22 resultados para Anastomosis grouping

em Universidade Federal do Rio Grande do Norte(UFRN)


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Os fatores de crescimento são substâncias moduladoras do processo de cicatrização. O fator de crescimento de fibroblastos básico (FCFß) liberado pelas plaquetas, macrófagos e pelos próprios fibroblastos, estimulam a proliferação celular, a produção de colágeno e de outros elementos da matriz celular, favorecendo o processo da cicatrização, mesmo em situações adversas, como diabetes e uso de corticosteróides. O presente estudo objetivou determinar a influência do FCFb no processo de cicatrização de anastomoses esofageanas em modelo de experimentação animal, avaliando-se a resistência à pressão,formação de tecido de granulação e deposição de colágeno. Método: Foram estudados dois grupos A e B,ambos com 10 ratos de linhagem Wistar, separados de forma aleatória, todos submetidos à secção e anastomose do esôfago por via abdominal. Nos animais do grupo A, foi feita aplicação tópica na linha de sutura de 10ng de FCFb. No grupo B (controle) foi aplicado igual volume de solução salina. Os animais foram sacrificados no 7º dia, o esôfago ressecado para teste de resistência da anastomose, estudo qualitativo do aporte de células inflamatórias, da angiogênese e quantificação do colágeno na zona da anastomose, através de sistema digital. Resultados: A densidade média dos parâmetros histológicos do grupo A foi 9095,51±1284,5, maior que no grupo B, que teve densidade 7162,4±1273,19 (p=0,013). A resistência da anastomose do grupo A teve a média 210±18,88 mmHg, significativamente maior que no grupo B, que atingiu o valor 157±29,55 mmHg (p=0,0024). Conclusão: Este estudo concluiu que o FCFß atuou melhorando a cicatrização e aumentando significativamente a resistência de anastomoses do esôfago realizadas em ratos

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The theoretical recital of the present study it is initiated of the evidence that the work occupies an important space in the man s life in way that the majority of the people works and passes great part of its time inside organizati ons. However, it is verified that the relation between man and work is becoming increasingly disagreement a time that the employees had started to complain work s routines, stress, not use all their potential and inadequate work s conditions. It can be observed by the way of Dejours (1994) studies. Thus, as contribution for the quality of work life s (QWL) studies the research developed here objectified to characterize the public employees quality of work life at EMATER -RN taking as reference an instrumen t of research synthesized from the typical academic literature of the subject. The synthesis of an ampler instrument is a necessity not taken care to the literature that treats on the subject but already perceived by some studies like Moraes et al (1990); Rodrigues (1989); Siqueira & Coleta (1989); Moraes et al (1992); Carvalho & Souza (2003); El -Aouar & Souza (2003) and Mourão, Kilimnick & Fernandes (2005); Adorno, Marques & Borges (2005) amongst others. These studies point out weak points of the existing models in the QWL s literature, as well as they recommend the elaboration of a model more flexible, that contemplates Brazilian cultural characteristics, and that contemplates the entire variable studied in the main existing models. For reach this objectiv e the adopted methodology was characterized as a case study with collected data in qualitative and quantitative way. Questionnaires and comments had been used as sources of evidences. These evidences had been tabulated through of statistical package SPSS ( Statistical Package for Social Science), in which the main technique of multivariate analysis used were the factorial analysis. As for the gotten results, it was verified the grouping of the quality of work life s indicators in 11 factors which are: Work s execution, Individual accomplishment, Work s equity, Relation individual and organization, Work s organization, Adequacy of the remuneration, Relation between head and subordinate, Effectiveness of the communication and the learning, Relation between work and personal life, Participation and Effectiveness of the work processes. Whatever to the characterization of the EMATER -RN s quality of work life it was clearly that to the measure that the satisfaction s evaluation with the QWL in the organization walks to intrinsic factors for extrinsic factors this level of satisfaction goes diminishing what points to the importance to improve these extrinsic factors in the institution. In summary it is possible to conclude that the organization studied has offered a significant set of referring variable to the quality of work life of the individual

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This study deals with the participation of the dance of São Gonçalo of the Mussuca town/SE, in the process of construction of the ethnic identity among this social group. The Mussuca is a grouping recognized as afro-descendents, linked with black enslaved people in the valley of the Cotinguiba region. The collective memory functions as a drive of this linking with the past and if it makes to elaborate narratives on this descent. The objective of this study was to investigate the ways the rite went through to constitute itself as an element of ethnic representation. Internal and external agents had been identified who had participated in different contexts. By means of an ethnographic work we ve reached some aspects of the local structure social which demonstrated the contradictions through the social relations of the group. This process of ethnic autorecognition presents the kinship and the space question as definers of the social arrangements which establish its ethnic boundaries

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The increasing use of fossil fuels in line with cities demographic explosion carries out to huge environmental impact in society. For mitigate these social impacts, regulatory requirements have positively influenced the environmental consciousness of society, as well as, the strategic behavior of businesses. Along with this environmental awareness, the regulatory organs have conquered and formulated new laws to control potentially polluting activities, mostly in the gas stations sector. Seeking for increasing market competitiveness, this sector needs to quickly respond to internal and external pressures, adapting to the new standards required in a strategic way to get the Green Badge . Gas stations have incorporated new strategies to attract and retain new customers whom present increasingly social demand. In the social dimension, these projects help the local economy by generating jobs and income distribution. In this survey, the present research aims to align the social, economic and environmental dimensions to set the sustainable performance indicators at Gas Stations sector in the city of Natal/RN. The Sustainable Balanced Scorecard (SBSC) framework was create with a set of indicators for mapping the production process of gas stations. This mapping aimed at identifying operational inefficiencies through multidimensional indicators. To carry out this research, was developed a system for evaluating the sustainability performance with application of Data Envelopment Analysis (DEA) through a quantitative method approach to detect system s efficiency level. In order to understand the systemic complexity, sub organizational processes were analyzed by the technique Network Data Envelopment Analysis (NDEA) figuring their micro activities to identify and diagnose the real causes of overall inefficiency. The sample size comprised 33 Gas stations and the conceptual model included 15 indicators distributed in the three dimensions of sustainability: social, environmental and economic. These three dimensions were measured by means of classical models DEA-CCR input oriented. To unify performance score of individual dimensions, was designed a unique grouping index based upon two means: arithmetic and weighted. After this, another analysis was performed to measure the four perspectives of SBSC: learning and growth, internal processes, customers, and financial, unifying, by averaging the performance scores. NDEA results showed that no company was assessed with excellence in sustainability performance. Some NDEA higher efficiency Gas Stations proved to be inefficient under certain perspectives of SBSC. In the sequence, a comparative sustainable performance and assessment analyzes among the gas station was done, enabling entrepreneurs evaluate their performance in the market competitors. Diagnoses were also obtained to support the decision making of entrepreneurs in improving the management of organizational resources and promote guidelines the regulators. Finally, the average index of sustainable performance was 69.42%, representing the efforts of the environmental suitability of the Gas station. This results point out a significant awareness of this segment, but it still needs further action to enhance sustainability in the long term

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The composition of ichthyofauna discarded by trawling shrimping, their reproductive status and feeding ecology were studied on the beaches of Basin Rio Grande do Norte, Brazil. Fish were collected monthly in the year of 2012. During biometrics, portions of the digestive tract and of gonads were removed, fixed in formalin 10% and Bouin, respectively, for be submitted to histological processing by the techniques of hematoxylin-eosin. Stomach content analyzes were performed using the methods of Frequency of Occurrence and Volumetric and was calculated the repletion index. Throughout the study period were recorded a total of 49 species. The fish assemblages differed between sections monitoring, with the highest abundance, biomass and indices of richness and diversity in sections B, D and C. Already the excerpt A, showed higher values for dominance and equitability. In the cluster analysis according to the faunal similarity was observed the formation of three groups: group I formed by excerpts B and D, group II by excerpt C and group III formed by excerpt A. The assessment of reproductive stage revealed that the fish assemblages discarded by trawling are composed mainly of juveniles. Regarding the feeding ecology, the species Larimus breviceps, Menticirrhus littoralis and Pomadasys corvinaeformis characterized as carnivorous with tendency to carcinofagia. Already Conodon nobilis characterized as carnivorous with tendency to piscivory, but all proved generalist-opportunistic with increase of feeding activity during drought. The dendrogram of grouping of the species developed based on the food items used shows the formation of four groups: Group I consists of species that feed mainly of "gastropod" and "sediment"; group II of "teleost fish"; the group III of "crustacea" and group IV of "echinodermata" and "bivalve". The anatomical and histological characteristics of the digestive tract were consistent with the dietary habits of the analyzed species. In this context, the Costa Branca of Rio Grande do Norte can be considered a feeding site and recruitment for juveniles, which, opportunistically, utilize resources associated with the background

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The thesis entitled The administrative reform and social political management in Mossoró: the institutional and social staff's falacy. Comprehends a moment of apprehensiveness and analysis in the reestrcturing process of the city, whose process will show the formation of strategies and deployment of its relation with the social political affectiveness. It represents a single moment in the approach of such a kind of experience in the city. The analysis starts from the third mandate of the Mayor Rosalba Ciarlini Rosado, during the quadriennium 2001/2004, for being the time in which the public management got materialized, such as in the operational way of the social politics. For that, we delimitate this study in two distinct moments: the first one refers to the reform elaboration from the creation of the additional law nº 001/2000 GP/PMM: the second one refers to a practical reform from the social and institutional staff's speech. Within that scenary it was seen that the approaching, though partially, the State Reform and, consequently, the master plan of the state apparatus, which were made of theoretical matrices of such a project locally. However, that is a complex experience, that required the use of field and documental research for the proposed investigation and at the same time, prove the guiding hypothesis of it, what means a grouping of areas like: education, healthy, and social development in only one department City Citizenship Department that is able to materialize a new intitutional arrangement, according to the management principles in the public administration at the govern local level, configuring a reform and not just an institutional adequacy. In that context, it got necessary to apprehending the institutional and social actors' falacy as a way to prove or not the presented hypothesis. Among the first staff, we have the mayor's direct leaders and advisors' perception that express the politcal administrative aspects of the reform and, in the second, the perception of the political view of what has changed concerning the management of the social politics

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This study want to know how Josué de Castro, the two terms of a congressman, participated in the Brazilian political-ideological debate of the 1950s. For this, search the 61 speeches in the plenary of the House of Representatives and its 14 projects, analyzing them as historical documents that describe an experience, which enables the central category amalgamated the subject and his time, which breaks up the possibilities of new social practices. Unity of action and reflection, the experience of Castro in the Brazilian parliament has got on the basis of a previous flow experiences in the political-institutional and scientific. Together with the personal history, the political intellectual scenario of his time was another variable considered in the first chapter of this work. In the second chapter did an analysis of 32 speeches and projects of the first term of Josué de Castro, grouping them by thematic affinities. The 43 for the second term were discussed in the third chapter, leaving the final considerations answer the research objectives: What are the main interlocutors? What are your political positions? What are the points of rupture and continuity in his political career? Josué de Castro spoke to the Brazilian state directly to the president, some ministers and to the SUDENE, the ONU appears indirectly through the reports of his participations. His political position was a national-developmentalist who embraced the cause of self-determination of the countries, anti-imperialism, agrarian reform and regional planning, strongly inspired by Celso Furtado and San Tiago Dantas. Castro often has blended a liberal and Marxist terminology, relying on different ideologies to do support his fight against hunger

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In this paper artificial neural network (ANN) based on supervised and unsupervised algorithms were investigated for use in the study of rheological parameters of solid pharmaceutical excipients, in order to develop computational tools for manufacturing solid dosage forms. Among four supervised neural networks investigated, the best learning performance was achieved by a feedfoward multilayer perceptron whose architectures was composed by eight neurons in the input layer, sixteen neurons in the hidden layer and one neuron in the output layer. Learning and predictive performance relative to repose angle was poor while to Carr index and Hausner ratio (CI and HR, respectively) showed very good fitting capacity and learning, therefore HR and CI were considered suitable descriptors for the next stage of development of supervised ANNs. Clustering capacity was evaluated for five unsupervised strategies. Network based on purely unsupervised competitive strategies, classic "Winner-Take-All", "Frequency-Sensitive Competitive Learning" and "Rival-Penalize Competitive Learning" (WTA, FSCL and RPCL, respectively) were able to perform clustering from database, however this classification was very poor, showing severe classification errors by grouping data with conflicting properties into the same cluster or even the same neuron. On the other hand it could not be established what was the criteria adopted by the neural network for those clustering. Self-Organizing Maps (SOM) and Neural Gas (NG) networks showed better clustering capacity. Both have recognized the two major groupings of data corresponding to lactose (LAC) and cellulose (CEL). However, SOM showed some errors in classify data from minority excipients, magnesium stearate (EMG) , talc (TLC) and attapulgite (ATP). NG network in turn performed a very consistent classification of data and solve the misclassification of SOM, being the most appropriate network for classifying data of the study. The use of NG network in pharmaceutical technology was still unpublished. NG therefore has great potential for use in the development of software for use in automated classification systems of pharmaceutical powders and as a new tool for mining and clustering data in drug development

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This investigation had the teacher as object of study, whose objective was to know and analyze the teacher‟s Social Representations (SR) shared by undergraduates, as from images of this professional (teachers´ photos of several levels and school systems). It was searched out the process of depreciation or estimation, in which the teaching profession has been passing, trying to catch, specifically, possible existing correlations among such SR and the reflections in the attitudes developed by these students about their own development and professional practice. The data collection was carried out at the Federal University of Piauí Teresina with 165 undergraduates (15 from each course). It was applied a semi-structured interview, mediated by iconographic grouping (SALES, 2000, 2007), outlining a methodological widening of the studies fulfilled by (ROAZZI, 1995). It was used the function Factor Analysis, available in the SPSS (Statistical Package for the Social Sciences) for the analysis of the quantitative data, and it was proceeded a content analysis through the categorical analysis technique (BARDIN, 1977) for the analytical procedures of the qualitative data. It was resorted to the SR theory (MOSCOVICI, 1978) for the data interpretation and the Theory of Signs (PEIRCE. 1995) in the understanding of the decodification processes of signs that were present in the photos worked. It became evident that the undergraduates perceived the teaching profession inserted in a hierarchical scale of values (positive/negative), directly related to the school system and the teaching level, in which the teacher works. Most undergraduates share teacher‟s SR of negative content, consolidating the hegemonic SR about the teacher‟s social depreciation, although some of them imagine themselves, in the future, inserted among the teachers more appraised, showing that the SR orientate the positive and negative attitudes about the teacher. The presence of SR that mobilize the interviewers‟ attitudes in opposite senses related to the teacher, offer evidence of the necessity of future studies that can use a methodology more focused to understand other motivation factors that the undergraduates give evidence of having to the course they have chosen, besides the ones inferred by the SR caught in this investigation, as well as to establish a correlation between the teacher‟s SR (positive and negative) and the social economic level of the interviewers that share them. Such data revealed itself necessary since the literature signalizes for a relation between the course chosen and the applicant‟s social-economic level, and that the applicants‟ objective conditions to the licenciature courses are related to the subjective hopes that their group supplies

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This study investigates the contributions of reading literature for the development of creative thinking in childhood. Its relevance consists in exploring practices that contemplate the creative thinking development in apprentices at school space and understanding the literature like a significant way to promote the creative thinking. The study is connected to the qualitaty strand. The exploratory observation and the intervention were adopted as research techniques. The field diary and the audio and video recording of the reading sections were adopted as methodological instruments. The research was conducted in the application s college from the Federal University of Rio Grande do Norte, in a 1th grade class, with 18 students between 6 and 7 years old. During the intervention, 8 readind class happened, with varied strategies and literary genres. The reading sessions were conducted through the principles of scaffolding, defended by Graves and Graves (1995). The corpus is made of speaks episodes, whose encoding semantics allowed the grouping into two central categories: divergent thinking and coauthoring of literary reader. It was taken as a theoretical framework the studies of Amarilha (2011; 2006; 2001; 1991; 1993; 1994), Alencar (2001), Coelho (2000; 1997), Culler (1999), De Masi (2005), Gallo (2000), Guilford (1977), Iser (1996), Jouve (2002), Kneller (1978), Martínez (1997), Smith (2003), Stierle (1979), Vigotski (2009; 1998), Wechsler; Nakano (2003; 2002). The analysis points to the formation of creative individuals in the classroom, through the reading of literature. Reposition the literary education front of the new social demands. Resizes the function of school in children s development, considering the children s skill in exploring, testing hypotheses and making use of their creative thinking, in climate of freedom mental. It signals, in this way, the teacher like a mediator, promoting a favorable to the development of creative thinking environment, a stimulating atmosphere, which enhances the expression of creative thinking in community

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The environment of Intensive Care Unit (ICU) is commonly referred to as a place where caring is inextricably linked to high technology. The care in ICU often changes the patient into a taxpayer being left apart from its complexity and sometimes seen through a reductionist perspective. Thus, studies circa the care process are needed oriented from a historical ransom, raising the prospect of a more centralized human care. Hence, this study aimed to analyze the care process in a nursing intensive care unit from the perspective of the professional, family and patients. The study is characterized from a qualitative, descriptive and exploratory methodological approach. The actors were participating nursing professionals, patients and family members of an intensive care unit of Mossoró / RN. Data were collected in the period of May-June 2011, through interviews and observation of activities performed by nursing professionals, and their records in the chart. Data analysis was divided into topics and subtopics representing the phases and shapes that formed the collection. The analysis and discussion of the interviews were based on Bardin's proposal, when we created categories from a process of sorting and grouping criteria adequately defined. The observation of nursing records intended to observe the emphasis which is described in those notes as well as their consistency with practice of FCN and resolution 358/2009. The analysis showed that the nursing staff also performs work focused on mechanized activities and technical-bureaucratic institution that seem to override the needs of patients. In an overview, the care provided by professionals occurs either fragmented or insipient, however there is a service that involves other aspects beyond technical-curative practice, considering that major attention is given to the family and patient, focused on the concern of Nursing guiding their actions in not only the performance of procedures. However, the process of humanizing not always ends with an engagement between professional and patient, which mischaracterizes the true meaning of human care. The records also showed a tendency to focus on caring in a positivist line, where, in most cases, the factors of the disease and the obligation to meet the productivity have overshadowed other relevant aspects to a holistic understanding of caring. Regarding FCN Resolution No. 358/2009, which guides a systematization of nursing care, it is confirmed a technical view, a fragmented and superficial view of the patient, as well as a weakness of care, caused by ignorance and unpreparedness of the entire team. The perspective of caring demonstrates a reality with dialectic between what is proposed in a humane nursing and what happens in this performance space. Besides, it was shown a daily full of important considerations that arise in professional practice, in their views and also those people who were participants in the process

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This study aimed to analyze stress on nursing staff of intensive care at the Teaching Hospital Onofre Lopes. The study sample consisted of thirty-eight (38) nursing professionals, including technicians and nurses working in the ICU of the hospital Data were collected between September to November 2011 in two stages.The first was the application of the Lipp Stress Symptoms Inventory (LSSI), which allowed us to measure the stress phase in which each team member was. After that, data were tabulated in Microsoft Excel spreadsheets and analyzed according to the 2010 inventory guidelines proposed by the author. After this analysis it was possible to complete the second phase of the research, which consisted of a semi-structured interview designed for those workers who were in the second phase of stress, resistance. Data analysis was based on Bardin 2004 content analysis, enabling the creation of categories based on grouping the ideas present in the interviewees' statements. It was found that the study population was mostly female (78.9%) aged from 30 to 39 years (50%), married (52.3%) and with dual-employment (65.7%). The most predominant phase, according to the Lipp inventory, was the stress resistance, present in 44.7% of the team and having as most predominant physical symptoms the constant feeling of physical exhaustion, verified in 16.8% of the participants, and psychological, the excessive irritability and emotional sensitivity in 26.3%. Regarding the qualitative data it was possible to establish three categories and four subcategories, with the following categories: the stressors of the workplace, overwork and the interpersonal relationships of the nursing staff in the ICU. And as subcategories: Routine care in the ICU; Pressures and Individual Charges; double journey: professional reflections on daily life, the night shift nursing staff and the body suffers, the manifestations of stress; deficient communication between team members. Thus, this study allowed the visualization of the stress phenomenon on nursing staff of the Teaching Hospital Onofre Lopes as a kaleidoscope of thoughts, feelings and experiences perceived by these professionals in different areas of their lives. It was also verified that the strengthening of the stress theme among nursing professionals need to be exploited and stimulated in several nursing areas of discussion so these workers are encouraged to take better care of themselves so they can take care of others health

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The current study strives to address the interpersonal relationships of the nursing team from the perspective of the communicative action, by contributing to the health work process. It aims to analyze the interpersonal relationships of the nursing team in its work environment. This is a descriptive study with a qualitative approach. Data collection wal held from interviews, guided by a script with open questions. The study was conducted at a state hospital in the city of Natal/RN/Brazil. The research subjects were the workers of the nursing team, including nurses, nursing technicians and nursing assistants, totaling 16 subjects. The capture of information was performed in April 2012. The project was approved by the Ethics Research Committee, under CEP/UFRN protocol n. º 262/11 and Certificate of Presentation for Ethical Consideration n. º 0289.0.051.000-11. The analysis was performed from the categories that emerged from the research through a dialogue with the authors studied in the theoretical framework of the Theory of communicative action , by Jürgen Habermas, as well as The changing in the world of work, by Ricardo Antunes, and Characterization of the team , by Marina Peduzzi. The outocomes point out that the interpersonal relationship of the nursing team is very troubled, with no interaction among the individuals involved in this process, among themselves and with other health professionals. We have developed a particular concept about team, which is comprised of three essential elements: multiplicity of individuals, common objective and heterogeneity. In the studied environment, it was realized the existence of grouping teams. The interpersonal relationship of the nursing can be a facilitator or an obstacle in the workplace in such a way that causes positive or negative consequences, both to the health workers, and to the sicks. In this context, the interviewees have intensified their viewpoints with regard to the weaknesses that permeate the nursing relationship, by pointing them more frequently than the strengths. The work conditions have signaled a failing situation, which is evidenced by the constant improvisation process before the lack of human and material resources, low wages, deficit in recognizing the nursing worker, and physical and emotional wear, by creating a professional exhaustion. The devaluation of the worker also became a strong factor for this study, because it was characterized a reason of job dissatisfaction, due to the lack of valuation policies, which should be prepared by the institution or, even, they are unknown by the worker itself. The worker participation in the design of these policies has emerged as a relevant factor. The poor work conditions lead the worker to a process of professional demotivation and dissatisfaction, by causing the feeling of devaluation within its work environment. Hence, it was found in this research that the lack of communication leads to situations of inadequate interpersonal relationships, which are creators of an unsuitable environment for the performance of the nursing team

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In this work we present a new clustering method that groups up points of a data set in classes. The method is based in a algorithm to link auxiliary clusters that are obtained using traditional vector quantization techniques. It is described some approaches during the development of the work that are based in measures of distances or dissimilarities (divergence) between the auxiliary clusters. This new method uses only two a priori information, the number of auxiliary clusters Na and a threshold distance dt that will be used to decide about the linkage or not of the auxiliary clusters. The number os classes could be automatically found by the method, that do it based in the chosen threshold distance dt, or it is given as additional information to help in the choice of the correct threshold. Some analysis are made and the results are compared with traditional clustering methods. In this work different dissimilarities metrics are analyzed and a new one is proposed based on the concept of negentropy. Besides grouping points of a set in classes, it is proposed a method to statistical modeling the classes aiming to obtain a expression to the probability of a point to belong to one of the classes. Experiments with several values of Na e dt are made in tests sets and the results are analyzed aiming to study the robustness of the method and to consider heuristics to the choice of the correct threshold. During this work it is explored the aspects of information theory applied to the calculation of the divergences. It will be explored specifically the different measures of information and divergence using the Rényi entropy. The results using the different metrics are compared and commented. The work also has appendix where are exposed real applications using the proposed method

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Lemon sharks, Negaprion brevirostris, are common in the Fernando de Noronha Archipelago, but detailed information about the species in this site is lacking. The aim of this study was to describe the spatial distribution, grouping behavior, habitat use and behavioral ecology of juvenile lemon sharks in the archipelago, and their interaction with some environmental and ecological factors. During 2006 and 2007, the presence and spatial distribution of juvenile sharks were quantified through scuba diving and snorkeling at several sites of the archipelago. In 2008 the habitat use of juvenile sharks was quantified through visual census while snorkeling along 300 x 8 m strip transects. During these transects the grouping behavior of lemon sharks was quantified by ad libitum. Results indicate that Fernando de Noronha Archipelago is used as a nursery area for lemon sharks, and the parturition occurs from November to April. Juveniles preferred using shallower areas available by the tide variation and formed groups only in the presence of adult conspecifics. This preference for shallower habitats and the group behavior probably are anti-predatory tactics used by juvenile lemon sharks, in response to the low availability of shelter and high predation risk of the studied areas. Quantifications of prey availability and predation risk of juveniles showed that, in general, lemon sharks are trading-off food by security and investing in sites with higher possibility of energetic return. Behavioral observations enabled to record juvenile carangid fishes following juvenile lemon sharks, remora host-parasite and juvenile sharks foraging on schools of herrings and octopuses. We also recorded the behavior of juvenile sharks following conspecifics of similar size, circling with two or three individuals and smaller individuals giving way to larger juveniles. When adults are present, juvenile lemon sharks are more social than solitary, indicating that predation is one of the factors that contribute to social behaviors of the species. Results also suggest that when grouped the juveniles have a hierarchical organization according to body size. Furthermore, observation of large adult females with several fresh mating bites and scars in the same habitats used by juvenile lemon sharks, indicates that Fernando de Noronha Archipelago is used as nursery and mating grounds by this species