Measurement of the epicycle frequency in the Galactic disc and initial velocities of open clusters

A new method to measure the epicycle frequency kappa in the Galactic disc is presented. We make use of the large data base on open clusters completed by our group to derive the observed velocity vector (amplitude and direction) of the clusters in the Galactic plane. In the epicycle approximation, this velocity is equal to the circular velocity given by the rotation curve, plus a residual or perturbation velocity, of which the direction rotates as a function of time with the frequency kappa. Due to the non-random direction of the perturbation velocity at the birth time of the clusters, a plot of the present-day direction angle of this velocity as a function of the age of the clusters reveals systematic trends from which the epicycle frequency can be obtained. Our analysis considers that the Galactic potential is mainly axis-symmetric, or in other words, that the effect of the spiral arms on the Galactic orbits is small; in this sense, our results do not depend on any specific model of the spiral structure. The values of kappa that we obtain provide constraints on the rotation velocity of the in particular, V(0) is found to be 230 +/- 15 km s(-1) even if the scale (R(0) = 7.5 kpc) of the Galaxy is adopted. The measured kappa at the solar radius is 43 +/- 5 km s(-1) kpc(-1). The distribution of initial velocities of open clusters is discussed.

Multilevel Training of Binary Morphological Operators

The design of binary morphological operators that are translation-invariant and locally defined by a finite neighborhood window corresponds to the problem of designing Boolean functions. As in any supervised classification problem, morphological operators designed from a training sample also suffer from overfitting. Large neighborhood tends to lead to performance degradation of the designed operator. This work proposes a multilevel design approach to deal with the issue of designing large neighborhood-based operators. The main idea is inspired by stacked generalization (a multilevel classifier design approach) and consists of, at each training level, combining the outcomes of the previous level operators. The final operator is a multilevel operator that ultimately depends on a larger neighborhood than of the individual operators that have been combined. Experimental results show that two-level operators obtained by combining operators designed on subwindows of a large window consistently outperform the single-level operators designed on the full window. They also show that iterating two-level operators is an effective multilevel approach to obtain better results.

Brachiaria decumbens supresses the initial growth of Coffea arabica

Brachiaria decumbens vem se tornando uma das plantas daninhas mais freqüentes na infestação de cafezais em formação, pois além de sua elevada agressividade e dificuldade de controle, está ocorrendo expansão das áreas cafeeiras para locais anteriormente ocupados por pastagens. Objetivou-se neste trabalho avaliar os efeitos desta planta daninha, em densidades crescentes, sobre o desenvolvimento inicial de mudas de café (Coffea arabica L. cv. Catuaí Amarelo). O experimento foi conduzido em condições semi-controladas, sem limitação de água. Uma muda de café foi transplantada em caixa de amianto com capacidade para 70 L, preenchida com terra coletada da camada arável de um Latossolo Vermelho. Os tratamentos constaram de diferentes densidades de transplante de capim-braquiária, a saber: 0, 4, 8, 12, 16, 20, 24, 36, 48 e 60 plantas m-2. O ensaio foi conduzido por um período experimental de 120 dias após o plantio (DAP). Todas as características analisadas foram afetadas negativamente pela interferência da planta daninha, mas as que se mostraram mais sensíveis a essa interferência foram à área foliar e a biomassa seca das folhas. Houve redução de 41,8% na área foliar do cafeeiro quando conviveu com o capim-braquiária a partir da densidade de 8 plantas m-2, chegando a 68,7% na densidade de 60 plantas m-2. Também a partir da densidade de 8 plantas m-2, a redução na biomassa seca das folhas em relação à testemunha foi de 41,4% e na densidade de 60 plantas m-2 chegou a 72,8%. Brachiaria decumbens, a partir da densidade de 8 plantas m-2, interfere negativamente sobre as mudas de café até os 120 DAP.

Weed control strip influences the initial growth of Eucalyptus grandis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Os ateliês (auto)formativos na constituição do sujeito docente da educação matemática

The object of study of this thesis is the use of (self)training workshops as a fundamental process for the constitution of the teaching subject in mathematics education. The central purposes of the study were to describe and analyze a learning process of mathematics teachers supported by the training-research methodology, which procedures have been affected with the practice of (self)training workshops as a way of collaborating to the constitution of the teaching subject in Mathematics Education. The survey was conducted with a group of teachers in the city of Nova Cruz, Rio Grande do Norte through a process of continued education realized in the training workshops having as main goal the realization of the group s (self)training sessions in order to lead participants to the extent of their autonomy in their personal and professional transformations. The results obtained in the formative processes have shown the need to develop activities of mathematics teaching as a contribution to overcome the conceptual difficulties of the teachers, apart from their (self)reflections about themselves and the educational processes in which they belong. The results raised some propositions about (self)training workshops that may be incurred in practices to be included in the curriculum frameworks or materialize as a strategy of pedagogical work in training courses for teachers of mathematics. Also, they can constitute an administrative and educational activity to be instituted in the public schools of Basic Education

Trabalho e formação docente na rede municipal de ensino de natal

The study Teacher work and education in the municipal schools of Natal objectifies the analysis of the education and work conditions of the teachers in the municipal schools of Natal, placing them within the scenario of the public policies outlined for Basic Education (2005-2010). The thesis is based on the perspective that the educational reforms implemented by the Brazilian government in an attempt to answer to the new contextual demands originated from the world of work and globalization, demanding increasingly higher levels of qualification and constant extension of the teaching functions in school from the teachers, have been configured withal as a strategy for intensifying the teacher s work. The empirical field of study was constituded by thirteen municipal schools that offer basic education. Four hundred and seventeen teacher subjects that work in the municipal school system of Natal, two representatives of the Secretaria Municipal de Educação de Natal (SME)1 that work in the pedagogical team and one representative of the Sindicato dos Trabalhadores em Educação do Rio Grande do Norte2 took part in the study. The procedures/instruments used in the research were: bibliographic review, document research, questionnaires and recording of information in a field journal. The study confirmed that the majority of the teachers that work in the municipal school system were admitted by means of public entry exams, therefore meeting the requirements set by Law 9.394/96. Most of the teachers have the initial education demanded to work in basic education, although with some limitations due to the fact that they do not correspond to the needs of the educational system. The SME has a plan for continued training of the teachers in accordance to the current ideas defended by researchers of this field. There is, although, a disconnection between the purpose of the plan and the training strategies, because, in truth, predominate repetitive and specific actions that do not contemplate the training needs of the teachers, nor the demands of the system. Although the work conditions are evaluated, by the teachers, as relatively good, limits in relation to the physical structure of the schools are observed (dirty walls with holes in them, broken ceiling fans, old chairs and desks, old and stained black boards, inadequate restroom installations, poor maintenance of the computers, amongst other items). It was also verified the an increase in the functions of the teachers and an intensification of their work, materialized through an overburden of activities undertaken daily at school (and outside of it) and through the demand in taking part in activities that go beyond those inherent to the teaching process, such as the elaboration of political-pedagogical projects, participation in collegiate, registration of student information solicited by the SME and the participation in commissions, has been happening

Formando-se professor(a) da educação infantil: a escola com contexto

This work is the result of a set of experiences and reflections on teaching in kindergarten and, in particular, the issues raised by first experiences as a teacher and how these issues were being gradually answered from the experience in a school . Guided by these experiences and studies of Oliveira-Formosinho (2002) on the training of kindergarten teachers in the school context, among others as: Barreto, Kuhlmann Jr. (1998), Vasconcelos et. al. (2000); Nóvoa (1992, 1995), Moita (1995), Freire (1996), Tardif (2002, 2009) Kramer (2005) and Hargreaves, Fullan (2000), built as study questions: what situations become in the context of professional training at an institution of early childhood education? Which subjects who took part? How involved? From this perspective the goal of our work is a: to investigate, from the perspective of teachers a public kindergarten, situations of professional interaction that become the context of teacher education. The research took the principles of qualitative approach and an intrinsic case study (STAKE, 1998), whose locus was a Municipal Center for Early Childhood Education, so defined by their peculiarities for training faculty in the context of practice. We built the data with a group of nine teachers CMEI this by conducting a questionnaire, interviews and document analysis. Data analysis, guided by the principles of content analysis, allowed to note that beyond the initial training and personnel, the school context contributes to its fundamental training for teachers of kindergarten, whereas their specificities. We conclude by confirming that systematic and unsystematic in situations developed in the school routine, interaction with peers and other members of the school, the teachers take ownership of specific knowledge specific to teaching in kindergarten

O ambiente virtual na formação inicial de professores de alemão como apoio para o ensino e a aprendizagem da língua e a reflexão sobre ações docentes

Estudiosos dos campos da Educação, da Linguística Aplicada e da Formação de Professores de Línguas insistem hoje na grande importância da inclusão de Tecnologias de Informação e Comunicação (TICs) na formação inicial, bem como na necessidade de promover o desenvolvimento do pensamento crítico-reflexivo dos futuros professores. Tomando como pressupostos teóricos estudos acerca das características da sociedade de informação, dos ambientes virtuais e da formação de professores, este trabalho tem como objetivo discutir possibilidades oferecidas pela plataforma Moodle de aprendizagem na formação inicial de professores de alemão. Para tanto, apresentaremos diferentes formas de uso de ambientes virtuais e de ferramentas neles disponíveis, que demonstraram ser de grande valor no processo de formação de licenciandos, tanto em língua alemã, quanto durante suas práticas iniciais. As experiências apontam para um valor inestimável de ambientes virtuais no acompanhamento de licenciandos no processo de aprendizagem da língua e nas primeiras experiências com a docência.

A estratégia didática de resolução de problemas na formação de professores de química

In this work it is presented a research developed in the initial training of teachers of the chemistry graduation course at the Universidade Federal do Rio Grande do Norte (UFRN). The intervention was realized in two classes in the context of a discipline in the curricular structure with nineteen undergraduate students of chemistry. The study utilizes characteristics of the qualitative approach and uses observation, questionnaires, interviews and examination papers. The experiment involved a sequence of activities fundamented on the Problem Solving (PS) teaching strategy to approach chemical concepts. The proposal was planned and organized according to the theoretical presupposition of the work developed by the authors of the Science Education in PS, of teaching experience and from the initial hypotheses of the research. The goal was that the future teachers could experience the strategy and advance to the new meanings. The themes addressed in the activities were the difference between exercises and problems, exercises turning into problems, the steps of problem solving and some implications of the teaching strategy for the work of the teacher. The results showed evidence that through a process of collective reflection, and from the difficulties experienced in the strategy practice, the undergraduates are introduced to new perspectives of reflection and action of teaching practice, and understanding some benefits of innovative proposals for the teaching of chemistry. It also showed that, although this theme is approached, in some moments of the graduation, the future teachers don‟t know when or how to realize activities in this perspective. From the aspects that rose in research we highlighted the difficulties in the problem solving steps, the use of the strategy in school and the knowledge and skills of the teacher for planning activities in Problem Solving

Refinement and initial validation of a multidimensional composite scale for use in assessing acute postoperative pain in cats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Celecoxib treatment does not alter recruitment and activation of osteoclasts in the initial phase of experimental tooth movement

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Knowledge of firefighters with special paramedic training of the emergency management of avulsed teeth

Immediate replantation into the socket is the ideal procedure in cases of accidental avulsion of permanent teeth. In Brazil, firefighters with special paramedic training are in charge of providing first-aid care to victims of road accidents and might have to deal with tooth avulsions. This study assessed the knowledge of firefighters regarding the emergency management of avulsed teeth. Information was collected from a questionnaire submitted to 110 volunteer firefighters in seven cities in the São Paulo State (Brazil). The results revealed that 70.9% of the respondents did not know what tooth avulsion was; 53.6% did not know what tooth replantation was or defined it incorrectly; 60% would not act properly in tooth avulsion cases; 20.9% did not consider replantation of the avulsed tooth into the socket as a treatment option; the ideal time interval for tooth replantation was unknown to 40% of the interviewees; 90% of the participants answered that they would not be able to perform tooth replantation. Among those who considered themselves unable to perform tooth replantation, 47.3% chose saline as the best storage medium for an avulsed tooth, 21.8% chose milk, 3.6% chose the patient's mouth and 20% reported not knowing where to store the tooth; 81.8% of the firefighters reported not to have ever received any specific directions on tooth replantation and 100% of them considered this knowledge a requirement for first-aid care to accident victims. In conclusion, the knowledge of the surveyed firefighters regarding emergency management after tooth avulsion was unsatisfactory in several aspects that are important for the success of replantation procedures. Firefighters with special paramedic training should be educated on how to proceed in cases of dentoalveolar traumas and tooth avulsions in order to improve treatment prognosis and increase the survival rate of replanted teeth.

Evaluation of Laser Fluorescence in the Monitoring of the Initial Stage of the De-/Remineralization Process: An in vitro and in situ Study

This study aimed to evaluate laser fluorescence (LF) for monitoring the initial stage of subsurface de- and remineralization (<150 mu m depth). Ninety-six sound blocks of bovine enamel, selected according to surface hardness (SH) and LF were used in two experimental studies, in vitro and in situ. In vitro, blocks were exposed to a demineralizing solution, then remineralized by pH cycling for 6 days. In situ, 10 volunteers wore acrylic palatal appliances, each containing 4 dental enamel blocks that were demineralized for 14 days by exposure to 20% sucrose solution. Following this treatment, blocks were submitted to remineralization for 1 week with fluoride dentifrice (1,100 mu g F/g). In both experiments, SH and LH were measured after demineralization and after remineralization. Further, enamel blocks were selected after the demineralization/remineralization steps for measurement of cross-sectional hardness and integrated loss of subsurface hardness (Delta KHN). SH and Delta KHN showed significant differences among the phases in each study. LF values for sound, demineralized and remineralized enamel were: 5.2 +/- 1.1, 8.1 +/- 1.2 and 5.6 +/- 0.8, respectively, in the in vitro study, and 5.3 +/- 0.3, 16.5 +/- 4.7 and 6.5 +/- 2.5, respectively, in the in situ study, values for demineralized enamel being significantly higher than for sound and remineralized enamel in both studies. However, LF was correlated with Delta KHN only in situ. LF was capable of monitoring de- and remineralization in early lesions in situ, when bacteria are presumably present in the caries lesion body, but is not correlated with mineral changes in bacteria-free systems. Copyright (C) 2009 S. Karger AG, Basel

Influence of light quality on germination and initial growth of canephori seedlings Peltophorum dubium (Sprenge) Taub.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)