918 resultados para Forced return
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Background: Previous studies show that chronic hemiparetic patients after stroke, presents inabilities to perform movements in paretic hemibody. This inability is induced by positive reinforcement of unsuccessful attempts, a concept called learned non-use. Forced use therapy (FUT) and constraint induced movement therapy (CIMT) were developed with the goal of reversing the learned non-use. These approaches have been proposed for the rehabilitation of the paretic upper limb (PUL). It is unknown what would be the possible effects of these approaches in the rehabilitation of gait and balance. Objectives: To evaluate the effect of Modified FUT (mFUT) and Modified CIMT (mCIMT) on the gait and balance during four weeks of treatment and 3 months follow-up. Methods: This study included thirty-seven hemiparetic post-stroke subjects that were randomly allocated into two groups based on the treatment protocol. The non-paretic UL was immobilized for a period of 23 hours per day, five days a week. Participants were evaluated at Baseline, 1st, 2nd, 3rd and 4th weeks, and three months after randomization. For the evaluation we used: The Stroke Impact Scale (SIS), Berg Balance Scale (BBS) and Fugl-Meyer Motor Assessment (FM). Gait was analyzed by the 10-meter walk test (T10) and Timed Up & Go test (TUG). Results: Both groups revealed a better health status (SIS), better balance, better use of lower limb (BBS and FM) and greater speed in gait (T10 and TUG), during the weeks of treatment and months of follow-up, compared to the baseline. Conclusion: The results show mFUT and mCIMT are effective in the rehabilitation of balance and gait. Trial Registration ACTRN12611000411943.
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We studied locomotor activity rhythms of C57/Bl6 mice under a chronic jet lag (CJL) protocol (ChrA(6/2)), which consisted of 6-hour phase advances of the light-dark schedule (LD) every 2 days. Through periodogram analysis, we found 2 components of the activity rhythm: a short-period component (21.01 +/- 0.04 h) that was entrained by the LD schedule and a long-period component (24.68 +/- 0.26 h). We developed a mathematical model comprising 2 coupled circadian oscillators that was tested experimentally with different CJL schedules. Our simulations suggested that under CJL, the system behaves as if it were under a zeitgeber with a period determined by (24 -[phase shift size/days between shifts]). Desynchronization within the system arises according to whether this effective zeitgeber is inside or outside the range of entrainment of the oscillators. In this sense, ChrA(6/2) is interpreted as a (24 - 6/2 = 21 h) zeitgeber, and simulations predicted the behavior of mice under other CJL schedules with an effective 21-hour zeitgeber. Animals studied under an asymmetric T = 21 h zeitgeber (carried out by a 3-hour shortening of every dark phase) showed 2 activity components as observed under ChrA(6/2): an entrained short-period (21.01 +/- 0.03 h) and a long-period component (23.93 +/- 0.31 h). Internal desynchronization was lost when mice were subjected to 9-hour advances every 3 days, a possibility also contemplated by the simulations. Simulations also predicted that desynchronization should be less prevalent under delaying than under advancing CJL. Indeed, most mice subjected to 6-hour delay shifts every 2 days (an effective 27-hour zeitgeber) displayed a single entrained activity component (26.92 +/- 0.11 h). Our results demonstrate that the disruption provoked by CJL schedules is not dependent on the phase-shift magnitude or the frequency of the shifts separately but on the combination of both, through its ratio and additionally on their absolute values. In this study, we present a novel model of forced desynchronization in mice under a specific CJL schedule; in addition, our model provides theoretical tools for the evaluation of circadian disruption under CJL conditions that are currently used in circadian research.
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Nitric oxide (NO) is an atypical neurotransmitter that has been related to the pathophysiology of major depression disorder. Increased plasma NO levels have been reported in depressed and suicidal patients. Inhibition of neuronial nitric oxide synthase (nNOS), on the other hand, induces antidepressant effects in clinical and pre-clinical trials. The mechanisms responsible for the antidepressant-like effects of nNOS inhibitors, however, are not completely understood. In this study, genomic and proteomic analyses were used to investigate the effects of the preferential nNOS inhibitor 7-nitroindazole (7-NI) on changes in global gene and protein expression in the hippocampus of rats submitted to forced swimming test (FST). Chronic treatment (14 days, i.p.) with imipramine (15 mg/kg daily) or 7-NI (60 mg/kg daily) significantly reduced immobility in the FST. Saturation curves for Serial analysis of gene expression libraries showed that the hippocampus of animals submitted to FST presented a lower number of expressed genes compared to non-FST stressed groups. Imipramine, but not 7-NI, reverted this effect. GeneGo analyses revealed that genes related to oxidative phosphorylation, apoptosis and survival controlled by HTR1A signaling and cytoskeleton remodeling controlled by Rho GTPases were significantly changed by FST. 7-NI prevented this effect. In addition, 7-NI treatment changed the expression of genes related to transcription in the cAMP response element-binding pathway. Therefore, this study suggests that changes in oxidative stress and neuroplastic processes could be involved in the antidepressant-like effects induced by nNOS inhibition.
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This manuscript presents a review of the literature about medical leaves due to mental and behavioral disorders and return to work of teachers. There are scarce published manuscripts. Most articles relate with prevalence of mental disorders and factors associated with the work organization, and did not mention intervention proposals and or changes in the work organization and teaching work. Proposed actions are discussed.
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Human endothelial cells (ECs) have the ability to make up the lining of blood vessels. These cells are also capable of neovascularization and revascularization and have been applied in various clinical situations. With the aim of understanding the effect of NANOG superexpression on ECs, we transduced the Nanog gene into the ECs. Nanog is highly expressed in embryonic stem cells (ESCs) and is essential for pluripotency and self-renewal. However, Nanog can also be expressed in somatic stem cells, and this gene is related to great expansion capacity in vitro. We found that ECs expressing Nanog showed expression of other stemness genes, such as Sox2, FoxD3, Oct4, Klf4, c-myc, and beta-catenin, that are not normally expressed or are expressed at very low levels in ECs. Nanog is one of the stemness genes that can activate other stemness genes, and the upregulation of the Nanog gene seems to be critical for reprogramming cells. In this study, the introduction of Nanog was sufficient to alter the expression of key genes of the pluripotent pathway. The functional importance of Nanog for altering the cell expression profile and morphology was clearly demonstrated by our results.
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Analysis of the NCAR/NCEP Reanalysis show changes in the atmospheric circulation in the Southern hemisphere, with a strengthening and poleward displacement of the westerlies. Because the wind is one of the main sources of the ocean's kinetic energy, a numerical experiment with the Hybrid Coordinate Ocean Model (HYCOM) was forced with monthly means of the NCAR/NCEP Reanalysis products to investigate the effects of the changes in the wind on the ocean circulation in a geographical domain defined by 98W – 114E; 65S – 60N. The results show good agreement with other models and with available satellite data. In the western sector of the South Atlantic there are several indications of changes such as a poleward displacement of the Brazil-Malvinas Confluence and positive trends in temperature and salinity of the southwestern region of the subtropical gyre
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Analysis of the NCAR/NCEP Reanalysis show changes in the atmospheric circulation in the Southern hemisphere, with a strengthening and poleward displacement of the westerlies. Because the wind is one of the main sources of the ocean's kinetic energy, a numerical experiment with the Hybrid Coordinate Ocean Model (HYCOM) was forced with monthly means of the NCAR/NCEP Reanalysis products to investigate the effects of the changes in the wind on the ocean circulation in a geographical domain defined by 98W – 114E; 65S – 60N. The results show good agreement with other models and with available satellite data. In the western sector of the South Atlantic there are several indications of changes such as a poleward displacement of the Brazil-Malvinas Confluence and positive trends in temperature and salinity of the southwestern region of the subtropical gyre.
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Two types of mesoscale wind-speed jet and their effects on boundary-layer structure were studied. The first is a coastal jet off the northern California coast, and the second is a katabatic jet over Vatnajökull, Iceland. Coastal regions are highly populated, and studies of coastal meteorology are of general interest for environmental protection, fishing industry, and for air and sea transportation. Not so many people live in direct contact with glaciers but properties of katabatic flows are important for understanding glacier response to climatic changes. Hence, the two jets can potentially influence a vast number of people. Flow response to terrain forcing, transient behavior in time and space, and adherence to simplified theoretical models were examined. The turbulence structure in these stably stratified boundary layers was also investigated. Numerical modeling is the main tool in this thesis; observations are used primarily to ensure a realistic model behavior. Simple shallow-water theory provides a useful framework for analyzing high-velocity flows along mountainous coastlines, but for an unexpected reason. Waves are trapped in the inversion by the curvature of the wind-speed profile, rather than by an infinite stability in the inversion separating two neutral layers, as assumed in the theory. In the absence of blocking terrain, observations of steady-state supercritical flows are not likely, due to the diurnal variation of flow criticality. In many simplified models, non-local processes are neglected. In the flows studied here, we showed that this is not always a valid approximation. Discrepancies between simulated katabatic flow and that predicted by an analytical model are hypothesized to be due to non-local effects, such as surface inhomogeneity and slope geometry, neglected in the theory. On a different scale, a reason for variations in the shape of local similarity scaling functions between studies is suggested to be differences in non-local contributions to the velocity variance budgets.
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Programa de doctorado en Oceanografía
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Die James Bond-Filme: seit über 40 Jahren sind sie ein unübersehbarer Bestandteil der Populärkultur. Anfang der 60er Jahre unter völlig anderen historischen, sozialen und nicht zuletzt filmtechnischen Voraussetzungen aus der Taufe gehoben, gelingt es ihnen auch heute noch, ein Massenpublikum für sich zu gewinnen. Inwiefern kann man bei einer so langen Laufzeit überhaupt noch von einer homogenen Serie sprechen? Und was für Gemeinsamkeiten, Unterschiede und auch Weiterentwicklungen von der ursprünglichen Machart sind hier zu beobachten? Dies sind die Grundfragen der vorliegenden Dissertation. Bei der Benennung der seriellen Eigenschaften werden sowohl inhaltliche als auch dramaturgische und filmtechnisch-formale Aspekte betrachtet. Die Figurenkonstellation von Held, Gegenspieler und der weiblichen Hauptfigur, die zwischen den beiden steht und häufig die Seiten wechselt, ist ein Schema das - kaum variiert - schon in den Romanvorlagen Ian Flemings zum Einsatz kam und auch das Rückgrat der Film-Plots bildet. Dennoch ließ dieses Gerüst den mittlerweile fünf verschiedenen Darstellern, die James Bond nacheinander verkörperten, genügend Freiraum für das Ausarbeiten eines eigenen Rollenkonzepts, das auf ihren speziellen Schauspielstil ausgerichtet war. Dadurch erhielt die James Bond-Figur jeweils eine Neuinterpretation, die sich insbesondere in ihrem sozialen Habitus bemerkbar macht, der je nach Darsteller zwischen provokantem Aufsteigertyp und aristokratischem Gentleman changierte. Zum unverwechselbaren Erkennungsmerkmal der Bond-Serie avancierte die so genannte 'gun-barrel'-Sequenz, die in den ersten Sekunden jedes Films abläuft. Auch die sich anschließende Vortitelsequenz, eine auf Spannung oder Action angelegte Szene, die einen Vorgeschmack auf den folgenden Film liefern soll, ist ein Element, das der Machart von Fernsehserien entnommen ist. Neben diesen bewusst eingesetzten Markenzeichen lässt sich auch in der Gestaltungsweise der Filme - in Kameraführung, Schnitt, Musik und Set Design - eine stilistische Kontinuität feststellen, die insbesondere dadurch bedingt ist, dass die Serie seit jeher von den Produzenten ähnlich wie ein Familienunternehmen geführt wurde und - zumindest bis Ende der 80er Jahre - auch die kreativen Köpfe der Filme konsequent im eigenen Team ausgebildet wurden.
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The last decade has witnessed very fast development in microfabrication technologies. The increasing industrial applications of microfluidic systems call for more intensive and systematic knowledge on this newly emerging field. Especially for gaseous flow and heat transfer at microscale, the applicability of conventional theories developed at macro scale is not yet completely validated; this is mainly due to scarce experimental data available in literature for gas flows. The objective of this thesis is to investigate these unclear elements by analyzing forced convection for gaseous flows through microtubes and micro heat exchangers. Experimental tests have been performed with microtubes having various inner diameters, namely 750 m, 510 m and 170 m, over a wide range of Reynolds number covering the laminar region, the transitional zone and also the onset region of the turbulent regime. The results show that conventional theory is able to predict the flow friction factor when flow compressibility does not appear and the effect of fluid temperature-dependent properties is insignificant. A double-layered microchannel heat exchanger has been designed in order to study experimentally the efficiency of a gas-to-gas micro heat exchanger. This microdevice contains 133 parallel microchannels machined into polished PEEK plates for both the hot side and the cold side. The microchannels are 200 µm high, 200 µm wide and 39.8 mm long. The design of the micro device has been made in order to be able to test different materials as partition foil with flexible thickness. Experimental tests have been carried out for five different partition foils, with various mass flow rates and flow configurations. The experimental results indicate that the thermal performance of the countercurrent and cross flow micro heat exchanger can be strongly influenced by axial conduction in the partition foil separating the hot gas flow and cold gas flow.
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The Bedouin of South Sinai have been significantly affected by the politics of external powers for a long time. However, never had the interest of external powers in Sinai been so strong as since the Israeli-Egyptian wars in the second half of the 20th century when Bedouin interests started to collide with Egypt’s plans for a development of luxury tourism in South Sinai. rnrnThe tourism boom that has started in the 1980s has brought economic and infrastructure development to the Bedouin and tourism has become the most important source of income for the Bedouin. However, while the absolute increase of tourists to Sinai has trickled down to the Bedouin to some extent, the participation of Bedouin in the overall tourism development is under-proportionate. Moreover, the Bedouin have become increasingly dependent on monetary income and consequently from tourism as the only significant source of income while at the same time they have lost much of their land as well as their self-determination.rnrnIn this context, the Bedouin livelihoods have become very vulnerable due to repeated depressions in the tourism industry as well as marginalization. Major marginalization processes the Bedouin are facing are the loss of land, barriers to market entry, especially increasingly strict rules and regulations in the tourism industry, as well as discrimination by the authorities. Social differentiation and Bedouin preferences are identified as further factors in Bedouin marginalization.rnrnThe strategies Bedouin have developed in response to all these problems are coping strategies, which try to deal with the present problem at the individual level. Basically no strategies have been developed at the collective level that would aim to actively shape the Bedouin’s present and future. Collective action has been hampered by a variety of factors, such as the speed of the developments, the distribution of power or the decay of tribal structures.rnWhile some Bedouin might be able to continue their tourism activities, a large number of informal jobs will not be feasible anymore. The majority of the previously mostly self-employed Bedouin will probably be forced to work as day-laborers who will have lost much of their pride, dignity, sovereignty and freedom. Moreover, with a return to subsistence being impossible for the majority of the Bedouin, it is likely that an increasing number of marginalized Bedouin will turn to illegal income generating activities such as smuggling or drug cultivation. This in turn will lead to further repression and discrimination and could escalate in a serious violent conflict between the Bedouin and the government.rnrnDevelopment plans and projects should address the general lack of civil rights, local participation and protection of minorities in Egypt and promote Bedouin community development and the consideration of Bedouin interests in tourism development.rnrnWether the political upheavals and the resignation of president Mubarak at the beginning of 2011 will have a positive effect on the situation of the Bedouin remains to be seen.rn
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The main objective of this project is to experimentally demonstrate geometrical nonlinear phenomena due to large displacements during resonant vibration of composite materials and to explain the problem associated with fatigue prediction at resonant conditions. Three different composite blades to be tested were designed and manufactured, being their difference in the composite layup (i.e. unidirectional, cross-ply, and angle-ply layups). Manual envelope bagging technique is explained as applied to the actual manufacturing of the components; problems encountered and their solutions are detailed. Forced response tests of the first flexural, first torsional, and second flexural modes were performed by means of a uniquely contactless excitation system which induced vibration by using a pulsed airflow. Vibration intensity was acquired by means of Polytec LDV system. The first flexural mode is found to be completely linear irrespective of the vibration amplitude. The first torsional mode exhibits a general nonlinear softening behaviour which is interestingly coupled with a hardening behaviour for the unidirectional layup. The second flexural mode has a hardening nonlinear behaviour for either the unidirectional and angle-ply blade, whereas it is slightly softening for the cross-ply layup. By using the same equipment as that used for forced response analyses, free decay tests were performed at different airflow intensities. Discrete Fourier Trasform over the entire decay and Sliding DFT were computed so as to visualise the presence of nonlinear superharmonics in the decay signal and when they were damped out from the vibration over the decay time. Linear modes exhibit an exponential decay, while nonlinearities are associated with a dry-friction damping phenomenon which tends to increase with increasing amplitude. Damping ratio is derived from logarithmic decrement for the exponential branch of the decay.
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BACKGROUND: Several adverse consequences are caused by mild perioperative hypothermia. Maintaining normothermia with patient warming systems, today mostly with forced air (FA), has thus become a standard procedure during anesthesia. Recently, a polymer-based resistive patient warming system was developed. We compared the efficacy of a widely distributed FA system with the resistive-polymer (RP) system in a prospective, randomized clinical study. METHODS: Eighty patients scheduled for orthopedic surgery were randomized to either FA warming (Bair Hugger warming blanket #522 and blower #750, Arizant, Eden Prairie, MN) or RP warming (Hot Dog Multi-Position Blanket and Hot Dog controller, Augustine Biomedical, Eden Prairie, MN). Core temperature, skin temperature (head, upper and lower arm, chest, abdomen, back, thigh, and calf), and room temperature (general and near the patient) were recorded continuously. RESULTS: After an initial decrease, core temperatures increased in both groups at comparable rates (FA: 0.33 degrees C/h +/- 0.34 degrees C/h; RP: 0.29 degrees C/h +/- 0.35 degrees C/h; P = 0.6). There was also no difference in the course of mean skin and mean body (core) temperature. FA warming increased the environment close to the patient (the workplace of anesthesiologists and surgeons) more than RP warming (24.4 degrees C +/- 5.2 degrees C for FA vs 22.6 degrees C +/- 1.9 degrees C for RP at 30 minutes; P(AUC) <0.01). CONCLUSION: RP warming performed as efficiently as FA warming in patients undergoing orthopedic surgery.