965 resultados para arm activity monitoring


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Neurally adjusted ventilatory assist (NAVA) is a ventilation assist mode that delivers pressure in proportionality to electrical activity of the diaphragm (Eadi). Compared to pressure support ventilation (PS), it improves patient-ventilator synchrony and should allow a better expression of patient's intrinsic respiratory variability. We hypothesize that NAVA provides better matching in ventilator tidal volume (Vt) to patients inspiratory demand. 22 patients with acute respiratory failure, ventilated with PS were included in the study. A comparative study was carried out between PS and NAVA, with NAVA gain ensuring the same peak airway pressure as PS. Robust coefficients of variation (CVR) for Eadi and Vt were compared for each mode. The integral of Eadi (ʃEadi) was used to represent patient's inspiratory demand. To evaluate tidal volume and patient's demand matching, Range90 = 5-95 % range of the Vt/ʃEadi ratio was calculated, to normalize and compare differences in demand within and between patients and modes. In this study, peak Eadi and ʃEadi are correlated with median correlation of coefficients, R > 0.95. Median ʃEadi, Vt, neural inspiratory time (Ti_ ( Neural )), inspiratory time (Ti) and peak inspiratory pressure (PIP) were similar in PS and NAVA. However, it was found that individual patients have higher or smaller ʃEadi, Vt, Ti_ ( Neural ), Ti and PIP. CVR analysis showed greater Vt variability for NAVA (p < 0.005). Range90 was lower for NAVA than PS for 21 of 22 patients. NAVA provided better matching of Vt to ʃEadi for 21 of 22 patients, and provided greater variability Vt. These results were achieved regardless of differences in ventilatory demand (Eadi) between patients and modes.

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To assess the effectiveness of a school based physical activity programme during one school year on physical and psychological health in young schoolchildren. Cluster randomised controlled trial. 28 classes from 15 elementary schools in Switzerland randomly selected and assigned in a 4:3 ratio to an intervention (n=16) or control arm (n=12) after stratification for grade (first and fifth grade), from August 2005 to June 2006. 540 children, of whom 502 consented and presented at baseline. Children in the intervention arm (n=297) received a multi-component physical activity programme that included structuring the three existing physical education lessons each week and adding two additional lessons a week, daily short activity breaks, and physical activity homework. Children (n=205) and parents in the control group were not informed of an intervention group. For most outcome measures, the assessors were blinded. Primary outcome measures included body fat (sum of four skinfolds), aerobic fitness (shuttle run test), physical activity (accelerometry), and quality of life (questionnaires). Secondary outcome measures included body mass index and cardiovascular risk score (average z score of waist circumference, mean blood pressure, blood glucose, inverted high density lipoprotein cholesterol, and triglycerides). 498 children completed the baseline and follow-up assessments (mean age 6.9 (SD 0.3) years for first grade, 11.1 (0.5) years for fifth grade). After adjustment for grade, sex, baseline values, and clustering within classes, children in the intervention arm compared with controls showed more negative changes in the z score of the sum of four skinfolds (-0.12, 95 % confidence interval -0.21 to -0.03; P=0.009). Likewise, their z scores for aerobic fitness increased more favourably (0.17, 0.01 to 0.32; P=0.04), as did those for moderate-vigorous physical activity in school (1.19, 0.78 to 1.60; P<0.001), all day moderate-vigorous physical activity (0.44, 0.05 to 0.82; P=0.03), and total physical activity in school (0.92, 0.35 to 1.50; P=0.003). Z scores for overall daily physical activity (0.21, -0.21 to 0.63) and physical quality of life (0.42, -1.23 to 2.06) as well as psychological quality of life (0.59, -0.85 to 2.03) did not change significantly. A school based multi-component physical activity intervention including compulsory elements improved physical activity and fitness and reduced adiposity in children. Trial registration Current Controlled Trials ISRCTN15360785.

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BACKGROUND: Glioblastoma multiforme (GBM), a highly invasive and vascular cancer, responds poorly to conventional cytotoxic therapy. Integrins, widely expressed in GBM and tumor vasculature, mediate cell survival, migration and angiogenesis. Cilengitide is a potent alphavbeta3 and alphavbeta5 integrin inhibitor. OBJECTIVE: To summarize the preclinical and clinical experience with cilengitide for GBM. METHODS: Preclinical studies and clinical trials evaluating cilengitide for GBM were reviewed. RESULTS/CONCLUSIONS: Cilengitide is active and synergizes with external beam radiotherapy in preclinical GBM models. In clinical trials for recurrent GBM, single-agent cilengitide has antitumor benefits and minimal toxicity. Among newly diagnosed GBM patients, single-arm studies incorporating cilengitide into standard external beam radiotherapy/temozolomide have shown encouraging activity with no increased toxicity and have led to a planned randomized Phase III trial.

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Beliefs about the rightness or wrongness of engaging in various antisocial acts, referred to here as nonnative beliefs legitimizing antisocial behaviour (nblab), have been shown to playa role in the emergence oflater antisocial behaviour. The current study represented an attempt to understand whether parental monitoring and parent-child attachment have differential relationships with these antisocial nonnative beliefs in adolescents of different temperaments. The participants, 7135 adolescents in 25 high schools (ages 10- 18 years, M = 15.7) completed a wide-ranging questionnaire as part of the broad Youth Lifestyle Choices - Community University Research Alliance project, whose goal is to identify and describe the major developmental pathways of risk behaviours and resilience in youth. Two aspects of monitoring (monitoring knowledge and surveillance/tracking), attachment security, and two measures of temperament (activity level and approach) were examined for main effects and in interactions as predictors of adolescent nonnative beliefs. All of these measures were based on adolescent self-ratings on either 3- or 4-point Likert-type scales. Several important results emerged from the study. Males were higher than females in nblab; parental monitoring knowledge and adolescent attachment security were negatively related to nblab; and temperamental activity level was positively related. Monitoring knowledge, the strongest of the predictors, was much more strongly related to nonnative beliefs than was parental surveillance/tracking, supporting the contention that it is how much parents actually know, and not their surveillance efforts, that predict adolescent nonnative beliefs. A surprising finding that is of the utmost importance was that, although several of the interactions tested were significant, none were considered to be of a meaningful magnitude (defined as sr^ > .01). The current study supported the suggestion that normative beliefs legitimizing antisocial behaviour are multiply determined, and the results were discussed with respect to the observed differential relations of parental monitoring, parent-child attachment, temperament, age, and gender to antisocial normative beliefs in adolescents. Also discussed were the need to test other parenting, temperament, and other variables that may be involved in the development of nblab; the need to directly test possible mechanisms explaining the links among the variables; and the usefulness of longitudinal research in determining possible directions of causality and developmental changes in the relationships.

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The ability to monitor and evaluate the consequences of ongoing behaviors and coordinate behavioral adjustments seems to rely on networks including the anterior cingulate cortex (ACC) and phasic changes in dopamine activity. Activity (and presumably functional maturation) of the ACC may be indirectly measured using the error-related negativity (ERN), an event-related potential (ERP) component that is hypothesized to reflect activity of the automatic response monitoring system. To date, no studies have examined the measurement reliability of the ERN as a trait-like measure of response monitoring, its development in mid- and late- adolescence as well as its relation to risk-taking and empathic ability, two traits linked to dopaminergic and ACC activity. Utilizing a large sample of 15- and 18-year-old males, the present study examined the test-retest reliability of the ERN, age-related changes in the ERN and other components of the ERP associated with error monitoring (the Pe and CRN), and the relations of the error-related ERP components to personality traits of risk propensity and empathy. Results indicated good test-retest reliability of the ERN providing important validation of the ERN as a stable and possibly trait-like electrophysiological correlate of performance monitoring. Ofthe three components, only the ERN was of greater amplitude for the older adolescents suggesting that its ACC network is functionally late to mature, due to either structural or neurochemical changes with age. Finally, the ERN was smaller for those with high risk propensity and low empathy, while other components associated with error monitoring were not, which suggests that poor ACe function may be associated with the desire to engage in risky behaviors and the ERN may be influenced by the extent of individuals' concern with the outcome of events.

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Reduced capacity for executive cognitive function and for the autonomic control of cardiac responsivity are both concomitants of the aging process. These may be linked through their mutual dependence on medial prefrontal function, but the specifics ofthat linkage have not been well explored. Executive functions associated with medial prefrontal cortex involve various aspects ofperformance monitoring, whereas centrally mediated autonomic functions can be observed as heart rate variability (HRV), i.e., variability in the length of intervals between heart beats. The focus for this thesis was to examine the degree to which the capacity for phasic autonomic adjustments to heart rate relates to performance monitoring in younger and older adults, using measures of electrocortical and autonomic activity. Behavioural performance and attention allocation during two age-sensitive tasks could be predicted by various aspects of autonomic control. For young adults, greater influence of the parasympathetic system on HRV was beneficial for learning unfamiliar maze paths; for older adults, greater sympathetic influence was detrimental to these functions. Further, these relationships were primarily evoked when the task required the construction and use of internalized representations of mazes rather than passive responses to feedback. When memory for source was required, older adults made three times as many source errors as young adults. However, greater parasympathetic influence on HRV in the older group was conducive to avoiding source errors and to reduced electrocortical responses to irrelevant information. Higher sympathetic predominance, in contrast, was associated with higher rates of source error and greater electrocortical responses tq non-target information in both groups. These relations were not seen for 11 errors associated with a speeded perceptual task, irrespective of its difficulty level. Overall, autonomic modulation of cardiac activity was associated with higher levels of performance monitoring, but differentially across tasks and age groups. With respect to age, those older adults who had maintained higher levels of autonomic cardiac regulation appeared to have also maintained higher levels of executive control over task performance.

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Objective: Overuse injuries in violinists are a problem that has been primarily analyzed through the use of questionnaires. Simultaneous 3D motion analysis and EMG to measure muscle activity has been suggested as a quantitative technique to explore this problem by identifying movement patterns and muscular demands which may predispose violinists to overuse injuries. This multi-disciplinary analysis technique has, so far, had limited use in the music world. The purpose of this study was to use it to characterize the demands of a violin bowing task. Subjects: Twelve injury-free violinists volunteered for the study. The subjects were assigned to a novice or expert group based on playing experience, as determined by questionnaire. Design and Settings: Muscle activity and movement patterns were assessed while violinists played five bowing cycles (one bowing cycle = one down-bow + one up-bow) on each string (G, D, A, E), at a pulse of 4 beats per bow and 100 beats per minute. Measurements: An upper extremity model created using coordinate data from markers placed on the right acromion process, lateral epicondyle of the humerus and ulnar styloid was used to determine minimum and maximum joint angles, ranges of motion (ROM) and angular velocities at the shoulder and elbow of the bowing arm. Muscle activity in right anterior deltoid, biceps brachii and triceps brachii was assessed during maximal voluntary contractions (MVC) and during the playing task. Data were analysed for significant differences across the strings and between experience groups. Results: Elbow flexion/extension ROM was similar across strings for both groups. Shoulder flexion/extension ROM increaslarger for the experts. Angular velocity changes mirrored changes in ROM. Deltoid was the most active of the muscles assessed (20% MVC) and displayed a pattern of constant activation to maintain shoulder abduction. Biceps and triceps were less active (4 - 12% MVC) and showed a more periodic 'on and off pattern. Novices' muscle activity was higher in all cases. Experts' muscle activity showed a consistent pattern across strings, whereas the novices were more irregular. The agonist-antagonist roles of biceps and triceps during the bowing motion were clearly defined in the expert group, but not as apparent in the novice group. Conclusions: Bowing movement appears to be controlled by the shoulder rather than the elbow as shoulder ROM changed across strings while elbow ROM remained the same. Shoulder injuries are probably due to repetition as the muscle activity required for the movement is small. Experts require a smaller amount of muscle activity to perform the movement, possibly due to more efficient muscle activation patterns as a result of practice. This quantitative multidisciplinary approach to analysing violinists' movements can contribute to fuller understanding of both playing demands and injury mechanisms .

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The purpose of this study was to determine the influence of an ongoing cognitive task on an individual’s ability to generate a compensatory arm response. Twenty young and 16 older adults recovered their balance from a support surface translation while completing a cognitive (counting) task of varying difficulty. Surface electromyographic (EMG) recordings from the shoulders and kinematics of the right arm were collected to quantify the compensatory arm response. Results indicated that the counting task, regardless of its difficulty as well as the age of the individual, had minimal influence on the onset or magnitude of arm muscle activity that occurred following a loss of balance. In contrast to previous research, this study’s findings suggest that the cortical or cognitive resources utilized by the cognitive task are not relied upon for the generation of compensatory arm responses and that older adults are not disproportionately affected by dual-tasking than young adults.

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Iron pillared Montmorillonite has been synthesised and it is then wet impregnated with vanadia with different vanadia composition. These catalysts are characterised using conventional techniques such as XRD analysis,FTIR analysis and surface area and pore volume measurements. Acidity is measured using spectrophotometric monitoring of adsorption of perylene, thermogravimetric desorption of 2.6 dimethylpyridine and temperature programmed desorption of ammonia. Activity studies are done in the liquid phase. It has been concluded that Lewis acidic sites are responsible for the benzylation of toluene when the benzylating agent is benzyl chloride while Bronsted acidic sites are responsible when the reagent is benzyl alcohol.

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Chromia loaded sulfated titania has been synthesized via sol–gel route with different chromia loadings. These catalysts are characterized using conventional techniques such as XRD analysis, FTIR analysis, surface area and pore volume measurements, EDX, SEM and UV–Vis diffuse reflectance spectral analysis. Acidity is measured using spectrophotometric monitoring of adsorption of perylene, thermogravimetric desorption of 2,6-dimethylpyridine and temperature programmed desorption of ammonia. Activity studies are done in the liquid phase. It has been concluded that Lewis acid sites are responsible for the benzylation of arenes with benzyl chloride.

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Introducción: La hipertensión arterial es un problema de salud pública tanto en países industrializados como en vía de desarrollo. Su prevalencia en la infancia viene en aumento por lo que es relevante determinarla en niños preescolares a nivel local. Objetivo: Determinar la prevalencia de hipertensión arterial en niños de tres a cinco años de una cohorte de 14 hogares infantiles del ICBF de la localidad de Usaquén en Bogotá. Materiales y métodos: Se realizó un estudio de corte transversal analítico, utilizando la base de datos de un ensayo aleatorizado y controlado del año 200913, y se evaluaron las cifras de tensión arterial de acuerdo a sexo, edad, talla y su correlación con el IMC con un nivel de confianza del 95% y precisión del 1%. Se calcularon las medias, desviaciones estándar, percentiles y prevalencia. Resultados: Se obtuvo una muestra de 1035 casos, encontrándose una prevalencia de 4,5% de HTA sistólica, 10,4% de diastólica, ambas en estadio I; teniendo en cuenta tanto sistólica como diastólica, fue de 11,6% en estadio I. Se determinaron los valores de presión arterial sistólica y diastólica en cuartiles de acuerdo a edad, sexo y talla. El coeficiente de correlación entre el IMC y los niveles de presión arterial sistólica y diastólica fueron de 0.0992 y 0.0362 respectivamente. Conclusión: La prevalencia de HTA general fue de 11,6%, predominando la diastólica en estadio I en niños preescolares. No se encontró correlación entre el IMC y las cifras de tensión arterial sistólica y diastólica.

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Aquesta tesi es basa en el programa de reintroducció de la llúdriga eurasiàtica (Lutra lutra) a les conques dels rius Muga i Fluvià (Catalunya) durant la segona meitat dels 1990s. Els objectius de la tesi foren demostrar la viabilitat de la reintroducció, demostrar l'èxit de la mateixa, estudiar aspectes ecològics i etològics de l'espècie, aprofitant l'oportunitat única de gaudir d'una població "de disseny" i determinar les probabilitats de supervivència de la població a llarg termini. La reintroducció de la llúdriga a les conques dels rius Muga i Fluvià va reeixir, doncs l'àrea geogràfica ocupada efectivament es va incrementar fins a un 64% d'estacions positives a l'hivern 2001-02. La troballa de tres exemplars adults nascuts a l'àrea de reintroducció és una altra prova que valida l'èxit del programa. La densitat d'exemplars calculada a través dels censos visuals ha resultat baixa (0.04-0.11 llúdrigues/km), però s'aproxima al que hom pot esperar en els primers estadis d'una població reintroduïda, encara poc nombrosa però distribuïda en una gran àrea. La mortalitat post-alliberament va ser del 22% un any després de l'alliberament, similar o inferior a la d'altres programes de reintroducció de llúdrigues reeixits. La mortalitat va ser deguda principalment a atropellaments (56%). El patró d'activitat de les llúdrigues reintroduïdes va esdevenir principalment nocturn i crepuscular, amb una escassa activitat diürna. Les seves àrees vitals van ser del mateix ordre (34,2 km) que les calculades en d'altres estudis realitzats a Europa. La longitud mitjana de riu recorreguda per una llúdriga durant 24 hores va ser de 4,2 km per les femelles i 7,6 km pels mascles. Durant el període de radioseguiment dues femelles van criar i els seus moviments van poder ser estudiats amb deteniment. La resposta de la nova població de llúdrigues a les fluctuacions estacionals en la disponibilitat d'aigua, habitual a les regions mediterrànies, va consistir en la concentració en una àrea menor durant el període de sequera estival, a causa de l'increment de trams secs, inhabitables per la llúdriga per la manca d'aliment, fet que va provocar expansions i contraccions periòdiques en l'àrea de distribució. La persistència a llarg termini de la població reintroduïda va ser estudiada mitjançant una Anàlisi de Viabilitat Poblacional (PVA). El resultat va ser un baix risc d'extinció de la població en els propers 100 anys i la majoria dels escenaris simulats (65%) van assolir el criteri d'un mínim de 90% de probabilitat de supervivència. Del model poblacional construït es dedueix que un punt clau per assegurar la viabilitat de la població reintroduïda és la reducció de la mortalitat accidental. A l'àrea d'estudi, els atropellaments causen més del 50% de la mortalitat i aquesta pot ser reduïda mitjançant la construcció de passos de fauna, el tancament lateral d'alguns trams de carretera perillosos i el control de la velocitat en algunes vies. El projecte de reintroducció ha posat a punt un protocol per a la captura, maneig i alliberament de llúdrigues salvatges, que pot contenir informació útil per a programes similars. També ha suposat una oportunitat única d'estudiar una població dissenyada artificialment i poder comparar diversos mètodes per estimar la distribució i la densitat de poblacions de llúdrigues. Per últim, la reintroducció portada a terme a les conques dels rius Muga i Fluvià ha aconseguit crear una nova població de llúdrigues, que persisteix en el temps, que es reprodueix regularment i que es dispersa progressivament, fins i tot a noves conques fluvials.

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The aim of phase II single-arm clinical trials of a new drug is to determine whether it has sufficient promising activity to warrant its further development. For the last several years Bayesian statistical methods have been proposed and used. Bayesian approaches are ideal for earlier phase trials as they take into account information that accrues during a trial. Predictive probabilities are then updated and so become more accurate as the trial progresses. Suitable priors can act as pseudo samples, which make small sample clinical trials more informative. Thus patients have better chances to receive better treatments. The goal of this paper is to provide a tutorial for statisticians who use Bayesian methods for the first time or investigators who have some statistical background. In addition, real data from three clinical trials are presented as examples to illustrate how to conduct a Bayesian approach for phase II single-arm clinical trials with binary outcomes.

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Movements and activity patterns of an adult radio-tagged female brown bear accompanied by her cubs were documented for the first time in Rodopi area (NE Greece) from August 2000 to July 2002. Average daily movements were 2.45 +/- 2.26 SD km, (range 0.15-8.5 km). The longest daily range could be related to human disturbance (hunting activity). The longest seasonal distance (211 km), during Summer 2001 coincided with the dissolution of the family. With cubs, the female was more active during daytime (73 % of all radio-readings) than when solitary (28 %). The female switched to a more crepuscular behaviour, after separation from the yearling (July 2001). According to pooled data from 924 activity - recording sessions, during the whole monitoring period, the female was almost twice as active during day time while rearing cubs (51 % active) than when solitary (23 %). The autumn and early winter home range size of the family was larger (280 km(2)) than after the separation from the cubs (59 km(2)). During the family group phase, home range size varied from 258 km(2) in autumn to 40 km(2) in winter (average denning period lasted 107 days : December 2000-March 2001). The bear hibernated in the Bulgarian part of the Rodopi Range during winters of 2001 and 2002.

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The relationship between individual growth and acetylcholinesterase (AChE).activity was evaluated for Daphnia magna. Analysis on the influence of two different culture media on baseline AChE activity was performed with Daphnia similis. The results indicated an inverse relationship between D. magna body length and AChE activity. An increase in total protein, which was not proportional to an increase in the rate of the substrate hydrolysis (Delta absorbance/min), seems to be the reason for this inverse size versus AChE activity relationship. Therefore, toxicants such as phenobarbital, which affect protein and size but not AChE activity directly, have an overall affect on AChE activity. In contrast, the AChE inhibitor parathion altered AChE activity but not protein. Culture medium also had a significant affect on AChE activity in D. similis. Changes in total protein seem to be the main reason for the variations in baseline AChE activity in Daphnia observed in the different evaluations performed in this work. Therefore, AChE activity in Daphnia must be interpreted carefully, and variations related to changes in total protein must be taken into account when applying this enzyme as a biomarker in biological monitoring.