17 resultados para control volume

em Deakin Research Online - Australia


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Background: 'MRI negative PET positive temporal lobe epilepsy' represents a substantial minority of temporal lobe epilepsy (TLE). Clinicopathological and qualitative imaging differences from mesial temporal lobe epilepsy are reported. We aimed to compare TLE with hippocampal sclerosis (HS+ve) and non lesional TLE without HS (HS-ve) on MRI, with respect to quantitative FDG-PET and MRI measures.

Methods: 30 consecutive HS-ve patients with well-lateralised EEG were compared with 30 age- and sex-matched HS+ve patients with well-lateralised EEG. Cerebral, cortical lobar and hippocampal volumetric and co-registered FDG-PET metabolic analyses were performed.

Results: There was no difference in whole brain, cerebral or cerebral cortical volumes. Both groups showed marginally smaller cerebral volumes ipsilateral to epileptogenic side (HS-ve 0.99, p = 0.02, HS+ve 0.98, p < 0.001). In HS+ve, the ratio of epileptogenic cerebrum to whole brain volume was less (p = 0.02); the ratio of epileptogenic cerebral cortex to whole brain in the HS+ve group approached significance (p = 0.06). Relative volume deficits were seen in HS+ve in insular and temporal lobes. Both groups showed marked ipsilateral hypometabolism (p < 0.001), most marked in temporal cortex. Mean hypointensity was more marked in epileptogenic-to-contralateral hippocampus in HS+ve (ratio: 0.86 vs 0.95, p < 0.001). The mean FDG-PET ratio of ipsilateral to contralateral cerebral cortex however was low in both groups (ratio: HS-ve 0.97, p < 0.0001; HS+ve 0.98, p = 0.003), and more marked in HS-ve across all lobes except insula.

Conclusion: Overall, HS+ve patients showed more hippocampal, but also marginally more ipsilateral cerebral and cerebrocortical atrophy, greater ipsilateral hippocampal hypometabolism but similar ipsilateral cerebral cortical hypometabolism, confirming structural and functional differences between these groups.

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OBJECTIVE—To examine whether improvements in glycemic control and body composition resulting from 6 months of supervised high-intensity progressive resistance training could be maintained after an additional 6 months of home-based resistance training.

RESEARCH DESIGN AND METHODS—We performed a 12-month randomized controlled trial in 36 sedentary, overweight men and women with type 2 diabetes (aged 60–80 years) who were randomly assigned to moderate weight loss plus high-intensity progressive resistance training (RT&WL group) or moderate weight loss plus a control program (WL group). Supervised gymnasium-based training for 6 months was followed by an additional 6 months of home-based training. Glycemic control (HbA1c), body composition, muscle strength, and metabolic syndrome abnormalities were assessed at 0, 3, 6, 9, and 12 months.

RESULTS—Compared with the WL group, HbA1c decreased significantly more in the RT&WL group (–0.8%) during 6 months of supervised gymnasium-based training; however, this effect was not maintained after an additional 6 months of home-based training. In contrast, the greater increase in lean body mass (LBM) observed in the RT&WL group compared with the WL group (0.9 kg, P < 0.05) after the gymnasium-based training tended to be maintained after the home-based training (0.8 kg, P = 0.08). Similarly, the gymnasium-based increases in upper body and lower body muscle strength in the RT&WL group were maintained over the 12 months (P < 0.001). There were no between-group differences for changes in body weight, fat mass, fasting glucose, or insulin at 6 or 12 months.

CONCLUSIONS—In older adults with type 2 diabetes, home-based progressive resistance training was effective for maintaining the gymnasium-based improvements in muscle strength and LBM but not glycemic control. Reductions in adherence and exercise training volume and intensity seem to impede the effectiveness of home-based training for maintaining improved glycemic control.


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This second volume presents the data from the 2005 and 2007 rounds of the Corio and Norlane Neighbourhood Renewal Community Surveys. The focus of this report is on change in the responses of participants between the two time periods. All of the data presented has been previously provided – in the 2005 report, and the 2007 data in the first volume of the current report. The comparison tables are presented separately for the NRA participants and for the control group participants.

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This second volume presents the data from the 2004 and 2007 rounds of the Colac Neighbourhood Renewal Community Surveys. The focus of this report is on change in the responses of participants between the two time periods. All of the data presented has been previously provided – in the 2004 report, and the 2007 data in the first volume of the current report. The comparison tables are presented separately for the NRA participants and for the control group participants. The control group sample was stratified according to the SEIFA classification system. Data from the lowest 3 SEIFA deciles and the highest three SEIFA deciles are utilized in the report to provide some indication of differences in responses between participants of most to least disadvantage within the control group

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Environmental pollutants which alter endocrine function are now known to decrease vertebrate reproductive success. There is considerable evidence for endocrine disruption from aquatic ecosystems, but knowledge is lacking with regard to the interface between terrestrial and aquatic ecosystems. Here, we show for the first time that birds foraging on invertebrates contaminated with environmental pollutants, show marked changes in both brain and behaviour. We found that male European starlings (Sturnus vulgaris) exposed to environmentally relevant levels of synthetic and natural estrogen mimics developed longer and more complex songs compared to control males, a sexually selected trait important in attracting females for reproduction. Moreover, females preferred the song of males which had higher pollutant exposure, despite the fact that experimentally dosed males showed reduced immune function. We also show that the key brain area controlling male song complexity (HVC) is significantly enlarged in the contaminated birds. This is the first evidence that environmental pollutants not only affect, but paradoxically enhance a signal of male quality such as song. Our data suggest that female starlings would bias their choice towards exposed males, with possible consequences at the population level. As the starling is a migratory species, our results suggest that transglobal effects of pollutants on terrestrial vertebrate physiology and reproduction could occur in birds.

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Songbirds sing complex songs as a result of evolution through sexual selection. The evolution of such sexually selected traits requires genetic control, as well as selection on their expression. Song is controlled by a discrete neural pathway in the brain, and song complexity has been shown to correlate with the volume of specific song control nuclei. As such, the development of these nuclei, in particular the high vocal centre (HVC), is thought to be the mechanism controlling signal expression indicating male quality. We tested the hypothesis that early developmental stress selectively affects adult HVC size, compared with other brain nuclei. We did this by raising cross–fostered zebra finches (Taeniopygia guttata) under stressed and controlled conditions and determining the effect on adult HVC size. Our results confirm the strong influence of environmental conditions, particularly on HVC development, and therefore on the expression of complex songs. The results also show that both environmental and genetic factors affect the development of several brain nuclei, highlighting the developmental plasticity of the songbird brain. In all, these results explain how the complex song repertoires of songbirds can evolve as honest indicators of male quality.

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This study aimed at demonstrating the asymmetry in volume between the dominant and nondominant upper limbs in tennis players, controlled for maturity status. Upper limb volumes on both sides were calculated in 72 tennis players and 84 control subjects, using the truncated cone method. The participants’ maturity status was determined using the predicted age at peak height velocity (PHV). The results showed significant larger side-to-side asymmetry in volume in tennis groups than
in control groups. These findings suggested that, even before PHV, specific-sport adaptations occurred in the dominant upper limb in tennis players.

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Low-volume ‘sprint’ interval training (SIT) stimulates rapid improvements in muscle oxidative capacity that are comparable to levels reached following traditional endurance training (ET) but no study has examined metabolic adaptations during exercise after these different training strategies. We hypothesized that SIT and ET would induce similar adaptations in markers of skeletal muscle carbohydrate (CHO) and lipid metabolism and metabolic control during exercise despite large differences in training volume and time commitment. Active but untrained subjects (23 ± 1 years) performed a constant-load cycling challenge (1 h at 65% of peak oxygen uptake before and after 6 weeks of either SIT or ET (n = 5 men and 5 women per group). SIT consisted of four to six repeats of a 30 s ‘all out’ Wingate Test (mean power output ∼500 W) with 4.5 min recovery between repeats, 3 days per week. ET consisted of 40–60 min of continuous cycling at a workload that elicited ∼65% (mean power output ∼150 W) per day, 5 days per week. Weekly time commitment (∼1.5 versus ∼4.5 h) and total training volume (∼225 versus ∼2250 kJ week−1) were substantially lower in SIT versus ET. Despite these differences, both protocols induced similar increases (P < 0.05) in mitochondrial markers for skeletal muscle CHO (pyruvate dehydrogenase E1α protein content) and lipid oxidation (3-hydroxyacyl CoA dehydrogenase maximal activity) and protein content of peroxisome proliferator-activated receptor-γ coactivator-1α. Glycogen and phosphocreatine utilization during exercise were reduced after training, and calculated rates of whole-body CHO and lipid oxidation were decreased and increased, respectively, with no differences between groups (all main effects, P < 0.05). Given the markedly lower training volume in the SIT group, these data suggest that high-intensity interval training is a time-efficient strategy to increase skeletal muscle oxidative capacity and induce specific metabolic adaptations during exercise that are comparable to traditional ET.

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BACKGROUND: The IPAA has become established as the preferred technique for restoring intestinal continuity postproctocolectomy. The ideal pouch design has not been established. W-pouches may give better functional results owing to increased volume, whereas the J-pouch’s advantage is its straightforward construction. We report short- and long-term results of an randomized control trial designed to establish the ideal pouch.

DESIGN: Ninety-four patients were randomly assigned to J- and W-pouches (49:45) and assessed at 1 and 8.7 years postoperatively. Assessment was questionnaire based and designed to assess pouch function and patient quality of life.

RESULTS: Eighty-five percent of patients were followed up at 1 year, and 68% were followed up at 8.7 years. At 1 year, there was a significant difference in 24-hour bowel movement frequency J- vs W-pouches 7 vs 5(p < 0.001) and in daytime frequency J- vs W-pouches 6 vs 4 (p < 0.001), with no difference in nocturnal function. At 9-year follow-up, function had equilibrated between the 2 groups: 24-hour bowel movement frequency J- vs W-pouches 6.5 vs 6 (p = 0.36), daytime frequency 5.5 vs 5 (p = 0.233), and nocturnal function 1 vs 1 (p = 0.987). Mean operating time of J- and W-pouches was 195 and 215 minutes (p < 0.05). All other parameters, pad usage, urgency, incontinence, and quality of life, did not differ significantly between groups.

CONCLUSION: These data demonstrate that the theoretical functional advantage conferred on the W-pouch by its greater volume exists only in the short term and is of little consequence to patients’ long-term quality of life. This advantage is attenuated as the pouches mature, resulting in no disparity in pouch function. This, combined with the more consistent, efficient, and easily taught construction of the J-pouch, should conclusively establish it as the optimum ileal-pouch design.

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The rheological properties of a hierarchically structured supramolecular soft material are mainly determined by the structure of its network. Controlling the thermodynamic driving force of physical gels (one type of such materials) during the formation has proven effective in manipulating the network structure due to the nature of nucleation and growth of the fiber network formation in such a supramolecular soft material. Nevertheless, it is shown in this study that such a property can be dramatically influenced when the volume of the system is reduced to below a threshold value. Unlike un-confined systems, the network structure of such a soft material formed under volume confinement contains a constant network size, independent of the experimental conditions, i.e. temperature and solute concentration. This implies that the size of the fiber networks in such a material is invariable and free from the influence of external factors, once the volume is reduced to a threshold. The observations of this work are significant in the control of the formation of fibrous networks in materials of this type.

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Balance training is commonly used in the rehabilitation process of ankle injuries; however, the exercise prescription guidelines for prescribing balance training are poorly understood. The aim of the present study was to determine if high or low volume balance training is more effective in improving postural sway after an 8 week balance training program utilising the same exercises. Seventeen subjects (14 male, 3 female) with a mean age of 24.06 ± 5.6 years were randomly allocated into a control group (CG), low volume training (LVT) or high volume training (HVT). All subjects had sustained at least two inversion ankle injuries within the last 18 months. Subjects completed 8 weeks of balance training of up to 30 mins duration, 3 times per week. LVT consisted of 40 repetitions for week 1, progressing to 90 repetitions by week 8. HVT consisted of 60 repetitions for week 1, progressing to 130 repetitions by week 8. The maximum centre of pressure (COP) excursion was obtained from the porce plate in the medial-lateral (ML) direction and subsequently used for pre-test and post-test analysis. After the 8 week training intervention, there was a significant (P<0.001) difference in postural sway between pre and post testing for both the LVT (pre = 88.69mm ± 25.08mm, post = 72.17mm ± 27.53mm) and HVT (pre = 77.47mm ±10.57mm, post = 58.54mm ± 7.01mm) groups. There was no significant (P>0.01) difference detected for improvements between the LVT and HVT, however reported effect sizes (ES) showed large effect size chances in the high volume training (ES = 1.7) whereas low volume training showed medium effect sizes changes (ES = 0.6). This preliminary study demonstrates the importance of training volume in the rehabilitation of ankle injuries, with the HVT being superior to LVT.

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Among air-breathing divers, control of buoyancy through lung volume regulation may be most highly developed in marine turtles. In short, the turtle lung may serve a dual role as both an oxygen store and in buoyancy control. A simple model is developed to show that, for turtles diving up to the maximum depth at which they can still use their lungs to attain neutral buoyancy, the total oxygen store will increase greatly with dive depth, and hence a corresponding increase in dive duration is predicted. Time–depth recorders attached to free-living green turtles (Chelonia mydas) at Ascension Island confirmed a marked increase in dive duration with depth, with the gradient of this relationship being >10 times that seen in diving birds and mammals. Consistent with the prediction that the lungs serve a dual role, we found that, when lead weights were added to some turtles to increase their specific gravity, the mean depth of dives decreased, but for dives to the same depth, weighted animals dived for longer. The depth distribution of green turtles seems to be generally constrained by the maximum depth at which they can still attain close to neutral buoyancy.

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This paper presents design and fabrication of a microbioreactor platform, and implementation of two temperature control methods (i.e. on-off and PID) and their performance evaluation on the microbioreactor platform (working volume ~300 μL). The temperature of the microbioreactor content is controlled by using a subminiature heater placed underneath the microbioreactor and is measured with a miniature Pt 100 sensor. The microbioreactor is also integrated with a magnetic stirring capacity and a water evaporation control scheme. Programs for the two temperature control methods are written in LabVIEW software and implemented by interfacing them with a data acquisition card. It is shown that by implementing on–off and PID temperature control methods, the temperature of the microbioreactor content can be tightly controlled with an accuracy of approximately ±0.5 °C of the set point values. Both control methods also provide a good response and settling time values (i.e. around 2 min). Contrary to the on/off control method, the PID control method requires no adjustments whenever the set-point values are modified. The PID temperature control method works well for the entire tested range.

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Smart grid constrained optimal control is a complex issue due to the constant growth of grid complexity and the large volume of data available as input to smart device control. In this context, traditional centralized control paradigms may suffer in terms of the timeliness of optimization results due to the volume of data to be processed and the delayed asynchronous nature of the data transmission. To address these limits of centralized control, this paper presents a coordinated, distributed algorithm based on distributed, local controllers and a central coordinator for exchanging summarized global state information. The proposed model for exchanging global state information is resistant to fluctuations caused by the inherent interdependence between local controllers, and is robust to delays in information exchange. In addition, the algorithm features iterative refinement of local state estimations that is able to improve local controller ability to operate within network constraints. Application of the proposed coordinated, distributed algorithm through simulation shows its effectiveness in optimizing a global goal within a complex distribution system operating under constraints, while ensuring network operation stability under varying levels of information exchange delay, and with a range of network sizes.

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Driven by the ever-growing expectation of ubiquitous connectivity and the widespread adoption of IEEE 802.11 networks, it is not only highly demanded but also entirely possible for in-motion vehicles to establish convenient Internet access to roadside WiFi access points (APs) than ever before, which is referred to as Drive-Thru Internet. The performance of Drive-Thru Internet, however, would suffer from the high vehicle mobility, severe channel contentions, and instinct issues of the IEEE 802.11 MAC as it was originally designed for static scenarios. As an effort to address these problems, in this paper, we develop a unified analytical framework to evaluate the performance of Drive-Thru Internet, which can accommodate various vehicular traffic flow states, and to be compatible with IEEE 802.11a/b/g networks with a distributed coordination function (DCF). We first develop the mathematical analysis to evaluate the mean saturated throughput of vehicles and the transmitted data volume of a vehicle per drive-thru. We show that the throughput performance of Drive-Thru Internet can be enhanced by selecting an optimal transmission region within an AP's coverage for the coordinated medium sharing of all vehicles. We then develop a spatial access control management approach accordingly, which ensures the airtime fairness for medium sharing and boosts the throughput performance of Drive-Thru Internet in a practical, efficient, and distributed manner. Simulation results show that our optimal access control management approach can efficiently work in IEEE 802.11b and 802.11g networks. The maximal transmitted data volume per drive-thru can be enhanced by 113.1% and 59.5% for IEEE 802.11b and IEEE 802.11g networks with a DCF, respectively, compared with the normal IEEE 802.11 medium access with a DCF.