23 resultados para ALAS SUPERLATTICES
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Massive resection of the small intestine results in short bowel syndrome with anti-absorptive effect and repercussions on the metabolism. Morphologic and functional evaluation may be necessary in order to control wrapped organs. Scintigraphy an examination with little invading and no biologic damage can be used. The purpose were to assess the biodistribution of sodium pertecnetate in organs of rats subjected to massive resection of the small intestine, the intestinal adaptation of the remnant intestinal mucosa and weight curve evaluation in the postoperative period. Twenty-one Wistar rats were randomly allocated into three groups (n = 7). The operated group named short bowel (SB) after anesthetized was subjected to massive resection of the small intestine; the control group (C), and sham group (SHAM). On the 30th postoperative day, 0.l mL of sodium pertechnetate was injected into the venous orbital plexus. After 30 minutes, the rats were killed with an overdose of anesthetic, and fragments of the liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, femur and brain were harvested. The percentage of radioactivity per gram of tissue (%ATI/g) was determined using Gama Counter WizardTM 1470, PerkinElmer to all samples. Biopsies of 3 cm remaining jejunum were removed to histological analyses. Analysis of variance (ANOVA) and the Tukey test for multiple comparisons were used, considering p<0.05 as significant. The study had the participation of some departments and laboratories, as Nucleus of Experimental Surgery, Department of Surgery, Laboratory of Radiobiology, Department of Pathology and Service of Nuclear Medicine, certifying the character of a multidisciplinary research. The results were no significant differences in %ATI/g of the sodium pertechnetate in the organs of the groups studied (p>0.05). An increase in the weight of the SB rats was observed after the second postoperative week. The jejunal mucosal thickness of the SB rats was significantly greater than that of C and sham rats (p<0.05. The biodistribution of sodium pertechnetate was not affected by massive intestinal resection in rats. An adaptive response by the intestinal mucosa probably contributed to the reversion of weight loss and the biodistribution of sodium pertechnetate was not affected by the surgery
Resumo:
This study investigated the influence of partial colectomy associated with hepatectomy on the biodistribution of the 99mTc-phytate, on metabolic parameters, as well as labeling and morphology of red blood cells. Wistar rats were distributed into three groups (each with 6), nominated as colectomy, colectomy+hepatectomy and sham. In the 30th postoperative day all rats were injected with 99mTc-phytate 0.1mL i.v. (radioactivity 0.66 MBq). After 15 minutes, liver sample was harvested and weighed. Percentage radioactivity per gram of tissue (%ATI/g) was determined using an automatic gamma-counter. Serum AST, ALT, alkaline phosphatase and red blood cells labeling were determined. The liver %ATI/g and red blood cells labeling were lower in colectomy and colectomy+hepatectomy rats than in sham rats (p <0.05), and no difference was detected comparing the colectomy and colectomy+hepatectomy groups. Red blood cells morphology did not differ among groups. Serum levels of AST, ALT and alkaline fosfatase were significantly higher in colectomy+hepatectomy than in colectomy rats (p<0.001). Hepatectomy associated with colectomy lowered the uptake of radiopharmaceutical in liver and in red blood cells in rats, coinciding with changes in liver enzymatic activity
Resumo:
This dissertation presents and discusses the results of an applied research on the accessibility of residents in a Long Term Care Institution (LTCIs) in the city of Natal- RN. The main objective of this research is to suggest projectual improvements that maximize the accessibility in a LTCIs of Natal-RN, considering the aspects of mobility, safety, comfort and independence of elderly residents. Moreover, one should consider the specific characteristics of the user population, capabilities and limitations of the biological process of aging, which causes damage to the neurological system, musculoskeletal and cardiovascular and progressively affects on visual acuity, balance and locomotion of elderly people. This research has a qualitative approach and divided into four phases: exploratory, bibliographical and documentary research, mapping of the LTCIs of Natal-RN, case study. The phase of the mapping presented an overview of accessibility on LTCIs of Natal-RN. The institution of the case study was defined based on the overall assessment of accessibility and ergonomics criteria, preceded by an application of an Ergonomic Work Analysis to understand the accessibility of the elderly people. Interactional and observational methods were used to collect field data. To this end, an intense process of social construction was conducted, involving the elderly residents, caregivers, health professionals and general servants and LTCIs´ managers. It was found that the NBR 9050 is not comprehensive to solve the diversity of accessibility problems found in LTCIs. All LTCIs investigated were in disconformity to the NBR 9050. In the case study, it was found that the inappropriate design hinders the daily activities of the elderly people and is a source of risk of accidents. The environment, facilities and lack of assistive technologies hinder the autonomy of the elderly people, and this LTCI requires ergonomic intervention to improve the accessibility, autonomy and security of the elderly people
Resumo:
The obtaining of ceramic materials from polymeric precursors is subject of numerous studies due to lower energy costs compared to conventional processing. The aim of this study is to investigate and improve the mechanism for obtaining ceramic matrix composite (CMC) based on SiOC/Al2O3/TiC by pyrolysis of polysiloxane in the presence of an active filler and inert filler in the pyrolysis temperature lower than the usually adopted for this technique, with greater strength. It also investigates the influence of pyrolysis temperature, the content of Alas active filler, the presence of infiltrating agents (Al, glass and polymer) after pyrolysis, temperature and infiltration time on some physical and mechanical properties. Alumina is used as inert filler and Al and Ti as active filler in the pyrolysis. Aluminum, glass and polysiloxane are used as agents infiltrating the post-pyrolysis. The results are analyzed with respect to porosity and bulk density by the Archimedes method, the presence of crystalline phases by X-ray diffraction (XRD) and microstructure by scanning electron microscopy (SEM). The ceramic pyrolyzed between 850 °C 1400 °C contain porosity 15% to 33%, density 2.34 g/cm3 and flexural strength at 4 points from 30 to 42 MPa. The microstructure features are porous, with an array of Al2O3 reinforced by TiC particles and AlTi3. The infiltration post-pyrolysis reveals decrease in porosity and increase density and strength. The composites have potential applications where thermal stability is the main requirement
Resumo:
The purpose of this work is to analyze the use of the indicative mood, instead of the subjunctive prescribed by the normative grammar, in complement clauses introduced by the conjunction que in Brazilian Portuguese. Contexts of use of the subjunctive according to grammatical prescription, and contexts of fluctuation on the use of that verbal mood were analyzed, in an attempt to investigate what interferes on the choice of the mood by the user of the language. This study is based on North-American Functional Linguistics theoretical perspective, oriented to analyzing language in use, in the light of the principles of grammaticalization and markedness. The results obtained support that the contexts that favor the indicative over the subjunctive are those composed by a complement clause functioning as a direct object the unmarked clause of all complement clauses and by a verb on the main sentence that belongs to the semantic field of low certainty, corresponding to the epistemic sub-mode the unmarked category of the deontic sub-mode. The results indicate that pragmatics and semantics factors influence the language user on the choice of the verbal mood. This research also presents comparative data on the use of the indicative mood in place of the subjunctive in Brazilian Portuguese and Canadian French, aiming to providing suggestions on language teaching
Resumo:
This paper aims, starting with the studies of languages in contact and communicative competence, to locate and describe the interlanguage, a linguistic phenomenon observed in the interaction between beach sellers and foreign tourists. We seek to discover whether those interacting use some kind of pidgin, or some code as a lingua franca. We also seek to identify the manner in which the features of communicative competence are presented by analyzing the various competences that composes it - linguistic, sociolinguistic, pragmatic and psycholinguistic. The analysis of speech acts, the maxims and conversational implicatures given in the corpus were important to verify whether those interacting were successful in their attempt at multilingual intercomprehension.
Resumo:
This dissertation aims at investigating the teachers beliefs about the role of the reading ability in English at public state high schools in Natal and identifying the social value of the process of learning English for students of a foreign language. From the understanding of studies on reading, both in the field of Cognitive Psychology, as in Gibson & Levin (1975), as in the area of Psycholinguistics, as in Goodman (1970) and Del Re (2006), We researched the teachers perceptions about the skills and competencies that should permeate their educational practices, through their knowledge about theories of language acquisition as Cognitivism (Piaget, 1961) and Social Interactionism (Vygotsky, 1979) and the official documents (PCNEM, 1999; PCN+, 2002 ) that are the parameters for teaching a foreign language. We took into consideration other factors that influence the choice of the goals and the objectives to be worked out, such as: intensity of teachers workload, number of classes and students per class for each teacher, materials and technologies available, among other factors that will play an important role in the choice of the appropriate methodologies. To conduct a case study, two questionnaires were used in the construction of direct interviews with fourteen English teachers in twenty schools. According to data on the teachers beliefs we could find that for them the reading ability does not seem to have an special treatment in the teaching of a foreign language due to factors that undermine this process and therefore make teachers do not realize the real objectives of teaching English at public state high schools in Natal. As a consequence, the current process of education complicates the formation of autonomous learners capable of fighting for a social transformation
Resumo:
This study focuses on the teaching and learning of English based on a new theoretical perspective concerning the Zone of Proximal Development (ZPD), which points to the apprehension of metacognitive processes as the way to reach learning autonomy. The theoretical set underline this study is those of a new pedagogy based on the symbiosis of Bruner‟s (2002) and Freire‟s (2009) concepts and in the metacognitive theory. In a social context dominated by the Communication and Information Technologies (CIT), the integration between teacher and learners with the support of the internet has been used as the way to operationalize this new emergent proposal of the theoretical perspectives. The analyses have been conducted through Systemic and Integral Action Research. The results at the end of this study corroborate our hypothesis that the enlargement of spontaneous knowledge of the learners can facilitate the understanding of scientific concepts, stimulating their metacognition and thus promoting their autonomy.
Resumo:
This work aims to understand the teaching of English at the Federal Institute of considering the recommendations of official and technical documents for the integrated secondary school and the perspective of the English teachers settled in one of the campuses of the Institute. It is also an objective of this research to infer as to what extent the perspective of teachers is articulated to the documental recommendations. For this purpose, several official and technical documents (LÜDKE; ANDRÉ, 1986), such as the PCNEMs (BRAZIL, 2000), the OCNEMs (BRAZIL, 2006) and the Political-Pedagogical Project of the Institute (IFRN, in press) were gathered, and a questionnaire was submitted to six teachers of English from one of the campuses of the institution. The theoretical references of the research include, among others, Bakhtin (1997; 1999), Widdowson (1991), Almeida Filho (2011; 2004), Celani (1988; 2009), Hutchinson and Waters (1987) and Dudley-Evans and St. John (1998). The results show that the teaching of English according to the documents predicts the instrumental use of the foreign language, but suggests the development of competences and skills as contextualized social practices, aimed at the education of the student as a professional-citizen. The perspective of teachers, in turn, points to a concern that the teaching of English serves as a tool for improving student life through the instrumental use of language as a means of accessing information and professional training. This finding reveals that the articulation between the documental recommendations and perspective of teachers does not go beyond what refers to the instrumental language teaching, since teachers do not show, when reporting their practices, the teaching of language as social practice, as mentioned in the legal texts
Resumo:
This study presents the results of a survey conducted in the area of English for Specific Purposes (ESP) in order to identify (1) the learning needs of students in a course in Tourism, their desires and lacks, at a federal university, with respect to use of English; (2) the needs of the present situation of teachers and the coordinator of that course as to the language; (3) the needs of the target situation of professionals (graduates) and companies with respect to this language. This research is a case study (STAKE, 1998; YIN, 2009) and was used for data collection, instruments such as questionnaires, semi-structured interviews, and document on the Tourism Course. To this end, it was adopted the theoretical basis for the constructs of English for Specific Purposes (ESP) Inglês para Fins Específicos (IFE) in Brazil, also known as Inglês Instrumental, whose foundation is based on the work by Hutchinson and Waters (1987), Robinson (1991), Dudley-Evans and St. John (1998), Celani, Deyes, Holmes, Scott (2006), among others, since this work is devoted to a specific area, Tourism. Results show that students opined the ability to prioritize reading and speaking into the classroom. Professionals reported that the latter is an indispensable tool for entering the labor market, yet they feel unprepared and need to attend English language courses in private language schools. The testimony of company executives also point to this deficiency. Finally, the present situation of teachers reveals that, while advocating the use of English in the classroom, this is not because students prefer their mother tongue. There is also an evident lack of needs analysis. Eventually, the coordinator said that there is some uncertainty as to the methodology, content and language skills worked, and the lack of interaction among teachers of English. It was concluded, therefore, it is important to conduct a needs analysis so that one can redesign a course that meets the different contextual needs: students, teachers, coordination, represented by the institutional needs, and the labor market
Resumo:
This dissertation aims at characterizing the practices as well as the effects of a teacher s feedback in oral conversation interaction with students in an English Language classroom at a Primary School, 6th Grade in Açu/RN, Brazil. Therefore, this study is based on Vygotsky s (1975) and Bruner´s (1976) researches, which state that the learning process is constructed through interaction between a more experienced individual (teacher, parents and friends) and a learner who plays an active role, a re-constructor of knowledge. It is also based on Ur´s (2006) and Brookhart s (2008) studies (among other authors in Applied Linguistic) who defend that the feedback process needs to be evaluative and formative since it sets interfaces with both students autonomy and learning improvement. Our study is based on qualitative, quantitative and interpretive researches, whose natural environment (the classroom) is a direct source of data generated in this research through field observations/note-taking as well as through the transcriptions of five English classes audio taped. This study shows the following results: the teacher still seems to accept the patterns of interaction in the classroom that correspond to the IRE process (Initiation, Response, Evaluation) in behaviorist patterns: (1) he speaks and determines the turns of speech; (2) the teacher asks more questions and directs the activities most of the time; (3) the teacher´s feedback presents the following types: questioning, modeling, repeated response, praise, depreciation, positive/negative and sarcasm feedback, whose functions are to assess students' performance based on the rightness and wrongness of their responses. Thus, this implies to state that the feedback does not seem to help students improvement in terms of acquiring knowledge because of its normative effects/roles. Therefore, it is the teacher´s role to give evaluative and formative feedback to a student so that he/she should advance in the learning of the language and in the construction of knowledge
Resumo:
This work aims at analyzing the activities presented in the book On Stage for junior high school students, which was selected by IFRN, as well as checking out the students interest for play activities. We have come from the point that playing activities can contribute to the increasing of motivation for the teaching of English (BROUGERE, 1999; WRIGHT, BETTERIDGE, BUCKBY, 2006; LANGRAN e PURCELL, 1994). At first place, our research is a document analysis and in second place, it is an action research. We have proposed two questionnaires for the participants of this work, all of them are High school students at IFRN-Campus Zona Norte, in order to check out their interests and the degree of motivation for the English learning before and after the carrying out of play activities. The obtained data also showed that the students became more motivated and interested in the classes after working with play activities, and most of the students agreed with the inclusion of these activities in the selected course book. The result of our work proved the benefits of play activities according to researches available in the literature about this subject. From the results acquired in the present work, we suggest that play activities should be included in English course books, even when they are addressed to High School teaching in order to help increasing the motivation for the learning of a foreign language
Resumo:
Some authors have suggested that learning tasks conducted in L2 classes can motivate learners in different ways. Similarly, Interactive Whiteboards (IWB) have already been linked as drivers to engagement and enthusiasm in L2 classes, which may cause some impact on affective variables that influence learning (e.g. motivation). This crosssectional mixed-methods study aims to understand how situational motivation caused by learning tasks mediated by the IWB impact participants. We seek to answer the following research questions: (1) How does motivation as a personality trait of the learner relate to his/her additional language learning performance?, (2) How does the type of learning task mediated by the IWB impact the learner s motivation?, (3) How does motivation vary along the learning task mediated by the IWB? and (4) What is the relation between the learning task motivation and the learners perception about the task mediated by the IWB? Data collection lasted four months with 29 learners from a private language school. The instruments used were the following: (a) an initial questionnaire (adapted from the Attitudes/Motivation Test Battery by GARDNER, 2004), (b) situation-specific on-line scales to assess learners motivation in three moments: before, during and after the task, and analyze how motivation varies along the task; (c) class observations and field notes resulting from these observations, (d) participants end-of-course grades to understand the connection between academic success and their motivational profiles and (e) a final questionnaire with the qualitative purpose to know learners perceptions about the tasks mediated by the IWB. Our theoretical framework is based on Task-Based Learning and cognitive aspects present in tasks (WILLIS, 1996; SKEHAN, 1996), theories on motivation and second language learning (GARDNER, 2001; DÖRNYEI e OTTÓ, 1998; DÖRNYEI, 2000; 2002) and conceptions about L2 learning mediated by technology (GIBSON, 2001; OLIVEIRA, 2001; MILLER et al, 2005). Our results do not point out to a significative correlation between learners end-of-course grades and their motivational profiles. However, they indicate that there is some variability in situational motivation along the tasks, even among learning tasks from the same type. Furthermore, they show that learners report different perceptions for each learning task and that the impact of the IWB on participants did not have a large proportion
Resumo:
This exploratory study aims to present some readings as Doyé (2003), Carrasco Perea (2003), Melo Araújo e Sá (2004), Chavagne (2009) and Alas-Martins (2010; 2011) which helped to confirm some ways for showing that a plurilingual environment can enable a trend in improving the understanding of written texts in the mother tongue, and can collaborate on a better perception of the world around a person with all their different nuances. The study describes the methodology and some results of our doctoral research that resulted in the insertion of the experimental discipline called Intercomprehension of Romanic Languages (ILR) in the curriculum in the city of Natal / RN / Brazil, and it was justified because of high functional illiteracy degree among young people up to 15 years old according to the educational data from IBGE research on 2010. The results were verified through an experimental action-research which was characterized by Lewin (1946); Nunan (1992); Thiollent (1994) and Trip (2005) in two schools: Professoara Terezinha Paulino de Lima (municipal school) and Professora Ana Julia de Carvalho Mousinho (State of Rio Grande do Norte), with 95 students from the final years of primary education. The corpus of this research was subjected to a series of condensed techniques like the nonparametric test from Kruskal and Wallis (1952) and the parametric test ANOVA as an effort to provide statistical significance to the analysis of the results indicated in the book of ILR activities. The research presented some skill views about reading comprehension of written texts according to perspective of Ringbow (1987), Giacobbe (1990), Alarcão (1991; 2009a and 2009b), Corder (1992), Castellotti (2001) and Degache (2003), and the possibilities of transfer these skills for learning Portuguese as pointed out by Meissner, Klein and Stegmann (2004); it indicates a positive trend towards the understanding of LM according to analyzing the scores of written tests and texts by participants in solving tasks
Resumo:
In this work, we have studied the acoustic phonon wave propagation within the periodic and quasiperiodic superlattices of Fibonacci type. These structures are formed by phononic crystals, whose periodicity allows the raise of regions known as stop bands, which prevent the phonon propagation throughout the structure for specific frequency values. This phenomenon allows the construction of acoustic filters with great technological potential. Our theoretical model were based on the method of the transfer matrix, thery acoustics phonons which describes the propagation of the transverse and longitudinal modes within a unit cell, linking them with the precedent cell in the multilayer structure. The transfer matrix is built taking into account the elastic and electromagnetic boundary conditions in the superllatice interfaces, and it is related to the coupled differential equation solutions (elastic and electromagnetic) that describe each model under consideration. We investigated the piezoelectric properties of GaN and AlN the nitride semiconductors, whose properties are important to applications in the semiconductor device industry. The calculations that characterize the piezoelectric system, depend strongly on the cubic (zinc-bend) and hexagonal (wurtzite) crystal symmetries, that are described the elastic and piezoelectric tensors. The investigation of the liquid Hg (mercury), Ga (gallium) and Ar (argon) systems in static conditions also using the classical theory of elasticity. Together with the Euler s equation of fluid mechanics they one solved to the solid/liquid and the liquid/liquid interfaces to obtain and discuss several interesting physical results. In particular, the acoustical filters obtained from these structures are again presented and their features discussed