Science.gov

Sample records for acta historica astronomiae

  1. Beitraege zur Astronomiegeschichte, Band 5 (Acta Historica Astronomiae Vol. 18)

    NASA Astrophysics Data System (ADS)

    Duerbeck, H. W.; Dick, W. R.; Hamel, J.

    2003-01-01

    The 18th volume of the Acta Historica Astronomiae is at the same time the sixth collection of essays on the history of astronomy ("Beitræge zur Astronomiegeschichte, Band 6"), edited by the historians of astronomy W.R. Dick (Potsdam) and J. Hamel (Berlin). Besides a few short notices and book reviews, the book contains eight major articles, which deal with astronomical topics covering the time from the 16th to the 19th centuries. The first article by Michael Weichenhan (Berlin) deals with "the invention of the disk-shaped earth: a chapter of Copernican apologetics". The author shows that the concept of a "disc-shaped Earth" was by no means widespread in the middle ages, but restricted to the father of the church Lactantius and some adherents. Nevertheless, it was used by adherents of Copernicus to show the absurd consequences of a strictly literal biblical interpretation -- here concerning the Earth's shape, disc versus sphere, there the geocentric versus the heliocentric system. This thorough philosophical study is followed by two very short articles. "The measuring accuracy of Tycho's large sextant" by Johann Wünsch investigates O-C values of planet-star distances, as based on Tycho's observations as published in the Historia Coelestis (a compilation, which is also based on Tycho's manuscripts, and published in Regensburg in 1672). The result is that standard deviations are 80 arcseconds for Saturn and 89 arcseconds for Jupiter and Mars, an unexpectedly poor result in view of the general opinion that Tycho was famous for his precision work. "The astronomer Christoph Grienberger and the Galilei trial" by Franz Daxecker deals with a Jesuit astronomer who was both the disciple and successor of the mathematician-astronomer Christopher Clavius at the Collegium Romanum. While he was inclined to Galilei early on, he was forced to propagate Aristotelian doctrine. The brief article is very concise, but extremely tiresome to read (3 pages of pure text are embellished by

  2. Publications on Albert Einstein, cosmology and theory of relativity in Acta Historica Astronomiae. An annotated bibliography. (German Title: Publikationen zu Albert Einstein, Kosmologie und Relativitätstheorie in Acta Historica Astronomiae. Eine annotierte Bibliographie)

    NASA Astrophysics Data System (ADS)

    Dick, Wolfgang R.

    This bibliography lists 15 publications which appeared in volumes 1 to 26 (1998 to 2005) in the series ``Acta Historica Astronomiae''. They concern life and work of Albert Einstein as well as the history of and modern developments in the theory of relativity and relativistic cosmology.

  3. Book Review: Beitraege zur Astronomiegeschichte, Band 5 (Acta Historica Astronomiae Vol. 15)

    NASA Astrophysics Data System (ADS)

    Duerbeck, H. W.; Dick, W. R.; Hamel, J.

    2002-12-01

    The 15th volume of the Acta Historica Astronomiae is at the same time the fifth collection of essays on the history of astronomy (Beitraege zur Astronomiegeschichte, Band 5), edited by the historians of astronomy W.R. Dick (Potsdam) and J. Hamel (Berlin). Besides a few short notices and book reviews, the book contains 11 major articles, which deal with astronomical topics covering the time from the 16th to the 20th centuries. The first article, on the analysis and interpretation of historical horoscopes as a source of the history of science, is based on the inaugural lecture of its author, Guenther Oestmann. After a general introduction, which deals with the principles of horoscope making, the author discusses the horoscope of Count Heinrich Ranzau (1526-1598), the Danish governor of Schleswig-Holstein, who was a friend of Tycho Brahe. Oestmann shows that the astronomical-mathematical basis of such a horoscope can be reconstructed and interpreted. However, it is hardly possible to gain an insight in the process how the interpretation of a horoscope was done in detail. The second and third articles, by Franz Daxecker, deal with Athanasius Kircher and Christoph Scheiner, two catholic astronomers of the 17th century. Kircher's Organum Mathematicum is a calculating device that can be used in the fields of arithmetic, geometry, chronology, astronomy, astrology and others. The author provides extracts of the description of the Organum taken from a book by Caspar Schott, which deal with chronology and astronomy. A photograph of the Organum indicates that this tool consists of a set of tables glued on wooden or cardboard, but details of its contents and applications remain pretty obscure for the reader - a few elaborated examples would have been helpful. The second paper deals with the life of Christoph Scheiner SJ, the co-discoverer of sunspots (next to Galileo), after leaving Rome in 1633 - the year of the Galileo trial. Scheiner spent his later years in the Austrian and

  4. Book Review: Beitraege zur Astronomiegeschichte, Band 5 (Acta Historica Astronomiae Vol. 15)

    NASA Astrophysics Data System (ADS)

    Duerbeck, H. W.; Dick, W. R.; Hamel, J.

    2002-12-01

    The 15th volume of the Acta Historica Astronomiae is at the same time the fifth collection of essays on the history of astronomy (Beitraege zur Astronomiegeschichte, Band 5), edited by the historians of astronomy W.R. Dick (Potsdam) and J. Hamel (Berlin). Besides a few short notices and book reviews, the book contains 11 major articles, which deal with astronomical topics covering the time from the 16th to the 20th centuries. The first article, on the analysis and interpretation of historical horoscopes as a source of the history of science, is based on the inaugural lecture of its author, Guenther Oestmann. After a general introduction, which deals with the principles of horoscope making, the author discusses the horoscope of Count Heinrich Ranzau (1526-1598), the Danish governor of Schleswig-Holstein, who was a friend of Tycho Brahe. Oestmann shows that the astronomical-mathematical basis of such a horoscope can be reconstructed and interpreted. However, it is hardly possible to gain an insight in the process how the interpretation of a horoscope was done in detail. The second and third articles, by Franz Daxecker, deal with Athanasius Kircher and Christoph Scheiner, two catholic astronomers of the 17th century. Kircher's Organum Mathematicum is a calculating device that can be used in the fields of arithmetic, geometry, chronology, astronomy, astrology and others. The author provides extracts of the description of the Organum taken from a book by Caspar Schott, which deal with chronology and astronomy. A photograph of the Organum indicates that this tool consists of a set of tables glued on wooden or cardboard, but details of its contents and applications remain pretty obscure for the reader - a few elaborated examples would have been helpful. The second paper deals with the life of Christoph Scheiner SJ, the co-discoverer of sunspots (next to Galileo), after leaving Rome in 1633 - the year of the Galileo trial. Scheiner spent his later years in the Austrian and

  5. BOOK REVIEW: Astronomie von Olbers bis Schwarzschild. Nationale Entwicklungen und internationale Beziehungen im 19. Jahrhundert (Acta Historica Astronomiae Vol. 16)

    NASA Astrophysics Data System (ADS)

    Sterken, C.; Dick, W. R.; Hamel, J.

    2002-12-01

    The 14th volume of the Acta Historica Astronomiae is the Proceedings of a Colloquium International Relationships in Astronomy (in German) organised by the History of Astronomy Section of the Astronomische Gesellschaft held on September 18 in Lilienthal, Germany. The book contains 13 articles on astronomical topics covering the 19th and 20th centuries. The first paper is by Guenther Oestmann and deals with contemporary assessments of Johann Hieronymus Schroeter's (1745-1816) astronomical works and with later judgements of the scientific importance and significance of his observations as seen by astronomers and historians. This report is complemented by a second article on Schroeter's 25-ft reflector in Lilienthal near Bremen. To this end, author Felix Luehning has constructed a scale model of the telescope, and shows how the building of a model brings a deeper understanding of function and handling of this instrument. This brings us to a third paper on telescope building in Lilienthal: Hans-Joachim Leue describes the cooperation of Johann Hieronymus Schroeter and Johann Gottlieb Schrader in developing a white reflecting metal alloy for use as telescope mirror. The fourth article, by Klaus Schillinger, describes on the basis of archival documents the aquisition history of the Herschel telescopes, including telescope quality check, repair and building. Memorial sites referring to Wilhelm Olbers, Johann Hieronymus Schroeter, Friedrich Wilhelm Bessel and Carl Friedrich Gauss are described by Arno Langkavel in two walks outlined in the very last paper of this book. Peter Brosche, in the fifth paper, discusses the rediscovery of Ceres in December1801, a discovery that was the result of the combined efforts of a theoretician (Gauss) and an observer (Zach). Juergen Hamel's paper is based on previously unused archival sources and discusses the outstanding role played by H. C. Schumacher (1780-1850, editor of the Astronomische Nachrichten) in the communication between

  6. "Paedagogica Historica": Trendsetter or Follower?

    ERIC Educational Resources Information Center

    Rogers, Rebecca

    2014-01-01

    This article considers the role "Paedagogica Historica" has played in stimulating new approaches in the history of education within the international community since the emergence of the new series in 1900. Particular focus is placed on the volumes published in the wake of ISCHE (International Standing Conference in the History of…

  7. Astronomia Motivadora no Ensino Fundamental

    NASA Astrophysics Data System (ADS)

    Melo, J.; Voelzke, M. R.

    2008-09-01

    O objetivo principal deste trabalho é procurar desenvolver o interesse dos alunos pelas ciências através da Astronomia. Uma pesquisa com perguntas sobre Astronomia foi realizada junto a 161 alunos do Ensino Fundamental, com o intuito de descobrir conhecimentos prévios dos alunos sobre o assunto. Constatou-se, por exemplo, que 29,3% da 6ª série responderam corretamente o que é eclipse, 30,0% da 8ª série acertaram o que a Astronomia estuda, enquanto 42,3% dos alunos da 5ª série souberam definir o Sol. Pretende-se ampliar as turmas participantes e trabalhar, principalmente de forma prática com: dimensões e escalas no Sistema Solar, construção de luneta, questões como dia e noite, estações do ano e eclipses. Busca-se abordar, também, outros conteúdos de Física tais como a óptica na construção da luneta, e a mecânica no trabalho com escalas e medidas, e ao utilizar uma luminária para representar o Sol na questão do eclipse, e de outras disciplinas como a Matemática na transformação de unidades, regras de três; Artes na modelagem ou desenho dos planetas; a própria História com relação à busca pela origem do universo, e a Informática que possibilita a busca mais rápida por informações, além de permitir simulações e visualizações de imagens importantes. Acredita-se que a Astronomia é importante no processo ensino aprendizagem, pois permite a discussão de temas curiosos como, por exemplo, a origem do universo, viagens espaciais a existência ou não de vida em outros planetas, além de temas atuais como as novas tecnologias.

  8. 1. HistoricaAmerican Buildings Survey John O. Brostrup, Photographer March 4, ...

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

    1. HistoricaAmerican Buildings Survey John O. Brostrup, Photographer March 4, 1937 1:30 P.M. VIEW FROM SOUTHEAST (front). - National Zoological Park, Holt House, Adams Mill Road Vicinity, Washington, District of Columbia, DC

  9. Lo Gnomone Clementino Astronomia Meridiana in Basilica

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2014-05-01

    Costruito per chiara volontà del papa 70 anni dopo il caso Galileo, lo Gnomone Clementino è un grande telescopio solare che non fa uso di lenti a 92 anni dall’invenzione del cannocchiale. Queste due caratteristiche basterebbero da sole a giustificare l’interesse verso questo strumento. L’astronomia meridiana è alla base dell’astrometria e dell’astrofisica moderna. Lo Gnomone Clementino sta oggi all’astronomia, come il veliero “Amerigo Vespucci” sta alla Marina Italiana. E’ possibile svolgere ogni genere di osservazione e studio su questo strumento, e dal 2002 vi tengo lezioni teorico-pratiche del corso di Storia dell’Astronomia e La Terra nel Sistema Solare della Sapienza, Università di Roma, Facoltà di Lettere e Filosofia. Questo testo aggiunge alcuni tasselli alla ricerca storica sulla meridiana, appoggiandosi, com’è naturale, sulle spalle di giganti che mi hanno preceduto in questi studi. In particolare la misura dell’azimut della meridiana, ed il suo inquadramento tra gli strumenti simili ed alcuni studi di astrometria sui dati del 1701-1703 di Bianchini, che sono apparsi fin’ora soltanto su riviste specializzate ed in Inglese vengono qui proposti in Italiano e semplificati, per valorizzare sempre più questa straordinaria opera d’arte e di scienza.

  10. Acta Astronautica: 60 years of excellence

    NASA Astrophysics Data System (ADS)

    Chern, Rock Jeng-Shing; Chang, Eva Yi-Wei

    2014-12-01

    The Acta Astronautica is 60 years old [1]. Ever since its first publication in 1955 with the title Astronautica Acta (from 1955 to 1973), 2014 is the 60th year of Acta Astronautica (from 1955 to present). Fig. 1 is a poster to manifest the remarkable milestone during the 65th IAC held in Toronto, Canada on 29 September to 3 October 2014. Under the auspices of the IAA's Publications and Communication Committee, and the seamless cooperation and strong support of IAA, Editor-in-Chief, Co-Editors, Managing Editor, authors, reviewers, readers, publisher and all IAA Academicians, its impact factor and ranking have significant improvements recently. Fig. 2 shows the increase in impact factor from 2008 to 2013. The ranking is 7 out of the 63+ journals in the category of Aerospace Engineering.

  11. V Olimpíada Brasileira de Astronomia

    NASA Astrophysics Data System (ADS)

    Villas da Rocha, J. F.; Canalle, J. B. G.; Wuesnche, C. A.; de Medeiros, J. R., Silva, A. V. R.; Lavouras, D. F.; Dottori, H. A.; Maia, M. A. G.; Vieira Martins, R.; Poppe, P. C. R.

    2003-08-01

    Neste trabalho apresentamos os resultados da V Olimpíada Brasileira de Astronomia, a qual ocorreu em 11/05/2002 em todos os estabelecimentos de ensino fundamental ou médio previamente cadastrados. Participaram do evento 60.338 alunos distribuídos por 1469 escolas pertencentes a todos os Estados brasileiros. Uma equipe de 5 alunos foi escolhida para representar o Brasil na VII Olimpíada Internacional de Astronomia que ocorreu na Rússia em 2002 e dois de nossos alunos ganharam a medalha de bronze naquele evento.

  12. Astronomia.pl: Portal activity in 2006-2007

    NASA Astrophysics Data System (ADS)

    Czart, K.; Pomierny, J.

    2008-06-01

    We present the latest activity of Astronomia.pl - the Polish Astronomy Portal, the most popular internet portal about astronomy in Poland. Astronomia.pl is a wide-ranging portal, covering news, a database of articles, books, lectures, an astronomical calendar, a newsletter, a virtual library of diploma theses, a discussion forum, chat, galleries, a catalogue of websites and other services. The portal also owns several additional services like an on-line lexicon with biographies of astronomers, a website about Polish planetariums and a server for websites created by astronomy amateurs. There is also small part of the portal in English.

  13. Intracellular Induction of Listeria monocytogenes actA Expression

    PubMed Central

    Shetron-Rama, Lynne M.; Marquis, Hélène; Bouwer, H. G. Archie; Freitag, Nancy E.

    2002-01-01

    Following entry into the host cytosol, the bacterial pathogen Listeria monocytogenes dramatically increases the expression of several key virulence factors. The expression of actA, whose protein product is required for L. monocytogenes actin-based intracellular motility, is increased by more than 200-fold in cytosolic bacteria in comparison to broth-grown cultures. Two distinct promoter elements have been reported to regulate actA expression. One promoter is located immediately upstream of actA coding sequences, while the second promoter is contributed by the upstream mpl gene via the generation of an mpl-actA-plcB transcript. A series of L. monocytogenes mutants were constructed to define the contributions of individual promoter elements to actA expression. The intracellular induction of actA expression was found to be dependent upon the actA proximal promoter; the mpl promoter appeared to contribute to the extracellular induction of actA but did not affect intracellular levels of expression. The actA promoter is dependent upon a regulatory factor known as PrfA for transcriptional activation; however, no increase in actA expression was detected following the introduction of a high-affinity PrfA binding site within the actA promoter. The presence of a mutationally activated form of PrfA, known as PrfA*, increased overall actA expression in broth-grown cultures of both wild-type and actA promoter mutant strains, but the levels of induction observed were still approximately 50-fold lower than those observed for intracellularly grown L. monocytogenes. Collectively, these results indicate that the dramatic induction of actA expression that occurs in the host cell cytosol is mediated through a single promoter element. Furthermore, intracellular induction of actA appears to require additional steps or factors beyond those necessary for the activation and binding of PrfA to the actA promoter. PMID:11854187

  14. Marking the 400th Anniversary of Kepler's Astronomia nova

    NASA Astrophysics Data System (ADS)

    Mahoney, T. J.

    2010-11-01

    Special Session 9 of the XXVII General Assembly (11-14 August 2009, Rio de Janeiro) was devoted to the topic “Marking the 400th Anniversary of Kepler's Astronomia nova”. During the two-and-a-half day meeting (spread over four days), there were nine invited and three contributed talks, a round-table discussion on the future of Kepler studies and an open session to propose the setting up of a Johannes Kepler Working Group under the aegis of the IAU.

  15. Entering the 60th year of Acta Astronautica

    NASA Astrophysics Data System (ADS)

    Chang, Yi-Wei; Chern, Jeng-Shing; Marec, Jean-Pierre

    2014-04-01

    The Acta Astronautica Journal was firstly published in 1955 as the official Journal of the International Astronautical Federation (IAF) with the title Astronautica Acta. It is entering its 60th year in 2014. In 1962, the Astronautica Acta became the official Journal of the International Academy of Astronautics (IAA) established in 1960. A total of 18 volumes had been published from 1955 to 1973 under the leadership of three Editor-in-Chiefs: F. Hecht, Theodore von Karman, and Martin Summerfield. In 1974, A.K. Oppenheim became the new Editor-in-Chief and several evolved changes were performed including change of the title to Acta Astronautica (for grammatical correctness), cover page change, and format change. From 1974 to 2010, another three Editor-in-Chiefs led the journal with 67 volumes published. They were A.K. Oppenheim, Jean-Pierre Marec, and Rupert Gerzer. The current Editor-in-Chief Jeng-Shing Chern (Rock) took over the job from 2011. Total pages and articles published in 2012 are 3586 and 356, respectively. Currently, the Acta Astronautica Editorial Board consists of one Editor-in-Chief, 15 Co-Editors, one Managing Editor and one Honorary Editor-in-Chief (Jean-Pierre Marec). After 59 years, the Acta Astronautica has become a well-known journal worldwide. Its current rank and impact factor are 7/63 and 0.701, respectively. This paper presents some of the details as well as new strategies and steps. In particular, supports from the IAA Academicians are mandatory and most welcome.

  16. Elsevier/Spectrochimica Acta Atomic Spectroscopy Award 2014

    NASA Astrophysics Data System (ADS)

    Omenetto, Nicolo'; de Loos, Greet

    2016-03-01

    This is to announce the 2014 Elsevier/Spectrochimica Acta Award, the annual award honoring the most significant article(s) published in a volume. Elsevier makes this award on behalf of Spectrochimica Acta, Part B, to encourage the publication of top articles in this journal. All papers published during one year are considered for this award and the Editorial Advisory Board and the Guest Editor(s) of the special issue(s) are responsible for the selection. The award consists of a monetary prize of 1000 together with a presentation certificate.

  17. Elsevier/Spectrochimica Acta Atomic Spectroscopy Award 2013

    NASA Astrophysics Data System (ADS)

    Omenetto, Nicolo'; de Loos, Greet

    2015-01-01

    This is to announce the 2013 Elsevier/Spectrochimica Acta Award, the annual award honoring the most significant article(s) published in a volume. Elsevier makes this award on behalf of Spectrochimica Acta, Part B, to encourage the publication of top articles in this journal. All papers published during one year are considered for this award and the Editorial Advisory Board and the Guest Editor(s) of the special issue(s) are responsible for the selection. The award consists of a monetary prize of 1000 together with a presentation certificate.

  18. Citation Analysis of "Geochimica et Cosmochimica Acta," 1951-1960.

    ERIC Educational Resources Information Center

    Lifshin, Arthur

    1993-01-01

    A citation analysis of the first 10 years of "Geochimica et Cosmochimica Acta" from 1951 to 1960 is described. A shift from German to English language citations and the emerging importance of the journal in the field, which is undergoing a change resulting from technological innovation, are shown. Tables and graphs are included. (EAM)

  19. Localization of the ActA polypeptide of Listeria monocytogenes in infected tissue culture cell lines: ActA is not associated with actin "comets".

    PubMed Central

    Niebuhr, K; Chakraborty, T; Rohde, M; Gazlig, T; Jansen, B; Köllner, P; Wehland, J

    1993-01-01

    The ActA protein of the gram-positive pathogen Listeria monocytogenes is a 90-kDa polypeptide required for interaction of the bacteria with components of the host cell microfilament system to generate intra- and intercellular movement. To study the localization, distribution, and expression of the ActA polypeptide in L. monocytogenes grown either in broth culture or in infected tissue culture cells, we first isolated ActA by monoclonal antibody-based immunoaffinity chromatography. Polyclonal rabbit antisera raised against purified ActA revealed that ActA was associated with the cell wall and exposed on the surface of the bacteria, readily accessible to ActA antibodies. In contrast, a C-terminally truncated ActA1 polypeptide expressed by the isogenic actA1 mutant was detected only in the supernatant fluids. Immunofluorescence microscopy and electron microscopic studies using immunogold labeling showed that ActA was present on the surface of the bacteria infecting PtK2 and J774 cells at all stages of the infection cycle and was not found to be associated with the actin "tail" of individual bacteria. For the isogenic actA1 mutant strain, which grew as microcolonies within infected cells, only diffuse staining of the secreted ActA1 polypeptide in the host cytoplasm was observed. The ActA polypeptide therefore appears to be required in the initiation of actin accumulation by the bacterium and is apparently not directly involved in the generation of the actin tail. Analysis of strains of several L. monocytogenes serotypes indicated microheterogeneity in the molecular weights of the ActA polypeptides of individual strains and led to the detection of a serotype 3a strain that does not produce ActA. Images PMID:8514381

  20. Aortic Disease Presentation and Outcome Associated with ACTA2 mutations

    PubMed Central

    Regalado, Ellen S.; Guo, Dongchuan; Prakash, Siddharth; Bensend, Tracy A.; Flynn, Kelly; Estrera, Anthony; Safi, Hazim; Liang, David; Hyland, James; Child, Anne; Arno, Gavin; Boileau, Catherine; Jondeau, Guillaume; Braverman, Alan; Moran, Rocio; Morisaki, Takayuki; Morisaki, Hiroko; Consortium, Montalcino Aortic; Pyeritz, Reed; Coselli, Joseph; LeMaire, Scott; Milewicz, Dianna M.

    2015-01-01

    Background ACTA2 mutations are the major cause of familial thoracic aortic aneurysms and dissections. We sought to characterize these aortic diseases in a large case series of individuals with ACTA2 mutations. Methods and Results Aortic disease, management, and outcome associated with the first aortic event (aortic dissection or aneurysm repair) were abstracted from the medical records of 277 individuals with 41 various ACTA2 mutations. Aortic events occurred in 48% of these individuals, with the vast majority presenting with thoracic aortic dissections (88%) associated with 25% mortality. Type A dissections were more common than type B dissections (54% versus 21%), but the median age of onset of type B dissections was significantly younger than type A dissections (27 years, IQR 18–41 versus 36 years, IQR 26–45). Only 12% of aortic events were repair of ascending aortic aneurysms, which variably involved the aortic root, ascending aorta and aortic arch. Overall cumulative risk of an aortic event at age 85 years was 0.76 (95% CI 0.64, 0.86). After adjustment for intra-familial correlation, gender and race, mutations disrupting p.R179 and p.R258 were associated with significantly increased risk for aortic events, whereas p.R185Q and p.R118Q mutations showed significantly lower risk of aortic events compared to other mutations. Conclusions ACTA2 mutations are associated with high risk of presentation with an acute aortic dissection. The lifetime risk for an aortic event is only 76%, suggesting that additional environmental or genetic factors play a role in expression of aortic disease in individuals with ACTA2 mutations. PMID:25759435

  1. Ensino de Astronomia no Ensino Médio

    NASA Astrophysics Data System (ADS)

    Albrecht, E.; Voelzke, M. R.

    2008-09-01

    O presente trabalho de intervenção foi realizado junto a Escola Estadual Colônia dos Pescadores na cidade de Caraguatatuba, com três turmas do terceiro ano do Ensino Médio, envolvendo 119 alunos, 40 na turma A, 40 na turma B e 39 na turma C. A fase inicial foi composta de um questionário de vinte questões dissertativas e objetivas para diagnosticar nos educandos os conceitos prévios sobre Astronomia e, partindo destes realizar uma interferência nas classes envolvidas utilizando metodologias diferentes sendo elas: a tradicional, onde o professor é um repassador de informações, fazendo uso exclusivo de lousa e giz; a segunda também de forma tradicional, porém com auxílio de multimídia para desenvolvimento das aulas e a terceira sob forma de seminários, elaborados e apresentados pelos educandos, no qual o educador faz apenas as intervenções necessárias. Ao final do trabalho as mesmas turmas da fase inicial orientadas pelo mesmo professor responderam novamente ao questionário proposto para diagnosticar dentre as três metodologias utilizadas qual apresentou melhores resultados, sendo os iniciais comparados com os finais. Quando questionados a respeito do significado de Astronomia observou-se inicialmente que os acertos na turma A foram de 100%,turma B: 64%, turma C: 84%, após a intervenção os acertos foram: 100%, 97% e 85% respectivamente, demonstrando claramente uma absorção de conhecimentos. Quando interrogados sobre quantos planetas você acha que existem em nosso Sistema Solar? os acertos foram: turma A: 39%, turma B: 48% e turma C: 46%, após o desenvolvimento do trabalho os acertos foram 94%, 97% e 90% respectivamente.Dentro das respostas obtidas observa-se que a metodologia tradicional com o auxílio de multimeios, aplicada na turma B, demonstrou melhores resultados, foi a mais significativa.

  2. On Ensino de Astronomia: Desafios para Implantação

    NASA Astrophysics Data System (ADS)

    Faria, R. Z.; Voelzke, M. R.

    2008-09-01

    Em 2002 o ensino de Astronomia foi proposto como um dos temas estruturadores pelos Parâmetros Curriculares Nacionais e sugerido como facilitador para que o aluno compreendesse a Física como construção humana e parte do seu mundo vivencial, mas raramente seus conceitos foram ensinados. A presente pesquisa discute dois aspectos relacionados à abordagem de Astronomia. O primeiro aspecto é se ela está sendo abordada pelos professores do Ensino Médio e o segundo, aborda a maneira como ela está sendo ensinada. Optou-se pela aplicação de um questionário a partir do 2° semestre de 2006 e durante o ano de 2007 com professores que ministram a disciplina de Física, os quais trabalham em escolas estaduais em Rio Grande da Serra, Ribeirão Pires e Mauá no estado São Paulo. Dos 66,2% dos professores que responderam ao questionário nos municípios de Rio Grande da Serra, Ribeirão Pires e Mauá, 57,4% não aplicaram nenhum tópico de astronomia, 70,2% não utilizaram laboratório, 89,4% não utilizaram qualquer tipo de programa computacional, 83,0% nunca fizeram visitas com alunos a museus e planetários e 38,3% não indicaram qualquer tipo de livro ou revista referente à astronomia aos seus alunos. Mesmo considerando a Astronomia um conteúdo potencialmente significativo, esta não fez parte dos planejamentos escolares. Portanto são necessárias propostas que visem estratégias para a educação continuada dos professores como, por exemplo, cursos específicos sobre o ensino em Astronomia.

  3. Cerebral arteriopathy associated with Arg179His ACTA2 mutation

    PubMed Central

    Amans, Matthew R; Stout, Charles; Fox, Christine; Narvid, Jared; Hetts, Steven W; Cooke, Daniel L; Higashida, Randall T; Dowd, Christopher F; McSwain, Hugh; Halbach, Van V

    2013-01-01

    ACTA2 mutations have recently been shown to cause a multisystem smooth muscle dysfunction syndrome that may result in pediatric stroke. We report a case of ACTA2 mutation in a 3-year-old girl presenting with acute ischemic stroke and provide high resolution imaging of the cerebral arteries demonstrating novel findings of multiple tiny aneurysms (particularly in the posterior circulation), as well as the more characteristic imaging phenotype of straightened and narrowed proximal intracranial vessels, dilated cervical vessels and occlusion of the M1 MCA segment without lenticulostriate collateral formation. This newly identified disease should be added to the differential diagnosis of pediatric stroke and cerebral vasculopathy. Neuroradiologists, interventionalists, surgeons and neurologists should become familiar with this rare disease and its clinical sequelae. PMID:24293535

  4. Cerebral arteriopathy associated with Arg179His ACTA2 mutation.

    PubMed

    Amans, Matthew R; Stout, Charles; Fox, Christine; Narvid, Jared; Hetts, Steven W; Cooke, Daniel L; Higashida, Randall T; Dowd, Christopher F; McSwain, Hugh; Halbach, Van V

    2013-01-01

    ACTA2 mutations have recently been shown to cause a multisystem smooth muscle dysfunction syndrome that may result in pediatric stroke. We report a case of ACTA2 mutation in a 3-year-old girl presenting with acute ischemic stroke and provide high resolution imaging of the cerebral arteries demonstrating novel findings of multiple tiny aneurysms (particularly in the posterior circulation), as well as the more characteristic imaging phenotype of straightened and narrowed proximal intracranial vessels, dilated cervical vessels and occlusion of the M1 MCA segment without lenticulostriate collateral formation. This newly identified disease should be added to the differential diagnosis of pediatric stroke and cerebral vasculopathy. Neuroradiologists, interventionalists, surgeons and neurologists should become familiar with this rare disease and its clinical sequelae. PMID:24293535

  5. Cerebral arteriopathy associated with Arg179His ACTA2 mutation.

    PubMed

    Amans, Matthew R; Stout, Charles; Fox, Christine; Narvid, Jared; Hetts, Steven W; Cooke, Daniel L; Higashida, Randall T; Dowd, Christopher F; McSwain, Hugh; Halbach, Van V

    2014-11-01

    ACTA2 mutations have recently been shown to cause a multisystem smooth muscle dysfunction syndrome that may result in pediatric stroke. We report a case of ACTA2 mutation in a 3-year-old girl presenting with acute ischemic stroke and provide high resolution imaging of the cerebral arteries demonstrating novel findings of multiple tiny aneurysms (particularly in the posterior circulation), as well as the more characteristic imaging phenotype of straightened and narrowed proximal intracranial vessels, dilated cervical vessels and occlusion of the M1 MCA segment without lenticulostriate collateral formation. This newly identified disease should be added to the differential diagnosis of pediatric stroke and cerebral vasculopathy. Neuroradiologists, interventionalists, surgeons and neurologists should become familiar with this rare disease and its clinical sequelae. PMID:24353327

  6. Situação da Mulher na Astronomia Brasileira

    NASA Astrophysics Data System (ADS)

    Silva, Adriana V. R.

    2007-07-01

    O conteúdo desse texto surgiu de uma apresentação de mesmo título que fiz na XXXI Reunião Anual da Sociedade Astronômica Brasileira (SAB) em 2005. Esse tema foi inspirado originalmente pela minha participação no "2nd UIPAP International Conference on Women in Physics" realizado entre 23 e 25 de maio de 2005 no Rio de Janeiro. Essa é uma conferência internacional que acontece de três em três anos, sendo que a primeira ocorreu em 2002 na cidade de Paris, França. Participei dessa conferência como membro da delegação da Sociedade Brasileira de Física e um dos trabalhos que apresentei versava sobre a situação das mulheres na Astronomia brasileira, cujos resultados principais discorro a seguir. A situação das astrônomas, baseada nos dados dos sócios da SAB coletados no final de 2004, é comparada com a das físicas brasileiras e também com as nossas colegas americanas. Os dados identificam ainda uma maior evasão da carreira por parte das mulheres do que os homens. Alguns dos possíveis motivos da evasão são discutidos, como o desejo de constituir família e/ou isolamento. Resultados um tanto preocupantes com relação à distribuição de bolsas de produtividade do CNPq também são apresentados. As principais discussões e estratégias recomendadas nesse congresso são mencionadas de forma resumida ao final.

  7. Langkocyclines: novel angucycline antibiotics from Streptomyces sp. Acta 3034(*).

    PubMed

    Kalyon, Bahar; Tan, Geok-Yuan A; Pinto, John M; Foo, Cheau-Yee; Wiese, Jutta; Imhoff, Johannes F; Süssmuth, Roderich D; Sabaratnam, Vikineswary; Fiedler, Hans-Peter

    2013-10-01

    Langkocyclines A1-A3 and B1 and B2, five new angucycline antibiotics produced by Streptomyces sp. Acta 3034, were detected in the course of our HPLC-diode array screening. The producing strain was isolated from the rhizospheric soil of a Clitorea sp. collected from Burau Bay, Langkawi, Malaysia, and was characterized by morphological, physiological and chemotaxonomic features in addition to 16S ribosomal RNA gene sequence information. Strain Acta 3034 is closely related to Streptomyces psammoticus NBRC 13971(T) and Streptomyces lanatus NBRC 12787(T). Langkocyclines consist of an angular tetracyclic benz[a]anthracene skeleton and hydrolyzable O-glycosidic sugar moieties. The yellow-colored A-type langkocyclines differ in their aglycon from the blue-lilac-colored B-type langkocyclines. The A-type langkocycline aglycon is identical to that of aquayamycin and urdamycin A. The chemical structures of the langkocyclines were elucidated by HR-MS, 1D and 2D NMR experiments. They are biologically active against Gram-positive bacteria and exhibit a moderate antiproliferative activity against various human tumor cell lines. PMID:23820614

  8. Ernesto Vasconcellos' Astronomia Photographica: the earliest popular book on astronomical photography?

    NASA Astrophysics Data System (ADS)

    Bonifácio, Vitor; Malaquias, Isabel; Fernandes, João

    2008-07-01

    Portugal, albeit with its own cultural distinctiveness, was not immune to the ideologies permeating nineteenth-century European society, in particular those concerning the social advantages of science and science popularisation. The country's high illiteracy rate hampered but did not prevent several popularisation efforts, which were usually led by professors and armed forces officers. In 1886 Astronomia Photographica (Astronomical Photography), a book popularising astrophotography, was published in Lisbon as part of a collection entitled People and Schools Library. The book seems an odd editorial choice given that, at the time, Portugal's major astronomical institutions pursued astrometric research and there was a virtual absence in the country of amateur astronomers. International astronomical developments, the author's interest in the scientific applications of photography and even the editorial timing are likely explanations for the publication of Astronomia Photographica, but we believe a definitive answer is still not available. The style of Astronomia Photographica is historical and informative, without being technical; clearly it is not a ‘hands-on guide’. The contents of the book show that the author, Ernesto Júlio de Carvalho e Vasconcellos, a naval officer, contacted several experts and was aware of the latest developments in astronomical photography. What makes this a unique book is its content, and its inclusion in a popularisation collection with an exceptionally high circulation at such an early time.

  9. Smooth Muscle α Actin (Acta2) and Myofibroblast Function during Hepatic Wound Healing

    PubMed Central

    Rockey, Don C.; Weymouth, Nate; Shi, Zengdun

    2013-01-01

    Smooth muscle α actin (Acta2) expression is largely restricted to smooth muscle cells, pericytes and specialized fibroblasts, known as myofibroblasts. Liver injury, associated with cirrhosis, induces transformation of resident hepatic stellate cells into liver specific myofibroblasts, also known as activated cells. Here, we have used in vitro and in vivo wound healing models to explore the functional role of Acta2 in this transformation. Acta2 was abundant in activated cells isolated from injured livers but was undetectable in quiescent cells isolated from normal livers. Both cellular motility and contraction were dramatically increased in injured liver cells, paralleled by an increase in Acta2 expression, when compared with quiescent cells. Inhibition of Acta2 using several different techniques had no effect on cytoplasmic actin isoform expression, but led to reduced cellular motility and contraction. Additionally, Acta2 knockdown was associated with a significant reduction in Erk1/2 phosphorylation compared to control cells. The data indicate that Acta2 is important specifically in myofibroblast cell motility and contraction and raise the possibility that the Acta2 cytoskeleton, beyond its structural importance in the cell, could be important in regulating signaling processes during wound healing in vivo. PMID:24204762

  10. VIII Olimpíada Brasileira de Astronomia e Astronáutica

    NASA Astrophysics Data System (ADS)

    Garcia Canalle, João Batista; Villas da Rocha, Jaime Fernando; Wuensche de Souza, Carlos Alexandre; Pereira Ortiz, Roberto; Aguilera, Nuricel Villalonga; Padilha, Maria De Fátima Catta Preta; Pessoa Filho, José Bezerra; Soares Rodrigues, Ivette Maria

    2007-07-01

    Neste trabalho apresentamos as motivações pelas quais organizamos, em conjunto, pela primeira vez, a Olimpíada Brasileira de Astronomia incluindo a Astronáutica, em colaboração com a Agência Espacial Brasileira. Esta ampliação contribuiu para atrair ainda mais alunos, professores, escolas e patrocinadores para participarem desta Olimpíada. Em 2005 participaram da VIII Olimpíada Brasileira de Astronomia e Astronáutica (VIII OBA) 187.726 alunos distribuídos por 3.229 escolas, pertencentes a todos os estados brasileiros, incluindo o Distrito Federal. O crescimento em número de alunos participantes foi 52,4% maior do que em 2004. Em abril de 2005 organizamos, em Itapecerica da Serra, SP, um curso para os 50 alunos previamente selecionados e participantes da VII OBA e ao final selecionamos, dentre eles, uma equipe de 5 alunos, os quais representaram o Brasil na X Olimpíada Internacional de Astronomia, na China, em outubro de 2005. Ganhamos, pela primeira vez, uma medalha de ouro naquele evento. Em Agosto de 2005, organizamos a VIII Escola de Agosto para 50 alunos e respectivos professores, em Águas de Lindóia, SP, juntamente com a XXXI reunião anual da Sociedade Astronômica Brasileira (SAB). Em novembro de 2005 realizamos a I Jornada Espacial, em São José dos Campos, com 22 alunos e 22 professores selecionados dentre os participantes que melhores resultados obtiveram nas questões de Astronáutica da VIII OBA. Neste trabalho detalhamos os resultados da VIII OBA bem como as ações subseqüentes.

  11. Astronomia cultural e meio ambiente segundo uma abordagem holística

    NASA Astrophysics Data System (ADS)

    Jafelice, L. C.

    2003-08-01

    Neste trabalho ampliamos a discussão da abordagem holística para o ensino de astronomia que temos desenvolvido nos últimos anos, analisamos novos resultados e apresentamos exemplos práticos para interessados em experimentá-la. A constatação básica a orientar este enfoque é que cursos introdutórios em astronomia costumam ser excessiva e prematuramente técnicos, além de assumirem uma visão tradicional, muito estreita, do que seja educação científica, herdada da era cartesiana e positivista da ciência. Fundamentamos porque é importante que elementos de astronomia cultural ofereçam o mote e constituam o eixo norteador daqueles cursos e porque é urgente revermos a visão que temos da relação entre astronomia e meio ambiente. Um ponto central nesta abordagem é explorar formas de reativar e atualizar uma relação orgânica com o meio e excitar a consciência de nossa inevitável e profunda interdependência com ele em nível cósmico. Neste trabalho exemplificamos a possibilidade de concretização desta proposta em três diferentes situações: disciplinas de cursos de licenciatura em geografia e em física; escolas de nível fundamental; e, neste caso ainda a ser implementada, comunidades carentes. Estes casos envolvem públicos e espaços diferenciados para educação formal e não-formal. Dos casos já implementados, destacamos os resultados alcançados pelos alunos: enriquecimento cultural, aprendizagem significativa de conteúdos astronômicos tradicionais; mudanças de comportamento, incorporando contato diário com o céu; e freqüentes vivências de sentimentos empáticos que redirecionam a relação com a natureza e a consciência ecológica global. Além disto, para interessados em aplicar esta proposta, também socializamos procedimentos e cuidados para a implementação de ações alternativas consonantes com a mesma. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

  12. Acta Informatica Medica Is Indexed In Pubmed And Archived In Pubmed Central

    PubMed Central

    Masic, Izet

    2013-01-01

    Acta Informatica Medica journal has been accepted for archiving in PubMed Central from 2011 onward. The journal started in 1993 as the official journal of the Society for Medical Informatics of Bosnia and Herzegovina. During the last 3 years, Acta Informatica Medica has een included in almost all prestigious online databases, including PubMed, Scopus and EMBASE. The 20th volume of the journal is fully international, with papers from 18 countries. PMID:23572852

  13. On Ensino de Astronomia nas Cidades de Ribeirão Pires e Rio Grande da Serra

    NASA Astrophysics Data System (ADS)

    Faria, R. Z.; Voelzke, M. R.

    2007-08-01

    Apesar da astronomia ser um dos temas indicados pelos Parâmetros Curriculares Nacionais, observa-se que poucas mudanças ocorreram desde a implementação do mesmo em sala de aula. A presente pesquisa diz respeito sobre como os tópicos de astronomia estão sendo abordados pelos professores no ensino médio. Optou-se por aplicar um questionário com os professores que ministram a disciplina de física. Os mesmos trabalham em escolas estaduais situadas nas cidades de Ribeirão Pires e Rio Grande da Serra, ambas subordinadas a Diretoria de Ensino de Mauá, no Estado de São Paulo. O questionário foi aplicado durante o 2° semestre de 2006. Até o momento os resultados são preliminares. Dos 82,0% dos professores que responderam ao questionário no município de Rio Grande da Serra, 66,7% não aplicaram nenhum tópico de astronomia, 77,8% não utilizaram qualquer tipo de programa computacional, 66,7% não utilizaram laboratório, que 77,8% nunca levaram os alunos a museus e ou planetários e que 66,7% não indicaram qualquer tipo de revista ou livro sobre astronomia aos seus alunos. No município de Ribeirão Pires, 53,3% dos professores responderam ao questionário, destes 75,0% não aplicaram nenhum tópico de astronomia, 93,8% não utilizaram qualquer tipo de programa computacional, 75,0% não utilizaram laboratório, 81,3% nunca levaram os alunos a museus e ou planetário e 56,3% não indicaram qualquer tipo de revista ou livro sobre astronomia ao seus alunos. Apesar da maioria dos professores reconhecerem que o conteúdo de astronomia influi na formação do jovem, os mesmos não incluem o tema em seus planejamentos escolares.

  14. A Utilização da Astronomia como Tema Interdisciplinar e Aplicações de Objetos de Aprendizagem

    NASA Astrophysics Data System (ADS)

    da Silva, L. A.; Voelzke, M. R.

    2008-09-01

    Este trabalho visa analisar a possibilidade de relacionar conteúdos aplicados no ensino fundamental e médio de forma interdisciplinar por intermédio da astronomia, com a intervenção de objetos de aprendizagem que possam integrar as disciplinas e a utilização de recursos tecnológicos. Em uma pesquisa prévia com 20 professores de uma escola estadual situada na cidade de Guarulhos foi observado que apenas 25% dos professores utilizam algum recurso tecnológico para o desenvolvimento de conteúdos pertinentes à sua disciplina, tais como sites e softwares educativos, sendo que a maioria absoluta continua ensinando apenas com livros didáticos. A maior parte dos professores apresenta dificuldades em trabalhar sua disciplina de forma interdisciplinar, ou seja, 75% dos professores preferem aplicar os conteúdos seguindo uma hierarquia linear de tópicos, evitando a discussão de temas que de alguma forma estão relacionados. A astronomia pode vir à fascinar o ser humano e despertar sua curiosidade promovendo um maior interesse no aprendizado, podendo favorecer análises interdisciplinares de forma lógica e objetiva, desta forma colocar a astronomia como tema motivador interdisciplinar, pode ser relevante no que se refere ao distanciamento da fragmentação dos conteúdos. No Estado de São Paulo, a implantação da proposta curricular no ensino fundamental e médio mostra claramente a inserção da astronomia na maior parte das séries, principalmente na 6ª série em que todo o bimestre se fala de astronomia.

  15. Diferentes metodologias aplicadas ao ensino de astronomia no Ensino Médio

    NASA Astrophysics Data System (ADS)

    Albrecht, E.; Voelzke, M. R.

    2009-03-01

    O presente trabalho de intervenção foi realizado junto à Escola Estadual Colònia dos Pescadores na cidade de Caraguatatuba, com très turmas do terceiro ano do Ensino Médio, envolvendo 119 alunos com idades entre 16 e 19 anos. A fase inicial foi composta de um questionário de vinte questíes dissertativas e objetivas, aplicado pelo professor titular da sala, que era o mesmo nas très turmas, para diagnosticar nos educandos os conceitos prévios sobre Astronomia e, partindo destes realizar um trabalho de intervenção nas classes envolvidas utilizando, em cada uma, metodologias diferentes: (A) sob forma de seminários, elaborados e apresentados pelos educandos, no qual o educador faz apenas as intervençíes necessárias; (B) de forma tradicional, com auxílio de multimídias para desenvolvimento das aulas e a terceira (C) tradicional, fazendo uso exclusivo de lousa e giz. Ao final do trabalho os alunos responderam novamente o questionário inicial para diagnosticar dentre as très metodologias utilizadas qual apresentou melhores aplicaçíes, os resultados iniciais foram comparados com os finais. Quando questionados a respeito do significado de Astronomia observou-se inicialmente que os acertos na turma A foram de 100%, turma B: 64%, turma C: 84%, após a intervenção os acertos foram: 100%, 97% e 85% respectivamente, demonstrando que houve um avanço significativo na turma B, a turma A manteve seu índice e a turma C evoluiu, porém não tanto quanto a B. Quando interrogados sobre quantos planetas vocè acha que existem em nosso Sistema Solar? os acertos foram: turma A: 39%, turma B: 48% e turma C: 46%, após o desenvolvimento do trabalho os acertos foram 94%, 97% e 90% respectivamente. Dentro das respostas obtidas observa-se que a metodologia tradicional com o auxílio de multimeios, aplicada na turma B, demonstrou melhores resultados, sendo a mais significativa. Outra conclusão muito importante é que apesar de o tema Astronomia ser amplamente

  16. De Novo ACTA2 Mutation Causes a Novel Syndrome of Multisystemic Smooth Muscle Dysfunction

    PubMed Central

    Milewicz, Dianna M.; Østergaard, John R.; Ala-Kokko, Leena M.; Khan, Nadia; Grange, Dorothy K.; Mendoza-Londono, Roberto; Bradley, Timothy J.; Olney, Ann Haskins; Adès, Lesley; Maher, Joseph F.; Guo, Dongchuan; Buja, L. Maximilian; Kim, Dong; Hyland, James C.; Regalado, Ellen S.

    2011-01-01

    Smooth muscle cells (SMCs) contract to perform many physiological functions, including regulation of blood flow and pressure in arteries, contraction of the pupils, peristalsis of the gut and voiding of the bladder. SMC lineage in these organs is characterized by cellular expression of the SMC isoform of α-actin, encoded by the ACTA2 gene. We report here on a unique and de novo mutation in ACTA2, R179H, that causes a syndrome characterized by dysfunction of SMCs throughout the body, leading to aortic and cerebrovascular disease, fixed dilated pupils, hypotonic bladder, malrotation and hypoperistalsis of the gut and pulmonary hypertension. PMID:20734336

  17. Activities of the Sociedad Española de Astronomia during the International Year of Astronomy 2009

    NASA Astrophysics Data System (ADS)

    Montesinos, B.

    2011-11-01

    In this paper we summarize the activities carried out by the SpanishAstronomical Society during the International Year of Astronomy2009. The Society contributed with several key projects to the overallpool of actions coordinated from the National Node, trying -andachieving- to reach as many people as possible through thepublication and free distribution of the book "Astronomia madein Spain" and a collaboration with the digital edition of El Paisduring the entire year 2009. Other activities and by-products are alsodescribed.

  18. Review of the Journal Acta Informatica Medica During Eight Year Period: 2008-2015

    PubMed Central

    Masic, Izet; Begic, Edin; Zunic, Lejla

    2016-01-01

    Introduction: Acta Informatica Medica is official journal of the Academy for Medical Sciences of Bosnia and Herzegovina (from 2014 Acta Inform Med is published bimonthly). Aim: To evaluate journal “Acta Informatica Medica” in 2015 and compare findings to previous years. Material and methods: The study has retrospective and descriptive character, and included the period 2008-2015 (included 36 issues of journal). Results: A total of 83 (average 13,8 articles per journal) articles were published in Acta Informatica Medica during 2015. Analyzing the type of articles, original articles are present in majority during 2015 (68,6%) (by analyzing last eight years, 310 (67,3%) were original). During 2015, 27,7% of articles were related to the applied of Health informatics in field of clinical medicine, 63,8% preclinical medicine and 8,5% to public health. Collaboration rate in 2015 was 0,84. Most often the time required for decision on acceptance of article in 2015 is between 50 and 60 days. Articles came from 16 countries. According to scimagojr.com for 2014, Acta Informatica Medica has SCImago Journal Rank 0,166, while Cites / Doc. (2 years) parameter (widely used as impact index) is 0,70. According to GoogleScholar, h5 index is 11 and h5 median is 19. We analyzed the Acta Informatica Medica by “Publish or Perish” software - H index was 14, g index was 19 and e-index was 10.39. Conclusion: Year after year the highest number of original articles are published. Although the period of revision of articles is acceptable, the period up to two months is certainly not long, the goal is to reduce this period. Although the magazine in mentioned field found its place, although it is indexed in numerous bases, including: PubMed, PubMed Central, SCOPUS, EMBASE, EBSCO, etc. The main goal for next year is that the magazine becomes part of the Web of Science. Imperative is further internationalization of the magazine. PMID:27147796

  19. Cosmoeducação: uma proposta para o ensino de astronomia

    NASA Astrophysics Data System (ADS)

    Medeiros, L. A. L.; Jafelice, L. C.

    2003-08-01

    Entende-se por cosmoeducação o desenvolvimento vivencial da unidade homem-cosmo. Este conceito é norteado pela psicologia transpessoal, que estuda o ser humano em sua totalidade, onde suas relações ecológicas e cósmicas são de grande importância. Constata-se uma necessidade latente no ser humano moderno em resgatar uma relação holística com o Universo. Neste trabalho exploramos meios de cultivar a consciência de que o ser humano constitui parte integrante do cosmo e se relaciona com este com o objetivo de promover em si uma percepção ambiental mais ampla. Nossa hipótese de trabalho inicial foi que o ensino de conteúdos básicos em astronomia realizado através de uma abordagem holística, que incorpore práticas vivenciais correlacionadas àqueles conteúdos, pode despertar no indivíduo sua identidade cósmica. O método que utilizamos é o fenomenológico e o universo desta pesquisa é um grupo de estudantes da disciplina de Astronomia (Curso de Licenciatura em Geografia/UFRN), onde realizamos observação participante, entrevistas, depoimentos e as práticas vivenciais mencionadas. Neste caso estamos desenvolvendo e adaptando exercícios de algumas técnicas terapêuticas de psicologia transpessoal, que um de nós (LALM) tem aplicado no contexto clínico, para trabalhar aspectos cognitivos envolvidos naquele processo de conscientização cósmica. Resultados parciais claramente referendam a hipótese inicial. Um resultado a destacar é fruto de uma dinâmica de representação corporal interiorizada do eclipse lunar, envolvendo um pequeno grupo daqueles estudantes, na qual conteúdos míticos afloraram de maneira espontânea e contundente para todos, sugerindo ressonância, ou pelo menos isomorfismo, entre o macro e o microcosmo. Este e outros resultados são discutidos em detalhe neste trabalho. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP).

  20. Tendências de teses e dissertações sobre ensino de astronomia no Brasil

    NASA Astrophysics Data System (ADS)

    Bretones, P. S.; Megid Neto, J.

    2003-08-01

    Neste trabalho são apresentados os resultados de uma pesquisa do tipo estado da arte sobre teses e dissertações defendidas no Brasil e relativas ao ensino de Astronomia. Teve por objetivo identificar essa produção e conhecer as principais tendências da pesquisa nesse campo. O procedimento inicial consistiu de um levantamento bibliográfico junto ao Centro de Documentação em Ensino de Ciências (CEDOC) da Faculdade de Educação da UNICAMP e ao Banco de Teses da CAPES disponível na Internet. Foram localizadas 13 dissertações de mestrado e 3 teses de doutorado, as quais foram estudadas em função dos seguintes aspectos: instituição, ano de defesa, nível escolar abrangido no estudo, foco temático do estudo e gênero de trabalho acadêmico. Deste conjunto de pesquisas, 13 (81,3%) delas foram defendidas a partir da segunda metade dos anos 90, indicando uma preocupação mais recente com temas relativos ao ensino de Astronomia no conjunto da produção acadêmica em programas de pós-graduação no Brasil. Verificou-se que 43,7% dos trabalhos foram produzidas na USP e 18,8% na UNICAMP. Quanto ao nível escolar abrangido nos estudos, predominaram os estudos direcionados ao Ensino Fundamental de 5a a 8a séries (62,5%). No que diz respeito ao foco temático das pesquisas, as principais tendências voltaram-se: 56,3% para Conteúdo e Método; 43,8% para Concepções do Professor; 37,5% para Currículo e Programas; 37,5% para Recursos Didáticos. Quanto ao gênero de trabalho acadêmico, verificou-se que 43,8% são de Pesquisa Experimental e 31,3% de Pesquisa de Análise de Conteúdo. Estudos de revisão bibliográfica como este visam colaborar com a divulgação ampla da produção acadêmica em determinada área, traçando algumas de suas tendências. Ao mesmo tempo possibilita, a partir de investigações decorrentes, apontar as suas contribuições para o ensino e sinalizar com necessidades a serem supridas por futuras pesquisas.

  1. On Ensino da Astronomia no Ensino Médio sob Diferentes Abordagens Metodológicas

    NASA Astrophysics Data System (ADS)

    Voelzke, Marcos Rincon; Albrecht, Evonir

    2011-12-01

    O presente trabalho, sobre a intervenção de metodologias de ensino, foi desenvolvido na Escola Estadual Colônia dos Pescadores, na cidade de Caraguatatuba - SP, em três turmas do terceiro ano do Ensino Médio, perfazendo um total de 119 educandos, entre 16 e 19 anos. Antes de iniciar-se a intervenção, um questionário de vinte perguntas objetivas e dissertativas foi desenvolvido, aplicado pelo professor da classe, que ministrou as aulas correspondentes. Este questionário foi o mesmo em todas as três classes com o objetivo de diagnosticar o conhecimento prévio dos alunos sobre Astronomia. Começando a intervenção nas turmas, o professor envolvido usou três diferentes metodologias de ensino: (A) em forma de seminários, elaborados e apresentados pelos alunos, nos quais o professor fazia apenas as intervenções necessárias, (B) na forma tradicional, com a ajuda de multimídia para o desenvolvimento das aulas e a terceira (C) a tradicional, fazendo uso exclusivo de lousa e giz. No final do trabalho os alunos responderam o mesmo questionário novamente, de modo que os três métodos utilizados puderam ser comparados. Os resultados apresentados após a intervenção foram melhores que os resultados iniciais indicando a ocorrência de uma aprendizagem significativa. Quando os estudantes foram inicialmente questionados sobre quantos planetas existem no nosso sistema solar, a classe A obteve 39% de respostas certas, a classe B 48% e a classe C 46%, mas após o desenvolvimento das atividades, as classes obtiveram respectivamente 94%, 97 % e 90% de aproveitamento. No término do bimestre, foi sugerido aos educandos que elaborassem uma história em quadrinhos, a qual serviu para averiguar se os conceitos inicialmente observados foram alterados e se novos foram agregados. A análise das histórias foi dividida em três partes: Criatividade; Temas abordados; Emprego correto dos conceitos estudados. Ao final quatorze histórias foram confeccionadas. O aprendizado

  2. Astronomia para/com crianças carentes em Limeira

    NASA Astrophysics Data System (ADS)

    Bretones, P. S.; Oliveira, V. C.

    2003-08-01

    Em 2001, o Instituto Superior de Ciências Aplicadas (ISCA Faculdades de Limeira) iniciou um projeto pelo qual o Observatório do Morro Azul empreendeu uma parceria com o Centro de Promoção Social Municipal (CEPROSOM), instituição mantida pela Prefeitura Municipal de Limeira para atender crianças e adolescentes carentes. O CEPROSOM contava com dois projetos: Projeto Centro de Convivência Infantil (CCI) e Programa Criança e Adolescente (PCA), que atendiam crianças e adolescentes em Centros Comunitários de diversas áreas da cidade. Esses projetos têm como prioridades estabelecer atividades prazerosas para as crianças no sentido de retirá-las das ruas. Assim sendo, as crianças passaram a ter mais um tipo de atividade - as visitas ao observatório. Este painel descreve as várias fases do projeto, que envolveu: reuniões de planejamento, curso de Astronomia para as orientadoras dos CCIs e PCAs, atividades relacionadas a visitas das crianças ao Observatório, proposta de construção de gnômons e relógios de Sol nos diversos Centros Comunitários de Limeira e divulgação do projeto na imprensa. O painel inclui discussões sobre a aprendizagem de crianças carentes, relatos que mostram a postura das orientadoras sobre a pertinência do ensino de Astronomia, relatos do monitor que fez o atendimento no Observatório e o que o número de crianças atendidas representou para as atividades da instituição desde o início de suas atividades e, em particular, em 2001. Os resultados são baseados na análise de relatos das orientadoras e do monitor do Observatório, registros de visitas e matérias da imprensa local. Conclui com uma avaliação do que tal projeto representou para as Instituições participantes. Para o Observatório, em particular, foi feita uma análise com relação às outras modalidades de atendimentos que envolvem alunos de escolas e público em geral. Também é abordada a questão do compromisso social do Observatório na educação do

  3. Citation analysis of Acta Dermatovenerologica Alpina, Pannonica et Adriatica: 1992-2011.

    PubMed

    Ostrbenk, Anja; Skamperle, Mateja; Poljak, Mario

    2012-09-01

    Acta Dermatovenerologica Alpina, Pannonica et Adriatica is small regional professional journal that started publishing in 1992. Despite the journal's relatively narrow readership, it has significantly improved its quality and global profile during the last 20 years, as shown in this citation analysis update. Since 1992, 654 bibliographical items have been published. Among these, 545 (83.4%) were considered WoS citable items and 109 (16.6%) WoS noncitable items. Since 2008, 90% of all published items have been considered WoS citable items and received an average of 1.9 citations per item. The predicted Acta Dermatovenerol APA impact factor calculated using data from a Cited Reference search of Thomson Scientific's Web of Science has shown steep and continuous increase since 2006, when the journal acquired full indexing status in Index Medicus/Medline, and has been above 0.5 since 2008. PMID:23267871

  4. Novel MYH11 and ACTA2 mutations reveal a role for enhanced TGFβ signaling in FTAAD

    PubMed Central

    Renard, Marjolijn; Callewaert, Bert; Baetens, Machteld; Campens, Laurence; MacDermot, Kay; Fryns, Jean-Pierre; Bonduelle, Maryse; Dietz, Hal; Gaspar, Isabel Mendes; Cavaco, Diogo; Stattin, Eva-Lena; Schrander-Stumpel, Constance; Coucke, Paul; Loeys, Bart; De Paepe, Anne; De Backer, Julie

    2011-01-01

    Background Thoracic aortic aneurysm / dissection (TAAD) is a common phenotype that may occur as an isolated manifestation or within the constellation of a defined syndrome. In contrast to syndromic TAAD, the elucidation of the genetic basis of isolated TAAD has only recently started. To date, defects have been found in genes encoding extracellular matrix proteins (fibrillin-1, FBN1; collagen type III alpha 1, COL3A1), proteins involved in transforming growth factor beta (TGFβ) signaling (TGFβ receptor 1 and 2, TGFBR1/2; and SMAD3) or proteins that build up the contractile apparatus of aortic smooth muscle cells (myosin heavy chain 11, MYH11; smooth muscle actin alpha 2, ACTA2; and MYLK). Methods and results In 110 non-syndromic TAAD patients that previously tested negative for FBN1 or TGFBR1/2 mutations, we identified 7 ACTA2 mutations in a cohort of 43 familial TAAD patients, including 2 premature truncating mutations. Sequencing of MYH11 revealed an in frame splice-site alteration in one out of two probands with TAA(D) associated with PDA but none in the series of 22 probands from the cohort of 110 patients with non-syndromic TAAD. Interestingly, immunohistochemical staining of aortic biopsies of a patient and a family member with MYH11 and patients with ACTA2 missense mutations showed upregulation of the TGFβ signaling pathway. Conclusions MYH11 mutations are rare and typically identified in patients with TAAD associated with PDA. ACTA2 mutations were identified in 16% of a cohort presenting familial TAAD. Different molecular defects in TAAD may account for a different pathogenic mechanism of enhanced TGFβ signaling. PMID:21937134

  5. OV-Wav: um novo pacote para análise multiescalar em astronomia

    NASA Astrophysics Data System (ADS)

    Pereira, D. N. E.; Rabaça, C. R.

    2003-08-01

    Wavelets e outras formas de análise multiescalar têm sido amplamente empregadas em diversas áreas do conhecimento, sendo reconhecidamente superiores a técnicas mais tradicionais, como as análises de Fourier e de Gabor, em certas aplicações. Embora a teoria dos wavelets tenha começado a ser elaborada há quase trinta anos, seu impacto no estudo de imagens astronômicas tem sido pequeno até bem recentemente. Apresentamos um conjunto de programas desenvolvidos ao longo dos últimos três anos no Observatório do Valongo/UFRJ que possibilitam aplicar essa poderosa ferramenta a problemas comuns em astronomia, como a remoção de ruído, a detecção hierárquica de fontes e a modelagem de objetos com perfis de brilho arbitrários em condições não ideais. Este pacote, desenvolvido para execução em plataforma IDL, teve sua primeira versão concluída recentemente e está sendo disponibilizado à comunidade científica de forma aberta. Mostramos também resultados de testes controlados ao quais submetemos os programas, com a sua aplicação a imagens artificiais, com resultados satisfatórios. Algumas aplicações astrofísicas foram estudadas com o uso do pacote, em caráter experimental, incluindo a análise da componente de luz difusa em grupos compactos de galáxias de Hickson e o estudo de subestruturas de nebulosas planetárias no espaço multiescalar.

  6. Insertion of Astronomy as a High School Subject. (Spanish Title: Inserción de Astronomia Como Materia del Ciclo Secundario.) Inserção da Astronomia Como Disciplina Curricular do Ensino Médio

    NASA Astrophysics Data System (ADS)

    Dias, Claudio André C. M.; Santa Rita, Josué R.

    2008-12-01

    Astronomy is considered among the first sciences that man dominated, however, the basic skills for the construction of knowledge, relatively to the contents "Earth and the Universe" are not being developed properly for the majority of students concluding the high school level. The students are concluding this teaching cycle without proper knowledge of several subjects in the area of Astronomy, which are mandatory in the national Curricular National Parameters (PCN). Because of this discrepancy, this work stresses the need of the incorporation of a specific subject of Astronomy in the high school, in order to reduce the gap between what is taught and which should be taught. La Astronomía es considerada una de las primeras ciencias que el hombre dominó. Sin embargo, las habilidades básicas para la construcción del conocimento, relativo al eje temático "Tierra y Universo", no vienen siendo trabajadas adecuadamente con la mayoría de los alumnos que concluyen el ciclo escolar medio. Los alumnos están concluyendo este nivel de enseñanza sin conocimentos de varios temas en el área de Astronomía, que son obligatorios según los Parámetros Curriculares Nacionales (PCN). En virtud de esta discrepancia, este trabajo enfatiza la necesidad de incorporar una disciplina específica de Astronomía em el ciclo medio, em pro de la reducción de las distorsiones entre lo que es enseñado y lo que se debe enseñar. A Astronomia é considerada uma das primeiras ciências que o homem dominou, porém as competências básicas para a construção do conhecimento, relativo ao eixo temático "Terra e Universo", não vêm sendo trabalhadas a contento com a maioria dos alunos que concluem o ensino médio. Os alunos estão concluindo este nível de ensino sem conhecimento de vários temas na área de Astronomia, que são obrigatórios nos Parâmetros Curriculares Nacionais (PCN). Em virtude desta discrepância, este trabalho vem evidenciar a necessidade da incorporação de uma

  7. Ensino e divulgação de astronomia no Planetário de Campinas

    NASA Astrophysics Data System (ADS)

    Faria, R. P.

    2003-08-01

    Projeto desenvolvido em 1981 por professores da Unicamp, sob a coordenação do Prof. Dr. Carlos Alfredo Argüello propunha a instalação de um Planetário em Campinas. Convênio firmado em 1982 entre a Unicamp, a Prefeitura de Campinas, a Funcamp e a Academia de Ciências do Estado de São Paulo, possibilitou a aquisição de um planetário Zeiss ZKP2, através do MEC, e em 28 de outubro de 1987 foi inaugurado o Planetário de Campinas. Desde então várias atividades de ensino e divulgação da Astronomia foram desenvolvidas regularmente. A verificação dos registros das atividades realizadas mostra um alto índice de atendimento, considerada a capacidade das instalações (sala de projeção para 60 pessoas, auditório com 45 poltronas e hall de exposições). As atividades dirigidas ao público, estudantes e professores, atenderam cerca de 400.000 participantes nos quase 16 anos de sua existência. Além de sessões públicas e escolares, com duração de 1 hora, são oferecidas às escolas vários outros tipos de atividades, com duração de 2,5 horas. Abordam diversos temas e são dirigidas a diferentes níveis de escolaridade. Cursos para o público e para professores, palestras, exposições e eventos especiais completam o quadro de atividades regulares. Mesmo enfrentando quase sempre dificuldades financeiras e administrativas verifica-se que o Planetário de Campinas realizou um trabalho quantitativamente e qualitativamente satisfatório, prestando bom serviços à comunidade de Campinas e de outras cidades de São Paulo e outros Estados. Isso é também atestado pela grande procura de reservas para suas atividades.

  8. Um enfoque antropológico para o ensino de astronomia no nível médio

    NASA Astrophysics Data System (ADS)

    Costa, G. B.; Jafelice, L. C.

    2003-08-01

    Há uma enorme carência de materiais didático-pedagógicos em astronomia para professores do ensino médio, sobretudo materiais que explorem também aspectos humanísticos. A origem do Universo é um bom exemplo desta constatação central. Embora tal origem teve explicações culturais diversas, os professores não têm informações sobre isso e muito menos material que trabalhe diferentes visões de mundo e treinamento que os capacite a abordá-las devidamente. Conseqüentemente o ensino de astronomia costuma ser tecnicista e dissociado do aspecto humano que alimenta o grande interesse e curiosidade que esses temas despertam. Aqui apresentamos propostas visando contribuir para reverter esse quadro e trabalhamos distintas visões de Universo: espontâneas, autóctones e científicas. Desenvolvemos práticas, materiais instrucionais e textos para viabilizar a adoção de um enfoque antropológico para o ensino de astronomia no nível médio, no qual as culturas humanística e científica sejam integradas de uma maneira contextualizada e eficaz para aquele ensino. Estas propostas foram aplicadas em um curso de treinamento para professores da rede pública de diferentes disciplinas. A receptividade dos professores à abordagem proposta e os resultados alcançados foram muito estimulantes. Destes, destacamos: produção de roteiros de atividades; desenvolvimento de práticas didático-pedagógicas específicas (e.g., encenação de mitos; dança primordial guarani; "criação" de constelações e interpretações pluriculturais; etc.); e sugestões concretas para a efetiva realização de um ensino interdisciplinar contextualizado, onde questões cosmogônicas servem de mote para iniciar tal ensino. Discutimos estes resultados e como o enfoque adotado pode instrumentalizar os professores para leituras de mundo que incluem naturalmente aspectos culturais, sociais e históricos associados aos temas estudados. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

  9. Myopathy-inducing mutation H40Y in ACTA1 hampers actin filament structure and function.

    PubMed

    Chan, Chun; Fan, Jun; Messer, Andrew E; Marston, Steve B; Iwamoto, Hiroyuki; Ochala, Julien

    2016-08-01

    In humans, more than 200 missense mutations have been identified in the ACTA1 gene. The exact molecular mechanisms by which, these particular mutations become toxic and lead to muscle weakness and myopathies remain obscure. To address this, here, we performed a molecular dynamics simulation, and we used a broad range of biophysical assays to determine how the lethal and myopathy-related H40Y amino acid substitution in actin affects the structure, stability, and function of this protein. Interestingly, our results showed that H40Y severely disrupts the DNase I-binding-loop structure and actin filaments. In addition, we observed that normal and mutant actin monomers are likely to form distinctive homopolymers, with mutant filaments being very stiff, and not supporting proper myosin binding. These phenomena underlie the toxicity of H40Y and may be considered as important triggering factors for the contractile dysfunction, muscle weakness and disease phenotype seen in patients. PMID:27112274

  10. Langkolide, a 32-membered macrolactone antibiotic produced by Streptomyces sp. Acta 3062.

    PubMed

    Helaly, Soleiman E; Kulik, Andreas; Zinecker, Heidi; Ramachandaran, Kamalanathan; Tan, Geok Yuan Annie; Imhoff, Johannes F; Süssmuth, Roderich D; Fiedler, Hans-Peter; Sabaratnam, Vikineswary

    2012-06-22

    A new 32-membered macrolactone antibiotic, named langkolide, was isolated from the mycelium of Streptomyces sp. Acta 3062. The langkolide structure was determined by HR-MS and 1D and 2D NMR as a 32-membered macrolactone connected from an overhanging polyketide tail to a naphthoquinone unit mediated by two carbohydrate moieties. The producing strain was isolated from a rhizosphere soil of Clitorea sp. collected at Burau Bay, Langkawi, Malaysia, and was characterized by its morphological and chemotaxonomic features in addition to its 16S rRNA gene sequence. It was identified as a member of the Streptomyces galbus clade. Langkolide exhibited various bioactivities including antimicrobial and antiproliferative activities. Furthermore, langkolide inhibited human recombinant phosphodiesterase 4 with an IC(50) value of 0.48 μM. PMID:22642587

  11. Crystallization reports are the backbone of Acta Cryst. F, but do they have any spine?

    PubMed Central

    Newman, Janet; Burton, Denis R.; Caria, Sofia; Desbois, Sebastien; Gee, Christine L.; Fazio, Vincent J.; Kvansakul, Marc; Marshall, Bevan; Mills, Grant; Richter, Viviane; Seabrook, Shane A.; Wu, Mingbo; Peat, Thomas S.

    2013-01-01

    Crystallization of macromolecules is famously difficult. By knowing what has worked for others, researchers can ease the process, both in the case where the protein has already been crystallized and in the situation where more general guidelines are needed. The 264 crystallization communications published in Acta Crystallographica Section F in 2012 have been reviewed, and from this analysis some information about trends in crystallization has been gleaned. More importantly, it was found that there are several ways in which the utility of these communications could be increased: to make each individual paper a more complete crystallization record; and to provide a means for taking a snapshot of what the current ‘best practices’ are in the field. PMID:23832194

  12. Crystallization reports are the backbone of Acta Cryst. F, but do they have any spine?

    PubMed

    Newman, Janet; Burton, Denis R; Caria, Sofia; Desbois, Sebastien; Gee, Christine L; Fazio, Vincent J; Kvansakul, Marc; Marshall, Bevan; Mills, Grant; Richter, Viviane; Seabrook, Shane A; Wu, Mingbo; Peat, Thomas S

    2013-07-01

    Crystallization of macromolecules is famously difficult. By knowing what has worked for others, researchers can ease the process, both in the case where the protein has already been crystallized and in the situation where more general guidelines are needed. The 264 crystallization communications published in Acta Crystallographica Section F in 2012 have been reviewed, and from this analysis some information about trends in crystallization has been gleaned. More importantly, it was found that there are several ways in which the utility of these communications could be increased: to make each individual paper a more complete crystallization record; and to provide a means for taking a snapshot of what the current `best practices' are in the field. PMID:23832194

  13. Teaching and outreach in the Aula d'Astronomia of the Universitat de València: a lab for studying the heavens

    NASA Astrophysics Data System (ADS)

    Marco, E.; Ballesteros, F.

    2011-11-01

    The Aula d'Astronomia is a teaching laboratory of the Faculty of Physics, University of Valencia, managed by the Departamentd'Astronomia i Astrofísica. In it, practices of some astronomical specialities are taught. Therefore, we have a classroomwith computers together with four specific telescopes installed on the terrace (a solar one, a reflector with CCD, anapochromatic refractor and a radiotelescope). Apart from the academic aspect, the Aula d'Astronomia has been widely used foroutreach activities through various educational programs such as visits from elementary and high schools, the open dayConéixer la Universitat visits, the activities of the Week of Science, and public astronomy observation nights as theNits de divendres, nits d'estels. Finally, we should emphasize its use in important ephemerides such as the transit of Venus in 2004, the solar eclipse of 2005, or the open day activities of IYA2009. Located in the building Jeroni Muñoz at the Burjassot-Paterna Campus, since its inauguration in 1997, about 15000 people have used its facilities to attend classes, outreach lectures or make day and night observations.

  14. A Introdução de Astronomia Básica para Estudantes de 5 e 6 Séries do Ensino Fundamental

    NASA Astrophysics Data System (ADS)

    Gonzaga, E. P.; Voelzke, M. R.

    2008-09-01

    Com intuito de despertar o interesse pelo estudo da astronomia, desenvolveu-se entre 2003 e 2006 no Centro Educacional do Serviço Social da Indústria situado no município de Mauá, São Paulo, um trabalho com duração de 12 meses para turmas de 11 e 12 anos, sendo três turmas por período (2003 / 2004, 2004 / 2005 e 2005 / 2006). O trabalho realizado, objetivando a introdução da astronomia básica com observações de constelações e das fases da Lua, permitindo estender-se a outros corpos celestes, iniciou-se com visita ao planetário Mundo Estelar, localizado no Ipiranga, São Paulo levantou-se a questão da importância do estudo da astronomia e foi lançado aos estudantes um trabalho de observação, com a proposta de localizar as constelações e compreender as fases da Lua, para o registro de tais observações, foram distribuídos mapas celestes, pastas, planilhas de anotações com lacunas para, constelações, fases da Lua e relatos, onde os estudantes acrescentaram pesquisas e relatórios. Os resultados dos 346 estudantes foram que 86,7% (300) concluíram a etapa de observação, destes 300 estudantes 43,3% (130) pesquisaram sobre as constelações e 19,0% (57) localizaram até quatro constelações. Dos 346 estudantes, 44,2% (153) registraram as fases da Lua equivocadamente e 10,4% (36) anexaram reportagens sobre astronomia. Conclui-se que os estudantes se dividiram em pesquisadores, sendo os estudantes que registraram e anexaram informações e, os observadores que preencheram as planilhas de observações, além de desenvolverem habilidades e competências relacionadas ao estudo da astronomia.

  15. Avoidance of Autophagy Mediated by PlcA or ActA Is Required for Listeria monocytogenes Growth in Macrophages

    PubMed Central

    Mitchell, Gabriel; Ge, Liang; Huang, Qiongying; Chen, Chen; Kianian, Sara; Roberts, Mary F.; Schekman, Randy

    2015-01-01

    Listeria monocytogenes is a facultative intracellular pathogen that escapes from phagosomes and grows in the cytosol of infected host cells. Most of the determinants that govern its intracellular life cycle are controlled by the transcription factor PrfA, including the pore-forming cytolysin listeriolysin O (LLO), two phospholipases C (PlcA and PlcB), and ActA. We constructed a strain that lacked PrfA but expressed LLO from a PrfA-independent promoter, thereby allowing the bacteria to gain access to the host cytosol. This strain did not grow efficiently in wild-type macrophages but grew normally in macrophages that lacked ATG5, a component of the autophagy LC3 conjugation system. This strain colocalized more with the autophagy marker LC3 (42% ± 7%) at 2 h postinfection, which constituted a 5-fold increase over the colocalization exhibited by the wild-type strain (8% ± 6%). While mutants lacking the PrfA-dependent virulence factor PlcA, PlcB, or ActA grew normally, a double mutant lacking both PlcA and ActA failed to grow in wild-type macrophages and colocalized more with LC3 (38% ± 5%). Coexpression of LLO and PlcA in a PrfA-negative strain was sufficient to restore intracellular growth and decrease the colocalization of the bacteria with LC3. In a cell-free assay, purified PlcA protein blocked LC3 lipidation, a key step in early autophagosome biogenesis, presumably by preventing the formation of phosphatidylinositol 3-phosphate (PI3P). The results of this study showed that avoidance of autophagy by L. monocytogenes primarily involves PlcA and ActA and that either one of these factors must be present for L. monocytogenes growth in macrophages. PMID:25776746

  16. Tendências De Teses e Dissertações Sobre Educação em Astronomia No Brasil

    NASA Astrophysics Data System (ADS)

    Bretones, Paulo Sergio; Megid Neto, Jorge

    2005-07-01

    Apresentam-se os resultados de uma pesquisa do tipo estado da arte sobre teses e dissertações defendidas no Brasil e relativas ao ensino de Astronomia, com objetivo de identificar essa produção e conhecer as principais tendências da pesquisa nesse campo. Foram localizadas 13 dissertações de mestrado e 3 teses de doutorado, as quais foram estudadas em função dos seguintes aspectos: isntituição, ano de defesa, nível escolar abrangido no estudo, foco temático do estudo e gênero de trabalho acadêmico. Pretende-se assim colaborar com a divulgação ampla da produção acadêmica na área. Ao mesmo tempo o estudo possibilita, a partir de investigações decorrentes, apontar as contribuições dessa produção para o ensino e sinalizar com necessidades a serem supridas por futuras pesquisas.

  17. Modelo de accesibilidad de conceptos matematicos aplicados en el curso de Astronomia Descriptiva para estudiantes con impedimentos visuales en la UPR

    NASA Astrophysics Data System (ADS)

    Isidro Villamizar, Gloria Maria

    Este estudio utiliza metodologia de investigacion cualitativa, con el proposito de describir, analizar y evaluar los procesos de diseno y desarrollo de un modelo de accesibilidad que consiste en estrategias de ensenanza de las matematicas para estudiantes con impedimentos visuales matriculados en el curso de Astronomia Descriptiva en la UPR. Se utilizaron las siguientes estrategias para recopilar la informacion, 1) reflexiones de la investigadora en el proceso de diseno y desarrollo de las lecciones adaptadas, que se registraron en un diario reflexivo. 2) entrevista semiestructurada luego de haber trabajado las lecciones de aprendizaje adaptadas con los participantes. 3) observaciones y notas de la investigadora del trabajo de los participantes. Para obtener la informacion de los participantes se obtuvo los permisos institucionales necesarios; se seleccionaron los participantes y se validaron los instrumentos; se realizo el desarrollo de las lecciones adaptadas con los participantes; y finalmente, se analizo la informacion obtenida. El diseno de las lecciones de aprendizaje adaptadas se hizo siguiendo las recomendaciones curriculares de los temas de matematicas aplicados en el curso de Astronomia Descriptiva realizado por la investigadora durante su semestre de internado. El testimonio de las voces de los participantes se obtuvo del proceso de desarrollo de las lecciones de aprendizaje adaptadas de temas seleccionados de conceptos matematicos requeridos en el curso de Astronomia Descriptiva y de la entrevista semiestructurada con los participantes, luego de haber trabajado las lecciones de aprendizaje. Para el desarrollo de las lecciones de aprendizaje, se utilizaron materiales tactiles adaptados, materiales tactiles disenados y materiales disponibles comercialmente. Los textos de las lecciones se imprimieron en tinta y en Braille. Se exhorta a disenar y desarrollar estrategias de ensenanza accesibles, considerando como recursos para evaluar su efectividad a

  18. Celebrating 400 Years of Astronomia Nova: Johannes Kepler, the Kepler Mission, and the International Year of Astronomy

    NASA Astrophysics Data System (ADS)

    DeVore, Edna; Koch, D.; Gould, A.; Harman, P.

    2009-01-01

    The International Year of Astronomy 2009 is an occasion to celebrate astronomy around the world. In addition to honoring Galileo and the invention of the astronomical telescope, 2009 is the 400th anniversary year of Kepler's publication of the Astronomia Nova containing his first two laws of planetary motion. In recognition of Kepler's accomplishment, the first NASA mission capable of detecting Earth-size and smaller planets in the habitable zone of stars has been named after Johannes Kepler. The Kepler Mission launches in the spring of 2009 and will search for evidence of extrasolar planets as they transit--pass in front of--their parent stars. Using Kepler's Laws, scientists will interpret the Mission data to characterize the planets that are discovered. The Kepler Mission is conducting several Educational and Public Outreach (E/PO) activities leading up to and during IYA. Among these are the "Name In Space” project which offers participants the opportunity to send their name into space along with a statement about the importance of searching for extrasolar Earths. The "Kepler Star Wheel” (planisphere) shows both the Kepler field of view and naked eye stars with known planetary systems. A series of StarDate programs will be broadcast in English and Spanish. Inquiry-based classroom lessons suitable for middle and high school science classes are available for download at the website, and on the Kepler Mission poster. The Kepler Mission poster will be distributed to middle and high school science teachers through the National Science Teacher's Association and other science teacher organizations. Copies will be available at AAS. The Kepler EPO team is presenting pre-launch teacher workshops at several locations around the US. Details about the workshop, and event timeline will be presented. For further information on the Kepler Mission, its E/PO program, and online resources, please visit: http://kepler.nasa.gov. Funded by NASA's Science Mission Directorate.

  19. Celebrating 400 Years of Astronomia Nova: Johannes Kepler, the Kepler Mission, and the International Year of Astronomy

    NASA Astrophysics Data System (ADS)

    Devore, E. K.; Koch, D.; Gould, A.; Harman, P. K.

    2008-12-01

    The International Year of Astronomy 2009 is an occasion to celebrate astronomy around the world. In addition to honoring Galileo and the invention of the astronomical telescope, 2009 is the 400th anniversary year of Kepler's publication of the Astronomia Nova containing his first two laws of planetary motion. In recognition of Kepler's accomplishment, the first NASA mission capable of detecting Earth-size and smaller planets in the habitable zone of stars has been named after Johannes Kepler. The Kepler Mission launches in the spring of 2009 and will search for evidence of extrasolar planets as they transit--pass in front of--their parent stars. Using Kepler's Laws, scientists will interpret the Mission data to characterize the planets that are discovered. The Kepler Mission is conducting several Educational and Public Outreach (E/PO) activities leading up to and during IYA. Among these are the Name In Space project which offers participants the opportunity to send their name into space along with a statement about the importance of searching for extrasolar Earths. The Kepler Star Wheel (planisphere) shows both the Kepler field of view and naked eye stars with known planetary systems. A series of StarDate programs will be broadcast in English and Spanish. Inquiry-based classroom lessons suitable for middle and high school science classes are available for download at the website, and on the Kepler Mission poster. The Kepler Mission poster will be distributed to middle and high school science teachers through the National Science Teacher's Association and other science teacher organizations. Copies will be available at AGU. The Kepler EPO team is presenting pre-launch teacher workshops at several locations around the US. Details about the workshop, and event timeline will be presented. For further information on the Kepler Mission, its E/PO program, and online resources, please visit: http://Kepler.NASA.gov.

  20. Association of a Novel ACTA1 Mutation With a Dominant Progressive Scapuloperoneal Myopathy in an Extended Family

    PubMed Central

    Zukosky, Kristen; Meilleur, Katherine; Traynor, Bryan J.; Dastgir, Jahannaz; Medne, Livija; Devoto, Marcella; Collins, James; Rooney, Jachinta; Zou, Yaqun; Yang, Michele L.; Gibbs, J. Raphael; Meier, Markus; Stetefeld, Joerg; Finkel, Richard S.; Schessl, Joachim; Elman, Lauren; Felice, Kevin; Ferguson, Toby A.; Ceyhan-Birsoy, Ozge; Beggs, Alan H.; Tennekoon, Gihan; Johnson, Janel O.; Bönnemann, Carsten G.

    2015-01-01

    IMPORTANCE New genomic strategies can now be applied to identify a diagnosis in patients and families with previously undiagnosed rare genetic conditions. The large family evaluated in the present study was described in 1966 and now expands the phenotype of a known neuromuscular gene. OBJECTIVE To determine the genetic cause of a slowly progressive, autosomal dominant, scapuloperoneal neuromuscular disorder by using linkage and exome sequencing. DESIGN, SETTING, AND PARTICIPANTS Fourteen affected individuals in a 6-generation family with a progressive scapuloperoneal disorder were evaluated. Participants were examined at pediatric, neuromuscular, and research clinics from March 1, 2005, to May 31, 2014. Exome and linkage were performed in genetics laboratories of research institutions. MAIN OUTCOMES AND MEASURES Examination and evaluation by magnetic resonance imaging, ultrasonography, electrodiagnostic studies, and muscle biopsies (n = 3). Genetic analysis included linkage analysis (n = 17) with exome sequencing (n = 7). RESULTS Clinical findings included progressive muscle weakness in an initially scapuloperoneal and distal distribution, including wrist extensor weakness, finger and foot drop, scapular winging, mild facial weakness, Achilles tendon contractures, and diminished or absent deep tendon reflexes. Both age at onset and progression of the disease showed clinical variability within the family. Muscle biopsy specimens demonstrated type I fiber atrophy and trabeculated fibers without nemaline rods. Analysis of exome sequences within the linkage region (4.8 megabases) revealed missense mutation c.591C>A p.Glu197Asp in a highly conserved residue in exon 4 of ACTA1. The mutation cosegregated with disease in all tested individuals and was not present in unaffected individuals. CONCLUSIONS AND RELEVANCE This family defines a new scapuloperoneal phenotype associated with an ACTA1 mutation. A highly conserved protein, ACTA1 is implicated in multiple muscle

  1. Systematic mutational analysis of the amino-terminal domain of the Listeria monocytogenes ActA protein reveals novel functions in actin-based motility.

    PubMed

    Lauer, P; Theriot, J A; Skoble, J; Welch, M D; Portnoy, D A

    2001-12-01

    The Listeria monocytogenes ActA protein acts as a scaffold to assemble and activate host cell actin cytoskeletal factors at the bacterial surface, resulting in directional actin polymerization and propulsion of the bacterium through the cytoplasm. We have constructed 20 clustered charged-to-alanine mutations in the NH2-terminal domain of ActA and replaced the endogenous actA gene with these molecular variants. These 20 clones were evaluated in several biological assays for phenotypes associated with particular amino acid changes. Additionally, each protein variant was purified and tested for stimulation of the Arp2/3 complex, and a subset was tested for actin monomer binding. These specific mutations refined the two regions involved in Arp2/3 activation and suggest that the actin-binding sequence of ActA spans 40 amino acids. We also identified a 'motility rate and cloud-to-tail transition' region in which nine contiguous mutations spanning amino acids 165-260 caused motility rate defects and changed the ratio of intracellular bacteria associated with actin clouds and comet tails without affecting Arp2/3 activation. Several unusual motility phenotypes were associated with amino acid changes in this region, including altered paths through the cytoplasm, discontinuous actin tails in host cells and the tendency to 'skid' or dramatically change direction while moving. These unusual phenotypes illustrate the complexity of ActA functions that control the actin-based motility of L. monocytogenes. PMID:11886549

  2. Ensino de astronomia e óptica: é possível fazê-lo de forma contextualizada no nível médio?

    NASA Astrophysics Data System (ADS)

    Sobrinho, A. A.; Jafelice, L. C.

    2003-08-01

    Discutimos nossa participação em um curso de treinamento para professores de diversas disciplinas do ensino médio. Nossa preocupação básica foi desenvolver instrumentos educacionais adequados para levar à sala de aula, nesse nível de ensino, de forma contextualizada, questionamentos freqüentes dos alunos sobre astronomia e sua relação com tecnologia e sociedade. Encaminhamos questões como: a evolução da astronomia, suas relações com outros ramos do conhecimento humano e conseqüentes aplicações; avanços na tecnologia dos instrumentos ópticos versus a importância da observação do céu a olho nu; a relação entre olho humano, luneta e telescópio; e desenvolvimento da tecnologia espacial e sua influência em nosso cotidiano. Objetivamos com isto fazer um resgate histórico e pedagógico das aplicações e observações do céu no cenário escolar, destacando a relação entre eventos astronômicos, olho humano, instrumentos mediadores e suas contextualizações históricas e sociais. Produtos desta abordagem foram o desenvolvimento e a adaptação de práticas e materiais instrucionais diversos (e.g., "espelhos" de isopor e "raios luminosos" de bolinhas de gude; montagens envolvendo velas, lasers, lentes e espelhos; desmonte e análise de peças de um telescópio; etc.). Além disto, como outro resultado deste trabalho, elaboramos textos sobre história da astronomia e da óptica para atividades em classe. Com estas ações visamos facilitar a concretização de conceitos físicos envolvidos, exemplificar um ensino contextualizado e interdisciplinar motivado por temas astronômicos e favorecer que práticas e discussões feitas com os treinandos possam ser transpostas para a sala de aula. A reação dos professores às práticas propostas foi bastante positiva. Todos esses aspectos são discutidos em detalhe neste trabalho. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

  3. Imagens do céu ontem e hoje - um multimídia interativo de astronomia e uma nova exposição no MAST

    NASA Astrophysics Data System (ADS)

    Caretta, C. A.; Lima, F. P.; Requeijo, F.; Vieira, G. G.; Alves, F.; Valente, M. E. A.; de Almeida, R.; de Garcia, G. C.; Quixadá, A. C.

    2003-08-01

    "Imagens do Céu Ontem e Hoje" é o título de uma nova exposição que está sendo inaugurada no Museu de Astronomia e Ciências Afins (MCT), que inclui experimentos interativos, maquetes, réplicas e 8 terminais de computador com um multimídia interativo sobre Astronomia para consulta dos visitantes. O multimídia apresenta um conteúdo bastante extenso, que engloba quase todos os temas em Astronomia, consistindo numa fonte de divulgação e pesquisa para um público que vai das crianças até estudantes universitários. O conteúdo está distribuído em mais de 500 páginas de texto divididas em 4 módulos: "O Universo", "Espectroscopia", "Telescópios" e "Observando o Céu". Cada módulo é subdividido em 5 seções, em média, cada uma iniciada por uma animação que ilustra os temas a serem abordados na seção. Ao final da animação, uma lista de temas é apresentada sob o título "Saiba Mais". Para exemplificar, o módulo "O Universo" contém as seguintes seções: "O Universo visto pelo homem", "Conhecendo o Sistema Solar", "Indo além do Sistema Solar", "Nossa Galáxia, a Via-Láctea" e "Indo mais além, a imensidão do Universo". A seção "Conhecendo o Sistema Solar", por sua vez, tem os seguintes temas: "A origem do Sistema Solar", "O Sol", "Os planetas", "Satélites, asteróides, cometas e outros bichos..." e "O Sistema Solar em números". Cada texto é repleto de imagens, quadros, desenhos, esquemas, etc, além de passatempos ao final de cada seção, incluindo jogos interativos, quadrinhos e curiosidades, que auxiliam o aprendizado de forma divertida. Apresentamos neste trabalho as idéias gerais que permearam a produção da exposição, e uma viagem pelo multimídia para exemplificar sua estrutura e conteúdo. O multimídia será posteriormente disponibilizado para o público externo pela página eletrônica do MAst e/ou por intermédio de uma publicação comercial.

  4. Electrostatic and Hydrophobic Interactions Mediate Single-Stranded DNA Recognition and Acta2 Repression by Purine-Rich Element-Binding Protein B.

    PubMed

    Rumora, Amy E; Ferris, Lauren A; Wheeler, Tamar R; Kelm, Robert J

    2016-05-17

    Myofibroblast differentiation is characterized by an increased level of expression of cytoskeletal smooth muscle α-actin. In human and murine fibroblasts, the gene encoding smooth muscle α-actin (Acta2) is tightly regulated by a network of transcription factors that either activate or repress the 5' promoter-enhancer in response to environmental cues signaling tissue repair and remodeling. Purine-rich element-binding protein B (Purβ) suppresses the expression of Acta2 by cooperatively interacting with the sense strand of a 5' polypurine sequence containing an inverted MCAT cis element required for gene activation. In this study, we evaluated the chemical basis of nucleoprotein complex formation between the Purβ repressor and the purine-rich strand of the MCAT element in the mouse Acta2 promoter. Quantitative single-stranded DNA (ssDNA) binding assays conducted in the presence of increasing concentrations of monovalent salt or anionic detergent suggested that the assembly of a high-affinity nucleoprotein complex is driven by a combination of electrostatic and hydrophobic interactions. Consistent with the results of pH titration analysis, site-directed mutagenesis revealed several basic amino acid residues in the intermolecular (R267) and intramolecular (K82 and R159) subdomains that are essential for Purβ transcriptional repressor function in Acta2 promoter-reporter assays. In keeping with their diminished Acta2 repressor activity in fibroblasts, purified Purβ variants containing an R267A mutation exhibited reduced binding affinity for purine-rich ssDNA. Moreover, certain double and triple-point mutants were also defective in binding to the Acta2 corepressor protein, Y-box-binding protein 1. Collectively, these findings establish the repertoire of noncovalent interactions that account for the unique structural and functional properties of Purβ. PMID:27064749

  5. Twenty Years of Society of Medical Informatics of B&H and the Journal Acta Informatica Medica

    PubMed Central

    Masic, Izet

    2012-01-01

    In 2012, Health/Medical informatics profession celebrates five jubilees in Bosnia and Herzegovina: a) Thirty five years from the introduction of the first automatic manipulation of data; b) Twenty five years from establishing Society for Medical Informatics BiH; c) Twenty years from establishing scientific and professional journal of the Society for Medical Informatics of Bosnia and Herzegovina „Acta Informatica Medica“; d) Twenty years from establishing first Cathdra for Medical Informatics on biomedical faculties in Bosnia and Herzegovina and e) Ten years from the introduction of “Distance learning” in medical curriculum. All of the five mentioned activities in the area of Medical informatics had special importance and gave appropriate contribution in the development of Health/Medical informatics in Bosnia And Herzegovina. PMID:23322947

  6. The απολογητοσ-riddle in Kepler's Astronomia Nova, chapter 57. (German Title: Das απολογητοσ-Rätsel in Keplers Astronomia Nova, Kapitel 57)

    NASA Astrophysics Data System (ADS)

    Kühn, Ernst

    Since 1937, the latin edition of Johannes Kepler's Astronomia Nova (1609) is available as a standard text. Here, in the 57th chapter, the third one of 48 important marginalia of Kepler, is reproduced as ⪉quo;Quae sit genuina et απολογητοσ mensura librationis huijus etc.». The Grecized word «αpi;ολογητοσ» was ignored to a large extent by translators and commentators, and was at least declared enigmatic by Donahue (1992). A look in the original copies of the 1609 edition shows that it is written ατιολογητοσ, not π but a τι. απολογητοσ in KGW is a read error. In the context of Keplers «natural, causal magnet-like forcesraquo; of planetary motion the conjecture αιτιολογητοσ (as a typographical error a ι is omitted) immediately suggests itself: causally, aetiological. This solution of the απολογητοσ riddle indicates the tight brace between the important Chapter 57 of Kepler's celestial physics and and the complete title ASTRONOMIA NOVA ΑΙΤΙΟΛΟΓΗΤΟΣ, SEV PHYSICA COELESTIS etc.

  7. Streptomyces rochei ACTA1551, an Indigenous Greek Isolate Studied as a Potential Biocontrol Agent against Fusarium oxysporum f.sp. lycopersici

    PubMed Central

    Kanini, Grammatiki S.; Katsifas, Efstathios A.; Savvides, Alexandros L.; Karagouni, Amalia D.

    2013-01-01

    Many studies have shown that several Greek ecosystems inhabit very interesting bacteria with biotechnological properties. Therefore Streptomyces isolates from diverse Greek habitats were selected for their antifungal activity against the common phytopathogenic fungus Fusarium oxysporum. The isolate encoded ACTA1551, member of Streptomyces genus, could strongly suppress the fungal growth when examined in antagonistic bioassays in vitro. The isolate was found phylogenetically relative to Streptomyces rochei after analyzing its 16S rDNA sequence. The influence of different environmental conditions, such as medium composition, temperature, and pH on the expression of the antifungal activity was thoroughly examined. Streptomyces rochei ACTA1551 was able to protect tomato seeds from F. oxysporum infection in vivo while it was shown to promote the growth of tomato plants when the pathogen was absent. In an initial effort towards the elucidation of the biochemical and physiological nature of ACTA1551 antifungal activity, extracts from solid streptomycete cultures under antagonistic or/and not antagonistic conditions were concentrated and fractionated. The metabolites involved in the antagonistic action of the isolate showed to be more than one and produced independently of the presence of the pathogen. The above observations could support the application of Streptomyces rochei ACTA1551 as biocontrol agent against F. oxysporum. PMID:23762841

  8. The beginnings of Acta Neurochirurgica and the work of Fritz Loew, chief editor from 1958 - 1997. An historical vignette.

    PubMed

    Reulen, Hans-Jürgen; Collmann, Hartmut

    2012-07-01

    Acta Neurochirurgica was founded in 1950, in the difficult time after World War II, by Mario Milletti (Bologna) and Wolfram Sorgo (Innsbruck), and published by Springer press, Vienna. From the beginning the new journal was conceived as an international journal with an impressive list of outstanding neurosurgeons in the editorial board. Only a few years later the issues appeared at irregular intervals due to individual problems of both editors. Wilhelm Tönnis took the initiative to keep the journal alive, when he asked-in consent with Springer press-his staff member Fritz Loew to continue the editorial work and to assemble a new prestigious editorial board. Loew succeeded with both tasks and remained editor-in-chief for nearly 38 years. Initially, all papers were published in the native languages of the authors: English, French, German, Italian and Spanish. With ongoing time the journal accepted manuscripts in English only. The slow progress of this process exemplifies the slow integration of the European countries. In 1971, at the founding meeting of the European Association of Neurosurgical Societies (EANS) in Prague, Acta Neurochirurgica became the official organ of the EANS. Right from the beginning of Acta Neurochirurgica, Supplement volumes were added. Also, the book series Advances and Technical Standards in Neurosurgery is an offspring of Acta Neurochirurgica. Acta Neurochirurgica has become one of the most important neurosurgical journals worldwide. This historical sketch is based on an interview with Fritz Loew, now 91 years old, to which data from the available literature and the Archives of German Neurosurgery, as well as personal information by several colleagues were added. PMID:22581432

  9. Treatment with ActRIIB-mFc Produces Myofiber Growth and Improves Lifespan in the Acta1 H40Y Murine Model of Nemaline Myopathy.

    PubMed

    Tinklenberg, Jennifer; Meng, Hui; Yang, Lin; Liu, Fujun; Hoffmann, Raymond G; Dasgupta, Mahua; Allen, Kenneth P; Beggs, Alan H; Hardeman, Edna C; Pearsall, R Scott; Fitts, Robert H; Lawlor, Michael W

    2016-06-01

    Nemaline myopathies (NMs) are a group of congenital muscle diseases caused by mutations in at least 10 genes and associated with a range of clinical symptoms. NM is defined on muscle biopsy by the presence of cytoplasmic rod-like structures (nemaline rods) composed of cytoskeletal material. Myofiber smallness is also found in many cases of NM and may represent a cause of weakness that can be counteracted by treatment. We have used i.p. injection of activin type IIB receptor (ActRIIB)-mFc (an inhibitor of myostatin signaling) to promote hypertrophy and increase strength in our prior murine work; we therefore tested whether ActRIIB-mFc could improve weakness in NM mice through myofiber hypertrophy. We report a study of ActRIIB-mFc treatment in the Acta1 H40Y mouse model of NM. Treatment of Acta1 H40Y mice produced significant increases in body mass, muscle mass, quadriceps myofiber size, and survival, but other measurements of strength (forelimb grip strength, ex vivo measurements of contractile function) did not improve. Our studies also identified that the complications of urethral obstruction are associated with mortality in male hemizygote Acta1 H40Y mice. The incidence of urethral obstruction and histologic evidence of chronic obstruction (inflammation) were significantly lower in Acta1 H40Y mice that had been treated with ActRIIB-mFc. ActRIIB-mFc treatment produces a mild benefit to the disease phenotype in Acta1 H40Y mice. PMID:27102768

  10. Disciplines and Professors of Astronomy in Undergraduate Physics Teachers Formation Courses in Brazilian Universities. (Spanish Title: Disciplinas y Profesores de Astronomia en los Cursos de Licenciatura en Física en Las Universidades Brasileñas.) Disciplinas e Professores de Astronomia Nos Cursos de Licenciatura em Física das Universidades Brasileiras

    NASA Astrophysics Data System (ADS)

    Roberto, Artur Justiniano, Jr.; Reis, Thiago Henrique; dos Reis Germinaro, Daniel

    2014-12-01

    formación. Aparte de eso, los datos levantados en este trabajo apuntan para un número bajo de afiliados a la SAB (Sociedade Astronômica Brasileira) en los cursos investigados. Se verificó que tener astrónomos en una institución no implica tener una disciplina obligatoria de Astronomía en el curso de licenciatura en Física. Este artigo é o resultado de uma pesquisa sobre a formação básica em Astronomia nos cursos de Licenciatura em Física que fizeram o exame nacional ENADE 2011. O objetivo do trabalho foi identificar se há disciplinas de Astronomia nesses cursos, se ela é obrigatória ou optativa/eletiva, qual a sua carga horária e o período em que é oferecida. Pesquisou-se também a relação entre astrônomos, cursos de Licenciatura em Física e disciplinas de Astronomia. Para realizar essa pesquisa utilizamos os dados do ENADE 2011 e também do censo da Astronomia brasileira. Como resultado, se observa que em apenas 15% dos cursos existe uma disciplina obrigatória de Astronomia e que há uma grande probabilidade de que 85% dos professores de Física formados em 2011 não cursaram nenhuma disciplina de Astronomia durante a graduação. Além disso, os dados levantados nesse trabalho apontam um baixo número de filiados à SAB nos cursos pesquisados. Identifica-se que ter astrônomos na instituição não implica em disciplina obrigatória de Astronomia no curso de Licenciatura em Física.

  11. The Teaching of Astronomy in Uruguay. (Spanish Title: La Enseñanza de la Astronomía en Uruguay.) O Ensino da Astronomia no Uruguai

    NASA Astrophysics Data System (ADS)

    Pintos Ganón, Reina; Fernández, Julio Angel

    2008-07-01

    We present in this work the development of astronomy in Uruguay since the colony times up to the present, stressing in particular those aspects related to the formal as well as informal teaching of astronomy. The first antecedents of astronomical studies in our country go back to the beginnings of the XVIIIth century related to the scientific expeditions from Europe coming to our shores. The teaching of astronomy was generalized at the high school level as soon as the end of the XIXth century, while itsintroduction at the university level happened much later, around the middle of the last century. We analyze the current situation of this subject, its problems, and some measures to strengthen its development. Se presenta en este trabajo el desarrollo de la astronomía en el Uruguay desde la época colonial hasta el presente, destacando en particular los aspectos vinculados a su enseñanza tanto formal como informal. Los primeros antecedentes de estudios astronómicos datan de la época colonial relacionados con las expediciones científicas del Viejo Mundo que llegaban a nuestras costas. La enseñanza de la Astronomía se generalizó en el ámbito de los estudios secundarios ya a fines del siglo XIX, mientras que en la Universidad su arribo fue mucho más tardío, a mediados del siglo pasado. Se analiza la situación actual de esta disciplina, sus problemas, y algunas medidas para fortalecer su desarrollo. Apresentamos, neste trabalho, o desenvolvimento da Astronomia no Uruguai desde a época colonial até o presente, destacando em particular os aspectos vinculados ao seu ensino tanto formal quanto informal. Os primeiros antecedentes de estudos astronômicos em nosso país datam da época colonial relacionados com as expedições científicas do Velho Mundo que chegavam às nossas costas. O ensino da Astronomia se generalizou no âmbito dos estudos secundários já no final do século XIX, enquanto que sua introdução na universidade foi muito mais tardia, em

  12. Vascular disease-causing mutation R258C in ACTA2 disrupts actin dynamics and interaction with myosin

    PubMed Central

    Lu, Hailong; Fagnant, Patricia M.; Bookwalter, Carol S.; Joel, Peteranne; Trybus, Kathleen M.

    2015-01-01

    Point mutations in vascular smooth muscle α-actin (SM α-actin), encoded by the gene ACTA2, are the most prevalent cause of familial thoracic aortic aneurysms and dissections (TAAD). Here, we provide the first molecular characterization, to our knowledge, of the effect of the R258C mutation in SM α-actin, expressed with the baculovirus system. Smooth muscles are unique in that force generation requires both interaction of stable actin filaments with myosin and polymerization of actin in the subcortical region. Both aspects of R258C function therefore need investigation. Total internal reflection fluorescence (TIRF) microscopy was used to quantify the growth of single actin filaments as a function of time. R258C filaments are less stable than WT and more susceptible to severing by cofilin. Smooth muscle tropomyosin offers little protection from cofilin cleavage, unlike its effect on WT actin. Unexpectedly, profilin binds tighter to the R258C monomer, which will increase the pool of globular actin (G-actin). In an in vitro motility assay, smooth muscle myosin moves R258C filaments more slowly than WT, and the slowing is exacerbated by smooth muscle tropomyosin. Under loaded conditions, small ensembles of myosin are unable to produce force on R258C actin-tropomyosin filaments, suggesting that tropomyosin occupies an inhibitory position on actin. Many of the observed defects cannot be explained by a direct interaction with the mutated residue, and thus the mutation allosterically affects multiple regions of the monomer. Our results align with the hypothesis that defective contractile function contributes to the pathogenesis of TAAD. PMID:26153420

  13. Vascular disease-causing mutation R258C in ACTA2 disrupts actin dynamics and interaction with myosin.

    PubMed

    Lu, Hailong; Fagnant, Patricia M; Bookwalter, Carol S; Joel, Peteranne; Trybus, Kathleen M

    2015-08-01

    Point mutations in vascular smooth muscle α-actin (SM α-actin), encoded by the gene ACTA2, are the most prevalent cause of familial thoracic aortic aneurysms and dissections (TAAD). Here, we provide the first molecular characterization, to our knowledge, of the effect of the R258C mutation in SM α-actin, expressed with the baculovirus system. Smooth muscles are unique in that force generation requires both interaction of stable actin filaments with myosin and polymerization of actin in the subcortical region. Both aspects of R258C function therefore need investigation. Total internal reflection fluorescence (TIRF) microscopy was used to quantify the growth of single actin filaments as a function of time. R258C filaments are less stable than WT and more susceptible to severing by cofilin. Smooth muscle tropomyosin offers little protection from cofilin cleavage, unlike its effect on WT actin. Unexpectedly, profilin binds tighter to the R258C monomer, which will increase the pool of globular actin (G-actin). In an in vitro motility assay, smooth muscle myosin moves R258C filaments more slowly than WT, and the slowing is exacerbated by smooth muscle tropomyosin. Under loaded conditions, small ensembles of myosin are unable to produce force on R258C actin-tropomyosin filaments, suggesting that tropomyosin occupies an inhibitory position on actin. Many of the observed defects cannot be explained by a direct interaction with the mutated residue, and thus the mutation allosterically affects multiple regions of the monomer. Our results align with the hypothesis that defective contractile function contributes to the pathogenesis of TAAD. PMID:26153420

  14. Host cell heparan sulfate proteoglycans mediate attachment and entry of Listeria monocytogenes, and the listerial surface protein ActA is involved in heparan sulfate receptor recognition.

    PubMed

    Alvarez-Domínguez, C; Vázquez-Boland, J A; Carrasco-Marín, E; López-Mato, P; Leyva-Cobián, F

    1997-01-01

    The mechanisms by which the intracellular pathogen Listeria monocytogenes interacts with the host cell surface remain largely unknown. In this study, we investigated the role of heparan sulfate proteoglycans (HSPG) in listerial infection. Pretreatment of bacteria with heparin or heparan sulfate (HS), but not with other glycosaminoglycans, inhibited attachment and subsequent uptake by IC-21 murine macrophages and CHO epithelial-like cells. Specific removal of HS from target cells with heparinase III significantly impaired listerial adhesion and invasion. Mutant CHO cells deficient in HS synthesis bound and internalized significantly fewer bacteria than wild-type cells did. Pretreatment of target cells with the HS-binding proteins fibronectin and platelet factor 4, or with heparinase III, impaired listerial infectivity only in those cells expressing HS. Moreover, a synthetic peptide corresponding to the HS-binding ligand in Plasmodium falciparum circumsporozoite protein (pepPf1) inhibited listerial attachment to IC-21 and CHO cells. A motif very similar to the HS-binding site of pepPf1 was found in the N-terminal region of ActA, the L. monocytogenes surface protein responsible for actin-based bacterial motility and cell-to-cell spread. In the same region of ActA, several clusters of positively charged amino acids which could function as HS-binding domains were identified. An ActA-deficient mutant was significantly impaired in attachment and entry due to altered HS recognition functions. This work shows that specific interaction with an HSPG receptor present on the surface of both professional and nonprofessional phagocytes is involved in L. monocytogenes cytoadhesion and invasion and strongly suggests that the bacterial surface protein ActA may be a ligand mediating HSPG receptor recognition. PMID:8975895

  15. Combined MRI and 31P-MRS Investigations of the ACTA1(H40Y) Mouse Model of Nemaline Myopathy Show Impaired Muscle Function and Altered Energy Metabolism

    PubMed Central

    Gineste, Charlotte; Le Fur, Yann; Vilmen, Christophe; Le Troter, Arnaud; Pecchi, Emilie; Cozzone, Patrick J.; Hardeman, Edna C.; Bendahan, David; Gondin, Julien

    2013-01-01

    Nemaline myopathy (NM) is the most common disease entity among non-dystrophic skeletal muscle congenital diseases. Mutations in the skeletal muscle α-actin gene (ACTA1) account for ∼25% of all NM cases and are the most frequent cause of severe forms of NM. So far, the mechanisms underlying muscle weakness in NM patients remain unclear. Additionally, recent Magnetic Resonance Imaging (MRI) studies reported a progressive fatty infiltration of skeletal muscle with a specific muscle involvement in patients with ACTA1 mutations. We investigated strictly noninvasively the gastrocnemius muscle function of a mouse model carrying a mutation in the ACTA1 gene (H40Y). Skeletal muscle anatomy (hindlimb muscles and fat volumes) and energy metabolism were studied using MRI and 31Phosphorus magnetic resonance spectroscopy. Skeletal muscle contractile performance was investigated while applying a force-frequency protocol (from 1–150 Hz) and a fatigue protocol (80 stimuli at 40 Hz). H40Y mice showed a reduction of both absolute (−40%) and specific (−25%) maximal force production as compared to controls. Interestingly, muscle weakness was associated with an improved resistance to fatigue (+40%) and an increased energy cost. On the contrary, the force frequency relationship was not modified in H40Y mice and the extent of fatty infiltration was minor and not different from the WT group. We concluded that the H40Y mouse model does not reproduce human MRI findings but shows a severe muscle weakness which might be related to an alteration of intrinsic muscular properties. The increased energy cost in H40Y mice might be related to either an impaired mitochondrial function or an alteration at the cross-bridges level. Overall, we provided a unique set of anatomic, metabolic and functional biomarkers that might be relevant for monitoring the progression of NM disease but also for assessing the efficacy of potential therapeutic interventions at a preclinical level. PMID:23613869

  16. Multimodal MRI and 31P-MRS Investigations of the ACTA1(Asp286Gly) Mouse Model of Nemaline Myopathy Provide Evidence of Impaired In Vivo Muscle Function, Altered Muscle Structure and Disturbed Energy Metabolism

    PubMed Central

    Gineste, Charlotte; Duhamel, Guillaume; Le Fur, Yann; Vilmen, Christophe; Cozzone, Patrick J.; Nowak, Kristen J.; Bendahan, David; Gondin, Julien

    2013-01-01

    Nemaline myopathy (NM), the most common non-dystrophic congenital disease of skeletal muscle, can be caused by mutations in the skeletal muscle α-actin gene (ACTA1) (~25% of all NM cases and up to 50% of severe forms of NM). Muscle function of the recently generated transgenic mouse model carrying the human Asp286Gly mutation in the ACTA1 gene (Tg(ACTA1)Asp286Gly) has been mainly investigated in vitro. Therefore, we aimed at providing a comprehensive picture of the in vivo hindlimb muscle function of Tg(ACTA1)Asp286Gly mice by combining strictly noninvasive investigations. Skeletal muscle anatomy (hindlimb muscles, intramuscular fat volumes) and microstructure were studied using multimodal magnetic resonance imaging (Dixon, T2, Diffusion Tensor Imaging [DTI]). Energy metabolism was studied using 31-phosphorus Magnetic Resonance Spectroscopy (31P-MRS). Skeletal muscle contractile performance was investigated while applying a force-frequency protocol (1–150 Hz) and a fatigue protocol (6 min–1.7 Hz). Tg(ACTA1)Asp286Gly mice showed a mild muscle weakness as illustrated by the reduction of both absolute (30%) and specific (15%) maximal force production. Dixon MRI did not show discernable fatty infiltration in Tg(ACTA1)Asp286Gly mice indicating that this mouse model does not reproduce human MRI findings. Increased T2 values were observed in Tg(ACTA1)Asp286Gly mice and might reflect the occurrence of muscle degeneration/regeneration process. Interestingly, T2 values were linearly related to muscle weakness. DTI experiments indicated lower λ2 and λ3 values in Tg(ACTA1)Asp286Gly mice, which might be associated to muscle atrophy and/or the presence of histological anomalies. Finally 31P-MRS investigations illustrated an increased anaerobic energy cost of contraction in Tg(ACTA1)Asp286Gly mice, which might be ascribed to contractile and non-contractile processes. Overall, we provide a unique set of information about the anatomic, metabolic and functional consequences

  17. Estudo exaustivo e sistemático de erros nas provas da olimpíada brasileira de astronomia - resultados preliminares

    NASA Astrophysics Data System (ADS)

    Oliveira, F. S.; Canalle, J. B. G.; Villas da Rocha, J. F.

    2003-08-01

    A Olimpíada Brasileira de Astronomia (OBA) contou, em sua quinta edição, com a participação de mais de 60 mil alunos dos ensinos fundamental e médio de praticamente todo o território nacional. Uma das formas de controle que a sua coordenação nacional possui sobre a correção, levada a cabo pelos professores que as aplicaram, é a do envio, por parte destes professores, das 10 melhores provas de cada um dos três níveis nos quais a Olimpíada é realizada. Assim, e dado ao caráter discursivo das provas da Olimpíada, a sua coordenação nacional dispõe de um vasto acervo sobre as concepções, certas ou erradas, dos alunos que dela participaram. Este conjunto de dados jamais fora explorado até o presente trabalho que pretende ser, neste sentido, inaugural. Nas provas dos níveis I e II da V OBA, que abrangem todo o conjunto do ensino fundamental, uma das questões versava sobre a noção que os alunos tinham sobre como os habitantes da Terra situam-se sobre sua superfície. Fizemos um estudo sistemático das respostas a esta questão. Primeiramente, todas as modalidades de erros foram levantadas; em seguida, realizamos uma distribuição por idade tanto do índice de acerto como da ocorrência e da distribuição de cada erro. Como resultado, obtivemos que, em ambos os níveis: 1) as concepções errôneas não se apresentam distribuídas aleatoriamente; 2) há uma concentração no tipo de erro apresentado; 3) há uma tendência de progressivo acerto com relação à idade quando os dados são considerados em termos nacionais; 4) esta tendência nacional é fraca ou mesmo não é verificada em alguns dos estados com maior patamar de acerto.

  18. Uso de modelos mecânicos em curso informal de astronomia para deficientes visuais. Resgate de uma experiência

    NASA Astrophysics Data System (ADS)

    Tavares, E. T., Jr.; Klafke, J. C.

    2003-08-01

    O presente trabalho propõe-se a resgatar uma experiência que teve lugar no Planetário de São Paulo nos anos 60. Em 1962, o Sr. Acácio, então com 37 anos, deficiente visual desde os 27, passou a assistir às aulas ministradas pelo Prof. Aristóteles Orsini aos integrantes do corpo de servidores do Planetário. O Sr. Acácio era o único deficiente da turma e, embora possuísse conhecimentos básicos e relativamente avançados de matemática, enfrentava dificuldades na compreensão e acompanhamento da exposição, como também em estudos posteriores. Com o intuito de auxiliá-lo na superação desses problemas, o Prof. Orsini solicitou a construção de modelos mecânicos que, através do sentido do tato, permitissem o acompanhamento das aulas e a transposição do modelo para o "constructo" mental. Essa prática mostrou-se tão eficaz que facilitou sobejamente o aprendizado da matéria pelo sujeito. O Sr. Acácio passou a integrar o corpo de professores do Planetário/Escola Municipal de Astrofísica, tendo ficado responsável pelo curso de "Introdução à Astronomia" por vários anos. Além disso, a experiência foi tão bem sucedida que alguns dos modelos tiveram seus elementos constitutivos pintados diferencialmente para serem utilizados em cursos regulares do Planetário, tornando-se parte integrante do conjunto de recursos didáticos da instituição. É pensando nessa eficácia, tanto em seu objetivo original permitir o aprendizado de um deficiente visual quanto no subsidiário recurso didático sistemático da instituição que decidimos resgatar essa experiência. Estribados nela, acreditamos ser extremamente produtivo, em termos educacionais, o aperfeiçoamento dos modelos originais, agora resgatados e restaurados, e a criação de outros que pudessem ser utilizados no ensino dessa ciência a deficientes visuais.

  19. Astronomy in the Classroom: Why? (Spanish Title: Astronomía en la Clase: ¿Por Qué?) Astronomia na Sala de Aula: Por Quê?

    NASA Astrophysics Data System (ADS)

    Daros Gama, Leandro; Bagdonas Henrique, Alexandre

    2010-07-01

    particular, é foco deste ensaio: a astronomia. Em que sentido e em que medida valeria a pena abordá-la em aulas, seja de ciências, seja de astronomia especificamente, ou em disciplinas afins? Discutimos neste texto alguns aspectos das vantagens de se tratar essa área do conhecimento nas escolas, levando em conta as dimensões epistemológica e axiológica da astronomia, à luz da visão da ciência como um diálogo inteligente com o mundo, de Bachelard, além da proposta de problematização do conhecimento, de Paulo Freire. Proporemos que de fato a astronomia não precisa ser vista como apenas um novo conjunto de conteúdos a serem ensinados, mas figura como conjunto de temas motivadores para discussões histórico-filosóficas, além de permitir a abordagem de conceitos típicos de outras disciplinas.

  20. Learning Astronomy by Playing in a Park. (Spanish Title: Aprender AstronoMía Jugando en Una Plaza.) Aprender Astronomia Brincando em Uma Praça

    NASA Astrophysics Data System (ADS)

    Camino, Néstor

    2012-12-01

    trabalho alguns jogos de praça, considerados como módulos didáticos para imaginar processos astronômicos, a partir da concepção de que a aprendizagem em Astronomia deve-se desenvolver fortalecendo a relação do próprio corpo com o espaço tridimensional e com o tempo, tal como se vive ao observar o céu, construindo um "diálogo" entre o mundo real e as aprendizagens a construir. Os jogos apresentados (carrosséis e tobogãs) foram desenhados para trabalhar sobre a translação da Terra em torno do Sol, as fases da Lua e a gravidade, e sobre o que um observador percebe dos mesmos. Dá-se a descrição de cada jogo, discutem-se seus fundamentos físicos e astronômicos, e desenvolve-se uma crítica didática dos mesmos. Finalmente, comenta-se o papel que deveriam ter os docentes no apoio aos aprendizes no processo de interação com os jogos apresentados.

  1. Ensino de astronomia no 1o. e 2o. ciclos do nível fundamental e na educação de jovens e adultos: exemplos e discussões

    NASA Astrophysics Data System (ADS)

    Queiroz, A. S. B.; Jafelice, L. C.

    2003-08-01

    Tem-se constatado uma preocupante carência no ensino de astronomia nos diversos níveis de escolaridade. Neste trabalho discutimos várias práticas didático-pedagógicas que vimos desenvolvendo para crianças, jovens e adultos em processo de alfabetização, visando contribuir para reparar aquela carência. Propomos uma metodologia que incorpora as recentes exigências das políticas públicas educacionais, estimula o desenvolvimento de textos e materiais instrucionais, é compatível com a realidade desse público e é adaptável às respectivas faixas etárias. A observação do céu sempre esteve presente na vida de nossos antepassados, dando suporte à compreensão do ser humano como integrante da natureza. Visamos com este trabalho suprir a deficiência encontrada para se tratar a relação do ser humano com o céu, no ambiente escolar. Os resultados são animadores e envolvem práticas e textos que desenvolvemos e atividades realizadas pelos alunos. No primeiro grupo destacamos o desenvolvimento de várias práticas: "viagem aos planetas" (construímos o "foguete", os planetas em escala, contamos história e redigimos texto de orientação para os professores); "gnômon humano" (os próprios corpos dos alunos são usados para registrar o movimento aparente do Sol); "crateras da Lua" (concretização de "meteoritos" e "solo lunar" de gesso e exploração da relação entre energia cinética do bólido e tamanho da cratera formada); etc. No segundo grupo, produções de desenhos e redações e discussões dos alunos após a realização de cada prática, revelam que estas têm se mostrado muito eficientes, tanto para estimular a imaginação e a fantasia dos envolvidos, como para trabalhar-se habilidades, competências e conteúdos relacionados à astronomia, segundo uma perspectiva interdisciplinar contextualizada. (PPGECNM/UFRN; NUPA/USP; Temáticos/FAPESP)

  2. Acta Mechanica Sinica (selected articles)

    NASA Astrophysics Data System (ADS)

    Ling, G.; Yin, X.; Jiang, J.; Li, K.

    1982-08-01

    Selected articles on fluid mechanics and heat transfer are presented. Topics discussed are: (1) the secondary vortex and the karman vortex formation; (2) viscous compressible flow in turbomachinery; (3) partial differential equations satisfied by stream functions in three dimensional turbomachinery flow; and (4) iridium electrostatic probe and its application in a high temperature wind tunnel.

  3. Acta mechanica sinica (Selected articles)

    NASA Astrophysics Data System (ADS)

    Lian, J.; Lu, W.

    1984-05-01

    The coherent structure of a turbulent boundary layer at zero pressure gradient and for the gradient of adverse pressure was investigated. The hydrogen bubble method was employed to examine the turbulent flow in a two dimensional diffusion sector in a water channel. In a separate work, tensor calculus was used to derive three dimensional weak conservation form equations, time dependent flow surface iterative equations, and characteristic theory of non-orthogonal spherical coordinates. These equations and theory are useful in solving the three dimensional turbomachine transonic flow field.

  4. Acta Mechanica Sinica (selected articles)

    NASA Astrophysics Data System (ADS)

    Guocan, L.; Xieyuan, Y.

    1982-05-01

    Articles on the following topics are presented: the early stages of unsteady flow around a cylinder at high Reynolds number and under laminar conditions; methods for solving three dimensional flow in turbomachinery; numerical computation of viscous compressible flow in turbomachinery; a high speed interferograph system for investigating fast phenomena; and statistical simulation of the aerodynamic behavior of the transitional region of flow past combined bodies of revolution at arbitrary angles of attack.

  5. Basic Concepts of Astronomy: a Methodological Proposal. (Spanish Title: Conceptos Básicos de Astronomía: Una Propuesta Metodológica.) Conceitos Básicos de Astronomia: Uma Proposta Metodológica

    NASA Astrophysics Data System (ADS)

    Darroz, Luiz Marcelo; Heineck, Renato; Samudio Pérez, Carlos Ariel

    2011-12-01

    obtenidos en diferentes momentos, por los comentarios efectuados por los participantes durante las actividades y por los altos índices de aprobación al final de la etapa, consideramos que la propuesta atingió los objetivos establecidos y puede ser repetida con certeza de éxito. Neste relato, descreve-se o desenvolvimento de uma proposta metodológica que aborda conceitos básicos de astronomia fundamentada pedagogicamente na Aprendizagem Significativa. A proposta, que compreende quatro encontros, foi desenvolvida por professores e acadêmicos do curso de Licenciatura em Física da Universidade de Passo Fundo (UPF), através de um curso de extensão, a um grupo de dez estudantes do ensino médio de uma escola pública da cidade de Passo Fundo, RS. O trabalho centrou-se em conceitos básicos de astronomia. Os indícios da aprendizagem significativa foram obtidos por instrumentos de pesquisa e avaliação aplicados ao término de cada encontro. A avaliação da proposta foi efetuada através de um questionário final respondido pelos participantes ao término do desenvolvimento das atividades. Pelos resultados obtidos nos diferentes instrumentos, pelos comentários efetuados pelos participantes durante as atividades e pelos altos índices de aprovação alcançados no questionário final, consideramos que a proposta atingiu os objetivos estabelecidos e pode ser repetida com convicção de sucesso.

  6. Astronomy Teaching in Argentina in the 19th Century. (Spanish Title: La Enseñanza de la Astronomía en la Argentina del Siglo XIX.) O Ensino de Astronomia na Argentina no Século XIX

    NASA Astrophysics Data System (ADS)

    Norberto Cornejo, Jorge; Santilli, Haydée

    2010-12-01

    según el positivismo francés, y el segundo de acuerdo al positivismo alemán. También señalaremos la distinta actitud de ambos observatorios frente a la educación. En esta última dimensión veremos cómo las ideas positivistas tuvieron gran importancia en la formación de maestros impartida en las Escuelas Normales. Estableceremos también la relevante influencia del contexto socio-histórico en el desarrollo de la astronomía, y, a su vez, apreciaremos que esta última fue un actor social fundamental en la Historia Argentina. Domingo F. Sarmiento acreditava que a astronomia de Copérnico fosse uma das disciplinas científicas fundamentais para a formação de um cidadão "moderno". Neste trabalho estudaremos astronomia a partir de duas perspectivas: a científica e a educacional Nosso estudo será desenvolvido para a Argentina no século XIX, a partir da iniciativa de Bernardino Rivadavia, em 1821, que estabeleceu um observatório astronômico em Buenos Aires, até as primeiras atividades dos observatórios de Córdoba e La Plata. Em ambas as perspectivas, científica e educativa, vamos analisar a influência das ideias positivistas. Discutiremos como existiram diferenças epistemológicas entre eles, o Observatório de Córdoba orientado de acordo com o positivismo francês, e La Plata, de acordo com o positivismo alemão. Ambos os observatórios tinha uma atitude diferente em relação à educação. As ideias positivistas foram muito importantes para treinar professores do ensino primário na Argentina. Nós iremos enfatizar a importante influência do contexto sócio-histórico na astronomia, já que esta ciência foi um importante ator social na história da Argentina.

  7. Inclusion of Visually Impaired in the School Programme Scheduled Visit of the Museu de Astronomia e Ciências Afins (MAST). (Breton Title: Inclusão de Deficientes Visuais no Programa de Visita Escolar Programada do Museu de Astronomia e Ciências Afins (MAST).) Inclusión de Discapacitados Visuales en el Programa Escolar Programado del Museo de Astronomía y Ciencias Afines (MAST)

    NASA Astrophysics Data System (ADS)

    de Oliveira Gonçalves, Carla; da Conceição Barbosa-Lima, Maria

    2013-07-01

    Inclusive Education in Brazil, contemplated in the 1988 Constitution and in the Law of Guidelines and Bases of National Education (9.394/96) highlights the importance and urgency of promoting inclusive education as a formative element of nationality. Inclusive Education refers to all people who are struggling in school. Inclusion should be in all educational institutions (formal and informal). Our goal in the graduation final task was to report the experience of mediation to visually impaired students of the Instituto Benjamin Constant (IBC) at the Museu de Astronomia e Ciências Afins (MAST), and also suggest some modifications and present new proposals for the School Visit Program (VEP) through a specially constructed apparatus, where the sky can be sensed near the latitude of Rio de Janeiro. A educação inclusiva no Brasil, contemplada na Constituição de 1988 e a Lei de Diretrizes e Bases da Educação Nacional (9.394/96), destaca a importância e urgência de se promover a inclusão escolar como elemento formador da nacionalidade. A educação inclusiva diz respeito a todas as pessoas que enfrentam dificuldades na escola. A inclusão deve estar em todas as instituições educacionais (formais e não formais). Nosso objetivo, no trabalho de final de curso de licenciatura, foi apresentar o relato de experiência de mediação aos alunos deficientes visuais do Instituto Benjamin Constant (IBC) no Museu de Astronomia e Ciências Afins (MAST), as modificações e novas propostas para o Programa de Visita Escolar Programada (VEP) através de um aparelho especialmente construído onde se pode perceber o céu na latitude próxima a do Rio de Janeiro. La educación inclusiva en el Brasil, contemplada en la Constitución de 1988 y en la Ley de Directrices y Bases de la Educación Nacional (9.394/96), destaca la importancia y la urgencia de promover la inclusión escolar como elemento formador de la nacionalidad. La educación inclusiva se refiere a todas las personas

  8. Astronomy, Art and Mythology in a Public Elementary School in Itaocara/rj. (Spanish Title: Astronomía, Arte y Mitologia en el Ensino Fundamental en Una Escuela de la Red Estatal en ITAOCARA/RJ.) Astronomia, Arte e Mitologia no Ensino Fundamental em Escola da Rede Estadual em ITAOCARA/RJ

    NASA Astrophysics Data System (ADS)

    Oliveira Bernardes, Adriana; Ramos dos Santos, Arleidimar

    2008-12-01

    conocimientos recibidos. El trabajo en sí ha mostrado además de la posibilidad de la inclusión de la Astronomía en la Educación Primaria, la posibilidad de un trabajo interdisciplinario en los niveles iniciales incluyendo Astronomía, Arte y Mitología. Los resultados presentados por los estudiantes en las Olimpiadas promovidas en la escuela y por la OBA (Olimpiada Brasilera de Astronomía) permitieron verificar un creciente aprendizaje y estimulo hacia las materias científicas, comprobados por la apropiada expresión de los conceptos adquiridos de astronomía y presentados en evaluaciones o en informes obtenidos de ellos mismos, sus familias y profesores. Desenvolvendo um trabalho voluntário junto aos alunos do ensino fundamental no 1º ciclo (1ª a 4ª série), os monitores de Astronomia membros do CAIMP (Clube de Astronomia de Itaocara Marcos Pontes), que eram em sua maioria alunos do ensino médio, desenvolveram um trabalho de aproximação entre os alunos do Colégio Estadual Teotônio Brandão Vilela e os temas envolvendo Ciências e Astronomia. Através de oficinas de informática, artes, vídeos educativos e teatros de fantoches, os alunos puderam expressar seus conhecimentos e emoções diante das lendas mitológicas com as quais começaram a ter contato. O trabalho desenvolvido pelos monitores junto aos alunos proporcionou a integração entre as turmas do colégio e os levou a participação em atividades de maneira a estimular sua oralidade e aumentar sua auto-estima. Trabalhando várias formas de expressões, os alunos puderam realizar seus experimentos e conhecer alguns conceitos de Física e Astronomia, enquanto adquiriam autonomia para se expressarem de acordo com seus sentimentos e conhecimentos adquiridos. O trabalho em si mostrou além da possibilidade de inserção de Astronomia no Ensino Fundamental, a possibilidade de realização de um trabalho interdisciplinar nas séries iniciais envolvendo Astronomia, Arte e Mitologia. Os resultados apresentados

  9. The Science Teachers and Their way of Thinking about Astronomy. (Spanish Title: Los Profesores de Ciencias y Sus Formas de Pensar la Astronomía.) Os Professores de Ciências e Suas Formas de Pensar a Astronomia

    NASA Astrophysics Data System (ADS)

    Leite, Cristina; Hosoume, Yassuko

    2007-12-01

    ómicos y la estructura espacial del montaje del Universo son características fundamentales. Muchos indican Sol y estrellas como cosas distintas: el Sol es un objeto caliente y las estrellas son frías. Esos resultados nos preocupan y ciertamente señalan una urgencia de programas de formación continuada para profesores en el contenido de astronomía, pues los PCN's (Parámetros Curriculares Nacionales) recomiendan con énfasis la enseñanza de este contenido. O modo de pensar dos professores de Ciências do ensino fundamental sobre os elementos da Astronomia é o objeto de pesquisa presente neste artigo, cuja metodologia consiste em entrevistas semiestruturadas, filmadas em vídeo e centradas numa perspectiva tridimensional dos elementos astronômicos, possibilitando um mapeamento das concepções das formas e das dimensões da Terra, do Sol, da Lua, dos planetas e das estrelas, bem como da concepção de céu e de Universo como um todo. Os resultados indicam um Universo contendo: Sol, estrelas, planetas e Lua, onde o Sistema Solar é parte do todo. Algumas vezes o Universo é concebido como o próprio Sistema Solar. Os objetos estão no céu ou no Universo o qual, para muitos, se restringe ao espaço que está acima da Terra. A forma plana dos objetos astronômicos e a estrutura espacial da montagem do Universo são características marcantes. Muitos indicam Sol e estrelas como coisas diferentes: Sol é um objeto quente e as estrelas são frias. Esses resultados nos preocupam e certamente sinalizam uma urgência de programas de formação continuada para professores no conteúdo de astronomia, uma vez que os PCN's indicam fortemente o ensino desse conteúdo.

  10. La novela historica hispanoamericana actual: Carpentier, Fuentes y Galeano

    NASA Astrophysics Data System (ADS)

    Rivera-Ocasio, Gladys

    1998-10-01

    This dissertation studies the evolution of the historical novel in Spanish America during the second half of the twentieth century, focusing on the following works: El siglo de las luces (1962) by the Cuban Alejo Carpentier, Terra nostra (1975), by the Mexican Carlos Fuentes, and Memoria del fuego (1982-1986), by the Uruguayan Eduardo Galeano. The thesis' aim is to describe, analyze and suggest the causes for the breakdown of the modern historical narrative, decade by decade, from the sixties to the present. The line between what the dissertation identifies as modern and postmodern historical novels is drawn by radical changes in the structure of the aesthetic representation of history. Taking as its point of departure the implicit and sometimes explicit rules or poetics that conditioned the historical novel as a subgenre since Scott and Manzoni, the thesis explores how the new, postmodern novel, shatters the twin columns that supported that modern model: verisimilitude and linearity. This is the thesis's main work on the formal or aesthetic sphere of the recent Spanish American historical novel. But the aesthetic is intimately tied to two other spheres: the cosmological and the ontological (political and moral). If, on the one hand, the catastrophic state that the postmodern novel exhibits (the acceleration of its narrative particles, as it were) reveals itself as the mirror image of postmodern paradigms such as the fragment and catastrophe itself, on the other, its chaotic liberation reflects the historical ``spirit'' within it is produced. This is so because not only in its content, but also in its very form, the postmodern novel is part of that catastrophe. The postmodern novel's chaotic text posits the disintegration of all versionas of the emancipation project, or of the pursuit of an identity, that (the Cuban Revolution included) is closely allied to the totalizing drive that characterizes the spirit of modern times. The dissertation's hypothesis is that there is a link between the epistemological model of modern natural science and the modern historical novel. Hence that there is also a link between the postmodern paradigms (fragment, catastrophe) and the recent postmodern novel. The expansive, entropic, disconfluous and unpredictable universe of the ``New Physics'' is one with the nuclear catastrophe in Terra nostra, and with the fission-like explosion that pulverizes into minuscule units Galeanos's trilogy. The postmodern novel signals the end of the ontological project of man as subject for the good, which was correlative with the project of reason as the unifying and ordering force, prevalent since the Enlightenment. Criticism has noted that there has been a radical change in the historical novel, but has failed to speculate about its possible causes, not venturing beyond a mere catalogue of features. This dissertation aspires to go further by attempting to put forth the ideological, philosophical and even scientific reasons behind the change.

  11. Teaching of Astronomy: Scenarios of Teaching Practice in Elementary Schools. (Spanish Title: Enseñanza de la Astronomía: Semblanzas de la Práctica Docente en Educación Primaria.) Ensino de Astronomia: Cenários da Prática Docente no Ensino Fundamental

    NASA Astrophysics Data System (ADS)

    Marchi Gonzatti, Sônia Elisa; Spessatto De Maman, Andréia; Fernandes Borragini, Eliana; Kerber, Júlia Cristina; Haetinger, Werner

    2013-12-01

    atomización de los asuntos, aunque temas como movimientos de la Tierra y fenómenos astronómicos hayan sido citados por la mayoría de los participantes. En cuanto a las estrategias, se verifico que se emplean principalmente clases con el apoyo de recursos bidimensionales, como películas, textos, mapas y búsqueda en internet. Las principales dificultades fueron la falta de formación específica con respecto a los contenidos de Astronomía, y el nivel de abstracción exigido por los contenidos. De modo general, esos indicadores convergen para los resultados ya encontrados en otros estudios, en el que las deficiencias de la formación inicial de los profesores, o incluso su ausencia, dificulta el adecuado abordaje de la Astronomía en las clases. Neste trabalho são apresentados os principais resultados de uma investigação realizada no campo da Educação em Astronomia, com professores do ensino fundamental de duas regiões do Rio Grande do Sul. O objetivo do estudo foi caracterizar o cenário regional do ensino de Astronomia, estabelecendo um comparativo com o cenário nacional. Esse estudo abordou três questões: identificar os principais temas de astronomia trabalhados em sala de aula, as estratégias metodológicas e quais as dificuldades apresentadas pelos professores ao desenvolver sua prática. Quanto aos conteúdos, encontrouse uma pulverização dos assuntos abordados, embora temas como movimentos da Terra e fenômenos astronômicos tenham sido citados pela maioria dos participantes. Sobre estratégias, são utilizadas principalmente aulas com apoio de recursos bidimensionais, como filmes, textos, mapas e pesquisa na internet. As principais dificuldades foram: falta de formação específica em relação a conteúdos de Astronomia; nível de abstração dos conteúdos, que dificultam sua compreensão, tanto pelos alunos quanto pelos próprios professores. De maneira geral, esses indicadores convergem para resultados já encontrados em outros estudos que

  12. Astronomy, Art and Mythology in a Public Elementary School in Itaocara/rj. (Spanish Title: Astronomía, Arte y Mitologia en el Ensino Fundamental en Una Escuela de la Red Estatal en ITAOCARA/RJ.) Astronomia, Arte e Mitologia no Ensino Fundamental em Escola da Rede Estadual em ITAOCARA/RJ

    NASA Astrophysics Data System (ADS)

    Oliveira Bernardes, Adriana; Ramos dos Santos, Arleidimar

    2008-12-01

    conocimientos recibidos. El trabajo en sí ha mostrado además de la posibilidad de la inclusión de la Astronomía en la Educación Primaria, la posibilidad de un trabajo interdisciplinario en los niveles iniciales incluyendo Astronomía, Arte y Mitología. Los resultados presentados por los estudiantes en las Olimpiadas promovidas en la escuela y por la OBA (Olimpiada Brasilera de Astronomía) permitieron verificar un creciente aprendizaje y estimulo hacia las materias científicas, comprobados por la apropiada expresión de los conceptos adquiridos de astronomía y presentados en evaluaciones o en informes obtenidos de ellos mismos, sus familias y profesores. Desenvolvendo um trabalho voluntário junto aos alunos do ensino fundamental no 1º ciclo (1ª a 4ª série), os monitores de Astronomia membros do CAIMP (Clube de Astronomia de Itaocara Marcos Pontes), que eram em sua maioria alunos do ensino médio, desenvolveram um trabalho de aproximação entre os alunos do Colégio Estadual Teotônio Brandão Vilela e os temas envolvendo Ciências e Astronomia. Através de oficinas de informática, artes, vídeos educativos e teatros de fantoches, os alunos puderam expressar seus conhecimentos e emoções diante das lendas mitológicas com as quais começaram a ter contato. O trabalho desenvolvido pelos monitores junto aos alunos proporcionou a integração entre as turmas do colégio e os levou a participação em atividades de maneira a estimular sua oralidade e aumentar sua auto-estima. Trabalhando várias formas de expressões, os alunos puderam realizar seus experimentos e conhecer alguns conceitos de Física e Astronomia, enquanto adquiriam autonomia para se expressarem de acordo com seus sentimentos e conhecimentos adquiridos. O trabalho em si mostrou além da possibilidade de inserção de Astronomia no Ensino Fundamental, a possibilidade de realização de um trabalho interdisciplinar nas séries iniciais envolvendo Astronomia, Arte e Mitologia. Os resultados apresentados

  13. Astronomy in Science Textbooks: An Analysis of Pnld 2008. (Spanish Title: Astronomía en los Libros de Ciencia: un Análisis del Pnld 2008.) Astronomia Nos Livros Didáticos de Ciências: Uma Análise do Pnld 2008

    NASA Astrophysics Data System (ADS)

    Amaral, Patrícia; Quintanilha Vaz de Oliveira, Carlos Eduardo

    2011-12-01

    The importance of the textbooks in classrooms is revealed when studies are pointing that these pedagogical sources are, most of the times, the only source used by the elementary school teachers when preparing their Science lessons. When we analyzed the Astronomy contents in the textbooks approved by the Brazilian Textbook Program 2008 and which, in theory, are the best available in the Brazilian editorial market, we examined some categories in the 2008 Textbook Guide. This research characterizes the frequency of Astronomical contents appearing in the texts, in the pictures, and in the hands-on activities. Additionally, it describes some misconceptions and presents additional information on the collections. La importancia de los libros de texto en las aulas se pone de manifiesto cuando los estudios indican que este recurso educativo es a menudo la única fuente de consulta utilizada por el profesor de ciencias de la escuela primaria para preparar sus lecciones. Cuando analizamos el contenido presente en los libros de texto de astronomía aprobados por el Programa Nacional de Libros de Texto de 2008 y que, en teoría, son los mejores libros disponibles en el mercado editorial brasileño, buscamos examinar algunas categorías que figuran en los libros de texto de la Guía de Libros Didácticos de 2008. El estudio caracteriza la frecuencia del contenido de Astronomía en el texto, en las figuras, y en las actividades de experimentación. También describe algunos errores conceptuales y presenta un conjunto de información adicional sobre las colecciones. A importância dos livros didáticos nas salas de aula revela-se quando estudos apontam que este recurso pedagógico é, muitas vezes, a única fonte de consulta utilizada pelo professor de Ciências do ensino fundamental para a preparação de suas aulas. Quando analisamos os conteúdos de Astronomia presentes nos livros didáticos aprovados no Programa Nacional do Livro Didático de 2008 e que, teoricamente, são os

  14. Evolution of the Astronomy Concepts Along Basic Education Cycle. (Breton Title: Evolução dos Conceitos de Astronomia no Decorrer da Educação Básica.) La Evolución de los Conceptos de Astronomía Durante la Educación Básica

    NASA Astrophysics Data System (ADS)

    Darroz, Luiz Marcelo; da Rosa, Cleci Werner; Becker da Rosa, Álvaro; Samudio Pèrez, Carlos Ariel

    2014-07-01

    learning of astronomy in basic education. Embora a astronomia seja considerada uma das ciências mais antigas da humanidade e ainda que a compreensão de seus conceitos tenha trazido enormes avanços para a Ciência e, consequentemente, para a sociedade, observa-se que uma parcela significativa de pessoas encontra-se à margem desses conhecimentos. De acordo com os Parâmetros Curriculares Nacionais para a Educação Básica, cabe à escola a difusão dos conceitos cientificamente corretos, entre eles os relacionados à área de astronomia. Pertinente a essa questão, apresenta-se uma pesquisa realizada com 140 estudantes do nono ano do ensino fundamental e com 120 estudantes da terceira série do ensino médio de quatro escolas da região de Passo Fundo/RS. Buscou-se averiguar, por meio de um questionário composto de questões abertas e de múltipla escolha, o conhecimento desse grupo de estudantes acerca de termos e fenômenos astronômicos básicos e, também, verificar se o índice de acertos cresce à medida que eles avançam nas diferentes e gradativas séries dos ensinos fundamental e médio. De modo geral, os resultados apresentados demonstram que o ensino de astronomia na educação básica enfrenta deficiências. Das 20 questões investigadas, em 17 os índices de acertos são semelhantes nas respostas dadas por estudantes de nível fundamental e médio, revelando que muitas concepções equivocadas permanecem ao longo da educação básica. Isso evidencia que tais temas não são - ou são pouco - abordados durante esses dois níveis de escolarização. Assim, conclui-se que a discussão dos conceitos relacionados com a astronomia deve receber maior ênfase na abordagem dos diferentes conteúdos, sendo necessária uma ação nacional em prol do seu ensino. Acredita-se que essa ação nacional deve estar apoiada em um pilar triplo de atores coletivos: comunidade científica, comunidade astronômica semiprofissional e comunidade escolar. Por fim, esse pilar seria

  15. Difficulties of First Years Elementary School Teachers with the Teaching of Astronomy. (Breton Title: Dificuldades de Professores dos Anos Iniciais do Ensino Fundamental em Relação ao Ensino da Astronomia. ) Dificultades de LOS Profesores de los Primeros Años de la Escuela Primaria en Relación a la Enseñanza de la Astronomía

    NASA Astrophysics Data System (ADS)

    Langhi, Rodolfo; Nardi, Roberto

    2005-12-01

    This paper reports Primary School teachers' discourses analysis about their difficulties related to the teaching of Astronomy. It reports partial data of a master's level research carried out in the last two years, named "An exploratory study for inserting Astronomy in primary school teachers' education" (LANGHI, 2004). The study took into consideration students' and teachers' common sense conceptions about astronomical phenomena, conceptual mistakes in textbooks, and Astronomy's suggestions given by the PCN (Parâmetros Curriculares Nacionais - The Brazilian National Curriculum Standards). The paper aims to characterize teachers' difficulties, in order to provide subsides to the implementation of an initial or continuing education program. This study is justified by the fact that courses plans like these only will be adapted to the teacher's (and students') reality, if there is a primary investigation about what the teachers really need to know about Astronomy. This fact was possible here by the enunciations interpretation of a teachers' sample using semi-structured interviews, according to discourse analysis procedures. The research outcomes show difficulties related to factors like: those of personal order, methodological, on teacher's formation, educational infrastructure and other related to information sources for educators. Este artigo, que relata as dificuldades de professores em relação ao ensino da Astronomia, faz parte de um estudo exploratório para a inserção da Astronomia na formação de professores dos anos iniciais do Ensino Fundamental. Esse estudo leva em consideração as concepções alternativas de alunos e professores sobre fenômenos astronômicos, os erros conceituais em livros didáticos e as sugestões de conteúdos de Astronomia constantes nos PCN (Parâmetros Curriculares Nacionais). Caracterizar as dificuldades dos professores é a questão central deste texto, apontando para o objetivo de contribuir com subsídios para um futuro

  16. Difficulties of First Years Elementary School Teachers with the Teaching of Astronomy. (Breton Title: Dificuldades de Professores dos Anos Iniciais do Ensino Fundamental em Relação ao Ensino da Astronomia. ) Dificultades de LOS Profesores de los Primeros Años de la Escuela Primaria en Relación a la Enseñanza de la Astronomía

    NASA Astrophysics Data System (ADS)

    Langhi, Rodolfo; Nardi, Roberto

    2005-12-01

    This paper reports Primary School teachers' discourses analysis about their difficulties related to the teaching of Astronomy. It reports partial data of a master's level research carried out in the last two years, named "An exploratory study for inserting Astronomy in primary school teachers' education" (LANGHI, 2004). The study took into consideration students' and teachers' common sense conceptions about astronomical phenomena, conceptual mistakes in textbooks, and Astronomy's suggestions given by the PCN (Parâmetros Curriculares Nacionais - The Brazilian National Curriculum Standards). The paper aims to characterize teachers' difficulties, in order to provide subsides to the implementation of an initial or continuing education program. This study is justified by the fact that courses plans like these only will be adapted to the teacher's (and students') reality, if there is a primary investigation about what the teachers really need to know about Astronomy. This fact was possible here by the enunciations interpretation of a teachers' sample using semi-structured interviews, according to discourse analysis procedures. The research outcomes show difficulties related to factors like: those of personal order, methodological, on teacher's formation, educational infrastructure and other related to information sources for educators. Este artigo, que relata as dificuldades de professores em relação ao ensino da Astronomia, faz parte de um estudo exploratório para a inserção da Astronomia na formação de professores dos anos iniciais do Ensino Fundamental. Esse estudo leva em consideração as concepções alternativas de alunos e professores sobre fenômenos astronômicos, os erros conceituais em livros didáticos e as sugestões de conteúdos de Astronomia constantes nos PCN (Parâmetros Curriculares Nacionais). Caracterizar as dificuldades dos professores é a questão central deste texto, apontando para o objetivo de contribuir com subsídios para um futuro

  17. The Astronomy Club of Araranguá: Educating Science Teachers as Science Communicators. (Breton Title: Clube de Astronomia de AraranguÁ: a Formação de Professores de Ciências Como Divulgadores Científicos. ) Club de Astronomía de Araranguá: la Formación del Profesorado Como Comunicadores de la Ciencia

    NASA Astrophysics Data System (ADS)

    Damasio, Felipe; Allain, Olivier; Antunes Rodrigues, Adriano

    2013-07-01

    The study reported in this work takes place since 2009 at the Federal Institute of Education, Science and Technology of Santa Catarina, Campus Araranguá. Our main goal is to help form teachers, training undergraduate students in Natural Sciences with specialization in Physics as science communicators, as well as to promote actions of broader scientific popularization in the region of the town of Araranguá through an Astronomy Club called CA2. Among the actions of scientific popularization that the students promote are: video production, radio broadcasts, lectures, nightly observations, preparation and exhibition of posters, physics teaching for children, continuing education activities for teachers and regular physics teaching using Astronomy as a theme. The Club's teacher education and scientific dissemination work is based on the Theory of Meaningful Learning, always trying to reach the student's predisposition to learn and produce potentially meaningful material, the two essential conditions for meaningful learning to occur. O estudo que este trabalho relata ocorre desde 2009 no Instituto Federal de Educação, Ciência e Tecnologia de Santa Catarina, campus Araranguá. Nele procura-se formar divulgadores científicos durante a formação inicial de docentes do curso de Licenciatura em Ciências da Natureza com habilitação em Física, além de promover ações de divulgação científica para o público geral da região da cidade de Araranguá por meio de um Clube de Astronomia chamado CA² (Clube de Astronomia de Araranguá). Entre as ações de divulgação científica que os licenciandos promovem estão: produção de vídeos, programas de rádio, palestras, observações noturnas, confecção e exposição de pôsteres, ensino de física para crianças, formação continuada de professores em atividades e ensino de Física regular utilizando a Astronomia como tema gerador. O trabalho de formação docente e divulgação científica do Clube fundamenta

  18. On the Formation of a Study Group to the Realization of Workshops for Teachers: Astronomy in Basic Education in Umuarama-Pr (Spanish Title: De la Formación de un Grupo de Estudios a la Realización de los Talleres Para los Profesores: la Astronomía en la Educación Básica en Umuarama-Pr ) Da Formação de um Grupo de Estudos À Realização de Oficinas Para Professores: a Astronomia na Educação Básica em Umuarama-Pr

    NASA Astrophysics Data System (ADS)

    Belusso, Diane; Akira Sakai, Otávio

    2013-12-01

    In this article, we aimed to present the activities developed by the Astronomy Study Group (ASG) to contribute to the dissemination and improvement of the astronomy teaching-learning. The results of a research carried out in schools of Umuarama-PR are shown, with the intention of checking the students' knowledge and interest in relation to Astronomy. It is reported the realization of workshops for Science teachers linked to the Education Regional Nucleus. The research and the workshop execution promoted the direct contact of the study group with the community; the results were used to diagnose the state of astronomy teaching-learning, in the basic education in Umuarama-PR. En este artículo se intenta presentar las actividades desarrolladas por el Grupo de Estudios de Astronomía (GEA) y contribuir para la divulgación y mejoría de la enseñanza-aprendizaje de la Astronomía. Se presentan los resultados de una investigación realizada en las escuelas de Umuarama-PR, con la intención de determinar el grado de conocimiento y el interés de los estudiantes en relación a la astronomía. Se relata la realización de talleres de capacitación para los profesores de ciencias vinculados al Núcleo Regional del Educación. La ejecución de la investigación y de los talleres promovió el contacto directo del grupo de estudios con la comunidad; los resultados sirvieron de diagnóstico de la enseñanza aprendizaje de la astronomía en la educación básica en Umuarama-PR. Neste artigo, objetiva-se apresentar as atividades desenvolvidas pelo Grupo de Estudos de Astronomia (GEA) e contribuir para a divulgação e melhoria do ensino-aprendizagem de astronomia. São apresentados os resultados de uma pesquisa realizada nas escolas de Umuarama-PR, com o intuito de averiguar o conhecimento e o interesse dos estudantes em relação à astronomia. Relata-se a realização de oficinas de capacitação para professores de ciências vinculados ao Núcleo Regional de Educação. A

  19. Conversations with Marcgrave: the Origin of Modern Astronomy in the Southern Hemisphere (Spanish Title: Conversando con Marcgrave: El Origen de la Astronomía Moderna en el Hemisferio Sur) Conversando Com Marcgrave: a Origem da Moderna Astronomia no Hemisfério Sul

    NASA Astrophysics Data System (ADS)

    Medeiros, Alexandre; Araújo, Fábio

    2005-12-01

    primer observatorio astronómico del hemisferio y autor de las primeras observaciones astronómicas sistemáticas utilizando telescopios de este lado del mundo. Nuestra "conversación" con Marcgrave es imaginada en el marco del Recife antiguo, lugar donde él vivió durante el período de Mauricio de Nassau, y reune algunos colegas profesores apasionados por la enseñanza de la Astronomía. La historia es contada, de esta forma, dentro de un clima ameno y hasta un poco divertido, si bien las informaciones históricas y conceptuales contenidas en ella están basadas en fuentes bibliográficas confiables, debidamente referenciadas al final del texto. Estas fuentes van desde la obra original de este científico, en la cual aparece su relato sobre la observación de un eclipse solar en Recife, pasando por obras clásicas respecto de él mismo, como la del profesor Juliano Moreira, hasta fuentes mucho más recientes como el influyente trabajo del profesor John North. Otros textos importantes referidos al período de la colonización holandesa en el Brasil, tales como las obras clásicas de Charles Boxer, Bouman y Boogaart entre otros, son también utilizados en la construcción de esta dramatización pedagógica que se refiere a un interesante capítulo de la Historia de la Astronomía. O ano de 2004 assinala os 400 anos do nascimento do conde Maurício de Nassau, um importante personagem da história do Brasil. O presente texto está relacionado com o período do domínio holandês em Pernambuco. O artigo tenta resgatar o começo do estudo da Astronomia no hemisfério Sul. Para tal, idealizamos uma dramatização de uma entrevista fictícia com o astrônomo alemão Georg Marcgrave, construtor do primeiro observatório astronômico deste hemisfério e autor das primeiras observações astronômicas sistemáticas com o uso de telescópios neste lado do mundo. Nossa "conversa" com Marcgrave é idealizada no cenário do Recife antigo, local em que ele viveu no período de Maur

  20. Different Cultures in Astronomy Education and Their Meanings in the Classroom. (Spanish Title: Las Diferentes Culturas en la Educación en Astronomía y Sus Significados EN EL Aula. ) As Diferentes Culturas na Educação em Astronomia E Seus Significados em Sala de Aula

    NASA Astrophysics Data System (ADS)

    Pereira de Barros, Vicente; Bovolenta Ovigli, Daniel Fernando

    2014-12-01

    el trabajo con Astronomía(s) en la clase. Se observó que los participantes todavía no habían presentado estos temas en sus clases y tampoco habían participado en cursos de formación que abordaran estos temas. O presente trabalho apresenta uma reflexão acerca da utilização da História da Ciência no currículo da educação formal, por meio da discussão relativa ao emprego de elementos culturais de grupos étnicos em ações voltadas à educação em Astronomia. O trabalho foi desenvolvido no âmbito de um curso de extensão e a análise aqui empreendida refere-se a um encontro que abordou sequências didáticas relativas àquele tema, com fundamento na lei 11.645/2008 e a obrigatoriedade de abordagem da temática "História e Cultura Afro-Brasileira e Indígena" no currículo oficial. A ação de extensão ocorreu junto a professores que ensinam Ciências da Natureza, no interior do estado de São Paulo, discutindo-se temas relativos ao uso de História da Ciência e o relacionamento com cosmogonias oriundas dos povos Iorubá e Tupi, evidenciando como podem enriquecer o trabalho com a(s) Astronomia(s) em sala de aula. Observou-se que os participantes ainda não haviam apresentado estes temas em suas aulas e, igualmente, não participaram de cursos de formação que contemplassem a referida temática.

  1. Memories of Astronomy Education in Brazil: Clippings from the Discourses of Interviewed Researchers on the Subject. (Spanish Title: Memorias de la Educación en Astronomía en Brasil: Recortes de los Discursos de Investigadores Entrevistados Acerca del Tema ) Memórias da Educação em Astronomia no Brasil: Recortes a Partir das Falas de Pesquisadores Entrevistados sobre o Tema

    NASA Astrophysics Data System (ADS)

    Iachel, Gustavo; Nardi, Roberto

    2014-12-01

    This paper presents a historical retrospective concerning data from a research in Astronomy Education in Brazil, after 1973. It was organized on the basis of the speech analysis of national researchers considered references in this field by their peers. Furthermore, it was elaborated on the basis of other studies from the areas of Science Education, Physics and Astronomy. This historical overview was developed in order to facilitate understanding of the contexts in which the interviewed researchers have developed professionally. Moreover, we attempted to recover the memory of the growing field of research in Astronomy Education in the country. We believe that the history presented can help those trying to understand the past in an attempt to resolve current and future demands. Se presenta en este artículo una retrospectiva histórica referente a datos provenientes de la investigación en enseñanza de la astronomía en el Brasil, después de 1973, organizada sobre la base del análisis de los discursos de los investigadores nacionales considerados referencias en este campo, y también en la lectura de las publicaciones en las áreas de Enseñanza de las Ciencias, Física y Astronomía. Este repaso histórico se desarrolló con el fin de facilitar la comprensión de los contextos en los que los investigadores entrevistados se han desarrollado profesionalmente. Por otra parte, se intentó recuperar la memoria del creciente campo de la investigación en Educación en Astronomía en el país. Creemos que el relato presentado puede contribuir a quien trata de comprender el pasado, en un intento de resolver las demandas actuales y futuras. Relata-se neste artigo uma retrospectiva histórica referente a dados provenientes de pesquisa em Educação em Astronomia no país, pós 1973, organizada com base na análise das falas de pesquisadores considerados referências nacionais nesse campo, como também na leitura de publicações das áreas de ensino de Ciências, F

  2. The Universe in a Box: Introduction to the Study of Astronomy in the Initial Formation of Physics Teachers. (Spanish Title: El Universo Representado en Una Caja: Introducción al Estudio de la Astronomía en la Formación Inicial de Profesores de Física.) O Universo Representado em Uma Caixa: Introdução ao Estudo da Astronomia NA Formação Inicial de Professores de Física

    NASA Astrophysics Data System (ADS)

    Longhini, Marcos Daniel

    2009-07-01

    This is a report of an activity of introduction to the study of Astronomy developed with a group of future Physics teachers at a Brazilian public university. Such activity had the goal of giving privileged emphasis to notions of spatiality, alternative conceptions of the participants and the process of interaction among peers, and consisted of the representation, in a three dimensional space, of the models of the universe that the participants had. The results, which were categorized as miscellaneous, geocentric, heliocentric and acentric models of the universe, were qualitatively analyzed. Analyses of the activity in the perspective of the participants are indicated and additional considerations are made regarding its use as a resource for teaching Astronomy and for teacher training. Este es el informe de una actividad para presentar un estudio introductorio de la Astronomía, desarrollado con una clase de futuros profesores de física en una universidad pública brasileña. Esta actividad tuvo como objetivo centrar las nociones de espacialidad, las concepciones alternativas de los participantes y el proceso de interacción entre pares, y consistió en la representación en un espacio tridimensional, de los modelos del universo que los participantes habían. Los resultados, que se clasificaron en universo miscelania, geocéntrico, heliocéntrico y acentrico, se analizaron cualitativamente. Son identificadas análisis de la actividad por los participantes, e hizo observaciones sobre su uso como recurso para la enseñanza de la astronomía y la formación de docentes. Trata-se do relato de uma atividade de introdução ao estudo da Astronomia, desenvolvida com uma turma de futuros professores de Física, em uma universidade pública brasileira. Tal atividade teve como meta privilegiar noções de espacialidade, as concepções alternativas dos participantes e o processo de interação entre pares e constou da representação, em um espaço tridimensional, dos

  3. The Reflective Abstraction Theory and the History of Astronomy. (Spanish Title: La Teoría de la Abstracción Reflexionante y la Historia de la Astronomía.) A Teoria da Abstração Reflexionante e a História da Astronomia.

    NASA Astrophysics Data System (ADS)

    Chiesa Bartelmebs, Roberta; Batista Siqueira Harres, João; da Silva, João Alberto

    2014-12-01

    This work is presented as a theoretical essay on some facts from the history of astronomy analyzed according to the theory of reflective abstraction developed by Jean Piaget and collaborators (1970). Its aim is to understand the reasons that led to different astronomers, at the same historical period and culture, to "see" quite different evidences about the same phenomenon. In addition, we intend to facilitate the understanding of science as a human construction, subject to a time epoch and the ways of understanding of each scientist. Este trabajo se presenta como un ensayo teórico sobre algunos hechos históricos de la astronomía, analizados según la teoría de la abstracción reflexionante de Jean Piaget y sus colaboradores (1970). Se trata de comprender los motivos que llevaran a distintos astrónomos, de una misma época histórica y cultural, a "ver" diferentes evidencias sobre un mismo fenómeno. Además, se intenta posibilitar la comprensión de la ciencia como construcción humana, la cual es condicionada por su momento histórico y por las creencias y las formas de entender de los científicos. Este trabalho configura-se como um ensaio teórico a respeito de alguns fatos da história da astronomia analisados segundo a teoria da abstração reflexionante elaborada por Jean Piaget e seus colaboradores (1970). Trata-se de compreender os motivos que levaram diferentes astrônomos, da mesma época histórica e cultural, a "enxergarem" evidências tão diferentes sobre um mesmo fenômeno. Além disso, pretendemos possibilitar a compreensão das Ciências como construção humana, condicionadas a uma época e às crenças e os modos de compreender de cada cientista.

  4. Discussions about the Nature of Science in a Course on the History of Astronomy. (Spanish Title: Discusiones sobre la Naturaleza de la Ciencia en un Curso sobre Historia de la Astronomía.) Discussões sobre a Natureza da Ciência em um Curso sobre a História da Astronomia

    NASA Astrophysics Data System (ADS)

    Pires de Andrade, Victória Flório; L'Astorina, Bruno

    2010-07-01

    comunidade acadêmica e mostramos como alguns episódios da história da astronomia podem levar a discussões envolvendo alguns dos aspectos da natureza da ciência.

  5. Development of Educational Resources to Include the Teaching of Astronomy in the First Years of the Basic Education. (Spanish Title: Desarrollo de Recursos Pedagógicos Para Incluir la Enseñanza de la Astronomía en los Primeros Años de la Educación Básica.) Desenvolvimento de Recursos Pedagógicos Para Inserir o Ensino de Astronomia nas Séries Iniciais do Ensino Fundamental

    NASA Astrophysics Data System (ADS)

    da Silva Morett, Samara; de Oliveira Souza, Marcelo

    2010-07-01

    ía y la vida cotidiana de los estudiantes. La inclusión de la astronomía en la escuela primaria es una manera de demostrar a los estudiantes cómo este campo está presente de forma activa en su vida cotidiana. Las clases que participan en el proyecto participaron en un estudio con el objetivo de proporcionar información a los conocimientos previos que tenían sobre los temas de la astronomía que se examinaron durante el proyecto. Con los experimentos realizados, y la ayuda de las nuevas tecnologías, conceptos astronómicos fueron presentados a los estudiantes de 4to y 5to año de la educación básica de una escuela municipal de Campos dos Goytacazes (RJ). Después de las presentaciones nuevos datos fueran colectados y se han llevado a cabo con el fin de verificar el nivel de aprendizaje alcanzado y se observó que el método utilizado fue una herramienta importante para ayudar al proceso de enseñanza y aprendizaje. El proyecto logró resultados satisfactorios. Neste trabalho será apresentado o desenvolvimento de recursos pedagógicos para a apresentação de conceitos de astronomia nas séries iniciais do ensino fundamental. Este material é composto por apresentações realizadas com o uso de novos recursos tecnológicos, pela fabricação de experimentos e a discussão de curiosidades relativas a esta área de conhecimento. Os experimentos foram construídos com material de baixo custo com o objetivo de permitir que os alunos envolvidos pudessem refazê-los em outras ocasiões. O material apresentado busca enfatizar a relação entre a astronomia e o cotidiano dos alunos. A inclusão da astronomia no ensino fundamental e uma forma de demonstrar aoestudante como esta área está presente de forma ativa em seu cotidiano. As turmas envolvidas no projeto participaram de uma pesquisa com o objetivo de obter dados relativos ao conhecimento prévio que possuíam sobre os tópicos de astronomia que foram considerados no decorrer do projeto. Com os experimentos

  6. Development of Educational Resources to Include the Teaching of Astronomy in the First Years of the Basic Education. (Spanish Title: Desarrollo de Recursos Pedagógicos Para Incluir la Enseñanza de la Astronomía en los Primeros Años de la Educación Básica.) Desenvolvimento de Recursos Pedagógicos Para Inserir o Ensino de Astronomia nas Séries Iniciais do Ensino Fundamental

    NASA Astrophysics Data System (ADS)

    da Silva Morett, Samara; de Oliveira Souza, Marcelo

    2010-07-01

    ía y la vida cotidiana de los estudiantes. La inclusión de la astronomía en la escuela primaria es una manera de demostrar a los estudiantes cómo este campo está presente de forma activa en su vida cotidiana. Las clases que participan en el proyecto participaron en un estudio con el objetivo de proporcionar información a los conocimientos previos que tenían sobre los temas de la astronomía que se examinaron durante el proyecto. Con los experimentos realizados, y la ayuda de las nuevas tecnologías, conceptos astronómicos fueron presentados a los estudiantes de 4to y 5to año de la educación básica de una escuela municipal de Campos dos Goytacazes (RJ). Después de las presentaciones nuevos datos fueran colectados y se han llevado a cabo con el fin de verificar el nivel de aprendizaje alcanzado y se observó que el método utilizado fue una herramienta importante para ayudar al proceso de enseñanza y aprendizaje. El proyecto logró resultados satisfactorios. Neste trabalho será apresentado o desenvolvimento de recursos pedagógicos para a apresentação de conceitos de astronomia nas séries iniciais do ensino fundamental. Este material é composto por apresentações realizadas com o uso de novos recursos tecnológicos, pela fabricação de experimentos e a discussão de curiosidades relativas a esta área de conhecimento. Os experimentos foram construídos com material de baixo custo com o objetivo de permitir que os alunos envolvidos pudessem refazê-los em outras ocasiões. O material apresentado busca enfatizar a relação entre a astronomia e o cotidiano dos alunos. A inclusão da astronomia no ensino fundamental e uma forma de demonstrar aoestudante como esta área está presente de forma ativa em seu cotidiano. As turmas envolvidas no projeto participaram de uma pesquisa com o objetivo de obter dados relativos ao conhecimento prévio que possuíam sobre os tópicos de astronomia que foram considerados no decorrer do projeto. Com os experimentos

  7. Teaching and Popularization of Astronomy in Latin America by the Liada Perspective. (Spanish Title: Enseñanza y Divulgación de la Astronomía en la América Latina en la Perspectiva de la Liada.) Ensino e Divulgação da Astronomia na América Latina na Perspectiva da Liada

    NASA Astrophysics Data System (ADS)

    Bretones, Paulo Sergio

    2008-12-01

    disponibilizados en la página de la Sección, faz-se una análisis y discusión sobre la importancia de tales relatos para finalidades educacionales. Es presentada una Hoja de reporte elaborado como sugestión para presentación de relatos por parte de individuos y instituciones ben como discutida la importancia de la sistematización de experiencias visando mayor visibilidad y cambio de informaciones en el área. Concluí con una evaluación de los proyectos, su potencial y limitaciones, ben como sugestiones de proyectos futuros visando mayor interacción entre los países de la América Latina y tornando disponible la Sección para esta finalidad.

    Esse trabalho visa divulgar e analisar as atividades da Seção de Ensino e Divulgação de Astronomia (SEDA) da Liga Iberoamericana de Astronomia (LIADA). Após um histórico da LIADA, são apresentados os diversos projetos da Seção que conta com a colaboração de coordenadores locais na maioria dos países da América Latina. São apresentados os projetos que visam chamar a atenção do público em geral, estudantes e professores para a observação do céu e posterior envio de relatos para colocação na página da Seção na Internet. Mais especificamente são analisados os projetos e relatos relacionados aos eclipses ocorridos desde o ano 2000. Utilizando-se os arquivos disponibilizados na página da Seção, faz-se uma análise e discussão sobre a importância de tais relatos para finalidades educacionais. É apresentado um formulário elaborado como sugestão para apresentação de relatos por parte de indivíduos e instituições bem como discutida a importância da sistematização de experiências visando maior visibilidade e troca de informações na área. Conclui com uma avaliação dos projetos, seu potencial e limitações, bem como sugestões de projetos futuros visando maior interação entre os países da América Latina e tornando disponível a Seção para esta finalidade.

  8. Sky Observation with the Use of the Software Stellarium for Teaching Astronomy in Classes of Youth and Adult Education. (Spanish Title: Observación del Cielo con la Utilización del Software Stellarium en Las Clases de Educación de Jóvenes y Adultos.) Observação do Céu Aliada À Utilização do Software Stellarium no Ensino de Astronomia em Turmas de Educação de Jovens e Adultos (EJA)

    NASA Astrophysics Data System (ADS)

    Oliveira Bernardes, Adriana

    2010-12-01

    en las ciencias, o sea, elaborar y desarrollar un plan de alfabetización científica. Se describe en detalle este plan, las actividades realizadas y los resultados obtenidos hasta el presente. O objetivo do presente artigo é apresentar um projeto desenvolvido através de parceria entre o Clube de Astronomia de Itaocara Marcos Pontes (CAIMP) e o Colégio Estadual Jaime Queiroz de Souza, ambos localizados na cidade de Itaocara, no Noroeste Fluminense, no sentido de divulgar junto às turmas de EJA (Ensino de Jovens e Adultos) a disciplina Astronomia. Conhecendo o caráter interdisciplinar da Astronomia, desenvolvemos este trabalho para motivar o aprendizado de Ciências junto a alunos de EJA do Ensino Médio que cursam as disciplinas Química, Física e Biologia. Inicialmente, realizamos na escola pesquisa sobre o conhecimento prévio de Astronomia da turma de EJA, observando que é escasso o conhecimento de conceitos básicos do tema, muitos dos quais deveriam ser assimilados através do conteúdo da disciplina Física. Com esses dados, foi possível elaborar várias atividades que possibilitassem um maior envolvimento dos estudantes com a Ciência, realizando dentro da escola um trabalho de alfabetização científica, cujas atividades serão apresentadas neste artigo.

  9. Astronomy in High School: Using a Mini-Planetarium to Understand Details of the Apparent Movement of Stars. (Spanish Title: Astronomía en la Escuela Secundaria: Comprendiendo los Detalles del Movimiento Aparente de Las Estrellas con un Miniplanetario.) Astronomia no Ensino Médio: Compreendendo Detalhes do Movimento Aparente das Estrelas com um Miniplanetário

    NASA Astrophysics Data System (ADS)

    dos Santos Leão, Demetrius

    2013-07-01

    en la comprensión de estas cuestiones y demostraron un gran interés por esta metodología. O objetivo deste artigo é apresentar parte dos resultados obtidos com a intervenção feita como projeto da dissertação de mestrado do autor, que consistiu no desenvolvimento de um conjunto de aulas de Astronomia, com alunos do 1º Ano do Ensino Médio de uma escola da rede privada do Distrito Federal (Brasília, Brasil), empregando como recurso principal um material didático chamado miniplanetário (MP). Utilizando como pressuposto teórico norteador dessas aulas as ideias de contextualização e dialogicidade de Paulo Freire, foi proposta aos estudantes a montagem e utilização desse recurso em uma sessão de planetário. Durante o projeto, enfatizaram-se assuntos como a trajetória aparente das estrelas para o céu de Brasília, a localização dos pontos cardeais a partir da constelação do Cruzeiro do Sul, as cores das estrelas e as estrelas vistas de uma determinada localidade. Apurou-se que os alunos apresentaram melhoria na compreensão desses assuntos, bem como demonstraram expressiva empolgação com essa metodologia desenvolvida.

  10. Forms of Appropriation of Tools for the Astronomy Education in Continuous Training of Teachers. (Spanish Title: Formas de Apropriación de Herramientas Para la Enseñanza de la Astronomía en la Formación Docente Continua.) Formas de Apropriação de Instrumentos Para o Ensino de Astronomia na Formação Continuada de Professores

    NASA Astrophysics Data System (ADS)

    Marques Soares, Leonardo; Sousa Nascimento, Silvania

    2012-07-01

    siete relatos. O objetivo principal desse artigo é apresentar algumas reflexões sobre a maneira como um grupo de professores se apropriaram dos instrumentos do KIT PARA O ENSINO DE ASTRONOMIA (KITPEA). Os sujeitos dessa pesquisa participaram do curso de especialização em ensino de astronomia oferecido pelo Projeto de Formação Continuada (Foco) no Centro de Ensino de Ciências e Matemática (CECIMIG) da Faculdade de Educação da Universidade Federal de Minas Gerais (FaE/UFMG). Coletamos as informações por meio de um questionário e de uma entrevista, aplicados a esses professores. Estruturamos a análise dessas informações com a ajuda da Teoria da Atividade e da Teoria da Ação Mediada. Interpretamos as falas dos professores usando como dispositivo analítico os elementos constituintes do sistema de atividade e os conceitos de apropriação e domínio. Dentre os 11 sujeitos que participaram da pesquisa, foi possível identificar a apropriação dos instrumentos em 7 narrativas.

  11. VI Olimpíada Brasileira de Astronomia

    NASA Astrophysics Data System (ADS)

    Canalle, J. B. G.; Villas da Rocha, J. F.; de Medeiros, J. R.; Wuensche de Souza, C. A.; da Silva, A. R.; Dottori, H. A.; Maia, M. A. G.; Poppe, P. C. R.; Martins, R. V.

    2004-04-01

    In this work we show the results of the VI Brazilian Olympiad of Astronomy, which took place on 17/05/2003 in all primary or secondary schools that previously registered. 76.445 students distributed over 1.565 schools from all Brazilian States took part in this event. A team of 5 students was selected to represent Brazil at the IX International Olympiad of Astronomy (IX IAO) in 2004. We participated of the VIII IAO that occurred in Stockholm, Sweden in 2003. Two of our students were awarded the bronze medal and silver medal in that event.

  12. Astronomia solare e ottica con il foro stenopeico

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    The observation of the Sun with pinholes was started in Florence's Cathedral in 1475, and in Ulugh Beg observatory in Samarcand in 1424-29, well before the invention of the telescope, for measuring the solar position and the variation of the obliquity of the Earth's axis. Later, with Kepler, pinholes' telescopes were used to follow the solar spots when the telescopes made by Galileo were not available. The use of pinholes in positional solar astrometry continued successfully up to 1800 in some great Italian and French Churches. Nowadays by using pinholes it is possible to show the principles of positional astronomy and imaging to students with instruments very easy to be built at almost no cost. The concepts of focal length, best focus, angular resolution, atmospheric seeing and atmospheric transmittance can be verified with such simple devices. Such pinhole telescopes have been built by primary-school students at the Astronomical Observatory dedicated to the Pope astronomer Sylvester II, located in Bukowiec, Poland, which is at its third year of activity. The largest solar spots have been observed clearly with these instruments, demonstrating the principles discussed in this presentation. The light cast by one of this devices with 70 m of focal length and 1 cm of diameter has permitted to repeat the experiences on the diffraction of the light, made in 1648 by the Jesuits Riccioli and Grimaldi.

  13. Ensenanza de la Astronomia a Traves de Metodos no Tradicionales

    NASA Astrophysics Data System (ADS)

    Tignanelli, H. L.

    1990-11-01

    REUMEN: Se presentan los aspects pri nc ipales de a ense? anza de la astronor:. a para -; s. En esta cc .unicaci #n, 5 ha especial mfasis em Ia descripci':"n de las caracteristicas y las posibi lidades peda gicas de los no tradicionales de aprendiZaje. E' : In the following the principal aspects of teaching of astrono ..y for children) are oresented. In this paper, special emphasis has been given to desc rib the characteristics and pedagogical possibilities of the non traditional methods of learning. : TEACHING

  14. Consideracoes Historicas sobre o Ensino Profissionalizante no Brasil (Historical Considerations about Professional Education in Brazil).

    ERIC Educational Resources Information Center

    Barros, Marta Silene Ferreira

    2000-01-01

    Analyzes the paths taken in professional education in Brazil from the colonial period until the formation of the republic. Refers to specialists as well as specific laws for each period described in the study. (BT)

  15. Analysis of the Presence of Content about Astronomy in a Decade of the National High School Examination (1998-2008). (Spanish Title: Análisis de la Presencia de Contenidos de Astronomía em Uma Década del Examen Nacional de Enseñaza Secundária (1998-2008).) Análise da Presença de Conteúdos de Astronomia em Uma DÉcada do Exame Nacional do Ensino Médio (1998-2008)

    NASA Astrophysics Data System (ADS)

    Gomide, Hanny Angeles; Longhini, Marcos Daniel

    2011-07-01

    In this paper we analyzed the presence of contents of Astronomy in the National High School Examination (ENEM) in its first decade (1998-2008). We verified the number of questions addressing this topic that were present over the years, as well as the most recurrent subjects. We discussed the results from what is proposed by the official documents regarding the teaching of Astronomy in the Elementary and Secondary Education and we entertain future expectations about the presence of contents of this science in future official examinations. En este trabajo realizamos un análisis de la presencia de contenidos de Astronomía em las pruebas del Examen Nacional de Enseñanza Secundaria (ENEM) em su primera década de existência (1998-2008). Contabilizamos la cantidad de preguntas incluyendo este tema que estuvieron presentes en el transcurso de los años, así como los temas más recurrentes. Discutimos los resultados a partir de lo propuesto por los documentos oficiales en relación a la enseñanza de Astronomía en la Educación Básica y elaboramos algunos apuntes sobre futuras expectativas em relación a la presencia de contenidos de esta ciencia en examenes oficiales. No presente trabalho fizemos uma análise da presença de conteúdos de Astronomia nas provas do Exame Nacional do Ensino Médio (ENEM), em sua primeira década de existência (1998-2008). Verificamos a quantidade de questões envolvendo essa temática que estiveram presentes no decorrer dos anos, assim como os temas mais recorrentes. Discutimos os resultados a partir do que é proposto pelos documentos oficiais em relação ao ensino de Astronomia na Educação Básica e tecemos alguns apontamentos sobre a expectativa futura quanto à presença de conteúdos dessa ciência nesse exame oficial.

  16. Astronomy Teaching and Teachers Continuing Education: the Interdisciplinarity during a Total Lunar Eclipse. (Spanish Title: Enseñanza de la Astronomía y la Formación Continua de Profesores: la Interdisciplinariedad Durante un Eclipse Total de Luna.) Educação EM Astronomia E Formação Continuada de Professores: a Interdisciplinaridade Durante um Eclipse Lunar TOTAL

    NASA Astrophysics Data System (ADS)

    Langhi, Rodolfo

    2009-07-01

    This paper describes how 67 teachers from 23 cities, could awaken, in students, the scientific interest, using a natural astronomical phenomenon: a total lunar eclipse. Before and after of eclipse, meetings for continuing education were characterized by interdisciplinarity of astronomy and the importance of these observations. Working groups were formed by teachers and students, who organized the survey data, mobilizing the people in their cities. The results point ways about how to provide the scientific culture and the motivation to learn science in students, using approaches between the following communities: scientific, amateur and school. En este artículo se describe cómo 67 profesores de 23 ciudades, despertó el interés científico en los estudiantes mediante un fenómeno astronómico: un eclipse total de Luna. Antes y después del eclipse, reuniones para la formación continua se centraron en la interdisciplinariedad de la astronomía, y la importancia de las observaciones de este tipo de fenómeno. Profesores y estudiantes formaron grupos de trabajo para investigar datos durante el eclipse, con el participación de la comunidad en sus ciudades. Los resultados apuntan a las opciones que conducen a la cultura científica y la motivación para aprender la ciencia, utilizando las relaciones de los siguientes grupos: científicos, aficionados y la escuela. Este texto relata como 67 professores, provenientes de 23 cidades, puderam despertar, nos alunos, o interesse científico utilizando um fenômeno natural astronômico: um eclipse lunar total. O evento foi precedido e procedido por encontros de formação continuada, onde se caracterizou a interdisciplinaridade da astronomia e a importância das observações de fenômenos como estes. Grupos de trabalho foram formados por professores e alunos, que se organizaram para o levantamento conjunto de dados durante o fenômeno, além do envolvimento da comunidade em suas respectivas cidades. Os resultados apontam

  17. BOOK REVIEW: Tycho Brahe and Prague: Crossroads of European Science

    NASA Astrophysics Data System (ADS)

    Sterken, C.; Christianson, J. R.; Hadravová, A.; Hadrava, P.; Solc, M.

    2003-01-01

    The 16th volume of the Acta Historica Astronomiae is the Proceedings of the International Symposium on the History of Science in the Rudolphine Period. The meeting was held in Prague from 22 to 25 October 2001, on the 400th anniversary of Tycho's sudden death, and was attended by approximately 65 scientists and historians. The volume contains 36 contributions dealing with the life and work of Tycho Brahe, the astronomy of the era, and many cultural aspects of Rudolphine Prague. One of the first papers is an eye-opener on the fact that Tycho Brahe was a cosmologically-driven observer. This is followed by a very illuminating paper on gender roles in science in the late 16th century, with emphasis on the role of Sophie Brahe, Tycho's youngest sister. Several subsequent papers reveal the existence of barely known links between Tycho and his contemporaneous colleagues. These extremely-well documented papers also deal with the broader philosophical investigation he was involved in, viz. meteorology, medicine, astrology, alchemy and even theology. Important names of Tycho's days are Petrus Severinus, Johannes Pratensis, Theophrastus Paracelsus, John Craig, Ursus (Nicolai Reymers Baer) etc. Very illuminating is the information on the relations between Tycho and the Jesuits in Prague, explaining the reason why this order was very supportive of the Tychonic cosmological model. The relationsship with Kepler, and also Kepler's observational activities (after Tycho's death) are highlighted as well as the hideous mode of communication between Galileo and Kepler. More than one paper deals with the accuracy and precision of Tycho's observations, and the causal impact of this accuracy on the scientific revolution. Another study discusses the study of Tycho's handwriting, this paper brings the aditional bonus of a list of accessible works which contain notes by him. One very interesting project was Brahe's proposal to the Republic of Venice to determine the exact latitudes of

  18. Perspectiva Historica de la Educacion Bilingue en los Estados Unidos (A Historical Perspective of Bilingual Education in the United States)

    ERIC Educational Resources Information Center

    Zamora, Juan Clemente

    1978-01-01

    This article defines bilingualism and bilingual education and traces the history of bilingual education in the United States, starting with the Spanish missions in the west. (Text is in Spanish.) (NCR)

  19. The International Standing Conference for the History of Education and "Paedagogica Historica": A Historical View on Institutional Strategies and Practices

    ERIC Educational Resources Information Center

    Fuchs, Eckhardt

    2014-01-01

    This article seeks to contribute to the institutional history of the discipline of history of education by examining the publication strategies and the associated institutional practices of the International Standing Conference for the History of Education, the international organisation representing those working in the field, and…

  20. Mixed-Methods Study that Examines Nine Science Teachers' Perceptions of Slooh Robotic Telescope for Teaching Astronomy. (Breton Title: Métodos Mistos de Estudo que Examinam a Percepção de Nove Professores de Ciências sobre o Telescópio Robótico Slooh Para Ensino de Astronomia.) Métodos Mixtos de Estudio que Examinan la Percepcion de Nueve Profesores de Ciencias sobre EL Telescopio Robótico Slooh Para la Enseñanza de la Astronomía

    NASA Astrophysics Data System (ADS)

    Gershun, Daniel C.; Slater, Timothy F.; Berryhill, Katie J.

    2014-07-01

    Although previous studies show that robotic telescopes have the potential to enhance student learning, there is comparatively little research that focuses on teacher perceptions of this technology. This study investigates: "what is the academic merit of using SLOOH robotic telescopes to teach astronomy as perceived by science teachers?" Our sample consists of nine science teachers of students aged 13-18 years. Pre- and post-tests, interviews, and surveys were collected during two weeks of a summer online course about robotic telescopes. While pre and post-tests do not reveal a statistically significant gain in astronomy content knowledge, analysis of qualitative data reveals five themes which describe the most important aspects of using SLOOH according to participants: "Images," "Interface," "Classroom Application," "Instructor Impact," and "Logistical Issues." Analysis of these themes suggests that SLOOH can provide an interactive and social learning environment with capabilities to incorporate crossdisciplinary themes. Embora estudos anteriores mostram que os telescópios robóticos têm o potencial de melhorar a aprendizagem dos alunos, há relativamente pouca investigação focada nas percepções de professores a respeito desta tecnologia. Este estudo investiga: "qual é o mérito acadêmico da utilização de telescópios robóticos Slooh para ensinar astronomia, tal como percebido pelos professores de ciências?" Nossa amostra é composta por nove professores de ciências de estudantes com idades entre 13-18 anos pré e pós-testes, entrevistas, e levantamentos foram coletados durante duas semanas de um curso on-line de verão sobre telescópios robóticos. Enquanto os testes pré e pós não revelaram um ganho estatisticamente significativo no conhecimento do conteúdo astronomia, a análise de dados qualitativos revela cinco temas que descrevem os aspectos mais importantes da utilização Slooh de acordo aos participantes: "Imagens", "Interface", "Aplica

  1. Establishing the Empirical Relationship Between Non-Science Majoring Undergraduate Learners' Spatial Thinking Skills and Their Conceptual Astronomy Knowledge. (Spanish Title: Estableciendo Una Relación Empírica Entre el Razonamiento Espacial de los Estudiantes de Graduación de Carreras no Científicas y su Conocimento Conceptual de la Astronomía.) Estabelecendo Uma Relação Empírica Entre o RacioCínio Espacial dos Estudantes de Graduação EM Carreiras Não Científicas e Seu Conhecimento Conceitual da Astronomia

    NASA Astrophysics Data System (ADS)

    Heyer, Inge; Slater, Stephanie J.; Slater, Timothy F.

    2013-12-01

    normalizadas, en el desempeño de los estudiantes en estos dos asuntos foram pequenas, 0.26 e 0.13 respectivamente. El razonamiento espacial de los estudiantes fue medido utilizando un instrumento específico desarrollado para este trabaljo. Las correlaciones entre los resultados de los tests astronómicos y este instrumento específico, antes y después del curso mostraron una relación entre moderada y fuerte, sugiriendo que la relación entre el razonamiento espacial y el conocimiento astronómico puede explicar hasta un 25% de la variación em el desempeño de los estudiantes. A comunidade da educação em astronomia tem suposto de forma implícita que o aprendizado da astronomia consiste em um domínio conceitual fundamentado no raciocínio espacial. Como um primeiro passo para identificar formalmente uma relação empírica entre estas duas coisas, utilizamos como amostra os estudantes de graduação de carreiras não científicas de um curso exploratório em uma universidade norte-americana do meio-oeste de médio porte com programa de Doutorado em andamento, onde estes estudantes foram submetidos a um diagnóstico de raciocino espacial e conceitos astronômicos antes e depois do mesmo. As ferramentas utilizadas foram o Test Of Astronomy Standards (TOAST) e o questionário What do you know? Utilizando somente dados completamente consistentes para esta análise, nossa amostra consistiu de 86 estudantes de graduação. As melhoras, depois de normalizadas, do desempenho dos estudantes nos dois quesitos foram pequenas, 0.26 e 0.13 respectivamente. O raciocínio espacial dos estudantes foi medido utilizando um instrumento específico desenhado para este trabalho. As correlações entre os resultados dos testes astronômicos e este instrumento específico antes e depois do curso mostraram uma relação entre moderada e forte, sugerindo que a relação entre o raciocínio espacial e o conhecimento astronômico pode explicar até um 25% na variação no desempenho dos

  2. Past, Present and Future: Forty Years of Revista Mexicana de Astronomia y Astrofisica

    NASA Astrophysics Data System (ADS)

    Allen, Christine; Torres-Peimbert, Silvia

    2015-08-01

    We cast a retrospective view on 40 years of publishing the Revista Mexicana de Astronomía y Astrofísica, founded in 1974. The journal is peer-reviewed, has appeared regularly since its foundation, and continues to attract original research papers, mostly by Mexican and Latin American authors. We share some musings about the future of our journal, in view of recent developments in the scientific publishing field.

  3. "Zhizneopisanie" astronomia N. N. Pavlova, im samim napisannoe %t Astronomer N. N. Pavlov's autobiography

    NASA Astrophysics Data System (ADS)

    Zhukov, V. Yu.

    This document called by the author "the life story" is written for the human resources department. It is a document intended for the official departmental purposes. At the same time there is something facinating about this documentary testimony about the epoch and the man. This short autobiography describes the early years of the Pulkovo astronomer N. N. Pavlov that fell on hard times of the Civil War. In the years between the World War I and the World War II he was awarded Mendeleyev Prize. He defended his doctorate dissertation after the evacuation from Leningrad. He was one fo the first Pulkovo astronomers to return to Leningrad in order to start reconstruction of the observatory that had been completely ruined during the war. Astronomer N. N. Pavlov renewed the Time Service in the city. N. N. Pavlov was a successful scientist and an outstanding person, all his life was devoted to science.

  4. Análise dos Resultados da VII Olimpíada Brasileira de Astronomia

    NASA Astrophysics Data System (ADS)

    Garcia Canalle, João Batista; Villas da Rocha, Jaime Fernando; Wuensche de Souza, Carlos Alexandre; Aguilera, Nuricel Villalonga; Preta Padilha, Maria De Fátima Catta; de Medeiros, José Renan; Dantas, Márcia Pragano; Roque da Silva, Adriana; Martins, Roberto Vieira; Dottori, Horácio Alberto; Maia, Márcio Antonio Geimba; Da Rocha Poppe, Paulo César; Rodrigues da Costa, Antônio Carlos

    2006-06-01

    In this work we show the results of the VII Brazilian Astronomy Olympiad (VII OBA), that occurred on 15/05/2004, in all previous registered elementary and high schools, public and/or private, urban and/or rural. Took part in this Olympiad 123.001 students (60,7 % more than VI OBA), distributed over 2.721 schools (increasing of 73% if compared with the VI OBA), belonging to all Brazilian states. The public schools are 75,5% and the private are 24,5%. The team of 4 students selected in the VI OBA (2003) represented the Brazil in the IX International Astronomy Olympiad (IX IAO), that occurred on October of 2004, in Ukraine and won a silver medal and two bronze medals.

  5. Problemi e di Fisica e Astronomia ed il metodo di Gerberto docente

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2015-04-01

    Teaching Physics and Astronomy to pupils of 14-19 years old requires nowadays a continuous upgrade of knowledge as well as a capacity of selecting topics. The art of presenting arguments made Gerbert the teacher Rogatus a Pluribus in the end of X century and it is still actual; the proposed series of problems wants to link everyday experiences with the mathematical models of the phenomena, to allow the prediction and explanation of the experimental data. These problems of Physics and Astronomy are “observation oriented”, as the method of Gerbert was to start from the experience to get the theory, and not viceversa. Physics is much more than an “applied Algebra”. In the dispute of Ravenna (980) between Gerbert and Otric from Magdeburg, the primacy of Physics with respect to Mathematics was discussed. In the Italian secondary technical schools there are laboratory activities, while there is nothing similar for Lyceums and for the Astronomy teaching which is limited to a series of notions to be learned without any kind of observation; considered too difficult in polluted skyes.

  6. GERBERTVS una nuova rivista per l'astronomia e la scienza nell'alto medioevo

    NASA Astrophysics Data System (ADS)

    Sigismondi, C.

    GERBERTVS appears as an international e-journal on medieval science, namely astronomy. It has been created to gather all the studia promoted on Gerbert of Aurillac, the most prominent figure of the tenth century: astronomer, organ builder and music theoretician, mathematician, philosopher, and finally pope with the name of Silvester II (999-1003). Here is presented the first volume (2010) published in the institutional web site www.icra.it/gerbertus with the ISSN 2038-355X.

  7. Proceedings of the second international symposium on molecular markers in horticulture Acta Horticulturae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The second International Symposium on Molecular Markers in Horticulture was held at the CH2M Hill Alumni Center at Oregon State University (OSU), Corvallis (Oregon, US), from July 29 to August 1st, 2009. This symposium was convened by a scientist at the National Clonal Germplasm Repository (NCGR) of...

  8. El Universo a Sus Pies: Actividades y Recursos para Astronomia (Universe at Your Fingertips: An Astronomy Activity and Resource Notebook).

    ERIC Educational Resources Information Center

    Fraknoi, Andrew, Ed.; Schatz, Dennis, Ed.

    The goal of this resource notebook is to provide activities selected by astronomers and classroom teachers, comprehensive resource lists and bibliographies, background material on astronomical topics, and teaching ideas from experienced astronomy educators. Activities are grouped into several major areas of study in astronomy including lunar…

  9. L'Astronomia del Venerdí Santo, l'eclissi di Luna e l'ora della Sindone

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2014-05-01

    Dating the crucifixion on friday 3 April 33, when, at sunset a partially eclipsed Moon rised allows to interprete the speech of Saint Peter (Acts 2:20=Joel 3:4) on the day of Pentecost as including an account of this eclipse, as fulfillment of the Scriptures. Few minutes later the apparition of a third star of medium magnitude stated the beginning of the sabbatical rest: before that time Jesus has been buried, wrapped into the shroud. The observations of the equinoctial moonrise from the Mount of Olives on September 2013 are strongly in favour of the hypotehsis of possible observation of the lunar eclipse of 33 AD by Jewish people, as well as the sunrises observed from the Temple Institute terrace in Southern-East Jerusalem demonstrated that this eclipse could have been seen from Jerusalem. The depression of the horizon and the refraction allow to see Sun and Moon more than 1 degree below the geometrical horizon in the azimuthal direction ranging from 90 to 116, prologing to 16 minutes the duration of the partial lunar eclipse observed in 33AD. Texts of Matthew, Mark and Cyrillus of Jerusalem are also commented.

  10. Raízes pós-mitológicas da Astronomia Clássica

    NASA Astrophysics Data System (ADS)

    di Bartolo, L.; Villas da Rocha, J. F.

    2004-02-01

    Apresentamos como a invenção de um modelo astronômico e cosmológico fundado em causas naturais foi um processo gestado num ambiente cultural específico, o do advento do pensamento pós-mitológico, que tem como sua raiz mais funda a trajetória particular da Grécia Antiga, com ênfase na resolução de uma grave crise social e a evolução do mundo clássico para o contexto espiritual de um império universal.

  11. Comment on "Apatite: A new redox proxy for silicic magmas?" [Geochimica et Cosmochimica Acta 132 (2014) 101-119

    NASA Astrophysics Data System (ADS)

    Marks, Michael A. W.; Scharrer, Manuel; Ladenburger, Sara; Markl, Gregor

    2016-06-01

    Recently Miles et al. (2014) proposed that a negative correlation between oxygen fugacity (expressed as logfO2 and the Mn content of apatite from a range of intermediate to silicic igneous rocks could be used as an oxybarometer (Eq. (1)).

  12. Towards Understanding Leadership in Early Childhood Context: Cross-Cultural Perspectives. Acta Universitatis Ouluensis, E Scientique Rerum Socialium 35.

    ERIC Educational Resources Information Center

    Hujala, Eeva, Ed.; Puroila, Anna-Maija, Ed.

    Recognizing the importance of leadership in determining the quality of early care and education programs, the International Leadership Project (ILP) was initiated in 1996 to develop an understanding of cross-cultural perspectives on leadership, to develop a conceptual framework of leadership, and to develop cross-cultural methodologies for…

  13. Science convention "Rijeka and its Citizens in Medical History" 2000-2009 - history of medicine as a component of scientific visibility.

    PubMed

    Eterovic, Igor

    2011-01-01

    This paper analyses the form and content of the first ten science conventions "Rijeka and its Citizens in Medical History" ("Rijeka i Riječani u medicinskoj povjesnici") which were held in the period between 2000 and 2009 according to the archive data of the convention organizers Croatian Scientific Society for the History of Health Culture. It presents data on the inception of the idea of a science convention, its organisational features (organising committees, presiding committees, convention topics, venue, patrons) and number of participants. A total of 174 presentations whose abstracts were published in individual Convention Collections were given at the ten conventions by 103 different authors from Croatia and neighbouring countries. After the first ten years the entire material was compiled and published with an analytical comment in the anniversary issue Znanstveni skup Rijeka i Riječani u medicinskoj povjesnici 2000-2009 (Scientific Convention Rijeka and its Citizens in Medical History 2000-2009) within Biblioteka AMHA. Most of the papers printed in extenso are published in the magazine AMHA - Acta medico historica Adriatica. The analysis of all presentations provides quantity data on the number of presented papers, number of presenters and number of co-authored papers, as well as quality determinants within the evaluation of the achievement of science convention objectives. The end gives a review of the significance of this convention within the regional, national and international aspect. PMID:22047478

  14. Reply to "Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion", E. Storms, Thermochim. Acta (2005)

    SciTech Connect

    Shanahan, Kirk

    2005-09-21

    Dr. E. Storms has published a Letter [1] in which he argues that in a sequence of recent papers [2-5], the apparent excess heat signal claimed by Dr. Shanahan to arise from a calibration constant shift is actually true excess heat. In particular he proposes that the mechanisms proposed that foster the proposed calibration constant shifts [3,5] cannot occur as postulated for several reasons. As well, he proposes Shanahan has ignored the extant data proving this. Because this Letter may lend unwarranted support to acceptance of cold fusion claims, these erroneous arguments used by Storms need to be answered.

  15. Corrigendum to "Occurrence and abundance of 6-methyl branched glycerol dialkyl glycerol tetraethers in soils: Implications for palaeoclimate reconstruction" [Geochim. Cosmochim. Acta 141 (2014) 97-112

    NASA Astrophysics Data System (ADS)

    De Jonge, Cindy; Hopmans, Ellen C.; Zell, Claudia I.; Kim, Jung-Hyun; Schouten, Stefan; Sinninghe Damsté, Jaap S.

    2016-06-01

    The authors regret that the r2 values (squared pearson correlation coefficient values) reported in Figs. 7 and 8 and in the text, are instead the non-squared r values. This has no direct influence on our interpretation. We have included the corrected Figs. 7 and 8. The text describing these results should read as follows:

  16. Reply to comment by Marks et al. (2016) on "Apatite: A new redox proxy for silicic magmas?" [Geochimica et Cosmochimica Acta 132 (2014) 101-119

    NASA Astrophysics Data System (ADS)

    Miles, Andrew; Graham, Colin; Hawkesworth, Chris; Gillespie, Martin; Hinton, Richard; Bromiley, Geoffrey

    2016-06-01

    Marks et al. (2016) investigate the applicability of the Mn-in-apatite oxybarometer proposed by Miles et al. (2014) across a range of magma compositions using published data on well-characterised samples. The authors show that for magma compositions outside of the calc-alkaline and intermediate to silicic range used in the preliminary calibration, fO2 values calculated from Mn-in-apatite vary significantly from independently constrained estimates. These data are used to reiterate our warnings that other controls that are additional to oxygen fugacity are likely to affect Mn partitioning into apatite in some rock types, and particularly so in magmas that lie outside of the range of compositions and conditions used in the calibration. Marks et al. (2016) highlight that temperature may have an especially important effect on Mn partitioning in apatite in some rock types.

  17. Simposio sobre Educacion de Ninas: Evidencias, Temas, Acciones. Actas de sesiones. (Symposium on Girls Education: Evidence, Issues, Actions. Proceedings). (Washington, DC, May 17-18, 2000).

    ERIC Educational Resources Information Center

    Agency for International Development (IDCA), Washington, DC.

    This symposium highlighted core issues of controversy in girls' education and developed implications for policy and practice. Its evidence-based discussion forum encouraged dialogue, debate, and increased interaction and developed partnerships among academic institutions, nongovernmental organizations, multilateral development agencies, and other…

  18. A Diagnostic Assessment for the Teaching of Astronomy. (Spanish Title: Una Evaluación Diagnóstica Para la Enseñanza de la Astronomia.) Uma Avaliação Diagnóstica Para o Ensino da Astronomia

    NASA Astrophysics Data System (ADS)

    Pacifico Ribeiro de Assis Silveira, Felipa; Soares Gomes de Sousa, Célia Maria; Moreira, Antonio

    2011-07-01

    This article aims to present the results of a diagnostic evaluation, used as a tool for collecting data on prior knowledge of scientific concepts needed to understand the topic "Earth and Universe", from a group comprised of 47 students of 6th grade. The educational method of diagnosing the student's prior knowledge before teaching them is founded on the Meaningful Learning theory, proposed by David Ausubel. The diagnostic evaluation consisted of 25 questions; the answers were analyzed and categorized, making possible their interpretation, which allows us to understand the meanings assigned by the student to these concepts. It follows from the diagnostic evaluation, that the majority of students surveyed had difficulties in exposing scientific concepts on the topic "Earth and Universe" when starting the 6th grade. However, we identified relevant ideas and representations that contributed to the re-signification of scientific concepts proposed for the teaching of the subject in this grade. The results of diagnostic evaluation served as reference to the organization of the syllabus, making possible the learning process by matching the sequence of teaching to the students" characteristics and context of the classroom. It is expected that other researchers in this topic can also use the instrument presented in this paper. Este artículo tiene como objetivo presentar los resultados de una evaluación diagnóstica, utilizada como una herramienta para recoger datos sobre el conocimiento previo de los conceptos científicos necesarios para comprender el tema "Tierra y Universo", de un grupo compuesto por 47 alumnos de 6º grado de la escuela primaria. La acción pedagógica del diagnóstico de los conocimientos previos del estudiante antes de enseñarles está justificada por la teoría del Aprendizaje Significativo, propuesta por David Ausubel. La evaluación de diagnóstico consistió en 25 preguntas, las respuestas fueron analizadas y clasificadas objetivando-se su interpretación, lo que nos permite comprender los significados asignados por el estudiante a estos conceptos. Se desprende de la evaluación diagnóstica que la mayoría de los encuestados ha tenido dificultades para exponer los conceptos científicos sobre el Universo y la Tierra, para iniciar el 6 º grado. Sin embargo, se identificaron ideas relevantes y las representaciones que contribuyeron a la re-significación de los conceptos científicos propuestos para la enseñanza del tema en esta serie. Los resultados de la evaluación diagnóstica han servido como referencia para la organización del Programa, facilitando el proceso de aprendizaje, haciendo coincidir la secuencia didáctica a las características de los estudiantes y el contexto del aula. Se espera que el instrumento presentado en este documento también pueda ser utilizado por otros investigadores en investigaciones relacionadas con el tema. Este artigo tem como objetivo apresentar os resultados de uma avaliação diagnóstica, utilizada como instrumento para a coleta de dados sobre o conhecimento prévio de conceitos científicos, necessários à compreensão do tema Terra e Universo, de um grupo composto por 47 estudantes, da 6ª série do Ensino Fundamental. A ação pedagógica de diagnosticar os conhecimentos prévios, do estudante, antes de ensiná-los, tem fundamento na teoria da Aprendizagem Significativa, proposta por David Ausubel. Essa avaliação diagnóstica foi composta por 25 questões, cujas respostas foram analisadas e categorizadas visando sua interpretação, o que permitiu compreender os significados atribuídos pelo estudante a esses conceitos. Conclui-se, a partir da avaliação diagnóstica, que a maioria dos estudantes pesquisados apresentou dificuldades em expor conceitos científicos sobre o tema Terra e Universo ao iniciar a 6ª série. Entretanto, foram identificadas ideias e representações relevantes que contribuíram para a (re)significação dos conceitos científicos propostos para o ensino do tema nessa série. Os resultados da a

  19. A Diagnostic Assessment for the Teaching of Astronomy. (Spanish Title: Una Evaluación Diagnóstica Para la Enseñanza de la Astronomia.) Uma Avaliação Diagnóstica Para o Ensino da Astronomia

    NASA Astrophysics Data System (ADS)

    Pacifico Ribeiro de Assis Silveira, Felipa; Soares Gomes de Sousa, Célia Maria; Moreira, Antonio

    2011-07-01

    This article aims to present the results of a diagnostic evaluation, used as a tool for collecting data on prior knowledge of scientific concepts needed to understand the topic "Earth and Universe", from a group comprised of 47 students of 6th grade. The educational method of diagnosing the student's prior knowledge before teaching them is founded on the Meaningful Learning theory, proposed by David Ausubel. The diagnostic evaluation consisted of 25 questions; the answers were analyzed and categorized, making possible their interpretation, which allows us to understand the meanings assigned by the student to these concepts. It follows from the diagnostic evaluation, that the majority of students surveyed had difficulties in exposing scientific concepts on the topic "Earth and Universe" when starting the 6th grade. However, we identified relevant ideas and representations that contributed to the re-signification of scientific concepts proposed for the teaching of the subject in this grade. The results of diagnostic evaluation served as reference to the organization of the syllabus, making possible the learning process by matching the sequence of teaching to the students" characteristics and context of the classroom. It is expected that other researchers in this topic can also use the instrument presented in this paper. Este artículo tiene como objetivo presentar los resultados de una evaluación diagnóstica, utilizada como una herramienta para recoger datos sobre el conocimiento previo de los conceptos científicos necesarios para comprender el tema "Tierra y Universo", de un grupo compuesto por 47 alumnos de 6º grado de la escuela primaria. La acción pedagógica del diagnóstico de los conocimientos previos del estudiante antes de enseñarles está justificada por la teoría del Aprendizaje Significativo, propuesta por David Ausubel. La evaluación de diagnóstico consistió en 25 preguntas, las respuestas fueron analizadas y clasificadas objetivando-se su interpretación, lo que nos permite comprender los significados asignados por el estudiante a estos conceptos. Se desprende de la evaluación diagnóstica que la mayoría de los encuestados ha tenido dificultades para exponer los conceptos científicos sobre el Universo y la Tierra, para iniciar el 6 º grado. Sin embargo, se identificaron ideas relevantes y las representaciones que contribuyeron a la re-significación de los conceptos científicos propuestos para la enseñanza del tema en esta serie. Los resultados de la evaluación diagnóstica han servido como referencia para la organización del Programa, facilitando el proceso de aprendizaje, haciendo coincidir la secuencia didáctica a las características de los estudiantes y el contexto del aula. Se espera que el instrumento presentado en este documento también pueda ser utilizado por otros investigadores en investigaciones relacionadas con el tema. Este artigo tem como objetivo apresentar os resultados de uma avaliação diagnóstica, utilizada como instrumento para a coleta de dados sobre o conhecimento prévio de conceitos científicos, necessários à compreensão do tema Terra e Universo, de um grupo composto por 47 estudantes, da 6ª série do Ensino Fundamental. A ação pedagógica de diagnosticar os conhecimentos prévios, do estudante, antes de ensiná-los, tem fundamento na teoria da Aprendizagem Significativa, proposta por David Ausubel. Essa avaliação diagnóstica foi composta por 25 questões, cujas respostas foram analisadas e categorizadas visando sua interpretação, o que permitiu compreender os significados atribuídos pelo estudante a esses conceitos. Conclui-se, a partir da avaliação diagnóstica, que a maioria dos estudantes pesquisados apresentou dificuldades em expor conceitos científicos sobre o tema Terra e Universo ao iniciar a 6ª série. Entretanto, foram identificadas ideias e representações relevantes que contribuíram para a (re)significação dos conceitos científicos propostos para o ensino do tema nessa série. Os resultados da avaliação diagnóstica serviram como referência para a organização do plano de ensino, viabilizando o processo de aprendizagem, por adequar a sequência didática às características dos estudantes e ao contexto da sala de aula. É esperado que o instrumento apresentado nesse artigo possa ser utilizado também por outros pesquisadores em investigações relacionadas ao tema.

  20. Comments on "Synthesis aspects, structural, spectroscopic, antimicrobial and room temperature ferromagnetism of zinc iodide complex with Schiff based ligand" by K. Shakila and S. Kalainathan, Spectrochim. Acta 135 A (2015) 1059-1065.

    PubMed

    Srinivasan, Bikshandarkoil R; Nadkarni, V S

    2016-06-15

    Shakila and Kalainathan report on the synthetic and structural aspects of a zinc iodide complex with Schiff based ligand, which exhibits room temperature ferromagnetism. In this comment, many points of criticism, concerning the characterization of this so called zinc iodide complex of Schiff based ligand are highlighted to prove that the title paper is completely erroneous. PMID:27037763

  1. Comments on "Synthesis aspects, structural, spectroscopic, antimicrobial and room temperature ferromagnetism of zinc iodide complex with Schiff based ligand" by K. Shakila and S. Kalainathan, Spectrochim. Acta 135 A (2015) 1059-1065

    NASA Astrophysics Data System (ADS)

    Srinivasan, Bikshandarkoil R.; Nadkarni, V. S.

    2016-06-01

    Shakila and Kalainathan report on the synthetic and structural aspects of a zinc iodide complex with Schiff based ligand, which exhibits room temperature ferromagnetism. In this comment, many points of criticism, concerning the characterization of this so called zinc iodide complex of Schiff based ligand are highlighted to prove that the title paper is completely erroneous.

  2. Comment on "Behavior of Re and Os during contact between an aqueous solution and oil: Consequences for the application of the Re-Os geochronometer to petroleum" [Geochim. Cosmochim. Acta 158 (2015) 1-21

    NASA Astrophysics Data System (ADS)

    Wu, Jia; Li, Zhen; Wang, Xuan-ce

    2016-08-01

    In a recent study, Mahdaoui et al. (2015) simulated the contact of oil with Re/Os-bearing aqueous fluids in petroleum reservoirs and concluded that both metals could be rapidly and substantially enriched in the oil fraction. These findings could have significant geological ramifications for the use of rhenium-osmium (Re-Os) geochronology in the age-dating of oil deposits. However, the lack of data reproducibility between parallel experiments and misused parameter of "recovery rate" has cast doubt on the main conclusions of the paper. Re-analyses of the raw data provided sufficient evidence to suggest that in petroleum basins with very low abundances of Re and Os, the extraction of these metals to oil is unlikely to be a geologically instantaneous process as the authors implied in their study. In addition, the possibility of reactor leakage in the contacting experiments cannot be completely ruled out.

  3. Coping with Social Change: Programs That Work. Proceedings of a Conference (Acapulco, Mexico, June 1989) = Como enfrentarse al cambio social: programas eficaces. Actas de uno Conferencia (Acapulco, Mexico, Junio de 1989).

    ERIC Educational Resources Information Center

    Hoskins, Irene, Ed.

    Written in English and Spanish, this document contains the proceedings of the 14th International Congress of Gerontology on concerns about the impact of rapid social change on the well-being of older women and families in Latin American and the Caribbean and about effective programs that address the needs of the older populations. The first…

  4. Corrigendum to "Recycling of crustal material by the Iceland mantle plume: New evidence from nitrogen elemental and isotope systematics of subglacial basalts" [Geochim. Cosmochim. Acta 176 (2016) 206-226

    NASA Astrophysics Data System (ADS)

    Halldórsson, Sæmundur A.; Hilton, David R.; Barry, Peter H.; Füri, Evelyn; Grönvold, Karl

    2016-08-01

    In Table 1 of the above published paper, N2/40Ar* ratios (column 13) are incorrect. A corrected table and updated figures (Figs. 6-8) are shown below. The correct N2/40Ar* values vary between 178 and 2.6 × 104, with a mean of 4.1 ± 2.1 (×103). Although this range in N2/40Ar* ratios is somewhat smaller compared to what was reported, it still displays considerably more heterogeneity compared to the DMM database. The new mean value is also significantly higher than the DMM mean (138 ± 65), as discussed. Therefore, the findings in the paper concerning heterogeneous and elevated N2/40Ar* ratios in Icelandic subglacial basalts still stand.

  5. Corrigendum to "Historical review: Anders Jonas Ångström and the foundation of spectroscopy - Commemorative article on the second centenary of his birth" [Spectrochim. Acta Part B, 102 (2014) 12-23

    NASA Astrophysics Data System (ADS)

    Reif-Acherman, Simón

    2015-07-01

    The following addendum should be added to the Acknowledgments of the above article. Due to the multiplicity of simultaneous activities in which I am continuously involved, I forgot mentioning that Prof. Dr. Klaus Hentschel, of the History Department of the University of Stuttgart (Germany) was helpful in obtaining some of the source material used in my review. In particular, Prof. Hentschel provided the scans of Anne Beckmann's work to which I was guided by passages in his book on "Mapping the spectrum", Oxford University Press (2002). I also followed his recommendation of contacting the Swedish historians of science, and Prof. Sven Widmalm among them; however, the correspondence was not successful.

  6. Corrigendum to "Isotopic and geochemical characterization of fossil brines of the Cambrian Mt. Simon sandstone and Ironton-Galesville formation from the Illinois Basin, USA" [Geochim. Cosmochim. Acta 165 (2015) 342-360

    NASA Astrophysics Data System (ADS)

    Labotka, Dana M.; Panno, Samuel V.; Locke, Randall A.; Freiburg, Jared T.

    2016-08-01

    The original Fig. 4 incorrectly represented data from Clayton et al. (1966). The deuterium values were reported in percent deuterium and mistaken by the authors as per mille. The corrected Fig. 4 Corrigendum is given and shows the data from Clayton et al. (1966) plotting in a similar manner as other published data for groundwater in the Illinois Basin. The data from Clayton et al. (1966) was not used in the discussion of the deep-seated Cambrian brines, and, therefore, this misrepresentation does not affect the conclusions of the original manuscript. The authors apologize for the oversight.

  7. Actas de la 4th mesa redonda sobre investigacion en "Lenguas Extranjeras" en la Universidad Autonoma Metropolitana 1996. (Proceedings from the 4th Roundtable on Investigation in Foreign Languages in the Autonomous Metropolitan University 1996).

    ERIC Educational Resources Information Center

    Zoreda, Margaret Lee, Comp.; Diop, Mamoudou Si, Comp.; Vivaldo Lima, Javier, Comp.

    The articles included in this volume were selected as exemplary papers from the conference in Mexico. The goal of the forum was to provide an opportunity for researchers from the three branches of the Universidad Autonoma Metropolitana (UAM) to meet and discuss research projects currently in progress at the university. The works presented here…

  8. Corrigendum to ‘Evidence for shock heating and constraints on Martian surface temperatures revealed by 40Ar/39Ar thermochronometry of Martian meteorites’ [Geochim. Cosmochim. Acta (2010) 6900–6920

    DOE PAGESBeta

    Cassata, William S.; Shuster, David L.; Renne, Paul R.; Weiss, Benjamin P.

    2014-10-23

    Here, the authors regret they have discovered errors in Eq. (3) and in a spreadsheet used to calculate cosmogenic exposure ages shown in Table 1. Eq. (3) is missing a term. The spreadsheet errors concerned an incorrect cell reference and application of Eq. (3). Correction of these errors results in ~15–20% changes to the exposure ages of all samples, minor (generally <0.2%) changes to the radioisotopic ages of some samples (those that entailed a correction for chlorine-derived 38Ar calculated based on the exposure age; see Section 3.3), and statistically insignificant changes to the inferred trapped components identified through isochron analyses.more » These modifications have no impact on the modeling, discussions, or conclusions in the paper, nor do the changes to radioisotopic ages exceed the 1 sigma uncertainties.« less

  9. Corrigendum to ‘Evidence for shock heating and constraints on Martian surface temperatures revealed by 40Ar/39Ar thermochronometry of Martian meteorites’ [Geochim. Cosmochim. Acta (2010) 6900–6920

    SciTech Connect

    Cassata, William S.; Shuster, David L.; Renne, Paul R.; Weiss, Benjamin P.

    2014-10-23

    Here, the authors regret they have discovered errors in Eq. (3) and in a spreadsheet used to calculate cosmogenic exposure ages shown in Table 1. Eq. (3) is missing a term. The spreadsheet errors concerned an incorrect cell reference and application of Eq. (3). Correction of these errors results in ~15–20% changes to the exposure ages of all samples, minor (generally <0.2%) changes to the radioisotopic ages of some samples (those that entailed a correction for chlorine-derived 38Ar calculated based on the exposure age; see Section 3.3), and statistically insignificant changes to the inferred trapped components identified through isochron analyses. These modifications have no impact on the modeling, discussions, or conclusions in the paper, nor do the changes to radioisotopic ages exceed the 1 sigma uncertainties.

  10. Corrigendum to "Synthesis and spectral characterization of new homologous 1,3,5-triaryl-2-pyrazolines: Influence of alkyloxy chain length on fluorescence" [Spectrochim. Acta Part A: Mol. Biomol. Spectrosc. 133 (2014) 182-189

    NASA Astrophysics Data System (ADS)

    Abbas, Asghar; Hussain, Safdar; Hafeez, Noureen; Naseer, Muhammad Moazzam

    2015-03-01

    The authors regret to inform that the affiliation of one of the authors, namely, Noureen Hafeez has been written as Department of Forensic Medicine & Toxicology, Rawalpindi Institute of Health Sciences (RIHS), Bahria University, Islamabad, Pakistan in the published article. The correct address is shown above.

  11. Western Hemisphere Conference on Persons with Disabilities. Conference Proceedings (Washington, D.C., March 14-18, 1993) = Conferencia Hemisferica Occidental sobre Personas con Discapacidades. Actas de la Conferencia. (Washington, D.C., 14 al 18 de Marzo de 1993).

    ERIC Educational Resources Information Center

    Kelley, Jerry D., Ed.; And Others

    This document presents the proceedings of a conference which brought together delegates and First Ladies representing western hemisphere nations to address needs and issues affecting people with disabilities in the Americas. It presents the texts of two keynote addresses: "Small Triumphs, Big Victories: A Global View of Persons with Disabilities,"…

  12. Corrigendum to "Basin-scale controls on the molybdenum-isotope composition of seawater during Oceanic Anoxic Event 2 (Late Cretaceous)" [Geochim. Cosmochim. Acta 178 (2016) 291-306

    NASA Astrophysics Data System (ADS)

    Dickson, Alexander J.; Jenkyns, Hugh C.; Porcelli, Donald; van den Boorn, Sander; Idiz, Erdem; Owens, Jeremy D.

    2016-09-01

    A recent molybdenum-isotope estimate of the extent of anoxic and euxinic conditions in the world ocean during Oceanic Anoxic Event 2 (∼94 Ma) concluded by discussing a contrast between the new results with existing estimates of marine euxinia based on sulphur isotopes. This suggested contrast was erroneous; when areal extents of marine anoxia and euxinia are calculated for both isotopic proxies, the agreement is actually striking, and highlights the fact that large areas of the global ocean probably remained well ventilated during this event.

  13. Corrigendum to "Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells" [Spectrochim. Acta A Mol. Biomol. Spectrosc. 128 (2014) 420-426

    NASA Astrophysics Data System (ADS)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2015-05-01

    The authors regret to inform that the following text in page No. 425, "The conventionally prepared TiO2 based DSSC exhibits the observed values of Isc = 1.6 mA cm-2, Voc = 0.48 V and the calculated value of FF is 64.32%. Similarly, for pre dye treated TiO2 based DSSC, the observed values of Isc = 2.99 mA cm-2, Voc = 0.50 V and the calculated value of FF is 66.9%" should be read as, "The conventionally prepared TiO2 based DSSC exhibits the observed values of Isc = 2.99 mA cm-2, Voc = 0.50 V and the calculated value of FF is 66.9%. Similarly, for pre dye treated TiO2 based DSSC, the observed values of Isc = 4.2 mA cm-2, Voc = 0.56 V and the calculated value of FF is 62.5%". Though the text is typed wrongly, the I-V graph, the discussions and our conclusions are as same as that of our published article.

  14. Derechos Educacionales de los Padres: Una Explicacion de los Procedimientos de Seguridad para los Padres de Ninos con Discapacidades. Bajo la Clausula del Acta de Educacion para Individuos con Discapacidades (IDEA) y las Reglas para la Administracion del Acta de Educacion para Ninos Excepcionales (Educational Rights of Parents: An Explanation of Procedural Safeguards Available to Parents of Children with Disabilities. Under Provisions of the Individuals with Disabilities Education Act (IDEA) and the Rules for the Administration of the Exceptional Children's Educational Act [ECEA]).

    ERIC Educational Resources Information Center

    Mountain Plains Regional Resource Center, Des Moines, IA.

    This pamphlet, in Spanish, describes Colorado parents' educational rights under federal and state special education rules and regulations. It addresses: (1) free appropriate public education and termination of services; (2) required prior notice to parents if there is a proposed change or refusal to change a child's special education program; (3)…

  15. NATIONAL STORMWATER CALCULATOR USER’S GUIDE – VERSION 1.1

    EPA Science Inventory

    The National Stormwater Calculator is a simple to use tool for computing small site hydrology for any location within the US. It estimates the amount of stormwater runoff generated from a site under different development and control scenarios over a long term period of historica...

  16. Lecturas sobre educacion de adultos en America latina (Readings on Adult Education in Latin America). Serie: Retablo de Papel 14.

    ERIC Educational Resources Information Center

    Latapi, Pablo, Comp.; Castillo, Alfonso, Comp.

    Twelve essays written in Spanish on the state of adult education in Latin America are presented. The essays are organized into three main sections, including: "Concepto y evolucion historica de la educacion de adultos" (Conception and Historical Evolution of Adult Education); "Aspectos particulares" (Specific Subjects); and "Tendencias y…

  17. Astronomy at School: Measurements of the Earth-Moon Distance. (Spanish Title: Astronomía en la Escuela: Medición de la Distancia Tierra-Luna.) Astronomia na Escola: Medida da Distância Terra-Lua

    NASA Astrophysics Data System (ADS)

    Paolantonio, Santiago; Pintado, Olga I.

    2006-12-01

    The aim of this project is to approach High School students to Science. We propose to measure the Earth-Moon distance using the parallax. The observation and measurements techniques and all the calculations needed are described in this paper. The results obtained in a test experience realized during 2003 are presented. This test shows that this is a feasible project and also shows which things needed to be improved. Se plantea la propuesta de un proyecto educativo dirigido al Nivel Medio de enseñanza, consistente en la determinación de la distancia Tierra - Luna por paralaje. Se describen las técnicas de observación, mediciones y cálculos. Se proporcionan a continuación los resultados obtenidos en la experiencia piloto realizada en el 2003, la que permitió comprobar la factibilidad de llevar a cabo la propuesta, así como perfeccionar los diferentes aspectos involucrados en la misma. Propomos neste trabalho um projeto educativo dirigido ao Ensino Médio que consiste na determinação da distância Terra-Lua pelo efeito da paralaxe. As técnicas de observação, medidas e cálculos auxiliares são descritos, e os resultados obtidos numa experiência-teste realizada no ano de 2003 apresentados. Este último teste permitiu comprovar a viabilidade de execução da proposta e aperfeiçoar diversos aspectos da mesma.

  18. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    We present the results obtained in a research on the comprehension of basic astronomical concepts, in which 561 students from fifth grade middle school to third grade high school of a public school of the city of Foz do Iguaçu (Brazil) took part. A test with 20 multiple-choice questions was applied to indentify the most common conceptions expressed by the students. This test was elaborated based on the literature about misconceptions and covered the following topics: the day-night cycle; the time zones; the seasons of the year; the phases of the Moon; the movement of the Moon; the apparent movement of the Sun in the celestial sphere; the eclipses; the dimensions and distances in the Universe; the brightness of the stars and its observation from Earth. Though a small progress was verified in the proportion of scientifically acceptable answers when comparing the eighth grade of middle school to the fifth, and the third grade of high school to the first, there was an overall predominance of alternative conceptions regarding most of the explored subjects, which persisted up to the last year of secondary school. The comparison to data found in this research made in other socio-cultural contexts revealed, in many aspects, similar notions and difficulties revealed by the students. Se presentan los resultados de una investigación sobre la comprensión de conceptos astronómicos básicos, en la cual participaron 561 estudiantes que cursaban entre el quinto grado de la enseñanza primaria y el tercer año de la enseñanza secundaria de una escuela pública de la ciudad de Foz do Iguaçu (Brasil). Se utilizó un test de 20 preguntas de opción múltiple para identificar las concepciones más comunes expresadas por los estudiantes. Este instrumento de recolección de datos se desarrolló en base a la literatura sobre las concepciones alternativas y trató los siguientes temas: el ciclo día-noche, los husos horarios, las estaciones del año, las fases de la Luna, el movimiento de la Luna, el movimiento aparente del Sol sobre la esfera celeste, los eclipses, las dimensiones y las distancias en el Universo, el brillo de las estrellas y su observación de la Tierra. Si bien ha habido un pequeño progreso en la proporción de respuestas aceptables científicamente cuando se cotejó el octavo grado de la enseñanza primaria con el quinto, y el último año de la enseñanza secundaria con el primero, se observó un predominio de las concepciones alternativas en relación a la mayoría de los temas explorados, que continuó hasta los últimos años de la educación básica. Una comparación con los datos encontrados en investigaciones realizadas en otros contextos socioculturales revelaron, en muchos aspectos, conceptos y dificultades similares expresadas por los estudiantes. Apresentam-se os resultados de uma investigação sobre a compreensão de conceitos astronômicos básicos, da qual participaram 561 estudantes da quinta série do Ensino Fundamental ao terceiro ano do Ensino Médio de uma escola pública da cidade de Foz do Iguaçu. Um teste com 20 questões de múltipla escolha foi aplicado para identificar as concepções mais comuns expressadas pelos alunos. Esse instrumento de coleta de dados foi elaborado com base na literatura sobre concepções alternativas e abordou os seguintes temas: o ciclo dia-noite; os fusos horários; as estações do ano; as fases da Lua; o movimento da Lua; o movimento aparente do Sol na esfera celeste; os eclipses; as dimensões e distâncias no Universo; o brilho das estrelas e sua observação da Terra. Embora se tenha verificado um pequeno progresso na proporção de respostas cientificamente aceitáveis ao se cotejar a oitava série do Ensino Fundamental com a quinta, e a terceira série do Ensino Médio com a primeira, houve o predomínio de concepções alternativas em relação à maior parte dos temas explorados, as quais persistiram até o último ano da Educação Básica. A comparação com dados encontrados em investigações realizadas em outros contextos socioculturais revelaram, em muitos aspectos, noções e dificuldades similares manifestadas pelos estudantes.

  19. Instrumentation for Astronomy Teaching: Projecting the Sun Image. (Spanish Title: Instrumentación Para la Enseñanza de Astronomía: Proyectando la Imagen del Sol.) Instrumentação Para O Ensino de Astronomia: Projetando a Imagem do Sol

    NASA Astrophysics Data System (ADS)

    Catelli, Francisco; Giovan, Odilon; Balen, Osvaldo; Siqueira da Silva, Fernando

    2009-07-01

    In this work we describe a simple optical device to project the Sun image which is useful for solar eclipses observing and for sunspots' size estimating.

    Se describe un dispositivo óptico simple para proyectar la imagen del Sol, lo cual es apropiado para las observaciones de eclipses solares y para estimar las dimensiones de las manchas solares.

    É descrito um dispositivo ótico simples para projetar a imagem do Sol, adequado para observações de eclipses solares e à estimativa do tamanho das manchas solares.

  20. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    We present the results obtained in a research on the comprehension of basic astronomical concepts, in which 561 students from fifth grade middle school to third grade high school of a public school of the city of Foz do Iguaçu (Brazil) took part. A test with 20 multiple-choice questions was applied to indentify the most common conceptions expressed by the students. This test was elaborated based on the literature about misconceptions and covered the following topics: the day-night cycle; the time zones; the seasons of the year; the phases of the Moon; the movement of the Moon; the apparent movement of the Sun in the celestial sphere; the eclipses; the dimensions and distances in the Universe; the brightness of the stars and its observation from Earth. Though a small progress was verified in the proportion of scientifically acceptable answers when comparing the eighth grade of middle school to the fifth, and the third grade of high school to the first, there was an overall predominance of alternative conceptions regarding most of the explored subjects, which persisted up to the last year of secondary school. The comparison to data found in this research made in other socio-cultural contexts revealed, in many aspects, similar notions and difficulties revealed by the students. Se presentan los resultados de una investigación sobre la comprensión de conceptos astronómicos básicos, en la cual participaron 561 estudiantes que cursaban entre el quinto grado de la enseñanza primaria y el tercer año de la enseñanza secundaria de una escuela pública de la ciudad de Foz do Iguaçu (Brasil). Se utilizó un test de 20 preguntas de opción múltiple para identificar las concepciones más comunes expresadas por los estudiantes. Este instrumento de recolección de datos se desarrolló en base a la literatura sobre las concepciones alternativas y trató los siguientes temas: el ciclo día-noche, los husos horarios, las estaciones del año, las fases de la Luna, el movimiento de la Luna, el movimiento aparente del Sol sobre la esfera celeste, los eclipses, las dimensiones y las distancias en el Universo, el brillo de las estrellas y su observación de la Tierra. Si bien ha habido un pequeño progreso en la proporción de respuestas aceptables científicamente cuando se cotejó el octavo grado de la enseñanza primaria con el quinto, y el último año de la enseñanza secundaria con el primero, se observó un predominio de las concepciones alternativas en relación a la mayoría de los temas explorados, que continuó hasta los últimos años de la educación básica. Una comparación con los datos encontrados en investigaciones realizadas en otros contextos socioculturales revelaron, en muchos aspectos, conceptos y dificultades similares expresadas por los estudiantes. Apresentam-se os resultados de uma investigação sobre a compreensão de conceitos astronômicos básicos, da qual participaram 561 estudantes da quinta série do Ensino Fundamental ao terceiro ano do Ensino Médio de uma escola pública da cidade de Foz do Iguaçu. Um teste com 20 questões de múltipla escolha foi aplicado para identificar as concepções mais comuns expressadas pelos alunos. Esse instrumento de coleta de dados foi elaborado com base na literatura sobre concepções alternativas e abordou os seguintes temas: o ciclo dia-noite; os fusos horários; as estações do ano; as fases da Lua; o movimento da Lua; o movimento aparente do Sol na esfera celeste; os eclipses; as dimensões e distâncias no Universo; o brilho das estrelas e sua observação da Terra. Embora se tenha verificado um pequeno progresso na proporção de respostas cientificamente aceitáveis ao se cotejar a oitava série do Ensino Fundamental com a quinta, e a terceira série do Ensino Médio com a primeira, houve o predomínio de concepções alternativas em relação à maior parte dos temas explorados, as quais persistiram até o último ano da Educação Básica. A comparação com dados encontrados em investigações realizadas em outros contextos socioculturais revelaram, em m

  1. The Behaviors that College Students Classify as Political Bias: Preliminary Findings and Implications

    ERIC Educational Resources Information Center

    Tollini, Craig

    2009-01-01

    There have been a number of recently published books and reports about the existence of a liberal bias in academia (e.g., ACTA 2005, ACTA 2006, Berube 2006, Black 2004, Horowitz 2006, Horowitz 2008, and Shapiro 2004). Sociology is one of the disciplines that is most frequently cited as "producers" of bias in two of these studies (ACTA 2006,…

  2. Reply to the comment by Wu et al. (2016) on "Behavior of Re and Os during contact between an aqueous solution and oil: Consequences for the application of the Re-Os geochronometer to petroleum" [Geochim. Cosmochim. Acta 158 (2015) 1-21

    NASA Astrophysics Data System (ADS)

    Reisberg, Laurie; Michels, Raymond; Mahdaoui, Fatima

    2016-08-01

    We reply here to the questions raised by Wu et al. concerning the results published by Mahdaoui et al. (2015). This paper describes experiments in which aqueous solutions containing ReO4- and OsCl62- were brought in contact with natural oils at various ranges of concentration, time and temperature. The main observation is that the transfer of Re and Os to oils is very efficient under all experimental conditions. Wu et al. argue that thermodynamic equilibrium was not achieved in these experiments as apparent partition coefficients are inconsistent. They conclude that the experiments were flawed by possible leaking of reactors and that the conclusions by Mahdaoui et al. (2015) were not justified. In the following reply we explain that Mahdaoui et al. (2015) never claimed that thermodynamic equilibrium was achieved. Any calculations or considerations in this context are therefore meaningless. We recall the objectives of our publication, which were to experimentally test the behavior of ReO4- and OsCl6- (two plausible chemical forms of Re and Os in deep aquifers of petroleum systems) in aqueous solution-oil systems. To our knowledge these are the first experiments of their kind. The parameters that could influence the precision and reproducibility of our results were discussed in detail in Mahdaoui et al. (2015). The essential point is that all 60 of the experiments provide evidence of substantial transfer of Re and Os from water to oil. In contrast to what was mistakenly understood by Wu et al., the paper does not challenge the use of Re-Os to date geological events affecting petroleum. Instead, by providing a mechanism that might allow Os isotopic homogenization on a basin-wide scale, a critical step missing from most current models, it offers a possible explanation of how Re-Os geochronology in oils could potentially work. More generally, our study suggests that transfer of Re and Os from waters to oil may be an important phenomenon that should not be overlooked.

  3. Comment on "Structural and vibrational studies on 1-(5-Methyl- [1,3,4] thiadiazol-2-yl)-pyrolidin-2-ol" [Spectrochimica Acta Part A, 152 (2016) 252-261]. The importance of intramolecular OH ⋯ N hydrogen bonding in the conformational properties of thiadiazol-pyrrolidin-2-ol bearing species

    NASA Astrophysics Data System (ADS)

    Laurella, Sergio L.; Erben, Mauricio F.

    2016-07-01

    The title paper [1] reports a study on the spectroscopic and physicochemical properties of 1-(5-methyl- [1,3,4]thiadiazol-2-yl)-pyrrolidin-2-ol (MTPN) based on experimental and theoretical data. The latter ones are based on the computed molecular structure for a rather unusual conformer. Here, after a careful analysis of the conformational space of MTPN, the most stable conformation was determined for the molecule isolated in a vacuum, which results to be 21.9 kJ/mol more stable than the conformer reported previously. Our study also includes the closely related species 1-(5-trifluoromethyl- [1,3,4]thiadiazol-2-yl)-pyrrolidin-2-ol (FMTPN). An intramolecular OH ⋯ N hydrogen bond determines the conformational behavior of the [1,3,4]thiadiazol-2-yl)-pyrrolidin-2-ol group as demonstrated by Natural Bond Orbital population analysis.

  4. Guia del Proceso del IFSP de Colorado: Conexiones para la Ninez Temprana, Iniciativa Infantil de Colorado Parte C del Acta de Educacion para Individuos con Desabilidades (Colorado Guidelines for the IFSP Process: Early Childhood Connections, Colorado's Infant/Toddler Initiative for Part C of the Individuals with Disabilities Education Act).

    ERIC Educational Resources Information Center

    Miller, Jerri; Petersen, Sandy

    This booklet for Spanish-speaking parents of young children with disabilities describes Colorado's Individualized Family Service Plan (IFSP) process. It explains guidelines, shares family stories and reflections for families and care providers, and the describes the values that drive the IFSP process in Colorado. Information is provided on…

  5. Comment on "Structural and vibrational studies on 1-(5-Methyl- [1,3,4] thiadiazol-2-yl)-pyrolidin-2-ol" [Spectrochimica Acta Part A, 152 (2016) 252-261]. The importance of intramolecular OH⋯N hydrogen bonding in the conformational properties of thiadiazol-pyrrolidin-2-ol bearing species.

    PubMed

    Laurella, Sergio L; Erben, Mauricio F

    2016-07-01

    The title paper [1] reports a study on the spectroscopic and physicochemical properties of 1-(5-methyl- [1,3,4]thiadiazol-2-yl)-pyrrolidin-2-ol (MTPN) based on experimental and theoretical data. The latter ones are based on the computed molecular structure for a rather unusual conformer. Here, after a careful analysis of the conformational space of MTPN, the most stable conformation was determined for the molecule isolated in a vacuum, which results to be 21.9kJ/mol more stable than the conformer reported previously. Our study also includes the closely related species 1-(5-trifluoromethyl- [1,3,4]thiadiazol-2-yl)-pyrrolidin-2-ol (FMTPN). An intramolecular OH⋯N hydrogen bond determines the conformational behavior of the [1,3,4]thiadiazol-2-yl)-pyrrolidin-2-ol group as demonstrated by Natural Bond Orbital population analysis. PMID:27070529

  6. [Role of Activin A and Myostatin in cancer cachexia].

    PubMed

    Thissen, Jean-Paul; Loumaye, Audrey

    2013-05-01

    Recent works suggest that Activin A (ActA) and Myostatin (Mstn), two members of the TGFβ superfamily, could contribute to skeletal muscle atrophy observed in some cancers. It is known that several human tumoral cell lines synthesize and secrete ActA and Mstn. In addition, systemic treatment with ActA and Mstn in mice induce muscle atrophy. Likewise, Inhibin-α knock-out mice, which are characterized by elevated circulating levels of ActA, exhibit muscle atrophy and die of cachexia. Finally, administration of ActA and Mstn antagonists prevents muscular atrophy and mortality induced by some animal tumors. Collectively, these findings suggest that ActA or Mstn production by several cancers could contribute to cachexia and thus to mortality associated with some cancers in human. This hypothesis is very interesting since new molecules that are able to inhibit ActA and Mstn, in particularly the sActRIIB, are under development. PMID:23566617

  7. Projeto educação em ciências com observatórios virtuais: a participação da Escola Moppe no período 2000-2003

    NASA Astrophysics Data System (ADS)

    Wuensche, C. A.; Gavioli, E.; Oliveira, A. L. P. R. S.; da Silva, C.; Cardoso, H. P.; Estácio, S.

    2003-08-01

    O projeto Educação em Ciências com Observatórios Virtuais foi concebido pelo Instituto Astronômico e Geofísico da USP, agregando diversas instituições de ensino e pesquisa no país para desenvolver competências diversas na educação fundamental, média e superior utilizando a astronomia como ferramenta multidisciplinar. Este trabalho descreve a participação da MOPPE, escola-piloto do INPE no projeto, no período de 2000-2003. Serão apresentadas 1) a criação de um clube de ciências (1999 a 2001) cujo tema foi a colonização de Marte e 2) a ementa de astronomia trabalhada com as 7a. e 8a. séries do ensino fundamental. A proposta do projeto Colonizando Marte foi estudar diversos aspectos de uma missão interplanetária e construir experiementos que permitissem quantificar esses aspectos. Os resultados obtidos incluiram apresentações nas SBPC Jovem em 2000 e 2001. Discutiremos também as ementas de astronomia trabalhadas desde 2001 e o envolvimento dos alunos com atividades ligadas a astronomia, fora da aula de ciências. A inclusão de astronomia no currículo das últimas séries motivou a participação de mais alunos culminando com a conquista de duas medalhas para alunos da 7a. série na Olimpiada Brasileira de Astronomia em 2002. Houve também um aumento no número de participantes na OBA 2003 e nos projetos de astronomia mais elaborados nas Feira de Ciências de 2001 e 2002. Destacamos em 2003 a inclusão da MOPPE no projeto TIE - Telescopes in Education - da NASA, que utiliza o telescópio do Observatório de Mount Wilson (EUA) para observações remotas em projetos pedagógicos para o ensino de astronomia.

  8. We Do Not Forget Johannes Kepler

    NASA Astrophysics Data System (ADS)

    Wszołek, B.

    2009-12-01

    Year 2009 was announced as the International Year of Astronomy. This was to mark 400th anniversary of the first astronomical observation through a telescope by Galileo. From the other hand, this year marks 400th anniversary of Astronomia Nova, the famous work of Kepler published in Prague in 1609. Two laws of planetary motions opened human efforts to understand gravitational force; so the overall cosmic space conquest, with its great importance not only for astronomy, was developed thankful to Kepler's work. This contribution is thought to show the most inspiring ideas of Johannes Kepler, published in Astronomia Nova and in other his books.

  9. Erratum: Wise Detections of Known Qsos at Redshifts Greater than Six

    NASA Technical Reports Server (NTRS)

    Blain, Andrew W.; Assef, Roberto; Stern, Daniel K.; Tsai, Chao-Wei; Eisenhardt, Peter; Bridge, Carrie; Benford, Dominic J; Jarrett, Tom; Cutri, Roc; Petty, Sara; Wu, Jingwen; Wright, Edward L.

    2014-01-01

    In the published version of this paper, Roberto Assef was mistakenly affiliated with the Division of Astronomy and Astrophysics at the University of California, Los Angeles. This is incorrect. Dr. Assef's affiliation correctly appears in this erratum as the Nucleo de Astronomia de la Facultad de Ingenieria, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile. IOP Publishing sincerely regrets this error.

  10. Tycho Brahe and the Republic of Venice: a failed project

    NASA Astrophysics Data System (ADS)

    Pigatto, Luisa

    In 1592 the Senate of the Republic of Venice issued a decree by which awarded Tycho Brahe `300 coronati' for an astronomical mission to Alexandria in Egypt. The aim was to measure the pole elevation with meridian observations both of Sun and stars. Tycho writes about this project, never carried into execution, in his Astronomiae Instauratae Mechanica of 1598.

  11. Creativity and Democratic Governance. Adult Learning: A Strategic Choice. Proceedings of the ICAE World Assembly (6th, Ocho Rios, Jamaica, August 9-12, 2001) = Creativite et Gouvernance Democratique. L'apprentissage des Adultes: Un Choix Strategique. Actes de la Assemblee Mondiale du CIEA (6th, Ocho Rios, Jamaique, 9 au 12 aout 2001) = Creatividad y Gobernabilidad Democratica. Educacion de Adultos: Una Eleccion Estrategica. Actas de la Asamblea Mundial del ICAE (6th, Ocho Rios, Jamaica, Agosto 9-12, 2001).

    ERIC Educational Resources Information Center

    Dobson, Stephan, Ed.

    This document contains information from and about a world assembly on creativity and democratic governance in adult learning that was held by the International Council for Adult Education (ICAE) and its partner organizations in the Caribbean. The proceedings begin with English, French, and Spanish translations of the address…

  12. [The death of Ignatius Loyola].

    PubMed

    Huguier, Michel; Lacaine, Francois

    2011-12-01

    A recent examination of a bilioportal fistula led us to suspect a link between this case and the death of Ignatius of Loyola. Realdo Colombo, professor of anatomy, eviscerated Ignatius prior to his embalming In his book De re anatomica, published in 1559, he wrote that he extracted stones from the portal vein of the venerable Ignatius. Before his death, Ignatius suffered from epigastric pain and fever (Monumenta historica societatis Jesu). Colombo latin text is difficult to interpret and the data are meager. Other possible causes of Ignatius' death include gastroduodenal ulcer, tuberculosis and hyperparathyroidism, but despite of rarity bilioportal fistula is the best guess. PMID:22930868

  13. The Vanishing Shakespeare: A Report by the American Council of Trustees and Alumni

    ERIC Educational Resources Information Center

    Neal, Anne D.; Mitchell, Charles

    2007-01-01

    As this report goes to press, the nation's capital is in the midst of a six-moth, city-wide celebration of William Shakespeare. With this celebration as a backdrop, the American Council of Trustees and Alumni (ACTA) researched how Shakespeare fits into English curricula at 70 of the nation's leading colleges and universities. ACTA surveyed English…

  14. Genetics Home Reference: paramyotonia congenita

    MedlinePlus

    ... impact of permanent muscle weakness on quality of life in periodic paralysis: a survey of 66 patients. Acta Myol. 2012 Oct;31(2):126-33. Citation on PubMed or Free article on PubMed Central Finsterer J. Primary periodic paralyses. Acta Neurol Scand. 2008 Mar;117(3):145-58. Epub 2007 Nov 20. ...

  15. Leading the Charge: Governors, Higher Education and Accountability

    ERIC Educational Resources Information Center

    American Council of Trustees and Alumni, 2014

    2014-01-01

    With this new tool, ACTA [American Council of Trustees and Alumni] is working to expand its outreach to governors nationwide on behalf of higher education reform, focusing on key issues of quality, cost, and accountability. ACTA has worked with governors and education leaders from across the country, and that experience has proven that innovative…

  16. Advances in membrane protein crystallography: in situ and in meso data collection

    SciTech Connect

    Weyand, Simone; Tate, Christopher G.

    2015-05-23

    Membrane protein structural biology has made tremendous advances over the last decade but there are still many challenges associated with crystallization, data collection and structure determination. Two independent groups, Axford et al. [(2015), Acta Cryst. D71, 1228–1237] and Huang et al. [(2015), Acta Cryst. D71, 1238–1256], have published methods that make a major contribution to addressing these challenges.

  17. Kepler's "War on Mars"

    NASA Astrophysics Data System (ADS)

    Dorsey, William; Orchiston, W.; Stephenson, F. R.

    2011-01-01

    This paper presents an interpretation of how Johannes Kepler changed the study of astronomy. We propose that in his metaphorical "War on Mars,” the Astronomia Nova, Kepler used a revolutionary rhetoric to bring about the usurpation of seventeenth-century astronomy. We discuss how Kepler approached the well-established conceptual framework within which the hypotheses of Ptolemy, Copernicus and Tycho Brahe functioned, and how he sought comprehensive physical principles that could determine the true cause and form of the known Universe. We examine Kepler's need to redefine reality and his use of rhetoric in shaping his astronomical argument for a new astronomy, and we show that his new `laws’ represent a fusion of physics and geometry based upon astronomical observations. We suggest that although Kepler may have believed in and defended some Copernican ideas, his innovative Astronomia Nova opened up a whole new vista for international astronomy.

  18. The X-ray view of EROs

    NASA Astrophysics Data System (ADS)

    Brusa, M.; Comastri, A.; Daddi, E.; Cimatti, A.; Vignali, C.

    (1) Dip. Astronomia Bologna University, via Ranzani 1, I-40127 Bologna ITALY (2) INAF - Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna ITALY (3) ESO - European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei Muenchen Germany (4) INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-55025 Firenze, Italy (5) Dept. of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA

  19. Stars, Manuscripts, and Astrolabes-The Stellar Constellations in a Group of Medieval Manuscripts between Latin Literature and a New Science of the Stars

    NASA Astrophysics Data System (ADS)

    Metzger, W.

    2011-06-01

    The European Middle Ages inherited star names and constellations from Roman antiquity, mostly via Latin literary texts. When, from the 11th century onwards, Arabic texts and instruments became available, figures and vocabulary at first where not compatible with this tradition. The example of an excerpt from Pseudo-Hyginus De Astronomia shows, how a Roman text on the constellations was revised and supplemented with the names of the astrolabe-stars to combine the two different traditions.

  20. Johannes Kepler in Prague - and a new museum

    NASA Astrophysics Data System (ADS)

    McKim, R.

    2010-06-01

    Four centuries ago in 1610, the Kepler family were living in their last place of residence in Prague, in a house in a courtyard off Karlova Street (Karlova ulice), very close to the east end of Charles Bridge (Karluv most). The house is No.188, U Francouzske koruny (French Crown House), and has a passage through to Anenska Street. Kepler spent 12 years in the city, publishing his most important works including Astronomia Nova.

  1. High circulating activin A level is associated with tumor progression and predicts poor prognosis in lung adenocarcinoma

    PubMed Central

    Hoda, Mir Alireza; Rozsas, Anita; Lang, Elisabeth; Klikovits, Thomas; Lohinai, Zoltan; Torok, Szilvia; Berta, Judit; Bendek, Matyas; Berger, Walter; Hegedus, Balazs; Klepetko, Walter; Renyi-Vamos, Ferenc; Grusch, Michael; Dome, Balazs; Laszlo, Viktoria

    2016-01-01

    Activin A (ActA)/follistatin (FST) signaling has been shown to be deregulated in different tumor types including lung adenocarcinoma (LADC). Here, we report that serum ActA protein levels are significantly elevated in LADC patients (n=64) as compared to controls (n=46, p=0.015). ActA levels also correlated with more advanced disease stage (p<0.0001) and T (p=0.0035) and N (p=0.0002) factors. M1 patients had significantly higher ActA levels than M0 patients (p<0.001). High serum ActA level was associated with poor overall survival (p<0.0001) and was confirmed as an independent prognostic factor (p=0.004). Serum FST levels were increased only in female LADC patients (vs. female controls, p=0.031). Two out of five LADC cell lines secreted biologically active ActA, while FST was produced in all of them. Transcripts of both type I and II ActA receptors were detected in all five LADC cell lines. In conclusion, our study does not only suggest that measuring blood ActA levels in LADC patients might improve the prediction of prognosis, but also indicates that this parameter might be a novel non-invasive biomarker for identifying LADC patients with organ metastases. PMID:26950277

  2. Analysis of astronomy knowledge of the students in the Federal Institute Sao Paulo

    NASA Astrophysics Data System (ADS)

    Moraes, A. C.; Voelzke, M. R.

    2014-08-01

    Este trabalho é parte integrante da pesquisa de mestrado acadêmico em ensino de ciências. Nele, busca-se apresentar os resultados da pesquisa realizada entre os 106 alunos do curso superior de tecnologia em automação industrial do Instituto Federal de Educação, Ciência e Tecnologia de São Paulo campus Cubatão, divididos em cinco turmas, duas no período matutino e três no período noturno. A análise dos resultados deste pré questionárioconstatou a falta de conhecimento básico dos discentes, sobre assuntos relacionados à astronomia, o que pode ser atribuído ao ineficiente processo de aprendizado pelo qual eles passaram tanto no ensino médio como no ensino fundamental, em escolas municipais, estaduais e particulares onde estudaram. No ensino de astronomia, têm-se diagnosticado constantemente diversas dificuldades conceituais tanto por parte de alunos como de professores de todas as áreas e níveis de ensino e poucos de fato a compreendem (ALBRECHT; VOELZKE, 2010). Demonstra-se as duas etapas concluídas do trabalho. A primeira etapa indica a análise dos conhecimentos prévios sobre conceitos astronômicos, através do questionário com 25 perguntas. A fim de corrigir as falhas constatadas, experimentalmente ministrou-se, externo ao conteúdo programático, um curso básico em astronomia, com diferentes estratégias de ensino, tais como, utilização de aulas expositivas dialogadas, recursos audiovisuais e palestras, para corrigir as dificuldades diagnosticadas. Essas estratégias de ensino se comprovaram adequadas às necessidades dos alunos e os conceitos foram finalmente compreendidos. Ao término do curso, completado o interstício de 120 dias, para caracterizar que houve a aprendizagem significativa, realizou-se uma nova pesquisa, quando, exatamente os mesmos 106 alunos responderam as mesmas 25 questões aplicadas na primeira etapa. Constata-se na segunda etapa, após análise, que em todas as questões, houve maior compreensão dos assuntos

  3. USING BIOMONITORING DATA TO INFORM EXPOSURE ASSESSMENT IN CHILDREN

    EPA Science Inventory

    Discussing the challenges associated with estimating and interpreting toxicant exposures and health risks from biomonitoring data. Extended abstract will also be translated in Spanish and published in Acta Toxicologica Argentina.

  4. Uso de los Datos de Biomonitoreo para Informar sobre la Evaluacion Infantil (American translation is: USING BIOMONITORING DATA TO INFORM EXPOSURE ASSESSMENT IN CHILDREN)

    EPA Science Inventory

    Discussing the challenges associated with estimating and interpreting toxicant exposures and health risks from biomonitoring data. This extended abstract was translated in Spanish and published in Acta Toxicologica Argentina.

  5. Genetics Home Reference: glucose-galactose malabsorption

    MedlinePlus

    ... mutations in SGLT1 cause glucose-galactose malabsorption by trafficking defects. Biochim Biophys Acta. 1999 Feb 24;1453( ... Accessibility FOIA Viewers & Players U.S. Department of Health & Human Services National Institutes of Health National Library of ...

  6. Genetics Home Reference: myosin storage myopathy

    MedlinePlus

    ... proteins accumulate in type I skeletal muscle fibers, forming the protein clumps characteristic of the disorder. It ... Epub 2007 Mar 2. Citation on PubMed Tajsharghi H, Oldfors A. Myosinopathies: pathology and mechanisms. Acta Neuropathol. ...

  7. Genetics Home Reference: oculopharyngeal muscular dystrophy

    MedlinePlus

    ... advances in the understanding of the molecular pathogenic mechanisms and treatment strategies. Biochim Biophys Acta. 2007 Feb; ... further evidence for unequal recombination as the mutational mechanism. Hum Genet. 2005 Mar;116(4):267-71. ...

  8. Errors in Crystal structure of HINT from Helicobacter pylori

    PubMed Central

    Maize, Kimberly M.

    2016-01-01

    Inaccuracies in the article, Crystal structure of HINT from Helicobacter pylori by Tarique et al. [(2016) Acta Cryst. F72, 42–48] are presented, and a brief history of HINT nomenclature is discussed. PMID:27050269

  9. VISIÓN GENERAL DE LA EVALUACIÓN DEL RIESGO EN SALUD INFANTIL EMPLEANDO UN ENFOQUE POR ETAPAS DE DESARROLLO (American translation is: Overview of a Life Stage Approach to Children's Health Risk Assessment)

    EPA Science Inventory

    Discussing the challenges associated with estimating and interpreting toxicant exposures and health risks from biomonitoring data. This extended abstract was translated in Spanish and published in Acta Toxicologica Argentina.

  10. Erratum: Di-μ-nitrosyl-bis-[(η-penta-methyl-cyclo-penta-dien-yl)ruthenium(0)](Ru-Ru). Corrigendum.

    PubMed

    Pearsal, Matthew; Gembicky, Milan; Dominiak, Paulina; Larsen, Anna; Coppens, Philip

    2010-01-01

    The acknowledgement in the paper by Pearsal, Gembicky, Dominiak, Larsen & Coppens [Acta Cryst. (2007), E63, m2596] is extended and an omitted reference is added.[This corrects the article DOI: 10.1107/S1600536807045321.]. PMID:21578980

  11. 75 FR 79069 - Anti-Counterfeiting Trade Agreement: Request for Comments From the Public

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-17

    ... practices. Together these provisions will help to protect American jobs in innovative and creative... business confidential information, the filer should type ``ACTA Comments--Business Confidential'' in the ``Type Comment & Upload file'' field. Any page containing business confidential information must...

  12. Qual o Papel da Escola e da Mídia na Obtenção dos Conhecimentos Astronômicos?

    NASA Astrophysics Data System (ADS)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2007-08-01

    É amplamente reconhecido que as pessoas em geral têm grande fascínio e interesse pela Astronomia. Por outro lado, o conteúdo dessa área incluído no ensino formal está longe de ser abrangente e suficiente para suprir a demanda. Esse interesse permite aperfeiçoar a divulgação e o ensino não formal de Astronomia através da mídia aliando a adequação do conteúdo à expectativa das pessoas. A reforma do Currículo Básico da Escola Pública da maioria dos Estados brasileiros tem introduzido Astronomia desde a pré-escola até o Ensino Médio. Num estudo realizado com 1180 alunos do Ensino Médio de seis escolas estaduais, revelou-se através da aplicação de um formulário contendo questões que abordavam conhecimentos básicos em Astronomia, como foram adquiridos tais conhecimentos e à infra-estrutura da escola. Para 66,1% dos entrevistados o professor já fez alguma apresentação a respeito de Astronomia. O presente estudo revelou também que 54,4% dos alunos entrevistados adquiriram seus conhecimentos astronômicos na escola, 18,4% através da televisão e 27,1% afirmaram que seus conhecimentos foram obtidos através de outros tipos de mídia (internet, livros didáticos, filmes e revistas). Embora o estudo revele claramente que há certo equilíbrio no meio em que os alunos obtiveram seus conhecimentos astronômicos, a mídia busca não somente sua difusão, mas a disponibilização desse conhecimento de maneira correta, que às vezes, não é atingido, apresentando conceitos sem fundamentação e incorretos. Por outro lado, no dia-a-dia escolar, é comum encontrar professores que vêm para as aulas com concepções prévias, que podem diferir substancialmente das idéias a serem ensinadas, dificultando o aprendizado de futuros conceitos científicos. Uma avaliação criteriosa, avaliando as dificuldades dos professores em determinar o sentido correto dos conceitos e observando a metodologia que utilizam no ensino, poderá proporcionar uma melhor

  13. Teaching astronomy mediated by information and communication technologies: a preliminary approach

    NASA Astrophysics Data System (ADS)

    Rosa, R. H. L.; Voelzke, M. R.

    2014-08-01

    O presente trabalho é parte preliminar de um estudo mais amplo em nível de doutorado sobre o ensino de astronomia mediado pelas tecnologias da informação e comunicação, utilizando dispositivos compactos, móveis e pessoais. Este estudo também faz parte do projeto institucional do CEFETMG sobre ambientes diversificados de aprendizagem sob fomento da agência estadual FAPEMIG (Fundação de Amparo à Pesquisa do Estado de Minas Gerais). Esta apresentação aborda o resultado das concepções prévias de estudantes em relação a conhecimentos básicos de astronomia, ligados à percepção e observação direta do céu. Três turmas de estudantes de 1ª série e uma turma de 3ª série do ensino integrado médio técnico da Educação Básica, Técnica e Tecnológica (EBTT) do CEFETMG Campus II - Belo Horizonte/MG foram submetidas a uma avaliação prévia através de questionário estruturado. Este questionário foi elaborado de forma a abordar a percepção dos estudantes em relação aos recursos gráficos (figuras e desenhos) representativos de conhecimentos básicos de astronomia, comuns em livros didáticos. Após a análise dos resultados desta avaliação, organizou-se uma estratégia de intervenção didática em sala de aula sobre o conteúdo de astronomia, utilizando-se de recursos de mediação baseados nas tecnologias da informação e comunicação. Os temas selecionados para esta estratégia didática foram relacionados aos assuntos básicos de astronomia em que ocorreu maior nível de desconhecimento dos estudantes. Os estudantes foram submetidos a avaliação posterior elaborada com os mesmos pressupostos da avaliação prévia. A análise dos resultados foi realizada a partir dos pressupostos da aprendizagem significativa (Ausubel; Novak e Hanesian, 1983). O ensino de astronomia por mediação das tecnologias da informação e comunicação indica uma alternativa preliminar aos trabalhos de campo usuais orientados na prática escolar, tais

  14. Johannes Kepler and David Fabricius: Their Discussion on the Nova of 1604

    NASA Astrophysics Data System (ADS)

    Granada, Miguel A.

    David Fabricius (1564-1617) was one of the most important astronomers in the period between 1596, the year of publication of Kepler's Mysterium cosmographicum, and 1609, the year of publication of the Astronomia nova.1 Kepler praised Fabricius as the most accurate observational astronomer after Tycho Brahe's death in 1601.2 Fabricius was a Reformed pastor in Ostfriesland (East Frisia), his remote natal region, and a vocational astronomer. He published nothing in the field of astronomy except for the short treatises between 1604 and 1606 concerning the nova that appeared in October 1604 in Serpentarius.

  15. In Galileo's footsteps

    NASA Astrophysics Data System (ADS)

    Durrani, Matin

    2009-03-01

    Astronomy can lay rightful claim to being the oldest science, with its foundations dating back even further than those of mathematics. From the ancient Babylonians who observed the regular motions of Venus to medieval Islamic scholars who had the first inklings of heliocentrism, the study of the skies has fascinated humankind. But 2009 - the International Year of Astronomy - commemorates an event central to the development of Western science: Galileo Galilei's first observations with a telescope in 1609. This year also marks the 400th anniversary of Johannes Kepler's Astronomia Nova, in which he outlined his laws of planetary motion.

  16. Tycho Brahe: Instruments of the renewed astronomy (set of 3 books).

    NASA Astrophysics Data System (ADS)

    Hadravová, A.; Hadrava, P.; Shackelford, J. R.

    Book 1: Tycho Brahe: Astronomiae Instauratae Mechanica (facsimile) ISBN 80-85917-23-8, 50 p. Book 2: Tycho Brahe: Instruments of the renewed astronomy. English translation based on the edition H. Raeder et al., 1946. Revised, supplemented and commented by authors. XV + 175 p. Chapters: Prologue; note to the new edition; translation; selected bibliography; index of names. Book 3: Czech translation, supplemented by letters of J. Curtius and G. A. Magini to Tycho Brahe; verses by Tycho (passim, in Czech only) translated from Latin and Greek by D. Svobodová. XVI + 190 p.

  17. Uma Visão do Universo Segundo um Grupo de Alunos do Ensino Médio de São Paulo

    NASA Astrophysics Data System (ADS)

    Elias, D. S.; Araújo, M.; Amaral, L. H.; Voelzke, M. R.; Araújo, M.

    2005-08-01

    A astronomia, embora seja uma ciência popular, com inúmeras descobertas de interesse público, ainda é apresentada desconsiderando-se os aspectos históricos e científicos relacionados ao seu desenvolvimento, sendo geralmente veiculada nos meios de comunicação de maneira pouco esclarecedora e não raro com imprecisões. Neste trabalho analisou-se a concepção de um grupo de estudantes de Ensino Médio sobre conceitos de astronomia, visando identificar sua visão de mundo a respeito do Universo, envolvendo idéias sobre espaço e tempo. Para issso, foi aplicado um questionário em três escolas da grande São Paulo em um espaço amostral de 270 alunos. Constatou-se que, embora o ensino de astronomia esteja previsto nos PCNEM, os resultados obtidos na pesquisa mostram que há grande deficiência no conhecimento dos temas investigados. Nesse sentido, verificou-se que apenas 20% dos alunos eram capazes de relacionar a sucessão das semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra. Por outro lado, somente 23% dos alunos tinham noções das distâncias entre os objetos celestes próximos da Terra e 56% conseguiram relacionar o Big Bang com a origem do Universo. Finalmente, constatou-se que 37% reconheciam o ano-luz como uma unidade de distância e 60% reconheciam o Sol como sendo uma estrela. Apesar de 60% dos alunos indicarem que a escola é a principal fonte para aquisição dos conhecimentos de astronomia, conclui-se que seus conceitos nessa área ainda são inadequados, havendo necessidade de ampliação e aprimoramento da abordagem desses conteúdos nos ambientes escolares.

  18. Análise dos Conceitos Astronômicos Apresentados por Professores de Algumas Escolas Estaduais Brasileiras

    NASA Astrophysics Data System (ADS)

    Voelzke, Marcos Rincon; Gonzaga, Edson Pereira

    2011-12-01

    A razão para o desenvolvimento deste trabalho baseia-se no fato de que muitos professores da Educação Básica (EB) não lidam com conceitos relacionados à astronomia, e quando o fazem eles simplesmente seguem livros didáticos que podem conter erros conceituais. Como é de conhecimento geral a astronomia é um dos conteúdos a serem ensinados na EB fazendo parte dos Parâmetros Curriculares Nacionais e das Propostas Curriculares do Estado de São Paulo, mas é um fato, que vários pesquisadores apontam, a existência de muitos problemas no ensino da astronomia. Com o propósito de minimizar algumas dessas deficiências foi realizado um trabalho de pesquisa com a utilização de questionários pré e pós pesquisa, para tanto foi desenvolvido um Curso de Extensão Universitária para professores da Diretoria de Ensino Regional (DE) que abrange Mauá, Ribeirão Pires e Rio Grande da Serra (no Estado de São Paulo) com os seguintes objetivos: levantar concepções alternativas; subsidiar os professores por meio de palestras, debates e workshops, e verificar o sucesso da aprendizagem após o curso, adotando-se como referência, para a análise dos resultados, os dicionários de Língua Portuguesa (FERREIRA, 2004) e Enciclopédico de Astronomia e Astronáutica (MOURĀO, 1995). Portanto, dezesseis questões foram aplicadas antes e após o curso, assim pode-se verificar após a pesquisa que 100,0% dos professores sabiam os nomes das fases da Lua, 97,0% entenderam que o Sistema Solar é composto por oito planetas, 78,1% foram capazes de explicar como ocorre um eclipse lunar, um eclipse solar e um solstício, 72,7% sabiam como explicar a ocorrência das estações do ano; 64,5% explicaram corretamente a ocorrência do equinócio, 89,7% foram capazes de definir adequadamente o termo cometa; 63,6% definiram asteróide, 54,5% meteoro, 58,1% galáxia, e 42,4% planeta. Os resultados obtidos indicam uma aprendizagem significativa por parte dos participantes.

  19. Historical survey of the national astronomical observatory in Llano del Hato

    NASA Astrophysics Data System (ADS)

    Martinez Picar, Antonio; Salas Ramirez, Henry

    2007-12-01

    The Centro de Investigaciones de Astronomia (CIDA), the Venezuelan Institute in charge for managing human- and technical resources of the National Astronomical Observatory in Llano del Hato, is one of the younger institutes in its field. However, its foundation is surrounded by a series of curious and interesting eyents that go back to the end of the 18th century. Its equatoriallocation, excellent astronomical equipment and the high-qualified personnel offers a geographical and technical advantage. The paper is a historical oveniew of events, facts and demonstrations of the human activity related to the conception, building and starting the Llano del Hato National Astronomical Observatory.

  20. Precise detection of L. monocytogenes hitting its highly conserved region possessing several specific antibody binding sites.

    PubMed

    Jahangiri, Abolfazl; Rasooli, Iraj; Reza Rahbar, Mohammad; Khalili, Saeed; Amani, Jafar; Ahmadi Zanoos, Kobra

    2012-07-21

    Listeria monocytogenes, a facultative intracellular fast-growing Gram-positive food-borne pathogen, can infect immunocompromised individuals leading to meningitis, meningoencephalitis and septicaemias. From the pool of virulence factors of the organism, ActA, a membrane protein, has a critical role in the life cycle of L. monocytogenes. High mortality rate of listeriosis necessitates a sensitive and rapid diagnostic test for precise identification of L. monocytogenes. We used bioinformatic tools to locate a specific conserved region of ActA for designing and developing an antibody-antigen based diagnostic test for the detection of L. monocytogenes. A number of databases were looked for ActA related sequences. Sequences were analyzed with several online software to find an appropriate region for our purpose. ActA protein was found specific to Listeria species with no homologs in other organisms. We finally introduced a highly conserved region within ActA sequence that possess several antibody binding sites specific to L. monocytogenes. This protein sequence can serve as an antigen for designing a relatively cheap, sensitive, and specific diagnostic test for detection of L. monocytogenes. PMID:22575546

  1. A proposed contents astronomy for basic education

    NASA Astrophysics Data System (ADS)

    Albrecht, E.; Voelzke, M. R.

    2014-08-01

    A Astronomia é um tema que sempre exerceu fascínio sobre as pessoas de um modo geral. Conhecer e estudar o que há nos “céus”, além de nossos olhos, continua sendo instigador e de grande interesse. Baseado nestas justificativas desenvolveu-se uma pesquisa de Doutorado, na qual, o objetivo principal foi investigar sobre a presença dos conteúdos de Astronomia nas Propostas Curriculares da região Sul do Brasil, a saber, os estados de Paraná, Rio Grande do Sul e Santa Catarina e, posterior comparação com os Parâmetros Curriculares Nacionais (PCN) que trazem propostas de conteúdos para toda a Educação Básica brasileira. Tal investigação pautou-se na abordagem de caráter qualitativo e utilizouse para tal da Análise de Conteúdos (Bardin, 2011), que possibilitou a construção de quatro categorias, nas quais os conteúdos astronômicos foram agrupados: Terra, Sistema Solar, Via Láctea e Universo. Após a leitura, coleta de dados, construção de categorias, observou-se a dicotomia na apresentação destes conteúdos. As propostas curriculares analisadas foram as de Geografia, Ciências e Física dos estados do Paraná (2008), Rio Grande do Sul (2009) e de Santa Catarina (1998), responsáveis pelo trabalho com Astronomia nestes estados. No Ensino Fundamental, a proposta curricular do estado do Paraná apresenta conteúdos ligados à Astronomia desde o sexto ano até o nono ano, como conteúdo do primeiro bimestre, o que também é apresentado na proposta curricular do estado do Rio Grande do Sul, porém, este, não divide os conteúdos por bimestre e nem por ano, mas por ciclos, sexto e sétimo anos como primeiro ciclo e oitavo e nono anos como segundo ciclo, deixando livre para o professor estruturar sua sequência de conteúdos. A proposta curricular de Santa Catarina não apresenta estes conteúdos de maneira explícita, não divide dos conteúdos nem por ano, nem por série, traz uma sequência de conteúdos para serem trabalhados ao longo dos

  2. An undergraduate program for astronomy in México

    NASA Astrophysics Data System (ADS)

    Bravo-Alfaro, Hector; Migenes, Victor

    Astronomy in Mexico has an ancient tradition, reinforced during the XXth century by groups working in theoretical and observational astronomy. During the 90s, the Great Millimeter Telescope (a single 50-m antenna) has been approved, and a 6-m infrared telescope is under study. Graduate and undergraduate programs must be improved to prepare future Mexican and Latin American astronomers to take advantage of these facilities. To meet the challenge, two traditional Mexican programs (Instituto de Astronomia-UNAM and Instituto Nacional de Astrofisica, Optica y Electronica-INAOE) are updating their graduate programs for. Similarly, the Departamento de Astronomia de la Universidad de Guanajuato is joining physicists in the first undergraduate program in Mexico in Physics and Engineering with an option in Astrophysics. This will prepare students so that they can choose between industry, academia or national laboratories, either in Physics or Astronomy. Jobs in academia have been scarce; many students had to give up their goals after one or two postdoctoral positions. Graduate and undergraduate programs must adjust, by broadening the scope of present programs so that students are better prepared for other job opportunities. We present a BSc program designed by astronomers and physicists to try to address some of these concerns and prepare the students for either continuing with graduate studies or finding employment in an ever-changing job market.

  3. A Visão do Universo Segundo a Concepção de um Grupo de Alunos do Ensino Médio de São Paulo

    NASA Astrophysics Data System (ADS)

    Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

    2005-12-01

    Nesse trabalho foi identificada por meio de um questionário a visão de mundo sobre o Universo espaço e tempo entre 270 estudantes de Ensino Médio de três escolas de São Paulo. Constatou-se pouco conhecimento dos temas investigados sendo que apenas 20% dos alunos relacionaram as semanas com as fases da lua enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% reconheciam o Sol como uma estrela. Apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de astronomia seus conceitos ainda são inadequados havendo necessidade de aprimoramento da abordagem desses conteúdos pois apesar de popular a astronomia é veiculada de maneira pouco esclarecedora e com imprecissões.

  4. A Influência da Escola e da Mídia na Obtenção dos Conhecimentos Astronômicos

    NASA Astrophysics Data System (ADS)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2006-08-01

    O universo em que vivemos possui segredos jamais imaginados pelo homem, fruto da pequena proporção que ocupamos diante de um cosmos infinito. A astronomia funciona como um instrumento que sacia a sede humana em desvendar esses segredos, estudando as galáxias, quasares, pulsares além da existência de todos os elementos que preenchem o espaço cósmico, o vácuo, não mais vazio como se pensou em outros tempos. A mídia explora esse campo de forma mística e também científica. A difusão adequada e dentro dos padrões educacionais vigentes, de conceitos astronômicos, se faz necessária, devido sua presença nos conteúdos escolares, centros de ciência e na mídia, de modo geral. A reforma do Currículo Básico da Escola Pública da maioria dos Estados brasileiros introduziu conceitos astronômicos desde a pré-escola até o Ensino Médio. Num estudo realizado com 1.032 alunos do Ensino Médio de seis escolas estaduais, revelou-se através da aplicação de um questionário que abordava conheciment os básicos em astronomia, como estes foram adquiridos e qual era a infra-estrutura oferecida pela escola: para 66,2% dos entrevistados o professor já fez alguma apresentação a respeito de astronomia. O presente estudo revelou também que 44,5% dos alunos entrevistados adquiriram seus conhecimentos astronômicos na escola, 28,1% através da televisão e 27,4% afirmaram que seus conhecimentos foram obtidos através de outros tipos de mídia (internet, filmes e revistas). Embora o estudo revele claramente que há certo equilíbrio na forma em que os alunos obtiveram seus conhecimentos astronômicos, a mídia ainda explora e muitas vezes desperta o interesse pela astronomia com assuntos que não fazem parte de nosso cotidiano como, por exemplo, o homem na Lua, os projetos espaciais e a primeira viagem de um astronauta brasileiro no espaço. Porém, em certos casos, a mídia pode promover conhecimentos incompletos ou mesmo equivocados sobre os conceitos que envolvam

  5. Modulating myosin restores muscle function in a mouse model of nemaline myopathy

    PubMed Central

    Lindqvist, Johan; Levy, Yotam; Pati‐Alam, Alisha; Hardeman, Edna C.; Gregorevic, Paul

    2016-01-01

    Objective Nemaline myopathy, one of the most common congenital myopathies, is associated with mutations in various genes including ACTA1. This disease is also characterized by various forms/degrees of muscle weakness, with most cases being severe and resulting in death in infancy. Recent findings have provided valuable insight into the underlying pathophysiological mechanisms. Mutations in ACTA1 directly disrupt binding interactions between actin and myosin, and consequently the intrinsic force‐generating capacity of muscle fibers. ACTA1 mutations are also associated with variations in myofiber size, the mechanisms of which have been unclear. In the present study, we sought to test the hypotheses that the compromised functional and morphological attributes of skeletal muscles bearing ACTA1 mutations (1) would be directly due to the inefficient actomyosin complex and (2) could be restored by manipulating myosin expression. Methods We used a knockin mouse model expressing the ACTA1 His40Tyr actin mutation found in human patients. We then performed in vivo intramuscular injections of recombinant adeno‐associated viral vectors harboring a myosin transgene known to facilitate muscle contraction. Results We observed that in the presence of the transgene, the intrinsic force‐generating capacity was restored and myofiber size was normal. Interpretation This demonstrates a direct link between disrupted attachment of myosin molecules to actin monomers and muscle fiber atrophy. These data also suggest that further therapeutic interventions should primarily target myosin dysfunction to alleviate the pathology of ACTA1‐related nemaline myopathy. Ann Neurol 2016;79:717–725 PMID:26891371

  6. Scientometric Analysis of the Journals of the Academy of Medical Sciences in Bosnia and Herzegovina

    PubMed Central

    Masic, Izet; Begic, Edin; Zunic, Lejla

    2016-01-01

    Introduction: Currently in Bosnia and Herzegovina there are 25 journals in the field of biomedicine, 6 of them are indexed in Medline/PubMed base (Medical Archives, Materia Socio-Medica, Acta Informatica Medica, Acta Medica Academica, Bosnian Journal of Basic Medical Sciences (BJBMS) and Medical Glasnik), and one (BJBMS) is indexed in Science Citation Index Expanded (SCIE)/Web of Science base. Aim: The aim of this study was to show the scope of work of the journals that were published by Academy of Medical Sciences of Bosnia and Herzegovina - Medical Archives, Materia Socio-Medica and Acta Informatica Medica. Material and Methods: The research presents a meta-analysis of three journals, or their issues, during the calendar year 2015 (retrospective and descriptive character). Results: During 2015 calendar year a total of 286 articles were published (in Medical Archives 104 (36.3%), in Materia Socio-Medica 99 (34.6%), and in Acta Informatica Medica 83 (29%)). Original articles are present in the highest number in all three journals (in Medical Archives 80.7%, in Materia Socio Medica 77.7%, and in Acta Informatica Medica 68.6%). In Medical Archives, 90.3% of the articles were related to the field of clinical medicine. In Materia Socio-Medica, the domain of clinical medicine and public health was the most represented. Preclinical areas are most frequent in Acta Informatica Medica. The period of 50-60 days for a decision on the admission of article is most common in all three journals, with trend of shortening of that period. Articles came from 19 countries, mostly from Bosnia and Herzegovina, then from Iran, Kosovo, Saudi Arabia and Greece. Conclusion: In Medical Archives original articles in the field of clinical medicine (usually internal and surgical disciplines) are most often present, and that is the case in last four years. The number of articles in Materia Socio-Medica and Acta Informatica Medica is growing from year to year. In Materia Socio-Medica there is a

  7. Re-refinement of 4xan: hen egg-white lysozyme with carboplatin in sodium bromide solution

    PubMed Central

    Tanley, Simon W. M.; Schreurs, Antoine M. M.; Kroon-Batenburg, Loes M. J.; Helliwell, John R.

    2016-01-01

    A re-refinement of 4xan, hen egg-white lysozyme (HEWL) with carboplatin crystallized in NaBr solution, has been made and is published here as an addendum to Tanley et al. [(2014), Acta Cryst. F70, 1135–1142]. This follows a previous re-refinement and PDB deposition (4yem) by Shabalin et al. [(2015), Acta Cryst. D71, 1965–1979]. The critical evaluation of the original PDB deposition (4xan), and the subsequent critical examination of the re-refined structure (4yem), has led to an improved model (PDB code 5hmj). PMID:26919531

  8. An In Vivo Selection Identifies Listeria monocytogenes Genes Required to Sense the Intracellular Environment and Activate Virulence Factor Expression

    PubMed Central

    Portnoy, Daniel A.

    2016-01-01

    Listeria monocytogenes is an environmental saprophyte and facultative intracellular bacterial pathogen with a well-defined life-cycle that involves escape from a phagosome, rapid cytosolic growth, and ActA-dependent cell-to-cell spread, all of which are dependent on the master transcriptional regulator PrfA. The environmental cues that lead to temporal and spatial control of L. monocytogenes virulence gene expression are poorly understood. In this study, we took advantage of the robust up-regulation of ActA that occurs intracellularly and expressed Cre recombinase from the actA promoter and 5’ untranslated region in a strain in which loxP sites flanked essential genes, so that activation of actA led to bacterial death. Upon screening for transposon mutants that survived intracellularly, six genes were identified as necessary for ActA expression. Strikingly, most of the genes, including gshF, spxA1, yjbH, and ohrA, are predicted to play important roles in bacterial redox regulation. The mutants identified in the genetic selection fell into three broad categories: (1) those that failed to reach the cytosolic compartment; (2) mutants that entered the cytosol, but failed to activate the master virulence regulator PrfA; and (3) mutants that entered the cytosol and activated transcription of actA, but failed to synthesize it. The identification of mutants defective in vacuolar escape suggests that up-regulation of ActA occurs in the host cytosol and not the vacuole. Moreover, these results provide evidence for two non-redundant cytosolic cues; the first results in allosteric activation of PrfA via increased glutathione levels and transcriptional activation of actA while the second results in translational activation of actA and requires yjbH. Although the precise host cues have not yet been identified, we suggest that intracellular redox stress occurs as a consequence of both host and pathogen remodeling their metabolism upon infection. PMID:27414028

  9. An In Vivo Selection Identifies Listeria monocytogenes Genes Required to Sense the Intracellular Environment and Activate Virulence Factor Expression.

    PubMed

    Reniere, Michelle L; Whiteley, Aaron T; Portnoy, Daniel A

    2016-07-01

    Listeria monocytogenes is an environmental saprophyte and facultative intracellular bacterial pathogen with a well-defined life-cycle that involves escape from a phagosome, rapid cytosolic growth, and ActA-dependent cell-to-cell spread, all of which are dependent on the master transcriptional regulator PrfA. The environmental cues that lead to temporal and spatial control of L. monocytogenes virulence gene expression are poorly understood. In this study, we took advantage of the robust up-regulation of ActA that occurs intracellularly and expressed Cre recombinase from the actA promoter and 5' untranslated region in a strain in which loxP sites flanked essential genes, so that activation of actA led to bacterial death. Upon screening for transposon mutants that survived intracellularly, six genes were identified as necessary for ActA expression. Strikingly, most of the genes, including gshF, spxA1, yjbH, and ohrA, are predicted to play important roles in bacterial redox regulation. The mutants identified in the genetic selection fell into three broad categories: (1) those that failed to reach the cytosolic compartment; (2) mutants that entered the cytosol, but failed to activate the master virulence regulator PrfA; and (3) mutants that entered the cytosol and activated transcription of actA, but failed to synthesize it. The identification of mutants defective in vacuolar escape suggests that up-regulation of ActA occurs in the host cytosol and not the vacuole. Moreover, these results provide evidence for two non-redundant cytosolic cues; the first results in allosteric activation of PrfA via increased glutathione levels and transcriptional activation of actA while the second results in translational activation of actA and requires yjbH. Although the precise host cues have not yet been identified, we suggest that intracellular redox stress occurs as a consequence of both host and pathogen remodeling their metabolism upon infection. PMID:27414028

  10. A atuação do Observatório Nacional registrada nos relatórios ministeriais 1889 a 1930

    NASA Astrophysics Data System (ADS)

    Rodrigues, T.

    2003-08-01

    O período republicano até 1930 foi marcante na história do Observatório Nacional. Diversas reformas levaram a instituição a três ministérios diferentes e mudaram a ênfase do seu trabalho. A tão aguardada mudança para uma nova sede, em São Cristóvão, em 1920, não foi suficiente para que a instituição acompanhasse o ritmo tomado pela astronomia no mundo e se firmasse como ambiente de pesquisa. Uma análise simplificada poderia caracterizar um período de produção científica insignificante, dado o distanciamento da instituição dos novos rumos da astrofísica e da rápida inovação dos instrumentos, além do pequeno volume de publicações. Era uma época em que ainda não existiam os mecanismos formais de apoio e avaliação da atividade científica. Esse trabalho procura identificar a real atividade do Observatório no conteúdo dos Relatórios Ministeriais que, ao final de cada ano, apresentava as atividades, sucessos e problemas enfrentados pela instituição. Questões como instrumental e recursos humanos necessários; entraves burocráticos e financeiros; e articulações com outros observatórios se complementaram entre si ao longo desses anos para definir o perfil institucional e alguns aspectos fundamentais para a construção da astronomia no país. É possível concluir que a ênfase em serviços geográficos e de meteorologia, ao lado da inadequação dos instrumentos e do local, quase fizeram desaparecer a pesquisa em astronomia. Porém, vale destacar a sobrevivência de alguns trabalhos, como, por exemplo, variação de latitude e observação de estrelas duplas que mantiveram importante intercâmbio com outros grupos de pesquisa, demonstrando o constante esforço dos astrônomos e das diretorias em defesa da atividade científica.

  11. Análise sobre o Conhecimento de um Grupo de Alunos do Ensino Médio da Rede Estadual de São Paulo sobre Termos e Fenômenos Astronômicos do Cotidiano

    NASA Astrophysics Data System (ADS)

    de Oliveira, E. F.; Voelzke, M. R.; Amaral, L. H.

    2007-08-01

    Embora os Parâmetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as orientações complementares a esses Parâmetros (PCN+) apontem a importância de uma abordagem significativa de conceitos relacionados à astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano. Este trabalho tem por objetivo analisar os conhecimentos básicos em astronomia dos alunos de EM da escola estadual Batista Renzi, bem como investigar os meios através dos quais estes conhecimentos foram adquiridos. Para tanto foi elaborado um questionário de múltipla escolha aplicado a 310 alunos distribuídos entre as três séries do EM dos períodos matutino e noturno. Dessa forma, observou-se que apenas 34,5% relacionaram as estações do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influência gravitacional da Lua e do Sol como responsáveis pelo fenômeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distância e 34,2% reconheceram uma estrela cadente como meteoro. Em contrapartida, 67,1% compreendiam a sucessão entre dia e noite, 73,9% identificaram o Sol como estrela e 52,3% relacionaram o Big Bang à origem do Universo. Além disso, foram comparadas as respostas de alunos de diferentes séries e períodos, observando-se, dentre outras coisas, que os estudantes do terceiro ano apresentam um percentual de acertos semelhante ao dos alunos do primeiro, caracterizando que a abordagem de tópicos relacionados à astronomia no EM não tem contribuído para uma maior compreensão dos fenômenos e conceitos.

  12. Usina de ciências: um espaço pedagógico para aprendizagens múltiplas

    NASA Astrophysics Data System (ADS)

    Martin, V. A. F.; Poppe, P. C. R.; Orrico, A. C. P.; Pereira, M. G.

    2003-08-01

    Entendemos que o Ensino de Astronomia é especialmente apropriado para motivar os alunos e aprofundar conteúdos em diversas áreas do conhecimento, pois envolve temas ligados à Física, Matemática, Química, Computação, Tratamento de Imagens e Instrumentação de Alta Precisão, além daqueles pertinentes as áreas de Geografia, História e Antropologia. Contudo, apesar do caráter interdisciplinar que esta ciência possui, a realidade atual é que a maioria dos professores em sala de aula não foram devidamente capacitados, durante o período de formação acadêmica, para ministrar conteúdos de Astronomia nos atuais Ensinos Fundamental e Médio. Neste trabalho, discutiremos de maneira ampla, num primeiro momento, a realidade do atual ensino de ciências praticado no Estado da Bahia, apontando por dependência administrativa, o crescimento e a redução do número de escolas, da taxa de analfabetismo por faixa etária, da escolarização, do atendimento, da aprovação, reprovação e abandono, de equipamentos e laboratórios e o grau de formação dos nossos atuais professores em pleno exercício de atividade docente. Num segundo momento, discutiremos o papel do Observatório Astronômico Antares/UEFS dentro desse contexto, ou seja, suas ações implementadas ao longo dos últimos anos e em particular, o recente projeto de extensão Ensino e Difusão de Astronomia, financiado pela Fundação Vitae, que procura traduzir no lúdico, no brincar de ciências, um espaço pedagógico para aprendizagens múltiplas. Neste, o papel do professor multiplicador associado ao laboratório de kits didáticos, de fácil construção e manipulação (alguns dos quais serão mostrados), perfazem os principais veículos para o desenvolvimento de conhecimentos, atitudes, habilidades e valores que preparam os nossos alunos para a carreira técnico-científica e para sua participação crítica e criativa na Sociedade.

  13. Education or Reputation? A Look at America's Top-Ranked Liberal Arts Colleges

    ERIC Educational Resources Information Center

    Poliakoff, Michael; Alacbay, Armand

    2014-01-01

    ACTA [American Council of Trustees and Alumni] today released a report that examines the country's most prestigious liberal arts colleges. Despite endowments soaring as high as $1.8 billion, nearly all institutions increased tuition during the Great Recession to finance bloated administrative spending, with many college presidents enjoying…

  14. Experiences of a local arrangement committee for a large scientific conference

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper is an an invited condensation of a paper that appeared in Acta. Hort. 745: 513-532 last year. It describes the history and organization of the combined meeting of the 90th Annual Meeting of the Potato Association of America, the VI International Solanaceae Conference, and the III Solanace...

  15. Erratum to: Vascular endothelial growth factor induces contralesional corticobulbar plasticity and functional neurological recovery in the ischemic brain.

    PubMed

    Reitmeir, Raluca; Kilic, Ertugrul; Reinboth, Barbara S; Guo, Zeyun; ElAli, Ayman; Zechariah, Anil; Kilic, Ülkan; Hermann, Dirk M

    2015-10-01

    Erratum to: Acta Neuropathol (2012) 123:273–284. DOI 10.1007/s00401‑011‑0914‑z. The authors would like to correct Fig. 3 of the original manuscript, since the image in Fig. 3b does not correspond to a VEGF treated animal. Corrected Fig. 3 is shown below. We apologize for this mistake. PMID:26341346

  16. Extension of working range in Zeeman graphite furnace atomic absorption spectrometry by nonlinear calibration with prior correction for stray light

    NASA Astrophysics Data System (ADS)

    Lonardo, Robert F.; Yuzefovsky, Alexander I.; Zhou, Jack X.; McCaffrey, John T.; Michel, Robert G.

    1996-09-01

    The nonlinear working range of a Perkin-Elmer 4100Zl atomic absorption spectrometer was improved in three steps. Firstly, each absorbance datum within the transient profile was corrected for the presence of stray light by an algorithm originally developed by L'vov and co-workers (Spectrochim. Acta Part B, 47 (1992) 889-895 and 1187-1202), but with the incorporation of the Newton method of successive approximations (Spectrochim. Acta Part B, 49 (1994) 1643-1656. Secondly, a dip correction procedure was performed on temporal signal profiles that exhibited a dip due to rollover. In the final step, an analytically useful working curve was generated by the nonlinear calibration routine of Barnett (Spectrochim. Acta Part B, 39 (1984) 829). Goodness of fit between the resultant calibration curve and the data was measured by the method suggested by Miller-Ihli et al. (Spectrochim. Acta Part B, 39 (1984) 1603) that is based on the sum of squares of the percentage deviation (SSPD) and the root mean square (RMS) percentage deviation. For lead, silver, copper, thallium, and cadmium, the analytical nonlinear working range was increased by as much as one and a half orders of magnitude, without any significant effect on the RMS. For chromium and manganese, no significant improvement in the nonlinear working range was observed, while the RMS improved by 50%. In the case of nickel, neither the working range nor the RMS was improved.

  17. Eventos de Agosto (August Events).

    ERIC Educational Resources Information Center

    Toro, Leonor; Pla, Myrna

    Written in Spanish, this booklet contains brief information on seven August events celebrated by Puerto Ricans: Herbert Hoover's birthdate (August 10); Acta del Seguro Social (Social Security Act, August 14); Julian E. Blanco (August 14), Enmienda 19 Sufragia de la Mujer (Amendment 19, Women's Suffrage, August 26); Benjamin Harrison (August 20);…

  18. Intradistrict Resource Allocation: Key Findings and Policy Implications

    ERIC Educational Resources Information Center

    Houck, Eric A.

    2011-01-01

    The focus on school-level performance brought about by the No Child Left Behind Act--as well as recent court cases challenging the use of race in student assignment policies--has brought greater attention to the need to for careful study of the allocation of resources within school districts. This paper describes the policy context, reviews key…

  19. Nebraska Swims Hard against Testing's Tides

    ERIC Educational Resources Information Center

    Borja, Rhea R.

    2007-01-01

    Sometimes assessments that work in theory fall apart in reality. This article discusses the unique learning-measurement system in Nebraska. Instead of relying on statewide standardized tests to comply with the accountability requirements of the federal No Child Left Behind Act--as is the case in the other 49 states--districts in Nebraska use their…

  20. Antimicrobial resistance of Listeria monocytogenes isolated from a poultry further processing plant

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to compare antimicrobial resistance profiles of distinct types of Listeria monocytogenes isolated from a commercial poultry cooking plant. One hundred fifty seven L. monocytogenes isolates representing 14 different ActA types were tested for susceptibility to 19 ant...

  1. The Cost of Chaos in the Curriculum. Perspectives on Higher Education

    ERIC Educational Resources Information Center

    Capaldi Phillips, Elizabeth D.; Poliakoff, Michael B.

    2015-01-01

    ACTA's report "The Cost of Chaos in the Curriculum" reveals that the vast array of course choices given to college students is a cause of exploding costs and poor academic outcomes. And a bloated undergraduate curriculum is particularly detrimental to the success of students from lower socioeconomic backgrounds. The report documents how…

  2. Diffusive Insights: On the Disagreement of Christian Bohr and August Krogh at the Centennial of the Seven Little Devils

    ERIC Educational Resources Information Center

    Gjedde, Albert

    2010-01-01

    The year 2010 is the centennial of the publication of the "Seven Little Devils" in the predecessor of "Acta Physiologica". In these seven papers, August and Marie Krogh sought to refute Christian Bohr's theory that oxygen diffusion from the lungs to the circulation is not entirely passive but rather facilitated by a specific cellular activity…

  3. Investigating Multitasking in High-Functioning Adolescents with Autism Spectrum Disorders Using the Virtual Errands Task

    ERIC Educational Resources Information Center

    Rajendran, Gnanathusharan; Law, Anna S.; Logie, Robert H.; van der Meulen, Marian; Fraser, Diane; Corley, Martin

    2011-01-01

    Using a modified version of the Virtual Errands Task (VET; McGeorge et al. in "Presence-Teleop Virtual Environ" 10(4):375-383, 2001), we investigated the executive ability of multitasking in 18 high-functioning adolescents with ASD and 18 typically developing adolescents. The VET requires multitasking (Law et al. in "Acta Psychol" 122(1):27-44,…

  4. Prepared in Mind and Resources? A Report on Public Higher Education in South Carolina

    ERIC Educational Resources Information Center

    Alacbay, Armand; Poliakoff, Michael

    2011-01-01

    In 2011, South Carolina Governor Nikki Haley signed into law the South Carolina Higher Education Efficiency and Administrative Policies Act, maintaining the transparency and accountability that lead to increased academic quality and affordability at colleges and universities. It is in this context that ACTA (American Council of Trustees and…

  5. Measures of Muscular Strength in U.S. Children and Adolescents, 2012

    MedlinePlus

    ... performance and DXA-derived lean body mass and fat mass in pre-pubertal children. Acta Pædiatr 100(10):1359–67. 2011. Suggested citation Ervin RB, Wang C-Y, Fryar CD, et al. Measures of ...

  6. SPR Biosensor for the Detection of L. monocytogenes using Phage Displayed Antibody

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whole cells of Listeria monocytogenes were detected with a compact, surface plasmon resonance (SPR) sensor using a phage-displayed scFv antibody to the virulence factor ActA for biorecognition. Phage Lm P4:A8, expressing the scFv antibody fused to the pIII surface protein was immobilized to the se...

  7. Governance for a New Era: A Blueprint for Higher Education Trustees

    ERIC Educational Resources Information Center

    Schmidt, Benno C.

    2014-01-01

    "Governance for a New Era: A Blueprint for Higher Education Governance," is the product of a summit facilitated by ACTA [American Council of Trustees and Alumni] and chaired by Benno Schmidt, City University of New York Board chairman. Signatories to the statement, a diverse group of 22 distinguished national leaders, include college…

  8. Bold Leadership Real Reform [Annual Report, 2014

    ERIC Educational Resources Information Center

    American Council of Trustees and Alumni, 2015

    2015-01-01

    Higher education has never been more "front and center"--almost daily we hear about spiraling costs, the lack of academic rigor, and the stifling political correctness on our college campuses. Long before such issues were hot, ACTA [American Council of Trustees and Alumni] was already pointing out these worrisome trends and calling on…

  9. BIOGEOCHEMICAL CONTROLS ON REACTION OF SEDIMENTARY ORGANIC MATTER AND AQUEOUS SULFIDES IN HOLOCENE SEDIMENTS OF MUD LAKE FLORIDA: JOURNAL ARTICLE

    EPA Science Inventory

    JOURNAL NRMRL-ADA-00133 Filley,T.R., Freeman, K.H., Wilkin*, R.T., and Hatcher, P.G. Biogeochemical Controls on Reaction of Sedimentary Organic Matter and Aqueous Sulfides in Holocene Sediments of Mud Lake Florida. Geochimica et Cosmochimica Acta 66 (6):937-954...

  10. Development of Guidance for States Transitioning to New Safety Analysis Tools

    ERIC Educational Resources Information Center

    Alluri, Priyanka

    2010-01-01

    With about 125 people dying on US roads each day, the US Department of Transportation heightened the awareness of critical safety issues with the passage of SAFETEA-LU (Safe Accountable Flexible Efficient Transportation Equity Act--A Legacy for Users) legislation in 2005. The legislation required each of the states to develop a Strategic Highway…

  11. Polarization in RMnO3 multiferroics.

    PubMed

    Pirogov, A N

    2016-02-01

    Some comments on the review by Sim et al. [(2016). Acta Cryst. B72, 3-19] are given. The review is devoted to hexagonal multiferroics RMnO3, in which there are ferroelectric and magnetic orders. Strong interaction between these orders causes a series of interesting properties of multiferroics. PMID:26830791

  12. Activity Scale.

    ERIC Educational Resources Information Center

    Kerpelman, Larry C.; Weiner, Michael J.

    This twenty-four item scale assesses students' actual and desired political-social activism in terms of physical participation, communication activities, and information-gathering activities. About ten minutes are required to complete the instrument. The scale is divided into two subscales. The first twelve items (ACT-A) question respondents on…

  13. Higher: Setting a Higher Bar for Higher Ed. 2013 Annual Report

    ERIC Educational Resources Information Center

    American Council of Trustees and Alumni, 2014

    2014-01-01

    The American Council of Trustees and Alumni (ACTA) is leading the charge to return "higher" to higher education. We are challenging the status quo to restore academic freedom, academic rigor, and real accountability to higher education. And, we are doing so with an ever-widening network of supporters and partners.

  14. Magnus Strandqvist: 50th anniversary of his doctoral thesis.

    PubMed

    Kajanti, M J

    1994-01-01

    This article is dedicated to Magnus Strandqvist's famous doctoral thesis "Studien über die kumulative Wirkung der Röntgenstrahlen bei Fraktionierung. Erfahrungen aus dem Radiumhemmet an 280 Haut- und Lippenkarzinomen" published in Acta Radiologica in 1944. After a short biography of Strandqvist some central points of his work and their influence on future development of modern radiotherapy are presented. PMID:7993639

  15. Effects of space flights on human allergic status (IgE-mediated sensitivity)

    NASA Astrophysics Data System (ADS)

    Buravkova, L. B.; Rykova, M. P.; Gertsik, Y. G.; Antropova, E. N.

    2007-02-01

    Suppression of the immune system after space flights of different duration has been reported earlier by Konstantinova [Immune system in extreme conditions, Space immunology. B. 59. M. Science 1988. 289p. (in Russian) [4]; Immunoresistance of man in space flight, Acta Astronautica 23 (1991) 123-127 [5

  16. The Metalloprotease Mpl Supports Listeria monocytogenes Dissemination through Resolution of Membrane Protrusions into Vacuoles.

    PubMed

    Alvarez, Diego E; Agaisse, Hervé

    2016-06-01

    Listeria monocytogenes is an intracellular pathogen that disseminates within the intestinal epithelium through acquisition of actin-based motility and formation of plasma membrane protrusions that project into adjacent cells. The resolution of membrane protrusions into vacuoles from which the pathogen escapes results in bacterial spread from cell to cell. This dissemination process relies on the mlp-actA-plcB operon, which encodes ActA, a bacterial nucleation-promoting factor that mediates actin-based motility, and PlcB, a phospholipase that mediates vacuole escape. Here we investigated the role of the metalloprotease Mpl in the dissemination process. In agreement with previous findings showing that Mpl is required for PlcB activation, infection of epithelial cells with the ΔplcB or Δmpl strains resulted in the formation of small infection foci. As expected, the ΔplcB strain displayed a strong defect in vacuole escape. However, the Δmpl strain showed an unexpected defect in the resolution of protrusions into vacuoles, in addition to the expected but mild defect in vacuole escape. The Δmpl strain displayed increased levels of ActA on the bacterial surface in protrusions. We mapped an Mpl-dependent processing site in ActA between amino acid residues 207 to 238. Similar to the Δmpl strain, the ΔactA207-238 strain displayed increased levels of ActA on the bacterial surface in protrusions. Although the ΔactA207-238 strain displayed wild-type actin-based motility, it formed small infection foci and failed to resolve protrusions into vacuoles. We propose that, in addition to its role in PlcB processing and vacuole escape, the metalloprotease Mpl is required for ActA processing and protrusion resolution. PMID:27068088

  17. Obligatory course unit! Trainee astronomers learn to communicate their future scientific results

    NASA Astrophysics Data System (ADS)

    Del Puerto, C.

    2008-06-01

    A scientist must not only do science, but must also know how to communicate it. It is possible that he or she even ends up becoming devoted professionally either to outreach or to teaching. Therefore, the Master's Degree Course in Astrophysics, created by the University of La Laguna (ULL) with the collaboration of the Instituto de Astrofisica de Canarias (IAC), includes in its programme the four-month core course unit Communicating Astronomy: Professional Results and Educational Practice (in Spanish, Comunicación de Resultados Cientificos y Didactica de la Astronomia), that is worth three ECTs. In this poster, I present the results of our experience from the academic year 2006-2007, in which seventeen Master's students, in addition to learning the skills necessary to communicating their results within the scientific community, have also studied the language of popularisation in a practical and fun way through role-playing as science writers and schoolteachers in the classroom.

  18. Erratum: Observations and Atmospheric Parameters of Super-Metal-rich Candidates

    NASA Astrophysics Data System (ADS)

    Malagnini, M. L.; Morossi, C.; Buzzoni, A.; Chavez, M.

    2001-01-01

    In the paper ``Observations and Atmospheric Parameters of Super-Metal-rich Candidates'' by M. L. Malagnini, C. Morossi, A. Buzzoni, and M. Chavez (PASP, 112, 1455 [2000]), the affiliations for M. L. Malagnini and A. Buzzoni are incorrect in the print, PDF, and Postscript versions. The affiliations are correct in the HTML version. The correct affiliation for M. L. Malagnini is Dipartimento di Astronomia, Università degli Studi di Trieste, via G. B. Tiepolo 11, 34131 Trieste, Italy. The correct affiliations for A. Buzzoni are Osservatorio Astronomico di Brera, via Bianchi 46, 23807 Merate (Lc), Italy; and Telescopio Nazionale Galileo, Observatorio Roque de los Muchachos, A.P. 565, 38700 Santa Cruz de La Palma, Canary Islands, Spain. The Press sincerely regrets this error.

  19. Editorial

    NASA Astrophysics Data System (ADS)

    Bruzzi, Mara; Cartiglia, Nicolo; Pace, Emanuele; Talamonti, Cinzia

    2015-10-01

    The 10th edition of the International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices (RESMDD) was held in Florence, at Dipartimento di Fisica ed Astronomia on October 8-10, 2014. It has been aimed at discussing frontier research activities in several application fields as nuclear and particle physics, astrophysics, medical and solid-state physics. Main topics discussed in this conference concern performance of heavily irradiated silicon detectors, developments required for the luminosity upgrade of the Large Hadron Collider (HL-LHC), ultra-fast silicon detectors design and manufacturing, high-band gap semiconductor detectors, novel semiconductor-based devices for medical applications, radiation damage issues in semiconductors and related radiation-hardening technologies.

  20. Kepler's winding Path to true Heliocentrism

    NASA Astrophysics Data System (ADS)

    Bialas, Volker

    The paper concerns the evolution of concepts by Johannes Kepler from Aristotelian conception of the Universe to Heliocentrism. Already as young Magister in Tubingen Kepler has taken an active part in Physical disputations of the candidates and has defended the doctrines of Copernik (1). In the Mysterium Cosmographicum he refers the planetary distances no longer to the center of the earth's orbit, but to the center of the true sun. But just by working out his Astronomia Nova Kepler succeeds in creating a strictly heliocentric astronomy as his handwriting Manuscripts give detailed information (2). Notes: 1) fragmentum orations de motu terrae. In Keppler Gesammelte werke Vol. 20.1, Munich 1988, p. 147-149 2) Commentaria in Theoriam Martis. Edition in: Kepler Gessamelete Werke Vol. 20.2 (in preparation)

  1. An eighteenth century travelling theodolite.

    PubMed

    Malaquias, Isabel

    2016-01-01

    An old topographic compass displayed in a showroom of the Museu de Astronomia e Ciências Afins (MAST), in Rio de Janeiro, Brazil, took our curiosity namely because of its resemblance to a theodolite, described by J.H. de Magellan. Not many things were known about its previous history. From the different documents studied, and the characteristics of this singular theodolite, it must have belonged to the collections of instruments acquired for the Brazilian border demarcations undertaken after the Santo Ildefonso Treaty, agreed to by the Portuguese and Spanish courts in 1777. Several instruments were bought in London, and supervised and chosen by Magellan, the Portuguese instruments expert. We present arguments in favour of this conclusion. PMID:27557355

  2. Percepção astronómica de um grupo de alunos do ensino médio de uma escola da rede estadual de São Paulo

    NASA Astrophysics Data System (ADS)

    de Oliveria, E. F.; Voelzke, M. R.

    2009-03-01

    Sendo a Astronomia uma das cièncias mais antigas da humanidade, e considerando sua importáncia histórica e cultural, é de extrema releváncia que tópicos relacionados a ela sejam tratados nas escolas. Embora os Parámetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as Orientaçiacute;es Complementares aos Parámetros (PCN+) apontem a importáncia de uma abordagem significativa de conceitos relacionados à Astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano e sejam alvos da curiosidade natural dos jovens. Da observação dessa curiosidade em alunos de uma escola pública paulista, na cidade de Suzano, surgiu o interesse em investigar os conhecimentos básicos em Astronomia dos alunos do Ensino Médio desta escola, constituindo-se este como principal objetivo desta pesquisa. Para tanto foi elaborado um questionário de múltipla escolha aplicado inicialmente a 34 alunos do primeiro ano e, posteriormente, a mais 310, distribuídos entre as très séries do Ensino Médio dos períodos matutino e noturno. Dessa forma, observou-se que 73,9% dos estudantes identificaram o Sol como sendo uma estrela, 67,1% mostraram compreender a sucessão entre dia e noite e 52,3% relacionaram o Big Bang à origem do Universo. Em contrapartida, apenas 34,5% relacionaram as estaçíes do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influència gravitacional simultánea da Lua e do Sol como responsável pelo fenòmeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distáncia e 34,2% reconheceram as estrelas cadentes como meteoros, evidenciando-se assim o pequeno discernimento dos estudantes quanto aos fenòmenos e termos astronòmicos do cotidiano. Além disso, foram comparadas as respostas de alun! os de diferentes s

  3. Astronomy Week in Madeira, Portugal

    NASA Astrophysics Data System (ADS)

    Augusto, P.; Sobrinho, J. L.

    2012-05-01

    The outreach programme Semanas da Astronomia (Astronomy Weeks) is held in late spring or summer on the island of Madeira, Portugal. This programme has been attracting enough interest to be mentioned in the regional press/TV/radio every year and is now, without doubt, the astronomical highlight of the year on Madeira. We believe that this programme is a good case study for showing how to attract the general public to astronomy in a small (population 250 000, area 900 km2) and fairly isolated place such as Madeira. Our Astronomy Weeks have been different each year and have so far included exhibitions, courses, talks, a forum, documentaries, observing sessions (some with blackouts), music and an astro party. These efforts may contribute towards putting Madeira on the map with respect to observational astronomy, and have also contributed to the planned installation of two observatories in the island.

  4. New large outburst of 29P/Schwassmann-Wachmann 1

    NASA Astrophysics Data System (ADS)

    Kidger, Mark

    2010-04-01

    Mark Kidger reports on behalf of the "Observadores_cometas Group" that a major new outburst of Comet 29P/Schwassmann-Wachmann has occurred two days before the Herschel Space Observatory is due to observe the comet. The outburst was first reported on 2010 Apr. 16, 19:22UT at R=12.8 in a 10" square aperture by Estevé Cortés and the Grup d'Astronomia de Mataró (MPC A06, Mataró, Spain), having been last seen at R=16.18 by José Ramón Vidal (MPC 945, Gijón, Spain) on 2010 Apr.

  5. New Archiving Distributed InfrastructuRe (NADIR): Status and Evolution

    NASA Astrophysics Data System (ADS)

    De Marco, M.; Knapic, C.; Smareglia, R.

    2015-09-01

    The New Archiving Distributed InfrastructuRe (NADIR) has been developed at INAF-OATs IA2 (Italian National Institute for Astrophysics - Astronomical Observatory of Trieste, Italian center of Astronomical Archives), as an evolution of the previous archiving and distribution system, used on several telescopes (LBT, TNG, Asiago, etc.) to improve performance, efficiency and reliability. At the present, NADIR system is running on LBT telescope and Vespa (Italian telescopes network for outreach) Ramella et al. (2014), and will be used on TNG, Asiago and IRA (Istituto Radio Astronomia) archives of Medicina, Noto and SRT radio telescopes Zanichelli et al. (2014) as the data models for radio data will be ready. This paper will discuss the progress status, the architectural choices and the solutions adopted, during the development and the commissioning phase of the project. A special attention will be given to the LBT case, due to some critical aspect of data flow and policies and standards compliance, adopted by the LBT organization.

  6. [Peter of Abano, the 'Conciliator' between magic and science].

    PubMed

    Federici Vescovini, Graziella

    2008-01-01

    Peter of Abano is a personage belonging to history as well as to legend. In this analysis his historical physiognomy of scientist and physician is reconstructed on the basis of a better knowledge of his works in medicine and astronomy (now edited), a discipline, the latest one, in which he excelled in Medieval scientific context (The Lucidator dubitabilium astronomiae (astrologiae) can be read in the critical edition by G. Federici Vescovini, Padova, Esedra, 1992). He opposed extreme position in all fields, by styling himself 'Conciliator' of opposed tendencies. He often reconfirmed a rational concept of medicine and astronomy, which dispelled any demoniac and magic features, against the fanciful legend elaborated during the following centuries. PMID:19831246

  7. [SCIENCE AND DREAMS IN THE MIDDLE AGES: IL "DE SOMNIIS" DI BOEZIO DI DACIA].

    PubMed

    Feti, Viola

    2015-01-01

    Boethius of Dacia's opera "De somnis" can be defined as a brief treaty that partially follows the traditional quaestio scheme. It includes a passage that seems to copy Etienne Tempier's proposition number sixty-five, which condemns the importance attributed to astrology by many medieval authors. Boethius moves off Aristotle's "De somno et vigilia" idea of physiological dreams to assert a new kind of oneiric phenomena linked to constellations, that, according to the author, aren't divinely inspired, whereas they are to be considered as natural events. Boethius isn't the only philosopher who writes about this particular type of dream as another medieval author, Albertus Magnus, in his "Speculum Astronomiae", describes astrology and its relationship to medicine. PMID:26946816

  8. The Transits of Venus and New Technologies: A Time to Reflect

    NASA Astrophysics Data System (ADS)

    Brashear, Ron

    2005-01-01

    In the recent history of astronomy there have been occasions where `New Astronomies' have been introduced. In the spirit of the recent excitement of the 2004 transit of Venus, I have used the periods around the historical transits to reflect on the `New Astronomies' of those eras. Johannes Kepler's Astronomia Nova is a fine representation of the New Astronomy of the 1631-1639 transit pair and Pierre Simon, Marquis de Laplace's Traité de Mécanique Céleste reflects the New Astronomy of the 1761-1769 transit pair. A combination of Samuel P. Langley's The New Astronomy and James E. Keeler's 1897 paper on astrophysics have been chosen as the exemplars of the New Astronomy of the 1874-1882 transit pair. I am open to suggestions for the works that best represent the 2004-2012 transit pairs.

  9. Stubborn Mars is in search of a domicile. Johannes Kepler to Christian II. elector of Saxony - a rediscovery. (German Title: Der halsstarrige Mars sucht sich eine Wohnung. Johannes Kepler an Kurfürst Christian II. von Sachsen - Eine Wiederentdeckung)

    NASA Astrophysics Data System (ADS)

    Kothmann, Hella

    2011-08-01

    The rediscovery of a missing autograph of Johannes Kepler - a dedication letter presenting his "New Astronomy" to the elector of Saxony - was possible through a series of fortunate coincidences. Kepler's most important work "Astronomia Nova", in which he proclaimed the first two planetary laws, has been published at the end of 1609. According to the Latin dedication to emperor Rudolf II., Kepler compares the long period of calculations and observations as a crusade against the planet Mars. Finally he succeeds in defeating him, now he supports his opponent to find a new home. The letter is an extraordinary document of Kepler's ingenious and humorous language, it also proofs the relationship to Dresden and the Saxon court.

  10. Perspectivas Futuras para o Observatório do Pico dos Dias

    NASA Astrophysics Data System (ADS)

    Bruch, Albert

    2004-02-01

    Com o Observatório Gemini plenamente operacional e o telescópio SOAR iniciando suas operações em breve, a astronomia observacional brasileira encontra-se no auge de uma transformação profunda que terá um impacto grave no Observatório do Pico dos Dias - OPD. Refletimos aqui sobre a natureza desse impacto e estratégias para manter a competitividade do OPD. Não queremos apresentar receitas prontas, mas idéias que poderão servir como base de discussão sobre o uso inteligente dos telescópios do OPD como parte do conjunto de instrumentos disponíveis à comunidade astronômica brasileira.

  11. Visits to La Plata Observatory

    NASA Astrophysics Data System (ADS)

    Feinstein, A.

    1985-03-01

    La Plata Observatory will welcome visitors to ESO-La Silla that are willing to make a stop at Buenos Aires on their trip to Chile or on their way back. There is a nice guesthouse at the Observatory that can be used, for a couple of days or so, by astronomers interested in visiting the Observatory and delivering talks on their research work to the Argentine colleagues. No payments can, however, be made at present. La Plata is at 60 km from Buenos Aires. In the same area lie the Instituto de Astronomia y Fisica dei Espacio (IAFE), in Buenos Aires proper, and the Instituto Argentino de Radioastronomia (IAR). about 40 km from Buenos Aires on the way to La Plata. Those interested should contacl: Sr Decano Prof. Cesar A. Mondinalli, or Dr Alejandro Feinstein, Observatorio Astron6mico, Paseo dei Bosque, 1900 La Plata, Argentina. Telex: 31216 CESLA AR.

  12. Heralds of Astronomy: Landmark Works in the History of Astronomy.

    NASA Astrophysics Data System (ADS)

    Brashear, R.

    2001-12-01

    In 1955, the famous science book collector Bern Dibner published his classic work, Heralds of Science, a description of two hundred books from his collection that marked great moments in the development of the sciences and technology. He included seventeen astronomy titles, from early works such as Regiomontanus's Epitome of Ptolemy (1496), Copernicus's On the Revolutions of the Heavenly Spheres (1543), and Kepler's Astronomia Nova (1609), up to Herschel's "Account of a Comet" (1782), Laplace's Treatise on Celestial Mechanics (1798-1825), and Adams's paper leading to the discovery of Neptune (1846). This talk will take a closer look at the works and their authors, as well as their relevance for historical research in the future. Given time, there will be some discussion on the possibility of collecting these works for your own library, and why many other works were not on Dibner's list.

  13. Thermal gradient analysis for the ESOPO spectrograph

    NASA Astrophysics Data System (ADS)

    Farah, A.; González, J. Jesús; Sierra, G.; Hernández, J. V.; Pedrayes, M.; Echevarría, J.; Costero, R.; Avila, G.; Arroyo, M.; Cobos, F.; Colorado, E.; Cordova, A.; Chapa, O.; Garcia, B.; Garfias, F.; Granados, F.; Guisa, G.; Luna, E.; Martínez, B.; Michel, R.; Murillo, F.; Pérez, F.; Quechol, S.; Quirós, F.; Tejada, C.

    2008-07-01

    ESOPO will be a spectrograph of medium resolution for the 2.1 m telescope of the National Observatory at San Pedro Martir, Baja California, Mexico. It has been developed by the Instituto de Astronomia of the Universidad Nacional Autonoma de Mexico (IA-UNAM). The main goal of this instrument is to modernize the capabilities of making science with that particular telescope. It is planned to achieve a spectral resolution between 500 and 5000. ESOPO is split into two arms; each one specialized in a specific wavelength range covering together all the visible light. A very important issue in spectrographs is to avoid inside thermal gradients. Different temperatures in the optical elements produce mechanical movements and image quality degradation during an exposition. The error budget analysis developed for ESOPO allows establishing the required limits for temperature gradients. In this paper is described the thermal analysis of the spectrograph, including specifications, finite element models, thermal equations and expected thermal gradients.

  14. Spacecraft Attitude and Orbit Control Systems testing

    NASA Astrophysics Data System (ADS)

    Sonnenschein, F. J.; Schoomade, M.; Zwartbol, T.

    1995-03-01

    Contemporary AOCS are equipped with local Attitude Control Computers which provide sophisticated Attitude and Orbit Control functions, automatic Failure Detection and Isolation functions and extensive Telemetry and Telecommand handling functions. Generic models of the design, development and test life cycle approaches for such intelligent AOCS are emerging. Also knowledge of the activities to be performed and the generic design, development and test environments to be used during the different phases is accumulating. Lessons learned can be used to improve AOCS development life cycle approaches and to define new development and test environments which improve the efficiency of the design, development and test life cycle and quality of the product. The SAX (Satellite per Astronomia a raggi X) satellite is equipped with a contemporary AOCS providing the above mentioned functions. In this paper the SAX AOCS software design, development and test life cycle is described as an example of AOCS software development. Lessons learned and suggestions for possible improvements are given.

  15. [Carlos Chagas Filho: an articulator of the history of sciences in Brazil].

    PubMed

    Domingues, Heloisa Maria Bertol

    2012-06-01

    A letter sent in 1982 by a group of scientists to the president of Conselho Nacional de Desenvolvimento Científico e Tecnológico appealed for a policy of preservation of Brazilian scientific culture. The name of Carlos Chagas Filho topped the list of signatures thereby proving his commitment to that proposal, the ideological structure of which was part of his experience in scientific policy in Brazil and abroad. This document harks back to the practice of the history of the sciences in Brazil and the creation of places for the safeguard and organization of scientific memory, such as the Museu de Astronomia e Ciências Afins, Casa de Oswaldo Cruz and the Sociedade Brasileira de História da Ciência, of which Carlos Chagas Filho was an inaugural member of the board of directors. PMID:22473448

  16. The commissioning instrument for the Gran Telescopio Canarias: made in Mexico

    NASA Astrophysics Data System (ADS)

    Cuevas, Salvador; Sánchez, Beatriz; Bringas, Vicente; Espejo, Carlos; Flores, Rubén; Chapa, Oscar; Lara, Gerardo; Chavoya, Armando; Anguiano, Gustavo; Arciniega, Sadot; Dorantes, Ariel; Gonzalez, José L.; Montoya, Juan M.; Toral, Rafael; Hernández, Hugo; Nava, Roberto; Devaney, Nicolas; Castro, Javier; Cavaller, Luis; Farah, Alejandro; Godoy, Javier; Cobos, Francisco; Tejada, Carlos; Garfias, Fernando

    2006-02-01

    In March 2004 was accepted in the site of Gran Telescopio Canarias (GTC) in La Palma Island, Spain, the Commissioning Instrument (CI) for the GTC. During the GTC integration phase, the CI will be a diagnostic tool for performance verification. The CI features four operation modes-imaging, pupil imaging, Curvature Wave-front sensing (WFS), and high resolution Shack-Hartmann WFS. This instrument was built by the Instituto de Astronomia UNAM in Mexico City and the Centro de Ingenieria y Desarrollo Industrial (CIDESI) in Queretaro, Qro under a GRANTECAN contract after an international public bid. Some optical components were built by Centro de Investigaciones en Optica (CIO) in Leon Gto and the biggest mechanical parts were manufactured by Vatech in Morelia Mich. In this paper we made a general description of the CI and we relate how this instrument, build under international standards, was entirely made in Mexico.

  17. NASA Astrophysics Data System (ADS)

    Morisset, C.; Delgado-Inglada, G.; Torres-Peimbert, S.

    2014-04-01

    Most - if not all - planetary nebulae exhibit a complex structure, far from the spherical shape. The reasons for this dramatic change in symmetry, that occurs in early stage of the development of the nebula, remain controversial. The same physics operates in a variety of stars, from young (winds from young stars and/or high mass stars) to old (novae, symbiotic stars). The aim of the APN series of conferences has been to offer the opportunity to anyone involved in the study of asymmetric planetary nebulae (and related objects) to discuss the latest results obtained in this field. The APN VI conference was organized by the Instituto de Astronomia (UNAM) and took place on Riviera Maya, Quintana Roo, México, 4-8 Nov. 2013

  18. Tycho Brahe Censured

    NASA Astrophysics Data System (ADS)

    Lerner, Michel-Pierre

    The starting point of this paper is a harsh judgment on Brahe's religion pronounced in 1651 by the Jesuit astronomer Giambattista Riccioli. A recent discovery in the Vatican Archives of the ACDF explains partly this judgment. Riccioli knew of a consultation in 1620 by Cardinal Robert Bellarmine and of a decree of the Holy Office, registered but not published, concerning the Astronomiae instauratae Progymnasmata (Uraniburgi Daniae - Pragae Bohemiae M.DC.II). This unpublished censure - Brahe was never condemned in the Roman Indexes - circulated in the Jesuit milieux, and there are some copies of Brahe's book carrying names and praises of heretics crossed out according to the decision of 1620. This paper considers too the important place officially reserved to Brahe in the Indexes published in Spain during the 17th century (and later).

  19. Bradley and Lacaille: Praxis as Passionate Pursuit of Exact Science

    NASA Astrophysics Data System (ADS)

    Wilson, C. A.

    1997-12-01

    From 1700 to 1800, astronomical observation and prediction improved in accuracy by an order of magnitude or more: by century's end astronomers could trust catalogued and predicted positions to within a few arcseconds. Crucial to this improvement were the discoveries of Bradley, which grew out of an endeavor of "normal science," the attempt to confirm with precision Robert Hooke's earlier supposed discovery of annual parallax in Gamma Draconis. On the theoretical side, Bradley's discoveries led to the quiet demise of two earlier doctrines, the Tychonic System and the Aristotelian and Cartesian doctrine of the instantaneous transmission of light. On the side of praxis, Bradley's discoveries meant that observational astronomy must be re-done from the ground up. In 1742 Nicolas-Louis Lacaille (1713-62), who had been admitted to the Paris Academie des Sciences only the year before, proposed to his astronomer colleagues that they take up this task as a cooperative enterprise. His proposal met with silence, but he undertook the project on his own, making it his life's work. By 1757 he had completed his Fundamenta Astronomiae, including a catalogue of 400 bright stars in which for the first time star positions were corrected for aberration and nutation. In 1758 he published his solar tables, the first to incorporate lunar and planetary perturbations as well as aberration and nutation. Lacaille's pendulum clock was not temperature-compensated, and his sextant poorly calibrated, but he was to some extent able to compensate for these flaws by bringing a massive number of observations to bear. Till the 1790s his Fundamenta Astronomiae and Tabulae Solares were important for the increments in accuracy they brought about, and for the inspiration they gave to later astronomers such as Delambre.

  20. Inclusion of Astronomy Themes in an Inovative Approach of Informal Physics Teaching for High School Students. (Spanish Title: Inclusión de Temas Astronómicos en Uma Abordaje Innovadora de la Enseñanza Informal de Física Para Estudiantes de Secumdaria.) Inclusão de Temas Astronômicos Numa Abordagem Inovadora do Ensino Informal de Física Para Estudantes do Ensino Médio

    NASA Astrophysics Data System (ADS)

    Tiara Mota, Aline; de Morais Bonomini, Iracema Ariel; Meloni Martins Rosado, Ricardo

    2009-12-01

    The current work reports on an experience on Astronomy education at the Federal University of Itajubá through an extra-curricular course offered for High School students. This initiative was motivated by the low attention paid to the Astronomy subjects at this stage of the Brazilian Formal Education, in spite that the National Curricular Parameters (PCN and PCN+, in Brazil) point out the importance of their inclusion Este artículo relata una experiencia en la enseñanza de la astronomía efectuada en la Universidad Federal de Itajubá en la forma de un curso de extensión orientado para los estudiantes del colegio secundario. Esta iniciativa surgió de constatar la poca atención dada a la Astronomía en esta etapa de la Educación formal brasileña, a pesar que los Parámetros Curriculares Nacionales (PCN y PCN+, en Brasil) destacan la importancia de su inclusión. Este artigo relata uma experiência em ensino de Astronomia realizada na Universidade Federal de Itajubá na forma de um curso de extensão voltado para alunos do Ensino Médio. Esta iniciativa surgiu da pouca atenção que se dá à Astronomia nesta etapa da Educação embora os Parâmetros Curriculares Nacionais (PCN e PCN+) apontem a importância de sua inclusão.

  1. A Concepção de Universo entre Alunos do Ensino Médio de São Paulo e suas Fontes de Aquisição

    NASA Astrophysics Data System (ADS)

    Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

    2006-08-01

    Nesse trabalho procurou-se identificar por meio de um questionário as concepções de Universo, de espaço e tempo que sustentam a visão de mundo de um grupo de 270 estudantes de Ensino Médio, pertencentes a três escolas de São Paulo. As questões relacionadas aos conhecimentos prévios dos estudantes permitiram constatar que há pouco conhecimento acerca dos temas investigados, destacando-se que apenas 20% dos alunos foram capazes de relacionar as semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo, verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% concebiam o Sol como uma estrela. No que se refere às fontes de aquisição que proporcionaram esses conhecimentos, apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de Ast! ronomia, verificou-se claramente que para a maioria dos alunos seus conceitos ainda são inadequados, havendo necessidade de aprimoramento da abordagem desses conteúdos, pois apesar de popular, a Astronomia ainda é veiculada de maneira pouco esclarecedora e com imprecisões. Nesse contexto, são discutidas algumas possíveis contribuições que podem ser dadas para o ensino de Astronomia pelo uso das ferramentas computacionais nas escolas.

  2. The First Two Years of the Latin-American Journal of Astronomy Education (relea)

    NASA Astrophysics Data System (ADS)

    Bretones, P. S.; Jafelice, L. C.; Horvath, J. E.

    2006-08-01

    We present and discuss in this work the motivations, goals and strategies adopted for its creation and launch of the e-journal LATIN-AMERICAN JOURNAL OF ASTRONOMY EDUCATION (RELEA). The RELEA "first light" was in August, 2004 with the appearance of No. 1 and it is now completing two years of existence. The creation of the new journal was prompted by: a) the noteworthy absence of a specific publication in the field in Latin-America; b) the lack of classroom material in Spanish/Portuguese that could be directly used without too many adaptations; and c) the need of a regional forum to discuss and suggest public policies concerning the teaching of Sciences in general and Astronomy in particular. We identify and present the difficulties encountered for the achievement of the proposed objectives and operational issues in this period, together with the adopted solutions (refereeing procedure, periodicity, etc.). Finally, we attempt to evaluate the long-run impact of such initiatives on the scientific education as a tool for effective citizenship decision making, so critical for Third-World countries. References Bretones, P.S., Jafelice, L.C. & Horvath, J.E. , 2004, Editorial of the RELEA No.1, available at (http://www.iscafaculdades.com.br/relea/). Bretones, P.S., Jafelice, L.C. & Horvath, J.E. , 2005, Editorial of the RELEA No.2, available at (http://www.iscafaculdades.com.br/relea/). Bretones, P.S., Jafelice, L.C. & Horvath, J.E., A Revista Latino-Americana de Educação em Astronomia: objetivos e estratégias. In: Encontro Brasileiro de Ensino de Astronomia, 8, 2004, São Paulo. Proceedings. (In press). [The Latin-American Journal of Astronomy Education: Objectives and Strategies. In: 8th Brazilian Meeting on Astronomy Teaching.

  3. Projeto observatórios virtuais: educação através de telescópios robóticos

    NASA Astrophysics Data System (ADS)

    Santana, P. H. S.; Shida, R. Y.

    2003-08-01

    O principal objetivo do projeto Observatórios Virtuais é o ensino na área de ciências através de atividades práticas desenvolvidas em colaboração entre instituições de pesquisa em astronomia e escolas de ensino médio e fundamental. Este ano deverá ser concluída a implantação do programa piloto de estudos, pesquisas e observação astronômica direta, com utilização em tempo real de telescópios robóticos, que assim funcionarão como "observatórios virtuais". O objetivo pedagógico das atividades práticas baseadas nas imagens atronômicas é desenvolver as habilidades e competências dos alunos no uso do método científico. Para isso, serão realizados projetos interdisciplinares, a partir de observações astronômicas, já que a astronomia é uma área interdisciplinar por excelência. Essas atividades terão níveis diferenciados de complexidade, que podem ser adequados aos vários graus do ensino e realidades regionais. Será dada ênfase ao desenvolvimento e aplicação em São Paulo, onde atua a equipe do IAG/USP. Como resultados apresentados no presente trabalho, temos a criação de um software em português para o processamento de imagens obtidas através de CCDs e a elaboração de material para as atividades educacionais relacionadas.

  4. Second monoclinic polymorph of 4-[(1H-benzimidazol-1-yl)meth­yl]benzoic acid

    PubMed Central

    Kuai, Hai-Wei; Cheng, Xiao-Chun

    2011-01-01

    Recently, we reported the first monoclinic [Kuai & Cheng (2011). Acta Cryst., E67, o2787] and the ortho­rhom­bic polymorph [Kuai & Cheng (2011). Acta Cryst., E67, o3014] of the title compound, C15H12N2O2. Another monoclinic polymorph was obtained accidentally by the hydro­thermal reaction of the title compound with manganese chloride in the presence of potassium hydroxide at 413 K. The asymmetric unit consists of four independent mol­ecules. In the crystal, O—H⋯N hydrogen bonds link the independent mol­ecules into four separate chains parallel to the b axis. PMID:22199726

  5. A Short History of Medical Informatics in Bosnia and Herzegovina

    PubMed Central

    Masic, Izet

    2014-01-01

    The health informatics profession in Bosnia and Herzegovina has relatively long history. Thirty five years from the introduction of the first automatic manipulation of data, thirty years from the establishment of Society for Medical Informatics BiH, twenty years from the establishment of the Scientific journal “Acta Informatica Medica (Acta Inform Med”, indexed in PubMed, PubMed Central Scopus, Embase, etc.), twenty years on from the establishment of the first Cathedra for Medical Informatics on Biomedical Faculties in Bosnia and Herzegovina, ten years on from the introduction of the method of “Distance learning” in medical curriculum. The author of this article is eager to mark the importance of the above mentioned Anniversaries in the development of Health informatics in Bosnia and Herzegovina and have attempted, very briefly, to present the most significant events and persons with essential roles throughout this period. PMID:24648621

  6. The spectral sensitivity of the human short-wavelength sensitive cones derived from thresholds and color matches.

    PubMed

    Stockman, A; Sharpe, L T; Fach, C

    1999-08-01

    We used two methods to estimate short-wave (S) cone spectral sensitivity. Firstly, we measured S-cone thresholds centrally and peripherally in five trichromats, and in three blue-cone monochromats, who lack functioning middle-wave (M) and long-wave (L) cones. Secondly, we analyzed standard color-matching data. Both methods yielded equivalent results, on the basis of which we propose new S-cone spectral sensitivity functions. At short and middle-wavelengths, our measurements are consistent with the color matching data of Stiles and Burch (1955, Optica Acta, 2, 168-181; 1959, Optica Acta, 6, 1-26), and other psychophysically measured functions, such as pi 3 (Stiles, 1953, Coloquio sobre problemas opticos de la vision, 1, 65-103). At longer wavelengths, S-cone sensitivity has previously been over-estimated. PMID:10492818

  7. Autosomal dominant nemaline myopathy caused by a novel alpha-tropomyosin 3 mutation.

    PubMed

    Kiphuth, I C; Krause, S; Huttner, H B; Dekomien, G; Struffert, T; Schröder, R

    2010-04-01

    Nemaline myopathy (NM) is a genetically and clinically heterogenous muscle disorder, which is myopathologically characterized by nemaline bodies. Mutations in six genes have been reported to cause NM: Nebulin (NEB Pelin 1999), alpha-skeletal muscle actin (ACTA1 Nowak 1999), alpha-slow tropomyosin (TPM3 Laing 1995), beta-tropomyosin (TPM2 Donner 2002), slow troponin T (TNNT1 Johnston 2000) and cofilin 2 (CFL2 Agrawal 2007). The majority of cases are due to mutation in NEB and ACTA1. We report on the clinical, myopathological and muscle MRI findings in a German family with autosomal dominant NM due to a novel pathogenic TPM3 mutation (p.Ala156Thr). PMID:20012312

  8. Periodic entanglement III: tangled degree-3 finite and layer net intergrowths from rare forests.

    PubMed

    Evans, Myfanwy E; Hyde, Stephen T

    2015-11-01

    Entanglements of two-dimensional honeycomb nets are constructed from free tilings of the hyperbolic plane (H2) on triply periodic minimal surfaces. The 2-periodic nets that comprise the structures are guaranteed by considering regular, rare free tilings in H2. This paper catalogues an array of entanglements that are both beautiful and challenging for current classification techniques, including examples that are realized in metal-organic materials. The compactification of these structures to the genus-3 torus is considered as a preliminary method for generating entanglements of finite θ-graphs, potentially useful for gaining insight into the entanglement of the periodic structure. This work builds on previous structural enumerations given in Periodic entanglement Parts I and II [Evans et al. (2013). Acta Cryst. A69, 241-261; Evans et al. (2013). Acta Cryst. A69, 262-275]. PMID:26522409

  9. Meeting Report: 7th World Congress on Itch

    PubMed Central

    Azimi, Ehsan; Lerner, Ethan A.

    2014-01-01

    The 7th World Congress on Itch was held in Boston in September 2013. This is the biennial meeting of the International Forum for the Study of Itch (IFSI), www.itchforum.net, There were 240 attendees from 17 countries. They spanned clinical practice, academics and patient advocacy while the opportunity for translation was demonstrated as 80 attendees were from industry. A large academic neuroscience contingent was present. There were plenary sessions, basic and clinical tracts, and sixty posters during the 2½ day meeting. The meeting program and 160 abstracts are available at www.itchboston.org and the open access journal, Acta Dermato-Venereologica, www.medicaljournals.se/acta/. This report highlights selected aspects of the congress and the latest advances in the field. PMID:24924756

  10. 4-(3-Fluoro­phen­yl)-1-(propan-2-yl­idene)thio­semicarbazone

    PubMed Central

    Miroslaw, Barbara; Szulczyk, Daniel; Koziol, Anna E.; Struga, Marta

    2011-01-01

    The title compound, C10H12FN3S, crystallizes in the same space group (P21/c) as two polymorphic forms of 4-phenyl-1-(propan-2-yl­idene)thio­semicarbazone [Jian et al. (2005). Acta Cryst. E61, o653–o654; Venkatraman et al. (2005). Acta Cryst. E61, o3914–o3916]. The arrangement of mol­ecules relative to the twofold screw axes is similar to that in the crystal structure of the lower density polymorph. In the solid state, the mol­ecular conformation is stabilized by an intra­molecular N—H⋯N hydrogen bond. The mol­ecules form centrosymmetric R 2 2(8) dimers in the crystal through pairs of N—H⋯S hydrogen bonds. PMID:22220027

  11. Chinese duo fired for scientific fraud

    NASA Astrophysics Data System (ADS)

    Jiao, Li

    2010-02-01

    A major case of academic fraud in China has led to calls for the country to adopt a new system of academic evaluation that steers away from heavily supporting scientists who publish the most papers. The calls have been made after some 70 papers published by Chinese scientists in Acta Crystallographica Section E were retracted from the journal late last year. The authors acknowledged that their analysis had been fabricated.

  12. Measurement of radon gas on major faults in California, USA

    USGS Publications Warehouse

    Zhang, W.; King, C.-Y.

    1994-01-01

    Abundant data have been gathered through measurements of radon gas emission in the soil on several major active faults, such as San Andreas and Calaveras, in California, U.S.A.. They show radon emissions and their spatial variations at the unlocked, locked, and creeping sections of faults with different tectonic movements. The characteristics of these variations and the role of fault gases in the research on earthquake prediction are discussed in this paper. ?? 1994 Acta Seismologica Sinica.

  13. Congenital Heart Defects Are Rarely Caused by Mutations in Cardiac and Smooth Muscle Actin Genes

    PubMed Central

    Khodyuchenko, Tatiana; Zlotina, Anna; Pervunina, Tatiana; Zverev, Dmitry; Malashicheva, Anna; Kostareva, Anna

    2015-01-01

    Background. Congenital heart defects (CHDs) often have genetic background due to missense mutations in cardiomyocyte-specific genes. For example, cardiac actin was shown to be involved in pathogenesis of cardiac septum defects and smooth muscle actin in pathogenesis of aortic aneurysm in combination with patent ductus arteriosus (PDA). In the present study, we further searched for mutations in human α-cardiac actin (ACTC1) and smooth muscle α-actin (ACTA2) genes as a possible cause of atrial septum defect type II (ASDII) and PDA. Findings. Total genomic DNA was extracted from peripheral blood of 86 individuals with ASDs and 100 individuals with PDA. Coding exons and flanking intron regions of ACTC1 (NM_005159.4) and ACTA2 (NM_001613) were amplified by PCR with specific primers designed according to the corresponding gene reference sequences. PCR fragments were directly sequenced and analyzed. Sequence analysis of ACTC1 and ACTA2 did not identify any nucleotide changes that altered the coding sense of the genes. In ACTC1 gene, we were able to detect one previously described nucleotide polymorphism (rs2307493) resulting in a synonymous substitution. The frequency of this SNP was similar in the study and control group, thus excluding it from the possible disease-associated variants. Conclusions. Our results confirmed that the mutations in ACTC1 gene are rare (at least <1%) cause of ASDII. Mutations in ACTA2 gene were not detected in patients with PDA, thus being excluded from the list of frequent PDA-associated genetic defects. PMID:25861618

  14. National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions

    ClinicalTrials.gov

    2015-12-08

    Marfan Syndrome; Turner Syndrome; Ehlers-Danlos Syndrome; Loeys-Dietz Syndrome; FBN1, TGFBR1, TGFBR2, ACTA2 or MYH11 Genetic Mutation; Bicuspid Aortic Valve Without Known Family History; Bicuspid Aortic Valve With Family History; Bicuspid Aortic Valve With Coarctation; Familial Thoracic Aortic Aneurysm and Dissections; Shprintzen-Goldberg Syndrome; Other Aneur/Diss of Thoracic Aorta Not Due to Trauma, <50yo; Other Congenital Heart Disease

  15. What Will They Learn? A Survey of Core Requirements at Our Nation's Colleges and Universities. 2011-12

    ERIC Educational Resources Information Center

    Kempson, Lauri; Bako, Tom; Markley, Eric

    2012-01-01

    What does it mean to be a college graduate? One knows about the time and ever-increasing amount of money that a diploma demands. But when it comes down to what matters--the skills and knowledge acquired--what does a college degree mean? That is the question the American Council of Trustees and Alumni (ACTA) answers in this book. Inside one will…

  16. Characterization of a Cartilage-Like Engineered Biomass Using a Self-Aggregating Suspension Culture Model: Molecular Composition Using FT-IRIS

    PubMed Central

    Kim, Minwook; Kraft, Jeffrey J.; Volk, Andrew C.; Pugarelli, Joan; Pleshko, Nancy; Dodge, George R.

    2011-01-01

    Maintenance of chondrocyte phenotype and robust expression and organization of macromolecular components with suitable cartilaginous properties is an ultimate goal in cartilage tissue engineering. We used a self-aggregating suspension culture (SASC) method to produce an engineered cartilage, “cartilage tissue analog” (CTA). With an objective of understanding the stability of phenotype of the CTA over long periods, we cultured chondrocytes up to 4 years and analyzed the matrix. Both early (eCTAs) (6 months) and aged (aCTAs) (4 years) showed type II collagen throughout with higher concentrations near the edge. Using Fourier transform-infrared imaging spectroscopy (FT-IRIS), proteoglycan/collagen ratio of eCTA was 2.8 times greater than native cartilage at 1 week, but the ratio was balanced to native level (p = 0.017) by 36 weeks. Surprisingly, aCTAs maintained the hyaline characteristics, but there was evidence of calcification within the tissue with a distinct range of intensities. Mineral/matrix ratio of those aCTA with “intensive” calcification was significantly higher (p = 0.017) than the “partial,” but when compared to native bone the ratio of “intensive” aCTAs was 2.4 times lower. In this study we utilized the imaging approach of FT-IRIS and have shown that a biomaterial formed is compositionally closely related to natural cartilage for long periods in culture. We show that this culture platform can maintain a CTA for extended periods of time (4 years) and under those conditions signs of mineralization can be found. This method of cartilage tissue engineering is a promising method to generate cartilaginous biomaterial and may have potential to be utilized in both cartilage and boney repairs. PMID:21630329

  17. Triclinic polymorph of 4-[4-(4-formyl-phen-oxy)but-oxy]benzaldehyde.

    PubMed

    Balić, Tomislav; Marković, Berislav; Balić, Ivana

    2013-01-01

    The title compound, C18H18O4, is a triclinic polymorph of the previously reported monoclinic polymorph [Han & Zhen (2005 ▶). Acta Cryst. E61, o4358-o4359]. In the crystal of the triclinic polymorph, molecules are linked by two pairs of C-H⋯O hydrogen bonds, forming a two-dimensional network parallel to (102), and enclosing loops with graph set motifs of R2(2)(8) and R2(2)(6). PMID:23476387

  18. Triclinic polymorph of 4-[4-(4-formyl­phen­oxy)but­oxy]benzaldehyde

    PubMed Central

    Balić, Tomislav; Marković, Berislav; Balić, Ivana

    2013-01-01

    The title compound, C18H18O4, is a triclinic polymorph of the previously reported monoclinic polymorph [Han & Zhen (2005 ▶). Acta Cryst. E61, o4358–o4359]. In the crystal of the triclinic polymorph, molecules are linked by two pairs of C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (102), and enclosing loops with graph set motifs of R 2 2(8) and R 2 2(6). PMID:23476387

  19. Cosmochemistry and Mineralogy of Primitive Meteorites

    NASA Technical Reports Server (NTRS)

    Buseck, Peter R.

    2003-01-01

    We have produced significant research results during the grant period. These have been reported in five papers published in Geochimica et Cosmochimica Acta and Meteoritics and Planetary Science and several others are in review. We also presented 17 abstracted talks at professional meetings. The citations are given in section 2, and abstracts of the papers are provided in section 3. The full papers are available on request.

  20. Parameter-free exchange potential for excitation in the density-functional theory: Application to excitation energies within the fractional-occupation approach

    NASA Astrophysics Data System (ADS)

    Nagy, Á.

    1990-10-01

    The density-functional theory for ensembles of fractional occupation formulated by Gross, Oliveira, and Kohn [Phys. Rev. A 37, 2821 (1988)] has been applied. The excitation energies of several atoms have been determined using a parameter-free exchange potential of Gáspár [Acta Phys. Hung. 35, 213 (1974)]. The calculated excitation energies are in good agreement with the experimental values.

  1. Thin film adhesion by nanoindentation-induced superlayers. Final report

    SciTech Connect

    Gerberich, William W.; Volinsky, A.A.

    2001-06-01

    This work has analyzed the key variables of indentation tip radius, contact radius, delamination radius, residual stress and superlayer/film/interlayer properties on nanoindentation measurements of adhesion. The goal to connect practical works of adhesion for very thin films to true works of adhesion has been achieved. A review of this work titled ''Interfacial toughness measurements of thin metal films,'' which has been submitted to Acta Materialia, is included.

  2. Finite gradient elasticity and plasticity: a constitutive mechanical framework

    NASA Astrophysics Data System (ADS)

    Bertram, Albrecht

    2015-11-01

    Following a suggestion by Forest and Sievert (Acta Mech 160:71-111, 2003), a constitutive frame for a general gradient elastoplasticity for finite deformations is established. The basic assumptions are the principle of Euclidean invariance and the isomorphy of the elastic ranges. Both the elastic and the plastic laws include the first and the second deformation gradient. The starting point is an objective expression for the stress power.

  3. A survey of recently published papers on orthopedics in the Brazilian scientific press

    PubMed Central

    Rocha-e-Silva, Mauricio; Gomes, Ariane Maris

    2012-01-01

    This paper is a review of articles published in Brazilian scientific periodicals in recent years. Its main purpose is to bring to the attention of the readership of Acta Ortopedica Brasileira original contributions to the field published in non-specialized journals. We hope that this will serve as a general scientific update for readers. The review includes works published in six ISI indexed non-orthopedic journals, following a literature search conducted in fourteen such journals. PMID:24453633

  4. MicroRNA-208b Alleviates Post-Infarction Myocardial Fibrosis in a Rat Model by Inhibiting GATA4

    PubMed Central

    Zhou, Chaoyuan; Cui, Qintao; Su, Guobao; Guo, Xiaoliang; Liu, Xiaochen; Zhang, Jie

    2016-01-01

    Background Myocardial infarction affects the health of many people. Post-infarction myocardial fibrosis has attracted much attention, but details of the mechanism remain elusive. In this study, the role of microRNA-208b (miR-208b) in modulating post-infarction myocardial fibrosis and the related mechanism were investigated. Material/Methods A rat model of myocardial infarction induced by ligating the left anterior descending artery was used to analyze the expression and roles of miR-208b by overexpression with the lentivirus vector of pre-miR-208b. Myocardial function was assessed and the expression of fibrosis-related factors type I collagen (COL1) and ACTA2 (alias αSMA) was detected. Myocardial fibroblasts isolated from newborn rats were transfected with luciferase reporter vectors containing wild-type or mutant Gata4 3′ UTR to verify the relationship between Gata4 and miR-208b. We then transfected the specific small interference RNA of Gata4 to detect changes in COL1 and ACTA2. Results miR-208b was down-regulated in hearts of model rats (P<0.01). Overexpressing miR-208b improved myocardial functions, such as reducing the infarction area (P<0.05) and promoting LVEF and LVFS (P<0.01), and inhibited COL1 and ACTA2 (P<0.01). Luciferase reporter assay proved Gata4 to be the direct target of miR-208b, with the target sequence in the 3′UTR. Inhibiting GATA4 resulted in the down-regulation of COL1 and ACTA2, suggesting that the role of miR-208b was achieved via regulating GATA4. Conclusions This study demonstrates the protective function of miR-208b via GATA4 in post-infarction myocardial fibrosis, providing a potential therapeutic target for treating myocardial fibrosis. PMID:27236543

  5. Growth of Mouse Oocytes to Maturity from Premeiotic Germ Cells In Vitro

    PubMed Central

    Zhang, Zhi-Peng; Liang, Gui-Jin; Zhang, Xi-Feng; Zhang, Guo-Liang; Chao, Hu-He; Li, Lan; Sun, Xiao-Feng; Min, Ling-Jiang; Pan, Qing-Jie; Shi, Qing-Hua; Sun, Qing-Yuan; De Felici, Massimo; Shen, Wei

    2012-01-01

    In the present study, we established an in vitro culture system suitable for generating fertilizable oocytes from premeiotic mouse female germ cells. These results were achieved after first establishing an in vitro culture system allowing immature oocytes from 12–14 day- old mice to reach meiotic maturation through culture onto preantral granulosa cell (PAGC) monolayers in the presence of Activin A (ActA). To generate mature oocytes from premeiotic germ cells, pieces of ovaries from 12.5 days post coitum (dpc) embryos were cultured in medium supplemented with ActA for 28 days and the oocytes formed within the explants were isolated and cocultured onto PAGC monolayers in the presence of ActA for 6–7 days. The oocytes were then subjected to a final meiotic maturation assay to evaluate their capability to undergo germinal vesicle break down (GVBD) and reach the metaphase II (MII) stage. We found that during the first 28 days of culture, a significant number of oocytes within the ovarian explants reached nearly full growth and formed preantral follicle-like structures with the surrounding somatic cells. GSH level and Cx37 expression in the oocytes within the explants were indicative of proper developmental conditions. Moreover, the imprinting of Igf2r and Peg3 genes in these oocytes was correctly established. Further culture onto PAGCs in the presence of ActA allowed about 16% of the oocytes to undergo GVBD, among which 17% reached the MII stage during the final 16–18 hr maturation culture. These MII oocytes showed normal spindle and chromosome assembly and a correct ERK1/2 activity. About 35% of the in vitro matured oocytes were fertilized and 53.44% of them were able to reach the 2-cell stage. Finally, around 7% of the 2-cell embryos developed to the morula/blastocyst stage. PMID:22848595

  6. Practical Astronomical Activities during Daytime. (Spanish Title: Actividades Astronómicas Prácticas Diurnas.) Atividades Astronômicas Práticas Diurnas

    NASA Astrophysics Data System (ADS)

    Jackson, Eric

    2009-12-01

    relacionadas al mal tiempo. El problema de no tener suficientes actividades prácticas, la sensación de poseer conocimientos inadecuados, la necesidad de disponer de equipamiento astronómico y experiencia suelen ser demasiado intimidantes para que los profesores introduzcan la materia en sus clases. Si la Astronomía iba a ser introducida, entonces era preciso encontrar una forma de resolver estas dificultades. Nuestro grupo, trabajando con maestros y alumnos dentro de un marco constructivista, encontró que los principios de la Astronomía pueden ser descubiertos durante el día, en cuanto los alumnos están en la escuela. Trabajando de forma cooperativa los alumnos midieron y registraron observaciones de sus propias sombras causadas por los movimientos de la estrella más próxima, el Sol, y nuestro planeta Tierra. Debido a que los alumnos se involucraran tan personalmente en las actividades, estuvieron mucho más interesados en los resultados del estudio. La Astronomía pasó a ser un desafío para el maestro y sus alumnos cuando aplicaron sus experiencias diurnas a la observación nocturna desde sus casas, reportada después en clase. Estas atividades astronômicas diurnas surgiram de uma investigação feita na Nova Zelândia por um grupo de professores e astrônomos a respeito dos problemas do ensino da Astronomia. Este trabalho mostrou que a Astronomia é geralmente considerada uma disciplina difícil de ensinar, tradicionalmente baseada em livros, filmes e modelos. Os mais afortunados podem ter feito alguma visita a um observatório ou planetário, e os mais avançados podem talvez ter tentado uma sessão de observação noturna, as quais sofrem às vezes de dificuldades relacionadas ao tempo. O problema de não dispor de suficientes atividades práticas, a sensação de possuir conhecimentos inadequados, a necessidade de dispor de equipamento astronômico e experiência tem sido, em geral, demasiado intimidante para que os professores introduzam a matéria nas suas

  7. Clinical, pathological, and genetic analysis of a Korean family with thoracic aortic aneurysms and dissections carrying a novel Asp26Tyr mutation.

    PubMed

    Yoo, Eun-Hyung; Choi, Seung Hyuk; Jang, Shin Yi; Suh, Yeon-Lim; Lee, Inchul; Song, Jae-Kwan; Choe, Yeon Hyeon; Kim, Jong-Won; Ki, Chang-Seok; Kim, Duk-Kyung

    2010-01-01

    Non-syndromic familial thoracic aortic aneurysms and dissections (TAADs), inherited in an autosomal dominant manner in up to 19% of patients, are genetically heterogeneous. The ACTA2 gene, which encodes the vascular smooth muscle cell (SMC)-specific isoform of alpha-actin, is known to cause TAADs and occlusive vascular diseases, including coronary artery disease and premature ischemic stroke. We have investigated a Korean family with DeBakey type I aortic dissection related to pregnancy and a strong family history of TAADs. All affected family members underwent surgical repair of the ascending aorta. Other clinical features of familial TAAD, including inguinal hernias, iris flocculi, and livedo reticularis, were not observed. Histologic studies of aortic tissues showed medial degeneration and SMC hyperplasia in the aorta, consistent with previous observations. Molecular analyses of the ACTA2 gene showed a novel heterozygous missense mutation (c.76G>T; p.Asp26Tyr). Further analysis of a female patient and members of her family revealed that two affected sisters and her asymptomatic son had the same mutation. The novel Asp26Tyr mutation resides in SM alpha-actin subdomain 1 and is linked to TAAD with hypertrophy and disarray of SMCs and severe migraine, but not to livedo reticularis or iris flocculi. This study expands the spectrum of mutations of the ACTA2 gene by identifying a novel missense mutation. This is the first report of a pathologically- and genetically-confirmed family with TAAD in Korea. PMID:20689142

  8. Mutations of the Act Promoter in Myxococcus xanthus▿ †

    PubMed Central

    Gronewold, Thomas M. A.; Kaiser, Dale

    2007-01-01

    Mutations within the −12 and −24 elements provide evidence that the act promoter is recognized by sigma-54 RNA polymerase. Deletion of the −20 base pair, which lies between the two conserved elements of sigma-54 promoters, decreased expression by 90%. In addition, mutation of a potential enhancer sequence, around −120, led to an 80% reduction in act gene expression. actB, the second gene in the act operon, encodes a sigma-54 activator protein that is proposed to be an enhancer-binding protein for the act operon. All act genes, actA to actE, are expressed together and constitute an operon, because an in-frame deletion of actB decreased expression of actA and actE to the same extent. After an initially slow phase of act operon expression, which depends on FruA, there is a rapid phase. The rapid phase is shown to be due to the activation of the operon expression by ActB, which completes a positive feedback loop. That loop appears to be nested within a larger positive loop in which ActB is activated by the C signal via ActA, and the act operon activates transcription of the csgA gene. We propose that, as cells engage in more C signaling, positive feedback raises the number of C-signal molecules per cell and drives the process of fruiting body development forward. PMID:17189369

  9. Chromite alteration processes within Vourinos ophiolite

    NASA Astrophysics Data System (ADS)

    Grieco, Giovanni; Merlini, Anna

    2012-09-01

    The renewed interest in chromite ore deposits is directly related to the increase in Cr price ruled by international market trends. Chromite, an accessory mineral in peridotites, is considered to be a petrogenetic indicator because its composition reflects the degree of partial melting that the mantle experienced while producing the chromium spinel-bearing rock (Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993). However, the understanding of chromite alteration and metamorphic modification is still controversial (e.g. Evans and Frost in Geochim Cosmochim Acta 39:959-972, 1975; Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993; Oze et al. in Am J Sci 304:67-101, 2004). Metamorphic alteration leads to major changes in chromite chemistry and to the growth of secondary phases such as ferritchromite and chlorite. In this study, we investigate the Vourinos complex chromitites (from the mines of Rizo, Aetoraches, Xerolivado and Potamia) with respect to textural and chemical analyses in order to highlight the most important trend of alteration related to chromite transformation. The present study has been partially funded by the Aliakmon project in collaboration between the Public Power Corporation of Greece and Institute of Geology and Mineral Exploration of Kozani.

  10. Retraction statement: Dynamics of Cytochrome C Oxidase Activity in Acute Ischemic Stroke' by Selaković, V.M., Jovanović, M.D., Mihajlović, R.R. and Radenović, L.L.J.

    PubMed

    2016-10-01

    The above article from Acta Neurologica Scandinavica, published online on 7 April 2005 in Wiley Online Library (wileyonlinelibrary.com) and in Volume 111, pp. 329-332, has been retracted by agreement between the journal Editor in Chief, Professor Elinor Ben-Menachem, and John Wiley & Sons Ltd. The article has been retracted because a similar article had previously been published in the Jugoslovenska medicinska biohemija in 2003. The authors presumed that since the journal was no longer existing, they felt the need to re-publish their work in Acta Neuorologica Scandinavica. However, in the consideration of the Journal, this constitutes dual publication. References SelakovićVM, JovanovićMD, MihajlovićR, RadenovićLLJ. Cytochrome c oxidase in patients with acute ischaemic brain disease. Jugoslovenska medicinska biohemija. 2003;22:329-334. SelakovićVM, JovanovićMD, MihajlovićRR, RadenovićLLJ. Dynamics of cytochrome c oxidase activity in acute ischemic stroke. Acta Neurol Scand. 2005;111:329-332. PMID:27592845

  11. Determination of Structural and Vibrational Properties of 5-QUINOLINECARBOXALDEHYDE Using Experimental Ft-Ir Ft-Raman Techniques and Theoretical HF and DFT Methods

    NASA Astrophysics Data System (ADS)

    Kumru, Mustafa; Kocademir, Mustafa; Bardakci, Tayyibe

    2013-06-01

    Quinoline derivatives have been used in several pharmaceuticals. They have vital roles in regulating the functions of DNA and cancerous cells. It's necessary to determine the structures and spectroscopic properties of quinoline derivates. In this study, the FT-IR (including mid and far regions) and FT-Raman spectra of 5-quinolinecarboxaldehyde have been investigated. Hartree-Fock (HF) and density functional B3LYP calculations have also been employed with the 6-311++G(d,p) basis set for investigating the structural and spectroscopic properties of the cis and trans conformers of 5-quinolinecarboxaldehyde. Experimental and theoretical results have been compared and the results are in good agreement with each other. Keywords: 5-quinolinecarboxaldehyde; Vibrational Spectroscopy; FT-IR spectra; FT-Raman spectra; Vibrational Modes; HF; DFT [1] V. Kucuk, A. Altun, M. Kumru, Spectrochim. Acta Part A 85(2012)92-98 [2] M. Kumru, V. Kucuk, T. Bardakci, Spectrochim. Acta Part A 90(2012)28-34 [3] M. Kumru, V. Kucuk, M. Kocademir, Spectrochim. Acta Part A, 96 (2012) 242-251 We thank the Turkish Scientific and Technical Research Council (TUBITAK) for their financial support through National Postdoctoral Research Scholarship Programme and Scientific Research Fund of Fatih University under the project number P50011001 G (1457).

  12. STSHV a teleinformatic system for historic seismology in Venezuela

    NASA Astrophysics Data System (ADS)

    Choy, J. E.; Palme, C.; Altez, R.; Aranguren, R.; Guada, C.; Silva, J.

    2013-05-01

    From 1997 on, when the first "Jornadas Venezolanas de Sismicidad Historica" took place, a big interest awoke in Venezuela to organize the available information related to historic earthquakes. At that moment only existed one published historic earthquake catalogue, that from Centeno Grau published the first time in 1949. That catalogue had no references about the sources of information. Other catalogues existed but they were internal reports for the petroleum companies and therefore difficult to access. In 2000 Grases et al reedited the Centeno-Grau catalogue, it ended up in a new, very complete catalogue with all the sources well referenced and updated. The next step to organize historic seismicity data was, from 2004 to 2008, the creation of the STSHV (Sistema de teleinformacion de Sismologia Historica Venezolana, http://sismicidad.hacer.ula.ve ). The idea was to bring together all information about destructive historic earthquakes in Venezuela in one place in the internet so it could be accessed easily by a widespread public. There are two ways to access the system. The first one, selecting an earthquake or a list of earthquakes, and the second one, selecting an information source or a list of sources. For each earthquake there is a summary of general information and additional materials: a list with the source parameters published by different authors, a list with intensities assessed by different authors, a list of information sources, a short text summarizing the historic situation at the time of the earthquake and a list of pictures if available. There are searching facilities for the seismic events and dynamic maps can be created. The information sources are classified in: books, handwritten documents, transcription of handwritten documents, documents published in books, journals and congress memories, newspapers, seismologic catalogues and electronic sources. There are facilities to find specific documents or lists of documents with common characteristics

  13. Bidirectional reflectance spectroscopy of carbonaceous chondrites: Implications for water quantification and primary composition

    NASA Astrophysics Data System (ADS)

    Garenne, A.; Beck, P.; Montes-Hernandez, G.; Brissaud, O.; Schmitt, B.; Quirico, E.; Bonal, L.; Beck, C.; Howard, K. T.

    2016-01-01

    In this study, we measured bidirectional reflectance spectra (0.5-4.0 μm) of 24 CMs, five CRs, one CI, one CV, and one C2 carbonaceous chondrites. These meteorites are known to have experienced an important variability in their relative degrees of aqueous alteration degree (Rubin et al. [2007]. Geochim. Cosmochim. Acta 71, 2361-2382; Howard et al. [2009]. Geochim. Cosmochim. Acta 73, 4576-4589; Howard et al. [2011]. Geochim. Cosmochim. Acta 75, 2735-2751; Alexander et al. [2013]. Geochim. Cosmochim. Acta 123, 244-260). These measurements were performed on meteorite powders inside an environmental cell under a primary vacuum and heated at 60 °C in order to minimize adsorbed terrestrial water. This protocol allows controlling of atmospheric conditions (i.e. humidity) in order to avoid contamination by terrestrial water. We discuss various spectral metrics (e.g. reflectance, band depth, single-scattering albedo, …) in the light of recent bulk composition characterization (Howard et al. [2009]. Geochim. Cosmochim. Acta 73, 4576-4589; Howard et al. [2015]. Geochim. Cosmochim. Acta 149, 206-222; Alexander et al. [2012]. Science 337, 721; Beck et al. [2014]. Icarus 229, 263-277; Garenne et al. [2014]. Geochim. Cosmochim. Acta 137, 93-112). This study reveals variability of reflectance among meteorite groups. The reflectance is not correlated with carbon or hydrogen abundance neither with measured grain size distribution. We suggest that it is rather controlled by the nature of accreted components, in particular the initial matrix/chondrule proportion. Band depth, integrated band depth, mean optical path length, normalized optical path length, effective single-particle absorption thickness were calculated on the so called 3-μm band for reflectance spectra and for single scattering albedo spectra. They were compared with hydrated phase proportions from previous study on the same meteorites by thermogravimetric analyses and infrared spectroscopy in transmission. We find

  14. Física e Arte nas Estações do Ano

    NASA Astrophysics Data System (ADS)

    Pessôa Queiroz, Glória; da Conceição Barbosa Lima, Maria; Navarro Vasconcellos das Mercês, Maria

    2004-12-01

    The paper deals with the subject of the Four Seasons, exploring elements of Science and the Art in order to motivate students or public of museums of science and technology to understand it from their current cultural experiences and of old times. Physics joins to Astronomy to explain the phenomenon, while the use of Music and Painting make possible the immersion in the subject in way to many trips to the imagination capable to awake emotions.A proposal didactic is presented and justified for some consensus of the research in the area of teaching-learning of science, since that related to the persistent alternative conceptions concerning the causes of the changes observed at the different times of the year until the qualitative modelling of phenomena that appeals three-dimensional pedagogical models. Such proposal was developed in the activity named " Hiper interesting Talk: The Four Seasons, Science and Art" in the first Sunday of August/2003 in the Museum of Astronomy, MAST. O artigo trata do tema das Estações do Ano, explorando elementos da Ciência e da Arte como forma de motivar estudantes ou público de museus de ciência e tecnologia a compreendê-lo a partir de vivências culturais atuais e de outras épocas. A Física se junta à Astronomia para explicar o fenômeno, enquanto a Música e a Pintura possibilitam a imersão no tema em meio a muitas viagens à imaginação capazes de despertar emoções.Uma proposta didática é apresentada e justificada por consensos das muitas pesquisas na área de ensino-aprendizagem de ciências, desde os que se referem às persistentes concepções alternativas acerca das causas das mudanças observadas nas diferentes épocas do ano até à modelagem qualitativa de fenômenos que recorre a modelos pedagógicos tridimensionais. Tal proposta foi desenvolvida na atividade "Bate papo Hiperinteressante: As Quatro Estações, Ciência e Arte" realizada no primeiro domingo do mês de agosto de 2003 no Museu de Astronomia.

  15. Camões e a cosmogonia

    NASA Astrophysics Data System (ADS)

    Costa, J. M.

    2003-08-01

    Os Lusíadas, escrito por Luis de Camões em 1572, é um poema épico renascentista e a visão Cosmogônica do autor é apresentada, principalmente, no último canto do poema, quando Tétis mostra ao Gama a Máquina do Mundo. A Cosmogonia de Camões neste poema reflete uma visão de uma época de transição, que ainda não incorporou os elementos da revolução Copernicana. É uma visão Grego- Ptolomaica e também medieval. O poeta guia-se pela tradução e notas feita por Pedro Nunes, inventor do Nonio, do Tratado da Esfera "De Sphaera" do Astrônomo Inglês John Holywood, mais conhecido pelo nome latinizado de Johannes Sacrobosco. Outra provável fonte de Camões, de acordo com Luciano Antonio Pereira da Silva em Astronomia de os Lusíadas, é o "Theoricae novae Planetarum" (1460) do astrólogo Alemão Jorge Purbáquio (1423 - 1461). A Astronomia de Os Lusíadas representa a ciência do tempo de Camões. Camões nunca emprega a palavra constelação e seu catálogo é bastante completo. A Máquina do Mundo tem a Terra no centro. Em redor, em círculos concêntricos, a lua (Diana), Mercúrio, Vênus, o Sol (Febo), Marte, Júpiter e Saturno. Envolvendo estes astros tem o firmamento seguido pelo "Céu Áqueo" ou cristalino, depois o 1o Móbil, esfera que arrasta todas as outras consigo. Este trabalho, multidisciplinar, serve tanto para ensinar aos alunos da Física como das Ciências Humanas, a concepção de mundo do renascimento de uma forma belamente poética em versos decassílabos Este trabalho também ajuda na apreciação do maior clássico da língua portuguesa e mostra como as Ciências e as artes, em geral, estão correlacionadas e refletem a visão de mundo da época em que foi produzida.

  16. Determinação da massa de júpiter a partir das órbitas de seus satélites: um experimento didático

    NASA Astrophysics Data System (ADS)

    Schlickmann, M. S.; Saito, R. K.; Becker, D. A.; Rezende, M. F., Jr.; Cid Fernandes, R.

    2003-08-01

    Este trabalho apresenta o roteiro piloto de uma prática observacional em astronomia, junto com os primeiros resultados obtidos nesta fase de implementacão. O projeto, que será executado em duas etapas, visa introduzir noções de Astronomia a alunos do Ensino Médio e iniciantes nos cursos de Física. O experimento consiste em medir as órbitas dos satélites Galileanos e, a partir da análise dos dados coletados, verificar a validade da Lei das órbitas de Kepler, determinando a massa do planeta Júpiter. Em uma primeira etapa, as observações serão feitas utilizando um telescópio Meade LX200 10" e câmera CCD para obter uma seqüência de imagens do planeta, que possibilitará medir o movimento de seus satélites. A segunda etapa terá início a partir do funcionamento do telescópio em modo robótico, com a possibilidade de observações via internet por instituições de ensino. Para o desenvolvimento deste experimento foram inicialmente coletadas várias imagens de Júpiter obtidas com os instrumentos citados acima. Estas imagens serviram como base para confecção dos roteiros para a experiência no nível médio e superior. Os roteiros serão inicialmente apresentados em uma home-page. Nela também se buscará uma contextualização histórica da experiência bem como o estabelecimento de relações com professores e alunos, propostas metodológicas e a disponibilização dos programas computacionais necessários para a utilização "on-line" pelos usuários. O projeto conta com apoio da Fundação VITAE.

  17. A Three-Planet Extrasolar System

    NASA Astrophysics Data System (ADS)

    Lovis, Christophe; Mayor, Michel; Pepe, Francesco; Queloz, Didier; Udry, Stéphane; Santos, Nuno C.; Alibert, Yann; Benz, Willy; Mordasini, Christoph; Bouchy, François; Correia, Alexandre C. M.; Laskar, Jacques; Bertaux, Jean-Loup; Sivan, Jean-Pierre

    2006-06-01

    Using the ultra-precise HARPS spectro-graph on ESO’s 3.6-m telescope at La Silla, a team of astronomers1 has discovered that a nearby star is host to three Neptune-mass planets. The in-nermost planet is most probably rocky, while the outermost is the first known Neptune-mass planet to reside in the habitable zone. This unique system is likely further enriched by an asteroid belt. Z% Lovis et al. 2006, Nature 441, 305. The team is composed of Christophe Lovis, Michel Mayor, Francesco Pepe, Didier Queloz, and Stéphane Udry (Observatoire de l’Université de Genève, Switzerland), Nuno C. Santos (Observatoire de l’Uni-versité de Genève, Switzerland, Centro de Astro-nomia e Astrofisica da Universidade de Lisboa and Centro de Geofisica de Evora, Portugal), Yann Alibert, Willy Benz, Christoph Mordasini (Physikalisches Institut der Universität Bern, Switzerland), François Bouchy (Observatoire de Haute-Provence and IAP, France), Alexandre C. M. Correia (Uni-versidade de Aveiro, Portugal), Jacques Laskar (IMCCE-CNRS, Paris, France), Jean-Loup Bertaux (Service d’Aéronomie du CNRS, France), and Jean-Pierre Sivan (Laboratoire d’Astrophysique de Marseille, France).

  18. Active remote observing system for the 1-m telescope at Tonantzintla Observatory

    NASA Astrophysics Data System (ADS)

    Bernal, Abel; Martínez, Luis A.; Hernández, Héctor; Garfias, Fernando; Ángeles, Fernando

    2006-06-01

    We have designed and installed a new active remote observing system for the 1-m, f/15 telescope at the Tonantzintla Observatory. This remote system is operated in real-time through the Internet, allowing an observer to control the building, the telescope (pointing, guiding and focusing) and the CCD image acquisition at the main and finder telescopes from the Instituto de Astronomia headquarters in Mexico City (150 KM away). The whole system was modeled within the Unified Modeling Language (UML) and the design has proved to be versatile enough for a variety of astronomical instruments. We describe the system architecture and how different subsystems (telescope control, main telescope and finder image acquisition, weather station, videoconference, etc.) that are based on different operative system platforms (Linux, Windows, uIP) have been integrated. We present the first results of an IPv6 over IPv4 tunnel. Recent remote direct imaging and spectroscopic observations have been used to test the astronomical site. We conclude that this remote system is an excellent tool for supporting research and graduated observational astronomy programs.

  19. BeppoSAX Observations of MKN 110

    NASA Technical Reports Server (NTRS)

    Nicastro, Fabrizio; Oliversen, Ronald J. (Technical Monitor)

    2002-01-01

    Mkn 110 is a bright, nearby Seyfert 1 galaxy, which underwent a long optical monitoring campaign, during the past 12 years. Optical observations show that Mkn 110 vary, both in flux and spectral shape. The intensity and width of its Broad Emission Lines (BELs) also vary, from typical Seyfert 1, to typical Narrow Line Seyfert 1 (NLSyl) values, so suggesting that this could be the first supermassive black holes where accretion state related transitions, as frequently observed in stellar-size black holes, have finally been observed. To verify these suggestions we asked to monitor Mkn 110 with BeppoSAX with three 50 ksec observations six months apart. The goal of the proposal was to observe spectral variations in X-ray, already suggested by previous, existing ROSAT (Roentgen Satellite) and ASCA (Advanced Satellite for Cosmology and Astrophysics) observations of the same source. The first of these three SAX (Satellite per Astronomia X) observations was taken on May 2000, and lacks the Low-Energy instrument (0.1-2 keV is the band in which NLSy1 and Sy1 X-ray spectra differ most).

  20. Variations of a Constant -- On the History of Precession

    NASA Astrophysics Data System (ADS)

    Kokott, W.

    The precession of the equinoxes, the phenomenon which defines one of the fundamental constants of astronomy, has been with us for more than two millennia. Discovered by Hipparchos who did notice a systematic difference of his star positions as compared with older observations, subsequently adopted by Ptolemaios, its correct value became the object of prolonged controversy. The apparent variability of the precession led to the superimposition of a so-called ''trepidation``, an oscillation of typically +/- 9 deg amplitude and 7000 years period, over a linear precession of only 26 arcsec per annum. This construction, finalized in the Alfonsine Tables (ca. 1280), did work for less than two centuries. The motion of the vernal equinox, at 39 arcsec p.a. too small from the outset, decreases according to this theory to 34 arcsec in the year 1475, the first year covered by the printed version of Johannes Regiomontanus' Ephemerides. Regiomontanus had to re-adjust his longitudes to the real situation, but the difficulties caused by the apparent nonlinearity did persist, leading to a prolonged debate which was finally put to rest by Tycho Brahe. Subsequent to Edmond Halley's successful derivation of a modern value of the precessional constant, again by comparing contemporary star positions with the Almagest catalogue, and Bradley's discovery of the nutation, the last long-term comparison of modern with Ptolemaic coordinates was published by Bode (1795). Shortly after, the analytical theory of precession was established by Bessel in his Fundamenta Astronomiae (1818).

  1. Introducing CUBES: the Cassegrain U-band Brazil-ESO spectrograph

    NASA Astrophysics Data System (ADS)

    Bristow, Paul; Barbuy, Beatriz; Macanhan, Vanessa B.; Castilho, Bruno; Dekker, Hans; Delabre, Bernard; Diaz, Marcos; Gneiding, Clemens; Kerber, Florian; Kuntschner, Harald; La Mura, Giovanni; Reiss, Roland; Vernet, J.

    2014-07-01

    CUBES is a high-efficiency, medium-resolution (R ≃ 20, 000) spectrograph dedicated to the "ground based UV" (approximately the wavelength range from 300 to 400nm) destined for the Cassegrain focus of one of ESO's VLT unit telescopes in 2018/19. The CUBES project is a joint venture between ESO and Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG) at the Universidade de São Paulo and the Brazilian Laboratório Nacional de Astrofísica (LNA). CUBES will provide access to a wealth of new and relevant information for stellar as well as extra-galactic sources. Principle science cases include the study of heavy elements in metal-poor stars, the direct determination of carbon, nitrogen and oxygen abundances by study of molecular bands in the UV range and the determination of the Beryllium abundance as well as the study of active galactic nuclei and the inter-galactic medium. With a streamlined modern instrument design, high efficiency dispersing elements and UV-sensitive detectors, it will enable a significant gain in sensitivity over existing ground based medium-high resolution spectrographs enabling vastly increased sample sizes accessible to the astronomical community. We present here a brief overview of the project, introducing the science cases that drive the design and discussing the design options and technological challenges.

  2. Where is the Phosphorus in Cometary Volatiles?

    NASA Astrophysics Data System (ADS)

    Boice, Daniel C.; de Almeida, Amaury

    2015-08-01

    Phosphorus is a key element in all living organisms but its role in life's origin is not well understood. Phosphorus-bearing compounds have been observed in space, are ubiquitous in meteorites in small quantities, and have been detected as part of the dust component in comets Halley and Wild 2. However, searches for P-bearing species in the gas phase in cometary comae have been unsuccessful. We present results of the first quantitative study of P-bearing molecules in comets to identify likely species containing phosphorus. We found reaction pathways of gas-phase and photolytic chemistry for simple P-bearing molecules likely to be found in comets and important for prebiotic chemistry. We hope to aid future searches for this important element, especially the Rosetta Mission to Comet 67P/Churyumov-Gerasimenko, possibly shedding light on issues of comet formation (time and place) and understanding prebiotic to biotic evolution of life.Acknowledgements: We greatly appreciate support from the NSF Planetary Astronomy Program under Grant No. 0908529 and the Instituto de Astronomia, Geofísica e Ciências Atmosféricas at the University of São Paulo.

  3. Kepler, Galilei, the telescope and the consequences. (German Title: Kepler, Galilei, das Fernrohr und die Folgen)

    NASA Astrophysics Data System (ADS)

    Gaulke, Karsten; Hamel, Jürgen

    The papers of this volume are dedicated to Johannes Kepler, the astronomy of his time, and the consequences of his researches. They deal with the reception on the Copernican system of the world at the court of landgrave William IV in Kassel and the use of astronomy at a princely court in the 16th century, exemplified by the Kassel residence. Two contributions discuss a text fragment in Kepler's Astronomia Nova and the dimensions of the geo- and heliocentric systems of the world in Kepler's Mysterium Cosmographicum. Other contributions deal with mathematical aspects un Kepler's exchange of letters, the biography of Kepler's discussion partner Ph. Feselius, as well as the early reception of the Tabulae Rudolphinae in the calendar literature, telescopes in Kepler's time, Chr. Scheiner's optical theory of the eye, and finally in the continuation of the heliocentric world system by Otto von Guericke's natural philosophy and science. In conclusion, the documents of the planned call of Kepler to Rostock university, as well as the first publication of a recently found, hitherto unknown letter by Kepler.

  4. Editorial

    NASA Astrophysics Data System (ADS)

    Bruzzi, Mara; Pace, Emanuele; Talamonti, Cinzia

    2013-12-01

    The 9th edition of the International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices (RESMDD), held in Florence, at Dipartimento di Fisica ed Astronomia on October 9-12, 2012, was aimed at discussing frontier research activities in several application fields as in nuclear and particle physics, astrophysics, medical and solid-state physics. Main topics discussed in this conference are tracking performance of heavily irradiated silicon detectors, developments required for the luminosity upgrade of the Large Hadron Collider (HL-LHC), radiation effects on semiconductor materials for medical (radiotherapy dosimeters, imaging devices), astrophysics (UV, X- and γ-ray detectors) and environmental applications, microscopic defect analysis of irradiated semiconductor materials and related radiation hardening technologies. On the first day the conference hosted a short course intended to introduce fundamentals in the development of semiconductor detectors for medical applications to graduate and PhD students, post-docs and young researchers, both engineers and physicists. Directors of the School were Prof. Marta Bucciolini of the University of Florence and INFN, Italy and Dr. Carlo Civinini, INFN Firenze, Italy. Emphasis was placed on the underlying physical principles, instrument design, factors affecting performance, and applications in both the clinical and preclinical applications. The School was attended by nearly 40 students/ young researchers. We warmly thank the Directors for organizing this interesting event and the professors and researchers who gave lessons, for sharing their experience and knowledge with the students.

  5. Library of high and mid-resolution spectra in the CA II H & K, Hα, Hβ NA i D1, D2, and He i D3 line regions of F, G, K and M field stars

    NASA Astrophysics Data System (ADS)

    Montes, D.; Martin, E. L.; Fernandez-Figueroa, M. J.; Cornide, M.; de Castro, E.

    1997-06-01

    In this work we present spectroscopic observations centered in the spectral lines most widely used as optical indicators of chromospheric activity (Hα, Hβ, Ca ii H & K, and He i D3) in a sample of F, G, K and M chromospherically inactive stars. The spectra have been obtained with the aim of providing a library of high and mid-resolution spectra to be used in the application of the spectral subtraction technique to obtain the active-chromosphere contribution to these lines in chromospherically active single and binary stars. This library can also be used for spectral classification purposes. A digital version with all the spectra is available via ftp and the World Wide Web (WWW) in both ASCII and FITS formats. Based on observations made with the Isaac Newton telescope and the William Herschel Telescope operated on the island of La Palma by the Royal Greenwich Observatory at the Spanish Observatorio del Roque de Los Muchachos of the Instituto de Astrofisica de Canarias, and with the 2.2 m telescope of the Centro Astronomico Hispano-Aleman of Calar Alto (Almeria, Spain) operated jointly by the Max Planck Institut fur Astronomie (Heidelberg) and the Spanish Comision Nacional de Astronomia. The spectra of the stars listed in Table \\protect\\ref{tab:par} are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

  6. The first printed edition of Tycho's 1004 star catalogue

    NASA Astrophysics Data System (ADS)

    Truffa, Giancarlo

    One of the most important contribution to astronomy by Tycho Brahe has been the preparation of a star catalogue based on new observations. It is known in two versions, the shorter with 777 stars, was published in the first volume of Astronomiae Instauratae Progymnasmata, published in 1602 after Tycho's death. The longest version, containing 1004 stars, was distributed in manuscript form by Tycho himself only to important people, scientists and rulers, of his time as testified by the extant copies. This version is commonly considered to be printed for the first time by Kepler as an appendix to the Rudolphine Tables. Indeed it was printed in 1604 by a little known Italian mathematician, Francesco Pifferi, who, using the manuscripts sent to Magini and to the Venice Republic, inserted the new star catalogue in his Italian translation of Clavius' In Sphaeram Ioannis de Sacro Bosco commentarius. This work had very little distribution and the few references to it in contemporary works did not mentioned the new additions so it was completely forgotten.

  7. Structure of the spectrograph ESOPO

    NASA Astrophysics Data System (ADS)

    Sierra, G.; Farah, A.; Gonzalez, J.; Pedrayes, M.; Arroyo, M.; Avila, G.; Cobos, F.; Colorado, E.; Córdova, A.; Costero, R.; Chapa, O.; Echevarria, J.; García, B.; Garfias, F.; Guisa, G.; Granados, F.; Luna, E.; Martínez, B.; Michel, R.; Murillo, F.; Murillo, J.; Quechol, S.; Quiroz, F.; Tejada, C.

    2008-07-01

    The structure of the spectrograph ESOPO is the stiff mount that will maintain fixed all optics elements, electronics and mechanical subsystems. The ESOPO spectrograph is a project of the "Instituto de Astronomia de la Universidad Nacional Autonoma de Mexico" (IAUNAM) to upgrade its 2.1m telescope as a competitive facility for the next decade. The scientific purpose is to obtain a modern high efficient intermediate-low dispersion spectrograph optimized for the 3500 - 9000 Å spectral interval with a spectral resolution of 500 <= R <= 5000. It is to be used at the cassegrain f/7.5 focus of the 2.1 m telescope for general astronomical purposes. This work presents the mechanical design process and the form in which the structure was verified to comply with the ESOPO's top level image quality and stability requirements. The latter was not a lineal process. The way we resolved it is to run FEAs on the complete system and with the instrument in different operation positions during a normal cycle of observations. These results are validated through the error budget of the ESOPO. The structure is currently under construction.

  8. Ruin and Revolution in ``Hamlet."

    NASA Astrophysics Data System (ADS)

    Usher, P. D.

    1999-05-01

    In the cosmic allegorical interpretation of Shakespeare's "Hamlet" (BAAS 28, 859 & 1305, 1996; Mercury 26:1, 20, 1997; RPS 18:3, 6, 1997; Giornale di Astronomia 24:3, 27, 1998), the usurper King Claudius, namesake of Ptolemy, personifies geocentricity. Textual support for this reading is found in 1.2 where Hamlet is associated with the Sun, as befits a rightful heir, while Claudius is associated with the Earth. In 3.3 Claudius fears Hamlet's antics. Rosencrantz states that the lives of many depend on the well-being of the King. He warns that if the King were to be imperiled, his subjects, those "ten thousand lesser things", would fall in a "boisterous ruin" along with "each small annexment" and "petty consequence." These 10,000 lesser lights are the naked eye stars (mv ~ 6.5) which would collapse with the demise of the pre-Diggesian firmament, along with ancient planets and their geometrical contrivances. In 5.1 Shakespeare puns on "De revolutionibus" when he refers to "fine revolution." The double meaning of "revolution" (alteration, orbital motion) was in use long before 1600. Since "revolution" is used in the context of digging, it may refer as much to the Diggesian as the Copernican Revolution. Shakespeare's prescience is revealed by his anticipation of change, as encapsulated geocentricity is transformed to stellar boundlessness, while his presence is suggested by fatherly concerns and ghost-like direction.

  9. VizieR Online Data Catalog: Three editions of the star catalogue of Tycho Brahe. Machine-readable versions and comparison with the modern Hipparcos Catalogue.

    NASA Astrophysics Data System (ADS)

    Verbunt, F.; van Gent, R. H.

    2010-03-01

    We present in three data files the Machine-readable versions of three editions of Tycho Brahe's star catalogue. The main file KeplerE.dat contains the catalogue as published by Kepler in 1627 as part of the Tabulae Rudolphinae, with some emendations. The second file Variants.dat contains the data from other editions if different from the data in KeplerE.dat. These other editions are i) the Manuscript version of Brahe from 1598, as published by Dreyer in the Tychonis Brahe Dani Opera Omnia Vol. III (Kopenhagen, 1916), ii) the shorter version published by Brahe In the Astronomiae Instauratae Progymnasmata (1602), iii) the original (i.e. not emended) edition by Kepler (1627), iv) variants given by Kepler (1627) as `meus catalogus' or as `Piserus'. In addition to the data from the Historical catalogue, the machine-readable version contain the modern identification with a Hipparcos star and the latter's magnitude, and based on this identification the positional accuracy. The third file Names.dat contains the latin descriptions of the stars as given in Brahe's manuscript version (1598). (3 data files).

  10. Results from the Prototype GLOBE at Night Worldwide Light Pollution Observation Program

    NASA Astrophysics Data System (ADS)

    Walker, Constance E.; Pompea, S. M.; Isbell, D.; Orellana, D.; Blurton, C.; Henderson, S.

    2006-06-01

    Students, families, and educators worldwide participated in GLOBE at Night - an international event designed to observe and record the visible stars as a means of measuring light pollution in a given location. Participation was open to anyone - anywhere in the world - who could get outside and look skyward during the week of March 22-29, 2006. Our goal was 5000 observations from around the world in this prototype program.The hands-on learning activities associated with the program were designed to extend the traditional classroom and school day with a week of nighttime observations involving teachers, students and their families. By locating specific constellations in the sky, students from around the world learned how the lights in their community contribute to light pollution. Students explored the different light sources in their community learning the relationship between science, technology and society, and they reported their observations online through a central database allowing for authentic worldwide research and analysis. The observations made during GLOBE at Night helped students and scientists together assess how the quality of the night sky varies around the world as well as the level of energy wastage associated with poorly-shielded lights.For more information, visit http://www.globe.gov/globeatnight.GLOBE at Night is a collaboration between The GLOBE Program, the National Optical Astronomy Observatory (NOAO), Centro de Apoyo a la Didactica de la Astronomia (CADIAS) in Chile , Windows to the Universe, and Environmental Systems Research Institute, Inc. (ESRI).

  11. Cometas: Das Lendas aos Fatos

    NASA Astrophysics Data System (ADS)

    Voelzke, M. R.

    O descobrimento de cometas, devido ao seu aparecimento espetacular, tem registro nas mais antigas culturas humanas. A primeira referência situa-se no ano de 1095 antes de Cristo [a.C.; HO; HO, 1962]. A quantidade de registros de descobrimentos cometários, principalmente provenientes do território chinês em particular e do oriente em geral, aumentou gradualmente a partir do quarto século depois de Cristo (d.C.). É de origem chinesa a primeira referência ao cometa P/Halley no ano de 240 a.C. [VOELZKE, 1993]. Com o desenvolvimento da astronomia relativamente às técnicas observacionais os descobrimentos bem como as observações cometárias aumentaram sensivelmente a partir do século XVII, sendo que a partir do século XIX um novo incremento ocorreu devido ao emprego da fotografia e a resultante melhora de sensibilidade na observação.

  12. The Crystallography of Quasicrystals

    NASA Astrophysics Data System (ADS)

    Rabson, David Alan

    A century ago, E. S. Fedorov, A. Schonflies, and W. Barlow, working independently, classified the 230 distinct symmetry groups of objects repeated periodically in three-dimensional space. The 230 space groups determine the symmetries of macroscopic properties and provide crystallographers with their most important tool in deducing structure; as such, they find use in biology, organic chemistry, and virology as well as in physics, geology, and materials science. With the discovery in 1984 of quasicrystals, well-ordered but aperiodic metallic alloys with crystallographically forbidden rotational symmetries, the need arose to develop a space-group theory for these new materials. Based on the work by Rokhsar, Wright, and Mermin^1 in two dimensions, Rabson, Mermin, Rokhsar, and Wright have classified all quasicrystal and crystal three -dimensional axial space groups.^2 Our classification, proceeding in reciprocal space, is elementary, does not rely on projecting higher-dimensional crystallographic space groups, and is valid for arbitrary rotational symmetry. As an additional illustration of quasicrystallographic space groups, I derive and demonstrate algorithms that produce two-dimensional tilings of rhombi with each of the possible plane-group symmetries.^3 While the analogous task for crystallographic plane groups is trivial, the lack of translational symmetry in a quasicrystal tiling makes these constructions interesting. Since the symmetry of a quasicrystal appears more naturally in reciprocal than in direct space, it is not surprising that some of the resulting tilings seem intricate, although in fact their symmetries are quite simple. ftn^1 Acta Cryst. A44, 197-211 (1988). ^2 "The Space Groups of Axial Crystals and Quasicrystals," preprint. ^3See also Rabson, Ho, and Mermin, Acta Cryst. A44, 678 (1988) and Acta Cryst. A45, 538 (1989).

  13. Nanoscale Structure at Mineral-Fluid Interfaces

    NASA Astrophysics Data System (ADS)

    Sturchio, N. C.; Sturchio, N. C.; Fenter, P.; Cheng, L.; Park, C.; Zhang, Z.; Zhang, Z.; Nagy, K. L.; Schlegel, M. L.

    2001-12-01

    The nature of nanoparticles and their role in the natural environment is currently a subject of renewed interest. The high surface area (and surface area-to-volume ratio) of nanoparticles exerts a widespread influence on geochemical reactions and transport processes. A thorough understanding of the nanoscale world remains largely hypothetical, however, because of the challenges associated with characterizing nanoscale structures and processes. Recent insights gained from high-resolution synchrotron x-ray reflectivity measurements at the solid-fluid interfaces of macroscopic (i.e., mm-scale) mineral particles may provide relevant guidelines for expected nanoparticle surface structures. For example, at calcite-water and barite-water interfaces, undercoordinated surface cations bond with water species of variable protonation, and modest relaxations (to several hundredths of a nanometer) affect the outermost unit cells [1,2]. Undercoordinated tetrahedral ions at aluminosilicate surfaces also bond with water species, whereas interstitial or interlayer alkali or alkaline earth ions at the surface may readily exchange with hydronium or other ions; modest relaxations also affect the outermost unit cells [3,4]. Modulation of liquid water structure out to about one nanometer has been observed at the (001) cleavage surface of muscovite in deionized water, and may be present at other mineral-fluid interfaces [4]. Dissolution mechanisms at the orthoclase-water interface have been clarified by combining x-ray reflectivity and scanning force microscopy measurements [5]. Further progress in understanding nanoscale structures and processes at macroscopic mineral-water interfaces is likely to benefit nanoparticle studies. [1] Fenter et al. (2000) Geochim. Cosmochim. Acta 64, 1221-1228. [2] Fenter et al. (2001) J. Phys. Chem. B 105(34), 8112-8119. [3] Fenter et al. (2000) Geochim. Cosmochim. Acta 64, 3663-3673. [4] Cheng et al. (2001) Phys. Rev. Lett., (in press). [5] Teng et al

  14. Nemaline myopathy caused by mutations in the muscle alpha-skeletal-actin gene.

    PubMed

    Ilkovski, B; Cooper, S T; Nowak, K; Ryan, M M; Yang, N; Schnell, C; Durling, H J; Roddick, L G; Wilkinson, I; Kornberg, A J; Collins, K J; Wallace, G; Gunning, P; Hardeman, E C; Laing, N G; North, K N

    2001-06-01

    Nemaline myopathy (NM) is a clinically and genetically heterogeneous disorder characterized by muscle weakness and the presence of nemaline bodies (rods) in skeletal muscle. Disease-causing mutations have been reported in five genes, each encoding a protein component of the sarcomeric thin filament. Recently, we identified mutations in the muscle alpha-skeletal-actin gene (ACTA1) in a subset of patients with NM. In the present study, we evaluated a new series of 35 patients with NM. We identified five novel missense mutations in ACTA1, which suggested that mutations in muscle alpha-skeletal actin account for the disease in approximately 15% of patients with NM. The mutations appeared de novo and represent new dominant mutations. One proband subsequently had two affected children, a result consistent with autosomal dominant transmission. The seven patients exhibited marked clinical variability, ranging from severe congenital-onset weakness, with death from respiratory failure during the 1st year of life, to a mild childhood-onset myopathy, with survival into adulthood. There was marked variation in both age at onset and clinical severity in the three affected members of one family. Common pathological features included abnormal fiber type differentiation, glycogen accumulation, myofibrillar disruption, and "whorling" of actin thin filaments. The percentage of fibers with rods did not correlate with clinical severity; however, the severe, lethal phenotype was associated with both severe, generalized disorganization of sarcomeric structure and abnormal localization of sarcomeric actin. The marked variability, in clinical phenotype, among patients with different mutations in ACTA1 suggests that both the site of the mutation and the nature of the amino acid change have differential effects on thin-filament formation and protein-protein interactions. The intrafamilial variability suggests that alpha-actin genotype is not the sole determinant of phenotype. PMID:11333380

  15. Myc Potentiates Apoptosis by Stimulating Bax Activity at the Mitochondria†

    PubMed Central

    Soucie, Erinn L.; Annis, Matthew G.; Sedivy, John; Filmus, Jorge; Leber, Brian; Andrews, David W.; Penn, Linda Z.

    2001-01-01

    The ability of the c-Myc oncoprotein to potentiate apoptosis has been well documented; however, the mechanism of action remains ill defined. We have previously identified spatially distinct apoptotic pathways within the same cell that are differentially inhibited by Bcl-2 targeted to either the mitochondria (Bcl-acta) or the endoplasmic reticulum (Bcl-cb5). We show here that in Rat1 cells expressing an exogenous c-myc allele, distinct apoptotic pathways can be inhibited by Bcl-2 or Bcl-acta yet be distinguished by their sensitivity to Bcl-cb5 as either susceptible (serum withdrawal, taxol, and ceramide) or refractory (etoposide and doxorubicin). Myc expression and apoptosis were universally associated with Bcl-acta and not Bcl-cb5, suggesting that Myc acts downstream at a point common to these distinct apoptotic signaling cascades. Analysis of Rat1 c-myc null cells shows these same death stimuli induce apoptosis with characteristic features of nuclear condensation, membrane blebbing, poly (ADP-ribose) polymerase cleavage, and DNA fragmentation; however, this Myc-independent apoptosis is not inhibited by Bcl-2. During apoptosis, Bax translocation to the mitochondria occurs in the presence or absence of Myc expression. Moreover, Bax mRNA and protein expression remain unchanged in the presence or absence of Myc. However, in the absence of Myc, Bax is not activated and cytochrome c is not released into the cytoplasm. Reintroduction of Myc into the c-myc null cells restores Bax activation, cytochrome c release, and inhibition of apoptosis by Bcl-2. These results demonstrate a role for Myc in the regulation of Bax activation during apoptosis. Moreover, apoptosis that can be triggered in the absence of Myc provides evidence that signaling pathways exist which circumvent Bax activation and cytochrome c release to trigger caspase activation. Thus, Myc increases the cellular competence to die by enhancing disparate apoptotic signals at a common mitochondrial amplification

  16. An examination of the regulatory mechanism of Pxdn mutation-induced eye disorders using microarray analysis

    PubMed Central

    YANG, YANG; XING, YIQIAO; LIANG, CHAOQUN; HU, LIYA; XU, FEI; MEI, QI

    2016-01-01

    The present study aimed to identify biomarkers for peroxidasin (Pxdn) mutation-induced eye disorders and study the underlying mechanisms involved in this process. The microarray dataset GSE49704 was used, which encompasses 4 mouse samples from embryos with Pxdn mutation and 4 samples from normal tissues. After data preprocessing, the differentially expressed genes (DEGs) between Pxdn mutation and normal tissues were identified using the t-test in the limma package, followed by functional enrichment analysis. The protein-protein interaction (PPI) network was constructed based on the STRING database, and the transcriptional regulatory (TR) network was established using the GeneCodis database. Subsequently, the overlapping DEGs with high degrees in two networks were identified, as well as the sub-network extracted from the TR network. In total, 121 (75 upregulated and 46 downregulated) DEGs were identified, and these DEGs play important roles in biological processes (BPs), including neuron development and differentiation. A PPI network containing 25 nodes such as actin, alpha 1, skeletal muscle (Acta1) and troponin C type 2 (fast) (Tnnc2), and a TR network including 120 nodes were built. By comparing the two networks, seven crucial genes which overlapped were identified, including cyclin-dependent kinase inhibitor 1B (Cdkn1b), Acta1 and troponin T type 3 (Tnnt3). In the sub-network, Cdkn1b was predicted as the target of miRNAs such as mmu-miR-24 and transcription factors (TFs) including forkhead box O4 (FOXO4) and activating enhancer binding protein 4 (AP4). Thus, we suggest that seven crucial genes, including Cdkn1b, Acta1 and Tnnt3, play important roles in the progression of eye disorders such as glaucoma. We suggest that Cdkn1b exert its effects via the inhibition of proliferation and is mediated by mmu-miR-24 and targeted by the TFs FOXO4 and AP4. PMID:27121343

  17. Meta-analysis as Statistical and Analytical Method of Journal’s Content Scientific Evaluation

    PubMed Central

    Masic, Izet; Begic, Edin

    2015-01-01

    Introduction: A meta-analysis is a statistical and analytical method which combines and synthesizes different independent studies and integrates their results into one common result. Goal: Analysis of the journals “Medical Archives”, “Materia Socio Medica” and “Acta Informatica Medica”, which are located in the most eminent indexed databases of the biomedical milieu. Material and methods: The study has retrospective and descriptive character, and included the period of the calendar year 2014. Study included six editions of all three journals (total of 18 journals). Results: In this period was published a total of 291 articles (in the “Medical Archives” 110, “Materia Socio Medica” 97, and in “Acta Informatica Medica” 84). The largest number of articles was original articles. Small numbers have been published as professional, review articles and case reports. Clinical events were most common in the first two journals, while in the journal “Acta Informatica Medica” belonged to the field of medical informatics, as part of pre-clinical medical disciplines. Articles are usually required period of fifty to fifty nine days for review. Articles were received from four continents, mostly from Europe. The authors are most often from the territory of Bosnia and Herzegovina, then Iran, Kosovo and Macedonia. Conclusion: The number of articles published each year is increasing, with greater participation of authors from different continents and abroad. Clinical medical disciplines are the most common, with the broader spectrum of topics and with a growing number of original articles. Greater support of the wider scientific community is needed for further development of all three of the aforementioned journals. PMID:25870484

  18. Potential Role of Glycogen Synthase Kinase-3β in Regulation of Myocardin Activity in Human Vascular Smooth Muscle Cells.

    PubMed

    Zhou, Yi-Xia; Shi, Zhan; Singh, Pavneet; Yin, Hao; Yu, Yan-Ni; Li, Long; Walsh, Michael P; Gui, Yu; Zheng, Xi-Long

    2016-02-01

    Glycogen synthase kinase (GSK)-3β, a serine/threonine kinase with an inhibitory role in glycogen synthesis in hepatocytes and skeletal muscle, is also expressed in cardiac and smooth muscles. Inhibition of GSK-3β results in cardiac hypertrophy through reducing phosphorylation and increasing transcriptional activity of myocardin, a transcriptional co-activator for serum response factor. Myocardin plays critical roles in differentiation of smooth muscle cells (SMCs). This study, therefore, aimed to examine whether and how inhibition of GSK-3β regulates myocardin activity in human vascular SMCs. Treatment of SMCs with the GSK-3β inhibitors AR-A014418 and TWS 119 significantly reduced endogenous myocardin activity, as indicated by lower expression of myocardin target genes (and gene products), CNN1 (calponin), TAGLN1 (SM22), and ACTA2 (SM α-actin). In human SMCs overexpressing myocardin through the T-REx system, treatment with either GSK-3β inhibitor also inhibited the expression of CNN1, TAGLN1, and ACTA2. These effects of GSK-3β inhibitors were mimicked by transfection with GSK-3β siRNA. Notably, both AR-A014418 and TWS 119 decreased the serine/threonine phosphorylation of myocardin. The chromatin immunoprecipitation assay showed that AR-A014418 treatment reduced myocardin occupancy of the promoter of the myocardin target gene ACTA2. Overexpression of a dominant-negative GSK-3β mutant in myocardin-overexpressing SMCs reduced the expression of calponin, SM22, and SM α-actin. As expected, overexpression of constitutively active or wild-type GSK-3β in SMCs without myocardin overexpression increased expression of these proteins. In summary, our results indicate that inhibition of GSK-3β reduces myocardin transcriptional activity, suggesting a role for GSK-3β in myocardin transcriptional activity and smooth muscle differentiation. PMID:26129946

  19. Autocrine production of TGF-β1 promotes myofibroblastic differentiation of neonatal lung mesenchymal stem cells

    PubMed Central

    Popova, Antonia P.; Bozyk, Paul D.; Goldsmith, Adam M.; Linn, Marisa J.; Lei, Jing; Bentley, J. Kelley

    2010-01-01

    We have isolated mesenchymal stem cells (MSCs) from tracheal aspirates of premature infants with respiratory distress. We examined the capacity of MSCs to differentiate into myofibroblasts, cells that participate in lung development, injury, and repair. Gene expression was measured by array, qPCR, immunoblot, and immunocytochemistry. Unstimulated MSCs expressed mRNAs encoding contractile (e.g., ACTA2, TAGLN), extracellular matrix (COL1A1 and ELN), and actin-binding (DBN1, PXN) proteins, consistent with a myofibroblast phenotype, although there was little translation into immunoreactive protein. Incubation in serum-free medium increased contractile protein (ACTA2, MYH11) gene expression. MSC-conditioned medium showed substantial levels of TGF-β1, and treatment of serum-deprived cells with a type I activin receptor-like kinase inhibitor, SB-431542, attenuated the expression of genes encoding contractile and extracellular matrix proteins. Treatment of MSCs with TGF-β1 further induced the expression of mRNAs encoding contractile (ACTA2, MYH11, TAGLN, DES) and extracellular matrix proteins (FN1, ELN, COL1A1, COL1A2), and increased the protein expression of α-smooth muscle actin, myosin heavy chain, and SM22. In contrast, human bone marrow-derived MSCs failed to undergo TGF-β1-induced myofibroblastic differentiation. Finally, primary cells from tracheal aspirates behaved in an identical manner as later passage cells. We conclude that human neonatal lung MSCs demonstrate an mRNA expression pattern characteristic of myofibroblast progenitor cells. Autocrine production of TGF-β1 further drives myofibroblastic differentiation, suggesting that, in the absence of other signals, fibrosis represents the “default program” for neonatal lung MSC gene expression. These data are consistent with the notion that MSCs play a key role in neonatal lung injury and repair. PMID:20190033

  20. Density- and wavefunction-normalized Cartesian spherical harmonics for l ≤ 20.

    PubMed

    Michael, J Robert; Volkov, Anatoliy

    2015-03-01

    The widely used pseudoatom formalism [Stewart (1976). Acta Cryst. A32, 565-574; Hansen & Coppens (1978). Acta Cryst. A34, 909-921] in experimental X-ray charge-density studies makes use of real spherical harmonics when describing the angular component of aspherical deformations of the atomic electron density in molecules and crystals. The analytical form of the density-normalized Cartesian spherical harmonic functions for up to l ≤ 7 and the corresponding normalization coefficients were reported previously by Paturle & Coppens [Acta Cryst. (1988), A44, 6-7]. It was shown that the analytical form for normalization coefficients is available primarily for l ≤ 4 [Hansen & Coppens, 1978; Paturle & Coppens, 1988; Coppens (1992). International Tables for Crystallography, Vol. B, Reciprocal space, 1st ed., edited by U. Shmueli, ch. 1.2. Dordrecht: Kluwer Academic Publishers; Coppens (1997). X-ray Charge Densities and Chemical Bonding. New York: Oxford University Press]. Only in very special cases it is possible to derive an analytical representation of the normalization coefficients for 4 < l ≤ 7 (Paturle & Coppens, 1988). In most cases for l > 4 the density normalization coefficients were calculated numerically to within seven significant figures. In this study we review the literature on the density-normalized spherical harmonics, clarify the existing notations, use the Paturle-Coppens (Paturle & Coppens, 1988) method in the Wolfram Mathematica software to derive the Cartesian spherical harmonics for l ≤ 20 and determine the density normalization coefficients to 35 significant figures, and computer-generate a Fortran90 code. The article primarily targets researchers who work in the field of experimental X-ray electron density, but may be of some use to all who are interested in Cartesian spherical harmonics. PMID:25727874

  1. A monoclinic form of dendocarbin A: a borderline case of one-dimensional isostructural polymorphism.

    PubMed

    Paz, Cristian; Burgos, Viviana; Suarez, Sebastián; Baggio, Ricardo

    2015-04-01

    The title compound, dendocarbin A [systematic name: (1R,5aS,9aS,9bR)-1-hydroxy-6,6,9a-trimethyldodecahydronaphtho[1,2-c]furan-3-one], C15H22O3, is a sesquiterpene lactone isolated from Drimys winteri var chilensis. The monoclinic phase described herein displays an identical molecular structure to the orthorhombic phase that we reported previously [Paz Robles et al. (2014). Acta Cryst. C70, 1007-1010], while varying significantly in chain pitch, and can thus be considered as a borderline case of one-dimensional isostructural polymorphism. PMID:25836288

  2. Second-order Optimality Conditions for Optimal Control of the Primitive Equations of the Ocean with Periodic Inputs

    SciTech Connect

    Tachim Medjo, T.

    2011-02-15

    We investigate in this article the Pontryagin's maximum principle for control problem associated with the primitive equations (PEs) of the ocean with periodic inputs. We also derive a second-order sufficient condition for optimality. This work is closely related to Wang (SIAM J. Control Optim. 41(2):583-606, 2002) and He (Acta Math. Sci. Ser. B Engl. Ed. 26(4):729-734, 2006), in which the authors proved similar results for the three-dimensional Navier-Stokes (NS) systems.

  3. Discovery of a meta-stable Al–Sm phase with unknown stoichiometry using a genetic algorithm

    SciTech Connect

    Zhang, Feng; McBrearty, Ian; Ott, R T; Park, E; Mendelev, Mikhail I; Kramer, M J; Wang, Cai-Zhuang; Ho, Kai-Ming

    2014-06-01

    Unknown crystalline phases observed during the devitrification process of glassy metal alloys significantly limit our ability to understand and control phase selection in these systems driven far from equilibrium. Here, we report a new meta-stable Al5Sm phase identified by simultaneously searching Al-rich compositions of the Al-Sm system, using an efficient genetic algorithm. The excellent match between calculated and experimental X-ray diffraction patterns confirms that this new phase appeared in the crystallization of melt-spun Al90Sm10 alloys. Published by Elsevier Ltd. on behalf of Acta Materialia Inc.

  4. The Local Orthogonality Between Quantum States and Entanglement Decomposition

    NASA Astrophysics Data System (ADS)

    Kim, Sunho; Wu, Junde; Zhang, Lin; Cho, Minhyung

    2016-06-01

    In the paper, we show that when a quantum state can be decomposed as a convex combination of locally orthogonal mixed states, its entanglement can be decomposed into the entanglement of these mixed states without losing them. The obtained result generalizes a corresponding one proved by Horodecki (Acta Phys. Slov. 48, 141 1998). But, for the entanglement cost it requires certain conditions for holding the decomposition, and the distillable entanglement only has a week result as inequality. Finally, we presented an example to show that the conditions of our conclusions are existence.

  5. (E)-Ethyl 3-(3,4-dihydroxyphenyl)prop-2-enoate: a natural polymorph extracted from Aristotelia chilensis (Maqui).

    PubMed

    Paz, Cristian; Moreno, Yanko; Becerra, José; Silva, Mario; Burgos, Viviana; Freire, Eleonora; Baggio, Ricardo

    2013-07-01

    The natural title compound, C11H12O4, extracted from the Chilean native tree Aristotelia chilensis (Maqui), is a polymorph of the synthetic E form reported by Xia, Hu & Rao [Acta Cryst. (2004), E60, o913-o914]. Both rotational conformers are identical from a metrical point of view, and only differ in the orientation of the 3,4-dihydroxyphenyl ring with respect to the rest of the molecule, which leads to completely different crystal structure arrangements and packing efficiencies. The reasons behind both reside in the different hydrogen-bonding interactions. PMID:23832039

  6. On the effective ionic radii for ammonium.

    PubMed

    Sidey, Vasyl

    2016-08-01

    A set of effective ionic radii corresponding to different coordination numbers (CNs) and compatible with the radii system by Shannon [Acta Cryst. (1976), A32, 751-767] has been derived for ammonium: 1.40 Å (CN = IV), 1.48 Å (CN = VI), 1.54 Å (CN = VIII) and 1.67 Å (CN = XII). The bond-valence parameters r0 = 2.3433 Å and B = 0.262 Å have been determined for ammonium-fluorine bonds. PMID:27484382

  7. The application of eigensymmetries of face forms to X-ray diffraction intensities of crystals twinned by `reticular merohedry'

    NASA Astrophysics Data System (ADS)

    Klapper, H.; Hahn, Th

    2012-01-01

    Crystallographic face forms {hkl} are interpreted as sets of symmetry-equivalent X-ray reflections. Extending an earlier paper on twinning by merohedry [ [Sigma] = 1, Klapper & Hahn (2010). Acta Cryst. A66, 327-346], the eigensymmetry of these forms is used to derive general relations between the diffraction intensities of overlapping twin-related reflections. The following twins by reticular merohedry are treated: [Sigma] 3 twins of rhombohedral and cubic, [Sigma] 5 twins of tetragonal and [Sigma] 7 twins of hexagonal crystals.

  8. Aortic Aneurysm: Etiopathogenesis and Clinicopathologic Correlations

    PubMed Central

    2016-01-01

    Aortic aneurysm (AA) is one of the life-threatening aortic diseases, leading to aortic rupture of any cause including atherosclerotic and non-atherosclerotic diseases. AA is diagnosed in a variable proportion of patients with dilated aorta by imaging modality. The etiopathogenesis of AA remains unclear in many aortic diseases. Furthermore, although it may be difficult to explain all phenotypes of patients even if genetic mutation could be identified in some proteins such as smooth muscle cell α-actin (ACTA2), myosin heavy chain 11 (MYH11) or SMAD3, individualized consideration of these factors in each patient is essential on the basis of clinicopathological characteristics. PMID:27375798

  9. Comparison of beetroot extracts originating from several sites using time-resolved laser-induced fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Rabasović, M. S.; Šević, D.; Terzić, M.; Marinković, B. P.

    2012-05-01

    Beetroot (Beta vulgaris) juice contains a large number of fluorophores which can fluoresce. There is a growing interest in beetroot extracts analysis. In contrast, there is only limited information about beetroot obtained without sample preparation and/or extraction of components from the sample. In this work, we continue our previous study (Rabasović et al 2009 Acta Phys. Pol. A 116 570-2), analyzing and comparing beetroot extracts from several sites, using the time-resolved laser-induced fluorescence technique to measure the fluorescence of samples at different excitation wavelengths (340-470 nm) and for different sample dilutions.

  10. GENERAL: Efficient quantum secure communication with a publicly known key

    NASA Astrophysics Data System (ADS)

    Li, Chun-Yan; Li, Xi-Han; Deng, Fu-Guo; Zhou, Hong-Yu

    2008-07-01

    This paper presents a simple way for an eavesdropper to eavesdrop freely the secret message in the experimental realization of quantum communication protocol proposed by Beige et al (2002 Acta Phys. Pol. A 101 357). Moreover, it introduces an efficient quantum secure communication protocol based on a publicly known key with decoy photons and two biased bases by modifying the original protocol. The total efficiency of this new protocol is double that of the original one. With a low noise quantum channel, this protocol can be used for transmitting a secret message. At present, this protocol is good for generating a private key efficiently.

  11. The analysis of protein conformation by infrared spectroscopy: An introduction of the editor to a scientific dispute

    NASA Astrophysics Data System (ADS)

    Mäntele, Werner

    2015-03-01

    Spectrochimica Acta A is open for a vivid exchange among scientists and fosters the open discussion of published papers. This may proceed in the form of a "Comment on a published paper", submitted to our journal as a short communication. Typically, this comment will be sent to the authors of the original article to give them a chance for rebuttal in a "Reply to Comment". Both the Comment and the Reply will be published together in one issue after review by experts. In the interest of a fair discussion, both contributions will eventually have to undergo some editing before publication can be made.

  12. A Multiparty Controlled Bidirectional Quantum Secure Direct Communication and Authentication Protocol Based on EPR Pairs

    NASA Astrophysics Data System (ADS)

    Chang, Yan; Zhang, Shi-Bin; Yan, Li-Li; Sheng, Zhi-Wei

    2013-06-01

    A multiparty controlled bidirectional quantum secure direct communication and authentication protocol is proposed based on EPR pair and entanglement swapping. The legitimate identities of communicating parties are encoded to Bell states which act as a detection sequence. Secret messages are transmitted by using the classical XOR operation, which serves as a one-time-pad. No photon with secret information transmits in the quantum channel. Compared with the protocols proposed by Wang et al. [Acta Phys. Sin. 56 (2007) 673; Opt. Commun. 266 (2006) 732], the protocol in this study implements bidirectional communication and authentication, which defends most attacks including the ‘man-in-the-middle’ attack efficiently.

  13. Critical analysis and extension of the Hirshfeld atoms in molecules.

    PubMed

    Bultinck, Patrick; Van Alsenoy, Christian; Ayers, Paul W; Carbó-Dorca, Ramon

    2007-04-14

    The computational approach to the Hirshfeld [Theor. Chim. Acta 44, 129 (1977)] atom in a molecule is critically investigated, and several difficulties are highlighted. It is shown that these difficulties are mitigated by an alternative, iterative version, of the Hirshfeld partitioning procedure. The iterative scheme ensures that the Hirshfeld definition represents a mathematically proper information entropy, allows the Hirshfeld approach to be used for charged molecules, eliminates arbitrariness in the choice of the promolecule, and increases the magnitudes of the charges. The resulting "Hirshfeld-I charges" correlate well with electrostatic potential derived atomic charges. PMID:17444705

  14. Critical analysis and extension of the Hirshfeld atoms in molecules

    NASA Astrophysics Data System (ADS)

    Bultinck, Patrick; Van Alsenoy, Christian; Ayers, Paul W.; Carbó-Dorca, Ramon

    2007-04-01

    The computational approach to the Hirshfeld [Theor. Chim. Acta 44, 129 (1977)] atom in a molecule is critically investigated, and several difficulties are highlighted. It is shown that these difficulties are mitigated by an alternative, iterative version, of the Hirshfeld partitioning procedure. The iterative scheme ensures that the Hirshfeld definition represents a mathematically proper information entropy, allows the Hirshfeld approach to be used for charged molecules, eliminates arbitrariness in the choice of the promolecule, and increases the magnitudes of the charges. The resulting "Hirshfeld-I charges" correlate well with electrostatic potential derived atomic charges.

  15. Reinvestigation of growth of urea thiosemicarbazone monohydrate crystal

    NASA Astrophysics Data System (ADS)

    Srinivasan, Bikshandarkoil R.; Raghavaiah, Pallepogu; Nadkarni, V. S.

    2013-08-01

    The reaction of urea with thiosemicarbazide in 1:1 mole ratio in aqueous solution does not result in the formation of urea thiosemicarbazone monohydrate crystal, as reported by Hanumantharao, Kalainathan and Bhagavannarayana [Spectrochim. Acta A91 (2012) 345-351]. A reinvestigation of the reported reaction reveals that the crystal obtained is the starting material namely thiosemicarbazide, which has been unambiguously confirmed with the aid of infrared and 1H NMR spectra and single crystal X-ray structure determination. Analysis of 1H NMR spectrum reveals that thiosemicarbazide exhibits thione-thiol tautomerism in solution. In contrast, thiosemicarbazide exists as the thione tautomer in the solid state.

  16. Crystal structure of benzene-1,3,5-tri-carb-oxy-lic acid-4-pyridone (1/3).

    PubMed

    Staun, Selena L; Oliver, Allen G

    2015-11-01

    Slow co-crystallization of a solution of benzene-1,3,5-tri-carb-oxy-lic acid with a large excess of 4-hy-droxy-pyridine produces an inter-penetrating, three-dimensional, hydrogen-bonded framework consisting of three 4-pyridone and one benzene-1,3,5-tri-carb-oxy-lic acid mol-ecules, C9H6O6·3C5H5NO. This structure represents an ortho-rhom-bic polymorph of the previously reported C-centered, monoclinic structure [Campos-Gaxiola et al. (2014 ▸). Acta Cryst. E70, o453-o454]. PMID:26594492

  17. On the mathematical and geometrical structure of the determining equations for shear waves in nonlinear isotropic incompressible elastodynamics

    NASA Astrophysics Data System (ADS)

    Saccomandi, Giuseppe; Vitolo, Raffaele

    2014-08-01

    Using the theory of 1 + 1 hyperbolic systems we put in perspective the mathematical and geometrical structure of the celebrated circularly polarized waves solutions for isotropic hyperelastic materials determined by Carroll [Acta Mechanica 3, 167-181 (1967)]. We show that a natural generalization of this class of solutions yields an infinite family of linear solutions for the equations of isotropic elastodynamics. Moreover, we determine a huge class of hyperbolic partial differential equations having the same property of the shear wave system. Restricting the attention to the usual first order asymptotic approximation of the equations determining transverse waves we provide the complete integration of this system using generalized symmetries.

  18. Redetermination of tetra­kis(N,N-diethyl­dithio­carbamato)tin(IV)

    PubMed Central

    Okio, Coco K. Y. A.; Speziali, Nivaldo L.

    2009-01-01

    The crystal structure of the title compound, [Sn(C5H10NS2)4], was originally determined by Harreld & Schlemper [Acta Cryst. (1971), B27, 1964–1969] using intensity data estimated from Weissenberg films. In comparison with the previous refinement, the current redetermination reveals anisotropic displacement parameters for all non-H atoms, localization of the H atoms, and higher precision of lattice parameters and inter­atomic distances. The complex features a distorted S6 octa­hedral coordination geometry for tin and a cis disposition of the monodentate dithio­carbamate ligands. PMID:21583036

  19. Use of an alumina column in estimating total iron-binding capacity.

    PubMed

    Starr, R T

    1980-01-01

    I describe a simple, rapid technique for saturating the transferrin in serum and then removing unbound (excess) iron. This technique involves use of an easily prepared column of basic chromatographic alumina and a saturating solution of ferric chloride in citric acid. This method, when compared with the magnesium carbonate method of Ramsay (Clin. Chim. Acta 2: 221, 1957) by regression analysis and tests of precision, showed a negative bias for results by the alumina technique with respect to the magnesium carbonate method. PMID:7356553

  20. RbZnFe(PO4)2: synthesis and crystal structure

    PubMed Central

    Badri, Abdessalem; Ben Amara, Mongi

    2016-01-01

    A new iron phosphate, rubidium zinc iron(III) phosphate, RbZnFe(PO4)2, has been synthesized as single crystals by the flux method. This compound is isostructural to the previously reported KCoAl(PO4)2 [Chen et al. (1997 ▸). Acta Cryst. C53,1754–1756]. Its structure consists of a three-dimensional framework built up from corner-sharing PO4 and (Zn,Fe)O4 tetra­hedra. This mode of linkage forms channels parallel to the [100], [010] and [001] directions in which the Rb+ ions are located. PMID:27536385

  1. Reaustenitization in Fe-C steels revisited

    SciTech Connect

    Mancini, R.; Budde, C.

    1999-08-10

    A finite difference method used in order to model the reaustenitization from a ferrite/cementite mixture in Fe-C steels is presented in this paper. The numerical results obtained are compared with the exact solution of the diffusion equion that describes the process for the planar geometry. The agreement between both methods is excellent in a large range of temperatures. Incidentally, the authors consider worth noting that the second moment of mass condition used by Akbay et al. [Acta Metallurgica et Materialia 47, 1649 (1994)] does not seem to be necessary in the framework of the numerical method. Finally, they compare their results with available experimental values finding good agreement.

  2. Comment on "Density functional theory studies on molecular structure, vibrational spectra and electronic properties of cyanuric acid".

    PubMed

    Reva, Igor

    2015-12-01

    In a recently published paper [Spectrochim. Acta A: Mol. Biomol. Spect. 138 (2015) 711-722], Prabhaharan, Prabakaran, Srinivasan, and Gunasekaran presented a combined experimental and theoretical study on molecular structure, vibrational spectra and NBO analysis of cyanuric acid, and explain their findings using the tri-hydroxy tautomeric form of the compound. In reality, the compound adopts the tri-oxo tautomeric form, which is by over 100kJmol(-1) more stable comparatively to the tri-hydroxy tautomer discussed and characterized by Prabhaharan et al. PMID:26142656

  3. Infantile hypophosphatasia without bone deformities presenting with severe pyridoxine-resistant seizures.

    PubMed

    de Roo, Marieke G A; Abeling, Nico G G M; Majoie, Charles B; Bosch, Annet M; Koelman, Johannes H T M; Cobben, Jan M; Duran, Marinus; Poll-The, Bwee Tien

    2014-03-01

    An infant carrying a heterozygous c.43_46delACTA and a heterozygous c.668 G>A mutation in the ALPL gene with hypophosphatasia in the absence of bone deformities presented with therapy-resistant seizures. Pyridoxal phosphate was extremely high in CSF and plasma. Pyridoxine treatment had only a transient effect and the severe encephalopathy was fatal. Repeated brain MRIs showed progressive cerebral damage. The precise metabolic cause of the seizures remains unknown and pyridoxine treatment apparently does not cure the epilepsy. PMID:24100244

  4. Spherical nanoindentation stress-strain curves of commercially pure titanium and Ti-6Al-4V

    DOE Data Explorer

    Weaver, Jordan S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Priddy, Matthew W. [Georgia Inst. of Technology, Atlanta, GA (United States); McDowell, David L. [Georgia Inst. of Technology, Atlanta, GA (United States); Kalidindi, Surya R. [Georgia Inst. of Technology, Atlanta, GA (United States)

    2016-07-27

    Spherical nanoindentation combined with electron back-scattered diffraction was employed to characterize the grain-scale elastic and plastic anisotropy of single crystal alpha-Ti for commercially pure (CP-Ti) and alloyed (Ti-64) titanium. In addition, alpha-beta Ti (single colony) grains were characterized. The data set includes the nanoindentation force, displacement, and contact stiffness, the nanoindentation stress-strain analysis, and the alpha-Ti crystal orientations. Details of the samples and experimental protocols can be found in Weaver et al. (2016) Acta Materialia doi:10.1016/j.actamat.2016.06.053.

  5. Statistical thermodynamics of strain hardening in polycrystalline solids

    NASA Astrophysics Data System (ADS)

    Langer, J. S.

    2015-09-01

    This paper starts with a systematic rederivation of the statistical thermodynamic equations of motion for dislocation-mediated plasticity proposed in 2010 by Langer, Bouchbinder, and Lookman [Acta Mat. 58, 3718 (2010), 10.1016/j.actamat.2010.03.009]. It then uses that theory to explain the anomalous rate-hardening behavior reported in 1988 by Follansbee and Kocks and to explore the relation between hardening rate and grain size reported in 1995 by Meyers et al. A central theme is the need for physics-based, nonequilibrium analyses in developing predictive theories of the strength of polycrystalline materials.

  6. Sediment transport mechanics

    NASA Astrophysics Data System (ADS)

    Ballio, Francesco; Tait, Simon

    2012-12-01

    The Editor of Acta Geophysica and the Guest Editors wish to dedicate this Topical Issue on Sediment Transport Mechanics to the memory of Stephen Coleman, who died recently. During his career, Stephen had made an outstanding scientific contribution to the topic of Sediment Transport. The level of his contribution is demonstrated in the paper by Aberle, Coleman, and Nikora included in this issue, on which he started working before becoming aware of the illness that led to his untimely death. For scholars and colleagues Stephen remains an example of intellectual honesty and scientific insight.

  7. An amino-imino resonance study of 2-amino-4-methylpyridinium nitrate and 2-amino-5-methylpyridinium nitrate.

    PubMed

    Yan, Xing-Chen; Fan, Yu-Hua; Bi, Cai-Feng; Zhang, Xia; Zhang, Zhong-Yu

    2013-01-01

    The contributions of the amino and imino resonance forms to the ground-state structures of 2-amino-4-methylpyridinium nitrate, C(6)H(9)N(2)(+)·NO(3)(-), and the previously reported 2-amino-5-methylpyridinium nitrate [Yan, Fan, Bi, Zuo & Zhang (2012). Acta Cryst. E68, o2084], were studied using a combination of IR spectroscopy, X-ray crystallography and density functional theory (DFT). The results show that the structures of 2-amino-4-methylpyridine and 2-amino-5-methylpyridine obtained upon protonation are best described as existing largely in the imino resonance forms. PMID:23282916

  8. Structural complexity and configurational entropy of crystals.

    PubMed

    Krivovichev, Sergey V

    2016-04-01

    Using a statistical approach, it is demonstrated that the complexity of a crystal structure measured as the Shannon information per atom [Krivovichev (2012). Acta Cryst. A68, 393-398] represents a negative contribution to the configurational entropy of a crystalline solid. This conclusion is in full accordance with the general agreement that information and entropy are reciprocal variables. It also agrees well with the understanding that complex structures possess lower entropies relative to their simpler counterparts. The obtained equation is consistent with the Landauer principle and points out that the information encoded in a crystal structure has a physical nature. PMID:27048729

  9. Magmas and their sources: A special issue honoring Frederick A. Frey

    NASA Astrophysics Data System (ADS)

    Garcia, Michael O.; Rhodes, J. Michael; Huang, Shichun; Hickey-Vargas, Rosemary

    2016-07-01

    This special issue is dedicated to Frederick A. Frey (Fig. 1), a pioneer in the use of trace element geochemistry (especially the rare-earth elements, REE) to interpret the origin and evolution of basalts and andesites, peridotites, granites, meteorites, tektites and even sediments. Fred's remarkable career spans more than 5 decades starting in 1964 with his seminal paper with advisor Larry Haskin entitled "rare earths in oceanic basalts" (Frey and Haskin, 1964). Given that Fred was an Associate Editor of Geochimica et Cosmochimica Acta (GCA) for 20 years, GCA is a highly appropriate venue for this collection of twenty-seven new scientific papers in his honor.

  10. RbZnFe(PO4)2: synthesis and crystal structure.

    PubMed

    Badri, Abdessalem; Ben Amara, Mongi

    2016-08-01

    A new iron phosphate, rubidium zinc iron(III) phosphate, RbZnFe(PO4)2, has been synthesized as single crystals by the flux method. This compound is isostructural to the previously reported KCoAl(PO4)2 [Chen et al. (1997 ▸). Acta Cryst. C53,1754-1756]. Its structure consists of a three-dimensional framework built up from corner-sharing PO4 and (Zn,Fe)O4 tetra-hedra. This mode of linkage forms channels parallel to the [100], [010] and [001] directions in which the Rb(+) ions are located. PMID:27536385

  11. Trimethyl-3-meth­oxy-4-oxo-5-triphenyl­phospho­ranyl­idene­cyclo­pent-1-ene-1,2,3-tricarboxyl­ate

    PubMed Central

    Krawczyk, Krzysztof K.; Wojtasiewicz, Krystyna; Maurin, Jan K.; Gronowska, Ewa; Czarnocki, Zbigniew

    2010-01-01

    The title compound, C30H27O8P (2), was formed as one of two products {(1) [Krawczyk et al. (2010 ▶). Acta Cryst. E66 (cv2752)] and (2)} in the reaction of dimethyl acetyl­enedicarboxyl­ate with triphenyl­phosphine. The mol­ecule of (2) consists of a five-membered carbocyclic ring. The P atom is a part of a triphenylphosphoranylidene substituent. In contrast to (1), the five-membered ring of (2) is planar, the r.m.s. deviation being only 0.009 (2) Å. PMID:21588989

  12. PubMed Central

    2011-01-01

    Events for which complete information is available are listed in chronological order. Those taking place in Italy are in bold script. Information, following the style of the present list, should be submitted to the Editorial Secretariat of Acta Otorhinolaryngologica Italica. In accordance with the Regulations of S.I.O. and Ch.C.-F. (Art. 8) Members of the Society organising Courses, Congresses or other scientific events should inform the Secretary of the Association (A.U.O.R.L., A.O.O.I.) within the deadlines set down in the respective Statutes and Regulations.

  13. Paleoseismic investigations at the Cal thrust fault, Mendoza, Argentina

    NASA Astrophysics Data System (ADS)

    Salomon, Eric; Schmidt, Silke; Hetzel, Ralf; Mingorance, Francisco

    2010-05-01

    determine the recurrence interval of these seismic events and the long-term slip rate of the fault is in progress. References Mingorance, F. (2006): Morfometría de la escarpa de falla historica identificada al norte del cerro La Cal, zona de falla La Cal, Mendoza. Revista de la Asociación Geológica Argentina, 61 (4), 620-638.

  14. Present Status of Historical Seismicity Studies in Colombia and Venezuela

    NASA Astrophysics Data System (ADS)

    Sarabia, A.; Cifuentes, H.; Altez Ortega, R.; Palme, C.; Dimate, C.

    2013-05-01

    After the publication of the SISRA (CERESIS-1985) regional project, a unified catalog of seismic parameters and intensities for South America, researchers in historical seismicity have continued advancing on different scales in the area of this study of seismic hazard. The most important initiatives carried out in this area in Colombia and Venezuela can be grouped as follows: a) Reviews of destructive earthquakes in national and international historic archives, principally by Altez and FUNVISIS in Venezuela and Espinosa, Salcedo, and Sarabia et al in Colombia, leading to the preparation of seismologic catalogues, scientific and dissemination articles, reports, books, among others. b) Organization and systematization of historic information to develop public domain data bases and information, specifically the Historic Seismologic Teleinformation System in Venezuela, carried out between 2004 and 2008 under the coordination of Christl Palme and accessible on-line: http://sismicidad.ciens.ula.ve. As well, the "Historia Sísmica de Colombia 1550-1830" (Seismic History in Colombia 1550-1830) data base, in CD-ROM, by Espinosa Baquero (2003) and the historic seismicity information system of Colombia (Servicio Geológico Colombiano-Universidad Nacional de Colombia), published on the internet in 2012: http://agata.ingeominas.gov.co:9090/SismicidadHistorica/. c) Macroseismic studies for the development of intensity attenuation equations and the quantification and revaluation of basic historic earthquake parameters using isoseismal maps (Rengifo et al., Palme et al., Salcedo et al., among others) and procedures such as Boxer and Bakun & Wentworth (Palme et al., Dimaté, among others), which have produced significant changes in the parameters of some of the large earthquakes. d) Symposiums of researchers to promote interest and development in the discipline, including Jornadas Venezolanas de Sismología Histórica (Venezuelan Congress of Historical Seismology), held

  15. Transdifferentiation of human endothelial progenitors into smooth muscle cells.

    PubMed

    Ji, HaYeun; Atchison, Leigh; Chen, Zaozao; Chakraborty, Syandan; Jung, Youngmee; Truskey, George A; Christoforou, Nicolas; Leong, Kam W

    2016-04-01

    Access to smooth muscle cells (SMC) would create opportunities for tissue engineering, drug testing, and disease modeling. Herein we report the direct conversion of human endothelial progenitor cells (EPC) to induced smooth muscle cells (iSMC) by induced expression of MYOCD. The EPC undergo a cytoskeletal rearrangement resembling that of mesenchymal cells within 3 days post initiation of MYOCD expression. By day 7, the reprogrammed cells show upregulation of smooth muscle markers ACTA2, MYH11, and TAGLN by qRT-PCR and ACTA2 and MYH11 expression by immunofluorescence. By two weeks, they resemble umbilical artery SMC in microarray gene expression analysis. The iSMC, in contrast to EPC control, show calcium transients in response to phenylephrine stimulation and a contractility an order of magnitude higher than that of EPC as determined by traction force microscopy. Tissue-engineered blood vessels constructed using iSMC show functionality with respect to flow- and drug-mediated vasodilation and vasoconstriction. PMID:26874281

  16. Hobartine: a tetracyclic indole alkaloid extracted from Aristotelia chilensis (maqui).

    PubMed

    Paz Robles, Cristian; Badilla Vidal, Natalia; Suarez, Sebastián; Baggio, Ricardo

    2014-11-01

    The natural compound hobartine {systematic name: (1R)-3-[(1S,5S)-(4,4,8-trimethylbicyclo[3.3.1]non-7-en-2-yl)methyl]-2,3-dihydro-1H-indole}, C20H26N2, (I), is an indole alkaloid isolated from Aristotelia chilensis as part of a study of secondary metabolites from Chilean flora. The colourless compound has a tetracyclic structure closely related to the strongly coloured polymorphic structures discussed in Paz et al. [Acta Cryst. (2013), C69, 1509-1512] and Watson et al. [Acta Cryst. (1989), C45, 1322-1324]. The main differences reside in the absence of a keto group in (I) compared with the previous structures, as well as an endo double bond in (I) contrasting with the exo double bond found in the previous structures. The supramolecular structure of (I) in strongly related to the twofold screw axis, around which isolated chains build up, internally linked by an N-H···N hydrogen bond which is the only significant intermolecular interaction present in the structure. PMID:25370110

  17. Lithium isotopes as a probe of weathering processes: Orinoco River

    NASA Astrophysics Data System (ADS)

    Huh, Youngsook; Chan, Lui-Heung; Edmond, John M.

    2001-12-01

    Lithium isotopes have the potential to be effective tracers of weathering processes due to their large relative mass difference and therefore fractionation. In this study an attempt is made to fill a major gap in the knowledge of Li isotope fractionation during continental weathering and of the mechanisms involved. Finally the relationship between the suspended and dissolved material is made on a basin-wide scale. The Orinoco basin provides a clear contrast in reaction-limited and transport-limited weathering regimes that has already been documented by a comprehensive study on its fluvial geochemistry (Edmond et al., Geochim. Cosmochim. Acta 60 (1996) 2949-2976; Edmond et al., Geochim. Cosmochim. Acta 59 (1995) 3301-3325). Conspicuous in our new results is the difference in δ6Li of the dissolved load between the Andean (-30 to -22‰) and Shield (-22 to -7‰) tributaries, while the δ6Li of the suspended load is similar between the two. To a first approximation, during superficial weathering in high-relief, tectonically active terrains the dissolved load is high in Li and isotopically heavy (more negative δ6Li), whereas in stable Shield regions the concentrations are low and isotopically light in proportion to the increasing degree of weathering.

  18. Aspherical-atom modeling of coordination compounds by single-crystal X-ray diffraction allows the correct metal atom to be identified.

    PubMed

    Dittrich, Birger; Wandtke, Claudia M; Meents, Alke; Pröpper, Kevin; Mondal, Kartik Chandra; Samuel, Prinson P; Amin Sk, Nurul; Singh, Amit Pratap; Roesky, Herbert W; Sidhu, Navdeep

    2015-02-01

    Single-crystal X-ray diffraction (XRD) is often considered the gold standard in analytical chemistry, as it allows element identification as well as determination of atom connectivity and the solid-state structure of completely unknown samples. Element assignment is based on the number of electrons of an atom, so that a distinction of neighboring heavier elements in the periodic table by XRD is often difficult. A computationally efficient procedure for aspherical-atom least-squares refinement of conventional diffraction data of organometallic compounds is proposed. The iterative procedure is conceptually similar to Hirshfeld-atom refinement (Acta Crystallogr. Sect. A- 2008, 64, 383-393; IUCrJ. 2014, 1,61-79), but it relies on tabulated invariom scattering factors (Acta Crystallogr. Sect. B- 2013, 69, 91-104) and the Hansen/Coppens multipole model; disordered structures can be handled as well. Five linear-coordinate 3d metal complexes, for which the wrong element is found if standard independent-atom model scattering factors are relied upon, are studied, and it is shown that only aspherical-atom scattering factors allow a reliable assignment. The influence of anomalous dispersion in identifying the correct element is investigated and discussed. PMID:25393218

  19. Internalin must be on the bacterial surface to mediate entry of Listeria monocytogenes into epithelial cells.

    PubMed

    Lebrun, M; Mengaud, J; Ohayon, H; Nato, F; Cossart, P

    1996-08-01

    Entry of Listeria monocytogenes into cultured epithelial cells requires production of internalin, a protein with features characteristic of some Gram-positive bacterial surface proteins, in particular an LPXTG motif preceding a hydrophobic sequence and a few basic residues at its C-terminal end. By immunofluorescence and immunogold labelling, we show that in wild-type L. monocytogenes, internalin is present on the cell surface and has a polarized distribution similar to that of ActA, another surface protein of L. monocytogenes involved in actin assembly. Through a genetic analysis, we establish that the C-terminal region of internalin is necessary for cell-surface association, and that although internalin is partially released in the culture medium, its location on the bacterial surface is required to promote entry. Finally, using a 'domain-swapping' strategy-replacement of the cell wall anchor of IniA by the membrane anchor of ActA- we show that the reduced ability to adhere and enter cells of strains expressing IniA-ActA correlates with a lower amount of surface-exposed internalin. Taken together, these results suggest that internalin exposed on the bacterial surface mediates direct contact between the bacterium and the host cell. PMID:8866480

  20. Crystal structure of a Pd4 carbonyl tri-phenyl-phosphane cluster [Pd4(CO)5(PPh3)4]·2C4H8O, comparing solvates.

    PubMed

    Robeyns, Koen; Willocq, Christopher; Tinant, Bernard; Devillers, Michel; Hermans, Sophie

    2016-02-01

    Attempts to synthesize Au-Pd heterometallic compounds from homonuclear palladium or gold complexes, [Pd(PtBu2)2] and [Au(PPh3)Cl] in a tetra-hydro-furan (THF) solution under a CO atmosphere resulted in a homonuclear Pd cluster, namely penta-kis-(μ-carbonyl-κ(2) C:C)tetra-kis-(tri-phenyl-phosphane-κP)tetrapalladium(5 Pd-Pd) tetra-hydro-furan disolvate, [Pd4(CO)5(C18H15P)4]·2C4H8O. The complex mol-ecule lies on a twofold rotation axis. The crystal structure is described in relation to the CH2Cl2 solvate previously determined by our group [Willocq et al. (2011 ▸). Inorg. Chim. Acta, 373, 233-242], and in particular to the desolvated structure [Feltham et al. (1985 ▸). Inorg. Chem. 24, 1503-1510]. It is assumed that the title compound transforms into the latter structure, upon gradual loss of solvent mol-ecules. In the title compound, the symmetry-unique THF solvent mol-ecule is linked to the complex mol-ecule by a weak C-H⋯O hydrogen bond. Contributions of disordered solvent molecules to the diffraction intensities, most likely associated with methanol, were removed with the SQUEEZE [Spek (2015). Acta Cryst. C71, 9-18] algorithm. PMID:26958368

  1. Crystal Structure of the Streptomyces coelicolor TetR-Like Protein ActR Alone and in Complex with Actinorhodin or the Actinorhodin Biosynthetic Precursor (S)-DNPA

    SciTech Connect

    Willems,A.; Tahlan, K.; Taguchi, T.; Zhang, K.; Lee, Z.; Ichinose, K.; Junop, M.; Nodwell, J.

    2008-01-01

    Actinorhodin, an antibiotic produced by Streptomyces coelicolor, is exported from the cell by the ActA efflux pump. actA is divergently transcribed from actR, which encodes a TetR-like transcriptional repressor. We showed previously that ActR represses transcription by binding to an operator from the actA/actR intergenic region. Importantly, actinorhodin itself or various actinorhodin biosynthetic intermediates can cause ActR to dissociate from its operator, leading to derepression. This suggests that ActR may mediate timely self-resistance to an endogenously produced antibiotic by responding to one of its biosynthetic precursors. Here, we report the structural basis for this precursor-mediated derepression with crystal structures of homodimeric ActR by itself and in complex with either actinorhodin or the actinorhodin biosynthetic intermediate (S)-DNPA [4-dihydro-9-hydroxy-1-methyl-10-oxo-3-H-naphtho-[2, 3-c]-pyran-3-(S)-acetic acid]. The ligand-binding tunnel in each ActR monomer has a striking hydrophilic/hydrophobic/hydrophilic arrangement of surface residues that accommodate either one hexacyclic actinorhodin molecule or two back-to-back tricyclic (S)-DNPA molecules. Moreover, our work also reveals the strongest structural evidence to date that TetR-mediated antibiotic resistance may have been acquired from an antibiotic-producer organism.

  2. Task effects, performance levels, features, configurations, and holistic face processing: a reply to Rossion.

    PubMed

    Riesenhuber, Maximilian; Wolff, Brian S

    2009-11-01

    A recent article in Acta Psychologica ("Picture-plane inversion leads to qualitative changes of face perception" by Rossion [Rossion, B. (2008). Picture-plane inversion leads to qualitative changes of face perception. Acta Psychologica (Amst), 128(2), 274-289]) criticized several aspects of an earlier paper of ours [Riesenhuber, M., Jarudi, I., Gilad, S., & Sinha, P. (2004). Face processing in humans is compatible with a simple shape-based model of vision. Proceedings of the Royal Society of London B (Supplements), 271, S448-S450]. We here address Rossion's criticisms and correct some misunderstandings. To frame the discussion, we first review our previously presented computational model of face recognition in cortex [Jiang, X., Rosen, E., Zeffiro, T., Vanmeter, J., Blanz, V., & Riesenhuber, M. (2006). Evaluation of a shape-based model of human face discrimination using FMRI and behavioral techniques. Neuron, 50(1), 159-172] that provides a concrete biologically plausible computational substrate for holistic coding, namely a neural representation learned for upright faces, in the spirit of the original simple-to-complex hierarchical model of vision by Hubel and Wiesel. We show that Rossion's and others' data support the model, and that there is actually a convergence of views on the mechanisms underlying face recognition, in particular regarding holistic processing. PMID:19665104

  3. Enzyme transient state kinetics in crystal and solution from the perspective of a time-resolved crystallographer

    PubMed Central

    Schmidt, Marius; Saldin, Dilano K.

    2014-01-01

    With recent technological advances at synchrotrons [Graber et al., J. Synchrotron Radiat. 18, 658–670 (2011)], it is feasible to rapidly collect time-resolved crystallographic data at multiple temperature settings [Schmidt et al., Acta Crystallogr. D 69, 2534–2542 (2013)], from which barriers of activation can be extracted. With the advent of fourth generation X-ray sources, new opportunities emerge to investigate structure and dynamics of biological macromolecules in real time [M. Schmidt, Adv. Condens. Matter Phys. 2013, 1–10] in crystals and potentially from single molecules in random orientation in solution [Poon et al., Adv. Condens. Matter Phys. 2013, 750371]. Kinetic data from time-resolved experiments on short time-scales must be interpreted in terms of chemical kinetics [Steinfeld et al., Chemical Kinetics and Dynamics, 2nd ed. (Prentience Hall, 1985)] and tied to existing time-resolved experiments on longer time-scales [Schmidt et al., Acta Crystallogr. D 69, 2534–2542 (2013); Jung et al., Nat. Chem. 5, 212–220 (2013)]. With this article, we will review and outline steps that are required to routinely determine the energetics of reactions in biomolecules in crystal and solution with newest X-ray sources. In eight sections, we aim to describe concepts and experimental details that may help to inspire new approaches to collect and interpret these data. PMID:26798774

  4. An assessment of the accuracy of isochore location techniques for H 2O-CO 2-NaCl fluids at granulite facies pressure-temperature conditions

    NASA Astrophysics Data System (ADS)

    Johnson, Eric Lee

    1992-01-01

    Synthetic H 2O-CO 2-NaCl fluid inclusions with XCO2 compositions ranging from 0.10-0.51 and relative salinities ( r-s = wtNaCl/( wt NaCl + wt H 2O )) of 6 to 23.9 wt% have been produced in spontaneously nucleated forsterite, diopside, and orthopyroxene hosts. Molar volumes of the fluids at the pressure and temperature of formation have been calculated using microthermometric data from the fluid inclusions. These P- V- T data are used to compare the accuracy of published methods of isochore location for H 2O-CO 2-NaCl fluids at elevated pressures and temperatures. The results of these analyses show that isochores calculated with the MRK equation of BOWERS and HELGESON ( Geochim. Cosmochim. Acta, vol. 47, 1247-1275, 1983) reproduce the trapping pressures and temperatures well for fluids with XCO2 ≤ 0.3 and up to 23.9 wt% NaCl. For a fluid with XCO2 = 0.49 and relative salinity of 15%, however, the agreement is poor. For these fluid compositions, the observed molar volume is larger than that predicted from the MRK equation of Bowers and Helgeson and, if not corrected, will give isochores that are too low in pressure for a given temperature. The ideal geometric mixing model of BROWN and LAMB ( Geochim. Cosmochim. Acta, vol. 53, 1209-1221, 1989) provides less satisfactory results for the fluid compositions studied.

  5. Diagnosis and epidemiological association of Listeria monocytogenes strains in two outbreaks of listerial encephalitis in small ruminants.

    PubMed Central

    Wiedmann, M; Czajka, J; Bsat, N; Bodis, M; Smith, M C; Divers, T J; Batt, C A

    1994-01-01

    Two outbreaks of epizootic listerial encephalitis, one in sheep and one in goats, were investigated through pathology, microbiology, and DNA amplification-based techniques. Efforts were made to survey the diversity of Listeria monocytogenes strains in the silage consumed by affected animals and to verify the causal relationship between silage and disease outbreak. In both outbreaks, L. monocytogenes was isolated from silage and brain tissue samples. Random amplified polymorphic DNA patterns revealed two distinct L. monocytogenes strains, one of which was identical to the sheep brain isolate, in the silage associated with the outbreak in sheep. Three brain isolates and one silage isolate, all of which had different random amplified polymorphic DNA patterns, were found in the outbreak involving goats. All isolates from both outbreaks were indistinguishable in an in vitro assay for cell-to-cell spread and growth in macrophages. All brain isolates from the goat outbreak had identical intracellular ActA patterns, which were different from the pattern for the silage isolate. While the sheep brain isolate had an ActA pattern different from that of the corresponding silage isolate, the patterns for the brain isolates from the two outbreaks were not identical. This survey demonstrates the diversity of L. monocytogenes in silage and suggests the existence of one or more selective processes by which certain strains are more prone to give rise to disease. Images PMID:8027356

  6. Ultra High-Resolution In vivo Computed Tomography Imaging of Mouse Cerebrovasculature Using a Long Circulating Blood Pool Contrast Agent

    PubMed Central

    Starosolski, Zbigniew; Villamizar, Carlos A.; Rendon, David; Paldino, Michael J.; Milewicz, Dianna M.; Ghaghada, Ketan B.; Annapragada, Ananth V.

    2015-01-01

    Abnormalities in the cerebrovascular system play a central role in many neurologic diseases. The on-going expansion of rodent models of human cerebrovascular diseases and the need to use these models to understand disease progression and treatment has amplified the need for reproducible non-invasive imaging methods for high-resolution visualization of the complete cerebral vasculature. In this study, we present methods for in vivo high-resolution (19 μm isotropic) computed tomography imaging of complete mouse brain vasculature. This technique enabled 3D visualization of large cerebrovascular networks, including the Circle of Willis. Blood vessels as small as 40 μm were clearly delineated. ACTA2 mutations in humans cause cerebrovascular defects, including abnormally straightened arteries and a moyamoya-like arteriopathy characterized by bilateral narrowing of the internal carotid artery and stenosis of many large arteries. In vivo imaging studies performed in a mouse model of Acta2 mutations demonstrated the utility of this method for studying vascular morphometric changes that are practically impossible to identify using current histological methods. Specifically, the technique demonstrated changes in the width of the Circle of Willis, straightening of cerebral arteries and arterial stenoses. We believe the use of imaging methods described here will contribute substantially to the study of rodent cerebrovasculature. PMID:25985192

  7. Symmetry breaking in actin gels - Implications for cellular motility

    NASA Astrophysics Data System (ADS)

    John, Karin; Peyla, Philippe; Misbah, Chaouqi

    2007-03-01

    The physical origin of cell motility is not fully understood. Recently minimal model systems have shown, that polymerizing actin itself can produce a motile force, without the help of motor proteins. Pathogens like Shigella or Listeria use actin to propel themselves forward in their host cell. The same process can be mimicked with polystyrene beads covered with the activating protein ActA, which reside in a solution containing actin monomers. ActA induces the growth of an actin gel at the bead surface. Initially the gel grows symmetrically around the bead until a critical size is reached. Subsequently one observes a symmetry breaking and the gel starts to grow asymmetrically around the bead developing a tail of actin at one side. This symmetry breaking is accompanied by a directed movement of the bead, with the actin tail trailing behind the bead. Force generation relies on the combination of two properties: growth and elasticity of the actin gel. We study this phenomenon theoretically within the framework of a linear elasticity theory and linear flux-force relationships for the evolution of an elastic gel around a hard sphere. Conditions for a parity symmetry breaking are identified analytically and illustrated numerically with the help of a phasefield model.

  8. Crystal structure of a Pd4 carbonyl tri­phenyl­phosphane cluster [Pd4(CO)5(PPh3)4]·2C4H8O, comparing solvates

    PubMed Central

    Robeyns, Koen; Willocq, Christopher; Tinant, Bernard; Devillers, Michel; Hermans, Sophie

    2016-01-01

    Attempts to synthesize Au–Pd heterometallic compounds from homonuclear palladium or gold complexes, [Pd(PtBu2)2] and [Au(PPh3)Cl] in a tetra­hydro­furan (THF) solution under a CO atmosphere resulted in a homonuclear Pd cluster, namely penta­kis­(μ-carbonyl-κ2 C:C)tetra­kis­(tri­phenyl­phosphane-κP)tetrapalladium(5 Pd—Pd) tetra­hydro­furan disolvate, [Pd4(CO)5(C18H15P)4]·2C4H8O. The complex mol­ecule lies on a twofold rotation axis. The crystal structure is described in relation to the CH2Cl2 solvate previously determined by our group [Willocq et al. (2011 ▸). Inorg. Chim. Acta, 373, 233–242], and in particular to the desolvated structure [Feltham et al. (1985 ▸). Inorg. Chem. 24, 1503–1510]. It is assumed that the title compound transforms into the latter structure, upon gradual loss of solvent mol­ecules. In the title compound, the symmetry-unique THF solvent mol­ecule is linked to the complex mol­ecule by a weak C—H⋯O hydrogen bond. Contributions of disordered solvent molecules to the diffraction intensities, most likely associated with methanol, were removed with the SQUEEZE [Spek (2015). Acta Cryst. C71, 9–18] algorithm. PMID:26958368

  9. Monte Carlo simulation of electrothermal atomization on a desktop personal computer

    NASA Astrophysics Data System (ADS)

    Histen, Timothy E.; Güell, Oscar A.; Chavez, Iris A.; Holcombea, James A.

    1996-07-01

    Monte Carlo simulations have been applied to electrothermal atomization (ETA) using a tubular atomizer (e.g. graphite furnace) because of the complexity in the geometry, heating, molecular interactions, etc. The intense computational time needed to accurately model ETA often limited its effective implementation to the use of supercomputers. However, with the advent of more powerful desktop processors, this is no longer the case. A C-based program has been developed and can be used under Windows TM or DOS. With this program, basic parameters such as furnace dimensions, sample placement, furnace heating and kinetic parameters such as activation energies for desorption and adsorption can be varied to show the absorbance profile dependence on these parameters. Even data such as time-dependent spatial distribution of analyte inside the furnace can be collected. The DOS version also permits input of external temperaturetime data to permit comparison of simulated profiles with experimentally obtained absorbance data. The run-time versions are provided along with the source code. This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hardcopy text is accompanied by a diskette with a program (PC format), data files and text files.

  10. Syntenic assignment of human chromosome 1 homologous loci in the bovine.

    PubMed

    Threadgill, D S; Threadgill, D W; Moll, Y D; Weiss, J A; Zhang, N; Davey, H W; Wildeman, A G; Womack, J E

    1994-08-01

    Three mouse chromosomes (MMU 1, 3, and 4) carry homologs of human chromosome 1 (HSA 1) genes. A similar situation is found in the bovine, where five bovine chromosomes (BTA 2, 3, 5, 16, and unassigned syntenic group U25) contain homologs of HSA 1 loci. To evaluate further the syntenic relationship of HSA 1 homologs in cattle, 10 loci have been physically mapped through segregation analysis in bovine-rodent hybrid somatic cells. These loci, chosen for their location on HSA 1, are antithrombin 3 (AT3), renin (REN), complement component receptor 2 (CR2), phosphofructokinase muscle type (PFKM), Gardner-Rasheed feline sarcoma viral (v-fgr) oncogene homolog (FGR), alpha fucosidase (FUCA1), G-protein beta 1 subunit (GNB1), alpha 1A amylase, (AMY1), the neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS), and alpha skeletal actin (ACTA1). AT3, REN, CR2, and GNB1 mapped to BTA 16, PFKM to BTA 5, AMY1A and NRAS to BTA 3, FGR and FUCA1 to BTA 2, and ACTA1 to BTA 28. PMID:8001974

  11. The Kalman filter approach to inductively coupled plasma atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Van Veen, E. H.; Bosch, S.; De Loos-Vollebregt, M. T. C.

    1994-07-01

    This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hardcopy text, comprising the main article and two appendices, is accompanied by a disk containing the compiled program, a reference manual and data files. The work deals with data handling in inductively coupled plasma atomic emission spectrometry (ICP-AES). With this technique, the analyte signal is superimposed on a background signal. When separating the signals by manual or automated three-point background correction, there are many instances in which the data reduction fails. Based on scans recorded in a fast-scanning mode and on a library of pure-component scans, the Kaiman filter approach models the emission in the spectral window (about 100 pm) of the analyte and mathematically solves the problem of background correction. By using a criterion-based algorithm to correct for optical instability, the uncertainty in the determination of the interferent line signal is eliminated. Therefore, the present filter implementation yields more accurate and precise results, especially in the case of line overlap. The Kalman filter Approach to Atomic Spectrometry (KAAS) software automatically processes Perkin-Elmer Plasma 1000/2000 text files, but can also handle ASCII data files. Practical and comprehensive examples are given to evoke the "Kalman filter feeling" in the crucial step of creating the emission model.

  12. Listeria monocytogenes Exploits Normal Host Cell Processes to Spread from Cell to Cell✪

    PubMed Central

    Robbins, Jennifer R.; Barth, Angela I.; Marquis, Hélène; de Hostos, Eugenio L.; Nelson, W. James; Theriot, Julie A.

    1999-01-01

    The bacterial pathogen, Listeria monocytogenes, grows in the cytoplasm of host cells and spreads intercellularly using a form of actin-based motility mediated by the bacterial protein ActA. Tightly adherent monolayers of MDCK cells that constitutively express GFP-actin were infected with L. monocytogenes, and intercellular spread of bacteria was observed by video microscopy. The probability of formation of membrane-bound protrusions containing bacteria decreased with host cell monolayer age and the establishment of extensive cell-cell contacts. After their extension into a recipient cell, intercellular membrane-bound protrusions underwent a period of bacterium-dependent fitful movement, followed by their collapse into a vacuole and rapid vacuolar lysis. Actin filaments in protrusions exhibited decreased turnover rates compared with bacterially associated cytoplasmic actin comet tails. Recovery of motility in the recipient cell required 1–2 bacterial generations. This delay may be explained by acid-dependent cleavage of ActA by the bacterial metalloprotease, Mpl. Importantly, we have observed that low levels of endocytosis of neighboring MDCK cell surface fragments occurs in the absence of bacteria, implying that intercellular spread of bacteria may exploit an endogenous process of paracytophagy. PMID:10491395

  13. Mutation-Specific Effects on Thin Filament Length in Thin Filament Myopathy

    PubMed Central

    de Winter, Josine M.; Joureau, Barbara; Lee, Eun-Jeong; Kiss, Balázs; Yuen, Michaela; Gupta, Vandana A.; Pappas, Christopher T.; Gregorio, Carol C.; Stienen, Ger J. M.; Edvardson, Simon; Wallgren-Pettersson, Carina; Lehtokari, Vilma-Lotta; Pelin, Katarina; Malfatti, Edoardo; Romero, Norma B.; van Engelen, Baziel G.; Voermans, Nicol C.; Donkervoort, Sandra; Bönnemann, C. G.; Clarke, Nigel F.; Beggs, Alan H.; Granzier, Henk; Ottenheijm, Coen A. C.

    2016-01-01

    Objective Thin filament myopathies are among the most common nondystrophic congenital muscular disorders, and are caused by mutations in genes encoding proteins that are associated with the skeletal muscle thin filament. Mechanisms underlying muscle weakness are poorly understood, but might involve the length of the thin filament, an important determinant of force generation. Methods We investigated the sarcomere length-dependence of force, a functional assay that provides insights into the contractile strength of muscle fibers as well as the length of the thin filaments, in muscle fibers from 51 patients with thin filament myopathy caused by mutations in NEB, ACTA1, TPM2, TPM3, TNNT1, KBTBD13, KLHL40, and KLHL41. Results Lower force generation was observed in muscle fibers from patients of all genotypes. In a subset of patients who harbor mutations in NEB and ACTA1, the lower force was associated with downward shifted force–sarcomere length relations, indicative of shorter thin filaments. Confocal microscopy confirmed shorter thin filaments in muscle fibers of these patients. A conditional Neb knockout mouse model, which recapitulates thin filament myopathy, revealed a compensatory mechanism; the lower force generation that was associated with shorter thin filaments was compensated for by increasing the number of sarcomeres in series. This allowed muscle fibers to operate at a shorter sarcomere length and maintain optimal thin–thick filament overlap. Interpretation These findings might provide a novel direction for the development of therapeutic strategies for thin filament myopathy patients with shortened thin filament lengths. PMID:27074222

  14. Determination of barium, chromium, cadmium, manganese, lead and zinc in atmospheric particulate matter by inductively coupled plasma atomic emission spectrometry (ICP-AES)

    NASA Astrophysics Data System (ADS)

    Boevski, I. V.; Daskalova, N.; Havezov, I.

    2000-11-01

    The present paper has shown that the Q concept, as proposed by P.W.J.M. Boumans, J.J.A.M. Vrakking, Spectrochim. Acta Part B 43 (1988) 69, can be used as a basic methodology in the determination of Ba, Cr, Cd, Mn, Pb and Zn in pairs of atmospheric particles by inductively coupled plasma atomic emission spectrometry (ICP-AES). The data base of Q values for line interference [ QIj(λ a)] and Q values for wing background interference [ QWJ(Δλ a)] were obtained in our former work [N. Daskalova, Iv. Boevski, Spectral interferences in the determination of trace elements in environmental materials by inductively coupled plasma atomic emission spectrometry, Spectrochim. Acta Part B 54 (1999) 1099-1122]. The samples of atmospheric particles were collected by the Bergerhoff method. The ICP-AES determination was performed after sample digestion with aqua regia. Q values were used for the calculation of both the total interfering signal under the analysis lines and the true detection limits, depending on the matrix constituents in the different samples. Comparative data for the concentration of analytes were obtained by flame atomic absorption spectrometry (FAAS) and direct current arc atomic emission spectrographic method (dc arc-AES).

  15. Parameter identification of chaos system based on unknown parameter observer

    NASA Astrophysics Data System (ADS)

    Wang, Shaoming; Luo, Haigeng; Yue, Chaoyuan; Liao, Xiaoxin

    2008-04-01

    Parameter identification of chaos system based on unknown parameter observer is discussed generally. Based on the work of Guan et al. [X.P. Guan, H.P. Peng, L.X. Li, et al., Acta Phys. Sinica 50 (2001) 26], the design of unknown parameter observer is improved. The application of the improved approach is extended greatly. The works in some literatures [X.P. Guan, H.P. Peng, L.X. Li, et al., Acta Phys. Sinica 50 (2001) 26; J.H. Lü, S.C. Zhang, Phys. Lett. A 286 (2001) 148; X.Q. Wu, J.A. Lu, Chaos Solitons Fractals 18 (2003) 721; J. Liu, S.H. Chen, J. Xie, Chaos Solitons Fractals 19 (2004) 533] are only the special cases of our Corollaries 1 and 2. Some observers for Lü system and a new chaos system are designed to test our improved method, and simulations results demonstrate the effectiveness and feasibility of the improved approach.

  16. Influence of static magnetic fields combined with human insulin-like growth factor 1 on human satellite cell cultures.

    PubMed

    Birk, Richard; Sommer, J Ulrich; Haas, Dominik; Faber, Anne; Aderhold, Christoph; Schultz, Johannes D; Hoermann, Karl; Stern-Straeter, Jens

    2014-01-01

    Tissue engineering represents a promising research field, targeting the creation of new functional muscle tissue in vitro. The aim of the present study was to show the influence of static magnetic fields (SMF) and insulin-like growth factor-1 (IGF1), as enhancing stimuli on human satellite cell cultures, which are preferred sources of stem cells in engineering skeletal muscle tissue. To detect effects on myogenic maturation and proliferation, AlamarBlue® proliferation, assay and semi-quantitative reverse transcription-polymerase chain reaction of following markers was performed: desmin (DES), myogenic factor-5 (MYF5), myogenic differentiation antigen-1 (MYOD1), myogenin (MYOG), myosin heavy chain (MYH) and α1 actin (ACTA1). As a distinct marker of differentiation, immunohistochemical staining and fusion index determination was performed on satellite cell cultures stimulated with IGF1 and IGF1-plus-SMF with an intensity of 80 mT. Proliferation was increased by additional SMF application to IGF1-stimulated cell cultures on the first day of myogenesis. Relative gene expression of measured markers was increased by IGF1 application in the first days of myogenesis except for ACTA1. Additional SMF application enhanced this effect. Nevertheless we were unable to demonstrate the formation of contractile muscle tissue. Immunhistochemical staining verified muscle origin and all markers were displayed. PMID:25189891

  17. Um Projeto de Intervenção nos Espaços de Exposições do Planetário do Parque do Ibirapuera

    NASA Astrophysics Data System (ADS)

    Elias, D. S.; Amaral, L. H.; de Araújo, C. F., Jr.; Matsuura, O. T.; Voelzke, M. R.

    2005-08-01

    Cada vez mais a humanidade, em sua imensa maioria, está alheia às próprias conquistas. A insatisfação com esta realidade tem levado muitos pesquisadores, instituições, empresas e governos a procurar formas alternativas de acompanhar e transmitir todo este acervo científico cultural à sociedade, buscando a melhoria da qualidade da divulgação científica e contribuindo para o processo de cultura e alfabetização científica. Não há tempo nem espaço nos limitados planos curriculares do ensino médio e mesmo nos programas de ensino que propiciem a cultura científica e o acompanhamento do vertiginoso progresso científico e tecnológico atual. Neste sentido, a educação formal escolar precisa ser complementada ou acrescida de uma educação informal, extra-escolar, que possa oferecer à sociedade o que a escola não pode oferecer. A interação do público com museus, feiras de ciências, planetários, exposições científicas e/ou culturais é de grande importância para a aquisição e difusão de conhecimentos relacionados ao mundo científico. Reconhecidamente como um modelo de alfabetização científica esses ambientes promovem uma interação social capaz de propiciar de forma efetiva uma melhor relação ensino-aprendizagem com o público. Partindo desta realidade a Universidade Cruzeiro do Sul e a Escola Municipal de Astronomia (EMA) vêm desenvolvendo um projeto de intervenção no espaço em torno do Planetário do Parque do Ibirapuera com o objetivo de se implantar um ambiente de aprendizagem motivador e desafiador que promova a popularização de conteúdos relacionados à astronomia, astrofísica e cosmologia. Busca-se, também, a aproximação e interação do público com exposições que estão sendo implementadas no planetário. Considerando que se trata de um projeto de mestrado em fase inicial o objetivo do presente trabalho é apresentar a concepção básica e os critérios que estão sendo utilizados do ponto de vista pedag

  18. Science with the ASTRI mini-array for the Cherenkov Telescope Array: blazars and fundamental physics

    NASA Astrophysics Data System (ADS)

    Bonnoli, Giacomo; Tavecchio, Fabrizio; Giuliani, Andrea; Bigongiari, Ciro; Di Pierro, Federico; Stamerra, Antonio; Pareschi, Giovanni; Vercellone, Stefano; ASTRI Collaboration; CTA Consortium

    2016-05-01

    ASTRI (“Astronomia a Specchi con Tecnologia Replicante Italiana”) is a flagship project of the Italian Ministry of Research (MIUR), devoted to the realization, operation and scientific validation of an end-to-end prototype for the Small Size Telescope (SST) envisaged to become part of the Cherenkov Telescope Array (CTA). The ASTRI SST-2M telescope prototype is characterized by a dual mirror, Schwarzschild-Couder optical design and a compact camera based on silicon photo-multipliers. It will be sensitive to multi-TeV very high energy (VHE) gamma rays up to 100 TeV, with a PSF ~ 6’ and a wide (9.6°) unaberrated optical field of view. Right after validation of the design in single-dish observations at the Serra La Nave site (Sicily, Italy) during 2015, the ASTRI collaboration will be able to start deployment, at the final CTA southern site, of the ASTRI mini-array, proposed to constitute the very first CTA precursor. Counting 9 ASTRI SST-2M telescopes, the ASTRI mini-array will overtake current IACT systems in differential sensitivity above 5 TeV, thus allowing unprecedented observations of known and predicted bright TeV emitters in this band, including some extragalactic sources such as extreme high-peaked BL Lacs with hard spectra. We exploited the ASTRI scientific simulator ASTRIsim in order to understand the feasibility of observations tackling blazar and cosmic ray physics, including discrimination of hadronic and leptonic scenarios for the VHE emission from BL Lac relativistic jets and indirect measurements of the intergalactic magnetic field and of the extragalactic background light. We selected favorable targets, outlining observation modes, exposure times, multi-wavelength coverage needed and the results expected. Moreover, the perspectives for observation of effects due to the existence of axion-like particles or to Lorentz invariance violations have been investigated.

  19. Tycho Brahe - Instrumentenbauer und Meister der Beobachtungstechnik

    NASA Astrophysics Data System (ADS)

    Wolfschmidt, Gudrun

    Vor der Erfindung des Fernrohrs war der dänische Astronom Tycho Brahe (1546 - 1601) der bedeutendste beobachtende Astronom. Von seinem Observatorium Uraniborg auf der - damals dänischen - Insel Hven ist heute noch der Grundriß erkennbar, von Stjerneborg sind die Fundamente erhalten, die Kuppeln in den 1950er Jahren ergänzt. In der Astronomie-Ausstellung im Deutschen Museum gibt es ein Modell der Sternwarte Uraniborg und der zugehörigen Instrumente (Maßstab 1:10); das größere Modell wurde dem Technischen Museum in Malmö geschenkt. Die Instrumente, die er in den Observatorien Uraniborg und Stjerneborg benutzte, sind nicht erhalten. Aber es gibt gute Beschreibungen der Instrumente (Halbkreis, Quadranten, Sextanten, Armillarsphären, Triquetrum, Himmelsglobus) in seinem Buch Astronomiae instauratae mechanica (Wandsbek 1598). Eine Nachbildung des großen hölzernen Quadranten kann man im Runden Turm in Kopenhagen sehen. Zwei Sextanten, hergestellt für Tycho um 1600 von Jost Bürgi und Erasmus Habermel, gibt es noch im Nationalmuseum für Technik in Prag. Ähnlichkeiten von Tychos Instrumenten mit Groß-Instrumenten aus dem islamischen Kulturkreis sind auffällig. Tycho Brahes Meßgeräte markieren einen großen Fortschritt in der Entwicklung astronomischer Instrumente und Meßtechniken und bilden die Grundlage für den weiteren Fortschritt der Positionsastronomie und der damit verbundenen Tabellenwerke. Die Nachwirkungen sind bis ins 17. und 18. Jahrhundert nachweisbar.

  20. From Fragments to a museum display: restoration of a Gautier meridian circle

    NASA Astrophysics Data System (ADS)

    Granato, Marcus

    2009-07-01

    The Museu de Astronomia e Ciências Afins (MAST), which opened to the public in 1985, is a research institute of the Brazilian Ministry of Science and Technology. One of its main activities is to preserve its collections, especially the most important one, its collection of scientific instruments, which grants MAST its identity as a museum of science and technology. Among the 2,000 objects in the collection there is a Gautier meridian circle that has a 190-mm diameter objective lens and a focal distance of 2,400 mm, with its axis aligned east-west. It should be noted that this instrument was at great risk of being lost to the collection, as it had been left dismantled since the 1960s, and the top part of the dome that sheltered it had been demolished in the 1980s, leaving just a vestibule and the base of the dome, which was in danger of completely collapsing. The intervention philosophy applied was not to put the instrument back in working order, but to allow it to be viewed and understood by the public within a coherent display space. As for the dome, a shelter was built for the instrument using a metal cover of a similar volume and appearance to the original, but with a different function, i.e. it is no longer designed to permit astronomical investigations, but rather to protect the exhibition space and merge harmoniously with the rest of the listed architectural complex. This paper presents information about the history of this meridian circle and its restoration, as well as about the Imperial Observatório do Rio de Janeiro/Observatório Nacional where this instrument was originally used.

  1. Inauguração do Telescópio SOAR

    NASA Astrophysics Data System (ADS)

    Steiner, João

    2004-04-01

    A comunidade astronômica brasileira de há muito almeja ter a sua disposição um instrumento científico com o qual possa fazer pesquisa de vanguarda e manter a competitividade científica a nível internacional. Hoje este sonho se torna uma realidade. O Brasil tem tido uma política de pesquisa e de pós-graduação bem sucedida. Estamos formando 7000 doutores por ano e produzimos 1,5% da ciência mundial. Nosso desafio, hoje, é associar a esta capacidade de gerar conhecimento também a capacidade de usar o conhecimento em beneficio da sociedade. A Astronomia não é exceção. Temos 7 programas de pós-graduação em nível de doutorado e 11 em nível de mestrado. O telescópio SOAR será o principal instrumento que sustentará estes programas nas próximas décadas. A inauguração do telescópio SOAR simboliza de forma concreta e decidida o apoio do MCT, do CNPq e da FAPESP para o financiamento à pesquisa básica em nosso país. O Laboratório Nacional de Astrofísica, criado a cerca de 20 anos pelo CNPq, a par do Laboratório Nacional de Luz Sincrotron, são até hoje, os únicos laboratórios nacionais do Brasil e ambos voltados basicamente ao avanço do conhecimento. Os vinte anos de existência do LNA foram decisivos para a estruturação da comunidade astronômica no Brasil e para a construção das parcerias como o SOAR.

  2. The first published chart of the Andromeda Nebula, 1667

    NASA Astrophysics Data System (ADS)

    Gingerich, Owen

    2014-06-01

    The Parisian astronomer Ismaél Bullialdus (1605-1694) is known for his planetary tables (Astronomia philolaica, 1645) based on a geometrical approximation to the Keplerian ellipse, and for his long correspondence with the Danzig astronomer Johannes Hevelius and with Christiaan Huygens. Bullialdus became interested in the nascent study of variable stars, and in 1667 published a small pamphlet with two contributions, one on Mira Ceti and the other on the nebula in Andromeda. He found a manuscript portraying the nebula with the date 1428, and because Tycho Brahe never mentioned a nebula in Andromeda, Bullialdus conjectured that this object was a variable that had disappeared in the intervening era. “We conclude this since this conglomeration was observed neither by Hipparchus nor anyone else in antiquity, nor in the previous age by Tycho, nor in the age of our forefathers like Bayer.” His publication included a handsome engraving of the image of Andromeda and the position of the nebula, its first printed chart. I recently acquired a copy of this rare pamphlet, Ad astronomos monita duo, and realized that the image matched a manuscript now in the Gotha Research Library, a 15th-century Latin version based on the work of the tenth-century Islamic astronomer, al-Sufi. The manuscript does not carry the name of al-Sufi, and hence Bullialdus had no real clue about its origin or its date of composition. Paul Kunitzsch (The Arabs and the Stars, 1989, Article XI, “The Astronomer Abu ’l-Husayn al-Sufi”) has identified a group of eight “Latin al-Sufi” manuscripts from this period, scattered in European libraries, but only the one now in Gotha is an exact match to Bullialdus’ engraving. The al-Sufi manuscript was given to the Gotha Library in 1798 by Duke Ernst II of Saxonia-Gotha-Altenburg, who must have acquired it from France sometime in the 18th century.

  3. The Stellar Population of NGC 5634: A Globular Cluster in the Sagittarius dSph Stream?

    NASA Astrophysics Data System (ADS)

    Bellazzini, Michele; Ferraro, Francesco R.; Ibata, Rodrigo

    2002-08-01

    We present the first (V,V-I) color-magnitude diagram (CMD) for the poorly studied globular cluster NGC 5634. The CMD shows a steep red giant branch (RGB) and a predominantly blue horizontal branch (HB): both these characteristics suggest a low metal content for this cluster. From the position of the RGB in the CMD we estimate [Fe/H]=-1.94+/-0.10 and E(B-V)=0.06+/-0.01. The CMD presented here reaches V~=23, allowing us to obtain the first measure of the main-sequence turnoff (TO) VTO=21.22+/-0.15 for this cluster. By combining this figure with the apparent luminosity of the zero-age HB (ZAHB), VZAHB=17.90+/-0.10 we obtain ΔVHBTO=3.32+/-0.16, a value which is fully compatible with that derived for the bulk of Galactic globulars. We also derive a true distance modulus of (m-M)0=17.17+/-0.12, corresponding to a distance of ~27.2 kpc. Most interestingly, the cluster is shown to have position and radial velocity fully compatible with the orbit of the Sagittarius dwarf spheroidal galaxy (dSph). The similarity between the stellar populations of the cluster and the Sagittarius globular Ter 8 and the metal-poor population of the Sagittarius dSph also suggests that NGC 5634 was a former member of this disrupting galaxy, torn off by the Galactic tidal field and now lost in the Sagittarius stream. Based on observations made with the Italian Telescopio Nazionale Galileo, operated on the island of La Palma by the Centro Galileo Galilei of the Consorzio Nazionale per l'Astronomia e l'Astrofisica at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.

  4. Brazilian Eratosthenes Project

    NASA Astrophysics Data System (ADS)

    Langhi, R.; Vilaça, J.

    2014-10-01

    The objective of Brazilian Eratosthenes Project is the development and application of teaching training actions according the ``docent autonomy" concept to basic Astronomy Education. Argentina coordinates the project in South America, but Brazil works in this project since 2010 with the theme ``Projeto Eratóstenes Brasil" in the homepage: http://sites.google.com/site/projetoerato. Two schools measure a sticks shadow and communicate their results. After, they calculate an average radius of Earth. The stick (gnomon) should stay in vertical position in the leveled ground. Since 2010, the project received hundreds of Brazilian schools with different experiments that were constructed with autonomy, because our site doesn't show some itinerary pre-ready to elaborate the experiments. To collect data for our research, we will use interviews via Skype with the teachers. These data are useful to researches about Science Education area and the Teaching Formation. Teaching professional practice could change and we see modifications in the teachers work, what depends of their realities and context. This project intents to respect the docent autonomy. This autonomy to responsible modifications during continued formation is called ``activist formative model" according Langhi & Nardi (Educação em Astronomia: repensando a formação de professores. São Paulo: Escrituras Editora, 2012). This project discusses about researches in Astronomy Education - still extreme rare in Brazil, when we compare with other areas in Science Education. We believe that actions like this could motivate the students to learn more Astronomy. Furthermore, this national action can be a rich source of data to investigations about teaching formation and scientific divulgation.

  5. Analysis of the New Sodium Emission Feature Discovered in Io's Wake

    NASA Astrophysics Data System (ADS)

    Lovering, Jessica; Schneider, N. M.; Grava, C.; Barbieri, C.

    2009-09-01

    Recent observations have revealed a new high-velocity sodium emission feature near Io's wake, in addition to the two well-known emission features of Io's neutral cloud. Using the SARG spectrograph on the 3.6-m Telescopio Nazionale Galileo in the Canary Islands, we observed three distinct spectral features lying parallel to Io's orbit. While the "banana cloud” of slow sodium and the fast sodium "jet” or "stream” are well understood, the Jupiter-ward orientation and high velocity (>10 km/s) of this new feature make it quite unexpected. Unlike the slow sodium of the banana cloud, the velocity of this new feature suggests a source process due to electrodynamic interactions, similar to Io's jet or stream. However, the Jupiter-ward direction of this new feature suggests it does not have the same source mechanism as the jet, which ejects opposite Jupiter. In our pre- and post-eclipse observations we found that this new feature disappears after eclipse, suggesting that the source mechanism is inhibited by atmospheric collapse or a change in photoionization. We will present characterization of this new feature including extent, velocity distribution, and source rate. Modeling the velocity distribution and comparing with observed velocity distributions allow us to pinpoint the source mechanism. We will also discuss the most likely source processes based on the observations. This work has been supported by NSF's Planetary Astronomy Program, INAF/TNG, Dipartimento di Astronomia and CISAS, Università di Padova, through a contract by the Italian Space Agency ASI.

  6. Reverse and concurrent engineering applied of a high resolution equipment Berkut for 1-meter class telescopes

    NASA Astrophysics Data System (ADS)

    López, R.; Granados, R.; Farah, A.

    2014-07-01

    Several factors make observational astronomy difficult for astronomers; one of them is the atmosphere. The light that a star emits is refracted when it goes through the earth's atmosphere; the result of this is that the image of a punctual star is not what the physics would lead us to expect. At the Instituto de Astronomia of the Universidad Nacional Autonoma de México (IA-UNAM) an instrument has been developed called "Berkut", which uses a high resolution technique to improve these effects and obtain interesting and valuable scientific studies. In this paper we present the mechanical reengineering and acceptance test of Berkut. This instrument was design for taking images of high resolution. Essentially, it is composed by a set basic optics which is aligned and in focus with a 1- meter class telescope. It has its own electronic components for controlling remotely a filter wheel; that allows the exchange of the filters according to the requirements of the observer, a couple of objectives mounted in a translation stage, and a CCD camera for acquiring several images per second that are used in the speckle interferometry technique. A project like Berkut needs to be multidisciplinary; astronomy, engineering, optics, mechanics, electronics, and image processing are some of the areas of knowledge used. Berkut will be used in the telescope of the Observatorio Astronomico Nacional in Tonantzintla, located in the state of Puebla, Mexico, but it can be used in any telescope 1 meter class. It is pretended to build another Berkuts for being used simultaneously in different telescopes, so it is important to keep the costs as low as possible. With this instrument we pretend to confirm the Hipparcos catalogue of binary stars besides finding exoplanets.

  7. Heritage and Observatories in Brazil at the Turn of the Twentieth Century: an Overview

    NASA Astrophysics Data System (ADS)

    Granato, Marcus

    The first systematic asronomical observations in the southern hemisphere were in Pernambuco, northeastern Brazil, in the short period of Dutch rule in the region (1637-1644). Later, in the late nineteenth and early twentieth centuries, there were three observatories on Brazilian soil: Imperial Observatório do Rio de Janeiro, Observatório da Escola Politecnica, both in Rio de Janeiro and Observatório Central, in the southern city of Porto Alegre. The first was created by Imperial decree by D. Pedro I, on 15 October 1827, while the second, linked to Universidade do Brasil, was established on 5 July 1881. The third was planned in 1889, but only inaugurated on 24 January 1908 as part of the Escola de Engenharia. All three institutions exist to this day, and their scientific instruments of historical value are included in cultural heritage preservation projects. The largest collection of this kind of objects is at Museu de Astronomia e Ciéncias Afins (MAST), most of whose 2000 artefacts come from the Imperial Observatory (today the National Observatory). Many of them were produced in Germany by manufacturers such as Gustav Heyde, Carl Zeiss, Askania-Werke, Carl Bamberg and Max Kohl. The buildings of the Observatório Central (1921) and Observatório Nacional (1921) are listed by federal and state heritage protection agencies, particularly because they were purpose built for astronomical research and have architectural features typical of the late nineteenth and early twentieth centuries that have not been altered over the years.

  8. Practical Astronomical Activities during Daytime. (Spanish Title: Actividades Astronómicas Prácticas Diurnas.) Atividades Astronômicas Práticas Diurnas

    NASA Astrophysics Data System (ADS)

    Jackson, Eric

    2009-12-01

    relacionadas al mal tiempo. El problema de no tener suficientes actividades prácticas, la sensación de poseer conocimientos inadecuados, la necesidad de disponer de equipamiento astronómico y experiencia suelen ser demasiado intimidantes para que los profesores introduzcan la materia en sus clases. Si la Astronomía iba a ser introducida, entonces era preciso encontrar una forma de resolver estas dificultades. Nuestro grupo, trabajando con maestros y alumnos dentro de un marco constructivista, encontró que los principios de la Astronomía pueden ser descubiertos durante el día, en cuanto los alumnos están en la escuela. Trabajando de forma cooperativa los alumnos midieron y registraron observaciones de sus propias sombras causadas por los movimientos de la estrella más próxima, el Sol, y nuestro planeta Tierra. Debido a que los alumnos se involucraran tan personalmente en las actividades, estuvieron mucho más interesados en los resultados del estudio. La Astronomía pasó a ser un desafío para el maestro y sus alumnos cuando aplicaron sus experiencias diurnas a la observación nocturna desde sus casas, reportada después en clase. Estas atividades astronômicas diurnas surgiram de uma investigação feita na Nova Zelândia por um grupo de professores e astrônomos a respeito dos problemas do ensino da Astronomia. Este trabalho mostrou que a Astronomia é geralmente considerada uma disciplina difícil de ensinar, tradicionalmente baseada em livros, filmes e modelos. Os mais afortunados podem ter feito alguma visita a um observatório ou planetário, e os mais avançados podem talvez ter tentado uma sessão de observação noturna, as quais sofrem às vezes de dificuldades relacionadas ao tempo. O problema de não dispor de suficientes atividades práticas, a sensação de possuir conhecimentos inadequados, a necessidade de dispor de equipamento astronômico e experiência tem sido, em geral, demasiado intimidante para que os professores introduzam a matéria nas suas

  9. A Proposed Activity for a Meaningful Learning about the Moon Phases. (Breton Title: Uma Proposta de Atividade Para a Aprendizagem Significativa sobre as Fases da Lua.) Una Actividad Propuesta Para EL Aprendizaje Significativo Acerca de Las Fases de la Luna

    NASA Astrophysics Data System (ADS)

    Martins, Bruno Andrade; Langhi, Rodolfo

    2012-12-01

    This paper presents one of the concepts of Astronomy and its consequent failure in teaching this topic in high school, even when the official documents point out the necessity of Astronomy teaching at this school level. Among the spontaneous conceptions in Astronomy that high school students carry with them, even after the end of the school, we emphasized in this research the Moon phases. The development of different strategies in relation to traditional methods, aimed to teaching-learning process on this topic was considered in this study. These strategies were devised based on the reference frame of the Meaningful Learning, as elaborated by Ausubel. The proposals presented here include the active participation of students in experimental activities and other didactic activities, for their continuous evaluation during the process. These activities finished with a Comics elaboration about the Moon phases. Therefore, the objective of this paper is to present a proposal for differentiated teaching activity about Moon phases supported by the theoretical principles of Meaningful Learning at Physics classes. Este texto foca um dos conteúdos de Astronomia e a consequente falha no ensino deste tema no ensino médio, apesar de os documentos oficiais apresentarem a necessidade de se trabalhar a Astronomia neste nível de ensino. Dentre as concepções alternativas em Astronomia que os alunos do ensino médio carregam consigo, mesmo após o término dos estudos, destacamos, nesta pesquisa, o fenômeno das fases da Lua. O desenvolvimento de estratégias diferenciadas em relação ao ensino tradicional, visando o processo de ensino-aprendizagem sobre este tema, foi contemplado neste trabalho como um dos resultados obtidos sob a luz dos referenciais da aprendizagem significativa, fundamentados em Ausubel. Segundo a proposta aqui apresentada, a participação ativa dos alunos na execução de uma atividade experimental e outras atividades didáticas, que visam sua cont

  10. Accretion and differentiation of carbon in the early Earth.

    PubMed

    Tingle, T N

    1998-05-15

    The abundance of C in carbonaceous and ordinary chondrites decreases exponentially with increasing shock pressure as inferred from the petrologic shock classification of Scott et al. [Scott, E.R.D., Keil, K., Stoffler, D., 1992. Shock metamorphism of carbonaceous chondrites. Geochim. Cosmochim. Acta 56, 4281-4293] and Stoffler et al. [Stoffler, D., Keil, K., Scott, E.R.D., 1991. Shock metamorphism of ordinary chondrites. Geochim. Cosmochim. Acta 55, 3845-3867]. This confirms the experimental results of Tyburczy et al. [Tyburczy, J.A., Frisch, B., Ahrens, T.J., 1986. Shock-induced volatile loss from a carbonaceous chondrite: implications for planetary accretion. Earth Planet. Sci. Lett. 80, 201-207] on shock-induced devolatization of the Murchison meteorite showing that carbonaceous chondrites appear to be completely devolatilized at impact velocities greater than 2 km s-1. Both of these results suggest that C incorporation would have been most efficient in the early stages of accretion, and that the primordial C content of the Earth was between 10(24) and 10(25) g C (1-10% efficiency of incorporation). This estimate agrees well with the value of 3-7 x 10(24) g C based on the atmospheric abundance of 36Ar and the chondritic C/36Ar (Marty and Jambon, 1987). Several observations suggest that C likely was incorporated into the Earth's core during accretion. (1) Graphite and carbides are commonly present in iron meteorites, and those iron meteorites with Widmanstatten patterns reflecting the slowest cooling rates (mostly Group I and IIIb) contain the highest C abundances. The C abundance-cooling rate correlation is consistent with dissolution of C into Fe-Ni liquids that segregated to form the cores of the iron meteorite parent bodies. (2) The carbon isotopic composition of graphite in iron meteorites exhibits a uniform value of -5% [Deines, P., Wickman, F.E. 1973. The isotopic composition of 'graphitic' carbon from iron meteorites and some remarks on the troilitic

  11. Hydrogeologic uncertainties and policy implications: The Water Consumer Protection Act of Tucson, Arizona, USA

    NASA Astrophysics Data System (ADS)

    Wilson, L. G.; Matlock, W. G.; Jacobs, K. L.

    confusion entre "infiltration" et "recharge". C'est ainsi que la loi laisse entendre que l'infiltration à partir des lits de rivières le long du champ captant central favorise la recharge de cette zone. En réalité, les différences de perméabilité entre les alluvions du lit et les dépôts sous-jacents remplissant le bassin peuvent provoquer un écoulement sous-jacent. En outre, même si une recharge par l'eau de la rivière Colorado se produit dans cette zone, la nappe sera progressivement salifiée. Les restrictions imposées par la loi quant à l'utilisation de l'eau de la station centrale d'Arizona affectent les quatre outils réglementaires du Code des eaux souterraines de l'Arizona de 1980, en ce qu'ils concernent la zone de gestion active de Tucson: (a) l'augmentation de l'approvisionnement (b) les conditions requises pour les prélèvements d'eau souterraine et les autorisations; (c) les conditions requises pour le plan de gestion, en particulier la pérennité du concessionnaire et les résultats en matière de qualité de l'eau et (d) la condition que tous les nouveaux districts aient recours à des ressources en eau renouvelables à la place de l'eau souterraine. Les demandes concernant la mise en oeuvre de la loi ont conduit jusqu'à l'arrêt des activités normales des instances politiques. Resumen El Acta de Protección de los Usuarios de Agua de Tucson, Arizona (EE.UU.) de 1995 (el Acta) se aprobó a raíz de las quejas de los usuarios de agua de Tucson que recibían agua tratada por el Proyecto de Arizona Central (CAP). Las consecuencias del Acta demuestran las incertidumbres y dificultades que se producen cuando se le pide al público que vote sobre temas muy técnicos. Los requerimientos de recarga del Acta desprecian incertidumbres hidrogeológicas al confundir entre "infiltración" y "recarga". Así, el Acta dice que la infiltración en los canales de los arroyos a lo largo del Campo de Producción Central aumentará la recarga a dicho campo. De

  12. Automated CO2 extraction from air for clumped isotope analysis in the atmo- and biosphere

    NASA Astrophysics Data System (ADS)

    Hofmann, Magdalena; Ziegler, Martin; Pons, Thijs; Lourens, Lucas; Röckmann, Thomas

    2015-04-01

    The conventional stable isotope ratios 13C/12C and 18O/16O in atmospheric CO2 are a powerful tool for unraveling the global carbon cycle. In recent years, it has been suggested that the abundance of the very rare isotopologue 13C18O16O on m/z 47 might be a promising tracer to complement conventional stable isotope analysis of atmospheric CO2 [Affek and Eiler, 2006; Affek et al. 2007; Eiler and Schauble, 2004; Yeung et al., 2009]. Here we present an automated analytical system that is designed for clumped isotope analysis of atmo- and biospheric CO2. The carbon dioxide gas is quantitatively extracted from about 1.5L of air (ATP). The automated stainless steel extraction and purification line consists of three main components: (i) a drying unit (a magnesium perchlorate unit and a cryogenic water trap), (ii) two CO2 traps cooled with liquid nitrogen [Werner et al., 2001] and (iii) a GC column packed with Porapak Q that can be cooled with liquid nitrogen to -30°C during purification and heated up to 230°C in-between two extraction runs. After CO2 extraction and purification, the CO2 is automatically transferred to the mass spectrometer. Mass spectrometric analysis of the 13C18O16O abundance is carried out in dual inlet mode on a MAT 253 mass spectrometer. Each analysis generally consists of 80 change-over-cycles. Three additional Faraday cups were added to the mass spectrometer for simultaneous analysis of the mass-to-charge ratios 44, 45, 46, 47, 48 and 49. The reproducibility for δ13C, δ18O and Δ47 for repeated CO2 extractions from air is in the range of 0.11o (SD), 0.18o (SD) and 0.02 (SD)o respectively. This automated CO2 extraction and purification system will be used to analyse the clumped isotopic signature in atmospheric CO2 (tall tower, Cabauw, Netherlands) and to study the clumped isotopic fractionation during photosynthesis (leaf chamber experiments) and soil respiration. References Affek, H. P., Xu, X. & Eiler, J. M., Geochim. Cosmochim. Acta 71, 5033

  13. An examination of the regulatory mechanism of Pxdn mutation-induced eye disorders using microarray analysis.

    PubMed

    Yang, Yang; Xing, Yiqiao; Liang, Chaoqun; Hu, Liya; Xu, Fei; Mei, Qi

    2016-06-01

    The present study aimed to identify biomarkers for peroxidasin (Pxdn) mutation-induced eye disorders and study the underlying mechanisms involved in this process. The microarray dataset GSE49704 was used, which encompasses 4 mouse samples from embryos with Pxdn mutation and 4 samples from normal tissues. After data preprocessing, the differentially expressed genes (DEGs) between Pxdn mutation and normal tissues were identified using the t-test in the limma package, followed by functional enrichment analysis. The protein-protein interaction (PPI) network was constructed based on the STRING database, and the transcriptional regulatory (TR) network was established using the GeneCodis database. Subsequently, the overlapping DEGs with high degrees in two networks were identified, as well as the sub-network extracted from the TR network. In total, 121 (75 upregulated and 46 downregulated) DEGs were identified, and these DEGs play important roles in biological processes (BPs), including neuron development and differentiation. A PPI network containing 25 nodes such as actin, alpha 1, skeletal muscle (Acta1) and troponin C type 2 (fast) (Tnnc2), and a TR network including 120 nodes were built. By comparing the two networks, seven crucial genes which overlapped were identified, including cyclin‑dependent kinase inhibitor 1B (Cdkn1b), Acta1 and troponin T type 3 (Tnnt3). In the sub-network, Cdkn1b was predicted as the target of miRNAs such as mmu-miR-24 and transcription factors (TFs) including forkhead box O4 (FOXO4) and activating enhancer binding protein 4 (AP4). Thus, we suggest that seven crucial genes, including Cdkn1b, Acta1 and Tnnt3, play important roles in the progression of eye disorders such as glaucoma. We suggest that Cdkn1b exert its effects via the inhibition of proliferation and is mediated by mmu-miR-24 and targeted by the TFs FOXO4 and AP4. PMID:27121343

  14. Predictive Framework and Experimental Tests of the Kinetic Isotope Effect at Redox-Active Interfaces

    NASA Astrophysics Data System (ADS)

    Kavner, A.; John, S.; Black, J. R.

    2013-12-01

    Electrochemical reactions provide a compelling framework to study kinetic isotope effects because redox-related processes are important for a wide variety of geological and environmental processes. In the laboratory, electrochemical reaction rates can be electronically controlled and measured in the laboratory using a potentiostat. This enables variation of redox reactions rates independent of changes in chemistry and, and the resulting isotope compositions of reactants and products can be separated and analyzed. In the past years, a series of experimental studies have demonstrated a large, light, and tunable kinetic isotope effect during electrodeposition of metal Fe, Zn, Li, Cu, and Mo from a variety of solutions (e.g. Black et al., 2009, 2010, 2011). A theoretical framework based on Marcus kinetic theory predicts a voltage-dependent kinetic isotope effect (Kavner et al., 2005, 2008), however while this framework was able to predict the tunable nature of the effect, it was not able to simultaneously predict absolute reaction rates and relative isotope rates. Here we present a more complete development of a statistical mechanical framework for simple interfacial redox reactions, which includes isotopic behavior. The framework is able to predict a kinetic isotope effect as a function of temperature and reaction rate, starting with three input parameters: a single reorganization energy which describes the overall kinetics of the electron transfer reaction, and the equilibrium reduced partition function ratios for heavy and light isotopes in the product and reactant phases. We show the framework, elucidate some of the predictions, and show direct comparisons against isotope fractionation data obtained during laboratory and natural environment redox processes. A. Kavner, A. Shahar, F. Bonet, J. Simon and E. Young (2005) Geochim. Cosmochim. Acta, 69(12), 2971-2979. A. Kavner, S. G. John, S. Sass, and E. A. Boyle (2008), Geochim. Cosmochim. Acta, vol 72, pp. 1731

  15. Mechanism of amorphous silica particles precipitation: simulation approach compared to experimental results

    NASA Astrophysics Data System (ADS)

    Noguera, Claudine; Fritz, Bertrand; Clement, Alain

    2015-04-01

    Despite its importance in numerous industrial and natural processes, many unsolved questions remain regarding the mechanism of silica precipitation in aqueous solutions: order of the reaction, role of silica oligomers, existence of an induction time and characteristics of the particle population. Beyond empirical approaches used in the past, we demonstrate that the classical nucleation theory associated to a size dependent growth law, as embedded in the NANOKIN code (1-3), allows a quantitative description of precipitation occurring under largely different experimental conditions : preexisting initial supersaturation in a large domain of temperature (5-150°C) and chemical composition (4), supersaturation reached by neutralization of a high pH silica solution (5) or by fast cooling (6). In that way, the mechanism of silica precipitation can be unraveled. We are able to discard the hypothesis of an induction time as an explanation for the plateaus observed in the saturation curves in these experiments. We challenge the role of oligomer incorporation at the growth stage to account for the observed rate laws and we stress the difference between the order of the growth law and the order of the total reaction rate. We also demonstrate that the characteristics of the particle population are strongly dependent on the way supersaturation is reached (7). Such a microscopic approach thus proves to be well suited to elucidate the mechanism of nanoparticle formation in natural and industrial contexts, involving silica, but also other mineral phases produced as nanoparticles (8). (1) Noguera C., Fritz B., Clément A. and Barronet A., J. Cryst. Growth, 2006, 297, 180. (2) Noguera C., Fritz B., Clément A. and Barronet A., J. Cryst. Growth, 2006, 297, 187. (3) Fritz B., Clément A., Amal Y. and Noguera C., Geochim. Cosmochim. Acta, 2009, 73, 1340. (4) Rothbaum, H.P. and Rohde A.G., J. Colloid Interf. Sci., 1979,71, 533. (5) Tobler D.J., Shaw S. and Benning L.G., Geochim

  16. 40Ar/39Ar dating of the Honghuaqiao Formation in SE China

    NASA Astrophysics Data System (ADS)

    Chang, S.; Zhang, H.; Hemming, S. R.; Mesko, G. T.; Fang, Y.

    2010-12-01

    The Jehol Biota, defined as the characteristic Eosestheria-Ephemeropsis-Lycoptera assemblage (Grabau, 1923, Bulletin of the Geological Survey of China), is widely distributed in eastern and central Asia (Li et al., 1982, Acta Geologica Sinica; Chen, 1988, Acta Palaeontologica Sinica). Abundant and varied fossils of the terrestrial Jehol Biota, including plants, insects, dinosaurs, birds, mammals, and freshwater invertebrates, have been discovered from the Dabeigou, the Yixian and the Jiufotang Formations (or their correlative strata) in northeast China from the Liaoning and Hebei Provinces and Inner Mongolia (Chen and Jin, 1999, Acta Palaeontologica Sinica). In addition, strata that may be correlative with the classic Jehol fossil-bearing formations have been identified extensively in central and eastern China, the Korean Peninsula, Mongolia, and Siberia. In the past three decades mollusk, conchostracan, ostracod, insect, fish, and plant fossils from localities in southeastern China, interpreted as related to the Jehol biota of the northeast, have been found (Mateer and Chen, 1986, Cretaceous Research; Li, 2003, Chinese Science Bulletin; Chen, Li and Batten, 2007, Geological Journal). However, a detailed correlation between the classic Jehol outcrops and the more recently found localities to the South and West has yet to emerge. Volcanic rocks from the Honghuaqiao fossil-bearing Formation in Tuzhou City of eastern Anhui Province, southeastern China provide an excellent opportunity to rectify this situation. Preliminary results of a pilot study suggest that the Honghuaqiao Formation is equivalent to the Longwanshan Formation of Anhui Province, southeastern China and the Yixian Formation, northeastern China (Chang et al., 2009, AGU abstract). Initial 40Ar/39Ar results indicate that conchostracans from the upper Honghuaqiao Formation are approximately 130 Ma. Our ongoing work aims to establish a high-resolution chronostratigraphy for Tuzhou City in Anhui Province

  17. Biogeochemistry of Sulfur Intermediates in Marine Sediments - Insights from Laboratory and Field Studies

    NASA Astrophysics Data System (ADS)

    Ferdelman, T. G.; Milucka, J.; Kuypers, M. M. M.; Berg, J.; Buckner, C.; Graf, J.; Holmkvist, L.; Jørgensen, B. B.; Kamyshny, A.; Piepgras, L.

    2014-12-01

    The sulfur cycle in marine sediments exerts a major control on the redox state of the ocean and atmosphere. The overall driver in the sulfur cycle is the microbial mediated sulfate reduction to sulfide (SR), In near-surface sediments, only a small fraction of the sulfide produced becomes permanently buried in the reduced form as pyrite (FeS2) Paradoxically, the deep, reduced, sulfidic zone of marine sediments is often characterized by the presence of zero-valent sulfur compounds, e.g. elemental sulfur and polysulfides [1,2,3]. The presence of oxidized iron and manganese has been suggested as the source of oxidizing power for the formation of elemental S and polysulfides in these deep, anoxic and sulfidic sediment environments, which often lie at or below the sulfate-methane transition [1,3]. The findings of Milucka et al. [4] suggest that anaerobic oxidation of methane coupled to sulfate reduction (AOM) may provide another source of zerovalent sulfur to such environments. AOM is thought to be mediated by a consortium of methanotrophic archaea (ANME) and sulfate-reducing Deltaproteobacteria. Milucka et al. [4] show that zero-valent sulfur compounds (S0) are formed during AOM-coupled SR and conclude that the S0 is a product of a novel pathway for sulfate reduction performed by the ANME. Thus, AOM may not be an obligately syntrophic process. Furthermore, the produced S0, in the form of hydrodisulfide, can serve as a substrate for disproportionation by the Deltaproteobacteria associated with the ANME, and that this disproptionation proceeds under sulfidic conditions. These observations may have significant implications for role of sulfur intermediates in our understanding of the biogeochemical carbon and sulfur cycle in modern and past environments. [1] Holmkvist et al. (2011) Geochim. Cosmochim. Acta 75, 3581-3599. [2] Lichtschlag et al. (2013) Geochim. Cosmochim. Acta 105, 130-145. [3] Holmkvist et al. (2014) Geochim. Cosmochim. Acta, accepted. [4] Milucka et al

  18. An update on 11B,10B fractionation in the fundamental reaction: 10B(OH)3 + 11B(OH)4- = 11B(OH)3 + 10B(OH)4-

    NASA Astrophysics Data System (ADS)

    Klochko, K.; Tossell, J. A.

    2007-12-01

    It has recently been demonstrated experimentally by Byrne, et al. (2006) and Klochko, et al. (2006) that the equilibrium constant for the isotopic exchange reaction: 10B(OH)3 + 11B(OH)4- = 11B(OH)3 + 10B(OH)4- (1) has a value around 1.027 for seawater at 25°C, for total B concentrations from 0.01 to 0.05 molal. These experimental studies involved essentially the accurate determination of the small pKa difference between the 11B and 10B isotopomers of boric acid. This new equilibrium constant value is significantly higher than the traditional value of 1.0194 from Kakihana, et al. (1977). This result has been obscured in recent controversies (Honisch, et al., 2007). The new value agrees well with the ab initio quantum cluster calculated values of Liu and Tossell (2005) and with the ab initio MD harmonic values of Rustad and Bylaska (2007). We will present additional calculations supporting and extending the study of Liu and Tossell (2005) and will discuss the general unsuitability of methods such as Sanchez-Valle, et al. (2005) which employ experimental spectral data. We have also established that polyborate formation in solutions as concentrated as 0.50 molal total B has little effect on the equilibrium constant. A mechanism is also presented for the interaction of B(OH)3 and B(OH)4- with HCO3- species occurring on the calcite surface. References: Byrne, et al. Deep-Sea Research I (2006) 53, 684-688. Honisch, et al. Geochim. Cosmochim. Acta (2007) 71, 1636-1641. Kakihana, et al. Bull. Chem. Soc. Jpn. (1977) 50, 158-163. Klochko, et al. Earth Planet. Sci. Lett. (2006) 248, 276-285. Liu and Tossell Geochim. Cosmochim. Acta (2005) 69, 3995-4006. Rustad and Bylaska J. Am. Chem. Soc. (2007) 129, 2222-2223. Sanchez-Valle, et al. Geochim. Cosmochim. Acta (2005) 69, 4301-4313.

  19. Major Cation, Carbon System and Trace Element Chemistry in Pore Waters from a Depth Transect of Cores on the Iberian Margin: Implications for Paleoproxies.

    NASA Astrophysics Data System (ADS)

    Greaves, M.; Elderfield, H.; Hodell, D. A.; Skinner, L. C.; Sevilgen, D.; Grauel, A. L.; de la Fuente, M.; Misra, S.

    2014-12-01

    A significant body of work exists on the chemistry of pore waters from DSDP and ODP drilling cores (e.g. Gieskes 1975; Sayles 1981) showing large gradients in sea salt cations and anions interpreted in terms of diagenetic reactions such as the formation of Mg-rich clays and dolomite formation (Higgins and Schrag, 2010). Another class of diagenetic reactions involves the breakdown of organic matter and trace element behaviour (Froelich et al., 1979). The translation of chemical gradients into fluxes requires estimates of pore water chemistry across the sea water - sediment surface boundary. Additionally, the use of the chemistry of benthic foraminiferal calcite for seawater paleochemistry requires estimation of the chemistry of pore waters which may differ from that of bottom seawater because of diagenetic reactions. In this work we have collected multi core samples from 10 core sites on cruise RRS James Cook JC089 on the southwest Iberian continental margin. Pore waters were extracted from the core surface and at 1 cm depth intervals down core (typically to ~40 cm depth) using Rhizon samplers and analysed for Alkalinity, DIC, ∂13C and Na, K, Mg, Ca, Li, Mn, Fe, Ba, B, Sr by atomic emission spectrophotometry as well as O2 penetration and pH by microelectrodes. This has allowed us to inspect chemical behavior at the bottom water - sediment interface. Some examples of results are a large gradient in ∂13C of DIC, the similarity of zero O2 penetration followed by an increase in Mn concentration and then decrease to zero, the similarity of Li to Mn and, in contrast to much DSDP/ODP work, Ca2+ and Mg2+both decrease with depth in pore waters near the sediment surface. References: Gieskes J.M. Annu. Rev. Earth Planet. Sci. 3, 433 (1975). Sayles F. L. Geochim. Cosmochim. Acta45, 1061 (1981). Higgins J.A. and D.P. Schrag. Geochim. Cosmochim. Acta.74, 5039 (2010). Froelich, P.N., et al., Geochim. Cosmochim. Acta. 43, 1075 (1979).

  20. Epigenetic and phenotypic changes result from a continuous pre and post natal dietary exposure to phytoestrogens in an experimental population of mice

    PubMed Central

    Guerrero-Bosagna, Carlos M; Sabat, Pablo; Valdovinos, Fernanda S; Valladares, Luis E; Clark, Susan J

    2008-01-01

    Background Developmental effects of exposure to endocrine disruptors can influence adult characters in mammals, but could also have evolutionary consequences. The aim of this study was to simulate an environmental exposure of an experimental population of mice to high amounts of nutritional phytoestrogens and to evaluate parameters of relevance for evolutionary change in the offspring. The effect of a continuous pre- and post-natal exposure to high levels of dietary isoflavones was evaluated on sexual maturity, morphometric parameters and DNA methylation status in mice. Adult mice male/female couples were fed ad libitum either with control diet (standard laboratory chow) or ISF diet (control diet plus a soy isoflavone extract at 2% (w/w) that contained the phytoestrogens genistein and daidzein). In the offspring we measured: i) the onset of vaginal opening (sexual maturation) in females, ii) weight and size in all pups at 7, 14, 21 and 42 days post-natal (dpn) and iii) DNA methylation patterns in skeletal α-actin (Acta1), estrogen receptor-α and c-fos in adults (42 dpn). Results Vaginal opening was advanced in female pups in the ISF group, from 31.6 ± 0.75 dpn to 25.7 ± 0.48. No differences in size or weight at ages 7, 14 or 21 dpn were detected between experimental groups. Nevertheless, at age 42 dpn reduced size and weight were observed in ISF pups, in addition to suppression of normal gender differences in weight seen in the control group (males heavier that females). Also, natural differences seen in DNA methylation at Acta1 promoter in the offspring originated in the control group were suppressed in the ISF group. Acta1 is known to be developmentally regulated and related to morphomotric features. Conclusion This study demonstrates in mammals that individuals from a population subjected to a high consumption of isoflavones can show alterations in characters that may be of importance from an evolutionary perspective, such as epigenetic and morphometric

  1. Detection of multiple virulence-associated genes in Listeria monocytogenes isolated from bovine mastitis cases.

    PubMed

    Rawool, D B; Malik, S V S; Shakuntala, I; Sahare, A M; Barbuddhe, S B

    2007-01-25

    Clinical samples (n=725) were collected from bovines (n=243) which were positive for mastitis using the California mastitis test (CMT) and somatic cell count (SCC). The clinical samples comprising blood (n=239), milk (n=243), and faecal swabs (n=243) were examined for the presence of pathogenic Listeria spp. Isolation of the pathogen was done using selective enrichment in University of Vermont Medium and plating onto Dominguez-Rodriguez isolation agar. Confirmation of the isolates was based on biochemical tests and Christie, Atkins, Munch-Petersen (CAMP) test followed by pathogenicity testing. Pathogenicity of the isolates was tested by phosphatidylinositol-specific phospholipase C (PI-PLC) assay as well as in vivo tests namely, chick embryo and mice inoculation tests. The isolates were subjected to PCR assay for five virulence-associated genes, plcA, prfA, hlyA, actA and iap. Listeria spp. were isolated from 12 (1.66%) samples. Of these 4 (0.55%) and 1 (0.14%) were confirmed as Listeria monocytogenes and Listeria ivanovii, respectively. L. monocytogenes and L. ivanovii were recovered from milk samples (2) and faecal (3) of mastitic cattle (3) and buffaloes (2). L. monocytogenes recovered from the milk of mastitic cattle and L. ivanovii from the faecal swab of buffalo turned out to be pathogenic. However, the remaining three hemolytic isolates exhibiting positive CAMP test turned out to be negative in PI-PLC assay, chick embryo and mice inoculation. L. monocytogenes and L. ivanovii isolates characterized as pathogenic by PI-PLC assay and in vivo pathogenicity tests were found to possess all the five virulence-associated genes and three genes, plcA, prfA and actA respectively. The remaining three hemolytic but non-pathogenic L. monocytogenes isolates were negative for plcA by PCR. It seems that the plcA gene and its expression (in the PI-PLC assay) have an important role as virulence determinants in pathogenic Listeria spp. In conclusion, the PI-PLC assay and

  2. Isolation, identification, and characterization of Listeria spp. from various animal origin foods

    PubMed Central

    Nayak, Deepti N.; Savalia, C. V.; Kalyani, I. H.; Kumar, Rajeev; Kshirsagar, D. P.

    2015-01-01

    Aim: The present study was undertaken with the prime objective of isolating and identifying Listeria spp. from various foods of animal origin sold at retail market outlets in the city of Navsari, Gujarat. Materials and Methods: Total 200 samples comprising of milk, milk products, meat, and fish (50 each) collected aseptically from local market which were subjected first to pre-enrichment in half strength Fraser broth followed by enrichment in full strength Fraser broth and subsequent plating on PALCAM agar. The growth with the typical colony characteristics were further identified up to species level on the basis of their morphological and biochemical characteristics. Cultures identified as Listeria monocytogenes were further subjected to in vitro pathogenicity tests and detection of different virulence-associated genes viz. actA, hlyA, and iap using polymerase chain reaction. Results: Of the total 200 food samples of animal origin; 18 (9%) were found positive for Listeria spp. which were identified as Listeria seeligeri (6, 33.3%), Listeria innocua (5, 27.7%), Listeria welshimeri (4, 22.2%), and L. monocytogenes (3, 16.6%). The highest prevalence was observed in milk samples (8). Species wise, 6 isolates of L. seeligeri which included two each from cow milk, buffalo milk, and meat samples; 5 L. innocua isolates included four recovered from fish and one from meat sample; 4 L. welshimeri comprised of two isolates from ice cream and one each from buffalo milk and meat sample; and 3 isolates of L. monocytogenes recovered from milk (1 cow and 2 buffalo milk). All 3 L. monocytogenes isolates screened for the presence of virulence genes viz. actA, hlyA, and iap using the specific primers revealed the presence of all the genes suggesting the possibility of danger of foodborne listeriosis among raw milk consumers. Conclusion: Listeria spp. was isolated from 9% (18/200) of the animal origin food samples viz.; milk, milk products, meat, and fish with the highest prevalence

  3. Si transfers during Archean weathering processes traced by silicon isotopes and Ge/Si ratios

    NASA Astrophysics Data System (ADS)

    Delvigne, Camille; Opfergelt, Sophie; Hofmann, Axel; Cardinal, Damien; André, Luc

    2015-04-01

    Weathering conditions in the Mesoarchean are poorly constrained. Recent advances in analytical capabilities have added Si isotopes and Ge/Si ratios to the repertoire of tracers used in the study of soil formation processes: neoformation of secondary clay minerals is associated with large Si isotope and Ge/Si fractionation in response to desilication processes and the weathering degree [1, 2, 3, 4]. Here we combine Si isotopes and Ge/Si ratios of a Mesoarchean paleosol (~2.95 Ga) and of nearly coeval but younger shales as proxies of weathering processes and Si mass transfer at the early Earth's surface. The paleosol is developed on andesite and shows a well defined mineralogical and chemical differentiation. In a first step, similar to modern soils, neoformation of secondary clay minerals in the paleosol was associated with fractionation of Si isotopes and Ge/Si ratios in response to chemical weathering degree and soil desilication. In a second step, the loss of Fe(II)-rich minerals, likely Fe-rich smectites, due to low pO2 conditions produced additional control on Si and Ge mobilities. Opposite fractionation behaviors are observed: products of desilication acted as 28Si and Ge sink while the leaching of Fe(II)-rich minerals released 28Si and Ge to soil solutions. Furthermore, the shales deposited immediately after the paleosol display δ30Si and Ge/Si compositions which may be explained as mixtures of the recognized Archean paleosols components. Their recording within the sedimentary pile suggests that the observed weathering-induced desilication might have been widely effective during the Mesoarchean as well as Fe(II)-rich minerals leaching in a lesser extent and pointing out these processes as determinant in the Si transfers from continents to hydrosphere. [1] Kurtz et al., (2002) Geochim. Cosmochim. Acta 66, 1525-1537 [2] Ziegler et al., (2005) Geochim. Cosmochim. Acta 69, 4597-4610. [3] Opfergelt et al., (2010) Geochim. Cosmochim. Acta 74, 225-240. [4

  4. Molybdenum Cycling in Upwelling Sediments: An Example from Namibian Margin Sediments

    NASA Astrophysics Data System (ADS)

    Arnold, G. L.; Goldhammer, T.; Formolo, M.; Brunner, B.; Ferdelman, T.

    2008-12-01

    (1973), Geochim. Cosmochim. Acta 87, 1415. (2)McManus et al. (2006), Geochim. Cosmochim. Acta 70, 4643. (3)Erickson and Helz (2000) Geochim. Cosmochim. Acta 64, 1149.

  5. Crystal structure of bis­(2-amino-5-chloro­pyridinium) tetra­chlorido­cobaltate(II)

    PubMed Central

    Mghandef, Marwa; Boughzala, Habib

    2015-01-01

    The title salt, (C5H6ClN2)2[CoCl4], was synthesized by slow evaporation of an aqueous solution at room temperature. The asymmetric unit consists of two essentially planar (C5H6ClN2)+ cations [maximum deviations = 0.010 (3) and 0.014 (3) Å] that are nearly perpendicular to each other [dihedral angle = 84.12 (7)°]. They are bonded through N—H⋯Cl hydrogen bonds to distorted [CoCl4]2− tetra­hedra, leading to the formation of undulating layers parallel to (100). The structure is isotypic with the Zn analogue [Kefi et. al (2011). Acta Cryst. E67, m355–m356.] PMID:25995878

  6. Redetermination of cytosinium hydrogen maleate–cytosine (1/1) from the original data

    PubMed Central

    Fábry, Jan

    2016-01-01

    The title salt, C4H6N3O+·C4H3O4 −·C4H5N3O, has been redetermined from the data published by Benali-Cherif, Falek & Direm [Acta Cryst. (2009), E65, o3058–o3059]. The improvement of the present redetermination consists in the discovery of the splitting of one of the H atoms into two disordered positions, the occupancies of which are equal to 0.55 (2) and 0.45 (2). These H atoms are involved in an N⋯N hydrogen bond and are shifted towards its centre. The disorder of these H atoms is in agreement with a similar environment of the two independent, but chemically equivalent, cytosinium/cytosine mol­ecules. PMID:27375877

  7. 3α-Hy­droxy­tirucalla-8,24-dien-21-oic acid

    PubMed Central

    Yousuf, S.; Kamdem, R. S. T.; Ngadjui, B. T.; Wafo, P.; Fun, Hoong-Kun

    2011-01-01

    The title compound, C30H48O3, a triterpene isolated from the resin of canarium schweinfurthiiand, is an isomer of the previously reported triterpene 3α-hy­droxy­tirucalla-7,24-dien-21-oic acid [Mora et al. (2001 ▶). Acta Cryst. C57, 638–640], which crystallizes in the same trigonal space group. The title mol­ecule consists of four fused rings having chair, half-chair, half-chair and envelope conformations for rings A, B, C and D, respectively (steroid labelling). An intra­molecular C—H⋯O hydrogen bond generates an S(7) ring. In the crystal, mol­ecules are linked by O—H⋯O and C—H⋯O inter­actions, forming (001) sheets. PMID:21754206

  8. Tetra-amminepalladium(II) dichloride ammonia tetra-solvate.

    PubMed

    Grassl, Tobias; Korber, Nikolaus

    2014-07-01

    The title compound, [Pd(NH3)4]Cl2·4NH3, was crystallized in liquid ammonia from the salt Pd(en)Cl2 (en is ethylenediamine) and is isotypic with [Pt(NH3)4]Cl2·4NH3 [Grassl & Korber (2014 ▶). Acta Cryst. E70, i31]. The Pd(2+) cation is coordinated by four ammonia mol-ecules, exhibiting a square-planar geometry. The chloride anions are surrounded by nine ammonia mol-ecules. These are either bound in the palladium complex or solvent mol-ecules. The packing of the ammonia solvent mol-ecules enables the formation of an extended network of N-H⋯N and N-H⋯Cl inter-actions with nearly ideal hydrogen-bonding geometry. PMID:25161505

  9. Tetra-ammineplatinum(II) dichloride ammonia tetra-solvate.

    PubMed

    Grassl, Tobias; Korber, Nikolaus

    2014-07-01

    The title compound, [Pt(NH3)4]Cl2·4NH3, was crystallized in liquid ammonia from the salt PtCl2. The platinum cation is coordinated by four ammonia mol-ecules, forming a square-planar complex. The chloride anions are surrounded by nine ammonia mol-ecules, either bound within the platinum complex or solvent mol-ecules. The solvent ammonia mol-ecules are packed in such a way that an extended network of N-H⋯N and N-H⋯Cl hydrogen bonds is formed. The structure is isotypic with [Pd(NH3)4]Cl2·4NH3 [Grassl & Korber (2014). Acta Cryst. E70, i32]. PMID:25161504

  10. Editorial

    NASA Astrophysics Data System (ADS)

    Gill, Eberhard

    2016-06-01

    This Special Section of Acta Astronautica is a collection of selected peer reviewed papers presented at the eighth International Workshop on Satellite Constellations and Formation Flying (IWSCFF). The event was, as its predecessors, organized by the Astrodynamics Committee of the International Astronautical Federation (IAF) with the objective to bring together specialists in the area of astrodynamics and space mission analysis and design and to promote discussions on lessons from past missions, to present recent results, and to address challenges for future space missions. The Workshop was held at the Faculty of Aerospace Engineering of the Delft University of Technology from June 8-10, 2015. The Workshop was coordinated by its Chairs Eberhard Gill (The Netherlands) and Alfred Ng (Canada) with support from the recently established TU Delft Space Institute, an extended International Program Committee, a Local Organizing Committee and a variety of industrial and institutional sponsors.

  11. Glycomic and sialoproteomic data of gastric carcinoma cells overexpressing ST3GAL4

    PubMed Central

    Mereiter, Stefan; Magalhães, Ana; Adamczyk, Barbara; Jin, Chunsheng; Almeida, Andreia; Drici, Lylia; Ibáñez-Vea, Maria; Larsen, Martin R.; Kolarich, Daniel; Karlsson, Niclas G.; Reis, Celso A.

    2016-01-01

    Gastric carcinoma MKN45 cells stably transfected with the full-length ST3GAL4 gene were characterised by glycomic and sialoproteomic analysis. Complementary strategies were applied to assess the glycomic alterations induced by ST3GAL4 overexpression. The N- and O-glycome data were generated in two parallel structural analyzes, based on PGC-ESI-MS/MS. Data on glycan structure identification and relative abundance in ST3GAL4 overexpressing cells and respective mock control are presented. The sialoproteomic analysis based on titanium-dioxide enrichment of sialopeptides with subsequent LC-MS/MS identification was performed. This analysis identified 47 proteins with significantly increased sialylation. The data in this article is associated with the research article published in Biochim Biophys Acta “Glycomic analysis of gastric carcinoma cells discloses glycans as modulators of RON receptor tyrosine kinase activation in cancer” [1]. PMID:27077082

  12. Acanthamoeba polyphaga mimivirus NDK: preliminary crystallographic analysis of the first viral nucleoside diphosphate kinase

    PubMed Central

    Jeudy, Sandra; Coutard, Bruno; Lebrun, Régine; Abergel, Chantal

    2005-01-01

    The complete sequence of the largest known double-stranded DNA virus, Acanthamoeba polyphaga mimivirus, has recently been determined [Raoult et al. (2004 ▶), Science, 306, 1344–1350] and revealed numerous genes not expected to be found in a virus. A comprehensive structural and functional study of these gene products was initiated [Abergel et al. (2005 ▶), Acta Cryst. F61, 212–215] both to better understand their role in the virus physiology and to obtain some clues to the origin of DNA viruses. Here, the preliminary crystallographic analysis of the viral nucleoside diphosphate kinase protein is reported. The crystal belongs to the cubic space group P213, with unit-cell parameter 99.425 Å. The self-rotation function confirms that there are two monomers per asymmetric unit related by a twofold non-crystallographic axis and that the unit cell thus contains four biological entities. PMID:16511098

  13. Redetermination of cytosinium hydrogen maleate-cytosine (1/1) from the original data.

    PubMed

    Fábry, Jan

    2016-04-01

    The title salt, C4H6N3O(+)·C4H3O4 (-)·C4H5N3O, has been redetermined from the data published by Benali-Cherif, Falek & Direm [Acta Cryst. (2009), E65, o3058-o3059]. The improvement of the present redetermination consists in the discovery of the splitting of one of the H atoms into two disordered positions, the occupancies of which are equal to 0.55 (2) and 0.45 (2). These H atoms are involved in an N⋯N hydrogen bond and are shifted towards its centre. The disorder of these H atoms is in agreement with a similar environment of the two independent, but chemically equivalent, cytosinium/cytosine mol-ecules. PMID:27375877

  14. The investigation of chemical structure of coal macerals via transmitted-light FT-IR microscopy by X. Sun

    USGS Publications Warehouse

    Hower, J.C.; Suarez-Ruiz, I.; Mastalerz, Maria; Cook, A.C.

    2007-01-01

    A recent paper by Sun [X. Sun, Spectrochim. Acta A 62 (1-3) (2005) 557] attempts to characterize a variety of liptinite, termed "barkinite", from Chinese Permian coals. The component identified does not appear to fundamentally differ from previously-described liptinite macerals included in the International Committee for Coal and Organic Petrology's system of maceral nomenclature. Further, chemical comparisons made with macerals from coals of different rank and age are flawed because the author did not account for changes in chemistry with rank or for the chemical changes associated with botanical changes through geologic time. The author has not satisfactorily proved his hypothesis that the component differs morphologically or chemically from known liptinite-group macerals. ?? 2006 Elsevier B.V. All rights reserved.

  15. On the Euclidean version of the photon number integral

    SciTech Connect

    Ruijsenaars, S.; Stodolsky, L.

    2008-02-15

    We reconsider the Euclidean version of the photon number integral introduced by Stodolsky [Acta Phys. Pol. B 33, 2659 (2002), e-print hep-th/02053131].This integral is well defined for any smooth non-self-intersecting curve in R{sup N}. Besides studying general features of this integral (including its conformal invariance), we evaluate it explicitly for the ellipse. The result is n{sub ellipse}=({xi}{sup -1}+{xi}){pi}{sup 2}, where {xi} is the ratio of the minor and major axes. This is in agreement with the previous result n{sub circle}=2{pi}{sup 2} and also with the conjecture that the minimum value of n for any plane curve occurs for the circle.

  16. Crystal structure of 2,4-di­nitro­phenyl 4-methyl­benzene­sulfonate: a new polymorph

    PubMed Central

    Cooley, Tyler A.; Riley, Sean; Biros, Shannon M.; Staples, Richard J.; Ngassa, Felix N.

    2015-01-01

    The title compound, C13H10N2O7S, was synthesized via a nucleophilic substitution reaction between 2,4-di­nitro­phenol and p-toluene­sulfonyl chloride. This crystal structure is a polymorph of CSD entry WUVYUH [Vembu et al. (2003). Acta Cryst, E59, o378–380]. The aromatic substituents on the sulfonate group are oriented gauche to one another with a C—O—S—C torsion angle of −62.0 (3)°. The supra­molecular features that contribute to the crystal stability are offset π–π [centroid–centroid distance = 3.729 (2) Å] and multiple C—H⋯O inter­actions. PMID:26396855

  17. Heterogeneous Crystal Nucleation: The Effect of Lattice Mismatch

    NASA Astrophysics Data System (ADS)

    Tóth, Gyula I.; Tegze, György; Pusztai, Tamás; Gránásy, László

    2012-01-01

    A simple dynamical density functional theory is used to investigate freezing of an undercooled liquid in the presence of a crystalline substrate. We find that the adsorption of the crystalline phase on the substrate, the contact angle, and the height of the nucleation barrier are nonmonotonic functions of the lattice constant of the substrate. We show that the free-growth-limited model of particle-induced freezing by Greer et al. [Acta Mater. 48, 2823 (2000)ACMAFD1359-645410.1016/S1359-6454(00)00094-X] is valid for larger nanoparticles and a small anisotropy of the interface free energy. Faceting due to the small size of the foreign particle or a high anisotropy decouples free growth from the critical size of homogeneous nuclei.

  18. A redetermination from the original data of the crystal structure of 2-amino-4,6-di-meth-oxy-pyrimidin-1-ium 4-amino-benzoate.

    PubMed

    Fábry, Jan

    2016-04-01

    The title structure, C6H9.5N3O2 (0.5+)·C7H6.5NO2 (0.5-), which might be named schematically as 2-amino-4,6-di-meth-oxy-pyrimidine-(μ2-hydrogen)-4-amino-benzoate to indicate a bridging H atom, has been redetermined from the data published by Thanigaimani, Mu-thiah & Lynch [Acta Cryst. (2006), E62, o2976-o2978]. The improvement of the present redetermination consists in a released geometry of the primary amine groups, which were originally assumed to be planar, as well as in a redetermination of the position of the hy-droxy H atom. This H atom, whose parameters were originally constrained, turns out to be situated about the centre of the O⋯N hydrogen bond in two disordered positions with occupancies of 0.5 each. PMID:27375878

  19. Crystal structure of bis­[tetra­kis­(tri­phenyl­phosphane-κP)silver(I)] (nitrilo­tri­acetato-κ4 N,O,O′,O′′)(tri­phenyl­phosphane-κP)argentate(I) with an unknown amount of methanol as solvate

    PubMed Central

    Noll, Julian; Korb, Marcus; Lang, Heinrich

    2016-01-01

    The structure of the title compound, [Ag(C18H15P)4]2[Ag(C6H6NO6)(C18H15P)], exhibits trigonal (P-3) symmetry, with a C 3 axis through all three complex ions, resulting in an asymmetric unit that contains one third of the atoms present in the formula unit. The formula unit thus contains two of the cations, one anion and disordered mol­ecules of methanol as the packing solvent. Attempts to refine the solvent model were unsuccessful, indicating uninter­pretable disorder. Thus, the SQUEEZE procedure in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9–18] was applied, accounting for 670 electrons per unit cell, representing approximately 18 mol­ecules of methanol in the formula unit. The stated crystal data for M r, μ etc do not take these into account. PMID:27006796

  20. Crystal structure of bis-[tetra-kis-(tri-phenyl-phosphane-κP)silver(I)] (nitrilo-tri-acetato-κ(4) N,O,O',O'')(tri-phenyl-phosphane-κP)argentate(I) with an unknown amount of methanol as solvate.

    PubMed

    Noll, Julian; Korb, Marcus; Lang, Heinrich

    2016-03-01

    The structure of the title compound, [Ag(C18H15P)4]2[Ag(C6H6NO6)(C18H15P)], exhibits trigonal (P-3) symmetry, with a C 3 axis through all three complex ions, resulting in an asymmetric unit that contains one third of the atoms present in the formula unit. The formula unit thus contains two of the cations, one anion and disordered mol-ecules of methanol as the packing solvent. Attempts to refine the solvent model were unsuccessful, indicating uninter-pretable disorder. Thus, the SQUEEZE procedure in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18] was applied, accounting for 670 electrons per unit cell, representing approximately 18 mol-ecules of methanol in the formula unit. The stated crystal data for M r, μ etc do not take these into account. PMID:27006796

  1. Evolution of local atomic structure during solidification of Al2Au liquid: An ab initio study

    SciTech Connect

    Xiong, L H; Lou, H B; Wang, X D; Debela, T T; Cao, Q P; Zhang, D X; Wang, S Y; Wang, C Z; Jiang, J Z

    2014-04-01

    The local atomic structure evolution in Al2Au alloy during solidification from 2000 K to 400 K was studied by ab initio molecular dynamics simulations and analyzed using the structure factor, pair correlation functions, bond angle distributions, the Honeycutt-Anderson (HA) index and Voronoi tessellation methods. It was found that the icosahedral-like clusters are negligible in the Al2Au stable liquid and supercooled liquid states, and the most abundant clusters are those having HA indices of 131 and 120 or Voronoi indices of < 0,4,4,0 >, < 0,3, 6,0 > and < 0,4,4,2 > with coordination numbers of 8, 9 and 10, respectively. These clusters are similar to the local atomic structures in the CaF2-type Al2Au crystal, revealing the existence of structure heredity between liquid and crystalline phase in Al2Au alloy. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  2. Genetics of hereditary large vessel diseases.

    PubMed

    Morisaki, Takayuki; Morisaki, Hiroko

    2016-01-01

    Recent progress in the study of hereditary large vessel diseases such as Marfan syndrome (MFS) have not only identified responsible genes but also provided better understanding of the pathophysiology and revealed possible new therapeutic targets. Genes identified for these diseases include FBN1, TGFBR1, TGFBR2, SMAD3, TGFB2, TGFB3, SKI, EFEMP2, COL3A1, FLNA, ACTA2, MYH11, MYLK and SLC2A10, as well as others. Their dysfunction disrupts the function of transforming growth factor-β (TGF-β) signaling pathways, as well as that of the extracellular matrix and smooth muscle contractile apparatus, resulting in progression of structural damage to large vessels, including aortic aneurysms and dissections. Notably, it has been shown that the TGF-β signaling pathway has a key role in the pathogenesis of MFS and related disorders, which may be important for development of strategies for medical and surgical treatment of thoracic aortic aneurysms and dissections. PMID:26446364

  3. Quantitative micro-Raman analysis of volcanic glasses: influence and correction of matrix effects

    NASA Astrophysics Data System (ADS)

    Di Muro, Andrea

    2014-05-01

    . Geochimica et Cosmochimica Acta, 74, 5641-5656. Mercier, M., Di Muro, A., Giordano, D., Métrich, N.,Pichavant, M., Clocchiatti, R., Montagnac, G. (2009) The influence of glass polymerization and oxidation on micro-Raman water analysis in alumino-silicate glasses. Geochimica et Cosmochimica Acta, 73, 197-217 Di Muro, A., Métrich, N., Mercier, M., Giordano, D., Massare, D., Montagnac, G. (2009) Micro-Raman determination of iron redox state in dry natural glasses : application to peralkaline rhyolites and basalts. Chemical Geology (Special volume on experimental techniques for the study of hydrothermal fluids and silicate melts) 259:78-88. Di Muro A, Villemant B, Montagnac G, Scaillet B, Reynard B (2006) The influence of glass composition on the determination of water content and speciation by Raman spectrometry. Geochimica and Cosmochimica Acta, 70, 2868-2884 Di Muro A, Giordano D., Villemant B, Montagnac G, Romano C. (2006) Influence of composition and thermal history of volcanic glasses on water content determination by microRaman spectrometry. Applied Geochemistry (Special volume on developments in analytical geochemistry). 21, 802-812. Application Di Muro, A., Staudacher, T., Ferrazzini, V., Villemant, B., Besson, P., Garofalo, C. (2014) Tracking magma injection in the Piton de la Fournaise volcanic edifice after the 2007 Summit Caldera Collapse by Pele's Hair Composition. Chapman Special Volume on Hawaiian volcanoes, AGU Books. Ardia, P., Di Muro, A., Giordano, D., Massare, D., Sanchez-Valle, C., Schmidt, M.W. (2014) Densification mechanisms of haplogranite glasses as a function of water content and pressure based on density and Raman data. Under review, submitted to Geochimica et Cosmochimica Acta. Métrich, N, Allard, P., Aiuppa, A., Bani, P., Bertagnini, A., Belhadj, O., Di Muro, A., Garaebiti, E., Massare, D., Parello, F., Shinohara, H. (2011) Magma and volatile feeding of post-caldera Yasur volcanism and block resurgence in Tanna island (Vanuatu arc). Journal of

  4. Triclinic polymorph of bis­(triphenyl­sil­yl) oxide toluene disolvate

    PubMed Central

    Purdy, Andrew P.; Smoot, Emily; Butcher, Ray J.; Kerr, Andrew

    2012-01-01

    A new polymorph of the title compound, C36H30OSi2·2C7H8, is reported, which is triclinic (P-1) instead of possessing the previously reported rhombohedral symmetry [Hönle et al. (1990). Acta Cryst. C46, 1982–1984]. Each of the –SiPh3 units are related by the inversion center. The Si—O—Si moiety is linear with the O atom sitting on an inversion center, and the O—Si—(toluene ring centroid) angle is 3.69 (15)°. Each toluene mol­ecule is 5.622 (2) Å from the Si atom and has its closest contacts with the phenyl rings outside of the van der Waals radii. PMID:22412504

  5. Dominance of foreign citations in Brazilian orthopedics journals☆☆☆

    PubMed Central

    Teixeira, Renan Kleber Costa; Yamaki, Vitor Nagai; Rosa, Rita de Cássia Rodrigues; de Barros, Rui Sergio Monteiro; Botelho, Nara Macedo

    2014-01-01

    Objective To evaluate whether there is any preference for citing journals from other countries to the detriment of Brazilian journals, in three Brazilian orthopedics journals. Methods All the references of articles published in 2011 by the journals Acta Ortopédica Brasileira, Coluna/Columna and Revista Brasileira de Ortopedia were evaluated to as certain how many of these came from Brazilian journals and how many from foreign journals. Results 3813 references distributed among 187 articles were analyzed. Out of this total, 306 (8.02%) were from Brazilian journals. There was no difference between the three journals analyzed. There were 76 articles (40.64%) without any citations of articles in Brazilian journals and only two articles (1%) cited more Brazilian articles than articles published elsewhere. Conclusion There is a need for Brazilian researchers to cite articles from Brazilian journals more often. PMID:26229879

  6. Multiscale model for phase transformation in magnetic shape memory alloy single crystals

    NASA Astrophysics Data System (ADS)

    Stoilov, Vesselin

    2006-03-01

    This paper investigates the nano-macro transition in magnetic shape memory alloy(MSMA) thin films using a recently developed sharp phase front-based three-dimensional (3D) constitutive model outlined by Stoilov (JSMS 2005), and originally proposed in the 1D context by Stoilov and Bhattacharyya (Acta Mat 2002). The key ingredient in the model is the recognition of martensitic variants as separate phases in a MSMA domain. Evolution of the interface between these phases is taken as an indicator of the process of reorientation in progress. A formulation of the Helmholtz free energy potential based on Ising model has been derived. The implications of the external magnetic field on the initiation of phase transformation are studied for various mechanical loading modes.

  7. Multiscale theory of thin film magnetic shape memory alloy microactuators

    NASA Astrophysics Data System (ADS)

    Stoilov, Vesselin

    2007-04-01

    This paper investigates the nano-macro transition in magnetic shape memory alloy(MSMA) thin films using a recently developed sharp phase front-based three-dimensional (3D) constitutive model outlined by Stoilov (JSMS 2007), and originally proposed in the 1D context by Stoilov and Bhattacharyya (Acta Mat 2002). The key ingredient in the model is the recognition of martensitic variants as separate phases in a MSMA domain. Evolution of the interface between these phases is taken as an indicator of the process of reorientation in progress. A formulation of the Helmholtz free energy potential based on Ising model has been derived. The implications of the external magnetic field on the initiation of phase transformation are studied for various mechanical loading modes.

  8. The Jubilee of Medical Informatics in Bosnia and Herzegovina - 20 Years Anniversary

    PubMed Central

    Masic, Izet

    2009-01-01

    CONFLICT OF INTEREST: NONE DECLARED Last two years, the health informatics profession celebrated five jubilees in Bosnia and Herzegovina: thirty years from the introduction of the first automatic manipulation of data, twenty years from the establishment of Society for Medical Informatics BiH, fifteen years from the establishment of the Scientific and Professional Journal of the Society for Medical Informatics of Bosnia and Herzegovina „Acta Informatica Medica“, fifteen years on from the establishment of the first Cathedra for Medical Informatics on Biomedical Faculties in Bosnia and Herzegovina and five years on from the introduction of the method of “Distance learning” in medical curriculum. The author of this article are eager to mark the importance of the above mentioned Anniversaries in the development of Health informatics in Bosnia and Herzegovina and have attempted, very briefly, to present the most significant events and persons with essential roles throughout this period. PMID:24133382

  9. Calculation of open and closed system elastic coefficients for multicomponent solids

    NASA Astrophysics Data System (ADS)

    Mishin, Y.

    2015-06-01

    Thermodynamic equilibrium in multicomponent solids subject to mechanical stresses is a complex nonlinear problem whose exact solution requires extensive computations. A few decades ago, Larché and Cahn proposed a linearized solution of the mechanochemical equilibrium problem by introducing the concept of open system elastic coefficients [Acta Metall. 21, 1051 (1973), 10.1016/0001-6160(73)90021-7]. Using the Ni-Al solid solution as a model system, we demonstrate that open system elastic coefficients can be readily computed by semigrand canonical Monte Carlo simulations in conjunction with the shape fluctuation approach. Such coefficients can be derived from a single simulation run, together with other thermodynamic properties needed for prediction of compositional fields in solid solutions containing defects. The proposed calculation approach enables streamlined solutions of mechanochemical equilibrium problems in complex alloys. Second order corrections to the linear theory are extended to multicomponent systems.

  10. The tholeiite-TTG connection during Eoarchean crust formation in Isua, southern West Greenland: the role of subduction processes

    NASA Astrophysics Data System (ADS)

    Hoffmann, J. E.; Münker, C.; Nagel, T. J.; Næraa, T.; Polat, A.; Rosing, M. T.

    2012-04-01

    thickened mafic crust to form the TTGs. The cause for the decoupled behavior of the Hf and Nd isotope compositions is most likely a subduction-related mantle source overprint, because Nd behaves more mobile in subduction components compared to the less mobile Hf (Hoffmann et al., 2011a). Other scenarios explaining the Hf-Nd decoupling may include cumulate segregation processes in an early magma ocean or an early metamorphic overprint during intrusion of the TTGs might also (Hoffmann et al., 2011a; Rizo et al., 2011). These scenarios are possible, however, they are only very difficult to reconcile with all observed trace element and isotope features of Isua rocks. Overall, we therefore propose that the most likely geodynamic setting to form the TTGs in the Isua region is an arc-arc collisional model, where the arc tholeiites melt at 10-20% of partial melting to form the TTGs. Caro, G., Bourdon, B. et al. (2006) Geochim. Cosmochim. Acta 70, 164-191. Hoffmann, J.E., Münker, C. et al. (2010) Geochim. Cosmochim. Acta 74, 7236-7260. Hoffmann, J.E., Münker, C. et al. (2011a) Geochim. Cosmochim. Acta 75, 6610-6628. Hoffmann, J.E., Münker, C. et al. (2011b) Geochim. Cosmochim. Acta 75, 4157-4178. Nagel, T., Hoffmann, J.E., Münker, C. (2012) Geology DOI: doi:10.1130/G32729.1. Næraa, T., Scherstén, A., et al., (submitted). Rizo, H., Boyet, M. et al. (2011) Earth Planet. Sci. Lett. 312, 267-279.

  11. [Contribution of the AMDP scale to quantitative psychopathology].

    PubMed

    Bobon, D

    1985-01-01

    The AMDP-System, elaborated by the Association for Methodology and Documentation in Psychiatry, comprises three anamnestic forms and two rating scales on present psychopathological and somatic state. Its success is increasing in the German-speaking and French-speaking countries. The author's thesis bears among others on the following aspects: importance of the naming of the items for the reliability of the underlying concepts, elaboration of a semi-structured interview and of a video methodology, programming of a new measure of interrater reliability in single cases, improvement of the somatic scale, and franco-belgian factor analyses showing the stability of the AMDP structure and the interest of anxiety items specific for the French version [Acta psychiat. belg., 85, 1-252 (1985)]. PMID:3887843

  12. Crystal structure of (E)-2-(4-chloro­benzyl­idene)-3,4-di­hydro­naphthalen-1(2H)-one: a second monoclinic polymorph

    PubMed Central

    Haroon, Muhammad; Akhtar, Tashfeen; Tahir, Muhammad Nawaz

    2015-01-01

    The title compound, C17H13ClO, is the second monoclinic polymorph to crystallize in the space group P21/c. The first polymorph crystallized with two independent mol­ecules in the asymmetric unit [Bolognesi et al. (1975 ▸). Acta Cryst. A31, S119; Z′ = 2; no atomic coordinates available], whereas the title compound has Z′ = 1. In the title polymorph, the dihedral angle between the plane of the benzene ring of the tetra­lone moiety and that of the 4-chloro­benzyl ring is 52.21 (11)°. The cyclo­hex-2-en-1-one ring of the tetra­lone moiety has a screw-boat conformation. In the crystal, mol­ecules are liked by pairs of C—H⋯π inter­actions forming inversion dimers. There are no other significant inter­molecular inter­actions present. PMID:26594452

  13. Molecular Simulations of the Diffusion of Uranyl Carbonate Species in Nanosized Mineral Fractures

    NASA Astrophysics Data System (ADS)

    Kerisit, S.; Liu, C.

    2010-12-01

    water and that of the electrolyte ions differ significantly from those in bulk aqueous solutions. We will then present MD simulations of the diffusion of a series of alkaline-earth uranyl carbonate species in aqueous solutions [7]. The MD simulations show that the alkaline-earth uranyl carbonate complexes have distinct water exchange dynamics, which could lead to different reactivities. Finally, we will present recent results on the diffusion and adsorption of uranyl carbonate species in intragrain micropores, modeled with the feldspar-water interfaces mentioned in the above, to help interpret the diffusion behavior of uranium in contaminated sediments. [1] Liu C. et al. Geochim. Cosmochim. Acta 68 4519 (2004) [2] McKinley J. P. et al. Geochim. Cosmochim. Acta 70 1873 (2006) [3] Liu C. et al. Water Resour. Res. 42 W12420 (2006) [4] Ilton E. S. et al. Environ. Sci. Technol. 42 1565 (2009) [5] Kerisit S. et al. Geochim. Cosmochim. Acta 72 1481 (2008) [6] Kerisit S. and Liu C. Environ. Sci. Technol. 43 777 (2009) [7] Kerisit S. and Liu C. Geochim. Cosmochim. Acta 74 4937 (2010)

  14. Pit Formation during the Self-Assembly of Dithiol Monolayers on Au(111)

    NASA Astrophysics Data System (ADS)

    Macdairmid, A. R.; Cappello, M. L.; Keeler, W. J.; Banks, J. T.; Gallagher, M. C.

    2000-03-01

    The formation of pits one gold atom deep during the growth of alkanethiol monolayers on Au(111), has been observed previously by others. Explanations for pit formation include etching of the substrate, or mass transport of gold atom + thiol molecule on the surface, due to changes in surface energy^1. We have investigated the structure of dithiothreitol (DTT) SAMs on Au(111). Ex situ STM measurements indicate similar pitting occurs during formation of the dithiol monolayer. The degree of pitting depends on exposure time, sample temperature during formation, and subsequent annealing of the sample. Pitting is enhanced considerasbly when DTT is coordinated with Ti, in fact DTT/Ti films exhibit considerable pit motion during STM imaging. ^1 F. Teran et al. Electrochimica Acta 44, 1053 (1998).

  15. CME for neurosurgeons in the Netherlands: the "quality" conferences.

    PubMed

    Mooij, J J A; Albrecht, K W; Grotenhuis, J A; Zeilstra, D J; Staal, M J; Koot, R W

    2009-02-01

    In 1993 the Netherlands Society for Neurosurgery started a yearly event, a "Quality Conference", specifically devoted to continuous medical education (CME). These conferences differ from "normal" scientific meetings, in the choice for specific topics, in the preparation with inquiries among all the Dutch neurosurgical centres, and in the way the results of these inquiries are discussed, preceded by lectures concerning the chosen topic by guest faculty and Dutch neurosurgeons. Each year's principal guest delivers the "Beks Lecture", named after the former professor in Neurosurgery in Groningen, Jan Beks. On several occasions, the foreign guests suggested to present this format for a larger neurosurgical forum. Therefore, it was decided to describe the various aspects of this format for CME in the Netherlands in a paper for Acta Neurochirugica. Examples of topics are given, a summary of two recent inquiries are presented and discussed, and the way of organizing such a conference including finance and the obligatory character are described. PMID:19194649

  16. Further results involving a class of generalized Hurwitz-Lerch zeta functions

    NASA Astrophysics Data System (ADS)

    Srivastava, H. M.; Gaboury, S.; Fugère, B.-J.

    2014-10-01

    In this paper, we present several new expansion formulas for a class of generalized Hurwitz-Lerch zeta functions which were introduced by Raina and Chhajed [R. K. Raina and P. K. Chhajed, "Certain Results Involving a Class of Functions Associated with the Hurwitz Zeta Function," Acta Math. Univ. Comenian. 73, 89-100 (2004)] and (more recently) by Srivastava et al. [H. M. Srivastava, M.-J. Luo, and R. K. Raina, "New Results Involving a Class of Generalized Hurwitz-Lerch Zeta Functions and Their Applications," Turkish J. Anal. Number Theory 1, 26-35 (2013)]. These expansion formulas are obtained with the help of some fractional calculus theorems such as the generalized Leibniz rules, the Taylorlike expansions in terms of different functions and the generalized chain rule. Several (known or new) special cases are also considered.

  17. Oxygen isotope heterogeneity of the mantle beneath the Canary Islands: a discussion of the paper of Gurenko et al.

    NASA Astrophysics Data System (ADS)

    Day, James M. D.; Macpherson, Colin G.; Lowry, David; Pearson, D. Graham

    2012-07-01

    Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) report laser-assisted fluorination (LF) and secondary ionization mass spectrometry (SIMS) 18O/16O datasets for olivine grains from the Canary Islands of Gran Canaria, Tenerife, La Gomera, La Palma and El Hierro. As with prior studies of oxygen isotopes in Canary Island lavas (e.g. Thirlwall et al. Chem Geol 135:233-262, 1997; Day et al. Geology 37:555-558, 2009, Geochim Cosmochim Acta 74:6565-6589, 2010), these authors find variations in δ18Ool (~4.6-6.0 ‰) beyond that measured for mantle peridotite olivine (Mattey et al. Earth Planet Sci Lett 128:231-241, 1994) and interpret this variation to reflect contributions from pyroxenite-peridotite mantle sources. Furthermore, Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) speculate that δ18Ool values for La Palma olivine grains measured by LF (Day et al. Geology 37:555-558, 2009, Geochim Cosmochim Acta 74:6565-6589, 2010) may be biased to low values due to the presence of altered silicate, possibly serpentine. The range in δ18Ool values for Canary Island lavas are of importance for constraining their origin. Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) took a subset (39 SIMS analyses from 13 grains from a single El Hierro lava; EH4) of a more extensive dataset (321 SIMS analyses from 110 grains from 16 Canary Island lavas) to suggest that δ18Ool is weakly correlated ( R 2 = 0.291) with the parameter used by Gurenko et al. (Earth Planet Sci Lett 277:514-524, 2009) to describe the estimated weight fraction of pyroxenite-derived melt ( Xpx). With this relationship, end-member δ18O values for HIMU-peridotite (δ18O = 5.3 ± 0.3 ‰) and depleted pyroxenite (δ18O = 5.9 ± 0.3 ‰) were defined. Although the model proposed by Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) implicates similar pyroxenite-peridotite mantle sources to those proposed by Day et al. (Geology 37:555-558, 2009, Geochim Cosmochim Acta 74:6565-6589, 2010

  18. A second polymorph of sodium di­hydrogen citrate, NaH2C6H5O7: structure solution from powder diffraction data and DFT comparison

    PubMed Central

    Rammohan, Alagappa; Kaduk, James A.

    2016-01-01

    The crystal structure of a second polymorph of sodium di­hydrogen citrate, Na+·H2C6H5O7 −, has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The powder pattern of the commercial sample used in this study did not match that corresponding to the known crystal structure [Glusker et al. (1965). Acta Cryst. 19, 561–572; refcode NAHCIT]. In this polymorph, the [NaO7] coordination polyhedra form edge-sharing chains propagating along the a axis, while in NAHCIT the octa­hedral [NaO6] groups form edge-sharing pairs bridged by two hy­droxy groups. The most notable difference is that in this polymorph one of the terminal carboxyl groups is deprotonated, while in NAHCIT the central carboxyl­ate group is deprotonated, as is more typical. PMID:27308058

  19. Groundwater-silicates Reaction Kinetics in the Navajo Sandstone Aquifer, Black Mesa, Arizona (Invited)

    NASA Astrophysics Data System (ADS)

    Zhu, C.

    2009-12-01

    laboratory experiments that complement the field study supports the hypothesis. Zhu, C. (2005) In situ feldspar dissolution rates in an aquifer. Geochimica et Cosmochimica Acta v. 69, no.6, 1435-1453, 2005. Zhu, C. Veblen, D.R., Blum, A.E, Chipera, S. (2006) Naturally weathered feldspar surfaces in the Navajo Sandstone aquifer, Black Mesa, Arizona: Electron microscopic characterization. Geochimica et Cosmochimica Acta v. 70, no.18, 4600-4616, 2006 doi:10.1016/j.gca.2006.07.013. Georg, R. B., Zhu, C. Reynolds, R.C., and Halliday, A.N. (2009) Stable silicon isotopes of groundwater, feldspars, and clay coatings in the Navajo Sandstone aquifer, Black Mesa, Arizona, USA. Geochimica et Cosmochimica Acta, v.73, 229-2241. Fu, Q., P ‡Lu, H. ‡Konishi, R. Dilmore, H. Xu, W. E. Seyfried, Jr., and C. Zhu (2009) Coupled alkali-feldspar Dissolution and Secondary Mineral Precipitation in Batch Systems: 1. New Experimental Data at 200°C and 300 bars. Chemical Geology, 91(3), 955-964. Zhu, C., and ‡Lu, P. (2009) Alkali Feldspar Dissolution and Secondary Mineral Precipitation in Batch Systems: 3. Saturation States of Product Minerals and Reaction Paths. Geochimica et Cosmochimica Acta. v.73, p.3171-3120. doi: 10.1016/j.gca.2009.03.015.

  20. Multicentre randomised controlled trials in obstetrics and gynaecology: an analysis of trends over three decades.

    PubMed

    Raza, A; Chien, P F W; Khan, K S

    2009-07-01

    To assess the trend in multicentre randomised controlled trials (RCTs), a database of 670 RCTs was assembled from four generic obstetric and gynaecological journals (Acta Obstetricia et Gynecologica Scandinavica, British Journal of Obstetrics & Gynaecology, Obstetrics & Gynecology and American Journal of Obstetrics & Gynecology) for 1975, 1980, 1985, 1990, 1995, 2000 and 2005. During this period, there was an inflationary trend with the proportion of published multicentre RCTs (from 12.9% in 1975 of all RCTs to 23.8% in 2005; P = 0.008). Multicentre RCTs had multiauthored publications (OR = 2.90; 95% CI 1.99-4.22) and more often received external funding (OR = 2.41; 95% CI 1.70-3.48) than single centre RCTs. The inflationary trend in multicentre RCTs requiring funding and collaboration represents the increasing complexity of medical research necessary to underpin evidence-based practice. PMID:19459867

  1. Redetermined crystal structure of N-(β-carb-oxy-eth-yl)-α-isoleucine.

    PubMed

    Chandrarekha, M; Srinivasan, N; Krishnakumar, R V

    2015-09-01

    Redetermination of the crystal structure of N-(β-carb-oxy-eth-yl)-α-isoleucine, C9H18N2O3, reported earlier by Nehls et al. [Acta Cryst. (2013), E69, o172-o173], was undertaken in which the ionization state assigned to the mol-ecule as unionized has been modified as zwitterionic in the present work. Single-crystal X-ray intensity data obtained from freshly grown crystals and freely refining the amino H atoms provide enhanced refinement and structural parameters, particularly the hydrogen-bonding scheme. N-H⋯O hydrogen bonds dominate the inter-molecular inter-actions along with a C-H⋯O hydrogen bond. The inter-molecular inter-action pattern is a three-dimensional network. The structure was refined as a two-component perfect inversion twin. PMID:26396893

  2. An Algorithm for Emulsion Stability Simulations: Account of Flocculation, Coalescence, Surfactant Adsorption and the Process of Ostwald Ripening

    PubMed Central

    Urbina-Villalba, German

    2009-01-01

    The first algorithm for Emulsion Stability Simulations (ESS) was presented at the V Conferencia Iberoamericana sobre Equilibrio de Fases y Diseño de Procesos [Luis, J.; García-Sucre, M.; Urbina-Villalba, G. Brownian Dynamics Simulation of Emulsion Stability In: Equifase 99. Libro de Actas, 1st Ed., Tojo J., Arce, A., Eds.; Solucion’s: Vigo, Spain, 1999; Volume 2, pp. 364–369]. The former version of the program consisted on a minor modification of the Brownian Dynamics algorithm to account for the coalescence of drops. The present version of the program contains elaborate routines for time-dependent surfactant adsorption, average diffusion constants, and Ostwald ripening. PMID:19399220

  3. Crystal structure of 4-(tri­methyl­germ­yl)benzoic acid

    PubMed Central

    Knauer, Lena; Barth, Eva R.; Golz, Christopher; Strohmann, Carsten

    2015-01-01

    The title compound, [Ge(CH3)3(C7H5O2)], was obtained as a by-product in the synthesis of the corresponding aldehyde. Two slightly different mol­ecules are present in the asymmetric unit. In both mol­ecules, the geometry of the aromatic ring plane is distorted by varying intensities. Additionally, the Ge atoms deviate from the mean aromatic ring planes. Whereas the distance of the Ge atom to the ring plane is only 0.101 (4) Å in the first mol­ecule, this distance is increased to 0.210 (4) Å in the second. In the crystal structure, centrosymmetric O—H⋯O hydrogen-bonded dimers are formed. The title compound is isostructural with the Si analogue [Haberecht et al. (2004 ▸). Acta Cryst. E60, o329–0330]. PMID:26090151

  4. A combinatorial chemistry approach to new materials for non-linear optics. II. 4-(Dimethylamino)cinnamaldehyde and a molecular complex of 4-methoxycinnamaldehyde with 2,4-dinitroaniline

    PubMed

    Nesterov; Timofeeva; Antipin; Clark

    2000-08-01

    The combinatorial chemistry approach has been used to synthesize an array of Schiff bases. The structures of five of these Schiff bases have been confirmed by X-ray analysis [Nesterov, Timofeeva, Borbulevych, Antipin & Clark (2000). Acta Cryst. C56, 971-975]. In two cases, the reaction conditions were not sufficient to obtain the products in question. In one case, a molecular complex, C(10)H(10)O(2).C(6)H(5)N(3)O(4), of the starting products 4-methoxycinnamaldehyde and 2,4-dinitroaniline was found. X-ray analysis revealed hydrogen-bond formation between the molecules of these reagents in the crystal. In the other case, X-ray analysis demonstrated that no chemical reaction occurred under the reaction conditions, and only one starting reagent, 4-(dimethylamino)cinnamaldehyde, C(11)H(13)NO, was found in the precipitate. PMID:10944294

  5. The mitochondrial permeability transition from yeast to mammals

    PubMed Central

    Azzolin, Luca; von Stockum, Sophia; Basso, Emy; Petronilli, Valeria; Forte, Michael A.; Bernardi, Paolo

    2010-01-01

    Regulated permeability changes have been detected in mitochondria across species. We review here their key features, with the goal of assessing whether a “permeability transition” similar to that observed in higher eukaryotes is present in other species. The recent discoveries (i) that treatment with cyclosporin A unmasks an inhibitory site for Pi [Basso et al. (2008) J. Biol Chem. 283, 26307–26311], the classical inhibitor of the permeability transition of yeast; and (ii) that under proper experimental conditions a matrix Ca2+-dependence can be demonstrated in yeast as well [Yamada et al. (2009) Biochim. Biophys. Acta 1787, 1486–1491] suggest that the mitochondrial permeability transition has been conserved during evolution. PMID:20398660

  6. Effects of thyroid hormones on the bypasses of the antimycin A block in the bc1 complex of rat liver mitochondria.

    PubMed

    Horrum, M A; Tobin, R B; Ecklund, R E

    1991-07-15

    The effect of thyroid hormones on the electron flow through the bc1 complex of rat liver mitochondria was studied using two dye bypasses of the Antimycin A block of the bc1 complex by the method of Alexandre and Lehninger (Biochim. Biophys. Acta 767:120; 1984). Bypass respiration rates with both DCIP (2,6-dichlorophenolindophenol) and TMPD (N,N,N',N'-tetramethyl-p-phenylenediamine dihydrochloride) were elevated in the hyperthyroid rats and depressed in the hypothyroid groups compared to the euthyroid controls. T3 treatment of hypothyroid rats returned the bypass rates to control levels in 24 hours with the TMPD dye but not for the DCIP. This further demonstrates that different portions of the bc1 complex respond individually to the thyroid state. PMID:1648915

  7. Longtime Well-posedness for the 2D Groma-Balogh Model

    NASA Astrophysics Data System (ADS)

    Wan, Renhui; Chen, Jiecheng

    2016-07-01

    In this paper, we consider the cauchy problem for the 2D Groma-Balogh model (Acta Mater 47:3647-3654, 1999). From the works Cannone et al. (Arch Ration Mech Anal 196:71-96, 2010) and El Hajj (Ann Inst Henri Poincaré Anal Nonlinéaire 27:21-35, 2010), one can see global well-posedness for this model is an open question. However, we can prove longtime well-posedness. In particular, we show that this model admits a unique solution with the lifespan T^star satisfying T^star log ^2(1+T^star )≳ ɛ ^{-2} if the initial data is of size ɛ . To achieve this, we first establish some new decay estimates concerning the operator e^{-{R}_{12}^2t} . Then, we prove the longtime well-posedness by utilizing the weak dissipation to deal with the nonlinear terms.

  8. About the hybrid Fourier syntheses: a probabilistic approach.

    PubMed

    Burla, Maria Cristina; Carrozzini, Benedetta; Cascarano, Giovanni Luca; Giacovazzo, Carmelo; Polidori, Giampiero

    2011-09-01

    The difference electron density has recently been revisited via the method of joint probability distribution functions [Burla et al. (2010). Acta Cryst. A 66, 347-361]. New Fourier coefficients were devised which were the basis of a new ab initio method for the solution of the phase problem (i.e. VLD, vive la difference). In this paper we study the joint probability distribution functions P(F, F(p), F(Q)), where F(Q) is the structure factor corresponding to the ideal hybrid Fourier synthesis ρ(Q) = τρ - ωρ(p) and τ and ω are any pair of real numbers. New Fourier coefficients for the calculations of any hybrid synthesis are obtained, and the properties of the corresponding electron-density maps are discussed. The first applications show the correctness of our theoretical approach and suggest possible applications in phasing procedures. PMID:21844649

  9. A simplification of the Kovarik formula

    NASA Astrophysics Data System (ADS)

    Chen, Yan-Ni; Du, Hong-Ke; Pang, Yong-Feng

    2007-07-01

    Let P,Q be two idempotents on a Hilbert space. Z.V. Kovarik (Z.V. Kovarik, Similarity and interpolation between projectors, Acta Sci. Math. (Szeged) 39 (1977) 341-351) showed that when P+Q-I is invertible, the formula K(P,Q)=P(P+Q-I)-2Q gives the only idempotent such that , , where and denote the nullspace and the range of a bounded linear operator T on a Hilbert space, respectively. This formula was later extended to the context of Banach algebras and used in 1983 by J. Esterle to show that two homotopic idempotents may always be connected by a polynomial idempotent valued path. In the present paper, we give a simplification of Kovarik's original formula and one natural generalization of it.

  10. Retracing diagenetic processes in marine porewaters using Ca isotopes

    NASA Astrophysics Data System (ADS)

    Ockert, C.; Teichert, B. M.; Kaufhold, S.; Gussone, N. C.

    2012-12-01

    ammonium and δ44/40Ca depends on the presence of clay minerals in the lithology, displaying a better fit when clay minerals occur. These findings resolve that exchange of Ca with marine sediments has an important effect on the porewater isotopy which must be considered when interpreting Ca isotope porewater profiles. References: Fantle MS and DePaolo DJ (2007) Ca isotopes in carbonate sediment and pore fluid from ODP Site 807A: The Ca2+(aq)-calcite equilibrium fractionation factor and calcite recrystallization rates in Pleistocene sediments. Geochimica et Cosmochimica Acta 71: 2524-2546. Skulan J, DePaolo DJ and Owens TL (1997) Biological control of calcium isotopic abundances in the global calcium cycle. Geochimica et Cosmochimica Acta 61: 2505-2510. Teichert BMA, Gussone N, Torres ME (2009) Controls on calcium isotope fractionation in sedimentary porewaters. Earth and Planetary Science Letters 279: 373-382. Turchyn A and DePaolo DJ (2011) Calcium isotope evidene for suppression of carbonate dissolution in carbonate bearing organic rich sediments. Geochimica et Cosmochimica Acta 75: 7081-7098. Zhu P, MacDougall JD (1998) Calcium isotopes in the marine environment and the oceanic calcium cycle. Geochimica et Cosmochimica Acta 62:1691-1698.

  11. Surface-force-induced deformations of monodisperse polystyrene spheres on planar silicon substrates

    NASA Astrophysics Data System (ADS)

    Rimai, D. S.; DeMejo, L. P.; Bowen, R. C.

    1990-12-01

    The contact radii between polystyrene spheres, having diameters between approximately 1.5 and 12 μm, and polished silicon wafers, arising from adhesion forces, were determined using scanning electron microscopy. It was found that the contact radius varied approximately as the square root of the particle radius. This dependence is consistent with nonelastic response models of adhesion, such as those proposed by Krupp [H. Krupp, Adv. Colloid Interface Sci. 1, 111 (1967)] and by Maugis and Pollock [D. Maugis and H. M. Pollock, Acta Metall. 32, 1323 (1984)], but is inconsistent with various elastic response models which assume Hertzian deformations. The experimentally determined contact radii are also compared to those obtained for polystyrene spheres on a polyurethane substrate [D. S. Rimai, L. P. DeMejo, and R. C. Bowen, J. Appl. Phys. 66, 3574 (1989)].

  12. 3-[1-(3-Hy­droxy­benz­yl)-1H-benzimid­azol-2-yl]phenol dimethyl sulfoxide monosolvate

    PubMed Central

    Quezada-Miriel, Magdalena; Avila-Sorrosa, Alcives; German-Acacio, Juan Manuel; Reyes-Martínez, Reyna; Morales-Morales, David

    2012-01-01

    Crystals of the title compound were obtained as a 1:1 dimethyl sulfoxide solvate, C20H16N2O2·C2H6O. The mol­ecular conformation of the organic mol­ecule is similar to that in the previously reported unsolvated structure [Eltayeb et al. (2009 ▶). Acta Cryst. E65, o1374–o1375]. Thus, the dihedral angles formed by the benzimidazole moiety with the two benzene rings are 57.54 (4) and 76.22 (5)°, and the dihedral angle between the benzene rings is 89.23 (5)°. In the crystal, a three-dimensional network features O—H⋯O, O—H⋯N and O—H⋯S hydrogen bonds, as well as C—H⋯O and C—H⋯π inter­actions. PMID:23125815

  13. Direct analysis of blood serum by total reflection X-ray fluorescence spectrometry and application of an artificial neural network approach for cancer diagnosis*1

    NASA Astrophysics Data System (ADS)

    Hernández-Caraballo, Edwin A.; Marcó-Parra, Lué M.

    2003-12-01

    Iron, copper, zinc and selenium were determined directly in serum samples from healthy individuals ( n=33) and cancer patients ( n=27) by total reflection X-ray fluorescence spectrometry using the Compton peak as internal standard [L.M. Marcó P. et al., Spectrochim. Acta Part B 54 (1999) 1469-1480]. The standardized concentrations of these elements were used as input data for two-layer artificial neural networks trained with the generalized delta rule in order to classify such individuals according to their health status. Various artificial neural networks, comprising a linear function in the input layer, a hyperbolic tangent function in the hidden layer and a sigmoid function in the output layer, were evaluated for such a purpose. Of the networks studied, the (4:4:1) gave the highest estimation (98%) and prediction rates (94%). The latter demonstrates the potential of the total reflection X-ray fluorescence spectrometry/artificial neural network approach in clinical chemistry.

  14. Second monoclinic form of (E)-3-(4-fluoro­phen­yl)-1-phenyl­prop-2-en-1-one

    PubMed Central

    Arias-Ruiz, Saira N.; Romero, Nancy; Lobato-García, Carlos E.; Gómez-Rivera, Abraham; Mendoza, Angel

    2013-01-01

    The unit-cell dimensions and space group of the second monoclinic polymorph of the title compound, C15H11FO, differ from those of the previously reported form [Jing (2009 ▶). Acta Cryst. E65, o2515]. The title compound shows an E conformation of the C=C bond with the 4-fluoro­phenyl group opposite to the benzoyl group. The torsion angle of between the planes of the 4-fluoro­phenyl and benzoyl groups is 10.53 (6)°. In the crystal, weak C—H⋯O and C—H⋯F inter­actions form a cross-linked packing motif, building sheets parallel to (-102). PMID:24454121

  15. A Priori Bound on the Velocity in Axially Symmetric Navier-Stokes Equations

    NASA Astrophysics Data System (ADS)

    Lei, Zhen; Navas, Esteban A.; Zhang, Qi S.

    2016-01-01

    Let v be the velocity of Leray-Hopf solutions to the axially symmetric three-dimensional Navier-Stokes equations. Under suitable conditions for initial values, we prove the following a priori bound |v(x, t)| ≤ C |ln r|^{1/2}/r^2, qquad 0 < r ≤ 1/2, where r is the distance from x to the z axis, and C is a constant depending only on the initial value. This provides a pointwise upper bound (worst case scenario) for possible singularities, while the recent papers (Chiun-Chuan et al., Commun PDE 34(1-3):203-232, 2009; Koch et al., Acta Math 203(1):83-105, 2009) gave a lower bound. The gap is polynomial order 1 modulo a half log term.

  16. Comparison of Monte Carlo simulations of cytochrome b6f with experiment using Latin hypercube sampling.

    PubMed

    Schumaker, Mark F; Kramer, David M

    2011-09-01

    We have programmed a Monte Carlo simulation of the Q-cycle model of electron transport in cytochrome b(6)f complex, an enzyme in the photosynthetic pathway that converts sunlight into biologically useful forms of chemical energy. Results were compared with published experiments of Kramer and Crofts (Biochim. Biophys. Acta 1183:72-84, 1993). Rates for the simulation were optimized by constructing large numbers of parameter sets using Latin hypercube sampling and selecting those that gave the minimum mean square deviation from experiment. Multiple copies of the simulation program were run in parallel on a Beowulf cluster. We found that Latin hypercube sampling works well as a method for approximately optimizing very noisy objective functions of 15 or 22 variables. Further, the simplified Q-cycle model can reproduce experimental results in the presence or absence of a quinone reductase (Q(i)) site inhibitor without invoking ad hoc side-reactions. PMID:21221830

  17. Data analysis and other considerations concerning the study of precipitation in Al–Mg–Si alloys by Atom Probe Tomography

    PubMed Central

    Zandbergen, M.W.; Xu, Q.; Cerezo, A.; Smith, G.D.W.

    2015-01-01

    Atom Probe Tomography (APT) analysis and hardness measurements were used to characterize the early stages of precipitation in an Al–0.51 at%Mg–0.94 at%Si alloy as reported in the accompanying Acta Materialia paper [1]. The changes in microstructure were investigated after single-stage or multi-stage heat treatments including natural ageing at 298 K (NA), pre-ageing at 353 K (PA), and automotive paint-bake ageing conditions at 453 K (PB). This article provides Supporting information and a detailed report on the experimental conditions and the data analysis methods used for this investigation. Careful design of experimental conditions and analysis methods was carried out to obtain consistent and reliable results. Detailed data on clustering for prolonged NA and PA treatments have been reported. PMID:26958619

  18. Properties of X-ray resonant scattering in the Bragg case revealed on the Riemann surface.

    PubMed

    Saka, Takashi

    2016-07-01

    Continuing the work described in the previous paper [Saka (2016). Acta Cryst. A72, 338-348], the dynamical theory for perfect crystals in the Bragg case is reformulated using the Riemann surface. In particular, diffraction under resonant scattering conditions is investigated. The characteristic features of the dispersion surface and the rocking curve are analytically revealed using four parameters, which are the real and imaginary parts of two quantities specifying the degree of departure from the exact Bragg conditions and the reflection strength. Characteristic properties that have been deduced through numerical analysis are derived analytically using these four parameters. Visualization of the geometric relationships between the four parameters on the Riemann surface is useful for understanding many properties such as symmetry and sharpness of the rocking curve under special conditions. Therefore, employing the Riemann surface is instructive for numerical analysis and useful for understanding dynamical diffraction in the Bragg case. PMID:27357849

  19. A triclinic polymorph of (E)-2-(4-iso­butyl­phen­yl)-N′-[1-(4-nitro­phen­yl)ethyl­idene]propano­hydrazide

    PubMed Central

    Manjunath, B. C.; Madan Kumar, S.; Vinayaka, A. C.; Jayasheelan, S.; Sadashiva, M. P.; Lokanath, N. K.

    2013-01-01

    The asymmetric unit of the triclinic polymorph of the title compound, C21H25N3O3, consists of two mol­ecules, whereas for the monoclinic polymorph Z′ = 1 [Fun et al. (2009 ▶). Acta Cryst. E65, o445]. The two mol­ecules exhibit an E configuration with respect to the C=N bond. The mol­ecules are linked into dimers by N—H⋯O and C—H⋯O hydrogen bonds forming R 2 2(8) ring motifs. In addition, π–π inter­actions occur between nitro­phenyl groups [minimum centroid–centroid distance 3.940 (2) Å], stacking the molecules along the ac plane. PMID:24109404

  20. Engineering an artificial amoeba propelled by nanoparticle-triggered actin polymerization.

    PubMed

    Yi, Jinsoo; Schmidt, Jacob; Chien, Aichi; Montemagno, Carlo D

    2009-02-25

    We have engineered an amoeba system combining nanofabricated inorganic materials with biological components, capable of propelling itself via actin polymerization. The nanofabricated materials have a mechanism similar to the locomotion of the Listeria monocytogenes, food poisoning bacteria. The propulsive force generation utilizes nanoparticles made from nickel and gold functionalized with the Listeria monocytogenes transmembrane protein, ActA. These Listeria-mimic nanoparticles were in concert with actin, actin binding proteins, ATP (adenosine triphosphate) and encapsulated within a lipid vesicle. This system is an artificial cell, such as a vesicle, where artificial nanobacteria and actin polymerization machinery are used in driving force generators inside the cell. The assembled structure was observed to crawl on a glass surface analogously to an amoeba, with the speed of the movement dependent on the amount of actin monomers and ATP present. PMID:19417437

  1. Engineering an artificial amoeba propelled by nanoparticle-triggered actin polymerization

    NASA Astrophysics Data System (ADS)

    Yi, Jinsoo; Schmidt, Jacob; Chien, Aichi; Montemagno, Carlo D.

    2009-02-01

    We have engineered an amoeba system combining nanofabricated inorganic materials with biological components, capable of propelling itself via actin polymerization. The nanofabricated materials have a mechanism similar to the locomotion of the Listeria monocytogenes, food poisoning bacteria. The propulsive force generation utilizes nanoparticles made from nickel and gold functionalized with the Listeria monocytogenes transmembrane protein, ActA. These Listeria-mimic nanoparticles were in concert with actin, actin binding proteins, ATP (adenosine triphosphate) and encapsulated within a lipid vesicle. This system is an artificial cell, such as a vesicle, where artificial nanobacteria and actin polymerization machinery are used in driving force generators inside the cell. The assembled structure was observed to crawl on a glass surface analogously to an amoeba, with the speed of the movement dependent on the amount of actin monomers and ATP present.

  2. A redetermination of the structure of poly[[μ4-(R)-2-ammonio-3-sulfonato­propano­ato]aqua­sodium], originally reported as poly[[μ7-l-cysteato(2−)]disodium

    PubMed Central

    Brown, I. David

    2012-01-01

    The structure originally reported as poly[[μ7-l-cysteato(2−)]disodium], [Na2(C3H5NO5S)]n [Liu (2002). Acta Cryst. E67, m1346–m1347], has been redetermined with one of the sodium atoms replaced with a water mol­ecule and an additional proton attached to the amine group, resulting in the revised formula [Na{CO2CH(CH2SO3)NH3}(H2O)]n. The agreement index, wR, has been reduced from 0.159 to 0.087 and the global instability index from 0.56 vu (valence units) to the acceptable value of 0.11 vu. PMID:22606082

  3. Cybip, a starfish cyclin B-binding protein, is involved in meiotic M-phase exit.

    PubMed

    Offner, Nicolas; Derancourt, Jean; Lozano, Jean Claude; Schatt, Philippe; Picard, André; Peaucellier, Gérard

    2003-01-01

    We designed a screen to identify starfish oocyte proteins able to bind monomeric cyclin B by affinity chromatography on a cyclin B splice variant displaying low affinity for cdc2. We identified a 15kDa protein previously described as a cdk-binding protein [Biochim. Biophys. Acta Mol. Cell Res. 1589 (2002) 219-231]. Cybip is encoded by a single polymorphic gene and the native protein is matured by cleaving a signal peptide. We firmly establish the fact that it is a true cyclin B-binding protein, since the recombinant protein binds recombinant cyclin B in absence of any cdk. Finally, we show that the microinjection of GST-cybip, and of anti-cybip antibody, in maturing starfish oocytes, inhibits H1 kinase and MPF inactivation, and first polar body emission. PMID:12480530

  4. Barrow, Leibniz and the geometrical proof of the fundamental theorem of the calculus.

    PubMed

    Nauenberg, Michael

    2014-07-01

    In 1693, Gottfried Wilhelm Leibniz published in the Acta Eruditorum a geometrical proof of the fundamental theorem of the calculus. It is shown that this proof closely resembles Isaac Barrow's proof in Proposition 11, Lecture 10, of his Lectiones Geometricae, published in 1670. This comparison provides evidence that Leibniz gained substantial help from Barrow's book in formulating and presenting his geometrical formulation of this theorem. The analysis herein also supports the work of J. M. Child, who in 1920 studied the early manuscripts of Leibniz and concluded that he had frequently copied his diagrams from Barrow's book, but without acknowledgement. It is also shown that the diagram of Leibniz associated with his 1693 proof has often been reproduced with errors that make some aspects of his text difficult to comprehend. PMID:24908795

  5. Characterization and expression of two genes encoding isoforms of a putative Na, K-ATPase in the chytridiomycete Blastocladiella emersonii.

    PubMed

    Fietto, Luciano Gomes; Pugliese, Luciana; Gomes, Suely Lopes

    2002-06-01

    A P-type ATPase gene (BePAT1) from the aquatic fungus Blastocladiella emersonii, which surprisingly showed high similarity with the alpha-subunit of Na, K-ATPases from animal cells, has been reported recently [Biochim. Biophys. Acta 1383 (1998) 183]. In the present study, we describe the characterization of a second gene, denominated BePAT2, and show that these two genes have a different intron-exon structure but encode putative proteins with greater than 90% amino acid identity. Northern blot and multiplex reverse transcription and polymerase chain reaction (RT-PCR) assays have revealed that BePAT1 and BePAT2 genes have a non-coordinate, developmentally regulated expression during B. emersonii life cycle. Phosphoenzyme formation experiments using the immunopurified enzymes have indicated the presence of a Na, K-ATPase-like activity. Furthermore, immunofluorescence studies using B. emersonii zoospores localized the ATPases on the plasma membrane of these cells. PMID:12031485

  6. Thermo-hydrologic modelling of permafrost with OpenFOAM®: perspectives of applications to the study of weathering in boreal areas

    NASA Astrophysics Data System (ADS)

    Laurent, Orgogozo; Oleg S., Pokrovsky; Yves, Goddéris; Christophe, Grenier; Jerome, Viers; David, Labat; Stephane, Audry; Anatoly, Prokushkin

    2015-04-01

    this tool for the study of the weathering processes in boreal areas will be discussed. [1] Pokrovsky O.S. et al., 2005. Geochimi. Cosmochim. Acta 69. [2] Pokrovsky O.S. et al., 2006. Geochimi. Cosmochim. Acta 70. [3] Bagard M.-L. et al., 2011. Geochim. Cosmochim. Acta 75. [4] Berner R.A., 1992. Geochim. Cosmochim. Acta 56. [5] Zimov S.A. et al., 2006. Science 312. [6] http://www.openfoam.com/ [7] Orgogozo et al., 2014. Comput. Phys. Commun. 185. [8] Beaulieu E. et al., 2010. Geochem. Geophys. Geosyst. 11. [9] Goddéris Y. et al., 2012. Biogeosciences Discuss. 9. [10] Grenier C. et al., 2013. AGU, Fall Meeting 2013, abstract #C44B-06 [11] https://wiki.lsce.ipsl.fr/interfrost/doku.php?id=home [12] Orgogozo L. et al., 2014. In "Permafrost: Distribution, Composition and Impacts on Infrastructure and Ecosystems", ed. O.S. Pokrovsky, Nova Publishers.

  7. On the efficiency of VBSCF algorithms, a comment on "An efficient algorithm for energy gradients and orbital optimization in valence bond theory".

    PubMed

    van Lenthe, J H; Broer-Braam, H B; Rashid, Z

    2012-03-30

    We comment on the paper [Song et al., J. Comput. Chem. 2009, 30, 399]. and discuss the efficiency of the orbital optimization and gradient evaluation in the Valence Bond Self Consistent Field (VBSCF) method. We note that Song et al. neglect to properly reference Broer et al., who published an algorithm [Broer and Nieuwpoort, Theor. Chim. Acta 1988, 73, 405] to use a Fock matrix to compute a matrix element between two different determinants, which can be used for an orbital optimization. Further, Song et al. publish a misleading comparison with our VBSCF algorithm [Dijkstra and van Lenthe, J. Chem. Phys. 2000, 113, 2100; van Lenthe et al., Mol. Phys. 1991, 73, 1159] to enable them to favorably compare their algorithm with ours. We give detail timings in terms of different orbital types in the calculation and actual timings for the example cases. PMID:22278948

  8. A family of ternary decagonal tilings

    NASA Astrophysics Data System (ADS)

    Fujita, Nobuhisa

    2010-04-01

    A new family of decagonal quasiperiodic tilings are constructed by the use of generalized point substitution processes, which is a new substitution formalism developed by the author [N. Fujita, Acta Cryst. A 65, 342 (2009)]. These tilings are composed of three prototiles: an acute rhombus, a regular pentagon and a barrel shaped hexagon. In the perpendicular space, these tilings have windows with fractal boundaries, and the windows are analytically derived as the fixed sets of the conjugate maps associated with the relevant substitution rules. It is shown that the family contains an infinite number of local isomorphism classes which can be grouped into several symmetry classes (e.g., C10, D5, etc.). The member tilings are transformed into one another through collective simpleton flips, which are associated with the reorganization in the window boundaries.

  9. Chronology of meteorites and the early solar system

    NASA Astrophysics Data System (ADS)

    Krot, Alexander N.; Bizzarro, Martin

    2009-09-01

    Understanding the chronology of the chondritic and differentiated meteorites can potentially important constraints on the accretion and origin of the solar system planets, life-time of our protoplanetary disk and circumstellar disks around solar mass stars, and astrophysical setting of the solar system formation. The special issue of Geochimica et Cosmochimica Acta consists of invited and contributed papers presented at the Workshop on The Chronology of Meteorites and the Early Solar System, Kauai, 2007 and is honoring the outstanding contributions of C.J. Allégre, G.W. Lugmair, L.E. Nyquist, D.A. Papanastassiou, and G.J. Wasserburg to our understanding of the chronology of the early Solar System.

  10. Helical plasma striations in liners in the presence of an external axial magnetic field

    NASA Astrophysics Data System (ADS)

    Atoyan, L.; Hammer, D. A.; Kusse, B. R.; Byvank, T.; Cahill, A. D.; Greenly, J. B.; Pikuz, S. A.; Shelkovenko, T. A.

    2016-02-01

    Awe et al. found on the 20 MA Z machine [Acta Phys. Pol. A 115, 956 (2009)] that applying an externally generated axial magnetic field to an imploding liner leads to a helical pattern in the liner when viewed with soft x-ray radiography ([Phys. Rev. Lett. 111, 235005 (2013)] and [Phys. Plasmas 21, 056303 (2014)]). Here, we show that this phenomenon is also observed in extreme ultraviolet self-emission images of 10 mm long cylindrical metal liners having varying diameters and varying wall thicknesses on a 1 MA, 100-200 ns pulsed power generator. The magnetic field in these experiments is created using either twisted return current wires positioned close to the liner, generating a time-varying Bz, or a Helmholtz coil, generating a steady-state Bz.

  11. Bcl-2 mutants with restricted subcellular location reveal spatially distinct pathways for apoptosis in different cell types.

    PubMed Central

    Zhu, W; Cowie, A; Wasfy, G W; Penn, L Z; Leber, B; Andrews, D W

    1996-01-01

    Human Bcl-2 is located in multiple intracellular membranes when expressed in MDCK and Rat-1/myc cells. We restricted expression to the endoplasmic reticulum or mitochondria by exchanging the Bcl-2 carboxy-terminal insertion sequence for an equivalent sequence from cytochrome b5 or ActA, respectively. MDCK cells are protected from serum deprivation-induced apoptosis by both wild-type Bcl-2 and the mutant targeted to mitochondria but not by the mutant targeted to endoplasmic reticulum. In contrast, when expressed in Rat-1/myc cells, the Bcl-2 mutant located at the endoplasmic reticulum is more effective than that targeted to mitochondria. In MDCK cells both mutants bind Bax as effectively as wild-type, demonstrating that Bax binding is not sufficient to prevent apoptosis. Images PMID:8861942

  12. Cloning and Heterologous Expression of the Grecocycline Biosynthetic Gene Cluster.

    PubMed

    Bilyk, Oksana; Sekurova, Olga N; Zotchev, Sergey B; Luzhetskyy, Andriy

    2016-01-01

    Transformation-associated recombination (TAR) in yeast is a rapid and inexpensive method for cloning and assembly of large DNA fragments, which relies on natural homologous recombination. Two vectors, based on p15a and F-factor replicons that can be maintained in yeast, E. coli and streptomycetes have been constructed. These vectors have been successfully employed for assembly of the grecocycline biosynthetic gene cluster from Streptomyces sp. Acta 1362. Fragments of the cluster were obtained by PCR and transformed together with the "capture" vector into the yeast cells, yielding a construct carrying the entire gene cluster. The obtained construct was heterologously expressed in S. albus J1074, yielding several grecocycline congeners. Grecocyclines have unique structural moieties such as a dissacharide side chain, an additional amino sugar at the C-5 position and a thiol group. Enzymes from this pathway may be used for the derivatization of known active angucyclines in order to improve their desired biological properties. PMID:27410036

  13. A spectroscopic and computational study of Al(III) complexes in cryolite melts: Effect of cation nature

    NASA Astrophysics Data System (ADS)

    Nazmutdinov, Renat R.; Zinkicheva, Tamara T.; Vassiliev, Sergey Yu.; Glukhov, Dmitrii V.; Tsirlina, Galina A.; Probst, Michael

    2013-02-01

    Lithium, sodium and potassium cryolite melts are probed by Raman spectroscopy in a wide range of the melt composition. The experimental data demonstrate a slight red shift of main peaks and a decrease of their half-widths in the row Li+, Na+, K+. Quantum chemical modelling of the systems is performed at the density functional theory level. The ionic environment is found to play a crucial role in the energy of fluoroaluminates. Potential energy surfaces describing the formation/dissociation of certain complex species, as well as model Raman spectra are constructed and compared with those obtained recently for sodium containing cryolite melts (R.R. Nazmutdinov, et al., Spectrochim, Acta A 75 (2010) 1244.). The calculations show that the cation nature affects the geometry of the ionic associates as well as the equilibrium and kinetics of the complexation processes. This enables to interpret both original experimental data and those reported in literature.

  14. A spectroscopic and computational study of Al(III) complexes in cryolite melts: Effect of cation nature

    PubMed Central

    Nazmutdinov, Renat R.; Zinkicheva, Tamara T.; Vassiliev, Sergey Yu.; Glukhov, Dmitrii V.; Tsirlina, Galina A.; Probst, Michael

    2013-01-01

    Lithium, sodium and potassium cryolite melts are probed by Raman spectroscopy in a wide range of the melt composition. The experimental data demonstrate a slight red shift of main peaks and a decrease of their half-widths in the row Li+, Na+, K+. Quantum chemical modelling of the systems is performed at the density functional theory level. The ionic environment is found to play a crucial role in the energy of fluoroaluminates. Potential energy surfaces describing the formation/dissociation of certain complex species, as well as model Raman spectra are constructed and compared with those obtained recently for sodium containing cryolite melts (R.R. Nazmutdinov, et al., Spectrochim, Acta A 75 (2010) 1244.). The calculations show that the cation nature affects the geometry of the ionic associates as well as the equilibrium and kinetics of the complexation processes. This enables to interpret both original experimental data and those reported in literature. PMID:23408115

  15. A spectroscopic and computational study of Al(III) complexes in cryolite melts: Effect of cation nature.

    PubMed

    Nazmutdinov, Renat R; Zinkicheva, Tamara T; Vassiliev, Sergey Yu; Glukhov, Dmitrii V; Tsirlina, Galina A; Probst, Michael

    2013-02-01

    Lithium, sodium and potassium cryolite melts are probed by Raman spectroscopy in a wide range of the melt composition. The experimental data demonstrate a slight red shift of main peaks and a decrease of their half-widths in the row Li(+), Na(+), K(+). Quantum chemical modelling of the systems is performed at the density functional theory level. The ionic environment is found to play a crucial role in the energy of fluoroaluminates. Potential energy surfaces describing the formation/dissociation of certain complex species, as well as model Raman spectra are constructed and compared with those obtained recently for sodium containing cryolite melts (R.R. Nazmutdinov, et al., Spectrochim, Acta A 75 (2010) 1244.). The calculations show that the cation nature affects the geometry of the ionic associates as well as the equilibrium and kinetics of the complexation processes. This enables to interpret both original experimental data and those reported in literature. PMID:23408115

  16. Siderophore-mediated oxidation of Ce and fractionation of HREE by Mn (hydr)oxide-coprecipitation and sorption on MnO2: Experimental evidence for negative Ce-anomalies in abiogenic manganese precipitates

    NASA Astrophysics Data System (ADS)

    Krämer, Dennis; Tepe, Nathalie; Bau, Michael

    2014-05-01

    )oxides (e.g., Tanaka et al., 2010, Loges et al., 2012). Our experimental results demonstrate that biogenic organic ligands such as hydroxamate siderophores, may produce solutions with positive Ce anomaly (Bau et al., 2013) and may even counteract the surface oxidation of Ce on Mn (hydr)oxides. References Bau, M., Tepe, N., Mohwinkel, D., 2013. Siderophore-promoted transfer of rare earth elements and iron from volcanic ash into glacial meltwater, river and ocean water. Earth Planet. Sci. Lett. 364, 30-36. Christenson E. A. and Schijf J. (2011) Stability of YREE complexes with the trihydroxamate siderophore desferrioxamine B at seawater ionic strength. Geochim. Cosmochim. Acta 75, 7047-7062. Loges, A., Wagner, T., Barth, M., Bau, M., Göb, S., and Markl, G. 2012. Negative Ce anomalies in Mn oxides: The role of Ce4+ mobility during water-mineral interaction. Geochimica and Cosmochimica Acta 86, 296-317 Ohta A. and Kawabe I. (2001) REE (III) adsorption onto Mn dioxide (delta-MnO2) and Fe oxyhydroxide: Ce(III) oxidation by delta-MnO2. Geochim. Cosmochim. Acta 65, 695-703. Tanaka K., Tani Y., Takahashi Y., Tanimizu M., Suzuki Y., Kozai N. and Ohnuki T. (2010) A specific Ce oxidation process during sorption of rare earth elements on biogenic Mn oxide produced by Acremonium sp. strain KR21-2. Geochim. Cosmochim. Acta 74, 5463-5477.

  17. 3-[2-(3-Methyl­quinoxalin-2-yl­oxy)eth­yl]-1,3-oxazolidin-2-one

    PubMed Central

    Ahoya, Caleb Anothane; Bouhfid, Rachid; Daouda, Ballo; Essassi, El Mokhtar; El Ammari, Lahcen

    2010-01-01

    Two isomers were isolated during the reaction between 3-methyl­quinoxalin-2-one and bis­(2-chloro­ethyl)amine hydro­chloride. The crystal structure of one isomer has already been reported [Caleb, Bouhfid, Essassi & El Ammari (2009). Acta Cryst. E65, o2024–o2025], while that of the second isomer is the subject of this work. The title compound, C14H15N3O3, has a new structure containing oxazolidine and quinoxaline rings linked by an eth­oxy group. The main difference between the two isomers is the position of the oxazolidine group with respect to the quinoxaline system. The dihedral angle between the fused planar rings and the oxazolidin-2-one ring is 41.63 (8)° in the title mol­ecule. PMID:21579110

  18. Tunable-channel multiaccess (TCMA) networks: a new class of high-speed networks suitable for multimedia integrated networking

    NASA Astrophysics Data System (ADS)

    Cheung, Kwok-wai; Chen, Lian-Kuan; Su, C.; Yeung, C. T.; To, P. T.

    1993-11-01

    Tunable-channel multi-access (TCMA) networks are a new class of multi-channel networks that employ local channel tuning to reduce the node complexity. These networks are hybrids of switching networks and multiaccess networks and are vary suitable for high-speed multimedia integrated networking. Various distributed network protocols for these TCMA networks based on star, bus and ring topologies are discussed, including two particularly promising protocols, ACTA and EQEB. Both are based on bus/ring topologies, compatible to ATM, have simple design, high throughput, low delay and a performance that is independent of the round-trip delay. Various multiplexing strategies (space-division, wavelength-division, time-division and subcarrier) employing regenerative and non-regenerative implementations are also discussed.

  19. Trimesic acid dimethyl sulfoxide solvate: space group revision

    PubMed Central

    Bernès, Sylvain; Hernández, Guadalupe; Portillo, Roberto; Gutiérrez, René

    2008-01-01

    The structure of the title solvate, C9H6O6·C2H6OS, was determined 30 years ago [Herbstein, Kapon & Wasserman (1978 ▶). Acta Cryst. B34, 1613–1617], with data collected at room temperature, and refined in the space group P21. The present redetermination, based on high-resolution diffraction data, shows that the actual space group is more likely to be P21/m. The crystal structure contains layers of trimesic acid molecules lying on mirror planes. A mirror plane also passes through the S and O atoms of the solvent molecule. The molecules in each layer are inter­connected through strong O—H⋯O hydrogen bonds, forming a two-dimensional supra­molecular network within each layer. The donor groups are the hydroxyls of the trimesic acid mol­ecules, while the acceptors are the carbonyl or the sulfoxide O atoms. PMID:21202984

  20. Infrared and density functional theory studies of formic acid hydrate clusters in noble gas matrices

    NASA Astrophysics Data System (ADS)

    Ito, Fumiyuki

    2016-08-01

    Infrared absorption spectra of formic acid hydrate clusters (HCOOH)m(H2O)n have been measured in noble gas matrices (Ar and Kr). The concentration dependence of the spectra and the comparison with a previous experimental study on HCOOH(H2O) and HCOOH(H2O)2 [Geoge et al., Spectrochim. Acta, Part A 60 (2004) 3225] led to the identification of large clusters. Density functional theory calculations at the B3LYP-DCP/6-31+G(2d,2p) level were carried out to determine the anharmonic vibrational properties of the clusters, enabling a consistent assignment of the observed vibrational peaks to specific clusters.

  1. Separate binding sites for antimycin and mucidin in the respiratory chain of the bacterium Paracoccus denitrificans and their occurrence in other denitrificans bacteria.

    PubMed Central

    Kucera, I; Hedbávný, R; Dadák, V

    1988-01-01

    By means of the method of fluorimetric titration it has been shown that mucidin does not affect the attachment of antimycin to membranes from anaerobically grown Paracoccus denitrificans. The fluorimetric titration with antimycin can be used in the determination of the amount of the cytochrome bc1 complex in the membrane. In cells inhibited with antimycin, the oxidation of cytochromes c was accompanied by the reduction of cytochrome b; in the presence of mucidin this effect did not take place. The results, which indicated a difference in binding sites, were interpreted in terms of the Q-cycle [Mitchell (1976) J. Theor. Biol. 62, 327-367; Trumpower (1981) Biochim. Biophys. Acta 639, 129-155]. Comparable sensitivity towards antimycin and mucidin was shown by other typical denitrifying bacteria: Pseudomonas stutzeri and Alcaligenes xylosoidans, subspecies denitrificans. PMID:2844159

  2. Redetermination of AgPO(3).

    PubMed

    Terebilenko, Katherina V; Zatovsky, Igor V; Ogorodnyk, Ivan V; Baumer, Vyacheslav N; Slobodyanik, Nikolay S

    2011-01-01

    Single crystals of silver(I) polyphosphate(V), AgPO(3), were prepared via a phospho-ric acid melt method using a solution of Ag(3)PO(4) in H(3)PO(4). In comparison with the previous study based on single-crystal Weissenberg photographs [Jost (1961 ▶). Acta Cryst. 14, 779-784], the results were mainly confirmed, but with much higher precision and with all displacement parameters refined anisotropically. The structure is built up from two types of distorted edge- and corner-sharing [AgO(5)] polyhedra, giving rise to multidirectional ribbons, and from two types of PO(4) tetra-hedra linked into meandering chains (PO(3))(n) spreading parallel to the b axis with a repeat unit of four tetra-hedra. The calculated bond-valence sum value of one of the two Ag(I) ions indicates a significant strain of the structure. PMID:21522230

  3. Cloning and Heterologous Expression of the Grecocycline Biosynthetic Gene Cluster

    PubMed Central

    Bilyk, Oksana; Sekurova, Olga N.; Zotchev, Sergey B.; Luzhetskyy, Andriy

    2016-01-01

    Transformation-associated recombination (TAR) in yeast is a rapid and inexpensive method for cloning and assembly of large DNA fragments, which relies on natural homologous recombination. Two vectors, based on p15a and F-factor replicons that can be maintained in yeast, E. coli and streptomycetes have been constructed. These vectors have been successfully employed for assembly of the grecocycline biosynthetic gene cluster from Streptomyces sp. Acta 1362. Fragments of the cluster were obtained by PCR and transformed together with the “capture” vector into the yeast cells, yielding a construct carrying the entire gene cluster. The obtained construct was heterologously expressed in S. albus J1074, yielding several grecocycline congeners. Grecocyclines have unique structural moieties such as a dissacharide side chain, an additional amino sugar at the C-5 position and a thiol group. Enzymes from this pathway may be used for the derivatization of known active angucyclines in order to improve their desired biological properties. PMID:27410036

  4. Is it jolly SAD?

    PubMed

    Dodson, Eleanor

    2003-11-01

    Examples of phasing macromolecular crystal structures based on single-wavelength anomalous dispersion (SAD) have demonstrated that this approach may have general applications in structural biology. With better data-collection facilities and cryogenic techniques, combined with powerful data-processing, phasing and density-modification programs, the SAD approach may prove simpler than phasing from multi-wavelength (MAD) measurements. It can be performed at any wavelength where anomalous scattering can be observed, in many cases using laboratory X-ray sources. However, there is still a need for accurate data, successful phase improvement and a certain amount of luck. This paper extends the discussion of Jolly SAD in Dauter et al. [Dauter, Z., Dauter, M. & Dodson, E. (2002), Acta Cryst. D58, 494-506]. PMID:14573950

  5. 2,2′-(1,3-Diazinane-1,3-di­yl)diaceto­nitrile: a second monoclinic polymorph

    PubMed Central

    Rivera, Augusto; Maldonado, Mauricio; Ríos-Motta, Jaime; Fejfarová, Karla; Dušek, Michal

    2011-01-01

    A new monoclinic polymorph of the title compound, C8H12N4, in the space group P21/n (Z = 4) is reported. The previously known form was also monoclinic, P21 /c (Z = 4), but the unit-cell parameters and crystal packing were different [Shoja & Saba (1993 ▶). Acta Cryst. C49, 354–355]. The hexa­hydro­pyrimidine ring of the title compound adopts a chair conformation with a diequatorial substitution and with the CH2-C N groups oriented nearly parallel and in the same direction [NC—CH2⋯CH2—CN pseudo torsion angle = −6.27 (18)°]. In the crystal, inter­molecular C—H⋯ N hydrogen bonds connects the mol­ecules into a chain along the b axis. PMID:22065712

  6. Refining a model electron-density map via the Phantom Derivative method.

    PubMed

    Burla, Maria Cristina; Carrozzini, Benedetta; Cascarano, Giovanni Luca; Giacovazzo, Carmelo; Polidori, Giampiero

    2015-09-01

    The Phantom Derivative (PhD) method [Giacovazzo (2015), Acta Cryst. A71, 483-512] has recently been described for ab initio and non-ab initio phasing. It is based on the random generation of structures with the same unit cell and the same space group as the target structure (called ancil structures), which are used to create derivatives devoid of experimental diffraction amplitudes. In this paper, the non-ab initio variant of the method was checked using phase sets obtained by molecular-replacement techniques as a starting point for phase extension and refinement. It has been shown that application of PhD is able to extend and refine phases in a way that is competitive with other electron-density modification techniques. PMID:26327376

  7. A Unique Type 4 Chondrite from the Sahara-Acfer 217

    NASA Astrophysics Data System (ADS)

    Bland, P.; Hutchison, R.; Pillinger, C. T.; Bischoff, A.

    1992-07-01

    therefore is a mixture between chromite, magnetite, and ulvospinel. Variation in the composition of this phase is principally in total Fe and Cr, which vary inversely. No Fe-Ni metal was found and troilite is extremely rare; the only analysis has trace Ni. Ni is undetectable in olivine and is depleted in the sample as a whole and this, together with higher mean Fa-values, would tend to rule out a relationship with CK-chondrites (Kallemeyn et al., 1990). Similarly, whilst the fayalite content in olivine might suggest a high-grade CO chondrite the lack of troilite, kamacite, and taenite and the abundance of Cr-rich spinel would tend to preclude this (McSween, 1976). Acfer 217 is a chondrite that is exceptionally poor in metal and sulfide and rich in oxidised Fe. It appears to be unique. Further work will include an oxygen isotope study to determine any relationship with known groups of meteorites. References: Kallemeyn G. W., Rubin A. E. and Wasson J. T. (1990) Geochim. Cosmochim. Acta 55, 881-892. McSween H. Y. (1976) Geochim. Cosmochim. Acta 41, 477-491. McSween H. Y. (1977) Geochim. Cosmochim. Acta 41, 1843-60. Stoffler D., Keil K. and Scott E.R.D. (1991) Geochim. Cosmochim. Acta 55, 3845-3867.

  8. Exotic Molecules in Space: A Coordinated Astronomical Laboratory and Theoretical Study

    NASA Technical Reports Server (NTRS)

    Stringfellow, Guy (Technical Monitor); Thaddeus, Patrick

    2004-01-01

    The final report covers the two year of a grant which represents a direct continuation of NASA NAG5-4050, with the same title as before. It is dedicated as before to the discovery and characterization of new astrophysical molecules. The four years (two of the original grant plus two years extension) have been extremely productive, yielding many new discoveries of astronomical interest at both radio and optical wavelengths, and the publication or submission of the 49 papers listed below. These articles have appeared or will soon appear in the leading refereed journals of astrophysics, chemical physics, physics, or molecular spectroscopy. One is a major invited review (#27) for Moleculur Physics. One of our other invited reviews published in Spectrochimica Acta in 2001 was recently awarded the Sir Harold Thompson Memorial Award, annually given to the best paper in that journal. Michael McCarthy has recently been awarded the Broida Prize.

  9. The Relationship Between Metal and Silicates in Type I Chondrules

    NASA Astrophysics Data System (ADS)

    Hewins, R. H.; Zanda, B.

    1992-07-01

    ranges could have different metal-silicate ratios. High concentrations of Si, Cr, and P in metal in chondrules have been explained as due to precursor grains of condensation origin (Grossman and Olsen, 1974; Desnoyers, 1980; Zanda, 1992) but might alternatively be due to reduction during melting at very low oxygen fugacities (Dickinson et al., 1992). We find the highest concentrations of Cr and Si in the metal in the chondrules with the highest degree of melting associated with the most magnesian silicates. This suggests that these elements were reduced into the metal during chondrule melting. However, among these forsteritic chondrules, those that experienced higher oxygen fugacities based on Cr partitioning between olivine and metal have metal grains with silica melt droplets instead of reduced Si. This indicates oxidation during cooling at temperatures exceeding 1713 degrees C. Clearly metal, like silicate, was modified during chondrule formation and that probably accounts both for the integration of Cr and Si into metal and the formation of the round silica inclusions observed by Perron et al. (1992). References: McSween H. Jr. (1977) Geochim. Cosmochim. Acta 41, 1843-1860. Zanda B., Bourot-Denise M., and Perron C. (1991) Lunar Planet. Sci. XXII, 1543-1544. Rambaldi E.R. and Wasson J.T. (1981) Geochim. Cosmochim. Acta 45, 1001-1015. Grossman J. and Wasson J.T. (1987) Geochim. Cosmochim. Acta 51, 3003-3011. Grossman L. and Olsen E. (1974) Geochim. Cosmochim. Acta 38, 173- 187. Desnoyer C. (1980) Earth Planet. Sci. Lett. 47, 223-234. Dickinson T.L., Lofgren G.E., and Casanova I. (1992) Lunar Planet. Sci. XXII, 309-310. Perron C., Zanda B., Bourot-Denise M., and Mostefaoui S. (1992) Meteoritics, this volume.

  10. Tetra­methyl 1,1,2-triphenyl-2H-1λ5-phosphole-2,3,4,5-tetra­carboxyl­ate

    PubMed Central

    Krawczyk, Krzysztof K.; Wojtasiewicz, Krystyna; Maurin, Jan K.; Gronowska, Ewa; Czarnocki, Zbigniew

    2010-01-01

    The title compound, C30H27O8P (1), was formed as one of two products {(1) and (2) [Krawczyk et al. (2010 ▶). Acta Cryst. E66 (cv2753)]} in the reaction of dimethyl acetyl­enedicarboxyl­ate with triphenyl­phosphine. The mol­ecule of (1) consists of a five-membered ring, in which the P atom is incorporated. One of the phenyl groups of the triphenyl­phosphine migrated to a vicinal C atom during the reaction. The five-membered ring of (1) is corrugated [r.m.s. deviation = 0.0719 (8) Å], whereas that in compound (2) is planar, the r.m.s. deviation being only 0.009 (2) Å. PMID:21588988

  11. 1,3,5-Tri-p-tolyl­pentane-1,5-diol

    PubMed Central

    Thiruvalluvar, A.; Chithiravel, R.; Muthusubramanian, S.; Butcher, R. J.

    2014-01-01

    In the title compound, C26H30O2, the central benzene ring forms dihedral angles of 14.85 (15) and 28.17 (14)° with the terminal benzene rings. The dihedral angle between the terminal benzene rings is 32.14 (13)°. The crystal packing exhibits two strong inter­molecular O—H⋯O hydrogen bonds, forming directed four-membered co-operative rings. A region of disordered electron density, most probably disordered ethyl acetate solvent mol­ecules, occupying voids of ca 519 Å3 for an electron count of 59, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148–155]. Their formula mass and unit-cell characteristics were not taken into account during refinement. The structure was refined as an inversion twin [absolute structure parameter = −0.3 (4)]. PMID:24764851

  12. Terrestrial microbes in martian and chondritic meteorites

    NASA Astrophysics Data System (ADS)

    Airieau, S.; Piceno, Y.; Andersen, G.

    2007-08-01

    Good extraterrestrial analogs for microbiology are SNC meteorites as Mars analogs, and chondrites as early planet analogs. Chondrites and SNCs are used to trace processes in the early solar system and on Mars. Yet, questions about terrestrial contamination and its effects on the isotopic, chemical and mineral characteristics often arise. A wide biodiversity was found in 21 chondrites of groups CR, CV, CK, CO from ANSMET, CI and CM Falls, and 8 SNCs. Studies documented the alteration of meteorites by weathering and biology [1]-[6], and during aqueous extraction for oxygen isotopic analysis [7], visible biofilms grew in the meteorite solutions in days. To assess biological isotopic and chemical impacts, cultures were incubated 11 months and analyzed by PCR. The sequences for 2 isolates from EET 87770 and Leoville were of a good quality with long sequence reads. In EET 87770, the closest matches were in the genus Microbacterium. Soil and plant isolates were close relatives by sequence comparison. Bacillus, a common soil bacterial genus, grew in a Leoville culture. All SNCs exhibited biological activity measured independently by LAL but only 1 colony was successfully cultured from grains of the SNC Los Angeles. Isotopic analyses of samples with various amounts of microbial contamination could help quantified isotopic impact of microbes on protoplanetary chemistry in these rocks. References: [1] Gounelle, M.& Zolensky M. (2001) LPS XXXII, Abstract #999. [2] Fries, M. et al. (2005) Meteoritical Society Meeting 68, Abstract # 5201. [3] Burckle, L. H. & Delaney, J. S (1999) Meteoritics & Planet. Sci., 32, 475. [4] Whitby, C. et al. (2000) LPS XXXI, Abstract #1732. [5] Tyra M. et al., (2007) Geochim. Cosmochim. Acta, 71, 782 [6] Toporski, J. & Steele A., (2007) Astrobiology, 7, 389 [7]Airieau, S. et al (2005) Geochim. Cosmochim. Acta, 69, 4166.

  13. A new ground-level fallout record of uranium and plutonium isotopes for northern temperate latitudes

    NASA Astrophysics Data System (ADS)

    Warneke, Thorsten; Croudace, Ian W.; Warwick, Phillip E.; Taylor, Rex N.

    2002-11-01

    Plutonium and uranium isotope ratios can be used to differentiate the sources of nuclear contamination from nuclear weapon establishments (Environ. Sci. Technol. 34 (2000) 4496; Internal Report for AWRE Aldermaston, UK (1961)), weapon fallout (Geochim. Cosmochim. Acta 51 (1987) 2623; Earth Planet. Sci. Lett. 63 (1983) 202; Earth Planet. Sci. Lett. 22 (1974) 111; Geochim. Cosmochim. Acta 64 (2000) 989), reprocessing plants, reactor or satellite accidents (Science 105 (1979) 583; Science 238 (1987) 512) and in addition they provide markers for post-1952 geochronology of environmental systems. A good record of plutonium and uranium isotope ratios of the background resulting from atmospheric nuclear testing is essential for source characterisation studies. Using recently developed mass spectrometric techniques (J. Anal. At. Spectrom. 16 (2001) 279) we present here the first complete records between 1952 and the present day of northern temperate latitude 240Pu/ 239Pu and 238U/ 235U atom ratios for atmospheric deposition. Such information was not derived directly during the period of atmospheric testing because suitable mass spectrometric capability was not available. The currently derived records are based on an annual herbage archive and a core from an Alpine glacier. These studies reveal hitherto unseen fluctuations in the 238U/ 235U atmospheric fallout record, some of which are directly related to nuclear testing. In addition, they also provide the first evidence that plutonium contamination originating from Nevada Desert atmospheric weapon tests in 1952 and 1953 extended eastwards as far as northwestern Europe. The results presented here demonstrate that we now have the capability to detect and precisely identify sources of plutonium in the environment with implications for the development of atmospheric transport models, recent geochronology and environmental studies.

  14. Digital diagnosis of medical images

    NASA Astrophysics Data System (ADS)

    Heinonen, Tomi; Kuismin, Raimo; Jormalainen, Raimo; Dastidar, Prasun; Frey, Harry; Eskola, Hannu

    2001-08-01

    The popularity of digital imaging devices and PACS installations has increased during the last years. Still, images are analyzed and diagnosed using conventional techniques. Our research group begun to study the requirements for digital image diagnostic methods to be applied together with PACS systems. The research was focused on various image analysis procedures (e.g., segmentation, volumetry, 3D visualization, image fusion, anatomic atlas, etc.) that could be useful in medical diagnosis. We have developed Image Analysis software (www.medimag.net) to enable several image-processing applications in medical diagnosis, such as volumetry, multimodal visualization, and 3D visualizations. We have also developed a commercial scalable image archive system (ActaServer, supports DICOM) based on component technology (www.acta.fi), and several telemedicine applications. All the software and systems operate in NT environment and are in clinical use in several hospitals. The analysis software have been applied in clinical work and utilized in numerous patient cases (500 patients). This method has been used in the diagnosis, therapy and follow-up in various diseases of the central nervous system (CNS), respiratory system (RS) and human reproductive system (HRS). In many of these diseases e.g. Systemic Lupus Erythematosus (CNS), nasal airways diseases (RS) and ovarian tumors (HRS), these methods have been used for the first time in clinical work. According to our results, digital diagnosis improves diagnostic capabilities, and together with PACS installations it will become standard tool during the next decade by enabling more accurate diagnosis and patient follow-up.

  15. Developmental pathways and endothelial to mesenchymal transition in canine myxomatous mitral valve disease.

    PubMed

    Lu, Chi-Chien; Liu, Meng-Meng; Clinton, Michael; Culshaw, Geoff; Argyle, David J; Corcoran, Brendan M

    2015-12-01

    Epithelial to mesenchymal transition (EMT) and the cardiovascular equivalent, endothelial to mesenchymal transition (EndoMT), contribute to a range of chronic degenerative diseases and cancer metastasis. Chronic valvulopathies exhibit some features of EndoMT and activation of developmental signalling pathways, such as osteogenesis and chondrogenesis, expression of cell differentiation markers, basement membrane damage and endothelial transformation. The aim of the present study was to investigate the potential role of developmental mechanisms in canine myxomatous mitral valve disease (MMVD) using a combination of transcriptomic array technology, RT-PCR and immunohistochemistry. There was significant differential expression for genes typically associated with valvulogenesis and EndoMT, including markers of inflammation (IL6, IL18 and TLR4), basement membrane disarray (NID1, LAMA2 and CTSS), mesenchymal and endothelial cell differentiation (MYH11 and TAGLN) and EndoMT (ACTA2, SNAI1, CTNNB1, HAS2, CDH5, and NOTCH1), with fold changes from +15.35 (ACTA2) to -5.52 (LAMA2). These changes in gene expression were confirmed using RT-PCR, except for HAS2. In silico analysis identified important gene networks and canonical pathways in MMVD that have associations with development and organogenesis, including inflammation, valve morphogenesis and EMT, as well as components of the basement membrane and extra-cellular matrix. Immunohistochemistry identified changes in the expression of hyaluronic acid synthase (Has2), Snai1, α-smooth muscle actin (α-SMA) and VE-cadherin (CDH5), and co-expression of Has2 with α-SMA. These research findings strongly suggest involvement of developmental signalling pathways and mechanisms, including EndoMT, in the pathogenesis of canine MMVD. PMID:26586213

  16. Membrane-bound states of alpha-lactalbumin: implications for the protein stability and conformation.

    PubMed Central

    Cawthern, K. M.; Permyakov, E.; Berliner, L. J.

    1996-01-01

    alpha-Lactalbumin (alpha-LA) associates with dimyristoylphosphatidylcholine (DMPC) or egg lecithin (EPC) liposomes. Thermal denaturation of isolated DMPC or EPC alpha-LA complexes was dependent on the metal bound state of the protein. The intrinsic fluorescence of thermally denatured DMPC-alpha-LA was sensitive to two thermal transitions: the Tc of the lipid vesicles, and the denaturation of the protein. Quenching experiments suggested that tryptophan accessibility increased upon protein-DMPC association, in contrast with earlier suggestions that the limited emission red shift upon association with the liposome was due to partial insertion of tryptophan into the apolar phase of the bilayer (Hanssens I et al., 1985, Biochim Biophys Acta 817:154-166). On the other hand, above the protein transition (70 degrees C), the spectral blue shifts and reduced accessibility to quencher suggested that tryptophan interacts significantly with the apolar phase of either DMPC and EPC. At pH 2, where the protein inserts into the bilayer rapidly, the isolated DMPC-alpha-LA complex showed a distinct fluorescence thermal transition between 40 and 60 degrees C, consistent with a partially inserted form that possesses some degree of tertiary structure and unfolds cooperatively. This result is significant in light of earlier findings of increased helicity for the acid form, i.e., molten globule state of the protein (Hanssens I et al., 1985, Biochim Biophys Acta 817:154-166). These results suggest a model where a limited expansion of conformation occurs upon association with the membrane at neutral pH and physiological temperatures, with a concomitant increase in the exposure of tryptophan to external quenchers; i.e., the current data do not support a model where an apolar, tryptophan-containing surface is covered by the lipid phase of the bilayer. PMID:8819172

  17. Crystal structure of bis-p-anizidinegossypol with an unknown solvate.

    PubMed

    Honkeldieva, Muhabbat T; Talipov, Samat A; Kunafiev, Rishad; Ibragimov, Bakhtiyar T

    2015-12-01

    The title compound, C44H44N2O8, (systematic name: 1,1',6,6'-tetra-hydroxy-5,5'-diisopropyl-8,8'-bis-{[(4-meth-oxy-phen-yl)iminium-yl]meth-yl}-3,3'-dimethyl-2,2'-bi-naphthalene-7,7'-diolate) has been obtained by the addition of p-anizidine to gossypol dissolved in di-chloro-methane. In the solid state, the title compound exists in the enamine or quinoid form. The two naphthyl moieties are inclined to one another by 72.08 (5)°. The pendant phenyl rings are inclined at 22.26 (14) and 23.86 (13)° to the corresponding naphthyl rings. In the crystal, mol-ecules are incorporated into layers through inversion-related pairs of O-H⋯O inter-actions [graph sets R 2 (2)(20) and R 2 (2)(10)] and translation-related O-H⋯O inter-actions [graph set C(15)]. The packing of these layers in the crystal structure gives rise to channels in the [011] direction, with hydro-phobic inter-actions occurring between adjacent layers. The channels are 5-7 Å wide, and the void volume of each cell is 655 Å(3), corresponding to 26.6% of the cell volume. Disordered guest mol-ecules, probably solvent and water mol-ecules, occupy these voids of the crystal; their contribution to the scattering was removed with the SQUEEZE routine [Spek (2015 ▸). Acta Cryst. C71, 9-18] of PLATON [Spek (2009 ▸). Acta Cryst. D65, 148-155]. PMID:26870395

  18. FGFR2IIIb-MAPK Activity Is Required for Epithelial Cell Fate Decision in the Lower Müllerian Duct.

    PubMed

    Terakawa, Jumpei; Rocchi, Altea; Serna, Vanida A; Bottinger, Erwin P; Graff, Jonathan M; Kurita, Takeshi

    2016-07-01

    Cell fate of lower Müllerian duct epithelium (MDE), to become uterine or vaginal epithelium, is determined by the absence or presence of ΔNp63 expression, respectively. Previously, we showed that SMAD4 and runt-related transcription factor 1 (RUNX1) were independently required for MDE to express ΔNp63. Here, we report that vaginal mesenchyme directs vaginal epithelial cell fate in MDE through paracrine activation of fibroblast growth factor (FGF) receptor-MAPK pathway. In the developing reproductive tract, FGF7 and FGF10 were enriched in vaginal mesenchyme, whereas FGF receptor 2IIIb was expressed in epithelia of both the uterus and vagina. When Fgfr2 was inactivated, vaginal MDE underwent uterine cell fate, and this differentiation defect was corrected by activation of MEK-ERK pathway. In vitro, FGF10 in combination with bone morphogenetic protein 4 and activin A (ActA) was sufficient to induce ΔNp63 in MDE, and ActA was essential for induction of RUNX1 through SMAD-independent pathways. Accordingly, inhibition of type 1 receptors for activin in neonatal mice induced uterine differentiation in vaginal epithelium by down-regulating RUNX1, whereas conditional deletion of Smad2 and Smad3 had no effect on vaginal epithelial differentiation. In conclusion, vaginal epithelial cell fate in MDE is induced by FGF7/10-MAPK, bone morphogenetic protein 4-SMAD, and ActA-RUNX1 pathway activities, and the disruption in any one of these pathways results in conversion from vaginal to uterine epithelial cell fate. PMID:27164167

  19. Prediction of the thermodynamic properties of metal-arsenate and metal-arsenite aqueous complexes to high temperatures and pressures and some geological consequences

    NASA Astrophysics Data System (ADS)

    Marini, Luigi; Accornero, Marina

    2007-07-01

    The standard thermodynamic properties at 25°C, 1 bar (Δ G {f/o}, Δ H {f/o}, S o, C {P/o}, V o, ω) and the coefficients of the revised Helgeson-Kirkham-Flowers equations of state were evaluated for several aqueous complexes formed by dissolved metals and either arsenate or arsenite ions. The guidelines of Shock and Helgeson (Geochim Cosmochim Acta 52:2009-2036, 1988) and Sverjensky et al. (Geochim Cosmochim Acta 61:1359-1412, 1997) were followed and corroborated with alternative approaches, whenever possible. The SUPCRT92 computer code was used to generate the log K of the destruction reactions of these metal-arsenate and metal-arsenite aqueous complexes at pressures and temperatures required by the EQ3/6 software package, version 7.2b. Apart from the AlAsO{4/o} and FeAsO{4/o} complexes, our log K at 25°C, 1 bar are in fair agreement with those of Whiting (MS Thesis, Colorado School of Mines, Golden, CO, 1992). Moreover, the equilibrium constants evaluated in this study are in good to fair agreement with those determined experimentally for the Ca-dihydroarsenate and Ca-hydroarsenate complexes at 40°C (Mironov et al., Russ J Inorg Chem 40:1690, 1995) and for Fe(III)-hydroarsenate complex at 25°C (Raposo et al., J Sol Chem 35:79-94, 2006), whereas the disagreement with the log K measured for the Ca-arsenate complex at 40°C (Mironov et al., Russ J Inorg Chem 40:1690, 1995) might be due to uncertainties in this measured value. The implications of aqueous complexing between dissolved metals and arsenate/arsenite ions were investigated for seawater, high-temperature geothermal liquids and acid mine drainage and aqueous solutions deriving from mixing of acid mine waters and surface waters.

  20. Autophagy fosters myofibroblast differentiation through MTORC2 activation and downstream upregulation of CTGF.

    PubMed

    Bernard, Monique; Dieudé, Mélanie; Yang, Bing; Hamelin, Katia; Underwood, Katy; Hébert, Marie-Josée

    2014-01-01

    Recent evidence suggests that autophagy may favor fibrosis through enhanced differentiation of fibroblasts in myofibroblasts. Here, we sought to characterize the mediators and signaling pathways implicated in autophagy-induced myofibroblast differentiation. Fibroblasts, serum starved for up to 4 d, showed increased LC3-II/-I ratios and decreased SQSTM1/p62 levels. Autophagy was associated with acquisition of markers of myofibroblast differentiation including increased protein levels of ACTA2/αSMA (actin, α 2, smooth muscle, aorta), enhanced gene and protein levels of COL1A1 (collagen, type I, α 1) and COL3A1, and the formation of stress fibers. Inhibiting autophagy with 3 different class I phosphoinositide 3-kinase and class III phosphatidylinositol 3-kinase (PtdIns3K) inhibitors or through ATG7 silencing prevented myofibroblast differentiation. Autophagic fibroblasts showed increased expression and secretion of CTGF (connective tissue growth factor), and CTGF silencing prevented myofibroblast differentiation. Phosphorylation of the MTORC1 target RPS6KB1/p70S6K kinase was abolished in starved fibroblasts. Phosphorylation of AKT at Ser473, a MTORC2 target, was reduced after initiation of starvation but was followed by spontaneous rephosphorylation after 2 d of starvation, suggesting the reactivation of MTORC2 with sustained autophagy. Inhibiting MTORC2 activation with long-term exposure to rapamycin or by silencing RICTOR, a central component of the MTORC2 complex abolished AKT rephosphorylation. Both RICTOR silencing and rapamycin treatment prevented CTGF and ACTA2 upregulation, demonstrating the central role of MTORC2 activation in CTGF induction and myofibroblast differentiation. Finally, inhibition of autophagy with PtdIns3K inhibitors or ATG7 silencing blocked AKT rephosphorylation. Collectively, these results identify autophagy as a novel activator of MTORC2 signaling leading to CTGF induction and myofibroblast differentiation. PMID:25495560