. dracunculifolia apresentaram atividade antibacteriana para bactérias Gramnegativas e Gram-positivas, com exceção do óleo volátil de P. hysterophorus, que não impediu o crescimento de nenhuma das cepas bacterianas testadas. O óleo essencial de A. polystachya apresentou potencial antibacteriano apenas nas cepas de S. aureus.

  19. Bioatividade de óleos essenciais no controle de Botrytis cinerea isolado de morangueiro Essential oils bioactivity in strawberry grey mould control

    Directory of Open Access Journals (Sweden)

    E.R. Lorenzetti

    2011-01-01

    Full Text Available Objetivou-se avaliar o uso de óleos essenciais sobre isolados de Botrytis cinerea, causador do mofo cinzento em morangueiro. Foram testados óleos essenciais de capim-limão, palmarosa, citronela, cravo, canela, menta, lavanda, tangerina, eucalipto, melaleuca, alecrim e laranja, todos estes analisados em cromatógrafo a gás acoplado a detector de massas, para identificação dos principais componentes dos óleos. Foram avaliados o crescimento micelial, produção e germinação de conídios de B. cinerea, com a incorporação do óleo no meio de cultura. Realizou-se ainda uma avaliação de voláteis e a eficiência de óleos em isolado resistente a fungicida. Para cada teste, diferentes óleos apresentaram eficiência, contudo capim limão, palmarosa, canela e menta demonstraram os melhores efeitos em todos os testes realizados. Todos os tratamentos a base de óleos demonstraram efeito semelhante a um fungicida recomendado para a cultura, a base de tiofanato metílico. Dois tratamentos mostraram-se efetivos no caso de isolado resistente (óleo de capim limão e de canela. Óleos essenciais mostram-se como opção promissora para o desenvolvimento de possíveis produtos fitossanitários para o manejo de doenças em plantas.This study aimed evaluates essential oils in Botrytis cinerea isolates growth, which causes gray mould on strawberry. Were tested essential oils of lemon grass, palmrose, citronella, clove, cinnamon, mint, lavender, tangerine, eucalyptus, tea tree, rosemary and orange. The oils were analyzed in gas chromatograph attached to mass detector for identifying the mainly oils components. Were evaluated mycelial growth, conidia production and conidia germination of B. cinerea, with oil incorporation in culture medium. Were conducted an evaluation of oils volatile components and the efficiency of oils in fungicide-resistant isolate. For each test, different oils showed efficiency, however lemongrass, palmarosa, cinnamon and mint

  20. CARACTERIZAÇÃO QUÍMICA E EFEITO DO ÓLEO ESSENCIAL DE ERVA-DE-SANTA-MARIA SOBRE O ÁCARO-RAJADO DE MORANGUEIRO

    Directory of Open Access Journals (Sweden)

    JOÃO PAULO PEREIRA PAES

    2015-06-01

    Full Text Available O ácaro-rajado, Tetranychus urticae Koch (1836 (Acari: Tetranychidae, é a principal praga na cultura do morangueiro. O objetivo deste trabalho foi a caracterização química do óleo essencial de Chenopodium ambrosioides L. e a avaliação de seus efeitos sobre o ácaro-rajado. Os compostos do óleo essencial foram identificados pelasanálises de CG-DIC e CG-EM. A mortalidade e a oviposição foram avaliadas após a pulverização do óleo (2,5; 5,0; 7,5 e 10,0% v v-1 sobre fêmeas do ácaro-rajado. O rendimento do óleo essencial foi de 0,3%, e os compostos identificados foram (Z-ascaridol (87%, (E-ascaridol (5,04%, p-cimeno (4,83%, a- terpineno (1,24% e piperitona (0,7%. Os maiores valores para mortalidade e redução de oviposição observados foram 85% e 69%, respectivamente. O óleo essencial de C. ambrosioidesé uma opção promissora para o manejo do ácaro-rajado.

  1. Estudos dos constituintes químicos e atividade antibacteriana do óleo essencial de Lippia gracilis a Xanthomonas campestris pv. viticola "in vitro"

    Directory of Open Access Journals (Sweden)

    Morgana Mateus Santos

    2014-09-01

    Full Text Available Este trabalho foi realizado com o objetivo de estudar a eficácia de óleos essenciais de Lippia gracilis, no crescimento in vitro de Xcv. Foram utilizados oito óleos extraídos de L. gracilis, obtidos de diferentes manejos de cultivo, em três dosagens diferentes (200; 250 e 300 µL.L-1, testemunha com o oxicloreto de cobre (controle padrão e a testemunha absoluta. A suscetibilidade do isolado Xcv3 aos óleos testados foi avaliada na primeira etapa pela presença e ausência do crescimento bacteriano e, na segunda etapa, pela porcentagem de inibição do crescimento bacteriano. A análise da composição química dos óleos essenciais extraídos de L. gracilis, mostrou, o carvacrol (73,9 a 77% como composto majoritário e o timol (4,9 a 10,3%. Os óleos referentes aos tratamentos 01, 06 e 07 foram os que proporcionaram maiores porcentagens de inibição no crescimento bacteriano de Xcv: 94,75%, 96,50% e 94,02%, respectivamente, sendo superiores ao oxicloreto de cobre (49,6%.

  2. A Não Linearidade do Nexus Desenvolvimento Financeiro - Crescimento Económico: O caso dos países produtores de petróleo

    Directory of Open Access Journals (Sweden)

    José Alberto Fuinhas

    2016-06-01

    Full Text Available O presente estudo apresenta uma nova perspetiva da influência do Desenvolvimento Financeiro sobre o Crescimento Económico num painel de 15 países produtores de petróleo, com um período temporal de 1981 a 2011. Incorporou-se no modelo variáveis como as rendas de petróleo, o rácio de produção de petróleo sobre consumo de energia primária, preços de petróleo, exportações de bens e serviços, consumo de petróleo e emissões de CO2. Utilizou-se o modelo ARDL, para analisar as relações dinâmicas entre as variáveis no longo e no curto prazo. Seguidamente utilizou-se o estimador Driscoll-Kray, com efeitos fixos, para corrigir a significância dos parâmetros estimados. Os resultados demonstram a não linearidade no longo prazo, através do Teste U, entre Desenvolvimento Financeiro e Crescimento Económico nos estudos formulados. Devido ao longo período estudado, às variáveis incluídas e ao uso de técnicas econométricas adequadas, ampliou-se a literatura do nexus Desenvolvimento Financeiro-Crescimento Económico.

  3. The Leo Archipelago: A System of Earth-Rings for Communications, Mass-Transport to Space, Solar Power, and Control of Global Warming

    CERN Document Server

    Meulenberg, Andrew

    2010-01-01

    A multi-purpose low-earth-orbit system of rings circling the earth - the "LEO ARCHIPELAGO" - is proposed as a means of solving or bypassing many major problems hindering man's quest to get into space. A fiber-optic ring about the earth would be an initial testing and developmental stage for the ring systems, while providing cash-flow through a LEO-based, high-band-width, world-wide communication system. A Low-Earth-Orbit-based space-elevator system, "Sling-on-a-Ring," is proposed as the crucial developmental stage of the LEO Archipelago. Being a LEO-based heavy-mass lifter, rather than earth- or GEO-based, it is much less massive and therefore less costly than other proposed space-elevators. With the advent of lower-cost, higher-mass transport to orbit, the options for further space development (e.g., communications, space solar power, radiation dampers, sun shades, and permanent LEO habitation) are greatly expanded. This paper provides an update of the Sling-on-a-Ring concept in terms of new materials, poten...

  4. Preparação e caracterização de poliuretanos contendo diferentes quantidades de óleo de baru

    Directory of Open Access Journals (Sweden)

    Elizabeth Luiza de Almeida

    2016-01-01

    Full Text Available Resumo O óleo de baru (OB é uma matéria-prima renovável proveniente do cerrado brasileiro que possui elevado percentual de insaturação. O objetivo principal do trabalho foi o estudo das espumas de poliuretano com diferentes quantidade de óleo de baru saponificado. Os espectros de FTIR mostraram bandas representativas do poliol, óleo de baru e do pré-polímero. As curvas TG-DSC nas atmosferas de ar e N2 apresentaram perfis diferentes, devido a formação de produtos intermediários de oxidação dos materiais na atmosfera de ar. A quantidade de energia liberada pela DSC e as perdas de massa observadas pelas curvas TG indicaram saturação do óleo de baru na quantidade de 24,00% (m/m. Os gases liberados analisados por TG-DSC acoplado ao FTIR, foram: água, CO2, CO e etanol. Com o aumento do óleo de baru, ocorreu maior absorção de água pelo PU, na proporção de 29,00% (m/m o índice de intumescimento foi de 91,10%, em 1440 minutos. Assim, pudemos observer a formação do poliuretano com características distintas devido a presença do OB.

  5. Addressing challenges in combining GOES and LEO satellite products of the CONUS

    Science.gov (United States)

    Petersen, R. A.; Dworak, R.

    2012-12-01

    The challenges of transforming data from the next generation of satellites into information and products for the weather and science purposes presents a major challenge to both the research and applications communities. This will be especially difficult over land, where the process of integrating observations from multiple instruments and platforms in real time is complicated by the influence of the land surface on the observations themselves. In addition, effective merging of the mixture of time-continuous GEO and less frequent but higher spectral resolution LEO observations with other new surface-based observations will be essential and require new product processing strategies. The material shown in this presentation will begin to address some of these issues. It will describe results of efforts to inter-calibrate moisture products derived from existing GEO and LEO data sets over land designed 1) to identify and remove biases from the GOES moisture retrievals, 2) to determine the seasonally varying information content of the GOES relative to NWP model 'first guess' fields, 3) to determine the similarities and differences in error structures between GOES and AIRS retrievals, and 4) to determine the vertical structure of the errors in both systems. For example, comparisons have been made between GOES Total Precipitable Water (TPW) using the Li retrieval system (GOES-Li) and data from Raman Lidar (RL), Microwave Radiometer (MWR) and surface-based GPS-Met systems at the ARM CART site. The test showed for using one year of derived TPW products, the NWP model first guess (GFS) and GOES-Li products are wetter, however the GOES-Li beats the GFS in the warm season, especially in August when the NWP precipitation skill is least. During the warm season GOES-Li is noticeably better than GFS (which was too wet) during daytime. In addition, the GPS-Met data are best during the daytime, while the Ramon Lidar performs best at night. AIRS products were also evaluated for several

  6. Operational Impact of Improved Space Tracking on Collision Avoidance in the Future LEO Space Debris Environment

    Science.gov (United States)

    Sibert, D.; Borgeson, D.; Peterson, G.; Jenkin, A.; Sorge, M.

    2010-09-01

    Even if global space policy successfully curtails on orbit explosions and ASAT demonstrations, studies indicate that the number of debris objects in Low Earth Orbit (LEO) will continue to grow solely from debris on debris collisions and debris generated from new launches. This study examines the threat posed by this growing space debris population over the next 30 years and how improvements in our space tracking capabilities can reduce the number of Collision Avoidance (COLA) maneuvers required keep the risk of operational satellite loss within tolerable limits. Particular focus is given to satellites operated by the Department of Defense (DoD) and Intelligence Community (IC) in Low Earth Orbit (LEO). The following debris field and space tracking performance parameters were varied parametrically in the experiment to study the impact on the number of collision avoidance maneuvers required: - Debris Field Density (by year 2009, 2019, 2029, and 2039) - Quality of Track Update (starting 1 sigma error ellipsoid) - Future Propagator Accuracy (error ellipsoid growth rates - Special Perturbations in 3 axes) - Track Update Rate for Debris (stochastic) - Track Update Rate for Payloads (stochastic) Baseline values matching present day tracking performance for quality of track update, propagator accuracy, and track update rate were derived by analyzing updates to the unclassified Satellite Catalog (SatCat). Track update rates varied significantly for active payloads and debris and as such we used different models for the track update rates for military payloads and debris. The analysis was conducted using the System Effectiveness Analysis Simulation (SEAS) an agent based model developed by the United States Air Force Space Command’s Space and Missile Systems Center to evaluate the military utility of space systems. The future debris field was modeled by The Aerospace Corporation using a tool chain which models the growth of the 10cm+ debris field using high fidelity

  7. Effectiveness of Space Debris Mitigation Guidelines: Economic Potential of LEO and Traffic Management Issues

    Science.gov (United States)

    Belviso, Luciano

    implementation of international technical standards concerning traffic control systems. Applicability of regulatory regime to satellite tracking systems. Even considering the effectiveness of traffic control systems, the most part of accident will be caused by part of operating system floating without guidance. In this case, both the Outer Space Treaty[5] and the Liability Convention[6] only apply if the space object, or part of it, is identifiable. The improvement of tracking system will empower recognition capabilities and will allow to predict with a certain precision to what space object the debris belongs and, also considering the growing number of space objects, it will be possible to identify the fatherhood of a single debris with a certain confidence. The question concerning international law is whether an information relying on simulated and algorithm-based interpretation can be considered like an observed dataset. In other words, in the case one could identify a debris responsible for a damage using simulation, a standard for the whole identification procedure is needed in order to ensure a minimum requirement in terms of accuracy of the model used. These implications will be considered in our paper. References [1] Greenberg, Economic Implications of Orbital Debris Mitigation [LEO Missions], Proceedings of the 48th International Astronautical Congress, IAA-97-IAA-6.5.08, 1997 [2] Art. 33 of the International Telecommunication Convention (ITC) considers that the Geostationary Orbit is a "limited natural resource (which) must be used efficiently and economically so that countries or groups of countries may have equitable access [...]". [3] Collins and Williams, Towards traffic control systems for near-earth space, Proceedings of the 29th colloqium on the law of Outer Space, IISL, 1986, p.166. [4] Dittberner, Fudge, Huth, Johnson, McKnight, Examining siclifying assumption of probability of collisions in LEO, Proceedings of the first European conference on Space Debris

  8. Descripción de un caso de hiperplasia endometrial quística en una leona africana (Panthera leo) Description of a cystic endometrial hyperplasia case in an African lion (Panthera leo)

    OpenAIRE

    A.L. Migliorisi; A.T. Soto; M.V. Gómez; Laplace, R.; A. Massone

    2010-01-01

    En el presente trabajo, se describe un caso de hiperplasia endometrial quística en una leona africana (Panthera leo) de 13 años de edad aproximada, alojada en el Jardín Botánico y Zoológico de la ciudad de La Plata. El estudio anatómico, histopatológico y ultrasonográfico del aparato reproductor fueron realizados posteriormente a la ovariohisterectomía. Los principales hallazgos correspondieron a un proceso crónico de hiperplasia endometrial quística con infiltración linfoplasmocitaria, prese...

  9. Pathogenesis of two strains of lion (Panthera leo) morbillivirus in ferrets (Mustela putorius furo).

    Science.gov (United States)

    Evermann, J F; Leathers, C W; Gorham, J R; McKeirnan, A J; Appel, M J

    2001-05-01

    Canine distemper virus (CDV) was previously considered to have a host range restricted to the canid family. In 1994, the virus was associated with sporadic outbreaks of distemper in captive felids. However, after severe mortality occurred in the Serengeti lions (Panthera leo), attention became focused on the pathogenesis of the virus and a concerted effort was made to identify the virus as CDV or a closely related feline morbillivirus. The present study was designed to explore the susceptibility of ferrets to challenge with two morbilliviruses isolated from lions and the protective effects of a modified-live mink distemper vaccine. Because mortality in ferrets infected with pathogenic CDV approaches 100%, the ferret was selected as a test animal. Two strains of lion morbillivirus were used as a challenge, A92-27/20 (California lion isolate) and A94-11/13 (Serengeti lion isolate). The two strains of lion morbillivirus were antigenically related to CDV (Rockborn strain), and ferrets were susceptible to both of the viruses when inoculated intraperitoneally. The inoculated ferrets were anorectic at 5-6 days postinoculation (PI), exhibited oculonasal discharge at 9-12 days PI, and became moribund at 12-22 days PI. Severe bilateral conjunctivitis was the typical clinical sign. Inclusion bodies characteristic of morbillivirus (eosinophilic, intranuclear, and intracytoplasmic) were distributed in many epithelial cells, including those of the skin, conjunctiva, gallbladder, liver, pancreas, stomach, trachea, lung, urinary bladder, and kidney. Virus was reisolated from selected lung tissues collected at necropsy and identified by CDV-specific immunofluorescence. Ferrets vaccinated with the mink distemper vaccine (Onderstepoort strain) were protected from challenge with the two lion strains, adding further support to the premise that the viruses are closely related to CDV.

  10. Prey selection of lions Panthera leo in a small, enclosed reserve

    Directory of Open Access Journals (Sweden)

    R.J. Power

    2002-12-01

    Full Text Available Annual trends in numbers of ungulate species on a 15 km² reserve from 1993 to 1998, were evaluated in the context of lion Panthera leo reintroduction during 1996, and subsequent predation by them. The ungulate prey base was enumerated annually by aerial counts and a road count that took place during 1998. The lion prey record was obtained from direct observations of a radio-located pride of eight lions and daily reserve management records. All ungulate species that underwent precipituous declines were also the most important prey to lions, comprising over 80 % of their prey, and they were preyed upon according to their availability. Lion predation was causal for the declines in wildebeest Connochaetes taurinus, Blesbok Damaliscus pygargus phillipsi and Warthog Phacochoerus africana, while the decline in Kudu Tragelaphus strepsiceros was only partly ascribed to lions, as other non-lion related mortality sources were identified. The only ungulate species to increase subsequent to lion reintroduction was the Impala Aepyceros melampus, which was furthermore under-selected by lions. The uncontrolled population growth of Impala could have elicited ecological degradation, and it was advised to either not stock Impala, or otherwise control their numbers if lions are unable to do so. Lion hunting success and kill rate, were 21 % (n = 63 and 1 kill/4.4 days, respectively. Three bushpigs Potamochoerus larvatus were killed but not utilised,and this finding is corroborated by an intensive study in Kwazulu-Natal, and this aversion is discussed. Predators can cause unprecedented declines of their prey where the prey are confined to small reserves that have no refuge from predation. On an annual basis, prey may need to be augmented to sustain predators on small reserves

  11. Comparative skull analysis suggests species-specific captivity-related malformation in lions (Panthera leo.

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    Joseph Saragusty

    Full Text Available Lion (Panthera leo populations have dramatically decreased worldwide with a surviving population estimated at 32,000 across the African savannah. Lions have been kept in captivity for centuries and, although they reproduce well, high rates of stillbirths as well as morbidity and mortality of neonate and young lions are reported. Many of these cases are associated with bone malformations, including foramen magnum (FM stenosis and thickened tentorium cerebelli. The precise causes of these malformations and whether they are unique to captive lions remain unclear. To test whether captivity is associated with FM stenosis, we evaluated 575 lion skulls of wild (N = 512 and captive (N = 63 origin. Tiger skulls (N = 276; 56 captive, 220 wild were measured for comparison. While no differences were found between males and females or between subadults and adults in FM height (FMH, FMH of captive lions (17.36±3.20 mm was significantly smaller and with greater variability when compared to that in wild lions (19.77±2.11 mm. There was no difference between wild (18.47±1.26 mm and captive (18.56±1.64 mm tigers in FMH. Birth origin (wild vs. captive as a factor for FMH remained significant in lions even after controlling for age and sex. Whereas only 20/473 wild lions (4.2% had FMH equal to or smaller than the 5th percentile of the wild population (16.60 mm, this was evident in 40.4% (23/57 of captive lion skulls. Similar comparison for tigers found no differences between the captive and wild populations. Lions with FMH equal to or smaller than the 5th percentile had wider skulls with smaller cranial volume. Cranial volume remained smaller in both male and female captive lions when controlled for skull size. These findings suggest species- and captivity-related predisposition for the pathology in lions.

  12. Efficient Wideband Spectrum Sensing with Maximal Spectral Efficiency for LEO Mobile Satellite Systems

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    Feilong Li

    2017-01-01

    Full Text Available The usable satellite spectrum is becoming scarce due to static spectrum allocation policies. Cognitive radio approaches have already demonstrated their potential towards spectral efficiency for providing more spectrum access opportunities to secondary user (SU with sufficient protection to licensed primary user (PU. Hence, recent scientific literature has been focused on the tradeoff between spectrum reuse and PU protection within narrowband spectrum sensing (SS in terrestrial wireless sensing networks. However, those narrowband SS techniques investigated in the context of terrestrial CR may not be applicable for detecting wideband satellite signals. In this paper, we mainly investigate the problem of joint designing sensing time and hard fusion scheme to maximize SU spectral efficiency in the scenario of low earth orbit (LEO mobile satellite services based on wideband spectrum sensing. Compressed detection model is established to prove that there indeed exists one optimal sensing time achieving maximal spectral efficiency. Moreover, we propose novel wideband cooperative spectrum sensing (CSS framework where each SU reporting duration can be utilized for its following SU sensing. The sensing performance benefits from the novel CSS framework because the equivalent sensing time is extended by making full use of reporting slot. Furthermore, in respect of time-varying channel, the spatiotemporal CSS (ST-CSS is presented to attain space and time diversity gain simultaneously under hard decision fusion rule. Computer simulations show that the optimal sensing settings algorithm of joint optimization of sensing time, hard fusion rule and scheduling strategy achieves significant improvement in spectral efficiency. Additionally, the novel ST-CSS scheme performs much higher spectral efficiency than that of general CSS framework.

  13. Mycobacterium bovis infection in the lion (Panthera leo): Current knowledge, conundrums and research challenges.

    Science.gov (United States)

    Viljoen, Ignatius M; van Helden, Paul D; Millar, Robert P

    2015-06-12

    Mycobacterium bovis has global public-health and socio-economic significance and can infect a wide range of species including the lion (Panthera leo) resulting in tuberculosis. Lions are classified as vulnerable under the IUCN Red List of Threatened Species and have experienced a 30% population decline in the past two decades. However, no attempt has been made to collate and critically evaluate the available knowledge of M. bovis infections in lions and potential effects on population. In this review we set out to redress this. Arguments suggesting that ingestion of infected prey animals are the main route of infection for lions have not been scientifically proven and research is needed into other possible sources and routes of infection. The paucity of knowledge on host susceptibility, transmission directions and therefore host status, manifestation of pathology, and epidemiology of the disease in lions also needs to be addressed. Advances have been made in diagnosing the presence of M. bovis in lions. However, these diagnostic tests are unable to differentiate between exposure, presence of infection, or stage of disease. Furthermore, there are contradictory reports on the effects of M. bovis on lion populations with more data needed on disease dynamics versus the lion population's reproductive dynamics. Knowledge on disease effects on the lion reproduction and how additional stressors such as drought or co-morbidities may interact with tuberculosis is also lacking. Filling these knowledge gaps will contribute to the understanding of mycobacterial infections and disease in captive and wild lions and assist in lion conservation endeavours. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Efficient Wideband Spectrum Sensing with Maximal Spectral Efficiency for LEO Mobile Satellite Systems

    Science.gov (United States)

    Li, Feilong; Li, Zhiqiang; Li, Guangxia; Dong, Feihong; Zhang, Wei

    2017-01-01

    The usable satellite spectrum is becoming scarce due to static spectrum allocation policies. Cognitive radio approaches have already demonstrated their potential towards spectral efficiency for providing more spectrum access opportunities to secondary user (SU) with sufficient protection to licensed primary user (PU). Hence, recent scientific literature has been focused on the tradeoff between spectrum reuse and PU protection within narrowband spectrum sensing (SS) in terrestrial wireless sensing networks. However, those narrowband SS techniques investigated in the context of terrestrial CR may not be applicable for detecting wideband satellite signals. In this paper, we mainly investigate the problem of joint designing sensing time and hard fusion scheme to maximize SU spectral efficiency in the scenario of low earth orbit (LEO) mobile satellite services based on wideband spectrum sensing. Compressed detection model is established to prove that there indeed exists one optimal sensing time achieving maximal spectral efficiency. Moreover, we propose novel wideband cooperative spectrum sensing (CSS) framework where each SU reporting duration can be utilized for its following SU sensing. The sensing performance benefits from the novel CSS framework because the equivalent sensing time is extended by making full use of reporting slot. Furthermore, in respect of time-varying channel, the spatiotemporal CSS (ST-CSS) is presented to attain space and time diversity gain simultaneously under hard decision fusion rule. Computer simulations show that the optimal sensing settings algorithm of joint optimization of sensing time, hard fusion rule and scheduling strategy achieves significant improvement in spectral efficiency. Additionally, the novel ST-CSS scheme performs much higher spectral efficiency than that of general CSS framework. PMID:28117712

  15. Personality assessment and feline–keepers relationship in lions (Panthera leo

    Directory of Open Access Journals (Sweden)

    Giovanni Quintavalle Pastorino

    2016-06-01

    Full Text Available Animal personality is a growing research area due to the increasing evidence of the impact that it has on welfare, health and management of animals in captivity (Freeman and Gosling, 2010. Testing and improving existent methodologies, as well as develop new ones, to outline animal personality is an important step towards welfare, health and longevity of captive animals (Phillips, 2007; Whitham and Wielebnowski, 2013. Lions (Panthera leo were chosen for this study because the species is understudied compared to other felidae species in personality matters and because it displays a vast, diverse and well known behaviour repertoire (Schaller, 1973. Behavioural observations were conducted on the seven African lions housed in ZSL Whipsnade zoo. Keeper-animal interactions were recorded and a personality questionnaire was given to the keepers in order to rate 28 personality traits (Chadwick, 2014. Sociogram, composite sociality index (CSI and spread of participation index (SPI were also used to assess personality traits (Stanton 2015. Data gathered in this pilot study was successfully used to produce ID like personality traits profiles for all animals, to delineate personality traits, outline the unique characteristics of each subject. A sociogram consent to access and validate the dyad solitary/social and a SPI to understand each animal enclosure usage and relate it to the trait triad affiliate/fearful/aggressive towards humans. We believe this approach is promising and could be applied to investigate keeper-animal interactions also in other species. The limitation of this study is the sample size of the animal considered; in future research we hope to test other animals in order to validate the methodologies.

  16. Efficient Wideband Spectrum Sensing with Maximal Spectral Efficiency for LEO Mobile Satellite Systems.

    Science.gov (United States)

    Li, Feilong; Li, Zhiqiang; Li, Guangxia; Dong, Feihong; Zhang, Wei

    2017-01-21

    The usable satellite spectrum is becoming scarce due to static spectrum allocation policies. Cognitive radio approaches have already demonstrated their potential towards spectral efficiency for providing more spectrum access opportunities to secondary user (SU) with sufficient protection to licensed primary user (PU). Hence, recent scientific literature has been focused on the tradeoff between spectrum reuse and PU protection within narrowband spectrum sensing (SS) in terrestrial wireless sensing networks. However, those narrowband SS techniques investigated in the context of terrestrial CR may not be applicable for detecting wideband satellite signals. In this paper, we mainly investigate the problem of joint designing sensing time and hard fusion scheme to maximize SU spectral efficiency in the scenario of low earth orbit (LEO) mobile satellite services based on wideband spectrum sensing. Compressed detection model is established to prove that there indeed exists one optimal sensing time achieving maximal spectral efficiency. Moreover, we propose novel wideband cooperative spectrum sensing (CSS) framework where each SU reporting duration can be utilized for its following SU sensing. The sensing performance benefits from the novel CSS framework because the equivalent sensing time is extended by making full use of reporting slot. Furthermore, in respect of time-varying channel, the spatiotemporal CSS (ST-CSS) is presented to attain space and time diversity gain simultaneously under hard decision fusion rule. Computer simulations show that the optimal sensing settings algorithm of joint optimization of sensing time, hard fusion rule and scheduling strategy achieves significant improvement in spectral efficiency. Additionally, the novel ST-CSS scheme performs much higher spectral efficiency than that of general CSS framework.

  17. The evolutionary dynamics of the lion Panthera leo revealed by host and viral population genomics.

    Directory of Open Access Journals (Sweden)

    Agostinho Antunes

    2008-11-01

    Full Text Available The lion Panthera leo is one of the world's most charismatic carnivores and is one of Africa's key predators. Here, we used a large dataset from 357 lions comprehending 1.13 megabases of sequence data and genotypes from 22 microsatellite loci to characterize its recent evolutionary history. Patterns of molecular genetic variation in multiple maternal (mtDNA, paternal (Y-chromosome, and biparental nuclear (nDNA genetic markers were compared with patterns of sequence and subtype variation of the lion feline immunodeficiency virus (FIV(Ple, a lentivirus analogous to human immunodeficiency virus (HIV. In spite of the ability of lions to disperse long distances, patterns of lion genetic diversity suggest substantial population subdivision (mtDNA Phi(ST = 0.92; nDNA F(ST = 0.18, and reduced gene flow, which, along with large differences in sero-prevalence of six distinct FIV(Ple subtypes among lion populations, refute the hypothesis that African lions consist of a single panmictic population. Our results suggest that extant lion populations derive from several Pleistocene refugia in East and Southern Africa ( approximately 324,000-169,000 years ago, which expanded during the Late Pleistocene ( approximately 100,000 years ago into Central and North Africa and into Asia. During the Pleistocene/Holocene transition ( approximately 14,000-7,000 years, another expansion occurred from southern refugia northwards towards East Africa, causing population interbreeding. In particular, lion and FIV(Ple variation affirms that the large, well-studied lion population occupying the greater Serengeti Ecosystem is derived from three distinct populations that admixed recently.

  18. The evolutionary dynamics of the lion Panthera leo revealed by host and viral population genomics.

    Science.gov (United States)

    Antunes, Agostinho; Troyer, Jennifer L; Roelke, Melody E; Pecon-Slattery, Jill; Packer, Craig; Winterbach, Christiaan; Winterbach, Hanlie; Hemson, Graham; Frank, Laurence; Stander, Philip; Siefert, Ludwig; Driciru, Margaret; Funston, Paul J; Alexander, Kathy A; Prager, Katherine C; Mills, Gus; Wildt, David; Bush, Mitch; O'Brien, Stephen J; Johnson, Warren E

    2008-11-01

    The lion Panthera leo is one of the world's most charismatic carnivores and is one of Africa's key predators. Here, we used a large dataset from 357 lions comprehending 1.13 megabases of sequence data and genotypes from 22 microsatellite loci to characterize its recent evolutionary history. Patterns of molecular genetic variation in multiple maternal (mtDNA), paternal (Y-chromosome), and biparental nuclear (nDNA) genetic markers were compared with patterns of sequence and subtype variation of the lion feline immunodeficiency virus (FIV(Ple)), a lentivirus analogous to human immunodeficiency virus (HIV). In spite of the ability of lions to disperse long distances, patterns of lion genetic diversity suggest substantial population subdivision (mtDNA Phi(ST) = 0.92; nDNA F(ST) = 0.18), and reduced gene flow, which, along with large differences in sero-prevalence of six distinct FIV(Ple) subtypes among lion populations, refute the hypothesis that African lions consist of a single panmictic population. Our results suggest that extant lion populations derive from several Pleistocene refugia in East and Southern Africa ( approximately 324,000-169,000 years ago), which expanded during the Late Pleistocene ( approximately 100,000 years ago) into Central and North Africa and into Asia. During the Pleistocene/Holocene transition ( approximately 14,000-7,000 years), another expansion occurred from southern refugia northwards towards East Africa, causing population interbreeding. In particular, lion and FIV(Ple) variation affirms that the large, well-studied lion population occupying the greater Serengeti Ecosystem is derived from three distinct populations that admixed recently.

  19. Prevalence of Bartonella infection in wild African lions (Panthera leo) and cheetahs (Acinonyx jubatus).

    Science.gov (United States)

    Molia, S; Chomel, B B; Kasten, R W; Leutenegger, C M; Steele, B R; Marker, L; Martenson, J S; Keet, D F; Bengis, R G; Peterson, R P; Munson, L; O'Brien, S J

    2004-05-20

    Bartonella species are emerging pathogens that have been isolated worldwide from humans and other mammals. Our objective was to estimate the prevalence of Bartonella infection in free-ranging African lions (Panthera leo) and cheetahs (Acinonyx jubatus). Blood and/or serum samples were collected from a convenience sample of 113 lions and 74 cheetahs captured in Africa between 1982 and 2002. Whole blood samples available from 58 of the lions and 17 of the cheetahs were cultured for evidence of Bartonella spp., and whole blood from 54 of the 58 lions and 73 of the 74 cheetahs tested for the presence of Bartonella DNA by TaqMan PCR. Serum samples from the 113 lions and 74 cheetahs were tested for the presence of antibodies against Bartonella henselae using an immunofluorescence assay. Three (5.2%) of the 58 lions and one (5.9%) of the 17 cheetahs were bacteremic. Two lions were infected with B. henselae, based on PCR/RFLP of the citrate synthase gene. The third lion and the cheetah were infected with previously unidentified Bartonella strains. Twenty-three percent of the 73 cheetahs and 3.7% of the 54 lions tested by TaqMan PCR were positive for Bartonella spp. B. henselae antibody prevalence was 17% (19/113) for the lions and 31% (23/74) for the cheetahs. The prevalence of seropositivity, bacteremia, and positive TaqMan PCR was not significantly different between sexes and age categories (juvenile versus adult) for both lions and cheetahs. Domestic cats are thus no longer the only known carriers of Bartonella spp. in Africa. Translocation of B. henselae seronegative and TaqMan PCR negative wild felids might be effective in limiting the spread of Bartonella infection.

  20. Determinants of distribution patterns and management needs in a Critically Endangered lion Panthera leo population

    Directory of Open Access Journals (Sweden)

    Philipp Henschel

    2016-09-01

    Full Text Available The lion Panthera leo is Critically Endangered in West Africa and is known to occupy only four protected areas within the region. The largest population persists in the trans-boundary W-Arly-Pendjari (WAP ecosystem, in the border region of Benin, Burkina Faso, and Niger. WAP harbors an estimated 350 individuals, or 90% of West Africa’s lions. We modeled lion occupancy across WAP using systematic, vehicle-based spoor counts to assess how landscape variables related to biotic factors, management and human impact influence lion distribution across WAP. We surveyed 1110 km of roads across WAP in 2012, obtaining 79 lion detections in 32 of our 167 15 x 15 km sampling units (naïve occupancy = 0.41. Overall occupancy (Ψ was 0.71 (95% SE = 0.56-0.83 when accounting for imperfect detection (p = 0.22, 95% SE = 0.18-0.27. The best predictors of lion occupancy were numbers of permanent protected area staff and mean monthly dry season precipitation. Model-averaged estimates suggest greatest lion occupancy in the Arly and Pendjari management blocks, with lowest occupancy in the tri-national W National Park. Our results suggest that lions in WAP are equally limited by management and biotic factors, and demonstrate how unevenly distributed protection effort limits the distribution of an apex predator across a protected landscape. We strongly recommend increased funding and better protection to increase lion occupancy in WAP, most urgently in the W National Park.

  1. Hidrocarburos de petróleo, disueltos y dispersos, en cuatro ambientes costeros de Costa Rica

    Directory of Open Access Journals (Sweden)

    Jenaro Acuña-González

    2004-12-01

    Full Text Available Entre los años 2000 a 2002 se recolectaron y se analizaron 130 muestras de agua de mar en las costas de Costa Rica, para determinarles la concentración de hidrocarburos de petróleo disueltos y dispersos (HPDD, referida a equivalentes de criseno en hexano, y expresada como µg·L-1 . Se utilizó la técnica analítica de fluorescencia molecular. 42 muestras correspondieron al Caribe (Moín y 81 al Pacífico (Bahía Culebra, Golfo de Nicoya, Golfo Dulce y en una ocasión se tomaron muestras a lo largo del Estero de Puntarenas. En la zona costera de Moín el promedio de la concentración de HPDD fue 0.10 µg·L-1 , con una desviación estándar de ± 0.18 µg·L-1 , en un ámbito desde concentraciones no detectables por el método, (nd, hasta 0.65 µg·L-1 . En el Pacífico las concentraciones para todo el período del estudio, estuvieron entre nd y 0.37 µg·L-1 . En la Bahía Culebra no se detectaron HPDD en ninguna de las muestras (n = 12; en el Golfo de Nicoya el promedio y la desviación estándar fueron 0.04 µg·L-1 ± 0.09 µg·L-1 (n = 51, en un ámbito desde nd hasta 0.33 µg·L-1 . En el Golfo Dulce el promedio y la desviación estándar fueron 0.05 µg·L-1 ± 0.11 µg·L-1 (n = 18, en el ámbito desde nd a 0.37 µg·L-1 . Durante las fechas en que se llevó a cabo el muestreo, no se encontró una situación de contaminación por petróleo en los ecosistemas costeros estudiados, puesto que las concentraciones de HPDD no rebasaron el límite de 10 µg·L-1 referido a equivalentes de criseno, considerado típico de áreas oceánicas contaminadas. En Bahía Culebra fue la primera vez que se hizo el estudio de la contaminación por petróleo y se comprobó que en las fechas de muestreo la zona estuvo libre de esta contaminación. El promedio y la desviación estándar en el Estero de Puntarenas fueron 1.21 µg·L-1 ± 2.10 µg·L-1 (n = 7, en un ámbito de 0.17 a 5.91 µg·L-1 . Estos resultados evidenciaron una situación de contaminaci

  2. Period studies of classical Algol-type binaries II: UX Leo, RW Mon, EQ Ori, XZ UMa and AX Vul

    Science.gov (United States)

    Soydugan, F.; Erdem, A.; Doğru, S. S.; Aliçavuş, F.; Soydugan, E.; Çiçek, C.; Demircan, O.

    2011-07-01

    This study presents an investigation of the orbital period variations of five Algol type binaries, UX Leo, RW Mon, EQ Ori, XZ UMa and AX Vul based on all available minima times. The O- C diagrams of all systems exhibit a periodic variation superimposed on a downward parabolic segment. The mass loss due to magnetic braking effect in the cooler components is assumed to account for the parabolic variation with a downward shape, while it is suggested that the light-time effect (LITE) due to an unseen component around the eclipsing binaries explains the tilted sinusoidal changes in their O- C diagrams. The orbital period decrease rates for the systems are estimated as approximately between about 0.7 and 2.5 s per century. It is clearly seen that mass loss effect is more dominant than the expected mass transfer for classical Algols in this study. The minimum mass of the probable third bodies around the eclipsing pairs was calculated to be ⩽0.5 M ⊙ except for UX Leo, in which it was estimated to be approximately 0.9 M ⊙. In order to search for third lights in the light curves of five systems, the V-light curves of the systems were analyzed and their physical and photometric parameters were determined. For UX Leo, a significant third light contribution was determined. We found a very small third light that can be tested using multi-color light curves, for RW Mon, EQ Ori and XZ UMa, while a third light for AX Vul could not be exposed.

  3. Analysis of Electrical Power System Topology for LEO Satellites%LEO卫星电源系统拓扑研究

    Institute of Scientific and Technical Information of China (English)

    陈琦; 赵长江; 马亮

    2012-01-01

    Based on 30 low earth orbit (LEO) satellite missions and applications of electrical pow- er system, the comparison of five electrical power system topologies at system level is presented including configuration, principle, efficiency and devices. The maximum power point tracking (MPPT) buck-boost regulator (B2R)is selected as a flexible one because of its good compromise between regulating performances and composition cost. MPPT B2R fulfils LEO satellite require- ments and is one of widely applied electrical power systems, and the required reliability and modulari ty can been achieved by arranging power regulation module in hot redundancy. This topology provides a high level of flexibility and satisfies various Chinese LEO satellite mission needs.%基于30个近地轨道(LEO)卫星任务及其电源系统应用情况,在系统层面上对5种电源系统拓扑进行了分析比较,包括配置方式、控制原理、效率及器件等。针对功率调节性能和器件组成规模,选择配有最大功率点跟踪(MPPT)的升一降压调节器(B2R)作为多适用的电源系统拓扑。此系统适应LEO卫星需求,属于拓扑用途广泛的电源系统,可通过合理配置热备份的功率调节模块来实现功率组合及可靠性设计,具有较高的兼容性,能够满足中国LEO卫星任务需求。

  4. GEO-LEO BI-SAR imaging algorithm%GEO-LEO双基地SAR成像算法研究

    Institute of Scientific and Technical Information of China (English)

    董众; 徐卓异; 张善从

    2014-01-01

    A Doppler distribution weighted method is proposed to solve the two-dimensional spectrum of GEO-LEO Bi-SAR imaging system. Different from the existing methods,this method deduces the corresponding analytical expression according to the physical significance of weight factor and the orbital parameters of GEO-LEO satellites. The solution difficulty of the two-di-mensional spectrum expression was overcome without any introducing errors. In combination with an Inverse Scaled Fast Fourier Transformation algorithm,the accurate ground target imaging of GEO-LEO Bi-SAR was realized. The simulation results show the advantages of the imaging method proposed in the paper.%提出一种基于多普勒贡献比加权的GEO-LEO星载双基地SAR二维频谱求解方法,与现有的频谱求解方法不同,该方法根据加权因子的物理意义,并利用GEO-LEO的轨道参数推导其相应的解析表达式,在没有引入误差的情况下,解决了GEO-LEO双基地SAR的二维频谱表达式求解问题。并与二维尺度变换逆FFT成像算法结合,实现了GEO-LEO双基地SAR对地面目标的精确成像。仿真实验结果表明了算法的优越性。

  5. GESTÃO AMBIENTAL NAS EMPRESAS DO SETOR DE PETRÓLEO E GÁS EM MOSSORÓ-RN

    Directory of Open Access Journals (Sweden)

    Rayanne C. Oliveira

    2008-05-01

    Full Text Available Este trabalho constitui uma pesquisa de campo, na qual se estuda a gestão das ações em defesa do meio ambiente realizada nas empresas do setor de petróleo e gás natural e procura identificar a formação e o perfil profissional requeridos para o gestor ambiental nessa área. As atividades produtivas do setor de petróleo e gás geram elevado crescimento econômico para o município de Mossoró (RN. Contudo, grandes impactos ambientais estão aliados a esses processos, como: abertura de estradas, picadas e clareiras; danos à vegetação, solo e fauna; interferência nos recursos hídricos; geração de ruídos, explosões e vazamento de combustíveis e insegurança nas comunidades. Os impactos negativos dessas atividades vêm provocando das empresas, o uso de métodos e técnicas menos agressivos ao meio ambiente, principalmente, no cumprimento da legislação ambiental. O novo cenário evidencia que a proteção ambiental deixa de ser responsabilidade exclusiva dos órgãos oficiais de meio ambiente e passa a ser partilhada por todos os setores da sociedade, inclusive pelas empresas, cujos gestores passam a atuar na vanguarda de políticas públicas, capazes de “pensar global e agir local”, especialmente nessa região onde predominam potenciais riscos e impactos ao meio ambiente oriundos das atividades petrolíferas. Palavras-Chaves: gestão ambiental, setor produtivo, petróleo, gás natural, impacto ambientais.

  6. Doença do disco intervertebral em trabalhadores da perfuração de petróleo

    Directory of Open Access Journals (Sweden)

    Fernandes Rita de Cássia Pereira

    2000-01-01

    Full Text Available Estudo transversal em 1.026 trabalhadores em distrito de perfuração de petróleo do Nordeste brasileiro mostrou prevalência global de doença do disco intervertebral lombar de 5%, variando de 1,8% (atividades sem manuseio de carga, 4,5% (manuseio ocasional até 7,2% (manuseio habitual. Tal prevalência foi de 11,4% em operadores de sonda de perfuração de petróleo com mais de 40 anos de idade e de 10,5% naqueles com mais de 15 anos de empresa. A razão de prevalência (R.P. à associação entre trabalho em operação de sonda e doença do disco foi 2,3 (I.C. 95%: 1,3, 4,0. Para minimizar o efeito sobrevivência do trabalhador sadio foram usadas informações retrospectivas acerca da exposição. A informação referente à ocupação atual em lugar do histórico ocupacional resultaria em RP subestimada de 1,1 (I.C. 95%: 0,6, 1,9. A regressão logística ratificou os achados da análise tabular. Não houve confundimento nem interação. O incremento da indústria de petróleo no país e as alterações na gestão e contratação da força de trabalho implicam mudanças no gerenciamento de risco e controle de saúde, além de pronta intervenção ergonômica para controle da doença.

  7. Doença do disco intervertebral em trabalhadores da perfuração de petróleo

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Pereira Fernandes

    2000-09-01

    Full Text Available Estudo transversal em 1.026 trabalhadores em distrito de perfuração de petróleo do Nordeste brasileiro mostrou prevalência global de doença do disco intervertebral lombar de 5%, variando de 1,8% (atividades sem manuseio de carga, 4,5% (manuseio ocasional até 7,2% (manuseio habitual. Tal prevalência foi de 11,4% em operadores de sonda de perfuração de petróleo com mais de 40 anos de idade e de 10,5% naqueles com mais de 15 anos de empresa. A razão de prevalência (R.P. à associação entre trabalho em operação de sonda e doença do disco foi 2,3 (I.C. 95%: 1,3, 4,0. Para minimizar o efeito sobrevivência do trabalhador sadio foram usadas informações retrospectivas acerca da exposição. A informação referente à ocupação atual em lugar do histórico ocupacional resultaria em RP subestimada de 1,1 (I.C. 95%: 0,6, 1,9. A regressão logística ratificou os achados da análise tabular. Não houve confundimento nem interação. O incremento da indústria de petróleo no país e as alterações na gestão e contratação da força de trabalho implicam mudanças no gerenciamento de risco e controle de saúde, além de pronta intervenção ergonômica para controle da doença.

  8. Hematologia de tilápias-do-nilo alimentadas com dietas com óleos vegetais e estimuladas pelo frio

    Directory of Open Access Journals (Sweden)

    Daniel de Magalhães Araujo

    2011-03-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos de dietas com diferentes relações entre ácidos graxos poliinsaturados ômega-6 e ômega-3 nos parâmetros hematológicos e lipídeos plasmáticos de tilápias-do-nilo, antes e após estímulo pelo frio. Foram utilizados 320 alevinos invertidos para macho (±7,5 g, distribuídos aleatoriamente em 40 tanques (250 L e alimentados com oito dietas: basal (sem adição de óleo, 6% de óleo de girassol (OG, 5% de OG + 1% de óleo de linhaça (OL, 4% de OG + 2% OL, 3% de OG + 3% de OL, 2% de OG + 4% de OL, 1% de OG + 5% de OL e 6% de OL. Os parâmetros hematológicos e os lipídeos plasmáticos foram determinados ao final de 85 dias de cultivo e após três dias de estímulo pelo frio. Não houve efeito das dietas sobre nenhuma das variáveis analisadas no período anterior ao estímulo. O número de leucócitos foi reduzido em peixes alimentados com a dieta 6% de OL, após estímulo pelo frio. O estímulo pelo frio provocou um declínio do estado geral de saúde, como leucopenia. Tilápias-do-nilo alimentadas com dietas com 6% de OL apresentaram menor resistência ao frio.

  9. Notes on wild dog Lycaon pictus and lion Panthera leo population trends during a drought in the Kruger National Park

    Directory of Open Access Journals (Sweden)

    M.G.L. Mills

    1995-09-01

    Full Text Available Wild dog Lycaon pictus and lion Panthera leo populations in the Kruger National Park appeared to undergo an increase during a drought period in the early 1990s. Newly established packs, high adult survival and pup productivity contributed to an increase in the wild dog population and evidence for high predation success during the height of the drought is presented. An increase in the lion density between 1989 and 1993 on the northern basalt plains, as well as changes in the structure of the population, seem to be related to changes in prey populations, particularly to a decline in numbers and condition of buffalo Syncerus cafer.

  10. PURIFICAÇÃO DE ÓLEOS VEGETAIS POR EXTRAÇÃO COM CO2 SUPERCRÍTICO

    Directory of Open Access Journals (Sweden)

    Pedro L. M. PENEDO

    1997-12-01

    Full Text Available Este estudo constatou a possibilidade de extrairem-se ácidos graxos livres de óleos vegetais com CO2 supercrítico. Utilizou-se neste trabalho óleos de soja e de castanha do Pará. A pesquisa desenvolveu-se em duas etapas, inicialmente investigou-se a possibilidade de se extrairem os ácidos graxos destes óleos em condições de extração que variaram de 50-140 bar e de 40-80oC durante 40-160 minutos. Concluiu-se que é possível realizar a desacidificação de óleos vegetais. A eficiência da extração foi de aproximadamente 30% a 140 bar e 80oC para ambos os óleos. Após esta primeira etapa, o próximo passo foi a tentativa de obter-se um aumento na eficiência do processo promovendo a pré-degomagem nos óleos brutos como uma etapa anterior ao processo de desacidificação com CO2 supercrítico. A degomagem foi realizada através de dois métodos diferentes, um para extrair as gomas hidratáveis e outro para extrair tanto as hidratáveis como as não-hidratáveis. Os resultados experimentais foram obtidos a 140 bar e 80oC durante 40-160 minutos, mostrando que a pré-degomagem é realmente necessária, pois a eficiência da extração aumentou para 57% para o óleo de soja e 42% para o de castanha do Pará totalmente degomados, sendo que o método escolhido deve extrair tanto as gomas hidratáveis como as não-hidratáveis. Finalmente, utilizou-se cossolvente (etanol a 1-5% do peso do óleo para auxiliar a extração, observando-se um aumento na eficiência para aproximadamente 65% para o óleo de soja e 56% para o de castanha do Pará totalmente degomados a 140 bar e 80oC por 40-160 minutos.Purification of Vegetable Oils using Supercritical CO2. This work presents a study on the extraction of free fatty acids from crude soy and Brazil nut oils, using supercritical carbon dioxide. It was developed in two stages, at first moment we verified the possibility to extract free fatty acids from these oils and then the extraction conditions

  11. Biorremediación de suelos contaminados por derrames de hidrocarburos derivados del petróleo en Colombia

    OpenAIRE

    Petro Cardona, Piedad Helena; Mercado Montero, Gabriela Del Carmen

    2014-01-01

    Artículo de revisión como (requisito para optar el título de Ingeniero Químico).-- Universidad de San Buenaventura, Facultad de Ingenierías, Arquitectura, Artes y Diseño, Programa de Ingeniería Química, 2014 En la actualidad, uno de los principales problemas de contaminación de suelos, aire y agua, es el uso incorrecto de materiales y residuos peligrosos debido a la extracción y al manejo del petróleo en todos los países productores de hidrocarburos. El impacto ambiental que ha generado es...

  12. Potencial de manejo de Myzus persicae com óleo de pinhão manso armazenado em diferentes embalagens

    Directory of Open Access Journals (Sweden)

    Anderson Mathias Holtz

    2015-12-01

    Full Text Available Myzus persicae vem provocando prejuízos em diversas hortícolas. A utilização de inseticidas químicos vem proporcionando graves problemas na agricultura e meio ambiente. Métodos alternativos de controle têm-se tornado uma ferramenta eficaz no manejo de pragas, como a utilização de plantas inseticidas. Com o objetivo de reduzir e/ou substituir os agrotóxicos sintéticos por produtos ecologicamente corretos, este trabalho visou estudar a potencialidade inseticida do óleo de Jatropha curcas sobre o pulgão verde da couve, armazenado por 180 dias, em diferentes embalagens. Foram utilizados discos de folhas de couve contendo 10 pulgões, os quais foram imersos em solução de óleo de pinhão manso nas concentrações 0,0; 0,5; 1,0; 2,0 %. A mortalidade variou em função do tempo de armazenamento, concentração e do uso de diferentes tipos de recipientes, ocorrendo interação significativa entre esses fatores. Os polietilenos “pet branco”, “iogurte” e vidro de cor âmbar apresentaram maior mortalidade na concentração de 2 % ao longo do tempo, sendo que a maior mortalidade (99, 100 e 98 % foi obtida no período de 120, 150 e 60 dias de armazenamento, respectivamente. O polietileno “pet verde” também apresentou maior mortalidade na concentração de 2 % até os 150 dias. Essa foi de 100 % no tempo de armazenamento zero e de 14,6 % no tempo de 180 dias, demonstrando, nesse caso, que o tempo de armazenamento em garrafa “pet verde” interfere na ação do óleo sobre M. persicae. Conclui-se que óleo de pinhão manso, mesmo armazenado em diferentes recipientes ao longo do tempo, demonstra potencial no manejo de M. persicae. Palavras-chave: Myzus persicae. Jatropha curcas. Manejo alternativo.

  13. EcAMSat and BioSentinel: Autonomous Bio Nanosatellites Addressing Strategic Knowledge Gaps for Manned Spaceflight Beyond LEO

    Science.gov (United States)

    Padgen, Michael R.

    2017-01-01

    Manned missions beyond low Earth orbit (LEO) require that several strategic knowledge gaps about the effects of space travel on the human body be addressed. NASA Ames Research Center has been the leader in developing autonomous bio nanosatellites, including past successful missions for GeneSat, PharmaSat, and O/OREOS, that tackled some of these issues. These nanosatellites provide in situ measurements, which deliver insight into the dynamic changes in cell behavior in microgravity. In this talk, two upcoming bio nanosatellites developed at Ames, the E. coli Antimicrobial Satellite (EcAMSat) and BioSentinel, will be discussed. Both satellites contain microfluidic systems that precisely deliver nutrients to the microorganisms stored within wells of fluidic cards. Each well, in turn, has its own 3-color LED and detector system which is used to monitor changes in metabolic activity with alamarBlue, a redox indicator, and the optical density of the cells. EcAMSat investigates the effects of microgravity on bacterial resistance to antimicrobial drugs, vital knowledge for understanding how to maintain the health of astronauts in long-term and beyond LEO spaceflight. The behavior of wild type and mutant uropathic E. coli will be compared in microgravity and with ground data to help understand the molecular mechanisms behind antibiotic resistance and how these phenotypes might change in space. BioSentinel seeks to directly measure the effects of space radiation on budding yeast S. cerevisiae, particularly double strand breaks (DSB). While hitching a ride on the SLS EM-1 mission (Orion's first unmanned mission to the moon) in 2018, BioSentinel will be kicked off and enter into a heliocentric orbit, becoming the first study of the effects of radiation on living organisms outside LEO since the Apollo program. The yeast are stored in eighteen independent 16-well microfluidic cards, which will be individually activated over the 12 month mission duration. In addition to the wild

  14. Óleo de citronela no controle do carrapato de bovinos Citronella oil on the control of catle ticks

    Directory of Open Access Journals (Sweden)

    Clair Jorge Olivo

    2008-04-01

    Full Text Available O objetivo deste estudo foi avaliar o efeito in vivo e in vitro do óleo de citronela (Cymbopogon nardus (L. Rendle no carrapato de bovinos (Boophilus microplus. O óleo foi obtido de folhas frescas pelo processo de destilação e o rendimento foi de 0,7%. Para as experimentações in vitro foram usadas sete (0; 0,5; 1,0; 10,0; 25,0; 50,0; 100,0% e nove (0,1; 0,25; 0,5; 1,0; 2,0; 10,0; 25,0; 50,0; 100% concentrações de óleo de citronela, sendo testadas em fêmeas ingurgitadas. A eficácia observada foi de 0; 44,2; 92,1; 85,6; 87,8; 87,0; 88,9 e de 0,7; 2,8; 51,6; 79,3; 81,0; 87,1; 86,7; 89,5%, respectivamente. Os resultados sugerem que o óleo de citronela pode ser usado no controle do carrapato bovino.This research was aimed at evaluating in vitro and in vivo effects of citronella (Cymbopogon nardus (L. Rendle oil on catle ticks. The volatile oil was obtained from de fresh leaves of citronella grass by steam destilation and the yelds was 0.7%. Seven (0; 0.5; 1.0; 10.0; 25.0; 50.0; 100.0% and nine (0.1; 0.25; 0.5; 1.0; 2.0; 10.0; 25.0; 50.0; 100.0% concentrations of citonella oil were used on in vitro trials with engorged female ticks. The efficacy control ticks was 0; 44.2; 92.1; 85.6; 87.8; 87.0; 88.9 and 0; 0.7; 2.8; 51.6; 79.3; 81.0; 87.1; 86.7 89.5 %, respectively. These sugest that the citronella oil can be practical used for controlling of catle ticks.

  15. Revisando el impacto fiscal de la suba de los precios del petróleo en Centroamérica

    OpenAIRE

    Fernando Navajas; Marcelo Catena

    2011-01-01

    Se caracteriza la naturaleza y magnitud del shock del precio del petróleo sobre las economías centroamericanas entre 2003 y 2010, y se estima el efecto sobre la balanza comercial (el ingreso equivalente) descomponiendo el mismo para observar el rol de precios, márgenes e impuestos. El shock alcanzó su climax en 2008 con un efecto-impacto del 8% del PIB sobre las economías en promedio (algo menos del 5% para Guatemala y 14% para Nicaragua). Este shock ser revirtió con la crisis de 2008-09 pero...

  16. Efeito de óleos essenciais sobre o crescimento e produção de aflatoxinas por Aspergillus flavus

    OpenAIRE

    Alessandra Marcon Gasperini

    2014-01-01

    Resumo: O fungo Aspergillus flavus é responsável pela degradação de alimentos, além de produzir aflatoxinas que são reconhecidas como potentes carcinógenos. Atualmente, frente ao aumento acelerado de cepas resistentes aos antifúngicos sintéticos e à pressão dos consumidores pela substituição destes por produtos naturais, a busca de novos antimicrobianos a partir de óleos essenciais (OE) tem se tornado uma opção promissora. Neste contexto, o objetivo deste trabalho foi avaliar a capacidade de ...

  17. A participação de Fletcher no experimento da gota de óleo de Millikan

    OpenAIRE

    Santos, Carlos Alberto dos

    1995-01-01

    O famoso experimento da gota de óleo, com o qual Millikan obteve valores altamente precisos para a carga do elétron, desempenhou papel importante para a concessão do seu Prêmio Nobel. O primeiro trabalho referente a essa série de medidas teve a assinatura solitária de Millikan, apesar da reconhecida participação do seu estudante Fletcher. A partir de uma nota autobiográfica de Fletcher, fica-se sabendo que ele foi o responsável pela construção do primeiro equipamento para o referido experimen...

  18. Biorremediación de suelos contaminados por derrames de hidrocarburos derivados del petróleo en Colombia

    OpenAIRE

    Petro Cardona, Piedad Helena; Mercado Montero, Gabriela Del Carmen

    2014-01-01

    Artículo de revisión como (requisito para optar el título de Ingeniero Químico).-- Universidad de San Buenaventura, Facultad de Ingenierías, Arquitectura, Artes y Diseño, Programa de Ingeniería Química, 2014 En la actualidad, uno de los principales problemas de contaminación de suelos, aire y agua, es el uso incorrecto de materiales y residuos peligrosos debido a la extracción y al manejo del petróleo en todos los países productores de hidrocarburos. El impacto ambiental que ha generado es...

  19. Óleos e extratos vegetais no controle da ferrugem asiática da soja (Glycine max (L.) Merril.)

    OpenAIRE

    Borges, Daniella Ines

    2007-01-01

    A agricultura atual tem aumentado o seu potencial de produção graças à aplicação de produtos químicos para o controle de pragas e de doenças de plantas, o que tem causado sérios prejuízos ao meio ambiente e à saúde do agricultor. A exploração da atividade biológica de compostos secundários de plantas pode constituir mais uma forma potencial de controle alternativo, reduzindo, assim, o impacto ambiental. Portanto, este trabalho teve por objetivo selecionar extratos e óleos essenciais vegetais ...

  20. Cultivo intercalares em fase inicial de desenvolvimento e desempenho produtivo de cultivares de palma de óleo em diferentes ambientes de Roraima

    OpenAIRE

    Antonia Dianaia de Oliveira Lopes

    2014-01-01

    A expansão da cultura da palma de óleo nas áreas já desflorestadas da Amazônia legal é reconhecida como uma excelente alternativa para a produção de óleo para fins alimentícios e energéticos. O estado de Roraima apresenta as condições edafoclimáticas adequadas para seu desenvolvimento e introdução na estrutura da agricultura familiar. Objetivou-se com este trabalho desenvolver sistemas de cultivos nas entrelinhas da palma de óleo em área de floresta alterada, durante o período inicial de dese...