71 resultados para bandwidth 2.0 GHz to 2.45 GHz


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The Australian freshwater fish Murray cod, Maccullochella peelii peelii (Mitchell) is gaining popularity as a suitable species for intensive culture, particularly in closed systems. The aim of this study was to evaluate the performance of Murray cod in response to different feeding schedules. Growth, survival, food conversion and a range of other related parameters including carcass proximate composition were evaluated for fish in five feed management regimes. The feeding regimes used in the experiment were hand fed to satiation twice daily (SAT), a pre-determined ration of 1.2% of the body weight day−1 which was hand fed twice daily (HFR), and belt fed through the day only (B/D), belt fed through the night only (B/N) and belt fed for 24 h (B/DN). Each of the five feeding regimes was randomly allocated to three tanks (triplicates). All of the feeding regimes used a commercially prepared diet formulated specifically for Murray cod, containing ≈50% protein and ≈16% lipid. The experiment was conducted for 84 days. Specific growth rate ranged from 0.89±0.01 to 1.07±0.04% day−1. Food conversion ratio (FCR) ranged from 1.09±0.02 to 0.92±0.03. The fastest growth and greatest final body weight were observed in the SAT treatment; however, the highest FCR, visceral fat index (VFI %) and hepatosomatic index (HSI %) were also observed in this treatment. Significant differences were found in specific growth rate and final mean weight between fish in the B/D and SAT treatments. B/N and B/DN feeding regimes appeared to result in the most favourable fish performance.

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The purpose of the study was to quantify the strength of motor unit synchronization and coherence from pairs of concurrently active motor units before and after short-term (4–8 weeks) strength training of the left first dorsal interosseous (FDI) muscle. Five subjects (age 24.8 ± 4.3 years) performed a training protocol three times/week that consisted of six sets of ten maximal isometric index finger abductions, whereas three subjects (age 27.3 ± 6.7 years) acted as controls. Motor unit activity was recorded from pairs of intramuscular electrodes in the FDI muscle with two separate motor unit recording sessions obtained before and after strength training (trained group) or after 4 weeks of normal daily activities that did not involve training (control group). The training intervention resulted in a 54% (45.2 ± 8.3 to 69.5 ± 13.8 N, P = 0.001) increase in maximal index finger abduction force, whereas there was no change in strength in the control group. A total of 163 motor unit pairs (198 single motor units) were examined in both subject groups, with 52 motor unit pairs obtained from 10 recording sessions before training and 51 motor unit pairs from 10 recording sessions after training. Using the cross-correlation procedure, there was no change in the strength of motor unit synchronization following strength training (common input strength index; 0.71 ± 0.41 to 0.67 ± 0.43 pulses/s). Furthermore, motor unit coherence z scores at low (0–10 Hz; 3.9 ± 0.3 before to 4.4 ± 0.4 after) or high (10–30 Hz; 1.7 ± 0.1 before to 1.9 ± 0.1 after) frequencies were not influenced by strength training. These motor unit data indicate that increases in strength following several weeks of training a hand muscle are not accompanied by changes in motor unit synchronization or coherence, suggesting that these features of correlated motor unit activity are not important in the expression of muscle strength.

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Aims: To evaluate the efficacy of interventions to promote a healthy diet and physical activity in people with impaired glucose tolerance (IGT). Methods: A randomised controlled trial in Newcastle upon Tyne, UK, 1995–98. Participants included 67 adults (38 men; 29 women) aged 24–75 years with IGT. The intervention consisted of regular diet and physical activity counselling based on the stages of change model. Main outcome measures were changes between baseline and 6 months in nutrient intake; physical activity; anthropometric and physiological measurements including serum lipids; glucose tolerance; insulin sensitivity. Results: The difference in change in total fat consumption was significant between intervention and control groups (difference −21.8 (95% confidence interval (CI) −37.8 to −5.8) g/day, P=0.008). A significantly larger proportion of intervention participants reported taking up vigorous activity than controls (difference 30.1, (95% CI 4.3–52.7)%, P=0.021). The change in body mass index was significantly different between groups (difference −0.95 (95% CI −1.5 to −0.4) kg/m2, P=0.001). There was no significant difference in change in mean 2-h plasma glucose between groups (difference −0.19 (95% CI −1.1 to 0.71) mmol/l, NS) or in serum cholesterol (difference 0.02 (95% CI −0.26 to 0.31) mmol/l, NS). The difference in change in fasting serum insulin between groups was significant (difference −3.4 (95% CI −5.8 to −1.1) mU/l, P=0.005). Conclusions: After 6 months of intensive lifestyle intervention in participants with IGT, there were changes in diet and physical activity, some cardiovascular risk factors and insulin sensitivity, but not glucose tolerance. Further follow-up is in progress to investigate whether these changes are sustained or augmented over 2 years.

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The effect of finishing extensive farming period, to reduce fat content and manipulate the fatty acid profile of fish muscle, was evaluated in rainbow trout. Fish were stocked in an artificial lake, in which fish were fed only on naturally available nutrients with no supply of artificial feed, for different lengths of time from 0 to 120 days. No weight loss was noted during the whole finishing period while total length increased from 228±7 to 269±3 mm and the condition factor decreased from 1.41±0.04 to 0.89±0.02. The total fat content of the fillets decreased considerably from 4.7±0.6% at the beginning to 2.4±0.4% and 0.7±0.2% after 45 and 120 days respectively. Fillet fatty acid composition was affected by the time of stocking in the extensive farm. In contrast to the reduction in C18:1n-9, C18:2n-6, total monounsaturated fatty acid and total n-6 percent values, an increase in the C20:5n-3, C22:6n-3, total polyunsaturated fatty acid and total n-3 percent values was observed. It was shown that while other finishing strategies for salmonids have some disadvantages, the extensive culture system seems to be a potentially useful tool for increasing the general quality of the end product.

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Objective
To evaluate, through two studies, the factor structure, inter-rater agreement, and test–retest and inter-rater reliability of the Sport Injury Rehabilitation Adherence Scale (SIRAS).

Design
Repeated measures design in both Study 1 (video evaluation) and Study 2 (clinical evaluation).

Setting
University department (Study 1) and outpatient physiotherapy department (Study 2).

Participants

Sixty physiotherapists and physiotherapy students in Study 1 and 45 patients undergoing physiotherapy treatment for a musculoskeletal injury in Study 2.

Intervention
In Study 1, participants rated the adherence of a simulated videotaped patient demonstrating high, moderate and low adherence during rehabilitation. In Study 2, two physiotherapists rated the adherence of patients at two consecutive rehabilitation sessions.

Main outcome measure
The SIRAS.

Results
In Study 1, principal components analysis confirmed a single factor for the SIRAS, and inter-rater agreement values ranged from 0.87 to 0.93. In Study 2, inter-rater and test–retest reliability coefficients ranged from 0.76 [95% confidence interval (CI) 0.54 to 0.83] to 0.89 (95% CI 0.79 to 0.95), and from 0.63 (95% CI 0.36–0.82) to 0.76 (95% CI 0.55–0.88), respectively.

Conclusion
The SIRAS is a reliable measure with high inter-rater agreement when used to evaluate clinic-based adherence to physiotherapy rehabilitation for musculoskeletal injury.

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A simple and sensitive HPLC method was developed to simultaneously determine CPT-11 and its major metabolite SN-38 in culture media and cell lysates. Camptothecin (CPT) was used as internal standard (I.S.). Compounds were eluted with acetonitrile–50 mM disodium hydrogen phosphate buffer containing 10 mM sodium 1-heptane-sulfonate, with the pH adjusted to 3.0 using 85% (w/v) orthophosphoric acid (27/73, v/v) by a Hyperclon ODS (C18) column (200 mm × 4.6 mm i.d.), with detection at excitation and emission wavelengths of 380 and 540 nm, respectively. The average extraction efficiencies were 96.9–108.3% for CPT-11 in culture media and 94.3–107.2% for CPT-11 in cell lysates; and 87.7–106.8% for SN-38 in culture media and 90.1–105.6% for SN-38 in cell lysates. Within- and between-day precision and accuracy varied from 0.1 to 10.3%. The limit of quantitation (precision and accuracy <20%) was 5.0 and 2.0 ng/ml for CPT-11 and 1.0 and 0.5 ng/ml for SN-38 in culture media and cell lysates, respectively. This method was successfully applied to quantitate the cellular accumulation and metabolism of CPT-11 and SN-38 in H4-II-E, a rat hepatoma cell line.

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Ultrafine ferrite grain sizes were produced in a 0.11C-1.6Mn-0.2Si steel by torsion testing isothermally at 675 °C after air cooling from 1250 °C. The ferrite was observed to form intragranularly beyond a von Mises equivalent tensile strain of approximately 0.7 to 0.8 and the number fraction of intragranular ferrite grains continued to increase as the strain level increased. Ferrite nucleated to form parallel and closely spaced linear arrays or “rafts” of many discrete ultrafine ferrite grains. It is shown that ferrite nucleates during deformation on defects developed within the austenite parallel to the macroscopic shear direction (i.e., dynamic strain-induced transformation). A model austenitic Ni-30Fe alloy was used to study the substructure developed in the austenite under similar test conditions as that used to induce intragranular ferrite in the steel. It is shown that the most prevalent features developed during testing are microbands. It is proposed that high-energy jogged regions surrounding intersecting microbands provide potential sites for ferrite nucleation at lower strains, while at higher strains, the walls of the microbands may also act as nucleation sites.

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Objectives To determine the benefits and risks of a non-steroidal anti-inflammatory drug (NSAID) as prophylaxis for ectopic bone formation in patients undergoing total hip replacement (or revision) surgery.
Design Double blind randomised placebo controlled clinical trial, stratified by treatment site and surgery (primary or revision).
Setting 20 orthopaedic surgery centres in Australia and New Zealand.
Participants 902 patients undergoing elective primary or revision total hip replacement surgery.
Intervention 14 days' treatment with ibuprofen (1200 mg daily) or matching placebo started within 24 hours of surgery.
Main outcome measures Changes in self reported hip pain and physical function 6 to 12 months after surgery (Western Ontario and McMaster University Arthritis index).
Results There were no significant differences between the groups for improvements in hip pain (mean difference -0.1, 95% confidence interval -0.4 to 0.2, P = 0.6) or physical function (-0.1, -0.4 to 0.2, P = 0.5), despite a decreased risk of ectopic bone formation (relative risk 0.69, 0.56 to 0.83) associated with ibuprofen. There was a significantly increased risk of major bleeding complications in the ibuprofen group during the admission period (2.09, 1.00 to 4.39).
Conclusions
These data do not support the use of routine prophylaxis with NSAIDs in patients undergoing total hip replacement surgery.
Trial registration NCT00145730.

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Observers judged TTC with computer-generated displays simulating an approaching object in three familiar-size conditions:

(i) Real-size (smaller, larger objects depicted as tennis, soccer balls respectively).
(ii) Off-size (smaller, larger objects depicted as soccer, tennis balls respectively).
(iii) Ambiguous-size (smaller, larger objects depicted as texture-less black balls of different size).

Displays simulated objects approaching observersí viewpoint from 24.96 m, and disappearing at 5.76 m. Manipulation of approach velocities (4.8-19.2 msec-1) produced viewing times from 1.0 to 4.0 sec, and delays between object disappearance and tau-based TTC ranging from 0.3 to 1.2 sec. Motion characteristics of smaller and larger objects in the three familiar-size conditions simulated those of approaching real-sized tennis and soccer balls respectively; that is, for each approach velocity, tau‚-based TTC was the same across the three conditions for smaller and larger objects.

Results showed that, consistent with the proposition of tau-determined TTC, TTC estimates in the real-size condition were uninfluenced by object size. This is contrary to previous reports that TTC for larger objects is underestimated relative to TTC for smaller objects. However, such size-dependent TTC differences were found in the ambiguous-size condition, with even larger differences in the off-size condition; TTCs for the ëlargerí tennis ball were much less than TTCs to the ësmallerí soccer ball compared to corresponding TTCs in the ambiguous-size condition. These results are problematic for the proposition that tau solely determines TTC. We discuss the role of perceptual learning in resolving this problem.

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PURPOSE
We asked: 1) is statural growth inhibited in non-elite competitive female gymnasts?; and 2) if growth is reduced, is the effect similar for legs and spine?

METHODS
Height(Ht), sitting height(StHt) and leg length(LL) were measured in gymnasts and controls at baseline and every 12 mths for 2 yrs. Pubertal status was assessed by Tanner stage. Gymnasts were from USGF levels 4–10 and trained 7.5 to 22.5 hrs/wk. Age-adjusted Z-scores were determined for gymnasts on the anthropometric measures and based on linear regression analyses of data for 45 controls.

RESULTS
At baseline, pre-(N=40), peri-(N=16) and post-pubertal(N=11) gymnasts were shorter than controls(-0.9 to -1.3 SD, p < 0.01). In pre- and peri-pubertal gymnasts, this was due to a reduction in StHt (-0.8 to -1.3 SD) and LL (-0.8 to -1.1 SD)(p < 0.01). In post-pubertal gymnasts, StHt (-0.8 SD) was reduced (p < 0.05). No differences were observed in z-score deficits between pubertal groups, nor were there any differences in StHt and LL deficits. During 12 mths follow-up in 39 gymnasts, deficits in Ht z-scores were reduced further in pre-pubertal gymnasts (-0.2 SD, p < 0.001) due to a greater increase in the deficit in LL (-0.3 SD, p < 0.001). While the magnitude of z-score deficits for peri-pubertal gymnasts remained unchanged, Ht z-scores improved in post-pubertal gymnasts(+0.2SD, p < 0.05) due primarily to an increase in StHt (+0.4 SD, p < 0.01). Similar results were found in 16 gymnasts followed for 2 yrs.

CONCLUSION
Although small size may relate to self-selection for gymnastics, some non-elite female gymnasts may experience attenuated growth during early puberty due mainly to reduced leg growth. The increased growth observed in post-pubertal gymnasts is consistent with catch-up growth associated with delayed maturation.

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Objective To evaluate the effectiveness of a decision aid for prenatal testing of fetal abnormalities compared with a pamphlet in supporting women's decision making.
Design A cluster randomised controlled trial.
Setting Primary health care.
Population Women in early pregnancy consulting a GP.
Methods GPs were randomised to provide women with either a decision aid or a pamphlet. The decision aid was a 24-page booklet designed using the Ottowa Decision Framework. The pamphlet was an existing resource available in the trial setting.
Main outcome measures Validated scales were used to measure the primary outcomes, informed choice and decisional conflict, and the secondary outcomes, anxiety, depression, attitudes to the pregnancy/fetus and acceptability of the resource. Outcomes were measured at 14 weeks of gestation from questionnaires that women completed and returned by post.
Findings Women in the intervention group were more likely to make an informed decision 76% (126/165) than those in the control group 65% (107/165) (adjusted OR 2.08; 95% CI 1.14–3.81). A greater proportion of women in the intervention group 88% (147/167) had a 'good' level of knowledge than those in the control group 72% (123/171) (adjusted OR 3.43; 95% CI 1.79–6.58). Mean (SD) decisional conflict scores were low in both groups, decision aid 1.71 (0.49), pamphlet 1.65 (0.55) (adjusted mean difference 0.10; 95% CI −0.02 to 0.22). There was no strong evidence of differences between the trial arms in the measures of psychological or acceptability outcomes.
Conclusion A tailored prenatal testing decision aid plays an important role in improving women's knowledge of first and second trimester screening tests and assisting them to make decisions about screening and diagnostic tests that are consistent with their values.

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Objective: To evaluate the effectiveness of a patient education programme for preventing falls in the subacute hospital setting.

Design: Randomized controlled trial, subgroup analysis.

Participants: Patients of a metropolitan subacute/aged rehabilitation hospital who were recommended for a patient education intervention for the prevention of falls when enrolled in a larger randomized controlled trial of a falls prevention programme.

Methods: Participants in both the control and intervention groups who were recommended for the education programme intervention were followed for the duration of their hospital stay to determine if falls occurred. Only participants in the intervention group who were recommended for this intervention actually received it. In addition, these participants completed an evaluation survey at the completion of their education programme.

Results:
Intervention group participants in this subgroup analysis had a significantly lower incidence of falls than their control group counterparts (control: 16.0 falls/1000 participant-days, intervention: 8.2 falls/1000 participant-days, log-rank test: P = 0.007). However the difference in the proportion of fallers was not significant (relative risk 1.21, 95% confidence interval 0.68 to 2.14).

Conclusion:
Patient education is an important part of a multiple intervention falls prevention approach for the subacute hospital setting.

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Introduction: Obesity is thought to be a protective factor for bones in adults but not in children based on the evidence of the greater incidence of forearm fractures in obese children. Our objective was to investigate the effect of adiposity on bone strength in relation to the mechanical challenge placed onto the forearm bones in case of a fall.

Methods: Cross sectional areas (CSA) were obtained at the mid- and distal radius by peripheral quantitative computed tomography in 486 children (241 boys), mean age 8.3 years (range 6.9–9.7), participating in the LOOK Project. The following parameters were measured: bone mass and bone CSA (both sites), and muscle and fat CSA (mid-forearm only). Bone strength indices combining bone size and total volumetric density were calculated at each site.

Results/Discussion: Overweight children (BMI > percentile equivalent to 25 kg/m2 in adults) have higher bone parameters than normal-weight peers (Z-scores +0.6 to +0.9SD, p < 0.0001). These differences disappear after adjustment for muscle CSA. Adiposity (fat CSA/muscle CSA) was negatively correlated with bone mass, size and strength at the distal radius only (r = −0.1, p < 0.05). After adjustment for body weight (estimate of the load during a fall), the negative correlations were stronger and observed at both the mid- and distal radius (r = −0.37 to −0.55, p < 0.0001).

Conclusion. Overweight children have stronger bones due to greater muscle size. However, children with high fat mass relative to muscle mass (increased adiposity) have poorer bone strength, independent of weight, which may contribute to the increased risk of fracture in obese children.

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Background
The atopic march hypothesis suggests that infants with eczema are at increased risk of asthma. Others argue that eczema is not a risk factor for asthma unless there is also sensitization or early wheezing.
Objective
To examine the role of infantile eczema as a predictor of risk of childhood asthma, while allowing for the effects of early wheeze, sensitization, and sex, both as independent effects and possible effect modifiers.
Methods
A total of 620 infants with a family history of allergic disease was recruited. Eczema and wheeze was prospectively documented to 2 years of age. Sensitization was determined by skin prick tests at 6, 12, and 24 months to 6 common food and inhalant allergens. Interviews were conducted at 6 and 7 years to ascertain current asthma.
Results
Sufficiently complete data were available for 403 children. Eczema within the first 2 years of life was clearly associated with an increased risk of childhood asthma in boys (adjusted odds ratio, 2.45; 95% CI, 1.31-4.46) but not in girls (odds ratio, 0.88; 95% CI, 0.43-1.77; P for interaction = .031) even with adjustment for the effects of early allergic sensitization and wheeze. If these relationships are causal, an intervention to prevent eczema in boys might reduce the incidence of childhood asthma by as much as 28%.
Conclusion
Eczema in the first 2 years of life is associated with an increased risk of childhood asthma in boys, but there is no evidence of this in girls.

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Objective : Children's physical activity levels are difficult to establish on a day-to-day or season-to-season basis. Most studies have attempted to measure reliability in habitual settings. This study investigated the variability in children's physical activity during recess.

Methods :
Fifteen boys and 19 girls (aged 6 to 11 years) from 2 schools in North West England wore heart rate monitors for 5 consecutive days in summer and winter terms to assess day-to-day and seasonal variability during school recess. Data were collected in 2004. Repeated measures ANOVA's and intraclass correlations (ICC) analysed the day-to-day and seasonal variability in children's moderate-to-vigorous (MVPA) and vigorous physical activity (VPA) data.

Results : There were no significant differences in children's MVPA and VPA across days and seasons. ICCs for MVPA across 2 days ranged from 0.75 to 0.85 in summer, and from 0.53 to 0.81 in winter. Three-day MVPA ICCs were 0.83 in summer and 0.71 in winter.

Conclusions : The results revealed no significant variation in children's recess physical activity levels across days and seasons. Whilst children were free to choose their recess activities in school, the results suggested that children were relatively consistent in their choices, limiting physical activity variability.