Novel Topology for Four-Quadrant Converter

Particle accelerators, like the LHC (Large Hadron Collider), make use of true bipolar power converters to feed superconducting magnets. Moreover, the LHC imposes that most converters must be installed underground. This constraint leads to the necessity of a high efficiency and a reduced volume for all the power converters. In this paper, the authors present a novel four-quadrant topology composed by an association of a ZVS-inverter and a ZCS-rectifier. This DC-AC-DC converter is fully reversible and a soft-switching operation mode is achieved for all switches over the full operating range. After a thorough analysis of the prototype design [±600A, ±10V], simulation and experimental results confirm the general performance of this power structure

Stendhal au Salon de 1824 : pour une manière brève dans la peinture

Stendhal importe au Salon de peinture son combat pour le romanticisme. Le corollaire de cette transposition est la promotion d’une forme brève, et d’une esthétique de la brièveté. Cette manière brève de la peinture se définit par le petit format, la concision, l’intensité, la simplicité et l’indétermination. Stendhal n’apprécie cependant pas la brièveté d’exécution et l’apparente négligence des tableaux romantiques, et considère que seule la perfection du dessin rend possible l’émotion esthétique

Anxiety in Second Language in Relation to Students’ Speaking Performance

Language anxiety is thought to hinder language learning, and if the learners are truly anxious in class, they are probably not fully engaged, if at all. With the help of the Foreign Language Speaking Anxiety Scale (FLSAS) and a free-speaking exercise, this study intends to ascertain the association between language anxiety and speaking performance among undergraduate and graduate students. Frequency count, percent, mean, and Kruskal Wallis were used as statistical techniques to total, tabulate, and further analyze and interpret scores. An extensive, unstructured phenomenological interview with the students was undertaken to ascertain the causes of their language anxiety, and the thematic analysis was carried out using Giorgi's phenomenological method. Students did less satisfactorily in speaking performances and were found to be moderately worried. Language anxiety and speaking abilities, particularly in vocabulary and comprehension, are significantly correlated. This is ascribed to error-causing factors such as the impact of the native language on the second language, lack of confidence, anxiety about communicating, and fear of being evaluated. This study concluded that speaking performance could be predicted using linguistic anxiety. Particularly in understanding and vocabulary, the worried learner frequently performed worse than the native speaker when speaking in English. According to this study, students who are really worried about language should receive training. Teachers can provide straightforward, captivating, varied, and entertaining oral tasks that will give pupils the chance to speak English freely

Anxiety in Second Language in Relation to Students’ Speaking Performance

Language anxiety is thought to hinder language learning, and if the learners are truly anxious in class, they are probably not fully engaged, if at all. With the help of the Foreign Language Speaking Anxiety Scale (FLSAS) and a free-speaking exercise, this study intends to ascertain the association between language anxiety and speaking performance among undergraduate and graduate students. Frequency count, percent, mean, and Kruskal Wallis were used as statistical techniques to total, tabulate, and further analyze and interpret scores. An extensive, unstructured phenomenological interview with the students was undertaken to ascertain the causes of their language anxiety, and the thematic analysis was carried out using Giorgi's phenomenological method. Students did less satisfactorily in speaking performances and were found to be moderately worried. Language anxiety and speaking abilities, particularly in vocabulary and comprehension, are significantly correlated. This is ascribed to error-causing factors such as the impact of the native language on the second language, lack of confidence, anxiety about communicating, and fear of being evaluated. This study concluded that speaking performance could be predicted using linguistic anxiety. Particularly in understanding and vocabulary, the worried learner frequently performed worse than the native speaker when speaking in English. According to this study, students who are really worried about language should receive training. Teachers can provide straightforward, captivating, varied, and entertaining oral tasks that will give pupils the chance to speak English freely

Undocumented Migrants in Switzerland: Geographical Origin Versus Legal Status as Risk Factor for Tuberculosis

Undocumented migrants, meaning migrants without a legal residency permit, come to Geneva from countries with high tuberculosis (TB) incidence. We estimate here whether being undocumented is a determinant of TB, independently of origin. Cross-sectional study including undocumented migrants in a TB screening program in 2002; results were compared to 12,904 age and frequency matched participants in a general TB screening program conducted at various workplaces in Geneva, Switzerland from 1992 to 2002. A total of 206 undocumented migrants (36% male, 64% female, mean age 37.8 years (SD 11.8), 82.5% from Latin America) participated in the TB screening program. Compared to legal residents, undocumented migrants had an adjusted OR for TB-related fibrotic signs of 1.7 (95% CI 0.8;3.7). The OR of TB-related fibrotic signs for Latin American (vs. other) origin was 2.7 (95% CI 1.6;4.7) among legal residents and 5.5 (95% CI 2.8;10.8) among undocumented migrants. Chest X-ray screening identified a higher proportion of TB-related fibrotic signs among Latin Americans, independently of their residency statu

Proposal of a framework for evaluating military surveillance systems for early detection of outbreaks on duty areas

<p>Abstract</p> <p>Background</p> <p>In recent years a wide variety of epidemiological surveillance systems have been developed to provide early identification of outbreaks of infectious disease. Each system has had its own strengths and weaknesses. In 2002 a Working Group of the Centers for Disease Control and Prevention (CDC) produced a framework for evaluation, which proved suitable for many public health surveillance systems. However this did not easily adapt to the military setting, where by necessity a variety of different parameters are assessed, different constraints placed on the systems, and different objectives required. This paper describes a proposed framework for evaluation of military syndromic surveillance systems designed to detect outbreaks of disease on operational deployments.</p> <p>Methods</p> <p>The new framework described in this paper was developed from the cumulative experience of British and French military syndromic surveillance systems. The methods included a general assessment framework (CDC), followed by more specific methods of conducting evaluation. These included Knowledge/Attitude/Practice surveys (KAP surveys), technical audits, ergonomic studies, simulations and multi-national exercises. A variety of military constraints required integration into the evaluation. Examples of these include the variability of geographical conditions in the field, deployment to areas without prior knowledge of naturally-occurring disease patterns, the differences in field sanitation between locations and over the length of deployment, the mobility of military forces, turnover of personnel, continuity of surveillance across different locations, integration with surveillance systems from other nations working alongside each other, compatibility with non-medical information systems, and security.</p> <p>Results</p> <p>A framework for evaluation has been developed that can be used for military surveillance systems in a staged manner consisting of initial, intermediate and final evaluations. For each stage of the process parameters for assessment have been defined and methods identified.</p> <p>Conclusion</p> <p>The combined experiences of French and British syndromic surveillance systems developed for use in deployed military forces has allowed the development of a specific evaluation framework. The tool is suitable for use by all nations who wish to evaluate syndromic surveillance in their own military forces. It could also be useful for civilian mobile systems or for national security surveillance systems.</p

Virological outcomes in ARV-naïve patients switching or not from a first successful boosted PI-regimen to efavirenz, nevirapine or abacavir regimens

International audiencen.

Beyond traditional surveillance: applying syndromic surveillance to developing settings – opportunities and challenges

<p>Abstract</p> <p>Background</p> <p>All countries need effective disease surveillance systems for early detection of outbreaks. The revised International Health Regulations [IHR], which entered into force for all 194 World Health Organization member states in 2007, have expanded traditional infectious disease notification to include surveillance for public health events of potential international importance, even if the causative agent is not yet known. However, there are no clearly established guidelines for how countries should conduct this surveillance, which types of emerging disease syndromes should be reported, nor any means for enforcement.</p> <p>Discussion</p> <p>The commonly established concept of syndromic surveillance in developed regions encompasses the use of pre-diagnostic information in a near real time fashion for further investigation for public health action. Syndromic surveillance is widely used in North America and Europe, and is typically thought of as a highly complex, technology driven automated tool for early detection of outbreaks. Nonetheless, low technology applications of syndromic surveillance are being used worldwide to augment traditional surveillance.</p> <p>Summary</p> <p>In this paper, we review examples of these novel applications in the detection of vector-borne diseases, foodborne illness, and sexually transmitted infections. We hope to demonstrate that syndromic surveillance in its basic version is a feasible and effective tool for surveillance in developing countries and may facilitate compliance with the new IHR guidelines.</p

Interaction between the GROWTH-REGULATING FACTOR and KNOTTED1-LIKE HOMEOBOX families of transcription factors

KNOTTED1-LIKE HOMEOBOX (KNOX) genes are important regulators of meristem function, and a complex network of transcription factors ensures tight control of their expression. Here, we show that members of the GROWTH-REGULATING FACTOR (GRF) family act as players in this network. A yeast (Saccharomyces cerevisiae) one-hybrid screen with the upstream sequence of the KNOX gene Oskn2 from rice (Oryza sativa) resulted in isolation of OsGRF3 and OsGRF10. Specific binding to a region in the untranslated leader sequence of Oskn2 was confirmed by yeast and in vitro binding assays. ProOskn2:β-glucuronidase reporter expression was down-regulated by OsGRF3 and OsGRF10 in vivo, suggesting that these proteins function as transcriptional repressors. Likewise, we found that the GRF protein BGRF1 from barley (Hordeum vulgare) could act as a repressor on an intron sequence in the KNOX gene Hooded/Barley Knotted3 (Bkn3) and that AtGRF4, AtGRF5, and AtGRF6 from Arabidopsis (Arabidopsis thaliana) could repress KNOTTED-LIKE FROM ARABIDOPSIS THALIANA2 (KNAT2) promoter activity. OsGRF overexpression phenotypes in rice were consistent with aberrant meristematic activity, showing reduced formation of tillers and internodes and extensive adventitious root/shoot formation on nodes. These effects were associated with down-regulation of endogenous Oskn2 expression by OsGRF3. Conversely, RNA interference silencing of OsGRF3, OsGRF4, and OsGRF5 resulted in dwarfism, delayed growth and inflorescence formation, and up-regulation of Oskn2. These data demonstrate conserved interactions between the GRF and KNOX families of transcription factors in both monocot and dicot plants