A natureza da alma e o clinamen: ação e liberdade em Lucrécio

The concept of freedom and his presupposition, the free will or libera voluntas in Lucretius relies on the notion of clinamen (declination), an occasional and random motion of atoms, inaccessible to experience. It is endowed with a complex movement provided by spontaneity, without the need for mechanical causes. The action of perceiving (sensus) is selfconsciousness, according to which this will, illuminated by previous experiences (sensory, intellectual or emotional) of the soul, takes advantage of the freedom and own spontaneity of atomic motions to drive them to a perceived direction and chosen. On the other hand, if we consider that the declination has a predominant role for the acts of will, we are facing other problems and questions. There is always the choice of a determined action and, therefore, even if the individual is facing a need to act, is possible choose to do not continue finish this action. Thereby, the will is related to conditions that are originate, ultimately, from the images formed randomly in space and impress the soul: the simulacra of desire and pleasure. The declination itself is a very important notion in this research, in order to emphasize the relationship between the freedom and the kinetic of elements. The approach developed in this work had as main objective to investigate the philosophy of nature and the soul in Lucretius, their constituents and movement, as well as demonstrating how the notion of clinamen articulates with the concepts of image, desire and pleasure, proposing a possible interpretation for the declination as an indeterminate and ethical foundation of freedom

Propagação de danos no modelo de ising em redes de bravais e em fractais

In this work we have studied, by Monte Carlo computer simulation, several properties that characterize the damage spreading in the Ising model, defined in Bravais lattices (the square and the triangular lattices) and in the Sierpinski Gasket. First, we investigated the antiferromagnetic model in the triangular lattice with uniform magnetic field, by Glauber dynamics; The chaotic-frozen critical frontier that we obtained coincides , within error bars, with the paramegnetic-ferromagnetic frontier of the static transition. Using heat-bath dynamics, we have studied the ferromagnetic model in the Sierpinski Gasket: We have shown that there are two times that characterize the relaxation of the damage: One of them satisfy the generalized scaling theory proposed by Henley (critical exponent z~A/T for low temperatures). On the other hand, the other time does not obey any of the known scaling theories. Finally, we have used methods of time series analysis to study in Glauber dynamics, the damage in the ferromagnetic Ising model on a square lattice. We have obtained a Hurst exponent with value 0.5 in high temperatures and that grows to 1, close to the temperature TD, that separates the chaotic and the frozen phases

Influência do biofeedback no treino de marcha de sujeitos hemiparéticos: ensaio clínico randomizado

BACKGROUND: Treadmill training with partial body weight support (BWS) has shown many benefits for patients after a stroke. But their findings are not well known when combined with biofeedback. OBJETIVE: The purpose of this study was to evaluate the immediate effects of biofeedback, visual and auditory, combined with treadmill training with BWS on on walking functions of hemiplegic subjects. METHODS: We conducted a clinical trial, randomized controlled trial with 30 subjects in the chronic stage of stroke, underwent treadmill training with BWS (control), combined with visual biofeedback, given by the monitor of the treadmill through the symbolic appearance of feet as the subject gave the step; or auditory biofeedback, using a metronome with a frequency of 115% of the cadence of the individual. The subjects were evaluated by kinematics, and the data obtained by the Motion Analysis System Qualisys. To assess differences between groups and within each group after training was applied to ANOVA 3 x 2 repeated measures. RESULTS: There were no statistical differences between groups in any variable spatio-temporal and angular motion, but within each group there was an increase in walking speed and stride length after the training. The group of visual biofeedback increased the stance period and reduced the swing period and reason of symmetry, and the group auditory biofeedback reduced the double stance period. The range of motion of the knee and ankle and the plantar flexion increased in the visual biofeedback group. CONCLUSION: There are no differences between the immediate effects of gait training on a treadmill with BWS performed with and without visual or auditory biofeedback. However, the visual biofeedback can promote changes in a larger number of variables spatiotemporal and angular gait

Arquitetura com elevada taxa de processamento e reduzida largura de banda de memória para a estimação de movimento em vídeos digitais

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

Sismicidade e correlação com feições geológicas: o caso do lineamento Pernambuco e seu entorno

This thesis presents and discusses the results of the various seismic areas in the State of Pernambuco, with the aim of having a vision of regional seismicity and its causes. To the papers published in journals were added two new original works submitted to international journals, dealing with seismic areas located in the counties of São Caetano, Cupira, and Agrestina. All seismic areas mentioned in this thesis are located on the Pernambuco Lineament and its surroundings (both in branches or single faults within 40 km of it). The Pernambuco Lineament is a Neoproterozoic shear zone of continental-scale that deformed the Borborema Province, and presents as branches, shear zones with NE-SW direction. The new submitted papers are from the analysis of data collected by three local networks of stations that operated in the following areas: network SO07 (seismicity in the district of Santa Luzia - São Caetano, 2007), network BM10 (data from seismic areas of Serra Verde ( Cupira) and Barra do Chata (Agrestina), in 2010), network SO10 (seismicity near the urban center of São Caetano in 2010). These data were used for determining the hypocenters and focal mechanisms in order to discuss the relationship between the seismicity and geological features of the area. The new mechanisms obtained, as well as the previously published allowed the determination of the direction of the average stress in the region. The direction of stress in the region involving the various seismic areas, now or previously studied, is quite stable and approximate EW direction (SHmax). The correlation between seismicity and geological features is observed on the lineament and north of it. In the south (Cupira and Agrestina), in seismic areas nearby shear zones NE-SW, there is no correlation and seismogenic EW normal faults are active and its motion is compatible with regional stresses. It is probable that these active faults are more recent than the Neoproterozoic, probably of the Cretaceous period, when the last great movement of the Pernambuco Lineament occurred

A cafeína como agente modulador do ciclo atividade-repouso e memória em saguis (Callithrix jacchus)

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.