948 resultados para observation sentence
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We present a site-resolved study of stow (ms to s) motions in a protein in the solid (microcrystalline) state performed with the use of a modified version of the centerband-only detection of exchange (CODEX) NMR experiment. CODEX was originally based on measuring changes in molecular orientation by means of the chemical shift anisotropy (CSA) tensor, and in our modification, angular reorientations of internuclear vectors are observed. The experiment was applied to the study of stow (15)N-(1)H motions of the SH3 domain of chicken a-spectrin. The protein was perdeuterated with partial back-exchange of protons at labile sites. This allowed indirect (proton) detection of (15)N nuclei and thus a significant enhancement of sensitivity. The diluted proton system also made negligible proton-driven spin diffusion between (15)N nuclei, which interferes with the molecular exchange (motion) and hampers the acquisition of dynamic parameters. The experiment has shown that approximately half of the peaks in the 2D (15)N-(1)H correlation spectrum exhibit exchange in a different extent. The correlation time of the slow motion for most peaks is 1 to 3 s. This is the first NMR study of the internal dynamics of proteins in the solid state on the millisecond to second time scale with site-specific spectral resolution that provides both time-scale and geometry information about molecular motions.
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The optical, magnetic and structural properties of Eu doped low silica calcium aluminosilicate glasses were investigated. The optical absorption coefficient presented two bands at 39 246 and 29 416 cm(-1), which were assigned respectively to the 4f(7) ((8)S(7/2)) -> 4f(6) (4F(J)) 5d (T(2g)), and 4f(7) ((8)S(7/2)) -> 4f(6) (4F(J)) 5d (E(g)) transitions of Eu(2+). The fluorescence measured at 300 K on a sample doped with 0.5 wt% of Eu(2)O(3) exhibited a broad band centered at 17 350 cm(-1), which is attributed to the 4f(6)5d -> 4f(7) transition of Eu(2+), whereas the additional peaks are due to the (5)D(0) -> (7)F(J) (J = 1, 2, 4) transitions of Eu(3+). From magnetization and XANES data it was possible to evaluate the fractions of Eu(2+) and Eu(3+) for the sample doped with 0.5 and 5.0 wt% of Eu(2)O(3), the values of which were approximately 30 and 70%, respectively.
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This paper proposes a novel way to combine different observation models in a particle filter framework. This, so called, auto-adjustable observation model, enhance the particle filter accuracy when the tracked objects overlap without infringing a great runtime penalty to the whole tracking system. The approach has been tested under two important real world situations related to animal behavior: mice and larvae tracking. The proposal was compared to some state-of-art approaches and the results show, under the datasets tested, that a good trade-off between accuracy and runtime can be achieved using an auto-adjustable observation model. (C) 2009 Elsevier B.V. All rights reserved.
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A high-energy intermediate in the peroxyoxalate reaction can be accumulated at room temperature under specific reaction conditions and in the absence of any reducing agent in up to micromolar concentrations. Bimolecular interaction of this intermediate, accumulated in the reaction of oxalyl chloride with hydrogen peroxide, with an activator (highly fluorescent aromatic hydrocarbons with low oxidation potential) added in delay shows unequivocally that this intermediate is responsible for chemiexcitation of the activator. Activation parameters for the unimolccular decomposition of this intermediate (Delta H(double dagger) = 11.2 kcal mol(-1); Delta S(double dagger) = -23.2 cal mol(-1) K(-1)) and for its bimolecular reaction with 9,10-diphenylanthracene (Delta H(double dagger) = 4.2 kcal mol(-1); Delta S(double dagger) = -26.9 cal mol(-1) K(-1)) show that this intermediate is much less stable than typical 1,2-dioxetanes and 1,2-dioxetanones and demonstrate its highly favored interaction with the activator. Therefore, it can be inferred that structural characterization of the high-energy intermediate in the presence of an activator must be highly improbable. The observed linear free-energy correlation between the catalytic rate constants and the oxidation potentials of several activators definitely confirms the occurrence of the chemically initiated electron-exchange luminescence (CIEEL) mechanism in the chemiexcitation step of the peroxyoxalate system.
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The aim with this study is to explore if and how linguistic learning takes places when four pairs ofstudents in grade one writes on the computer. Observations of eight students took place duringtwelve lessons to investigate what happened during their writing processes. This study isimportant because students’ computer writing is a relatively new phenomenon in the Swedishprimary school.It is clear that the peer collaboration creates a complex interaction that becomes the platform, andalso the prerequisite, for successful language training. The method can clearly give students profitsin their linguistic development. When working in pairs, children support each other in writing andreading. They also get to train letter knowledge, phonemic awareness and the correspondencebetween phonemes and graphemes. Although the method creates good possibilities for readingand writing development, it cannot be the only way to learn reading. There are also risks thatstudents get stuck in different positions that can affect their progresses, which is important thatthe teachers consider while creating writing pairs. Teachers need to identify student’s reading andwriting development processes and also be able to create reading and writing instruction thatprovides different learning strategies.
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There is a lack of research on the everyday lives of older people in developing countries. This exploratory study used structured observation and content analysis to examine the presence of older people in public fora, and considered the methods’ potential for understanding older people’s social integration and inclusion. Structured observation occurred of public social spaces in six cities each located in a different developing country, and in one city in the United Kingdom, together with content analysis of the presence of people in newspaper pictures and on television in the selected countries. Results indicated that across all fieldwork sites and data sources, there was a low presence of older people, with women considerably less present than men in developing countries. There was variation across fieldwork sites in older people’s presence by place and time of day, and in their accompanied status. The presence of older people in images drawn from newspapers was associated with the news/non-news nature of the source. The utility of the study’s methodological approach is considered, as is the degree to which the presence of older people in public fora might relate to social integration and inclusion in different cultural contexts.
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The Arctic is affected by global environmental change and also by diverse interests from many economic sectors and industries. Over the last decade, various actors have attempted to explore the options for setting up integrated and comprehensive trans-boundary systems for monitoring and observing these impacts. These Arctic Observation Systems (AOS) contribute to the planning, implementation, monitoring and evaluation of environmental change and responsible social and economic development in the Arctic. The aim of this article is to identify the two-way relationship between AOS and tourism. On the one hand, tourism activities account for diverse changes across a broad spectrum of impact fields. On the other hand, due to its multiple and diverse agents and far-reaching activities, tourism is also well-positioned to collect observational data and participate as an actor in monitoring activities. To accomplish our goals, we provide an inventory of tourism-embedded issues and concerns of interest to AOS from a range of destinations in the circumpolar Arctic region, including Alaska, Arctic Canada, Iceland, Svalbard, the mainland European Arctic and Russia. The article also draws comparisons with the situation in Antarctica. On the basis of a collective analysis provided by members of the International Polar Tourism Research Network from across the polar regions, we conclude that the potential role for tourism in the development and implementation of AOS is significant and has been overlooked.
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You cannot teach architectonic design, but only learn it. This sentence was, during some decades, especially during the modernism, the starting point, adopted by several architectonic design professors, when they had to approach their subject. An attitude that, some years ago, was reviewed and fighted by area s experts. This paper join this criticism, and try to add something to the pre-existing discussion, analyzing with the case-study method all the subjects related with architectonic design of the Architecture and Urbanism degree, at Universidade Federal do Rio Grande do Norte CAU/UFRN . The aim is to identify and analyze the teaching methodologies used by the professors and their effects related to the students. To reach this purpose four different methods were used: i) Professors interviews; ii) Different forms submitted to students and professors; iii) Daily practice s observation, developed during classes; iv) Documents analysis about the degree (historical development and subjects) and about the subjects themselves (summaries, table of contents and planning). Studying the results, it was possible to underline that, in spite of the efforts of some of the professors to find a way to teach with more appropriate educational and pedagogic bases, some of the teaching methodologies, criticized in articles dealing with the matter, were still used. With regard to these, the research pointed out some suggestions that could help to improve the teaching and learning process, joining professors and students that are the most important subjects of the teaching activity. Developing the idea living in the paper s title Teaching and learning , it s now clear that only the practice, through the improvement of the pedagogic techniques, together with critical analysis can help the professors to reach a relationship level, regarding the teaching and learning process, as that described in the epigraph s text, into which teaching and learning, can t be done only by one of the process subject, but must be lived by both of them: professors and students
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In the present work, the anodic oxide films of Al, Al-Cu 4.5% and Al-Si 6.5% alloys are formed using direct and pulse current. In the case of Al-Cu and Al-Si alloys, the electrolyte used contains sulfuric acid and oxalic acid, meanwhile for Al the electrolyte contains sulfuric acid only. Al-Cu alloy was submitted to a heat treatment in order to decrease the effect of inter metallic phase theta upon the anodic film structure. Fractured samples were observed using a field emission gun scanning electron microscope JSM-6330F at (LME)/Brazilian Synchrotron Light Laboratory (LNLS), Campinas, SP, Brazil. The oxide film images enable evaluation of the pore size and form with a resolution similar to the transmission electron microscope (TEM) resolution. It is also observed that the anodizing process using pulse current produces an irregular structure of pore walls, and by direct cur-rent it is produced a rectilinear pore wall. (c) 2005 Elsevier B.V. All rights reserved.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This work has its genesis in the life of a teacher. It contemplates the report of a great story that expresses the political will of anonymous people who sought/seek to overcome challenges and prejudices, a joint effort to make real the right to literacy. The reported story was developed in the Pedagogic Clinic Teacher Heitor Carrilho, Natal-RN which, concerned about the sentence of 'unable to learn the written language' attributed to children and young public school students, decided to invest in overcoming prejudices and fight against school failure of these underprivileged. The problem that motivated the study was thus set up: What particularities characterize a pedagogical practice which aims to teach literacy to children and youth from public schools, considered not capable of learning the written language? What theoretical and methodological procedures are shown as a boost to literacy in the development of a pedagogical practice systematically targeted to reflect the perspective of educating those students in public schools? Aiming to answer these questions, we conducted a qualitative research having as methodology, Life Stories and Research/Formation. For the construction of the data, it was decided to use the participative observation, semi-structured interviews and document analysis. Guided by the principles of content analysis the data analysis was built, from which emerged two categories: theoretical and methodological procedures aligned to the major axes of literacy and Procedures of the specific theoretical and methodological fundamentals of literacy. As subsets of the transverse procedures others were seized: didactic-pedagogic procedures; social affective procedures. Regarding these ones, the research shows the importance of the teacher to build a relationship of listening to the students and their families in order to organize the pedagogical work, looking at multiple dimensions of the subject: the intellect, the creative, the affective, moral, noting that between the methodology and didactics or as part of it, the links built represent great opportunities to promote literacy. Regarding the specific procedures, others were built: procedures that emphasize oral communication, procedures that favor writing and procedures that privilege reading. Under these procedures, the results of research show that you can only promote literacy if the teacher provides the students effective conditions of understanding the principles of alphabetical notation from the use of various kinds of texts, leading them to comprehend and use them in different contexts. Therefore, instructors must meet the learners' prior knowledge, their language, and the learning real needs that will bring new challenges consistent with their possibilities. The research confirms the importance of the Educational Support extra school. However, it is essential to emphasize that it is a function of the school to promote literacy for all students in the early years of schooling. It is recorded, however, that for the implementation of this desire, we must break the school model characterized by a rigid tradition, in which there is only room for those who learn the content taught in a minimum time. Unfortunately, despite the discourse of inclusion and ensuring the right to education, the school remains exclusive and selective separating the school learning of interpersonal relations and social integration and performance. On the one hand, research showed the difficulties of conducting studies and/or strategies that address the particularities of children and young people believed not capable of learning. On the other hand, the political commitment and motivation have increased the perception that it is possible to mitigate the existing deficits in the educational context, beginning with the everyday teaching practice, in which new knowledge can be learned, methodologies can be improved and, despite everything, the educational success can be built