335 research outputs found
Minority Parents and School Choice: A Multiple Case Study
Low levels of academic achievement among minority students in U.S. schools continues to be problematic. Although school choice, via enrollment in public charter or private schools, is one strategy that may improve academic achievement among minorities, little is known about how parents of minority students understand and exercise school choice. The purpose of this multiple case study was to explore understandings of school choice among parents with students enrolled in three types of schools: (a) public charter, (b) private, and (c) traditional public. The framework consisted of three theories: bounded rationality, the economic theory of school choice, and critical race theory. Data were collected via three focus groups with parents from three types of schools. . Through axial coding, a total of seven themes were identified, including definitions of school choice provided by minority parents, social perceptions of school choice, economic perceptions of school choice are negative, strategies used to access information, factors in parentsâ school choice decisions, school choice information is inaccessible or unavailable, and parents should be informed of school choice. Eleven subthemes emerged, including parents unfamiliar with school choice, school choice describes options for parents and students, tools available for school choice, positive perceptions, negative perceptions, networking, proactive research, financial factors, student-level factors, parent preference factors, and school-level factors. While school choice has the potential to improve academic outcomes for minority students, the current research highlighted challenges in parentâs decision-making processes that may undermine the potential of school choice to improve educational equity
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Forging New Roads: Expanding the Theatrical Touring Market Internationally
A discussion examining current practices on Broadway and around the world to recommend a set of ides and criteria for producing commercial theatre internationally. This includes sections on the current Broadway climate, the various types of theatrical markets, producing in the UK and Australia, past practices from productions that have traveled abroad, recommendations for a new model of international producing, and new developments that will contribute to the future of international producing
Monumentalisation en Bosnie-Herzégovine d'aprÚs-guerre : réconciliation et prise de parole
Tableau d'honneur de la FacultĂ© des Ă©tudes supĂ©rieures et postdoctorales, 2010-2011Les monuments constituent des lieux oĂč se cristallisent certaines visions du passĂ©, du prĂ©sent et de l'avenir. Ce mĂ©moire aborde la question de la monumentalisation en Bosnie-HerzĂ©govine en contexte d'aprĂšs-guerre (1995-2007). Ă travers des exemples choisis de monuments construits ou en voie de l'ĂȘtre, l'auteure met en lumiĂšre les choix politiques qui motivent la mise en monument d'Ă©vĂ©nements, de personnages ou d'idĂ©es. L'objectif est de saisir quel modĂšle social est promu Ă travers ces monuments. Les notions de mĂ©moire, de nation et de citoyennetĂ© sont mobilisĂ©es afin de comprendre la volontĂ© politique qui soutient la construction de monuments en Bosnie-HerzĂ©govine. Plus prĂ©cisĂ©ment, ce mĂ©moire montre comment la monumentalisation du souvenir, de l'exemple et de la prise de parole vise Ă contrer les nationalismes et Ă promouvoir la rĂ©conciliation du pays. La construction de monuments en Bosnie-HerzĂ©govine laisse de plus entrevoir une nouvelle forme de solidaritĂ© en Ă©mergence
Caractérisation des lymphopénies post-chirurgies cardiaques de type Fontan
La thymectomie est un geste chirurgical fréquemment nécessaire lors des interventions cardiaques en période néonatale. Il est connu que la résection du thymus entraßne une lymphopénie ne semblant pas avoir de conséquences cliniques graves. La lymphopénie constatée serait plus importante chez les patients ayant eu une chirurgie cardiaque de type Fontan. Toutefois, on ignore si la lymphopénie est uniquement secondaire à la thymectomie ou si elle est liée à ce type particulier de chirurgie cardiaque.
La présente recherche porte sur 19 patients opérés selon l'approche Fontan; ils ont été comparés à 6 patients "contrÎle" ayant eu une thymectomie au cours d'une chirurgie cardiaque d'un autre type. Les résultats indiquent que les patients de type Fontan accusent une diminution du nombre de cellules naïves CD4+ et CD8+ et plus particuliÚrement une baisse de leurs émigrants thymiques (CD45RA+CD31+/CD4+). On note en contrepartie une expansion du répertoire mémoire (CD45RO+). Ces altérations lymphocytaires sont comparables aux contrÎles.
Il semble donc que les anomalies lymphocytaires relevées soient reliées principalement à la thymectomie et non pas au type de chirurgie. Les infections plus importantes chez les Fontan, quant à elles, pourraient s'expliquer par une évolution post-opératoire défavorable.The thymectomy is a surgical procedure often done during cardiac surgery. It is well known that the resection of the thymus can cause alterations of lymphocyte subpopulations without major clinical consequences. This lymphopenia could be more pronounced in patients who undergone a cardiac surgery named "Fontan". Nevertheless, it is not known if these alterations are due to the thymectomy or this specific type of cardiac surgery.
We recruited 19 patients with Fontan surgery and compared them to 6 patients who had a cardiac surgery of another type. Our results show decreased CD4+ and CD8+ naive T cells populations and more specifically, low numbers of thymic emigrants (CD45RA+CD31+/CD4+). Expansion of memory repertoire (CD45RO+) is also noted. These findings are also found in the control group.
Thus, perturbations of T cells populations seem to be related to the thymectomy rather than the type of cardiac surgery. Infections were more severe in the Fontan group but they can be explained by an unfavourable post-operative evolution in this group of patients
Application d'une méthode d'électrophorÚse pour la caractérisation et la reconnaissance des porte-greffe
L'Ă©tude par Ă©lectrophorĂšse (gel d'amidon) de la glucose-phosphate-isomĂ©rase (GPI, EC 5.3.1.9) sur des extraits obtenus Ă partir des jeunes racines ou de sarments aoĂ»tes a montrĂ© que ce type de matĂ©riel vĂ©gĂ©tal pouvait ĂȘtre utilise en vue de l'identification des porte-greffe. Pour les racines, les meilleurs rĂ©sultats ont Ă©tĂ© obtenus Ă partir de plants dont le feuillage Ă©tait en bon Ă©tat et en dĂ©but de phase de croissance. L'utilisation de sarments s'est rĂ©velĂ©e en dĂ©finitive plus facile et plus intĂ©ressante au niveau de la realisation des extraits et de la nettetĂ© des sĂ©parations. La variabilitĂ© observĂ©e pour le systĂšme enzymatique GPI-2 sur les trente porte-greffe autorisĂ©s en France s'avĂšre interĂ©ssante dans une optique taxonomique et la stabilitĂ© des rĂ©sultats a Ă©tĂ© confirmĂ©e. Neuf phĂ©notypes diffĂ©rents (dont trois non signales jusqu'Ă prĂ©sent) ont Ă©tĂ© mis en Ă©vidence permettant de caractĂ©riser et de reconnaĂźtre cinq porte-greffe (Fercal, .41 B, 333 E.M., 161-49 C, Vialla) et de rĂ©partir les autres en quatre groupes. L'Ă©tude d'un systĂšme complĂ©mentaire au moins devra ĂȘtre envisagĂ©e pour pouvoir sĂ©parer l'ensemble de ces porte-greffe.Utilization of isozyme analysis to the characterization and the identification of rootstocksIsozyme analysis by starch gel electrophoresis for glucose phosphate isomerase (GPI, EC 5.3.1.9) from roots and woody canes extracts showed that this material can be used for identification of the rootstocks. Concerning the roots the best results were obtained at the first stage of growth (during spring) when the plants were in good physiological state but this material is rather delicate. It is easier and more interesting to work with extracts of scrapings from woody canes which give good results and fair resolutions. The variability of the GPI-2 system is interesting for taxonomy and the stability of the results has been confirmed. Nine phenotypes have been found with the thirty rootstocks tested. It is possible to characterize Fercal, 41 B, 333 E.M., 161-49 C, and Vialla. The other rootstocks can be sorted in four groups. Analysis of a complementary enzyme system at least will be necessary to characterize all these rootstocks
Usefulness of two SCAR markers for marker-assisted selection of seedless grapevine cultivars
A PCR-specific marker, SCP18, was developed from a RAPD marker linked to a major locus involved in seedlessness, sdI. A preliminary study of the usefulness of SCP18 and SCC8 (a marker linked to sdI previously developed by LAHOGUE et al. 1998) for the marker assisted selection of seedless varieties was realized using various strategies: a posteriori test in seedless x seedless and seeded x seeded progenies and test of their allelic diversity in a set of 81 seedless and seeded varieties. In contrast to SCP18, SSC8 was found to be a useful marker at least in the seedless x seedless progenies and to show a good linkage disequilibrium with seedlessness in our set of varieties
Parentage of grapevine rootstock âFercalâ finally elucidated
Using a set of 20 microsatellite markers, âB.C. n°1Bâ (mother) and â31 Richterâ (father) were demonstrated to be the true parents of âFercalâ rootstock. â333 Ecole de Montpellierâ was definitively excluded as the putative father. âB.C. n°1Aâ and âB.C. n°1Bâ were shown to be distinct genotypes. âUgni blancâ, and not âColombardâ, was discovered to be the Vitis vinifera father of âB.C. n°1Bâ.
Identification of mildew resistance in wild and cultivated Central Asian grape germplasm
BACKGROUND: Cultivated grapevines, Vitis vinifera subsp. sativa, evolved from their wild relative, V. vinifera subsp. sylvestris. They were domesticated in Central Asia in the absence of the powdery mildew fungus, Erysiphe necator, which is thought to have originated in North America. However, powdery mildew resistance has previously been discovered in two Central Asian cultivars and in Chinese Vitis species. RESULTS: A set of 380 unique genotypes were evaluated with data generated from 34 simple sequence repeat (SSR) markers. The set included 306 V. vinifera cultivars, 40 accessions of V. vinifera subsp. sylvestris, and 34 accessions of Vitis species from northern Pakistan, Afghanistan and China. Based on the presence of four SSR alleles previously identified as linked to the powdery mildew resistance locus, Ren1, 10 new mildew resistant genotypes were identified in the test set: eight were V. vinifera cultivars and two were V. vinifera subsp. sylvestris based on flower and seed morphology. Sequence comparison of a 620 bp region that includes the Ren1-linked allele (143 bp) of the co-segregating SSR marker SC8-0071-014, revealed that the ten newly identified genotypes have sequences that are essentially identical to the previously identified mildew resistant V. vinifera cultivars: âKishmish vatkanaâ and âKaradzhandalâ. Kinship analysis determined that three of the newly identified powdery mildew resistant accessions had a relationship with âKishmish vatkanaâ and âKaradzhandalâ, and that six were not related to any other accession in this study set. Clustering procedures assigned accessions into three groups: 1) Chinese species; 2) a mixed group of cultivated and wild V. vinifera; and 3) table grape cultivars, including nine of the powdery mildew resistant accessions. Gene flow was detected among the groups. CONCLUSIONS: This study provides evidence that powdery mildew resistance is present in V. vinifera subsp. sylvestris, the dioecious wild progenitor of the cultivated grape. Four first-degree parent progeny relationships were discovered among the hermaphroditic powdery mildew resistant cultivars, supporting the existence of intentional grape breeding efforts. Although several Chinese grape species are resistant to powdery mildew, no direct genetic link to the resistance found in V. vinifera could be established
Distribution des principaux caractÚres phénologiques, agronomiques et technologiques chez Vitis vinifera L.
Dans la collection de vignes du Domaine de Vassal (INRA, France), l'espĂšce Vitis vinifera L. est reprĂ©sentĂ©e par 5311 introductions, soit 2236 cĂ©pages rĂ©pertoriĂ©s et 1090 introductions en cours d'Ă©tude.AprĂšs description et identification, le potentiel viticole des cĂ©pages est Ă©valuĂ©. Ces donnĂ©es, recueillies depuis plus de 40 ans, sont maintenant rassemblees dans une banque de donnĂ©es informatisĂ©e. Il est ainsi possible de calculer la rĂ©partition des principaux caractĂšres sur un grand nombre de cĂ©pages (2236). Les gĂ©notypes analysĂ©s Ă©tant d'origines trĂ©s diverses, on peut considĂ©rer cet Ă©chantillon comme une des meilleures reprĂ©sentations disponibles de Vitis vinifera L.Les distributions, moyennes, valeurs modales et extrĂȘmes sont prĂ©sentĂ©es pour les caractĂšres suivants: dates de dĂ©bourrement et de maturitĂ©, port et fertilitĂ©, poids moyen des baies et des grappes. La connaissance de la rĂ©partition de ces caractĂšres est trĂšs utile pour estimer la potentialitĂ© des semis , dĂ©terminer les cĂ©pages "extrĂȘmes" susceptibles d'ĂȘtre utilisĂ©s dans des programmes d'amĂ©lioration et mieux apprĂ©cier Vitis vinifera L.Distribution of the main phenological, agronomical and technical characters of Vitis vinifera L.In the grapevine collection of the ''Domaine de Vassal'' (INRA, France) 5311 accessions belong to Vitis vinifera L. That represents 2236 varieties and 1090 accessions which are still in process of being studied. After being described and identified, the viticultural performances of the varieties are evaluated. These data have been collected since 40 years and are now registred and joined together in a computerized data bank. So, it is possible to calculate distributions and repartitions for the most important characters of a great number of varieties (2236). The origins of these varieties are very diversified and therefore this large sample can be considered like one of the best available representations of Vitis vinifera L. The distribution, average, modal, minimum and maximum values of the following characters are presented: date of budburst, date of maturity, shoot habit, fertility, mean berry weight and mean bunch weight. The knowledge of the repartition of these characters is very useful to estimate the potentiality of seedlings and to determine the ''extreme'' varieties which could be used in different programs of grape improvement. It supplies also a contribution to a better knowledge of Vitis vinifera L
Genetic clustering and parentage analysis of Western Balkan grapevines (Vitis vinifera L.)
A total of 90 grapevine samples collected in five countries of the Western Balkan region were evaluated for trueness-to-type and kinship relations based on comparative analysis with 1,130 grapevine genotypes held at the INRA "Domaine de Vassal" French Grape Germplasm Repository, using 14 microsatellite markers. In the context of the comparative analysis, twenty-four synonyms/counterparts and the putative parents for twelve Balkan accessions were identified. We discovered five pairs of homonyms, subsequently confirming the identity or parentage of three of them. Some of the examined accessions were identified either on the basis of the genotypes found in the literature, or through parentage relationships revealed in this study. For the remaining fifty accessions we were unable to establish either their pedigree or to identify them on the basis of SSR profiles available elsewhere. Finally, the Balkan genotypes that were not well classified by synonymy or parentage analysis were further studied with a Principal Coordinate Analysis to reveal genetic clustering within larger datasets of genotypes. The graphical display of the individual and group distances showed that about forty accessions (85 %) are structured within a group of Balkan and Eastern Europe genotypes and only a minor proportion resulted in admixed population assignment
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