23 resultados para Discordância

em Universidade Federal do Rio Grande do Norte(UFRN)


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A síndrome de Cogan é entidade multissistêmica rara caracterizada por ceratite intersticial associada à disfunção áudio-vestibular e possível surdez irreversível classificada em duas formas clínicas: típica e atípica. Há discordância na literatura quanto à presença de acometimento corneano na forma atípica. Uma paciente de 32 anos queixando-se de hiperemia e dor ocular, fotofobia e baixa da acuidade visual no olho direito, associada à perda súbita de audição à esquerda, vômitos, diarréia, oligúria, dor na orofaringe e febre. História prévia de semelhante acometimento do olho esquerdo e audição direita. Havia intensa hiperemia conjuntival, esclerite nodular, episclerite e infiltrados circulares no estroma corneano. A paciente recebeu pulsoterapia com metilprednisolona e ciclofosfamida. Evoluiu com grande melhora ocular, porém com resposta auditiva pobre. O caso reportado pode constituir forma típica da síndrome de Cogan (de acordo com autores que defendem o nãoacometimento corneano na forma atípica) com alguns achados característicos da forma atípica ou um caso da forma atípica da síndrome de Cogan (para aqueles que defendem o acometimento corneano na forma atípica). O diagnóstico diferencial também é discutido

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Ethics on scientific research is approached and often discussed in several areas of knowledge connected to health. In the Administration area there are very few studies which approach the topic of ethics on research. The present paper tried to fill in this gap in the production of knowledge about the topic, investigating how the ethical principles found in the literature and in the codes of conduct are noticed and taken into account in Administration research activities developed by acting researchers in Administration Post Graduation Programs. Theoretically speaking, the study was based mainly on the approaches by Creswell (2007) and Bell and Bryman (2007), which discuss the research ethical principles. Methodologically speaking it was all about an exploratory kind of study, with qualitative research approach. Upon data collection, personal interviews were made aiming at its depth and focus groups were formed. The first stage had interviews with four experienced researchers who took part on a teaching and researching event and on the second stage we used the focus group technique. The focus groups were done in four college institutions along with the post graduation programs in Administration in the states of Rio Grande do Norte, Paraíba and Pernambuco, in Brazil. The results suggest the existence of general principles and parameters for the scientific research recommended in the literature and on official resolution. However, in the Administration area, there are only a few recommendations of good practices when it comes to submitting articles for scientific publications but we found no guidance with ethical principles and parameters which cover all the activities in the scientific research and which specifically meet the research particularities in Administration. The main ethical dilemma pointed by the researchers refers to ethical questions which arise at the time of data collection and on disclosing the results. Most researchers do not know the guidelines and the ethical norms on ethics about research that we have in our country neither do they send in their projects to the research ethics committee. When dilemma arises, they decide the ethical question based on their values and common sense. These elements confirm the thesis that the researcher s procedure in the research activities in Administration is predominantly signed by personal values or by common sense and less by ethical principles, whether by not knowing the normative instruments related to ethics or by disagreeing with any disciplining rules on ethical behavior in the research

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A escassez de instrumentos para a avaliação e a triagem da doença de Alzheimer, (DA), notadamente denominados de rastreio, com características de padronização e validados para o Nordeste, motivou este Estudo. Visando à triagem de uma etapa mais leve da doença e encaminhamento precoce ao tratamento multidisciplinar foi elaborado o Teste de Rastreio da Doença de Alzheimer com Provérbios (TRDAP), a partir de um Jogo de Memória de Provérbios, construído como recurso terapêutico ocupacional. Está composto de três etapas conforme a função neuropsicológica avaliada, a A (memória de curto prazo), B (funções executivas e linguagem) e C (memória episódica), além do reconhecimento de provérbios. O Estudo foi realizado em uma amostra de conveniência, com 91 idosos (28 DA e 63 controles), a partir de 60 anos, com um ou mais anos de escolaridade. Foram controladas as variáveis, como doenças intercorrentes ou déficits sensoriais que pudessem comprometer o desempenho dos pacientes, nos testes. O protocolo constou de oito testes selecionados por especialistas: Miniexame do Estado Mental (para validade convergente), Escala de Depressão Geriátrica EDG (validade discriminante), Lista de Palavras, Fluência Verbal, Span de Dígitos, Figura Neuropsi, Teste do Relógio, Atividade de Vida Diária e Instrumental. Os resultados confirmaram a validade de construto convergente e discriminante, assim como a relação significativa (p<0,005) com todos os testes, exceto com o EDG. Quanto à validade concorrente, não houve discordância com o critério da avaliação médica observou-se consistência interna aceitável, conferindo confiabilidade no instrumento, o que não ocorreu com MEEM. Tais resultados permitem afirmar que o TRDAP possui características psicométricas, adequadas ao rastreio da fase leve da DA para população estudada

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Lithiasis is considered a public health issue due to its high prevalence and rates of recurrence. Objective: To identify risk factors for lithiasis in kidney stone patients from Fortaleza, Brazil. In the first stage of the study, the medical records of 197 patients with urinary lithiasis covering the period 1996 2006 were analyzed with regard to clinical and metabolic data. In the second stage, 340 kidney stones were submitted to morphological examination under 10x magnification. According to the external morphology and the cut surface, the stones were classified as pure or mixed, and major and minor components were identified. In addition, the stone fragments of 25 patients treated with lithotripsy were submitted to morphological analysis. In the third stage, a subsample of 50 stones was used in a double-blind comparison of morphological and chemical findings. Results were expressed as concordant, partly concordant (discordant for minor components) or discordant (discordant for major components). The average age of first symptoms was 35.8±13.3 years, with no significant difference between the genders. The male/female ratio was 1:1.7. Recurrence was reported in 53.3% of cases. The main metabolic changes observed were hypernatriuria (80.7%), hypercalciuria (48.7%), low urine volume (43.7%), hyperoxaluria (30.5%) and hyperuricosuria (17.3%). Pure stones represented 34.7% of the total sample of 340 stones. The most common route of elimination was spontaneous for pure stones (49.1%) and surgical for mixed stones (50.5%). Pure stones consisted most frequently of calcium oxalate (OxCa) (59.3%) and uric acid (UA) (23.7%), the former prevalent in women, the latter prevalent in men. The most frequently observed component in mixed stones was OxCa (67.1%), followed by carbapatite (11.2%) and struvite (7.9%). The main components were OxCa and UA for men, and carbapatite and struvite for women. Nearly half (48%) the 25 analyzed fragments were pure, consisting of calcium oxalate dihydrate (COD) (56%), calcium oxalate monohydrate (COM) (48%), phosphate (32%) and UA (20%). Four patients (16%) had infectious stones. In the chemical analysis of the subsample of 50 stones, the most 64 frequently observed major components were calcium (70%), oxalate (66%), ammonium (56%), urate (28%) and carbonate (24%). In the morphological analysis, the main components were calcium and magnesium phosphate (32%), COM (24%), UA (20%), COD (18%) and cystine (6%). Morphological and chemical findings were totally concordant for 38% of the stones, partly concordant in 52% and discordant in 10%. Conclusion: The risk factors for lithiasis in kidney stone patients from Fortaleza (Brazil) were hyperoxaluria, hypercalciuria with or without hypernatriuria, hyperuricosuria and low urine volume

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This study aimed to validate the technology at Bed Bath System, in view of bedridden elderly and their caregivers, with a view to transforming the conventional paradigm regarding the practice of bodily hygiene held in bath chairs adapted in long-stay institutions for the elderly. This is an experimental study involving 51 (fifty one) elderly and 17 (seventeen) caregivers of three long-stay institutions for the elderly of the city of João Pessoa. For data collection, applied initially to cognitive assessment scale Mini Mental State Examination, with the aim of tracking the subject group of elderly cognitively able to participate in the study. In the second phase, to measure the percentage of agreement and disagreement about the attributes of the subjects of the shower chair and adapted the system for bed bath, used a questionnaire with closed questions, Likert scale model of four (4) points, with a good reliability index (0.728), estimated by alpha conbrach, evidenced by the Wilcoxon test a significant difference (P<0.05) between the responses of seniors and caregivers about the attributes involving technology system in bath bed and bath chair adapted, confirming the perspective of the subjects that the two systems differ significantly. However, the system bed bath got greater degree of agreement for their use, characterizing this system is a technology that makes the differential bed bath pleasurable action, quality and humanized

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This study aimed to validate the contents of an Instrument for Nursing Consultation in the Home Visit of people with Spinal Cord Injury (INCEVDOP-LM), based on the Self-Care Deficit Theory. The methodological development study was conducted with spinal cord injured (SCI) people ascribed in the Family Health Units the city of Natal/RN/Brazil, and with the nurses of these institutions. The study was conducted from Januray 2012 to January 2013 in two phases: the first aimed to identify the need for self-care of persons with SCI, and the second to develop and validate the INCEVDOP-LM. The first phase consisted of a census study of people with SCI living in Natal/RN. In the second phase, a non-probabilistic convencience sample of subjects was selected to form two groups: First stage - Group 1 of the first stage was comprised by 73 adults with SCI diagnosed with paraplegia or tetraplegia, with cognitive function preserved and that were registered to some family health unit; Group 2 of the Second phase was composed of six experts that were nurses with doctoral formation, scientific experience in the area of technology development or assistance to persons with SCI, and with publications in periodicals Qualis A2. Data collection of the first phase was conducted through home visits of people with SCI that responded three instruments: Questionnaire I (comprised of demographic and socioeconomic variables), The Competency Rating Scale for Self-care (ASA) and the Barthel Index (an instrument for evaluation of functional capacity). The research for the second phase was conducted in two stages: I-construction of the INCEVDOP LM; II-validation of the INCEVDOP-LM. The instrument and an evaluation form were forwarded to the experts for the validation. The correlations between the responses were analyzed by the Kappa test, with accepting values of>0.75. The evaluation criteria were: organization, clarity, simplicity, readability, appropriateness of vocabulary, objectivity, accuracy, reliability and suitability and the positive responses with frequency values of≥90% were considered excellent. The chi-square test was used to investigate the differences between proportions. The study attended to the principles of Human Rights CNS Resolution 196/96. Results were reported by means of four articles derived from the study. The findings indicate that the items that showed disagreement among experts (k=0.02) were diagnoses, interventions and evaluation of the nursing features pertaining to the domains of Nutrition, Hygiene, Elimination, Physical, Social and Psychological, and of the Ability to perform work activities feature. Agreement among the experts were reported for the other items, with kappa ranging from 0.72 to 1. After removing items with disagreement, all criteria achieved excellent rates and no significant differences were observed between the proportions of responses of evaluation of experts (p>0.05). We conclude that the instrument shows validity to serve as a guide for nurses to conduct a systematic consultation during the home visit to people with spinal cord injury, with emphasis on self-care. The instrument must go through other levels of validation when applied in the clinical setting

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This study aims to analyze and compare the opinion of professionals, managers and users about the mental health care in the Family Health Strategy (FHS). It is characterized as an Operations Research or Health System Research with a cross-sectional design and a descriptive quantitative nature. The study was developed from the application of the Opinion Measurement Scale allied to techniques of observation and structured interview in the city of Parnamirim / RN. The sample consists of 409 subjects, 209 professionals of the Family Health Strategy, 30 of the Oral Health Strategy, 19 of the Family Health Support Center, 24 directors of Basic Health Units, plus 68 users with mental disorders and 59 caregivers, respecting the ethical parameters of Resolution 196/96 of the National Health Council, trial registration number: CAAE 0003.0.051.000-11. Quantitative data were submitted to the Epi-info 3.5.2 for analysis. The network of mental health in Parnamirim involves the flow between the FHS, Psychosocial Care Centers, clinics and hospitals, having as main barriers the fragility of the referral and counter-referral system, of the municipal health conferences, of the FHS teams by the limitations in material and human resources as well as the population´s lack of acknowledge about the organization of the mental health network, issues that affect the integral attention. Even though the FHS professionals recognize the importance of their actions, they question their role in mental health care, experiencing difficulties in accessing psychiatric services (76.5%). Although most agree that the mentally ill is best treated in the family than in hospital (65.2%), the community health workers were the predominant category in the partial or total disagreement of this statement (40.8%), who is the professional in greater contact with the family. Nevertheless the caregivers miss the support of the FHS as the main focus of attention is on revenue control. The views of professionals, mental patients and caregivers converged in several statements, showing the main weaknesses to be focused by the mental health network of the city, as the perceptions that: (a) physical strength is needed to take care of mental patients for its tendency to aggression, requiring it to stay in the sanatorium for representing danger to society, (b) only a psychiatrist can help the person with emotional problems, (c) the user of alcohol and drugs does not necessarily develop mental illness, (d) the access barriers and doubts about the quality of psychiatric services, (e) caring of a mental health patient does not bring suffering to professionals. Therefore, the commitment to consensus building, monitoring and evaluation of the network are important mechanisms for an effective management system, reflecting in the importance of strengthening the health conferences and approximating different institutions. The results reinforce the importance of strengthening primary care through programs of continuing education focusing on the actions and functions of professionals in accordance with its competences and duties what contribute to the organization and response of mental health care, favoring user´s care and the promotion of family health

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Recently, Brazilian scientific production has increased greatly, due to demands for productivity from scientific agencies. However, this high increases requires a more qualified production, since it s essential that publications are relevant and original. In the psychological field, the assessment scientific journals of the CAPES/ANPEPP Commission had a strong effect on the scientific community and raised questions about the chosen evaluation method. Considering this impact, the aim of this research is a meta-analysis on the assessment of Psychological journals by CAPES to update the Qualis database. For this research, Psychology scientific editors (38 questionnaires were applied by e-mail) were consulted, also 5 librarians who work with scientific journals assessment (semi-structured interviews) and 8 members who acted as referees in the CAPES/ANPEPP Commission (open questions were sent by e-mail). The results are shown through 3 analysis: general evaluation of the Qualis process (including the Assessment Committee constitution), evaluation criteria used in the process and the effect of the evaluation on the scientific community (changes on the editing scene included). Some important points emerged: disagreement among different actors about the suitability of this evaluation model; the recognition of the improvement of scientific journals, mainly toward normalization and diffusion; the verification that the model does not point the quality of the journal, i.e., the content of the scientific articles published in the journal; the disagreement with the criteria used, seemed necessary and useful but needed to be discussed and cleared between the scientific community. Despite these points, the scientific journals evaluation still is the main method to assure quality for Psychology publications

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Mozambique holds a potential for tourism development, especially for nature tourism, due to the existence of conservation areas around the country. The Maputo Special Reserve (MES) is considered as one of the most important conservation area and has benefited from investment in order to incruse the development of tourism in the region. Currently the number of visitors to MES has grown substantially with the intention to develop recreational activities related to ecotourism. Now the challenge lies in the way of optimizing opportunities for tourism development in order to achieve economic benefitis reduction the lead to poverty, without degrading the environment. Ecotourism face the demands and environmental discussions has been assumed as an alternative to the tourist market focused on protected areas, as it is believed that this segment is able to reconcile tourism development and simultaneously improve the conservation of the natural environment and still ensure the recovery of local communities and promoting their welfare. This study aims to analyze, from the perception of the local community, social and environmental contribution of ecotourism in Maputo Special Reserve, Mozambique. The research sought to investigate the relationship between ecotourism development in the region and generate benefits for the socio-environmental communities for residents. To achieve the objective, was chosen a critical analysis about the generation of socio-environmental benefits versus ecotourism in which we opted for a qualitative and quantitative approach seeking to establish the degree of agreement and disagreement about the benefits generated by ecotourism through interviews with community members

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This thesis deals with the tectonic-stratigraphic evolution of the Transitional Sequence in the Sergipe Sub-basin (the southern segment of the Sergipe-Alagoas Basin, Northeast Brazil), deposited in the time interval of the upper Alagoas/Aptian stage. Sequence boundaries and higher order internal sequences were identified, as well as the structures that affect or control its deposition. This integrated approach aimed to characterize the geodynamic setting and processes active during deposition of the Transitional Sequence, and its relations with the evolutionary tectonic stages recognized in the East Brazilian Margin basins. This subject addresses more general questions discussed in the literature, regarding the evolution from the Rift to the Drift stages, the expression and significance of the breakup unconformity, the relationships between sedimentation and tectonics at extensional settings, as well as the control on subsidence processes during this time interval. The tectonic-stratigraphic analysis of the Transitional Sequence was based on seismic sections and well logs, distributed along the Sergipe Sub-basin (SBSE). Geoseismic sections and seismic facies analysis, stratigraphic profiles and sections, were compiled through the main structural blocks of this sub-basin. These products support the depositional and tectonic-stratigraphic evolutionary models built for this sequence. The structural analysis highlighted similarities in deformation styles and kinematics during deposition of the Rift and Transitional sequences, pointing to continuing lithospheric extensional processes along a NW trend (X strain axis) until the end of deposition of the latter sequence was finished by the end of late Aptian. The late stage of extension/rifting was marked by (i) continuous (or as pulses) fault activity along the basin, controling subsidence and creation of depositional space, thereby characterizing upper crustal thinning and (ii) sagstyle deposition of the Transitional Sequence at a larger scale, reflecting the ductile stretching and thinnning of lower and sub crustal layers combined with an increasing importance of the thermal subsidence regime. Besides the late increments of rift tectonics, the Transitional Sequence is also affected by reactivation of the border faults of SBSE, during and after deposition of the Riachuelo Formation (lower section of the Transgressive Marine Sequence, of Albian age). It is possible that this reactivation reflects (through stress propagation along the newlycreated continental margin) the rifting processes still active further north, between the Alagoas Sub-basin and the Pernambuco-Paraíba Basin. The evaporitic beds of the Transitional Sequence contributed to the development of post-rift structures related to halokinesis and the continental margin collapse, affecting strata of the overlying marine sequences during the Middle Albian to the Maastrichtian, or even the Paleogene time interval. The stratigraphic analysis evidenced 5 depositional sequences of higher order, whose vertical succession indicates an upward increase of the base level, marked by deposition of continental siliciclastic systems overlain by lagunar-evaporitic and restricted marine systems, indicating that the Transitional Sequence was deposited during relative increase of the eustatic sea level. At a 2nd order cycle, the Transitional Sequence may represent the initial deposition of a Transgressive Systems Tract, whose passage to a Marine Transgressive Sequence would also be marked by the drowning of the depositional systems. At a 3rd order cycle, the sequence boundary corresponds to a local unconformity that laterally grades to a widespread correlative conformity. This boundary surface corresponds to a breakup unconformity , being equivalent to the Pre-Albian Unconformity at the SBSE and contrasting with the outstanding Pre-upper Alagoas Unconformity at the base of the Transitional Sequence; the latter is alternatively referred, in the literature, as the breakup unconformity. This Thesis supports the Pre-Albian Unconformity as marker of a major change in the (Rift-Drift) depositional and tectonic setting at SBSE, with equivalent but also diachronous boundary surfaces in other basins of the Atlantic margin. The Pre-upper Alagoas Unconformity developed due to astenosphere uplift (heating under high lithospheric extension rates) and post-dates the last major fault pulse and subsequent extensive block erosion. Later on, the number and net slip of active faults significantly decrease. At deep to ultra deep water basin segments, seaward-dipping reflectors (SDRs) are unconformably overlain by the seismic horizons correlated to the Transitional Sequence. The SDRs volcanic rocks overly (at least in part) continental crust and are tentatively ascribed to melting by adiabatic decompression of the rising astenospheric mantle. Even though being a major feature of SBSE (and possibly of other basins), the Pre-upper Alagoas Unconformity do not correspond to the end of lithospheric extension processes and beginning of seafloor spreading, as shown by the crustal-scale extensional structures that post-date the Transitional Sequence. Based on this whole context, deposition of the Transitional Sequence is better placed at a late interval of the Rift Stage, with the advance of an epicontinental sea over a crustal segment still undergoing extension. Along this segment, sedimentation was controled by a combination of thermal and mechanical subsidence. In continuation, the creation of oceanic lithosphere led to a decline in the mechanical subsidence component, extension was transferred to the mesoceanic ridge and the newly-formed continental margin (and the corresponding Marine Sequence) began to be controlled exclusively by the thermal subsidence component. Classical concepts, multidisciplinary data and new architectural and evolutionary crustal models can be reconciled and better understood under these lines

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This thesis deals with the sedimentological/stratigraphic and structural evolution of the sedimentary rocks that occur in the NW continental border of the Potiguar Basin. These rocks are well exposed along coastal cliffs between the localities of Lagoa do Mato and Icapuí, Ceará State (NE Brazil). The sedimentological/stratigraphic study involved, at the outcrop scale, detailed facies descriptions, profile mapping of the vertical succession of different beds, and columnar sections displaying inferred lateral relationships. The approach was complemented by granulometric and petrographic analyses, including the characterization of heavy mineral assemblages. The data set allowed to recognize two kinds of lithological units, a carbonate one of very restricted occurrence at the base of the cliffs, and three younger, distinct siliciclastic units, that predominate along the cliffs, in vertical and lateral extent. The carbonate rocks were correlated to the late Cretaceous Jandaíra Formation, which is covered by the siliciclastic Barreiras Formation. The Barreiras Formation occurs in two distinct structural settings, the usual one with nondeformed, subhorizontal strata, or as tilted beds, affected by strong deformation. Two lithofacies were recognized, vertically arranged or in fault contacts. The lower facies is characterized by silty-argillaceous sandstones with low-angle cross bedding; the upper facies comprises medium to coarse grained sandstones, with conglomeratic layers. The Tibau Formation (medium to coarse-grained sandstones with argillite intercalations) occurs at the NW side of the studied area, laterally interlayered with the Barreiras Formation. Eolic sediments correlated to the Potengi Formation overly the former units, either displaying an angular unconformity, or simply an erosional contact (stratigraphic unconformity). Outstanding structural features, identified in the Barreiras Formation, led to characterize a neocenozoic stress field, which generated faults and folds and/or reactivated older structures in the subjacent late cretaceous (to paleogene, in the offshore basin) section. The structures recognized in the Barreiras Formation comprise two distinct assemblages, namely a main extensional deformation between the localities of Ponta Grossa and Redonda, and a contractional style (succeeded by oblique extensional structures) at Vila Nova. In the first case, the structural assemblage is dominated by N-S (N±20°Az) steep to gently-dipping extensional faults, displaying a domino-style or listric geometry with associated roll-over structures. This deformation pattern is explained by an E-W/WNW extension, contemporaneous with deposition of the upper facies of the Barreiras Formation, during the time interval Miocene to Pleistocene. Strong rotation of blocks and faults generated low-angle distensional faults and, locally, subvertical bedding, allowing to estimate very high strain states, with extension estimates varying between 40% up to 200%. Numerous detachment zones, parallel to bedding, help to acommodate this intense deformation. The detachment surfaces and a large number of faults display mesoscopic features analoguous to the ones of ductile shear zones, with development of S-C fabrics, shear bands, sigmoidal clasts and others, pointing to a hydroplastic deformation regime in these cases. Local occurrences of the Jandaíra limestone are controled by extensional faults that exhume the pre-Barreiras section, including an earlier event with N-S extension. Finally, WNWtrending extensional shear zones and faults are compatible with the Holocene stress field along the present continental margin. In the Vila Nova region, close to Icapuí, gentle normal folds with fold hinges shallowly pluging to SSW affect the lower facies of the Barreiras Formation, displaying an incipient dissolution cleavage associated with an extension lineation at high rake (a S>L fabric). Deposition of the upper facies siliciclastics is controlled by pull-apart graben structures, bordered by N-NE-trending sinistral-normal shear zones and faults, characterizing an structural inversion. Microstructures are compatible with tectonic deformation of the sedimentary pile, burried at shallow depths. The observed features point to high pore fluid pressures during deformation of the sediments, producing hydroplastic structures through mechanisms of granular flow. Such structures are overprinted by microfractures and microfaults (an essentially brittle regime), tracking the change to microfracturing and frictional shear mechanisms accompanying progressive dewatering and sediment lithification. Correlation of the structures observed at the surface with those present at depth was tested through geophysical data (Ground Penetrating Radar, seismics and a magnetic map). EW and NE-trending lineaments are observed in the magnetic map. The seismic sections display several examples of positive flower structures which affect the base of the cretaceous sediments; at higher stratigraphic levels, normal components/slips are compatible with the negative structural inversion characterized at the surface. Such correlations assisted in proposing a structural model compatible with the regional tectonic framework. The strong neogenepleistocene deformation is necessarily propagated in the subsurface, affecting the late cretaceous section (Açu and Jandaíra formations), wich host the hydrocarbon reservoirs in this portion of the Potiguar Basin. The proposed structural model is related to the dextral transcurrent/transform deformation along the Equatorial Margin, associated with transpressive terminations of E-W fault zones, or at their intersections with NE-trending lineaments, such as the Ponta Grossa-Fazenda Belém one (the LPGFB, itself controlled by a Brasiliano-age strike-slip shear zone). In a first step (and possibly during the late Cretaceous to Paleogene), this lineament was activated under a sinistral transpressional regime (antithetic to the main dextral deformation in the E-W zones), giving way to the folds in the lower facies of the Barreiras Formation, as well as the positive flower structures mapped through the seismic sections, at depth. This stage was succeeded (or was penecontemporaneous) by the extensional structures related to a (also sinistral) transtensional movement stage, associated to volcanism (Macau, Messejana) and thermal doming processes during the Neogene-Pleistocene time interval. This structural model has direct implications to hydrocarbon exploration and exploitation activities at this sector of the Potiguar Basin and its offshore continuation. The structure of the reservoirs at depth (Açu Formation sandstones of the post-rift section) may be controlled (or at least, strongly influenced) by the deformation geometry and kinematics characterized at the surface. In addition, the deformation event recognized in the Barreiras Formation has an age close to the one postulated for the oil maturation and migration in the basin, between the Oligocene to the Miocene. In this way, the described structural cenario represents a valid model to understand the conditions of hydrocarbon transport and acummulation through space openings, trap formation and destruction. This model is potentially applicable to the NW region of the Potiguar Basin and other sectors with a similar structural setting, along the brazilian Equatorial Atlantic Margin

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The segment of Carnaubais Fault located in the southeasthern portion of Guamaré Graben (Potiguar Basin) was studied. Several structures were detected and some of them strongly suggest that the last movements in Carnaubais Fault are of Neotectonic age. The study comprises an integrated interpretation of geologic, geomorphologic and geophysical data (gravimetry, magnetometry, resistivity, and self potential methods). According to the size of the studied areas, two approaches were used in this research. The first approach is of a regional nature and was conducted in an area, hereafter named Regional Area, having approximately 6,000 km2 and localized in the northern portion of Rio Grande do Norte state, around Macau city. The second approach comprises detailled studies of two small areas inside the Regional Area: the Camurupim and São Bento areas. Gravimetric and topographic data were used in the Regional Area. A separation into regional and residual components were conducted both on gravimetric and topographic data. The interpretation of the residual component of the gravimetric data allows a precise mapping of the borders of the Guamaré Graben. The regional component features of the topographic data are controlled by the pair of conjugate faults composed by the Carnaubais Fault (NE direction) and the Afonso Bezerra Fault (NW direction). On the other hand, the residual component of the topographic data shows that river valleis of NW direction are sharply interrupted where they intersect Carnaubais Fault. This fact is interpreted as an evidency that the last significant moviments occured in the Carnaubais Fault. Geologic, geomorphologic and geophysical data (magnetometry, resistivity, and self potential methods) were used in the Camurupim Area. The geologic mapping allows to identify five lithophacies unities. The first two unities (from base to top) were interpreted as composing a marine (or transitional) depositional sequency while the other were interpreted is composing a continental depositional sequence. The two sequences are clearly separated of an erosional discordance. The unities grouped in the marine sequence are composed by calcarenites (Unity A) and mudstones (Unity B). Unity A was deposited in a shalow plataform while Unity B, in a tidal flat. The unities grouped in the continental sequence are composed of conglomerate (Unity C) and sandstones (Unities D and E). Unities C and D are fluvial deposits while unity E is an eolian deposit. Unities A and B can be stratigraphycally correlated with Guamaré Formation. Unities C and D present three possible correlations. They may be correlated with Tibau Formation; or with Barreiras Formation; or with a clastic sediment deposit, commonly found in some rivers of Rio Grande do Norte state, and statigraphycally positioned above Barreiras Formation. Based on the decrease of the grain sizes from base to top both on unities C and D, it is proposed that these unities are correlated with the clastic sediment above mentioned. In this case, these unities would have, at least, Pleistocenic age. Finally, it is proposed that Unity E represent an eolian deposit that sufferred recent changes (at least in the Quaternary). The integrated interpretation of hydrographic, morphologic and geophysical data from Camurupim Area shows that Carnaubais Fault is locally composed by a system of several paralel subvertical faults. The fault presenting the larger vertical slip controls the valley of Camurupim river and separates the area in two blocks; in the nothern block the top of the Jandaira limestone is deeper than in the southern block. In addition, at least one of the faults in the northern block is cutting the whole sedimentary section. Because unities C , D, and/or E may be of Quaternary age, tectonic moviments possibly occured in Carnaubais Fault during this period. Detailled geologic mapping were conducted in beachrocks found in São Bento Area. This area is located at the intersection of the coast line with the Carnaubais Fault. The detected structures in the beachrocks are very similar to those caused by fragile deformations. The structures mapped in the beachrocks are consistent with a stress field with maximun compressional stress in E-W direction and extensional stress in the N-S direction. Since the Carnaubais Fault has a NE direction, it is optimally positioned to suffer tectonic movements under the action of such stress field. In addition, the shape of the coastal line appear to be controlled by the Carnaubais Fault. Furthemore, the observed structures in Camurupim Área are consistent with this stress field. These facts are interpreted as evidences that Carnaubais Fault and beachrocks suffered coupled tectonic movements. These moviments are of Neotectonic age because the beachrocks present ages less than 16,000 years

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A complex depositional history, related to Atlantic rifting, demonstrates the geological evolution during the late Jurassic and early Neocomian periods in the Araripe Basin NE Brazil. Based on outcrop, seismic and remote sensing data, a new model of the tectono-stratigraphic evolution of the section that covers the stages Dom João, Rio da Serra and Aratu (Brejo Santo, Missão Velha and Abaiara formations) is presented in this paper. In the stratigraphic section studied, ten sedimentary facies genetically linked to nine architectural elements were described, representing depositional systems associated with fluvial, aeolian and deltaic environments. Based on the relationship between the rates of creation of accommodation space and sediment influx (A / S) it was possible to associate these depositional systems with High and Low accommodation system tracks. These system tracks represent two tectono-sequences, separated by regional unconformities. The Tectono-sequence I, which includes lithotypes from the Brejo Santo Formation and is related to the pre-rift stage, is bounded at the base by the Paleozoic unconformity. This unit represents only a High Accommodation System Track, composed by a succession of pelitic levels interbedded with sandstones and limestones, from a large fluvial floodplain origin, developed under arid climatic conditions. The Tectono-sequence II, separated from the underlying unit by an erosional unconformity, is related to the rift stage, and is composed by the Missão Velha and Abaiara Formation lithotypes. Changes in depositional style that reflect variations in the A / S ratio, and the presence of hydroplastic deformation bands, make it possible to divide this tectonosequence into two internal sequences. Sequence IIA, which includes the lower portion of the Missão Velha Formation and sequence IIB, is composed by the upper section of the Missão Velha and Abaiara Formations The Sequence IIA below, composed only by the Low Accommodation System Track, includes crossbedding sandstones interbedded with massive mudstones, which are interpreted as deposits of sandy gravel beds wandering rivers. Sequence IIB, above, is more complex, showing a basal Low Accommodation System Track and a High Accommodation System Track at the top, separated by an expansion surface. The lower System Track, related to the upper portion of the Missão Velha Formation, is composed by a series of amalgamated channels, separated by erosion surfaces, interpreted as deposits of a belt of braided channels. The High Accommodation System Track, correlated with the Abaiara Unit, is marked by a significant increase in the A / S, resulting in the progradation of a system of braided river deltas with aeolic influence. Regarding tectonic evolution, the stratigraphic study indicates that the Tectonosequence Rift in the Araripe basin was developed in two phases: first characterized by a beginning of rifting, related to Sequence IIA, followed by a phase of syndepositional deformation, represented by sequence IIB. The first phase was not influenced by the development of large faults, but was influenced by a sharp and continuous decrease of accommodation space that permitted a change in depositional patterns, establishing a new depositional architecture. In turn, the stage of syndepositional deformation allowed for the generation of enough accommodation space for the preservation of fluvial-lacustrine deposits and conditioned the progradation of a braided river-dominated delta system.

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The Palestina Graben is one of the NE-trending asymmetric grabens of the Araripe Basin. This basin rests on the precambrian terrains of the Transversal Zone, Borborema Province, immediately to the south of the Patos Lineament. It is part of the Interior Basins province of Northeastern Brazil, being related to the fragmentation of the Gondwana supercontinent and the opening of the South Atlantic ocean. The Palestina Graben trends NE-SW and presents an asymmetric geometry, controled by the NW extensional eocretaceous strain. The graben borders display distinct geometries. The SE border is a flexural margin, characterized by the non conformity of the eopaleozoic Mauriti Formation (the oldest unit of the basin) overlying the crystalline basement, but also affected by normal faults with small displacements. On the opposite, the NW border is continuous and rectilinear, being marked by normal faults with major displacements, that control the general tilting of the layers to the NW. In this sense, the Mauriti Formation is overlain by the Brejo Santo, Missão Velha (which also occurs in the Brejo Santo-Mauriti horst, to the NW of the fault border) and Abaiara formations, the latter restricted to the graben. The interpretation of available gravity data and a seismic line indicates that the main fault has a variable dip slip component, defining two deeper portions within the graben, in which the sedimentary column can reach thicknesses of up to 2 km. Regarding to the stratigraphy of Araripe Basin in the study area, the sedimentary package includes three distinct tectonosequences. The Paleozoic Syneclisis Tectonosequence is composed by the Mauriti Formation, deposited by a braided fluvial system. The Jurassic Tectonosequence, whose tectonic setting is still debatable (initial stage of the Neocomian rift, or a pre-rift syneclisis ?), is represented by the Brejo Santo Formation, originated in a distal floodplain related to ephemeral drainages. The Rift Tectonosequence, of neocomian age, includes the Missão Velha Formation, whose lower section is related to a braided to meandering fluvial system, outlining the Rift Initiation Tectonic Systems Tract. The upper section of the Missão Velha Formation is separated from the latter by a major unconformity. This interval was originated by a braided fluvial system, overlain by the Abaiara Formation, a deltaic system fed by a meandering fluvial system. Both sections correspond to the Rift Climax Tectonic Systems Tract. In the area, NE-trending normal to oblique faults are associated with NW transfer faults, while ENE to E-W faults display dominant strike slip kinematics. Both NE and E-W fault sets exhibit clear heritage from the basement structures (in particular, shear zones), which must have been reactivated during the eocretaceous rifting. Faults with EW trends display a dominant sinistral shear sense, commonly found along reactivated segments of the Patos Lineament and satellyte structures. Usually subordinate, dextral directional movements, occur in faults striking NNW to NE. Within this framework bearing to the Palestina Graben, classical models with orthogonal extension or pull-apart style deserve some caution in their application. The Palestina Graben is not limited, in its extremeties, by E-W transcurrent zones (as it should be in the case of the pull-apart geometry), suggesting a model close to the classic style of orthogonal opening. At the same time, others, adjacent depocenters (like the Abaiara-Jenipapeiro semi-graben) display a transtensional style. The control by the basement structures explains such differences

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The aim of this study is to highlight the cultural identities of Spanish undergraduate students from Instituto Federal de Educação, Ciência e Tecnologia – IFRN, in integration with Universidade Aberta do Brasil – UAB, in the distance modality, built from utterances produced by them in a forum discussion online. For this, we chose to analyze the thematic forum “Using fragments of the internet is an ethical act?” generated in the first semester of 2011, linked to the Reading and Writing course. The interest of this researcher to highlight the cultural identities of these subjects, in the Virtual Learning Environment, emerged from the contact with this reality, in which it was found that the statements constructed by students were rich in positions, meanings and interactions. By producing their speeches, such subjects nurture a reflection on how we can establish meaning in the interaction created in online teaching as well as on the construction of cultural identities of the subject within that virtual space. The way students participate in the discussion forum represents learning experiences that lead to the construction of cultural identities, which determine the trajectory of the subjects, which makes the identity an ongoing process. Our theoretical reference follows the interdisciplinary approach of Applied Linguistics and is based on the socio-historical model of language, with language construed as a social practice. This study also established an interface with cultural studies, as it uses the concept of cultural identity in postmodernity. Analysis of the utterances lead to plurality, with a multiplicity of identities, as evidenced from the positioning of the subjects, some focused on the agreement, others on the disagreement, or even on the boldness. It was found also in the investigative path that these identities can be constructed and reconstructed if they are immersed in another set of historically determined social practices.