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  1. Dépistage des maladies cardiovasculaires chez des étudiants de l'Université de Douala et influence des activités physiques et sportives

    PubMed Central

    Ewane, Marielle Epacka; Mandengue, Samuel Honoré; Priso, Eugene Belle; Tamba, Stéphane Moumbe; Ahmadou; Fouda, André Bita

    2012-01-01

    Introduction Les maladies cardiovasculaires (MCV) constituent l'une des principales causes de mortalité dans les pays en développement. Le dépistage de ces dernières chez des jeunes est un défi dans la lutte contre leur expansion. Le but de cette étude était de dépister ces maladies au sein d'une population jeunes d’étudiants camerounais. Methodes Deux mille six cent cinquante-huit étudiants de l'Université de Douala (23,6 ± 2,9 ans, sex-ratio H/F = 0,9) ont en Avril - Mai 2011 participé à une campagne de dépistage gratuit du diabète, de l'hypertension artérielle (HTA) et de l'obésité. Ils ont également été soumis à une d'enquête évaluant leur niveau en activités physiques et sportives (APS). Resultats 12,7% des participants avaient une pression artérielle (PA) ≥ 140/90 mmHg, 3,6% étaient obèses et 0,9% avaient une glycémie ≥1,26 g/L. Des corrélations ont été trouvées entre certains facteurs de risque (diabète, hypertension et obésité) et le niveau académique d'une part (r =0,366; p < 0,0001) et le temps passé devant la télévision d'autres part (r = 0,411; p < 0,0001). L‘APS était inversement corrélée à l‘âge (r =-0,015; p < 0,0001) et au temps passé devant la télévision (r = -0,059; p = 0,002). Conclusion La présence des MCV et leurs facteurs de risque mis en évidence dans cette étude réalisée en milieu estudiantin camerounais interpelle à une prévention et une éducation dans la lutte contre ces dernières. PMID:22655111

  2. Overview of Outreach Activities of the Planetary Sciences and Remote Sensing Group at Freie Universität Berlin

    NASA Astrophysics Data System (ADS)

    Musiol, S.; Balthasar, H.; Dumke, A.; Gross, C.; Michael, G.; Neu, D.; Platz, T.; Rosenberg, H.; Schreiner, B.; Walter, S. H. G.; van Gasselt, S.

    2014-04-01

    Planetary Sciences teach us how special our homeplanet is in the solar system. Incorporating a broad variety of natural science topics they count to the most fundamental branches of scientific research with a strong interdisciplinary character. However, since planetary sciences are not a school subject, children as well as adults are often lacking an overall awareness and understanding of that field. The mission of planetary education has to be fulfilled by research institutions. With several platforms and activities our group is engaged to address this topic. The Planetary Sciences and Remote Sensing Group at Freie Universität Berlin (FUB) is involved in space missions such as Mars Express with the High Resolution Stereo Camera (HRSC), Cassini to Saturn, and Dawn to the asteroids Vesta and Ceres. Moreover, we participate in developing a planetary X-ray fluorescence spectrometer. Information of our planetary research activities can be found on our institutes website [1]. Our outreach activities include press releases, an image download hub, permanent and special exhibition support, 3D-HD-animation production, science fairs, workshops, hands-on courses, public talks at observatories and schools, as well as media appearances in radio, press and TV.

  3. The DES Science Verification Weak Lensing Shear Catalogues

    NASA Astrophysics Data System (ADS)

    Jarvis, M.; Sheldon, E.; Zuntz, J.; Kacprzak, T.; Bridle, S. L.; Amara, A.; Armstrong, R.; Becker, M. R.; Bernstein, G. M.; Bonnett, C.; Chang, C.; Das, R.; Dietrich, J. P.; Drlica-Wagner, A.; Eifler, T. F.; Gangkofner, C.; Gruen, D.; Hirsch, M.; Huff, E. M.; Jain, B.; Kent, S.; Kirk, D.; MacCrann, N.; Melchior, P.; Plazas, A. A.; Refregier, A.; Rowe, B.; Rykoff, E. S.; Samuroff, S.; Sánchez, C.; Suchyta, E.; Troxel, M. A.; Vikram, V.; Abbott, T.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Rosell, A. Carnero; Kind, M. Carrasco; Carretero, J.; Castander, F. J.; Clampitt, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Neto, A. Fausti; Flaugher, B.; Fosalba, P.; Frieman, J.; Gaztanaga, E.; Gerdes, D. W.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; March, M.; Martini, P.; Miquel, R.; Mohr, J. J.; Neilsen, E.; Nord, B.; Ogando, R.; Reil, K.; Romer, A. K.; Roodman, A.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Walker, A. R.; Wechsler, R. H.

    2016-05-01

    We present weak lensing shear catalogues for 139 square degrees of data taken during the Science Verification (SV) time for the new Dark Energy Camera (DECam) being used for the Dark Energy Survey (DES). We describe our object selection, point spread function estimation and shear measurement procedures using two independent shear pipelines, IM3SHAPE and NGMIX, which produce catalogues of 2.12 million and 3.44 million galaxies respectively. We detail a set of null tests for the shear measurements and find that they pass the requirements for systematic errors at the level necessary for weak lensing science applications using the SV data. We also discuss some of the planned algorithmic improvements that will be necessary to produce sufficiently accurate shear catalogues for the full 5-year DES, which is expected to cover 5000 square degrees.

  4. The DES Science Verification Weak Lensing Shear Catalogs

    SciTech Connect

    Jarvis, M.

    2015-07-20

    We present weak lensing shear catalogs for 139 square degrees of data taken during the Science Verification (SV) time for the new Dark Energy Camera (DECam) being used for the Dark Energy Survey (DES). We describe our object selection, point spread function estimation and shear measurement procedures using two independent shear pipelines, IM3SHAPE and NGMIX, which produce catalogs of 2.12 million and 3.44 million galaxies respectively. We also detail a set of null tests for the shear measurements and find that they pass the requirements for systematic errors at the level necessary for weak lensing science applications using the SV data. Furthermore, we discuss some of the planned algorithmic improvements that will be necessary to produce sufficiently accurate shear catalogs for the full 5-year DES, which is expected to cover 5000 square degrees.

  5. CMB lensing tomography with the DES Science Verification galaxies

    NASA Astrophysics Data System (ADS)

    Giannantonio, T.; Fosalba, P.; Cawthon, R.; Omori, Y.; Crocce, M.; Elsner, F.; Leistedt, B.; Dodelson, S.; Benoit-Lévy, A.; Gaztañaga, E.; Holder, G.; Peiris, H. V.; Percival, W. J.; Kirk, D.; Bauer, A. H.; Benson, B. A.; Bernstein, G. M.; Carretero, J.; Crawford, T. M.; Crittenden, R.; Huterer, D.; Jain, B.; Krause, E.; Reichardt, C. L.; Ross, A. J.; Simard, G.; Soergel, B.; Stark, A.; Story, K. T.; Vieira, J. D.; Weller, J.; Abbott, T.; Abdalla, F. B.; Allam, S.; Armstrong, R.; Banerji, M.; Bernstein, R. A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carlstrom, J. E.; Carnero Rosell, A.; Carrasco Kind, M.; Castander, F. J.; Chang, C. L.; Cunha, C. E.; da Costa, L. N.; D'Andrea, C. B.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Evrard, A. E.; Neto, A. Fausti; Fernandez, E.; Finley, D. A.; Flaugher, B.; Frieman, J.; Gerdes, D.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Holzapfel, W. L.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; March, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Romer, A. K.; Roodman, A.; Rykoff, E. S.; Sako, M.; Saliwanchik, B. R.; Sanchez, E.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Vikram, V.; Walker, A. R.; Wechsler, R. H.; Zuntz, J.

    2016-03-01

    We measure the cross-correlation between the galaxy density in the Dark Energy Survey (DES) Science Verification data and the lensing of the cosmic microwave background (CMB) as reconstructed with the Planck satellite and the South Pole Telescope (SPT). When using the DES main galaxy sample over the full redshift range 0.2 < zphot < 1.2, a cross-correlation signal is detected at 6σ and 4σ with SPT and Planck , respectively. We then divide the DES galaxies into five photometric redshift bins, finding significant (>2σ) detections in all bins. Comparing to the fiducial Planck cosmology, we find the redshift evolution of the signal matches expectations, although the amplitude is consistently lower than predicted across redshift bins. We test for possible systematics that could affect our result and find no evidence for significant contamination. Finally, we demonstrate how these measurements can be used to constrain the growth of structure across cosmic time. We find the data are fit by a model in which the amplitude of structure in the z < 1.2 universe is 0.73 ± 0.16 times as large as predicted in the Λ cold dark matter Planck cosmology, a 1.7σ deviation.

  6. CMB lensing tomography with the DES Science Verification galaxies

    DOE PAGESBeta

    Giannantonio, T.

    2016-01-07

    We measure the cross-correlation between the galaxy density in the Dark Energy Survey (DES) Science Verification data and the lensing of the cosmic microwave background (CMB) as reconstructed with the Planck satellite and the South Pole Telescope (SPT). When using the DES main galaxy sample over the full redshift range 0.2 < zphot < 1.2, a cross-correlation signal is detected at 6σ and 4σ with SPT and Planck respectively. We then divide the DES galaxies into five photometric redshift bins, finding significant (>2σ) detections in all bins. Comparing to the fiducial Planck cosmology, we find the redshift evolution of themore » signal matches expectations, although the amplitude is consistently lower than predicted across redshift bins. We test for possible systematics that could affect our result and find no evidence for significant contamination. Finally, we demonstrate how these measurements can be used to constrain the growth of structure across cosmic time. We find the data are fit by a model in which the amplitude of structure in the z < 1.2 universe is 0.73 ± 0.16 times as large as predicted in the LCDM Planck cosmology, a 1.7σ deviation.« less

  7. Cosmology from Cosmic Shear with DES Science Verification Data

    SciTech Connect

    Abbott, T.

    2015-07-20

    We present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find σ8(m=0.3)0.5 = 0:81 ± 0:06 (68% confidence), after marginalising over 7 systematics parameters and 3 other cosmological parameters. Furthermore, we examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About 20% of our error bar comes from marginalising over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data. Our results are consistent with both datasets. Our uncertainties are ~30% larger than those from CFHTLenS when we carry out a comparable analysis of the two datasets, which we attribute largely to the lower number density of our shear catalogue. We investigate constraints on dark energy and find that, with this small fraction of the full survey, the DES SV constraints make negligible impact on the Planck constraints. The moderate disagreement between the CFHTLenS and Planck values of σ8m=0.3)0.5 is present regardless of the value of w.

  8. Cosmic Shear Measurements with DES Science Verification Data

    SciTech Connect

    Becker, M. R.

    2015-07-20

    We present measurements of weak gravitational lensing cosmic shear two-point statistics using Dark Energy Survey Science Verification data. We demonstrate that our results are robust to the choice of shear measurement pipeline, either ngmix or im3shape, and robust to the choice of two-point statistic, including both real and Fourier-space statistics. Our results pass a suite of null tests including tests for B-mode contamination and direct tests for any dependence of the two-point functions on a set of 16 observing conditions and galaxy properties, such as seeing, airmass, galaxy color, galaxy magnitude, etc. We use a large suite of simulations to compute the covariance matrix of the cosmic shear measurements and assign statistical significance to our null tests. We find that our covariance matrix is consistent with the halo model prediction, indicating that it has the appropriate level of halo sample variance. We also compare the same jackknife procedure applied to the data and the simulations in order to search for additional sources of noise not captured by the simulations. We find no statistically significant extra sources of noise in the data. The overall detection significance with tomography for our highest source density catalog is 9.7σ. Cosmological constraints from the measurements in this work are presented in a companion paper (DES et al. 2015).

  9. Caractérisation électrique des interfaces P^+ - Si - poly/N-c-Si réalisées par dépôt LPCVD de films fortement dopés in situ au bore

    NASA Astrophysics Data System (ADS)

    Akani, M.; Benouis, C. E.; Benzohra, M.

    1993-11-01

    La liste des auteurs (et leur adresse) concernant cet article sont à corriger comme suit: The list of authors (and the address) for this article are to be corrected as follows: M. Idrissi-Benzohra, M. Akani, C. E. Benouis, M. Benzohra Laboratoire d'Analyse des Composants au Silcium, Université des Sciences et de la Technologie d'Oran, Oran El-Mnaouer 31000, Algérie.

  10. Integration des sciences et de la langue: Creation et experimentation d'un modele pedagogique pour ameliorer l'apprentissage des sciences en milieu francophone minoritaire

    NASA Astrophysics Data System (ADS)

    Cormier, Marianne

    Les faibles resultats en sciences des eleves du milieu francophone minoritaire, lors d'epreuves au plan national et international, ont interpelle la recherche de solutions. Cette these avait pour but de creer et d'experimenter un modele pedagogique pour l'enseignement des sciences en milieu linguistique minoritaire. En raison de la presence de divers degres de francite chez la clientele scolaire de ce milieu, plusieurs elements langagiers (l'ecriture, la discussion et la lecture) ont ete integres a l'apprentissage scientifique. Nous avions recommande de commencer le processus d'apprentissage avec des elements langagiers plutot informels (redaction dans un journal, discussions en dyades...) pour progresser vers des activites langagieres plus formelles (redaction de rapports ou d'explications scientifiques). En ce qui a trait a l'apprentissage scientifique, le modele preconisait une demarche d'evolution conceptuelle d'inspiration socio-constructiviste tout en s'appuyant fortement sur l'apprentissage experientiel. Lors de l'experimentation du modele, nous voulions savoir si celui-ci provoquait une evolution conceptuelle chez les eleves, et si, simultanement, le vocabulaire scientifique de ces derniers s'enrichissait. Par ailleurs, nous cherchions a comprendre comment les eleves vivaient leurs apprentissages dans le cadre de ce modele pedagogique. Une classe de cinquieme annee de l'ecole de Grande-Digue, dans le Sud-est du Nouveau-Brunswick, a participe a la mise a l'essai du modele en etudiant les marais sales locaux. Lors d'entrevues initiales, nous avons remarque que les connaissances des eleves au sujet des marais sales etaient limitees. En effet, s'ils etaient conscients que les marais etaient des lieux naturels, ils ne pouvaient pas necessairement les decrire avec precision. Nous avons egalement constate que les eleves utilisaient surtout des mots communs (plantes, oiseaux, insectes) pour decrire le marais. Les resultats obtenus indiquent que les eleves ont progresse dans leurs conceptions au sujet des marais. A la suite de l'intervention pedagogique, ils peuvent decrire le marais de facon comparable a des scientifiques en mettant a profit des mots scientifiques (spartine alterniflore, detritus, chevalier a pattes jaunes). Selon nous, les apprentissages des eleves s'expliquent surtout par la juxtaposition, dans le modele pedagogique, des elements langagiers avec une demarche de changement conceptuel a caractere experientiel. En effet, lors de cette demarche, les eleves se sont beaucoup questionnes, ont ecrit leurs reflexions, discute de leurs preoccupations et consulte des documents. Ces activites langagieres se sont deroulees directement dans le marais ainsi qu'a la suite de visites dans celui-ci. Ainsi, la possibilite de decouverte a ete reelle pour eux. Ces differents elements se sont combines pour creer une forte motivation. Le tout s'est arrime pour permettre une evolution conceptuelle et langagiere. Le modele pedagogique experimente pourrait ainsi s'averer tres fecond aupres des eleves du milieu linguistique minoritaire.

  11. Science, Pedagogie et Art: Des Ressemblances et des Differences (Science, Pedagogy, and Art: The Similarities and Differences).

    ERIC Educational Resources Information Center

    Gauthier, Clermont

    1991-01-01

    Compares science, pedagogy, and art in terms of scope, purpose, rhetoric, effects, discourse, and other factors. Views science as positivistically oriented toward reality, art as producing unpredictable effects, and pedagogy as focused on students. Concludes that pedagogy is neither science nor art but rather an exercise in persuasion. (PAA)

  12. University Observatory, Ludwig-Maximilians-Universität

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The University Observatory of Ludwig-Maximilians-Universität was founded in 1816. Astronomers who worked or graduated at the Munich Observatory include: Fraunhofer, Soldner, Lamont, Seeliger and Karl Schwarzschild. At present four professors and ten staff astronomers work here. Funding comes from the Bavarian Government, the German Science Foundation, and other German and European research progra...

  13. The Photometric Calibration of the Dark Energy Survey (DES): Results from the Summer 2013 Re-processing of the DES Science Verification Data

    NASA Astrophysics Data System (ADS)

    Tucker, Douglas L.; Allam, S. S.; Annis, J. T.; Armstrong, R.; Bauer, A.; Bernstein, G.; Burke, D.; Fix, M.; Foust, W.; Gruendl, R. A.; Head, H.; Kuehn, K.; Kuhlmann, S.; Li, T.; Lin, H.; Rykoff, E. S.; Smith, J.; Wester, W.; Wyatt, S.; Yanny, B.; Energy Survey, Dark

    2014-01-01

    The Dark Energy Survey (DES) -- a five-year 5000 sq deg grizY survey of the Southern sky to probe the parameters of dark energy -- recently began operations using the new 3 sq deg DECam imager on the Blanco 4m telescope at the Cerro Tololo Interamerican Observatory. In order to achieve its science goals, the DES has tight requirements on both its relative and absolute photometric calibrations. The 5-year requirements are (1) an internal (relative) photometric calibration of 2% rms (2) an absolute color calibration of 0.5%, and (3) an absolute flux calibration of 0.5% (in i-band relative to BD+17 4708). In preparation for DES operations, the instrument+telescope underwent a period of Science Verification between November 2012 and February 2013. These Science Verification (SV) data were quickly processed to determine whether the image data were being produced with sufficient quality and efficiency to meet DES science goals. These data were also useful for initial science, and they were re-processed and re-calibrated during Summer 2013. The photometric goals for Summer 2013 re-processing of the DES SV were intentionally more relaxed than the requirements for the final 5-year survey: (1) an all-sky internal (relative) calibration goal of 3%, (2) an absolute color goal of 3%, and (3) an absolute flux goal of 3%. Here, we describe the results from the photometric calibration of the Summer 2013 re-processing of the DES SV data, the lessons learned, and plans for the future.

  14. Quebec Science Education: Which Directions? Proceedings of a Symposium Sponsored by the Science Council of Canada and the Association des Professeurs de Sciences du Quebec (March 1982). P82/2.

    ERIC Educational Resources Information Center

    Souque, Jean-Pascal, Ed.; Dufour, Paul, Ed.

    Proceedings are presented of a symposium on science education in Quebec, which was sponsored by the Science Council of Canada and the Association des Professeurs de Sciences du Quebec. Papers and authors addressing the background and present state of Quebec science education are as follows: "Science Teaching at the Secondary Level: An Evaluation"…

  15. Redshift Distributions of Galaxies in the DES Science Verification Shear Catalogue and Implications for Weak Lensing

    SciTech Connect

    Bonnett, C.

    2015-07-21

    We present photometric redshift estimates for galaxies used in the weak lensing analysis of the Dark Energy Survey Science Verification (DES SV) data. Four model- or machine learning-based photometric redshift methods { annz2, bpz calibrated against BCC-U fig simulations, skynet, and tpz { are analysed. For training, calibration, and testing of these methods, we also construct a catalogue of spectroscopically confirmed galaxies matched against DES SV data. The performance of the methods is evalu-ated against the matched spectroscopic catalogue, focusing on metrics relevant for weak lensing analyses, with additional validation against COSMOS photo-zs. From the galaxies in the DES SV shear catalogue, which have mean redshift 0.72 ±0.01 over the range 0:3 < z < 1:3, we construct three tomographic bins with means of z = {0.45; 0.67,1.00g}. These bins each have systematic uncertainties δz ≲ 0.05 in the mean of the fiducial skynet photo-z n(z). We propagate the errors in the redshift distributions through to their impact on cosmological parameters estimated with cosmic shear, and find that they cause shifts in the value of σ8 of approx. 3%. This shift is within the one sigma statistical errors on σ8 for the DES SV shear catalog. We also found that further study of the potential impact of systematic differences on the critical surface density, Σcrit, contained levels of bias safely less than the statistical power of DES SV data. We recommend a final Gaussian prior for the photo-z bias in the mean of n(z) of width 0:05 for each of the three tomographic bins, and show that this is a sufficient bias model for the corresponding cosmology analysis.

  16. Weak lensing by galaxy troughs in DES Science Verification data

    DOE PAGESBeta

    Gruen, D.; Friedrich, O.; Amara, A.; Bacon, D.; Bonnett, C.; Hartley, W.; Jain, B.; M. Jarvis; Kavprzak, T.; Krause, E.; et al

    2015-11-29

    In this study, we measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ–15σ for the smallest angular scales) for troughs with the redshift range z ϵ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers ofmore » the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. The prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. The lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.« less

  17. Weak lensing by galaxy troughs in DES Science Verification data

    SciTech Connect

    Gruen, D.; Friedrich, O.; Amara, A.; Bacon, D.; Bonnett, C.; Hartley, W.; Jain, B.; M. Jarvis; Kavprzak, T.; Krause, E.; Mana, A.; Rozo, E.; Rykoff, E. S.; Seitz, S.; Sheldon, E.; Troxel, M. A.; Vikram, V.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Armstrong, R.; Banerji, M.; Bauer, A. H.; Becker, M. R.; Benoit-Levy, A.; Bernstein, G. M.; Bernstein, R. A.; Bertin, E.; Bridle, S. L.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Rosell, A. Carnero; Carretero, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Neto, A. Fausti; Fernandez, E.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gerdes, D. W.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; Maia, M. A. G.; March, M.; Martini, P.; Melchior, P.; Miller, C. J.; Miguel, R.; Mohr, J. J.; Nord, B.; Orgando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Walker, A. R.; Wechsler, R. H.; Weller, J.; Zhang, Y.; Zuntz, J.

    2015-11-29

    In this study, we measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ–15σ for the smallest angular scales) for troughs with the redshift range z ϵ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers of the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. The prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. The lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.

  18. Weak Lensing by Galaxy Troughs in DES Science Verification Data

    SciTech Connect

    Gruen, D.

    2015-09-29

    We measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ–15σ for the smallest angular scales) for troughs with the redshift range z ϵ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers of the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. Furthermore, the prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. Finally, the lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.

  19. Weak lensing by galaxy troughs in DES Science Verification data

    NASA Astrophysics Data System (ADS)

    Gruen, D.; Friedrich, O.; Amara, A.; Bacon, D.; Bonnett, C.; Hartley, W.; Jain, B.; Jarvis, M.; Kacprzak, T.; Krause, E.; Mana, A.; Rozo, E.; Rykoff, E. S.; Seitz, S.; Sheldon, E.; Troxel, M. A.; Vikram, V.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Armstrong, R.; Banerji, M.; Bauer, A. H.; Becker, M. R.; Benoit-Lévy, A.; Bernstein, G. M.; Bernstein, R. A.; Bertin, E.; Bridle, S. L.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Neto, A. Fausti; Fernandez, E.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gerdes, D. W.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; Maia, M. A. G.; March, M.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Mohr, J. J.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Walker, A. R.; Wechsler, R. H.; Weller, J.; Zhang, Y.; Zuntz, J.

    2016-01-01

    We measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ-15σ for the smallest angular scales) for troughs with the redshift range z ∈ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers of the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. The prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. The lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.

  20. Cross-correlation of gravitational lensing from DES Science Verification data with SPT and Planck lensing

    SciTech Connect

    Kirk, D.; et al.

    2015-12-14

    We measure the cross-correlation between weak lensing of galaxy images and of the cosmic microwave background (CMB). The effects of gravitational lensing on different sources will be correlated if the lensing is caused by the same mass fluctuations. We use galaxy shape measurements from 139 deg$^{2}$ of the Dark Energy Survey (DES) Science Verification data and overlapping CMB lensing from the South Pole Telescope (SPT) and Planck. The DES source galaxies have a median redshift of $z_{\\rm med} {\\sim} 0.7$, while the CMB lensing kernel is broad and peaks at $z{\\sim}2$. The resulting cross-correlation is maximally sensitive to mass fluctuations at $z{\\sim}0.44$. Assuming the Planck 2015 best-fit cosmology, the amplitude of the DES$\\times$SPT cross-power is found to be $A = 0.88 \\pm 0.30$ and that from DES$\\times$Planck to be $A = 0.86 \\pm 0.39$, where $A=1$ corresponds to the theoretical prediction. These are consistent with the expected signal and correspond to significances of $2.9 \\sigma$ and $2.2 \\sigma$ respectively. We demonstrate that our results are robust to a number of important systematic effects including the shear measurement method, estimator choice, photometric redshift uncertainty and CMB lensing systematics. Significant intrinsic alignment of galaxy shapes would increase the cross-correlation signal inferred from the data; we calculate a value of $A = 1.08 \\pm 0.36$ for DES$\\times$SPT when we correct the observations with a simple IA model. With three measurements of this cross-correlation now existing in the literature, there is not yet reliable evidence for any deviation from the expected LCDM level of cross-correlation, given the size of the statistical uncertainties and the significant impact of systematic errors, particularly IAs. We provide forecasts for the expected signal-to-noise of the combination of the five-year DES survey and SPT-3G.

  1. Mapping and Simulating Systematics Due to Spatially-Varying Observing Conditions in DES Science Verification Data

    SciTech Connect

    Leistedt, B.

    2015-07-20

    Spatially-varying depth and characteristics of observing conditions, such as seeing, airmass, or sky background, are major sources of systematic uncertainties in modern galaxy survey analyses, in particular in deep multi-epoch surveys. We present a framework to extract and project these sources of systematics onto the sky, and apply it to the Dark Energy Survey (DES) to map the observing conditions of the Science Verification (SV) data. The resulting distributions and maps of sources of systematics are used in several analyses of DES SV to perform detailed null tests with the data, and also to incorporate systematics in survey simulations. We illustrate the complementarity of these two approaches by comparing the SV data with the BCC-UFig, a synthetic sky catalogue generated by forward-modelling of the DES SV images. We then analyse the BCC-UFig simulation to construct galaxy samples mimicking those used in SV galaxy clustering studies. We show that the spatially-varying survey depth imprinted in the observed galaxy densities and the redshift distributions of the SV data are successfully reproduced by the simulation and well-captured by the maps of observing conditions. The combined use of the maps, the SV data and the BCC-UFig simulation allows us to quantify the impact of spatial systematics on N(z), the redshift distributions inferred using photometric redshifts. We conclude that spatial systematics in the SV data are mainly due to seeing fluctuations and are under control in current clustering and weak lensing analyses. However, they will need to be carefully characterised in upcoming phases of DES in order to avoid biasing the inferred cosmological results. The framework presented is relevant to all multi-epoch surveys, and will be essential for exploiting future surveys such as the Large Synoptic Survey Telescope, which will require detailed null-tests and realistic end-to-end image simulations to correctly interpret the deep, high-cadence observations of the sky.

  2. The RedMaPPer Galaxy Cluster Catalog From DES Science Verification Data

    NASA Astrophysics Data System (ADS)

    Rykoff, E. S.; Rozo, E.; Hollowood, D.; Bermeo-Hernandez, A.; Jeltema, T.; Mayers, J.; Romer, A. K.; Rooney, P.; Saro, A.; Vergara Cervantes, C.; Wechsler, R. H.; Wilcox, H.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bernstein, G. M.; Bertin, E.; Brooks, D.; Burke, D. L.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Castander, F. J.; Childress, M.; Collins, C. A.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; Davis, T. M.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Evrard, A. E.; Finley, D. A.; Flaugher, B.; Fosalba, P.; Frieman, J.; Glazebrook, K.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Hilton, M.; Honscheid, K.; Hoyle, B.; James, D. J.; Kay, S. T.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Lewis, G. F.; Lidman, C.; Lima, M.; Maia, M. A. G.; Mann, R. G.; Marshall, J. L.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Sahlén, M.; Sanchez, E.; Santiago, B.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Stott, J. P.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Tucker, D.; Uddin, S.; Viana, P. T. P.; Vikram, V.; Walker, A. R.; Zhang, Y.; The DES Collaboration

    2016-05-01

    We describe updates to the redMaPPer algorithm, a photometric red-sequence cluster finder specifically designed for large photometric surveys. The updated algorithm is applied to 150 {{deg}}2 of Science Verification (SV) data from the Dark Energy Survey (DES), and to the Sloan Digital Sky Survey (SDSS) DR8 photometric data set. The DES SV catalog is locally volume limited and contains 786 clusters with richness λ \\gt 20 (roughly equivalent to {M}{{500c}}≳ {10}14 {h}70-1 {M}ȯ ) and 0.2\\lt z\\lt 0.9. The DR8 catalog consists of 26,311 clusters with 0.08\\lt z\\lt 0.6, with a sharply increasing richness threshold as a function of redshift for z≳ 0.35. The photometric redshift performance of both catalogs is shown to be excellent, with photometric redshift uncertainties controlled at the {σ }z/(1+z)∼ 0.01 level for z≲ 0.7, rising to ∼0.02 at z∼ 0.9 in DES SV. We make use of Chandra and XMM X-ray and South Pole Telescope Sunyaev–Zeldovich data to show that the centering performance and mass–richness scatter are consistent with expectations based on prior runs of redMaPPer on SDSS data. We also show how the redMaPPer photo-z and richness estimates are relatively insensitive to imperfect star/galaxy separation and small-scale star masks.

  3. Cross-correlation of gravitational lensing from DES Science Verification data with SPT and Planck lensing

    NASA Astrophysics Data System (ADS)

    Kirk, D.; Omori, Y.; Benoit-Lévy, A.; Cawthon, R.; Chang, C.; Larsen, P.; Amara, A.; Bacon, D.; Crawford, T. M.; Dodelson, S.; Fosalba, P.; Giannantonio, T.; Holder, G.; Jain, B.; Kacprzak, T.; Lahav, O.; MacCrann, N.; Nicola, A.; Refregier, A.; Sheldon, E.; Story, K. T.; Troxel, M. A.; Vieira, J. D.; Vikram, V.; Zuntz, J.; Abbott, T. M. C.; Abdalla, F. B.; Becker, M. R.; Benson, B. A.; Bernstein, G. M.; Bernstein, R. A.; Bleem, L. E.; Bonnett, C.; Bridle, S. L.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carlstrom, J. E.; Rosell, A. Carnero; Kind, M. Carrasco; Carretero, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Evrard, A. E.; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D. J.; Jarvis, M.; Kent, S.; Kuehn, K.; Kuropatkin, N.; Lima, M.; March, M.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Nichol, R. C.; Ogando, R.; Plazas, A. A.; Reichardt, C. L.; Roodman, A.; Rozo, E.; Rykoff, E. S.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Simard, G.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Wechsler, R. H.; Weller, J.

    2016-06-01

    We measure the cross-correlation between weak lensing of galaxy images and of the cosmic microwave background (CMB). The effects of gravitational lensing on different sources will be correlated if the lensing is caused by the same mass fluctuations. We use galaxy shape measurements from 139 deg2 of the Dark Energy Survey (DES) Science Verification data and overlapping CMB lensing from the South Pole Telescope (SPT) and Planck. The DES source galaxies have a median redshift of zmed ˜ 0.7, while the CMB lensing kernel is broad and peaks at z ˜ 2. The resulting cross-correlation is maximally sensitive to mass fluctuations at z ˜ 0.44. Assuming the Planck 2015 best-fitting cosmology, the amplitude of the DES×SPT cross-power is found to be ASPT = 0.88 ± 0.30 and that from DES×Planck to be APlanck = 0.86 ± 0.39, where A = 1 corresponds to the theoretical prediction. These are consistent with the expected signal and correspond to significances of 2.9σ and 2.2σ, respectively. We demonstrate that our results are robust to a number of important systematic effects including the shear measurement method, estimator choice, photo-z uncertainty and CMB lensing systematics. We calculate a value of A = 1.08 ± 0.36 for DES×SPT when we correct the observations with a simple intrinsic alignment model. With three measurements of this cross-correlation now existing in the literature, there is not yet reliable evidence for any deviation from the expected LCDM level of cross-correlation. We provide forecasts for the expected signal-to-noise ratio of the combination of the five-year DES survey and SPT-3G.

  4. Galaxy bias from the DES Science Verification data: combining galaxy density maps and weak lensing maps

    NASA Astrophysics Data System (ADS)

    Chang, C.; Pujol, A.; Gaztañaga, E.; Amara, A.; Réfrégier, A.; Bacon, D.; Becker, M. R.; Bonnett, C.; Carretero, J.; Castander, F. J.; Crocce, M.; Fosalba, P.; Giannantonio, T.; Hartley, W.; Jarvis, M.; Kacprzak, T.; Ross, A. J.; Sheldon, E.; Troxel, M. A.; Vikram, V.; Zuntz, J.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Rosell, A. Carnero; Kind, M. Carrasco; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Estrada, J.; Evrard, A. E.; Flaugher, B.; Frieman, J.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; Jain, B.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Rykoff, E. S.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Walker, A. R.

    2016-04-01

    We measure the redshift evolution of galaxy bias for a magnitude-limited galaxy sample by combining the galaxy density maps and weak lensing shear maps for a ˜116 deg2 area of the Dark Energy Survey (DES) Science Verification data. This method was first developed in Amara et al. (2012) and later re-examined in a companion paper (Pujol et al. 2016) with rigorous simulation tests and analytical treatment of tomographic measurements. In this work we apply this method to the DES SV data and measure the galaxy bias for a i < 22.5 galaxy sample. We find the galaxy bias and 1σ error bars in 4 photometric redshift bins to be 1.12 ± 0.19 (z = 0.2 - 0.4), 0.97 ± 0.15 (z = 0.4 - 0.6), 1.38 ± 0.39 (z = 0.6 - 0.8), and 1.45 ± 0.56 (z = 0.8 - 1.0). These measurements are consistent at the 2σ level with measurements on the same dataset using galaxy clustering and cross-correlation of galaxies with CMB lensing, with most of the redshift bins consistent within the 1σ error bars. In addition, our method provides the only σ8-independent constraint among the three. We forward-model the main observational effects using mock galaxy catalogs by including shape noise, photo-z errors and masking effects. We show that our bias measurement from the data is consistent with that expected from simulations. With the forthcoming full DES data set, we expect this method to provide additional constraints on the galaxy bias measurement from more traditional methods. Furthermore, in the process of our measurement, we build up a 3D mass map that allows further exploration of the dark matter distribution and its relation to galaxy evolution.

  5. Cross-correlation of gravitational lensing from DES Science Verification data with SPT and Planck lensing

    NASA Astrophysics Data System (ADS)

    Kirk, D.; Omori, Y.; Benoit-Lévy, A.; Cawthon, R.; Chang, C.; Larsen, P.; Amara, A.; Bacon, D.; Crawford, T. M.; Dodelson, S.; Fosalba, P.; Giannantonio, T.; Holder, G.; Jain, B.; Kacprzak, T.; Lahav, O.; MacCrann, N.; Nicola, A.; Refregier, A.; Sheldon, E.; Story, K. T.; Troxel, M. A.; Vieira, J. D.; Vikram, V.; Zuntz, J.; Abbott, T. M. C.; Abdalla, F. B.; Becker, M. R.; Benson, B. A.; Bernstein, G. M.; Bernstein, R. A.; Bleem, L. E.; Bonnett, C.; Bridle, S. L.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carlstrom, J. E.; Rosell, A. Carnero; Kind, M. Carrasco; Carretero, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Evrard, A. E.; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D. J.; Jarvis, M.; Kent, S.; Kuehn, K.; Kuropatkin, N.; Lima, M.; March, M.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Nichol, R. C.; Ogando, R.; Plazas, A. A.; Reichardt, C. L.; Roodman, A.; Rozo, E.; Rykoff, E. S.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Simard, G.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Wechsler, R. H.; Weller, J.

    2016-03-01

    We measure the cross-correlation between weak lensing of galaxy images and of the cosmic microwave background (CMB). The effects of gravitational lensing on different sources will be correlated if the lensing is caused by the same mass fluctuations. We use galaxy shape measurements from 139 deg2 of the Dark Energy Survey (DES) Science Verification data and overlapping CMB lensing from the South Pole Telescope (SPT) and Planck. The DES source galaxies have a median redshift of zmed ˜ 0.7, while the CMB lensing kernel is broad and peaks at z ˜ 2. The resulting cross-correlation is maximally sensitive to mass fluctuations at z ˜ 0.44. Assuming the Planck 2015 best-fit cosmology, the amplitude of the DESSPT cross-power is found to be ASPT = 0.88 ± 0.30 and that from DES×Planck to be A_{Planck} = 0.86 ± 0.39, where A = 1 corresponds to the theoretical prediction. These are consistent with the expected signal and correspond to significances of 2.9σ and 2.2σ respectively. We demonstrate that our results are robust to a number of important systematic effects including the shear measurement method, estimator choice, photo-z uncertainty and CMB lensing systematics. We calculate a value of A = 1.08 ± 0.36 for DES×SPT when we correct the observations with a simple IA model. With three measurements of this cross-correlation now existing in the literature, there is not yet reliable evidence for any deviation from the expected LCDM level of cross-correlation. We provide forecasts for the expected signal-to-noise of the combination of the five-year DES survey and SPT-3G.

  6. redMaGiC. Selecting Luminous Red Galaxies from the DES Science Verification Data

    SciTech Connect

    Rozo, E.

    2015-07-20

    We introduce redMaGiC, an automated algorithm for selecting Luminous Red Galaxies (LRGs). The algorithm was developed to minimize photometric redshift uncertainties in photometric large-scale structure studies. redMaGiC achieves this by self-training the color-cuts necessary to produce a luminosity-thresholded LRG sam- ple of constant comoving density. Additionally, we demonstrate that redMaGiC photo-zs are very nearly as accurate as the best machine-learning based methods, yet they require minimal spectroscopic training, do not suffer from extrapolation biases, and are very nearly Gaussian. We apply our algorithm to Dark Energy Survey (DES) Science Verification (SV) data to produce a redMaGiC catalog sampling the redshift range z ϵ [0.2,0.8]. Our fiducial sample has a comoving space density of 10-3 (h-1Mpc)-3, and a median photo-z bias (zspec zphoto) and scatter (σz=(1 + z)) of 0.005 and 0.017 respectively.The corresponding 5σ outlier fraction is 1.4%. We also test our algorithm with Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8) and Stripe 82 data, and discuss how spectroscopic training can be used to control photo-z biases at the 0.1% level.

  7. L'eclairage de la recherche sur la situation et le point de vue des enseignants de sciences du primaire et ses repercussions sur leur formation continue en ce domaine

    NASA Astrophysics Data System (ADS)

    Roy, Jean A.

    Cette these par articles comporte deux textes successivement consacres (1) a elaborer un modele causal hierarchique des facteurs qui se repercutent sur l'enseignement de sciences de l'enseignant du primaire, et (2) a degager puis a analyser la representation du point de vue des enseignants de sciences du primaire et du secondaire qui emerge de la recherche qualitative qui leur est consacree. L'essentiel des conclusions de ces articles tient aux faits suivants: (1) au primaire, la prestation d'enseignement des sciences de l'enseignant serait directement determinee par ses "preferences" au plan des pratiques d'enseignement, par ses attitudes a l'egard des sciences et de leur enseignement et par son sentiment d'efficacite personnelle en ce domaine; (2) l'action de l'enseignant de sciences du primaire tout autant que du secondaire est confrontee a des dilemmes pedagogiques dont la resolution obeit a des regles qui tiennent moins souvent a des principes abstraits ou bien etablis qu'aux exigences variables et tres contextualisees de l'"ici et maintenant" de sa classe. Chacun des deux articles est par ailleurs complete par un texte substantiel qui propose des clarifications et des donnees complementaires qui en precisent la portee et qui en relient plus directement le contenu au propos de cette these: la formation initiale et surtout continue des enseignants du primaire dans le domaine de l'enseignement des sciences. S'articulant tous autour de l'enseignant de sciences et s'appuyant chaque fois sur un travail de recension de la recherche adapte a la nature particuliere de la problematique qui y est traitee, ces articles et les textes qui les accompagnent veulent contribuer a mieux eclairer et a resoudre la situation problematique de l'enseignement des sciences au primaire, un enseignement qui est souvent caracterise par des pratiques pedagogiques traditionnelles et inadequates, si ce n'est meme par son evitement plus ou moins delibere par les enseignants. Apres avoir decrit les avancees methodologiques qu'ont occasionne les approches differenciees de recension auxquelles les deux articles ont donne lieu, cette recherche debouche sur une reflexion sur les conditions necessaires d'une formation plus adequate des enseignants de sciences du primaire a l'egard de leur maitrise des savoirs disciplinaires, de leur formation initiale a la pratique ainsi que de la mise a jour continuee de leurs pratiques d'enseignement. On conclut enfin en mesurant l'ampleur de la transformation necessaire des conceptions des formateurs de maitres qui s'engageraient dans une telle reforme de la formation initiale et continuee des enseignants de sciences du primaire.

  8. Galaxy Clustering, Photometric Redshifts and Diagnosis of Systematics in the DES Science Verification Data

    DOE PAGESBeta

    Crocce, M.

    2015-12-09

    We study the clustering of galaxies detected at i < 22.5 in the Science Verification observations of the Dark Energy Survey (DES). Two-point correlation functions are measured using 2.3 × 106 galaxies over a contiguous 116 deg2 region in five bins of photometric redshift width Δz = 0.2 in the range 0.2 < z < 1.2. The impact of photometric redshift errors is assessed by comparing results using a template-based photo-zalgorithm (BPZ) to a machine-learning algorithm (TPZ). A companion paper presents maps of several observational variables (e.g. seeing, sky brightness) which could modulate the galaxy density. Here we characterize andmore » mitigate systematic errors on the measured clustering which arise from these observational variables, in addition to others such as Galactic dust and stellar contamination. After correcting for systematic effects, we then measure galaxy bias over a broad range of linear scales relative to mass clustering predicted from the Planck Λ cold dark matter model, finding agreement with the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) measurements with χ2 of 4.0 (8.7) with 5 degrees of freedom for the TPZ (BPZ) redshifts. Furthermore, we test a ‘linear bias’ model, in which the galaxy clustering is a fixed multiple of the predicted non-linear dark matter clustering. The precision of the data allows us to determine that the linear bias model describes the observed galaxy clustering to 2.5 percent accuracy down to scales at least 4–10 times smaller than those on which linear theory is expected to be sufficient.« less

  9. Galaxy Clustering, Photometric Redshifts and Diagnosis of Systematics in the DES Science Verification Data

    SciTech Connect

    Crocce, M.

    2015-12-09

    We study the clustering of galaxies detected at i < 22.5 in the Science Verification observations of the Dark Energy Survey (DES). Two-point correlation functions are measured using 2.3 × 106 galaxies over a contiguous 116 deg2 region in five bins of photometric redshift width Δz = 0.2 in the range 0.2 < z < 1.2. The impact of photometric redshift errors is assessed by comparing results using a template-based photo-zalgorithm (BPZ) to a machine-learning algorithm (TPZ). A companion paper presents maps of several observational variables (e.g. seeing, sky brightness) which could modulate the galaxy density. Here we characterize and mitigate systematic errors on the measured clustering which arise from these observational variables, in addition to others such as Galactic dust and stellar contamination. After correcting for systematic effects, we then measure galaxy bias over a broad range of linear scales relative to mass clustering predicted from the Planck Λ cold dark matter model, finding agreement with the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) measurements with χ2 of 4.0 (8.7) with 5 degrees of freedom for the TPZ (BPZ) redshifts. Furthermore, we test a ‘linear bias’ model, in which the galaxy clustering is a fixed multiple of the predicted non-linear dark matter clustering. The precision of the data allows us to determine that the linear bias model describes the observed galaxy clustering to 2.5 percent accuracy down to scales at least 4–10 times smaller than those on which linear theory is expected to be sufficient.

  10. Galaxy clustering, photometric redshifts and diagnosis of systematics in the DES Science Verification data

    NASA Astrophysics Data System (ADS)

    Crocce, M.; Carretero, J.; Bauer, A. H.; Ross, A. J.; Sevilla-Noarbe, I.; Giannantonio, T.; Sobreira, F.; Sanchez, J.; Gaztanaga, E.; Kind, M. Carrasco; Sánchez, C.; Bonnett, C.; Benoit-Lévy, A.; Brunner, R. J.; Rosell, A. Carnero; Cawthon, R.; Fosalba, P.; Hartley, W.; Kim, E. J.; Leistedt, B.; Miquel, R.; Peiris, H. V.; Percival, W. J.; Rosenfeld, R.; Rykoff, E. S.; Sánchez, E.; Abbott, T.; Abdalla, F. B.; Allam, S.; Banerji, M.; Bernstein, G. M.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Castander, F. J.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Eifler, T. F.; Evrard, A. E.; Neto, A. Fausti; Fernandez, E.; Finley, D. A.; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; Maia, M. A. G.; March, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Miller, C. J.; Neilsen, E.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Romer, A. K.; Sako, M.; Santiago, B.; Schubnell, M.; Smith, R. C.; Soares-Santos, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Vikram, V.; Walker, A. R.; Wechsler, R. H.; Weller, J.; Zuntz, J.; DES Collaboration

    2016-02-01

    We study the clustering of galaxies detected at i < 22.5 in the Science Verification observations of the Dark Energy Survey (DES). Two-point correlation functions are measured using 2.3 × 106 galaxies over a contiguous 116 deg2 region in five bins of photometric redshift width Δz = 0.2 in the range 0.2 < z < 1.2. The impact of photometric redshift errors is assessed by comparing results using a template-based photo-z algorithm (BPZ) to a machine-learning algorithm (TPZ). A companion paper presents maps of several observational variables (e.g. seeing, sky brightness) which could modulate the galaxy density. Here we characterize and mitigate systematic errors on the measured clustering which arise from these observational variables, in addition to others such as Galactic dust and stellar contamination. After correcting for systematic effects, we measure galaxy bias over a broad range of linear scales relative to mass clustering predicted from the Planck Λ cold dark matter model, finding agreement with the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) measurements with χ2 of 4.0 (8.7) with 5 degrees of freedom for the TPZ (BPZ) redshifts. We test a `linear bias' model, in which the galaxy clustering is a fixed multiple of the predicted non-linear dark matter clustering. The precision of the data allows us to determine that the linear bias model describes the observed galaxy clustering to 2.5 per cent accuracy down to scales at least 4-10 times smaller than those on which linear theory is expected to be sufficient.

  11. Evaluation d'une approche pedagogique respectant les facons d'apprendre des filles en sciences et en TIC en 9e annee au Nouveau-Brunswick

    NASA Astrophysics Data System (ADS)

    Lirette-Pitre, Nicole T.

    2009-07-01

    La reussite scolaire des filles les amene de plus en plus a poursuivre une formation postsecondaire et a exercer des professions qui demandent un haut niveau de connaissances et d'expertise scientifique. Toutefois, les filles demeurent toujours tres peu nombreuses a envisager une carriere en sciences (chimie et physique), en ingenierie ou en TIC (technologie d'information et de la communication), soit une carriere reliee a la nouvelle economie. Pour plusieurs filles, les sciences et les TIC ne sont pas des matieres scolaires qu'elles trouvent interessantes meme si elles y reussissent tres bien. Ces filles admettent que leurs experiences d'apprentissage en sciences et en TIC ne leur ont pas permis de developper un interet ni de se sentir confiante en leurs habiletes a reussir dans ces matieres. Par consequent, peu de filles choisissent de poursuivre leurs etudes postsecondaires dans ces disciplines. La theorie sociocognitive du choix carriere a ete choisie comme modele theorique pour mieux comprendre quelles variables entrent en jeu lorsque les filles choisissent leur carriere. Notre etude a pour objet la conception et l'evaluation de l'efficacite d'un materiel pedagogique concu specifiquement pour ameliorer les experiences d'apprentissage en sciences et en TIC des filles de 9e annee au Nouveau-Brunswick. L'approche pedagogique privilegiee dans notre materiel a mis en oeuvre des strategies pedagogiques issues des meilleures pratiques que nous avons identifiees et qui visaient particulierement l'augmentation du sentiment d'auto-efficacite et de l'interet des filles pour ces disciplines. Ce materiel disponible par Internet a l'adresse http://www.umoncton.ca/lirettn/scientic est directement en lien avec le programme d'etudes en sciences de la nature de 9e annee du Nouveau-Brunswick. L'evaluation de l'efficacite de notre materiel pedagogique a ete faite selon deux grandes etapes methodologiques: 1) l'evaluation de l'utilisabilite et de la convivialite du materiel et 2) l'evaluation de l'effet du materiel en fonction de diverses variables reliees a l'interet et au sentiment d'auto-efficacite des filles en sciences et en TIC. Cette recherche s'est inscrite dans un paradigme pragmatique de recherche. Le pragmatisme a guide nos choix en ce qui a trait au modele de recherche et des techniques utilisees. Cette recherche a associe a la fois des techniques qualitatives et quantitatives, particulierement en ce qui concerne la collecte et l'analyse de donnees. Les donnees recueillies dans la premiere etape de l'evaluation de l'utilisabilite et de la convivialite du materiel par les enseignantes et les enseignants de sciences et les filles ont revele que le materiel concu est tres utilisable et convivial. Toutefois quelques petites ameliorations seront apportees a une version subsequente afin de faciliter davantage la navigation. Quant a l'evaluation des effets du materiel concu sur les variables reliees au sentiment d'auto-efficacite et aux interets lors de l'etape quasi experimentale, nos donnees qualitatives ont indique que ce materiel a eu des effets positifs sur le sentiment d'auto-efficacite et sur les interets des filles qui l'ont utilise. Toutefois, nos donnees quantitatives n'ont pas permis d'inferer un lien causal direct entre l'utilisation du materiel et l'augmentation du sentiment d'auto-efficacite et des interets des filles en sciences et en TIC. A la lumiere des resultats obtenus, nous avons conclu que le materiel a eu les effets escomptes. Donc, nous recommandons la creation et l'utilisation de materiel de ce genre dans toutes les classes de sciences de la 6e annee a la 12e annee au Nouveau-Brunswick.

  12. Austausch universitärer Kernsysteme

    NASA Astrophysics Data System (ADS)

    Borgeest, Rolf; Pongratz, Hans

    Das Projekt IntegraTUM hatte die Schaffung einer benutzerfreundlichen nahtlosen Informations- und Kommunikationsinfrastruktur (IuK) an der Technischen Universität München (TUM) zum Ziel. Die dazu betriebene Konsolidierung und Integration von universitären Kernsystemen führte zu wiederholten Migrationen von Altsystemen auf neue Systeme. Dieser Beitrag beschreibt universitäre Systemlandschaften, nennt Kriterien für die Auswahl der zu konsolidierenden Systeme und geht speziell auf die Situation an der TUM ein. Nach einer Klassifikation von verschiedenen Arten von Systemwechseln werden notwendige Migrationsschritte anhand eines größeren Beispiels erläutert. Am Schluss diskutieren wir wichtige Erfolgsfaktoren für die erreichte Konsolidierung und Integration der Systemlandschaft.

  13. Grundsätze über die Anlagen neuer Sternwarten mit Beziehung auf die Sternwarte der Universität Göttingen. Von Georg Heinrich Borheck

    NASA Astrophysics Data System (ADS)

    Beuermann, Klaus; Borheck, Georg Heinrich

    Die Göttinger Sternwarte, Wirkungsstätte des berühmten Gelehrten Carl Friedrich Gauß, ist ein bedeutendes Baudenkmal. Im Jahre 2005 wird sie gemeinsam von der Georg-August-Universität und der Akademie der Wissenschaften zu Göttingen renoviert, um dann als repräsentatives Gebäude der Universität und Arbeitsstätte der Akademie zu dienen. Die Nutzung der historischen Räume für Ausstellungen macht diesen imposanten Bau erstmals der Öffentlichkeit zugänglich. Die Sternwarte war bei ihrer Errichtung vor 200 Jahren ein nach seinerzeit neuesten wissenschaftlichen Erkenntnissen konzipierter Bau, der die Universität Göttingen in eine der vordersten Stellen Europa rückte. Auch aufgrund ihrer Architektur ist sie ein großer Wurf des Göttinger Universitätsbaumeisters Georg Heinrich Borheck. Durch die Kriegswirren der Napoleonischen Zeit zerschlug sich Borhecks Versuch einer Publikation seiner Beschreibung des Baus der Göttinger Sternwarte 1805. Doch seine Schrift ist auch heute noch aktuell und wird mit diesem Band erstmals einer breiten Öffentlichkeit zugängig gemacht. Er zeigt die Grundsätze, nach denen damals öffentliche Bauten konzipiert wurden, erläutert die Bedeutung des Baus aus kunst- und wissenschaftshistorischer Sicht und informiert über die Pläne zur Restaurierung der Sternwarte in einem separaten Beitrag und im Geleitwort des Präsidenten der Georg-August Universität Prof. Dr. Dr. h. c. Kurt von Figura.

  14. Traitements didactiques preventifs d'un type de conceptions erronees en sciences physiques chez des eleves du secondaire

    NASA Astrophysics Data System (ADS)

    Blondin, Andre

    Dans un contexte constructiviste, les connaissances anterieures d'un individu sont essentielles a la construction de nouvelles connaissances. Quelle qu'en soit la source (certaines de ces connaissances ont ete elaborees en classe, d'autres ont ete elaborees par interaction personnelle de l'individu avec son environnement physique et social), ces connaissances, une fois acquises, constituent les matieres premieres de l'elaboration des nouvelles conceptions de cet individu. Generalement, cette influence est consideree comme positive. Cependant, dans un milieu scolaire ou l'apprentissage de certaines conceptions enchassees dans un programme d'etudes et enterinees par l'ensemble d'une communaute est obligatoire, certaines connaissances anterieures peuvent entraver la construction des conceptions exigees par la communaute. La litterature abonde de tels exemples. Cependant, certaines connaissances anterieures, en soi tout a fait conformes a l'Heritage, peuvent aussi, parce qu'utilisees de facon non pertinente, entraver la construction d'une conception exigee par la communaute. Ici, la litterature nous donne peu d'exemples de ce type, mais nous en fournirons quelques-uns dans le cadre theorique, et ce sera un d'entre eux qui servira de base a nos propos. En effet, une grande proportion d'eleves inscrits a un cours de sciences physiques de la quatrieme secondaire, en reponse a un probleme deja solutionne durant l'annee et redonne lors d'un examen sommatif, "Pourquoi la Lune nous montre-t-elle toujours la meme face?", attribue principalement la cause de ce phenomene a la rotation de la Terre sur son axe. En tant que responsable de l'enseignement de ce programme d'etudes, plusieurs questions nous sont venues a l'esprit, entre autres, comment, dans un contexte constructiviste, est-il possible de reduire chez un eleve, l'impact de cette connaissance anterieure dans l'elaboration de la solution et ainsi prevenir la construction d'une conception erronee? Nous avons teste nos hypotheses avec la cohorte suivante d'eleves chez qui se repetaient les memes conditions d'apprentissage. Nous avons utilise le design de recherche "posttest only" de Campbell et Stanley. En mai, apres le moment prevu dans la planification du programme pour donner le probleme aux eleves, nous avons suggere deux facons differentes de reviser la solution de ce probleme. Les eleves du premier groupe experimental ont revise sans que soit activee la connaissance anterieure apprehendee de la rotation de la Terre. Les eleves du deuxieme groupe experimental ont ete confrontes, par des questions et une simulation, au fait que la rotation de la Terre n'est pas une connaissance pertinente pour resoudre le probleme. Les groupes temoins et les groupes experimentaux ont ete choisis au hasard dans le bassin des ecoles secondaires de la commission scolaire. (Abstract shortened by UMI.)

  15. Science and Technology Facilities

    ERIC Educational Resources Information Center

    Moonen, Jean-Marie; Buono, Nicolas; Handfield, Suzanne

    2004-01-01

    These four articles relate to science and technology infrastructure for secondary and tertiary institutions. The first article presents a view on approaches to teaching science in school and illustrates ideal science facilities for secondary education. The second piece reports on work underway to improve the Science Complex at the "Universite du…

  16. Du changement conceptuel a la complexification conceptuelle dans l'apprentissage des sciences

    NASA Astrophysics Data System (ADS)

    Belanger, Michel

    Science learning has often been thought as a replacement process; learners' spontaneous ideas must be replaced by scientific ones. Many learning models in science education were formulated in this way (at least implicitly). But theses spontaneous ideas proved to be more resistant than initially thought. Several researchers concluded that students often possess an odd combination of intuitive and scientific ideas. Generally, the phenomenon of "multiple conceptions" refers to students having a repertoire of different conceptions, each associated with a context of relevance. A number of researchers in science education constructed models of this phenomenon, but none included a systematic treatment of what we consider one of its most important aspects: the fact that these multiple conceptions are not isolated within the cognitive structure, but integrated into a whole in many ways. This whole constitute a complex of conceptions, whence our utilisation of the expression "conceptual complexification" to designate this form of learning. Using ideas in the conceptual change literature and in philosophy of science, we propose five kinds of cognitive structures that could play an intermediary role between alternative conceptions, allowing the management of their multiplicity: descriptive, evaluative, explicative, transformative, and decisional. In the empirical section of the research, we explore specifically decisional structures, which are responsible for the selection of one conception of the repertoire. In order to do so, we submitted two series of tasks to eight collegial and undergraduate students in two situations. In the first tasks, subjects are asked to explain three phenomena (one biological and two physical) to fictive audiences of various ages (6 to 15 years old). In the second tasks, students' understanding of the quantum version of the Young's interference experiment is probed in order study their understanding of the demarcation between quantum and classical mechanics. In these two situations, students appear to make use of two different strategies for selecting between alternative conceptions. Many topics of science education are briefly touched in this research. The conceptual complexification model that we propose could constitute an interesting theoretical framework for their future study. Keywords: conceptual change, multiple conceptions, conceptual complexification, quantum mechanic learning, popularization, history of science.

  17. Analyse des attitudes envers les sciences chez des eleves du secondaire d'origine haitienne de milieux defavorises de la region de Montreal

    NASA Astrophysics Data System (ADS)

    Fils-Aime, Nestor

    Having in perspective the slight representativeness of students, from Haitian background, from the most unprivileged sections of the great region of Montreal in the scientific fields in High School and in the choices of career, this study intends to examine the effect of the individual characteristics as well as the associated factors related to the familial, scholastic, socio-economic, and cultural environment upon the attitudes of those students toward sciences. The analysis of the datum is based on the results of a questionnaire focusing on the socio-demographic profile of a group of students from fourth and fifth year attending two multiethnic High Schools of the North-Crown of Montreal as well as on the interviews with fifteen of those students who are from a haitian background. There were also interviews with some parents, a member of a community organism, some staff members of some schools as well as some Haitian-Quebecer professionals and scientists, in order to have a critical viewpoint upon the different positions expressed by the fifteen students. The Bronfenbrenner's ecosystemic model (1979, 1986) has been used as scope of reference allowing to draw the prominent aspects from the attitudes toward science in the students, from haitian background. The synthesis of ideas expressed by different interviewee reveals the existence of a environment not much enhancing the value of sciences around of students, from Haitian background. The socio-economic conditions, the familial practices, the ethnocultural status as well as some individual representations of sciences contribute to create and maintain some attitudes very little committed to sciences in those students. The study shows how much it is urgent to demystify the sciences by breaking with some stereotypes that prevent some categories of students from acceding to sciences. It also commands to politicians, concerning education, to be more open to ethnocultural differences and to explore some dynamic ways in order to make the scientific culture accessible to all social groups. Key words: science learning, attitudes toward science, multiethnicity, ecosystemic model, environmental factors, High School students, immigration, socio-economic status, ethnocultural status, haitian background, econominically disadvantaged area, students attitudes.

  18. Making mobile knowledges. The educational cruises of the Revue Générale des Sciences Pures et Appliquées, 1897-1914.

    PubMed

    della Dora, Veronica

    2010-09-01

    Over the past few years there has been an increasing acknowledgment that all knowledge is "sited knowledge." While place, mobility, and travel have become central issues in the history (and geography) of science, much of the discussion has nevertheless revolved around "formal scientific knowledge." This essay focuses on a specific type of popular "mobile" scientific knowledge making that emerged in the last decades of the nineteenth century: the educational cruise. In particular, it considers a series of voyages d'etude organized by the French scientific periodical Revue Générale des Sciences Pures et Appliquées between 1897 and 1914 that were open to the general public. It examines both the ways and the spaces in which knowledge was produced and the type of knowledge that was produced. PMID:21077549

  19. The End of Alchemy? The Repudiation and Persistence of Chrysopoeia at the Académie Royale des Sciences in the Eighteenth Century.

    PubMed

    Principe, Lawrence M

    2014-01-01

    The general abandonment of serious endeavor toward metallic transmutation represents a major development in the history of chemistry, yet its exact causes and timing remain unclear. This essay examines the fate of chrysopoeia at the eighteenth-century Académie Royale des Sciences. It reveals a long-standing tension between Académie chemists, who pursued transmutation, and administrators, who tried to suppress it. This tension provides background for Etienne-François Geoffroy's 1722 paper describing fraudulent practices around transmutation. Although transmutation seems to disappear after Geoffroy's paper, manuscripts reveal that most of the institution's chemists continued to pursue it privately until at least the 1760s, long after widely accepted dates for the "demise of alchemy" in learned circles. PMID:26103750

  20. Et pourquoi pas une education aux sciences qui aborde la participation des acteurs sociaux aux controverses sociotechniques?

    ERIC Educational Resources Information Center

    Pouliot, Chantal

    2012-01-01

    In this article we discuss research that was conducted as part of a project on citizen science education. We present the research and some of the results, and then take a position on the pertinence of examining, in science classes, questions on citizen participation in socio-technical debates and the roles and capacities of the social actors…

  1. Les effets du travail en equipe dans l'apprentissage par projets sur la motivation des etudiantes et des etudiants en formation des ingenieurs

    NASA Astrophysics Data System (ADS)

    Fernandez, Nicolas

    Les representants des secteurs industriels et les, milieux professionnels en Amerique du Nord reprochaient aux universites de former des ingenieurs avec peu d'experience pratique en resolution de problemes et en conception. Quelques programmes de genie ont alors mis en place le travail en equipe dans l'apprentissage par projets. Beaucoup d'ecrits font valoir les benefices de l'apprentissage par projets sur la motivation des etudiants. Or, ces benefices commencent a peine a faire l'objet de recherches visant a produire des donnees probantes a ce sujet. Les travaux sur la motivation en contexte d'apprentissage et les modeles theoriques developpes sont issus d'environnements d'apprentissage marques par l'enseignement magistral. Le modele de la valeur attendue de la tache (Eccles et Wigfield, 1995; Neuville, 2004) et le modele du systeme-groupe (St-Arnaud, 2008) ont ete retenus pour mesurer les effets du travail en equipe dans l'apprentissage par projets sur la motivation. La recherche visait aussi a approfondir et a nuancer la comprehension de la motivation des etudiants universitaires apprenant en contexte innovant. Les sujets constituent des etudiants (n=100) travaillant sur des projets d'integration au cours des trois sessions initiales du programme de genie mecanique d'une universite canadienne. L'analyse de regression multiple revele que les construits de la motivation expliquent un tiers de la variance de l'engagement academique dans la realisation du projet d'integration. Les perceptions de l' "expectancy", de la valeur intrinseque et utilitaire sont les determinants principaux de l'engagement des etudiants. L'analyse de variance multivariee a mesures repetees indique que la motivation des etudiants pour le travail sur les projets d'integration a augmente au cours des trois sessions initiales du parcours de formation. Finalement, malgre l'absence d'interaction significative entre les variables de motivation et de l'equipe, les reponses des sujets indiquent une amelioration du travail en equipe au terme des trois sessions. Mots cle: 1. apprentissage par projet; 2. projets d'integration; 3. travail en equipe; 4. motivation; 5. valeur attendue de la tache; 6. expectancy; 7. valeur intrinseque; 8. valeur utilitaire; 9. formation d'ingenieurs; 10. analyse quantitative.

  2. L'interdisciplinarite en sciences sociales pour l'etude du contact des langues (Interdisciplinarity in Social Sciences of the Study of the Relationships of Languages). Proceedings of a Colloquium of the International Center for Research on Bilingualism and the Institute for Interethnic and Intercultural Studies and Research (2nd, Quebec City, Quebec, Canada, October 1-5, 1984).

    ERIC Educational Resources Information Center

    Prujiner, Alain, Ed.

    Papers given at an international conference applying the social sciences to the study of the relationships of languages include the following: "Reseaux sociaux et comportements langagiers en milieu de contact des langues" ("Social Networks and Language Behaviors in a Language Contact Setting") by M. Blanc and J. Hamers, with commentary by R.…

  3. Building an interfaculty interprofessional education curriculum: what can we learn from the Université Laval experience?

    PubMed

    Milot, Élise; Dumont, Serge; Aubin, Michèle; Bourdeau, Gisèle; Azizah, Ginette Mbourou; Picard, Louise; St-Germain, Daphney

    2015-01-01

    Interprofessional education (IPE) is increasingly recognized as a means to improve practice in health and social care. However, to secure interprofessional learning, it is important to create occasions in prelicensure health and social services curriculum so that students can learn with, from and about each other. This paper presents the process behind the development and implementation of an IPE curriculum in 10 health and social sciences programs by a team of professors from the faculties of medicine, nursing sciences and social sciences at Université Laval in the province of Québec, Canada. The pedagogical approach, description of primary objectives and issues related to its implementation in the curriculum programs are also described and discussed. PMID:26261116

  4. Pourquoi entrer a l'Universite? L'Exemple d'une universite de lettres et sciences humaines

    NASA Astrophysics Data System (ADS)

    Canals, Valérie; Diebolt, Claude

    2001-11-01

    The large number of secondary school graduates entering higher education is transforming the nature of universities, particularly in literature and the humanities, by changing the relative numbers of students enrolled in different academic years. At the same time this influx is accompanied by a significant failure rate in the first academic year, calling into question the efficacy of the university system. A national issue with local repercussions, the struggle against failure in the first year is leading to much heart-searching among the universities, whose staff are trying hard to understand why certain students abandon their studies. The enquiry described in this article reveals the co-existence of two student populations: those who enter university as an active choice and those who do so by default. In the case of the first group, entry to university represents an investment for the future which must be carefully managed. In the second case it is a matter of going into higher education as a faute de mieux solution in an economic context in which work is scarce.

  5. Quelques Reflexions sur la Marginalite de l'Education des Adultes dans les Universites du Quebec

    ERIC Educational Resources Information Center

    Nadeau, Jean-Real

    1974-01-01

    The policies and attitudes of universities in the Province of Quebec toward adult education are examined as they relate to financing, admission, requirements, programs, and methods. (The article is written in French.) Available from: Extension Division, University of Saskatchewan, Saskatoon S7N OWO. (MW)

  6. Des Moines.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1988-01-01

    This document, intended for elementary students, contains articles and activities designed to acquaint young people with the history of Des Moines, Iowa. The articles are short, and new or difficult words are highlighted and defined for young readers. "The Raccoon River Indian Agency" discusses the archeological exploration of the indian…

  7. Science.

    ERIC Educational Resources Information Center

    Roach, Linda E., Ed.

    This document contains the following papers on science instruction and technology: "A 3-D Journey in Space: A New Visual Cognitive Adventure" (Yoav Yair, Rachel Mintz, and Shai Litvak); "Using Collaborative Inquiry and Interactive Technologies in an Environmental Science Project for Middle School Teachers: A Description and Analysis" (Patricia…

  8. Copernic: la piste des influences arabes

    NASA Astrophysics Data System (ADS)

    Khalatbari, A.; Bonnet-Bidaud, J. M.

    2004-10-01

    Copernic a-t-il connu le travail des astronomes du Moyen-Orient ? S'en est-il inspiré pour élaborer sa théorie de l'héliocentrisme ? C'est l'hypothèse avancée par certains historiens des sciences pour comprendre le génie de celui qui, le premier, a placé le Soleil au centre du monde. Enquête.

  9. Les Sciences Physiques À L'école Maternelle: Un Cadre Sociocognitif Pour La Construction Des Connaissances ET/OU LE Développement Des Activités Didactiques

    NASA Astrophysics Data System (ADS)

    Ravanis, Konstantinos

    2005-05-01

    NATURAL SCIENCES IN KINDERGARTEN: A SOCIO-COGNITIVE FRAMEWORK FOR LEARNING AND TEACHING - The present study presents a socio-cognitive framework for the construction of the scientific knowledge of natural phenomena among pre-school children and for the development of science activities at kindergarten. It involves elements from theories of social interaction; social psychology of development and cognitive functioning; and research in natural-science teaching methods which acknowledge the importance and fundamental role of social interaction in the development of cognitive operations and learning. The study also presents some of the more significant results of the research carried out on different aspects of this topic. The discussion unfolded here supports the hypothesis that the construction of natural-scientific knowledge at the pre-school age and corresponding scholastic activities are necessary and effective.

  10. Eine Beziehung seit 650 Jahren: Universität Wien und Kloster Melk - Katalog zur Sonderausstellung

    NASA Astrophysics Data System (ADS)

    Bruckmüller, Ernst; Niederkorn-Bruck, Meta; Beck, Paul G.; Deibl, Jakob; Deibl, Johannes; Denk, Ulrike; Ellegast, Burkard; Floßmann, Gerhard; Glaßner, Gottfried; Kalteis, Bernadette; Kowarik, Wilfried; Rotheneder, Martin

    2015-04-01

    University of Vienna was founded in 1365 and celebrates its 650 anniversary in 2015. Due to the university's anniversary, the Benedictine abbey of Melk, Austria presents an exhibition, depicting six and half centuries of university history and collaboration between the university as well as the abbey in all disciplines present at medieval universities. The publication describes the historic frame work as well as case-by-case descriptions of displayed manuscripts, prints and artifacts. Die Universität Wien wurde 1365 gegründet und feiert 2015 ihr 650jähriges Bestehen. Aus Anlass dieses Jubiläums präsentiert das Benediktiner Stift Melk eine Ausstellung, in der sechseinhalb Jahrhunderte Universistaetsgeschichte aufgearbeitet werden, sowie die Zusammenarbeit zwischen Universität und Abtei auf allen Themenbereichen, die an mittelalterlichen Universitäten angeboten wurden. Die Publikation bietet eine historische Zusammenfassung sowie eine Detailbeschreibung der ausgestellten Handschriften, Drucke sowie Gegenstände.

  11. Stufenweise Integration von eLearning an der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Pätzold, Sebastian; Graf, Stephan; Gergintchev, Ivan; Pongratz, Hans; Rathmayer, Sabine

    Der vorliegende Beitrag beschreibt als Best Practice Beispiel die stufenweise Integration eines Learning Management Systems (LMS) in die Infrastruktur von Information und Kommunikation (IuK) der Technischen Universität München (TUM). Dabei wird sowohl die Konsolidierung mehrfach angebotener Funktionalitäten und Dienste in den verschiedenen Portalen der Universität als auch die sukzessive Optimierung der Abläufe aufgezeigt. Gleichzeitig wird auf zukünftige weitere Entwicklungen hin zu einer vollständigen Integration der IuK, aber auch auf die Probleme in den unterschiedlichen Stadien der Entwicklung eingegangen.

  12. Innovating in teaching collaborative practice with a large student cohort at Université de Montréal.

    PubMed

    Vanier, Marie-Claude; Therriault, Pierre-Yves; Lebel, Paule; Nolin, France; Lefebvre, Hélène; Brault, Isabelle; Drouin, Eric; Fernandez, Nicolas

    2013-01-01

    Université de Montréal implemented an interprofessional education (IPE) curriculum on collaborative practice in a large cohort of students (>1,100) from 10 health sciences and psychosocial sciences training programs. It is made up of three one-credit undergraduate courses (CSS1900, CSS2900, CSS3900) spanning the first 3 years of training. The course content and activities aim for development of the six competency domains identified by the Canadian Interprofessional Health Collaborative. This paper describes the IPE curriculum and highlights the features contributing to its success and originality. Among main success key factors were: administrative cooperation among participating faculties, educators eager to develop innovative approaches, extensive use of clinical situations conducive to knowledge and skill application, strong logistic support, close cooperation with health care delivery organizations, and partnership between clinicians and patients. A distinguishing feature of this IPE curriculum is the concept of partnership in care between the patient and caregivers. Patients' representatives were involved in course planning, and patients were trained to become patients-as-trainers and cofacilitate interprofessional discussion workshops. They give feedback to students regarding integration and application of the patient partnership concept from a patient's point of view. PMID:24326925

  13. Effets des electrons secondaires sur l'ADN

    NASA Astrophysics Data System (ADS)

    Boudaiffa, Badia

    Les interactions des electrons de basse energie (EBE) representent un element important en sciences des radiations, particulierement, les sequences se produisant immediatement apres l'interaction de la radiation ionisante avec le milieu biologique. Il est bien connu que lorsque ces radiations deposent leur energie dans la cellule, elles produisent un grand nombre d'electrons secondaires (4 x 104/MeV), qui sont crees le long de la trace avec des energies cinetiques initiales bien inferieures a 20 eV. Cependant, il n'y a jamais eu de mesures directes demontrant l'interaction de ces electrons de tres basse energie avec l'ADN, du principalement aux difficultes experimentales imposees par la complexite du milieu biologique. Dans notre laboratoire, les dernieres annees ont ete consacrees a l'etude des phenomenes fondamentaux induits par impact des EBE sur differentes molecules simples (e.g., N2, CO, O2, H2O, NO, C2H 4, C6H6, C2H12) et quelques molecules complexes dans leur phase solide. D'autres travaux effectues recemment sur des bases de l'ADN et des oligonucleotides ont montre que les EBE produisent des bris moleculaires sur les biomolecules. Ces travaux nous ont permis d'elaborer des techniques pour mettre en evidence et comprendre les interactions fondamentales des EBE avec des molecules d'interet biologique, afin d'atteindre notre objectif majeur d'etudier l'effet direct de ces particules sur la molecule d'ADN. Les techniques de sciences des surfaces developpees et utilisees dans les etudes precitees peuvent etre etendues et combinees avec des methodes classiques de biologie pour etudier les dommages de l'ADN induits par l'impact des EBE. Nos experiences ont montre l'efficacite des electrons de 3--20 eV a induire des coupures simple et double brins dans l'ADN. Pour des energies inferieures a 15 eV, ces coupures sont induites par la localisation temporaire d'un electron sur une unite moleculaire de l'ADN, ce qui engendre la formation d'un ion negatif transitoire dans un etat electronique dissociatif, cette localisation est suivie d'une fragmentation. A plus haute energie, la dissociation dipolaire (i.e., la formation simultanee d'un ion positif et negatif) et l'ionisation jouent un role important dans le dommage de l'ADN. L'ensemble de nos resultats permet d'expliquer les mecanismes de degradation de l'ADN par les EBE et d'obtenir des sections efficaces effectives des differents types de dommages.

  14. La modelisation mathematique dans l'enseignement de la chimie des gaz a des eleves de la cinquieme annee du secondaire

    NASA Astrophysics Data System (ADS)

    Gauthier, Diane

    Les problemes d'enseignement de la chimie des gaz parfaits sont donc importants. Si plusieurs etudes ont ete realisees dans le but d'identifier et d'interpreter ces problemes, aucune recherche, a notre connaissance, n'a ete realisee sur l'enseignement des lois sur les gaz parfaits. Notre recherche sur l'enseignement est donc pionniere. Elle a pour objectif general de construire et d'analyser une sequence d'enseignement de la chimie des gaz comportant diverses situations de modelisation mathematique des conduites des gaz. Les principaux objectifs specifiques sont les suivants: (1) identifier et caracteriser les situations qui provoquent une evolution des conceptions naives des eleves, evolution vers des connaissances plus adequate sur les gaz; (2) identifier et caractEriser les situations qui provoquent une evolution des connaissances mathematiques des eleves leur permettant d'interpreter convenablement les resultats des experiences, d'eprouver leurs conceptions, de donner un sens aux notions et aux relations impliquees dans les lois des gaz parfaits, lois de Boyle-Mariotte et Gay-Lussac. Une sequence d'enseignement comportant huit situations est d'eleves de secondaire V. La construction de ces situations est orientee par les recherches sur les conceptions naives des eleves, par les etudes sur l'evolution historique des conceptions sur les gaz et des pratiques scientifiques, ainsi que par les etudes theoriques et empiriques realisees en didactique des sciences et des mathematiques. La methodologie de l'ingenierie didactique (Artigue, 1998) qui constitue une application de la theorie des situations didactiques (Brousseau, 1986) est utilisee dans la construction et l'analyse des situations d'enseignement. Une analyse a priori de chacune des situations d'enseignement est effectuee; elle a pour but dexpliquer les choix des taches qui font partie des situations et de preciser la gestion didactique des situations. Diverses situations d'enseignement de la chimie ont ainsi ete construites. L'analyse a posteriori des situations, analyse des interactions didactiques lors du deroulement en classe de ces situations, est confrontee a l'analyse a priori realisee lors de la construction de ces situations. La pertinence de ces situations est ainsi examinee, en regard des objectifs de la recherche. (Abstract shortened by UMI.)

  15. Comprendre le processus d'adaptation des demarches d'enseignement en classe de sciences et technologies a l'ecole secondaire: Analyse des besoins percus par les personnes enseignantes en milieu defavorise

    NASA Astrophysics Data System (ADS)

    Houde, Sylvie

    Since the implementation of the latest reform in the education programs of Quebec, the adaptation of teaching has taken on an important place in the concerns of all actors in education. However, this adjustment towards the adoption of teaching practices that require more participation on the part of the pupil is not accomplished so easily, particularly in the field of science and technology (ST). In order to gain a better understanding of these processes of adaptation, it is opportune to question ourselves on the factors and dynamics of interest at stake, especially in disadvantaged environments. Such environments are faced with situations where other difficulties coexist: integration of pupils, lack of interest, problems in classroom management, multi-ethnicity, etc. As a result, such difficulties give rise to particular limitations, expressed in the form of needs, by pupils and teachers, likely to have a restrictive effect on the adaptation of teaching practices. Accordingly, our research focuses on the needs perceived by teachers in high school ST classrooms in disadvantaged school environments, since they present a privileged means to better understand the processes involved in the adaptation of practices. The adoption of an ecosystemic perspective, centered on these needs and their contribution towards the dynamics of decision-making, enabled us to better apprehend the complexity of these processes in ST classrooms. We were able to identify the needs perceived by teachers by following the methodology of conceptanalysis of needs, and by combining focus groups with the DRAP software. The results account for the large variety of needs to be considered in the equation of adaptation of teaching practices. These needs generally belong to the classroom system (microsystem). For pupils, they are mainly cognitive needs, but for teachers, they pertain to organization and structure. The influence of these needs on the adaptation processes depends on the interpretation by teachers of teaching situations, so much so that a same need can at times be assumed as negative pressure, generating obstacles, or at other times as a positive impulse, facilitating adaptation. Keywords: teaching practices; science and technology education; high school education; adaptation processes; needs assessment; disadvantaged environments.

  16. Naturwissenschaft und Bildung: Betrachtungen uber die Aktualitat des Genetischen Lernens (Natural Science and Education - Reflections on the Pertinence of Genetic Learning).

    ERIC Educational Resources Information Center

    Ullrich, Heiner

    2000-01-01

    States that the educational mission of instruction in natural science is still not clearly defined. Explains that the unclear mission is revealed by the situation in instruction in physics today as well as by the scholastic achievement in this field. (CMK)

  17. Profile of the International Work of Canadian Universities=Profil de la collaboration internationale des universites Canadiennes.

    ERIC Educational Resources Information Center

    Goldstone, Jennifer, Ed.; Gibbs, Darlene, Ed.

    This directory describes international cooperation programs at 66 Canadian colleges and universities. Listed alphabetically, each institution briefly summarizes its international initiatives, provides information on the history and administrative structure of the international activities, includes a list of programs, and provides contact…

  18. Developpement et evaluation d'un environnement informatise d'apprentissage pour faciliter l'integration des sciences et de la technologie

    NASA Astrophysics Data System (ADS)

    Saliba, Marie-Therese

    2011-12-01

    Through this research we will fully assess the benefits brought by the ExAO (Computer Assisted Experimentation) in school laboratories of science and technology in Lebanon. We would also like to mention its contribution in a tangible way in laboratory research of Pedagogic Robotic from Montreal University, particularly in the development of ExAO mulaboratory. We wanted to test the capabilities of the ExAO, its use in the classroom such as: 1. A replacement of a traditional laboratory in the use of the experimental method. 2. A scientific investigation tool. 3. An integration tool of experimental sciences and mathematics. 4. An integration tool of experimental sciences, mathematics and technology in the technoscientific learning. To do so, we have mobilized 13 group classes, designated teachers to experiment themselves along with their students in order to assess, in a more realistic way, the benefits of implementing this micro computer laboratory at school. Different testing, evaluated using the results of learning activities undertaken by students, their responses to a questionnaire and feedback from teachers, show that: 1. The replacement of a traditional laboratory with an ExAO mulaboratory does not seem to pose problem, expected that students have adapted to it in only ten minutes, indicating that the speed with which data were graphed was more productive. 2. In order to investigate a physical phenomenon, the usability of the tutorial associated with the ability to amplify the phenomenon before its graph representation, has allowed students to design and implement quickly and independently an experiment to verify their prediction. 3. The integration of mathematics into an experimental approach can quickly grasp the phenomenon. In addition, it gives more autonomy and a meaning to the graphs and algebraic representations allowing to use them as a cognitive tool to interpret this phenomenon. 4. The approach made by the students to design and construct a technological object, showed that this activity was easily carried out by the use of universal sensors, amplifiers to offset the graphical modeling tool, and the tutorial ability to transform any measured variable by another variable (for instance, the resistance variation in temperature change, ...). This educational activity shows that students had no difficulty integrating in a single learning activity the mathematics, experimental sciences and technology, in order to design and implement a functional piece of technology. The ExAO mulaboratory, by offering new educational opportunities, such as the ability to design, produce and validate a technological object, in order to do so, new capacities to boost measures, modeling physical phenomena, developing new sensors, is an important addition to the experiments being conducted in ExAO. Keywords: ExAO, teaching, integration, Lebanese schools.

  19. Register of Education and Training Activities in Librarianship, Information Science and Archives = Inventaire des activites de formation dans le domaine de la bibliotheconomie, des sciences de l'information et de l'archivistique = Inventario de las actividades de formacion en la esfera de la bibliotecologia, las ciencias de la informacion y la archivologia.

    ERIC Educational Resources Information Center

    de Grolier, Eric, Comp.

    This register provides information on information science, librarianship, documentation, and archival science training activities conducted outside regular university courses organized by specialized schools. Based on a December 1980 UNESCO questionnaire survey, the register includes seminars, refresher courses, continuing education courses, and…

  20. Register of Education and Training Activities in Librarianship, Information Science and Archives = Inventaire des activites de formation dans le domaine de la bibliotheconomie, des sciences de l'information et de l'archivistique = Inventario de las actividades de formacion en la esfera de la bibliotecologia, las ciencias de la informacion y la archivologia.

    ERIC Educational Resources Information Center

    de Grolier, Eric, Comp.

    This register provides information on information science, librarianship, documentation, and archival science training activities conducted outside regular university courses organized by specialized schools. Based on a December 1980 UNESCO questionnaire survey, the register includes seminars, refresher courses, continuing education courses, and

  1. INISTE. Directory of the International Network for Information in Science and Technology Education = Repertoire du reseau international d'information concernant l'enseignement des sciences et de la technologie.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France). Div. of Science, Technical and Environmental Education.

    The objectives of this directory are to provide information which will strengthen regional and international cooperation and research in the field of science and technology education, and to promote greater exchange of ideas and information using new information technologies between institutions. This directory is the first issue of the…

  2. Formation et Evolution des Quasars et Contraintes cosmologiques

    NASA Astrophysics Data System (ADS)

    Hatziminaoglou, Evanthia

    2000-06-01

    Cette thèse porte sur l'étude de l'évolution des quasars. Elle en aborde certains aspects théoriques et observationnels, ainsi que la construction des grands échantillons de quasars dans le but à long terme de combiner le tout dans un test cosmologique géométrique pour déterminer les valeurs des paramètres cosmologiques Omega et Lambda. Les paramètres cosmologiques Omegaspan>et Lambdaspan>décrivent la géométrie globale de l'Univers. En faisant des hypothèses raisonnables sur la distribution spatiale et l'évolution des objets astrophysiques (galaxies, amas des galaxies, quasars), on peut déterminer les valeurs de ces paramètres qui sont cohérentes avec ces hypothèses. Les tests cosmologiques traditionnels ont besoin de ''chandelles standards'', objets dont les propriétés intrinsèques sont indépendantes des distances. De tels objets sont probablement fictifs. Néanmoins, certains de ces tests cosmologiques peuvent être adaptés si l'évolution individuelle, ou au moins l'évolution statistique d'une population d'objets est connue. La question de la nature de l'évolution des quasars a très vite été posée et des réponses ''phénoménologiques'' ont d'abord été données. Ces réponses ne faisaient que donner une forme mathématique à l'évolution mais n'expliquaient rien de la physique duphénomène. Les premières tentatives de construction d'un modèle physique, liées au processus d'accrétion sur un trou noir et à la théorie de la formation de l'Univers ont commencé à la fin des années 80. Depuis, des dizaines de modèles tentent d'expliquer les observations, qui sont les résultats de l'étude d'objets de plus en plus nombreux. Au cours de cette thèse, le test V/Vmax a été appliqué sur l'échantillon du Large Bright Quasar Survey en montrant 1) que l'échantillon était biaisé à cause des critères de sélection et 2) que la (simple) loi de Pure Evolution en Luminosité n'était pas une bonne approximation à tout redshift mais qu'elle décrivait assez bien l'évolution des quasars jusqu'à z ~2 . Pour ces deux raisons, une méthode de sélection de candidats quasars efficace à tout redshift a été mise au point et des modèles théoriques de formation et évolution des quasars ont été développés. Cette technique de sélection de candidats quasars, développée pour les besoins du projet spectroscopique VIRMOS , est basée sur la méthode des redshifts photométriques, qui consiste à comparer la distribution d'énergie spectrale observée (photométrie dans plusieurs filtres) avec celle calculée pour des spectres-modèles. Dans le cas de la sélection de candidats quasars, la photométrie des objets (en principe ponctuels mais ceci n'est pas nécessaire) est comparée à des spectres simulés de quasars et à une série de spectres réels d'étoiles. Le meilleur ajustement (Chi2 minimum) permet alors de caractériser un objet comme candidat étoile ou candidat quasar. Cette méthode peut, en principe, fournir des catalogues qui ne sont pas biaisés en redshift et qui ont une grande complétude. En même temps, une estimation du redshift (photométrique) des candidats quasars est donnée, en dirigeant ainsi la spectroscopie vers l'optique ou l'infrarouge. Dans la partie théorique, des modèles de formation et d'évolution de quasars ont été développés ou sont en cours de développement. Depuis peu de temps des indices de l'existence de trous noirs plus ou moins massifs au centre de beaucoup de galaxies, même normales, se sont accumulés. D'une part, un modèle analytique est en cours de développement en collaboration avec l'Université de Barcelona. Ce modèle a initialement été développé pour étudier la formation et évolution des galaxies. Au cours de cette thèse, nous avons contacté l'équipe de E. Salvador-Solé et je leur ai proposé d'incorporer des Trous Noirs Massifs dans les galaxies et d'étudier, ainsi, la naissance et l'évolution des quasars. Un modèle d'accrétion autour d'un trou noir massif a alors été implementé dans le code d'évolution des galaxies. Ce modèle sera opérationnel au début de l'automne et fera des prédictions sur l'évolution de la fonction de luminosité des quasars, leur connexion aux galaxies Seyfert et aux starbursts, leur durée de vie et leur pourcentage dans les différent types de galaxies. Le grand intérêt du modèle sera la sortie, en même temps, d'une fonction de luminosité pour les quasars et de l'histoire du taux de formation stellaire, deux phénomènes qui pourront être étudiés simultanément. Par ailleurs, j'ai développé un modèle analytique basé sur les instabilités des disques d'accrétion, en collaboration avec A. Siemiginowska et M. Elvis du CfA, Cambridge, USA, donnant des résultats satisfaisants sur la fonction de luminosité des quasars à grand redshift. L'hypothèse d'une relation linéaire entre les masses du trou noir central et du halo de matière noire qui l'héberge a été rejetée. Le même modèle impose des contraintes sur la valeur de l'exposant du spectre de puissance primordial, P(k), qui décrit les fluctuations primordiales.

  3. Amputation des quatre membres

    PubMed Central

    Feruzi, Maruis Kitembo; Milindi, Cédrick Sangwa; Zabibu, Mireille Kakinga; Mulefu, Jules Panda; Katombe, Francois Tshilombo

    2014-01-01

    Les auteurs présentent les cas d'amputation des quatre membres réalisée chez trois patients différents. Ce sont des amputations réalisées pour chaque patient au cours d'une seule hospitalisation et en un seul temps opératoire. Deux patients pour gangrène sèche infectée et un pour amputation traumatique des quatre membres. L'amputation d'urgence a été pratiquée en premier temps suivie de remodelage des moignons d'amputation en second temps. L’évolution de tous les patients a été bonne. PMID:25469177

  4. Le?Ons Sur Les Ondes De Gravit Des Fluides Incompressibles

    NASA Astrophysics Data System (ADS)

    van den Dungen, F. H.

    Le 3 Janvier 1814 au moment o les Allis franchissant le Rhin allaient entamer la campagne de France, la classe des Sciences de l'Institut de France proposait comme sujet du grand prix de mathmatique dcerner en Janvier 1816 la question suivante: "La thorie de la propagation des ondes la surface d'un fluide pesant d'une profondeur infinie".

  5. L’opinion des étudiants en médecine de Québec sur les punitions corporelles

    PubMed Central

    Labbé, Jean; Laflamme, Nathalie; Makosso-Kallyth, Sun

    2012-01-01

    OBJECTIF : L’objectif de la présente étude est de décrire l’opinion des étudiants en médecine de l’Université Laval sur le sujet controversé des punitions corporelles envers les enfants. MÉTHODOLOGIE : Un sondage a été réalisé auprès des étudiants en quatrième année de médecine de l’Université Laval pendant cinq années consécutives, soit de l’année scolaire 2006–2007 jusqu’à celle de 2010–2011 inclusivement, à l’occasion d’un séminaire portant sur la maltraitance envers les enfants. RÉSULTATS : Sur les 712 étudiants interrogés, 74 % étaient de sexe féminin et 91 % étaient âgés de moins de 30 ans. Concernant les punitions corporelles envers les enfants, 22 % des répondants s’y sont déclarés favorables. Plus de garçons que de filles se sont prononcés en faveur de cette pratique disciplinaire, soit 31 % des garçons par rapport à 18 % des filles respectivement (RC rajusté = 2,2, IC 95 % :1,4 à 3,4; p=0,0003). Près de 36 % des étudiants ayant eu des punitions corporelles y étaient favorables, comparativement à seulement 4 % de ceux qui n’avaient pas connu cette forme de discipline (RC rajusté = 16,5, IC 95 % :8,6 à 31,4; p<0,0001). Parmi ceux qui ont mentionné avoir été victimes d’abus physique, 25 % se sont déclarés en faveur de cette pratique, ce qui est similaire au 21 % observés chez ceux qui n’en ont pas été victimes (p=0,52). CONCLUSION : Alors que plusieurs organismes médicaux se sont prononcés contre l’utilisation des punitions corporelles, plus d’un futur médecin sur cinq à Québec se déclare favorable à cette méthode disciplinaire et pourrait influencer la conduite des parents en ce sens. PMID:24179417

  6. Cartographie des disques

    NASA Astrophysics Data System (ADS)

    Hameury, Jean-Marie

    2001-01-01

    Two techniques are frequently used to produce images of the accretion disc in an eclipsing binary: eclipse mapping and Doppler tomography. From the light curve, one can deduce the radial distribution of the effective temperature, assuming axial symmetry. On the other hand, from the variation of the line profile one can reconstruct an image in the velocity space, which can be converted into a real image if one knows the kinematics of the system. Deux techniques sont couramment utilisées pour obtenir des images des disques dans les systèmes binaires à éclipses. En utilisant la courbe de lumière, on peut remonter à la distribution radiale de la brillance de surface, en supposant que celle-ci a une symètrie axiale. D'autre part, les profils de raies renseignent sur la distribution de vitesse des régions émissives leur variation temporelle permet de réaliser une image dans l'espace des vitesses, que l'on peut ensuite transformer en carte dans l'espace (x,y) si on connaît la cinématique du système.

  7. Injectabilite des coulis de ciment dans des milieux fissures

    NASA Astrophysics Data System (ADS)

    Mnif, Thameur

    Le travail presente ici est un bilan du travaux de recherche effectues sur l'injectabilite des coulis de ciment dans lu milieux fissures. Un certain nombre de coulis a base de ciment Portland et microfin ont ete selectionnes afin de caracteriser leur capacite a penetrer des milieux fissures. Une partie des essais a ete menee en laboratoire. L'etude rheologique des differents melanges a permis de tester l'influence de l'ajout de superplastifiant et/ou de fumee de silice sur la distribution granulometrique des coulis et par consequent sur leur capacite a injecter des colonnes de sable simulant un milieu fissure donne. La classe granulometrique d'un coulis, sa stabilite et sa fluidite sont apparus comme les trois facteurs principaux pour la reussite d'une injection. Un facteur de finesse a ete defini au cours de cette etude: base sur la classe granulometrique du ciment et sa stabilite, il peut entrer dans la formulation theorique du debit d'injection avant application sur chantier. La deuxieme et derniere partie de l'etude presente les resultats de deux projets de recherche sur l'injection realises sur chantier. L'injection de dalles de beton fissurees a permis le suivi de l'evolution des pressions avec la distance au point d'injection. L'injection de murs de maconnerie a caractere historique a montre l'importance de la definition de criteres de performance des coulis a utiliser pour traiter un milieu donne et pour un objectif donne. Plusieurs melanges peuvent ainsi etre predefinis et mis a disposition sur le chantier. La complementarite des ciments traditionnels et des ciments microfins devient alors un atout important. Le choix d'utilisation de ces melanges est fonction du terrain rencontre. En conclusion, cette recherche etablit une methodologie pour la selection des coulis a base de ciment et des pressions d'injection en fonction de l'ouverture des fissures ou joints de construction.

  8. Prévalence et caractéristiques de l'automédication chez les étudiants de 18 à 35 ans résidant au Campus de la Kasapa de l'Université de Lubumbashi

    PubMed Central

    Chiribagula, Valentin Bashige; Mboni, Henry Manya; Amuri, Salvius Bakari; kamulete, Grégoire Sangwa; Byanga, Joh Kahumba; Duez, Pierre; Simbi, Jean Baptiste Lumbu

    2015-01-01

    Introduction L'automédication est devenue un phénomène émergeant et menaçant de plus en plus la santé publique. La présente étude objective de déterminer la prévalence et les caractéristiques dans le campus Universitaire Kasapa de l'Université de Lubumbashi. Méthodes L'interview indirecte a servi à la collecte des données qui ont été traitées par le logiciel Graphpad version 5. Résultats De 515 étudiants consultés, l'automédication présente une prévalence de 99%, une partie des sujets l'ayant débutée à l'adolescence (35%). Des répondants, 78,8% reconnaissent que l'automédication peut conduire à un échec thérapeutique et que des erreurs de dose, un traitement inadapté, des effets secondaires et des erreurs diagnostiques sont plausibles. Cette pratique est acceptée pour autant qu'elle permette de prendre en charge des maladies ou symptômes présumés bénins et connus avec pour avantages, discrétion et économie de temps et d'argent. La malaria (82,4%), la fièvre (65,5%), les maux de tête (65,5%) en constituent les trois premières causes. L'amoxicilline (98,2%), le paracétamol (97,5%), l'acide ascorbique (91,6%) et la quinine (79,4%) sont les quatre premiers médicaments les plus consommés. L'association la plus utilisée est paracétamol’ vitamine(s) (88,8%) et la plus aberrante amoxycilline -Erytromycine (25,5%). Le comprimé (37%) constitue la forme la plus utilisée. La plupart des sujets (84,9%), recourent aux plantes médicinales. Conclusion Dans ce milieu, il existe une forte prévalence de l'automédication largement dans un but antipalustre avec quelques abus. PMID:26327945

  9. IntegraTUM Teilprojekt E-Mail: Aufbau eines mandantenfähigen Groupware-Services und seine Integration in Identity Management und E-Mail Infrastruktur der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Diehn, Max

    Die E-Mail-Infrastruktur an der Technischen Universität München (TUM) ist historisch bedingt sehr heterogen und komplex. Viele Einrichtungen müssen wertvolle Arbeitskraft auf die Administration eigener Mailserver verwenden. Auf der anderen Seite wird bei einigen Einrichtungen der Ruf nach Groupware-Funktionalitäten wie z.B. gemeinsame Kalender immer lauter. Das Teilprojekt E-Mail stellt einen zentralen Mail- und Groupware-Service bereit, der den Einrichtungen ermöglichen soll, den Betrieb eigener Server und zugehöriger Systeme (etwa lokaler Benutzerverwaltungen) für diesen Zweck aufzugeben und diese Dienste an das Teilprojekt E-Mail zu migrieren, ohne ihre Verwaltungshoheit oder ihre Maildomains aufgeben zu müssen. Dieser Service versteht sich als eine Ergänzung zur bestehenden Grundversorgung der TUM mit den Maildiensten des myTUM-Mailers, ist mandantenfähig aufgebaut und kann daher künftig neben der TUM auch weiteren Organisationen im Münchner Wissenschaftsnetz zur Verfügung gestellt werden.

  10. Grundlagen des Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Mayer, Jörg; Blum, Janaki; Wintermantel, Erich

    Die Organtransplantation stellt eine verbreitete Therapie dar, um bei krankheitsoder unfallbedingter Schädigung eines Organs die Gesamtheit seiner Funktionen wieder herzustellen, indem es durch ein Spenderorgan ersetzt wird. Organtransplantationen werden für die Leber, die Niere, die Lunge, das Herz oder bei schweren grossflächigen Verbrennungen der Haut vorgenommen. Der grosse apparative, personelle und logistische Aufwand und die Risiken der Transplantationschirurgie (Abstossungsreaktionen) sowie die mangelnde Verfügbarkeit von immunologisch kompatiblen Spenderorganen führen jedoch dazu, dass der Bedarf an Organtransplantaten nur zu einem sehr geringen Teil gedeckt werden kann. Sind Spenderorgane nicht verfügbar, können in einzelnen Fällen lebenswichtige Teilfunktionen, wie beispielsweise die Filtrationsfunktion der Niere durch die Blutreinigung mittels Dialyse ersetzt oder, bei mangelnder Funktion der Bauchspeicheldrüse (Diabetes), durch die Verabreichung von Insulin ein normaler Zustand des Gesamtorganismus auch über Jahre hinweg erhalten werden. Bei der notwendigen lebenslangen Anwendung apparativer oder medikamentöser Therapie können für den Patienten jedoch häufig schwerwiegende, möglicherweise lebensverkürzende Nebenwirkungen entstehen. Daher werden in der Forschung Alternativen gesucht, um die Funktionen des ausgefallenen Organs durch die Implantation von Zellen oder in vitro gezüchteten Geweben möglichst umfassend wieder herzustellen. Dies erfordert biologisch aktive Implantate, welche die für den Stoffwechsel des Organs wichtigen Zellen enthalten und einen organtypischen Stoffwechsel entfalten.

  11. Directory of Personnel, Canadian Association of Departments of Extension and Summer Schools. Annuaire du Personnel, Association des Services d'Education des Adultes et Ecoles d'Ete des Universites du Canada.

    ERIC Educational Resources Information Center

    British Columbia Univ., Vancouver. Dept. of Univ. Extension.

    This bilingual directory of the Canadian Association of Departments of Extension and Summer Schools (CADESS) lists CADESS administrators and faculty, by subject area or division and alphabetically by institutions, associated with the Memorial University of Newfoundland, the Banff School of Fine Arts and Centre for Continuing Education, Saint…

  12. Allgemeine Padagogik und Padagogische Bildung: Erziehungs- und bildungswissenschaftliche Mindestanforderungen an das Studium des Unterrichtsfaches Padagogik (Education Theory and Pedagogical Expertise: Minimum Standards in Educational Science for Future Teacher of Pedagogics).

    ERIC Educational Resources Information Center

    Bernhard, Armin

    2001-01-01

    Explores the thesis that educational theory plays a crucial role in training teachers in the area of pedagogics. Stresses references to the discipline of educational science and advocates training pedagogics teachers and instruction in pedagogics tuned to the principles of a science orientation. (CMK)

  13. La diffraction des neutrons et des rayons X pour l'étude structurale des liquides et des verres

    NASA Astrophysics Data System (ADS)

    Fischer, H. E.; Salmon, P. S.; Barnes, A. C.

    2003-02-01

    La compréhension de mainte propriété physique d'un verre ou d'un liquide nécessite la connaissance des facteurs de structure partiels (PSFs) qui décrivent chacun la distribution d'une espèce atomique autour d'une autre. La technique de diffraction des neutrons avec substitution isotopique (NDIS) [1,2,3], ayant bien réussi a déterminer les PSFs de certains composés [4,5], est pourtant restreinte aux isotopes présentant un contraste suffisant en longueur de diffusion. D'un autre cote, la technique de diffusion anomale des rayons X (AXS ou AXD) [6] permet de faire varier la longueur de diffusion d'une espèce atomique pourvu que son énergie d'absorption soit à la fois accessible et suffisamment élevée pour donner un assez grand transfert du moment. La combinaison des techniques de diffraction des neutrons (avec ou sans substitution isotopique) et de diffraction des rayons X (avec ou sans diffusion anomale) peut donc permettre d'obtenir un meilleur contraste en longueurs de diffusion pour un système donné, mais exige une analyse de données plus soignée pour pouvoir bien tenir compte des erreurs systématiques qui sont différentes pour les 2 techniques [7]. Pour les atomes ayant des distributions électroniques quasi-sphériques, e.g. dans le cas d'un alliage liquide, la combinaison des techniques de NDIS et de diffraction des rayons X s'est déjà montrée très avantageuse pour la détermination des PSFs [8,9]. Dans le cas des verres ayant d'importantes liaisons covalentes, l'effective combinaison des 2 techniques peut être moins directe mais facilitée lorsqu'il s'agit des atomes de grand Z [10,11]. Nous présentons ici un sommaire du méthode et quelques exemples des résultats.

  14. Restauration adaptative des contours par une approche inspiree de la prediction des performances

    NASA Astrophysics Data System (ADS)

    Rousseau, Kami

    En teledetection, les cartes de contours peuvent servir, entre autres choses, a la restitution geometrique, a la recherche d'elements lineaires, ainsi qu'a la segmentation. La creation de ces cartes est faite relativement tot dans la chaine de traitements d'une image. Pour assurer la qualite des operations subsequentes, il faut veiller a obtenir une carte de contours precise. Notre problematique est de savoir s'il est possible de diminuer la perte de temps liee au choix d'algorithme et de parametre en corrigeant automatiquement la carte de contours. Nous concentrerons donc nos efforts sur le developpement d'une methode de detection/restauration de contours adaptative. Notre methode s'inspire d'une technique de prediction des performances d'algorithmes de bas niveau. Elle consiste a integrer un traitement par reseau de neurones a une methode " classique " de detection de contours. Plus precisement, nous proposons de combiner la carte de performances avec la carte de gradient pour permettre des decisions plus exactes. La presente etude a permis de developper un logiciel comprenant un reseau de neurones entraine pour predire la presence de contours. Ce reseau de neurones permet d'ameliorer les decisions de detecteurs de contours, en reduisant le nombre de pixels de fausses alarmes et de contours manques. La premiere etape de ce travail consiste en une methode d'evaluation de performance pour les cartes de contours. Une fois ce choix effectue, il devient possible de comparer les cartes entre elles. Il est donc plus aise de determiner, pour chaque image, la meilleure detection de contours. La revue de la litterature realisee simultanement a permis de faire un choix d'un groupe d'indicateurs prometteurs pour la restauration de contours. Ces derniers ont servi a la calibration et a l'entrainement d'un reseau de neurones pour modeliser les contours. Par la suite, l'information fournie par ce reseau a ete combinee par multiplication arithmetique avec les cartes d'amplitudes de detecteurs " classiques " afin de fournir de nouvelles cartes d'amplitude du gradient. Le seuillage de ces contours donne des cartes de contours " optimisees ". Sur les images aeroportees du jeu de donnees South Florida, la mediane des mesures-F de la pour l'algorithme de Sobel passe de 51,3 % avant la fusion a 56,4 % apres. La mediane des mesures-F pour l'algorithme de Kirsch ameliore est de 56,3 % et celle de Frei-Chen ameliore est de 56,3 %. Pour l'algorithme de Sobel avec seuillage adaptatif, la mesure-F mediane est de 52,3 % avant fusion et de 57,2 % apres fusion. En guise de comparaison, la mesure-F mediane pour le detecteur de Moon, mathematiquement optimal pour contours de type " rampe ", est de 53,3 % et celle de l'algorithme de Canny, est de 61,1 %. L'applicabilite de notre algorithme se limite aux images qui, apres filtrage, ont un rapport signal sur bruit superieur ou egal a 20. Sur les photos au sol du jeu de donnees de South Florida, les resultats sont comparables a ceux obtenus sur les images aeroportees. Par contre, sur le jeu de donnees de Berkeley, les resultats n'ont pas ete concluants. Sur une imagette IKONOS du campus de l'Universite de Sherbrooke, pour l'algorithme de Sobel, la mesure-F est de 45,7 % +/-0,9 % avant la fusion et de 50,8 % apres. Sur une imagette IKONOS de l'Agence Spatiale Canadienne, pour l'algorithme de Sobel avec seuillage adaptatif, la mesure-F est de 35,4 % +/-0,9 % avant la fusion et de 42,2 % apres. Sur cette meme image, l'algorithme de Argyle (Canny sans post-traitement) a une mesure-F de 35,1 % +/-0,9 % avant fusion et de 39,5 % apres. Nos travaux ont permis d'ameliorer la banque d'indicateurs de Chalmond, rendant possible le pretraitement avant le seuillage de la carte de gradient. A chaque etape, nous proposons un choix de parametres permettant d'utiliser efficacement la methode proposee. Les contours corriges sont plus fins, plus complets et mieux localises que les contours originaux. Une etude de sensibilite a ete effectuee et permet de mieux comprendre la contribution de chaque indicateur. L'efficacite de l'outil developpe est comparable a celle d'autres methodes de detection de contours et en fait un choix interessant pour la detection de contours. Les differences de qualite observees entre notre methode et celle de Canny semble etre dues a l'utilisation, ou non, de post-traitements. Grace au logiciel developpe, il est possible de reutiliser la methodologie; cette derniere a permis d'operationnaliser la methode proposee. La possibilite de reutiliser le filtre, sans reentrainement est interessante. La simplicite du parametrage lors de l'utilisation est aussi un avantage. Ces deux facteurs repondent a un besoin de reduire le temps d'utilisation du logiciel. Mots-cles: detection de signal adaptative, caracterisation des performances, reseaux de neurones, imagerie panchromatique, analyse de contours.

  15. Les Applications Therapeutiques Des Lasers

    NASA Astrophysics Data System (ADS)

    Brunetaud, J. M.; Mordon, S.; Bourez, J.; Mosquet, L.; Moschetto, Y.

    1984-03-01

    C'est de tres loin le mecanisme predominant dans les applications therapeutiques du laser. En concentrant le flux lumineux sur une surface redui-te, le laser chauffe localement les tissus qui se retractent (coagulation) pour etre elimines ensuite (detersion) ; si on chauffe plus intensement, les tissus peuvent etre volatilises. La coagulation est utilisee soit pour detruire de petits phenomenes tumoraux qui seront elimines lors du processus de detersion, soit pour arreter une hemorragie (hemo-stase) ; dans ce cas la retraction thermique des tissus va provoquer la fermeture de la lumiere des vaisseaux qui seront secondairement obliteres par des caillots formes sur place (thrombose). Par volatilisation it est possible de detruire des phenomenes tumoraux plus importants que ceux at-teints lors d'une simple coagulation. Si la zone volatilisee est tres etroite (de 0,1 a 1 mm) on obtient un effet de coupe avec une excellente hemostase au niveau des berges. Certes ces deux processus - coagulation et volatilisation - peuvent etre obtenus par d'autres procedes : echauffement par contact (sonde thermique) ou effet Joule (courant electrique haute frequence). Le laser a l'avantage de ne necessiter aucun contact mecanique entre le vecteur d'energie et les tissus ; on peut alors predire correctement la repartition d'energie au niveau des tissus et les effets sont tres repro-ductibles. Par ailleurs, l'absorption tissulaire variant considerablement avec la longueur d'onde on peut choisir la source laser en fonction des effets desires.

  16. Médecine des voyages

    PubMed Central

    Aw, Brian; Boraston, Suni; Botten, David; Cherniwchan, Darin; Fazal, Hyder; Kelton, Timothy; Libman, Michael; Saldanha, Colin; Scappatura, Philip; Stowe, Brian

    2014-01-01

    Résumé Objectif Définir la pratique de la médecine des voyages, présenter les éléments fondamentaux d’une consultation complète préalable aux voyages à des voyageurs internationaux et aider à identifier les patients qu’il vaudrait mieux envoyer en consultation auprès de professionnels de la médecine des voyages. Sources des données Les lignes directrices et les recommandations sur la médecine des voyages et les maladies liées aux voyages publiées par les autorités sanitaires nationales et internationales ont fait l’objet d’un examen. Une recension des ouvrages connexes dans MEDLINE et EMBASE a aussi été effectuée. Message principal La médecine des voyages est une spécialité très dynamique qui se concentre sur les soins préventifs avant un voyage. Une évaluation exhaustive du risque pour chaque voyageur est essentielle pour mesurer avec exactitude les risques particuliers au voyageur, à son itinéraire et à sa destination et pour offrir des conseils sur les interventions les plus appropriées en gestion du risque afin de promouvoir la santé et prévenir les problèmes médicaux indésirables durant le voyage. Des vaccins peuvent aussi être nécessaires et doivent être personnalisés en fonction des antécédents d’immunisation du voyageur, de son itinéraire et du temps qu’il reste avant son départ. Conclusion La santé et la sécurité d’un voyageur dépendent du degré d’expertise du médecin qui offre le counseling préalable à son voyage et les vaccins, au besoin. On recommande à ceux qui donnent des conseils aux voyageurs d’être conscients de l’ampleur de cette responsabilité et de demander si possible une consultation auprès de professionnels de la médecine des voyages pour tous les voyageurs à risque élevé.

  17. Science and Science Fiction

    ERIC Educational Resources Information Center

    Oravetz, David

    2005-01-01

    This article is for teachers looking for new ways to motivate students, increase science comprehension, and understanding without using the old standard expository science textbook. This author suggests reading a science fiction novel in the science classroom as a way to engage students in learning. Using science fiction literature and language…

  18. Vecteurs Singuliers des Theories des Champs Conformes Minimales

    NASA Astrophysics Data System (ADS)

    Benoit, Louis

    En 1984 Belavin, Polyakov et Zamolodchikov revolutionnent la theorie des champs en explicitant une nouvelle gamme de theories, les theories quantiques des champs bidimensionnelles invariantes sous les transformations conformes. L'algebre des transformations conformes de l'espace-temps presente une caracteristique remarquable: en deux dimensions elle possede un nombre infini de generateurs. Cette propriete impose de telles conditions aux fonctions de correlations qu'il est possible de les evaluer sans aucune approximation. Les champs des theories conformes appartiennent a des representations de plus haut poids de l'algebre de Virasoro, une extension centrale de l'algebre conforme du plan. Ces representations sont etiquetees par h, le poids conforme de leur vecteur de plus haut poids, et par la charge centrale c, le facteur de l'extension centrale, commune a toutes les representations d'une meme theorie. Les theories conformes minimales sont constituees d'un nombre fini de representations. Parmi celles-ci se trouvent des theories unitaires dont les representation forment la serie discrete de l'algebre de Virasoro; leur poids h a la forme h_{p,q}(m)=[ (p(m+1) -qm)^2-1] (4m(m+1)), ou p,q et m sont des entiers positifs et p+q<= m+1. L'entier m parametrise la charge centrale: c(m)=1 -{6over m(m+1)} avec n>= 2. Ces representations possedent un sous-espace invariant engendre par deux sous-representations avec h_1=h_{p,q} + pq et h_2=h_{p,q} + (m-p)(m+1-q) dont chacun des vecteurs de plus haut poids portent le nom de vecteur singulier et sont notes respectivement |Psi _{p,q}> et |Psi_{m-p,m+1-q}>. . Les theories super-conformes sont une version super-symetrique des theories conformes. Leurs champs appartiennent a des representation de plus haut poids de l'algebre de Neveu-Schwarz, une des deux extensions super -symetriques de l'algebre de Virasoro. Les theories super -conformes minimales possedent la meme structure que les theories conformes minimales. Les representations sont elements de la serie h_{p,q}= [ (p(m+2)-qm)^2-4] /(8m(m+2)) ou p,q et m sont des entiers positifs, p et q etant de meme parite, et p+q<= m+2. La charge centrale est donnee par c(m)={3over 2}-{12over m(m+2)} avec m >= 2. Les vecteurs singuliers | Psi_{p,q}> et |Psi_{m-p,m+2-q} > sont respectivement de poids h _{p,q}+pq/2 et h_ {p,q}+(m-p)(m+2-q)/2.. Les vecteurs singuliers ont une norme nulle et on doit les eliminer des representations pour que celles -ci soient unitaires. Cette elimination engendrent des equations (super-)differentielles qui dependent directement de la forme explicite des vecteurs singuliers et auxquelles doivent obeir les fonctions de correlations de la theorie. Ainsi la connaissance de ces vecteurs singuliers est intimement reliee au calcul des fonctions de correlation. Les equations definissant les vecteurs singuliers forment un systeme lineaire surdetermine dont le nombre d'equations est de l'ordre de N(pq), le nombre de partitions de l'entier pq. Puisque les vecteurs singuliers jouent un role capital en theorie conforme, il est naturel de chercher des formes explicites pour les vecteurs (ou pour des familles infinies de ceux -ci). Nous donnons ici la forme explicite pour la famille infinie de vecteurs singuliers ayant un de ses indices egal a 1, pour les algebres de Virasoro et de Neveu-Schwarz. Depuis ces decouvertes, d'autres techniques de construction des vecteurs singuliers ont ete developpees, dont celle de Bauer, Di Francesco, Itzykson et Zuber pour l'algebre de Virasoro qui reproduit directement l'expression explicite des vecteurs singuliers |Psi _{1,q}> et |Psi_{p,1}>. Ils ont utilise l'algebre des produits d'operateurs et la fusion entre representations irreductibles pour engendrer des relations de recurence produisant les vecteurs singuliers. Dans le dernier chapitre de cette these nous adaptons cet algorithme a la construction des vecteurs singuliers de l'algebre de Neveu-Schwarz.

  19. Zur Geschichte des Umweltbegriffs

    NASA Astrophysics Data System (ADS)

    Trepl, Ludwig

    1992-09-01

    Historically, the biological concept of living organisms from the early 19th century was a precondition for the evolution of the modern concept of the environment. The connection with the hermeneutic concept of the environment qua “landscape” was made through A. v. Humboldt's “physiognomy of plants” and the geographical sciences. At the turn of the 20th century, ecology was established as the “science of communities”. These are primarily considered to have formed through the adaptation of organisms to one another, and, therefore, to an inner environment of a superordinate system.

  20. Effet Hall et Magnetisme des Alliages Amorphes Nickel-Zirconium Fabriques Par Pulverisation

    NASA Astrophysics Data System (ADS)

    Morel, Robert

    Cette these se situe dans le cadre d'une etude des proprietes electroniques et structurales des alliages metalliques amorphes, en cours depuis quelques annees a l'Universite de Montreal. Ce programme nous a entre autres amene a caracteriser la magnetoresistivite et l'effet Hall d'alliages FeZr, CoZr et NiZr, ce qui a permis de mettre en evidence deux caracteristiques de l'effet Hall: Dans les alliages amorphes ferromagnetiques, la resistivite elevee engendre un effet Hall extraordinaire beaucoup plus important que celui enregistre dans les metaux cristallins. La polarisation des spins entrai ne une asymetrie de la diffusion qui, tant dans les phases cristalline et amorphe, est tenue responsable de cette contribution. L'autre particularite du comportement de Hall de ces systemes est le renversement de signe du coefficient de Hall ordinaire, qui passe du negatif au positif dans les echantillons plus riches en zirconium. Dans les metaux cristallins, un modele d'electrons libres predit un signe negatif a moins que la conduction ne soit dominee par les trous. Or, dans un milieu desordonne les memes concepts sont difficilement applicables et de nouvelles theories ont du etre elaborees pour expliquer ce phenomene. Jusqu'a maintenant, l'etude des alliages amorphes nickel-zirconium s'est faite surtout a partir d'echantillons fabriques par trempe sur roue. Malheureusement cette technique ne permet pas la fabrication d'alliages contenant plus de 70% de nickel, a l'exception du seul compose Ni _{90}Zr_{10 }. Pour pallier a cette lacune et etendre nos connaissance a l'ensemble de la gamme de compositions, nous avons fabrique par pulverisation cathodique des echantillons NiZr amorphes--et quelques alliages cristallins tres riches en nickel--couvrant une bonne partie de la gamme interdite par la technique de trempe sur roue. Dans un premier temps, par comparaison avec les resultats connus nous avons mis en evidence les similitudes et les differences entre les alliages obtenus par l'une et l'autre methode de fabrication. Il s'avere que le comportement intrinseque n'est pas different, mais que les echantillons pulverises sont plus sensibles a certaines anomalies de la structure que nous avons relevees et tente d'expliquer. L'etude des echantillons paramagnetiques permet de verifier que dans ces alliages le comportement de l'effet Hall apparent est la somme des contributions ordinaire, consequence de la force de Lorentz, et extraordinaire, etant donnee la tres forte valeur de coefficient de Hall extraordinaire notee dans ces systemes. Dans les alliages ferromagnetiques, l'etude systematique de l'aimantation en fonction de la temperature et de la composition est menee par le biais de la mesure de la resistivite de Hall. Elle permet de definir les principaux parametres magnetiques--temperature de Curie et aimantation--et de mettre en evidence le caractere itinerant du magnetisme et la contribution des fluctuations de spins. Ces mesures de resistivite de Hall dans les amorphes ferromagnetiques mettent aussi en lumiere un effet Hall extraordinaire qui se superpose a un effet Hall ordinaire semblable en grandeur a celui des cristallins. Il appert aussi que l'effet Hall extraordinaire est l'effet dominant, y compris qu dessus de la temperature de Curie. Cette etude du comportement de Hall et de quelques proprietes magnetiques des alliages amorphes NiZr contenant plus de 70% de nickel nous a donc permis de verifier que malgre la faible aimantation l'effet Hall extraordinaire est l'effet dominant, que l'effet Hall ordinaire est semblable a celui trouve dans les cristallins, et que l'ensemble de ces manifestations pouvait etre explique sans faire appel aux modeles quantiques.

  1. Peste des petits ruminants

    PubMed Central

    Parida, S.; Muniraju, M.; Mahapatra, M.; Muthuchelvan, D.; Buczkowski, H.; Banyard, A.C.

    2015-01-01

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  2. Peste des petits ruminants.

    PubMed

    Parida, S; Muniraju, M; Mahapatra, M; Muthuchelvan, D; Buczkowski, H; Banyard, A C

    2015-12-14

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  3. elecTUM: Umsetzung der eLearning-Strategie der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Rathmayer, Sabine; Gergintchev, Ivan

    An der TUM wurde ein umfassendes und integriertes eLearning-Konzept umgesetzt, welches Präsenzstudium und eLearning in allen Leistungsbereichen der Universität miteinander verzahnt. Ein besonderer Schwerpunkt lag dabei in der Schaffung einer effizienten und wettbewerbsfähigen integrierten eLearning Infrastruktur in Hinblick auf die noch weiter steigenden Studienanfängerzahlen ab dem Jahr 2011 sowie die Umsetzung von eBologna. Die Etablierung einer hochschulweiten Lernplattform stellte eine wesentliche Basis für die Umsetzung der eLearning-Strategie dar. Die wissenschaftliche und wirtschaftliche Anschlussfähigkeit im Hinblick auf eine Verwertung der Projektergebnisse wurde durch die aktive Beteiligung an einer Vielzahl hochschulübergreifender Arbeitskreise, Fachtagungen und Kooperationen, vor allem über Organisations- und Dienstleistungsmodelle sowie innovative technische Entwicklungen, sichergestellt.

  4. The Marine Language Exchange Program: an International Approach to Ocean Sciences

    NASA Astrophysics Data System (ADS)

    Nowell, A.; Robigou, V.

    2004-12-01

    The ability of scientists to communicate across cultural and linguistic barriers is crucial for the global economic sustainability and protection of the world's oceans. Yet students with majors in the sciences and engineering constitute less than 2% of those who study abroad each year. And even fewer are students who study in countries where English is not the first language. The Marine Language Exchange program is a case study of an international and interdisciplinary collaboration between faculties in the languages and the sciences that address this gap. A consortium of U.S. and European institutions including University of Washington (Washington), Eckerd College (Florida), University of Hilo (Hawaii), Université de la Rochelle (France), Université de Liège (Belgium), and Universidad de Las Palmas (Spain) is developing a multilingual, marine sciences exchange program in an effort to internationalize their ocean sciences departments. The program includes a three-week, intensive "bridge" course designed to reinforce second language skills in the context of marine sciences, and prepare undergraduate students for the cultural and educational differences of their host country. Following this preparatory immersion experience students from each institution enroll in courses abroad for 6 to 12 months to study marine sciences for full academic credit. Different disciplinary approaches -Second Language Acquisition, English as a Second Language and Marine Science- prepare science students to contribute to the study and the management of the world\\'{}s oceans with an awareness of the cultural issues reflected by national marine policies.

  5. Contribution a l'etude du comportement de dalles de ponts en beton arme de barres en PRF soumises a des charges concentrees simulant les charges de roues

    NASA Astrophysics Data System (ADS)

    Bouguerra, Kheireddine

    Au cours des dernieres annees, la deterioration des structures en beton arme a pris une ampleur sans precedent, et ce, malgre le fait que leur duree de vie en service initialement prevue est loin d'etre atteinte. La corrosion de l'armature d'acier est un des principaux facteurs reduisant la duree de vie des ponts en beton arme d'acier. Par ailleurs, l'armature en materiaux composites de polymeres renforces de fibres (PRF) constitue une solution a l'armature metallique afin de pallier au probleme de la corrosion d'acier et a la deterioration des structures en beton arme. Aussi, les barres d'armature en materiaux composites de PRF possedent une resistance en traction elevee (environ 2 a 6 fois la limite elastique de l'acier d'armature conventionnel), ce qui leur permet de constituer un renforcement structural attrayant pour les structures en beton. Le comportement d'elements structuraux en beton arme de barres en PRF est different de ceux en beton arme de barres d'acier. En effet, les barres en PRF possedent un module d'elasticite relativement plus faible que celui de l'acier et ont des proprietes d'adherence differentes de celles des barres d'acier. L'utilisation des barres d'armature en PRF pour armer les dalles de tabliers de ponts se concretise de plus en plus avec l'avancement des recherches dans ce domaine. La recherche entamee dans le cadre de cette these s'inscrit dans un programme de travaux realises au sein de la Chaire de recherche CRSNG/Industrie sur les Materiaux composites novateurs en PRF pour les infrastructures au departement de genie civil a l'Universite de Sherbrooke. Le comportement de membrures en beton arme de PRF soumis a des sollicitations mecaniques constitue un des principaux axes de recherche. Dans le cadre de cette these, une serie d'essais a ete effectuee sur huit dalles de ponts a confinement interne a grande echelle. Les parametres des essais comprennent: (1) l'epaisseur de la dalle, (2) le type et le taux d'armature transversale de l'assemblage inferieur, (3) la resistance en compression du beton, et (4) le taux d'armature dans les autres directions (armatures transversale et longitudinale de l'assemblage superieur et l'armature longitudinale de l'assemblage inferieur). Lors des essais de chargement, les dalles ont ete supportees par deux poutrelles metalliques espacees de 2000 mm centre a centre et soumises a une charge statique concentree sur une aire de contact de 600 mm x 250 mm afin de simuler une charge de camion (87,5 kN--CL-625) et ce conformement au code Canadien sur le calcul des ponts routiers [CAN/CSA-S6-06]. Aussi, une analyse numerique du comportement des dalles testees sous charges est faite a l'aide d'un logiciel d'elements finis ADINA version 8.2. Les essais ont montre que toutes les dalles testees ont rompu par poinconnement, peu importe le parametre etudie. Aussi, une epaisseur de dalle de 175 mm repond aux exigences du Canadien sur le calcul des ponts routiers [CAN/CSA-S6-06]. Par ailleurs, les resultats ont montre que la resistance en compression du beton est un parametre qui influe sur la deflexion, les deformations dans les barres et l'ouverture de fissures. Enfin, les resultats des analyses numeriques effectuees corroborent avec ceux obtenus experimentalement. Mots cles. Dalle de ponts en beton, armature de PRF, charges statiques, flexion, deformations, poinconnement, elements finis.

  6. Prise en charge des traumatismes graves du rein

    PubMed Central

    Lakmichi, Mohamed Amine; Jarir, Redouane; Sadiki, Bader; Zehraoui; Bentani; Wakrim, Bader; Dahami, Zakaria; Moudouni; Sarf, Ismail

    2015-01-01

    Les traumatismes graves du rein de grade III, IV et V selon la classification de l'Amercan Society for Surgery For Trauma (ASST) sont plus rares et se retrouvent dans 5% des cas en moyenne. Leur prise en charge est souvent délicate, nécessitant alors des centres expérimentés dotés de moyen adéquats d'imagerie (scanner spiralé). Cependant, durant ces dernières années, la prise en charge de ces traumatismes a évolué vers une attitude de moins en moins chirurgicale grâce à l’évolution des techniques de la radiologie interventionnelle, de l'endourologie et des moyens de surveillance aux urgences et de réanimation. L'objectif de cette étude est d’évaluer notre expérience dans la prise en charge des traumatismes rénaux de haut grade. Notre étude rétrospective porte sur 25 cas de traumatismes grave du rein de grade III, IV et V selon la classification de l'ASST, colligés entre Janvier 2002 et Juin 2009 au service d'urologie du centre Hospitalier Universitaire Mohammed VI, Université Cadi Ayyad de Marrakech, Maroc. Nous avons étudié les données épidémiologiques, les signes cliniques et biologiques à l'admission (état de choc hémorragique, taux d'hémoglobine), les données radiologiques (échographie et scanner), les lésions associées, la prise en charge thérapeutique et les complications. L’âge moyen de nos patients était de 24,9 ans 15 et 58 ans, avec une prédominance masculine (sex-ratio = 7, 3). Le rein droit était intéressé dans 15 cas (60%). Le traumatisme rénal était fermé dans 15 cas, et ouvert par arme blanche dans 10 cas. Huit patients se sont présentés en état de choc hémorragique (32%). Une anémie inférieur à 10g /100ml a été observée dans 10 cas (40%). L'uroscanner fait systématiquement à l'admission a retrouvé un grade III (10 cas), grade IV (13 cas) et grade V (2 cas). La prise en charge a consisté en une exploration chirurgicale avec néphrectomie chez 2 cas de Grade IV pour une instabilité hémodynamique. Une surveillance active clinique, biologique, et radiologique a été préconisée dans 23 cas (92%). Le scanner de contrôle fait à J7, a objectivé une stabilisation des lésions dans 17 cas et la constitution d'un urinome dans 2 cas drainé par sonde double J. Une néphrectomie d'hémostase était nécessaire dans 4 cas de grade IV (3 cas) et de grade V (1 cas). Un patient est décédé à J2 d'un traumatisme ouvert grade IV suite à une hémorragie foudroyante. La durée moyenne d'hospitalisation était de 17 jours (6-75 jours). A travers notre étude, on conforte l'attitude conservatrice recommandée actuellement dans la prise en charge de la plupart des traumatismes graves du rein en l'absence d'une instabilité hémodynamique, grâce aux mesures de réanimation correcte, une surveillance rapprochée du patient et le recours aux moyens endoscopiques de drainage des voies excrétrices. Grace à cette attitude la plupart de nos patients (76%) on conservé leur unités rénales, extrêmement précieuses en particulier pour les patients sujets à la dégradation ultérieure de leur fonction rénale, leur permettant ainsi d’éviter de tomber dans l'hémodialyse ou de rentrer dans des programmes de greffe rénale. PMID:26090064

  7. Science in Science Fiction.

    ERIC Educational Resources Information Center

    Allday, Jonathan

    2003-01-01

    Offers some suggestions as to how science fiction, especially television science fiction programs such as "Star Trek" and "Star Wars", can be drawn into physics lessons to illuminate some interesting issues. (Author/KHR)

  8. Classification of 3 DES Supernovae with OzDES

    NASA Astrophysics Data System (ADS)

    Moller, A.; Tucker, B. E.; Yuan, F.; Lewis, G.; Lidman, C.; Macaulay, E.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2016-02-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  9. Classification of 4 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Glazebrook, K.; Amon, A.; Lidman, C.; Martini, P.; Tucker, B. E.; Yuan, F.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  10. Classification of 6 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Lewis, G. F.; Mould, J.; Lidman, C.; Tucker, B. E.; Sharp, R.; Yuan, F.; Martini, P.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  11. Classification of 20 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Davis, T. M.; Kim, A. G.; Macualay, E.; Lidman, C.; Sharp, R.; Tucker, B. E.; Yuan, F.; Zhang, B.; Lewis, G. F.; Sommer, N. E.; Martini, P.; Mould, J.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  12. Classification of 15 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Yuan, F.; Tucker, B. E.; Lidman, C.; Martini, P.; Gshwend, Julia; Moller, A.; Zhang, B.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  13. Classification of 14 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Tucker, B. E.; Sharp, R.; Yuan, F.; Zhang, B.; Lidman, C.; Davis, T. M.; Hinton, S.; Mould, J.; Smith, R. C.; Schubnell, M.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Castander, F. J.; Desai, S.; Paech, K.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey. The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  14. High Resolution Stereo Camera (HRSC) on Mars Express - a decade of PR/EO activities at Freie Universität Berlin

    NASA Astrophysics Data System (ADS)

    Balthasar, Heike; Dumke, Alexander; van Gasselt, Stephan; Gross, Christoph; Michael, Gregory; Musiol, Stefanie; Neu, Dominik; Platz, Thomas; Rosenberg, Heike; Schreiner, Björn; Walter, Sebastian

    2014-05-01

    Since 2003 the High Resolution Stereo Camera (HRSC) experiment on the Mars Express mission is in orbit around Mars. First images were sent to Earth on January 14th, 2004. The goal-oriented HRSC data dissemination and the transparent representation of the associated work and results are the main aspects that contributed to the success in the public perception of the experiment. The Planetary Sciences and Remote Sensing Group at Freie Universität Berlin (FUB) offers both, an interactive web based data access, and browse/download options for HRSC press products [www.fu-berlin.de/planets]. Close collaborations with exhibitors as well as print and digital media representatives allows for regular and directed dissemination of, e.g., conventional imagery, orbital/synthetic surface epipolar images, video footage, and high-resolution displays. On a monthly basis we prepare press releases in close collaboration with the European Space Agency (ESA) and the German Aerospace Center (DLR) [http://www.geo.fu-berlin.de/en/geol/fachrichtungen/planet/press/index.html]. A release comprises panchromatic, colour, anaglyph, and perspective views of a scene taken from an HRSC image of the Martian surface. In addition, a context map and descriptive texts in English and German are provided. More sophisticated press releases include elaborate animations and simulated flights over the Martian surface, perspective views of stereo data combined with colour and high resolution, mosaics, and perspective views of data mosaics. Altogether 970 high quality PR products and 15 movies were created at FUB during the last decade and published via FUB/DLR/ESA platforms. We support educational outreach events, as well as permanent and special exhibitions. Examples for that are the yearly "Science Fair", where special programs for kids are offered, and the exhibition "Mars Mission and Vision" which is on tour until 2015 through 20 German towns, showing 3-D movies, surface models, and images of the HRSC camera experiment. Press and media appearances of group members, and talks to school classes and interested communities also contribute to the public outreach. For HRSC data dissemination we use digital platforms. Since 2007 HRSC image data can be viewed and accessed via the online interface HRSCview [http://hrscview.fu-berlin.de] which was built in cooperation with the DLR Institute for Planetary Research. Additionally HRSC ortho images (level 4) are presented in a modern MapServer setup in GIS-read format since 2013 [http://www.geo.fu-berlin.de/en/geol/fachrichtungen/planet/projects/marsexpress/level4downloads/index.html]. All of these offers ensured the accessibility of HRSC data and products to the science community as well as to the general public for the last ten years and will do so also in the future, taking advantage of modern and user-optimized applications and networks.

  15. Transport quantique dans des nanostructures

    NASA Astrophysics Data System (ADS)

    Naud, C.

    2002-09-01

    Quantum transport in nanostructures This work is devoted to the design, fabrication and magnetotransport investigations of mesoscopic devices. The sample are obtain by e-beam lithography and the measurements are performed at low temperature in a dilution refrigerator in the presence of a magnetic field. We have used MBE grown AlGaAs/GaAs heterojonctions as starting material to fabricate a bipartite tiling of rhombus called mathcal{T}3 lattice. We observe for the first time large amplitude h/e oscillations in this network as compared to the one measured in square lattices of similar size. These oscillations are the signature of a recently predited localization phenomenon induced by Aharonov-Bohm interferences on this peculiar topology. For particular values of the magnetic field the propagation of the electron wave function is bounded in a small number of cells, called Aharonov-Bohm cages. More strikingly, at high magnetic field, h/2e oscillations appear whose amplitude can be much higher than the fundamental period. Their temperature dependence is similar to that of the h/e signal. These observations withdraw a simple interpretation in terms of harmonics generation. The origin of this phenomenon is still unclear and needs more investigations. The influence electrical width of the wire defining the network and so the rule of the number of channels can be studied using a gate deposited over the lattice. In particular we have measured the amplitude dependence of the h/e and h/2e signal versus the gate voltage. Ce travail est consacr la ralisation d'chantillons msoscopiques partir de la lithographie lectronique ainsi qu' leur caractrisation trs basse temprature en magntotransport. Nous avons pour cela exploit le gaz bidimensionnel d'lectrons situ l'interface d'une htrojonction AlGaAs/GaAs pour raliser un rseau de boucle d'une gomtrie particulire baptise la gomtrie mathcal{T}3. Nous avons observ sur cette structure des oscillations de conductance en fonction du flux du champ magntique de priode h/e dont l'amplitude est beaucoup plus importante que celle mesure sur un rseau carr de mme dimension. Cette diffrence constitue une signature d'un effet de localisation induit par le champ magntique sur la topologie mathcal{T}3. Pour des valeurs spcifiques du champ magntique, du fait des interfrences destructives Aharonov-Bohm, la propagation des fonctions d'ondes est limite un ensemble fini de cellule du rseau appel cage. De la dpendance en temprature des oscillations de priode h/e mesures sur le rseau mathcal{T}3 nous avons tir une longueur caractristique qui peut tre rattache au primtre des cages. Un phnomne inattendu fut l'observation, pour des champs magntiques plus importants, d'un doublement de frquence des oscillations. Ces oscillations de priode h/2e pouvant avoir une amplitude suprieure aux oscillations de priode h/e, une interprtation en terme d'harmonique n'est pas possible. Enfin, l'influence de la largeur lectrique des fils constituant le rseau et donc celle du nombre de canaux par brin a t tudie en ralisant des grilles lectrostatique. Les variations de l'amplitude des signaux en h/e et h/2e en fonction de la tension de grille ont t mesurs.

  16. Latina Voices of Des Moines.

    ERIC Educational Resources Information Center

    Taylor, P. Dawn

    This dissertation examines the lives of Hispanic women living in Des Moines and includes their views of problems and opportunities involved in living in that city. Interviews were conducted with 24 Latino women over the age of 17 who had been in the area for over 2 years. Findings indicate that learning to speak English was the single most…

  17. The International Development Research Centre: A Guide for the Canadian University Research Community = Le Centre de recherches pour le developpement international: guide a l'intention des scientifiques des universites Canadiennes.

    ERIC Educational Resources Information Center

    Tillman, George; Wasilewski, Ania, Ed.

    Written in both English and French this is a manual for the Canadian research community. It describes the International Development Research Centre (IDRC) and its operations. The main objective of the IDRC is to assist scientists in developing countries to identify and conduct research into long term practical solutions to development problems.

  18. L'astronomie des Anciens

    NASA Astrophysics Data System (ADS)

    Nazé, Yaël

    2009-04-01

    Quelle que soit la civilisation à laquelle il appartient, l'être humain cherche dans le ciel des réponses aux questions qu'il se pose sur son origine, son avenir et sa finalité. Le premier mérite de ce livre est de nous rappeler que l'astronomie a commencé ainsi à travers les mythes célestes imaginés par les Anciens pour expliquer l'ordre du monde et la place qu'ils y occupaient. Mais les savoirs astronomiques passés étaient loin d'être négligeables et certainement pas limités aux seuls travaux des Grecs : c'est ce que l'auteur montre à travers une passionnante enquête, de Stonehenge à Gizeh en passant par Pékin et Mexico, fondée sur l'étude des monuments anciens et des sources écrites encore accessibles. Les tablettes mésopotamiennes, les annales chinoises, les chroniques médiévales, etc. sont en outre d'une singulière utilité pour les astronomes modernes : comment sinon remonter aux variations de la durée du jour au cours des siècles, ou percer la nature de l'explosion qui a frappé tant d'observateurs en 1054 ? Ce livre offre un voyage magnifiquement illustré à travers les âges, entre astronomie et archéologie.

  19. Proprietes optiques et mecanismes de relaxation de l'energie des porteurs dans des boites quantiques

    NASA Astrophysics Data System (ADS)

    Perret, Nathalie Emmanuelle

    L'objet de ce doctorat est l'etude des proprietes optiques, et en particulier de la relaxation de l'energie des porteurs dans des structures a boites quantiques d'InAs/GaAs. Le travail experimental a ete realise grace aux techniques de photoluminescence (PL) continue et de photoluminescence resolue dans le temps, sur des echantillons comprenant un tres grand nombre de boites. A l'aide des mesures experimentales effectuees sur une serie d'echantillons de boites quantiques interdiffusees a divers degres, et des calculs variationnels de leurs etats electroniques, nous avons demontre clairement que la largeur des raies d'emission de la PL, qui est due aux inhomogeneites dans l'ensemble de boites etudie, peut etre attribuee principalement a des fluctuations de la hauteur des boites. D'autre part, la determination des temps de montee et de decroissance des intensites de photoluminescence a montre l'importance de certains mecanismes de transport et de relaxation, en fonction des conditions experimentales. En effet, les temps caracteristiques de la capture, de la relaxation interniveaux et de la recombinaison des porteurs varient significativement, selon le mecanisme predominant, en fonction de la temperature, de la densite d'excitation et de la separation interniveaux quantiques. Ainsi, les principaux mecanismes mis en evidence sont: la localisation des porteurs dans les barrieres a basse temperature dans le cas des echantillons interdiffuses, les collisions de type Auger sous forte excitation, les processus multiphononiques et la re-emission thermique a haute temperature. Un modele de relaxation, base sur les equations d'evolution de la population de porteurs de chaque niveau quantique, a aussi ete developpe pour mieux identifier l'effet de chacun des principaux mecanismes de relaxation des porteurs considere separement. Ces simulations ont permis une analyse plus approfondie du role de ces mecanismes. Ainsi, nous avons mis en evidence l'importance de la localisation des porteurs dans la couche de mouillage, ainsi que l'importance des mecanismes de collisions Auger lors de la capture, la capture et la relaxation interniveaux des porteurs vers tous les niveaux d'energie inferieure simultanement. Finalement, les resultats experimentaux montrent que la relaxation de l'energie des porteurs est beaucoup plus rapide que cela avait ete predit initialement par la theorie du "phonon bottleneck". Nos resultats indiquent que l'intensite lumineuse emise par les boites est regie principalement par le taux de capture/relaxation interniveaux des porteurs dans les boites. Mais elle est limitee par la re-emission thermique des porteurs hors des boites, a haute temperature. (Abstract shortened by UMI.)

  20. DES exposure checker: Dark Energy Survey image quality control crowdsourcer

    NASA Astrophysics Data System (ADS)

    Melchior, Peter; Sheldon, Erin; Drlica-Wagner, Alex; Rykoff, Eli S.

    2015-11-01

    DES exposure checker renders science-grade images directly to a web browser and allows users to mark problematic features from a set of predefined classes, thus allowing image quality control for the Dark Energy Survey to be crowdsourced through its web application. Users can also generate custom labels to help identify previously unknown problem classes; generated reports are fed back to hardware and software experts to help mitigate and eliminate recognized issues. These problem reports allow rapid correction of artifacts that otherwise may be too subtle or infrequent to be recognized.

  1. Science and Science Fiction

    ScienceCinema

    Scherrer, Robert [Vanderbilt University, Nashville, Tennessee, United States

    2009-09-01

    I will explore the similarities and differences between the process of writing science fiction and the process of 'producing' science, specifically theoretical physics. What are the ground rules for introducing unproven new ideas in science fiction, and how do they differ from the corresponding rules in physics? How predictive is science fiction? (For that matter, how predictive is theoretical physics?) I will also contrast the way in which information is presented in science fiction, as opposed to its presentation in scientific papers, and I will examine the relative importance of ideas (as opposed to the importance of the way in which these ideas are presented). Finally, I will discuss whether a background as a research scientist provides any advantage in writing science fiction.

  2. Science and Science Fiction

    SciTech Connect

    Scherrer, Robert

    2006-03-29

    I will explore the similarities and differences between the process of writing science fiction and the process of 'producing' science, specifically theoretical physics. What are the ground rules for introducing unproven new ideas in science fiction, and how do they differ from the corresponding rules in physics? How predictive is science fiction? (For that matter, how predictive is theoretical physics?) I will also contrast the way in which information is presented in science fiction, as opposed to its presentation in scientific papers, and I will examine the relative importance of ideas (as opposed to the importance of the way in which these ideas are presented). Finally, I will discuss whether a background as a research scientist provides any advantage in writing science fiction.

  3. (Networking + Integrating) * (Systems + Society). Proceedings of the Annual Canadian Conference of Information Science (12th, Toronto, Ontario, May 14-16, 1984) = (Reseaux + Integration) * (Systemes + Societe). Comptes rendus de la conference annuelle Canadienne des sciences de l'information (12th, Toronto, Ontario, 14-16 mai, 1984).

    ERIC Educational Resources Information Center

    Canadian Association for Information Science, Ottawa (Ontario).

    Seventeen papers from the 1984 annual conference of the Canadian Association for Information Science (CAIS) are presented in four broad topic areas. The first group, which focuses on changing roles in information access, includes the keynote address by Charles Meadow, "Integrating Access to Information Utilities: Promises, Problems, and Profiles…

  4. EDITORIAL: Computational materials science Computational materials science

    NASA Astrophysics Data System (ADS)

    Kahl, Gerhard; Kresse, Georg

    2011-10-01

    Special issue in honour of Jürgen Hafner On 30 September 2010, Jürgen Hafner, one of the most prominent and influential members within the solid state community, retired. His remarkably broad scientific oeuvre has made him one of the founding fathers of modern computational materials science: more than 600 scientific publications, numerous contributions to books, and a highly cited monograph, which has become a standard reference in the theory of metals, witness not only the remarkable productivity of Jürgen Hafner but also his impact in theoretical solid state physics. In an effort to duly acknowledge Jürgen Hafner's lasting impact in this field, a Festsymposium was held on 27-29 September 2010 at the Universität Wien. The organizers of this symposium (and authors of this editorial) are proud to say that a large number of highly renowned scientists in theoretical condensed matter theory—co-workers, friends and students—accepted the invitation to this celebration of Hafner's jubilee. Some of these speakers also followed our invitation to submit their contribution to this Festschrift, published in Journal of Physics: Condensed Matter, a journal which Jürgen Hafner served in 2000-2003 and 2003-2006 as a member of the Advisory Editorial Board and member of the Executive Board, respectively. In the subsequent article, Volker Heine, friend and co-worker of Jürgen Hafner over many decades, gives an account of Hafner's impact in the field of theoretical condensed matter physics. Computational materials science contents Theoretical study of structural, mechanical and spectroscopic properties of boehmite (γ-AlOOH) D Tunega, H Pašalić, M H Gerzabek and H Lischka Ethylene epoxidation catalyzed by chlorine-promoted silver oxide M O Ozbek, I Onal and R A Van Santen First-principles study of Cu2ZnSnS4 and the related band offsets for photovoltaic applicationsA Nagoya, R Asahi and G Kresse Renormalization group study of random quantum magnetsIstván A Kovács and Ferenc Iglói Ordering effects in disordered systems: the Au-Si systemN Jakse, T L T Nguyen and A Pasturel On the stability of Archimedean tilings formed by patchy particlesMoritz Antlanger, Günther Doppelbauer and Gerhard Kahl

  5. Preface: Materiaux 2010

    NASA Astrophysics Data System (ADS)

    Cheikhrouhou, Abdelwaheb

    2012-02-01

    The national conference 'MATERIAUX 2010', which took place in Mahdia (Tunisia), from 4-7 November 2010 was organized by The 'Tunisian Materials Research Society: Tu-MRS' in collaboration with the Materials Physics Laboratory of Sfax 'LPM', Faculty of Sciences, Sfax University and the Research Unit ' Physique, Informatique et Mathématiques ', Faculty of Sciences, Gafsa University The First National Conference on Materials 'MATERIAUX 2006' was organized in Douz (Tunisia) in December 2006. This was followed by 'MATERIAUX 2007' held in Hammamet (Tunisia) in April 2007 and the National Conference 'MATERIAUX 2009' organized jointly with the Second 'Journées Internationales de la Physique des Matériaux et Applications: JIPMA 2009' in Gafsa (Tunisia) from 20-24 December 2009. 'MATERIAUX 2010' is intended to provide an excellent opportunity for National, Maghreb and International researchers to make their own work on materials known to a wider audience and to have discussions with other participants. This conference will also be an opportunity to exchange experiences, create and consolidate cooperation between different research structures in the Maghreb countries and also the countries around the Mediterranean. This conference will equally promote research development, contribution to collaboration between universities and the socio-economical milieu. More than 300 senior researchers, Professors, PhD and Masters students attended this conference from Tunisia, Algeria, Morocco, France, Spain and Canada. Several researchers, engineers and managers from industrial firms also attended. The conference consisted of plenary talks (8), oral contributions (40) and poster presentations (250). The topics of the Conference were: Nano-materials, nano-systems, thin films, surfaces and interfaces, applications Multifunctionnal materials, magnetic materials, dielectric materials, superconducting materials, applications,... Materials for electronics, informatics and communication Ceramics, glasses, polymers Natural materials (phosphates, clay,...) Metallic materials, alloys, metallurgy,... Others (materials and environment, materials and energy, biomaterials,...) I want to thank the scientific committee, the organizing committee, the local committee and everyone who contributed to the organization of this meeting for their invaluable efforts in order to guarantee the complete success of this conference. Abdelwaheb Cheikhrouhou President of 'Tu-MRS' Chairman of the Conference 'MATERIAUX 2010' Conference photograph Committies Organizing Committee Chairman CHEIKHROUHOU Abdelwaheb (Faculté des Sciences de Sfax) Members ALAYA Sahbi (Faculté des Sciences de Gabès) BENNACEUR Raouf (Faculté des Sciences de Tunis) BEN SALEM Mohamed (Faculté des Sciences de Bizerte) CHEIKHROUHOU-KOUBAA Wissem (Faculté des Sciences de Sfax) EL JANI Belgacem (Faculté des Sciences de Monastir) EZZAOUIA Hatem (Centre de Recherches et de Technologies de l'Energie, Technopole de Borj Cédria) LAMLOUMI Jilani (Ecole Supérieure des Sciences et Techniques de Tunis) REZIG Bahri (Ecole Nationale d'Ingénieurs de Tunis) Local Committee Chairman CHEIKHROUHOU Abdelwaheb (Faculté des Sciences de Sfax) Members CHEIKHROUHOU-KOUBAA Wissem (Faculté des Sciences de Sfax) KOUBAA Mohamed (Institut Supérieur de Biotechnologie de Sfax) NJEH Anwar (Institut Préparatoire aux Etudes d'Ingénieurs de Sfax) BEN SALAH Issam (Faculté des Sciences de Sfax) TAKKALI Férid (Faculté des Sciences de Sfax) REGAIEG Yassin (Faculté des Sciences de Sfax) OTHMANI Safa (Faculté des Sciences de Sfax) MNASSRI Rafik (Faculté des Sciences de Sfax) Secretariat BEN GHOZLEN Afifa (Faculté des Sciences de Sfax) BOUGHARIOU Sana (Faculté des Sciences de Sfax) Scientific Committee M. ADDOU, Faculté des Sciences de Kénitra (Morocco) N. AMDOUNI, Faculté des Sciences de Tunis (Tunisia) M. BACCOUCHE, Faculté des Sciences d'Annaba (Algeria) H. BATIS, Faculté des Sciences de Tunis (Tunisia) A. BELAFHAL, Faculté des Sciences d'El Jadida (Morocco) M.H. BEN GHOZLEN, Faculté des Sciences de Sfax (Tunisia) R. BENNACEUR, Faculté des Sciences de Tunis (Tunisia) B. BENYOUCEF, Université Abou Bakr Belkaid, Tlemcen (Algeria) M. BEN SALEM, Faculté des Sciences de Bizerte (Tunisia) B. BESSAIES, Centre de Recherches et Technologies de l'Energie (Tunisia) H. BOUCHRIHA, Faculté des Sciences de Tunis (Tunisia) W. BOUJELBEN, Faculté des Sciences de Sfax (Tunisia) A. CHEIKHROUHOU, Faculté des Sciences de Sfax (Tunisia) W. CHEIKHROUHOU-KOUBAA, Faculté des Sciences de Sfax (Tunisia) R. CHTOUROU, Centre de Recherches et Technologies de l'Energie (Tunisia) M. DEBBABI, Ecole Nationale d'Ingénieurs de Monastir (Tunisia) A. DAKHLAOUI, Faculté des Sciences de Bizerte (Tunisia) A. DINIA, Université de Strasbourg (France) B. ELJANI, Faculté des Sciences de Monastir (Tunisia) A. ELJAZOULI, Faculté des Sciences Ben Msik, Casablanca (Morocco) Z. FAKHFAKH, Faculté des Sciences de Sfax (Tunisia) A. GASMI, Faculté des Sciences d'Annaba (Algeria) A. GHARBI, Faculté des Sciences de Tunis (Tunisia) R. GHARBI, Faculté des Sciences de Sfax (Tunisia) K. GUIDARA, Faculté des Sciences de Sfax (Tunisia) H. GUERMAZI, Institut Préparatoire aux Etudes d'Ingénieurs de Sfax (Tunisia) S. GUERMAZI, Faculté des Sciences de Sfax (Tunisia) M. HADDAD, Faculté des Sciences de Meknès (Morocco) A. HAJ AMARA, Faculté des Sciences de Bizerte (Tunisia) D. HAMANA, Faculté des Sciences de Constantine (Algeria) N. KAMOUN, Faculté des Sciences de Tunis (Tunisia) S. KADDOUR-CHARFI, Faculté des Sciences de Tunis (Tunisia) M. KADDOUR, Faculté des Sciences de Sfax (Tunisia) M. KHITOUNI, Faculté des Sciences de Sfax (Tunisia) T. MHIRI, Faculté des Sciences de Sfax (Tunisia) Y. MLIK, Institut Préparatoire aux Etudes Scientifiques et Techniques (Tunisia) N. MLIKI, Faculté des Sciences de Tunis (Tunisia) A. NJAH, Faculté des Sciences de Gafsa (Tunisia) M. OUESLATI, Faculté des Sciences de Tunis (Tunisia) K. ZELLAMA, Faculté des Sciences d'Amiens (France) Invited Speakers AMMAR-MERIAH Souad, ITODYS, Université Paris Diderot (France) BEN SALEM Mohamed, Faculté des Sciences de Bizerte, Université du 7 Novembre á Carthage (Tunisia) CHEIKHROUHOU Abdelwaheb, Faculté des Sciences de Sfax, Université de Sfax (Tunisia) DAKHLAOUI Amel, Faculté des Sciences de Bizerte, Université du 7 Novembre á Carthage (Tunisia) DJABBAR Ahmed, Université des Sciences et des Technologies de Lille (France) DURASTANTI Félix, Centre d'Etudes et Recherche en Thermique, Environnement et Systèmes (C.E.R.T.E.S.), Université Paris Est- Créteil (France) FERY-FORGUES Suzanne, Université Paul Sabatier, Toulouse (France) GIRAUD Romain, Laboratoire de Photonique et de Nanostructures, CNRS/LPN, Marcoussis (France)

  6. Classification of DES15S2myz and DES15S2mwz by GTC

    NASA Astrophysics Data System (ADS)

    Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.

    2015-12-01

    We report optical spectroscopy of DES15S2myz and DES15S2mwz discovered by the Dark Energy Survey (ATel #4668). The spectra (495-920nm) were obtained using OSIRIS on the Gran Telescopio CANARIAS (GTC).

  7. Science in science fiction

    NASA Astrophysics Data System (ADS)

    Allday, Jonathan

    2003-01-01

    Science fiction, from Star Trek to Star Wars, is hugely popular and pupils will surely have encountered good and bad physics there, but do they really notice? Discussing the science implied in books and movies, such as in the use of transporters, can be a good way of getting students interested in physics.

  8. Soins primaires des personnes victimes d’une lésion médullaire

    PubMed Central

    McColl, Mary Ann; Aiken, Alice; McColl, Alexander; Sakakibara, Brodie; Smith, Karen

    2012-01-01

    Résumé Objectif Effectuer une étude de la portée des données empiriques, entre 1980 et 2009, concernant les soins primaires aux adultes victimes d’une lésion médullaire (LME). Sources des données Une recension dans des revues révisées par des pairs de1980 à 2009 à l’aide de CINAHL, PubMed-MEDLINE, EMBASE, PsycINFO, Social Sciences Abstracts et Social Work Abstracts. Sélection des études La recherche électronique au moyen de mots-clés a permis de cerner 42 articles sur les soins primaires et les LME. Des critères d’inclusion ont servi à réduire la liste à un ensemble de 21 articles publiés en anglais qui portaient sur un échantillon de plus de 3 et présentaient une analyse empirique. Synthèse Environ 90 % des personnes atteintes d’une LME ont identifié leur médecin de famille comme étant leur docteur habituel; 63 % avaient un spécialiste des LME. Les personnes vivant à long terme avec une LME développent des rubriques complexes pour naviguer dans leurs systèmes de soins de santé personnels. Les données scientifiques ne sont pas unanimes quant à l’efficacité des programmes d’intervention directe pour le maintien de la santé et la prévention des complications à la suite d’une LME. Les données appuient cependant le suivi périodique par une équipe spécialisée et un bilan de santé annuel complet. La recherche fait valoir un fort degré d’uniformité dans l’identification des problèmes les plus courants soulevés par les personnes atteintes d’une LME en soins primaires, dont la plupart concernent l’incapacité, plus précisément les complications secondaires, comme la dysfonction intestinale ou vésicale et la douleur. Il existe aussi de bonnes données probantes à l’effet que de nombreux problèmes de santé généraux exigent de l’attention dans une telle population, comme les problèmes de la densité osseuse, la dépression et les questions entourant la santé sexuelle et la reproduction. Il y a des données de niveaux 4 et 5 concernant des besoins en matière de santé non satisfaits qu’ont des personnes victimes d’une LME vivant dans la communauté. En dépit du fait que les patients atteints d’une LME utilisent beaucoup les soins primaires et les services de santé en général, les données scientifiques font valoir que les besoins de renseignements de ces patients en particulier ne sont pas adéquatement satisfaits. Conclusion Un solide système de soins primaires représente la meilleure assurance de bons résultats sur le plan de la santé et d’une utilisation raisonnable des services de santé chez les personnes victimes d’une LME, notamment un bilan de santé annuel complet, un recours approprié aux autres spécialistes et une attention accordée à l’accessibilité et aux besoins insatisfaits.

  9. Annuaire du Bureau des longitudes - 2006

    NASA Astrophysics Data System (ADS)

    Imcce; Bureau Des Longitudes

    2005-07-01

    This annual publication provides ephemerides and data to the use of professionnal and amateur astronomers. Divided in 11 chapters it covers concordance of various calendars, explanation of fondamental astronomy and various time scales, explanation for the use of ephemerides; tables provide ephemerides (positions, rise/set/passage) of the Sun and the Moon, planets, planetary satellites, asteroids, comets, bright stars; data and explanation for the physical observation of the surface of the Sun, the Moon, and planets; chart of the sky and a list of constellations and galaxies; prediction and ephemerides for astronomical phenomenon: occultation by the moon, stellar occultations by asteroids and appulses, solar eclipses and lunar eclipses; and an additional review about a hot scientific topic, this year: "Legendre et le méridien terrestre, 200 ans après". Cette publication annuelle fournit des éphémérides et des données à l'usage des astronomes professionnels et des astronomes amateurs. Composée de 11 chapitres elle comprend les rubriques sur les différents calendriers et leurs concordance, les fêtes légales en France, les dates et décrets sur les heures légales en France métropolitaine ; une introduction à l'astronomie fondamentale et aux différentes échelles de temps, des explications sur l'utilisation des éphémérides ; des tables fournissent les éphémérides (positions, heures de lever/coucher/passage) du Soleil et de la Lune, de planètes, de satellites naturels, d'astéroïdes, de comètes, d'étoiles brillantes ; des données pour l'observation de la surface du Soleil, de la Lune, et des planètes ; des cartes du ciel ainsi qu'une liste de constellations et de galaxies ; des prédictions des phénomènes astronomiques : occultation par la Lune, occultation stellaires par des astéroïdes et appulses, éclipses de Soleil et de la Lune; la liste et les coordonnées des observatoires astronomiques les plus connus ; et enfin un cahier thématique sur un sujet d'actulaité, pour cette année : "Legendre et le méridien terrestre, 200 ans après".

  10. "La Main a la Pate": A Programme to Renew Science Education in Primary Schools

    ERIC Educational Resources Information Center

    Belay, Raynald; Jasmin, David; Lena, Pierre

    2007-01-01

    In this article the authors introduce "La main a la pate," an international programme based in France that focuses on enquiry-based science. Since 1996, the Academie des sciences in France has been engaged in serious intervention in order to renew science education in primary schools. Based on enquiry-teaching principles, and closely coordinated…

  11. Terre des Lasers: the new Aquitaine outreach and communication center in photonics

    NASA Astrophysics Data System (ADS)

    Prulhiere, Jean Paul; Sarger, Laurent

    2009-06-01

    The competitive cluster "Route des Lasers" has been labeled by the French Government in July 2005. In this context, it has launched in September 2005, in cooperation with Commissariat à l'Energie Atomique (CEA) and Regional Council a project involving scientific exhibitions, called "Terre des Lasers ®", in order to create an exhibition and an area of communication and science discovery or a very large target (public, school, industry) in the fields of optics, lasers, optronics and imaging. This initiative is part of the strategy of the "Route des Lasers" center which aims to promote technologies developed in the areas of photonics, targeting in particular children and teenagers and their awareness for this particular industrial and scientific topic.

  12. BOOK REVIEW: Die Universitäts-Sternwarte München im Wandel ihrer Geschichte

    NASA Astrophysics Data System (ADS)

    Duerbeck, H. W.; Haefner, R.

    2003-01-01

    This concise history of Munich Observatory, written by a staff member, is actually the second, enlarged and updated edition of a brochure that was based on a pair of articles in the now defunct journal Die Sterne (Vol. 68, 263 and 340, 1992). First attempts to establish an observatory in Munich date back to 1759, when the Bavarian Academy of Sciences was founded and a topographic survey was begun; but these private attempts did not lead to a permanent installation. A more official interest arose when a topographic bureau was opened under French direction in 1801, and when the prince-elect Max IV Joseph planned a new land tax which required precise mapping. The collapse of the French rule also meant a collapse of the plans for the new observatory. In 1816, however, things began to develop with an unprecedented speed. The astronomer and surveyor Johann Georg von Soldner was appointed to become observatory director, and king Max I Joseph gave the order to erect the new observatory, which was completed near the end of 1817. The location was chosen near the the village of Bogenhausen (now a suburb of Munich). It took a little longer to install the instrumentation; first observations started in early 1819. Soldner's circle of friends comprised local instrument makers, including Fraunhofer and Reichenbach. With the former, he completed a new apparatus for experiments on the nature of the light of the fixed stars, a refractor of 10 cm aperture equipped with an objective prism. The study of sunlight, began by Fraunhofer, was now extended to the light of planets and fixed stars. Soldner also started a continuous meteorological record. But his name will always be remembered in the annals of science because of a short note, published in 1801 when he was still a student of Bode in Berlin, his On the deviation of a light ray from its rectilinear motion by the attraction of a celestial body which it passes at short distance. Soldner's last years were darkened by illness and enmities. Unfortunately the book does not tell anything about the notorious lunar observer Franz von Paula Gruithuisen, who was appointed professor of astronomy at Munich University in 1826. Soldner died in 1833, and his position was taken by Johann von Lamont, who did pioneering astrometric measurements of Halley's comet, took up again Fraunhofer's and Soldners studies of stellar spectra, but then felt that he should concentrate on only a few studies (stellar positions, magnetic and meteorological measurements). In addition he installed a mechanical workshop in the observatory, where many of the instruments were built, and which exists till the present day. After his death, a three-year vacancy of the director's chair was filled by the mathematician Ludwig Seidel. This was followed by the long reign of Hugo von Seeliger, beginning in 1882 and only ending in 1924. He is most famous for his studies in stellar statistics and other theoretical fields, but he was also active in observational work, including the timeservice. The following 25 years saw two less known directors, Alexander Wilkens and Wilhelm Rabe. After the latter's dismissal, Erich Schoenberg, a theoretician from Breslau, took over in 1949. Numerous changes had happened since Seeliger's time: the integration of a private solar observatory in Herrsching in 1932, which was dissolved in 1946, the transformation into a ``University Observatory'' in 1937/8, major damages through air raids in 1944, and finally, in 1949, the integration of the Wendelstein Solar Observatory, founded by the Deutsche Versuchsanstalt für Luftfahrt in 1941, as one of a series of stations to monitor solar activity. Schoenberg's retirement in 1955 was followed by an interim time of six years. In the following 21 years, Peter Wellmann re-shaped the observatory by building a research group on stellar atmospheres, one of the fields in which the observatory still excels. In the era of Rolf Kudritzki (1982 - 1998), these studies were further pursued and extended. An overview of the Observatory's actual research fields, research installations, its development of modern instrumentation, as well as its activities in public outreach (dating back to TV programmes by R. Kühn in the 1950s which the reviewer still vividly recalls) conclude this historic overview. The appendix lists the Observatory's publication series, statistics of recent publications and their impact, as well as post statistics of the institute - the booklet may also have been written to serve as a lobbying tool for governmental and private sponsorship. Häfner has succeeded in writing a concise sketch of the history of a an important German astronomical institution. It contains a lot of citations from original sources, printed in italics (without indicating their exact locations - this is understandable since Häfner did not want to write an ``academic'' article full of references and footnotes), as well as a useful bibliography.

  13. Des Lacs River and Souris River

     The Des Lacs River coming in to the Souris River. Des Lacs River is the darker water, which is sediment and the Souris River is the lighter water. >Photo taken by USGS personnel on a Civil Air Patrol flight....

  14. Regard pluriel sur l'enseignement et l'apprentissage des mathematiques a l'ecole primaire.

    ERIC Educational Resources Information Center

    Lopez, Lucie Mottier

    The texts gathered in this document come from work done in the framework of two postgraduate courses at the Faculte des Sciences de l'Education, Geneva: (1) "Learning: Meta-cognitive et socio-cognitive dimensions" course; and (2) "Didactical analysis of the interactions in class: Case study of mathematics at school" course. The problematics dealt…

  15. Soapy Science. Teaching Science.

    ERIC Educational Resources Information Center

    Leyden, Michael

    1997-01-01

    Describes a science and math activity that involves bubbles, shapes, colors, and solid geometry. Students build geometric shapes with soda straws and submerge the shapes in soapy water, allowing them to review basic geometry concepts, test hypotheses, and learn about other concepts such as diffraction, interference colors, and evaporation. (TJQ)

  16. Communicating Science

    NASA Astrophysics Data System (ADS)

    Russell, Nicholas

    2009-10-01

    Introduction: what this book is about and why you might want to read it; Prologue: three orphans share a common paternity: professional science communication, popular journalism, and literary fiction are not as separate as they seem; Part I. Professional Science Communication: 1. Spreading the word: the endless struggle to publish professional science; 2. Walk like an Egyptian: the alien feeling of professional science writing; 3. The future's bright? Professional science communication in the age of the internet; 4. Counting the horse's teeth: professional standards in science's barter economy; 5. Separating the wheat from the chaff: peer review on trial; Part II. Science for the Public: What Science Do People Need and How Might They Get It?: 6. The Public Understanding of Science (PUS) movement and its problems; 7. Public engagement with science and technology (PEST): fine principle, difficult practice; 8. Citizen scientists? Democratic input into science policy; 9. Teaching and learning science in schools: implications for popular science communication; Part III. Popular Science Communication: The Press and Broadcasting: 10. What every scientist should know about mass media; 11. What every scientist should know about journalists; 12. The influence of new media; 13. How the media represents science; 14. How should science journalists behave?; Part IV. The Origins of Science in Cultural Context: Five Historic Dramas: 15. A terrible storm in Wittenberg: natural knowledge through sorcery and evil; 16. A terrible storm in the Mediterranean: controlling nature with white magic and religion; 17. Thieving magpies: the subtle art of false projecting; 18. Foolish virtuosi: natural philosophy emerges as a distinct discipline but many cannot take it seriously; 19. Is scientific knowledge 'true' or should it just be 'truthfully' deployed?; Part V. Science in Literature: 20. Science and the Gothic: the three big nineteenth-century monster stories; 21. Science fiction: serious literature of ideas or low-grade entertainment?; 22. Science in British literary fiction; 23. Science on stage: the politics and ethics of science in cultural and educational contexts.

  17. Etude des effets du martelage repetitif sur les contraintes residuelles

    NASA Astrophysics Data System (ADS)

    Hacini, Lyes

    L'assemblage par soudage peut engendrer des contraintes residuelles. Ces contraintes provoquent des fissurations prematurees et un raccourcissement de la duree de vie des composants. Dans ce contexte, le martelage robotise est utilise pour relaxer ces contraintes residuelles. Trois volets sont presentes: le premier est l'evaluation des effets des impacts unitaires repetes sur le champ de contraintes developpe dans des plaques d'acier inoxydable austenitique 304L vierges ou contenant des contraintes residuelles initiales. Dans la deuxieme partie de ce projet, le martelage est applique grace au robot SCOMPI. Les contraintes residuelles induites et relaxees par martelage sont ensuite mesurees par la methode des contours, qui a ete adaptee a cet effet. Dans la troisieme partie, le martelage est modelise par la methode des elements finis. Un modele axisymetrique developpe grace au logiciel ANSYS permet de simuler des impacts repetes d'un marteau elastique sur une plaque ayant un comportement elastoplastique.

  18. Effets perturbateurs endocriniens des pesticides organochlores.

    PubMed

    Charlier, C; Plomteux, G

    2002-01-01

    Xenoestrogens such organochlorine pesticides are known to induce changes in reproductive development, function or behaviour in wildlife. Because these compounds are able to modify the estrogens metabolism, or to compete with estradiol for binding to the estrogen receptor, it may be possible that these products affect the risk of developing impaired fertility, precocious puberty or some kinds of cancer in man. Le plus ancien rcit de lutte contre la pollution remonte une lgende indienne racontant que la divinit Sing-bonga tait incommode par les manations des fours dans lesquels les Asuras fondaient leurs mtaux (1). Evidemment depuis, la problmatique n-a cess de s-accrotre et la contamination de la Terre par de nombreux polluants est devenue aujourd-hui un problme majeur de notre Socit. La protection de notre environnement est une question capitale qui doit tre respecte malgr la pression conomique actuelle et qui ne cessera de crotre au cours des prochaines annes mme si l-identification objective et indiscutable de ce qui est essentiel - donc devant tre prioritairement garanti sur la plante - est difficile cerner (2). Un oiseau en mauvais tat ne pond pas de bons oeufs disait un proverbe grec. Mais ce n-est qu- partir de la seconde moiti du XXme sicle que les toxicologues ont commenc identifier les effets qu-avaient entrans l-chelle mondiale les pollutions mises aux XIXme sicle sur la faune sauvage et sur le cheptel (3). L-histoire contemporaine des pesticides industriels commence vers 1874 (synthse des organochlors) et se poursuit tout au long de ces 2 sicles en passant par la synthse des organophosphors (1950), des carbamates (1970) et des pyrthrodes (1975) (4). Le dichlorodiphnyltrichlorothane (DDT) a t synthtis pour la premire fois par un tudiant en cours de prparation de sa thse de doctorat : Othmer Zeidler. La production, reprise par les entreprises F.Mayo puis par la Geigy Co. a d-abord intress l-arme, puis l-agriculture. Ds la fin de la 2(me) guerre mondiale, des mises en garde furent lances propos des effets nocifs du produit (4). Un dclin des populations de grives, d-aigles chauves, d-orfaies et de mammifres consommateurs de poissons fut constat partir des annes 50 et dnonc par Rachel Carson dans son clbre appel du Silent Spring de 1962. Bien qu-il soit interdit en Occident depuis les annes 70, ce produit a t tellement utilis et prsente une rmanence si longue qu-une contamination ubiquitaire existe aujourd-hui encore. De plus, ce produit continue tre produit aux USA pour tre utilis des fins de dmoustification dans les pays en voie de dveloppement. Il en va de mme de l-Hexachlorobenzne (HCB), un autre organochlor dont l-usage est interdit sous nos latitudes, mais reste frquent dans d-autres pays. Ces deux exemples indiquent que le problme de la contamination continue nous concerner, mme pour des produits dont l-usage est aujourd-hui strictement rglement ou interdit. Des effets sur la faune semblent encore actuellement devoir tre attribus ces produits. La diminution de la population des phoques dans la mer de Wadden pourrait tre due la forte contamination en composants organochlors des poissons dont ces phoques se nourrissent (5). Expos au DDT et son mtabolite dichlorodiphenyldichlorothylne (DDE), le Seratherodon mossambicus prsente une rduction de la scrtion de cortisol par une action toxique cytospcifique sur l-axe hypothalamo-hypophysaire (6). Des travaux rcents ont montr que le DDT et le DDE se lient chez les oiseaux et les mammifres au moyen de liaisons covalentes aux cellules de la zona fasciculata - homologue du tissu interrnal du poisson - induisant des microhmorragies. Cette dfaillance cortisolique peut s-accompagner d-une perturbation du mtabolisme glucidique et notamment d-un taux lev de glycogne hpatique (7). Les pesticides organochlors (DDT, DDE) entranent galement des perturbations d-ordre mtabolique chez certaines espces d-oiseaux, notamment le faucon plerin en Grande Bretagne et les oiseaux piscivores des grands lacs nord amricains o l-on a constat au cours des annes 1960 que leur reproduction tait menace et qu-une des manifestations les plus videntes des perturbations observes tait le taux lev de malformations (8). Des mortalits leves de poissons ou de coquillages ont t rapportes dans des levages situs proximit des zones d-pandage de pesticides organophosphors et de carbamates. En 1991, la dispersion arienne de fenitrothion dans le but de provoquer la dmoustication en Languedoc a t l-origine de la perte de plusieurs tonnes de crevettes japonaises. L-utilisation de trichlorfon et de dichlorvos comme antiparasitaires dans des fermes d-levages de saumons a provoqu des pisodes de mortalit importante (9). PMID:24862516

  19. The Construction of a New Science by Means of an Institute and Its Communication Media: The Institute of Educational Sciences in Geneva (1912-1948)

    ERIC Educational Resources Information Center

    Hofstetter, Rita

    2004-01-01

    This article is aimed at understanding some mechanisms implied in the construction of educational sciences as a disciplinary field in interaction with other social fields. Its object is the Genevan "Institut des sciences de l'education" from 1912 to 1948. This institution is analyzed from two main points of view: the foundation and development of…

  20. Food Science.

    ERIC Educational Resources Information Center

    Barkman, Susan J.

    1996-01-01

    Presents food science experiments designed for high school science classes that aim at getting students excited about science and providing them with real-life applications. Enables students to see the application of chemistry, microbiology, engineering, and other basic and applied sciences to the production, processing, preservation, evaluation,…

  1. Science: Secondary.

    ERIC Educational Resources Information Center

    Curriculum Review, 1980

    1980-01-01

    This article reviews and compares five recent secondary science texts: Addison-Wesley Life Science (Gr. 7-9); Prentice-Hall Life Science (Gr. 7-9); Scott Foresman Biology (Gr. 9-12); Biology: Living Systems (Gr. 10-12); and Biology: The Science of Life (Gr. 10-12). (SJL)

  2. Science Sacks

    ERIC Educational Resources Information Center

    Freudenberg, Kimberlee

    2012-01-01

    With the emphasis placed on standardized testing, science education has been squeezed out. As a physics teacher, the author knows the importance of building children's interest in science early in their school career and of providing practice in basic science skills and inquiry. In order to make more time for science at her sons' elementary…

  3. Science Matters

    ERIC Educational Resources Information Center

    Odell, Bill

    2005-01-01

    The spaces and structures used for undergraduate science often work against new teaching methods and fail to provide environments that attract the brightest students to science. The undergraduate science building often offers little to inspire the imaginations of young minds. The typical undergraduate science building also tends to work against…

  4. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat. PMID:27112279

  5. University Students' Conceptions about the Moon Phases. (Spanish Title: Concepciones de Estudiantes Universitários sobre Las Fases de la Luna.) Concepções de Estudantes Universitários sobre as Fases da Lua

    NASA Astrophysics Data System (ADS)

    de Fátima Oliveira Saraiva, Maria; da Silveira, Fernando Lang; Steffani, Maria Helena

    2011-07-01

    In this article we describe the development of a multiple choice test about lunar phases and analyze the results of its application to ten groups of Physics students at the UFRGS. During the improvement of the test, we noticed that the percentage of right answers about some concepts increased significantly when associated with the reformulation of the question, emphasizing the importance of being careful to avoid incorrect answers generated by unclear questions, and not by ignorance on the matter. We confirm the results of other studies that show that students have great difficulty to relate the Moon's phase with its position in the sky at given time. On the other hand, our results suggest that, in general, students of Physics understand the phenomenon of lunar phases better than the average of university students. En estese artículo se describe la elaboración de una prueba de opción múltiple sobre las fases de la Luna y se analizan los resultados de su aplicación en diez grupos de estudiantes de Física de UFRGS. Durante el mejoramiento de la prueba observamos que el porcentaje de aciertos creció considerablemente cuando considerada una nueva redacción de la pregunta, destacando el cuidado que se debe tomar a fin de evitar respuestas incorrectas generadas por preguntas poco claras y no a causa de la ignorancia de los estudiantes sobre el tema. Confirmamos los resultados de otros estudios que las mayores dificultades de los alumnos sobre el tema fases de la Luna están en relacionar la fase de la Luna con su posición en el cielo en determinado momento. Por otra parte, nuestros resultados sugieren que, en general, los estudiantes de la Física comprenden mejor el fenómeno de las fases lunares que el promedio de los estudiantes universitarios. Neste artigo descrevemos a elaboração de um teste de múltipla escolha sobre as fases da Lua e analisamos os resultados de sua aplicação em dez grupos de estudantes de Física da UFRGS. Durante o aprimoramento do teste notamos que a porcentagem de acertos a respeito de alguns conceitos teve um aumento significativo associado à reformulação da pergunta, ressaltando a importância de tomar cuidado para evitar respostas erradas geradas por perguntas pouco claras e não por ignorância do respondente sobre o assunto. Confirmamos os resultados de outros estudos de que as maiores dificuldades dos alunos sobre o tema Fases da Lua dizem respeito a relacionar a fase que a Lua apresenta com a sua posição no céu em determinada hora. Por outro lado, nossos resultados sugerem que, em geral, os estudantes de Física entendem melhor o fenômeno das fases lunares do que a média dos estudantes universitários.

  6. Biopolitical science.

    PubMed

    Arnhart, Larry

    2010-03-01

    This article develops a theoretical framework for biopolitical science as a science of political animals. This science moves through three levels of deep political history: the universal political history of the species, the cultural political history of the group, and the individual political history of animals in the group. To illustrate the particular application of biopolitical science, this essay shows how this science would help us to understand Abraham Lincoln's Emancipation Proclamation of January 1, 1863. PMID:20812796

  7. The enhancement of existing DES Maplet interface

    NASA Astrophysics Data System (ADS)

    Abdullah, Nur Lina; Mutalip, Rasidah Abdull; Abdullah, Kamilah

    2014-07-01

    This study pertains to the process of Data Encryption Standard, DES. DES consists of encryption and decryption processes linked with mathematical elements such as algebra and number theory. Preliminary, studies revealed that most of mathematics students face a problem in understanding the complicated process of DES. In modern learning methods, learning environment becomes more interesting with the use of computer and a variety of mathematical software packages. Several mathematical softwares such as Maple, Mathematica, Mathlab and Sage were developed in order to fulfill the specific calculation requirements. Correspondingly, motivated from that, this study incorporated with Maple to enhance the existing DES Maplet interface to be more interactive and user-friendly compared to the original version.

  8. VizieR Online Data Catalog: Galaxies in X-ray clusters with DES. I. Stellar mass (Zhang+, 2016)

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Miller, C.; McKay, T.; Rooney, P.; Evrard, A. E.; Romer, A. K.; Perfecto, R.; Song, J.; Desai, S.; Mohr, J.; Wilcox, H.; Bermeo-Hernandez, A.; Jeltema, T.; Hollowood, D.; Bacon, D.; Capozzi, D.; Collins, C.; Das, R.; Gerdes, D.; Hennig, C.; Hilton, M.; Hoyle, B.; Kay, S.; Liddle, A.; Mann, R. G.; Mehrtens, N.; Nichol, R. C.; Papovich, C.; Sahlen, M.; Soares-Santos, M.; Stott, J.; Viana, P. T.; Abbott, T.; Abdalla, F. B.; Banerji, M.; Bauer, A. H.; Benoit-Levy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Carnero Rosell, A.; Castander, F. J.; Diehl, H. T.; Doel, P.; Cunha, C. E.; Eifler, T. F.; Fausti Neto, A.; Fernandez, E.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gaztanaga, E.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Maia, M. A. G.; Makler, M.; Marshall, J. L.; Martini, P.; Miquel, R.; Ogando, R.; Plazas, A. A.; Roodman, A.; Rykoff, E. S.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla, I.; Smith, R. C.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Tucker, D.!; Vikram, V.; da Costa, L. N.

    2016-03-01

    The Dark Energy Survey (DES) is a ground-based optical survey that uses the wide-field DECam camera mounted on the 4m Blanco telescope to image 5000deg2 of the southern hemisphere sky (Sanchez et al. 2010JPhCS.259a2080S). The paper is based on 200deg2 DES Science Verification (SV) data. This data set was taken during the 2012B observing season before the main survey (Diehl et al. 2014SPIE.9149E..0VD) began. (1 data file).

  9. Science Fiction and Science Education.

    ERIC Educational Resources Information Center

    Cavanaugh, Terence

    2002-01-01

    Uses science fiction films such as "Jurassic Park" or "Anaconda" to teach science concepts while fostering student interest. Advocates science fiction as a teaching tool to improve learning and motivation. Describes how to use science fiction in the classroom with the sample activity Twister. (YDS)

  10. Caracterisation des proprietes acoustiques des materiaux poreux a cellules ouvertes et a matrice rigide ou souple

    NASA Astrophysics Data System (ADS)

    Salissou, Yacoubou

    L'objectif global vise par les travaux de cette these est d'ameliorer la caracterisation des proprietes macroscopiques des materiaux poreux a structure rigide ou souple par des approches inverses et indirectes basees sur des mesures acoustiques faites en tube d'impedance. La precision des approches inverses et indirectes utilisees aujourd'hui est principalement limitee par la qualite des mesures acoustiques obtenues en tube d'impedance. En consequence, cette these se penche sur quatre problemes qui aideront a l'atteinte de l'objectif global precite. Le premier probleme porte sur une caracterisation precise de la porosite ouverte des materiaux poreux. Cette propriete en est une de passage permettant de lier la mesure des proprietes dynamiques acoustiques d'un materiau poreux aux proprietes effectives de sa phase fluide decrite par les modeles semi-phenomenologiques. Le deuxieme probleme traite de l'hypothese de symetrie des materiaux poreux selon leur epaisseur ou un index et un critere sont proposes pour quantifier l'asymetrie d'un materiau. Cette hypothese est souvent source d'imprecision des methodes de caracterisation inverses et indirectes en tube d'impedance. Le critere d'asymetrie propose permet ainsi de s'assurer de l'applicabilite et de la precision de ces methodes pour un materiau donne. Le troisieme probleme vise a mieux comprendre le probleme de transmission sonore en tube d'impedance en presentant pour la premiere fois un developpement exact du probleme par decomposition d'ondes. Ce developpement permet d'etablir clairement les limites des nombreuses methodes existantes basees sur des tubes de transmission a 2, 3 ou 4 microphones. La meilleure comprehension de ce probleme de transmission est importante puisque c'est par ce type de mesures que des methodes permettent d'extraire successivement la matrice de transfert d'un materiau poreux et ses proprietes dynamiques intrinseques comme son impedance caracteristique et son nombre d'onde complexe. Enfin, le quatrieme probleme porte sur le developpement d'une nouvelle methode de transmission exacte a 3 microphones applicable a des materiaux ou systemes symetriques ou non. Dans le cas symetrique, on montre que cette approche permet une nette amelioration de la caracterisation des proprietes dynamiques intrinseques d'un materiau. Mots cles. materiaux poreux, tube d'impedance, transmission sonore, absorption sonore, impedance acoustique, symetrie, porosite, matrice de transfert.

  11. Profil pidmiologique des tumeurs malignes primitives des glandes salivaires : propos de 154 cas

    PubMed Central

    Setti, Khadija; Mouanis, Mohamed; Moumni, Abdelmounim; Maher, Mostafa; Harmouch, Amal

    2014-01-01

    Introduction Les tumeurs des glandes salivaires sont des tumeurs rares reprsentant 3 5% des tumeurs de la tte et du cou. La classification de l'OMS 2005 distingue les tumeurs pithliales, les tumeurs msenchymateuses, les tumeurs hmatologiques et les tumeurs secondaires. Mthodes Notre travail consiste en une tude rtrospective ralise sur une priode de 10 ans allant de janvier 2002 janvier 2012. Les critres d'inclusion taient: l'ge, le sexe, le sige de la tumeur et le type histologique. Rsultats L'incidence annuelle des tumeurs malignes primitives des glandes salivaires dans notre srie tait de 15 cas par an. Cent cinquante quatre cas de tumeurs malignes primitives des glandes salivaires ont t colligs sans prdominance de sexe (78 femmes (50,6%) et 76 hommes (49,4%)). La moyenne d'ge tait de 60 ans avec des extrmes de 4 et 83 ans et un pic de frquence entre 51et 70 ans. Deux tiers des cas (65%) avaient une localisation au niveau des glandes principales avec 66 cas au niveau de la parotide (43%) et 34 cas au niveau de la glande sous maxillaire (22%). Cinquante quatre patients avaient une tumeur maligne des glandes salivaires accessoires (35%) dont 61% au niveau du palais. Aucun cas de tumeur maligne de la glande sublinguale n'a t recens dans notre tude. Le type histologique prdominant dans notre srie tait le carcinome adnode kystique et retrouv chez 43 patients (27,9%), suivi de l'adnocarcinome sans autre indication chez 37 patients (24%) puis du carcinome mucopidermode chez 16 patients (10,4%) et de l'adnocarcinome polymorphe de bas grade galement chez 16 patients (10. 4%). Conclusion Les tumeurs malignes des glandes salivaires reprsentent un ensemble htrogne de maladies de caractrisation complexe et de frquence variable. PMID:25120861

  12. The king's animals and the king's books: the illustrations for the Paris Academy's Histoire des animaux.

    PubMed

    Guerrini, Anita

    2010-07-01

    This essay explores the place of natural philosophy among the patronage projects of Louis XIV, focusing on the Mémoires pour servir a l'histoire naturelle des animaux (or Histoire des animaux) of the 1670s, one of a number of works of natural philosophy to issue from Louis XIV's printing house. Questions particular to the Histoire des animaux include the interaction between text and image, the credibility and authority of images of exotic animals, and the relationship between comparative anatomy and natural history, and between human and animal anatomy. At the same time that the Histoire des animaux contributed to Jean-Baptiste Colbert's management of patronage and of Louis's image, it was a work of natural philosophy, representing the collaborative efforts of the new Paris Academy of Sciences. It examined natural history and comparative anatomy in new ways, and its illustrations broke new ground in their depiction of animals in a natural setting. However, the lavishly formatted books were presentation volumes and did not gain wide circulation until their republication in 1733. Sources consulted include Colbert's manuscript memoires on the royal printers and engravers. PMID:20853816

  13. L'effet des deformations plastiques severes sur les proprietes d'hydruration du magnesium

    NASA Astrophysics Data System (ADS)

    Lang, Julien

    Le travail de recherche effectue durant mon projet de maitrise en physique a l'Universite du Quebec a Trois-Rivieres dans les laboratoires de l'Institut de Recherche sur l'Hydrogene etait de comparer l'effet du laminage a froid de la poudre de MgH2 avec celui du broyage mecanique. Nous avons etudie cette nouvelle technique en utilisant un laminoir vertical concu specialement pour laminer de la poudre. Nous avons lamine la poudre de MgH2 5, 25, 50 et 100 fois. La comparaison de la morphologie de la poudre de MgH 2 telle que recu du manufacturier et broye mecaniquement pendant 30 minutes avec celle de la poudre laminee ete faite a l'aide d'un microscope electronique a balayage. Nous avons par la suite mesure les proprietes de sorption d'hydrogene grace un appareil PCT de type Sievert. Nous avons aussi determine la structure cristalline par diffraction de rayons X. A partir de ces resultats, nous avons constate que le nombre optimal de laminages est de cinq et a les caracteristiques d'absorption/desorption d'hydrogene similaires a un broyage mecanique de 30 minutes. Nous avons aussi utilise les courbes de cinetiques d'absorption et de desorption d'hydrogene pour calculer l'etape limitative dans les reactions de sorption des echantillons lamines. Comme cinq laminages se font en environ 10 secondes, on voit que le laminage a froid est une technique plus interessante industriellement que le broyage mecanique a cause de l'important gain en temps et en energie.

  14. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1990

    1990-01-01

    Presented are 27 science activities for secondary school science instruction. Topic areas include microbiology, botany, biochemistry, genetics, safety, earthquakes, problem solving, electricity, heat, solutions, mechanics, quantum mechanics, flame tests, and molecular structure. (CW)

  15. Science Sleuths.

    ERIC Educational Resources Information Center

    Lilly, Sherril L.

    1989-01-01

    Describes a two-day forensic science course that is offered to eighth grade students enrolled in Science, Mathematics, and Technology Magnet Schools. Provides sample student activity sheets for the course. (Author/RT)

  16. Simple Science

    ERIC Educational Resources Information Center

    Cowens, John

    2006-01-01

    This brief article presents some quick and easy science experiments for those dreary winter days when classrooms need a pick-me-up. These seemingly easy science experiments will make a lasting impact on students.

  17. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1990

    1990-01-01

    Presented are 29 science activities for secondary school science instruction. Topic areas include botany, genetics, biochemistry, anatomy, entomology, molecular structure, spreadsheets, chemistry, mechanics, astronomy, relativity, aeronautics, instrumentation, electrostatics, quantum mechanics, and laboratory interfacing. (CW)

  18. Forensic Science

    ERIC Educational Resources Information Center

    Berry, Keith O.; Nigh, W. G.

    1973-01-01

    A course is described, which was given during an interim, with an enrollment of 41 students. The course involved an in-depth study of forensic science, involving students with the methodology of science. (DF)

  19. Science participation

    NASA Astrophysics Data System (ADS)

    Male high school students are more than 3 times as likely as females to choose a career in science and engineering (S&E), according to a new National Science Foundation study. The report on that study, "Women, Minorities and Persons with Disabilities in Science and Engineering: 1994," documents the different rates at which these groups participate in science and engineering and the factors that influence their choice of study and their success.

  20. Relaxometry in soil science

    NASA Astrophysics Data System (ADS)

    Schaumann, G. E.; Jaeger, F.; Bayer, J. V.

    2009-04-01

    NMR relaxometry is a sensitive, informative and promising method to study pore size distribution in soils as well as many kinds of soil physicochemical processes, among which are wetting, swelling or changes in the macromolecular status. Further, it is a very helpful method to study interactions between molecules in soil organic matter and it can serve to study the state of binding of water or organic chemicals to soil organic matter. The method of Relaxometry excite the nuclei of interest and their relaxation kinetics are observed. The relaxation time is the time constant of this first order relaxation process. Most applications of relaxometry concentrate on protons, addressing water molecules or H-containing organic molecules. In this context, 1H-NMR relaxometry may be used as an analysis method to determine water uptake characteristics of soils, thus gaining information about water distribution and mobility as well as pore size distribution in wet and moist samples. Additionally, it can also serve as a tool to study mobility of molecular segments in biopolymers. Principally, relaxometry is not restricted to protons. In soil science, relaxometry is also applied using deuterium, xenon and other nuclei to study pore size distribution and interactions. The relaxation time depends on numerous parameters like surface relaxivity, diffusion and interactions between nuclei as well as between nuclei and the environment. One- and two-dimensional methods address the relation between relaxation time and diffusion coefficients and can give information about the interconnectivity of pores. More specific information can be gained using field cycling techniques. Although proton NMR relaxometry is a very promising method in soil science, it has been applied scarcely up to now. It was used to assess changes in molecular rigidity of humic substances. A very recent study shows the potential of NMR relaxometry to assess the pore size distribution of soils in a fast and non-destructive way. Recent studies investigated wetting and swelling processes in soil samples, as well as the formation of microbial biofilms in soil the formation. This contribution gives an overview of current applications and the potential of NMR relaxometry in soil science with special emphasis on proton NMR relaxometry. References Bird, N.R.A., Preston, A.R., Randall, E.W., Whalley, W.R. & Whitmore, A.P. 2005. Measurement of the size distribution of water-filled pores at different matric potentials by stray field nuclear magnetic resonance. 56, 135-143. Bryar, T.R. & Knight, R.J. 2002. Sensitivity of Nuclear Magnetic Resonance Relaxation Measurements to Changing Soil Redox Conditions. Geophysical Research Letters, 29, 50/1-50/4. Conte, P., Spaccini, R. & Piccolo, A. 2006. Advanced CPMAS-13C NMR techniques for molecular characterization of size-separated fractions from a soil humic acid. Analytical and Bioanalytical Chemistry, 386, 382-390. Gunasekara, A.S., Simpson, M.I. & Xing, B. 2003. Identification and characterization of sorption domains in soil organic matter using strucuturally modified humic acids. Environmental Science & Technology, 37, 852-858. Jaeger, F., Grohmann, E., Boeckelmann, U. & Schaumann, G.E. 2006. Microbial effects on 1H NMR Relaxometry in soil samples and glass bead reactors. In Humic Substances - Linking Structure to Functions. Proceedings of the 13th Meeting of the International Humic Substances Societyin Karlsruhe eds. F.H. Frimmel & G. Abbt-Braun), pp. 929-932. Universität Karlsruhe, Karlsruhe. Hurraß, J. & Schaumann, G.E. 2007. Hydration kinetics of wettable and water repellent soil samples. Soil Science Society of America Journal, 71, 280-288. Jaeger, F., Grohmann, E. & Schaumann, G.E. 2006. 1H NMR Relaxometry in natural humous soil samples: Insights in microbial effects on relaxation time distributions. Plant and Soil, 280, 209-222. Jaeger, F., Rudolph, N., Lang, F. & Schaumann, G.E. 2008. Effects of soil solution's constituents on proton NMR relaxometry of soil samples. Soil Science Society of America Journal, 72, 1694-1707. Jaeger, F., Bowe, S. & Schaumann, G.E. in preparation. Evaluation of 1H NMR relaxometry for the assessment of pore size distribution in soil samples. European Journal of Soil Science. Jähnert, S., Vaca Chavez, F., Schaumann, G.E., Schreiber, A., Schönhoff, M. & Findenegg, G.H. 2008. Melting and freezing of water in cylindrical silica nanopores. Physical Chemistry Chemical Physics, 39, 6039-6051. Schaumann, G.E., Hurraß, J., Müller, M. & Rotard, W. 2004. Swelling of organic matter in soil and peat samples: insights from proton relaxation, water absorption and PAH extraction. In Humic Substances: Nature's Most Versatile Materials eds. E.A. Ghabbour & G. Davies), pp. 101-117. Taylor and Francis, Inc., New York. Schaumann, G.E., Hobley, E., Hurraß, J. & Rotard, W. 2005. H-NMR Relaxometry to monitor wetting and swelling kinetics in high organic matter soils. Plant and Soil, 275, 1-20. Schaumann, G.E. & Bertmer, M. 2008. Do water molecules bridge soil organic matter molecule segments? European Journal of Soil Science, 59, 423-429. Todoruk, T.R., Langford, C.H. & Kantzas, A. 2003. Pore-Scale Redistribution of Water during Wetting of Air-Dried Soils As Studied by Low-Field NMR Relaxometry. Environmental Science and Technology, 37, 2707-2713. Todoruk, T.R., Litvina, M., Kantzas, A. & Langford, C.H. 2003. Low-Field NMR Relaxometry: A Study of Interactions of Water with Water-Repellant Soils. Environmental Science and Technology, 37, 2878-2882. Van As, H. & van Dusschoten, D. 1997. NMR methods for imaging of transport processes in micro-porous systems. Geoderma, 80, 389-403. Van As, H. & Lens, P. 2001. Use of 1H NMR to study transport processes in porous biosystems. Journal of Industrial Microbiology & Biotechnology, 26, 43-52.

  1. Prendre le virage des partenariats.

    PubMed

    Sebestyen, Norma; Sulatycky, Ron; Rondos, Spyro; Davis, Sheila

    2015-11-01

    Deux projets démontrent que la mise en œuvre de données colligées sur le terrain peut contribuer à régler des problèmes dans le milieu de la santé pour favoriser de meilleurs résultats et de plus grandes efficiences. Dans le premier exemple, une vaste coalition de partenaires publics et privés de l'Alberta recourt aux techniques de mesures améliorées et à la méthodologie du Triple objectif pour améliorer les résultats cliniques de populations de cas complexes et lourds du quartier Eastwood d'Edmonton. On espère que les conclusions novatrices qui en sont tirées seront adaptées à d'autres régions de la province. Dans le deuxième exemple, la Childhood Obesity Foundation s'associe à Merck au Canada et à Ayogo (une société de thérapies numériques située à Vancouver) et utilise le concept novateur de la « ludification » pour mobiliser les jeunes de plus en plus sédentaires du Canada et modifier leurs comportements. PMID:26482219

  2. Chemical effects in 11-year solar cycle simulations with the Freie Universität Berlin Climate Middle Atmosphere Model with online chemistry (FUB-CMAM-CHEM)

    NASA Astrophysics Data System (ADS)

    Langematz, Ulrike; Grenfell, J. Lee; Matthes, Katja; Mieth, Peter; Kunze, Markus; Steil, Benedikt; Brühl, Christoph

    2005-07-01

    The impact of 11-year solar cycle variations on stratospheric ozone (O3) is studied with the Freie Universität Berlin Climate Middle Atmosphere Model with interactive chemistry (FUB-CMAM-CHEM). To consider the effect of variations in charged particle precipitation we included an idealized NOx source in the upper mesosphere representing relativistic electron precipitation (REP). Our results suggest that the NOx source by particles and its transport from the mesosphere to the stratosphere in the polar vortex are important for the solar signal in stratospheric O3. We find a positive dipole O3 signal in the annual mean, peaking at 40-45 km at high latitudes and a negative O3 signal in the tropical lower stratosphere. This is similar to observations, but enhanced due to the idealized NOx source and at a lower altitude compared to the observed minimum. Our results imply that this negative O3 signal arises partly via chemical effects.

  3. Unterstützung der IT-Service-Management-Prozesse an der Technischen Universität München durch eine Configuration-Management-Database

    NASA Astrophysics Data System (ADS)

    Knittl, Silvia

    Hochschulprozesse in Lehre und Verwaltung erfordern durch die steigende Integration und IT-Unterstützung ein sogenanntes Business Alignment der IT und damit auch ein professionelleres IT-Service-Management (ITSM). Die IT Infrastructure Library (ITIL) mit ihrer Beschreibung von in der Praxis bewährten Prozessen hat sich zum de-facto Standard im ITSM etabliert. Ein solcher Prozess ist das Konfigurationsmanagement. Es bildet die IT-Infrastruktur als Konfigurationselemente und deren Beziehungen in einem Werkzeug, genannt Configuration Management Database (CMDB), ab und unterstützt so das ITSM. Dieser Bericht beschreibt die Erfahrungen mit der prototypischen Einführung einer CMDB an der Technischen Universität München.

  4. Dramatic Science

    ERIC Educational Resources Information Center

    McGregor, Debbie; Precious, Wendy

    2010-01-01

    The setting: the science classroom. The characters: you and your students. The scene: Your students acting out scientific discoveries, modeling a frog's life cycle, mimicking the transition from liquid to solid. This is "dramatic science", a teaching approach that uses acting techniques to explore and develop young children's ideas about science.…

  5. Watershed Science.

    ERIC Educational Resources Information Center

    Green, Tom

    1996-01-01

    Presents activities from an interdisciplinary project studying local watersheds that incorporate a broad spectrum of disciplines including science, math, geography, English, computer science, and political science. Enables students to understand how precipitation changes chemically as it interacts with the soils and human-altered landscape as it…

  6. Science Facilities

    ERIC Educational Resources Information Center

    Butin, Dan W.; Biehle, James T.; Motz, LaMoine L.; West, Sandra S.

    2009-01-01

    The National Research Council's "National Science Education Standards" call for science education to be "developmentally appropriate, interesting, and relevant to students' lives, emphasize student understanding through inquiry, and be connected with other school subjects." This description captures the three major trends in science education…

  7. Safer Science

    ERIC Educational Resources Information Center

    Roy, Ken

    2011-01-01

    This column provides best safety practices for the science classroom and laboratory. In this month's issue, pregnancy policy in the laboratory is discussed. One can't ignore the fact that student and faculty pregnancies--and the resulting potential hazards in the science laboratory--exist at the high school level. Science teachers need to be…

  8. Safer Science

    ERIC Educational Resources Information Center

    Roy, Ken

    2011-01-01

    This column provides best safety practices for the science classroom and laboratory. In this month's issue, pregnancy policy in the laboratory is discussed. One can't ignore the fact that student and faculty pregnancies--and the resulting potential hazards in the science laboratory--exist at the high school level. Science teachers need to be

  9. Sublime Science

    ERIC Educational Resources Information Center

    Girod, Mark

    2007-01-01

    One of the shortcomings in most efforts to integrate art and science is that many people have a shallow understanding of art, which inevitably leads to shallow connections between art and science. Coloring drawings of planets, building sculptures of volcanoes, and decorating scientific diagrams are fine activities, but they do not link science and…

  10. Dramatic Science

    ERIC Educational Resources Information Center

    McGregor, Debbie; Precious, Wendy

    2010-01-01

    The setting: the science classroom. The characters: you and your students. The scene: Your students acting out scientific discoveries, modeling a frog's life cycle, mimicking the transition from liquid to solid. This is "dramatic science", a teaching approach that uses acting techniques to explore and develop young children's ideas about science.

  11. Science First.

    ERIC Educational Resources Information Center

    Strycker, Jan Adkins

    1995-01-01

    Describes a teacher's efforts to put science first in the classroom. Discusses changing the place of science on the schedule and presents an activity to engage student interest. Concludes that a difference in teacher attitude towards science motivates students to learn. (NB)

  12. Early science education and astronomy

    NASA Astrophysics Data System (ADS)

    Wilgenbus, David; Léna, Pierre

    2011-06-01

    Inquiry-based science education is currently receiving a consensus as a pedagogy to teach science at primary and middle school levels, with the goal to reach all children and youngsters, no matter what their future professional choices will be. By the same token, it also greatly increases the fraction of the school population in which future technicians, engineers and sciences could be recruited for further training. La main à la pâte is the name of the action undertaken by the French Académie des Sciences to develop inquiry in France, and then in many collaborating countries. The focus is on science as a whole, and not on particular disciplines such as physics, biology, and so on, since it is the understanding of scientific method and use of evidence which is at the heart of inquiry. Yet, astronomy is offering so many opportunities to demonstrate the scientific method that La main à la pâte has developed a number of inquiry activities in this field, which are presented here, such as Measuring the Earth, Calendars and cultures, the use of One Laptop per Child for Moon observations, etc.

  13. Early science books and their women translators

    NASA Astrophysics Data System (ADS)

    Badilescu, Simona

    1998-12-01

    By the late eighteenth century, women wrote books popularizing the major scientific advances of the times. From even an earlier stage, women translated popular science books, many written especially for the ``use of the Ladies.'' From Aphra Behn's translation of Fontenelle's famous Entretiens sur la Pluralité des Mondes in 1686 to Mary Somerville's 1831 lucid exposition in English of Laplace's well-known book, The Mechanism of the Heavens, translation moved gradually toward professional scientific exposition. Who were these women and what sparked their interest in science? How had they acquired the knowledge necessary to translate science books? The aim of this article is to shed some light on a little known area of women's activities-the translation of science books-and to show their contribution to the diffusion of the scientific knowledge.

  14. Science Toys for Science Education.

    ERIC Educational Resources Information Center

    Raw, Isaias

    1982-01-01

    The absence of "hands-on" experiences with science equipment in schools stimulated the production of science kits for children. Thirty years later this enterprise has become a national institution in Brazil with a proud history of effecting change in the teaching of science throughout this country. (Author/JN)

  15. Science Squared: Teaching Science Visually.

    ERIC Educational Resources Information Center

    Paradis, Olga; Savage, Karen; Judice, Michelle

    This paper describes a collection of novel ideas for bulletin board displays that would be useful in supplementing science classroom instruction. Information on women and minorities in science; science concepts in everyday activities such as nutrition, baseball, and ice cream-making; and various holidays and celebratory events is included. Each…

  16. U3A: A French Model for the Later Years.

    ERIC Educational Resources Information Center

    Radcliffe, David

    The university for the third age (U3A) began in 1973 when a professor organized a summer program for retired persons at the Universite des Sciences Socialies, Toulouse, France. The Toulouse model included a weekly public lecture on a major topic of concern for older persons, discussion groups, seminars, and recreational facilities, taking…

  17. Observatoire de Lyon

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The Observatoire de Lyon is a laboratory of Université Claude Bernard Lyon1, under the authority of the INSTITUT NATIONAL DES SCIENCES DE L'UNIVERS. It constitutes the Centre de Recherche astrophysique de Lyon together with the astrophysics group of the École Normale Supérieure de Lyon....

  18. Profil epidemiologique des brulures d'enfants admis au Centre National des Brules, Maroc

    PubMed Central

    Zahid, A.; Atannaz, J.; Alaoui, M.; Rafik, A.; Ezzoubi, M.; Diouri, M.; Chlihi, A.; Bahechar, N.; Boukind, E.H.

    2011-01-01

    Summary Ce travail rtrospectif analyse les particularits pidmiologiques de 543 cas de brlures d'enfants, reprsentant 45,7% des admissions de notre centre, en vue de dterminer les lments pouvant contribuer renforcer la prvention, qui reste le traitement de choix de cette pathologie. La moyenne d'ge est de 4,25 ans avec une prdilection pour la tranche d'ge d'un cinq ans, avec 42,5% des cas. Une atteinte masculine est retrouve dans 63,5% des cas. La brlure survient domicile dans 85,1% et accidentellement dans 95% des cas. Les brlures thermiques reprsentent 96,5% des causes domines par les liquides dans 69,3% des cas. La surface cutane brle est ? 20% dans 52,3%. La brlure intresse essentiellement les membres suprieurs (79,1%). 56,8% des enfants sont transfrs par d'autres hpitaux et le dlai de prise en charge hospitalire est suprieur 6 heures dans 65,5%. Le taux de mortalit a t de 13,2%. PMID:22639559

  19. 75 FR 63714 - Drawbridge Operation Regulation; Des Allemands Bayou, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Des Allemands Bayou, LA AGENCY: Coast... Burlington Northern Santa Fe Railway swing bridge across Des Allemands Bayou, mile 14.0, in St. Charles and... INFORMATION: The Burlington Northern Santa Fe Railway swing span drawbridge across Bayou Des Allemands,...

  20. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Des Allemands Bayou. 117.439... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The draw of the S631 bridge, mile 13.9 at Des Allemands, shall open on signal if at least four hours notice...

  1. Reading Science

    ERIC Educational Resources Information Center

    Carlson, Kenneth

    2005-01-01

    Reading the average science textbook, one is struck with a question: Why would people devote their lives to the study of a subject as dry as the Sahara Desert? Students in science classes only need to be let in on the great secret of science. It is fun and full of the stuff in page-turner novels--intrigue, mystery, romance, and sometimes just dumb…

  2. Deconstructing science

    NASA Astrophysics Data System (ADS)

    Trifonas, Peter Pericles

    2012-12-01

    In this paper I expand on the premises of Jesse Bazzul's thesis in his paper, Neoliberal ideology, global capitalism, and science education: engaging the question of subjectivity, exploring the implications of the ideologies within the culturally emerging logic of science exposes the incommensurability of intents and purposes in its methods and epistemology. I argue that science needs to acknowledge the subjectivity at its core to make space for non-absolute agents and new fields of study.

  3. Etude numerique et experimentale de la reponse vibro-acoustique des structures raidies a des excitations aeriennes et solidiennes

    NASA Astrophysics Data System (ADS)

    Mejdi, Abderrazak

    Les fuselages des avions sont generalement en aluminium ou en composite renforces par des raidisseurs longitudinaux (lisses) et transversaux (cadres). Les raidisseurs peuvent etre metalliques ou en composite. Durant leurs differentes phases de vol, les structures d'avions sont soumises a des excitations aeriennes (couche limite turbulente : TBL, champs diffus : DAF) sur la peau exterieure dont l'energie acoustique produite se transmet a l'interieur de la cabine. Les moteurs, montes sur la structure, produisent une excitation solidienne significative. Ce projet a pour objectifs de developper et de mettre en place des strategies de modelisations des fuselages d'avions soumises a des excitations aeriennes et solidiennes. Tous d'abord, une mise a jour des modeles existants de la TBL apparait dans le deuxieme chapitre afin de mieux les classer. Les proprietes de la reponse vibro-acoustique des structures planes finies et infinies sont analysees. Dans le troisieme chapitre, les hypotheses sur lesquelles sont bases les modeles existants concernant les structures metalliques orthogonalement raidies soumises a des excitations mecaniques, DAF et TBL sont reexamines en premier lieu. Ensuite, une modelisation fine et fiable de ces structures est developpee. Le modele est valide numeriquement a l'aide des methodes des elements finis (FEM) et de frontiere (BEM). Des tests de validations experimentales sont realises sur des panneaux d'avions fournis par des societes aeronautiques. Au quatrieme chapitre, une extension vers les structures composites renforcees par des raidisseurs aussi en composites et de formes complexes est etablie. Un modele analytique simple est egalement implemente et valide numeriquement. Au cinquieme chapitre, la modelisation des structures raidies periodiques en composites est beaucoup plus raffinee par la prise en compte des effets de couplage des deplacements planes et transversaux. L'effet de taille des structures finies periodiques est egalement pris en compte. Les modeles developpes ont permis de conduire plusieurs etudes parametriques sur les proprietes vibro-acoustiques des structures d'avions facilitant ainsi la tache des concepteurs. Dans le cadre de cette these, un article a ete publie dans le Journal of Sound and Vibration et trois autres soumis, respectivement aux Journal of Acoustical Society of America, International Journal of Solid Mechanics et au Journal of Sound and Vibration Mots cles : structures raidies, composites, vibro-acoustique, perte par transmission.

  4. Note des Éditeurs scientifiques

    NASA Astrophysics Data System (ADS)

    Averbuch, P.

    Cette série d'articles est une revue de résultats expérimentaux sur différents "fluides" moléculaires, dans lesquels la cohésion est due à des forces de Van der Waals et à des liaisons hydrogène, l'eau étant un de ces fluides. Ces résultats sont présentés de façon à justifier expérimentalement un modèle original, non extensif, des propriétés de ces fluides, et l'ensemble se présente sous la forme de trois articles décrivant le modèle, suivis chacun par un article le comparant aux résultats expérimentaux publiés par de nombreux auteurs. Le caractère non extensif des propriétés physiques des fluides est choquant, contraire à beaucoup d'idées établies, il semble n'avoir en sa faveur qu'un argument, la comparaison avec un nombre de résultats expérimentaux assez grand pour que l'effet du hasard soit difficilement soupçonnable. En particulier, les écarts entre des résultats de mesures faits par des auteurs différents dans des conditions différentes sont expliqués, le sérieux et la compétence des différents expérimentateurs ne sont plus mis en doute : mais l'interprétation de ces résultats avec un modèle extensif non adapté est seule mise en cause. Les modèles extensifs étant utilisés systématiquement, au delà des expériences de physiciens, dans les calculs d'ingénieurs, et dans la modélisation d'appareils qui fonctionnent et de phénomènes naturels observés par tout le monde, il fallait expliquer pourquoi on pouvait renoncer à l'extensivité. Les raisons du succès pratique des modèles extensifs sont données, d'abord dans le cas des nématiques, puis dans celui des liquides ordinaires, et c'est ce qui rend l'ensemble cohérent, tant avec les mesures physiques fines qu'avec les observations quotidiennes. Il n'en reste pas moins que si l'interprétation donnée dans cette série d'articles est généralisable, une justification théorique du modèle utilisé devient nécessaire. Pour ce qui est des propriétés d'équilibre, une séparation de l'énergie libre en énergie libre de volume et en énergie libre de surface devrait donner les mêmes résultats ; par contre les choses deviennent troublantes dès que l'on passe aux coefficients de transport, c'est-à-dire à l'aspect macroscopique de la dynamique moléculaire. Il y a là un écart notable avec les conceptions courantes, ce qui rend très surprenante la lecture de ces articles. On peut mentionner la liste des problèmes théoriques posés par la description phénoménologique qui est celle de cette série d'articles : la généralisation de lois d'échelle en dehors de zones critiques n'est pas absolument nouvelle, par contre la simplicité des lois reliant l'exposant v à la température pose problème ; le sens des temps de relaxation utilisés est sans doute également à préciser. Enfin les modes considérés semblent n'intervenir dans les propriétés thermodynamiques que par un facteur par mode, comme si seulement l'énergie potentielle devait intervenir, les termes cinétiques ne participant pas vraiment aux transitions de phase. Tout cela pose donc problème, et l'on peut se demander si un pareil modèle peut être compatible avec tout ce qui est connu par ailleurs en physique statistique. Mais s'il rend bien compte de beaucoup de résultats expérimentaux, ce sont ces derniers qui seraient en difficulté avec la mécanique statistique. Il a donc semblé préférable de publier le modèle, sa justification expérimentale et de poser quelques problèmes, tant aux théoriciens, qui pourraient expliquer pourquoi un tel modèle rend compte de résultats observés, qu'aux expérimentateurs, qui pourraient reprendre certaines mesures, et délimiter le caractère plus ou moins général du modèle.

  5. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1987

    1987-01-01

    Contains 31 activities and experiments from the biological and physical sciences. Addresses such areas as reproduction, biotechnology, ecology, proteins, nitrates, aerosols, metal crystallinity, circuit boards, and photoswitching. (ML)

  6. Une recension des écrits concernant la réalité psychoaffective des femmes ayant une vulvodynie : Difficultés rencontrées et stratégies développées

    PubMed Central

    Cantin-Drouin, Maude; Damant, Dominique; Turcotte, Daniel

    2008-01-01

    HISTORIQUE : Au cours des trois dernières décennies, une attention grandissante a été portée à l’étude du syndrome de vulvodynie, soit un inconfort vulvaire chronique inexpliqué, éprouvé en l’absence de pathologie précisée. En plus d’avoir des répercussions physiques, l’expérience de la vulvodynie comporte une dimension psychosociale. OBJECTIF : Cet article vise à faire une recension des écrits sur la réalité psychoaffective des femmes qui éprouvent une vulvodynie. MÉTHODE : Une recherche documentaire basée sur une exploration systématique de textes présentant des résultats de recherche et recensés dans les principales banques de données en sciences sociales, dont Dissertation Abstracts, Current Contents et PsycINFO, a été réalisée. RÉSULTATS : Cette recension des écrits révèle, malgré la présence de certains résultats divergents, que les femmes ayant une vulvodynie affrontent souvent des difficultés identitaires et psychologiques, qui sont influencées notamment par les normes sociales de sexualité et de féminité. Pour composer avec ces difficultés, les femmes développent différentes stratégies visant à diminuer le stress occasionné par la douleur et à améliorer leur bien-être psychologique. CONCLUSION : Les difficultés relationnelles et psychologiques vécues par les femmes ayant une vulvodynie ne découlent pas seulement de la douleur physique, mais aussi du sens qu’elles lui accordent, souvent influencé par les discours sociaux sur l’hétérosexualité et la féminité. Il importe donc d’intervenir auprès des femmes en tenant compte de l’influence du contexte social tout en poursuivant le développement des connaissances sur les aspects psychosociaux de cette expérience. PMID:18592063

  7. Developpement des betons semi autoplacants a rheologie adaptee pour des infrastructures

    NASA Astrophysics Data System (ADS)

    Sotomayor Cruz, Cristian Daniel

    Au cours des dernières décennies, les infrastructures canadiennes et québécoises comportent plusieurs structures en béton armé présentant des problèmes de durabilité dus aux conditions climatiques sévères, à la mauvaise conception des structures, à la qualité des matériaux, aux types des bétons choisis, aux systèmes de construction ou à l'existence d'événements incontrôlables. En ce qui concerne le choix du béton pour la construction des infrastructures, une vaste gamme de béton divisée en deux principaux types peut être utilisée: le béton conventionnel vibré (BCV) et le béton autoplaçant (BAP). Dans le cas d'un BCV, la consolidation inadéquate par vibration a été un problème récurrent, occasionnant des dommages structuraux. Ceci a conduit à une réduction de la durabilité et à une augmentation du coût d'entretien et de réparation des infrastructures. Rien que l'utilisation d'un BAP a des avantages tels que l'élimination de la vibration, la réduction des coûts de main d'oeuvre et l'amélioration de la qualité des structures, néanmoins, le coût initial d'un BAP par rapport à un BCV ne permet pas encore de généraliser son utilisation dans l'industrie de la construction. Ce mémoire présente la conception d'une nouvelle gamme de béton semi-autoplaçant pour la construction des infrastructures (BSAP-I) exigeant une vibration minimale. Il s'agit de trouver un équilibre optimal entre la rhéologie et le coût initial du nouveau béton pour conférer une bonne performance structurale et économique aux structures. Le programme expérimental établi a premièrement permis d'évaluer la faisabilité d'utilisation des BSAP-I pour la mise en place des piliers d'une infrastructure de pont à Sherbrooke. En plus, l'utilisation d'un plan d'expériences a permis l'évaluation de trois paramètres de formulation sur les propriétés des mélanges de BSAP-I à l'état frais et durci. Finalement, l'évaluation de la performance des BSAP-I optimisés à travers une caractérisation complète des propriétés mécaniques et de la durabilité a été réalisée. A la suite de cette étude, les résultats obtenus nous permettent de conclure que : (1) L'utilisation d'un BSAP-I avec un gros granulat de 5 - 14 mm, des rapports E/L = 0,37 et S/G = 0,52 et une teneur en air de 6 à 9% a été possible en conférant un équilibre optimal fluidité / stabilité à l'état frais, ainsi qu'un niveau de thixotropie adéquate au chantier permettant d'optimiser la conception du coffrage des piliers de pont et de conférer des qualités de surfaces très acceptables de ces infrastructures. (2) La méthode adaptée pour l'essai L-Box contenant 2 barres et une vibration de 5 secondes a permis de bien caractériser la capacité de remplissage d'un BSAP-I. (3) L'utilisation d'un plan factoriel 23 a permis d'obtenir des modèles statistiques fiables, capables de prédire les propriétés rhéologiques à l'état frais et les résistances en compression des BSAP-I avec des dosages en liant entre 370 et 420 kg/m3, des rapports E/L entre 0,34 et 0,40 et S/G entre 0,47 et 0,53. (4) Des mesures de vitesse d'écoulement T40 d'un BSAP-I sont très semblables à celles d'un BAP. En plus, des valeurs T40 montrent une bonne corrélation linéaire avec celles de T400 mesurés dans la boîte L-Box. (5) À la frontière du BAP et du BCV, une bande rhéologique possédant un τ0 entre 30 et 320 Pa et un η entre 10 et 140 Pa.s a été trouvée pour la conception optimale des BSAP-I. (6) Les BSAP-I optimisés ont également conféré une très bonne performance à l'état frais, en permettant maintenir un bon équilibre entre la rhéologie et la stabilité dans le temps, lorsqu'on utilise une énergie de vibration minimale pour amorcer son écoulement. (7) À l'état durci Les BSAP-I ont conféré une bonne performance présentant des résistances mécaniques élevées et des niveaux négligeables de pénétration aux ions chlores, de perte de masse par écaillage et des attaques par le gel/dégel. (8) L'utilisation des ciments combinés possédant de la fumée de silice, du laitier et de la cendre volante ont permis améliorer le comportement rhéologique et minimiser le retrait par séchage des BSAP-I dans le temps. Mots-clés : Béton autoplaçant (BAP), capacité de remplissage, pression hydrostatique, rhéologie, seuil de cisaillement, thixotropie, maniabilité.

  8. Science Fairs for Science Literacy

    NASA Astrophysics Data System (ADS)

    Mackey, K. R.

    2014-12-01

    Science literacy is imperative for well informed civic and personal decision making, yet only a quarter of American adults are proficient enough in science to understand science stories reported in the popular press. Hands-on research increases confidence in and understanding of science. When guiding students in designing and conducting science fair projects, mentors can foster science literacy by helping students focus on three goals: (1) articulating hypotheses or questions, (2) designing feasible projects, and (3) learning to make and interpret graphs. These objectives introduce students to the methodological nature of scientific research and give them the tools to interpret scientific facts and data in order to make informed decisions for themselves and society.

  9. Etude theorique et experimentale des evaporateurs de dioxyde de carbone operant dans des conditions de givrage

    NASA Astrophysics Data System (ADS)

    Bendaoud, Adlane Larbi

    Les evaporateurs de refrigeration sont surtout du type tube a ailettes, appeles serpentins, et fonctionnent dans l'une des conditions suivantes: seche, humide ou avec formation de givre. Il a ete demontre que la formation du givre sur la paroi exterieure de l'echangeur engendre une surconsommation energetique a cause des operations de degivrage puisque 15 a 20% seulement de la chaleur produite sert au degivrage tandis que le reste est dissipee dans l'environnement [1]. Avec l'avenement des nouveaux refrigerants, moins nocifs envers l'environnement, l'industrie du froid se trouve penalisee du fait que peu ou pas de composantes mecaniques (compresseur, pompe, echangeur...etc.) adaptees sont disponibles [3]. Il s'agit pour la communaute des frigoristes de combler ce retard technologique en redeveloppant ces composantes mecaniques afin qu'elles soient adaptees aux nouveaux refrigerants. Dans cette optique, et afin de mieux comprendre le comportement thermique des evaporateurs au CO2 fonctionnant dans des conditions seches, qu'un groupe de chercheurs du CanmetENERGIE avaient lance, en 2000, un programme de R & D. Dans le cadre de programme un outil de simulation des evaporateurs au CO2 a ete developpe et un banc d'essai contenant une boucle secondaire de refrigeration utilisant le CO2 comme refrigerant a ete construit. Comme continuite de ce travail de recherche, en 2006 ce meme groupe de recherche a lance un nouveau projet qui consiste a faire une etude theorique et experimentale des evaporateurs au CO2 operants dans des conditions de givrage. Et, c'est exactement dans le cadre de ce projet que se positionne ce travail de these. Ce travail de recherche a ete entrepris pour mieux comprendre le comportement thermique et hydrodynamique des serpentins fonctionnant dans des conditions de givrage, l'effet des circuits de refrigerant ainsi que celui des parametres geometriques et d'operation. Pour cela, un travail theorique supporte par une etude experimentale a ete effectue. Dans la partie theorique, un modele traitant les aspects thermique, hydrodynamique et massique a ete elabore. Sur la base de ce modele a ete ecrit un programme informatique en langage FORTRAN 6.6. Il est base sur la discretisation du serpentin en volumes de controle, est entierement automatise et peut traiter des echangeurs de chaleur avec des circuits de refrigerant complexes pouvant avoir des entrees et sorties multiples ainsi que des bifurcations. La presence simultanee des trois phases thermodynamiques du refrigerant (liquide sous refroidi, fluide sature, vapeur surchauffee) dans le serpentin est aussi prise en charge. Le modele a ete valide pour un fonctionnement avec et sans formation de givre en utilisant des donnees experimentales disponibles dans la litterature et celles obtenues sur le banc d'essai de CanmetENERGIE. Celui-ci a ete mis a jour pour les besoins de la presente recherche et pour cela, un systeme de surchauffe et d'injection de la vapeur d'eau dans une enceinte a tres basse temperature a ete dimensionne, fabrique et installe. Un dispositif de visualisation de la formation de givre, ainsi qu'un equipement de mesure de la temperature, de la pression et de l'humidite relative de l'air ont aussi ete ajoutes. Une fois le modele valide, des simulations numeriques sur le serpentin avec et sans formation de givre ont ete effectuees. Un premier cas de base a servi comme reference pour d'autres cas pour lesquels une etude parametrique sur la geometrie et le fonctionnement a ete menee. Il a ete montre par rapport au cas de base que : 1. la diminution de la densite des ailettes sur des rangees specifiques du serpentin donne une surface minimale (Amin) plus grande, retardant ainsi l'obstruction totale du serpentin par le givre et permet donc un temps de fonctionnement plus grand et une frequence de degivrage plus faible. 2. une bonne configuration de circuit de refrigerant augmente le temps de fonctionnement du serpentin de 200 % et delivre une puissance frigorifique moyenne superieures de 20 % par rapport a celle du cas de base. 3. la diminution de la temperature de l'air a l'entree du serpentin entraine une diminution du temps de fonctionnement et augmente la frequence de degivrage alors que la diminution de l'humidite relative de l'air a l'entree augmente le temps de fonctionnement et reduis la frequence de degivrage. 4. le debit massique de l'air est un parametre tres important qu'il faut choisir et determiner avec beaucoup de soin afin de ne pas serieusement affecter le temps de fonctionnement du serpentin. Les resultats issus de ce travail de recherche ont fait l'objet de trois publications dans des revues internationales [4-6] et de deux presentations dans des conferences specialisees [7,8]. (Abstract shortened by UMI.)

  10. L'amelioration potentielle des sciages d'epinette noire en tenant compte des noeuds

    NASA Astrophysics Data System (ADS)

    Lemieux, Hugo

    Cette recherche a pour but de determiner l'amelioration potentielle de la resistance mecanique des sciages d'epinette noire. Un echantillon de billes a ete mesure afin de caracteriser les noeuds en surface. Un sous-echantillon a ete disseque afin de caracteriser les noeuds. Ces mesures ont servi dans un modele de debitage de billes et de classement des planches qui prend en compte les noeuds. Des simulations de sciage et de classement ont ete effectuees sur toutes les billes en faisant des rotations de celles-ci. Les simulations ont determine les positions qui donnent un meilleur et un pire rendement au niveau du classement. La moitie des billes a ensuite ete sciee par rapport a une meilleure position et l'autre moitie par rapport a la pire solution. Les sciages ont ete classes visuellement par rapport aux noeuds seulement et par rapport a tous les defauts. Ils ont ensuite ete testees a destruction. L'analyse a determine que les noeuds n'ont pas d'effet sur le classement visuel des sciages mais qu'ils ont eu un effet marque sur la resistance mecanique.

  11. Actes du colloque sur le bilinguisme, Universite de Neuchatel, 14/15 Septembre, 1981 (Proceedings of the Colloquium on Bilingualism, University of Neuchatel, September 14-15, 1981).

    ERIC Educational Resources Information Center

    TRANEL, 1982

    1982-01-01

    This issue contains proceedings of a colloquium on linguistics at the University of Neuchatel: (1) "Propositions epistemologiques pour une etude du bilinguisme (Epistemological Propositions for a Study of Bilingualism)," by B. Py; (2) "Comment on di ca? Prolegomenes a une etude de la composante semantique du langage des migrants (How Do You Say…

  12. Actes du colloque sur le bilinguisme, Universite de Neuchatel, 14/15 Septembre, 1981 (Proceedings of the Colloquium on Bilingualism, University of Neuchatel, September 14-15, 1981).

    ERIC Educational Resources Information Center

    TRANEL, 1982

    1982-01-01

    This issue contains proceedings of a colloquium on linguistics at the University of Neuchatel: (1) "Propositions epistemologiques pour une etude du bilinguisme (Epistemological Propositions for a Study of Bilingualism)," by B. Py; (2) "Comment on di ca? Prolegomenes a une etude de la composante semantique du langage des migrants (How Do You Say

  13. The "Conservatoire National des Arts et Metiers"

    ERIC Educational Resources Information Center

    Kuhn, Gerard

    2004-01-01

    The overall mission of the Conservatoire national des arts et metiers--(CNAM) [National Conservatory of Industrial Arts and Trades] is outlined. One of its centers, the "Centre national de l'entrepreneuriat"--(CNE) [National Center for Entrepreneurship] is described in greater detail. In particular, this center offers various services, notably…

  14. More About Spurious Numerical Solutions Of DEs

    NASA Technical Reports Server (NTRS)

    Yee, H. C.; Sweby, P. K.

    1995-01-01

    Paper discusses reliability of time-dependent approach to numerical solution of nonlinear differential equations (DEs) that describe steady-state behaviors of physical systems. Time-dependent approach followed in related study described in "Spurious Numerical Solutions of Differential Equations" (ARC-13209).

  15. The science in social science

    PubMed Central

    Bernard, H. Russell

    2012-01-01

    A recent poll showed that most people think of science as technology and engineering—life-saving drugs, computers, space exploration, and so on. This was, in fact, the promise of the founders of modern science in the 17th century. It is less commonly understood that social and behavioral sciences have also produced technologies and engineering that dominate our everyday lives. These include polling, marketing, management, insurance, and public health programs. PMID:23213222

  16. The void comprises everything - natural philosophy and science in Otto von Guericke's proof of existence of empty and infinite space. (German Title: Alles umfasst es, das Nichts - Naturphilosophie und Naturwissenschaft im Existenzbeweis des leeren und unendlichen Weltraums bei Otto von Guericke)

    NASA Astrophysics Data System (ADS)

    Gabriel, Peter

    Otto von Guericke showed in his book Experimenta nova (ut vocantur) Magdeburgica de vacuo spatio that space is an infinite void. This contribution illustrates how Guericke mixed natural philosophy and natural science in his argumentation with each other.

  17. The sciences of science communication

    PubMed Central

    Fischhoff, Baruch

    2013-01-01

    The May 2012 Sackler Colloquium on “The Science of Science Communication” brought together scientists with research to communicate and scientists whose research could facilitate that communication. The latter include decision scientists who can identify the scientific results that an audience needs to know, from among all of the scientific results that it would be nice to know; behavioral scientists who can design ways to convey those results and then evaluate the success of those attempts; and social scientists who can create the channels needed for trustworthy communications. This overview offers an introduction to these communication sciences and their roles in science-based communication programs. PMID:23942125

  18. "Children's Science"

    ERIC Educational Resources Information Center

    Milne, Ian

    2007-01-01

    The revamped New Zealand curriculum emphasises "scientific literacy for all students" and provides teachers with an opportunity to promote science as an integral element of the primary school curriculum. Exploring and explaining the natural world in primary science can provide authentic contexts for the development of knowledge, skills, and…

  19. Soundsational Science

    ERIC Educational Resources Information Center

    Carrier, Sarah J.; Scott, Catherine Marie; Hall, Debra T.

    2012-01-01

    The science of sound helps students learn that sound is energy traveling in waves as vibrations transfer the energy through various media: solids, liquids, and gases. In addition to learning about the physical science of sound, students can learn about the sounds of different animal species: how sounds contribute to animals' survival, and how…

  20. Personalizing Science

    ERIC Educational Resources Information Center

    Danielowich, Robert M.

    2014-01-01

    Science teachers are aware of many social issues that intersect with science. These socio-scientific issues (SSIs) are "open-ended problems without clear-cut solutions [that] can be informed by scientific principles, theories, and data, butcannot be fully determined by [them]" (Sadler 2011, p. 4). This article describes the SSI lessons

  1. Talking Science

    ERIC Educational Resources Information Center

    Shwartz, Yael; Weizman, Ayelet; Fortus, David; Sutherland, LeeAnn; Merrit, Joi; Krajcik, Joe

    2009-01-01

    Science is a social process--one that involves particular ways of talking, reasoning, observing, analyzing, and writing, which often have meaning only when shared within the scientific community. Discussions are one of the best ways to help students learn to "talk science" and construct understanding in a social context. Since inquiry is an…

  2. Science Alive!

    ERIC Educational Resources Information Center

    Tally-Foos, Kay

    2005-01-01

    At the authors' school, as in many places, she struggles with making science a meaningful part of her students' lives. The teachers are working under state mandates to prepare students for reading and mathematics tests in third, fourth, and fifth grades. Often, this relegates science and social studies to a distant back burner. In an effort to

  3. Why Science?

    ERIC Educational Resources Information Center

    Primary Science Review, 2006

    2006-01-01

    This article presents people from many walks of life, including some well-known names, who share their views about science. Adam Hart-Davis, who studied chemistry at university and is now an author, photographer, historian and broadcaster, explains why science cannot start too soon. Lis Nairn, Manager, Stratigraphy, with Fugro Robertson Ltd (Oil…

  4. Personalizing Science

    ERIC Educational Resources Information Center

    Danielowich, Robert M.

    2014-01-01

    Science teachers are aware of many social issues that intersect with science. These socio-scientific issues (SSIs) are "open-ended problems without clear-cut solutions [that] can be informed by scientific principles, theories, and data, but…cannot be fully determined by [them]" (Sadler 2011, p. 4). This article describes the SSI lessons…

  5. Deconstructing Science

    ERIC Educational Resources Information Center

    Trifonas, Peter Pericles

    2012-01-01

    In this paper I expand on the premises of Jesse Bazzul's thesis in his paper, "Neoliberal ideology, global capitalism, and science education: engaging the question of subjectivity," exploring the implications of the ideologies within the culturally emerging logic of science exposes the incommensurability of intents and purposes in its methods and…

  6. Soundsational Science

    ERIC Educational Resources Information Center

    Carrier, Sarah J.; Scott, Catherine Marie; Hall, Debra T.

    2012-01-01

    The science of sound helps students learn that sound is energy traveling in waves as vibrations transfer the energy through various media: solids, liquids, and gases. In addition to learning about the physical science of sound, students can learn about the sounds of different animal species: how sounds contribute to animals' survival, and how

  7. Life sciences

    SciTech Connect

    Day, L.

    1991-04-01

    This document is the 1989--1990 Annual Report for the Life Sciences Divisions of the University of California/Lawrence Berkeley Laboratory. Specific progress reports are included for the Cell and Molecular Biology Division, the Research Medicine and Radiation Biophysics Division (including the Advanced Light Source Life Sciences Center), and the Chemical Biodynamics Division. 450 refs., 46 figs. (MHB)

  8. Information Science.

    ERIC Educational Resources Information Center

    Saracevic, Tefko

    1999-01-01

    Presents personal analysis of information science as a field of scientific inquiry and professional practice that has evolved over the past half-century. Examines origin of information science in respect to problems of the information explosion, social role of field, nature of "information," structure of field in terms of problems addressed,…

  9. Legendary Science.

    ERIC Educational Resources Information Center

    O'Keefe, William A.; Joe, Jimson

    1998-01-01

    Spiders and insects are studied in both Navajo Studies and science classes at a middle school in New Mexico. In Navajo Studies, students learn the names of ground-dwelling insects and the connection between those names and traditional Navajo stories. In science class, students study arthropods to illustrate taxonomy of life, trophic and biological…

  10. Science Notes.

    ERIC Educational Resources Information Center

    Murray, A. J. S.; And Others

    1988-01-01

    Presents 31 science activities for use with high school or college science classes. Topics included are: chromatography, ecology, invertebrates, enzymes, genetics, botany, creep, crystals, diffusion, computer interfaces, acid rain, teaching techniques, chemical reactions, waves, electric fields, rainbows, electricity, magnetic fields, and a Pitot

  11. Integrated Science.

    ERIC Educational Resources Information Center

    Rainey, Larry; Miller, Roxanne Greitz

    1997-01-01

    Describes the Integrated Science program that integrates biology, earth/space science, chemistry, and physics over a three-year, spiraling sequence arranged around broad themes such as cycles, changes, patterns, and waves. Includes weekly telecasts via public television and satellite, teacher manuals, student handbooks, e-mail connections, staff…

  12. Teaching Science.

    ERIC Educational Resources Information Center

    Leyden, Michael B.

    1996-01-01

    Introduces a science activity where students were asked to purchase four different sizes of eggs; weigh the content of each; and determine whether small, medium, large, or extra large eggs are the best buy. Describes the data analysis process. Also introduces various science activities that make use of the egg shell. (MOK)

  13. Science Notes.

    ERIC Educational Resources Information Center

    Murray, A. J. S.; And Others

    1988-01-01

    Presents 31 science activities for use with high school or college science classes. Topics included are: chromatography, ecology, invertebrates, enzymes, genetics, botany, creep, crystals, diffusion, computer interfaces, acid rain, teaching techniques, chemical reactions, waves, electric fields, rainbows, electricity, magnetic fields, and a Pitot…

  14. Why Science?

    ERIC Educational Resources Information Center

    Primary Science Review, 2006

    2006-01-01

    This article presents people from many walks of life, including some well-known names, who share their views about science. Adam Hart-Davis, who studied chemistry at university and is now an author, photographer, historian and broadcaster, explains why science cannot start too soon. Lis Nairn, Manager, Stratigraphy, with Fugro Robertson Ltd (Oil

  15. Learning Science.

    ERIC Educational Resources Information Center

    Lapointe, Archie E.; And Others

    This publication reports the results of the second International Assessment of Educational Progress for science. Twenty countries assessed the mathematics and science achievement of 13-year-old students and 14 countries assessed 9-year-old students in these same subjects. In some cases, participants assessed virtually all age-eligible children in…

  16. [Basic science and applied science].

    PubMed

    Pérez-Tamayo, R

    2001-01-01

    A lecture was presented by the author at the Democratic Opinion Forum on Health Teaching and Research, organized by Mexico's National Health Institutes Coordinating Office, at National Cardiology Institute "Ignacio Chavez", where he presented a critical review of the conventional classification of basic and applied science, as well as his personal view on health science teaching and research. According to the author, "well-conducted science" is that "generating reality-checked knowledge" and "mis-conducted science" is that "unproductive or producing 'just lies' and 'non-fundable'. To support his views, the author reviews utilitarian and pejorative definitions of science, as well as those of committed and pure science, useful and useless science, and practical and esoterical science, as synonyms of applied and basic science. He also asserts that, in Mexico, "this classification has been used in the past to justify federal funding cutbacks to basic science, allegedly because it is not targeted at solving 'national problems' or because it was not relevant to priorities set in a given six-year political administration period". Regarding health education and research, the author asserts that the current academic programs are inefficient and ineffective; his proposal to tackle these problems is to carry out a solid scientific study, conducted by a multidisciplinary team of experts, "to design the scientific researcher curricula from recruitment of intelligent young people to retirement or death". Performance assessment of researchers would not be restricted to publication of papers, since "the quality of scientific work and contribution to the development of science is not reflected by the number of published papers". The English version of this paper is available at: http://www.insp.mx/salud/index.html PMID:11547597

  17. Science teaching in science education

    NASA Astrophysics Data System (ADS)

    Callahan, Brendan E.; Dopico, Eduardo

    2016-04-01

    Reading the interesting article Discerning selective traditions in science education by Per Sund, which is published in this issue of CSSE, allows us to open the discussion on procedures for teaching science today. Clearly there is overlap between the teaching of science and other areas of knowledge. However, we must constantly develop new methods to teach and differentiate between science education and teaching science in response to the changing needs of our students, and we must analyze what role teachers and teacher educators play in both. We must continually examine the methods and concepts involved in developing pedagogical content knowledge in science teachers. Otherwise, the possibility that these routines, based on subjective traditions, prevent emerging processes of educational innovation. Modern science is an enormous field of knowledge in its own right, which is made more expansive when examined within the context of its place in society. We propose the need to design educative interactions around situations that involve science and society. Science education must provide students with all four dimensions of the cognitive process: factual knowledge, conceptual knowledge, procedural knowledge, and metacognitive knowledge. We can observe in classrooms at all levels of education that students understand the concepts better when they have the opportunity to apply the scientific knowledge in a personally relevant way. When students find value in practical exercises and they are provided opportunities to reinterpret their experiences, greater learning gains are achieved. In this sense, a key aspect of educational innovation is the change in teaching methodology. We need new tools to respond to new problems. A shift in teacher education is needed to realize the rewards of situating science questions in a societal context and opening classroom doors to active methodologies in science education to promote meaningful learning through meaningful teaching.

  18. Introduction to the Science Teacher Training in an Information Society (STTIS) project

    NASA Astrophysics Data System (ADS)

    Pinto, Roser

    2002-03-01

    The cluster of papers in this Special Issue, contains some results from the Science Teacher Training in an Information Society (STTIS) project, which was funded by the European Commission. Five European universities were involved: Universite´ Denis Diderot-Paris 7 (France), Universita¤ 'Federico II da Napoli' (Italy), University of Oslo (Norway), Universitat Auto¤noma de Barcelona (Spain), and the University of Sussex (UK). The names of those involved are given in the Appendix. The following brief description of the aims and structure of the project sets the work reported here (in this cluster) in the context of the whole project. The project dealt with general questions and challenges that the Information Society poses to science educators.

  19. Determination des Parametres Atmospheriques des Etoiles Naines Blanches de Type DB

    NASA Astrophysics Data System (ADS)

    Beauchamp, Alain

    1995-01-01

    Les etoiles naines blanches dont les spectres visibles sont domines par des raies fortes d'helium neutre sont subdivisees en trois classes, DB (raies d'helium neutre seulement), DBA (raies d'helium neutre et d'hydrogene) et DBZ (raies d'helium neutre et d'elements lourds). Nous analysons trois echantillons de spectres observes de ces types de naines blanches. Les echantillons consistent, respectivement, de 48 spectres dans le domaine du visible (3700-5100 A). 24 dans l'ultraviolet (1200-3100 A) et quatre dans la partie rouge du visible (5100-6900) A). Parmi les objets de l'echantillon visible, nous identifions quatre nouvelles DBA, ainsi que deux nouvelles DBZ, auparavant classees DB. L'analyse nous permet de determiner spectroscopiquement les parametres atmospheriques, soit la temperature effective, la gravite de surface, ainsi que l'abondance relative de l'hydrogene, N(H)/N(He), dans le cas des DBA. Pour les objets plus chauds que ~15,000 K, la gravite de surface determinee est fiable, et nous obtenons les masses stellaires avec une relation masse -rayon theorique. Les exigences propres a l'analyse de ces objets ont requis d'importantes ameliorations dans la modelisation de leurs atmospheres et distributions de flux de radiation emis par ces derniers. Nous avons inclus dans les modeles d'atmospheres, pour la premiere fois a notre connaissance, les effets dus a la molecule He_sp{2 }{+}, ainsi que l'equation d'etat de Hummer et Mihalas (1988), qui tient compte des perturbations entre particules dans le calcul des populations des differents niveaux atomiques. Nous traitons la convection dans le cadre de la theorie de la longueur de melange. Trois grilles de modeles d'atmospheres a l'ETL (equilibre thermodynamique local) ont ete produites, pour un ensemble de temperatures effectives, gravites de surface et abondances d'hydrogene couvrant les proprietes des etoiles de nos echantillons; elles sont caracterisees par differentes parametrisations appelees, respectivement, ML1, ML2 et ML3, de la theorie de longueur de melange. Nous avons calcule une grille de spectres synthetiques avec les memes parametrisations que la grille de modeles d'atmospheres. Notre traitement de l'elargissement des raies de l'helium neutre a ete ameliore de facon significative par rapport aux etudes precedentes. D'une part, nous tenons compte de l'elargissement des raies produit par les interactions entre l'emetteur et les particules neutres (elargissements par resonance et de van der Waals) en plus de celui par les particules chargees (elargissement Stark). D'autre part, nous avons calcule nous-memes les profils Stark avec les meilleures theories d'elargissement disponibles pour la majorite des raies observees; ces profils depassent en qualite ce qui a ete publie jusqu'a ce jour. Nous avons calcule la distribution de masse des etoiles DB plus chaudes que 15,000 K. La distribution de masse des DB est tres etroite, avec environ les trois quarts des etoiles incluses dans l'intervalle 0.55-0.65 Modot. La masse moyenne des etoiles DB est de 0.58 M_⊙ avec sigma = 0.07. La difference principale entre les distributions de masse des DB et DA est la faible proportion de DB dans les ailes de la distribution, ce qui implique que les DA moins massives que ~0.4 M odot et plus massives que ~0.8 M_⊙ ne se convertissent pas en DB. Les objets les plus massifs de notre echantillon sont de type DBA, ce qui suggere que la masse elevee favorise la visibilite de l'hydrogene. (Abstract shortened by UMI.).

  20. Science Indicators and Science Priorities.

    ERIC Educational Resources Information Center

    Brooks, Harvey

    1982-01-01

    Discusses science/society interface and difficulties involved in developing realistic science indicators. Topics include: intrinsic vs. extrinsic indicators; four problems society faces as a result of technological activities (toxic chemicals, radioactive wastes, auto safety, cancer); research and development (R&D) priorities; international…

  1. Science Policy: Pangs of Science

    ERIC Educational Resources Information Center

    Handler, Philip

    1978-01-01

    Presented is the prepared text of a public lecture given by the president of the National Academy of Sciences. Dr. Handler attempts to articulate the state of science today. He deals with such issues as nuclear power and genetic engineering. (MDR)

  2. Science Instructors' Views of Science and Nature of Science

    ERIC Educational Resources Information Center

    Karakas, Mehmet

    2011-01-01

    This qualitative study examined how college science faculty who teach introductory level undergraduate science courses including the fields of chemistry, biology, physics, and earth science, understand and define science and nature of science (NOS). Participants were seventeen science instructors from five different institutions in the…

  3. Revolutionary Science.

    PubMed

    Casadevall, Arturo; Fang, Ferric C

    2016-01-01

    On rare occasions in the history of science, remarkable discoveries transform human society and forever alter mankind's view of the world. Examples of such discoveries include the heliocentric theory, Newtonian physics, the germ theory of disease, quantum theory, plate tectonics and the discovery that DNA carries genetic information. The science philosopher Thomas Kuhn famously described science as long periods of normality punctuated by times of crisis, when anomalous observations culminate in revolutionary changes that replace one paradigm with another. This essay examines several transformative discoveries in the light of Kuhn's formulation. We find that each scientific revolution is unique, with disparate origins that may include puzzle solving, serendipity, inspiration, or a convergence of disparate observations. The causes of revolutionary science are varied and lack an obvious common structure. Moreover, it can be difficult to draw a clear distinction between so-called normal and revolutionary science. Revolutionary discoveries often emerge from basic science and are critically dependent on nonrevolutionary research. Revolutionary discoveries may be conceptual or technological in nature, lead to the creation of new fields, and have a lasting impact on many fields in addition to the field from which they emerge. In contrast to political revolutions, scientific revolutions do not necessarily require the destruction of the previous order. For humanity to continue to benefit from revolutionary discoveries, a broad palette of scientific inquiry with a particular emphasis on basic science should be supported. PMID:26933052

  4. Revolutionary Science

    PubMed Central

    Fang, Ferric C.

    2016-01-01

    ABSTRACT On rare occasions in the history of science, remarkable discoveries transform human society and forever alter mankind’s view of the world. Examples of such discoveries include the heliocentric theory, Newtonian physics, the germ theory of disease, quantum theory, plate tectonics and the discovery that DNA carries genetic information. The science philosopher Thomas Kuhn famously described science as long periods of normality punctuated by times of crisis, when anomalous observations culminate in revolutionary changes that replace one paradigm with another. This essay examines several transformative discoveries in the light of Kuhn’s formulation. We find that each scientific revolution is unique, with disparate origins that may include puzzle solving, serendipity, inspiration, or a convergence of disparate observations. The causes of revolutionary science are varied and lack an obvious common structure. Moreover, it can be difficult to draw a clear distinction between so-called normal and revolutionary science. Revolutionary discoveries often emerge from basic science and are critically dependent on nonrevolutionary research. Revolutionary discoveries may be conceptual or technological in nature, lead to the creation of new fields, and have a lasting impact on many fields in addition to the field from which they emerge. In contrast to political revolutions, scientific revolutions do not necessarily require the destruction of the previous order. For humanity to continue to benefit from revolutionary discoveries, a broad palette of scientific inquiry with a particular emphasis on basic science should be supported. PMID:26933052

  5. Etude exploratoire des conceptions de la circulation sanguine aupres d'eleves de l'ordre collegial

    NASA Astrophysics Data System (ADS)

    Robitaille, Jean-Marc

    Il existe peu d'etudes sur les conceptions touchant les domaines de la biologie, notamment sur les conceptions de la circulation sanguine Nous avons observe egalement l'absence de recherche menee aupres d'eleves de l'ordre collegial sur cette question. Nous avons voulu combler une lacune en menant une recherche sur les conceptions de la circulation sanguine aupres d'eleves de l'ordre collegial. Pour mener cette recherche nous nous sommes inspires d'une methode developpee par Treagust (1988). Le premier niveau de formulation didactique etablit l'architecture du systeme et la fonction nutritive de la circulation. Le second niveau de formulation didactique decrit et relie les parametres de la dynamique de la circulation et leur relation: Pression, Debit et Resistance. Le troisieme niveau de formulation didactique s'interesse au controle de la circulation du sang dans un contexte d'homeostasie qui implique la regulation de la pression arterielle. Nous avons construit un questionnaire en nous guidant sur les niveaux de formulation didactique et l'analyse des entrevues menees aupres de dix-huit eleves, representatifs de la population cible. Ce questionnaire fut administre a un echantillon de 2300 eleves disperses dans six colleges de la region de Montreal. Notre echantillon comprend des eleves inscrits a des programmes de l'ordre collegial en Sciences de la nature et en Techniques de la sante et qui n'ont pas suivi le cours sur la circulation sanguine. Notre analyse des reponses des eleves de notre echantillon aux questions sur le premier niveau de formulation didactique revele que la majorite des eleves considerent que le systeme circulatoire relie les organes les uns aux autres dans un circuit en serie. Notre analyse revele egalement que la majorite des eleves estiment que les nutriments sont extraits du sang par les organes selon un processus de selection base sur les besoins determines par la fonction de l'organe. Ces besoins sont differents selon les organes qui ne prelevent que les nutriments necessaires. Au second niveau les reponses des eleves de la population indiquent une conception de la dynamique cardio-vasculaire axee d'abord sur le coeur, laissant aux vaisseaux un role passif de canaux. Ces reponses indiquent egalement que la dynamique circulatoire est reduite a une sequence d'etapes ponctuelles sans relation les unes avec les autres. Au troisieme niveau les reponses des eleves de la population font etat d'une conception du controle qui privilegie la satisfaction de besoins locaux, sans relation systemique. Nos resultats suggerent que les eleves de notre echantillon affichent une plus grande concordance avec l'expert pour les questions du premier niveau (70%) que pour les niveaux II (54%) et III (50%). Notre analyse des donnees revele que l'accord avec l'expert est eleve lorsque la questions touchent la description des structures et la definition de leurs roles et plus faible lorsque les questions touchent la dynamique et le controle. Il existerait donc un niveau de formulation qui correspond a la description de structures et un autre niveau qui recoupe toute la dynamique de la circulation et son controle. Du point de vue didactique lanalyse des donnees suggere que nous ne retrouvons pas une correspondance entre les niveaux de formulation didactique et les conceptions des eleves. (Abstract shortened by UMI.)

  6. PREFACE: Symmetries in Science XV

    NASA Astrophysics Data System (ADS)

    Schuch, Dieter; Ramek, Michael

    2012-08-01

    Logo Bregenz, the peaceful monastery of Mehrerau and the Opera on the Floating Stage again provided the setting for the international symposium 'Symmetries in Science'. The series which has been running for more than 30 years brings together leading theoreticians whose area of research is, in one way or another, related to symmetry. Since 1992 the meeting took place biannually in Brengez until 2003. In 2009, with the endorsement of the founder, Professor Bruno Gruber, we succeeded in re-establishing the series without external funding. The resounding success of that meeting encouraged us to continue in 2011 and, following on the enthusiasm and positive feedback of the participants, we expect to continue in 2013. Yet again, our meeting in 2011 was very international in flavour and brought together some 30 participants representing 12 nationalities, half of them from countries outside the European Union (from New Zealand to Mexico, Russia to Israel). The broad spectrum, a mixture of experienced experts and highly-motivated newcomers, the intensive exchange of ideas in a harmonious and relaxed atmosphere and the resulting joint projects are probably the secrets of why this meeting is considered to be so special to its participants. At the resumption in 2009 some leading experts and younger scientists from economically weak countries were unable to attend due to the lack of financial resources. This time, with the very worthy and unbureaucratic support of the 'Vereinigung von Freunden und Förderern der J W Goethe-Universität Frankfurt am Main' (in short: 'Friends and Supporters of the Frankfurt University'), it was possible for all candidates to participate. In particular some young, inspired scientists had the chance of presenting their work to a very competent, but also friendly, audience. We wish to thank the 'Freunde und Förderer' for supporting Symmetries in Science XV. Almost all participants contributed to the publication of this Conference Proceedings. There were also two colleagues who would have liked to participate but were unable to do so (M Horn and A Solomon); we agreed to incorporate their manuscripts into the Proceedings. We would like to thank the staff of Collegium Mehrerau for their hospitality. Once more special thanks to the Schenk Family for their continuing friendship and generous support. The informal evening meetings in these stimulating surroundings probably contributed as much to the scientific success as the lectures during the day and many personal contacts were made. Last, but not least, we would like to thank Yvette again for her unremitting support. Dieter Schuch and Michael Ramek Frankfurt am Main and Graz, July 2012 Conference photograph

  7. The source-sample stage of the new two-dimensional angular correlation of annihilation radiation spectrometer at Technische Universität München

    NASA Astrophysics Data System (ADS)

    Ceeh, Hubert; Weber, Josef Andreas; Leitner, Michael; Böni, Peter; Hugenschmidt, Christoph

    2013-04-01

    Angular correlation of annihilation radiation (ACAR) is a well established technique for the investigation of the electronic structure. A major limitation of ACAR studies is the available positron flux at a small spot on the sample. For this reason, the focus of this work is put on the discussion of a newly developed source-sample stage of the new 2D-ACAR spectrometer at Technische Universität München which uses an optimized static magnetic field configuration to guide the positrons onto the sample. The achieved spot diameter is dFWHM = 5.4 mm, with a high efficiency over the whole energy spectrum of the 22Na positron source. The implications of the performance of the source-sample stage are discussed with regard to 2D-ACAR measurements of single crystalline α-quartz, which serves as a model system for the determination of the total resolution. A value of (1.53 × 1.64) mrad2 FWHM was achieved at room temperature.

  8. La microscopie ionique analytique des tissus biologiques

    NASA Astrophysics Data System (ADS)

    Galle, P.

    Proposed in 1960 by R. Castaing and G. Slodzian, secondary ion emission microanalysis is a microanalytical method which is now largely used for the study of inert material. The instrument called the analytical ion microscope can also be used for the study of biological spécimens ; images representing the distribution of a given stable or radioactive isotope in a tissue section are obtained with a resolution of 0.5 μm. Among the characteristics of this method, two are of particular interest in biological research : its capacity for isotopic analysis and its very high sensitivity which makes possible for the first time a chemical analysis of element at a very low or even at a trace concentration in a microvolume. Proposé en 1960 par R. Castaing et G. Slodzian, la microanalyse par émission ionique secondaire est une méthode qui permet, entre autre, d'obtenir des images représentant la distribution des isotopes présents à la surface d'un échantillon solide avec une résolution de 0,5 μm. D'intérêt très général, cette méthode a été d'abord largement utilisée pour l'étude des matériaux inertes. Elle offre en outre des possibilités entièrement nouvelles dans le domaine de la recherche biomédicale. L'instrument réalisé, le microscope ionique analytique présente deux caractéristiques particulièrement intéressantes pour la biologie : la possibilité d'analyse isotopique, et l'extrême sensibilité permettant de détecter et de localiser dans une coupe histologique des éléments à des concentrations très faibles voire à l'état de trace.

  9. Les effets des interfaces sur les proprietes magnetiques et de transport des multicouches nickel/iron et cobalt/silver

    NASA Astrophysics Data System (ADS)

    Veres, Teodor

    Cette these est consacree a l'etude de l'evolution structurale des proprietes magnetiques et de transport des multicouches Ni/Fe et nanostructures a base de Co et de l'Ag. Dans une premiere partie, essentiellement bibliographique, nous introduisons quelques concepts de base relies aux proprietes magnetiques et de transport des multicouches metalliques. Ensuite, nous presentons une breve description des methodes d'analyse des resultats. La deuxieme partie est consacree a l'etude des proprietes magnetiques et de transport des multicouches ferromagnetiques/ferromagnetiques Ni/Fe. Nous montrerons qu'une interpretation coherente de ces proprietes necessite la prise en consideration des effets des interfaces. Nous nous attacherons a mettre en evidence, a evaluer et a etudier les effets de ces interfaces ainsi que leur evolution, et ce, suite a des traitements thermiques tel que le depot a temperature elevee et l'irradiation ionique. Les analyses correlees de la structure et de la magnetoresistance nous permettront d'emettre des conclusions sur l'influence des couches tampons entre l'interface et le substrat ainsi qu'entre les couches elles-memes sur le comportement magnetique des couches F/F. La troisieme partie est consacree aux systemes a Magneto-Resistance Geante (MRG) a base de Co et Ag. Nous allons etudier l'evolution de la microstructure suite a l'irradiation avec des ions Si+ ayant une energie de 1 MeV, ainsi que les effets de ces changements sur le comportement magnetique. Cette partie debutera par l'analyse des proprietes d'une multicouche hybride, intermediaire entre les multicouches et les materiaux granulaires. Nous analyserons a l'aide des mesures de diffraction, de relaxation superparamagnetique et de magnetoresistance, les evolutions structurales produites par l'irradiation ionique. Nous etablirons des modeles qui nous aideront a interpreter les resultats pour une serie des multicouches qui couvrent un large eventail de differents comportements magnetiques et ceci en fonction de l'epaisseur de la couche magnetique de Co. Nous verrons que dans ces systemes les effets de l'irradiation ionique sont fortement influences par l'energie de surface ainsi que par l'enthalpie de formation, largement positive pour le systeme Co/Ag.

  10. Forensic Science.

    ERIC Educational Resources Information Center

    Brettell, T. A.; Saferstein, R.

    1989-01-01

    Presents a review of articles appealing to forensic practitioners. Topics include: drugs and poisons, forensic biochemistry, and trace evidence. Lists noteworthy books published on forensic science topics since 1986. (MVL)

  11. Communicating Science

    USGS Publications Warehouse

    Farris, Gaye S.

    2005-01-01

    For science to have an impact, it must be communicated and easily accessible. The USGS National Wetlands Research Center communicates its research findings through several ways: publishing, the Web, the library, and education and outreach.

  12. Science Notes.

    ERIC Educational Resources Information Center

    Thurman, Shirley; And Others

    1988-01-01

    Describes 36 science activities. Topics include: osmosis, fermentation, anhydrobiotic organisms, breathing monitors, trypsin, weeds, amyloplasts, electrolysis, polarimeters, ethene ripening of fruit, colorimetry, diffusion, redox reactions, equilibria, acid-base relationships, electricity, power, resonance, measurement, parallax, amplifiers,…

  13. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1987

    1987-01-01

    Describes 20 teaching activities and experiments appropriate for use with various secondary school science classes. Instructional activities include the study of catalase, raising bees, a game about equilibrium, spectrometers, lead iodide, resonance, graphing, and electromagnetic waves. (TW)

  14. Overnight Science.

    ERIC Educational Resources Information Center

    Smith, Nancy N.; Stahl, Robert J.

    1981-01-01

    Outlines objectives for an elementary science camping program and summarizes general operational procedures. Campsite activities related to such topics as microorganisms, eye and sight, nature trails, bees, carpentry, and astronomy are described. (DS)

  15. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1990

    1990-01-01

    Included are 30 science activities that include computer monitoring, fieldwork, enzyme activity, pH, drugs, calorimeters, Raoult's Law, food content, solubility, electrochemistry, titration, physical properties of materials, gel filtration, energy, concepts in physics, and electricity. (KR)

  16. Scuba Science.

    ERIC Educational Resources Information Center

    Glickstein, Neil

    2000-01-01

    Introduces an integrated unit on scuba science. Studies oxygen in kinetic theory, Boyle's law, Charles's law, Dalton's law, human circulatory and respiratory systems, and diving dangers such as decompression sickness. (YDS)

  17. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1989

    1989-01-01

    Twenty-two activities are presented. Topics include: acid rain, microcomputers, fish farming, school-industry research projects, enzymes, equilibrium, assessment, science equipment, logic, Archimedes principle, electronics, optics, and statistics. (CW)

  18. Science Weekly.

    ERIC Educational Resources Information Center

    Science and Children, 1986

    1986-01-01

    Reviews the space classroom that would have been conducted by Christa McAuliffe during the space shuttle flight. Includes lab activities, word puzzles, vocabulary lists, and graph reading exercises for elementary science students. (ML)

  19. Forensic Science

    ERIC Educational Resources Information Center

    Cobb, P. G. W.

    1973-01-01

    Summarizes the type of work carried out by forensic chemists and the minimum qualification needed for appointment. Indicates that there are eight Home Office regional forensic science laboratories in addition to the Central Research Establishment at Aldermaston. (CC)

  20. Science Scenarios.

    ERIC Educational Resources Information Center

    Cronin-Jones, Linda

    2000-01-01

    Focuses on using science-related issues in classrooms. Explains how to select these issues and create a scenario, and presents a sample scenario for a role-playing activity. Provides several format structures for role-plays. (YDS)

  1. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1990

    1990-01-01

    Presented are 25 science activities on colorations of prey, evolution, blood, physiology, nutrition, enzyme kinetics, leaf pigments, analytical chemistry, milk, proteins, fermentation, surface effects of liquids, magnetism, drug synthesis, solvents, wintergreen synthesis, chemical reactions, multicore cables, diffraction, air resistance,

  2. Dismal Science

    PubMed Central

    Evans, Robert G.

    2009-01-01

    “No prediction, no science.” By this standard, the past year has not been kind to the pretensions of “economic science,” Nobel prizes notwithstanding. The issue is more than semantic. As Neil Postman (1992) pointed out, sciences study natural processes that repeat themselves under constant conditions. The social disciplines study practices of human communities that are embedded in history. There are no constant conditions; it is impossible to step into the same river twice (Heraclitus). “Physics envy” has led mainstream economic theorists to attempt to understand their discipline through methods and models borrowed from the natural sciences. (By unfortunate coincidence, these have reinforced a certain class of ideological preconceptions and associated economic interests.) Today the results of this methodological mismatch speak for themselves. PMID:20436803

  3. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1985

    1985-01-01

    Presents 23 experiments, activities, field projects and computer programs in the biological and physical sciences. Instructional procedures, experimental designs, materials, and background information are suggested. Topics include fluid mechanics, electricity, crystals, arthropods, limpets, acid neutralization, and software evaluation. (ML)

  4. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1987

    1987-01-01

    This section of the journal includes several short notes on science activities and materials for secondary schools. Activities and materials are included that relate to biology, microbiology, microcomputers, chemistry, and physics. (RH)

  5. Science Notes.

    ERIC Educational Resources Information Center

    Thurman, Shirley; And Others

    1988-01-01

    Describes 36 science activities. Topics include: osmosis, fermentation, anhydrobiotic organisms, breathing monitors, trypsin, weeds, amyloplasts, electrolysis, polarimeters, ethene ripening of fruit, colorimetry, diffusion, redox reactions, equilibria, acid-base relationships, electricity, power, resonance, measurement, parallax, amplifiers,

  6. Elaboration de nouvelles approches micromecaniques pour l'optimisation des performances mecaniques des materiaux heterogenes

    NASA Astrophysics Data System (ADS)

    Aboutajeddine, Ahmed

    Les modeles micromecaniques de transition d'echelles qui permettent de determiner les proprietes effectives des materiaux heterogenes a partir de la microstructure sont consideres dans ce travail. L'objectif est la prise en compte de la presence d'une interphase entre la matrice et le renforcement dans les modeles micromecaniques classiques, de meme que la reconsideration des approximations de base de ces modeles, afin de traiter les materiaux multiphasiques. Un nouveau modele micromecanique est alors propose pour tenir compte de la presence d'une interphase elastique mince lors de la determination des proprietes effectives. Ce modele a ete construit grace a l'apport de l'equation integrale, des operateurs interfaciaux de Hill et de la methode de Mori-Tanaka. Les expressions obtenues pour les modules globaux et les champs dans l'enrobage sont de nature analytique. L'approximation de base de ce modele est amelioree par la suite dans un nouveau modele qui s'interesse aux inclusions enrobees avec un enrobage mince ou epais. La resolution utilisee s'appuie sur une double homogeneisation realisee au niveau de l'inclusion enrobee et du materiau. Cette nouvelle demarche, permettra d'apprehender completement les implications des approximations de la modelisation. Les resultats obtenus sont exploites par la suite dans la solution de l'assemblage de Hashin. Ainsi, plusieurs modeles micromecaniques classiques d'origines differentes se voient unifier et rattacher, dans ce travail, a la representation geometrique de Hashin. En plus de pouvoir apprecier completement la pertinence de l'approximation de chaque modele dans cette vision unique, l'extension correcte de ces modeles aux materiaux multiphasiques est rendue possible. Plusieurs modeles analytiques et explicites sont alors proposee suivant des solutions de differents ordres de l'assemblage de Hashin. L'un des modeles explicite apparait comme une correction directe du modele de Mori-Tanaka, dans les cas ou celui ci echoue a donner de bons resultats. Finalement, ce modele de Mori-Tanaka corrige est utilise avec les operateurs de Hill pour construire un modele de transition d'echelle pour les materiaux ayant une interphase elastoplastique. La loi de comportement effective trouvee est de nature incrementale et elle est conjuguee a la relation de la plasticite de l'interphase. Des simulations d'essais mecaniques pour plusieurs proprietes de l'interphase plastique a permis de dresser des profils de l'enrobage octroyant un meilleur comportement au materiau.

  7. Community Environmental Response Facilitation Act (CERFA) report. Fort Des Moines, Des Moines, Iowa. Final report

    SciTech Connect

    Young, B.; Rausch, K.; Kang, J.

    1994-04-01

    This report presents the results of the Community Environmental Response Facilitation Act (CERFA) investigation conducted by The Earth Technology Corporation (TETC) at the Fort Des Moines, a U.S. Government property selected for closure by the Base Realignment and Closure (BRAC) Commission. Under CERFA Federal agencies are required to identify real property that can be immediately reused and redeveloped. Satisfying this objective requires the identification of real property where no hazardous substances or petroleum products, regulated by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), were stored for one year or more, known to have been released, or disposed. Fort Des Moines is a 53.28-acre site located in Polk County, Iowa, within the city limits of Des Moines. The installation's primary mission is to provide support and shelter for the U.S. Army Reserve. Activities associated with the property that have environmental significance are photographic processing, vehicle maintenance, printing, and fuel storage. TETC reviewed existing investigation documents; U.S. Environmental Protection Agency (USEPA), State, and county regulatory records; environmental data bases; and title documents pertaining to Fort Des Moines during this investigation. In addition, TETC conducted interviews and visual inspections of Fort Des Moines as well as visual inspections and data base searches for the surrounding properties. Information in this CERFA Report was current as of April 1994.

  8. TRANSPLANTATION EN MASSE DES ORGANES ABDOMINAUX

    PubMed Central

    STARZL, T.

    2010-01-01

    Les transplantations multi-organes, comprenant les blocs foie-duodénum-pancréas, foie-estomac-duodénum-pancréas, et foie-intestin sont réalisées avec un succés croissant Ces techniques et leurs combinaisons variées de transplantation monobloc ne sont pas de pratique courante. Les techniques de prélévement, de conservation et de soins post-opératoires sont décrites pour la transplantation multi-organes compléte ainsi que pour les variantes incomplétes. Le probléme particulier à ce type de transplantation est celui de la transplantation intestinale, c’est-à-dire la transplantation d’un organe à composante lymphoréticulaire complexe ce qui peut provoquer un syndrome greffon contre hôte. Par erreur de conception, et un peu par esprit de systéme, les efforts par le passé étaient dirigés sur la modification et la destruction des systémes lymphoréticulaires grâce au traitement préalable du donneur ou des organes transplantés, par médicaments, radiation ou autres moyens. Actuellement, I’idée directrice est de garder intacte les systémes lymphoréticulaires qui deviennent alors le site d’une circulation à double sens aprés transplantation. Avec la puissante immunodépression que fournit le FK 506, les cellules lymphoréticulaires du donneur peuvent circuler chez le receveur sans créer de syndrome du greffon contre hôte clinique et les cellules de la greffe s’assimilent à celles du receveur (chimérisme local) sans provoquer de rejet. Même si I’on évite le rejet ou le syndrome greffon contre hôte, il existe, à côté de ces entités, des relations métaboliques entre les organes greffés ainsi qu’entre les organes greffés et les viscéres du receveur laissés en place, qui peuvent influencer I’avenir soit des organes greffés, soit des organes laissés en place. Parmi les échanges métaboliques les mieux connus actuellement, il y a les facteurs splanchniques hépatotrophes endogénes, dont I’insuline est la mieux étudiée. Une meilleure compréhension de ces facteurs, d’origine immunologique ou non immunologique, combinés avec la puissante immunodépression dont nous disposons à présent, doit être une stimulation à la transplantation des organes abdominaux et en particulier, des viscéres creux qui, jusqu’à présent, ont fait obstacle aux efforts des chirurgiens et cliniciens s’intéressant à la transplantation d’organes. PMID:1742622

  9. Étude des déplacements induits par des précipités dans des alliages à base de cuivre

    NASA Astrophysics Data System (ADS)

    Guillon, I.; Servant, C.; Lyon, O.

    2004-11-01

    Cette étude a pour but de mieux comprendre les premières étapes des phénomènes se produisant lors de la formation de nanoprécipités. En effet, la microstructure des alliages conditionne leurs propriétés mécaniques, et donc l'emploi de ces matériaux. Alors que l'anisotropie des déformations élastiques permet d'expliquer la morphologie des précipités formés lors des traitements thermiques de revenu, peu d'études se sont attachées à les déterminer expérimentalement. Mots clés : transformations de phases, diffusion/diffraction, synchrotron, alliages à base Cu, déplacements

  10. Early Results from the DES SN Survey

    NASA Astrophysics Data System (ADS)

    Scolnic, Daniel; Dark Energy Survey

    2016-01-01

    The Dark Energy Survey Supernova program (DES SN) has already discovered over 1000 Type Ia supernovae with well-sampled multi-color light curves in the redshift range 0.1 < z < 1.2. I will present an overview of the survey and show recent advances in our detection, photometry, calibration and spectroscopic follow-up pipelines. I will go over initial results from photometric classification of our sample and discuss methods used to reach measurements of cosmological parameters.

  11. Communique: Special Issue on the International Network for Cooperation in Northern Science Created at a Meeting held in Edmonton, Alberta (October 12-15, 1982). Summary of Discussions and Agreements Reached = Numero special sur le Reseau Scientifique Internationale pour le Nord cree a la reunion tenue a Edmonton, Alberta (du 12 au 15 octobre 1982). Resume des discussions et accords conclus.

    ERIC Educational Resources Information Center

    Communique, 1983

    1983-01-01

    Delegations from Canada, Finland, Greenland, Norway, Sweden, and the United States agreed to the establishment of a network for cooperation among individuals engaged in problems peculiar to the circumpolar North. The Northern Science Network, established within the Unesco Man and the Biosphere Program, consists of three themes: studies on the…

  12. Newtons Universum. Materialien zur Geschichte des Kraftbegriffes.

    NASA Astrophysics Data System (ADS)

    Mit einem Vorwort von E. Seibold und einer Einführung von W. Neuser. This book is a selection of 15 articles published in the journal "Spektrum der Wissenschaft". The original English versions of the papers were first published in "Scientific American". Contents: 1. Impetustheorie und Intuition in der Physik (M. McCloskey). 2. Mittelalterliche Ursprünge der industriellen Revolution (T. S. Reynolds). 3. Leonardo da Vincis Beiträge zur theoretischen Mechanik (V. Foley, W. Soedel). 4. Nikolaus Kopernikus und Tycho Brahe (O. Gingerich). 5. Keplers Entdeckung der ersten beiden Planetengesetze (C. Wilson). 6. Galileis Entdeckung des Fallgesetzes (S. Drake). 7. Galileis Beobachtung des Neptun (S. Drake, C. T. Kowal). 8. Galileo Galilei und der Schatten des Giordano Bruno (L. S. Lerner, E. A. Gosselin). 9. Der Fall Galilei (O. Gingerich). 10. Newtons Apfel und Galileis "Dialog" (S. Drake). 11. Newtons Gravitationsgesetz - aus Formeln wird eine Idee (I. B. Cohen). 12. Christopher Wren: Astronom und Architekt (H. Dorn, R. Mark). 13. Atomismus und Kräfte in der Geschichte (L. Holliday). 14. Ein Elitezirkel vor 200 Jahren: Die Lunar Society von Birmingham (L. Ritchie-Calder). 15. Sadi Carnot: Technik und Theorie der Dampfmaschine (S. S. Wilson).

  13. Der Beta-Zerfall der Atomkerne und das Alter des Universums.

    NASA Astrophysics Data System (ADS)

    Klapdor, H. V.

    Contents: 1. Einleitung: Schwache Wechselwirkung und Entwicklung des Universums. 2. Ein Durchbruch im Verständnis des β-Zerfalls neutronenreicher Kerne. 3. Elementsynthese und das Alter des Universums. 4. Kosmologie.

  14. Sciences and society

    ScienceCinema

    None

    2011-04-25

    J.Luns des Pays-Bas, ancien sécétaire général de NATO (OTAN=Organisation du traité de l'Atlantique Nord) parle du passé, présent et future de la défense européenne et des relations est et ouest

  15. Sécurité au-delà des mythes et des croyances

    ScienceCinema

    None

    2011-10-06

    Présentation orale en français, support visuel en français et en anglais. La pire des failles de sécurité est l'impression de sécurité. Le décalage entre la compréhension que l?on a des technologies utilisées, et leurs potentiels réels, ainsi que l'impact potentiellement négatif qu'elles peuvent avoir sur nos vies, n'est pas toujours compris, ou pris en compte par la plupart d'entre-nous. On se contente de nos perceptions pour ne pas avoir à se confronter à la réalité... Alors qu'en est-il vraiment ? En matière de sécurité qui de l'humain ou des technologies a le contrôle ?

  16. Science Fairs for Science Literacy

    NASA Astrophysics Data System (ADS)

    Mackey, Katherine; Culbertson, Timothy

    2014-03-01

    Scientific discovery, technological revolutions, and complex global challenges are commonplace in the modern era. People are bombarded with news about climate change, pandemics, and genetically modified organisms, and scientific literacy has never been more important than in the present day. Yet only 29% of American adults have sufficient understanding to be able to read science stories reported in the popular press [Miller, 2010], and American students consistently rank below other nations in math and science [National Center for Education Statistics, 2012].

  17. Inhomogeneites dans le Vent des Etoiles Wolf-Rayet

    NASA Astrophysics Data System (ADS)

    Robert, Carmelle

    1992-01-01

    Des mesures spectroscopiques effectuees avec un haut rapport signal sur bruit et une bonne resolution ont demontre l'existence de regions perturbees en mouvement dans le vent d'etoiles Wolf-Rayet (WR). L'echantillon d'objets etudies ici comprend 9 etoiles WR couvrant differents sous-types WN et WC. De nombreuses petites structures variables superposees au profil des raies d'emission formees dans le vent stellaire signalent la presence des perturbations. L'etude des variations globales des raies et l'examen des micro-structures individuelles ont permis de decrire plusieurs caracteristiques des perturbations. Entre autres, on observe des correlations significatives entre le niveau de variabilite des raies et certains parametres des etoiles qui confirment que le phenomene de variabilite est intrinseque au vent stellaire. En comparant les changements des vitesses radiales et des largeurs equivalentes des differentes raies d'une meme etoile, on conclut que les regions perturbees ont une etendue finie par rapport a l'enveloppe des etoiles. On peut facilement suivre les structures individuelles sur une periode de temps couvrant ~eq8 heures (et peut etre meme 24 heures) avant qu'elles ne disparaissent. Durant ce temps les structures se deplacent en s'eloignant du centre de la raie. A partir des differents comportements notes lors de l'analyse des variations globales et lors de l'examen des structures individuelles, on propose de representer les perturbations par un modele d'inhomogeneites discretes en expansion dans le vent. On suppose simplement que les inhomogeneites emettent comme le vent global (et absorbent aussi si le vent global montre un profil P Cyg). La superposition du graphique de l'acceleration radiale moyenne des inhomogeneites de WR140 en fonction de leur vitesse radiale et du modele theorique d'inhomogeneites qui suivent la loi generale de vitesse donne un taux d'acceleration lent, avec beta >= 3 pour les inhomogeneites de cette etoile. On obtient, entre autres, une correlation entre le nombre d'inhomogeneites detectees et la vitesse terminale. Cette relation explique bien l'anti-correlation observee entre le niveau de variabilite spectroscopique, photometrique ou polarimetrique et la vitesse terminale. On estime pour toutes les etoiles une masse moyenne des inhomogeneites de 7 times 10^{ -10} Modot et un taux de perte de masse sous la forme d'inhomogeneites detectables qui correspond a 10% de la perte de masse du vent total. L'histogramme du nombre d'inhomogeneites en fonction du leur flux pourrait cependant predire l'existence d'un grand nombre de petites structures non-detectees ici a cause du rapport signal sur bruit relativement trop faible. Ce resultat interessant, qui demande cependant a etre verifie, suggere que le vent pourrait etre forme d'un ensemble quasi infini d'inhomogeneites. En ajustant une loi de puissance dans l'histogramme du flux de chaque etoile, on calcule, pour les plus grosses structures, un exposant = -2.4 +/- 0.2. On constate alors que cette valeur est compatible avec celle que predit la turbulence supersonique. Les structures observees dans les spectres des etoiles WR ont des caracteristiques tres semblables a celles des etoiles O. On propose alors que les perturbations observees chez ces 2 types d'etoiles ont une meme origine. Parmi les mecanismes deja proposes dans le passe pour expliquer les variations des etoiles O et WR (instabilites radiatives, pulsations et champ magnetique) on ne saurait encore dire <=uel, ou lesquels, correspondent le mieux aux observations. Dans les projets futurs, on propose de considerer aussi le role que pourrait avoir la turbulence pour expliquer les perturbations du vent stellaire.

  18. The Opportunity To Eradicate Peste des Petits Ruminants.

    PubMed

    Mariner, Jeffrey C; Jones, Bryony A; Rich, Karl M; Thevasagayam, Samuel; Anderson, John; Jeggo, Martyn; Cai, Yi; Peters, Andrew R; Roeder, Peter L

    2016-05-01

    Peste des petits ruminants (PPR) is a highly infectious disease of sheep and goats that is caused by PPR virus, a member of the genus Morbillivirus that includes the viruses that cause rinderpest (RP) in cattle. RP was the first animal disease to be globally eradicated in 2011 and is only the second disease, after smallpox, to have ever been eradicated. PPR is one of the principal constraints to small ruminant production in Africa, Asia, and the Middle East. The epidemiology of PPR and RP as well as the technologies available for their diagnosis and control are similar. The conditions that favored the eradication of RP are also largely present for PPR. In this work, we outline the evolving strategy for eradication in light of current opportunities and challenges, as well as the lessons from other eradication programs in animal and human health. The global PPR situation and technology for its control are summarized. A strategy based on the lessons from previous eradication efforts that integrate epidemiology, social science, and economics as tools to target and motivate vaccination is summarized. Major aspects of the cost and benefit-cost analysis of the indicated program are presented. The overall undiscounted cost of eradication was estimated as $3.1 billion, and the benefit-cost ratio for the most likely scenario was estimated at 33.8. We close with a discussion of the possible next steps. PMID:27183645

  19. Paternité des articles et intérêts concurrents : une analyse des recommandations aux auteurs des journaux traitant de pratique pharmaceutique

    PubMed Central

    Courbon, Ève; Tanguay, Cynthia; Lebel, Denis; Bussières, Jean-François

    2014-01-01

    RÉSUMÉ Contexte : La présence d’auteurs honorifiques et fantômes ainsi que les intérêts concurrents représentent des difficultés bien documentées, liées à la publication d’articles scientifiques. Il existe des lignes directrices encadrant la rédaction et la publication de manuscrits scientifiques, notamment celles de l’International Committee of Medical Journal Editors (ICMJE). Objectifs : L’objectif principal de cette étude descriptive et transversale visait à recenser les instructions portant sur la paternité des articles et les intérêts concurrents provenant des recommandations aux auteurs des journaux traitant de pratique pharmaceutique. L’objectif secondaire visait à déterminer des mesures correctrices pour une paternité des articles plus transparente. Méthode : La recherche a débuté par l’identification des journaux traitant de pratique pharmaceutique. La consultation des instructions aux auteurs des journaux a permis ensuite de recenser les recommandations destinées à éviter les problèmes de paternité des articles et d’intérêts concurrents. Finalement, les membres de l’équipe de recherche se sont consultés afin de définir des mesures correctrices possibles à l’intention des chercheurs. Résultats : Des 232 journaux traitant de pharmacie, 33 ont été définis comme traitant de pratique pharmaceutique. Un total de 24 (73 %) journaux mentionnaient suivre la politique de l’ICMJE, 14 (42 %) demandaient aux auteurs de remplir un formulaire de déclaration d’intérêts concurrents au moment de la soumission de l’article, 17 (52 %) présentaient une définition de la qualité d’auteur et 5 (15 %) demandaient de détailler les contributions de chaque auteur. Une grille de 40 critères a été élaborée pour définir l’attribution du statut d’auteur. Conclusion : Moins de la moitié des journaux demandait aux auteurs de transmettre un formulaire de déclaration des intérêts concurrents au moment de la soumission d’un article et seulement la moitié des journaux avait donné une définition de la qualité d’auteur. La publication scientifique de travaux sur les pratiques pharmaceutiques n’est pas à l’abri des manques de transparence liés à la publication. L’utilisation d’une grille décrivant la contribution de chaque auteur et la publication en ligne des travaux peuvent contribuer à limiter ces risques. PMID:24970938

  20. Traitement des fractures des plateaux externes par vissage percutané assisté par arthroscopie

    PubMed Central

    Abouchane, Merouane; Belmoubarik, Amine; Benameur, Hamza; Haddoun, Ahmed Reda; Nechad, Mohammed

    2015-01-01

    Le but de notre étude est d'évaluer les résultats de fractures des plateaux tibiaux externes traitées par ostéosynthèse percutanée assistée par arthroscopie. Dix patients (8 hommes et 2 femmes) de 32 ans en moyenne ont subi cette intervention afin de réparer des fractures des plateaux tibiaux Schatzker I-III. Après avoir appliqué un garrot pneumatique, nous avons réduit et fixé la fracture au moyen de vis cannelées souschondrales. Lésions associées retrouvent deux lésions partielles du ménisque externe ont été retrouvé, traitées par résection partielle. Une orthèse de genou été de mise à but antalgique et protectrice pendant six semaines avec béquillage et interdiction de l'appui pour une durée de douze semaines avec reprise d'appui partiel au delà. La durée d'hospitalisation été d'une moyenne de cinq jours. La rééducation passive a été commence le lendemain de l'intervention et continuait dans chez un kinésithérapeute à la sortie du patient du service. Le suivi été à J7, J15, 1mois, 3mois, 6 mois puis tous les 6 mois. Neuf de nos patients ont été revu régulièrement sauf un perdu de vue. Le recul moyen de notre série été de 16 mois (10 et 24 mois). Le score de Lysholm a été utilisé pour évaluer les résultats cliniques chez nos neuf patients: excellent chez trois patients bons chez trois moyen chez un seul et mauvais chez deux patients. Tous nos neuf patients ont consolidé (figure 10 contrôle scopique d un article). Aucune gonarthrose n'a été note chez nos neuf patients due essentiellement au recul moyen faible de 16 mois. Le traitement des fractures des plateaux tibiaux externes assisté par arthroscopie produit des résultats satisfaisants et peut être accepté comme solution de rechange efficace au traitement des fractures des plateaux tibiaux causées par un choc de faible énergie. PMID:26587137

  1. Etude des phenomenes dynamiques ultrarapides et des caracteristiques impulsionnelles d'emission terahertz du supraconducteur YBCO

    NASA Astrophysics Data System (ADS)

    Savard, Stephane

    Les premieres etudes d'antennes a base de supraconducteurs a haute temperature critique emettant une impulsion electromagnetique dont le contenu en frequence se situe dans le domaine terahertz remontent a 1996. Une antenne supraconductrice est formee d'un micro-pont d'une couche mince supraconductrice sur lequel un courant continu est applique. Un faisceau laser dans le visible est focalise sur le micro-pont et place le supraconducteur dans un etat hors-equilibre ou des paires sont brisees. Grace a la relaxation des quasiparticules en surplus et eventuellement de la reformation des paires supraconductrices, nous pouvons etudier la nature de la supraconductivite. L'analyse de la cinetique temporelle du champ electromagnetique emis par une telle antenne terahertz supraconductrice s'est averee utile pour decrire qualitativement les caracteristiques de celle-ci en fonction des parametres d'operation tels que le courant applique, la temperature et la puissance d'excitation. La comprehension de l'etat hors-equilibre est la cle pour comprendre le fonctionnement des antennes terahertz supraconductrices a haute temperature critique. Dans le but de comprendre ultimement cet etat hors-equilibre, nous avions besoin d'une methode et d'un modele pour extraire de facon plus systematique les proprietes intrinseques du materiau qui compose l'antenne terahertz a partir des caracteristiques d'emission de celle-ci. Nous avons developpe une procedure pour calibrer le spectrometre dans le domaine temporel en utilisant des antennes terahertz de GaAs bombarde aux protons H+ comme emetteur et detecteur. Une fois le montage calibre, nous y avons insere une antenne emettrice dipolaire de YBa 2Cu3O7-delta . Un modele avec des fonctions exponentielles de montee et de descente du signal est utilise pour lisser le spectre du champ electromagnetique de l'antenne de YBa 2Cu3O7-delta, ce qui nous permet d'extraire les proprietes intrinseques de ce dernier. Pour confirmer la validite du modele choisi, nous avons mesure les proprietes intrinseques du meme echantillon de YBa2Cu3O7- delta avec la technique pompe-visible et sonde-terahertz donnant, elle aussi, acces aux temps caracteristiques regissant l'evolution hors-equilibre de ce materiau. Dans le meilleur scenario, ces temps caracteristiques devraient correspondre a ceux evalues grace a la modelisation des antennes. Un bon controle des parametres de croissance des couches minces supraconductrices et de fabrication du dispositif nous a permis de realiser des antennes d'emission terahertz possedant d'excellentes caracteristiques en terme de largeur de bande d'emission (typiquement 3 THz) exploitables pour des applications de spectroscopie resolue dans le domaine temporel. Le modele developpe et retenu pour le lissage du spectre terahertz decrit bien les caracteristiques de l'antenne supraconductrice pour tous les parametres d'operation. Toutefois, le lien avec la technique pompe-sonde lors de la comparaison des proprietes intrinseques n'est pas direct malgre que les deux techniques montrent que le temps de relaxation des porteurs augmente pres de la temperature critique. Les donnees en pompe-sonde indiquent que la mesure du temps de relaxation depend de la frequence de la sonde, ce qui complique la correspondance des proprietes intrinseques entre les deux techniques. De meme, le temps de relaxation extrait a partir du spectre de l'antenne terahertz augmente en s'approchant de la temperature critique (T c) de YBa2Cu 3O7-delta. Le comportement en temperature du temps de relaxation correspond a une loi de puissance qui est fonction de l'inverse du gap supraconducteur avec un exposant 5 soit 1/Delta 5(T). Le travail presente dans cette these permet de mieux decrire les caracteristiques des antennes supraconductrices a haute temperature critique et de les relier aux proprietes intrinseques du materiau qui les compose. De plus, cette these presente les parametres a ajuster comme le courant applique, la puissance de la pompe, la temperature d'operation, etc, afin d'optimiser l'emission et les performances de ces antennes supraconductrices entre autres pour maximiser leur etendue en frequence dans une perspective d'application en spectroscopie terahertz. Cependant, plusieurs des resultats obtenus soulevent la difficulte de decrire l'etat hors-equilibre et la necessite de developper une theorie pour le supraconducteur YBa2 Cu3O7-delta

  2. Le changement comme tradition dans la recherche et la formation a la recherche en biotechnologie et en peripherie Etude de cas en sciences de la sante, sciences naturelles et genie

    NASA Astrophysics Data System (ADS)

    Bourque, Claude Julie

    Le champ de la recherche scientifique et de la formation a la recherche est traverse depuis quelques dizaines d'annees par plusieurs courants et discours associes au changement, mais peu de travaux empiriques permettent de comprendre ce qui change concretement. C'est la contribution originale de cette these au champ de l'education, plus specifiquement a l'etude sociologique de l'enseignement superieur ou sont concentrees les activites liees a la triade thematique du programme doctoral dans lequel elle a ete produite : recherche, formation et pratique. L'enquete-terrain a ete realisee en 2009 et 2010 aupres de 808 repondants affilies a 60 etablissements au Quebec et a produit un vaste materiau de nature mixte (donnees quantitatives et qualitatives). Un portrait de la nebuleuse biotechnologique qui touche les secteurs des sciences de la sante, des sciences naturelles et du genie a ete realise. Ce domaine concerne des dizaines de disciplines et se revele de nature transdisciplinaire, mais les pratiques n'y sont pas davantage marquees par le changement que celles d'autres domaines connexes. Les dynamiques sociales ont fait l'objet d'analyses comparatives dans quatre contextes: le choix des programmes, des objets et des methodes, le financement, la diffusion et la planification de la carriere. Les resultats indiquent que les echanges entre les agents traditionnellement situes au coeur des activites de recherche dominent ces dynamiques dans tous les contextes etudies. L'etude des representations au fondement des pratiques a revele l'existence de trois ecoles de pensee qui coexistent dans le champ scientifique: academique, pragmatique et economiste. Ces ecoles permettent de categoriser les agents en fonction des zones de fractures qui marquent leurs oppositions tout en identifiant ce qu'ils ont en commun. Les representations et les pratiques liees a la formation temoignent d'un habitus plutot homogene, alors que les contradictions semblent plus souvent ancrees dans des luttes universitaires que scientifiques, concentrees sur la negociation du capital scientifique, symbolique et economique en jeu dans la formation doctorale, dans les carrieres auxquelles elle mene, et dans les qualites du titre de Ph.D. Au final, la confusion entre des logiques opposees peut etre reduite en reinterpretant le changement comme tradition du champ scientifique. Mots-cles Sociologie, education, enseignement superieur, science et technologie, biotechnologie, formation doctorale, champ scientifique, reseaux sociaux

  3. Science exchanges

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    Dwindling scientific and technical exchange between the United States and the Soviet Union and prospects for enhancing such exchanges were discussed at an August 2 hearing by the Foreign Affairs Committee of the U.S. House of Representatives. The committee also heard overviews on the United States' approach to international exchange of science and technology. The hearing was the first in a series on current and future international science and technology programs.Four of eight science and technology agreements with the USSR that have expired in the last 15 months, including one on space, have not been renewed. The remaining four agreements have been extended into 1987 and 1988. Two others, including one on oceanography, are scheduled to run out in 1984.

  4. Literacy, science, and science education

    NASA Astrophysics Data System (ADS)

    McVittie, Janet Elizabeth

    In examining the connections between literacy, science and science education, I laid out a number of questions. For example, what sorts of literate tools might facilitate writing to learn, and do children who are just becoming literate use these tools? I then examined the writing of children in science class in an attempt to determine if their writing can indeed facilitate their learning. The results of this research could help teachers make decisions about the use of writing in the learning of science. The kinds of literate tools I identified as being potentially helpful were transitionals---those words or grammatical devices which demonstrate how ideas are connected. Also, I suggested that data tables, sentences and paragraphs were also useful for students to learn. I found that grade 5/6 students used a wide range of literate tools, but that they were much more competent with those tools which were both oral and literate than those which could only be used for writing (punctuation, sentences, paragraphs, and data tables). When I attempted to determine if the children used their writing to learn, I found very little evidence that this was certainly so. However, there was some evidence that paragraphs had the potential to create a "dialogue" between student writing and thinking, so the students could make more explicit connections between science ideas. Lastly, I noticed certain gender difference in the classroom. Because of this, I contrasted the writing of the girls with the writing of the boys. I learned the girls were generally much more capable writers than the boys. More interesting, however, was that the girls generally attempted to explain their science concepts in different ways than did the boys. The girls were more likely to rely on their own reasoning, whereas the boys were more likely to persist in using culturally created science explanations. The research findings have important implications for analyzing students' learning and for finding ways to facilitate learning for both girls and boys.

  5. Chemical Effects in 11-Year Solar Cycle Simulations With the Freie Universität Berlin Climate Middle Atmosphere Model With Interactive Chemistry (FUB-CMAM-CHEM)

    NASA Astrophysics Data System (ADS)

    Langematz, U.; Grenfell, J. L.; Matthes, K.

    2004-12-01

    Parameterisation of NOx transport from the mesosphere to the stratosphere may be important when simulating the 11-year solar cycle influence upon stratospheric ozone in climate- chemistry models (CCMs). The downward NOx transport occurs primarily in the wintertime polar night jet (PNJ) hence may lead to a characteristic positive dipole ozone signal (higher ozone at solar maximum) in the annual mean. Such a dipole, peaking at 40-45 km near 60°N and 60°S, has been noted in some satellite observations. In this talk we present results of 11-year solar cycle simulations of the Freie Universität Berlin Middle Atmosphere Model with interactive chemistry (FUB-CMAM-CHEM). Variations in NOx transport from the mesosphere were parameterised by including an idealised NOx source at high latitudes above 70 km. The NOx source represents the effect of high-energy electron precipitation associated with intense solar wind streams which lead to decreased NOx (hence increased ozone) near solar maximum. Other NOx sources, associated with low and medium energy electrons arising in the aurora tend to have the opposite effect (increased NOx at solar maximum) and are not included in this study . The model calculates the observed dipole ozone signal which is however stronger than that observed, probably due to the neglect of the compensating effects of low and medium energy electrons. The model further calculates a negative ozone signal in the lower stratosphere (~20 km) near the equator which is also suggested by some satellite observations but occurs a little higher up (25-30 km). Our results imply that the negative ozone signal in the model arises at least partly via a chemical effect in which ozone-destroying chemicals are released from their reservoirs via enhanced insolation at solar maximum. In the mesosphere a decrease in ozone is calculated at solar maximum associated with the classical HOx cycle enhanced via Lyman-alpha photolysis of water vapour.

  6. Anatomy of the Pain Centre waiting list at the Centre hospitalier de l’Université de Montréal (CHUM)

    PubMed Central

    Vargas-Schaffer, Grisell; Rusnov, Ann; Boulanger, Aline

    2013-01-01

    Background Waiting list management at chronic pain clinics has become a serious problem throughout Canada. We analyzed the waiting list at the Centre hospitalier de l’Université de Montréal (CHUM) Pain Centre. Methods The present study is an observational, prospective study. We used a specifically designed survey questionnaire. Survey findings were analyzed with descriptive statistical methods. Results A total of 270 patients were contacted; only 146 were included. Of these, 93 were women and 53 men. The average age was 55.9 years. Fifty-two percent of the patients were referred by a medical specialist; 34% by family physicians; 3% for emergency; and 11% unknown. The mean for pain score was 6.7/10. Seventy-three percent were taking pain killers with an average improvement on their pain score of 52%. Ten percent of respondents were not taking any type of analgesic medication, while 17% were taking over-the-counter drugs. Fifty-three percent of the patients had been suffering from chronic pain for 5 years or less, while 10% had been suffering and awaiting specialized pain treatment for more than 20 years. Conclusion Our data suggests that accessibility to specialized health care is not the sole obstacle to the timely and effective management of chronic pain. Seventy-three percent of the patients were taking some form of pharmaceutical treatment for pain and reported an average improvement rate of 52% on their pain score under medication. Such inconsistency may be attributable to patients’ lack of compliance with their treatment. The World Health Organization Working Group recommended in chronic patients a novel approach to health care, based on patient therapeutic education. Our results show that patients need to acquire self-management skills regarding their chronic conditions. PMID:23874120

  7. Retrospective analysis of laboratory testing at the chiropractic clinic of Université du Québec à Trois-Rivières (UQTR)

    PubMed Central

    Boisvert, Daniel

    2006-01-01

    This study provides data based on the clinical experience of the Université du Québec à Trois-Rivières (UQTR) chiropractic clinic justifying the use of laboratory tests in chiropractic practice. The data was gathered retrospectively over a 51 month period from January 22, 1997 to April 10, 2001. During this period, the UQTR Chiropractic Clinic opened 6571 patient files. The analysis reveals that of the 6571 patients, 1200 (18.27%) underwent laboratory processes or tests. Of these 1200 processes or tests, 676 (56.34%) showed abnormal findings. Of the 676 patients with abnormal findings, 122 (18.05%) cases were serious enough to justify a referral to a medical doctor (general practitioner or specialist) for immediate follow-up. Among these serious conditions, one was a bone neoplastic pathology and one was a case of leukemia. This study emphasizes the significant contribution of laboratory tests in chiropractic practice. Its importance rests not only with teaching purposes, but also rests with the proper assessment of clinical conditions frequently observed in chiropractic practice. Laboratory tests used in a proper context serve not only as a valuable instrument to identify primary and underlying abnormal physiological factors, but also assist the chiropractor in identifying more precisely those cases that require a medical referral. This study also demonstrates that laboratory testing of chiropractic patients is a necessary and essential clinical procedure for complete public protection. It also demonstrates that chiropractors are an essential part of the health team even when patients are under medical supervision. PMID:17549159

  8. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1986

    1986-01-01

    Describes activities, games, experiments, demonstrations, and computer-oriented exercises in all science areas. Topics include energy flow through a marine ecosystem, using 2,4-dichlorophenoxyethanoic acid to demonstrate translocation in plants, use of the dichotomous key, use of leaf yeasts to monitor atmospheric pollution, and others. (JN)

  9. Nuclear Science.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    This document is a report on a course in nuclear science for the high school curriculum. The course is designed to provide a basic but comprehensive understanding of the atom in the light of modern knowledge, and to show how people attempt to harness the tremendous energy liberated through fission and fusion reactions. The course crosses what are…

  10. Science First

    ERIC Educational Resources Information Center

    Comstock, Diane

    2005-01-01

    At the elementary level, when children learn best through hands-on activities, when is the best time to use literacy and make that connection to enhance learning? For teachers involved in Colorado Springs, Colorado, Science Teacher Enhancement Program Unifying the Pikes Peak Region, STEP-uP professional development program for teachers, it is…

  11. Science Journalism

    ERIC Educational Resources Information Center

    Polman, Joseph; Newman, Alan; Farrar, Cathy; Saul, E. Wendy

    2012-01-01

    Much of the National Science Education Standards (NRC 1996), aside from the inquiry and teaching sections, focus on content. The authors' call is instead to build standards that focus on what students need to be scientifically literate in 10 or 15 years. Although a basic understanding of important scientific concepts and an understanding of how

  12. Science Notes.

    ERIC Educational Resources Information Center

    Talbot, Chris; And Others

    1991-01-01

    Twenty science experiments are presented. Topics include recombinant DNA, physiology, nucleophiles, reactivity series, molar volume of gases, spreadsheets in chemistry, hydrogen bonding, composite materials, radioactive decay, magnetism, speed, charged particles, compression waves, heat transfer, Ursa Major, balloons, current, and expansion of

  13. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1990

    1990-01-01

    Presented are 25 science activities on colorations of prey, evolution, blood, physiology, nutrition, enzyme kinetics, leaf pigments, analytical chemistry, milk, proteins, fermentation, surface effects of liquids, magnetism, drug synthesis, solvents, wintergreen synthesis, chemical reactions, multicore cables, diffraction, air resistance,…

  14. Systems Science

    ERIC Educational Resources Information Center

    Christakis, Alexander; Hammond, Debora; Jackson, Michael; Laszlo, Alexander; Mitroff, Ian; Snowden, Dave; Troncale, Len; Carr-Chellman, Alison; Spector, J. Michael; Wilson, Brent

    2013-01-01

    Scholars representing the field of systems science were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Alexander Christakis, Debora Hammond, Michael Jackson, Alexander Laszlo, Ian Mitroff, Dave…

  15. Redirecting science

    SciTech Connect

    Aaserud, F.

    1990-01-01

    This book contains the following chapters. Science policy and fund-raising up to 1934; The Copenhagen spirit at work, late 1920's to mid-1930s; The refugee problem, 1933 to 1935; Experimental biology, late 1920s to 1935; and Consolidation of the transition, 1935 to 1940.

  16. Science Alliance.

    ERIC Educational Resources Information Center

    Baumann, Lorrie; Ribeiro, Mary

    1997-01-01

    Describes the Science Alliance project, a teacher-scientist collaboration where each teacher is given five non-consecutive days of professional development time to meet with a participating scientist, technician, engineer, mathematician, or environmentalist to develop a module of lesson plans that introduce the real world of industry into the…

  17. Skeptical Science.

    ERIC Educational Resources Information Center

    Scott, Alan J.; Barnhart, Carolyn M.; Parejko, Ken S.; Schultz, Forrest S.; Schultz, Steven E.

    2001-01-01

    Discusses the legitimacy of teaching about astrology, extrasensory perception, UFOs, touch therapy, cloning dinosaurs, or any other unusual claims in the classroom. Suggests that bringing unusual claims to the science classroom is an opportunity to motivate students in the principles of scientific thought. (SAH)

  18. Systems Science

    ERIC Educational Resources Information Center

    Christakis, Alexander; Hammond, Debora; Jackson, Michael; Laszlo, Alexander; Mitroff, Ian; Snowden, Dave; Troncale, Len; Carr-Chellman, Alison; Spector, J. Michael; Wilson, Brent

    2013-01-01

    Scholars representing the field of systems science were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Alexander Christakis, Debora Hammond, Michael Jackson, Alexander Laszlo, Ian Mitroff, Dave

  19. Boundless Science

    NASA Astrophysics Data System (ADS)

    Spilhaus, F.

    2009-04-01

    Our science is critical to understanding the future prospects for life. The laboratory for natural sciences encompasses our planet and reaches into the solar system. The forces of nature respect no boundaries. But, we who try to understand these forces are handicapped by national, political, language, religious, and other concocted barriers. These barriers limit both our effectiveness as scientists and our ability to reach those outside our community who need to know what we have uncovered about our environment. An unencumbered worldwide scientific community has been an objective with limited successes for too long. Action began in earnest after the first world war with the formation of the various scientific Unions and ICSU. Fifty years later Keith Runcorn initiated another approach, when he proposed what quickly became EGS and which has grown and evolved with the merger with EUG. To be truly effective we need to communicate and share comfortably with colleagues worldwide. Personal relationships and trust are required. We count on a high level of ethical behavior within our community. We individually must also be constantly vigilant for the encroachment of the manmade barriers that have held back science through time immemorial. Our scientific organizations cannot achieve this alone. They will facilitate, however, the onus is on each of us to reach out and form interlocking informal communities, which will bring our whole planet-wide community together at many overlapping levels. When we achieve this community, our science will more bountiful and better address the needs of human society.

  20. Pathological Science

    NASA Astrophysics Data System (ADS)

    Stone, Sheldon

    2001-09-01

    I discuss examples of what Dr. Irving Langmuir, a Nobel prize winner in Chemistry, called "the science of things that aren't so." Some of his examples are reviewed and others from High Energy Physics are added. It is hoped that discussing these incidents will help us develop an understanding of some potential pitfalls.

  1. Animal Science.

    ERIC Educational Resources Information Center

    VanCleave, Janice

    2001-01-01

    Presents a set of hands-on, outdoor science experiments designed to teach elementary school students about animal adaptation. The experiments focus on: how color camouflage affects an insect population; how spiderlings find a home; and how chameleons camouflage themselves by changing color. (SM)

  2. Brewing Science

    ERIC Educational Resources Information Center

    Pelter, Michael

    2006-01-01

    Following the brewing process from grain to glass, this course uses the biological and chemical principles of brewing to teach science to the nonscience major. Discussion of the scientific aspects of malting, mashing, fermentation, and the making of different beer styles is complemented by laboratory exercises that use scientific methods to

  3. Wyndham Science.

    ERIC Educational Resources Information Center

    Messel, H.

    Described is the Wyndham science component of the program designed for the six years of secondary schooling for students in New South Wales, Australia. A subjective evaluation of the program and suggestions for improving course materials and teaching are given. There are six major sections in the report: (1) a general outline of the structure and…

  4. Subterranean science

    NASA Astrophysics Data System (ADS)

    Paling, Sean; Sadler, Stephen

    2015-05-01

    The deep underground laboratories of the world are no longer the scientific realm of astroparticle physics alone. From Mars rovers to muon tomography, and from radioactive dating to astrobiology, Sean Paling and Stephen Sadler describe the renaissance in the science taking place far beneath our feet.

  5. Nuclear Science.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    This document is a report on a course in nuclear science for the high school curriculum. The course is designed to provide a basic but comprehensive understanding of the atom in the light of modern knowledge, and to show how people attempt to harness the tremendous energy liberated through fission and fusion reactions. The course crosses what are

  6. Science Notes.

    ERIC Educational Resources Information Center

    Shaw, G. W.; And Others

    1989-01-01

    Provides a reading list for A- and S-level biology. Contains several experiments and demonstrations with topics on: the intestine, bullock corneal cells, valences, the science of tea, automated hydrolysis, electronics characteristics, bromine diffusion, enthalpy of vaporization determination, thermometers, pendulums, hovercraft, Bernoulli fluid…

  7. Science Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1986

    1986-01-01

    Describes 26 different activities, experiments, demonstrations, and computer simulations in various topics in science. Includes instructional activities dealing with mural ecology, surface area/volume ratios, energy transfer in ecosystems, electrochemical simulations, alternating and direct current, terminal velocity, measuring the size of the…

  8. Literary Science.

    ERIC Educational Resources Information Center

    Garrison, Megan R.

    2000-01-01

    Explains the use of literacy in science education. Uses "Silent Spring", a book on environmental issues, to encourage students to think about the role of water in balancing the earth's system and possible actions against environmental concerns. Creates an environment for students to discuss their knowledge on the use of the pesticide DDT. (YDS)

  9. Organizational Science

    ERIC Educational Resources Information Center

    Beriwal, Madhu; Clegg, Stewart; Collopy, Fred; McDaniel, Reuben, Jr.; Morgan, Gareth; Sutcliffe, Kathleen; Kaufman, Roger; Marker, Anthony; Selwyn, Neil

    2013-01-01

    Scholars representing the field of organizational science, broadly defined as including many fields--organizational behavior and development, management, workplace performance, and so on--were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might…

  10. Brewing Science

    ERIC Educational Resources Information Center

    Pelter, Michael

    2006-01-01

    Following the brewing process from grain to glass, this course uses the biological and chemical principles of brewing to teach science to the nonscience major. Discussion of the scientific aspects of malting, mashing, fermentation, and the making of different beer styles is complemented by laboratory exercises that use scientific methods to…

  11. Science Notes.

    ERIC Educational Resources Information Center

    Shaw, G. W.; And Others

    1989-01-01

    Provides a reading list for A- and S-level biology. Contains several experiments and demonstrations with topics on: the intestine, bullock corneal cells, valences, the science of tea, automated hydrolysis, electronics characteristics, bromine diffusion, enthalpy of vaporization determination, thermometers, pendulums, hovercraft, Bernoulli fluid

  12. Science Journalism

    ERIC Educational Resources Information Center

    Polman, Joseph; Newman, Alan; Farrar, Cathy; Saul, E. Wendy

    2012-01-01

    Much of the National Science Education Standards (NRC 1996), aside from the inquiry and teaching sections, focus on content. The authors' call is instead to build standards that focus on what students need to be scientifically literate in 10 or 15 years. Although a basic understanding of important scientific concepts and an understanding of how…

  13. Kaleidoscope Science.

    ERIC Educational Resources Information Center

    Janes, Patricia

    2002-01-01

    Presents a collection of science activities that have elementary students investigate how color can trick the eye and the brain. The activities involve working with contrasting colors, creating a rainbow, and exploring the connection between colors and words. An instructor reproducible features two color activities. (SM)

  14. Cognitive Science.

    ERIC Educational Resources Information Center

    Cocking, Rodney R.; Mestre, Jose P.

    The focus of this paper is on cognitive science as a model for understanding the application of human skills toward effective problem-solving. Sections include: (1) "Introduction" (discussing information processing framework, expert-novice distinctions, schema theory, and learning process); (2) "Application: The Expert-Novice Paradigm as a Means…

  15. Cognitive Science.

    ERIC Educational Resources Information Center

    Soni, P. Sarita, Ed.; Carmichael, Ann G., Ed.

    1993-01-01

    This theme issue features five articles profiling Indiana University faculty whose work on various campuses continues to broaden and advance knowledge about cognitive science. The articles in the journal are: "A Matter of Time" (Karen Grooms) which discusses the work of Robert F. Port; "Perceiving as a Complex System" (Tom Tierney) which profiles…

  16. Science Notes.

    ERIC Educational Resources Information Center

    Talbot, Chris; And Others

    1991-01-01

    Twenty science experiments are presented. Topics include recombinant DNA, physiology, nucleophiles, reactivity series, molar volume of gases, spreadsheets in chemistry, hydrogen bonding, composite materials, radioactive decay, magnetism, speed, charged particles, compression waves, heat transfer, Ursa Major, balloons, current, and expansion of…

  17. Les neuropeptides gastro-intestinaux cibles des effets des rayonnements ionisants : altérations fonctionnelles

    NASA Astrophysics Data System (ADS)

    Linard, C.; Esposito, V.; Wysocki, J.; Griffiths, N. M.

    1998-04-01

    The symptoms associated with exposure to ionizing radiation are nausea, vomiting, diarrhoea. The response of the gut is complex involving modifications of motility and fluid and electrolyte transport. Gastrointestinal regulatory peptides have an important role in these functions. This study showed that radiation-induced tissue variations of neuropeptides have some repercussions on intestinal biological activity of these peptides soon after irradiation. In addition such modifications are also seen a few years after irradiation. Les symptômes associés à l'exposition aux rayonnements ionisants sont des nausées, vomissements et diarrhées. La réponse du système digestif est complexe, impliquant des modifications de la motilité et du transport d'eau et d'électrolytes. les neuropeptides gastro-intestinaux ont un rôle important dans ces fonctions. Cette étude montre que les variations tissulaires de ces neuropeptides induites par l'irradiation ont des répercussions sur l'activité biologique intestinale pour des temps précoces mais que ces perturbations sont encore visibles quelques années après l'irradiation.

  18. Early Science Results from the Dark Energy Survey

    NASA Astrophysics Data System (ADS)

    Ross, Ashley

    2015-04-01

    The Dark Energy Survey (DES) is a next-generation large galaxy survey designed to unravel the mystery of the nature of the dark energy that powers the current accelerated expansion of the Universe. The DES collaboration built and participated in the installation and commissioning of DECam, a 570 mega-pixel optical and near-infrared camera with a large 3 deg2 field of view, set at the prime focus of the Víctor M. Blanco 4-meter telescope in at the Cerro Tololo Inter-American Observatory in Chile. Using DECam, DES will map 5000 deg2 to a depth IAB ~ 24 and observe designated supernova survey fields at high cadence. These data will allow DES to measure positions, approximate redshifts, and shapes for 300 million galaxies, the light-curves of several thousand supernovae, and the masses of tens of thousands of galaxy clusters. Using these data, DES will use four main probes to study the properties of dark energy: galaxy clustering on large scales, weak gravitational lensing, galaxy-cluster abundance, and supernova distances. I describe the early progress of the survey and provide highlights of the science analyses that have been completed so far. These include: large-scale galaxy clustering measurements; significant detection of a cross-correlation with SPT CMB lensing maps; galaxy-shear and shear-shear correlation function measurements; discoveries of super-luminous supernovae, dozens of strong lenses, and redshift > 6 quasars; and characterization of DES galaxy clusters and SNe1a light-curves.

  19. Etude des defauts microscopiques et des proprietes optiques, electroniques et magnetiques du compose neodyme cerium oxyde de cuivre

    NASA Astrophysics Data System (ADS)

    Richard, Pierre

    La presente these, qui combine des mesures de diffusion Raman, de transmission infrarouge, de conductivite hyperfrequence et d'interferometrie ultrasonore sur les composes Nd 2-xCexCuO 4, traite des defauts d'oxygene, ainsi que des proprietes optiques, electroniques et magnetiques de ces materiaux. Les resultats experimentaux obtenus sont correles avec plusieurs donnees experimentales disponibles dans la litterature. D'abord, la caracterisation des modes Raman et des niveaux d'energie de champ cristallin de l'ion Nd3+ au moyen de techniques optiques, en fonction du dopage en cerium et du contenu en oxygene, permettent de conclure a la presence de defauts lies a une non-stoechiometrie en oxygene dans ces composes. En effet, des excitations de champ cristallin assignees a des ions Nd3+ en sites irreguliers sont observees, en plus des bandes d'absorption associees aux ions Nd3+ en site regulier, dans les spectres correspondant aux multiplets 4I11/2, 4I13/2 et 4I 15/2 de l'ion Nd3+. Les resultats experimentaux indiquent que, contrairement a la croyance largement repandue, les oxygenes apicaux, bien que presents dans les echantillons dopes, ne sont pas enleves lors du processus de reduction des echantillons necessaire pour faire apparaitre la supraconductivite dans cette famille de cuprates. Au contraire, des lacunes d'oxygene, dont le type varie en fonction du dopage, sont creees lors de ce processus. En particulier, il est montre dans ce travail que la reduction des echantillons dopes de maniere optimale conduit a la creation de lacunes d'oxygene dans les plans CuO2. Les consequences de telles lacunes sont largement discutees. En outre, il est suggere que de telles lacunes sont responsables de la perte de l'ordre antiferromagnetique a longue portee des ions Cu2+. Finalement, l'interaction d'echange anisotrope Nd3+-Cu 2+ dans le compose nondope est caracterisee au moyen de la transmission infrarouge sous champ magnetique. L'eclatement des doublets de Kramers mesure experimentalement est compare, en fonction de l'intensite et de l'orientation du champ magnetique externe, a des calculs d'effet Zeeman. Alors, que les calculs d'effet Zeeman ne coincident pas avec les donnees experimentales pour un champ applique perpendiculairement aux plans CuO 2, ceux-ci sont en accord avec les resultats de transmission infrarouge pour des champs superieurs a 4 T appliques parallelement a ces plans, indiquant une suppression apparente de l'interaction d'echange anisotrope Nd3+-Cu 2+ dans de telles conditions. (Abstract shortened by UMI.)

  20. IFLA General Conference, 1987. Division of Special Libraries. Science and Technology Libraries Section. Papers.

    ERIC Educational Resources Information Center

    International Federation of Library Associations, The Hague (Netherlands).

    The six papers in this collection focus on science and technology libraries: (1) "Human Aspects of Electronically-Stored Information: The Library User" (A. J. Meadows, United Kingdom); (2) "Untersuchung Menschlicher Aspekte bei den Elektronisch Gespeicherten Informationen: Ansichten des Leiters eines Bibliothekskollektives = Human Aspects of

  1. IFLA General Conference, 1987. Division of Special Libraries. Science and Technology Libraries Section. Papers.

    ERIC Educational Resources Information Center

    International Federation of Library Associations, The Hague (Netherlands).

    The six papers in this collection focus on science and technology libraries: (1) "Human Aspects of Electronically-Stored Information: The Library User" (A. J. Meadows, United Kingdom); (2) "Untersuchung Menschlicher Aspekte bei den Elektronisch Gespeicherten Informationen: Ansichten des Leiters eines Bibliothekskollektives = Human Aspects of…

  2. 1. ORIGINAL STONE ARCH BRIDGE OVER THE DES PLAINES RIVER ...

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

    1. ORIGINAL STONE ARCH BRIDGE OVER THE DES PLAINES RIVER AT NINTH STREET IN LOCKPORT. THE BRIDGE WAS BUILT ABOUT 1865. NOTE METAL CLAMP ON THE NEAR PIER AND THE 20TH CENTURY REINFORCED CONCRETE ADDITION. - Lockport Historic District, Stone Arch Bridge, Spanning Des Plaines River at Ninth Street, Lockport, Will County, IL

  3. Vers des boites quantiques a base de graphene

    NASA Astrophysics Data System (ADS)

    Branchaud, Simon

    Le graphene est un materiau a base de carbone qui est etudie largement depuis 2004. De tres nombreux articles ont ete publies tant sur les proprietes electroniques, qu'optiques ou mecaniques de ce materiel. Cet ouvrage porte sur l'etude des fluctuations de conductance dans le graphene, et sur la fabrication et la caracterisation de nanostructures gravees dans des feuilles de ce cristal 2D. Des mesures de magnetoresistance a basse temperature ont ete faites pres du point de neutralite de charge (PNC) ainsi qu'a haute densite electronique. On trouve deux origines aux fluctuations de conductance pres du PNC, soit des oscillations mesoscopiques provenant de l'interference quantique, et des fluctuations dites Hall quantique apparaissant a plus haut champ (>0.5T), semblant suivre les facteurs de remplissage associes aux monocouches de graphene. Ces dernieres fluctuations sont attribuees a la charge d'etats localises, et revelent un precurseur a l'effet Hall quantique, qui lui, ne se manifeste pas avant 2T. On arrive a extraire les parametres caracterisant l'echantillon a partir de ces donnees. A la fin de cet ouvrage, on effectue des mesures de transport dans des constrictions et ilots de graphene, ou des boites quantiques sont formees. A partir de ces mesures, on extrait les parametres importants de ces boites quantiques, comme leur taille et leur energie de charge.

  4. Science Curriculum Framework. Revised.

    ERIC Educational Resources Information Center

    Arkansas State Dept. of Education, Little Rock.

    This document presents the revised Arkansas Science Curriculum Framework (1999), which replaces the Science Curriculum Framework of 1994. Three strands--physical science systems, life science systems, and Earth science/space science systems--were identified using an integrated approach to provide guidance in the science curriculum. A glossary and…

  5. Portraying Real Science in Science Communication

    ERIC Educational Resources Information Center

    van Dijk, Esther M.

    2011-01-01

    In both formal and informal settings, not only science but also views on the nature of science are communicated. Although there probably is no singular nature shared by all fields of science, in the field of science education it is commonly assumed that on a certain level of generality there is a consensus on many features of science. In this…

  6. Science News and the Science Classroom

    ERIC Educational Resources Information Center

    McCullough, Laura

    2006-01-01

    Using "Science News" as a teaching tool promotes writing about science, talking about science, and broadening students' views about what science is. This article describes an ongoing assignment in which students choose one article from "Science News" each week and write a brief summary and explanation of why they picked that article. (Contains 1…

  7. Portraying Real Science in Science Communication

    ERIC Educational Resources Information Center

    van Dijk, Esther M.

    2011-01-01

    In both formal and informal settings, not only science but also views on the nature of science are communicated. Although there probably is no singular nature shared by all fields of science, in the field of science education it is commonly assumed that on a certain level of generality there is a consensus on many features of science. In this

  8. Anisotropie des coefficients de diffusion dans des cristaux liquides discotiques hexagonaux

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Gharbia, M.; Gharbi, A.

    1994-06-01

    The diffusion constants of dyes in several hexagonal discotic liquid crystals are measured and discussed. For all the liquid crystals studied, these constants are anisotropic : the diffusion in the direction parallel to the columns is faster than that in the perpendicular plane (frac{D_allel}{D_perp}>1). The effects of the length and shape of the chains bound to the triphenylene discs are shown. The effect of the dye molecular size is also described. The study of the diffusion coefficients of hexapentoxytriphenylene (C5HET) as a function of temperature has shown that the activation energies along the columns and perpendicular to the columns are comparable. The main features of dye diffusion in the hexagonal columnar liquid crystals studied are similar to those reported in nematic phases. Les mesures des constantes de diffusion de colorants dans plusieurs cristaux liquides discotiques hexagonaux sont présentées et discutées. Pour tous les cristaux liquides étudiés, ces constantes présentent une anisotropie, avec une diffusion plus rapide parallèlement aux colonnes que perpendiculairement à celles-ci (frac{D_allel}{D_perp}>1). Des effets de longueur et de forme des chaînes branchées sur les disques de triphénylène sont mis en évidence. Il en est de même pour la taille des molécules de colorants. L'étude en fonction de la température a montré que dans le cas de l'hexapentoxytriphénylène (C5HET), les énergies d'activation dans les directions parallèle et perpendiculaire aux colonnes sont comparables. Les caractéristiques de la diffusion de colorants dans les cristaux liquides colonnaires hexagonaux étudiés sont semblables à celles des nématiques.

  9. Etude de la dynamique des porteurs dans des nanofils de silicium par spectroscopie terahertz

    NASA Astrophysics Data System (ADS)

    Beaudoin, Alexandre

    Ce memoire presente une etude des proprietes de conduction electrique et de la dynamique temporelle des porteurs de charges dans des nanofils de silicium sondes par rayonnement terahertz. Les cas de nanofils de silicium non intentionnellement dopes et dopes type n sont compares pour differentes configurations du montage experimental. Les mesures de spectroscopie terahertz en transmission montre qu'il est possible de detecter la presence de dopants dans les nanofils via leur absorption du rayonnement terahertz (˜ 1--12 meV). Les difficultes de modelisation de la transmission d'une impulsion electromagnetique dans un systeme de nanofils sont egalement discutees. La detection differentielle, une modification au systeme de spectroscopie terahertz, est testee et ses performances sont comparees au montage de caracterisation standard. Les instructions et des recommendations pour la mise en place de ce type de mesure sont incluses. Les resultats d'une experience de pompe optique-sonde terahertz sont egalement presentes. Dans cette experience, les porteurs de charge temporairement crees suite a l'absorption de la pompe optique (lambda ˜ 800 nm) dans les nanofils (les photoporteurs) s'ajoutent aux porteurs initialement presents et augmentent done l'absorption du rayonnement terahertz. Premierement, l'anisotropie de l'absorption terahertz et de la pompe optique par les nanofils est demontree. Deuxiemement, le temps de recombinaison des photoporteurs est etudie en fonction du nombre de photoporteurs injectes. Une hypothese expliquant les comportements observes pour les nanofils non-dopes et dopes-n est presentee. Troisiemement, la photoconductivite est extraite pour les nanofils non-dopes et dopes-n sur une plage de 0.5 a 2 THz. Un lissage sur la photoconductivite permet d'estimer le nombre de dopants dans les nanofils dopes-n. Mots-cles: nanofil, silicium, terahertz, conductivite, spectroscopie, photoconductivite.

  10. Board Adds Two New Members With Expertise in Communication and Science Policy

    NASA Astrophysics Data System (ADS)

    McEntee, Christine W.

    2010-11-01

    AGU's Board of Directors approved two new members during a special teleconference on 8 November. The appointments are related to AGU's strategic plan goal of addressing science and society. Specifically, they add to AGU's expertise in science communication and policy outreach. Author Chris Mooney and policy advisor Floyd DesChamps join AGU's Board of Directors immediately and will serve the remainder of the 2010-2012 term.

  11. Etude du processus de changement vecu par des familles ayant decide d'adopter volontairement des comportements d'attenuation des changements climatiques

    NASA Astrophysics Data System (ADS)

    Leger, Michel T.

    Les activites humaines energivores telles l'utilisation intensive de l'automobile, la surconsommation de biens et l'usage excessif d'electricite contribuent aux changements climatiques et autres problemes environnementaux. Bien que plusieurs recherches rapportent que l'etre humain est de plus en plus conscient de ses impacts sur le climat de la planete, ces memes recherches indiquent qu'en general, les gens continuent a se comporter de facon non ecologique. Que ce soit a l'ecole ou dans la communaute, plusieurs chercheurs en education relative a l'environnement estiment qu'une personne bien intentionnee est capable d'adopter des comportements plus respectueux de l'environnement. Le but de cette these etait de comprendre le processus d'integration de comportements d'attenuation des changements climatiques dans des familles. A cette fin, nous nous sommes fixe deux objectifs : 1) decrire les competences et les procedes qui favorisent l'adoption de comportements d'attenuation des changements climatiques dans des familles et 2) decrire les facteurs et les dynamiques familiales qui facilitent et limitent l'adoption de comportements d'attenuation des changements climatiques dans des familles. Des familles ont ete invitees a essayer des comportements personnels et collectifs d'attenuation des changements climatiques de sorte a integrer des modes de vie plus ecologiques. Sur une periode de huit mois, nous avons suivi leur experience de changement afin de mieux comprendre comment se produit le processus de changement dans des familles qui decident volontairement d'adopter des comportements d'attenuation des changements climatiques. Apres leur avoir fourni quelques connaissances de base sur les changements climatiques, nous avons observe le vecu de changement des familles durant huit mois d'essais a l'aide de journaux reflexifs, d'entretiens d'explicitation et du journal du chercheur. La these comporte trois articles scientifiques. Dans le premier article, nous presentons une recension des ecrits sur le changement de comportement en environnement. Nous explorons egalement la famille comme systeme fonctionnel de sorte a mieux comprendre ce contexte d'action environnementale qui est, a notre connaissance, peu etudie. Dans le deuxieme article, nous presentons nos resultats de recherche concernant les facteurs d'influence observes ainsi que les competences manifestees au cours du processus d'adoption de nouveaux comportements environnementaux dans trois familles. Enfin, le troisieme article presente les resultats du cas d'une quatrieme famille ou les membres vivent depuis longtemps des modes de vie ecologique. Dans le cadre d'une demarche d'analyse par theorisation ancree, l'etude de ce cas modele nous a permis d'approfondir les categories conceptuelles identifiees dans le deuxieme article de sorte a produire une modelisation de l'integration de comportements environnementaux dans le contexte de la famille. Les conclusions degagees grace a la recension des ecrits nous ont permis d'identifier les elements qui pourraient influencer l'adoption de comportements environnementaux dans des familles. La recension a aussi permis une meilleure comprehension des divers facteurs qui peuvent affecter l'adoption de comportements environnementaux et, enfin, elle a permis de mieux cerner le phenomene de changement de comportement dans le contexte de la famille consideree comme un systeme. En appliquant un processus d'analyse inductif, a partir de nos donnees qualitatives, les resultats de notre etude multi-cas nous ont indique que deux construits conceptuels semblent influencer l'adoption de comportements environnementaux en famille : 1) les valeurs biospheriques communes au sein de la famille et 2) les competences collectivement mises a profit collectivement durant l'essai de nouveaux comportements environnementaux. Notre modelisation du processus de changement dans des familles indique aussi qu'une dynamique familiale collaborative et la presence d'un groupe de soutien exterieur sont deux elements conceptuels qui tendent a influencer les deux principaux construits et, par ce fait, tendent a augmenter les chances d'integrer de nouveaux comportements environnementaux dans des familles. En conclusion, nous presentons les limites de notre recherche ainsi que des pistes pour des recherches futures. Notamment, nous recommandons que l'ecole accueille les familles des eleves dans le cadre d'activites d'education a l'environnement ou les freres, les soeurs et les parents des eleves puissent apprendre ensemble, a l'ecole. Par exemple, nous recommandons la conduite en ERE d'une recherche action portant sur l'apprentissage intergenerationnel de nouveaux comportements dans le contexte de la famille. Mots-cles : education relative a l'environnement, comportement environnemental en famille, changement de comportement en famille, valeurs biospheriques, competences d'action.

  12. Hans Bethe : Des etoiles a la bombe

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    1996-06-01

    Il comprit le premier comment brillent les etoiles. Il fut aussi de cette poignee de scientifiques qui, dans le secret de Los Alamos, mirent au point la tristement celebre bombe atomique. Hans Bethe est l'un des derniers geants qui auront marque la physique de ce siecle d'une empreinte indelebile. C'est dans le bureau 01 du prestigieux laboratoire Kellog de l'institut Caltech qu'il a bien voulu retracer pour nous son impressionnante carriere, et revenir sur les motivations qui ont guide ses pas.

  13. Elektrische Phnomene des Krpers und ihre Detektion

    NASA Astrophysics Data System (ADS)

    Bolz, Armin; Kikillus, Nicole; Moor, Claudius

    Im menschlichen Krper verfgen sowohl Nerven- als auch Muskelzellen ber die Eigenschaft, intra- und extrazellulre Ionenkonzentrationen zu verschieben und damit die Potenzialverteilung in ihrer Umgebung zu beeinflussen. ber unterschiedliche Synchronisationsverfahren sind makroskopische Zellverbnde zustzlich in der Lage, koordiniert ihre Felder zu verndern und somit auch signifikante, an der Krperoberflche messbare elektrische Signale zu erzeugen. Das vorliegende Kapitel beschreibt zunchst die elektrophysiologischen Grundlagen elektrischer Signale des menschlichen Krpers, die Synchronisationsmechanismen und die daraus entstehenden Felder, insbesondere das Elektrokardiogramm (EKG), das Elektroenzephalogramm (EEG) sowie das Elektromyogramm (EMG). Im Anschluss daran werden die wesentlichen Grundlagen der Messtechnik zur Erfassung bioelektrischer Phnomene erlutert. Einige Beispielapplikationen runden diesen Beitrag ab.

  14. Le traitement familial des enfants et des adolescents anorexiques : Des lignes directrices pour le médecin communautaire

    PubMed Central

    Findlay, S; Pinzon, J; Taddeo, D; Katzman, DK

    2010-01-01

    L’anorexie mentale (AM) est une maladie grave qui met la vie en danger et qui fait généralement son apparition pendant l’adolescence. Les données probantes au sujet du traitement optimal de l’AM chez les enfants et les adolescents sont en croissance, mais il reste beaucoup à apprendre. Même si les démarches thérapeutiques actuelles varient au Canada et ailleurs, les données jusqu’à présent indiquent que le traitement familial (TF) est le plus efficace pour les enfants et les adolescents anorexiques. Un élément essentiel du modèle de TF, c’est que les parents sont investis de la responsabilité de rétablir la santé physique de leur enfant et de s’assurer de la reprise complète de son poids. Le médecin qui comprend les principes fondamentaux et la philosophie du TF peut mettre en place les éléments de cette intervention fondée sur des faits probants auprès des jeunes patients anorexiques et de leur famille.

  15. Heliophysics Science

    NASA Astrophysics Data System (ADS)

    Austin, M.; Schrjver, K.; Siscoe, G. L.; Bhattacharjee, A.; Longcope, D. W.; Sojka, J. J.; Guhathakurta, M.

    2009-12-01

    HELIOPHYSICS SUMMER SCHOOLS: NASA Living With a Star and the University Corporation for Atmospheric Research, Visiting Scientist Programs sponsor the Heliophysics Summer Schools to build this new field of science. The series of summer schools, started in 2007, help graduate students and scientists learn and develop the science of heliophysics as a broad, coherent discipline that reaches in space from the Earth's troposphere to the depths of the Sun, and in time from the formation of the solar system to the distant future. The first three years of the school will result in three textbooks for use at universities worldwide. Subsequent years will both teach other generations of students and develop the complementary materials that support teaching of heliophysics at both graduate and undergraduate levels. Heliophysics is a developing scientific discipline integrating studies of the Sun’s variability, the surrounding heliosphere, and climatic environments. Over the past few centuries, our understanding of how the Sun drives space weather and climate on the Earth and other planets has advanced at an ever-increasing rate. The first textbook, (Heliophysics I Plasma Physics of the Local Cosmos, edited by Carolus J. Schrijver, Lockheed Martin and George L. Siscoe, Boston University) integrates such diverse topics for the first time as a coherent intellectual discipline. It emphasizes the physical processes coupling the Sun and Earth, allowing insights into the interaction of the solar wind and radiation with the Earth’s magnetic field, atmosphere and climate system. It provides a core resource for advanced undergraduates and graduates, and also constitutes a foundational reference for researchers in heliophysics, astrophysics, plasma physics, space physics, solar physics, aeronomy, space weather, planetary science and climate science. HELIOPHYSICS POSTDOCTORAL PROGRAM: Hosts and applicants are invited to apply to a new postdoctoral fellowship program designed to train the next generation of researchers in the emerging field of Heliophysics. Two major topics of focus for LWS are the science of space weather and of the Sun-climate connection. Preference will be given to applicants whose proposed research addresses one of these two foci; but any research program relevant to LWS will be considered. Since the goal of this fellowship program is to train Sun-Earth system researchers, preference will also be given to research projects that cross the traditional Heliophysics subdomains of the Sun, heliosphere, magnetosphere, and ionosphere/upper atmosphere, as well as Sun-climate investigations. Host institutions and mentoring scientists will play critical roles. Hosts may post information about their research on a central database for this program: www.vsp.ucar.edu/HeliophysicsScience.

  16. The Science in Science Fiction.

    ERIC Educational Resources Information Center

    Nicholls, Peter, Ed.

    This 12-chapter book discusses the scientific facts behind the ideas included in the novels of Robert Heinlein, Isaac Asimov, Frederik Pohl, Arthur C. Clark and other science fiction writers. Areas explored in the first 11 chapters include: exploration of deep space; energy and exotic power sources; likelihood of extra-terrestrial life and the…

  17. Science Shorts: "Sounds" Like Science

    ERIC Educational Resources Information Center

    Arnone, Kathryn; Morris, Bethany

    2014-01-01

    It seems each new school year brings its own opportunities to grow as an educator. As teachers in a STEM focused school that serves primarily at-risk students, the authors face a new challenge in rethinking their instruction to align with the "Next Generation Science Standards". This involves changing the focus of units previously taught…

  18. Science Centres and Science Learning.

    ERIC Educational Resources Information Center

    Rennie, Leonie J.; McClafferty, Terence P.

    1996-01-01

    Focuses on the interactive science center and its history over the last four decades. Traces the original idea to Francis Bacon. Recommends the use of cross-site studies to develop a model of learning in this setting. Contains 141 references. (DDR)

  19. The Science in Science Fiction.

    ERIC Educational Resources Information Center

    Nicholls, Peter, Ed.

    This 12-chapter book discusses the scientific facts behind the ideas included in the novels of Robert Heinlein, Isaac Asimov, Frederik Pohl, Arthur C. Clark and other science fiction writers. Areas explored in the first 11 chapters include: exploration of deep space; energy and exotic power sources; likelihood of extra-terrestrial life and the

  20. Science Shorts: "Sounds" Like Science

    ERIC Educational Resources Information Center

    Arnone, Kathryn; Morris, Bethany

    2014-01-01

    It seems each new school year brings its own opportunities to grow as an educator. As teachers in a STEM focused school that serves primarily at-risk students, the authors face a new challenge in rethinking their instruction to align with the "Next Generation Science Standards". This involves changing the focus of units previously taught

  1. School Science and Public Understanding of Science.

    ERIC Educational Resources Information Center

    Fensham, Peter J.; Harlen, Wynne

    1999-01-01

    Traces how the idea of measuring the connection between school science and public awareness of science has emerged. Describes the Program for International Student Achievement (PISA) project's indicators of educational progress in science. Contains 28 references. (Author/WRM)

  2. Composing Science

    NASA Astrophysics Data System (ADS)

    Atkins, Leslie

    2015-03-01

    The course Scientific Inquiry at California State University was developed by faculty in biology, physics and English to meet ``writing proficiency'' requirements for non-science majors. Drawing from previous work in composition studies, the position that we take in this course is that we should be engaging students in writing that replicates the work that writing does in science, rather than replicating the particular structural conventions characteristic of scientific writing. That is, scientists use writing to have, remember, share, vet, challenge, and stabilize ideas, and our course requires students use writing to achieve those aims, rather than produce writing that obeys particular conventions of scientific writing. This talk will describe how we have integrated findings from composition studies with a course on scientific inquiry, and provide examples of how scientific communication has resulted from this dialogue. Funding by NSF #1140860.

  3. Computer sciences

    NASA Technical Reports Server (NTRS)

    Smith, Paul H.

    1988-01-01

    The Computer Science Program provides advanced concepts, techniques, system architectures, algorithms, and software for both space and aeronautics information sciences and computer systems. The overall goal is to provide the technical foundation within NASA for the advancement of computing technology in aerospace applications. The research program is improving the state of knowledge of fundamental aerospace computing principles and advancing computing technology in space applications such as software engineering and information extraction from data collected by scientific instruments in space. The program includes the development of special algorithms and techniques to exploit the computing power provided by high performance parallel processors and special purpose architectures. Research is being conducted in the fundamentals of data base logic and improvement techniques for producing reliable computing systems.

  4. Simulation de l'accretion de glace sur un obstacle bidimensionnel par la methode des bissectrices et par la modelisation des ruisselets et des gouttes de surface

    NASA Astrophysics Data System (ADS)

    Fortin, Guy

    Le LIMA (Laboratoire International des Materiaux Antigivre) en collaboration avec le CIRA (Italian Aerospace Research Centre) a developpe un logiciel simulant l'accretion de la glace en regimes sec et humide sur un objet bidimensionnel fixe. L'approche utilisee s'appuie sur les travaux de Lozowski pour les bilans energetiques, sur une etude du comportement du film d'eau, des ruisselets et des gouttes de surface pour le calcul des rugosites et des masses d'eau residuelle, ainsi que sur une methode de bissectrice pour l'evolution de la surface de glace. La contribution du CIRA a ete de fournir le logiciel pour le calcul des ecoulements et de la captation. Le bilan energetique base sur la conservation de l'energie est la sommation de la chaleur latente de fusion, d'evaporation et de sublimation, du rechauffement adiabatique et cinetique, et des pertes de chaleur par convection et conduction, ainsi que de l'evolution thermodynamique de l'eau de son etat initial a son etat final. La densite de la glace, qui a un impact important sur la simulation, est calculee a partir d'une correlation empirique developpee avec les cylindres tournants. En se basant sur les travaux de Al-Khalil et Hansman, le comportement des gouttes en regimes sec et humide a ete decrit analytiquement, ce qui a mene a determiner la hauteur maximale que peuvent atteindre les gouttes avant mouvement. Cette hauteur, appelee hauteur de mouvement, permet de determiner l'etat de l'eau sur la surface (film, ruisselets ou gouttes), ainsi que la hauteur des rugosites lorsque l'eau existe sous forme de gouttes ou de ruisselets. La hauteur de mouvement est determinee par l'equilibre entre les forces de cisaillement, induites par les effets aerodynamiques et gravitationnels evalues pour une goutte non deformee, et la force de cisaillement, induite par la tension de surface et la deformation de la goutte. Elle a ete validee en laboratoire et la precision obtenue pour la partie aerodynamique et gravitationnelle est de 80%. L'etude de la vague qui se forme sur le film a permis de determiner la hauteur des rugosites lorsque l'eau existe sous forme de film. La masse d'eau residuelle est calculee a partir des modeles analytiques elabores selon l'etat de surface et la hauteur de mouvement. (Abstract shortened by UMI.)

  5. Space science

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A fact sheet on the NASA space science program is presented. Some of the subjects considered include the following: (1) the Orbiting Astronomical Observatory, (2) the Orbiting Solar Observatory, (3) the Small Astronomy Satellite, (4) lunar programs, (5) planetary programs using the Mariner, Pioneer 10, and Viking space probes, and (6) the Scout, Thor-Delta, and Atlas-Centaur launch vehicles. For each program there is a description of the effort, the schedule, management, program officials, and funding aspects in outline form.

  6. Preservice Science Teachers' Science Teaching Orientations and Beliefs about Science

    ERIC Educational Resources Information Center

    Kind, Vanessa

    2016-01-01

    This paper offers clarification of science teacher orientations as a potential component of pedagogical content knowledge. Science teaching orientations and beliefs about science held by 237 preservice science teachers were gathered via content-specific vignettes and questionnaire, respectively, prior to participation in a UK-based teacher

  7. Preservice Science Teachers' Science Teaching Orientations and Beliefs about Science

    ERIC Educational Resources Information Center

    Kind, Vanessa

    2016-01-01

    This paper offers clarification of science teacher orientations as a potential component of pedagogical content knowledge. Science teaching orientations and beliefs about science held by 237 preservice science teachers were gathered via content-specific vignettes and questionnaire, respectively, prior to participation in a UK-based teacher…

  8. Modelisation microstructurale en fatigue/fluage a froid des alliages de titane quasi alpha par le modele des automates cellulaires

    NASA Astrophysics Data System (ADS)

    Boutana, Mohammed Nabil

    Les proprietes d'emploi des alliages de titane sont extremement dependantes a certains aspects des microstructures developpees lors de leur elaboration. Ces microstructures peuvent etre fortement heterogenes du point de vue de leur orientation cristallographique et de leur repartition spatiale. Leurs influences sur le comportement du materiau et son endommagement precoce sont des questions qui sont actuellement soulevees. Dans le present projet de doctorat on chercher a repondre a cette question mais aussi de presenter des solutions tangibles quant a l'utilisation securitaire de ces alliages. Un nouveau modele appele automate cellulaire a ete developpe pour simuler le comportement mecanique des alliages de titane en fatigue-fluage a froid. Ces modeles ont permet de mieux comprendre la correlation entre la microstructure et le comportement mecanique du materiau et surtout une analyse detaillee du comportement local du materiau. Mots-cles: Automate cellulaire, fatigue/fluage, alliage de titane, inclusion d'Eshelby, modelisation

  9. Specialized science.

    PubMed

    Casadevall, Arturo; Fang, Ferric C

    2014-04-01

    As the body of scientific knowledge in a discipline increases, there is pressure for specialization. Fields spawn subfields that then become entities in themselves that promote further specialization. The process by which scientists join specialized groups has remarkable similarities to the guild system of the middle ages. The advantages of specialization of science include efficiency, the establishment of normative standards, and the potential for greater rigor in experimental research. However, specialization also carries risks of monopoly, monotony, and isolation. The current tendency to judge scientific work by the impact factor of the journal in which it is published may have roots in overspecialization, as scientists are less able to critically evaluate work outside their field than before. Scientists in particular define themselves through group identity and adopt practices that conform to the expectations and dynamics of such groups. As part of our continuing analysis of issues confronting contemporary science, we analyze the emergence and consequences of specialization in science, with a particular emphasis on microbiology, a field highly vulnerable to balkanization along microbial phylogenetic boundaries, and suggest that specialization carries significant costs. We propose measures to mitigate the detrimental effects of scientific specialism. PMID:24421049

  10. Specialized Science

    PubMed Central

    Fang, Ferric C.

    2014-01-01

    As the body of scientific knowledge in a discipline increases, there is pressure for specialization. Fields spawn subfields that then become entities in themselves that promote further specialization. The process by which scientists join specialized groups has remarkable similarities to the guild system of the middle ages. The advantages of specialization of science include efficiency, the establishment of normative standards, and the potential for greater rigor in experimental research. However, specialization also carries risks of monopoly, monotony, and isolation. The current tendency to judge scientific work by the impact factor of the journal in which it is published may have roots in overspecialization, as scientists are less able to critically evaluate work outside their field than before. Scientists in particular define themselves through group identity and adopt practices that conform to the expectations and dynamics of such groups. As part of our continuing analysis of issues confronting contemporary science, we analyze the emergence and consequences of specialization in science, with a particular emphasis on microbiology, a field highly vulnerable to balkanization along microbial phylogenetic boundaries, and suggest that specialization carries significant costs. We propose measures to mitigate the detrimental effects of scientific specialism. PMID:24421049

  11. Communicating Science

    NASA Astrophysics Data System (ADS)

    Holland, G. J.; McCaffrey, M. S.; Kiehl, J. T.; Schmidt, C.

    2010-12-01

    We are in an era of rapidly changing communication media, which is driving a major evolution in the modes of communicating science. In the past, a mainstay of scientific communication in popular media was through science “translators”; science journalists and presenters. These have now nearly disappeared and are being replaced by widespread dissemination through, e.g., the internet, blogs, YouTube and journalists who often have little scientific background and sharp deadlines. Thus, scientists are required to assume increasing responsibility for translating their scientific findings and calibrating their communications to non-technical audiences, a task for which they are often ill prepared, especially when it comes to controversial societal issues such as tobacco, evolution, and most recently climate change (Oreskes and Conway 2010). Such issues have been politicized and hi-jacked by ideological belief systems to such an extent that constructive dialogue is often impossible. Many scientists are excellent communicators, to their peers. But this requires careful attention to detail and logical explanation, open acknowledgement of uncertainties, and dispassionate delivery. These qualities become liabilities when communicating to a non-scientific audience where entertainment, attention grabbing, 15 second sound bites, and self assuredness reign (e.g. Olson 2009). Here we report on a program initiated by NCAR and UCAR to develop new approaches to science communication and to equip present and future scientists with the requisite skills. If we start from a sound scientific finding with general scientific consensus, such as the warming of the planet by greenhouse gases, then the primary emphasis moves from the “science” to the “art” of communication. The art cannot have free reign, however, as there remains a strong requirement for objectivity, honesty, consistency, and above all a resistance to advocating particular policy positions. Targeting audience attitudes and beliefs, which studies such as the Six Americas research help identify, is key to effective science communications (e.g. Leiserowitz, Maibach, et al, 2009). We argue that the impact of the scientific message can be substantially improved by targeting it to these additional factors. This does require an understanding of the audience and a repackaging of the message to different societal groups. Logical and dispassionate presentation of evidence works for a target scientific audience, but major decisions from the policy to the personal level are influenced by many factors including immediacy, economics, culture, community leaders, emotional framing, and ideological filters.

  12. Etude et modlisation des proprits dynamiques des transistors MOS de puissance radio frquences (UHF)

    NASA Astrophysics Data System (ADS)

    Kassmi, K.; Rossel, P.; Tranduc, H.; Oms, F.

    1994-03-01

    Recent progress in the field of power MOSFET's aimed at fabricating devices whose performances in the power and frequency domains offer the opportunity of working in VHF and UHF bands. In telecommunications, the main application is the output stage (emission) in repeaters of mobile radiotelephony in the narrow bands of 890-915 MHz and 935-960 MHz, designed for the European system GSM (Global System for Mobile communications). In this paper, the main properties of the power MOSFET are analysed using an original physical model. This model is further simplified and embedded in the softwares SPICE and ELDO. Comparing the simulated and experimental static and small signal characteristics as well as the behaviour of resistive switching allows validation of our approach. Then, an UHF power MOSFET amplifier stage is analysed by considering a time domain methodology. Good agreement is found between experimental and simulated results on power gain, power output, large signal impedances and intermodulation distortion products. Les progrs effectus dans la technologie des transistors MOS de puissance permettent de raliser des composants dont les performances en frquence et en puissance offrent l'opportunit d'une utilisation en tant qu'amplificateur dans les bandes VHF et UHF. Dans le domaine des tlcommunications, une application potentielle est l'tage de sortiemissiondes rpteurs de radiotlphonie mobile dans les bandes troites 890-915 MHz et 935-960 MHz alloues au systme europen GSM (Groupe Spcial Mobile). Dans cet article, les proprits et caractristiques de ces composants sont analyses sur la base originale d'un modle physique gnral, puis d'un modle simplifi, compatible avec les logiciels SPICE et ELDO, du transistor VDMOS de puissance UHF. Des validations en rgime statique, rgime dynamique petit signal ainsi qu'en rgime de commutation rsistive sont tout d'abord prsentes. Enfin, une tude plus spcifique sur les proprits de ces transistors MOS en amplification de puissance radio frquences gain en puissance, puissance de sortie, impdances grands signaux, distorsion d'intermodulation d'ordre trois est effectue sur la base d'une mthodologie d'approche temporelle. Les comparaisons thorie exprience sont prsentes dans tous les rgimes de fonctionnement ; des commentaires quant aux performances actuelles de ces produits sont faits.

  13. Minimisation des inductances propres des condensateurs à film métallisé

    NASA Astrophysics Data System (ADS)

    Joubert, Ch.; Rojat, G.; Béroual, A.

    1995-07-01

    In this article, we examine the different factors responsible for the equivalent series inductance in metallized capacitors and we propose structures for capacitors that reduce this inductance. After recalling the structure of metallized capacitors we compare, by experimental measurements, the inductance due to the winding and that one added by the connections. The latter can become preponderant. In order to explain the experimental evolution of the winding impedance vs. frequency, we describe an analytical model which gives the current density in the winding and its impedance. This model enables us to determine the self resonant frequency for different types of capacitors. From where, we can infer the influence of the height of capacitors and their internal and external radius upon performances, It appears that to reduce the equivalent series inductance, it is better to use flat windings and annular windings. Dans cet article nous examinons les différents facteurs responsables de l'inductance équivalente série dans les condensateurs à film métallisé et proposons des géométries de condensateurs qui réduisent cette inductance. Après avoir rappelé la structure des condensateurs à film métallisé, nous comparons, par des mesures expérimentales, l'inductance due au bobinage et l'inductance ajoutée par les connexions. Cette dernière peut devenir prépondérante. Afin d'expliquer l'évolution de l'impédance du bobinage en fonction de la fréquence, nous décrivons un modèle analytique qui donne la densité du courant dans le bobinage et l'impédance de ce dernier. En outre, ce modèle permet de déterminer la fréquence de résonance série de divers types de condensateurs ce qui permet de déduire l'influence de la hauteur des condensateurs et de leurs rayons interne et externe sur les performances. Il apparaît ainsi que, pour diminuer l'inductance équivalente série, il vaut mieux employer des bobinages plats et des bobinages annulaires.

  14. Materials Science

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Materials Science Program is structured so that NASA s headquarters is responsible for the program content and selection, through the Enterprise Scientist, and MSFC provides for implementation of ground and flight programs with a Discipline Scientist and Discipline Manager. The Discipline Working Group of eminent scientists from outside of NASA acts in an advisory capacity and writes the Discipline Document from which the NRA content is derived. The program is reviewed approximately every three years by groups such as the Committee on Microgravity Research, the National Materials Advisory Board, and the OBPR Maximization and Prioritization (ReMaP) Task Force. The flight program has had as many as twenty-six principal investigators (PIs) in flight or flight definition stage, with the numbers of PIs in the future dependent on the results of the ReMaP Task Force and internal reviews. Each project has a NASA-appointed Project Scientist, considered a half-time job, who assists the PI in understanding and preparing for internal reviews such as the Science Concept Review and Requirements Definition Review. The Project Scientist also insures that the PI gets the maximum science support from MSFC, represents the PI to the MSFC community, and collaborates with the Project Manager to insure the project is well-supported and remains vital. Currently available flight equipment includes the Materials Science Research Rack (MSRR-1) and Microgravity Science Glovebox. Ground based projects fall into one or more of several categories. Intellectual Underpinning of Flight Program projects include theoretical studies backed by modeling and computer simulations; bring to maturity new research, often by young researchers, and may include preliminary short duration low gravity experiments in the KC-135 aircraft or drop tube; enable characterization of data sets from previous flights; and provide thermophysical property determinations to aid PIs. Radiation Shielding and preliminary In Situ Resource Utilization (ISRU) studies work towards future long duration missions. Biomaterials support materials issues affecting crew health. Nanostructured Materials are currently considered to be maturing new research, and Advanced Materials for Space Transportation has as yet no PIs. PIs are assigned a NASA Technical Monitor to maintain contact, a position considered to be a 5 percent per PI effort. Currently 33 PIs are supported on the 1996 NRA, which is about to expire, and 59 on the 1998 NRA. Two new NRAs, one for Radiation Shielding and one for Materials Science for Advanced Space Propulsion are due to be announced by the 2003 fiscal year. MSFC has a number of facilities supporting materials science. These include the Microgravity Development Laboratory/SD43; Electrostatic Levitator Facility; SCN Purification Facility; Electron Microscope/Microprobe Facility; Static and Rotating Magnetic Field Facility; X-Ray Diffraction Facility; and the Furnace Development Laboratory.

  15. Planning a Science Fair

    ERIC Educational Resources Information Center

    Ebert, Jim

    1976-01-01

    Presented are views, on planning science fairs and science fair projects, of a fair coordinator, a science teacher, and students. Also included are 25 questions which might result in science fair projects. (SL)

  16. Life sciences and environmental sciences

    SciTech Connect

    Not Available

    1992-02-01

    The DOE laboratories play a unique role in bringing multidisciplinary talents -- in biology, physics, chemistry, computer sciences, and engineering -- to bear on major problems in the life and environmental sciences. Specifically, the laboratories utilize these talents to fulfill OHER's mission of exploring and mitigating the health and environmental effects of energy use, and of developing health and medical applications of nuclear energy-related phenomena. At Lawrence Berkeley Laboratory (LBL) support of this mission is evident across the spectrum of OHER-sponsored research, especially in the broad areas of genomics, structural biology, basic cell and molecular biology, carcinogenesis, energy and environment, applications to biotechnology, and molecular, nuclear and radiation medicine. These research areas are briefly described.

  17. Life sciences and environmental sciences

    SciTech Connect

    Not Available

    1992-02-01

    The DOE laboratories play a unique role in bringing multidisciplinary talents -- in biology, physics, chemistry, computer sciences, and engineering -- to bear on major problems in the life and environmental sciences. Specifically, the laboratories utilize these talents to fulfill OHER`s mission of exploring and mitigating the health and environmental effects of energy use, and of developing health and medical applications of nuclear energy-related phenomena. At Lawrence Berkeley Laboratory (LBL) support of this mission is evident across the spectrum of OHER-sponsored research, especially in the broad areas of genomics, structural biology, basic cell and molecular biology, carcinogenesis, energy and environment, applications to biotechnology, and molecular, nuclear and radiation medicine. These research areas are briefly described.

  18. Do Gender-Science Stereotypes Predict Science Identification and Science Career Aspirations among Undergraduate Science Majors?

    ERIC Educational Resources Information Center

    Cundiff, Jessica L.; Vescio, Theresa K.; Loken, Eric; Lo, Lawrence

    2013-01-01

    The present research examined whether gender-science stereotypes were associated with science identification and, in turn, science career aspirations among women and men undergraduate science majors. More than 1,700 students enrolled in introductory science courses completed measures of gender-science stereotypes (implicit associations and

  19. Do Gender-Science Stereotypes Predict Science Identification and Science Career Aspirations among Undergraduate Science Majors?

    ERIC Educational Resources Information Center

    Cundiff, Jessica L.; Vescio, Theresa K.; Loken, Eric; Lo, Lawrence

    2013-01-01

    The present research examined whether gender-science stereotypes were associated with science identification and, in turn, science career aspirations among women and men undergraduate science majors. More than 1,700 students enrolled in introductory science courses completed measures of gender-science stereotypes (implicit associations and…

  20. Toward a Sustainable Science.

    ERIC Educational Resources Information Center

    Simonelli, Richard

    1994-01-01

    Addresses the importance of developing a "sustainable science" and the role that Indian science or "indigenous science" has in this development. Unlike Western science, Indian science acknowledges the important spiritual and emotional aspects of science. Discusses educational trends that stress the holism of knowledge and support a sustainable…

  1. Radio science

    NASA Astrophysics Data System (ADS)

    1984-10-01

    Radio science experiments use electromagnetic waves to probe or study the solar system. Three major research areas were identified within this discipline: radio astronomy, radar astronomy, and celestial mechanics. Radio astronomy (or radiometry) is the detection and measurement of naturally produced radio frequency emissions. Sources include surfaces, atmospheres, rings, and plasmas. Radar astronomy is the observation of man-made signals after their interaction with a target. Both imaging and non-imaging results. Celestial mechanics includes all studies related to the motions of (and gravity fields of) bodies within the solar system. These should not be considered rigid separations, but aid in the discussion of the data sets.

  2. Science toys

    NASA Astrophysics Data System (ADS)

    Crease, Robert P.

    2009-01-01

    "I have a low boredom threshold," Tim Rowett explains, ushering in my son Alex and me. Rowett is a jovial, professorishlooking man with wire-rimmed glasses and a short, white beard. Alex and I have gone to his flat in Twickenham, on the edge of London, to see his collection of fun stuff - jokes, games, puzzles and other toys related to science. When I ask what they have in common, Rowett has a ready, if not illuminating, answer: "They're just things that make people go 'Wow!'."

  3. Anbindung des SISIS-SunRise-Bibliothekssystems an das zentrale Identitätsmanagement

    NASA Astrophysics Data System (ADS)

    Ebner, Ralf; Pretz, Edwin

    Wir berichten über Konzepte und Implementierungen zur Datenprovisionierung aus den Personenverwaltungssystemen der Technischen Universität München (TUM) über das zentrale Metadirectory am Leibniz-Rechenzentrum (LRZ) in das SISIS-SunRise-Bibliothekssystem der Universitätsbibliothek der TUM (TUB). Es werden drei Implementierungsvarianten diskutiert, angefangen von der Generierung und Übertragung einfacher CSV-Dateien über ein OpenLDAP-basiertes Konzept als Backend für die SISIS-Datenbank bis zur endgültigen Implementierung mit dem OCLC IDM Connector.

  4. Discovering indigenous science: Implications for science education

    NASA Astrophysics Data System (ADS)

    Snively, Gloria; Corsiglia, John

    2001-01-01

    Indigenous science relates to both the science knowledge of long-resident, usually oral culture peoples, as well as the science knowledge of all peoples who as participants in culture are affected by the worldview and relativist interests of their home communities. This article explores aspects of multicultural science and pedagogy and describes a rich and well-documented branch of indigenous science known to biologists and ecologists as traditional ecological knowledge (TEK). Although TEK has been generally inaccessible, educators can now use a burgeoning science-based TEK literature that documents numerous examples of time-proven, ecologically relevant, and cost effective indigenous science. Disputes regarding the universality of the standard scientific account are of critical importance for science educators because the definition of science is a de facto gatekeeping device for determining what can be included in a school science curriculum and what cannot. When Western modern science (WMS) is defined as universal it does displace revelation-based knowledge (i.e., creation science); however, it also displaces pragmatic local indigenous knowledge that does not conform with formal aspects of the standard account. Thus, in most science classrooms around the globe, Western modern science has been taught at the expense of indigenous knowledge. However, because WMS has been implicated in many of the world's ecological disasters, and because the traditional wisdom component of TEK is particularly rich in time-tested approaches that foster sustainability and environmental integrity, it is possible that the universalist gatekeeper can be seen as increasingly problematic and even counter productive. This paper describes many examples from Canada and around the world of indigenous people's contributions to science, environmental understanding, and sustainability. The authors argue the view that Western or modern science is just one of many sciences that need to be addressed in the science classroom. We conclude by presenting instructional strategies that can help all science learners negotiate border crossings between Western modern science and indigenous science.

  5. Towards a Science of Science Teaching

    ERIC Educational Resources Information Center

    Yates, Carolyn

    2009-01-01

    This article is a contribution to the search for evidence-based models of learning to improve science education. The author believes that modern teachers should look to the sciences of cognitive psychology and neuroscience to build a science of science teaching. Understanding the relationships between learning and the brain's structure and

  6. Learning Science with Science Fiction Films.

    ERIC Educational Resources Information Center

    Cavanaugh, Terence; Cavanaugh, Catherine

    This paper is an excerpt from a book on learning science using science fiction. The focus is on the use of science fiction films to engage students and encourage greater enthusiasm and interest in science. "Jurassic Park" is used as an example that can provide educators with countless lesson opportunities. This approach recommends the use of fun…

  7. Science as Entertainment and Entertainment Science.

    ERIC Educational Resources Information Center

    Wassersug, Richard

    2002-01-01

    For many, doing science is entertaining, and engaging in a science activity for its entertainment value is a credible rationale. Drawing parallels between science and various forms of entertainment from sports to opera, highlights the value of "infotainment". Also mentions the risks associated with entertaining the public with science. (DLH)

  8. Towards a Science of Science Teaching

    ERIC Educational Resources Information Center

    Yates, Carolyn

    2009-01-01

    This article is a contribution to the search for evidence-based models of learning to improve science education. The author believes that modern teachers should look to the sciences of cognitive psychology and neuroscience to build a science of science teaching. Understanding the relationships between learning and the brain's structure and…

  9. Contextualized Science for Teaching Science and Technology.

    ERIC Educational Resources Information Center

    Koul, Ravinder

    A comprehensive view of science and technology in curricular reforms and materials is needed to promote public understanding and participation in science issues. This paper presents the results of an analysis of the treatment of the nature of science and technology in science curricular materials in India. Textbook sections on the conceptions of…

  10. Evaluation des connaissances des parents sur les bronchiolites aiguës

    PubMed Central

    Gueddari, Widad; Tazi, Abderrahmane; Ouardi, Amine; Nani, Samira; Zineddine, Abdelhadi

    2014-01-01

    Les infections respiratoires (IR) constituent la deuxième cause de mortalité infantile au Maroc, dû en partie à l'absence d'information et de sensibilisation. Le but de ce travail était d’évaluer les connaissances des parents sur la bronchiolite aiguë, infection respiratoire très fréquente. Nous avons réalisé une enquête basée sur un questionnaire, auprès de parents de nourrissons consultants pour toux, avec ou sans gêne respiratoire. 180 parents ont été inclus dans l’étude. Les parents pensaient que l'infection respiratoire était secondaire au climat froid (96%); seuls 4% ont évoqué une origine infectieuse. Aucun des parents ne savait que le lavage des mains était un moyen de prévention de la transmission. Les parents ont majoritairement répondu que la kinésithérapie respiratoire ne servait à rien (65%), et qu'elle était nocive (24.5%). Ce manque de connaissances fondamentales en matière d'IR et de bronchiolite en particulier, devrait inciter à entreprendre un programme de sensibilisation PMID:25328606

  11. Science kitsch and pop science: A reconnaissance.

    PubMed

    Kaeser, Eduard

    2013-07-01

    Science kitsch? The combination of these two words rings like an oxymoron. Science - as the common saying has it - exposes, discovers, tells the truth; kitsch conceals, covers, lies. I think, this "shadow" of science deserves a specific scrutiny, not only because it reflects the altered place and role of science in contemporary "knowledge" society but also because it pinpoints the task of relocating science in the "multicultural" context of postmodernism, with its different epistemic claims. The genre of science kitsch may help to regain credit by working as a probe to detect false pretensions, explanatory exuberance and exaggerations in science. PMID:23833170

  12. Science Advising

    NASA Astrophysics Data System (ADS)

    Tannenbaum, Benn

    2004-05-01

    The need for competent physical scientists in public policy is often overlooked. Science and technology play an ever-growing role in our lives, but the people setting the policies governing their use too often lack the skills and knowledge needed to make well-informed decisions. Making the transition from academia to public policy is not as difficult as one might imagine and can lead to a challenging, rewarding career. Dr. Tannenbaum recently completed a 2002-2003 AAAS Science and Technology Fellowship sponsored by the American Physical Society during which he worked in the office of U.S. Representative Edward J. Markey (D-MA) on nuclear nonproliferation issues. His work in Congressman Markey's office focused on issues including US nuclear weapons policy, missile defense, the nuclear program in Iran, prevention of the transfer of U.S. nuclear technology to North Korea, and the security of nuclear sites in Iraq. Dr. Tannenbaum will discuss this experience and observations concerning "underinformed and uninformed" decision-making in Congress and the role of scientists in that process. He will also discuss his current position at the Federation of American Scientists.

  13. Groundwater Science

    NASA Astrophysics Data System (ADS)

    McKenna, Sean A.

    A good introductory groundwater textbook must strike a delicate balance in presenting the basics of the physical, chemical, geological, mathematical, and engineering aspects of the groundwater field without being too lengthy or overly detailed. Charles Fitts states that his motivation for writing Groundwater Science was to be able to “…teach concepts and quantitative analyses with a clear, lean, but thorough book.” He has succeeded in striking this balance of having just the right amount of information, and has met his goals of producing a concise book that can be used to teach the concepts and analyses necessary for the study of groundwater.Overall, Groundwater Science would serve well as the text for an introductory groundwater course at the college senior or first-year graduate level. The author and the publisher have made excellent use of two-color, gray and blue-scale images throughout the book. The graphics are crisp and explanatory. Data sets needed to work some of the problems in the book are available as text files from its Web site (http://www.academicpress.com/groundwater). I found these files to be complete and easy to understand. The references are up to date and point the reader to additional information across a wide range of groundwater issues, and also provide a number of examples to illustrate different points made in the book.

  14. DES the year in review: controversies.

    PubMed

    Garg, S; Bourantas, C; Serruys, P W

    2013-04-01

    Drug-eluting stents (DES) have transformed interventional cardiology over the past decade. Whilst their efficacy has rarely been called into question, there have been concerns over the safety of the early devices, which has prompted the development of new coronary stents. Many of these new devices have entered clinical practice, however questions remain as to whether they offer the improvements in clinical outcomes that were originally anticipated. In addition, there is a debate whether the reported high efficacy of these devices enables percutaneous coronary intervention (PCI) to be performed in patient and lesion sub-groups previous entirely the domain of the cardiac surgeon. This review paper addresses these outstanding questions. PMID:23492595

  15. Organisation des gesundheitlichen Verbraucherschutzes auf Bundesebene

    NASA Astrophysics Data System (ADS)

    Tschiersky-Schöneburg, Helmut; Büttner, Antje

    Zahlreiche Krisen wie Dioxin belastete Futtermittel, die missbräuchliche Verwendung von Antibiotika in der Schweinemast und nicht zuletzt das Auftreten von BSE in Deutschland erschütterten Ende der neunziger Jahre das Vertrauen der Bürger in die Sicherheit der Lebensmittel. Mit dem Weißbuch zur Lebensmittelsicherheit, das im Januar 2000 herausgegeben wurde, hatte die Europäische Kommission ihre Erfahrungen aus dem BSE-Geschehen in ein neues Konzept für den Verbraucherschutz eingearbeitet. Kernstücke des Konzepts sind die ganzheitliche Betrachtung der Lebensmittelsicherheit von der landwirtschaftlichen Erzeugung bis zum Verzehr und der Anspruch nach Transparenz und Unabhängigkeit der Risikobewertung.

  16. Data Science: The Revolution in Science Education

    NASA Astrophysics Data System (ADS)

    Borne, K. D.

    2011-12-01

    I will describe the data science undergraduate and graduate programs at George Mason University, within the context of the ongoing revolution in data-intensive science. Both general and specific recommendations regarding science education will also be presented, extending from graduate training, to undergraduate science majors, and to undergraduate general education students. Examples of professional opportunities for data scientists in the key informatics (data science) research areas will be highlighted.

  17. Modélisation des boucles d'immunisation magnétique des navires

    NASA Astrophysics Data System (ADS)

    Le Dorze, F.; Bongiraud, J. P.; Coulomb, J. L.; Meunier, G.; Brunotte, X.

    1998-02-01

    This paper presents the problem of the three-dimensional modeling of degaussing coils in ships with a finite elements method. We show that these current coils are so close to the ferromagnetic sheets of the ship that they require a local very fine mesh which would be unrealistic for the whole complex structure of a real ship. We propose an alternative to the expensive mesh refinement called "reduced scalar potential jump”. The idea is to previously solve the local problem by another method and to use the result in the whole FEM modelling. We present the method of implementation in the FEM software FLUX3D and comparative results on a simple geometry. Cet article présente le problème de la modélisation en trois dimensions des boucles d'immunisation des navires par la méthode des éléments finis. Nous montrons que ces boucles de courant sont si proches des tôles ferromagnétiques du navire que leur modélisation requiert un maillage localement très fin, ce qui est irréaliste pour la structure complexe d'un navire réel. Nous proposons une alternative à ce coûteux affinage du maillage, appelée "saut de potentiel réduit”. L'idée est de résoudre au préalable le problème local par une autre méthode que les éléments finis et d'utiliser le résultat dans la modélisation globale. Nous présentons la méthode utilisée pour l'implantation de cette technique dans le logiciel d'éléments finis FLUX3D, et des résultats comparatifs sur une géométrie simple.

  18. Diffraction des neutrons : principe, dispositifs expérimentaux et applications

    NASA Astrophysics Data System (ADS)

    Muller, C.

    2003-02-01

    La diffraction de neutrons, sur monocristal ou sur échantillon polycristallin (ou poudre), est une technique très largement utilisée, en science des matériaux comme en biologie, lorsque l'on souhaite déterminer la structure cristalline d'un composé ou d'une molécule. Toutefois, le degré de précision de la détermination structurale est très corrélé au choix de l'instrument utilisé. Il s'en suit que la question “comment choisir l'instrument le mieux adapté au composé et à la problématique ?" apparaît comme fondamentale. L'objectif de ce cours est de tenter de répondre à cette question en décrivant brièvement les caractéristiques instrumentales de différents diffractomètres, en exposant les avantages spécifiques des expériences de diffraction de neutrons et en donnant quelques exemples d'application.

  19. Modeling nitrate-nitrogen load reduction strategies for the des moines river, iowa using SWAT

    USGS Publications Warehouse

    Schilling, K.E.; Wolter, C.F.

    2009-01-01

    The Des Moines River that drains a watershed of 16,175 km2 in portions of Iowa and Minnesota is impaired for nitrate-nitrogen (nitrate) due to concentrations that exceed regulatory limits for public water supplies. The Soil Water Assessment Tool (SWAT) model was used to model streamflow and nitrate loads and evaluate a suite of basin-wide changes and targeting configurations to potentially reduce nitrate loads in the river. The SWAT model comprised 173 subbasins and 2,516 hydrologic response units and included point and nonpoint nitrogen sources. The model was calibrated for an 11-year period and three basin-wide and four targeting strategies were evaluated. Results indicated that nonpoint sources accounted for 95% of the total nitrate export. Reduction in fertilizer applications from 170 to 50 kg/ha achieved the 38% reduction in nitrate loads, exceeding the 34% reduction required. In terms of targeting, the most efficient load reductions occurred when fertilizer applications were reduced in subbasins nearest the watershed outlet. The greatest load reduction for the area of land treated was associated with reducing loads from 55 subbasins with the highest nitrate loads, achieving a 14% reduction in nitrate loads achieved by reducing applications on 30% of the land area. SWAT model results provide much needed guidance on how to begin implementing load reduction strategies most efficiently in the Des Moines River watershed. ?? 2009 Springer Science+Business Media, LLC.

  20. OzDES multifibre spectroscopy for the Dark Energy Survey: first-year operation and results

    NASA Astrophysics Data System (ADS)

    Yuan, Fang; Lidman, C.; Davis, T. M.; Childress, M.; Abdalla, F. B.; Banerji, M.; Buckley-Geer, E.; Carnero Rosell, A.; Carollo, D.; Castander, F. J.; D'Andrea, C. B.; Diehl, H. T.; Cunha, C. E.; Foley, R. J.; Frieman, J.; Glazebrook, K.; Gschwend, J.; Hinton, S.; Jouvel, S.; Kessler, R.; Kim, A. G.; King, A. L.; Kuehn, K.; Kuhlmann, S.; Lewis, G. F.; Lin, H.; Martini, P.; McMahon, R. G.; Mould, J.; Nichol, R. C.; Norris, R. P.; O'Neill, C. R.; Ostrovski, F.; Papadopoulos, A.; Parkinson, D.; Reed, S.; Romer, A. K.; Rooney, P. J.; Rozo, E.; Rykoff, E. S.; Sako, M.; Scalzo, R.; Schmidt, B. P.; Scolnic, D.; Seymour, N.; Sharp, R.; Sobreira, F.; Sullivan, M.; Thomas, R. C.; Tucker, D.; Uddin, S. A.; Wechsler, R. H.; Wester, W.; Wilcox, H.; Zhang, B.; Abbott, T.; Allam, S.; Bauer, A. H.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Burke, D. L.; Carrasco Kind, M.; Covarrubias, R.; Crocce, M.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Doel, P.; Eifler, T. F.; Evrard, A. E.; Fausti Neto, A.; Flaugher, B.; Fosalba, P.; Gaztanaga, E.; Gerdes, D.; Gruen, D.; Gruendl, R. A.; Honscheid, K.; James, D.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Maia, M. A. G.; Makler, M.; Marshall, J.; Miller, C. J.; Miquel, R.; Ogando, R.; Plazas, A. A.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Walker, A. R.

    2015-09-01

    The Australian Dark Energy Survey (OzDES) is a five-year, 100-night, spectroscopic survey on the Anglo-Australian Telescope, whose primary aim is to measure redshifts of approximately 2500 Type Ia supernovae host galaxies over the redshift range 0.1 < z < 1.2, and derive reverberation-mapped black hole masses for approximately 500 active galactic nuclei and quasars over 0.3 < z < 4.5. This treasure trove of data forms a major part of the spectroscopic follow-up for the Dark Energy Survey for which we are also targeting cluster galaxies, radio galaxies, strong lenses, and unidentified transients, as well as measuring luminous red galaxies and emission line galaxies to help calibrate photometric redshifts. Here, we present an overview of the OzDES programme and our first-year results. Between 2012 December and 2013 December, we observed over 10 000 objects and measured more than 6 000 redshifts. Our strategy of retargeting faint objects across many observing runs has allowed us to measure redshifts for galaxies as faint as mr = 25 mag. We outline our target selection and observing strategy, quantify the redshift success rate for different types of targets, and discuss the implications for our main science goals. Finally, we highlight a few interesting objects as examples of the fortuitous yet not totally unexpected discoveries that can come from such a large spectroscopic survey.

  1. OzDES multifibre spectroscopy for the Dark Energy Survey: First-year operation and results

    SciTech Connect

    Yuan, Fang

    2015-07-29

    The Australian Dark Energy Survey (OzDES) is a five-year, 100-night, spectroscopic survey on the Anglo-Australian Telescope, whose primary aim is to measure redshifts of approximately 2500 Type Ia supernovae host galaxies over the redshift range 0.1 < z < 1.2, and derive reverberation-mapped black hole masses for approximately 500 active galactic nuclei and quasars over 0.3 < z < 4.5. This treasure trove of data forms a major part of the spectroscopic follow-up for the Dark Energy Survey for which we are also targeting cluster galaxies, radio galaxies, strong lenses, and unidentified transients, as well as measuring luminous red galaxies and emission line galaxies to help calibrate photometric redshifts. Here, we present an overview of the OzDES programme and our first-year results. Between 2012 December and 2013 December, we observed over 10 000 objects and measured more than 6 000 redshifts. Our strategy of retargeting faint objects across many observing runs has allowed us to measure redshifts for galaxies as faint as mr = 25 mag. We outline our target selection and observing strategy, quantify the redshift success rate for different types of targets, and discuss the implications for our main science goals. In conclusion, we highlight a few interesting objects as examples of the fortuitous yet not totally unexpected discoveries that can come from such a large spectroscopic survey.

  2. OzDES multifibre spectroscopy for the Dark Energy Survey: First-year operation and results

    DOE PAGESBeta

    Yuan, Fang

    2015-07-29

    The Australian Dark Energy Survey (OzDES) is a five-year, 100-night, spectroscopic survey on the Anglo-Australian Telescope, whose primary aim is to measure redshifts of approximately 2500 Type Ia supernovae host galaxies over the redshift range 0.1 < z < 1.2, and derive reverberation-mapped black hole masses for approximately 500 active galactic nuclei and quasars over 0.3 < z < 4.5. This treasure trove of data forms a major part of the spectroscopic follow-up for the Dark Energy Survey for which we are also targeting cluster galaxies, radio galaxies, strong lenses, and unidentified transients, as well as measuring luminous red galaxiesmore » and emission line galaxies to help calibrate photometric redshifts. Here, we present an overview of the OzDES programme and our first-year results. Between 2012 December and 2013 December, we observed over 10 000 objects and measured more than 6 000 redshifts. Our strategy of retargeting faint objects across many observing runs has allowed us to measure redshifts for galaxies as faint as mr = 25 mag. We outline our target selection and observing strategy, quantify the redshift success rate for different types of targets, and discuss the implications for our main science goals. In conclusion, we highlight a few interesting objects as examples of the fortuitous yet not totally unexpected discoveries that can come from such a large spectroscopic survey.« less

  3. Abondance et stratification verticale des elements dans l'atmosphere des etoiles mercure-manganese

    NASA Astrophysics Data System (ADS)

    Thiam, Mouhamadou

    Les étoiles mercure-manganèse appartiennent à la famille des étoiles chimiquement particulières. Elles présentent d'importants excès de mercure et de manganèse par rapport au soleil. Ces anomalies d'abondance sont généralement expliquées par la théorie de la diffusion atomique, jouant possiblementun rôle important au sein de leurs atmosphères. Cette thèse a pour but, dans un premier temps, de déterminer les abondances d'un grand nombre d'éléments (C, O, Mg, Si, P, S, Ca, Sc, Ti, Cr, Mn, Fe, Sr, Hg) peuplant l'atmosphère de quatre étoiles mercure-manganèse (HD 71066, HD 175640, HD 178065 et HD 221507). La seconde étape consiste à vérifier la présence d'une quelconque dépendance de l'abondance de ces éléments par rapport à la profondeur de formation des raies. Une variation de l'abondance par rapport à la profondeur, c'est-à-dire stratification, apporterait la preuve observationnelle de la présence de la diffusion atomique au sein de l'atmosphère de ces étoiles, ainsi que des contraintes servant à l'amélioration des modèles théoriques. Les spectres des étoiles étudiées sont obtenus à partir de l'archive de l'ESO- UVES. Les raies investiguées se situent à des longueurs d'onde plus grandes que celle du saut de Balmer oû le signal sur bruit, après normalisation, est supérieur à 300. Parmi les quatre étoiles investiguées, uniquement de la stratification du manganèse a été découverte dans l'atmosphère de l'étoile HD 178065. L'abondance du manganèse augmente significativement (environ 0.7 dex) sur l'intervalle t 5000 sondé entre -3.8 et -2.5. Ceci est la première détection de stratification du manganèse dans une étoile de type HgMn. Pour HD 175640, des indices de stratification du manganèse existent, mais l'étude d'autres spectres aiderait à confirmer ou non, la stratification de cet élément.

  4. FOREWORD Nanomaterials science Nanomaterials science

    NASA Astrophysics Data System (ADS)

    Rohrer, Heinrich

    2010-10-01

    The nanometer regime covers the transition from condensed matter behavior to atomic and molecular properties and thus is a very rich but also very demanding area in materials science. Close to the condensed matter side, properties and functions might still very well be scalable, whereas close to the atomic and molecular side, the scalability is mostly lost. Properties and functions change qualitatively or quantitatively by orders of magnitude when the dimensions become smaller than a critical size in the nanometer range. Examples are the ballistic regime for electron or spin transport at dimensions below the mean free path, near-field effects in scanning near-field optical microscopy and quantum wells when the dimensions are below an appropriate wavelength, novel electronic, mechanical, and chemical properties when the number of bulk atoms becomes smaller than that of surface atoms, quantum conduction, and Coulomb blockade. Thus, by going below a certain size, an abundance of novel properties and functions are at one's disposal, or, in other words, we can functionalize materials simply by reducing their size to the nanoscale. The key to the future lies in the functions that we give to materials, not just in finding 'novel functional materials'. This catch expression in many materials science programs and initiatives of the past two decades sounds great, but it is not what really counts. All materials are functional in one way or another and, therefore, all new materials are 'novel functional materials'. Certainly, finding new materials is always an important part of progress, but we should also focus on the much larger domain of novel functions that we can give to existing or modified materials. A good example is semiconductors: they are fifty or more years old and their properties are very well known, but they were not of widespread interest and use until the transistor changed their destiny into being the central material in the information technology revolution. Interfaces gave them their functions, and shaping them into ever-smaller functional components made them indispensably omnipresent as transistors—produced in billions per person and per year—and they are no doubt the rulers of today's technical world. The semiconductor and transistor serve as an inspiring example of functionalizing materials. The developments of microelectronics profited very much from scalability, that is, the properties and functions do not change significantly with size. Therefore, every step toward smaller dimensions was a technical and commercial challenge with risks well under control. The transition to the nanoscale, however, is discontinuous. Examples of this transition are the local probe methods that exploit the mechanically controlled proximity to the object under consideration and that have become indispensable as microscopes and as measuring and modifying tools, the size of molecular components that are much smaller than the smallest possibly achievable transistor, the properties and functions of materials below a critical size as mentioned above, the continuum properties versus discrete ones, and novel concepts inspired by living nature. Those novel concepts include growing circuits first and building the active components at the nodes afterwards and measuring weak by weak, small by small, and many by many. It is these discontinuous steps that make the nanoscale different, not just smaller. They pose exciting challenges, open great opportunities and nearly unlimited possibilities, but they also carry serious technical, commercial, environmental, and health risks. The nanoscale is also a great opportunity for materials science in general. Materials science is interdisciplinary per se. A materials scientist should have a reasonable understanding of physics, chemistry, engineering, and more recently, also biology. Certainly one can always team up with representatives from other disciplines and forge collaborations. However, an effective team can only emerge from a common understanding of the respective languages and problems. The lack of such an understanding is the Achilles' heel of so many collaborations. Despite the intrinsic interdisciplinary nature, materials science has split into various segments according to the type of material, for example, metals, organic, inorganic, biological, molecular, and so on. Each of them leads an independent life with little understanding for the others. This segmentation has made materials science lose, to an undesirable extent, its all-embracing mission for science and technology. There are laudable efforts to reunite different branches of materials science into comprehensive institutions; examples are NIMS in Tsukuba and IMR at Tohoku University, but institutions alone do not make the day. The nanoscale provides an excellent opportunity for scientists. The nanoscale was the bifurcation point where disciplines split and developed their own disciplinary views and language. This was the necessary core for the tremendous developments of science. Technology always had to rely on broader views. Now, disciplines merge again at the nanoscale, which will hopefully bring back to materials science much of what was lost over recent decades. It is difficult to delimit the nanodomain using general criteria since everything consists of atoms that are roughly a third of a nanometer in size, as is their distance from each other in condensed matter. In most cases, the individual addressabilities of nanostructures, properties, and processes are important. Atoms emerged from the anonymity as members of an ensemble; they have become our partners as individuals. As upper limits for nano, we might agree on 100-200 nm in object size and 1-10 nm in accuracy for local positioning, measuring, modifying, and controlling processes. The lower limit is open; a hundredth of a nanometer in positioning and measuring is nothing extraordinary. As a reviewer, I would accept a very interesting and daring research proposal, even if it interprets 'nano' somewhat too generously. After all, we want to promote top-class research and not average research just for the sake of 'nano'. Interfaces, material growth at given nano positions, shaping materials to a given nanosize and form, and bistability are key elements for functionalizing materials. InterfacesThe role of interfaces is rapidly increasing in science and technology. The number of interfaces increases with the square of the number of phases of materials. Even if the majority of them are impractical or useless, they are still much more abundant than the materials themselves, and they are the key to new functions. Think of the simple 'mechanical' interface responsible for the lotus effect where wetting is prevented by the rapidly changing surface curvature due to nanoparticles. Think of all the connections of a nanometer-sized area between very different materials, for example, for electron or spin transport. Think of the delicate interfaces that protect nanofunctional units from the environment but allow for communication of various types with other nanocomponents or with the macroscopic world. The solid-liquid interface plays a special role here. For me, it is the interface of the future, both for local growth and removal of nm3 quantities and for working with biological specimens requiring a liquid environment. Interfaces are the 'faces of action' and nanoscale materials science will be, to a great extent, 'interface science'. There is no need to change the name; attentive awareness suffices. Material growth at given nano positionsThis is the second central challenge in nanoscale materials science, but maybe still a futuristic one. We have heard much about the extraordinary properties of carbon nanotubes. They do a great job in certain applications, like tips of scanning tunneling and atomic force microscopes or nanoinjection needles or as bundles for electron emission or electron transport. As single carbon nanotubes of various lengths in complex micro- and nano-electronic circuits, however, they have to be grown at given positions, which is still problematic. Another example concerns the assembly scenario for electronics, components like sensors, actuators, and nano-systems. Macromolecular chemistry is producing highly functional macromolecules, but, eventually, they have to be produced and assembled at given positions. Shaping materials to a given nanosize and formIn the field of micro- and nanoelectronics, shaping semiconductors, many oxides, and selected metals down to 20-100 nm dimensions is standard. In nanomechanics, however, other materials might be more appropriate and better suited for a given task. In other cases, finishing procedures might be impossible or too time-consuming for large numbers of them. Components for counting electrons—more elegant and smaller than today's single-electron transistors—or adjustable holes for counting atoms and molecules will eventually be badly needed because of the 1/√N fluctuations in the properties and measurements at a small N, for example, N dopants in nanosize transistors or N electrons in very short current pulses. Bistable componentsBistable components, which do not require electrical currents, are aimed at reducing local energy dissipation and faster startup of personal computers. Magnetoresistive and ferroelectric random access memory (MRAMS and FRAMS) devices are the first attempts to use them in circuits. I am not aware of reported switching times that are considerably faster than a few nanoseconds, as required in today's storage. This is too slow for memory and much too slow for possible logic devices based on two-terminal bistable components. Bistable molecules, a mechanical switch, might be a valid and sufficiently fast alternative, certainly with all the challenges mentioned above. I have mentioned just a few obvious examples of the involvement of materials science in the new world of nanodimensions. However, for materials scientists, the sky is the limit. The thoughts given above are partly reflected in the lectures that I have recently given in Japan. It is my pleasure to thank my colleagues for the mutual understanding and hospitality that I always experience in Japan.

  5. Citizen Science

    NASA Technical Reports Server (NTRS)

    Memarsadeghi, Nargess

    2015-01-01

    Scientists and engineers constantly face new challenges, despite myriad advances in computing. More sets of data are collected today from earth and sky than there is time or resources available to carefully analyze them. Some problems either don't have fast algorithms to solve them or have solutions that must be found among millions of options, a situation akin to finding a needle in a haystack. But all hope is not lost: advances in technology and the Internet have empowered the general public to participate in the scientific process via individual computational resources and brain cognition, which isn't matched by any machine. Citizen scientists are volunteers who perform scientific work by making observations, collecting and disseminating data, making measurements, and analyzing or interpreting data without necessarily having any scientific training. In so doing, individuals from all over the world can contribute to science in ways that wouldn't have been otherwise possible.

  6. Les neuropathies liées au VIH/SIDA: une étude clinique chez les patients infectés par le VIH au Centre d'Excellence VIH/SIDA de l'Université de Lubumbashi

    PubMed Central

    Kabongo, Joe Katabwa; Kaputu-Kalala-Malu, Célestin; Luboya, Oscar; Mutombo, Valerien; Ntambwe, Abel; Mapatano, Mala Ali; Mukendi, Kavulu Mayamba

    2015-01-01

    Introduction En vue d'améliorer la prise en charge des patients souffrant de neuropathie (NP) associées à l'infection HIV, nous avons essayé de déterminer le profil clinique des personnes souffrant de NP au cours du suivi thérapeutique de leur infection HIV. Méthodes Il s'agit d'une étude transversale (n= 101) menée au centre d'excellence depuis 1 an. Notre analyse est essentiellement clinique. Par un examen clinique minutieux, nous avons recherché tous les symptômes et signes cliniques des NP. Subjectivement, les douleurs dominent le tableau. Pour affiner leur diagnostic, nous avons utilisé l’échelle DN4 (Diagnostic des douleurs neuropathiques) et l’échelle EVA (Evaluation de la gravité des douleurs). Nous avons ensuite analysé nos données en fonction de certains autres facteurs épidémiologiques tels que le taux des CD4, le traitement anti-HIV etc. Résultats Les 101 patients représentent 3,12% de la cohorte générale; 53,3% des patients présentent une abolition des réflexes ostéotendineux des membres inférieurs; 77,89% présentent une hypoesthésie thermo algique en chaussette et en gants; 25% ont présenté une amyotrophie des membres inférieurs; 76,5% ont été soumis à un traitement antirétroviral contenant la stavudine; 11,7% ont pris la didanosine (DDI) et Abacavir (ABC). 84% ont une moyenne de CD4 de 292 cel/mm3. Conclusion La NP altère la qualité de vie de nos patients et diminue l'adhérence au traitement antirétroviral. Plusieurs facteurs sont incriminés dans la survenue de la NP, l'effet direct des antirétroviraux, l'effet inflammatoire dysimmunitaire, l'effet infectieux lié aux infections opportunistes. D'autres facteurs seront recherchés et analysés ultérieurement. PMID:26185582

  7. Quantification des besoins en intrants antipaludiques: contribution à l'actualisation des hypothèses pour la quantification des intrants de prise en charge des cas de paludisme grave en République Démocratique du Congo

    PubMed Central

    Likwela, Joris Losimba; Otokoye, John Otshudiema

    2015-01-01

    Les formes graves de paludisme à Plasmodium falciparum sont une cause majeure de décès des enfants de moins de 5 ans en Afrique Sub-saharienne. Un traitement rapide dépend de la disponibilité de médicaments appropriés au niveau des points de prestation de service. La fréquence des ruptures de stock des commodités antipaludiques, en particuliers celles utilisées pour le paludisme grave, avait nécessité une mise à jour des hypothèses de quantification. Les données issues de la collecte de routine du PNLP de 2007 à 2012 ont été comparées à celles rapportés par d'autres pays africains et utilisées pour orienter les discussions au cours d'un atelier organisé par le PNLP et ses partenaires techniques et financiers afin de dégager un consensus national. La proportion des cas de paludisme rapportés comme grave en RDC est resté autour d'une médiane de 7% avec un domaine de variation de 6 à 9%. Hormis la proportion rapportée au Kenya (2%), les pays africains ont rapporté une proportion de cas grave variant entre 5 et 7%. Il apparaît que la proportion de 1% précédemment utilisée pour la quantification en RDC a été sous-estimée dans le contexte de la gestion des cas graves sur terrain. Un consensus s'est dégagé autour de la proportion de 5% étant entendu que des efforts de renforcement des capacités seraient déployés afin d'améliorer le diagnostic au niveau des points de prestation des services. PMID:26213595

  8. Learning sciences.

    PubMed

    Nathan, Mitchell J; Wagner Alibali, Martha

    2010-05-01

    The aims of the learning sciences (LS) are to understand the nature of learning from a broad range of perspectives, and to shape the ways that learning environments and resources are designed and used. LS incorporates both systemic and elemental approaches to investigating questions about learning, as a complement to the primarily elemental approach emphasized in cognitive science research. Thus, its greatest potential is in the integration of systemic and elemental perspectives. Four major themes are central. First, research in LS attempts to bridge the divide between research and practice. Second, research in LS is motivated by limitations of theories of learning and cognition for specifying instruction. Third, research in LS embraces the importance of analyzing and assessing complex interventions through both experimental and design-based research. Fourth, research in LS emphasizes the learning and behavior of the individual in interaction with the physical, social, and cultural world, as well as with semiotic and technical resources. Research in LS can be conceptualized along a continuum of time scales, from the more microscopic to the more macroscopic. The time-scale framework illustrates how disparate research traditions and research methods can function within a unifying framework for the study of learning and complex behavior. The effort to 'scale-up' from more elemental findings to more complex, authentic settings has been generative for LS, but faces serious challenges. There is an alternate route to establishing a cumulative scientific knowledge base, namely, 'scaling down' from more complex, ecologically valid levels to more elemental levels. Studies of basic learning processes, framed in the context of the larger system, are well positioned to support impact in authentic settings. Copyright 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website. PMID:26271374

  9. Science Overview

    NASA Technical Reports Server (NTRS)

    Bruning, Claus; Ko, Malcolm; Lee, David; Miake-Lye, Richard

    2006-01-01

    This report presents an overview of the latest scientific consensus understanding of the effect of aviation emissions on the atmosphere for both local air quality and climate change in order to provide a contextual framework for raising future questions to help assess the environmental benefits of technology goals. The questions may take the form of what are the environmental benefits that would result if goals are achieved, what are the consequences for other aviation pollutants, and whether tools exist to evaluate the trade-off. In addition to this documents, presentations will be made at the meeting to illustrate current developing views on these subjects. To facilitate studies on trade-offs among environmental impacts from aviation, one must start with scientific investigations that quantify the impacts. A second step is to select representative metrics with policy relevance so that diverse impacts can be put on the same common scale. The IPCC Special Report on Aviation (IPCC, 1999) serves as an excellent example of the first step. The report was produced by IPCC's Working Group 1, whose mandate is to provide the assessment of the scientific aspects of the climate system and climate change. An example of the second step is Witt et al. (2005), a study commissioned by the Environment DG of the European Commission. Within the context of CAEP, step 1 is aligned with the responsibilities of the Research Focal Points, while step 2 is more related to activities of FESG. These steps are likely to be iterative as proposed policy options will raise new science questions, and new science will expand or limit policy options. Past experiences show that clearly defined policy-related scientific needs will help focus the scientific community to marshal their intellects to provide the needed answers.

  10. Die Evolution des Universums. Eine Geschichte der Kosmologie.

    NASA Astrophysics Data System (ADS)

    Hiller, H.

    This volume covers in an elementary course a historical overview on cosmology ranging from the ancient aspects up to big bang theory and the concepts of inflationary universe and grand unified theories. Contents: 1. Auf dem Wege zur Wissenschaft. 2. Die neue Kosmologie. 3. Die Struktur des Weltalls. 4. Dramatik im Weltall. 5. Die endliche Welt. 6. Die Evolution des frühen Universums. 7. Die Zukunft. 8. Die neue Teleologie. 9. Das Leben.

  11. Fehlertoleranzanalyse des FlexRay Startup-Prozesses

    NASA Astrophysics Data System (ADS)

    Bnte, Sven; Milbredt, Paul

    Die PlexfiRay-Prozeduren Wakeup und Startup sollen eine konsistent-synchrone Kommunikation bezglich eines TDMA verwandten Verfuhrens herstellen. Beide Algorithmen werden in dieser Arbeit ubstrukt modelliert und mit Hilfe des Model Checkers SPIN bezglich Terminierung analysiert. Die Ergebnisse zeigen, dass in bestimmten Fehlerszenarios die Verwendung von Central Bus Guardians, die Clusterkonfiguration und das Verhalten des Hosts darber entscheiden, ob Fehlertoleranz und Laufzeitbeschrnkungen garantiert werden knnen.

  12. Mit Haken und Ösen: Die Physik des Kletterns

    NASA Astrophysics Data System (ADS)

    Czermin, Tina; Dullnig, Peter; Mathelitsch, Leopold; Schneider, Werner B.

    Beim Klettern mit dem Seil spielen zunächst die einfachen Gesetze des Flaschenzugs eine gravierende Rolle. Analysiert man die Gefahr eines Sturzes ins Seil, so spielt neben der Fallhöhe auch die Materialgröße der Seildehnung eine entscheidende Rolle. Bei der Sicherung des Kletterers haben sich in den vergangenen Jahren Friends bewährt. Sie greifen auch in Spalten, die sich nach außen leicht öffnen.

  13. What is science?

    USGS Publications Warehouse

    Shrake, D.L.; Elfner, L.E.; Hummon, W.; Janson, R.W.; Free, M.

    2006-01-01

    In 2000 The Ohio Academy of Science published its definition of "Science." Response to this definition led the Academy to produce a position paper entitled What is Science? The Academy officially adopted the position paper version of What is Science?, http: //www.ohiosci.org/ Whatisscience.pdf, at the April 2004 Ohio Academy of Science Annual Meeting. Response to this fact sheet demonstrated a need to further expand this document. Thus, this expanded version builds on the April 2004 position paper, What is Science? This paper clarifies what is science, the scientific method, a scientific hypothesis, a scientific theory, the importance of science, and what is not science.

  14. Science for Real Life

    ERIC Educational Resources Information Center

    Hammerman, Elizabeth

    2008-01-01

    State and national standards identify what students should know and be able to do, including what it means to "do" science, the historical significance of science achievement and its ethical underpinnings, and science from the human perspective. Middle level science programs that address the full range of science standards and connect learning to…

  15. Schools, Science and Society

    ERIC Educational Resources Information Center

    Andrew, Michael D.

    1970-01-01

    Discusses the importance of designing new science curriculum to emphasize these features: ecology-environment concepts; close tie between science and human values; technology and the application of science; processes which will enable man to more effectively use and control science and technology; integrated science; and…

  16. Science Education Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1983

    1983-01-01

    Papers presented include: (1) discussion in science lessons; (2) research on science interests of South Australian 12-year-olds (N=753); (3) chemistry and science philosophy; (4) methods/goals of teaching science to slow learners; (5) uses of industrial applications in science lessons; (6) nature of scientific observations; and (7) pros/cons of

  17. People behind the Science

    ERIC Educational Resources Information Center

    Kruse, Jerrid; Borzo, Sarah

    2010-01-01

    In addition to meeting National Science Education Standards (NSES) related to the history and nature of science (NOS), reading or hearing about real scientists helps students connect with science emotionally. The authors have even noticed increased student interest in science concepts during history of science discussions. Toward these efforts,…

  18. Science Education Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1983

    1983-01-01

    Papers presented include: (1) discussion in science lessons; (2) research on science interests of South Australian 12-year-olds (N=753); (3) chemistry and science philosophy; (4) methods/goals of teaching science to slow learners; (5) uses of industrial applications in science lessons; (6) nature of scientific observations; and (7) pros/cons of…

  19. Science Education Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1983

    1983-01-01

    Papers presented include: (1) CORE science--an exploratory study of pupils' perceptions of their science course; (2) chemistry and science philosophy; (3) taxonomy of scientific words (focusing on language of science, science words, theories of meaning, uses/implications of the taxonomy); and (4) description of experimental studies, a 16+ work…

  20. Salvaging Science Literacy

    ERIC Educational Resources Information Center

    Feinstein, Noah

    2011-01-01

    There is little evidence that the prevailing strategies of science education have an impact on the use and interpretation of science in daily life. Most science educators and science education researchers nonetheless believe that science education is intrinsically useful for students who do not go on to scientific or technical careers. This essay

  1. People behind the Science

    ERIC Educational Resources Information Center

    Kruse, Jerrid; Borzo, Sarah

    2010-01-01

    In addition to meeting National Science Education Standards (NSES) related to the history and nature of science (NOS), reading or hearing about real scientists helps students connect with science emotionally. The authors have even noticed increased student interest in science concepts during history of science discussions. Toward these efforts,

  2. Science for Real Life

    ERIC Educational Resources Information Center

    Hammerman, Elizabeth

    2008-01-01

    State and national standards identify what students should know and be able to do, including what it means to "do" science, the historical significance of science achievement and its ethical underpinnings, and science from the human perspective. Middle level science programs that address the full range of science standards and connect learning to

  3. Super Science Connections.

    ERIC Educational Resources Information Center

    Smith, Janice, Ed.

    This manual was developed to help K-3 teachers incorporate science and science activities as an integral part of their curricula. It integrates hands-on science activities with other curricular areas, particularly the language arts. The activities include science background information, science process skills, classroom management suggestions,…

  4. Salvaging Science Literacy

    ERIC Educational Resources Information Center

    Feinstein, Noah

    2011-01-01

    There is little evidence that the prevailing strategies of science education have an impact on the use and interpretation of science in daily life. Most science educators and science education researchers nonetheless believe that science education is intrinsically useful for students who do not go on to scientific or technical careers. This essay…

  5. Rôle des hyrates dans la formation de Titan et des satellites réguliers

    NASA Astrophysics Data System (ADS)

    Mousis, O.

    2001-12-01

    Cette these est dediee a l'etude de l'origine de Titan et de son atmosphere. Dans l'hypothese ou la subnebuleuse de Saturne etait geometriquement mince, le modele de disque turbulent utilise, derive des travaux de Dubrulle (1993), est moins dense que le modele de Prinn et Fegley (1981). De ce fait, les conversions de Co en CH4 et de N2 en NH3 ont ete inhibees dans la subnebuleuse, contrairement a ce qui est couramment admis pour interpreter la presence du methane dans l'atmosphere de Titan. C'est pourquoi nous avons developpe un nouveau scenario de la formation de titan, qui tient compte simultanement des contraintes resultant de la chimie de la subnebuleuse et des abondances de CH4, N2 et CH3D mesurees dans l'atmosphere du satellite. Nous faisons l'hypothese que ces gaz proviennent initialement de la vaporisation du nuage presolaire, qui s'effondra et forma le Soleil et son disque environnant. Lors du refroidissement de la nebuleuse, les volatils auraient ete pieges sous formes de clathrates d'hydrates dans les grains, puis dans les planetesimaux qu'ils formerent. Les planetesimaux hydrates a l'origine de la formation de Titan seraient alors des rescapes de l'effondrement hydsrodynamique de la feeding zone de Saturne. Ce scenario a ete applique aux subnebuleuses de Jupiter et d'Uranus, et a apporte un certain nombre de contraintes sur la formation des satellites reguliers de ces planetes. Le temps et la zone de formation des grains cometaires ont egalement ete estimes dans la nebuleuse solaire. Enfin, l'etude experimentale de la temperature de fusion du dihydrate d'ammoniac dans la gamme des hautes pressions a apporte des nouvelles donnees thermodynamiques qui permettront d'ameliorer les modeles de l'interieur de Titan.

  6. Team science for science communication

    PubMed Central

    Wong-Parodi, Gabrielle; Strauss, Benjamin H.

    2014-01-01

    Natural scientists from Climate Central and social scientists from Carnegie Mellon University collaborated to develop science communications aimed at presenting personalized coastal flood risk information to the public. We encountered four main challenges: agreeing on goals; balancing complexity and simplicity; relying on data, not intuition; and negotiating external pressures. Each challenge demanded its own approach. We navigated agreement on goals through intensive internal communication early on in the project. We balanced complexity and simplicity through evaluation of communication materials for user understanding and scientific content. Early user test results that overturned some of our intuitions strengthened our commitment to testing communication elements whenever possible. Finally, we did our best to negotiate external pressures through regular internal communication and willingness to compromise. PMID:25225381

  7. Mecanique et mecanisme de la dechirure des materiaux textiles

    NASA Astrophysics Data System (ADS)

    Triki, Ennouri

    Cette thèse vise à apporter une contribution à l’étude et à la modélisation de la déchirure des textiles et des textiles enduits. Notons que la résistance à la déchirure est l’une des caractéristiques mesurées pour les équipements de protection contre les agresseurs mécaniques en milieu de travail. Jusqu'à présent, ce comportement en déchirure a été étudié en mesurant la force de déchirure et le travail de déchirure. De fait, aucun critère de rupture en déchirure n’existe actuellement. Par conséquent, en s’inspirant de la théorie du Griffith et de la mécanique de la rupture, une formulation d’un nouveau critère de rupture des structures textiles a été proposée. Cette approche offre la possibilité de déterminer d’une manière plus précise l’énergie nécessaire pour la création d’une nouvelle surface de rupture. Ce critère nous permet d’analyser l’effet des caractéristiques des tissus sur la variation de l’énergie de rupture. Cette étude montre que la résistance au glissement des fils dans la structure est le principal facteur qui contrôle la propagation de la fissure. En se basant sur la théorie de la mécanique de la rupture, un modèle de calcul de l’énergie de rupture par déchirure a été aussi élaboré. Ce modèle de déchirure relie l’énergie aux paramètres caractérisant les phénomènes affectant la déchirure des tissus, notamment la force de glissement et la force à la rupture des fils. Cette modélisation a tenu compte de certaines caractéristiques des tissus tels que l’épaisseur du matériau, la densité des fils, etc. Par l’étude de la variation de l’énergie de rupture par déchirure en fonction du rapport établi entre la force à la rupture et la force de glissement d’un fil ( FYB/FS), l’effet des mécanismes de la propagation de la fissure dans les tissus sur leur comportement en déchirure a été aussi observé. Les résultats obtenus permettent de distinguer deux différentes catégories de déchirure. Pour les basses densités des fils, la fissure se propage dans le tissu par glissement des fils, alors que pour les hautes densités des fils, la déchirure est obtenue par la rupture des fils. Ainsi, il est important de noter que l’énergie de rupture par déchirure des tissus est maximale lorsque le rapport FYB/FS est proche de l’unité. En ce qui a trait à la déchirure des textiles enduits, la propagation de la fissure est obtenue par déchirure du support textile et de l’enduit de manière simultanée ainsi que par le délaminage du système textile-enduit. La définition d’un critère de rupture pour les textiles enduits nous a permis de constater que l’enduction d’un support textile par une couche d’élastomère engendre une diminution de son énergie de rupture. En outre, l’étude de la déchirure du support textile, de l’enduit et des textiles enduits a montré que l’énergie obtenue pour la couche de l’enduit est très faible si nous la comparons avec celles du support textile et du textile enduit. L’étude de l’effet du vieillissement sur l’énergie de rupture par déchirure a aussi fait l’objet de cette thèse. L’exposition des textiles enduits à différentes températures de vieillissement montre que le comportement en déchirure des textiles et des textiles enduits est similaire pour les durées les plus faibles. Par contre, une accélération de la réduction de la résistance à la déchirure est observée pour les textiles enduits aux temps de vieillissement plus élevés. Ce phénomène peut éventuellement être attribué à une augmentation de l’adhésion du système textile-enduit suite au traitement de vieillissement. La diminution de la mobilité des fils ainsi engendrée cause alors une importante chute de la valeur de l’énergie de rupture par déchirure. Mots clés : Textiles, Textiles enduits, Énergie de rupture, Modélisation, Vieillissement thermique.

  8. NARRATIVE: A short history of my life in science A short history of my life in science

    NASA Astrophysics Data System (ADS)

    Manson, Joseph R.

    2010-08-01

    I was certainly surprised, and felt extremely honored, when Salvador Miret-Artés suggested that he would like to organize this festschrift. Before that day I never anticipated that such an honor would come to me. I would like to thank Salvador for the large amount of time and work he has expended in organizing this special issue, the Editors of Journal of Physics: Condensed Matter for making it possible, and also the contributing authors for their efforts. My family home was outside of Petersburg, Virginia in Dinwiddie County in an area that was, during my youth, largely occupied by small farms. This is a region rich in American history and our earliest ancestors on both sides of the family settled in this area, beginning in the decade after the first Virginia settlement in Jamestown. My father was an engineer and my mother was a former school teacher, and their parents were small business owners. From earliest memories I recall being interested in finding out how things worked and especially learning about the wonders of nature. These interests were fostered by my parents who encouraged such investigations during long walks, visits to friends and relatives, and trips to museums. However, my earliest memory of wanting to become a scientist is associated with a Christmas gift of a chemistry set when I was about ten years old. I was absolutely fascinated by the amazing results that could be achieved with simple chemical reactions and realized then that I wanted to do something in life that would be associated with science. The gift of that small chemistry set developed over the next few years into a serious interest in chemistry, and throughout my junior high-school years I spent nearly all the money I earned doing odd jobs for neighbors on small laboratory equipment and chemical supplies, eventually taking over our old abandoned chicken house and turning it into a small chemistry lab. I remember being somewhat frustrated at the limits, mainly financial, that kept the scale of my chemical experiments to simple things such as growing crystals of all available salts, making interesting colors and dyes, and a whole variety of pyrotechnics. The fireworks and small explosives were largely carried out without the knowledge of my parents, and it was surely fortunate that my lab was well away from the house because fires nearly got out of hand a couple of times. Interest in becoming a chemist continued into my high-school years until I took a traditional course in elementary physics. This course was a little out of the ordinary because it was taught by the industrial shop teacher, Mr John M Leete, a man who had an interest in science but very little scientific training or knowledge. He had been given this course because there was nobody else available to teach it, and the way he chose to handle his assignment was to gather the eight or so students around a circular table and spend each hour of class time reading a book together and trying to understand it. This turned out to be an interesting and effective way to learn, with Mr Leete probably learning just as much as the students. The experience of this course made quite an impression, not only because of the fascination of the subject matter, but also because of what it demonstrated about the process of teaching and learning. It was at this time that I realized that physics was the science that I wanted to pursue. I finished high-school at the beginning of 1961, and after working in a local tobacco factory for a short period I enrolled as an undergraduate at the University of Richmond, a college with a very beautiful campus on the outskirts of Richmond and relatively close to home in Petersburg. Another advantage of living in Richmond was that I could continue playing in the Richmond Symphony Orchestra, eventually becoming its principal bassoonist. Music was an interest that developed in high school, which was when I first became a member of the Richmond Symphony, and later in college I earned a modest income playing there as well as in the Norfolk Symphony and several other ensembles. After four years in Richmond and graduating with a degree in physics and mathematics I enrolled as a graduate student in the Physics Department of the University of Virginia. At Virginia I went to work with the well-known Professor Nicholas Cabrera who was then also the department Chair. After a little more than a year, Cabrera took a temporary leave of absence to take a position in Mexico, but this temporary departure later became permanent when he answered a call to return to Spain to establish and lead the Department of Physics at the new Universidad Autonoma de Madrid. Before leaving Virginia, however, Cabrera hired a new Assistant Professor who had already made quite a name for himself, and this was Vittorio Celli. Celli and I immediately hit it off and I continued my studies with him. He is the person to whom I owe the greatest debt as a teacher and mentor who instilled the highest standards of scientific research. We began work on some problems in superconductivity and surface magnetism which I found very interesting, but one day we had a meeting with Professor Sam Fisher of the Department of Aeronautical Engineering at Virginia that totally changed the direction of our research. Sam and his graduate students had carried out a series of experiments on the scattering of high-quality jet beams of helium atoms off of clean, cleaved lithium fluoride surfaces under high-vacuum conditions. Essentially, Sam was repeating experiments originally performed by Otto Stern and coworkers in Frankfurt and Hamburg in the late 1920s, but he had not realized the fact that he was seeing diffraction patterns. We immediately recognized that he was measuring diffraction, and not long thereafter we recognized that his measurements should be sufficiently precise to measure energy transfers due to single quantum excitations of vibrations at the surface. Both Vittorio and I quickly dropped the research that we had been doing and started to think about developing theories that could exploit the possibilities of gaining information about the microscopic structure and dynamics of surfaces using, as a tool, the methods of atom scattering. With Cabrera and Frank Goodman, who was Guest Professor in the Aeronautical Engineering Department, we developed these ideas into theories that have turned out to be useful for describing both diffraction and single-phonon inelastic scattering in atom-surface collisions. This experience of developing theoretical explanations for that interesting new data of Fisher's group left me with a great appreciation for experimental physics and is probably the reason that a large part of my work ever since has been oriented toward trying to develop theoretical methods to aid in explaining experimental results. A major change in life, and one very much for the better, occurred during my graduate school years, and this was marriage to Lucy Schenkman. We met through our mutual interest in music when I was an undergraduate in Richmond. Our marriage has been a very rewarding experience. We are extremely proud of our two children, who have now gone on into their marriages and careers, and have given us four wonderful grandchildren. After receiving my PhD in 1969 I took a position as Assistant Professor of Physics at Clemson University and have remained there ever since. During those early years at Clemson our teaching loads were rather high, but there was still time to carry out a research program and mentor graduate students. Clemson had established a generous sabbatical program and in 1977 I took my first sabbatical at the Centre d'Études Nucléaires de Saclay (now Le Centre CEA de Saclay), working with Jean Lapujoulade and Georges Armand. Armand by that time was doing work in various areas of the theory of surface physics and Lapujoulade was leader of a group that had built one of the earliest pieces of apparatus for scattering jet beams of helium atoms from surfaces under clean high-vacuum conditions. This sabbatical was the beginning of a very fruitful and extremely pleasant collaboration working on a large variety of problems on the structure and dynamics of metal surfaces as elucidated by helium atom scattering, a collaboration that lasted until the retirements of Armand and Lapujoulade in the early 1990s. Nearly every summer and two additional sabbaticals in 1984 and 1992 were spent in this very stimulating research atmosphere located in the scientific complex on the southern edge of Paris. This period included collaborations and interactions with many of the colleagues, visitors and students at Saclay including C S Jayanthi, Abdelkader Kara, Luc Barbier, Hans-Joachim Ernst, Francoise Fabre and Bernard Salanon. Directly after this first sabbatical I spent a summer under the auspices of an Oak Ridge Associated Universities grant working with Rufus Ritchie in what was then the Health Sciences Division of the Oak Ridge National Laboratory (ORNL). Ritchie was a senior scientist at ORNL as well as a professor at the Physics Department of the University of Tennessee at nearby Knoxville. This one summer at ORNL also developed into a long and productive, as well as extremely pleasant, scientific collaboration with Ritchie that lasted into the 1990s. During the academic years at Clemson I was able to take off to ORNL for week-long periods several times a year. Our work involved calculating energy transfers in the interactions of electrons and other charged particles with surfaces, problems involving interactions of atomic and charged particles with surface plasmons and theories for developing interaction potentials between particles or between particles and surfaces. This work also had the great advantage of developing interactions and scientific collaborations with many others at ORNL, including Thomas Ferrell and Bruce Warmack. One of the advantages of being a scientist is the opportunity to travel and meet colleagues and people from all over the world. Sometimes the importance of the social aspects of science is not recognized, but they play an important role both in the satisfaction of being a scientist and also in shaping the problems and research topics that a given scientist works on, and sometimes in unexpected ways. As an example, these first visits to Paris and Oak Ridge brought me into contact with many scientists, several of which I would eventually collaborate with throughout my career. Among these were Salvador Miret-Artés and Pedro Echenique. In the early 1980s, during one of my summer visits to Saclay, it was Jean Lapujoulade who brought me a preprint of a manuscript by Salvador Miret-Artés, and asked me to look at it to see if it made any sense. Indeed, the ideas in that paper did make sense. In fact, Miret-Artés had pointed out a very special type of resonance effect that should be readily observable in He atom scattering from corrugated surfaces, an effect that was obvious when one thought about it a little, but that nobody up to then had ever noticed. This paper eventually led to a visit by Miret-Artés to Saclay where we met, and over the years this meeting developed into a friendship and a long and valuable collaboration that continues to this day. My collaboration with Pedro Echenique was initiated through contact with Rufus Ritchie. From the beginning Ritchie would often mention the name of this very energetic and brilliant Basque with whom he worked while he was on sabbatical at the University of Cambridge in England and with whom he had a continuing collaboration. Furthermore, several of the problems the two of us worked on were ones that Ritchie had also discussed with Echenique. The collaboration between Echenique and Ritchie continued to be prolific, and within a few years of that initial ORNL visit I was also collaborating with Echenique, and that collaboration continues. Beginning the summer of 1985 I began a collaboration with Professor J Peter Toennies of the Max-Planck-Institut für Strömungsforschung in Göttingen, Germany (now the Max-Planck-Institut für Dynamik und Selbstorganization). Toennies was already, at that time, a major figure in the areas of physics and chemistry that use molecular and atomic beams. This was just a few years after he, with graduate student Bruce Doak, had succeeded in the first measurements of surface specific phonons using He atom scattering and, in particular, had obtained complete dispersion relations for Rayleigh modes. This was precisely the type of experiment that Celli, Cabrera and I had suggested over a decade earlier, so our research interests were an excellent match. Our work that summer with graduate student Christof Wöll and postdoc Angela Lahee developed experimental and theoretical methods for measuring the presence of isolated atomic or molecular adsorbates on surfaces. This initial visit led to a long and productive period of research on many aspects of He atom scattering from surfaces, and almost every summer from then through 1997 was spent in the very pleasant and historic city of Göttingen, which still has visible roman ruins and many old German buildings dating from the 1500s. This period was marked by interactions and collaborations with many of the graduate students, postdocs and visitors to the Toennies lab. Many of these collaborations continue to some extent even today, and include work with Andrew Graham, John Ellis, Frank Hofmann, Massimo Bertino, Robert Grisenti, Alexi Glebov, Wieland Schöllkopf, Walter Silvestri and Horst-Günter Rubahn. It was also during this period that I developed a long friendship and scientific collaboration with Jim Skofronick and Sanford Safron of the Department of Physics at Florida State University. Both were frequent visitors to the Toennies laboratory, and our collaboration extended far beyond our overlapping stays there. Among the fondest memories of visits to Göttingen are the many long walks and bicycle rides taken with these colleagues and many others through the streets of Göttingen and the surrounding countryside of Niedersachsen. The long series of visits to Göttingen were interrupted by three summers beginning in 1988 at the Institut für Grenzflachenforschung and Vakuumphysik at the Forschungszentrum Jülich in Germany working with George Comsa and his group. I had met Comsa in the late 1970s at a scientific meeting in France and we had continued our scientific correspondence ever since, which eventually led to the invitation to visit his lab for an extended stay. Among the very large range of surface-related experiments being carried out in the Comsa group were machines, operated by Bene Poelsema and Rudolf David and the then graduate students Klaus Kern and Peter Zeppenfeld, devoted to He atom scattering from metal and adsorbate-covered surfaces. Once again, it was a great privilege to carry out scientific research in such a stimulating environment. In 1998, with a three-month summer visit, I began a collaboration with Professor Karl-Heinz Rieder at the Institut für Experimentalphysik of the Freie Universität Berlin in Germany. Rieder was a pioneer in the field of surface scattering experiments using helium and other rare gas atomic beams as projectiles and after he moved to the Freie Universität from the IBM Zürich laboratories he continued this work as well as becoming a world leader in the field of single molecule manipulation on surfaces using scanning tunneling microscopy (STM). This collaboration resulted in visits to Berlin every summer through 2006 during which we collaborated on several projects involving both atom-surface scattering and STM. The work during this period included interesting collaborative work with many members of the Rieder group including Ludwig Bartels, Daniel Farías, Gerhard Meyer and Saw Hla. It was a great experience to be able to pursue science in such favorable surroundings, and to have, in addition, all the cultural advantages of the city of Berlin with its concerts, opera and museums. Although I have been fortunate to be able to take my family to live in many beautiful and interesting places such as Göttingen, Jülich and Berlin, it has always been Paris and France that we remembered with the greatest fondness, probably because it was the first of our travel ventures and because our children were very young when we first went and they did a large part of their growing up there. So it was a real pleasure to have the opportunity to return to Paris for an extended summer visit in 2007, this time not at Saclay, but at the Université de Paris-Sud in its Laboratoire des Collisions Atomiques et Moléculaires (LCAM). Several times in the preceding years I had discussed and corresponded with Hocine Khemliche of that laboratory about their experiments on the scattering of ions and neutral atoms and molecules from surfaces. They had just published a paper that had attracted considerable attention on the diffraction of very fast atoms from the corrugated surface of lithium fluoride, and our discussions eventually led to an invitation to come and work with him and his colleague, Philippe Roncin. It was a real pleasure for my wife and I to return to the Paris area and to re-experience some of the things that we had done there two decades earlier, to observe the changes in culture and lifestyles that had occurred since, and to experience a whole new set of adventures. The following summer of 2008 I was Guest Professor at the Donostia International Physics Center in San Sebastian, Spain. This institute was created and is directed by Pedro Echenique and it was a great honor to be able to work in that environment and enjoy the company and discussions with all the prominent scientists there, the many guests as well as the permanent staff. In the spring and summer of 2009 I was Guest Professor in the Institut für Experimentalphysik of the Technische Universität Graz in Austria, the institute directed by Professor Wolfgang Ernst. The story of how this particular collaboration developed is interesting because it illustrates again how important personal contacts and social interactions are in the progress of science. In 2007 I was contacted by Bodil Holst, then of the TU-Graz and now at the Technical University of Bergen in Norway, about the possibility of having one of her very bright graduate students visit Clemson for a few months as a part of his work in analyzing some He atom scattering data that they had taken on silica glass surfaces. A decade earlier Holst had been a postdoctoral research associate at the Toennies laboratory in Göttingen during several of the summers I was also there and, although we never worked directly together at that time, we had many interesting discussions about science and other subjects. The student, Wolfram Steurer, arrived in Clemson in the middle of the fall semester with his belongings in a bag that was smaller than the guitar he carried strapped over his back. He immediately created for himself a place in our department, and by the time he left three months later we had developed some rudimentary ideas of how to analyze the data he had, and we also suspected that this data might reveal some new aspects of the dynamics of glass surfaces that had not been realized before. Wolfram delved into this problem with a vengeance, and shortly afterwards we began a series of papers involving Holst, Ernst and Steurer and the Graz graduate students, Andreas Apfolter and Mattias Koch, as well as Elin Søndergård of the French CNRS laboratory located at the St Gobain Corporation's research facilities in Paris. It was this initial contact with Holst a decade earlier that eventually led to a productive period of research on glass surfaces, something that I would have never predicted beforehand, but a collaboration that shows every sign of continuing into the future to produce new and interesting results. So, this brings the history of my career in science nearly to the present. In 2008 I decided, after several years of contemplation, to retire from official service at Clemson and become an emeritus faculty member. However, I am still actively continuing research, retain an office in the department, keep regular contact with my university peers, and remain active in promoting and mentoring the careers of some of my colleagues. Above all, however, I remain active in many of the collaborations that I have developed over the years, some of which are described here. As this brief story should indicate, I have enjoyed a very rich life in science, and much of this enjoyment is due to the people I have been associated with. One could not have asked for a finer group of friends, colleagues, students and collaborators, and I fully anticipate that my association with them and my contributions to science will continue into the foreseeable future.

  9. Reconnaissance optique des formes en parallele utilisant des reseaux de neurones et une mire de reduction de dimensions

    NASA Astrophysics Data System (ADS)

    Gagne, Philippe

    Cette recherche vise à la mise en OEuvre optique de la reconnaissance des images en utilisant une mire d'anneaux afin de générer des vecteurs caractéristiques qui seront ensuite classifiés par un réseau de neurones. On proposera deux architectures originales: une qui permettra la reconnaissance invariante sous rotation en utilisant un corrélateur conjoint; l'autre montage permettra une classification en parallèle de plusieurs images grâce à la capacité des mires d'anneaux de compresser l'information. Ce dernier montage est basé sur un corrélateur 4F. On présentera des résultats optiques expérimentaux pour ces deux montages. Pour arriver à des résultats concluants on analysera le comportement des vecteurs obtenus à partir d'une mire d'anneaux, on introduira une règle d'apprentissage optimisant le pic de corrélation en réduisant les pics parasites et on corrigera à l'aide d'un algorithme génétique les modulations de phases générées par le modulateur spatial à cristaux liquides.

  10. Les sarcomes des tissus mous: à propos de 33 cas

    PubMed Central

    Abdou, Jiddou; Elkabous, Mustapha; M'rabti, Hind; Errihani, Hassan

    2015-01-01

    L'objectif de cette étude est de rapporter les particularités épidémiologiques, cliniques, histologiques, thérapeutiques et évolutives des sarcomes des tissus mous à l'Institut National d'Oncologie et de définir les facteurs influençant la survie des patients. C'est une étude rétrospective de 33 cas de sarcome des tissus mous, colligés entre janvier 2008 et décembre 2010. Les critères d’éligibilité étaient un âge supérieur à 16 ans, une épreuve histologique d'un sarcome des tissus mous à l'exclusion des tumeurs stromales gastro-intestinales (GIST). Les items recueillis étaient: épidémiologiques, cliniques, histologiques, Radiologiques, et thérapeutiques. Des analyses univariées puis multivariées ont été réalisées à la recherche de facteurs influençant la survie à 2 ans. Il s'agit de 33 cas, 17 Hommes et 16 Femmes, l’âge moyen était de 43,21 ans (Extrêmes= 18-76 ans). La tumeur était localisée aux extrémités dans 24 cas (72,72%). Le type histologique prédominant était le Liposarcome dans 9 cas (27,27%). Le stade tumoral était localisé dans 25 cas (75,8%), métastatique dans 8 cas (24,2%). Vingt-cinq tumeurs ont été traitées chirurgicalement dont 21 cas (84%) de chirurgie conservatrice et 4 cas (16%) de chirurgie radicale. La radiothérapie a été réalisée chez 10 patients (30,3%). La chimiothérapie a été faite chez 20 patients. En analyse univariée les facteurs pronostiques étaient l’âge (p=0,03) et le stade tumoral (p=0,09). L’âge et le stade tumoral sont des facteurs pronostiques influençant la survie des sarcomes des tissus mous. PMID:27022434

  11. Nouvelle approche à la prise en charge des condylomes

    PubMed Central

    Lopaschuk, Catharine C.

    2013-01-01

    Résumé Objectif Faire le résumé des anciens et des nouveaux moyens de traitement des verrues génitales ou condylomes et déterminer comment les utiliser de manière appropriée. Sources des données Une recherche documentaire a été effectuée dans les bases de données suivantes: MEDLINE, PubMed, EMBASE, base de données des synthèses systématiques et registre central des études contrôlées de la Collaboration Cochrane (en anglais), ACP Journal Club et Trip. Les bibliographies des articles extraits ont aussi été examinées. Les études cliniques, les articles de révision qualitative, les rapports consensuels et les guides de pratique clinique ont été retenus. Message principal Les verrues symptomatiques sont présentes chez au moins 1 % des personnes âgées entre 15 et 49 ans et on estime que jusqu’à 50 % des gens sont infectés par le virus du papillome humain à un moment donné de leur vie. L’imiquimod et la podophyllotoxine sont 2 nouveaux traitements pour les verrues génitales externes qui sont moins douloureux et peuvent être appliqués par les patients à la maison. De plus, il a été démontré que le vaccin quadrivalent contre le virus du papillome humain est efficace pour prévenir les condylomes et le cancer du col. Les plus anciennes méthodes thérapeutiques ont aussi leur place dans certaines situations, comme les verrues intravaginales, urétrales, anales ou récalcitrantes ou encore pour les patientes enceintes. Conclusion Les nouveaux traitements des verrues génitales externes peuvent réduire la douleur causée par la thérapie et le nombre de visites au cabinet. Les autres méthodes thérapeutiques demeurent utiles dans certaines situations.

  12. Voodoo Science

    NASA Astrophysics Data System (ADS)

    Park, Robert

    2011-03-01

    A remarkable scientific result that appears to violate natural law may portend a revolutionary advance in human knowledge. It is, however, more likely an experimental screw up. Error is normal; it can be reduced by repeating measurements and better design of controls, but the success and credibility of science is anchored in a culture of openness. Ideas and observations are freely exposed to independent testing and evaluation by others. What emerges is the book of nature. On its pages we find, if not a simple world, at least an orderly world, in which everything from the birth of stars to falling in love is governed by the same natural laws. These laws cannot be circumvented by any amount of piety or cleverness, they can be understood - with the possible exception of String Theory. For those who elect to work outside the scientific community, errors may go unrecognized. We will examine examples of this, including claims of perpetual motion and cancer caused by cell-phone radiation.

  13. Life sciences.

    PubMed

    Schmidt, Gregory K

    2002-12-01

    Space life sciences research activities are reviewed for the year. Highlights of animal studies were the first long-term flight of an animal enclosure module and an avian development facility on STS-108. Plant research efforts focused on a biomass production system for eventual use on the International Space Station (ISS), the PESTO experiment on ISS, and screening of several salad crop varieties for potential use in space. Health-related studies included the Martian Radiation Environment Experiment (MARIE) on the Mars Odyssey mission, presentation of results from NASA's Biomolecular Physics and Chemistry Program, and research related to human liver cell function in space through an agreement with StelSys. In industry and academia, a memorandum of understanding was signed between NASA and the biotechnology industry to enhance communication between NASA and the industry, expand commercial biotechnology space research and development, and expand formal and informal education of industry and the public regarding biotechnology and space research. NASA selected Purdue University to lead an NSCORT for advanced life support research to develop technologies to enable long-duration planetary mission and sustain human space colonies. PMID:12506925

  14. Science Graduates' Understanding of Science Processes.

    ERIC Educational Resources Information Center

    Iqbal, Hafiz Muhammad

    1998-01-01

    Argues that the nature of science has not been emphasized effectively in the professional training of scientists in Pakistan. Describes how the development of science-process skills, an inquiry approach, and constructive learning is delayed. (DDR)

  15. Security Science as an Applied Science?

    ERIC Educational Resources Information Center

    Smith, Clifton

    2001-01-01

    Describes the development of a security science degree as the emerging applied science of the protection of individuals and assets. Proposes the themes of physical, electronic, information security and facility management as scientific applications for the course. (Author/MM)

  16. Applications of Nuclear Science for Stewardship Science

    NASA Astrophysics Data System (ADS)

    Cizewski, Jolie A.

    2013-03-01

    Stewardship science is research important to national security interests that include stockpile stewardship science, homeland security, nuclear forensics, and non-proliferation. To help address challenges in stewardship science and workforce development, the Stewardship Science Academic Alliances (SSAA) was inaugurated ten years ago by the National Nuclear Security Administration of the U. S. Department of Energy. The goal was to enhance connections between NNSA laboratories and the activities of university scientists and their students in research areas important to NNSA, including low-energy nuclear science. This paper presents an overview of recent research in low-energy nuclear science supported by the Stewardship Science Academic Alliances and the applications of this research to stewardship science.

  17. Apports des Observations infrarouges à l'Etude des Restes de Supernovae

    NASA Astrophysics Data System (ADS)

    Douvion, Thomas

    2000-09-01

    Cette thèse est consacrée à l'étude de la poussière dans les jeunes restes de supernova à partir d'observations principalement faites en infrarouge moyen avec l'instrument ISOCAM du satellite ISO. Après une introduction générale sur les supernovae, les poussières et les observations infrarouges, on montre comment ces dernières mettent en évidence qu'une partie du matériel éjecté par la supernova Cassiopée A s'est condensée en grains de poussière. Une analyse spectroscopique de cette poussière montre une composition à base de silicates, de quartz et d'oxydes d'aluminium. On propose un modèle de chauffage collisionnel par les électrons du plasma dans lequel baignent les poussières, qui permet de rendre compte de leur température. La détection de cette poussière combinée avec l'observation du néon permet d'obtenir des informations uniques sur le mélange des éléments chimiques dans la supernova. Une conséquence de ces résultats est une formation de poussière limitée. Une recherche de poussière dans d'autres restes de supernova galactiques a été effectuée. La poussière observée dans Kepler et Tycho semble d'origine circumstellaire ou interstellaire, et un modèle de chauffage collisionnel nous renseigne sur les conditions physiques régnant dans ces régions. Les observations de la nébuleuse du Crabe font apparaître une forte émission synchrotron qui masque une éventuelle composante de poussière. Ces constatations, ainsi que celles déduites de l'efficacité chimique de formation obtenue à partir des quantités produites observées, permettent de conclure que les supernovae comme Cassiopée A sont actuellement moins efficaces dans la formation des poussières que d'autres objets astrophysiques comme les étoiles évoluées.

  18. Perspectives on the Chaine Des Puys and Limagne Fault UNESCO World Heritage Project

    NASA Astrophysics Data System (ADS)

    van Wyk de Vries, Benjamin; Olive, Cécile

    2015-04-01

    The Chaîne des Puys and Limagne fault project is acknowledged to have Outstanding Universal Value (38th session of the World Heritage UNESCO committee, June 2014). One ongoing challenge for the project is to consolidate the outreach, and to work with other sites to increase the public perception of Earth sciences. The Chaîne des Puys volcanic field in central France, became a celebrated mecca for 18/19th Century scientists, only once the volcanoes were 'discovered'. Beforehand they were only hills, but the ability to interpret landscape with prior knowledge allowed these early geologists to create a popular understanding of the geology. Since that time, the Chaîne des Puys has become a well-known volcanic site to a worldwide audience through textbooks, tourism, and commerce. To the 19th century geologists, the Limagne escarpment was just as fascinating, but lacking the ability to fully interpret this rift margin, the idea of a fault did not percolate down to the general public. With the advent of the current UNESCO project, it became clear that the geological link between the volcanoes and the fault could be exploited, not only to raise the profile of the volcanoes, but to create a greater awareness of the tectonics in the greater public. Not only have the volcanoes, become better known and more clearly understood than previously, but the fault has begun to emerge as a feature in public consciousness. We will demonstrate the many communication techniques at all levels that have been used in the project. We explain the rationale between creating a geological scale model that works on processes as well as landforms to raise the public awareness. The success is that we show how geological features can be made readable by the general public, something highly important for conservation of heritage, but also for risk perception. The increased education efforts of the scientists have also lead to an increase in science. The more informed and participatory the public is, the more efficient the communication can be.

  19. Communicating Geoscience through Geoheritage: The Chaine Des Puys and Limagne Fault Unesco World Heritage Project.

    NASA Astrophysics Data System (ADS)

    Olive-Garcia, C.; van Wyk de Vries, B.

    2014-12-01

    The Chaîne des Puys volcanic field in central France, became a celebrated mecca for 18/19th Century Scientists, only once the volcanoes were 'discovered'. Beforehand they were only hills, but the ability to interpret landscape with prior knowledge allowed these early geologists to create a popular understanding of the geology. Since that time, the Chaîne des Puys has become a well-known volcanic site to a worldwide audience through textbooks, tourism, and commerce (Look at a Volvic water bottle!). To the 19th century geologists, the Limagne escarpment was just as fascinating, but lacking the ability to fully interpret this rift margin, the idea of a fault did not percolate down to the general public. With the advent of the current UNESCO project, it became clear that the geological link between the volcanoes and the fault could be exploited, not only to raise the profile of the volcanoes, but to create a greater awareness of the tectonics in the greater public. Not only have the volcanoes, become better known and more clearly understood than previously, but the fault has begun to emerge as a feature in public consciousness. We will demonstrate the many communication techniques at all levels that have been used in the project. We explain the rationale between creating a geological scale model that works on processes as well as landforms to raise the public awareness. The success is that we show how geological features can be made readable by the general public, something highly important for conservation of heritage, but also for risk perception. The increased education efforts of the scientists have also lead to an increase in science. The Chaîne des Puys and Limagne fault project was discussed at the 38th session of the World Heritage UNESCO committee in June 2014 and was acknowledged to have Universal Exceptional Value: the future challenge for this project is to consolidate the outreach, and to work with other sites to increase the public perception of earth sciences. The more informed and participatory the public is the more efficient the communication can be.

  20. Collaboration and Team Science

    Cancer.gov

    Who is Referencing "Collaboration and Team Science: A Field Guide"? NIH Intramural Research Program Blog Team Science Toolkit Time Ideas Compass - Ohio University The Current - UC Santa Barbara Huffington Post Scripps Translational Science Institute Stanf

  1. Women "and" Science.

    ERIC Educational Resources Information Center

    Galupo, M. Paz; Gasparich, Gail E.

    2000-01-01

    Science and medicine are littered with the images of men. Introduces an interdisciplinary course devoted to the subject of women, gender, and science issues. Discusses possible ways to encourage females to pursue careers in science. (Contains web resources.) (YDS)

  2. Equal Opportunity Science.

    ERIC Educational Resources Information Center

    Mason, Cheryl L.; Barba, Robertta H.

    1992-01-01

    Addresses the need to provide bilingual, Hispanic American students with equal opportunities to learn and excel in science. Discusses the context and content of science education, suggests approaches for bilingual science teaching, and proposes potential solutions to the problems. (MDH)

  3. Nursing science leaders.

    PubMed

    Ortiz, Mario R

    2015-04-01

    This introduces the guest author's column on perspectives on the development of leaders in science. The need for leadership in science is discussed and a model for the development of science leaders in nursing is outlined. PMID:25805390

  4. Mars Science Laboratory Using Laser Instrument, Artist's Concept

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This artist's conception of NASA's Mars Science Laboratory portrays use of the rover's ChemCam instrument to identify the chemical composition of a rock sample on the surface of Mars.

    ChemCam is innovative for planetary exploration in using a technique referred to as laser breakdown spectroscopy to determine the chemical composition of samples from distances of up to about 8 meters (25 feet) away. ChemCam is led by a team at the Los Alamos National Laboratory and the Centre d'Etude Spatiale des Rayonnements in Toulouse, France.

    Mars Science Laboratory, a mobile robot for investigating Mars' past or present ability to sustain microbial life, is in development at NASA's Jet Propulsion Laboratory for a launch opportunity in 2009. The mission is managed by JPL, a division of the California Institute of Technology, Pasadena, Calif., for the NASA Science Mission Directorate, Washington.

  5. Promoting science through science fiction and pseudoscience.

    NASA Astrophysics Data System (ADS)

    Roslund, C.

    1986-11-01

    A great deal of physics can be learned from reading good science fiction. Many writers of this genre have shown great talent in explaining the laws of physics in language that is both lucid and accessible. Their writings can readily be used by the science teacher to enhance and to stimulate student understanding of physics and science.

  6. Science and Religion: Implications for Science Educators

    ERIC Educational Resources Information Center

    Reiss, Michael J.

    2010-01-01

    A religious perspective on life shapes how and what those with such a perspective learn in science; for some students a religious perspective can hinder learning in science. For such reasons Staver's article is to be welcomed as it proposes a new way of resolving the widely perceived discord between science and religion. Staver notes that Western…

  7. Common Earth Science Misconceptions in Science Teaching

    ERIC Educational Resources Information Center

    King, Chris

    2012-01-01

    A survey of the Earth science content of science textbooks found a wide range of misconceptions. These are discussed in this article with reference to the published literature on Earth science misconceptions. Most misconceptions occurred in the "sedimentary rocks and processes" and "Earth's structure and plate tectonics" categories; the most…

  8. Citizen Science: Getting More Involved with Science

    ERIC Educational Resources Information Center

    Leeder, Poppy

    2014-01-01

    One of the things that this author enjoys most about working at the Natural Environment Research Council (NERC) is the science that she finds out about and the researchers she meets. Having loved science throughout school and then on into university, the author is always keen to learn more. The increase in citizen science projects over the last…

  9. Common Earth Science Misconceptions in Science Teaching

    ERIC Educational Resources Information Center

    King, Chris

    2012-01-01

    A survey of the Earth science content of science textbooks found a wide range of misconceptions. These are discussed in this article with reference to the published literature on Earth science misconceptions. Most misconceptions occurred in the "sedimentary rocks and processes" and "Earth's structure and plate tectonics" categories; the most

  10. Hands-On Science. Journals of Science.

    ERIC Educational Resources Information Center

    Kepler, Lynne

    1998-01-01

    Describes how to use journal writing in elementary science classes. Writing lets children communicate observations and ideas while reinforcing understanding of key science concepts. Journal ideas include using notebooks to respond to teacher prompts or write about what students are studying; sharing a classroom science journal; and keeping a…

  11. Diffusion incohérente des neutrons : modèles analytiques pour la dynamique interne des protéines

    NASA Astrophysics Data System (ADS)

    Bicout, D. J.

    2005-11-01

    La dynamique interne des protéines joue un rôle central dans la stabilité, la fonction et l'activité biologique de ces biomolécules. Il est maintenant établi que les fluctuations d'états conformationnels des protéines influencent fortement la plupart des réactions biochimiques et s'accompagnent d'une augmentation brutale des déplacements carrés moyens des atomes au dessus de la température de la transition dynamique. Dans cette contribution, nous présentons une revue critique de quelques modèles théoriques couramment utilisés dans la littérature pour l'analyse des mouvements internes des protéines et la description de la transition dynamique.

  12. Catalog Production for the DES Blind Cosmology Challenge

    NASA Astrophysics Data System (ADS)

    Busha, Michael T.; Wechsler, R. H.; Becker, M. R.; Erickson, B.; Evrard, A. E.

    2013-01-01

    The Blind Cosmology Challenge (BCC) is an effort by the Dark Energy Survey (DES) to test analysis tools for extracting cosmological information using a set of detailed synthetic galaxy catalogs. Here, we describe the creation of these synthetic sky catalogs based on requirements of the optical (DES) and the near-IR VISTA Hemisphere Survey, producing catalogs covering a quarter of the sky to z ˜ 2, with sources complete to r ˜ 25. Starting with a nested set of lightcone outputs of large, N-body simulation, galaxies are assigned to the dark matter distribution using an empirical algorithm that is tunable to match observed evolution of low-order galaxy population properties (counts and spatial clustering) in luminosity-color-density space. Galaxies are lensed by matter along the line of sight (including magnification, shape distortion, and multiple images), using a new algorithm that calculates shear with 3.22 arcsec resolution at galaxy positions in the full catalog. The catalog is well suited to support DES+VISTA joint studies of galaxy clustering, groups and clusters of galaxies, and gravitational lensing, and we highlight their application to the ongoing DES BBCC. Catalogs include ˜320 million galaxies and ˜150 million stars, with realistic colors, shapes and photometric errors. Using the expected DES photometric errors, three independent photometric redshift codes are run on the catalog, two of which produce full probability distributions. The synthetic observable catalog includes object position, magnitudes in the DES and VISTA bands, photometric errors, photometric redshifts, size, ellipticity, for each of ˜ 500 million objects. The galaxy distribution is additionally masked appropriately for the 5000 square degree DES footprint, including the impact of bright stars. In addition, we offer separate catalogs with magnitudes for additional existing and planned surveys, including SDSS, CFHTLS, HSC, LSST, and Euclid.

  13. De l'importance des orbites periodiques: Detection et applications

    NASA Astrophysics Data System (ADS)

    Doyon, Bernard

    L'ensemble des Orbites Periodiques Instables (OPIs) d'un systeme chaotique est intimement relie a ses proprietes dynamiques. A partir de l'ensemble (en principe infini) d'OPIs cachees dans l'espace des phases, on peut obtenir des quantites dynamiques importantes telles les exposants de Lyapunov, la mesure invariante, l'entropie topologique et la dimension fractale. En chaos quantique (i.e. l'etude de systemes quantiques qui ont un equivalent chaotique dans la limite classique), ces memes OPIs permettent de faire le pont entre le comportement classique et quantique de systemes non-integrables. La localisation de ces cycles fondamentaux est un probleme complexe. Cette these aborde dans un premier temps le probleme de la detection des OPIs dans les systemes chaotiques. Une etude comparative de deux algorithmes recents est presentee. Nous approfondissons ces deux methodes afin de les utiliser sur differents systemes dont des flots continus dissipatifs et conservatifs. Une analyse du taux de convergence des algorithmes est aussi realisee afin de degager les forces et les limites de ces schemes numeriques. Les methodes de detection que nous utilisons reposent sur une transformation particuliere de la dynamique initiale. Cette astuce nous a inspire une methode alternative pour cibler et stabiliser une orbite periodique quelconque dans un systeme chaotique. Le ciblage est en general combine aux methodes de controle pour stabiliser rapidement un cycle donne. En general, il faut connaitre la position et la stabilite du cycle en question. La nouvelle methode de ciblage que nous presentons ne demande pas de connaitre a priori la position et la stabilite des orbites periodiques. Elle pourrait etre un outil complementaire aux methodes de ciblage et de controle actuelles.

  14. La planification préalable des soins pour les patients en pédiatrie

    PubMed Central

    2008-01-01

    RÉSUMÉ Les progrès médicaux et technologiques ont permis d’ac-croître les taux de survie et d’améliorer la qualité de vie des nourrissons, des enfants et des adolescents ayant des maladies chroniques mettant la vie en danger. La planifi-cation préalable des soins inclut le processus relié aux discussions sur les traitements essentiels au maintien de la survie et la détermination des objectifs des soins de longue durée. Les dispensateurs de soins pédiatriques ont l’obligation éthique d’assimiler cet aspect des soins médicaux. Le présent document de principes vise à aider les dispensateurs de soins à discuter de la planification préalable des soins des patients pédiatriques dans diverses situations. La planification préalable des soins exige des communications efficaces afin de clarifier les objectifs des soins et de s’entendre sur les traitements pertinents ou non pour réaliser ces objectifs, y compris les mesures de réanimation et les mesures palliatives.

  15. Aktuelle Diagnostik und Behandlung des Basalzellkarzinoms.

    PubMed

    Alter, Mareike; Hillen, Uwe; Leiter, Ulrike; Sachse, Michael; Gutzmer, Ralf

    2015-09-01

    Das Basalzellkarzinom ist der hufigste Tumor des hellhutigen Menschen, altersstandardisiert liegt die Inzidenz bei 63 (Frauen) bzw. 80 (Mnner) pro 100 000 Einwohner pro Jahr in Deutschland. Frhe Lsionen knnen klinisch eine diagnostische Herausforderung darstellen, hier knnen nichtinvasive Diagnoseverfahren wie die optische Kohrenztomographie und die konfokale Laserscanmikroskopie hilfreich sein. Die klinische Verdachtsdiagnose wird in der Regel mittels Gewebeuntersuchung histologisch besttigt. Die Standardtherapie besteht in einer histologisch gesicherten, kompletten Resektion, wahlweise mittels mikrographisch Schnittrand-kontrollierter Chirurgie oder entsprechend der Tumorgre, -lokalisation und Infiltration mit 3-5 und mehr Millimetern Sicherheitsabstand, um das Rezidivrisiko zu mindern. Therapeutisch knnen insbesondere multiple Basalzellkarzinome (wie beim Gorlin-Goltz-Syndrom) oder lokal fortgeschrittene bzw. selten auch metastasierende Basalzellkarzinome ein Problem darstellen. Bei oberflchlichen Basalzellkarzinomen knnen nichtoperative Verfahren wie die photodynamische Therapie oder topische Medikamente erwogen werden. Bei lokal inoperablen oder metastasierenden Basalzellkarzinomen sollten in einer interdisziplinren Tumorkonferenz Therapieempfehlungen ausgesprochen werden, zu den Optionen zhlen in dieser Situation eine Strahlentherapie oder eine Systemtherapie miteinem Hedgehog-Inhibitor. PMID:26882376

  16. Methodes de calcul des forces aerodynamiques pour les etudes des interactions aeroservoelastiques

    NASA Astrophysics Data System (ADS)

    Biskri, Djallel Eddine

    L'aeroservoelasticite est un domaine ou interagissent la structure flexible d'un avion, l'aerodynamique et la commande de vol. De son cote, la commande du vol considere l'avion comme une structure rigide et etudie l'influence du systeme de commande sur la dynamique de vol. Dans cette these, nous avons code trois nouvelles methodes d'approximation de forces aerodynamiques: Moindres carres corriges, Etat minimal corrige et Etats combines. Dans les deux premieres methodes, les erreurs d'approximation entre les forces aerodynamiques approximees par les methodes classiques et celles obtenues par les nouvelles methodes ont les memes formes analytiques que celles des forces aerodynamiques calculees par LS ou MS. Quant a la troisieme methode, celle-ci combine les formulations des forces approximees avec les methodes standards LS et MS. Les vitesses et frequences de battement et les temps d'executions calcules par les nouvelles methodes versus ceux calcules par les methodes classiques ont ete analyses.

  17. Le role du phytoplancton de petite taille (<20 mum) dans les variations des proprietes optiques des eaux du Saint-Laurent

    NASA Astrophysics Data System (ADS)

    Mas, Sebastien

    Les mesures satellitaires de couleur des oceans sont largement determinees par les proprietes optiques inherentes (IOPs) des eaux de surface. D'autre part, le phytoplancton de petite taille (<20 mum) est le plus souvent dominant dans les oceans, et peut donc etre une source importante de variation des IOPs dans les oceans. Dans ce contexte, le but principal de ce doctorat etait de definir l'impact du phytoplancton (<20 mum) sur les variations des proprietes optiques de l'Estuaire et du Golfe du Saint-Laurent (Canada). Afin d'atteindre cet objectif, il etait necessaire de determiner en milieu controle les facteurs de variabilite des proprietes optiques cellulaires et des IOPs du phytoplancton (<20 mum) des eaux du Saint-Laurent, et d'evaluer la contribution du phytoplancton (<20 mum) aux proprietes optiques totales des eaux du Saint-Laurent. Des experiences en laboratoire ont montre que les variations des proprietes optiques des cellules phytoplanctoniques soumises a un cycle jour-nuit, ainsi qu'a des changements concomitants d'intensite lumineuse, peuvent contribuer significativement a la variabilite des proprietes optiques observee en milieu naturel. D'autres experiences ont, quant a elles, mis en evidence que les variations des proprietes optiques des cellules phytoplanctoniques dues aux phases de croissance peuvent alterer les IOPs des oceans, particulierement pendant les periodes de floraison. De plus, la presence de bacteries et de particules detritiques peut egalement affecter la variabilite des IOPs totales, notamment la diffusion. Au printemps, dans l'Estuaire et le Golfe du Saint-Laurent, la contribution du phytoplancton <20 mum aux IOPs presentait des differences regionales evidentes pour les proprietes d'absorption et de diffusion. En plus de la variabilite spatiale, les proprietes optiques cellulaires presentaient des variations journalieres, et ce particulierement pour le picophytoplancton. Enfin, la plupart des differences observees dans les proprietes biooptiques, particulierement l'absorption, etaient attribuables a la contribution du phytoplancton <20 mum. Ceci confirme l'importance de la structure de taille des communautes phytoplanctoniques dans les modeles bio-optiques appliques au Saint-Laurent. L'ensemble des resultats a permis de mettre en evidence l'importance des mecanismes de photoacclimatation et de synchronisation du cycle cellulaire du phytoplancton sur les variations journalieres des IOPs, ainsi que de l'etat physiologique relie au stade de croissance sur les variations temporelles a long terme des IOPs. De plus, le phytoplancton <20 mum contribue de maniere importante aux IOPs et a leur variabilite dans l'Estuaire et le Golfe du St-Laurent, et ce particulierement pour l'absorption. Cette etude de doctorat souligne donc l'importance du phytoplancton <20 mum sur la variabilite des IOPs des oceans.

  18. Photometric redshift analysis in the Dark Energy Survey Science Verification data

    NASA Astrophysics Data System (ADS)

    Sánchez, C.; Carrasco Kind, M.; Lin, H.; Miquel, R.; Abdalla, F. B.; Amara, A.; Banerji, M.; Bonnett, C.; Brunner, R.; Capozzi, D.; Carnero, A.; Castander, F. J.; da Costa, L. A. N.; Cunha, C.; Fausti, A.; Gerdes, D.; Greisel, N.; Gschwend, J.; Hartley, W.; Jouvel, S.; Lahav, O.; Lima, M.; Maia, M. A. G.; Martí, P.; Ogando, R. L. C.; Ostrovski, F.; Pellegrini, P.; Rau, M. M.; Sadeh, I.; Seitz, S.; Sevilla-Noarbe, I.; Sypniewski, A.; de Vicente, J.; Abbot, T.; Allam, S. S.; Atlee, D.; Bernstein, G.; Bernstein, J. P.; Buckley-Geer, E.; Burke, D.; Childress, M. J.; Davis, T.; DePoy, D. L.; Dey, A.; Desai, S.; Diehl, H. T.; Doel, P.; Estrada, J.; Evrard, A.; Fernández, E.; Finley, D.; Flaugher, B.; Frieman, J.; Gaztanaga, E.; Glazebrook, K.; Honscheid, K.; Kim, A.; Kuehn, K.; Kuropatkin, N.; Lidman, C.; Makler, M.; Marshall, J. L.; Nichol, R. C.; Roodman, A.; Sánchez, E.; Santiago, B. X.; Sako, M.; Scalzo, R.; Smith, R. C.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Tucker, D. L.; Uddin, S. A.; Valdés, F.; Walker, A.; Yuan, F.; Zuntz, J.

    2014-12-01

    We present results from a study of the photometric redshift performance of the Dark Energy Survey (DES), using the early data from a Science Verification period of observations in late 2012 and early 2013 that provided science-quality images for almost 200 sq. deg. at the nominal depth of the survey. We assess the photometric redshift (photo-z) performance using about 15 000 galaxies with spectroscopic redshifts available from other surveys. These galaxies are used, in different configurations, as a calibration sample, and photo-z's are obtained and studied using most of the existing photo-z codes. A weighting method in a multidimensional colour-magnitude space is applied to the spectroscopic sample in order to evaluate the photo-z performance with sets that mimic the full DES photometric sample, which is on average significantly deeper than the calibration sample due to the limited depth of spectroscopic surveys. Empirical photo-z methods using, for instance, artificial neural networks or random forests, yield the best performance in the tests, achieving core photo-z resolutions σ68 ˜ 0.08. Moreover, the results from most of the codes, including template-fitting methods, comfortably meet the DES requirements on photo-z performance, therefore, providing an excellent precedent for future DES data sets.

  19. Regles de fusion en theorie des champs conformes

    NASA Astrophysics Data System (ADS)

    Begin, Luc

    1999-10-01

    Les théories de champs conformes constituent un domaine de recherche très actif avec de nombreuses applications en physique statistique, en matière condensée, en théorie des cordes, en mathématiques, etc. Nous analysons ici le calcul des règles de fusion dans les modèles Wess- Zumino-Witten par des méthodes positives. Les règles de fusion sont des quantités importantes puisqu'elles indiquent comment se combinent les champs primaires de la théorie. L'approche présentée est basée sur l'hypothèse que les règles de fusion sont décrites par un système d'inéquations linéaire et homogène et mène au concept original de «base de fusion». Cette approche simple et générale permet d'utiliser les méthodes combinatoires et de programmation linéaire pour construire les fonctions génératrices et les bases de fusion. Cette méthode permet d'obtenir des résultats originaux et explicites pour les algèbres su (3), su (4) et sp (4).

  20. Modelisation des emissions de particules microniques et nanometriques en usinage

    NASA Astrophysics Data System (ADS)

    Khettabi, Riad

    La mise en forme des pieces par usinage emet des particules, de tailles microscopiques et nanometriques, qui peuvent etre dangereuses pour la sante. Le but de ce travail est d'etudier les emissions de ces particules pour fins de prevention et reduction a la source. L'approche retenue est experimentale et theorique, aux deux echelles microscopique et macroscopique. Le travail commence par des essais permettant de determiner les influences du materiau, de l'outil et des parametres d'usinage sur les emissions de particules. E nsuite un nouveau parametre caracterisant les emissions, nomme Dust unit , est developpe et un modele predictif est propose. Ce modele est base sur une nouvelle theorie hybride qui integre les approches energetiques, tribologiques et deformation plastique, et inclut la geometrie de l'outil, les proprietes du materiau, les conditions de coupe et la segmentation des copeaux. Il ete valide au tournage sur quatre materiaux: A16061-T6, AISI1018, AISI4140 et fonte grise.

  1. Science Olympiad students' nature of science understandings

    NASA Astrophysics Data System (ADS)

    Philpot, Cindy J.

    2007-12-01

    Recent reform efforts in science education focus on scientific literacy for all citizens. In order to be scientifically literate, an individual must have informed understandings of nature of science (NOS), scientific inquiry, and science content matter. This study specifically focused on Science Olympiad students' understanding of NOS as one piece of scientific literacy. Research consistently shows that science students do not have informed understandings of NOS (Abd-El-Khalick, 2002; Bell, Blair, Crawford, and Lederman, 2002; Kilcrease and Lucy, 2002; Schwartz, Lederman, and Thompson, 2001). However, McGhee-Brown, Martin, Monsaas and Stombler (2003) found that Science Olympiad students had in-depth understandings of science concepts, principles, processes, and techniques. Science Olympiad teams compete nationally and are found in rural, urban, and suburban schools. In an effort to learn from students who are generally considered high achieving students and who enjoy science, as opposed to the typical science student, the purpose of this study was to investigate Science Olympiad students' understandings of NOS and the experiences that formed their understandings. An interpretive, qualitative, case study method was used to address the research questions. The participants were purposefully and conveniently selected from the Science Olympiad team at a suburban high school. Data collection consisted of the Views of Nature of Science -- High School Questionnaire (VNOS-HS) (Schwartz, Lederman, & Thompson, 2001), semi-structured individual interviews, and a focus group. The main findings of this study were similar to much of the previous research in that the participants had informed understandings of the tentative nature of science and the role of inferences in science, but they did not have informed understandings of the role of human imagination and creativity, the empirical nature of science, or theories and laws. High level science classes and participation in Science Olympiad did not translate into informed understandings of NOS. There were implications that labs with a set procedure and given data tables did not contribute to informed NOS understandings, while explicit instruction may have contributed to more informed understandings. Exploring these high achieving, Science Olympiad students' understandings of NOS was a crucial step to understanding what experiences formed these students' understandings so that teachers may better their practices and help more students succeed in becoming scientifically literate citizens.

  2. Étude comparative des techniques d'analyse par fluorescence X à dispersion d'énergie (ED-XRF) et à dispersion de longueur d'onde (WD-XRF), et par spectrométrie d'émission atomique à source plasma couplée par induction (ICP-AES)

    NASA Astrophysics Data System (ADS)

    Rahmani, A.; Benyaïch, F.; Bounakhla, M.; Bilal, E.; Moutte, J.; Gruffat, J. J.; Zahry, F.

    2004-11-01

    Dans ce travail, nous présentons une étude comparative des techniques d'analyse par fluorescence X à dispersion d'énergie (ED-XRF) et à dispersion de longueur d'onde (WD-XRF), et par spectrométrie d'émission atomique à source plasma couplée par induction (ICP-AES). Les résultats de la calibration des spectromètres à dispersion d'énergie, à excitation par sources radioactives (55Fe, 109Cd et 241Am) et à excitation secondaire (cible secondaire Mo et Cu) du Centre National pour l'Energie, les Sciences et les Techniques Nucléaires (CNESTEN, Rabat, Maroc) sur des échantillons étalons de références de l'Agence International de l'Energie Atomique (AIEA) et du Community Bureau of Référence (BCR) ont été comparés aux résultats d'analyse des mêmes échantillons étalons par la spectrométrie X à dispersion de longueur d'onde (WD-XRF) et par spectrométrie d'émission atomique à source plasma couplé par induction (ICP-AES) au département GENERIC du centre SPIN à l'Ecole des Mines de Saint-Etienne (France). Les trois techniques d'analyse utilisées donnent des résultats comparables pour le dosage des éléments majeurs, alors que pour les traces on note des déviations importantes à cause des effets de matrice qui sont difficiles à corriger dans le cas de la fluorescence X.

  3. Cryptographie quantique avec des tats cohrents longueur d'onde tlcom

    NASA Astrophysics Data System (ADS)

    Lodewyck, J.; Tualle-Brouri, R.; Debuisschert, T.; Grangier, P.

    2006-10-01

    Nous proposons un systme de distribution quantique de cl avec des variables continues, implment avec des technologies tlcom 1550?nm. Le dispositif actuel nous a permis de transmettre une cl secrte brute au taux de 1?Mb/s sur une distance de quelques mtres. Une extension en cours de ralisation nous permettra de transmettre des cls sur des distances allant jusqu' plusieurs dizaines dekilomtres.

  4. Science anc Society

    ScienceCinema

    None

    2011-04-25

    S.P.Worden, membre technique de l'U.S.délégation à Genève pour les négociations sur les armes nucléaires, est physicien, astronome, scientifique et officier de l'armée de l'air. Il parlera des technologies de défense stratégique

  5. Science Fiction & Scientific Literacy

    ERIC Educational Resources Information Center

    Czerneda, Julie E.

    2006-01-01

    The term "science fiction" has become synonymous, in the media at least, for any discovery in science too incredible or unexpected for the nonscientist to imagine. One of the most common classroom uses of science fiction is for students to pick out flaws in science fiction movies or television shows. Unfortunately, this approach can result in…

  6. Social Work and Science

    ERIC Educational Resources Information Center

    Gehlert, Sarah

    2016-01-01

    Interest has grown in the past few years about the place of social work in science. Questions remain, such as whether social work should be considered a science, and if so, where it fits into the constellation of sciences. This article attempts to shed light on these questions. After briefly considering past and present constructions of science

  7. Teaching Middle Grades Science.

    ERIC Educational Resources Information Center

    Georgia State Dept. of Education, Atlanta. Office of Instructional Services.

    Background information and exemplary units for teaching science in Georgia's middle school grades are provided. Discussed in the first section are: (1) the rationale for including science in middle school grades, focusing on science/society/technology, science/social issues, scientific reasoning, and scientific literacy; (2) role of science…

  8. Science for Life

    ERIC Educational Resources Information Center

    Umphrey, Jan

    2011-01-01

    The National Science Teachers Association (NSTA) is committed to promoting excellence and innovation in science teaching and learning for all students. Through the National Science Education Standards, NSTA calls attention to the importance of science standards for all students and the need for a scientifically literate populace. NSTA is also

  9. Science Education and Equity.

    ERIC Educational Resources Information Center

    Bates, Percy; And Others

    1994-01-01

    This double issue of "Equity Coalition" deals with issues related to the need for inclusive science training and encouraging the interest of women and minorities groups in science. The following articles are included: (1) "Say Yes to Science" (Percy Bates); (2) "Science and Equity: Why This Issue Is Important" (Eleanor Linn); (3) "Race Equity and…

  10. Science Learning Centres Roundup

    ERIC Educational Resources Information Center

    Education in Science, 2010

    2010-01-01

    The national network of Science Learning Centres aims to raise the quality of science teaching from Key Stage 1 through post-16 (ages 5-19). Short courses are provided locally through the regional Science Learning Centres and longer, more intensive programmes are available at the National Science Learning Centre in York. There are a growing number…

  11. Implementing Global Science Literacy.

    ERIC Educational Resources Information Center

    Mayer, Victor J., Ed.

    This book expands on the argument for a new type of science curriculum for secondary schools. Instead of being based on each of the major disciplines as are almost all current science curricula, it is suggested that curricula should be conceptually organized around the Earth system, including the science methodology of the system sciences, and…

  12. Project-Based Science

    ERIC Educational Resources Information Center

    Krajcik, Joe

    2015-01-01

    Project-based science is an exciting way to teach science that aligns with the "Next Generation Science Standards" ("NGSS"). By focusing on core ideas along with practices and crosscutting concepts, classrooms become learning environments where teachers and students engage in science by designing and carrying out…

  13. Safe Science: Be Protected!

    ERIC Educational Resources Information Center

    Roy, Ken

    2006-01-01

    More science laboratories are being built because of larger enrollments in academics and schools. There is an increase in hands-on/process science effected by the renewed interest in and priority of science education. New science curricula like Biotechnology and Advanced college type program courses are being introduced with the use of exotic…

  14. Science Fiction & Scientific Literacy

    ERIC Educational Resources Information Center

    Czerneda, Julie E.

    2006-01-01

    The term "science fiction" has become synonymous, in the media at least, for any discovery in science too incredible or unexpected for the nonscientist to imagine. One of the most common classroom uses of science fiction is for students to pick out flaws in science fiction movies or television shows. Unfortunately, this approach can result in

  15. Making Science Relevant

    ERIC Educational Resources Information Center

    Eick, Charles; Deutsch, Bill; Fuller, Jennifer; Scott, Fletcher

    2008-01-01

    Science teachers are always looking for ways to demonstrate the relevance of science to students. By connecting science learning to important societal issues, teachers can motivate students to both enjoy and engage in relevant science (Bennet, Lubben, and Hogarth 2007). To develop that connection, teachers can help students take an active role in

  16. Science, Sciencing and Science Education: An Integrated Approach to Science Education in Early Childhood.

    ERIC Educational Resources Information Center

    Feng, Jianhua

    This article discusses the nature of science and of the child, and the implications of these natures for the teaching of science in the preschool. It is argued that science has three interrelated aspects: content, process, and attitude. Science education should integrate all three aspects. Content can be separated into the areas of physical, life,…

  17. Making Science Relevant

    ERIC Educational Resources Information Center

    Eick, Charles; Deutsch, Bill; Fuller, Jennifer; Scott, Fletcher

    2008-01-01

    Science teachers are always looking for ways to demonstrate the relevance of science to students. By connecting science learning to important societal issues, teachers can motivate students to both enjoy and engage in relevant science (Bennet, Lubben, and Hogarth 2007). To develop that connection, teachers can help students take an active role in…

  18. Science Education Improvement Project.

    ERIC Educational Resources Information Center

    National Science Foundation, New Delhi (India).

    The report covers the activities of the Indian Science Improvement Project during the calendar year 1970. The major emphasis is on curriculum development activities. Topics covered include elementary and secondary school science programs, traveling science workshop, college science improvement program, special college/university program, technical…

  19. Science for Life

    ERIC Educational Resources Information Center

    Umphrey, Jan

    2011-01-01

    The National Science Teachers Association (NSTA) is committed to promoting excellence and innovation in science teaching and learning for all students. Through the National Science Education Standards, NSTA calls attention to the importance of science standards for all students and the need for a scientifically literate populace. NSTA is also…

  20. Senior High Physical Sciences.

    ERIC Educational Resources Information Center

    Murphy, Diane; And Others

    This curriculum guide to the physical sciences was prepared for use in high schools in Duval County, Jacksonville, Florida. Courses covered for grades 10-12 are chemistry, advanced chemistry, physical science, physics, advanced physics, science survey/physical, and science research. For each course, the following elements are included: notes to…

  1. Safe Science: Be Protected!

    ERIC Educational Resources Information Center

    Roy, Ken

    2006-01-01

    Science education is a changing landscape. Changes over the past ten years alone have been both evolutionary and revolutionary--Science Education Standards, new required assessments, science teacher certification issues, science teacher shortages and retirements, molecular approach to Biology, etc. These changes and issues range from…

  2. Immuntherapie des Melanoms: Wirksamkeit und Wirkungsmechanismen.

    PubMed

    Wieder, Thomas; Brenner, Ellen; Braumüller, Heidi; Röcken, Martin

    2016-01-01

    Die Erkenntnisse aus 40 Jahren Forschung erlauben es, durch Antikörper-vermittelte Aktivierung des Immunsystems eine therapeutisch wirksame Antitumorantwort zu induzieren. Die "Immun-Checkpoint-Inhibitoren" sind gegen immuninhibitorische Moleküle wie cytotoxic T lymphocyte antigen 4 (CTLA4), programmed-death-1 (PD-1) oder programmed-death-ligand-1 (PD-L1) gerichtet. Die Unterbrechung der PD-1/PD-L1-Interaktion verbessert mittelfristig auch die Prognose bei Patienten mit Melanomen im Stadium IV. So sind unter Therapie mit Anti-PD-1-Antikörpern 30-60 % dieser Patienten nach eineinhalb Jahren am Leben. Antitumorale Immuntherapien verursachen nur selten eine vollständige Zerstörung der Metastasen, sondern eine Regression um 20-80 %. Fest etabliert ist, dass das Immunsystem Tumorzellen abtöten kann; dies wurde auch für Immuntherapien belegt. Präklinische Daten zeigten jedoch, dass Immunantworten Tumoren nicht nur töten können. So kann das Immunsystem über die Zytokine Interferon-γ und Tumornekrosefaktor in Tumoren einen stabilen Wachstumsarrest hervorrufen, der Seneszenz genannt wird. Ein Ziel antitumoraler Immuntherapien wird also darin liegen, das Überleben der Patienten durch eine langfristige Stabilisierung der Metastasen zu sichern. Dies gilt für das Melanom und das nichtkleinzellige Lungenkarzinom. Sobald Immuntherapien auch bei häufigen Tumoren indiziert sein werden, müssen die Medikamentenpreise deutlich fallen, um sie weiterhin jenen zur Verfügung stellen zu können, die die Therapien benötigen. PMID:26713632

  3. [And Sarah Félix created "L 'Eau des Fées" and "La Parfumerie des Fées"].

    PubMed

    Raynal, Cécile

    2015-12-01

    century, the parisian perfumery of Sarah Felix was famous especially for her cosmetic "L'Eau des Fées" ("Water of the Fairies"), a dyeing supposed to give back to the old hair the color of their youth. Sarah Felix, sister of the famous actress Rachel, exercised several jobs before becoming perfumer. At first, she was actress, then she tried ... oyster culture in Normandy ! Abandoning these activities, Sarah Felix became really a businesswoman in Paris. She dedicated herself to perfumery, in particular to "L'Eau des Fées", from 1866. To launch its product, she was associated to competency characters (engineer, pharmacist, physician) and benefited from the protection of the imperial family. A lawsuit between the associates and the 1870 war hindered the company's early days, but "L'Eau des Fées" provided with quality pledges, imposed itself definitely. The "Parfumerie des Fées" completed the range of its cosmetics with creams, powders, etc. Sarah Félix paid attention to present "L'Eau des Fées" as a dye devoid of toxicity. Was it really the case and could il be sold nowadays? These two issues are discussed in the last part. PMID:26827551

  4. Interactions of diethylstilbestrol (DES) and DES analogs with membrane progestin receptor-alpha and the correlation with their nongenomic progestin activities.

    PubMed

    Tokumoto, Toshinobu; Tokumoto, Mika; Thomas, Peter

    2007-07-01

    Progestin induction of oocyte maturation (OM) in fish is a useful model for investigating endocrine disruption of nongenomic steroid actions. Although diethylstilbestrol (DES) analogs have been shown to mimic the actions of progestins to induce meiotic maturation of goldfish and zebrafish oocytes, their molecular mechanisms of action remain unclear. The ability of these endocrine-disrupting chemicals (EDCs) to interact with the progestin receptor mediating OM was investigated in receptor binding assays using plasma membranes from goldfish ovaries and breast cancer cells transfected with goldfish membrane progestin receptor (mPR)-alpha. Membranes prepared from both ovaries and mPRalpha-transfected cells showed high-affinity, saturable, displaceable, single binding sites specific for the goldfish maturation-inducing steroid, 17alpha,20beta-dihydroxy-4-pregnen-3-one (17,20beta-DHP). DES and DES analogs (dipropionate-DES and hexestrol), which induce OM in goldfish, bound to the receptor and caused concentration-dependent displacement of [3H]-17,20beta-DHP, whereas dimethyl ether-DES had no affinity for the receptor. Scatchard plot analysis of specific 17,20beta-DHP binding in the presence of different amounts of DES showed that DES binding is of the noncompetitive type. The activities of DES and DES analogs to induce meiotic maturation of goldfish oocytes were examined in an in vitro bioassay. Whereas a concentration-dependent induction of OM was observed in response to DES, dipropionate-DES, and hexestrol, dimethyl ether-DES did not show any OM-inducing activity. The close correspondence between binding of DES and its analogs to the mPRalpha protein and their OM-inducing activities suggests a mechanism of endocrine disruption mediated by binding to mPRalpha resulting in its activation, thereby mimicking the nongenomic action of the progestin 17,20beta-DHP. PMID:17446184

  5. A mirror for science.

    PubMed

    Jasanoff, Sheila

    2014-01-01

    Early conceptions of the public understanding of science suffered from a narrow framing of what science means and a presumption that science is divided from its publics by walls of ignorance and indifference. Those assumptions amplified misunderstanding and led to faulty policies. It is time to reopen each element in the term "public understanding of science" to renewed reflection. This journal can advance that goal by encouraging research on actual rather than imagined public responses to science, on representations of science in the public sphere, and on interactions between science, technology and society. PMID:24434707

  6. Problemes en enseignement fonctionnel des langues (Problems in the Functional Teaching of Languages). Publication B-103.

    ERIC Educational Resources Information Center

    Alvarez, Gerardo, Ed.; Huot, Diane, Ed.

    Articles include: (1) "L'elaboration du materiel pedagogique pour des publics adultes" (The Elaboration of Teaching Materials for the Adult Public) by G. Painchaud-Leblanc, (2) "L'elaboration d'un programme d'etudes en francais langue seconde a partir des donnees recentes en didactique des langues" (The Elaboration of a Program of Study in French…

  7. 75 FR 25319 - Agency Information Collection (Survey of Satisfaction With the Disability Evaluation System (DES...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-07

    ... AFFAIRS Agency Information Collection (Survey of Satisfaction With the Disability Evaluation System (DES... Control No. 2900-New (DES)'' in any correspondence. FOR FURTHER INFORMATION CONTACT: Denise McLamb... Control No. 2900-New (DES).'' SUPPLEMENTARY INFORMATION: Title: Survey of Satisfaction with the...

  8. Science in Cinema. Teaching Science Fact through Science Fiction Films.

    ERIC Educational Resources Information Center

    Dubeck, Leroy W.; And Others

    Many feel that secondary school graduates are not prepared to compete in a world of rapidly expanding technology. High school and college students in the United States often prefer fantasy to science. This book offers a strategy for overcoming student apathy toward the physical sciences by harnessing the power of the cinema. In it, ten popular…

  9. Characteristics and trends of POBA in current DES Era.

    PubMed

    Moriya, Manabu; Ishiwata, Sugao; Fujimoto, Yo; Mitani, Haruo; Yamaguchi, Tetsu; Ohno, Minoru

    2015-10-01

    The aim of this study is to clarify the characteristics and trends of POBA in current drug-eluting stent (DES) era. We examined retrospectively the cases of POBA performed in our institute during the years from 2008 to 2012. For control, bare metal stents (BMS) and DES implantation done in 2011 were analyzed. During the period, 85 cases of POBA, 63 BMS and 132 DES were identified. In the result, the rate of restenosis in POBA was significantly higher than BMS and DES (39.7, 14.9, 3.7%, POBA, BMS, DES, respectively, p < 0.001). We assumed three categories depending on the reasons for selecting POBA. (1) Stent delivery failure or expected difficulty of stent delivery due to calcification, etc. (n = 14), (2) intervention for in-stent restenosis or stent thrombosis (n = 34), (3) successful POBA applied to small vessels without complication (n = 14). According to it, category 1 showed significantly high probability of restenosis compared with others [(1) 10/14, 71.4%, (2) 12/34, 35.3%, 3; 2/14, 14.3%, p < 0.05]. In addition, category 3 showed nearly as good as BMS. Balloons used in POBA contained 32 non-compliant balloons and 14 scoring balloons, whereas 30 were semi-compliant balloons only. ACC/AHA lesion type B2/C was 85.7, 45.7 and 50.0%, and cases treated only with semi-compliant balloon were 57.1, 14.3, 92.9% (category (1), (2) and (3), respectively, both p < 0.05). Therefore, this fact shows that a case of small vessel of which diameter is less than 2.5 mm would have a favorable outcome with POBA when treated well only with semi-compliant balloon under the current DES era. PMID:25603774

  10. Holography: science and art

    NASA Astrophysics Data System (ADS)

    Boone, Pierre M.

    1998-09-01

    Art and science are separated by a very large distance nowadays. Long ago, e.g. in Renaissance, or even earlier, in classic Greece and Rome, or still earlier in Egypt or Mesopotamia, arts and sciences were united. Today they seem to go separate paths: science for the industry, arts for the gallery. Holography is an exception: no art without science, but also no science without art.

  11. Science sequence design

    NASA Technical Reports Server (NTRS)

    Koskela, P. E.; Bollman, W. E.; Freeman, J. E.; Helton, M. R.; Reichert, R. J.; Travers, E. S.; Zawacki, S. J.

    1973-01-01

    The activities of the following members of the Navigation Team are recorded: the Science Sequence Design Group, responsible for preparing the final science sequence designs; the Advanced Sequence Planning Group, responsible for sequence planning; and the Science Recommendation Team (SRT) representatives, responsible for conducting the necessary sequence design interfaces with the teams during the mission. The interface task included science support in both advance planning and daily operations. Science sequences designed during the mission are also discussed.

  12. The World of Science Fiction.

    ERIC Educational Resources Information Center

    Schwartz, Sheila

    1971-01-01

    Science fiction is discussed from the following standpoints: What Is Science Fiction?; The History of Science Fiction; and The Themes of Science Fiction. A list of films, books, and records about science fiction is given. (DB)

  13. Amplification paramtrique de polaritons dans des microcavits semi-conductrices

    NASA Astrophysics Data System (ADS)

    Baas, A.; Karr, J.-P.; Courty, J.-M.; Giacobino, E.

    2002-06-01

    Nous tudions l'mission non linaire de microcavits serai-conductrices en rgime de couplage fort. Des expriences en rgime d'excitation continue et rsonante ont t rcemment interprtes par un modle de mlange paramtrique quatre ondes de polaritons[1]. Nous avons retrouv cette mission non linaire dans une configuration nouvelle. Nous avons mis en vidence pour la premire fois la dpendance en phase de l'mission, preuve de la cohrence du processus d'amplification. De plus, certaines quadratures du champ rflchi ont des fluctuations rduites en dessous du bruit thermique, et proches de la limite quantique standard[2

  14. "Applied science": a phrase in search of a meaning.

    PubMed

    Bud, Robert

    2012-09-01

    The term "applied science," as it came to be popularly used in the 1870s, was a hybrid of three earlier concepts. The phrase "applied science" itself had been coined by Samuel Taylor Coleridge in 1817, translating the German Kantian term "angewandte Wissenschaft." It was popularized through the Encyclopaedia Metropolitana, which was structured on principles inherited from Coleridge and edited by men with sympathetic views. Their concept of empirical as opposed to a priori science was hybridized with an earlier English concept of "practical science" and with "science applied to the arts," adopted from the French. Charles Dupin had favored the latter concept and promoted it in the reconstruction of the Conservatoire Nationale des Arts et Métiers. The process of hybridization took place from the 1850s, in the wake of the Great Exhibition, as a new technocratic government favored scientific education. "Applied science" subsequently was used as the epistemic basis for technical education and the formation of new colleges in the 1870s. PMID:23286192

  15. Troubles des conduites alimentaires et tempérament cyclothymique: étude transversale à propos de 107 étudiants Tunisiens

    PubMed Central

    Jaweher, Masmoudi; Sonda, Trabelsi; Uta, Ouali; Inès, Feki; Rim, Sallemi; Imene, Baati; Abdelaziz, Jaoua

    2014-01-01

    Introduction Les objectifs de notre étude ont été d'estimer la prévalence des troubles des conduites alimentaires (TCA) chez les jeunes tunisiens et étudier la relation entre le tempérament cyclothymique et les TCA. Méthodes Nous avons ainsi mené une étude transversale descriptive et analytique. Elle a concerné 107 étudiants de l'Institut de Presse et des Sciences de l'Information de la Manouba, Tunisie. Pour l’évaluation des TCA, nous avons procédé par la passation de l'auto questionnaire EAT 40, dans sa version validée en Tunisie. C'est l'outil le plus utilisé pour le dépistage des TCA dans le monde. Pour l’évaluation du tempérament cyclothymique, nous avons utilisé le TEMPS A dans sa version arabe validée. Une fiche épidémiologique associée a permis de recueillir quelques facteurs sociodémographiques et hygiéno-diététiques. Résultats La prévalence des troubles de conduites alimentaires a été de 24,3%. Le pourcentage des étudiants ayant un score de tempérament cyclothymique ≥14 a été de 37,4%. Une association a été trouvée entre les troubles de conduites alimentaires et le tempérament affectif cyclothymique que ce soit selon l'approche dimensionnelle (p=0,005) ou selon celle catégorielle (p=0,046). Le tempérament cyclothymique multiplie par deux le risque de développer un TCA chez les étudiants de sexe féminin (p=0,04). Conclusion Es TCA sont fréquents chez nos étudiants particulièrement de sexe féminin. De plus, la présence d'un tempérament cyclothymique associé permettrait de suspecter doublement une appartenance au spectre bipolaire et devrait conduire à une attention particulière de la part du clinicien pour définir au mieux les stratégies thérapeutiques. PMID:25404977

  16. Science Film: An Aperture into Science Advocacy

    NASA Astrophysics Data System (ADS)

    2015-04-01

    The current funding environment for scientific research necessitates a change in how we foster support for the endeavor. Federal spending is not likely to grow unless constituents--APS members--help communicate the value of science to members of Congress and the public in a compelling and individual way. The event explores how popular film with science-based plots can help physicists communicate the value of science to members of Congress and an increasingly diverse electorate.

  17. Competitive Science: Is Competition Ruining Science?

    PubMed Central

    Casadevall, Arturo

    2015-01-01

    Science has always been a competitive undertaking. Despite recognition of the benefits of cooperation and team science, reduced availability of funding and jobs has made science more competitive than ever. Here we consider the benefits of competition in providing incentives to scientists and the adverse effects of competition on resource sharing, research integrity, and creativity. The history of science shows that transformative discoveries often occur in the absence of competition, which only emerges once fields are established and goals are defined. Measures to encourage collaboration and ameliorate competition in the scientific enterprise are discussed. PMID:25605760

  18. Apport des neutrons à l'analyse structurale des composés partiellement désordonnés

    NASA Astrophysics Data System (ADS)

    Cousson, A.

    2003-02-01

    La cristallographie est un outil extrêmement puissant qui pourrait être utilisé par de nombreux scientifiques dont les sujets de recherche sont en fait très éloignés. L'évolution des techniques ces dernières années a relégué par exemple la cristallographie des rayons X des petites molécules à un rôle mineur, un rôle de service. Certains ont même le sentiment semble-t-il que toutes les connaissances sont contenues dans de multiples logiciels capables par eux-mêmes de conduire une analyse structurale à un résultat correct unique. Il est souhaitable que chacun soit capable de réaliser l'étude structurale du composé qui l'intéresse et bien entendu nécessaire de comprendre ce que l'on fait, la qualité des résultats et leur analyse en dépend. L'objet de cette présentation est de montrer l'apport spécifique de la diffraction de neutrons sur monocristaux à l'étude du désordre, en particulier des atomes d'hydrogène, et ses conséquences sur la compréhension des propriétés physiques, à partir de développements et d'exemples récents.

  19. 75 FR 4882 - Subcommittee on Forensic Science; Committee on Science; National Science and Technology Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-29

    ... From the Federal Register Online via the Government Publishing Office OFFICE OF SCIENCE AND TECHNOLOGY POLICY Subcommittee on Forensic Science; Committee on Science; National Science and Technology... Executive Branch responses to the National Academy of Sciences 2009 report: ``Strengthening Forensic...

  20. 76 FR 38430 - Subcommittee on Forensic Science; Committee on Science; National Science and Technology Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-30

    ... From the Federal Register Online via the Government Publishing Office OFFICE OF SCIENCE AND TECHNOLOGY POLICY Subcommittee on Forensic Science; Committee on Science; National Science and Technology... interoperability issues identified in the National Academy of Sciences 2009 report: ``Strengthening...

  1. 76 FR 6163 - Subcommittee on Forensic Science; Committee on Science; National Science and Technology Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... From the Federal Register Online via the Government Publishing Office OFFICE OF SCIENCE AND TECHNOLOGY POLICY Subcommittee on Forensic Science; Committee on Science; National Science and Technology... interoperability issues identified in the National Academy of Sciences 2009 report: ``Strengthening...

  2. Symetries et integrabilite des equations aux differences finies

    NASA Astrophysics Data System (ADS)

    Lafortune, Stephane

    2000-09-01

    La présente thèse porte sur l'étude des symétries et des propriétés d'intégrabilité des équations aux différences finies. Dans le chapitre 1, le groupe de symétrie ponctuelle d'un système couplé à deux équations différentielles aux différences est étudié. On montre que dans certains cas, la dimension du groupe peut être infinie. Les équations peuvent décrire l'interaction de deux longues chaînes moléculaires, chacune étant composée d'atomes d'un même type. Dans le chapitre 2, une classe de théories de champs avec interaction exponentielle est introduite. L'interaction dépend de deux matrices de ``couplage'' et est suffisamment générale pour inclure toutes les théories de champs de Toda existant dans la littérature. Les symétries de Lie ponctuelles sont obtenues pour les cas où l'on a un nombre fini, infini ou semi-infini de champs. Une attention spéciale est accordée à la présence de l'invariance conforme. Dans le chapitre 3, nous procédons à la classification et à l'étude d'équations linéarisables. Nous examinons tout d'abord l'équation de Gambier continue qui contient, comme réductions, toutes les équations de deuxième ordre intégrables par linéarisation. Nous introduisons par la suite la forme discrète de cette équation et obtenons les conditions d'intégrabilité à l'aide du confinement des singularités. Nous étudions aussi les différentes réductions du cas discret. De plus, nous obtenons des transformations de Schlesinger pour les équations de Gambier discrète et continue. Dans la dernière partie du chapitre, nous étudions une famille d'équations discrètes du deuxième ordre incluant des équations résolubles par linéarisation. Plusieurs cas intégrables sont obtenus. Dans le cas discret, l'étude de l'intégrabilité est faite à l'aide du confinement des singularités. Dans le chapitre 4, nous étudions un autre critère d'intégrabilité: l'entropie algébrique. Nous montrons que les résultats obtenus avec ce critère pour les équations linéarisables sont les mêmes que ceux obtenus avec le confinement des singularités. Nous obtenons de plus une méthode algorithmique pour la détection de la linéarisabilité. Le chapitre 5 est consacré à l'étude d'équations du troisième ordre. Nous obtenons des équations intégrables par des couplages d'équations du premier et du deuxième ordre. Les équations continues sont étudiées à l'aide de l'analyse de Painlevé et le confinement des singularités est utilisé dans le cas discret.

  3. Transport de paires EPR dans des structures mesoscopiques

    NASA Astrophysics Data System (ADS)

    Dupont, Emilie

    Dans cette these, nous nous sommes particulierement interesses a la propagation de paires EPR1 delocalisees et localisees, et a l'influence d'un supraconducteur sur le transport de ces paires. Apres une introduction de cette etude, ainsi que du cadre scientifique qu'est l'informatique quantique dans lequel elle s'inscrit, nous allons dans le chapitre 1 faire un rappel sur le systeme constitue de deux points quantiques normaux entoures de deux fils supraconducteurs. Cela nous permettra d'introduire une methode de calcul qui sera reutilisee par la suite, et de trouver egalement le courant Josephson produit par ce systeme transforme en SQUID-dc par l'ajout d'une jonction auxiliaire. Le SQUID permet de mesurer l'etat de spin (singulet ou triplet), et peut etre forme a partir d'autres systemes que nous etudierons ensuite. Dans le chapitre 2, nous rappellerons l'etude detaillee d'un intricateur d'Andreev faite par un groupe de Bale. La matrice T, permettant d'obtenir le courant dans les cas ou les electrons sont separes spatialement ou non, sera etudiee en detail afin d'en faire usage au chapitre suivant. Le chapitre 3 est consacre a l'etude de l'influence du bruit sur le fonctionnement de l'intricateur d'Andreev. Ce bruit modifie la forme du courant jusqu'a aboutir a d'autres conditions de fonctionnement de l'intricateur. En effet, le bruit present sur les points quantiques peut perturber le transport des paires EPR par l'intermediaire des degres de liberte. Nous montrerons que, du fait de l'"intrication" entre la charge de la paire et le bruit, la paire est detruite pour des temps longs. Cependant, le resultat le plus important sera que le bruit perturbe plus le transport des paires delocalisees, qui implique une resonance de Breit-Wigner a deux particules. Le transport parasite n'implique pour sa part qu'une resonance de Breit-Wigner a une particule. Dans le chapitre 4, nous reviendrons au systeme constitue de deux points quantiques entoures de deux fils supraconducteurs, mais ici, les deux points quantiques seront aussi supraconducteurs. On obtiendra alors l'hamiltonien effectif de la meme maniere que precedemment ainsi que la forme du courant. Dans le cas ou la tension entre les deux fils est nulle, nous ferons une comparaison avec l'experience et nous verrons que les resultats obtenus sont plus en accord avec celle-ci si on fait l'hypothese de la presence d'un bain, qui va modeliser le bruit sur l'un des fils. Enfin, dans le dernier chapitre, nous utiliserons a la fois un qubit de charge et un qubit de spin entoures par deux fils supraconducteurs. Nous pourrons alors mesurer l'influence du supraconducteur et voir s'il est possible de creer ici des paires d'electrons intriques et d'aboutir a un pendule quantique. 1Il existe des systemes qui produisent des paires de particules ejectees simultanement dans des directions opposees et qui permettent de tester le paradoxe d' Einstein, Podolsky, Rosen. Chaque particule de la paire est dans un etat indetermine. Si on mesure les etats respectifs des deux particules, on obtient systematiquement des resultats complementaires, soit de facon aleatoire: 0-1 ou 1-0. La mecanique quantique explique que les deux particules ainsi produites constituent un seul systeme, une paire EPR.

  4. Enhancing international earth science competence in natural hazards through 'geoNatHaz

    NASA Astrophysics Data System (ADS)

    Giardino, Marco; Clague, John J.

    2010-05-01

    "geoNatHaz" is a Transatlantic Exchange Partnership project (TEP 2009-2012) within the framework of the EU-Canada programme for co-operation in higher education, training, and youth. The project is structured to improve knowledge and skills required to assess and manage natural hazards in mountain regions. It provides student exchanges between European and Canadian universities in order to enhance international competence in natural hazard research. The university consortium is led by Simon Fraser University (Canada) and Università degli studi di Torino (Italy). Partner universities include the University of British Columbia, Queen's University, Università di Bologna, Université de Savoie, and the University of Athens. Université de Lausanne (Switzerland) supports the geoNatHaz advisory board through its bilateral agreements with Canadian partner universities. The geoNatHaz project promotes cross-cultural understanding and internationalization of university natural hazard curricula through common lectures, laboratory exercises, and field activities. Forty graduate students from the seven Canadian and European partner universities will benefit from the project between 2009 and 2012. Some students enrolled in graduate-level earth science and geologic engineering programs spend up to five months at the partner universities, taking courses and participating in research teams under the direction of project scientists. Other students engage in short-term (four-week) exchanges involving training in classic natural hazard case-studies in mountain regions of Canada and Europe. Joint courses are delivered in English, but complementary cultural activities are offered in the languages of the host countries. Supporting organizations offer internships and technical and scientific support. Students benefit from work-study programs with industry partners. Supporting organizations include government departments and agencies (Geological Survey of Canada; CNR-IRPI National Research Institute on Hydrogeological Hazards; Simon Fraser University Centre for Natural Hazard Research; Civil Protection of Regione Piemonte; Dipartimento Difesa del Suolo of Regione Valle d'Aosta; Environmental Protection, Civil Protection and Geological Survey of Regione Emilia-Romagna; Alberta Geological Survey), non-governmental and non-profit organizations (Fondazione Vaiont; Fondation Montaine Sure; Comitato Glaciologico Italiano; Tele-Rilevamento Europa; IMAGEO), and companies (MacDonald, Detwiller and Associates; TRE-Canada; BC Hydro; CVA). Support programs to ensure that students fully benefit from their exchanges are in place in each of the participating universities. Exchanges of faculty and technicians will ensure that students' educational experiences are challenging, rich, and intellectually rewarding. The exchanges also will facilitate development of up-to-date natural hazard courses shared by the seven partner universities and will catalyze collaborations among scientists participating in the project. The centrepiece of the project is field-based courses in natural hazards and risk in high mountain environments. Six field courses will be offered over the three-year period of the project - three in Europe and three in Canada. Course topics include (1) impacts of climate change on natural hazards in high mountains, (2) deep-seated rock-slope deformation, (3) mitigation of landslide hazards in mountain valleys, (4) applications of new technologies in natural hazard research, (5) frequency-magnitude relations and risk assessment, and (6) earthquake hazards and risk in mountain regions. The courses are taught by faculty from each of the partner universities, with the assistance of graduate students and technicians. The field courses support and extend existing programs in geology, geomorphology, and engineering geology offered by the partner universities.

  5. Modernizing science education

    NASA Astrophysics Data System (ADS)

    Dehart Hurd, Paul

    2002-01-01

    This article is focused on changes taking place in the teaching of science as part of general education. Over the past century a host of changes in the nature and practice of science have served to make outmoded the science curricula now found in school textbooks. Past and present reform efforts have been limited to updating traditional subject matter, which is not adequate for life and living in today's world. A new framework is required for a general education in science, one that is student centered and up-to-date on the nature of science technology. As stated in the Science Bulletin ([2000]), Science and technology have become the driving force for mankind's quest for a better society (p. 1). The new science curriculum also should be focused on the utilization of science technology for public welfare and human benefit.

  6. Focus on science education

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    That the quality of precollege science and mathematics education in this country is sagging is not news. What is noteworthy, though, is that the science community is sizing up the dilemma and beginning to take official action. Last month, the National Academy of Sciences (NAS) hosted a National Convocation on Precollege Education in Mathematics and Science, and the American Association for the Advancement of Science (AAAS) and its affiliate societies met to form a coalition of affiliate societies on science and mathematics education. In addition, in mid-April the National Science Board, the policy-making arm of the National Science Foundation (NSF), announced the establishment of a new Commission on Precollege Education in Mathematics, Science, and Technology.

  7. Régimes transitoires des photopiles: durée de vie des porteurs et vitesse de recombinaison

    NASA Astrophysics Data System (ADS)

    Mialhe, P.; Sissoko, G.; Pelanchon, F.; Salagnon, J. M.

    1992-12-01

    A detailed analysis of a new experimental practice of the open circuit voltage decay method and of the short circuit current decay method for determining the base minority carrier lifetime and the back surface recombination velocity in solar cells has been performed. The measurements have been made by using the monitoring of a single transient of an operating cell at any level of injection; no power supply is required and a constant illumination level imposes the carrier injection level for normal operating conditions. The theory considers the complete continuity equation including generation and recombination rates of carriers. Precision and sensitivity of the method have been compared. The necessity of a precise knowledge of cell structural parameters have been shown to impose a limitation of the practical use of short-circuit current decay method, to low illumination levels. Cette étude développe une nouvelle méthode expérimentale pour mesurer la durée de vie des porteurs minoritaires dans la base d'une photopile ainsi que la vitesse de recombinaison à son interface arrière. Au cours de la mesure, la photopile est maintenue sous un éclairement constant qui impose le niveau d'injection souhaité. Cette méthode permet d'éliminer les effets néfastes à la mesure, provenant des impédances, propres au composant. Un régime transitoire, provoqué par une variation d'impédance, est étudié au cours de fonctionnements dans des conditions de court-circuit ou de circuit ouvert. L'étude théorique souligne la prise en compte de l'ensemble des phénomènes de recombinaison. L'obtention d'une bonne précision des mesures nécessite, avec une expérimentation rigoureuse, une connaissance précise des paramètres de structure de la photopile étudié. Pour la mesure de la durée de vie des porteurs, la plus grande sensibilité de la méthode en régime transitoire de court-circuit, comparée au régime de circuit ouvert, impose des mesures sous faible illumination.

  8. Opération multimode transverse des OPOs: des structures classiques aux corrélations quantiques

    NASA Astrophysics Data System (ADS)

    Martinelli, M.; Ducci, S.; Gigan, S.; Treps, N.; Maître, A.; Fabre, C.

    2002-06-01

    Nous démontrons la formation de structures transverses sur les faisceaux émis par un oscillateur paramétrique optique (OPO) de type II en configuration confocale. D'un point de vue classique nous mettons en évidence le caractère multimode transverse de telles structures. A travers l'étude des corrélations spatiales des faisceaux générés nous montrons que ces structures sont également multimodes d'un point de vue quantique.

  9. Mesure des inhomogénéités du potentiel gravitationnel galactique.

    NASA Astrophysics Data System (ADS)

    Chereul, E.; Crézé, M.; Bienaymé, O.

    Les hypothèses envisagées pour expliquer les modes de chauffage du disque galactique ne permettent pas de rendre compte complètement du phénomène observé. L'objectif de ce travail est de poser des contraintes sur les échelles et amplitudes caractéristiques des inhomogénéités du potentiel gravitationnel galactique dans le voisinage solaire en opérant une analyse en ondelette des distributions dans l'espace des phases d'un échantillon homogène des données d'Hipparcos.

  10. Vienna University Observatory and Bruno Thüring (German Title: Die Wiener Universitätssternwarte und Bruno Thüring )

    NASA Astrophysics Data System (ADS)

    Kerschbaum, Franz; Posch, Thomas; Lackner, Karin

    We investigate Bruno Thüring's political attitude during the time of National Socialism, based on material from the Vienna Observatory archive, and on statements by his contemporaries. The contribution focuses on the filling of astronomy positions in Vienna, and also on the expulsion of Kasimir Graff. A central role is played by Wilhelm Führer, Obersturmführer der Waffen-SS (Senior Storm Leader of the Armed Protection Squad) and chief civil servant in the Reich science ministry. The transcription of an original letter of 1939 by Führer, addressed to Thüring, is given.

  11. LA SCIENCE ET L'ENSEIGNEMENT DES LANGUES VIVANTES (RESEARCH AND THE TEACHING OF MODERN LANGUAGES).

    ERIC Educational Resources Information Center

    MALECOT, ANDRE

    THE FUNDAMENTAL PRINCIPLES INHERENT IN CURRENT METHODS OF MODERN LANGUAGE TEACHING ARE DISCUSSED AT LENGTH, WITH EMPHASIS ON THE IMPLICATIONS FOR PEDAGOGY DERIVED FROM THE SCIENTIFIC STUDY OF LANGUAGE. THE IMPACT OF PHILOGICAL AND LINGUISTIC STUDIES OF "EXOTIC LANGUAGES" ON TRADITIONAL GRAMMATICAL CONCEPTS AND TERMINOLOGY IS HIGHLIGHTED IN THE…

  12. Analyse des interactions energetiques entre un arena et son systeme de refrigeration

    NASA Astrophysics Data System (ADS)

    Seghouani, Lotfi

    La presente these s'inscrit dans le cadre d'un projet strategique sur les arenas finance par le CRSNG (Conseil de Recherche en Sciences Naturelles et en Genie du Canada) qui a pour but principal le developpement d'un outil numerique capable d'estimer et d'optimiser la consommation d'energie dans les arenas et curlings. Notre travail s'inscrit comme une suite a un travail deja realise par DAOUD et coll. (2006, 2007) qui a developpe un modele 3D (AIM) en regime transitoire de l'arena Camilien Houde a Montreal et qui calcule les flux de chaleur a travers l'enveloppe du batiment ainsi que les distributions de temperatures et d'humidite durant une annee meteorologique typique. En particulier, il calcule les flux de chaleur a travers la couche de glace dus a la convection, la radiation et la condensation. Dans un premier temps nous avons developpe un modele de la structure sous la glace (BIM) qui tient compte de sa geometrie 3D, des differentes couches, de l'effet transitoire, des gains de chaleur du sol en dessous et autour de l'arena etudie ainsi que de la temperature d'entree de la saumure dans la dalle de beton. Par la suite le BIM a ete couple le AIM. Dans la deuxieme etape, nous avons developpe un modele du systeme de refrigeration (REFSYS) en regime quasi-permanent pour l'arena etudie sur la base d'une combinaison de relations thermodynamiques, de correlations de transfert de chaleur et de relations elaborees a partir de donnees disponibles dans le catalogue du manufacturier. Enfin le couplage final entre l'AIM +BIM et le REFSYS a ete effectue sous l'interface du logiciel TRNSYS. Plusieurs etudes parametriques on ete entreprises pour evaluer les effets du climat, de la temperature de la saumure, de l'epaisseur de la glace, etc. sur la consommation energetique de l'arena. Aussi, quelques strategies pour diminuer cette consommation ont ete etudiees. Le considerable potentiel de recuperation de chaleur au niveau des condenseurs qui peut reduire l'energie requise par le systeme de ventilation de l'arena a ete mis en evidence. Mots cles. Arena, Systeme de refrigeration, Consommation d'energie, Efficacite energetique, Conduction au sol, Performance annuelle.

  13. Étude par diffraction des rayons X des vernis rouges des sigillées du sud de la Gaule. Les ateliers de la Graufesenque

    NASA Astrophysics Data System (ADS)

    Vendier, L.; Sciau, Ph.; Dooryhee, E.

    2002-07-01

    La Graufesenque (Millau, Aveyron) 1^rst and 2^nd, centuries AC Sigillata red slips have been studied by x-ray diffraction at ESRF and on a conventional diffractometer. Although x-ray diffraction is a non-destructive characterisation technique adapted to surface study, it has not been used so mutch for Sigillata slip characterisation. The poor quality of the slip surface can be an explanation. In this work we demonstrate that it is possible to get good quality diffraction diagrams on 20-120 AC Sigillata slips. The results confirm the productions homogeneity and the hypothesis about a non-local clay used for the slips. On a counterpart, the late (second half of 2^nd century AC) Sigillata study needs because of their crackled surface a high quality beam, which can only be accessible on a synchrotron installation. These productions seems to be more heterogeneous: some Sigillata present similar diffraction diagrams for the slip and ceramic body (same clay?), some others present results similar to the precedent production period ones. Les vernis rouges de poteries sigillées (I^er et II^e siècles) de la Graufesenque (Millau, Aveyron) ont été étudiés par diffraction des rayons X à la fois à l'ESRF et sur une installation classique de laboratoire. Bien que la diffraction des rayons X soit une technique adaptée à l'étude des surfaces, cette technique a jusqu'à présent assez peu servi dans l'examen de ces objets. Ceci peut en partie s'expliquer par le mauvais état de surface de certains vernis. Dans ce travail, nous montrons que moyennant quelques précautions, il est possible d'obtenir sur une installation classique de bons diffractogranunes des vernis des sigillées datés entre 20 et 120 ap. J.C. Les résultats confirment l'homogénéité de ces productions et l'hypothèse selon laquelle ces vernis n'ont pas été fabriqués à partir des argiles locales du jurassique environnant le site. Par contre, l'étude des sigillées tardives de la deuxième moitié du II^e siècle, dont les vernis sont très écaillés, nécessite une qualité de faisceau inaccessible sur une installation classique, et ne peut être réalisée que sur une source de lumière de type synchrotron. Ces productions semblent plus hétérogènes : certaines sigillées tardives ont un vernis qui pourrait avoir été élaboré à partir de l'argile locale, tandis que d'autres ont encore le vernis des sigillées de la période précédente.

  14. Modlisation et incertitude : comparison de deux mthodes pour l'estimation de la confiance des rsultats des modles numriques

    NASA Astrophysics Data System (ADS)

    Aude, P.; Depecker, P.; Krauss, G.

    1997-01-01

    The problem developed and analyzed in this paper is that of the estimation of the uncertainty associated with the results obtained by numerical simulation codes of physical systems induced from input data. In the first section, a general problem is developed and the authors describe briefly the methods used to calculate the uncertainty domain. They present two classic methods, one is a probability method, the Monte-Carlo method; the other, a determinist method, a differential analysis with finite differences. In the second section, two examples of models of thermal behaviour of building are used to underline the advantages and the drawbacks of both methods. These models are extracted fractions of larger models allowing a simplified presentation of the methods proposed. The authors determine the uncertainty domains on outputs simultaneously with the two methods. They show that the obtained domain by differential analysis is lightly pessimistic, but very near to those of the Monte-Carlo method, in the case of first model, linear, like in the case of second, highly nonlinear. The differential analysis is clearly more economical in calculation time and makes it possible to identify sensitive data with significant bearing on output uncertainty. Nevertheless, it is emphasized that for this method it is essential to enter into the calculation code formalism. globally, the authors conclude that a relative superiority of the differential analysis exists, particularly in the case of large codes where Monte-Carlo use would be prohibitive in calculation time. Le problme dvelopp dans ce texte est celui de l'estimation de l'incertitude associe aux rsultats produits par les codes de simulation numrique des systmes physiques, induite par les incertitudes des donnes d'entre. Dans la premire partie, les auteurs posent le problme gnral et dcrivent brivement les mthodes utilises pour calculer l'amplitude du domaine d'incertitude. Ils prsentent deux mthodes types, l'une probabiliste, la mthode de Monte-Carlo, l'autre dterministe, l'analyse diffrentielle aux diffrences finies. Dans la deuxime partie, deux exemples de modles de comportement thermique de locaux de btiments sont utiliss pour mettre en vidence les avantages et les inconvvients des deux mthodes. Ces modles sont des fractions extraites de grands modles, permettant de simplifier la prsentation des mthodes proposes. Pour le premier, les changes thermiques sont dcoupls et on ne traite pas la covection, ce qui conduit la rsolution d'un systme linaire des radiosits de dimension 10. Les auteurs montrent ainsi que l'incertitude relative de la norme du vecteur des radiosits est de l'ordre de 19?%, pour des incertitudes de donnes exprimentales usuelles. Pour le second, les changes sont coupls et le modle est fortement non linaire. Les incertitudes obtenues pour les tempratures de surface des parois du local tudi sont de l'ordre de 3?%. Les auteurs concluent en faveur de l'analyse diffrentielle, nettement plus conome en temps de calcul et permettant d'identifier les entres sensibles agissant de manire prpondrante sur l'incertitude des sorties. Nanmoins, on souligne, pour cette mthode, la ncessit d'entrer dans le formalisme du code de calcul. Globalement, les auteurs concluent une relative supriorit de l'analyse diffrentielle, en particulier dans le cas des grands codes dont l'exploitation en Monte-Carlo serait prohibitive en temps de calcul.

  15. Differentiating Science Instruction: Secondary Science Teachers' Practices

    ERIC Educational Resources Information Center

    Maeng, Jennifer L.; Bell, Randy L.

    2015-01-01

    This descriptive study investigated the implementation practices of secondary science teachers who differentiate instruction. Participants included seven high school science teachers purposefully selected from four different schools located in a mid-Atlantic state. Purposeful selection ensured participants included differentiated instruction (DI)…

  16. Discovery in Science and in Teaching Science

    ERIC Educational Resources Information Center

    Kipnis, Nahum

    2007-01-01

    A proper presentation of scientific discoveries may allow science teachers to eliminate certain myths about the nature of science, which originate from an uncertainty among scholars about what constitutes a discovery. It is shown that a disagreement on this matter originates from a confusion of the act of discovery with response to it. It is…

  17. Putting Science into Elementary Science Fairs.

    ERIC Educational Resources Information Center

    Russell, Helen Ross

    In a world where science has become too confined to books and too reliant on technology, and science fairs have been taken over by parents, this paper offers suggestions to help young people have actual hands-on experience with nature. Topics include soil formation; ants; earthworms; temperature; weather predictions; rain acidity; physical science…

  18. Giant Steps Through Science, Science I.

    ERIC Educational Resources Information Center

    Bertke, Mary Christopher; Feistritzer, Emily

    This text is designed for use in a first year high school science course and is an attempt to put basic physical science concepts into a logical order. This organization involves an historical approach, beginning with four chapters on astronomy: Modern Astronomy, The Ancient Astronomers, Astronomy - Ptolemy to Kepler, and Galileo and Newton. The

  19. Giant Steps Through Science, Science I.

    ERIC Educational Resources Information Center

    Bertke, Mary Christopher; Feistritzer, Emily

    This text is designed for use in a first year high school science course and is an attempt to put basic physical science concepts into a logical order. This organization involves an historical approach, beginning with four chapters on astronomy: Modern Astronomy, The Ancient Astronomers, Astronomy - Ptolemy to Kepler, and Galileo and Newton. The…

  20. Informal science education at Science City

    NASA Astrophysics Data System (ADS)

    French, April Nicole

    The presentation of chemistry within informal learning environments, specifically science museums and science centers is very sparse. This work examines learning in Kansas City's Science City's Astronaut Training Center in order to identify specific behaviors associated with visitors' perception of learning and their attitudes toward space and science to develop an effective chemistry exhibit. Grounded in social-constructivism and the Contextual Model of Learning, this work approaches learning in informal environments as resulting from social interactions constructed over time from interaction between visitors. Visitors to the Astronaut Training Center were surveyed both during their visit and a year after the visit to establish their perceptions of behavior within the exhibit and attitudes toward space and science. Observations of visitor behavior and a survey of the Science City staff were used to corroborate visitor responses. Eighty-six percent of visitors to Science City indicated they had learned from their experiences in the Astronaut Training Center. No correlation was found between this perception of learning and visitor's interactions with exhibit stations. Visitor attitudes were generally positive toward learning in informal settings and space science as it was presented in the exhibit. Visitors also felt positively toward using video game technology as learning tools. This opens opportunities to developing chemistry exhibits using video technology to lessen the waste stream produced by a full scale chemistry exhibit.

  1. Science and religion: implications for science educators

    NASA Astrophysics Data System (ADS)

    Reiss, Michael J.

    2010-03-01

    A religious perspective on life shapes how and what those with such a perspective learn in science; for some students a religious perspective can hinder learning in science. For such reasons Staver's article is to be welcomed as it proposes a new way of resolving the widely perceived discord between science and religion. Staver notes that Western thinking has traditionally postulated the existence and comprehensibility of a world that is external to and independent of human consciousness. This has led to a conception of truth, truth as correspondence, in which our knowledge corresponds to the facts in this external world. Staver rejects such a conception, preferring the conception of truth as coherence in which the links are between and among independent knowledge claims themselves rather than between a knowledge claim and reality. Staver then proposes constructivism as a vehicle potentially capable of resolving the tension between religion and science. My contention is that the resolution between science and religion that Staver proposes comes at too great a cost—both to science and to religion. Instead I defend a different version of constructivism where humans are seen as capable of generating models of reality that do provide richer and more meaningful understandings of reality, over time and with respect both to science and to religion. I argue that scientific knowledge is a subset of religious knowledge and explore the implications of this for science education in general and when teaching about evolution in particular.

  2. Meaningful Science: Teachers Doing Inquiry + Teaching Science.

    ERIC Educational Resources Information Center

    Kielborn, Terrie L., Ed.; Gilmer, Penny J., Ed.

    This publication relates the experiences of seven K-8 teachers who participated in a science education doctoral cohort group during which each of the teachers engaged in a different real-world scientific research project. The idea was to immerse teachers in scientific research so that they could experience inquiry in science first-hand and become…

  3. Science, Pseudo-Science, and Natural Theology.

    ERIC Educational Resources Information Center

    Ferre, Frederick

    1983-01-01

    Religions are unfalsifiable in the short run but open to long-term influence by science. Conversely, scientists sometimes extend their findings to mythic proportions. The struggle between evolutionary science and pseudo-scientific creationism rests on tensions resulting at this interface. Good education and social fairness require greater…

  4. Teaching Science Fact with Science Fiction

    ERIC Educational Resources Information Center

    Raham, R. Gary

    2004-01-01

    The literature of science fiction packs up the facts and discoveries of science and runs off to futures filled with both wonders and warnings. Kids love to take the journeys it offers for the thrill of the ride, but they can learn as they travel, too. This book will provide the reader with: (1) an overview of the past 500 years of scientific…

  5. Environmental Science Projects. LC Science Tracer Bullet.

    ERIC Educational Resources Information Center

    Carter, Constance, Comp.

    Sources to assist junior and senior high school students and teachers in planning, preparing, and executing science fair projects in the environmental sciences are cited in this bibliography that includes a few books with experiments suitable for elementary grade students. Information and/or citations are provided under the following headings: (1)…

  6. Environmental Science Projects. LC Science Tracer Bullet.

    ERIC Educational Resources Information Center

    Carter, Constance, Comp.

    This bibliography cites sources to assist middle, junior, and senior high school students and teachers in planning, preparing, and executing science fair projects in the environmental sciences. In addition, a few books with experiments suitable for elementary grade students are included. The listing includes: (1) 5 introductory texts; (2) 31…

  7. Beyond Science Literacy: Science and the Public

    ERIC Educational Resources Information Center

    Liu, Xiufeng

    2009-01-01

    The late 20th century and beginning of 21st century have witnessed unprecedented rapid economic development due to advances in technology and globalization. In response to this development, a renewed call for science literacy has become louder in the USA and many other countries. Common to all science education reforms around the world is emphasis

  8. Contextualized Science for Teaching Science and Technology.

    ERIC Educational Resources Information Center

    Koul, Ravinder; Dana, Thomas M.

    1997-01-01

    Discusses science education in India, arguing that a contextualized curriculum is a powerful means of improvement. The paper presents results from an analysis of the treatment of the nature of science and technology in current Indian textbooks and uses India's controversial Sadar Sarovar Hydro-Electric Project as a case example. (SM)

  9. The Des Moines Plan: A Plan for Student Success.

    ERIC Educational Resources Information Center

    Castelda, Sharon; Wagner, Mary

    The Des Moines Plan (DMP) is described, which is a comprehensive kindergarten through grade 12 program designed to improve and strengthen students' reading, writing, and mathematics skills. The program was implemented during the fall semester of the 1986-87 school year. The DMP adopted the instructional model implemented by the Chapter 1 program…

  10. Simulations of the OzDES AGN reverberation mapping project

    NASA Astrophysics Data System (ADS)

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; Denney, K. D.; Kochanek, C. S.; Peterson, Bradley M.; Skielboe, Andreas; Vestergaard, Marianne; Huff, Eric; Watson, Darach; Banerji, Manda; McMahon, Richard; Sharp, Rob; Lidman, C.

    2015-10-01

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ≥500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrain the radius-luminosity (R-L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ˜35-45 per cent of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ˜1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R-L relationship parameters for H β, Mg II λ2798, and C IV λ1549. Extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R-L parameter constraints for all broad emission lines.

  11. The ``La Vue-des-Alpes'' underground laboratory

    NASA Astrophysics Data System (ADS)

    Gonin, Yvan; Busto, José; Vuilleumier, Jean-Luc

    2003-11-01

    The measurement of the intrinsic radioactivity in a wide range of solid, liquid, and gaseous materials is very important for several activity domains, such as in particle physics experiments, medical research, environmental activity, and natural resources. Very precise measurements can be undertaken in the "La Vue-des-Alpes" Underground Laboratory. This article describes this laboratory and the measurements we have performed there.

  12. Simulations of the OzDES AGN reverberation mapping project

    SciTech Connect

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; Denney, K. D.; Kochanek, C. S.; Peterson, Bradley M.; Skielboe, Andreas; Vestergaard, Marianne; Huff, Eric; Watson, Darach; Banerji, Manda; McMahon, Richard; Sharp, Rob; Lidman, C.

    2015-08-26

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ~500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrain the radius–luminosity (R–L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ~35–45 % of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ~1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R–L relationship parameters for Hβ, MgIIλ2798, and C IVλ1549. As a result, extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R–L parameter constraints for all broad emission lines.

  13. Recognition of Langue des Signes Quebecoise in Eastern Canada

    ERIC Educational Resources Information Center

    Parisot, Anne-Marie; Rinfret, Julie

    2012-01-01

    This article presents a portrait of two community-level and legal efforts in Canada to obtain official recognition of ASL and LSQ (Langue des signes quebecoise), both of which are recognized as official languages by the Canadian Association of the Deaf (CAD). In order to situate this issue in the Canadian linguistic context, the authors first…

  14. Measurement science and manufacturing science research

    NASA Technical Reports Server (NTRS)

    Phillips, D. Howard

    1987-01-01

    The research program of Semiconductor Research Corp. is managed as three overlapping areas: Manufacturing Sciences, Design Sciences and Microstructure Sciences. A total of 40 universities are participating in the performance of over 200 research tasks. The goals and direction of Manufacturing Sciences research became more clearly focused through the efforts of the Manufacturing Sciences Committee of the SRC Technical Advisory Board (TAB). The mission of the SRC Manufacturing Research is the quantification, control, and understanding of semiconductor manufacturing process necessary to achieve a predictable and profitable product output in the competitive environment of the next decade. The 1994 integrated circuit factory must demonstrate a three level hierarchy of control: (1) operation control, (2) process control, and (3) process design. These levels of control are briefly discussed.

  15. Physical Sciences 2007 Science & Technology Highlights

    SciTech Connect

    Hazi, A U

    2008-04-07

    The Physical Sciences Directorate applies frontier physics and technology to grand challenges in national security. Our highly integrated and multidisciplinary research program involves collaborations throughout Lawrence Livermore National Laboratory, the National Nuclear Security Administration, the Department of Energy, and with academic and industrial partners. The Directorate has a budget of approximately $150 million, and a staff of approximately 350 employees. Our scientists provide expertise in condensed matter and high-pressure physics, plasma physics, high-energy-density science, fusion energy science and technology, nuclear and particle physics, accelerator physics, radiation detection, optical science, biotechnology, and astrophysics. This document highlights the outstanding research and development activities in the Physical Sciences Directorate that made news in 2007. It also summarizes the awards and recognition received by members of the Directorate in 2007.

  16. L'Infection Nosocomiale en Reanimation des Brules

    PubMed Central

    Siah, S.; Belefqih, R.; Elouennass, M.; Fouadi, F.E.; Ihrai, I.

    2009-01-01

    Summary L'infection nosocomiale bactérienne étant l'une des principales causes de morbidité et de mortalité chez le brûlé, nous avons réalisé une étude rétrospective portant sur 84 patients hospitalisés au sein du service de réanimation des brûlés de l'Hôpital Militaire d'Instruction Mohammed V de Rabat, sur une période de 3 ans, du premier janvier 2001 au 31 décembre 2003. Les critères d'infection nosocomiale étaient ceux du Center for Disease Control d'Atlanta de 1988. Les taux d'incidence ont été calculés. La population infectée a été comparée à celle non infectée. L'écologie bactérienne du service a été décrite comme aussi l'antibiotype. Il ressort de cette étude la survenue de 87 infections nosocomiales chez 27 patients. L'incidence cumulative était de 103 infections pour 1000 jours de traitement. Pour ce qui est des caractéristiques des infections bactériennes, les sites infectés étaient la peau (77%), le sang (13,8%), les voies urinaires (8%) et les poumons (1,1%). Les principaux germes étaient: Staphylococcus sp. (33,3%), Pseudomonas aeruginosa (23%), Enterococcus faecalis et Acinetobacter (8%). Les staphylocoques étaient méticillo-résistants dans 22,2% des cas. Le Pseudomonas et l'Acinetobacter étaient multirésistants (60%). Dans notre étude les facteurs prédictifs de survenue des infections nosocomiales que nous avons retenus après l'étude comparative des populations infectées et non infectées ont été l'âge, le body mass index, l'abbreviated burn severity index et le remplissage initial. En isolant ces paramètres, nous avons pu établir une équation à valeur prédictive de survenue d'infection nosocomiale chez le patient brûlé. PMID:21991158

  17. La biogenèse des mélanosomes

    PubMed Central

    Delevoye, Cédric; Giordano, Francesca; van Niel, Guillaume; Raposo, Graça

    2012-01-01

    Les mélanocytes situés à la base de l’épiderme produisent des mélanosomes qui sont transférés aux kératinocytes pour assurer la pigmentation de l’épiderme et sa photoprotection contre les rayons ultraviolets. Les mélanosomes, organites apparentés aux lysosomes, sont le lieu de synthèse et de stockage d’un pigment, la mélanine. Leur formation dépend de protéines mélanosomales qui transitent par les voies de biosynthèse et d’endocytose et exploitent les mécanismes moléculaires du trafic intracellulaire. Les acteurs moléculaires impliqués dans le transport des protéines mélanosomales et la biogenèse des mélanosomes sont la cible de mutations dans des maladies génétiques accompagnées d’hypopigmentation comme l’albinisme et les maladies lysosomales. Les études menées sur les mélanocytes issus de souris modèles de ces maladies permettent de comprendre certaines des étapes-clés de la mélanogenèse ainsi que les dysfonctionnements associés à ces pathologies. De plus, décrypter la mélanogenèse facilite également la compréhension d’autres processus physiologiques, comme l’illustrent les similitudes inattendues avec l’amyloïdogenèse dans les maladies neurodégénératives. PMID:21382323

  18. "Science Is Sick."

    ERIC Educational Resources Information Center

    Turner, Peter M.

    1979-01-01

    Intends to show that there is something rotten in the state of education generally and particularly in that of the sciences. The author contends that science pedagogues should lead the current research and development of new ideas. (HM)

  19. Collaboration and Team Science

    Cancer.gov

    A Template for Integrating Interdisciplinary Research and Team Science into the Tenure Track Offer Letter Although every recruitment is unique, emphasis on interdisciplinary and multidisciplinary science is becoming quite common. Research institutions wan

  20. Reading About Science Communication

    NASA Astrophysics Data System (ADS)

    Russo, P.

    2010-06-01

    Lately the science communication book market has become quite lively. Several books have been published over the past few years. Covering topics from more formal science communication to practical writing, these books are important resources for everyone.

  1. An Alternative Science Fair.

    ERIC Educational Resources Information Center

    Romjue, Mary Kalen; Clementson, John J.

    1992-01-01

    Proposes the organization of noncompetitive science fairs to create a more positive learning experience for children in the elementary grades. Describes methods of organizing and judging the fair, and provides a list of suggested resources for science fair projects. (MDH)

  2. Lunar & Planetary Science Conference.

    ERIC Educational Resources Information Center

    Warner, Jeffrey L.; And Others

    1982-01-01

    Summaries of different topics discussed at the Lunar and Planetary Science Conference are presented to provide updated information to nonplanetologists. Some topics include Venus, isotopes, chondrites, creation science, cosmic dust, cratering, moons and rings, igneous rocks, and lunar soil. (DC)

  3. Bag It for Science!

    ERIC Educational Resources Information Center

    Carlile, Candy

    1992-01-01

    Describes enrichment activities in which students read selections from science trade books and perform hands-on science activities related to the readings. Suggests four readings and related activities involving trees, robots, spiders, and birds. (Contains 13 references.) (MDH)

  4. Science in General Education

    ERIC Educational Resources Information Center

    Read, Andrew F.

    2013-01-01

    General education must develop in students an appreciation of the power of science, how it works, why it is an effective knowledge generation tool, and what it can deliver. Knowing what science has discovered is desirable but less important.

  5. Integrating Forensic Science.

    ERIC Educational Resources Information Center

    Funkhouser, John; Deslich, Barbara J.

    2000-01-01

    Explains the implementation of forensic science in an integrated curriculum and discusses the advantages of this approach. Lists the forensic science course syllabi studied in three high schools. Discusses the unit on polymers in detail. (YDS)

  6. ICASE Computer Science Program

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The Institute for Computer Applications in Science and Engineering computer science program is discussed in outline form. Information is given on such topics as problem decomposition, algorithm development, programming languages, and parallel architectures.

  7. The Science of Patterns.

    ERIC Educational Resources Information Center

    Steen, Lynn Arthur

    1988-01-01

    Discusses the changing nature of mathematics. Describes how computers, applications, and cross-fertilization have produced new methods, theories, and models in the mathematical sciences transforming it into a powerful collection of tools for science. (RT)

  8. National Academy of Sciences

    MedlinePlus

    ... Read More » Proceedings of the National Academy of Sciences (PNAS) PNAS is one of the world’s most- ... Exchange Evolution Resources Biographical Memoirs National Academy of Sciences About The NAS Mission History Organization Leadership and ...

  9. Earth Science Programs

    NASA Technical Reports Server (NTRS)

    Freeman, Tony; Im, Eastwood

    2007-01-01

    This slide presentation reviews the JPL missions that enabling Earth Sciences, past, present and future. Included is a list of the National Academy of Sciences Space Studies Board of the recommended missions that are of interest to JPL.

  10. AAAS: Politics. . . and Science

    ERIC Educational Resources Information Center

    Science News, 1978

    1978-01-01

    Reviews topics discussed during the American Association for the Advancement of Science (AAAS) meeting held in Washington, D.C. Topics included: the equal rights amendment, laetrile, nuclear radiation hazards, sociobiology, and various science topics. (SL)

  11. Inequalities in Science

    PubMed Central

    Xie, Y.

    2014-01-01

    Inequalities in scientists’ contributions to science and their rewards have always been very high. There are good reasons to propose that inequalities in science across research institutions and across individual scientists have increased in recent years. In the meantime, however, globalization and internet technology have narrowed inequalities in science across nations and facilitated the expansion of science and rapid production of scientific discoveries through international collaborative networks. PMID:24855244

  12. Science Fair Art

    ERIC Educational Resources Information Center

    Sullivan, Kevin

    2004-01-01

    Sciences fair season is a time when seasoned non-science teachers typically give up all hope of cramming any more knowledge into the heads of their students. It's just too much. However, non-science types might be missing out on a pretty good deal. The science department has got these kids in a pretty tight grip as far as the process and the…

  13. Croissance des couches minces et des multicouches de matériaux supraconducteurs H Tboldmath_c : bilan et perspective

    NASA Astrophysics Data System (ADS)

    Contour, J. P.

    1994-11-01

    The main physical and chemical techniques of epitaxial growth of High T_c superconductor thin films are described together with their in situ analysis facilities and discussed with respect to their cost, sophistication and results (T_c, J_c growth defects, thickness and composition uniformity, crystallinity, electronic applications...). The future trends of the growth machines are then examined in connection with the present results and the development of superconductor electronics. Après la présentation des principales techniques de croissance physique et physicochimique de couches minces d'oxydes supraconducteurs à haute température critique, un bilan des résultats sera dressé par rapport aux différentes propriétés des films (transition résistive, courant critique, défauts de croissance, uniformité d'épaisseur et de composition, cristallinité...), aux difficultés de mise en œuvre et au coût de l'expérience. Les perspectives des différentes techniques seront ensuite examinées dans le cadre du développement potentiel d'une électronique utilisant les matériaux supraconducteurs H T_c.

  14. Optimisation des proprietes fonctionnelles des alliages a memoire de forme suite a l'application de traitements thermomecaniques

    NASA Astrophysics Data System (ADS)

    Demers, Vincent

    L'objectif de ce projet est de determiner les conditions de laminage et la temperature de traitement thermique maximisant les proprietes fonctionnelles de l'alliage a memoire de forme Ti-Ni. Les specimens sont caracterises par des mesures de calorimetrie, de microscopie optique, de gene ration de contrainte, de deformation recuperable et des essais mecaniques. Pour un cycle unique, l'utilisation d'un taux d'ecrouissage e=1.5 obtenu avec l'application d'une force de tension FT = 0.1sigma y et d'une huile minerale resulte en un echantillon droit, sans microfissure et qui apres un recuit a 400°C, produit un materiau nanostructure manifestant des proprietes fonctionnelles deux fois plus grandes que le meme materiau ayant une structure polygonisee. Pour des cycles repetes, les memes conditions de laminage sont valables mais le niveau de deformation optimal est situe entre e=0.75-2, et depend particulierement du mode de sollicitation, du niveau de stabilisation et du nombre de cycles a la rupture requis par l'application.

  15. Analyse des possibilités de fonctionnement en régime des désexcitation des moteurs à aimants permanents

    NASA Astrophysics Data System (ADS)

    Multon, Bernard; Lucidarme, Jean; Prévond, Laurent

    1995-05-01

    In this paper, we study the extending of speed range of motors (or generators) with permanent magnet inductor and supplied by electronic converter. The amplitude of phase voltage and current waveforms are limited by electronics supply. The aim of this study is to achieve a maximum power near of the base speed one on an extended speed range. This require an airgap flux weakening so called “flux weakening” above base speed. A parametric analysis of motor electromagnetic characteristics is made to show the influence of armature reaction and magnetic saliency on speed range. We show that exists an ideal condition to obtain a constant power speed range theoretically unlimited. Magnetic saliency permits to enhance the power factor especially when L_d> L_q. As main hypotheses, we consider no saturation, e.m.f. and current sine waveforms and a sinusoidal airgap flux density. Finally, we recapitulate the permanent magnet rotor structures able to obtain a flux-weakening operation. Cet article traite de l'extension de la plage de vitesse des moteurs (ou alternateurs) à excitation par aimants permanents et alimentés par convertisseur électronique. La tension et le courant sont limités en amplitude par l'alimentation électronique.L'objectif est d'obtenir une puissance proche de celle correspondant au régime de base sur une plage de vitesse étendue. Ceci nécessite une réduction de flux d'entrefer ou “désexition” au delà de la vitesse de base. Une analyse paramétrique des caractéristiques du moteur est effectuée pour mettre en évidence l'influence de la réaction d'induit et de la saillance magnétique. Nous montrons qu'il existe une condition idéale pour obtenir une plage de fonctionnement à puissance constante théoriquement illimitée. La saillance magnétique permet d'accroître le facteur de puissance surtout lorsque L_d> L_q. Les principales hypothèses de cette étude sont l'absence de saturation, des f.e.m. et des courants sinusoïdaux et une induction spatiale sinusoïdale dans l'entrefer. Enfin, nous effectuons un bilan des structures de rotors permettant un fonctionnement en régime de désexcitation.

  16. Lignes directrices canadiennes sur l’utilisation sécuritaire et efficace des opioïdes pour la douleur chronique non cancéreuse

    PubMed Central

    Kahan, Meldon; Wilson, Lynn; Mailis-Gagnon, Angela; Srivastava, Anita

    2011-01-01

    Résumé Objectif Présenter aux médecins de famille un résumé clinique pratique sur la prescription d’opioïdes à des populations particulières en se fondant sur les recommandations faites dans les lignes directrices canadiennes sur l’utilisation sécuritaire et efficace des opioïdes pour la douleur chronique non cancéreuse. Qualité des données Pour produire les lignes directrices, les chercheurs ont effectué une synthèse critique de la littérature médicale en insistant plus précisément sur les études de l’efficacité et de la sécurité des opioïdes dans des populations particulières. Message principal Les médecins de famille peuvent atténuer les risques de surdose, de sédation, d’usage abusif et de dépendance grâce à des stratégies adaptées à l’âge et à l’état de santé des patients. Dans le cas de patients à risque de dépendance, on devrait réserver les opioïdes aux douleurs nociceptives ou neuropathiques bien définies qui n’ont pas répondu aux traitements de première intention. Il faut procéder lentement au titrage des opioïdes, avec des dispensations fréquentes et une étroite surveillance pour dépister tout signe d’usage abusif. Une dépendance aux opioïdes suspectée est prise en charge au moyen d’une thérapie structurée aux opioïdes, d’un traitement à la méthadone ou à la buprénorphine ou encore d’un traitement fondé sur l’abstinence. Les patients souffrant de troubles de l’humeur ou d’anxiété ont tendance à avoir une réponse analgésique atténuée aux opioïdes, sont à risque plus élevé d’usage abusif et prennent souvent des sédatifs qui interagissent défavorablement avec les opioïdes. Il faut prendre des précautions semblables à celles utilisées avec d’autres patients à risque élevé. Il faut faire un sevrage progressif si la douleur du patient demeure sévère même avec un essai adéquat de thérapie aux opioïdes. Chez les personnes âgées, la sédation, les chutes et la surdose peuvent être minimisées en utilisant des doses initiales faibles, un titrage plus lent, un sevrage des benzodiazépines et une bonne éducation des patients. Dans le cas des femmes enceintes qui prennent des opioïdes chaque jour, il faut faire un sevrage progressif et cesser complètement. Si ce n’est pas possible, il faut administrer la dose efficace la plus faible. Les femmes enceintes qui ont une dépendance aux opioïdes devraient recevoir un traitement à la méthadone. Les adolescents sont à risque élevé de surdose d’opioïdes, d’usage abusif et de dépendance. Les patients qui ont des adolescents qui vivent à la maison devraient entreposer leurs opioïdes dans un lieu sûr. Les adolescents ont rarement besoin d’une thérapie à long terme aux opioïdes. Conclusion Les médecins de famille doivent tenir compte de l’âge, de la condition psychiatrique, du degré de risque de dépendance du patient et d’autres facteurs quand ils prescrivent des opioïdes pour la douleur chronique.

  17. Les reseaux de politique publique comme facteur d'influence du choix des instruments de politique energetique canadienne a des fins environnementales de 1993 a nos jours

    NASA Astrophysics Data System (ADS)

    Fathy El Dessouky, Naglaa

    Au cours de la derniere decennie, les modes de la gouvernance ont pris place dans un contexte totalement different de celui qu'ils avaient auparavant. Les gouvernements modernes se rendent compte qu'ils perdent de plus en plus leur capacite a elaborer et a gerer les changements d'une maniere autonome. Ainsi, les fonctions et les activites traditionnellement accomplies exclusivement par le gouvernement engagent de nos jours une gamme d'acteurs etatiques et non etatiques. A l'encontre du concept traditionnel de l'Etat controleur, la gouvernance contemporaine est ainsi devenue moins une question d'offre de service et davantage une gestion indirecte des reseaux de politique publique. Dans cette entreprise, les gouvernements contemporains, cherchant plus d'information, de soutien et de legitimite en matiere de formulation des decisions, ont besoin d'etablir des relations avec les divers groupes d'interet qui, a leur tour, voulaient plus de promotion et de protection en faveur de leurs interets a travers leur implication au processus de l'elaboration et de la mise en oeuvre des politiques publiques. Ainsi, l'approche des reseaux de politique publique represente aujourd'hui un courant considerable au sein du champ d'analyse des politiques publiques. Toutefois, les preoccupations des chercheurs pour cette approche, dans le domaine des politiques energetiques a des fins environnementales, semblent recentes, et les etudes realisees sont encore trop peu nombreuses. Au Canada, au debut des annees 1990, le gouvernement ainsi que plusieurs groupes d'interets, des differents secteurs energetique, industriel et environnemental, ont commence a intensifier leurs efforts pour s'attaquer au probleme du changement climatique d'origine energetique, genere surtout par le secteur de l'industrie. Au cours de la derniere decennie, la question touchant plutot le sujet du developpement energetique durable represente le plus important domaine des politiques publiques ayant surgi recemment dans l'agenda politique du pays. Notre projet de recherche, par le truchement de l'approche des reseaux de politique publique, s'attarde a decrire et a expliquer le processus de la formulation d'une politique particuliere, soit la politique energetique a des fins de protection de l'environnement, elaboree en 1993. Il s'agit de mettre en evidence les facteurs affectant le choix des instruments de ces politiques publiques dans leur contexte national. Ainsi, la question generale de cette recherche est: Comment les phases evolutives de la formation d'un reseau de politique, en l'occurrence le Conseil canadien de l'energie (CCE), menent a des caracteristiques particulieres a ce reseau; et comment celles-ci determinent-elles les types des instruments de politique publique choisis, particulierement ceux de la recente orientation des politiques energetiques canadiennes a des fins environnementales elaborees en 1993? Afin d'atteindre l'objectif de notre recherche, deux facteurs primordiaux sont utilises, soit la circulation de l'information et l'exercice du controle sur les ressources des acteurs. L'analyse des caracteristiques du reseau en fonction des liens forts et des liens faibles autant que la presence ou l'absence des trous structuraux nous permettent de bien identifier les positions des differents acteurs, etatiques et non etatiques, sur le plan de l'information et du controle, qui a leur tour, nous semble-t-il, constituent des facteurs affectant les types des instruments des politiques publiques choisis: instruments substantifs, qui indiquent le degre de l'intervention du gouvernement, et instruments proceduraux, qui mettent plutot l'accent sur le degre de l'influence du gouvernement sur les acteurs non etatiques. L'etude soutient que l'approche des reseaux se distingue notamment par son potentiel a expliquer l'interrelation relative entre idees, interets et institutions, ce qui a son tour est susceptible de permettre une meilleure comprehension des processus de l'elaboration des politiques energetiques et environnementales canadiennes. Qui plus est, le fait de recourir a ce cadre d'analyse permet d'approcher autrement le sujet etudie en essayant de comprendre et d'expliquer non seulement les interactions entre les differents acteurs cibles, mais aussi le dynamisme et l'evolution de ces relations dans leur duree, comme etant des determinants primordiaux en matiere de selection des instruments des politiques.

  18. The Open Science Grid status and architecture

    SciTech Connect

    Pordes, Ruth; Petravick, Don; Kramer, Bill; Olsen, James D.; Livny, Miron; Roy, Gordon A.; Avery, Paul Ralph; Blackburn, Kent; Wenaus, Torre J.; Wuerthwein, Frank K.; Foster, Ian; /Chicago U. /Indiana U.

    2007-09-01

    The Open Science Grid (OSG) provides a distributed facility where the Consortium members provide guaranteed and opportunistic access to shared computing and storage resources. The OSG project[1] is funded by the National Science Foundation and the Department of Energy Scientific Discovery through Advanced Computing program. The OSG project provides specific activities for the operation and evolution of the common infrastructure. The US ATLAS and US CMS collaborations contribute to and depend on OSG as the US infrastructure contributing to the World Wide LHC Computing Grid on which the LHC experiments distribute and analyze their data. Other stakeholders include the STAR RHIC experiment, the Laser Interferometer Gravitational-Wave Observatory (LIGO), the Dark Energy Survey (DES) and several Fermilab Tevatron experiments- CDF, D0, MiniBoone etc. The OSG implementation architecture brings a pragmatic approach to enabling vertically integrated community specific distributed systems over a common horizontal set of shared resources and services. More information can be found at the OSG web site: www.opensciencegrid.org.

  19. The Open Science Grid status and architecture

    NASA Astrophysics Data System (ADS)

    Pordes, R.; Petravick, D.; Kramer, B.; Olson, D.; Livny, M.; Roy, A.; Avery, P.; Blackburn, K.; Wenaus, T.; Würthwein, F.; Foster, I.; Gardner, R.; Wilde, M.; Blatecky, A.; McGee, J.; Quick, R.

    2008-07-01

    The Open Science Grid (OSG) provides a distributed facility where the Consortium members provide guaranteed and opportunistic access to shared computing and storage resources. The OSG project[1] is funded by the National Science Foundation and the Department of Energy Scientific Discovery through Advanced Computing program. The OSG project provides specific activities for the operation and evolution of the common infrastructure. The US ATLAS and US CMS collaborations contribute to and depend on OSG as the US infrastructure contributing to the World Wide LHC Computing Grid on which the LHC experiments distribute and analyze their data. Other stakeholders include the STAR RHIC experiment, the Laser Interferometer Gravitational-Wave Observatory (LIGO), the Dark Energy Survey (DES) and several Fermilab Tevatron experiments- CDF, D0, MiniBoone etc. The OSG implementation architecture brings a pragmatic approach to enabling vertically integrated community specific distributed systems over a common horizontal set of shared resources and services. More information can be found at the OSG web site: www.opensciencegrid.org.

  20. Perception of the A/H1N1 influenza pandemic and acceptance of influenza vaccination by Université Claude Bernard Lyon 1 staff: A descriptive study

    PubMed Central

    Amour, Sélilah; Djhehiche, Khaled; Zamora, Adeline; Bergeret, Alain; Vanhems, Philippe

    2015-01-01

    We assessed the perception and attitudes of university staff, including medical school and other science specialties, toward the 2009 A/H1N1 influenza pandemic and influenza vaccination program. A cross-sectional online survey was conducted among 4,529 university personnel on October 19–20, 2009. Seven hundred (15%) employees participated in the study. Only 18% were willing to be vaccinated, men more than women (29% versus 9%, P < 0.001), and professors/researchers more than administrative/technical staff (30% vs. 6%, P < 0.001). Intention to be vaccinated was insufficient. Additional efforts are needed to improve information dissemination among university staff. Medical university personnel should receive more information to increase vaccine coverage and protect them as well as patients. PMID:25715115