bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantum Dots-Based Immunofluorescent Imaging of Stromal Fibroblasts Caveolin-1 and Light Chain 3B Expression and Identification of Their Clinical Significance in Human Gastric Cancer
Authors: He Yuyu , Zhao Xianda , Gao Jun , Fan Lifang , Yang Guifang , Cho William , Chen Honglei
Published: October 2012

Caveolin-1 (Cav-1) expression deficiency and autophagy in tumor stromal fibroblasts (hereafter fibroblasts) are involved in tumor proliferation and progression, particularly in breast and prostate cancer. The aim of this study was to detect the expression of fibroblastic Cav-1 and LC3B, markers of autophagy, in gastric cancer (GC) and to analyze their clinical significances. Furthermore, because Epstein-Barr virus (EBV)-associated GC (EBVaGC) is a unique subtype of GC; we compared the differential expression of fibroblastic Cav-1 and LC3B in EBVaGC and non-EBVaGC. Quantum dots (QDs)-based immunofluorescence histochemistry was used to examine the expression of fibroblastic Cav-1 and LC3B in 118 cases of GC with adequate stroma. QDs-based double immunofluorescence labeling was performed to detect the coexpression of Cav-1 and LC3B proteins. EBV-encoded small RNA was detected by QDs-based fluorescence in situ hybridization to identify EBVaGC. Multivariate analysis indicated that low fibroblastic Cav-1 level was an independent prognosticator (p = 0.029) that predicted poorer survival of GC patients. Positive fibroblastic LC3B was correlated with lower invasion (p = 0.032) and was positively associated with Cav-1 expression (r = 0.432, p < 0.001). EBV infection did not affect fibroblastic Cav-1 and LC3B expression. In conclusion, positive fibroblastic LC3B correlates with lower invasion, and low expression of fibroblastic Cav-1 is a novel predictor of poor GC prognosis.
Insulin Modifies Honeybee Worker Behavior
Authors: Mott Christine , Breed Michael
Published: October 2012

The insulin signaling pathway has been hypothesized to play a key role in regulation of worker social insect behavior. We tested whether insulin treatment has direct effects on worker honeybee behavior in two contexts, sucrose response thresholds in winter bees and the progression to foraging by summer nurse bees. Treatment of winter worker bees with bovine insulin, used as a proxy for honeybee insulin, increased the bees’ sucrose response threshold. Treatment of summer nurse bees with bovine insulin significantly decreased the age at which foraging was initiated. This work provides further insight into the role of endocrine controls in behavior of in honeybees and insects in general.
Materials-Related Aspects of Thermochemical Water and Carbon Dioxide Splitting: A Review
Authors: Roeb Martin , Neises Martina , Monnerie Nathalie , Call Friedemann , Simon Heike , Sattler Christian , Schmücker Martin , Pitz-Paal Robert
Published: October 2012

Thermochemical multistep water- and CO2-splitting processes are promising options to face future energy problems. Particularly, the possible incorporation of solar power makes these processes sustainable and environmentally attractive since only water, CO2 and solar power are used; the concentrated solar energy is converted into storable and transportable fuels. One of the major barriers to technological success is the identification of suitable active materials like catalysts and redox materials exhibiting satisfactory durability, reactivity and efficiencies. Moreover, materials play an important role in the construction of key components and for the implementation in commercial solar plants. The most promising thermochemical water- and CO2-splitting processes are being described and discussed with respect to further development and future potential. The main materials-related challenges of those processes are being analyzed. Technical approaches and development progress in terms of solving them are addressed and assessed in this review.
Development of New Drugs for an Old Target — The Penicillin Binding Proteins
Authors: Zervosen Astrid , Sauvage Eric , Frère Jean-Marie , Charlier Paulette , Luxen André
Published: October 2012

The widespread use of β-lactam antibiotics has led to the worldwide appearance of drug-resistant strains. Bacteria have developed resistance to β-lactams by two main mechanisms: the production of β-lactamases, sometimes accompanied by a decrease of outer membrane permeability, and the production of low-affinity, drug resistant Penicillin Binding Proteins (PBPs). PBPs remain attractive targets for developing new antibiotic agents because they catalyse the last steps of the biosynthesis of peptidoglycan, which is unique to bacteria, and lies outside the cytoplasmic membrane. Here we summarize the “current state of the art” of non-β-lactam inhibitors of PBPs, which have being developed in an attempt to counter the emergence of β-lactam resistance. These molecules are not susceptible to hydrolysis by β-lactamases and thus present a real alternative to β-lactams. We present transition state analogs such as boronic acids, which can covalently bind to the active serine residue in the catalytic site. Molecules containing ring structures different from the β-lactam-ring like lactivicin are able to acylate the active serine residue. High throughput screening methods, in combination with virtual screening methods and structure based design, have allowed the development of new molecules. Some of these novel inhibitors are active against major pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and thus open avenues new for the discovery of novel antibiotics.
Aqueous Synthesis of 1-H-2-Substituted Benzimidazoles via Transition-Metal-Free Intramolecular Amination of Aryl Iodides
Authors: Chen Chunxia , Chen Chen , Li Bin , Tao Jingwei , Peng Jinsong
Published: October 2012

A straightforward method has been developed for the synthesis of the benzimidazole ring system through a carbon-nitrogen cross-coupling reaction. In the presence of 2.0 equiv. of K2CO3 in water at 100 °C for 30 h, the intramolecular cyclization of N-(2-iodoaryl)benzamidine provides benzimidazole derivatives in moderate to high yields. Remarkably, the procedure occurs exclusively in water and doesn’t require the use of any additional reagent/catalyst, rendering the methodology highly valuable from both environmental and economical points of view.
Improving the Fermentation Production of the Individual Key Triterpene Ganoderic Acid Me by the Medicinal Fungus Ganoderma lucidum in Submerged Culture
Authors: Liu Gao-Qiang , Wang Xiao-Ling , Han Wen-Jun , Lin Qin-Lu
Published: October 2012

Enhanced ganoderic acid Me (GA-Me, an important anti-tumor triterpene) yield was attained with the medicinal fungus Ganoderma lucidum using response surface methodology (RSM). Interactions were studied with three variables, viz. glucose, peptone and culture time using a Central Composite Design (CCD). The CCD contains a total of 20 experiments with the first 14 experiments organized in a fractional factorial design, with the experimental trails from 15 to 20 involving the replications of the central points. A polynomial model, describing the relationships between the yield of GA-Me and the three factors in a second-order equation, was developed. The model predicted the maximum GA-Me yield of 11.9 mg·L−1 for glucose, peptone, culture time values of 44.4 g·L−1, 5.0 g·L−1, 437.1 h, respectively, and a maximum GA-Me yield of 12.4 mg·L−1 was obtained in the validation experiment, which represented a 129.6% increase in titre compared to that of the non-optimized conditions. In addition, 11.4 mg·L−1 of GA-Me was obtained in a 30-L agitated fermenter under the optimized conditions, suggesting the submerged culture conditions optimized in the present study were also suitable for GA-Me production on a large scale.
From Exit to Entry: Long-term Survival and Transmission of Salmonella
Authors: Waldner Landon L. , MacKenzie Keith D. , Köster Wolfgang , White Aaron P.
Published: October 2012

Salmonella spp. are a leading cause of human infectious disease worldwide and pose a serious health concern. While we have an improving understanding of pathogenesis and the host-pathogen interactions underlying the infection process, comparatively little is known about the survival of pathogenic Salmonella outside their hosts. This review focuses on three areas: (1) in vitro evidence that Salmonella spp. can survive for long periods of time under harsh conditions; (2) observations and conclusions about Salmonella persistence obtained from human outbreaks; and (3) new information revealed by genomic- and population-based studies of Salmonella and related enteric pathogens. We highlight the mechanisms of Salmonella persistence and transmission as an essential part of their lifecycle and a prerequisite for their evolutionary success as human pathogens.
Phylogeny of Cirsium spp. in North America: Host Specificity Does Not Follow Phylogeny
Authors: Slotta Tracey , Horvath David , Foley Michael
Published: October 2012

Weedy invasive Cirsium spp. are widespread in temperate regions of North America and some of their biological control agents have attacked native Cirsium spp. A phylogenetic tree was developed from DNA sequences for the internal transcribed spacer and external transcribed spacer regions from native and non-native Great Plains Cirsium spp. and other thistles to determine if host specificity follows phylogeny. The monophyly of Cirsium spp. and Carduus within the tribe Cardinae was confirmed with native North American and European lineages of the Cirsium spp. examined. We did not detect interspecific hybridization between the introduced invasive and the native North American Cirsium spp. Selected host-biological control agent interactions were mapped onto the phylogenic tree derived by maximum likelihood analysis to examine the co-occurrence of known hosts with biological control agents. Within Cirsium-Cardueae, the insect biological control agents do not associate with host phylogenetic lines. Thus, more comprehensive testing of species in host-specificity trials, rather than relying on a single representative of a given clade may be necessary; because the assumption that host-specificity follows phylogeny does not necessarily hold. Since the assumption does not always hold, it will also be important to evaluate ecological factors to provide better cues for host specificity.
Applicability of the Thermal Infrared Spectral Region for the Prediction of Soil Properties Across Semi-Arid Agricultural Landscapes
Authors: Eisele Andreas , Lau Ian , Hewson Robert , Carter Dan , Wheaton Buddy , Ong Cindy , Cudahy Thomas John , Chabrillat Sabine , Kaufmann Hermann
Published: October 2012

In this study we tested the feasibility of the thermal infrared (TIR) wavelength region (within the atmospheric window between 8 and 11.5 μm) together with the traditional solar reflective wavelengths for quantifying soil properties for coarse-textured soils from the Australian wheat belt region. These soils have very narrow ranges of texture and organic carbon contents. Soil surface spectral signatures were acquired in the laboratory, using a directional emissivity spectrometer (μFTIR) in the TIR, as well as a bidirectional reflectance spectrometer (ASD FieldSpec) for the solar reflective wavelengths (0.4–2.5 μm). Soil properties were predicted using multivariate analysis techniques (partial least square regression). The spectra were resampled to operational imaging spectroscopy sensor characteristics (HyMAP and TASI-600). To assess the relevance of specific wavelength regions in the prediction, the drivers of the PLS models were interpreted with respect to the spectral characteristics of the soils’ chemical and physical composition. The study revealed the potential of the TIR (for clay: R2 = 0.93, RMSEP = 0.66% and for sand: R2 = 0.93, RMSEP = 0.82%) and its combination with the solar reflective region (for organic carbon: R2 = 0.95, RMSEP = 0.04%) for retrieving soil properties in typical soils of semi-arid regions. The models’ drivers confirmed the opto-physical base of most of the soils’ constituents (clay minerals, silicates, iron oxides), and emphasizes the TIR’s advantage for soils with compositions dominated by quartz and kaolinite.
Boundary Layer Separation and Reattachment Detection on Airfoils by Thermal Flow Sensors
Authors: Sturm Hannes , Dumstorff Gerrit , Busche Peter , Westermann Dieter , Lang Walter
Published: October 2012

A sensor concept for detection of boundary layer separation (flow separation, stall) and reattachment on airfoils is introduced in this paper. Boundary layer separation and reattachment are phenomena of fluid mechanics showing characteristics of extinction and even inversion of the flow velocity on an overflowed surface. The flow sensor used in this work is able to measure the flow velocity in terms of direction and quantity at the sensor’s position and expected to determine those specific flow conditions. Therefore, an array of thermal flow sensors has been integrated (flush-mounted) on an airfoil and placed in a wind tunnel for measurement. Sensor signals have been recorded at different wind speeds and angles of attack for different positions on the airfoil. The sensors used here are based on the change of temperature distribution on a membrane (calorimetric principle). Thermopiles are used as temperature sensors in this approach offering a baseline free sensor signal, which is favorable for measurements at zero flow. Measurement results show clear separation points (zero flow) and even negative flow values (back flow) for all sensor positions. In addition to standard silicon-based flow sensors, a polymer-based flexible approach has been tested showing similar results.
Profitability of Small-Scale Fisheries in Elmina, Ghana
Authors: Aheto Denis W. , Asare Noble K. , Quaynor Belinda , Tenkorang Emmanuel Y. , Asare Cephas , Okyere Isaac
Published: October 2012

In order to achieve sustainable fishing livelihoods in coastal communities, data on profitability of small-scale fisheries relative to fish species caught and gear types used by fishermen is required as part of a broader fisheries management strategy. This study was undertaken with this in mind. Interviews were conducted among 60 fishermen between February and March 2010. Economic assessment of small-scale fishing activities were done using questionnaires based on direct market pricing and contingent valuation methods. The results indicate that highly profitable fish species include Epinephelus aeneus, Sparus caeruleostictus, Dentex angolensis and Lutjanus goreensis valued at US$2.97, US$2.87, US$2.85 and US$2.63 per kilogram respectively. The less profitable species include Dasyatis margarita, Caranx crysos and Sardinella aurita valued at US$0.34, US$0.66 and US$ 0.85 per kilogram respectively. Although Sardinella aurita was among the less valuable fish species, it was the main species driving profits for the fishermen due to its high share volume among the fish catches. Findings from this study suggest high rates of exploitation, in that stocks generally cannot provide for increased economic return in the face of increased investment. This is a clear indicator that the open-access nature of Ghanaian fisheries is not sustainable, and management reform is well overdue.
Insights into the Functions of a Prophage Recombination Directionality Factor
Authors: Panis Gaël , Franche Nathalie , Méjean Vincent , Ansaldi Mireille
Published: October 2012

Recombination directionality factors (RDFs), or excisionases, are essential players of prophage excisive recombination. Despite the essentially catalytic role of the integrase in both integrative and excisive recombination, RDFs are required to direct the reaction towards excision and to prevent re-integration of the prophage genome when entering a lytic cycle. KplE1, HK620 and numerous (pro)phages that integrate at the same site in enterobacteria genomes (such as the argW tRNA gene) all share a highly conserved recombination module. This module comprises the attL and attR recombination sites and the RDF and integrase genes. The KplE1 RDF was named TorI after its initial identification as a negative regulator of the tor operon. However, it was characterized as an essential factor of excisive recombination. In this study, we designed an extensive random mutagenesis protocol of the torI gene and identified key residues involved in both functions of the TorI protein. We show that, in addition to TorI-TorR protein-protein interaction, TorI interacts in solution with the IntS integrase. Moreover, in vitro, TorR and IntS appear to compete for TorI binding. Finally, our mutagenesis results suggest that the C-terminal part of the TorI protein is dedicated to protein-protein interactions with both proteins TorR and IntS.
Diversity and Adaptation of Human Respiratory Syncytial Virus Genotypes Circulating in Two Distinct Communities: Public Hospital and Day Care Center
Authors: Gardinassi Luiz , Simas Paulo , Gomes Deriane , Bonfim Caroline , Nogueira Felipe , Garcia Gustavo , Carareto Claudia , Rahal Paula , Souza Fátima
Published: October 2012

HRSV is one of the most important pathogens causing acute respiratory tract diseases as bronchiolitis and pneumonia among infants. HRSV was isolated from two distinct communities, a public day care center and a public hospital in São José do Rio Preto – SP, Brazil. We obtained partial sequences from G gene that were used on phylogenetic and selection pressure analysis. HRSV accounted for 29% of respiratory infections in hospitalized children and 7.7% in day care center children. On phylogenetic analysis of 60 HRSV strains, 48 (80%) clustered within or adjacent to the GA1 genotype; GA5, NA1, NA2, BA-IV and SAB1 were also observed. SJRP GA1 strains presented variations among deduced amino acids composition and lost the potential O-glycosilation site at amino acid position 295, nevertheless this resulted in an insertion of two potential O-glycosilation sites at positions 296 and 297. Furthermore, a potential O-glycosilation site insertion, at position 293, was only observed for hospital strains. Using SLAC and MEME methods, only amino acid 274 was identified to be under positive selection. This is the first report on HRSV circulation and genotypes classification derived from a day care center community in Brazil.
Intramyocardial Injections of Human Mesenchymal Stem Cells following Acute Myocardial Infarction Modulate Scar Formation and Improve Left Ventricular Function
Authors: Beitnes Jan Otto , Øie Erik , Shahdadfar Aboulghassem , Karlsen Tommy , Müller Regine M. B. , Aakhus Svend , Reinholt Finn P. , Brinchmann Jan E.
Published: October 2012

Cell therapy is a promising treatment modality to improve heart function in acute myocardial infarction. However, the mechanisms of action and the most suitable cell type have not been finally determined. We performed a study to compare the effects of mesenchymal stem cells (MSCs) harvested from different tissues on LV function and explore their effects on tissue structure by morphometry and histological staining for species and lineage relationship. MSCs from skeletal muscle (SM-MSCs) and adipose tissue (ADSCs) were injected in the myocardium of nude rats 1 week after myocardial infarction. After 4 weeks of observation, LVEF was significantly improved in the SM-MSCs group (39.1%) and in the ADSC group (39.6%), compared to the placebo group (31.0%, p < 0.001 for difference in change between groups). Infarct size was smaller after cell therapy (16.3% for SM-MSCs, 15.8% for ADSCs vs. 26.0% for placebo, p < 0.001), and the amount of highly vascularized granulation tissue in the border zone was significantly increased in both groups receiving MSCs (18.3% for SM-MSCs, 22.6% for ADSCs vs. 13.1% for placebo, p = 0.001). By in situ hybridization, moderate engraftment of transplanted cells was found, but no transdifferentiation to cardiomyocytes, endothelial cells, or smooth muscle cells was observed. We conclude that MSC injections lead to improved LVEF after AMI in rats predominantly by reduction of infarct size. After 4 weeks, we observed modulation of scar formation with significant increase in granulation tissue. Transdifferentiation of MSCs to cardiomyocytes or vascular cells did not contribute significantly in this process. MSCs from skeletal muscle and adipose tissue had similar effects.
Teratocarcinoma Formation in Embryonic Stem Cell-Derived Neural Progenitor Hippocampal Transplants
Authors: Germain Noélle D. , Hartman Nathaniel W. , Cai Chunyu , Becker Sandy , Naegele Janice R. , Grabel Laura B.
Published: October 2012

Embryonic stem cells (ESCs) hold great therapeutic potential due to their ability to differentiate into cells of the three primary germ layers, which can be used to repopulate disease-damaged tissues. In fact, two cell therapies using ESC derivatives are currently in phase I clinical trials. A main concern in using ESCs and their derivatives for cell transplantation is the ability of undifferentiated ESCs to generate tumors in the host. Positive selection steps are often included in protocols designed to generate particular cell types from ESCs; however, the transition from ESC to progenitor cell or terminally differentiated cell is not synchronous, and residual undifferentiated cells often remain. In our transplants of ESC-derived neural progenitors (ESNPs) into the adult mouse hippocampus, we have observed the formation of teratocarcinomas. We set out to reduce teratocarcinoma formation by enrichment of ESNPs using fluorescence-activated cell sorting (FACS) and have found that, although enrichment prior to transplant reduces the overall rate of teratocarcinoma formation, the tumorigenicity of cell batches can vary widely, even after FACS enrichment to as much as 95% ESNPs. Our data suggest that this variability may be due to the percentage of residual ESCs remaining in the transplant cell population and to the presence of pluripotent epiblast-like cells, not previously identified in transplant batches. Our data emphasize the need for stringent characterization of transplant cell populations that will be used for cell replacement therapies in order to reduce the risk of tumor formation.
Early Islet Damage after Direct Exposure of Pig Islets to Blood: Has Humoral Immunity Been Underestimated?
Authors: Van Der Windt Dirk J. , Marigliano Marco , He Jing , Votyakova Tatyana V. , Echeverri Gabriel J. , Ekser Burcin , Ayares David , Lakkis Fadi G. , Cooper David K. C. , Trucco Massimo , Bottino Rita
Published: October 2012

Currently, islet transplantation as a cell therapeutic option for type 1 diabetes occurs via islet injection into the portal vein. Direct contact between islets and blood is a pathophysiological “provocation” that results in the instant blood-mediated inflammatory reaction (IBMIR) and is associated with early islet loss. However, the nature of the various insults on the islets in the blood stream remains mostly unknown. To gain insight into the mechanisms, we utilized a simplified in vitro model in which islets were exposed to blood in different clinically relevant but increasingly challenging, autologous, allogeneic, and xenogeneic combinations. Irrespective of the blood type and species compatibility, islets triggered blood clotting. Islet damage was worse as islet, and blood compatibility diminished, with substantial islet injury after exposure of porcine islets to human blood. Islet damage involved membrane leakage, antibody deposition, complement activation, positive staining for the membrane attack complex, and mitochondrial dysfunction. Islet damage occurred even after exposure to plasma only, and specific complement inactivation and neutralization of IgM substantially prevented islet damage, indicating the importance of humoral immunity. Efficacious measures are needed to reduce this injury, especially in view of a potential clinical use of porcine islets to treat diabetes.
In Vivo Differentiation of Human Amniotic Epithelial Cells into Cardiomyocyte-Like Cells and Cell Transplantation Effect on Myocardial Infarction in Rats: Comparison with Cord Blood and Adipose Tissue-Derived Mesenchymal Stem Cells
Authors: Fang Cheng-Hu , Jin Jiyong , Joe Jun-Ho , Song Yi-Sun , So Byung-Im , Lim Sang Moo , Cheon Gi Jeong , Woo Sang-Keun , Ra Jeong-Chan , Lee Young-Yiul , Kim Kyung-Soo
Published: October 2012

Human amniotic epithelial cells (h-AECs), which have various merits as a cell source for cell therapy, are known to differentiate into cardiomyocytes in vitro. However, the ability of h-AECs to differentiate into cardiomyocytes in vivo and their cell transplantation effects on myocardial infarction are still unknown. In this study, we assessed whether h-AECs could differentiate into cardiomyocytes in vivo and whether h-AECs transplantation can decrease infarct size and improve cardiac function, in comparison to transplantation of cord blood-derived mesenchymal stem cells (MSCs) or adipose tissue-derived MSCs. For our study, we injected h-AECs, cord blood-derived MSCs, adipose tissue-derived MSCs, and saline into areas of myocardial infarction in athymic nude rats. After 4 weeks, 3% of the surviving h-AECs expressed myosin heavy chain, a marker specific to the myocardium. Compared with the saline group, all cell-implanted groups showed a higher ejection fraction, lower infarct area by positron emission tomography and histology, and more abundant myocardial gene and protein expression in the infarct area. We showed that h-AECs can differentiate into cardiomyocyte-like cells, decrease infarct size, and improve cardiac function in vivo. The beneficial effects of h-AECs were comparable to those of cord blood and adipose tissue-derived MSCs. These results support the need for further studies of h-AECs as a cell source for myocardial regeneration due to their plentiful availability, low immunity, and lack of ethical issues related to their use.
Design and synthesis of a photoswitchable guanidine catalyst
Authors: Viehmann Philipp , Hecht Stefan
Published: October 2012

A novel design as well as a straight-forward synthesis for a photoswitchable guanidine catalyst is reported. Intense studies of the photochromic properties demonstrated the reversible switchability of its photosensitive azobenzene moiety. Its activity in the ring-opening polymerization (ROP) of rac-lactide was investigated as well. The obtained results are discussed, and an additional guanidine was synthesized and utilized in the ROP of rac-lactide in order to explain the findings.
La différenciation sociale des enfants
Authors: Lignier Wilfried , Lomba Cédric , Renahy Nicolas
Published: October 2012

Résumé Les sciences sociales ne constituent pas des sciences « habituelles » de l’enfance, par comparaison avec les sciences cliniques et médicales en particulier. Pourtant, elles peuvent apporter beaucoup à la compréhension du jeune âge, autour des notions d’historicisation de l’enfance, de socialisation primaire ou encore de différenciation sociale des enfants. Cette dernière entrée est ici privilégiée, sachant qu’elle a l’avantage de ne pas exclure les deux autres – on parlera ainsi d’historicisation et de socialisation différenciées. Nous insistons sur trois manières distinctes d’aborder la différenciation des enfants : par la différenciation « concrète » des enfances, par l’identification différentielle des enfants, par les perceptions enfantines des différences sociales. Nous évoquons par ailleurs les enjeux méthodologiques inhérents à l’étude de ces enquêtés particuliers que sont les enfants.
Ethnographie du fait scolaire chez les migrants ruraux à Shanghai
Authors: Salgues Camille
Published: October 2012

Résumé La scolarisation des enfants de migrants ruraux en Chine fait aujourd’hui débat, dans le contexte d’un exode rural massif et d’une forte restriction de l’accès à la scolarité pour les nouveaux arrivants en ville. S’appuyant sur une enquête ethnographique réalisée dans un quartier dégradé aux marges de Shanghai, l’article propose une description d’une école privée pour migrants installée dans ce vide institutionnel, puis des formes que prend la scolarité au sein des familles à travers trois études de cas. La démarche s’efforce ainsi de restituer dans ses différentes facettes l’importance du fait scolaire , comme fait social, dans la vie de ces enfants. Elle s’inscrit plus généralement dans une approche durkheimienne de l’enfance et de ses institutions, qui vise à montrer que l’enfance est une dimension sociale à part entière, irréductible, de la genèse sociale des individus.
Processus de cadrage et mouvements sociaux : présentation et bilan
Authors: Benford Robert D. , Snow David A. , Plouchard Nathalie Miriam
Published: October 2012

Résumé Ce texte est la traduction d’un article devenu classique sur l’analyse des cadres appliquée à la sociologie des mouvements sociaux, initialement publié par l’ Annual Review of Sociology en 2000. La récente multiplication de travaux académiques sur les cadres de l’action collective et sur les processus de cadrage liés aux mouvements sociaux permet de constater que ces processus sont désormais considérés – de même que la mobilisation des ressources et les processus d’opportunités politiques – comme une dynamique essentielle pour comprendre la nature et l’évolution des mouvements sociaux. Cet article étudie en quoi ces travaux sont utiles pour analyser et comprendre les dynamiques des mouvements sociaux. Il éclaire en premier lieu la manière dont les cadres de l’action collective ont été conceptualisés ainsi que leurs caractéristiques et leurs variables. Il examine ensuite les travaux portant sur les dynamiques et les processus de cadrage. Après cela, il étudie les travaux portant sur les différents facteurs contextuels qui contraignent ou facilitent ces processus de cadrage. En conclusion, il rend compte des conséquences de ces processus de cadrage sur les autres processus liés aux mouvements sociaux ainsi que sur leurs résultats. Ainsi cherche-t-il à clarifier les liens entre les concepts et processus en lien avec la notion de cadrage et d’autres concepts et formulations théoriques qui relèvent des mouvements sociaux, tels que les notions de schème et d’idéologie.
La canzone di Jordan Bonel S’ira d’amor tenges amic iauzen (BdT 273,1) e alcuni problemi nell’edizione critica dei testi trobadorici
Authors: Resconi Stefano
Published: October 2012

Certains traits propres à la tradition manuscrite troubadouresque – rareté des erreurs graves qui pourraient servir de guide à l'éditeur et contamination textuelle endémique – rendent pour le moins difficile l’application fidèle des principes méthodologiques lachmanniens dans l’approche critique de ce genre de textes. Dans cet article, nous proposons des procédures facilitant la reconstitution des liens généalogiques qu’entretiennent entre eux les témoins manuscrits, y compris dans les cas les plus problématiques. Ce genre de procédures repose plus précisément sur une évaluation prudente des différents types d’innovation textuelle en vue de leur intégration dans un système cohérent. Nous donnons un exemple de ces procédures à partir de l’étude de la tradition d’un des rares textes troubadouresques qui n’ait pas encore été édité de façon scientifique : S’ira d’amor tenges amic iauzen de Jordan Bonel (BdT 273,1) dont nous livrons ici pour la première fois une édition critique.
La Chronique d’Ernoul : problèmes et méthode d’édition
Authors: Gaggero Massimiliano
Published: October 2012

La Chronique d’Ernoul nous a été transmise par 54 manuscrits qui donnent plusieurs rédactions du texte. Les études précédentes sur les relations entre ces rédactions se fondaient sur un examen partiel de la tradition. Cet article a été écrit en vue de la préparation d’une nouvelle édition de la Chronique, dans le cadre du projet dirigé par P. W. Edbury et financé par l’Arts and Humanities Research Council. Les résultats de l’étude de deux échantillons de texte collationnés sur tous les manuscrits permettent de présenter pour la première fois un stemma codicum qui représente l’histoire de toute la tradition et de poser sur des bases nouvelles les problèmes de l’édition d’un texte historique transmis par plusieurs rédactions.
L’édition scientifique des documents comptables médiévaux : enjeux et perspectives d’une entreprise pluridisciplinaire
Authors: Wirth-Jaillard Aude
Published: October 2012

Bien que les documents comptables médiévaux soient particulièrement riches pour l’étude de la langue (lexique, anthroponymie, ponctuation, discours rapporté ou encore syntaxe), les éditeurs de textes, ne se préoccupant guère de représentativité linguistique, leur ont généralement préféré les textes littéraires. Pourtant, les comptes présentent un intérêt réel pour le linguiste, l’historien ou l’archéologue. Il paraît donc nécessaire de procéder à des éditions de ce type de sources selon des normes communes à l’ensemble des spécialistes du Moyen Âge, normes fondées principalement sur le respect du texte original. Ces éditions, informatisées, présenteront trois niveaux, du plus proche du texte au plus normalisé. Elles devront être l’occasion, dans leur réalisation comme dans leur exploitation, d’une interdisciplinarité effective.
L’électronique à l’aide de l’éditeur : miracle ou mirage ? Bilan de quatorze années de travaux au LFA
Authors: Kunstmann Pierre
Published: October 2012

Cet article présente d’abord un bilan de quatorze années de travaux (1997-2011) au Laboratoire de Français Ancien (LFA) de l’Université d’Ottawa. Le site internet www.lfa.uottawa.ca en constitue la fenêtre de diffusion et est structuré en deux parties : la base « Textes de Français Ancien » et la série « Textes en Liberté ». Plusieurs travaux sont menés en collaboration avec l’ATILF (CNRS, Nancy) : la « Base de Graphies Verbales », le « Dictionnaire Électronique de Chrétien de Troyes », l’édition critique électronique des Miracles de Notre-Dame par personnages. Ce site héberge également la base bibliographique ARLIMA. Ces bases textuelles constituent un apport essentiel de l’électronique à l’éditeur. Leurs vastes possibilités de recherche permettent en effet d’interroger des corpus très étendus.
Le Libro de los exemplos por ABC, recueil d’exempla du xve siècle
Authors: Darbord Bernard
Published: October 2012

Cet article présente un recueil d’exempla espagnols : le Libro de los exemplos por ABC de Clemente Sánchez de Vercial (XVe siècle). Ses sources ainsi que certains de ses principaux thèmes (l’amitié et l’aumône) y sont analysés à travers de nombreux extraits.
Le Roman de la Rose, de l’édition aux manuscrits
Authors: Frieden Philippe
Published: October 2012

De tous les textes en langue vernaculaire, le Roman de la Rose est celui dont l’histoire éditoriale est la plus complexe en raison du grand nombre de manuscrits qui l’ont transmis. Cet article tente de retracer cette histoire de la fin du Moyen Âge au xxe siècle en suivant deux pistes : d’une part celle de la langue du manuscrit (sa proximité ou son éloignement du point de naissance de l’œuvre), d’autre part celle du contenu du texte. Au fil des deux siècles de sa copie, le récit de Guillaume de Lorris et de Jean de Meun s’est vu augmenté de nombreux ajouts. L’étude d’une interpolation contenue dans quelque vingt-six manuscrits sera l’occasion de mesurer la façon dont la variance du texte médiéval a été diversement perçue et prise en compte par les éditeurs du Roman de la Rose.
Ovarian Damage during Chemotherapy in Autoimmune Diseases: Broad Health Implications beyond Fertility
Authors: Marder Wendy , Fisseha Senait , Ganser Martha A. , Somers Emily C.
Published: October 2012

Women with autoimmune diseases such as lupus, scleroderma, and vasculitis receiving cyclophosphamide for severe disease manifestations risk primary ovarian insufficiency (POI) due to gonadotoxicity of this therapy. In addition to loss of reproductive potential, POI is associated with increased risk of morbidity and mortality. Practitioners caring for women requiring gonadotoxic therapies should be familiar with long-term health implications of POI and strategies for ovarian preservation. Accumulating evidence supports the effectiveness of adjunctive gonadotropin releasing hormone analog (GnRH-a) for ovarian protection during gonadotoxic therapy in cancer and autoimmune populations. GnRH-a is less costly and invasive than assisted reproductive technologies used for achievement of future pregnancies, but is not Food and Drug Administration approved for ovarian preservation. This review focuses on POI comorbidities and strategies for mitigation of related sequelae, which can accumulate over decades of hypoesteogenism. These issues are arguably more pronounced for women with chronic autoimmune diseases, in whom superimposed POI further heightens risks of cardiovascular disease and osteoporosis. Therefore, even if future pregnancy is not desired, ovarian protection during gonadotoxic therapy should be a major goal of disease management.
Prostitutes, Pimps, and Brothels: Intermediaries, Information, and Market Structure in Prostitution Markets
Authors: Farmer Amy , Horowitz Andrew W.
Published: October 2012

Prostitution is a multi‐billion dollar, globally distributed, low‐concentration service industry that is receiving increasing attention in the economics literature. This article focuses on a widespread, but little studied, feature of this environment—the role of intermediaries (pimps or brothel owners) on market outcomes. Prostitution laws and markets are perhaps unique in that transactions between principals (prostitutes and johns) are legal in many countries, while intermediary activity (pimping) is illegal. After surveying the varying cross‐country legality of agents we develop a simple theoretical model to analyze how the presence or absence of intermediaries shifts the distribution of market surplus. We show that eliminating pimps and brothels may shift surplus in non‐obvious ways, depending on the precise function they perform and on whether equilibrium is pooling or separating across “high quality” and “low quality” market segments. The implications of alternative policy regimes (intermediaries legal or illegal) are considered.
Trade Flows, Exchange Rate Uncertainty, and Financial Depth: Evidence from 28 Emerging Countries
Authors: Caglayan Mustafa , Dahi Omar S. , Demir Firat
Published: October 2012

This article investigates the effects of real exchange rate uncertainty on manufactures exports from 28 emerging economies, representing 82% of all developing country manufactures exports, and explores the sources of heterogeneity in the uncertainty effects by controlling for the direction of trade (south‐north or south‐south), and the level of financial development of the exporting country. The empirical results show that for more than half of the countries, the uncertainty effect is unidirectional, either south‐south or south‐north, and the median impact is negative. In addition, while we find that financial development augments trade, exchange rate shocks can negate this effect. Last but not least, trade among developing economies improves export growth under exchange rate shocks.
The Monetary Policy Implications of Behavioral Asset Bubbles
Authors: Gwilym Rhys ap
Published: October 2012

I introduce behavioral asset pricing rules into a wider dynamic stochastic general equilibrium framework. Asset price bubbles emerged endogenously within the model. I find that in this model monetary policy rules that target the mispricing of the asset have a destabilizing effect; however, a monetary policy rule that targets deviations in the price of the asset from its trend can be welfare enhancing. Such a rule would also have the benefit of being straightforward to implement.
Cyanobacterial heterocyst glycolipids in cultures and environmental samples: Diversity and biomarker potential
Authors: Wörmer Lars , CirÉs Samuel , VelÁzquez David , Quesada Antonio , Hinrichs Kai-Uwe
Published: October 2012

The envelope of cyanobacterial heterocysts contains characteristic glycolipids termed heterocyst glycolipids (HGs). Six cultures of heterocyst‐forming cyanobacteria, as well as samples from 2 polar ecosystems and 12 Spanish freshwaters, were analyzed for their HG content. We tentatively identified four novel HGs in the cyanobacterial strains, including derivatives with a nonhexose sugar moiety. We observed unexpectedly diverse HG distributions in cultures, with very singular fingerprinting for Aphanizomenon aphanizomenoides and Aphanizomenon ovalisporum, thus supporting the taxonomic robustness of HGs. The analysis of HGs in environmental samples revealed even larger diversity and increased abundance of certain HGs that are minor components in cultured strains. Interpretation of HG patterns could be applied to support taxonomic characterization of the community of heterocystous cyanobacteria and to detect changes in the cyanobacterial consortia mediating N2 fixation. In addition to taxonomy, environmental factors seem to influence the biosynthesis of HGs. For example, in our studied environmental samples, temperature appears to influence the relative distribution of keto‐hexacosanol and hexacosanediols, as previously proposed for cultures. Our results extend the knowledge of HG distributions in cyanobacteria and the environment and illustrate the potential of HGs as biomarkers for applications in both ecological and paleoenvironmental studies.
Terrestrial support of zebra mussels and the Hudson River food web: A multi‐isotope, Bayesian analysis
Authors: Cole Jonathan J. , Solomon Christopher T.
Published: October 2012

The Hudson River is a strongly heterotrophic system in which the invasive zebra mussel (Dreissena polymorpha) comprises >90% of total metazoan biomass. Using a Bayesian mixing model, with isotope ratios of C, N, and H, and four basal resources (phytoplankton, benthic algae, submersed aquatic vegetation [SAV], and terrestrial inputs), we estimated the reliance of 10 consumers on each resource. Copepods, Bosmina, and herring (Alosa aestivalis) relied 40–60% on phytoplankton primary production; amphipods and young‐of‐year white perch (Morone spp.) relied heavily on benthic algae (50–60%). Terrestrial detritus was an important resource for oligochaetes, zebra mussels, chironomids, and Bosmina sp., for which median estimates of reliance were between 40% and 60%. The dual reliance of zebra mussels on terrestrial detritus and phytoplankton production, combined with their high biomass, along with the significant terrestrial support of several other consumers, indicates that terrestrial detritus supports a significant portion of the Hudson River food web. Nonetheless, given that particulate and dissolved organic matter pools are heavily dominated (60–80%) by terrestrial detritus, it is clear that selectivity by consumers for autochthonous organic matter is generally high. Despite its large biomass and productivity, we did not find strong evidence for support of the food web by SAV.
Viral lysis and microzooplankton grazing of phytoplankton throughout the Southern Ocean
Authors: Evans Claire , Brussaard Corina P. D.
Published: October 2012

We investigated microzooplankton grazing and viral lysis of the pico‐ and nanophytoplankton community in the Southern Ocean during the “Sensitivity of Sub‐Antarctic Zone Waters to Global Change” cruise to the Australian sector (January–February 2007) and the Antarctic–XXIV/3 (February–March 2008) expedition to the Greenwich Meridian and the Drake Passage. A dilution assay was employed in concert with flow cytometry at stations that spanned the sub‐Antarctic, Polar Frontal, and Antarctic Zones and in the Weddell Gyre. Both viral lysis and microzooplankton grazing played a significant role in controlling cyanobacterial populations, except in the sub‐Antarctic west of Tasmania, where their growth was regulated by grazing alone. Three main groups of eukaryotic algae were detected, and these were calculated to have average cell diameters of 0.8, 2.1, and 3.7 µm. Grazing was significant in the control of their growth at all locations, whereas viral lysis of eukaryotic algae was comparatively minor, as it was detected in only 40% of the experiments. Throughout the surveyed sites no pattern between geographical location and growth rates and/or mortality rates could be established for any of the phytoplankton groups. Estimates of iron regeneration indicated that as a result of its widespread occurrence, microzooplankton grazing is a more consistent source of regenerated iron to the Southern Ocean but that viral lysis can be responsible for significant pulses of iron into the dissolved pool.
Air-surface exchange measurements of gaseous elemental mercury over naturally enriched and background terrestrial landscapes in Australia
Authors: Edwards G. C. , Howard D. A.
Published: October 2012

Abstract. This paper presents the first gaseous elemental mercury (GEM) air-surface exchange measurements obtained over naturally enriched and background (< 0.1 μg g−1 Hg) terrestrial landscapes in Australia. Two pilot field studies were carried out during the Australian autumn and winter periods at a copper-gold-cobalt-arsenic-mercury mineral field near Pulganbar, NSW. GEM fluxes using a dynamic flux chamber approach were measured, along with controlling environmental parameters over three naturally enriched and three background substrates. The enriched sites results showed net emission to the atmosphere and a strong correlation between flux and substrate Hg concentration, with average fluxes ranging from 14 ± 1 ng m−2 h−1 to 113 ± 6 ng m−2 h−1. Measurements at background sites showed both emission and deposition. The average Hg flux from all background sites showed an overall net emission of 0.36 ± 0.06 ng m−2 h−1. Fluxes show strong relationships with temperature, radiation, and substrate parameters. A compensation point of 2.48, representative of bare soils was determined. Comparison of the Australian data to North American data confirmed the need for Australian specific mercury air-surface exchange data representative of Australia's unique climatic conditions, vegetation types, land use patterns, and soils.
SCIAMACHY lunar occultation water vapor measurements: retrieval and validation results
Authors: Azam F. , Bramstedt K. , Rozanov A. , Weigel K. , Bovensmann H. , Stiller G. P. , Burrows J. P.
Published: October 2012

Abstract. SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) lunar occultation measurements have been used to derive vertical profiles of stratospheric water vapor for the Southern Hemisphere in the near infrared (NIR) spectral range of 1350–1420 nm. The focus of this study is to present the retrieval methodology including the sensitivity studies and optimizations for the implementation of the radiative transfer model on SCIAMACHY lunar occultation measurements. The study also includes the validation of the data product with the collocated measurements from two satellite occultation instruments and two instruments measuring in limb geometry. The SCIAMACHY lunar occultation water vapor measurement comparisons with the ACE-FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) instrument have shown an agreement of 5% on the average that is well within the reported biases of ACE in the stratosphere. The comparisons with HALOE (Halogen Occultation Experiment) have also shown good results where the agreement between the instruments is within 5%. The validations of the lunar occultation water vapor measurements with MLS (Microwave Limb Sounder) instrument are exceptionally good, varying between 1.5 to around 4%. The validations with MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) are in the range of 10%. A validated dataset of water vapor vertical distributions from SCIAMACHY lunar occultation measurements is expected to facilitate the understanding of physical and chemical processes in the southern mid-latitudes and the dynamical processes related to the polar vortex.