bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of international schools on the perception of local students’ individual and collective identities, career aspirations and choice of university
Authors: Kanan Hana M. , Baker Ahmad M. 
Published: December 2006

English This article examines the influence international schools have on adolescent local students in terms of individual and collective identity, career aspiration, and type and location of the university they wish to attend. A random cluster sample of 270 students attending international, magnet and public schools in Qatar were administered a questionnaire designed to tap their perceived identities and professional and educational aspirations. The results of the study showed that students attending international schools differed from their counterparts who attend public or magnet schools in the way they perceived themselves and their career choices. The results are discussed in terms of their relevance to future research and the influence international education may have on local students. French Cette étude a été menée pour examiner l'influence des établissements internationaux sur les élèves adolescents d'une région en termes d'identité individuelle et collective, d'aspirations professionnelles, et de type d'universités qu'ils souhaitent intégrer et leur localisation. Suite à un échantillonnage aléatoire réalisé dans des établissements internationaux, d'enseignement spécialisé et publics au Qatar, 270 élèves ont reçu un questionnaire destiné à sonder la manière dont ils perçoivent leur identité ainsi que leurs aspirations professionnelles et éducatives. Les résultats de cette étude ont montré que les élèves scolarisés dans des établissements internationaux se distinguent de leurs homologues scolarisés dans des établissements publics ou d'enseignement spécialisé par la perception qu'ils ont d'eux-mÁmes et leurs choix de carrière. Ces résultats font l'objet de discussions quant à leur pertinence pour la recherche future et l'influence éventuelle de l'éducation internationale sur les élèves d'une région. Spanish En este estudio se analiza cómo influyen los colegios internacionales en los alumnos originarios del país donde se encuentran estos colegios en lo que respecta a su identidad individual y colectiva, sus aspiraciones profesionales y el tipo y la ubicación de la universidad en la que desean estudiar. Se seleccionó una muestra aleatoria de 270 adolescentes de colegios internacionales, especializados (magnet schools) y públicos de Qatar, y se les pidió que completaran un cuestionario con el objetivo de determinar cómo percibían su identidad, así como sus aspiraciones profesionales y educativas. Los resultados del estudio muestran que los alumnos que estudiaban en colegios internacionales tenían una percepción de sí mismos y de sus oportunidades profesionales diferente de la de los alumnos de los otros colegios. Se analiza la importancia de los resultados para futuras investigaciones y la influencia que los colegios internacionales pueden tener en dichos alumnos.
International education
Authors: Naidoo Vikash 
Published: December 2006

English Recent developments in the international education industry are notable in three respects. First, international student mobility has more than doubled in the last two decades or so. Second, programme mobility encompassing distance education has also led to new forms of cross-border education. Third, institution mobility through such commercial deals as franchises and twinning arrangements are becoming an increasingly important feature of cross-border education, although on a limited scale. Such developments are leading to the emergence of a new market place for the international education industry. This article documents and analyses trends in painting a picture of these contemporary developments in cross-border education. French Il est possible de distinguer des évolutions récentes dans le domaine de l'éducation internationale et ce, à trois niveaux. Tout d'abord, la’mobilité des étudiants internationaux a plus que doublé au cours des vingt dernières années. Deuxièmement, la mobilité des programmes englobant l'enseignement à distance a également engendré de nouvelles formes d'éducation internationale. En dernier lieu, la souplesse des institutions à travers des relations commerciales telles que les franchises et les accords de jumelage deviennent des caractéristiques d'éducation internationale de plus en plus importantes bien qu'elles n'existent que sur une échelle limitée. De telles évolutions donnent naissance à un nouveau marché consacré au domaine de l'éducation internationale. Cet article illustre et analyse les tendances de ces évolutions contemporaines dans l'éducation internationale. Spanish Los últimos desarrollos en el ámbito de la industria de la educatión internacional se pueden apreciar desde tres ángulos principales. En’primer lugar, la movilidad de estudiantes internacionales se ha más que duplicado en las dos últimas décadas. En segundo lugar, la’movilidad curricular generada por la modalidad de educación transfronteriza. En tercer lugar, las franquicias, los programas académicos interinstitucionales y otras formas de acuerdos han generado una movilidad institucional que se está convirtiendo en una caracteristica importante de la educación transfronteriza, si bien en escala aún reducida. A consecuencia de estos desarrollos ha surgido un nuevo mercado para la industria de la educación internacional. Este trabajo documenta y analiza las tendencias que intentan describir estos desarrollos actuales en la educación transfronteriza.
Interactive intergenerational learning in the context of CAS in the IB Diploma Programme
Authors: Cambridge James , Simandiraki Anna 
Published: December 2006

English Creativity, Action, Service (CAS) forms a core component of the International Baccalaureate Diploma Programme. CAS frequently includes intergenerational practice involving school students and older adults. This article reports the development of a typology to describe and analyse learning that arises from intergenerational practice in three dimensions comprising the type of intergenerational relationship forming the context for learning, what is learned as an outcome of the intergenerational interaction, and how learning is accomplished. It also reports the validation of the typology in a pilot study examining the extent of intergenerational practice in the context of CAS in UK schools offering the IB Diploma, with an aim to internationalize this research in the future. French Les activités CAS (créativité, action, service) constituent une composante au cóur du Programme du diplôme du Baccalauréat International. Le programme CAS inclut fréquemment un apprentissage intergénérationnel auquel participent les élèves de l'établissement et des adultes plus âgés. Cet article présente le développement d'une typologie pour décrire et analyser l'apprentissage qui découle de cette pratique intergénérationnelle dans trois aspects: le type de relation intergénérationnelle qui forme le contexte d'apprentissage, les enseignements apportés par l'interaction intergénérationnelle et la façon dont l'apprentissage est réalisé. Cet article présente également la vérification de cette typologie à travers une étude pilote s'intéressant à l'ampleur de l'apprentissage intergénérationnel dans le contexte du programme CAS dans les établissements qui dispensent le Programme du diplôme du BI au Royaume-Uni, dans le but d'internationaliser cette recherche à l'avenir. Spanish Creatividad, Acción y Servicio (CAS) constituye un componente central del Programa del Diploma del Bachillerato Internacional. Con frecuencia, este componente incluye prácticas intergeneracionales en las que participan alumnos de un colegio y personas de la tercera edad. En este artículo se informa del desarrollo de una tipología para describir y analizar el aprendizaje derivado de la práctica intergeneracional y se establecen tres dimensiones: el tipo de relación intergeneracional que proporciona el contexto para el aprendizaje, lo que se aprende como resultado de la interacción intergeneracional y cómo se produce el aprendizaje. También se informa sobre la validación de esta tipología mediante un estudio piloto en el que se analiza el grado de práctica intergeneracional que existe en el contexto de CAS en los colegios del Reino Unido que ofrecen el Programa del Diploma del BI, con el objetivo de extender esta investigación a otros países en el futuro.
Effect of ageing on the nature and interlayering of mixed hydroxy A1-Fe-montmorillonite complexes
Authors: Colombo C. , Violante A. 
Published: December 2006

AbstractMixed hydroxy Al-Fe-montmorillonite complexes (5 mmol of Al+Fe per g of clay) were prepared at pH 5.0 by mixing different amounts of Al(NO3)3 and Fe(NO3)3 to give initial Fe/Al molar ratios (R) of 0, 0.1, 0.25, 0.5, 1.0, 4.0, 10.0 or ∞. The effect of ageing on the interlayering, mineralogy, chemical composition, CEC and external surface area of the complexes was studied. The degree of interlayering of freshly prepared and aged complexes (up to 120 days at 50°C) was always greater in the samples with R ranging from 0.5 to 4. Gibbsite and hematite (with traces of goethite) formed in the samples with R ⩽ 1 and R∞, respectively. No crystalline Fe oxide was detected by XRD analyses in the complexes with R ranging from 0.1 to 10, whereas no crystalline Al and Fe oxides were formed in the complexes at R = 4–10. However, some evidence suggests the possible formation of a microcrystalline Fe oxide/oxyhydroxide undetectable by XRD analyses in the complexes richer in Fe. The CEC and the surface area of the freshly prepared mixed hydroxy Al-Fe-montmorillonite complexes increased with increasing R. Large quantities of Al+Fe were solubilized by oxalate in the complexes with R ⩾ 0.5, even after ageing for 120 days at 50°C, indicating that interlayering of Al-Fe species at certain Fe/Al molar ratios was particularly stable.
X-ray diffraction, infrared and TGA/DTG analysis of hydrated nacrite
Authors: Ben Haj Amara A. 
Published: December 2006

AbstractAn homogenous 8.4 Å hydrate was obtained after washing intercalated KAc- nacrite. X-ray diffraction analysis based on comparison of the experimental and calculated profiles enabled the amount of water (one molecule per Si2Al2O5(OH)4) and the z coordinate along c* (6.5 Å) to be determined. The hydration state was accompanied by a decrease in the coherent domain along c* in the order nacrite > KAc-nacrite > H2O-nacrite. The IR spectrum of the hydrated nacrite showed an evolution of the structure with a shift of ν(OH) from 3702, 3649 and 3630 cm−1 to 3690, 3641 and 3620 cm−1, respectively for the nacrite hydroxyls. The ν(OH) stretching bands of the interlayer water appeared at 3602 and 3545 cm−1 and their bending band at 1655 cm−1. The TGA/DTG analysis of the air-dry hydrated nacrite showed a loss of water at 245°C the weight loss (1 molecule per Si2Al2O5(OH)4) corresponding to the interlamellar water, in agreement with that determined by XRD.
Kaolinite hydroxyls – a Raman microscopy study
Authors: Frost R. L. , van der Gaast S. J. 
Published: December 2006

AbstractRaman microscopy of the kaolinite polymorphs was used to study single crystals and bundles of aligned crystals of kaolinite. The spectra of the hydroxyl stretching region were both sample and orientation dependent. Kaolinites can be classified into two groups according to the ratio of the intensities of the 3685 and 3695 cm−1 bands. No relationship was found between the d-spacing and the crystal domain size measurement from the 001 reflection and the Raman spectral intensities indicating the Raman spectra are independent of d-spacing and crystallinity. However, a relationship of the crystallinity in the a-b direction and intensities of the 3685 and 3695 cm−1 bands indicate that the relative position of one layer to the other determines the position of the inner surface hydroxyl groups and the hydrogen bonding with the oxygen of the opposite layer. A new hypothesis based on symmetric and non-symmetric hydrogen bonding of the inner surface hydroxyl groups is proposed to explain the two inner surface hydroxyl bands centred at 3685 and 3695 cm−1. The bands at 3670 and 3650 cm−1 are described in terms of the out-of-phase vibrations of the in-phase vibrations at 3695 and 3685 cm−1.
Dehydration and rehydration of vermiculites: III. Phlogopitic Sr- and Ba-vermiculite
Authors: Graf v. Reichenbach H. , Beyer J. 
Published: December 2006

AbstractDehydration and rehydration of a phlogopitic vermiculite saturated with either Sr2+ or Ba2+ were studied by thermoanalysis (TG, DSC, DTA) and by in situ X-ray powder diffractometry. A detailed analysis of the relationship between temperature and state of hydration of the vermiculites close to equilibrium at atmospheric pressure was rendered possible by use of low heating rates in combination with a fast recording position-sensitive detector. For Sr-vermiculite, the results reveal the existence of a number of distinct states of hydration characterized by basal spacings of 1.54, 1.51, 1.49, 1.23, 1.21 and 0.96 nm. The Ba-vermiculite failed to develop a two-layer hydrate even in contact with water. Its one-layer hydrate (1.24 nm) was reversibly transformed into an incompletely dehydrated ordered ‘mica-structure’ (1.00-0.99 urn), before an irreversibly dehydrated structure was attained at temperatures exceeding 700°C The formation of regular 1:1 interstratification was confirmed for all transformations characterized by a change in the number of water layers. The concluding compilation summarizes basal spacings, stacking orders, layer translations and specific water contents for all discrete states of hydration observed in our experiments at saturation of vermiculite with different alkaline earth cations.
The structure of an intercalated ordered kaolinite — a Raman microscopy study
Authors: Frost R. L. , Tran T. H. , Kristof J. 
Published: December 2006

AbstractChanges in the molecular structure of a highly ordered kaolinite, intercalated with urea and potassium acetate, have been studied using Raman microscopy. A new Raman band, attributed to the inner surface hydroxyl groups strongly hydrogen bound to the acetate, is observed at 3605 cm-1 for the potassium acetate intercalate with the consequential loss of intensity in the bands at 3652, 3670, 3684 and 3693 cm-1. Remarkable changes in intensity of the Raman spectral bands of the low-frequency region of the kaolinite occurred upon intercalation. In particular, the 144 and 935 cm-1 bands increased by an order of magnitude and were found to be polarized. These spectroscopic changes provide evidence for the inner surface hydroxyl group-acetate bond being at an angle approaching 90° to the 001 face. Decreases in intensity of the bands at 243, 271 and 336 cm-1 were observed. The urea intercalate shows additional Raman bands at 3387, 3408 and 3500 cm-1 which are attributed to N-H vibrations after formation of the urea-kaolinite complex. Changes in the spectra of the inserting molecules were also observed.
Characterization and catalytic properties of a saponite clay modified by acid activation
Authors: Kooli F. , Jones W. 
Published: December 2006

AbstractA natural saponite was acid activated at room temperature or 90°C with different acid/clay ratios and the products were characterized by powder X-ray diffraction, infrared spectroscopy and thermogravimetry. The leaching of Mg from the octahedral sheets is enhanced by an increase in the acid/clay ratio and by an increase in temperature of activation. Textural properties are reported, and it appears that they are strongly correlated to the presence of a noncrystalline silica phase which is formed during the acid activation process. The desorption of cyclohexylamine indicates that for samples activated at 90°C the number of acid sites in the acidactivated saponites decreases following severe acid treatment. Infrared spectroscopy of adsorbed pyridine on samples after calcination at 500°C suggests that acid activation at 90°C produces a single type of Bronsted site but two types of Lewis sites whereas activation at room temperature results in only one type of Lewis site in addition to a Brønsted site. The two Lewis sites are suggested to originate from residual Al in the clay structure and to AI exsolved from the layers during activation. The dehydration of pentan-1-ol has been used as a further probe to measure acidity by monitoring the degree of conversion and selectivity for the different samples.
Bmi-1 is induced by the Epstein-Barr virus oncogene LMP1 and regulates the expression of viral target genes in Hodgkin lymphoma cells
Authors: Dutton Amanda , Woodman Ciaran B. , Chukwuma Marilyn B. , Last James I. K. , Wei Wenbin , Vockerodt Martina , Baumforth Karl R. N. , Flavell Joanne R. , Rowe Martin , Taylor A. Malcolm R. , Young Lawrence S. , Murray Paul G. 
Published: December 2006

Abstract
Polycomb group (PcG) proteins are chromatin modifiers that are necessary for the maintenance and renewal of embryonic and adult stem cells. However, overexpression of the PcG protein, Bmi-1, causes lymphoma in transgenic mice. We show that Bmi-1 is up-regulated in Hodgkin lymphoma (HL) cells by the Epstein-Barr virus (EBV) oncogene latent membrane protein-1 (LMP1) and that this up-regulation is mediated by NF-κB signaling. We also show that Bmi-1 is up-regulated by NF-κB in EBV-negative HL cells. Down-regulation of LMP1 and Bmi-1 decreased the survival of HL cells, suggesting that Bmi-1 may mediate the prosurvival effects of LMP1-induced NF-κB signaling in HL cells. Transcriptional targets of Bmi-1 were identified after its knockdown in an HL cell line. We show here that Bmi-1 and LMP1 down-regulate the ataxia telangiectasia–mutated (ATM) tumor suppressor and conclude that Bmi-1 contributes to LMP1-induced oncogenesis in HL.
CpG oligodeoxynucleotides allow for effective adoptive T-cell therapy in chronic retroviral infection
Authors: Kraft Anke R. M. , Krux Frank , Schimmer Simone , Ohlen Claes , Greenberg Philip D. , Dittmer Ulf 
Published: December 2006

AbstractAdoptive T-cell therapy in cancer or chronic viral infections is often impeded by the development of functional impairment of the transferred cells. To overcome this therapeutic limitation we combined adoptive transfer of naive, virus-specific CD8+ T cells with immunostimulative CpG oligodeoxynucleotides (ODNs) in mice chronically infected with the Friend retrovirus. The CpG-ODN co-injection prevented the T cells from developing functional defects in IFNγ and granzyme production and degranulation of cytotoxic molecules. Thus, the transferred T cells were able to reduce chronic viral loads when combined with CpG-ODNs. This strategy provides a new approach for developing successful adoptive T-cell therapy against chronic infections.
Cartography of gene expression in CD8 single cells: novel CCR7− subsets suggest differentiation independent of CD45RA expression
Authors: Monteiro Marta , Evaristo César , Legrand Agnès , Nicoletti Antonino , Rocha Benedita 
Published: December 2006

AbstractUnderstanding the distribution, function, and lineage relationship of CD8+ T-cell subpopulations is of fundamental value for the monitoring of the immune system in several experimental and clinical situations. However, the available data concerning the description of effector and memory CD8+ subsets in humans remain rather fragmentary because different studies favored the usage of distinct and restricted sets of cell surface markers and functional parameters. We associated multiple markers to subdivide CD8+ T cells into 14 different cell types, several of which were not described previously, and evaluated the coexpression of 18 genes simultaneously in individual cells from each subset. Our results show that each subset has a defined pattern of gene expression. Moreover, effector gene expression of CCR7− cells correlated only with CD27 expression levels and CD27/CD28 coexpression but not with CD45RA/R0 phenotypes. Our findings thus describe new CD8+ cell subsets, allow the identification of relatively homogeneous CD8+ subpopulations, provide a predictable and precise correlation between particular cell surface markers and CD8+ T-cell functional properties, and identify effector cells present in both CCR7−CD45RA+ and CCR7−CD45R0+ compartments. The results also indicate that activated cells might modulate the expression of CD45RA/R0 asynchronously rather than CCR7−CD45RA+ cells always issuing from CD45RA− precursors.
Interleukin 2 gene transcription is regulated by Ikaros-induced changes in histone acetylation in anergic T cells
Authors: Bandyopadhyay Sanmay , Duré Myrianne , Paroder Monika , Soto-Nieves Noemí , Puga Irene , Macián Fernando 
Published: December 2006

AbstractIn T cells anergy may be evoked by an unbalanced stimulation of the T-cell receptor in the absence of costimulation. Anergic T cells are unresponsive to new antigen receptor engagement and do not produce interleukin 2. We present evidence that anergizing stimuli induce changes in histone acetylation, which mediates transcriptional repression of interleukin 2 expression. In response to calcium signaling, anergic T cells up-regulate the expression of Ikaros, a zinc finger transcription factor essential for lymphoid lineage determination. Ikaros binds to the interleukin 2 promoter where it induces histone deacetylation. Confirming the role of Ikaros in the induction of T-cell anergy, cells with reduced Ikaros activity show defective inactivation in response to an anergizing stimulus. We propose a model in which tolerizing stimuli induce epigenetic changes on the interleukin 2 locus that are responsible for the stable inhibition of the expression of this cytokine in anergic T cells.
Bortezomib, melphalan, prednisone, and thalidomide for relapsed multiple myeloma
Authors: Palumbo Antonio , Ambrosini Maria Teresa , Benevolo Giulia , Pregno Patrizia , Pescosta Norbert , Callea Vincenzo , Cangialosi Clotilde , Caravita Tommaso , Morabito Fortunato , Musto Pellegrino , Bringhen Sara , Falco Patrizia , Avonto Ilaria , Cavallo Federica , Boccadoro Mario ,   for the Italian Multiple Myeloma Network, Gruppo Italiano Malattie Ematologiche dell'Adulto (GIMEMA)
Published: December 2006

AbstractIn multiple myeloma (MM), the addition of thalidomide or bortezomib to the standard oral melphalan/prednisone combination significantly increased response rate and event-free survival. In this multicenter phase 1/2 trial, dosing, safety, and efficacy of the 4-drug combination, bortezomib, melphalan, prednisone, and thalidomide (VMPT) was determined. Bortezomib was administered at 3 dose levels (1.0 mg/m2, 1.3 mg/m2, or 1.6 mg/m2) on days 1, 4, 15, and 22; melphalan was given at a dose of 6 mg/m2 on days 1 through 5 and prednisone at 60 mg/m2 on days 1 through 5. Thalidomide was delivered at 50 mg on days 1 through 35. Each course was repeated every 35 days. The maximum tolerated dose of bortezomib was 1.3 mg/m2. Thirty patients with relapsed or refractory MM were enrolled; 20 patients (67%) achieved a partial response (PR) including 13 patients (43%) who achieved at least a very good PR. Among 14 patients who received VMPT as second-line treatment, the PR rate was 79% and the immunofixation-negative complete response rate 36%. The 1-year progression-free survival was 61%, and the 1-year survival from study entry was 84%. Grade 3 nonhematologic adverse events included infections (5 patients), fatigue (1), vasculitis (1), and peripheral neuropathy (2); no grade 4 toxicities were recorded. Initial results showed that VMPT is an effective salvage therapy with a very high proportion of responses. The incidence of neurotoxicities was unexpectedly low.