82 resultados para Memória operacional


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Several studies have shown that there is a circadian modulation of explicit memory. This modulation can occur independently in each one of the mnemonic processes. The aim of this study was to evaluate the influence of time of training on short-term memory (STM) and long-term memory (LTM), using a recognition task. Moreover, a possible circadian modulation in retrieving was investigated when this process matched the acquisition hour (time stamp). The chronotype variable was also considered. Fifty-seven undergraduate students aging between 18 and 25 years (21,72 ± 2,14; 28 ♂) participated in this study. In the training phase (acquisition) the subjects heard a ten word list. Following this, they answered a recognition test to evaluate STM and one week later they answered a recognition test to evaluate LTM. In each chronotype, the subjects were divided in groups according to the training hour, part of them in the morning and the other in the afternoon. One week later some of the subjects in each group underwent LTM testing in the morning and others in the afternoon. When the subjects performances were analyzed together, independently of the chronotypes, a training hour effect was found in the LTM. The subjects trained in the afternoon had better performance. No time of day effect was found in the STM and in retrieving from the LTM. However, the morning types who were trained and tested in the same hour had a better performance in the LTM when compared to morning types trained and tested in different hours. This effect did not occur when the other chronotypes were analyzed. The circadian modulation seems to occur at least in two different ways. First, there is a circadian modulation in the acquisition/consolidation processes, with a better performance occuring in the afternoon. Secondly, there is a modulation in the retrieval mnemonic process, called time stamp phenomenon. This phenomenon, that occurred in the morning types, is showed for the first time in humans

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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It bet on the next generation of computers as architecture with multiple processors and/or multicore processors. In this sense there are challenges related to features interconnection, operating frequency, the area on chip, power dissipation, performance and programmability. The mechanism of interconnection and communication it was considered ideal for this type of architecture are the networks-on-chip, due its scalability, reusability and intrinsic parallelism. The networks-on-chip communication is accomplished by transmitting packets that carry data and instructions that represent requests and responses between the processing elements interconnected by the network. The transmission of packets is accomplished as in a pipeline between the routers in the network, from source to destination of the communication, even allowing simultaneous communications between pairs of different sources and destinations. From this fact, it is proposed to transform the entire infrastructure communication of network-on-chip, using the routing mechanisms, arbitration and storage, in a parallel processing system for high performance. In this proposal, the packages are formed by instructions and data that represent the applications, which are executed on routers as well as they are transmitted, using the pipeline and parallel communication transmissions. In contrast, traditional processors are not used, but only single cores that control the access to memory. An implementation of this idea is called IPNoSys (Integrated Processing NoC System), which has an own programming model and a routing algorithm that guarantees the execution of all instructions in the packets, preventing situations of deadlock, livelock and starvation. This architecture provides mechanisms for input and output, interruption and operating system support. As proof of concept was developed a programming environment and a simulator for this architecture in SystemC, which allows configuration of various parameters and to obtain several results to evaluate it

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Nowadays several electronics devices support digital videos. Some examples of these devices are cellphones, digital cameras, video cameras and digital televisions. However, raw videos present a huge amount of data, millions of bits, for their representation as the way they were captured. To store them in its primary form it would be necessary a huge amount of disk space and a huge bandwidth to allow the transmission of these data. The video compression becomes essential to make possible information storage and transmission. Motion Estimation is a technique used in the video coder that explores the temporal redundancy present in video sequences to reduce the amount of data necessary to represent the information. This work presents a hardware architecture of a motion estimation module for high resolution videos according to H.264/AVC standard. The H.264/AVC is the most advanced video coder standard, with several new features which allow it to achieve high compression rates. The architecture presented in this work was developed to provide a high data reuse. The data reuse schema adopted reduces the bandwidth required to execute motion estimation. The motion estimation is the task responsible for the largest share of the gains obtained with the H.264/AVC standard so this module is essential for final video coder performance. This work is included in Rede H.264 project which aims to develop Brazilian technology for Brazilian System of Digital Television

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The increasingly request for processing power during last years has pushed integrated circuit industry to look for ways of providing even more processing power with less heat dissipation, power consumption, and chip area. This goal has been achieved increasing the circuit clock, but since there are physical limits of this approach a new solution emerged as the multiprocessor system on chip (MPSoC). This approach demands new tools and basic software infrastructure to take advantage of the inherent parallelism of these architectures. The oil exploration industry has one of its firsts activities the project decision on exploring oil fields, those decisions are aided by reservoir simulations demanding high processing power, the MPSoC may offer greater performance if its parallelism can be well used. This work presents a proposal of a micro-kernel operating system and auxiliary libraries aimed to the STORM MPSoC platform analyzing its influence on the problem of reservoir simulation

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One of the mechanisms responsible for the anomalous diffusion is the existence of long-range temporal correlations, for example, Fractional Brownian Motion and walk models according to Elephant memory and Alzheimer profiles, whereas in the latter two cases the walker can always "remember" of his first steps. The question to be elucidated, and the was the main motivation of our work, is if memory of the historic initial is condition for observation anomalous diffusion (in this case, superdiffusion). We give a conclusive answer, by studying a non-Markovian model in which the walkers memory of the past, at time t, is given by a Gaussian centered at time t=2 and standard deviation t which grows linearly as the walker ages. For large widths of we find that the model behaves similarly to the Elephant model; In the opposite limit (! 0), although the walker forget the early days, we observed similar results to the Alzheimer walk model, in particular the presence of amnestically induced persistence, characterized by certain log-periodic oscillations. We conclude that the memory of earlier times is not a necessary condition for the generating of superdiffusion nor the amnestically induced persistence and can appear even in profiles of memory that forgets the initial steps, like the Gausssian memory profile investigated here.

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Durante a pesquisa visando à elaboração do relatório antropológico de Boa Vista dos Negros, comunidade quilombola do Seridó (RN), verificamos que o grupo conserva uma longa memória genealógica e que, apesar das mudanças ocorridas na organização econômica e social do grupo, as principais formas de solidariedade foram mantidas. Queremos, aqui, refletir sobre a importância da noção de família, a transmissão dos nomes e da memória genealógica na definição do território quilombola. Na ocasião, serão analisados como os elementos da cultura tradicional são ressignificados ao longo do processo de afirmação étnica

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CAVIGNAC, J. A. Mito e memória na construção de uma identidade local. Organon, Rio Grande do Sul, v. 21, n.42, jan./jun. 2007. Disponível em: . Acesso em:

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Caffeine is the most consumed psychostimulant, with effects on attention, memory, and arousal. But when this substance is ingested near to bedtime there is a decrease on sleep, interfering on mnemonic processes. So, our ain was to investigate how the caffeine ingested near to sleep onset acts on sleep and memory in marmosets. We used 16 adult marmosets, single housed, in a 12:12h light-dark cycle. For registering locomotor activity were used two kinds of sensors. The gyroscope sensor registers activity each 30 sec and detects motion with good accuracy. Because of this we used this sensor for detecting nocturnal activity. The second sensor was based on infrared and accumulates activity each 5 min and it’s not able to detect nocturnal activity, just diurnal activity. We also used camera for registering Rest phase of one marmoset. For the cognitive task, the animals needed to learn a rewarded context (CR) when compared to a non-rewarded context CNR). This experiment comprises 5 phases: 1) Two days of habituation to apparatus; 2)Training for 8 days; 3) oral administration of caffeine (10 mg/kg) or placebo administration ±1h before sleep onset, for 8 days, with marmosets receiving placebo or caffeine; 4) retraining to apparatus and after that, placebo administration (placebo group-GP), or caffeine administration (with continuous group-GC and acute groupGA); 5) Test, for evaluating learning to CR. The sessions were filmed and each one had 8 min of duration. At 7 am started the habituation, training and test sessions, and at 3:15 pm started retraining. The results for gyroscope sensor showed that there was coincidence of 68,57% with nocturnal register of the cameras. Then, the gyroscope sensors detected nocturnal activity for all experimental groups Moreover, when compared sensor gyroscope with sensor based on infrared, was observed that both sensor presented similarity on patterns of activity curve. When we observed the effects of caffeine on Activity-Rest Cycle in GP, GA and GC, is possible to see that that gyroscope sensors and based on infrared presented only intra group differences. As behavioral results, the marmosets learned to discriminate CR when compared to CNR. Moreover, GP presented deficits on memory recall during the test, and GA increased the memory recall, when both were compared to GP. We concluded that the marmosets were able to learning the cognitive task and that the caffeine ingested near to sleep onset acts modulating memory in these animals. Moreover the gyroscope sensor can be used as alternative tool for investigating nocturnal activity. Then, the utilization of this non-invasive device allows marmosets exhibit their behavior within the laboratory conditions as natural as possible.

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The hospital is a place of complex actions, where several activities for serving the population are performed such as: medical appointments, exams, surgeries, emergency care, admission in wards and ICUs. These activities are mixed with anxiety, impatience, despair and distress of patients and their families, issues involving emotional balance both for professionals who provide services for them as for people cared by them. The healthcare crisis in Brazil is getting worse every year and today, constitutes a major problem for private hospitals. The patient that comes to emergencies progressively increase, and in contrast, there is no supply of hospital beds in the same proportion, causing overcrowding, declines in the quality of care delivered to patients, drain of professionals of the health area and difficulty in management the beds. This work presents a study that seeks to create an alternative tool that can contribute to the management of a private hospital beds. It also seeks to identify potential issues or deficiencies and therefore make changes in flow for an increase in service capacity, thus reducing costs without compromising the quality of services provided. The tool used was the Computational Simulation –based in discrete event, which aims to identify the main parameters to be considered for a proper modeling of this system. This study took as reference the admission of a private hospital, based on the current scenario, where your apartments are in saturation level as its occupancy rate. The relocation of project beds aims to meet the growing demand for surgeries and hospital admissions observed by the current administration.

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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.

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The random walk models with temporal correlation (i.e. memory) are of interest in the study of anomalous diffusion phenomena. The random walk and its generalizations are of prominent place in the characterization of various physical, chemical and biological phenomena. The temporal correlation is an essential feature in anomalous diffusion models. These temporal long-range correlation models can be called non-Markovian models, otherwise, the short-range time correlation counterparts are Markovian ones. Within this context, we reviewed the existing models with temporal correlation, i.e. entire memory, the elephant walk model, or partial memory, alzheimer walk model and walk model with a gaussian memory with profile. It is noticed that these models shows superdiffusion with a Hurst exponent H > 1/2. We study in this work a superdiffusive random walk model with exponentially decaying memory. This seems to be a self-contradictory statement, since it is well known that random walks with exponentially decaying temporal correlations can be approximated arbitrarily well by Markov processes and that central limit theorems prohibit superdiffusion for Markovian walks with finite variance of step sizes. The solution to the apparent paradox is that the model is genuinely non-Markovian, due to a time-dependent decay constant associated with the exponential behavior. In the end, we discuss ideas for future investigations.

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This research starts from the presupposition that Cartilha do Silêncio(1997), a novel by the Brazilian writer Francisco Dantas, has a double articulated shift. One of the moves is towards the modern experience, with the idea that modernity is filled with contraries, as remarked by Nietzsche; the other is linked to the livelihoods ashore on traditional experiences, which encompasses the notion of memory as individual and collective ownership. The aim here is to analyze such perspective, social and critical issues within the characters' life stories that regards the calling of past as clear example that tradition is not gone, though modern life presents its own signs. Such dynamics gives to the plot a paradoxal feature. This work is mainly grounded on Marshall Berman' s thoughts in All That Is Solid Melts Into Air: The Experience of Modernity (1982) as well as on Antoine Compagnon'sFive Paradoxes of Modernity (1994). Assuming that Francisco Dantas' Novel is set as a split narrative, outcome of social memory originated on individual experiences aside social process and patriarchal family, this research brings into play the concept of memory by Jacques Le Goff in History and Memory (1992) along EcléaBosi's study in Memória e Sociedade: lembranças de velhos (1979). Keen to check how Cartilha do silêncio adjoins modern livelihoods with aesthetics order, the method articulates text and context, literary and social life, according to Antonio Candido'sLiteratura e Sociedade (1965). Thus, after reading the novel, it is possible to notice how the identity of the characters are built throughout the plot and it is also kept against settling on its social context during the transition from patriarchal tradition to modernity, creating a taut mood between both registries.

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The Brejuí Mine, situated in the municipality of Currais Novos (RN), was responsible for the local economy growth between the years of 1943 and 1990, causing the interest of miner's working class to its urban center. After the end of scheelita extraction, the mine became a "theme park", in 2004. The company left its mark on the city by building several monuments in reference to the mining activity and the company's founder, Tomaz Salustino. However, there are no written records that describe such activities on its early years, nor their pioneers in the mining subject. Therefore, it is important to investigate the miner’s memories and ask if, along the more than five decades that lasted the heyday of mining, an identity linked to the profession was built; the extent to which workers make reference to this history as membersand what are the symbols that are being triggered in the development of a working class identity. Further, I investigate what memory was mad concerning the pioneers, mostly farmers attracted by miner work. To do so, I make use of audiovisual archival resources and oral records of the interlocutors that were filmed in the preparations of the documentary “Lembranças de velhos garimpeiros". We have noticed that, in the script of the official history of the Brejuí Mine, the "boss" figure overlaps the workers and that the forms patronage, originated from the rural world, followed punctuating the social relations in the mine. Today, with the resumption of the mining activity, it is possible that the strengthening of the working class and the Seridó miner identity desire reborn.

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Introduction: Several modifications are identified as aging, causing more or less limitation imposed by over the years. Among these, one can highlight the different degrees of cognitive decline, particularly memory that can involve the daily activities and the subject functionality. Studies have shown an association between levels of serum cortisol and stress imposed by the exercise on this. However, there are few studies that references the performance on cognitive aspects of declarative memory and cortisol on the exercise in the water with automatic and práxicos movements and moderate. Objective: Check the effect based on the acute physical exercise and práxicos automatic movements on the performance of visual declarative memory and in serum cortisol in subjects aged between 51 and 74 years. Materials and Methods: It builds a survey characterized as cross with a first sample of 32 physically active subjects aged between 51 and 74 years, divided into two exercise groups (March of Automatic Group - MAG and the March of Praxis Group - MPG). We used a probabilistic and random sampling for sample selection. Used the MMSE (Mini Mental State Examination) to check the general cognitive status, visual acuity test - optotypes chart "E" Rasquin and was even used the declarative visual memory test proposed by Nitrini and collaborators (1994), applying before motor stimulation and immediately after, and the day of blood collection with 2 ml for analysis of cortisol hormone. The normality and homogeneity were verified from the Shapiro-Wilk and Levene tests. Thus we adopted a descriptive statistics to characterize the sample. The Split-Plot ANOVA was used along with the paired t-test to verify the identified differences. We adopted a significance level of p <0.05. Results: It was observed that the groups (MAG and MPG) and the anthropometric variables, perceived exertion, education, cognitive assessment and visual acuity showed no significant differences (p > 0.05), showing that the groups are homogeneous, with variables and similar means. After the stimulation session, lasting 30 min, it was observed that the amount of hits for Δ of declarative memory questionnaire visual images increased, presenting significant for both groups (MAG, p < 0.001; MPG, p = 0.042). The same was observed for cortisol concentration with a reduction in the levels immediately after the stimulus (MAG and MPG, p < 0.001). Conclusion: The results showed that the exercises proposed in its acute effect provide significantly memories of gains and also showed a reduction in cortisol levels.