986 resultados para Forced desynchronization
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Objective: Cannabidiol is a chemical constituent from Cannabis sativa and it has multiple mechanisms of action, including antidepressant effects. The main objective of the present study was to evaluate behavioural and molecular effects induced by administration of cannabidiol and imipramine in rats. Methods: In the present study, rats were acutely or chronically treated for 14 days once a day with saline, cannabidiol (15, 30 and 60 mg/kg) or imipramine (30 mg/kg) and the animals behaviour was assessed in forced swimming and open-field tests. Afterwards, the prefrontal cortex, hippocampus and amygdala brain-derived neurotrophic factor (BDNF) levels were assessed by enzyme-linked immunosorbent sandwich assay. Results: We observed that both acute and chronic treatments with imipramine at the dose of 30 mg/kg and cannabidiol at the dose of 30 mg/kg reduced immobility time and increased swimming time; climbing time was increased only with imipramine at the dose of 30 mg/kg, without affecting locomotor activity. In addition, chronic treatment with cannabidiol at the dose of 15 mg/kg and imipramine at the dose of 30 mg/kg increased BDNF levels in the rat amygdala. Conclusion: In conclusion, our results indicate that cannabidiol has an antidepressant-like profile and could be a new pharmacological target for the treatment of major depression.
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The discipline of public health and preventive medicine in Australia and New Zealand had its genesis in the advocacy of 18th and 19th century military pioneers. Military (Royal Navy and British Army) surgeons were posted to Australia as part of their non-discretionary duty. Civilian doctors emigrated variously for adventure, escapism and gold fever. One group, a particularly influential group disproportionate to their numbers, came in one sense as forced emigrants because of chronic respiratory disease in general, and tuberculosis in particular. Tuberculosis was an occupational hazard of 19th century medical and surgical practice throughout western Europe. This paper analyses six examples of such emigration which had, perhaps unforeseen at the time, significant results in the advancement of public health. Such emigration was in one sense voluntary, but in another was forced upon the victims in their quest for personal survival. In Australia, such medical individuals became leading advocates and successful catalysts for change in such diverse fields as social welfare, public health, the preventive aspects of medical practice, child health, nutrition and medical education. A number of such public health pioneers today have no physical memorials; but their influence is to be seen in the ethos of medical practice in Australia and New Zealand today. Their memory is further perpetuated in the names of Australian native wildflowers and trees that symbolise not only a healthy environment but the longterm investment, accrued with interest, of the institution of public health measures for which their advocacy achieved much success.
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The interplay of seasonality, the system's nonlinearities and intrinsic stochasticity, is studied for a seasonally forced susceptible-exposed-infective-recovered stochastic model. The model is explored in the parameter region that corresponds to childhood infectious diseases such as measles. The power spectrum of the stochastic fluctuations around the attractors of the deterministic system that describes the model in the thermodynamic limit is computed analytically and validated by stochastic simulations for large system sizes. Size effects are studied through additional simulations. Other effects such as switching between coexisting attractors induced by stochasticity often mentioned in the literature as playing an important role in the dynamics of childhood infectious diseases are also investigated. The main conclusion is that stochastic amplification, rather than these effects, is the key ingredient to understand the observed incidence patterns.
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In this paper we consider a complex-order forced van der Pol oscillator. The complex derivative Dα1jβ, with α, β ∈ ℝ+, is a generalization of the concept of an integer derivative, where α = 1, β = 0. The Fourier transforms of the periodic solutions of the complex-order forced van der Pol oscillator are computed for various values of parameters such as frequency ω and amplitude b of the external forcing, the damping μ, and parameters α and β. Moreover, we consider two cases: (i) b = 1, μ = {1.0, 5.0, 10.0}, and ω = {0.5, 2.46, 5.0, 20.0}; (ii) ω = 20.0, μ = {1.0, 5.0, 10.0}, and b = {1.0, 5.0, 10.0}. We verified that most of the signal energy is concentrated in the fundamental harmonic ω0. We also observed that the fundamental frequency of the oscillations ω0 varies with α and μ. For the range of tested values, the numerical fitting led to logarithmic approximations for system (7) in the two cases (i) and (ii). In conclusion, we verify that by varying the parameter values α and β of the complex-order derivative in expression (7), we accomplished a very effective way of perturbing the dynamical behavior of the forced van der Pol oscillator, which is no longer limited to parameters b and ω.
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An adaptive control damping the forced vibration of a car while passing along a bumpy road is investigated. It is based on a simple kinematic description of the desired behavior of the damped system. A modified PID controller containing an approximation of Caputo’s fractional derivative suppresses the high-frequency components related to the bumps and dips, while the low frequency part of passing hills/valleys are strictly traced. Neither a complete dynamic model of the car nor ’a priori’ information on the surface of the road is needed. The adaptive control realizes this kinematic design in spite of the existence of dynamically coupled, excitable internal degrees of freedom. The method is investigated via Scicos-based simulation in the case of a paradigm. It was found that both adaptivity and fractional order derivatives are essential parts of the control that can keep the vibration of the load at bay without directly controlling its motion.
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Time-lapse crosshole ground-penetrating radar (GPR) data, collected while infiltration occurs, can provide valuable information regarding the hydraulic properties of the unsaturated zone. In particular, the stochastic inversion of such data provides estimates of parameter uncertainties, which are necessary for hydrological prediction and decision making. Here, we investigate the effect of different infiltration conditions on the stochastic inversion of time-lapse, zero-offset-profile, GPR data. Inversions are performed using a Bayesian Markov-chain-Monte-Carlo methodology. Our results clearly indicate that considering data collected during a forced infiltration test helps to better refine soil hydraulic properties compared to data collected under natural infiltration conditions
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In the canton de Vaud, General Practioners (GPs) caring for asylum seekers under the "aide d'urgence" regime can ask for an adaptation of their housing conditions, by filling out a specific form and addressing it to the medical commission responsible for advising the EVAM (the housing institution for asylum seekers) on these issues. The forms addressed to the commission are indicative of a worrisome state of health in this population, especially for mental health. More than 70% report at least one psychiatric diagnosis. Most frequent are anxiety and depressive disorders, as well as many posttraumatic stress disorders, associated with traumatic events both in the country of origin and in Switzerland. Adapting the housing conditions, based on vulnerabilities that the GP has specifically documented, may contribute to improve the health of the most vulnerable asylum seekers.
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Populations displaced as a result of mass violent conflict have become one of the most pressing humanitarian concerns of the last decades. They have also become one salient political issue as a perceived burden (in economic and security terms) and as an important piece in the shift towards a more interventionist paradigm in the international system, based on both humanitarian and security grounds. The saliency of these aspects has detracted attention from the analysis of the interactions between relocation processes and violent conflict. Violent conflict studies have also largely ignored those interactions as a result of the consideration of these processes as mere reaction movements determined by structural conditions. This article takes the view that individual’s agency is retained during such processes, and that it is consequential, calling for the need to introduce a micro perspective. Based on this, a model for the individual’s decision of return is presented. The model has the potential to account for the dynamics of return at both the individual and the aggregate level. And it further helps to grasp fundamental interconnections with violent conflict. Some relevant conclusions are derived for the case of Bosnia-Herzegovina and about the implications of the politicization of return.
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Introduction. Respiratory difficulties in athletes are common, especially in adolescents, even in the absence of exercise-induced bronchoconstriction. Immaturity of the respiratory muscles coupling at high respiratory rates could be a potential mechanism. Whether respiratory muscle training (RMT) can positively influence it is yet unknown. Goal. We investigate the effects of RMT on ventilation and performance parameters in adolescent athletes and hypothesize that RMT will enhance respiratory capacity. Methods. 12 healthy subjects (8 male, 4 female, 17±0.5 years) from a sports/study high school class, competitively involved in various sports (minimum of 10 hours per week) underwent respiratory function testing, maximal minute ventilation (MMV) measurements and a maximal treadmill incremental test with VO2max and ventilatory thresholds (VT1 and VT2) determination. They then underwent one month of RMT (4 times/week) using a eucapnic hyperventilation device, with an incremental training program. The same tests were repeated after RMT. Results. Subjects completed 14.8 sessions of RMT, with an increase in total ventilation per session of 211±29% during training. Borg scale evaluation of the RMT session was unchanged or reduced in all subjects, despite an increase in total respiratory work. No changes (p>0.05) were observed pre/post RMT in VO2max (53.4±7.5 vs 51.6±7.7 ml/kg/min), VT2 (14.4±1.4 vs 14.0±1.1 km/h) or Speed max at end of test (16.1±1.7 vs 15.8±1.7 km/h). MVV increased by 9.2% (176.7±36.9 vs 192.9±32.6 l/min, p<0.001) and FVC by 3.3% (6.70±0.75 vs 4.85±0.76 litres, p<0.05). Subjective evaluation of respiratory sensations during exercise and daily living were also improved. Conclusions. RMT improves MMV and FVC in adolescent athletes, along with important subjective respiratory benefits, although no changes are seen in treadmill maximal performance tests and VO2max measurements. RMT can be easily performed in adolescent without side effects, with a potential for improvement in training capacity and overall well-being.
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This paper characterizes and evaluates the potential of three commercial CT iterative reconstruction methods (ASIR?, VEO? and iDose(4 ()?())) for dose reduction and image quality improvement. We measured CT number accuracy, standard deviation (SD), noise power spectrum (NPS) and modulation transfer function (MTF) metrics on Catphan phantom images while five human observers performed four-alternative forced-choice (4AFC) experiments to assess the detectability of low- and high-contrast objects embedded in two pediatric phantoms. Results show that 40% and 100% ASIR as well as iDose(4) levels 3 and 6 do not affect CT number and strongly decrease image noise with relative SD constant in a large range of dose. However, while ASIR produces a shift of the NPS curve apex, less change is observed with iDose(4) with respect to FBP methods. With second-generation iterative reconstruction VEO, physical metrics are even further improved: SD decreased to 70.4% at 0.5 mGy and spatial resolution improved to 37% (MTF(50%)). 4AFC experiments show that few improvements in detection task performance are obtained with ASIR and iDose(4), whereas VEO makes excellent detections possible even at an ultra-low-dose (0.3 mGy), leading to a potential dose reduction of a factor 3 to 7 (67%-86%). In spite of its longer reconstruction time and the fact that clinical studies are still required to complete these results, VEO clearly confirms the tremendous potential of iterative reconstructions for dose reduction in CT and appears to be an important tool for patient follow-up, especially for pediatric patients where cumulative lifetime dose still remains high.
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In most psychological tests and questionnaires, a test score is obtained bytaking the sum of the item scores. In virtually all cases where the test orquestionnaire contains multidimensional forced-choice items, this traditionalscoring method is also applied. We argue that the summation of scores obtained with multidimensional forced-choice items produces uninterpretabletest scores. Therefore, we propose three alternative scoring methods: a weakand a strict rank preserving scoring method, which both allow an ordinalinterpretation of test scores; and a ratio preserving scoring method, whichallows a proportional interpretation of test scores. Each proposed scoringmethod yields an index for each respondent indicating the degree to whichthe response pattern is inconsistent. Analysis of real data showed that withrespect to rank preservation, the weak and strict rank preserving methodresulted in lower inconsistency indices than the traditional scoring method;with respect to ratio preservation, the ratio preserving scoring method resulted in lower inconsistency indices than the traditional scoring method
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Case Number 91-151 Craig Gardner, an inmate in the Iowa prison system, was the subject of a force move by correctional officers while incarcerated at the Iowa State Penitentiary (ISP). This action involved the use of a chemical agent. This investigation began as a review of the use of a chemical agent in a forced cell move on June 30, 1991.
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Our aim was to evaluate the role of forced diuresis in improving the diagnostic accuracy of abdominopelvic (18)F-FDG PET. METHODS: Thirty-two patients were enrolled. Besides the presence of known intravesical tumors or undefined renal lesions on the initial PET scan, the inclusion criterion was the appearance of indeterminate or equivocal (18)F-FDG foci that extended along the course of the urinary tract and could not confidently be separated from urinary activity. For each patient, a second abdominopelvic PET study was performed after intravenous injection of 0.5 mg of furosemide per kilogram of body weight (maximum, 40 mg) coupled with parenteral infusion of physiologic saline. RESULTS: Forced diuresis coupled with parenteral hydration eliminated any significant (18)F-FDG activity from the lower urinary tract in 31 (97%) of 32 patients after the bladder had been voided 3 successive times. Twelve intravesical lesions were visualized with outstanding clarity, whereas radiologic suspicion of locally recurrent bladder tumors was ruled out in 3 patients. Among 14 indeterminate or equivocal extravesical foci, 7 were deemed of no clinical value because they disappeared after furosemide challenge, whereas 7 persisting foci were proven to be true-positive PET findings. The performance of (18)F-FDG PET in characterizing 3 renal-space-occupying lesions could not be improved by our protocol. CONCLUSION: Furosemide challenge has the potential to noninvasively resolve the inherent (18)F-FDG contrast handicap in the lower urinary tract.