588 resultados para Mechanical behaviours,
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Substance use behaviors of young people attending a special school are reported over a 4-year period from the age of 12-16 years. The article investigated these behaviors by surveying a cohort of young people with a statement for moderate learning disabilities annually during the last 4 years of compulsory schooling. The findings show that these young people consistently reported lower levels of tobacco, alcohol, and cannabis use compared with those attending mainstream school. No other illicit drug use was reported. The potential implications of these findings are discussed in relation to the context and timing of targeted substance education and prevention initiatives for young people with moderate learning disability attending a special school.This resource was contributed by The National Documentation Centre on Drug Use.
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Chronic growth hormone (GH) hypersecretion in rats leads to increased isometric force without affecting the unloaded shortening velocity of isolated cardiac papillary muscles, despite a marked isomyosin shift toward V3. To determine if alterations occurred at the level of the contractile proteins in rats bearing a GH-secreting tumor (GH rats), we examined the mechanical properties of skinned fibers to eliminate the early steps of the excitation-contraction coupling mechanism. We found that maximal active tension and stiffness at saturating calcium concentrations (pCa 4.5) were markedly higher in GH rats than in control rats (tension, 52.9 +/- 5.2 versus 38.1 +/- 4.6 mN.mm-2, p < 0.05; stiffness, 1,105 +/- 120 versus 685 +/- 88 mN.mm-2.microns-1, p < 0.01), whereas values at low calcium concentrations (pCa 9) were unchanged. In addition, the calcium sensitivity of the contractile proteins was slightly but significantly higher in GH rats than in control rats (delta pCa 0.04, p < 0.001). The crossbridge cycling rate, reflected by the response to quick length changes, was lower in GH rats than in control rats (62.0 +/- 2.6 versus 77.4 +/- 6.6 sec-1, p < 0.05), in good agreement with a decrease in the proportion of alpha-myosin heavy chains in the corresponding papillary muscles (45.5 +/- 2.0% versus 94.6 +/- 2.4%, p < 0.001). The changes in myosin heavy chain protein phenotype were paralleled by similar changes of the corresponding mRNAs, indicating that the latter occurred mainly at a pretranslational level. These results demonstrate that during chronic GH hypersecretion in rats, alterations at the myofibrillar level contribute to the increase in myocardial contractility observed in intact muscle.
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These synthetic estimates were produced as part of a research project to test and produce area-level estimates of healthy lifestyle behaviours, which was carried out at the National Centre for Social Research. The estimates were produced in response to the twin requirements to develop small area estimates for Neighbourhood Statistics and to meet local public health information needs. Synthetic estimates with 95% Confidence Intervals (1) have been prepared using 2000-2002 data from the Health Survey for England, the 2001 Census and other information, at the 2003 Census Area Statistics (CAS) ward and Primary Care Organisation (PCO)(2) geographic level for the following variables: Prevalence of current smoking (at the time the data was collected); Obesity of adults; Binge drinking for adults; Consumption of 5 or more portions of fruit and vegetables a day (adults); Consumption of 3 or more portions of fruit and vegetables day (children).
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Mechanical load-induced intracellular signaling events are important for subsequent skeletal muscle hypertrophy. We previously showed that load-induced activation of the cation channel TRPV1 caused an increase in intracellular calcium concentrations ([Ca ( 2+) ]i) and that this activated mammalian target of rapamycin (mTOR) and promoted muscle hypertrophy. However, the link between mechanical load-induced intracellular signaling events, and the TRPV1-mediated increases in [Ca ( 2+) ]i are not fully understood. Here we show that administration of the TRPV1 agonist, capsaicin, induces phosphorylation of mTOR, p70S6K, S6, Erk1/2 and p38 MAPK, but not Akt, AMPK or GSK3β. Furthermore, the TRPV1-induced phosphorylation patterns resembled those induced by mechanical load. Our results continue to highlight the importance of TRPV1-mediated calcium signaling in load-induced intracellular signaling pathways.
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AIMS: To investigate empirically the hypothesized relationship between counsellor motivational interviewing (MI) skills and patient change talk (CT) by analysing the articulation between counsellor behaviours and patient language during brief motivational interventions (BMI) addressing at-risk alcohol consumption. DESIGN: Sequential analysis of psycholinguistic codes obtained by two independent raters using the Motivational Interviewing Skill Code (MISC), version 2.0. SETTING: Secondary analysis of data from a randomized controlled trial evaluating the effectiveness of BMI in an emergency department. PARTICIPANTS: A total of 97 patients tape-recorded when receiving BMI. MEASUREMENTS: MISC variables were categorized into three counsellor behaviours (MI-consistent, MI-inconsistent and 'other') and three kinds of patient language (CT, counter-CT (CCT) and utterances not linked with the alcohol topic). Observed transition frequencies, conditional probabilities and significance levels based on odds ratios were computed using sequential analysis software. FINDINGS: MI-consistent behaviours were the only counsellor behaviours that were significantly more likely to be followed by patient CT. Those behaviours were significantly more likely to be followed by patient change exploration (CT and CCT) while MI-inconsistent behaviours and 'other' counsellor behaviours were significantly more likely to be followed by utterances not linked with the alcohol topic and significantly less likely to be followed by CT. MI-consistent behaviours were more likely after change exploration, whereas 'other' counsellor behaviours were more likely only after utterances not linked with the alcohol topic. CONCLUSIONS: Findings lend support to the hypothesized relationship between MI-consistent behaviours and CT, highlight the importance of patient influence on counsellor behaviour and emphasize the usefulness of MI techniques and spirit during brief interventions targeting change enhancement.
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To create an instrument to be used in an outpatient clinic to detect adolescents prone to risk-taking behaviours. Based on previous research, five identified variables (relationship with parents and teachers, liking going to school, average grades, and level of religiosity) were used to create a screening tool to detect at least one of ten risky behaviours (tobacco, alcohol, cannabis and other illegal drugs use; sexual intercourse and sexual risky behaviour; driving while intoxicated, riding with an intoxicated driver, not always using a seat belt, and not always using a helmet). The instrument was tested using the Barcelona Adolescent Health Survey 1993. A Receiver Operating Characteristics curve was used to find the best cut-off point between high and low risk score. Odds ratios and 95% confidence intervals were calculated to detect at least one risky behaviour and for each individual behaviour. In order to assess its predictive value, the analysis was repeated using the Barcelona Adolescent Health Survey 1999. In both cases, analyses were conducted for the whole sample and for younger and older adolescents. Adolescents with a high-risk score were more likely to take at least one risky behaviour both when the whole sample was analysed and by age groups. With very few exceptions, the Behaviour Evaluation for Risk-Taking Adolescents showed significant odds ratios for each individual variable. CONCLUSION: The Behaviour Evaluation for Risk-Taking Adolescents has shown its potential as an easy to use instrument to screen for risk-taking behaviours. Future research must aim towards assessing this instrument's predictive value in the clinical setting and it's application to other populations.
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BACKGROUND: A growing body of literature indicates that adolescents with chronic conditions are as likely, or more likely, to take risky behaviours than their healthy peers. The objective of this research was to assess whether adolescents with chronic illness in Catalonia differ from their healthy peers in risk-taking behaviour. METHODS: Data were drawn from the Catalonia Adolescent Health database, a survey including a random school-based sample of 6952 young people, aged 14-19 years. The index group (IG) included 665 adolescents (450 females) reporting several chronic conditions. The comparison group (CG) comprised 6287 healthy adolescents (3306 females). Personal, family and school-related variables were analysed to ensure comparability between groups. Sexual behaviour, drug use (tobacco, alcohol, cannabis, cocaine and synthetic drugs) and perception of drug use among peers and in school were compared. Analysis was carried out separately by gender. chi-square, Fisher's and Student's tests were used to compare categorical and continuous variables. RESULTS: The prevalence of chronic conditions was 9.6%, with females showing a higher prevalence than males. The IG showed similar or higher rates of sexual intercourse and risky sexual behaviour. For most studied drugs, IG males reported slightly lower rates of use than CG males, while IG females showed higher rates for every drug studied. No differences were found in the perceptions of drug use among peers or in their school. CONCLUSIONS: Similar to previous research, chronically ill adolescents in our sample are as likely, or more likely, to take risky behaviours than their healthy counterparts and should receive the same anticipatory guidance.
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PURPOSE: The origin of the slow component is not fully understood. The mechanical hypothesis is one of the potential factors, because an increase in external mechanical work with fatigue was previously reported for a constant velocity run. The purpose of this study was to determine whether a change in mechanical work could occur during the development of the VO2 slow component under the effect of fatigue. METHODS: Twelve regional-level competitive runners performed a square-wave transition, corresponding to 95% of the speed associated with peak VO2 obtained during an incremental test. The VO2 response was fit with a classical model including two exponential functions. A specific treadmill with three-dimensional force transducers was used to measure the ground reaction force. Kinetic work (W(kin)), potential work (W(pot)), external work (W(ext)), and an index of internal work (W(int)) per unit of distance were quantified continuously. RESULTS: During the slow component of VO2, a significant increase in W (P< 0.01), no change in W, and a significant decrease in W and W index (P< 0.05, P< 0.001, respectively) were observed. CONCLUSION: The present study showed that the slow component of VO2 did not result partly from a change in mechanical work under the effect of fatigue. Nevertheless, the decrease in stride frequency (P< 0.001) and contact time (P< 0.001) suggested an alternative mechanical explanation. The slow component during running may be due to the cost of generating force or to alterations in the storage and recoil of elastic energy, and not to the external mechanical work.
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To date, myxoma on a mechanical valve annulus has not been reported. The case is reported of a 74-year-old woman who was admitted to hospital following the identification of an intracardiac tumor mass. Six years previously, the patient had received a mechanical valve implanted in the mitral position. Transesophageal echocardiography revealed a mobile hypoechogenic tumorous mass attached to the anterior annulus of the prosthesis. The tumor was successfully treated by surgical excision, and a diagnosis of myxoma was confirmed both clinically and pathologically.
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Mechanical ventilation (MV) is life-saving but potentially harmful for lungs of premature infants. So far, animal models dealt with the acute impact of MV on immature lungs, but less with its delayed effects. We used a newborn rodent model including non-surgical and therefore reversible intubation with moderate ventilation and hypothesized that there might be distinct gene expression patterns after a ventilation-free recovery period compared to acute effects directly after MV. Newborn rat pups were subjected to 8 hr of MV with 60% oxygen (O(2) ), 24 hr after injection of lipopolysaccharide (LPS), intended to create a low inflammatory background as often recognized in preterm infants. Animals were separated in controls (CTRL), LPS injection (LPS), or full intervention with LPS and MV with 60% O(2) (LPS + MV + O(2) ). Lungs were recovered either directly following (T:0 hr) or 48 hr after MV (T:48 hr). Histologically, signs of ventilator-induced lung injury (VILI) were observed in LPS + MV + O(2) lungs at T:0 hr, while changes appeared similar to those known from patients with chronic lung disease (CLD) with fewer albeit larger gas exchange units, at T:48 hr. At T:0 hr, LPS + MV + O(2) increased gene expression of pro-inflammatory MIP-2. In parallel anti-inflammatory IL-1Ra gene expression was increased in LPS and LPS + MV + O(2) groups. At T:48 hr, pro- and anti-inflammatory genes had returned to their basal expression. MMP-2 gene expression was decreased in LPS and LPS + MV + O(2) groups at T:0 hr, but no longer at T:48 hr. MMP-9 gene expression levels were unchanged directly after MV. However, at T:48 hr, gene and protein expression increased in LPS + MV + O(2) group. In conclusion, this study demonstrates the feasibility of delayed outcome measurements after a ventilation-free period in newborn rats and may help to further understand the time-course of molecular changes following MV. The differences obtained from the two time points could be interpreted as an initial transitory increase of inflammation and a delayed impact of the intervention on structure-related genes. Pediatr Pulmonol. 2012; 47:1204-1214. © 2012 Wiley Periodicals, Inc.
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In a search for new sensor systems and new methods for underwater vehicle positioning based on visual observation, this paper presents a computer vision system based on coded light projection. 3D information is taken from an underwater scene. This information is used to test obstacle avoidance behaviour. In addition, the main ideas for achieving stabilisation of the vehicle in front of an object are presented
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Purpose. This study was conducted to determine whether newer infrared or laser welding technologies created joints superior to traditional furnace or torch soldering methods of joining metals. It was designed to assess the mechanical resistance, the characteristics of the fractured surfaces, and the elemental diffusion of joints obtained by four different techniques: (1) preceramic soldering with a propane-oxygen torch, (2) postceramic soldering with a porcelain furnace, (3) preceramic and (4) postceramic soldering with an infrared heat source, and (5) laser welding. Material and methods. Mechanical resistance was determined by measuring the ultimate tensile strength of the joint and by determining their resistance to fatigue loading. Elemental diffusion to and from the joint was assessed with microprobe tracings. Scanning electron microscopy micrographs of the fractured surface were also obtained and evaluated. Results. Under monotonic tensile stress, three groups emerged: The laser welds were the strongest, the preceramic joints ranged second, and the postceramic joints were the weakest. Under fatigue stress, the order was as follows: first, the preceramic joints, and second, a group that comprised both postceramic joints and the laser welds. Inspection of the fractographs revealed several fracture modes but no consistent pattern emerged. Microprobe analyses demonstrated minor diffusion processes in the preceramic joints, whereas significant diffusion was observed in the postceramic joints. Clinical Implications. The mechanical resistance data conflicted as to the strength that could be expected of laser welded joints. On the basis of fatigue resistance of the joints, neither infrared solder joints nor laser welds were stronger than torch or furnace soldered joints.
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Verbal auditory hallucinations can have a strong impact on the social and professional functioning of individuals diagnosed with schizophrenia. The safety-seeking behaviours used to reduce the threat associated with voices play a significant role in explaining the functional consequences of auditory hallucinations. Nevertheless, these safety-seeking behaviours have been little studied. Twenty-eight patients with schizophrenia and verbal auditory hallucinations were recruited for this study. Hallucinations were evaluated using the Psychotic Symptom Rating Scale and the Belief About Voice Questionnaire and safety behaviours using a modified version of the Safety Behaviour Questionnaire. Our results show that the vast majority of patients relies on safety behaviours to reduce the threat associated with voices. This reliance on safety behaviours is mostly explained by beliefs about origin of voices the omnipotence attributed to hallucinations and the behavioural and emotional reactions to the voices. Safety-seeking behaviours play an important role in maintaining dysfunctional beliefs with respect to voices. They should be better targeted within the cognitive and behavioural therapies for auditory hallucinations.