Aniceto dos Reis Gonçalves Viana (1840 - 1914): o linguista em seu tempo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Cross-linking studies and membrane localization and assembly of radiolabelled large mechanosensitive ion channel (MscL) of Escherichia coli

The gene encoding the large conductance mechanosensitive ion channel (MscL) of Escherichia coli and several deletion mutants of mscL were cloned under the control of the T7 RNA polymerase promoter. Transformation of these constructs into an E. coli strain carrying an inducible T7 RNA polymerase gene allowed the specific production and labelling of MscL with [S-35]methionine. Preparation of membrane fractions of E. coli cells by sucrose gradient centrifugation indicated that the radiolabelled MscL was present in the inner cytoplasmic membrane in agreement with results of several studies. However, treatment of the labelled cells and cell membrane vesicles with various cross-linkers resulted in the majority of labelled protein migrating as a monomer with a small proportion of molecules (approximate to 25%) migrating as dimers and higher order multimers. This result is in contrast with a finding of a study suggesting that the channel exclusively forms hexamers in the cell membrane off. coli (1) and therefore may have profound implication for the activation and/or ''multimerization'' of the channel by mechanical stress exerted to the membrane. In addition, from the specific activity of the radiolabelled protein and the amount of protein in the cytoplasmic membrane fraction we estimated the number of MscL ion channels expressed under these conditions to be approximately 50 channels per single bacterium. (C) 1997 Academic Press.

Feasibility studies of the pp pi 0 e + e - electromagnetic channel at PANDA

Among all possible realizations of quark and antiquark assembly, the nucleon (the proton and the neutron) is the most stable of all hadrons and consequently has been the subject of intensive studies. Mass, shape, radius and more complex representations of its internal structure are measured since several decades using different probes. The proton (spin 1/2) is described by the electric GE and magnetic GM form factors which characterise its internal structure. The simplest way to measure the proton form factors consists in measuring the angular distribution of the electron-proton elastic scattering accessing the so-called Space-Like region where q2 < 0. Using the crossed channel antiproton proton <--> e+e-, one accesses another kinematical region, the so-called Time-Like region where q2 > 0. However, due to the antiproton proton <--> e+e- threshold q2th, only the kinematical domain q2 > q2th > 0 is available. To access the unphysical region, one may use the antiproton proton --> pi0 e+ e- reaction where the pi0 takes away a part of the system energy allowing q2 to be varied between q2th and almost 0. This thesis aims to show the feasibility of such measurements with the PANDA detector which will be installed on the new high intensity antiproton ring at the FAIR facility at Darmstadt. To describe the antiproton proton --> pi0 e+ e- reaction, a Lagrangian based approach is developed. The 5-fold differential cross section is determined and related to linear combinations of hadronic tensors. Under the assumption of one nucleon exchange, the hadronic tensors are expressed in terms of the 2 complex proton electromagnetic form factors. An extraction method which provides an access to the proton electromagnetic form factor ratio R = |GE|/|GM| and for the first time in an unpolarized experiment to the cosine of the phase difference is developed. Such measurements have never been performed in the unphysical region up to now. Extended simulations were performed to show how the ratio R and the cosine can be extracted from the positron angular distribution. Furthermore, a model is developed for the antiproton proton --> pi0 pi+ pi- background reaction considered as the most dangerous one. The background to signal cross section ratio was estimated under different cut combinations of the particle identification information from the different detectors and of the kinematic fits. The background contribution can be reduced to the percent level or even less. The corresponding signal efficiency ranges from a few % to 30%. The precision on the determination of the ratio R and of the cosine is determined using the expected counting rates via Monte Carlo method. A part of this thesis is also dedicated to more technical work with the study of the prototype of the electromagnetic calorimeter and the determination of its resolution.

Drug consumption among medical students in São Paulo, Brazil: influences of gender and academic year

OBJECTIVE: To analyze alcohol, tobacco and other drug use among medical students. METHOD: Over a five-year period (1996-2001), we evaluated 457 students at the Universidade de São Paulo School of Medicine, located in São Paulo, Brazil. The students participated by filling out an anonymous questionnaire on drug use (lifetime, previous 12 months and previous 30 days). The influence that gender and academic year have on drug use was also analyzed. RESULTS: During the study period, there was an increase in the use of illicit drugs, especially inhalants and amphetamines, among the medical students evaluated. Drug use (except that of marijuana and inhalants) was comparable between the genders, and academic year was an important influencing factor. DISCUSSION: Increased inhalant use was observed among the medical students, especially among males and students in the early undergraduate years. This is suggestive of a specific behavioral pattern among medical students. Our findings corroborate those of previous studies. CONCLUSION: Inhalant use is on the rise among medical students at the Universidade de São Paulo School of Medicine. Because of the negative health effects of illicit drug use, further studies are needed in order to deepen the understanding of this phenomenon and to facilitate the development of preventive measures.

Rapid fluidic exchange microsystem for recording of fast ion channel kinetics in Xenopus oocytes.

We present a new lab-on-a-chip system for electrophysiological measurements on Xenopus oocytes. Xenopus oocytes are widely used host cells in the field of pharmacological studies and drug development. We developed a novel non-invasive technique using immobilized non-devitellinized cells that replaces the traditional "two-electrode voltage-clamp" (TEVC) method. In particular, rapid fluidic exchange was implemented on-chip to allow recording of fast kinetic events of exogenous ion channels expressed in the cell membrane. Reducing fluidic exchange times of extracellular reagent solutions is a great challenge with these large millimetre-sized cells. Fluidic switching is obtained by shifting the laminar flow interface in a perfusion channel under the cell by means of integrated poly-dimethylsiloxane (PDMS) microvalves. Reagent solution exchange times down to 20 ms have been achieved. An on-chip purging system allows to perform complex pharmacological protocols, making the system suitable for screening of ion channel ligand libraries. The performance of the integrated rapid fluidic exchange system was demonstrated by investigating the self-inhibition of human epithelial sodium channels (ENaC). Our results show that the response time of this ion channel to a specific reactant is about an order of magnitude faster than could be estimated with the traditional TEVC technique.

Academic advising, eh : a profile of undergraduate academic advising at Ontario universities

Despite its importance to postsecondary students' success, there is little known about academic advisement in Canada. Academic advising can be a very intensive and demanding job, yet it is not well understood what duties or student populations of advising make it so. On a practical level, this study sought to learn more about academic advisement in Ontario universities and provide a general overview of who advisors are and what they do. This study also investigated academic advising duties and time allocation for these responsibilities in an attempt to relate theory to practice incorporating Vilfredo Pareto's theoretical underpinnings to confirm or negate the applicability of the Pareto Principle in relationship to time utilization by advisors. Essentially this study sought to discover which students require the greatest advisement time and effort, and how advisors could apply these findings to their work. Academic advising professionals in Ontario universities were asked to complete a researcher-designed electronic survey. Quantitative data from the responses were analyzed to describe generalized features of academic advising at Ontario universities. Discussion and implications for practice will prompt advisors and institutions using the results of this study to measure themselves against a provincial assessment. Advisors' awareness of time allocation to different student groups can help focus attention where new strategies are needed to maximize time and efforts. This study found that caseload and time spent with student populations were proportional. Regular undergraduate students accounted for the greatest amount of caseload and time followed by working with students struggling academically. This study highlights the need for further evaluation, education, and research in academic advising in Canadian higher education.

Exploring Academic (Di)stress and Help-Seeking in Faculty of Education Students

This is a study of education students’ conceptions of and experiences with academic stress and help-seeking. The study explored teacher education and Master of Education students’ academic stress by examining causes of academic stress and how these stressors affect students’ academic and university experiences. Stress-related help-seeking was also a focus of this study, and was explored using inquiries regarding where participants sought stress-related support. Additionally, exploring students’ use of the Internet for stress-related information or support was a goal of this study. These research goals were pursued using a qualitative methodology that applied grounded theory design. Consequently, data were used to develop a theory that would contribute to existing literature. Specifically, participant descriptions related to causes of and responses to academic stress aligned with Maslow’s (1954) theory of human motivation and Alderfer’s (1969) E. R. G. theory, and led to theoretical contributions that took a hierarchy of student needs and motivation into consideration.

Academic and social adjustment of teenagers in social rehabilitation : the role of intrinsic need satisfaction and autonomy support

Les études antérieures ont démontré les bénéfices de la satisfaction des besoins intrinsèques et du soutien à l’autonomie dans le domaine de l’éducation. Or, l’applicabilité des tenants principaux de la Théorie de l’Auto-Détermination (TAD; Deci & Ryan, 2000) n’a pas été investiguée auprès d’une population clinique d’adolescents. L’objectif de cette thèse doctorale est de faire la lumière sur la façon dont l'adaptation scolaire et sociale peut être favorisée par les agents de socialisation dans le contexte de la réadaptation sociale. Cette thèse est composée de deux études s’intéressant à l’application des tenants clés de la TAD auprès de deux échantillons d’adolescents vivant des problèmes d’adaptation et recevant des services d’éducation spécialisée et de réadaptation sociale. Les relations entre les concepts motivationnels de base sont étudiés afin de déterminer si, comme la TAD le propose, la satisfaction des besoins intrinsèques des jeunes peut être soutenue par le style interpersonnel des agents de socialisation (c.-à-d., le soutien à l’autonomie, l’implication et la structure). Il est aussi vérifié si ces concepts motivationnels améliorent la motivation ainsi que d’autres conséquences qui résultent de leur expérience, proposées par la TAD. La première étude a évalué si le style interpersonnel des enseignants peut favoriser la satisfaction des besoins des élèves, leur style de motivationl, tout comme leur ajustement scolaire. Les élèves en difficulté d’adaptation (N = 115) inscrits aux écoles internes des Centres de Réadaptation en raison de leurs problématiques émotionnelles et comportementales ont rempli les questionnaires à deux reprises, au début et à la fin de l’année scolaire. Les analyses de modèles d’équations structurelles révèlent que l’augmentation du soutien à l’autonomie et de l’implication (mais pas de la structure) des enseignants pendant l’année est associée à une augmentation de la satisfaction des besoins des élèves qui, conséquemment, conduit à une motivation scolaire plus auto-déterminée et à une diminution d’intentions de décrochage à la fin de l’année scolaire. De plus, l’amélioration de la satisfaction des besoins mène directement à une meilleure expérience affective à l’école. La deuxième étude consiste en une recherche expérimentale conduite auprès d’adolescentes en difficulté d’adaptation (N = 29). Le devis expérimental a permis de comparer l’impact de la présence (c. absence) du soutien à l’autonomie sur l’internalisation d’une tâche et sur les conséquences motivationnelles et expérientielles des jeunes. La tâche, fastidieuse mais importante, consistait à de la résolution de problèmes interpersonnels (activité clinique). Les résultats suggèrent qu’un style interpersonnel soutenant l’autonomie a augmenté la motivation auto-déterminée, la perception de la valeur de la tâche et son appréciation, ainsi que diminué les affects négatifs comparativement à la condition sans soutien à l’autonomie. Les résultats sont discutés en lien avec les implications théoriques et pratiques d’étendre la portée de la TAD à une population clinique d’adolescents aux prises avec des difficultés d’adaptation.

Geochemical, Sedimentological And Remote Sensing Studies Of Kayamkulam Estuary, South West Coast Of India- A Gis Approach

In this study, an attempt has been made to find the textural, geochemical, sedimentological characteristics of sediments and water phases of the kayamkulam estuary located in the Southwest coast of Kerala, besides the impact of gas based thermal power plant located at the northern part of the estuary. Estuaries are an important stage in the transport of the solid weathering product of the earth’s crust. These weathered products or sediments are complex mixtures of a number of solid phases that may include clays, silica, organic matter, metal oxides, carbonates, sulfides and a number of minerals. Studies on the aquatic systems revealed the fact that it posses severe ecological impairments due to heavy discharge of sediments from 44 rivers, the continued disposal of pollutants rich materials from industries, sewage channels, agricultural areas and retting yards

La influencia del autoconcepto en el rendimiento académico en estudiantes universitarios. 'The influence of self-concept on academic achievement in university students'.

Resumen tomado de la publicación. Con el apoyo económico del departamento MIDE de la UNED. Incluye anexo con el cuestionario utilizado para la realización del estudio

The Ethics of Ethics Reviews in Global Health Research: Case Studies Applying a New Paradigm

With increasing calls for global health research there is growing concern regarding the ethical challenges encountered by researchers from high-income countries (HICs) working in low or middle-income countries (LMICs). There is a dearth of literature on how to address these challenges in practice. In this article, we conduct a critical analysis of three case studies of research conducted in LMICs.We apply emerging ethical guidelines and principles specific to global health research and offer practical strategies that researchers ought to consider. We present case studies in which Canadian health professional students conducted a health promotion project in a community in Honduras; a research capacity-building program in South Africa, in which Canadian students also worked alongside LMIC partners; and a community-university partnered research capacity-building program in which Ecuadorean graduate students, some working alongside Canadian students, conducted community-based health research projects in Ecuadorean communities.We examine each case, identifying ethical issues that emerged and how new ethical paradigms being promoted could be concretely applied.We conclude that research ethics boards should focus not only on protecting individual integrity and human dignity in health studies but also on beneficence and non-maleficence at the community level, explicitly considering social justice issues and local capacity-building imperatives.We conclude that researchers from HICs interested in global health research must work with LMIC partners to implement collaborative processes for assuring ethical research that respects local knowledge, cultural factors, the social determination of health, community participation and partnership, and making social accountability a paramount concern.

Review of recent research (1998-2012) in German for Academic Purposes (GAP) in comparison with English for Academic Purposes (EAP): cross-influences, synergies and implications for further research

This state-of-the-art review reports on the major studies conducted in the field of Deutsch als Wissenschaftssprache (academic German) since the late 1990s. To begin with, the current position of German as a language of academic communication nationally and internationally will be discussed, focusing especially on the challenges posed by the status of English as a lingua franca. Subsequently, the major research undertaken since the late 1990s will be reviewed and its contribution to the development of teaching materials evaluated. Since studies on academic German have been influenced, to some extent, by research in English for Academic Purposes (EAP), this paper also attempts to dovetail developments in EAP in order to highlight commonalties and differences. The final sections will discuss some potential synergies and implications for further research in both fields.

Where have all the linguists gone? The position of Linguistics in British German Studies from the mid-19th century until 2000

Retrospectively, Linguistics - understood as a scientific study of language - has been an important part of British German Studies. In fact, the establishment of modern language as academic disciplines in the UK is closely related to the Germanic philology and the interest in the history, and structure of languages. However, over the last few decades, a demise of Linguistics in the departments of modern languages has been observed. The aim of this paper is to survey the position of linguistic research and teaching in the discipline of German Studies in the UK. To begin with, I will give a brief account of the history of linguistic/ language studies in the discipline. Subsequently, the current position of Linguistics in research and teaching will be scrutinised. Finally, this paper will discuss the importance of linguistic insights for the discipline of German Studies, with particular reference to teaching.

The value of ISE : main studies and investor perspective

This study has been prepared with the aim of bringing together the main research lines that seek to identify and convey the value of participating in initiatives like the ISE. This document is structured on three major fronts. On the first front, we conducted a survey to collect the main data on SRI trends in the two largest market niches: Europe and the United States, besides results from an MIT research study conducted among executives on the value of sustainability in the current market. Next, we carried out a non-exhaustive survey on academic studies that seek to identify the intangible and tangible gains achieved by companies through their participation in the ISE or related initiatives. Finally, we present the results of a survey done with major Brazilian pension funds aimed at investigating the knowledge of the ISE and how it could be used in their analysis and decision-making process.

Correlation between structural data and spectroscopic studies of a new beta-diketonate complex with trivalent europium and gadolinium

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)