Alterações na evocação de uma memória aversiva ao liongo do ciclo estral de ratas: influências da transmissão gabaérgica na amígdala

GABAergic neurotransmission has been implicated in many aspects of learning and memory, as well as mood and anxiety disorders. The amygdala has been one of the major focuses in this area, given its essential role in modulating emotionally relevant memories. However, studies with male subjects are still predominant in the field. Here we investigated the consequences for an aversive memory of enhancing or decreasing GABAergic transmission in the basolateral nucleus of the amygdala (BLA). Wistar female rats were trained in the plus-maze discriminative avoidance task, in which they had to learn to avoid one of the enclosed arms where an aversive stimulus consisting of a bright light and a loud noise was given (day 1). Fifteen minutes before the test session (day 2) animals received 0,2 μL infusions of either saline solution, the GABAergic agonist muscimol (0,05 mg/ml), or the GABAergic antagonist bicuculine (0,025 mg/ml) bilaterally intra-BLA. On the test day, females in proestrous or estrous presented adequate retrieval and did not extinguish the task, while females in metestrous or diestrous presented impaired retrieval. In the first group, muscimol infusion impaired retrieval and bicuculline had no effect, suggesting naturally low levels of GABAergic transmission in the BLA of proestrous and estrous females. In the second group, muscimol infusion had no effect and bicuculline reversed retrieval impairment, suggesting naturally high levels of GABAergic transmission in the BLA of metestrous and diestous females. Additionally, proestrous and estrous females presented higher anxiety levels compared to metestrous and diestrous females, which could explain better performance of this group. On the other hand, BLA GABAergic system did not interfere with the innate fear response because drug infusions had no effect in anxiety. Thus, retrieval alterations caused by the GABAergic drugs were probably related specifically to memory processes

Investigação da influência do cochilo na aprendizagem escolar

There is a known positive effect of nocturnal sleep for brain plasticity and the consolidation of declarative and procedural memories, as well as for the facilitation of insight in problem solving. However, a possible pro-mnemonic effect of daytime naps after learning is yet to be properly characterized. The goal of this project was to evaluate the influence of daytime naps on learning among elementary and middleschool students, measuring the one-day (acute), and semester-long (chronic) effects of post-learning naps on performance. In the Acute Day-Nap condition, the elementary students were exposed to a class and then randomly divided into three groups: Nap (N), Game-based English Class (GBEC) and Traditional English Class (TEC). There were 2 multiple-choice follow-up tests to evaluate students performance in the short and long runs. In the short run, the N group outperformed the other two groups; and such tendency was maintained in the long run. In the chronic condition, the middle-school students were randomly separated into two groups: Nap (N) and Class (C) and were observed during one academic term. The N group had increased school performance in relation to the C group. In the statistical analyses, independent t-tests were applied considering the scores significant when p<0,05, expressed in terms of average ± average standard error. Results can be interpreted as an indication that a single daytime nap opportunity is not enough to ensure learning benefits. Therefore, more research is needed in order to advocate in favor of a daytime nap as a pedagogical means of promoting enhanced school performance

Efeitos de diferentes tipos estressores sobre a memória e aprendizagem de ratas

The exposure to stressors produces physiological changes of the organism in order to adapt the individual to the environment. Depending on the type, intensity and duration, stress can affect some cognitive functions, particularly processes of learning and memory. Several studies have also proposed that some level of anxiety would be necessary for memory formation. In this context, memories of previously aversive experiences may determine the manner and intensity with which are expressed fear responses, which explains the great interest in analyzing both anxiety and memory in animals. In addition, males and females demonstrate different reactions in relation to stressful stimuli, showing different levels of anxiety and differences in processing of the acquisition, retention and recall of information. Based on this information, the present study aimed to verify the effect of stress on learning, memory and anxiety behavioral parameters in rats exposed at different types of stressors of long duration (seven consecutive days): restraint (4h/day), overcrowding (18h/day) and social isolation (18h/day) in the different phases of the estrous cycle. Our results showed that the stress induced by restraint and social isolation did not cause changes in the acquisition process, but impaired the recall of memory in rats. Furthermore, it is suggested a protective effect of sex hormones on retrieval of aversive memory, since female rats in proestrus or estrus phase, characterized by high estrogen concentrations, showed no aversive memory deficits. Furthermore, despite the increased plasma levels of corticosterone observed in female rats subjected to restraint stress and social isolation, anxiety levels were unaltered, compared to those various stress conditions. Animal models based on psychological and social stress have been extensively discussed in the literature. Correlate behavioral responses, physiological and psychological have contributed in increasing the understanding of stress-induced psychophysiological disorders

Efeito do alerta e valência emocional nos componentes de lembrança e familiaridade da memória episódica

The episodic memory system allows us to retrieve information about events, including its contextual aspects. It has been suggested that episodic memory is composed by two independent components: recollection and familiarity. Recollection is related to the vivid e detailed retrieval of item and contextual information, while familiarity is the capability to recognize items previously seen as familiars. Despite the fact that emotion is one of the most influent process on memory, only a few studies have investigated its effect on recollection and familiarity. Another limitation of studies about the effect of emotion on memory is that the majority of them have not adequately considered the differential effects of arousal and positive/negative valence. The main purpose of the current work is to investigate the independent effect of emotional valence and arousal on recollection and familiarity, as well as to test some hypothesis that have been suggested about the effect of emotion on episodic memory. The participants of the research performed a recognition task for three lists of emotional pictures: high arousal negative, high arousal positive and low arousal positive. At the test session, participants also rated the confidence level of their responses. The confidence ratings were used to plot ROC curves and estimate the contributions of recollection and familiarity of recognition performance. As the main results, we found that negative valence enhanced the component of recollection without any effect on familiarity or recognition accuracy. Arousal did not affect recognition performance or their components, but high arousal was associated with a higher proportion of false memories. This work highlight the importance of to consider both the emotional dimensions and episodic memory components in the study of emotion effect on episodic memory, since they interact in complex and independent way

Investigação da memória autobiográfica em idosos com demência de Alzheimer nas fases leve e moderada

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Cartografia de uma intervenção comunitária para prevenção de DST/HIV/AIDS

Community-based interventions have been presented as a proposal of operationalization of the concept of vulnerability to STD/Aids prevention. This study aimed to analyze the Community intervention developed through the project Strengthening of Community action networks for STD/Aids prevention: know and intervenein, at Mãe Luiza neighborhood, in the city of Natal, State of Rio Grande do Norte, Brazil. The study was conducted in the same location where intervention occurs and took as time reference the first 30 months of construction and deployment process, from April 2010 until December 2012. This is research with qualitative approach, participatory character, developed from the immersion of the researcher in the field, being this community intervention itself. In this perspective, the study approximates to the Cartographic method in which the researcher-researched is engendered in the acts and effects research. The data-generating sources were the memories of the researcher from the field notes, written narratives of subjects involved in the intervention and documents pertaining to the project. In the methodological path of cartography, the image of the rhizome by Deleuze and Guattari (1995) has accompanied the immersion in the field given the nature of research-intervention which approach to the concept of object-Rhizome. The presentation of results was composed for the attempted rhizomatic and a hypertext representation, based on the descriptive narrative taken from the documentary analysis and the multi-faceted narratives with the voices, the looks and the affections narrated by the subject involved, respectively. On the path taken, three lanes were drawn as synthesis of learning produced by experience-that can contribute to understanding the process under study, in his singular character, and reflections on other experiences of community intervention: track 1- Community intervention as active-reflective space and a cause; track 2 Inclusion as power and challenge of community involvement; track 3 Sustainability as A challenge of Community intervention. The study indicates that community intervention is presented as a potential producer of health as also produces practical and creative skills, subjects and inventive in the daily life of the community with a view to reinventing knowledge and practices for the prevention of STD/HIV/Aids

Lembranças de alunos, imagens de professores: narrativas e diálogos sobre a formação médica

Se trata de una incursión histórica por el pensamiento y por la enseñanza médica, discutiéndose la formación médica de manera contextualizada, con el objetivo de comprenderla para interpretarla a través del recuerdo que haya sido fijado por los alumnos. Se dará un enfoque a la mediación pedagógica de esa formación, intentando proporcionar el diálogo entre la historia social de la Medicina y los recuerdos de alumnos, ubicándolas en un contexto histórico-social y cultural, al mismo tiempo en que se ha buscado sujetar las imágenes de los profesores que hayan dejado huellas significativas en la vida de los alumnos, en cuestiones profesionales, sociales y culturales. Se configura, asimismo, una memoria de la formación médica de la Faculdade de Medicina da Universidade Federal do Rio Grande do Norte (UFRN), desde su creación en el 1955, como Faculdade de Medicina de Natal, hasta el 1963, como Faculdade de Medicina da UFRN. Los recuerdos han sido recolectados por medio de entrevistas temáticas con alumnos ya formados de las tres primeras turmas concluyentes, de los años del 1961, 1962 y 1963, de la referida Facultad y fueron interpretadas utilizándose la cartografía como técnica que envuelve la construcción de cuadros interpretativos, teniendo como unidad de análisis las palabras representativas de los elementos constituyentes de la mediación pedagógica, sacadas de las narrativas de los sujetos, que cargan también las imágenes de los profesores que han compuesto dicho diálogo por sus contribuciones para la existencia del saber y hacer de la educación médica en Natal/RN. Aún se comprende que esa Facultad fue creada en un momento histórico-social y cultural en que Brasil y el mundo todavía intentaban encontrar nuevos caminos, después de turbulencias causadas por la Segunda Guerra Mundial, y la intelectualidad natalense visualizaba el encaje de la ciudad en los parámetros de la modernidad. El currículum implantado era técnico/racional, pero al ser interpretado por la acción, a través de la reconstrucción de los recuerdos de los alumnos, en los vestigios de la mediación pedagógica de la formación médica y en las imágenes de los profesores todavía vivas en sus memorias, se vuelve posible entender que a esos alumnos ha sido enseñado: un saber relacional que permitía el diálogo, la transmisión de experiencia y el compromiso médico con vista a un atendimiento a la populación en primer lugar, siguiéndole el sentimiento que fomentaba deseos de ayuda al próximo, siendo los propios profesores el ejemplo, conformándose, así, con un saber contextual, agregado a una participación política y de responsabilidad ética para con la sociedad

Histerese térmica de sistemas magnéticos nanoestruturados

We report a theoretical investigation of thermal hysteresis in magnetic nanoelements. Thermal hysteresis originates in the existence of meta-stable states in temperature intervals which may be tuned by small values of the external magnetic field, and are controlled by the systems geometric dimensions as well as the composition. Two systems have been investigated. The first system is a trilayer consisting of one antiferromagnetic MnF2 film, exchange coupled with two Fe lms. At low temperatures the ferromagnetic layers are oriented in opposite directions. By heating in the presence of an external magnetic field, the Zeeman energy induces a gradual orientation of the ferromagnets with the external field and the nucleation of spin- op-like states in the antiferromagnetic layer, leading eventually, in temperatures close to the Neel temperature, to full alignment of the ferromagnetic films and the formation of frustrated exchange bonds in the center of the antiferromagnetic layer. By cooling down to low temperatures, the system follows a different sequence of states, due to the anisotropy barriers of both materials. The width of the thermal hysteresis loop depends on the thicknesses of the FM and AFM layers as well as on the strength of the external field. The second system consists in Fe and Permalloy ferromagnetic nanoelements exchange coupled to a NiO uncompensated substrate. In this case the thermal hysteresis originates in the modifications of the intrinsic magnetic

Sobre pedras, entre rios: modernização do espaço urbano de Caicó/RN (1950/1960)

thèse de maîtrise, qui a été idealizée et exécutée à partir de la réunion et les relations dialogiques établies entre la géographie et l'histoire, et l'espace et le temps, a considéré l'environnement urbain comme le thème général et, comme la référence empirique, l'espace urbain de Caicó, incrusté dans les terres semi-arides du Sertão do Seridó Potiguar, plus précisément à la mi-sud de l'État du Rio Grande do Norte. Dans cet espace, à travers de recherche des fragments de mémoires acquis de diverses sources historiques, on a tenté de faire des investigations sur les transformations urbaines qui ont eu lieu dans la ville au cours des années 50 et 60 du XXe siècle. Ces transformations, dans l espace urbain de Caicó à un moment du pic de l'activité de développement de coton, reflétaient et conditionnaient les propres projets de modernization urbaine qui représentants des élites locales eurent conçu avec l'objectif de la construction d une ville idéal dans les regions isolées du Seridó: moderne, civilisé, progressive et capitale régionale du Seridó. Pour cette construction, les nouveaux équipements et services urbains ont passé du plan imaginaire à l espace réel, installés dans plusieurs quartiers de la ville en transformant le paysage urbain. Face à cette situation, cinémas, magasins, station de radio, énergie électrique, institutions de l'éducation, téléphonie, maison de soins infirmiers, usine de bénéficiement de coton, banques, politiques urbaines, hygiéniques et sanitaires, modes de comportement, sociabilités urbaines distincttes, parmi d'autres éléments géographiques se sont institués à travers la réalisation de certains idéaux de progrès social et dans un esprit de modernité urbaine, dans de nouveaux espaces et pratiques inventés, tramés et éprouvés sur les rochers et entre le cours d eau au milieu d'un quotidien urbain marqué par ruptures et permanence de certaines coutumes et habitudes antiques et de certains paysages et environnement ridé

Nostalgia do espaço e do tempo: uma leitura da obra memorialística de Câmara Cascudo

This dissertation addresses the work of the memoirs of the potiguar writer Luís da Câmara Cascudo (1898 - 1986) from an integrated reading of four works that comprise: O Tempo e Eu (1968), Pequeno Manual do Doente Aprendiz (1969), Na Ronda do Tempo (1971) and Ontem (1972). Produced under the contingency of the modern movement and urban reform, memories Cascudo evoke the old landscapes of old, populated by those who belonged to the old romantic and provincial Natal that no longer exists, but which still survives in the idealized memory author and that is (re)constructed by him from a written permeated with touches of imagination and a sense of nostalgia. Seeking to analyze how is the process of building memoirist of Cascudo, as well as reflect on the role that memory plays in the (re)construction of a time and a lost space, we used the studies of Maurice Halbwachs (2006) and Ecléa Bosi (1994). Within this theoretical framework, we seek, above all, to understand not only how the lived experiences of Cascudo will work in this matter of his memory, but also as this will guide a writing that touches on the history and social frameworks of the past

Trajetória de vida dos pescadores vítimas de lesão medular por mergulho: experiências, representações sociais e estresse

Spinal cord injury causes permanent disabling manifestations, affecting the anatomic integrity, bodily changes and functional limitations related to the disability state. It was aimed to analyze the social representation, stress level and experiences of fishermen victims of spinal cord injury caused by diving accident in the Northern beaches of Brazil. It is a descriptive - exploratory study with quantitative, qualitative and representational data developed i n fishermen’s villages in nine beaches of Northern shore/RN, between October 2013 to August 2014, after the approval of the Ethics Committee in Research of the Universidade Federal do Rio Grande do Norte, under the number 431.891/2013, CAAE 20818913.0.0000 .5537. The sample was composed by 44 fishermen with spinal cord injury, defined from inclusion and exclusion criteria of the participants. It was used as instrument to collect the data a semi structured interview. Quantitative data was analyzed by descrip tive statistics, showing the data through table, boxes and graphics by Microsoft Excel. Data from interviews were submitted to the software called Analyse Lexicale par Contexte d’un Ensemble de Segments de Texte (ALCESTE) using the analysis of the Social R epresentation Theory and Center Core Theory. It is shown the outcomes of the research through four articles, following the normative recommendations of the journals. Participants of the study were all male, age mean 49,6 years, elementary school (68,2%), m arried (77,3%); paraplegia sequel (50,0%). Most of them showed stress (75,0%), almost in the exhaustion stage (33,3%), prevalent insomnia symptoms (95,5%) in the last hours; hypertension (97,7%) in the last week and sexual troubles (95,5%) in the last mont h). Decompressive illness caused spinal cord injury (57,1%), occurred prevalently in low summer (75,0%), northern shore (96,4%), having as main consequences the paresthesia and pain in the upper and lower limbs (67,9%), followed by death (25,0%). Interview analysis under the understanding of Social Representation of spinal cord injury allowed the appearance of seven categories: Treatment: limitation and expectative; Spinal Cord injury: before and after; Retirement: reality yet to come; Disability: dependenc y, incapacity, vulnerability; Overcoming and autonomy; Self feelings: physics losses and new start; Life and labor: impediments, plans and changes. The center core of the representation is found in the first category by the expectative and limitation on th e treatment, meanwhile the outskirt elements are in seventh and third categories. Physics limitation for fishing activities and retirement expectative is the most outstanding of the structure. Social representation concerning spinal cord injury is found in a transaction moment between before and after with the prevented fishing activity, coping of the situation with the potential remaining. The anchoring is established in the desire for changes related to the improvements of life and health conditions exper ienced day by day through faith. This study finishes pointing out the range of the objectives, which topic is relevant for public health of fishermen. It is suggested prevention measures, promotion and health recovery of fishermen, besides safe, healthy an d worthy conditions as a compromise of social and health politics.

Estudo da densidade de corrente crítica para reversão da magnetização de nanoelementos ferromagnéticos

The discovery that a spin-polarized current is capable of exerting a torque in a ferromagnetic material, through spin transfer, might provide the development of new technological devices that store information via the direction of magnetization. The reduction of current density to revert the magnetization is a primary issue to potential applications on non volatile random access memories (MRAM). We report a theorical study of the dipolar and shape effects on the critical current density for reversal of magnetization, via spin transfer torque (STT), on ferromagnetic nanoelements. The nanostructured system consists on a reference layer, in which the current will be spin-polarized, and a free layer of magnetization reversal. We observed considerable changes on the critical current density as a function of the element’s reversion layer thickness (t = 1.0 nm, 1.5 nm, 2.0 nm e 2.5 nm) and geometry (circular and elliptical), the material kind of the system free layer (Iron and Permalloy) and according to the orientation of the magnetization and the spin polarization with the major axis. We show that the critical current density may be reduced about 50% by reducing the Fe free layer thickness and around 75% when we change the saturation magnetization of circular nanoelements with 2.5 nm of thickness. We still observed a reduction as much as 90% on the current density of reversion for thin nanoelements magnetized along the minor axis direction, using in-plane spin polarization parallel to the magnetization.

Os fios da memória: presença afro-brasileira em Acari no tempo do algodão

La historia de la expansión colonial en los sertónes del Seridó del siglo XVIII y el asentamiento de los primeros pobladores alrededor de las haciendas de ganado y más tarde de la cultura de algodón, oculto la presencia afrodescendiente que ya regia esa vasta región. Por otro lado, la esclavitud se observaba como un fenómeno de segunda prioridad y leve, por el hecho de tener un número de esclavos muy reducido en relación al litoral azucarero; sin embargo no se puede minimizar las marcas que dejaron más de tres siglos de dominación colonial, pues la violencia simbólica en su descripción aun existe. Este trabajo tiene como objetivo reflexionar sobre las causas y consecuencias de la extinción precoz de la presencia afro-brasileña y de la invisibilidad de los núcleos familiares en el municipio de Acari. A través de las memorias de las familias Nunes, Inácio y Pereira, antiguos moradores del Saco de los Pereira y de las familias Pedros, Paula, Higinos y Félix outroras moradores de las haciendas de la región, pretendemos reflexionar sobre las actividades de sobrevivencia, las relaciones de trabajo, la propiedad de la tierra y los robos ocurridos en los siglos XIX – XX, así como mostrar la importancia de las tradiciones familiares en la elaboración de los discursos sobre el pasado y de las variadas identidades. La metodología utilizada durante la investigación, mantuvo como foco las entrevistas que contemplan historias de la vida y las memorias de nuestros interlocutores, en particular los afrodescendientes. Los relatos colocan una luz sobre las vivencias en el período algodonero, los oficios realizados en las haciendas (vaquero, bordado, culinaria, losa) donde se muestra la importancia de las familias negras para entender el escenario Acarienses. También fotos y documentos cartoriáles que ayudaron a componer las historias de vida. El estudio revela la presencia de muchas familias negras vinculadas a las haciendas, demostrando que existe otra versión de la historia local, teniendo como protagonistas aquellos cuya memoria fue silenciada y quedando así marcados por el estigma de la esclavitud.

Território para viver: dinâmicas territoriais da comunidade quilombola de Acauã, Poço Branco, Rio Grande do Norte

In the late 1980s, the quilombola (or maroon) communities emerged on the Brazilian public scene. They established themselves as new collective subjects and ethnic groups, in a historical moment of sensitive political changes in several social conflicts and struggles, both in Brazil and in Latin America. Because of their socio-cultural and historical singularities, these communities have self-identified in the same collective expression and have organized in search of recognition and respect for their rights. Quilombo communities and other self-labeled as "traditional communities" seek to reaffirm their differences in opposition to a conscious colonizer cultural project and re-signify their memories and traditions, that serve as reference in the construction of alternative production projects and community organization. One of the distinguishing characteristics of this quilombola political emergence process is the territorial nature of the struggles, manifested in at least two directions: on the one hand, the struggle for legal and formal recognition of a given space, i.e., the regularization and titling of occupied territories, considering that the Brazilian Constitution of 1988 recognizes the right of these communities to the final possession of the traditional lands. On the other hand, the struggle for recognition of their territoriality in a broader sense, not necessarily restricted to the demarcated area, but as the recognition of a culture and its own way of life, that originated historically in these territories. The current accomplishments and challenges of the Brazilian quilombola communities are well exemplified by the quilombo of Acauã, in the Poço Branco municipality of Rio Grande do Norte. The last fifteen years have been marked by important changes in this community, which has gained visibility and has emerged as a new political player. Acauã identified itself as quilombola community in 2004, the same year that it formalized its political structure, through the creation of the Association of Residents of Quilombo Acauã (AMQA, in Portuguese). Also in 2004, it requested to the National Institute of Colonization and Land Reform (INCRA, in Portuguese) the opening of the process for regularization and titling of quilombo territory, which is at an advanced stage, but so far without definitive resolution. This study aims to understand the process of territorialization (struggle for territorial claim) played in the last fifteen years by the community of Acauã.

Mediação biográfica: propostas para a formação docente

This work aims at studying the biographical mediation taken as the progress of people in formation process who develop a biographical work on their own experiences with the help of a former (PASSEGGI, 2006, 2011). The research was carried out on a curricular component from Curso de Formação Inicial e Continuada (initial and continuous process of formation of teachers) with teachers from public schools developed by Instituto Federal de Educação do Rio Grande do Norte (IFRN/ Ipanguaçu). The target audience featured diversity of professionals and experiences of formation. The general objective studied the potentials of procedures and devices used to mediate the reflection about the necessary knowledge to teaching practice based on their own experiences (auto-biographical) and the experience from the others (hetero-biographical). The study tried to respond to the following questions: how do teachers in formation relate themselves to the knowledge from experience? What procedures and devices contribute on the teachers‟ formation on the three different dimensions of biographical mediation (initiatory, maieutic, hermeneutics)? How to provide the auto-formation and hetero-formation? The theories and methods of this work are based on studies and researches that place the person in formation in the center of investigation and formation and analyze their reflective, re-inventive and self-re-inventive capacity. (FREIRE, 1987, 1996, 2001, 2011; JOSSO, 2008, 2010, 2012; DELORY-MONBERGER, 2006, 2008, 2012; CHARLLOT, 2000; CATANI, 2001; PASSEGGI, 2008; 2010; 2011; 2012). We selected six teachers who participate entirely on the meetings of the program. They discussed on the study topics, shared narrations that integrate their formation and the themes related to the course. The empirical material is composed by the narrations of the six participants and hearing boards done by themselves at the moment of the narration sharing process. The analysis followed three steps: a) the path of the program and the procedures of biographical mediation; b) the relations former/teacher on the three dimensions of biographical mediation; c) the hearing board as a device of biographical mediation. We concluded that the procedures and devices used for biographical mediation made possible specific learnings that are sources for the practice of initial and continuous teachers‟ formation, as well as for the formation of the former-researcher about the work with autobiographical narrations. Thus, it allow the co-investment of participants into the process of auto-formation and hetero-formation.