954 resultados para Manipulation génétique


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective. A pilot investigation of the influence of different force levels on a treatment technique's hypoalgesic effect. Design. Randomised single blind repeated measures. Background. Optimisation of such biomechanical treatment variables as the point of force application, direction of force application and the level of applied manual force is classically regarded as the basis of best practice manipulative therapy. Manipulative therapy is frequently used to alleviate pain, a treatment effect that is often studied directly in the neurophysiological, paradigm and seldom in biomechanical research. The relationship between the level of force applied by a technique (e.g. biomechanics) and its hypoalgesic effect was the focus of this study. Method. The experiment involved the application of a lateral glide mobilisation with movement treatment technique to the symptomatic elbow of six subjects with lateral epicondylalgia. Four different levels of force, which were measured with a flexible pressure-sensing mat, were randomly applied while the subject performed a pain free grip strength test. Results. Standardised manual force data varied from 0.76 to 4.54 N/cm, lower-upper limits 95 Cl, respectively. Pain free grip strength expressed as a percentage change from pre-treatment values was significantly greater with manual forces beyond 1.9 N/cm (P = 0.014). Conclusions. This study, albeit a pilot, provides preliminary evidence that in terms of the hypoalgesic effect of a mobilisation with movement treatment technique, there may be an optimal level of applied manual force.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Aims : To study the effects of amylomaize starch and modified (carboxymethylated and acetylated) amylomaize starches on the composition of colonic bacteria and the production of volatile fatty acids, in mice. Methods and Results : Balb/c mice were fed with experimental diets containing various amount of amylomaize and modified amylomaize starches. Colonic bacterial populations and short-chain fatty acids were monitored. Results showed that the increases in indigenous bifidobacteria were detected in mice fed all starches tested; however, the highest numbers were observed in the group fed with 40% unmodified amylomaize starch. The starch type influenced the populations of indigenous Lactobacillus , Bacteroides and coliforms. High Lactobacillus numbers were achieved in the colon of mice fed with high concentration of amylomaize starch. Acetylated amylomaize starch significantly reduced the population of coliforms. In addition, orally dosed amylomaize utilizing bifidobacteria reached their highest levels when fed together with amylomaize or carboxymethylated amylomaize starch and in both cases butyrate levels were markedly increased. Conclusions: These results indicate that different amylomaize starches could generate desirable variation in gut microflora and that particular starches may be used to selectively modify gut function. Significance and Impact of Study: Amylomaize starch appeared to enhance the desirable composition of colonic bacteria in mice, and suggested it possessed the potential prebiotic properties.MTherefore, resistant starch and its chemical derivatives may exert beneficial impacts to the human colon.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Previous studies have demonstrated that the initial hypoalgesic effect of spinal manipulative therapy was not antagonized by naloxone and did not exhibit tolerance with repeated applications. The implication is that endogenous opioid mechanisms of pain relief are probably not at play in spinal manipulative therapy. The role of endogenous opioid peptides in manipulation of the peripheral joints has not been investigated. The aim of this study was to evaluate whether the initial hypoalgesic effect of a peripheral manipulative technique (mobilization-with-movement treatment for the elbow) demonstrated a tolerance to repeated applications (ie, reduction in magnitude of effect over repeated applications). Twenty-four participants with unilateral chronic lateral epicondylalgia participated in the study. A repeated measures study was conducted to examine the effect of repeated applications of the mobilization-with-movement treatment for the elbow on 6 separate treatment occasions at least 2 days apart. Pain-free grip strength and pressure pain threshold were chosen as the pain-related outcome measures. Changes in the percent maximum possible effect scores of measures of hypoalgesia were evaluated across the 6 treatment sessions by using linear trend analysis. The results showed no significant difference for the hypoalgesic effect of the treatment technique between sessions (P >.05). This peripheral manipulative therapy treatment technique appeared to have a similar effect profile to previously studied spinal manipulative therapy techniques, thereby contributing to the body of knowledge that indicates that manipulative therapy most likely induces a predominant non-opioid form of analgesia.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this text, we intend to explore the possibilities of sound manipulation in a context of augmented reality (AR) through the use of robots. We use the random behaviour of robots in a limited space for the real-time modulation of two sound characteristics: amplitude and frequency. We add the possibility of interaction with these robots, providing the user the opportunity to manipulate the physical interface by placing markers in the action space, which alter the behaviour of the robots and, consequently, the audible result produced. We intend to demonstrate through the agents, programming of random processes and direct manipulation of this application, that it is possible to generate empathy in interaction and obtain specific audible results, which would be difficult to otherwise reproduce due to the infinite loops that the interaction promotes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

DESIGN: A randomized controlled trial.OB JECTIVE: To investigate the immediate effects on pressure pain thresholds over latent trigger points (TrPs) in the masseter and temporalis muscles and active mouth opening following atlanto-occipital joint thrust manipulation or a soft tissue manual intervention targeted to the suboccipital muscles. BACKGROUND : Previous studies have described hypoalgesic effects of neck manipulative interventions over TrPs in the cervical musculature. There is a lack of studies analyzing these mechanisms over TrPs of muscles innervated by the trigeminal nerve. METHODS: One hundred twenty-two volunteers, 31 men and 91 women, between the ages of 18 and 30 years, with latent TrPs in the masseter muscle, were randomly divided into 3 groups: a manipulative group who received an atlanto-occipital joint thrust, a soft tissue group who received an inhibition technique over the suboccipital muscles, and a control group who did not receive an intervention. Pressure pain thresholds over latent TrPs in the masseter and temporalis muscles, and active mouth opening were assessed pretreatment and 2 minutes posttreatment by a blinded assessor. Mixed-model analyses of variance (ANOVA) were used to examine the effects of interventions on each outcome, with group as the between-subjects variable and time as the within-subjects variable. The primary analysis was the group-by-time interaction. RESULTS: The 2-by-3 mixed-model ANOVA revealed a significant group-by-time interaction for changes in pressure pain thresholds over masseter (P<.01) and temporalis (P =.003) muscle latent TrPs and also for active mouth opening (P<.001) in favor of the manipulative and soft tissue groups. Between-group effect sizes were small. CONCLUSIONS: The application of an atlanto-occipital thrust manipulation or soft tissue technique targeted to the suboccipital muscles led to an immediate increase in pressure pain thresholds over latent TrPs in the masseter and temporalis muscles and an increase in maximum active mouth opening. Nevertheless, the effects of both interventions were small and future studies are required to elucidate the clinical relevance of these changes. LEVEL OF EVIDENCE : Therapy, level 1b. J Orthop Sports Phys Ther 2010;40(5):310-317. doi:10.2519/jospt.2010.3257. KEYWORDSDS: cervical manipulation, muscle trigger points, neck, TMJ, upper cervical.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents a fractional calculus perspective in the study of signals captured during the movement of a mechanical manipulator carrying a liquid container. In order to study the signals an experimental setup is implemented. The system acquires data from the sensors, in real time, and, in a second phase, processes them through an analysis package. The analysis package runs off-line and handles the recorded data. The results show that the Fourier spectrum of several signals presents a fractional behavior. The experimental study provides useful information that can assist in the design of a control system and the trajectory planning to be used in reducing or eliminating the effect of vibrations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Chiropractic's popularity is rising among the general population. Moreover, few studies have been conducted to properly evaluate its safety. We report three cases of serious neurological adverse events in patients treated with chiropractic manipulation. The first case is a 41 years old woman who developed a vertebro-basilar stroke 48 h after cervical manipulation. The second case represents a 68 years old woman who presented a neuropraxic injury of both radial nerves after three sessions of spinal manipulation. The last case is a 34 years old man who developed a cervical epidural haematoma after a chiropractic treatment for neck pain. In all three cases there were criteria to consider a causality relation between the neurological adverse events and the chiropractic manipulation. The described serious adverse events promptly recommend the implementation of a risk alert system.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A new method for the study and optimization of manu«ipulator trajectories is developed. The novel feature resides on the modeling formulation. Standard system desciptions are based on a set of differential equations which, in general, require laborious computations and may be difficult to analyze. Moreover, the derived algorithms are suited to "deterministic" tasks, such as those appearing in a repetitivework, and are not well adapted to a "random" operation that occurs in intelligent systems interacting with a non-structured and changing environment. These facts motivate the development of alternative models based on distinct concepts. The proposed embedding of statistics and Fourier trasnform gives a new perspective towards the calculation and optimization of the robot trajectories in manipulating tasks.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The development of integrated measures which involve sterile mate release to supplement the conventional insecticidal techniques used in controlagainst insects of medical importance, raised the question, whether the vectors of Chagas'disease possess the natural mechanisms by manipulation of which they may be controlled. Results of earlier expenments, that had been published previously, were restricted to fragmentary information that raised various questions, the answer to which became available in the study herein described. Interspecific hybrids were produced from reciprocal crosses between T. pseudomaculata and T. sórdida and from unilateral crosses between female T. pseudomaculata and male. T. infestans. These females mated with males, laid less than the normal complement of eggs, but offspring was relatively abundant. When T. pseudomaculata females were paired with T. brasiliensis males, hybridization was more difficult because few of the females mated and those that did had a strongly reduced fertility. Adults emerged from ali crosses but exhibited sex disproportion, females predominating in all populations but one. The two Rhodnius species tested were also found to cross, but only when female R. prolixus were paired with male R. neglectus. These females laid a relatively high complement o f eggs, had a strongly reduced fertility, but 50% of the fertile eggs developed into vigorous adults, males predominating females. Neither type of hybrid male elicited fertilized eggs from either parental type of female, through their vesicula seminal is were found to be packed with spermatozoa, some normal looking and moving, others underdeveloped and motionless. Although, no artificial insemination was performed, the sperm in itself did not appear to be the prime inducer of sterility. Females paired with these hybrids did mate, sperm was transfered, as evidenced by the discharged spermatophores smeared with sperm, but did notcontain spermatozoa in their spermatecae. The failure of the sperm to migrate to the spermatecae indicate prezygotic pos-copulation incompatibility, thus the hybrid male can't be used to suppress populations. The female hybrids mated with parent males of either species had reduced fertility and ther sons were sterile as were those of their fertile daughters. However, continous backcrossing of the hybrid females and their female progeny to parental males partially restored fertility of the males and increased fertility of females, as scored by egg hatchability. Fertility of hybrid females, measured by the yield of adults capable to reproduce, indicated that the reproductive perfomance decreased when hybrid females and their daughters were backcrossed additional generations to parental males. It is tentatively suggested that hybrid females could be used for suppression if they compete efficiently with wild females.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Salmonella enterica serovars are Gram-negative facultative intracellular bacterial pathogens that infect a wide variety of animals. Salmonella infections are common in humans, causing usually typhoid fever and gastrointestinal diseases. Salmonella enterica serovar Typhimurium (S. Typhimurium), which is a leading cause of human gastroenteritis, has been extensively used to study the molecular pathogenesis of Salmonella, because of the availability of sophisticated genetic tools, and of suitable animal and tissue culture models mimicking different aspects of Salmonella infections.(...)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Rational manipulation of mRNA folding free energy allows rheostat control of pneumolysin production by Streptococcus pneumoniae

Relevância:

20.00% 20.00%

Publicador:

Resumo:

El control de propiedades hidrodinámicas capaces de influir en la mecánica de ruptura y poración de sistemas lamelares o membranas es de fundamental interés para diferentes aplicaciones biotecnológicas. Resulta de particular interés la conexión entre los procesos microscópicos relacionados al tipo de moléculas o unidades básicas, el orden determinado en el auto-ensamblado de las mismas y la dinámica local del sistema, con las propiedades físicas que determinan el comportamiento macroscópico bajo estimulación acústica. Resultados logrados recientemente sugieren la existencia de resonancias hidrodinámicas que podrian ser utilizadas para lograr la inestabilidad del sistema a baja potencia acústica. Se realizaran estudios experimentales utilizando principalmente técnicas que combinan resonancia magnética nuclear (RMN) y la sonicación de la muestra. También se realizarán estudios teóricos y simulaciones numéricas que permitan modelar los sistemas bajo estudio. Se propone dar continuidad al desarrollo de una técnica de relaxometría magnética nuclear en la cual se estimula acústicamente a la muestra durante el proceso de relajación magnética nuclear, y continuar la implementación de técnicas de RMN con resolución espacial que permitan complementar los estudios mencionados. Se espera comprender los mecanismos físicos que determinan la estabilidad de fases lamelares, logrando un modelo verificable y consistente que permita relacionar las propiedades mecánicas e hidrodinámicas con las propiedades de orden y dinámica molecular. Asimismo, se espera lograr avances en el desarrollo de las técnicas experimentales involucradas. La importancia del proyecto radica en el enfoque del problema. A diferencia de casi la totalidad de los estudios reportados, nuestro interés se enfoca en mecanismos de interacción entre la membrana y el campo acústico que sean eficientes a baja potencia acústica, en un régimen donde los gradientes térmicos y la cavitación sean despreciables.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We consider exchange markets with heterogeneous indivisible goods. We are interested in exchange rules that are efficient and immune to manipulations via endowments (either with respect to hiding or destroying part of the endowment or transferring part of the endowment to another trader). We consider three manipulability axioms: hiding-proofness, destruction-proofness, and transfer-proofness. We prove that no rule satisfying efficiency and hiding-proofness (which implies individual rationality) exists. For two-agent exchange markets with separable and responsive preferences, we show that efficient, individually rational, and destruction-proof rules exist. However, for separable preferences, no rule satisfies efficiency, individual rationality, and destruction-proofness. In the case of transfer-proofness the compatibility with efficiency and individual rationality for the two-agent case extends to the unrestricted domain. For exchange markets with separable preferences and more than two agents no rule satisfies efficiency, individual rationality, and transfer-proofness.