bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors
Authors: Brandão Sâmia de Freitas , Campos Tarcísio Passos Ribeiro de
Published: December 2013

Objective Comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and Methods Simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results Intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h-1.p-1.s, respectively, on the healthy tissue, on the balloon periphery and on the I 1 and I 2 tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h-1.p-1.s, respectively on the healthy tissue, on the target tumor and on the I 1 and I 2 infiltration zones. Conclusion Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones.
Mucinous carcinoma of the breast: iconographic essay with histopathological correlation
Authors: Coeli Gustavo Nunes Medina , Reis Henrique Ferreira dos , Bertinetti Dayse Ribeiro , Faria Francesca Maia , Tiezzi Daniel Guimarães , Oliveira Tatiane Mendes Gonçalves de
Published: December 2013

The present essay is aimed at describing the most characteristic imaging findings of mucinous carcinoma of the breast, with emphasis on the patterns related to better prognosis. The authors selected cases of mucinous carcinoma of the breast whose images were available, highlighting the imaging findings suggestive of this subtype of breast cancer, either at mammography, ultrasonography or magnetic resonance imaging.
Imaging evaluation of middle ear cholesteatoma: iconographic essay
Authors: Ávila Ana Flávia Assis de , Aburjeli Bruna de Oliveira Melim , Moreira Wanderval , Motta Emília Guerra Pinto Coelho , Ribeiro Marcelo Almeida , Diniz Renata Lopes Furletti Caldeira
Published: December 2013

Middle ear cholesteatoma is a relevant and relatively common disease that may have severe consequences. In the present pictorial essay, the authors have selected illustrative examples of multislice computed tomography and magnetic resonance imaging depicting the main presentations of cholesteatomas, and describing their characteristics, locations, and major complications.
Giant cell tumor of the frontal sinus: case report
Authors: Matushita João Paulo , Matushita Julieta S. , Simões Luiz Antonio Monteiro , Carvalho Neto Lizando Franco de , Matushita Cristina S. , Matushita Junior João Paulo Kawaoka
Published: December 2013

The authors report the case of a giant cell tumor of the frontal sinus in a 54-year-old male patient. This tumor location is rare, and this is the third case reported in the literature with radiographic documentation and histopathological confirmation. The patient underwent surgery, with curettage of frontal sinus and placement of a prosthesis. He died because a voluntary abrupt discontinuation of corticosteroids.
A microwave approach to the synthesis of certain 4-substituted phenyl-6-phenyl-3-cyano-2-pyridones
Authors: Marinkovic Aleksandar , Mijin Dusan , Mirkovic Jelena , Maslak Veselin , Kappe Oliver
Published: December 2013

A study of the synthesis of 4-substituted phenyl-6-phenyl-3-cyano-2-pyridones
from 2-cyano-3-phenylsubstituted acrylates and acetophenone is presented.
2-Pyridones were obtained using conventional as well as microwave synthesis
using solvent and solvent free reactions in domestic and lab microwave ovens.
The structure of the obtained pyridones was confirmed by m.p., FT-IR, NMR and
UV data.
Democratizing Classroom Discourse: The Challenge for Online Writing Environments
Authors: Kline Sonia , Letofsky Kirsten , Woodard Rebecca
Published: November 2013

This article is intended to highlight peer response discourse trends and to initiate a dialogue about the ways in which educators, and designers of educational environments, can play a central role in creating more democratic discourse in classrooms. We report on a research and development project involving education experts, computer engineers, assessment specialists and, most importantly, the teachers and students who inform our work. We share findings about the general discourse patterns of students from six eighth-grade classes as they use the peer feedback component of our developing online writing environment. We also examine multiple responses from one teacher's classroom. We argue that new online environments offer great potential for reimaging classroom discourse (e.g. less teacher-directed and more horizontally distributed). However, our research in this developing environment indicates that students in very different contexts respond to each other in somewhat ‘typical’ ways (e.g. they rarely elicit and offer few change strategies). Furthermore, teachers' initiating texts (e.g. assignments and rubrics) influence student discourse, often in unintentional ways that restrict student voices. Finally, we discuss implications of our work and offer a number of key recommendations for educators and designers working to promote more horizontal (peer-to-peer) discourse.
Yeast ABC proteins involved in multidrug resistance
Authors: Piecuch Agata , Obłąk Ewa
Published: December 2013

Pleiotropic drug resistance is a complex phenomenon that involves many proteins that together create a network. One of the common mechanisms of multidrug resistance in eukaryotic cells is the active efflux of a broad range of xenobiotics through ATP-binding cassette (ABC) transporters. Saccharomyces cerevisiae is often used as a model to study such activity because of the functional and structural similarities of its ABC transporters to mammalian ones. Numerous ABC transporters are found in humans and some are associated with the resistance of tumors to chemotherapeutics. Efflux pump modulators that change the activity of ABC proteins are the most promising candidate drugs to overcome such resistance. These modulators can be chemically synthesized or isolated from natural sources (e.g., plant alkaloids) and might also be used in the treatment of fungal infections. There are several generations of synthetic modulators that differ in specificity, toxicity and effectiveness, and are often used for other clinical effects.
Greenhouse Evaluation of Section Arachis Wild Species for Sclerotinia Blight and Cylindrocladium Black Rot Resistance
Authors: Tallury S. P. , Hollowell J. E. , Isleib T. G. , Stalker H. T.
Published: December 2013

Wild Arachis species from section Arachis have been promoted as sources of resistance to common peanut diseases and insect pests. The objective of our study was to identify wild Arachis species with resistance to Sclerotinia blight and Cylindrocladium black rot (CBR). One hundred and ten accessions/entries from 23 Arachis species including A. hypogaea were evaluated in the greenhouses at North Carolina State University between January and March of 2010 in a 11×10 rectangular lattice experimental design with 4 replications for Sclerotinia blight and 6 replications for CBR. For the Sclerotinia blight test, seeds were planted in 10 cm clay pots and 8-wk-old plants were inoculated in a mist chamber with BEEM capsules containing the fungus inserted on the petioles of the 4th leaf from the apex on the primary branch. Lesion lengths were measured 4, 5, 6, and 7 d after inoculation, and areas under the disease progress curves (AUDPC) were calculated. For the CBR test, seeds were planted in soil mixed with microsclerotia (25/g) in cone-tainers partly immersed in water. Root damage was recorded after 60 d on a 0–5 proportional scale (0 = no decay to 5 = completely decayed). Data analysis indicated significant (p<0.05) variation among and within Arachis species for both diseases. Arachis glandulifera exhibited the highest level of Sclerotinia blight resistance followed by A. correntina, A. herzogii, and A. helodes, although the last three species were not significantly different from A. hypogaea. Overall, low genetic variability for Sclerotinia blight resistance was observed among the wild species accessions. For CBR, A. valida, A. cruziana, A. microsperma, A. williamsii, A. kempff-mercadoi, A. kuhlmannii, A. helodes, A. cardenasii and A. correntina formed the most resistant group with A. hypogaea in the most susceptible group. Overall, significant genetic variability for CBR resistance was found among the different wild species accessions. However, not all accessions within a species were resistant to either disease, and most accessions that were resistant to one disease were susceptible to the other.
Hypsometry and sensitivity of the mass balance to changes in equilibrium-line altitude: the case of the Southern Patagonia Icefield
Authors: De Angelis Hernán
Published: November 2013

We study the relation between glacier hypsometry and sensitivity of mass-balance rate to changes in equilibrium-line altitude (ELA) to assess whether hypsometry can reliably be used to estimate the sensitivity of unmeasured glaciers to changes in ELA. We express the sensitivity of mass-balance rate to ELA, dḂ/ dELA, as a function of accumulation–area ratio (AAR), its derivative against altitude, dAAR/dELA, and mass-balance functions of ELA. We then apply the concept to 139 glaciers in the Southern Patagonia Icefield for which we derive hypsometry and AAR, and analyze the influence of hypsometry on their mass-balance rate sensitivity. We confirm that glaciers where the bulk of area is located above (below) the ELA are the least (most) sensitive. Glaciers with unimodal hypsometric curves where the peak of area fraction is around the present ELA, and glaciers with bi-or multimodal area distributions, with the ELA located approximately between the bulges, have intermediate sensitivities. We conclude that hypsometry can be used as a first-order estimator of mass-balance rate sensitivity to ELA change.
Laparoscopic Evaluation of Pelvic Organs In Case of Infertility
Authors: Maherunnessa - , Chowdhury TA , Jahan Samsad , Begum Nurunnahar , Sultana Samina , Rumman Umme
Published: December 2013

Objective: Evaluation of pelvic organs by laparoscopy in infertile patient. Background: Despite of absence of any known risk factor for infertility various studies indicate that there may be abnormalities in pelvic organ in about two-third of the cases, as evidenced by laparoscopic study. Present study was done to have an idea about the problem in a group of patients reporting to specialised centre. Materials and Methods: It was a prospective study which was undertaken in Gynaecology and Obstetric Department at BIRDEM during the period of January 2001 to December 2001. Results: The study group comprised 100 cases of infertile patients of age between 20 to 40 years. Sixty seven percent patients had primary infertility and 33% patients had secondary infertility. Size and shape of uterus was normal in 76% cases and bicornuate uterus was found in 2% cases. Right ovary was normal in 51%patient and left ovary was normal in 53%. Polycystic changes of right ovary were observed in 23% and of left ovary in 22% cases . Right fallopian tube was normal in 71% and left fallopian tube was normal in 69% cases. Patency of right fallopian tube was found in 89%and patency of left fallopian tube was found in 90%. Eleven percent patients were found to have peritubal adhesion on right side and 10% on left side. Pouch of Douglas was found to be normal in 69% cases and 9% cases had adhesion with obliteration. Conclusion: Laparoscopy is an important tool for diagnosing anatomical and pathological abnormalities of internal genital organs which plays a major role in infertility management. For treating infertility, we should give appropriate importance on laparoscopic evaluation of pelvic organs. Birdem Med J 2013; 3(2): 90-93 DOI: http://dx.doi.org/10.3329/birdem.v3i2.17212
A Rare Case of Adrenocortical Carcinoma
Authors: Afsana Faria , Latif Zafar Ahmed , Pathan Md. Faruque
Published: December 2013

A 15 year old girl was admitted with absence of menstruation and increase growth of facial and body hair for two years along with change of voice for six months. With these complaint, tablet progesterone was advised but there was no withdrawal bleeding. On examination she had hirsuitism. She had normal female secondary sex characteristics with mild clitoromegaly. Her investigations revealed hyperandrogenemia with normal level of other adrenal hormones. Imaging revealed left adrenal mass. Left adrenalectomy done and histopathology revealed malignant tumor of Zona reticularis. Adrenocortical carcinoma is a rare tumor and only limited information is available about its natural history and the effects of therapy. The case is a rare androgen producing malignant tumor of adrenal having an earlier age of presentation. Birdem Med J 2013; 3(2): 110-112 DOI: http://dx.doi.org/10.3329/birdem.v3i2.17216
Forest Typification to Characterize the Structure and Composition of Old-growth Evergreen Forests on Chiloe Island, North Patagonia (Chile)
Authors: Bannister Jan , Donoso Pablo
Published: November 2013

The Evergreen forest type develops along the Valdivian and North-Patagonian phytogeographical regions of the south-central part of Chile (38° S–46° S). These evergreen forests have been scarcely studied south of 43° S, where there is still a large area made up of old-growth forests. Silvicultural proposals for the Evergreen forest type have been based on northern Evergreen forests, so that the characterization of the structure and composition of southern Evergreen forests, e.g., their typification, would aid in the development of appropriate silvicultural proposals for these forests. Based on the tree composition of 46 sampled plots in old-growth forests in an area of >1000 ha in southern Chiloé Island (43° S), we used multivariate analyses to define forest groups and to compare these forests with other evergreen forests throughout the Archipelago of North-Patagonia. We determined that evergreen forests of southern Chiloé correspond to the North-Patagonian temperate rainforests that are characterized by few tree species of different shade tolerance growing on fragile soils. We discuss the convenience of developing continuous cover forest management for these forests, rather than selective cuts or even-aged management that is proposed in the current legislation. This study is a contribution to forest classification for both ecologically- and forestry-oriented purposes.
Role of Sam68 in Post-Transcriptional Gene Regulation
Authors: Sánchez-Jiménez Flora , Sánchez-Margalet Víctor
Published: November 2013

The STAR family of proteins links signaling pathways to various aspects of post-transcriptional regulation and processing of RNAs. Sam68 belongs to this class of heteronuclear ribonucleoprotein particle K (hnRNP K) homology (KH) single domain-containing family of RNA-binding proteins that also contains some domains predicted to bind critical components in signal transduction pathways. In response to phosphorylation and other post-transcriptional modifications, Sam68 has been shown to have the ability to link signal transduction pathways to downstream effects regulating RNA metabolism, including transcription, alternative splicing or RNA transport. In addition to its function as a docking protein in some signaling pathways, this prototypic STAR protein has been identified to have a nuclear localization and to take part in the formation of both nuclear and cytosolic multi-molecular complexes such as Sam68 nuclear bodies and stress granules. Coupling with other proteins and RNA targets, Sam68 may play a role in the regulation of differential expression and mRNA processing and translation according to internal and external signals, thus mediating important physiological functions, such as cell death, proliferation or cell differentiation.
Bone Morphogenetic Protein-7 Ameliorates Cerebral Ischemia and Reperfusion Injury via Inhibiting Oxidative Stress and Neuronal Apoptosis
Authors: Pei Haitao , Cao Dongming , Guo Zhuangli , Liu Guofang , Guo Yunliang , Lu Chenglong
Published: November 2013

Previous studies have indicated that bone morphogenetic protein-7 (BMP-7) is neuroprotective against cerebral ischemia/reperfusion (IR) injury. The present study was undertaken to determine the molecular mechanisms involved in this effect. Adult male Wistar rats were subjected to 2 h of transient middle cerebral artery occlusion (MCAO), followed by 24 h of reperfusion. BMP-7 (10−4 g/kg) or vehicle was infused into rats at the onset of reperfusion via the tail vein. Neurological deficits, infarct volume, histopathological changes, oxidative stress-related biochemical parameters, neuronal apoptosis, and apoptosis-related proteins were assessed. BMP-7 significantly improved neurological and histological deficits, reduced the infarct volume, and decreased apoptotic cells after cerebral ischemia. BMP-7 also markedly enhanced the activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), and reduced the level of malondialdehyde (MDA) in IR rats. In addition, Western blot analysis indicated that BMP-7 prevented cytochrome c release, inhibited activation of caspase-3, caspase-9 and caspase-8. Our data suggested that BMP-7 has protective effects against cerebral IR injury in rats, and the neuroprotective effects may be attributed to attenuating oxidative stress and inhibiting neuronal apoptosis.
Genetic Diversity and Conservation of the Prespa Trout in the Balkans
Authors: Berrebi Patrick , Tougard Christelle , Dubois Sophie , Shao Zhaojun , Koutseri Irene , Petkovski Svetozar , Crivelli Alain
Published: November 2013

The Balkans are known to have a high level of biodiversity and endemism. No less than 15 taxa have been recorded in salmonids of the Salmo genus. Among them, the Prespa trout is found in only four river systems flowing into Lake Macro Prespa, three in the Former Yugoslav Republic of Macedonia and one in Greece. This is the first comprehensive survey of all streams located within the Macro Prespa Basin, encompassing the whole taxon range. A large genetic sample of 536 Prespa trout was collected mainly between 2005 and 2007. The sampling included 59 individuals from the Golema river system, 93 from the Kranska, 260 from the Brajcinska, 119 from the Agios Germanos, and five individuals from the lake itself. These specimens were analyzed with six microsatellite markers and by sequencing the mitochondrial control region. Nuclear data were examined through multidimensional analysis and assignment tests. Five clusters were detected by assignment: Golema, Kranska, Brajcinska upstream, Rzanska Brajcinska tributary and Brajcinska downstream. Most of these river systems thus hosted differentiated Prespa trout populations (with past gene flows likely dating before the construction of dams), except Agios Germanos, which was found to be composed of 5% to 32% of each cluster. Among the five trout individuals from the lake, four originated from Kranska River and one was admixed. Supported parsimonious hypotheses are proposed to explain these specificities. Conservation of this endemic taxon should take these results into account. No translocation should be performed between different tributaries of the lake and preservation of the Brajcinska populations should address the upstream-downstream differentiation described.
Transcriptional Profiling of Hilar Nodes from Pigs after Experimental Infection with Actinobacillus Pleuropneumoniae
Authors: Yu Shumin , Zuo Zhicai , Cui Hengmin , Li Mingzhou , Peng Xi , Zhu Ling , Zhang Ming , Li Xuewei , Xu Zhiwen , Gan Meng , Deng Junliang , Fang Jing , Ma Jideng , Su Shengqun , Wang Ya , Shen Liuhong , Ma Xiaoping , Ren Zhihua , Wu Bangyuan , Hu Yanchun
Published: December 2013

The gram-negative bacterium Actinobacillus pleuropneumoniae (APP) is an inhabitant of the porcine upper respiratory tract and the causative agent of porcine pleuropneumonia (PP). In recent years, knowledge about the proinflammatory cytokine and chemokine gene expression that occurs in lung and lymph node of the APP-infected swine has been advanced. However, systematic gene expression profiles on hilar nodes from pigs after infection with Actinobacillus pleuropneumoniae have not yet been reported. The transcriptional responses were studied in hilar nodes (HN) from swine experimentally infected with APP and the control groupusing Agilent Porcine Genechip, including 43,603 probe sets. 9,517 transcripts were identified as differentially expressed (DE) at the p ≤ 0.01 level by comparing the log2 (normalized signal) of the two groups named treatment group (TG) and controls (CG). Eight hundred and fifteen of these DE transcripts were annotated as pig genes in the GenBank database (DB). Two hundred and seventy-two biological process categories (BP), 75 cellular components and 171 molecular functions were substantially altered in the TG compared to CG. Many BP were involved in host immune responses (i.e., signaling, signal transmission, signal transduction, response to stimulus, oxidation reduction, response to stress, immune system process, signaling pathway, immune response, cell surface receptor linked signaling pathway). Seven DE gene pathways (VEGF signaling pathway, Long-term potentiation, Ribosome, Asthma, Allograft rejection, Type I diabetes mellitus and Cardiac muscle contraction) and statistically significant associations with host responses were affected. Many cytokines (including NRAS, PI3K, MAPK14, CaM, HSP27, protein phosphatase 3, catalytic subunit and alpha isoform), mediating the proliferation and migration of endothelial cells and promoting survival and vascular permeability, were activated in TG, whilst many immunomodulatory cytokines were suppressed. The significant changes in the expression patterns of the genes, GO terms, and pathways, led to a decrease of antigenic peptides with antigen presenting cells presented to T lymphocytes via the major histocompatibility complex, and alleviated immune response induced APP of HN. The immune response ability of HN in the APP-infected pigs was weakened; however, cell proliferation and migration ability was enhanced.
Room Temperature Co-Precipitation Synthesis of Magnetite Nanoparticles in a Large pH Window with Different Bases
Authors: Mascolo Maria , Pei Yongbing , Ring Terry
Published: November 2013

Magnetite nanoparticles (Fe3O4) represent the most promising materials in medical applications. To favor high-drug or enzyme loading on the nanoparticles, they are incorporated into mesoporous materials to form a hybrid support with the consequent reduction of magnetization saturation. The direct synthesis of mesoporous structures appears to be of interest. To this end, magnetite nanoparticles have been synthesized using a one pot co-precipitation reaction at room temperature in the presence of different bases, such as NaOH, KOH or (C2H5)4NOH. Magnetite shows characteristics of superparamagnetism at room temperature and a saturation magnetization (Ms) value depending on both the crystal size and the degree of agglomeration of individual nanoparticles. Such agglomeration appears to be responsible for the formation of mesoporous structures, which are affected by the pH, the nature of alkali, the slow or fast addition of alkaline solution and the drying modality of synthesized powders.
A Level-Set Based Representative Volume Element Generator and XFEM Simulations for Textile and 3D-Reinforced Composites
Authors: Sonon Bernard , Massart Thierry
Published: November 2013

This contribution presents a new framework for the computational homogenization of the mechanical properties of textile reinforced composites. A critical point in such computational procedures is the definition and discretization of realistic representative volume elements (RVEs). A geometrically-based weave generator has been developed to produce realistic geometrical configurations of the reinforcing textile. This generator takes into account the contact conditions between the yarns in the reinforcement by means of an iterative scheme, accommodating the tension in the yarns in an implicit manner. The shape of the cross sections of the yarns can also be adapted as a function of the contact conditions using a level set-based post-processor. This allows a seamless transition towards an extended finite element (XFE) scheme, in which the obtained reinforcement geometry is subsequently exploited to derive the mechanical properties of the composite system using computational homogenization.
Examination of the Potential for Adaptive Chirality of the Nitrogen Chiral Center in Aza-Aspartame
Authors: Bouayad-Gervais Samir , Lubell William
Published: November 2013

The potential for dynamic chirality of an azapeptide nitrogen was examined by substitution of nitrogen for the α-carbon of the aspartate residue in the sweetener S,S-aspartame. Considering that S,S- and R,S-aspartame possess sweet and bitter tastes, respectively, a bitter-sweet taste of aza-aspartame 9 could be indicative of a low isomerization barrier for nitrogen chirality inter-conversion. Aza-aspartame 9 was synthesized by a combination of hydrazine and peptide chemistry. Crystallization of 9 indicated a R,S-configuration in the solid state; however, the aza-residue chiral center was considerably flattened relative to its natural amino acid counterpart. On tasting, the authors considered aza-aspartame 9 to be slightly bitter or tasteless. The lack of bitter sweet taste of aza-aspartame 9 may be due to flattening from sp2 hybridization in the urea as well as a high barrier for sp3 nitrogen inter-conversion, both of which may interfere with recognition by taste receptors.
New Short Strategy for the Synthesis of the Dibenz[b,f]oxepin Scaffold
Authors: Moreno David , Giorgi Giorgio , Salas Cristian , Tapia Ricardo
Published: December 2013

In this report a short and efficient synthesis of the dibenz[b,f]oxepin framework through intramolecular SNAr and McMurry reactions is described. The diaryl ethers required for the McMurry reaction have been obtained in good yields under microwave-assisted conditions of the reaction of salicylaldehydes with fluorobenzaldehydes without catalysts. Application of an intramolecular McMurry reaction to the synthesized diarylethers using TiCl4/Zn in THF gave the target dibenzo[b,f]oxepin system in 53%–55% yields.
Antimicrobial Peptides
Authors: Bahar Ali , Ren Dacheng
Published: November 2013

The rapid increase in drug-resistant infections has presented a serious challenge to antimicrobial therapies. The failure of the most potent antibiotics to kill “superbugs” emphasizes the urgent need to develop other control agents. Here we review the history and new development of antimicrobial peptides (AMPs), a growing class of natural and synthetic peptides with a wide spectrum of targets including viruses, bacteria, fungi, and parasites. We summarize the major types of AMPs, their modes of action, and the common mechanisms of AMP resistance. In addition, we discuss the principles for designing effective AMPs and the potential of using AMPs to control biofilms (multicellular structures of bacteria embedded in extracellular matrixes) and persister cells (dormant phenotypic variants of bacterial cells that are highly tolerant to antibiotics).
Instability of Contact Resistance in MEMS and NEMS DC Switches under Low Force: the Role of Alien Films on the Contact Surface
Authors: Qiu Haodong , Wang Hong , Ke Feixiang
Published: November 2013

The metal contact is one of the most crucial parts in ohmic-contact microelectromechanical (MEMS) switches, as it determines the device performance and reliability. It has been observed that there is contact instability when the contact force is below a threshold value (minimum contact force). However, there has been very limited knowledge so far about the unstable electrical contact behavior under low contact force. In this work, the instability of Au-Au micro/nano-contact behavior during the initial stage of contact formation is comprehensively investigated for the first time. It has been found that the alien film on the contact surface plays a critical role in determining the contact behavior at the initial contact stage under low contact force. A strong correlation between contact resistance fluctuation at the initial contact stage and the presence of a hydrocarbon alien film on the contact surface is revealed. The enhancement of contact instability due to the alien film can be explained within a framework of trap-assisted tunneling.
Le bâtiment de la « Vieille Manécanterie » de la cathédrale Saint-Jean de Lyon
Authors: Vialettes Madeleine
Published: November 2013

The edifice of the « Vieille Manécanterie » in the precincts of the cathedral of Saint Jean at Lyon, by Madeleine Vialettes.

At Lyon, the edifice called the « Vieille Manécanterie », together with the west gallery of the gothic cloister, is the last medieval vestige of the canons' cloister attached to the cathedral of Saint Jean. No archival document prior to the twelfth century designates this building with any precision ; in that century, however, it first appears as a 'refectory', then as 'dapiferie', in other words a room where the canons took their common meals. In the fourteenth century, choir boys of the cathedral were lodged here, whence the name « Manécanterie » (mane cantare) which has subsisted until the present. The rich romanesque decoration of its west façade, which is a prolongation the façade of the cathedral, contrasts with the sobriety of its south wall. A great arch, six meters wide, constructed with alternating stone and brick voussoirs opens at the base of this wall. Limited excavations under the floor level have exposed the western Springer, console and engaged pier of the arch, but when the subsoil was turned neither the original floor level of the arch, nor any archeological material contemporary to its construction were found. Dating of the brick voussoirs by magnetic remanence suggests that the arch is a vestige of an episcopal palace or canon 's residence built by Léidrade, bishop of Lyon during the reign of Charlemagne, who, in a letter addressed to the emperor in 810, mentioned such buildings, without localizing them.
Saint-Germain-des-Prés, les ambitions de la sculpture de la nef romane
Authors: Sandron Dany
Published: November 2013

Saint-Germain-des-Prés. Les ambitions de la sculpture de la nef romane.

Le thème de l'Eucharistie tient une place prépondérante dans le décor sculpté de la nef de Saint-Germain-des-Prés. Sur deux chapiteaux conservés au musée national du Moyen Âge figurent le Christ en Majesté tenant l'ostie dans la main droite, et deux prêtres élevant un calice et une ostie vers une troisième figure centrale qui pourrait être encore le Christ. Cette insistance peut être mise en rapport avec la controverse eucharistique qui agita l'Église au XIe siècle, autour notamment de la personne de Béranger, écolâtre de Tours, qui rejetait la conversion substantielle du pain et du vin et la Présence réelle.

La sculpture des chapiteaux pourrait traduire l'engagement de l'abbaye dans le débat théologique du moment. L'abbé Adélard disciple de Guillaume de Volpiano qui avait réformé l'établissement, était proche du roi Henri Ier soucieux de défendre l'orthodoxie. Un concile se tint d'ailleurs à Paris en 1050 sur l'initiative royale pour examiner cette question.

Dans l'ébauche de programme qui unit ces chapiteaux et quelques autres, les références à l'époque carolingienne, témoin des premières controverses eucharistiques, touchent à la fois l'iconographie et le style. Les mêmes tendances caractérisent l'activité du scriptorium de Saint-Germain vers le milieu du XIe siècle. Il faut sans doute y voir des preuves conjointes du renouveau d'une communauté réformée qui exploite un passé glorieux pour retrouver son rang.
Multiple Plantago species (Plantaginaceae) modify floral reflectance and color in response to thermal change
Authors: Anderson Erin R. , Lovin Mary E. , Richter Scott J. , Lacey Elizabeth P.
Published: November 2013

• Premise of the study: Understanding how plant reproduction responds to temperature has become increasingly important because of global climate change. Temperature‐sensitive plasticity in floral reflectance is likely involved in some of these responses. Such plasticity, which underlies thermoregulatory ability, affects reproductive success in Plantago lanceolata. To see whether other Plantago species also show thermal plasticity in reflectance, we measured plasticity in P. lagopus, P. coronopus, P. major, P. subulata, P. albicans, P. tomentosa, P. maritima, and P. weldenii.

• Methods: We induced plants to flower at two temperatures in growth chambers and recorded floral reflectance (362–800 nm).

• Key results: All species were thermally plastic in visible and near‐IR regions. Species and populations differed in response. Some showed greater variation in reflectance at warm temperature, while the reverse was true for others. Plasticity was greatest in the P. lanceolata clade. Cosmopolitan species were not more plastic than were geographically restricted species.

• Conclusions: The data suggest that (1) thermal plasticity is an ancestral trait for Plantago, (2) plasticities in visible and near‐IR regions have evolved along different pathways within the genus, and (3) phylogenetic history partially explains this evolutionary divergence. Our data combined with those of previous studies suggest that global climate change will modify floral reflectance and color in many plant species. These modifications are likely to affect plant reproductive success.
Troubles d'apprentissage de la lecture : rôle des facteurs cognitifs, comportementaux et socio-économiques
Authors: Fluss Joel , Bertrand Daisy , Ziegler Johannes , Billard Catherine
Published: December 2013

Résumé Les difficultés en lecture font partie des troubles d’apprentissage les plus importants durant l’enfance. Le but de notre recherche est d’étudier les facteurs biologiques, socio-économiques, cognitifs et comportementaux sous-jacents aux troubles d’acquisition de la lecture chez les élèves de CE1 français. Mille soixante-deux enfants répartis dans 20 écoles différentes de la ville de Paris ont pris part à cette recherche. A l’issue d’une première phase de dépistage, les enfants suspectés de trouble d’apprentissage de la lecture ont été testés individuellement. Par la suite, 100 faibles lecteurs et 50 normo-lecteurs ont été appariés sur la base de leur âge, leur sexe, leur école et leur environnement socio-économique. Pour chacun, un bilan médical, cognitif et comportemental a été réalisé, complété par des données socio-économiques personnelles. Dans notre échantillon, la prévalence moyenne des troubles d’apprentissage de la lecture est d’environ 12 %. Ce taux est fortement influencé par l’environnement socio-économique et varie de 3,3 % dans les milieux socio-économiques favorisés à 24,2 % dans les milieux socio-économiques défavorisés. Parmi les indicateurs familiaux du niveau socio-économique, le niveau d’éducation de la mère permet de distinguer les faibles lecteurs des normo-lecteurs. Les régressions multiples mettent en évidence que la conscience phonologique et l’inattention restent cependant les deux facteurs qui prédisent le mieux les performances en lecture de l’élève.
Apport de la neuropsychologie au bilan et à la revalidation d'un cas de dysphasie développementale de type mnésique
Authors: Walch Jean-Pierre , Bon Valérie
Published: December 2013

Résumé Le présent article vise à illustrer l’apport d’une démarche neuropsychologique au bilan et à l’approche soignante d’un cas de dysphasie développementale de type mnésique. Les auteurs s’attachent tout d’abord à éclairer l’impact diagnostique du bilan neuropsychologique, dans le contexte d’interface inhérent à cette discipline ainsi qu’aux conceptions actuelles du langage oral. Le bilan neuropsychologique est ainsi situé par rapport à un instantané des autres données, ici principalement orthophoniques, recueillies. Ce document insiste ensuite largement et de façon concrète sur les aspects rééducatifs. L’étude de cas est présentée selon un axe couplant diagnostic, pratique rééducative et données évolutives. Une large illustration du programme de revalidation à orientation neuropsychologique réalisé à partir des réflexions synthétiques tirées du cadre nosologique utilisé est proposée. Le niveau général de validité des actions entreprises est, encore, questionné au travers de l’étude des axes évolutifs quantitatifs et qualitatifs objectivés, en lien supposé avec la réalisation du programme de revalidation. Enfin, les liens de complémentarité que la neuropsychologie entretient avec le domaine orthophonique sont abordés d’un point de vue à la fois diagnostique et soignant.
Des images aux mots : une approche des troubles spécifiques du langage à partir d'un partenariat orthophoniste/psychologue du développement
Authors: Witko Agnès , Mollat Aline
Published: December 2013

Résumé Dans le cadre des prises en charge diversifiées conçues par une équipe soignante pluridisciplinaire intervenant en Institut Thérapeutique Educatif et Pédagogique, une collaboration orthophoniste/psychologue du développement a engendré une expérience de groupe avec quatre adolescents présentant un diagnostic de troubles spécifiques du langage. Les données anamnestiques les concernant renvoient au terme de « dysphasie » et rendent compte de troubles phonologiques, point commun aux quatre tableaux langagiers. En convoquant des champs aussi divers que la psycholinguistique, les neurosciences et la neuropsychologie, la stratégie orthophonique mettra l’accent sur le contournement de l’analyse segmentale pour créer des liens entre différents formats de représentations : verbales, visuelles et conceptuelles. En complémentarité, et afin d’explorer l’intrication entre développement cognitif et langagier, la méthode clinique de remédiation cognitive prendra appui sur des schèmes logiques essentiels à l’acquisition du langage écrit tels que la composition additive, l’ordination, et la classification. Ces deux démarches coordonnées favorisent l’expression de soi et la réussite grâce à des cycles communicationnels positifs. En effet, l’utilisation de rébus et charades a permis de créer un support unificateur et ludique, ainsi qu’une entrée par l’image, vers la langue orale et écrite. Sans toutefois parvenir à caractériser précisément les stratégies compensatoires mises en œuvre par les patients, ce partenariat clinique se révèle néanmoins en faveur d’apprentissages tardifs.
Pour une pratique constructiviste de la remédiation cognitive
Authors: Paour Jean-Louis , Bailleux Christine , Perret Patrick
Published: December 2013

Résumé La remédiation cognitive est une forme de prise en charge psychologique accompagnant la construction de l’intelligence et de ses déterminants affectifs et motivationnels chez l’enfant. La première partie de l’article rappelle l’ancrage de cette pratique clinique dans l’histoire de la psychologie du développement et en spécifie les principaux fondements théoriques. La seconde partie présente les lignes organisatrices d’une approche constructiviste dans la conception et la mise en œuvre des pratiques de remédiation. Dans cette perspective, l’accent est porté sur le processus de conceptualisation, conçu comme l’un des principaux moteurs du développement de la pensée et de l’autorégulation des conduites. Une réflexion est alors engagée sur les mécanismes et les conditions qui favorisent son émergence chez l’enfant dans les dispositifs de remédiation cognitive.
Étude rétrospective du profil neuropsychologique de 33 enfants, adolescents et adultes atteints de phénylcétonurie
Authors: Canton Marie , Bonnemains Chrystèle , Monin Pierre , Feillet François
Published: December 2013

Résumé La phénylcétonurie (PCU) est la maladie héréditaire du métabolisme la plus fréquente. Elle se transmet sur le mode autosomique récessif et est liée à un déficit enzymatique entraînant l’accumulation de phénylalanine dans l’organisme, notamment au niveau cérébral. Non traitée, elle entraîne des troubles neurologiques graves et irréversibles (déficience intellectuelle, etc.). Le devenir des patients atteints de phénylcétonurie a été transformé par le dépistage néonatal systématique. En effet, le traitement, fondé sur la mise en place précoce et continue d’un régime alimentaire pauvre en phénylalanine, garantit à ces enfants un devenir cognitif normal. Cependant, des contradictions émergent de la littérature, certaines études suggérant des difficultés cognitives (exécutives). Nous avons étudié le profil neuropsychologique de 33 patients (enfants, adolescents et adultes), dépistés depuis la naissance et suivis régulièrement au niveau médical. Les résultats montrent que ces patients ont effectivement de bonnes capacités cognitives, malgré une faiblesse exécutive, notamment chez les adolescents « non compliants » au régime. Cette étude appuie ainsi l’intérêt d’une évaluation neuropsychologique comprenant une évaluation de l’efficience intellectuelle, mais aussi plus spécifiquement une évaluation des fonctions exécutives, notamment au moment de l’adolescence où les risques de non-compliance sont accrus.
Quand l'intelligence élevée fragilise la construction de l'identité : comment grandit-on quand on est surdoué ?
Authors: Siaud-Facchin Jeanne
Published: December 2013

Résumé L’adolescence du surdoué présente des particularités sur les plans intellectuel et psychodynamique essentielles à connaître pour le conduire vers un parcours de vie équilibré. Le présent article a pour objectif de montrer les spécificités de cet adolescent atypique, les points de fragilité dans sa construction identitaire, dans ses processus d’identification, dans son investissement intellectuel et scolaire qui peuvent entraîner des ruptures et des décompensations bien spécifiques qu’il faut apprendre à repérer et à accompagner. Arrivés à l’âge adulte, que deviennent les enfants surdoués ? Qui sont ceux qui parviennent à transformer leurs singularités en force de vie ? Pourquoi certains autres restent-ils sur le bord de la route et en souffrance ? Comment réussir son projet de vie avec cette « force fragile » caractéristique de cette population dont il devient urgent de tenir compte dans nos sociétés d’aujourd’hui ? Nous essaierons de répondre à ces questions à travers une approche fondée sur les connaissances psychologiques et neuroscientifiques actuelles.
La mémoire du corps chez le jeune enfant : l'impact des routines motrices sur le comportement de recherche manuelle d'objets cachés
Authors: Rivière James
Published: December 2013

Résumé Le corps a une mémoire. Il se souvient des actions motrices passées et des gestes précédemment exécutés. L’activité et l’expérience corporelles donnent en effet naissance à des traces mnésiques enracinées dans le fonctionnement de notre corps. Chez le jeune enfant en situation de recherche manuelle d’objets cachés, cette mémoire corporelle se manifeste sous la forme de routines motrices. Les travaux actuels s’accordent sur le fait qu’un ensemble complexe de facteurs entre en jeu dans la survenue chez le jeune enfant des erreurs de recherche manuelle d’objets cachés. Ils s’intéressent particulièrement à l’articulation des processus cognitifs et des contraintes perceptivo-motrices associés à ces erreurs. Des routines motrices liées à l’instauration d’un couplage perception-action sont ainsi incriminées. Nous illustrons cela via deux types d’erreur observés dans la prime enfance : l’erreur A non B, observée chez le nourrisson âgé entre 8 et 12 mois, et l’erreur C non B, observée chez l’enfant âgé de 2 ans et demi.
Troubles visuo-spatiaux de l'enfant né prématurément
Authors: Niel-Bernard Valérie
Published: December 2013

Résumé Décrite cliniquement depuis plus de 100 ans, la dyspraxie est particulièrement fréquente et présente des caractéristiques spécifiques dans la population des grands prématurés. Dans cet article, nous nous proposons de faire le point sur les travaux en cours et de dégager quelques pistes de réflexion relatives à la prévention précoce, puis nous présentons l’organisation du dépistage tel qu’il est organisé dans la région PACA Ouest – Corse du Sud par le réseau de santé Naître et Devenir.
Repérage scolaire des enfants dyslexiques en fin de primaire à l'aide de l'outil « Reperdys » : l'étude « six pour dys » en région PACA
Authors: Habib M. , Verse C. , Degremont D. , Aynaud-Szikora A. , Hervé J. , Pittaluga Mylène , Pelleing F. , Noseda-Carrière F. , Jauglard M. , Bauer C. , Bertolissio M. J. , Taudou P.
Published: December 2013

Résumé A partir de deux cohortes d’élèves de CM1 (n = 1398) et de CM2 (n = 1398) ayant bénéficié d’un repérage systématique grâce à Réperdys, un outil proposé aux enseignants en passation semi-collective, un dépistage de la dyslexie a été réalisé par les médecins scolaires des établissements concernés à l’aide d’outils spécifiques. En utilisant les critères proposés par les concepteurs de l’outil Réperdys, nous avons retrouvé un taux de repérage de 31 % pour les CM1 et autant pour les CM2, soit un taux bien supérieur à celui attendu (15 % ; Jacquier-Roux et coll., 2006). De fait, l’analyse des enfants repérés a confirmé la forte incidence de dyslexie dans les deux cohortes, respectivement 26 et 23 %, en utilisant le critère haut, c’est à dire un déficit de plus de deux écart-types par rapport à la norme. Par conséquent, environ un enfant sur quatre de la population initiale peut, d’après les critères retenus, être considéré comme potentiellement dyslexique. Les différentes explications possibles à cette surprenante constatation sont discutées. Une analyse plus détaillée des résultats a permis en outre de démontrer que l’épreuve de dictée de Réperdys était fortement corrélée à l’âge de lecture déterminé par le test de l’Alouette, alors que les deux autres épreuves (lecture de mots et copie) le sont beaucoup moins. Une analyse des erreurs en dictée, selon les critères proposés par Jacquier-Roux et coll., a montré que les erreurs dites « internes », c’est-à-dire qui enfreignent les règles de correspondance grapho-phonémique, sont significativement corrélées à l’âge de lecture, ce qui en fait un bon prédicteur du trouble de la lecture. Enfin, une analyse en composantes principales (ACP) a permis d’identifier trois facteurs de regroupement des principales mesures réalisées, validant globalement un modèle rapportant les troubles de la lecture à un déficit de nature linguistique, attentionnelle ou praxique.
L'organisation interne des énoncés : un ensemble de régulations analogiques apprises implicitement ?
Authors: Rondal Jean-Adolphe
Published: December 2013

Résumé Une conception largement répandue en psychologie du langage veut que les catégories formelles et fonctionnelles utilisées en linguistique structurale pour décrire les faits de langue aient réalité psychologique. Plusieurs arguments sont présentés à l’encontre de cette croyance. Une perspective alternative prévoit une traduction directe des rapports de sens fournis par une matrice sémantique intervenant au sein d’un cadre pragmatique, en séquences lexicales de surface. Les registres productifs se constituent par analogies substitutives apprises implicitement dans le contexte interpersonnel d’une zone proximale de développement.