bluuebunny/crossref_metadata_2025 huggingface dataset:
Short-Chain Fatty Acids Stimulate Glucagon-Like Peptide-1 Secretion via the G-Protein–Coupled Receptor FFAR2
Authors: Tolhurst Gwen , Heffron Helen , Lam Yu Shan , Parker Helen E. , Habib Abdella M. , Diakogiannaki Eleftheria , Cameron Jennifer , Grosse Johannes , Reimann Frank , Gribble Fiona M.
Published: December 2011

Interest in how the gut microbiome can influence the metabolic state of the host has recently heightened. One postulated link is bacterial fermentation of “indigestible” prebiotics to short-chain fatty acids (SCFAs), which in turn modulate the release of gut hormones controlling insulin release and appetite. We show here that SCFAs trigger secretion of the incretin hormone glucagon-like peptide (GLP)-1 from mixed colonic cultures in vitro. Quantitative PCR revealed enriched expression of the SCFA receptors ffar2 (grp43) and ffar3 (gpr41) in GLP-1–secreting L cells, and consistent with the reported coupling of GPR43 to Gq signaling pathways, SCFAs raised cytosolic Ca2+ in L cells in primary culture. Mice lacking ffar2 or ffar3 exhibited reduced SCFA-triggered GLP-1 secretion in vitro and in vivo and a parallel impairment of glucose tolerance. These results highlight SCFAs and their receptors as potential targets for the treatment of diabetes.
Growth, optical and EPR properties of Li1.72Na0.28Ge4O9 single crystals pure and slightly doped with Cr
Authors: Jasik Anna , Berkowski Marek , Kaczmarek Slawomir , Suchocki Andrzej , Kaminska Agata , Leniec Grzegorz , Nowakowski Piotr , Domukhovski Viktor
Published: December 2011

Single crystals of lithium-sodium-tetragermanate, a member of the solid solution series Li2−xNaxGe4O9 with x=0.28, pure and slightly doped with Cr3+ ions (0.03 mol.% and 0.1 mol.%), were grown in ambient atmosphere by the Czochralski technique from stoichiometric melt. The crystals with dimensions up to 20 mm in diameter and 50 mm in length were obtained. The crystal structure has been determined by means of X-ray diffraction. Phase analysis and structural refinement of the Li1.72Na0.28Ge4O9 crystals were performed by X-ray powder diffraction using Ni-filtered Cu Kα radiation with a Siemens D5000 diffractometer. The absorption, excitation and photoluminescence spectra of the crystals were measured in the UV-VIS and IR range at low temperatures. EPR investigations were performed using a conventional X-band Bruker ELEXSYS E 500 CW-spectrometer operating at 9.5 GHz with 100 kHz magnetic field modulation. Temperature and angular dependences of the EPR spectra of the crystal samples were recorded in the 3–300 K temperature range.
Peer Review: Fetishes, Fallacies, and Perceptions
Authors: Derricourt Robin
Published: December 2011

The key to a successful program of scholarly book publishing lies with the knowledge, creativity, and drive of the commissioning (acquisitions) editor. Peer review is a useful tool for testing and confirming the editor's judgment and arguing the case for publication, but the role of peer review alone can often be overrated. Too many funding and appointment systems are based on a fetishised image of this concept. Despite the debates and changing perceptions about scholarly books, it is editorial excellence that underlies the quality and importance of a list. While journals rely more on the formal process of peer review, the role of the entrepreneurial journal editor also remains important to scholarly communication.
Animal model of intramedullary spinal cord glioma using human glioblastoma multiforme neurospheres
Authors: Hsu Wesley , Siu I-Mei , Pradilla Gustavo , Gokaslan Ziya L. , Jallo George I. , Gallia Gary L.
Published: December 2011

Object

Advances in the diagnosis and management of patients with spinal cord tumors have been limited because of the rarity of the disease and the limitations of current animal models for spinal cord glioma. The ideal spinal cord tumor model would possess a number of characteristics, including the use of human glioma cells that capture the growth pattern and local invasive nature of their human counterpart. In this study, the authors' goal was to develop a novel spinal cord tumor model using a human neurosphere cell line.

Methods

Eighteen female athymic rats were randomized into 3 experimental groups. Animals in the first group (6 rats) received a 3-ml intramedullary injection containing DMEM and were used as controls. Animals in the second group (6 rats) received a 3-ml intramedullary injection containing 100,000 glioblastoma multiforme (GBM) neurosphere cells in 3 ml DMEM. Animals in the third group (6 rats) received a 3-ml intramedullary injection containing 9L gliosarcoma cells in 3 ml DMEM. Functional testing of hindlimb strength was assessed using the Basso-Beattie-Bresnahan (BBB) scale. Once the functional BBB score of an animal was less than or equal to 5 (slight movement of 2 joints and extensive movement of the third), euthanasia was performed.

Results

Animals in the GBM neurosphere group had a mean survival of 33.3 ± 2.0 days, which was approximately twice as long as animals in the 9L gliosarcoma group (16.3 ± 2.3 days). There was a significant difference between survival of the GBM neurosphere and 9L gliosarcoma groups (p < 0.001). None of the control animals died (p < 0.001 for GBM neurosphere group vs controls and 9L vs controls). Histopathological examination of the rats injected with 9L gliosarcoma revealed that all animals developed highly cellular, well-circumscribed lesions causing compression of the surrounding tissue, with minimal invasion of the surrounding gray and white matter. Histopathological examination of animals injected with GBM neurospheres revealed that all animals developed infiltrative lesions with a high degree of white and gray matter invasion along with areas of necrosis.

Conclusions

The authors have established a novel animal model of spinal cord glioma using neurospheres derived from human GBM. When injected into the spinal cords of athymic nude rats, neurospheres gave rise to infiltrative, actively proliferating tumors that were histologically identical to spinal cord glioma in humans. On the basis of their results, the authors conclude that this is a reproducible animal model of high-grade spinal cord glioma based on a human GBM neurosphere line. This model represents an improvement over other models using nonhuman glioma cell lines. Novel therapeutic strategies can be readily evaluated using this model.
Protein Kinases and Transcription Factors Activation in Response to UV-Radiation of Skin: Implications for Carcinogenesis
Authors: López-Camarillo César , Aréchaga Ocampo Elena , López Casamichana Mavil , Pérez-Plasencia Carlos , Álvarez-Sánchez Elizbeth , Marchat Laurence A.
Published: December 2011

Solar ultraviolet (UV) radiation is an important environmental factor that leads to immune suppression, inflammation, photoaging, and skin carcinogenesis. Here, we reviewed the specific signal transduction pathways and transcription factors involved in the cellular response to UV-irradiation. Increasing experimental data supporting a role for p38, MAPK, JNK, ERK1/2, and ATM kinases in the response network to UV exposure is discussed. We also reviewed the participation of NF-κB, AP-1, and NRF2 transcription factors in the control of gene expression after UV-irradiation. In addition, we discussed the promising chemotherapeutic intervention of transcription factors signaling by natural compounds. Finally, we focused on the review of data emerging from the use of DNA microarray technology to determine changes in global gene expression in keratinocytes and melanocytes in response to UV treatment. Efforts to obtain a comprehensive portrait of the transcriptional events regulating photodamage of intact human epidermis after UV exposure reveals the existence of novel factors participating in UV-induced cell death. Progress in understanding the multitude of mechanisms induced by UV-irradiation could lead to the potential use of protein kinases and novel proteins as specific targets for the prevention and control of skin cancer.
Theory of the Origin, Evolution, and Nature of Life
Authors: Andrulis Erik D.
Published: December 2011

Life is an inordinately complex unsolved puzzle. Despite significant theoretical progress, experimental anomalies, paradoxes, and enigmas have revealed paradigmatic limitations. Thus, the advancement of scientific understanding requires new models that resolve fundamental problems. Here, I present a theoretical framework that economically fits evidence accumulated from examinations of life. This theory is based upon a straightforward and non-mathematical core model and proposes unique yet empirically consistent explanations for major phenomena including, but not limited to, quantum gravity, phase transitions of water, why living systems are predominantly CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur), homochirality of sugars and amino acids, homeoviscous adaptation, triplet code, and DNA mutations. The theoretical framework unifies the macrocosmic and microcosmic realms, validates predicted laws of nature, and solves the puzzle of the origin and evolution of cellular life in the universe.
Method of Preventing Shrinkage of Aluminum Foam Using Carbonates
Authors: Koizumi Takuya , Kido Kota , Kita Kazuhiko , Mikado Koichi , Gnyloskurenko Svyatoslav , Nakamura Takashi
Published: December 2011

Metallic foams are commonly produced using titanium hydride as a foaming agent. Carbonates produce aluminum foam with a fine and homogenous cell structure. However, foams produced using carbonates show marked shrinkage, which is clearly different from those produced using titanium hydride. It is essential for practical applications to clarify foam shrinkage and establish a method of preventing it. In this research, cell structures were observed to study the shrinkage of aluminum foam produced using carbonates. The cells of foam produced using dolomite as a foaming agent connected to each other with maximum expansion. It was estimated that foaming gas was released through connected cells to the outside. It was assumed that cell formation at different sites is effective in preventing shrinkage induced by cell connection. The multiple additions of dolomite and magnesium carbonate, which have different decomposition temperatures, were applied. The foam in the case with multiple additions maintained a density of 0.66 up to 973 K, at which the foam produced using dolomite shrank. It was verified that the multiple additions of carbonates are effective in preventing shrinkage.
The Biological Response of Spermidine Induced by Ionization Radiation
Authors: Roh Changhyun , Yu Dong-Kyung , Kim Insub , Jo Sung Kee
Published: December 2011

Globally, there are concerns over the risks associated with radiation exposure, so it is important to understand the biological effects of radiation exposure. Driven by the need to detect the presence of radiation exposure, biomarkers to monitor potential exposure after radiological accidents can be developed and would be extremely valuable for biological response. In this study, the behavior of spermidine as a biomarker was investigated in a C57BL/6 mouse model exposed to an acute whole-body sublethal dose of 6 Gy. The spermidine content values in serum increased for up to two days after 6 Gy irradiation. However, the enhanced spermidine content observed on day +3 in irradiated mice returned to normal levels on the subsequent five days. The result indicates that spermidine can be used as a biomarker of biological response to radiation exposure.
Understanding and Ameliorating Non-Linear Phase and Amplitude Responses in AMCW Lidar
Authors: Godbaz John P. , Cree Michael J. , Dorrington Adrian A.
Published: December 2011

Amplitude modulated continuous wave (AMCW) lidar systems commonly suffer from non-linear phase and amplitude responses due to a number of known factors such as aliasing and multipath inteference. In order to produce useful range and intensity information it is necessary to remove these perturbations from the measurements. We review the known causes of non-linearity, namely aliasing, temporal variation in correlation waveform shape and mixed pixels/multipath inteference. We also introduce other sources of non-linearity, including crosstalk, modulation waveform envelope decay and non-circularly symmetric noise statistics, that have been ignored in the literature. An experimental study is conducted to evaluate techniques for mitigation of non-linearity, and it is found that harmonic cancellation provides a significant improvement in phase and amplitude linearity.
Direct monitoring of opto-mechanical switching of self-assembled monolayer films containing the azobenzene group
Authors: Tirosh Einat , Benassi Enrico , Pipolo Silvio , Mayor Marcel , Valášek Michal , Frydman Veronica , Corni Stefano , Cohen Sidney R
Published: December 2011

The potential for manipulation and control inherent in molecule-based motors holds great scientific and technological promise. Molecules containing the azobenzene group have been heavily studied in this context. While the effects of the cis–trans isomerization of the azo group in such molecules have been examined macroscopically by a number of techniques, modulations of the elastic modulus upon isomerization in self-assembled films were not yet measured directly. Here, we examine the mechanical response upon optical switching of bis[(1,1'-biphenyl)-4-yl]diazene organized in a self-assembled film on Au islands, using atomic force microscopy. Analysis of higher harmonics by means of a torsional harmonic cantilever allowed real-time extraction of mechanical data. Quantitative analysis of elastic modulus maps obtained simultaneously with topographic images show that the modulus of the cis-form is approximately twice that of the trans-isomer. Quantum mechanical and molecular dynamics studies show good agreement with this experimental result, and indicate that the stiffer response in the cis-form comprises contributions both from the individual molecular bonds and from intermolecular interactions in the film. These results demonstrate the power and insights gained from cutting-edge AFM technologies, and advanced computational methods.
Continuous proline catalysis via leaching of solid proline
Authors: Opalka Suzanne M , Longstreet Ashley R , McQuade D Tyler
Published: December 2011

Herein, we demonstrate that a homogeneous catalyst can be prepared continuously via reaction with a packed-bed of a catalyst precursor. Specifically, we perform continuous proline catalyzed α-aminoxylations using a packed-bed of L-proline. The system relies on a multistep sequence in which an aldehyde and thiourea additive are passed through a column of solid proline, presumably forming a soluble oxazolidinone intermediate. This transports a catalytic amount of proline from the packed-bed into the reactor coil for subsequent combination with a solution of nitrosobenzene, affording the desired optically active α-aminooxy alcohol after reduction. To our knowledge, this is the first example in which a homogeneous catalyst is produced continuously using a packed-bed. We predict that the method will not only be useful for other L-proline catalyzed reactions, but we also foresee that it could be used to produce other catalytic species in flow.
La guerre coloniale du Bani-Volta, 1915-1916 (Burkina-Faso, Mali)
Authors: Royer Patrick
Published: December 2011

Résumé En 1915, les habitants d’une vaste région, qui s’étend du fleuve Bani (Mali) à la boucle de la Volta (Burkina-Faso), déclarèrent la guerre au pouvoir colonial et s’engagèrent à ne déposer les armes qu’après le départ définitif des Européens. Malgré une disparité militaire apparemment insurmontable, les chefs de guerre promettaient la victoire en recourant à des arguments de différents ordres, parmi lesquels la protection de puissances tutélaires et l’allègement de la présence coloniale dès le début de la première guerre mondiale. Depuis la conquête de la région, presque vingt ans auparavant, la population avait adopté une attitude de consentement apparent qui n’était qu’une réponse temporaire à une nouvelle donne politique. Bien qu’inévitablement influencés par la vision coloniale, les chefs de guerre s’appuyaient sur une stratégie de réactivation d’alliances précoloniales. La tradition orale relate une guerre entre deux adversaires indépendants et non une rébellion contre une autorité suprême, une vue d’ailleurs partagée par quelques administrateurs coloniaux de l’époque. Les interprétations divergentes des belligérants sur la nature du conflit posent le problème de la guerre coloniale qui a pour postulat un rapport d’inégalité nié par les combattants anticoloniaux.
Soudan et Somalie : de la fabrication ethnique par la guerre
Authors: Pérouse de Montclos Marc-Antoine
Published: December 2011

Résumé La guerre tend à précipiter les différenciations ethniques dans le sang. Elle conjugue deux phénomènes le regroupement dans des enclaves militaires ou des camps de déplacés, d’une part, et la dispersion à l’étranger ou, à tout le moins, hors du terroir natal, d’autre part. Du Soudan à la Somalie, les deux cas d’étude retenus le montrent bien. Au Soudan, un pouvoir autoritaire a tenté de diviser pour mieux régner et mater la rébellion du Sud, attisant les dissensions internes aux guérillas. En Somalie, l’effondrement de l’État a vu l’aide humanitaire prendre le relais. Tandis que les identités claniques se forgeaient au scalpel, les procédures d’attribution du statut de réfugié ont contribué à préciser les sentiments d’appartenance à des « minorités vulnérables ».
Rivalités, territoire et santé : enjeux et constats pour une vraie démocratie sanitaire
Authors: Cépré Ludovic
Published: December 2011

La santé est un champ sur lequel les rivalités, y compris territoriales, entre acteurs sont en expansion. Un recul du niveau de santé aurait de lourdes conséquences politiques. Les dirigeants politiques ont réagi à ce danger en instituant un système de gestion recentré sur les décisions de l’État, mais en le régionalisant. Or le lien entre espace et santé est en train de se densifier : on voit croître la ségrégation sociale, que ce soit pour l’habitat, l’offre de soins, ou les plus grandes densités de pathologies. L‘avancée majeure de la loi HPST est peut-être d’avoir ouvert la voie à une régionalisation réelle du système de santé. Elle passerait par une prise en charge sciemment différenciée d’une région à l’autre. Mais la culture de santé publique de la classe politique s’appuie souvent sur des représentations vieillies, naïves ou même erronées, trop centrées sur l’offre de soins, et la gestion différenciée de la santé selon le territoire nécessiterait une très solide construction sociale et démocratique de son mode de gestion. Les déterminants de santé ne sont plus que de façon minoritaire liés à l’offre de soins, comme le montre par exemple le niveau de couverture vaccinale, alors que le défi sanitaire majeur qui se présente à nous dans les prochaines années oblige à repenser la santé publique : les baby-boomers arrivent à l’âge de l’enclenchement des premières maladies chroniques.
L'épidémie de choléra en Haïti : lecture géopolitique d'un enjeu de santé publique
Authors: Guimier Lucie
Published: December 2011

Les indicateurs sanitaires et sociaux reflètent l’instabilité politique et les carences économiques dont souffre Haïti. Pour exemple, un indicateur de développement important souligne les déficiences sanitaires du pays : le quotient de mortalité infanto-juvénile atteint 86 pour 1000 naissances ; en d’autres termes, environ un enfant sur douze meurt avant d’atteindre l’âge de cinq ans. Dans de telles conditions, la survenue de l’épidémie de choléra en octobre 2010, de surcroît dans une période post-séisme chaotique, ne peut que plonger le pays dans une situation sanitaire totalement désordonnée. L’approche géographique qui suit s’applique à apprécier l’impact de l’infection dans l’espace, à plusieurs échelles d’observation, et à reconnaître les discontinuités spatiales de prévalence et d’incidence. L’objectif est ensuite de comprendre les lois qui régissent les différences d’impact et d’évolution observées, en identifiant la territorialisation de l’accès aux soins dans l’espace haïtien. In fine , la progressive prise de pouvoir des acteurs de l’aide internationale dans le domaine de la santé pose le problème de l’essoufflement des services de santé haïtiens en faveur du secteur privé, une rupture que la crise sanitaire actuelle n’a fait qu’exacerber.
Incidence du développement de la « conscience parentale de l'Autre-bébé » durant la grossesse sur la qualité des interactions précoces (0-3 mois)
Authors: Bertrand Samuel
Published: December 2011

Résumé Les recherches sur les interactions précoces et le bébé interrogent de plus en plus l’intersubjectivité et le sujet dont les définitions sont devenues insuffisantes en psychologie. Après avoir trouvé un fondement de celles-ci dans la phénoménologie husserlienne, l’hypothèse est faite que la qualité des interactions précoces (0-3 mois) est corrélée au développement de la « conscience parentale de l’Autre-bébé », s’annonçant dans les représentations parentales prénatales et sous-tendue par la relation fœto-parentale, la narrativité et la fonction réflexive parentales, durant la grossesse. Cette hypothèse a été testée sur 13 couples, primipares, suivis du troisième mois de grossesse au troisième mois du bébé. À partir d’une approche qualitative et d’une méthodologie descriptive , les résultats montrent que les interactions précoces (dyadiques et triadiques) sont d’autant plus adéquates que la conscience parentale du bébé est développée. Celle-ci se constitue d’autant plus précocement durant la grossesse que les parents ont des représentations « intégrées/équilibrées ». La qualité de ces représentations est liée au développement harmonieux d’une part de la relation fœto-parentale, d’autre part de la narrativité et de la fonction réflexive parentales, qui permettent, ou non, une incarnation croissante du sujet dans une position de narrateur distancié de son récit, dans laquelle l’autre et soi ont chacun leur place, ensemble. Enfin, cette recherche montre la nécessité de considérer la relation parents/enfant et son évolution au carrefour de l’intrapsychique et du dyadique dans le triangle primaire (père/mère/bébé).
Intervenir dans la réalité lors de cures avec des enfants placés
Authors: Mounier Bruno
Published: December 2011

Résumé Recevoir en psychothérapie des enfants placés en famille d’accueil est difficile. D’une part ces enfants se protègent beaucoup de leur réalité psychique et d’autre part les problèmes de réalité extérieure sont envahissants et interfèrent dans la cure. Plutôt que d’ignorer ces incursions de la réalité extérieure, il est préférable de les prendre en compte, voire d’intervenir dans cette réalité concrète. Cette intervention du psychanalyste dans la réalité, pour peu orthodoxe qu’elle soit, s’est révélée être un moyen privilégié pour avoir accès à la réalité psychique de ces enfants et permettre à ces thérapies de déboucher sur de véritables changements.
L'enfant avec un autisme et l'animal dans un lien signifiant : des possibilités d'interventions thérapeutiques
Authors: Maurer Marie , Delfour Fabienne , Trudel Marcel , Adrien Jean-Louis
Published: December 2011

Résumé Le lien avec l’animal se construit précocement au cours du développement de l’enfant. Il présente certaines caractéristiques qui le différencient d’une relation avec un être humain. Ainsi si l’animal fait, également, preuve de contingence, son comportement est plus prévisible et moins complexe que celui d’un humain. L’enfant peut mettre en signification l’animal : lui donner du sens. D’autre part, la communication avec l’animal s’effectue, davantage, sur un mode non verbal et implique, de façon privilégiée, la modalité tactile. Ces spécificités en font un partenaire plus accessible pour l’enfant sans trouble de développement et constituent de réels atouts dans un travail de type thérapeutique auprès d’enfants atteints d’autisme. En effet, l’autisme se caractérise par des difficultés interactionnelles et communicatives qui pourraient être améliorées suite à un contact structuré avec l’animal. Cet article a donc pour objectif de faire le point sur les principaux arguments théoriques qui font de l’animal un partenaire singulier pour l’enfant en général et pour l’enfant avec un autisme en particulier.
« Un retour aux anciennes maisons de fous » ? Réformer les institutions psychiatriques en Russie soviétique (1918-1928)
Authors: Dufaud Grégory
Published: December 2011

Résumé Avec la révolution d’Octobre, une partie des psychiatres se rallia aux bolcheviks qui leur donnèrent « carte blanche » pour réaliser les réformes qu’ils réclamaient de longue date. La Commission de neurologie et de psychiatrie, créée en 1918, s’employa alors à améliorer le fonctionnement des institutions psychiatriques, les hôpitaux en premier lieu dans le but d’en faire de véritables structures de soin. Pourtant, en 1928, un projet de décret constatait, pour le dénoncer, que la production médicale y était des plus médiocres. C’est l’objet de cet article que d’étudier les retombées de la politique conduite en faveur des établissements psychiatriques et, par là, de faire ressortir les facteurs qui ont pu peser sur sa réussite. Pour cela, un parcours kaléidoscopique est proposé qui entend confronter les conditions héritées du tsarisme, les objectifs institutionnels, le rôle du personnel et la place des reclus.
Se baigner ensemble
Authors: Lombardo Davide
Published: December 2011

En 1839, Honoré Daumier commence à publier des lithographies dédiées aux baigneurs, qui, l’été, se délassent dans les établissements ouverts en bord de Seine. La pratique des bains était alors l’objet d’une réglementation de plus en plus stricte, dans une ville qui dans les années trente et quarante, allait subir de profondes transformations (même si celles-ci furent moins spectaculaires que celles des années cinquante) : pavage des rues, système d’égouts. Daumier fait un usage très original de ses baigneurs, usage qui se situe bien au delà des productions dominantes de l’époque visant à représenter le corps du baigneur - hygiénique, sociale, érotique ou esthétique. Daumier se moque de la culture hygiéniste (et des tensions entre classes) qui touche au thème des bains. Il subvertit le corps idéal bourgeois en le dévoilant dans toute son animalité, mais en même temps, il se refuse à adopter un regard érotique quand il figure des scènes de sociabilité. La stratégie de Daumier n’est pas celle d’une résistance ou subversion des idées et valeurs reçues à propos du corps, il s’agit plutôt d’une affirmation de l’expressivité du corps lui-même et d’une recherche sur son quotidien.
Rire, une forme de réception de l'urbanisme moderne
Authors: Ratouis Olivier
Published: December 2011

En France et plus généralement en Europe, la modernité urbaine connaît un moment charnière dans les années 1950, marqué par la reconstruction d’aprèsguerre et la rupture des modes de vie souvent qualifiée « d’américanisation ». Ces changements suscitent différentes émotions parmi lesquelles le rire constitue à titre individuel et collectif une forme de prise de distance et d’appropriation d’une réalité mouvante, que l’on se propose ici d’étudier à partir des vecteurs de la nouvelle culture de masse. Considérant les œuvres comiques comme des formes de réception de l’urbanisme moderne, l’article s’appuie sur un corpus d’œuvres françaises et belges comiques et burlesques dont le pivot est l’année 1958, relevant, par leur succès et leur aura, de la « culture populaire ». Elles sont contextualisées dans l’actualité que souvent elles commentent, en particulier Mon Oncle de Jacques Tati et le Salon des arts ménagers, les œuvres du dessinateur André Franquin et l’Exposition internationale de Bruxelles (dite «Expo ’58»).
La disparition du temps en relativité
Authors: Lachièze-Rey Marc
Published: December 2011

Résumé La révolution einsteinienne – construction des théories de la relativité – repose sur la disparition du temps, au profit de l’espace-temps isotrope. Je la compare à la révolution newtonienne, vue comme une disparition de la verticale au profit de l’espace isotrope. J’analyse l’existence et la pertinence de notions à caractère temporel dans les théories relativistes ; en particulier temps et durées propres, et causalité.
Occuper le temps
Authors: During Élie
Published: December 2011

Résumé Dans les débats métaphysiques contemporains, « endurer » et « perdurer » désignent deux manières irréductibles de persister dans le temps et de subir le changement. Parce qu’ils mobilisent différemment la forme de représentation « espace-temps », ces schèmes conceptuels révèlent peut-être deux figures ou deux aspects du temps lui-même.
Amplificación cruzada de microsatélites en el género Centaurea (Compositae)
Authors: López-Vinyallonga S.
Published: December 2011

Amplificación cruzada de microsatélites en el género Centaurea (Compositae).- Los microsatélites se usan habitualmente en estudios de genética de poblaciones aunque su desarrollo es un proceso caro y largo dada su elevada especificidad. Una estrategia que permite ahorrar tiempo y dinero es la llamada amplificación cruzada que consiste en amplificar el DNA de una especie determinada (especie objetivo) usando marcadores que han sido diseñados para una especie diferente (especie fuente). En este trabajo se ha realizado un ensayo sobre amplificación cruzada usando seis endemismos del género Centaurea y dos conjuntos de microsatélites: i) 16 marcadores nucleares desarrollados para tres especies congenéricas y ii) 10 marcadores cloroplásticos universales diseñados para Nicotiana tabacum. Diecisiete de los 26 marcadores evaluados resultaron transferibles, de los cuales 14 fueron polimórficos siendo así útiles para futuros trabajos. Las regiones nucleares se mostraron más variables y por lo tanto más informativas que las cloroplásticas. La amplificación cruzada funcionó mejor para los marcadores nucleares específicos de Centaurea que para los cloroplásticos universales específicos de Nicotiana tabacum. A su vez, se obtuvo mejor resultado para las especies de la sección Phalolepis que para las de la sección Lepteranthus. En consecuencia, nuestros resultados apoyan la idea de que el éxito de la amplificación cruzada está estrechamente ligado a la distancia evolutiva entre especie fuente y especie objetivo
Adiciones para la flora de Tenerife (Islas Canarias, España)
Authors: Verloove F. , Reyes-Betancort J. A.
Published: December 2011

Adiciones para la flora de Tenerife (Islas Canarias, España).- Algunos recientes trabajos de campo en Tenerife, especialmente en Septiembre de 2010, trajeron consigo varias nuevas e interesantes adiciones de plantas vasculares no autóctonas. Bothriochloa ischaemum var. songarica, Cardamine flexuosa “Asiática”, Cestrum parqui, Digitaria violascens, Ficus lyrata, Ficus rubiginosa, Hoffmannseggia glauca, Hyparrhenia rufa subsp. altissima, Jacaranda mimosifolia, Merremia tuberosa, Passiflora morifolia, Phytolacca dioica, Schefflera actinophylla y Solanum abutiloides son citadas por primera vez para las islas Canarias mientras que Eragrostis barrelieri var. pygmaea, Ficus microcarpa, Ipomoea purpurea, Leucaena leucocephala subsp. glabrata, Sechium edule, Tradescantia zebrina y Turnera ulmifolia son nuevas para la flora de la isla de Tenerife. Nuevas localidades para Acacia cyclops, Atriplex suberecta, Heliotropium curassavicum, Paspalum dilatatum, P. notatum, Pluchea ovalis, Pulicaria paludosa, Sclerophylax spinescens y Solanum villosum subsp. miniatum confirman su reciente expansión en la isla de Tenerife. También se recogen nuevas localidades para el recientemente descrito Sporobolus copei. Finalmente, se confirma para la isla de Tenerife Paspalum vaginatum (hasta ahora posiblemente confundido con P. distichum) y Potentilla indica.
Notas sobre el tamaño del genoma en el híbrido Ranunculus x luizetii (Ranunculaceae) y sus progenitores mediante citometría de flujo
Authors: Cires E. , Cuesta C. , Fernández Prieto J. A.
Published: December 2011

Notas sobre el tamaño del genoma en el híbrido Ranunculus x luizetii (Ranunculaceae) y sus progenitores mediante citometría de flujo.- Se ha empleado la citometría de flujo para estimar el contenido de ADN nuclear en el híbrido Ranunculus x luizetii y sus progenitores. Nuestros resultados indican que el tamaño del genoma del híbrido R. x luizetii se acerca más a R. pyrenaeus que a R. parnassiifolius, con una evidencia de reducción del genoma.
Towards Work-Based Mobile Learning
Authors: Pimmer Christoph , Pachler Norbert , Attwell Graham
Published: December 2011

Mobile devices are increasingly being used to support learning in work contexts. In exploring the emerging field of work-based mobile learning (WBML), researchers need to give consideration to the theoretical and empirical findings from mobile and work-based learning. In this paper, the authors provide an overview of key issues and dominant debates in these fields with the aim of providing a systematic introduction for mobile learning researchers interested in exploring the use of mobile devices for learning in work-based contexts. This paper’s focus is aimed at scoping possible commonalities across mobile and work-based learning in order to establish a baseline for future conceptual work in empirical research towards WBML.
Analysis of Success Factors in Social Networking Website Development
Authors: Zahari Zanita , Pardede Eric
Published: December 2011

The popularity and rapid growth of social networking sites is undeniable. However, it is hard to guarantee the success and sustainability of these sites. This study will focus on identifying the key success factors for each phase in agile iteration development for social networks. A qualitative and quantitative analysis was adopted using web analytical tools to gather and measure these success factors. A comparative study between popular and unpopular social networking was undertaken to gather realistic data. Results reveal that determinants of success for agile development phases include: goal setting, developing brand image, quality content, trust building, user-centered design, technology and client server platform, service quality, user satisfaction and stability. The successful implementation of these factors will benefit developers and users in order to achieve the success and survival of the social networking website development.
Community Structure Extraction for Social Networks
Authors: Hadush Helen , Zheng Gaolin , Chen Chung-Hao , Huang E-Wen
Published: December 2011

In this work, community structure extraction essentially resorts to its solution to graph partition problem. The authors explore two different approaches. The spectral approach is based on the minimization of balanced cut and its resulting solution comes from the spectral decomposition of the graph Laplacian. The modularity based approach is based on the maximization of modularity and implemented in a hierarchical fashion. In practice, the approach can extract useful information from the community structure, such as what is the most influential component in a given community. Being able to identify and group friends on social networks, the technique can provide a customized advertisement based on their interests. This can have a big return in terms of marketing efficiency. Community structure can also be used for network visualization and navigation. As a result, it can be seen which groups or which pages have more interaction, thus giving a clear image for navigation purposes.
The Impact of National Culture on Information Systems Planning Autonomy
Authors: Mirchandani Dinesh A. , Lederer Albert L.
Published: December 2011

Hofstede’s national culture model has been applied in prior research to better understand the management of multinational firms. That research suggests that national culture may influence the information systems planning autonomy of the subsidiaries of multinational firms, but such an impact has not yet been tested empirically. A postal survey of 131 chief information officers and 103 senior non-IS managers of U.S. subsidiaries of such firms collected data to test hypotheses based on the model. Structural equation modeling using PLS-Graph 3.0 revealed that Individualism-Collectivism, Masculinity-Femininity, and Uncertainty Avoidance predicted autonomy for particular IS planning phases (as rated by the CIOs). On the basis of the supported hypotheses, the study provides evidence of the relevance of the national culture model to IS planning effectiveness and IS contribution. The study also suggests to subsidiary managers that an understanding of the national culture of their parent firm can help them gain an insight into the parent’s management perspective.
An International Comparative Study of the Roles, Rules, Norms, and Values That Predict Email use
Authors: Peterson Mark F. , Thomason Stephanie J. , Althouse Norm , Athanassiou Nicholas , Curri Gudrun , Konopaske Robert , Lenartowicz Tomasz , Meckler Mark , Mendenhall Mark E. , Mogaji Andrew A. , Rowney Julie I.A.
Published: December 2011

This chapter extends communication and technology use theories about factors that predict e-mail use by explaining the reasons for cultural contingencies in the effects of managers’ personal values and the social structures (roles, rules and norms) that are most used in their work context. Results from a survey of 576 managers from Canada, the English-speaking Caribbean, Nigeria, and the United States indicate that e-mail use may support participative and lateral decision making, as it is positively associated with work contexts that show high reliance on staff specialists especially in the U.S., subordinates, and unwritten rules especially in Nigeria and Canada. The personal value of self-direction is positively related to e-mail use in Canada, while security is negatively related to e-mail use in the United States. The results have implications for further development of TAM and media characteristic theories as well as for training about media use in different cultural contexts.
IS-Supported Managerial Control for China’s Research Community
Authors: Tian Wen , Vogel Douglas R. , Ma Jian , Gu Jibao
Published: December 2011

In the first decade of the 21st century, China’s Research Community (CRC) is struggling to achieve better performance by increasing growth in knowledge quantity (e.g., publications), but has failed to generate sound growth in knowledge quality (e.g., citations). An innovative E-government project, Internet-based Science Information System (ISIS), was applied nationwide in 2003 with a variety of embedded incentives. The system has been well received and supports the National Natural Science Foundation of China (NSFC) to implement managerial control to cope with pressing demands relating to China’s research productivity. This paper explores the impact of Information Systems (IS) from the perspective of agency theory based on CRC empirical results. Since the nationwide application of ISIS in 2003, CRC outcomes have markedly improved. The discussion and directions for future research examine implications of IS for E-government implementation and business environment building in developing countries.
Coping with Accessibility and Usability Challenges of Online Technologies by Blind Students in Higher Education
Authors: Muwanguzi Samuel , Lin Lin
Published: December 2011

This study examined the usability challenges and emotional reactions blind college students experienced in accessing educational materials and communicating with professors and colleagues through online technologies. A case study approach was adopted. Five students were interviewed regarding their online learning experiences using Blackboard, a popular Course Management System. Analysis of the interviews revealed that the blind students found Blackboard poorly accessible, which affected their academic achievements. However, despite their frustrations and feelings of marginalization, the study also showed that the blind students were motivated and optimistic of their successes. The research suggests that academic administrators and CMS designers work jointly with adaptive software developers to create enhanced user interfaces, ensure universal access and usability of online technologies, and reduce educational inequities and frustrations encountered by blind students.
The Emotional Labor of Imagining Otherwise
Authors: de Freitas Elizabeth
Published: December 2011

The concept of emotional resistance is often used to describe student reluctance to grapple with difficult facts regarding inequity and injustice, especially if the students themselves are implicated in these facts by way of their privilege or advantage. Many successful students are reluctant to acknowledge how they are tacitly invested in a governing hegemonic system that has afforded them particular socio-cultural and economic status. Dorsey (2002), for instance, follows her largely white students’ resistance to anti-racist pedagogy through a series of stages - discovery, dismay, denial, and dismissal - all of which indicate their reluctance to realize how their own positioning is enabled through hegemonic systems of oppression. Similarly, Boler and Zembylas (2003) note that students often refuse to recognize “race/ethnicity” differences as significant contributing factors of social capital, arguing for a benign tolerance of difference or denying difference as a significant factor.
Innovative Methods of Teaching Integrity and Ethics in Management Education
Authors: Odrakiewicz Peter
Published: December 2011

The key role of values and norms in organizational culture are closely related to integrity, moral and ethical concerns and should be taught using innovative case studies, video-conferences, role-playing dilemmas, video-interviews, collaborative blog-based methodology, integrity project participation and intensive social media use in management education.
Antibacterial properties of an Indian traditional medicinal plant, Rhynchosia scarabaeoides (L.) DC. (Fabaceae)
Authors: Challa Surekha , Rajam Kiran K. , Satyanarayana Kasapu Vishnu V. V. , Kumar Tanneeru Suresh , Kantamreddi Venkata Siva Satyanarayana
Published: December 2011

Rhynchosia scarabaeoides (L.) DC plant parts are extensively used by traditional healers in India to treat a variety of bacterial diseases, such as dysentery, diarrohea and skin disorders. This article reports the antibacterial activities of n-hexane, ethyl acetate and ethanol extracts belonging to the leaf, stem and root parts of R. scarabaeoides against five bacterial strains, Bacillus subtilis, Escherichia coli, Klebseilla pneumonia, Proteus vulgaris and Staphylococcus aureus, using an agar gel diffusion method. The range of inhibition zone (IZ) was found to be 15-24 mm and the minimum inhibitory activity (MIC) was found to be 1 mL/well. The IZ was found to be higher in ethyl acetate extracts while this was moderate in ethanol extracts, and no activity was seen with n-hexane extracts or root extracts. The MIC value of leaf ethyl acetate extract was found to be 1 mg against bacterial strains P. vulgaris and S. aureus, whereas 2 mg was found against B. subtilis, K. pneumoniae and E. coli. These results support the traditional usage of R. scarabaeoides plant parts in the treatment of bacterial infections. Interestingly, this plant was screened for antibacterial activity for the first time and was found to be active. Detailed chemical investigations are, therefore, warranted.
Lushness, Numerical Index 1 and the Daugavet Property in Rearrangement Invariant Spaces
Authors: Kadets Vladimir , Martín Miguel , Merí Javier , Werner Dirk
Published: December 2011

We show that for spaces with 1–unconditional bases lushness, the alternative Daugavet property and numerical index 1 are equivalent. In the class of rearrangement invariant (r.i.) sequence spaces the only examples of spaces with these properties are c0, ℓ1andℓ∞. The only lush r.i. separable function space on [0, 1] is L1[0, 1]; the same space is the only r.i. separable function space on [0, 1] with the Daugavet property over the reals.
Lagrange's Theorem for Hopf Monoids in Species
Authors: Aguiar Marcelo , Lauve Aaron
Published: December 2011

Following Radford's proof of Lagrange's theorem for pointed Hopf algebras, we prove Lagrange‘s theorem for Hopf monoids in the category of connected species. As a corollary, we obtain necessary conditions for a given subspecieskof a Hopf monoidhto be a Hopf submonoid: the quotient of any one of the generating series ofhby the corresponding generating series ofkmust have nonnegative coefficients. Other corollaries include a necessary condition for a sequence of nonnegative integers to be the dimension sequence of a Hopfmonoid in the formof certain polynomial inequalities and of a set-theoretic Hopf monoid in the form of certain linear inequalities. The latter express that the binomial transform of the sequence must be nonnegative.
AICAR, a Small Chemical Molecule, Primes Osteogenic Differentiation of Adult Mesenchymal Stem Cells
Authors: Wu Wei , Ye Zhaoyang , Zhou Yan , Tan Wen-Song
Published: December 2011

The chemical approach to controlling stem cell fates is emerging as a powerful tool, holding great promise in tissue engineering and regenerative medicine. Various small molecules have been demonstrated capable of modulating stem cell differentiation. In this paper, we studied the effects of 5-aminoimidazole-4-carboxamide-1-β-riboside (AICAR), an activator of AMP-activated protein kinase (AMPK), on mesenchymal stem cells (MSCs). AICAR at high concentrations (1.0–2.0 mM) significantly inhibited proliferation of both human amnion-derived MSCs (hAMSCs) and rabbit bone marrow-derived MSCs (BM-MSCs). Most importantly, AICAR efficiently promoted the osteogenic differentiation of hAMSCs and BM-MSCs in both growth medium and osteogenic medium. However, Metformin, another AMPK activator, showed no such effects. Meanwhile, AICAR significantly inhibited adipogenic differentiation of hAMSCs and BM-MSCs. Our data suggests that AICAR represents a potent molecule, which can be applied in bone tissue regeneration.
Boarding Duration in the Emergency Department and Inpatient Delirium and Severe Agitation
Authors: Joseph Joshua W. , Elhadad Noémie , Mattison Melissa L.P. , Nentwich Lauren M. , Levine Sharon A. , Marcantonio Edward R. , Kennedy Maura
Published: June 2024

This cohort study examines the risk factors for developing delirium and/or agitation in patients in the emergency department waiting for an inpatient bed.
Comprehensive Defect Suppression in Te‐Doped Cs2ZrCl6 Perovskite Nanoparticles for Highly Efficient and Thermally Stable White Light‐Emitting Diodes
Authors: Yang Chaojun , Tian Xiangdan , Huang Guangguang , Xiong Xinyang , Sun Kaiwei , Zhang Bo , Wang Shujie , Du Zuliang
Published: June 2024

Cesium zirconium halide (e.g., Cs2ZrCl6:Te or CZCT) perovskites have garnered significant interest due to their unique optical properties. However, there have been no reports of CZCT perovskite nanoparticles (PNPs) that simultaneously offer high efficiency and thermal stability. Here, a comprehensive defect suppression strategy is reported to achieve CZCT PNPs with these attributes. First, the inner defects of CZCT perovskite microcrystals (PMCs) are minimized by controlling crystallization kinetics precisely. Second, the PNPs are obtained from PMCs via top‐down fabrication, and the surface defects of PNPs are passivated via the hydroxyl groups of alkyl‐terminated silica‐oligomer shell (ASO). The resulting CZCT@ASO PNPs show the highest photoluminescence quantum yield (PLQY) of 96% and high thermal stability among the reported conventional CZCT emitters. Finally, white light‐emitting diodes (WLEDs) are integrated by using CZCT@ASO PNPs as the down‐color converters, achieving a color coordinate of (0.31, 0.33) and a color rendering index of 86. These results demonstrate that core/shell CZCT@ASO PNPs have great potential as phosphors for lighting applications.