149 resultados para Grain weight


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Objective: To determine solar load-bearing structures in the feet of feral horses and investigate morphological characteristics of the sole in feral horses and domestic Thoroughbreds. Sample: Forelimbs from cadavers of 70 feral horses and 20 domestic Thoroughbreds in Australia. Procedures: Left forefeet were obtained from 3 feral horse populations from habitats of soft substrate (SS [n = 10 horses]), hard substrate (HS [10]), and a combination of SS and HS (10) and loaded in vitro. Pressure distribution was measured with a pressure plate. Sole depth was measured at 12 points across the solar plane in feet obtained from feral horses from SS (n = 20 horses) and HS (20) habitats and domestic Thoroughbreds (20). Results: Feet of feral horses from HS habitats loaded the periphery of the sole and hoof wall on a flat surface. Feral horses from HS or SS habitats had greater mean sole depth than did domestic Thoroughbreds. Sole depth was greatest peripherally and was correlated with the loading pattern. Conclusions and Clinical Relevance: The peripheral aspect of the sole in the feet of feral horses had a load-bearing function. Because of the robust nature of the tissue architecture, the hoof capsule of feral horses may be less flexible than that of typical domestic horses. The application of narrow-web horseshoes may not take full advantage of the load-bearing and force-dissipating properties of the peripheral aspect of the sole. Further studies are required to understand the effects of biomechanical stimulation on the adaptive responses of equine feet.

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To ensure better concrete quality and long-term durability, there has been an increasing focus in recent years on the development of test methods for quality control of concrete. This paper presents a study to evaluate the effect of water accessible porosity and oven-dry unit weight on the resistance of concrete to chloride-ion penetration. Based on the experimental results and regression analyses, empirical relationships of the charge passed (ASTM C 1202) and chloride migration coefficient (NT Build 492) versus the water accessible porosity and oven dry unit weight of the concrete are established. Using basic physical properties of water accessible porosity and oven dry unit weight which can be easily determined, total charge passed and migration coefficient of the concrete can be estimated for quality control and for estimating durability of concrete.

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The presence of insect pests in grain storages throughout the supply chain is a significant problem for farmers, grain handlers, and distributors world-wide. Insect monitoring and sampling programmes are used in the stored grains industry for the detection and estimation of pest populations. At the low pest densities dictated by economic and commercial requirements, the accuracy of both detection and abundance estimates can be influenced by variations in the spatial structure of pest populations over short distances. Geostatistical analysis of Rhyzopertha dominica populations in 2 and 3 dimensions showed that insect numbers were positively correlated over short (0.5 cm) distances, and negatively correlated over longer (.10 cm) distances. At 35 C, insects were located significantly further from the grain surface than at 25 and 30 C. Dispersion metrics showed statistically significant aggregation in all cases. The observed heterogeneous spatial distribution of R. dominica may also be influenced by factors such as the site of initial infestation and disturbance during handling. To account for these additional factors, I significantly extended a simulation model that incorporates both pest growth and movement through a typical stored-grain supply chain. By incorporating the effects of abundance, initial infestation site, grain handling, and treatment on pest spatial distribution, I developed a supply chain model incorporating estimates of pest spatial distribution. This was used to examine several scenarios representative of grain movement through a supply chain, and determine the influence of infestation location and grain disturbance on the sampling intensity required to detect pest infestations at various infestation rates. This study has investigated the effects of temperature, infestation point, and grain handling on the spatial distribution and detection of R. dominica. The proportion of grain infested was found to be dependent upon abundance, initial pest location, and grain handling. Simulation modelling indicated that accounting for these factors when developing sampling strategies for stored grain has the potential to significantly reduce sampling costs while simultaneously improving detection rate, resulting in reduced storage and pest management cost while improving grain quality.

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We estimated the heritability and correlations between body and carcass weight traits in a cultured stock of giant freshwater prawn (GFP) (Macrobrachium rosenbergii) selected for harvest body weight in Vietnam. The data set consisted of 18,387 body and 1,730 carcass records, as well as full pedigree information collected over four generations. Variance and covariance components were estimated by restricted maximum likelihood fitting a multi-trait animal model. Across generations, estimates of heritability for body and carcass weight traits were moderate and ranged from 0.14 to 0.19 and 0.17 to 0.21, respectively. Body trait heritabilities estimated for females were significantly higher than for males whereas carcass weight trait heritabilities estimated for females and males were not significantly different (P>. 0.05). Maternal effects for body traits accounted for 4 to 5% of the total variance and were greater in females than in males. Genetic correlations among body traits were generally high in the mixed sexes. Genetic correlations between body and carcass weight traits were also high. Although some issues remain regarding the best statistical model to be fitted to GFP data, our results suggest that selection for high harvest body weight based on breeding values estimated by fitting an animal model to the data can significantly improve mean body and carcass weight in GFP.

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We estimated genetic changes in body and carcass weight traits in a giant freshwater prawn (GFP) (Macrobrachium rosenbergii) population selected for increased body weight at harvest in Vietnam. The data set consisted of 18,387 individual body and 1730 carcass weight records, as well as full pedigree information collected over four generations. Average selection response (per generation) in body weight at harvest (transformed to square root) estimated as the difference between the Selection line and the Control group was 7.4% calculated from least squares mean (LSMs), 7.0% from estimated breeding values (EBVs) and 4.4% calculated from EBVs between two consecutive generations. Favorable correlated selection responses (estimated from LSMs) were found for other body traits including: total length, cephalothorax length, abdominal length, cephalothorax width, and abdominal width (12.1%, 14.5%, 10.4%, 15.5% and 13.3% over three selection generations, respectively). Data in the second generation of selection showed positive correlated responses for carcass weight traits including: abdominal weight, exoskeleton-off weight, and telson-off weight of 8.8%, 8.6% and 8.8%, respectively. We conclude that body weight at harvest responded well to the application of combined (between and within) family selection and correlated responses in carcass weight traits were favorable.

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BACKGROUND/OBJECTIVE: To investigate the extent of baseline psychosocial characterisation of subjects in published dietary randomised controlled trials (RCTs) for weight loss. SUBJECTS/METHODS: Systematic review of adequately sized (nX10) RCTs comprising X1 diet-alone arm for weight loss were included for this systematic review. More specifically, trials included overweight (body mass index 425 kg/m2) adults, were of duration X8 weeks and had body weight as the primary outcome. Exclusion criteria included specific psychological intervention (for example, Cognitive Behaviour Therapy (CBT)), use of web-based tools, use of supplements, liquid diets, replacement meals and very-low calorie diets. Physical activity intervention was restricted to general exercise only (not supervised or prescribed, for example, VO2 maximum level). RESULTS: Of 176 weight-loss RCTs published during 2008–2010, 15 met selection criteria and were assessed for reported psychological characterisation of subjects. All studies reported standard characterisation of clinical and biochemical characteristics of subjects. Eleven studies reported no psychological attributes of subjects (three of these did exclude those taking psychoactive medication). Three studies collected data on particular aspects of psychology related to specific research objectives (figure scale rating, satiety and quality-of-life). Only one study provided a comprehensive background on psychological attributes of subjects. CONCLUSION: Better characterisation in behaviour-change interventions will reduce potential confounding and enhance generalisability of such studies.

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The growth of suitable tissue to replace natural blood vessels requires a degradable scaffold material that is processable into porous structures with appropriate mechanical and cell growth properties. This study investigates the fabrication of degradable, crosslinkable prepolymers of l-lactide-co-trimethylene carbonate into porous scaffolds by electrospinning. After crosslinking by γ-radiation, dimensionally stable scaffolds were obtained with up to 56% trimethylene carbonate incorporation. The fibrous mats showed Young’s moduli closely matching human arteries (0.4–0.8 MPa). Repeated cyclic extension yielded negligible change in mechanical properties, demonstrating the potential for use under dynamic physiological conditions. The scaffolds remained elastic and resilient at 30% strain after 84 days of degradation in phosphate buffer, while the modulus and ultimate stress and strain progressively decreased. The electrospun mats are mechanically superior to solid films of the same materials. In vitro, human mesenchymal stem cells adhered to and readily proliferated on the three-dimensional fiber network, demonstrating that these polymers may find use in growing artificial blood vessels in vivo.

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The University of Queensland UltraCommuter concept is an ultra- light, low-drag, hybrid-electric sports coupe designed to minimize energy consumption and environmental impact while enhancing the performance, styling, features and convenience that motorists enjoy. This paper presents a detailed simulation study of the vehicle's performance and fuel economy using ADVISOR, including a detailed description of the component models and parameters assumed. Results from the study include predictions of a 0-100 kph acceleration time of ≺9s, and top speed of 170 kph, an electrical energy consumption of ≺67 Wh/km in ZEV mode and a petrol-equivalent fuel consumption of ≺2.5 L/100 km in charge-sustaining HEV mode. Overall, the results of the ADVISOR modelling confirm the UltraCommuter's potential to achieve high performance with high efficiency, and the authors look forward to a confirmation of these estimates following completion of the vehicle.

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Background & aims Depression has a complex association with cardiometabolic risk, both directly as an independent factor and indirectly through mediating effects on other risk factors such as BMI, diet, physical activity, and smoking. Since changes to many cardiometabolic risk factors involve behaviour change, the rise in depression prevalence as a major global health issue may present further challenges to long-term behaviour change to reduce such risk. This study investigated associations between depression scores and participation in a community-based weight management intervention trial. Methods A group of 64 overweight (BMI > 27), otherwise healthy adults, were recruited and randomised to follow either their usual diet, or an isocaloric diet in which saturated fat was replaced with monounsaturated fat (MUFA), to a target of 50% total fat, by adding macadamia nuts to the diet. Subjects were assessed for depressive symptoms at baseline and at ten weeks using the Beck Depression Inventory (BDI-II). Both control and intervention groups received advice on National Guidelines for Physical Activity and adhered to the same protocol for food diary completion and trial consultations. Anthropometric and clinical measurements (cholesterol, inflammatory mediators) also were taken at baseline and 10 weeks. Results During the recruitment phase, pre-existing diagnosed major depression was one of a range of reasons for initial exclusion of volunteers from the trial. Amongst enrolled participants, there was a significant correlation (R = −0.38, p < 0.05) between BDI-II scores at baseline and duration of participation in the trial. Subjects with a baseline BDI ≥10 (moderate to severe depression symptoms) were more likely to dropout of the trial before week 10 (p < 0.001). BDI-II scores in the intervention (MUFA) diet group decreased, but increased in the control group over the 10-week period. Univariate analysis of variance confirmed these observations (adjusted R2 = 0.257, p = 0.01). Body weight remained static over the 10-week period in the intervention group, corresponding to a relative increase in the control group (adjusted R2 = 0.097, p = 0.064). Conclusions Depression symptoms have the potential to affect enrolment in and adherence to dietbased risk reduction interventions, and may consequently influence the generalisability of such trials. Depression scores may therefore be useful for characterising, screening and allocating subjects to appropriate treatment pathways.

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A qualitative analysis of the expected dilatation strain field in the vicinity of an array of grain-boundary (GB) dislocations is presented. The analysis provides a basis for the prediction of the critical current densities (jc) across low-angle YBa2Cu3O7- (YBCO) GBs as a function of their energy. The introduction of the GB energy allows the extension of the analysis to high-angle GBs using established models which predict the GB energy as a function of misorientation angle. The results are compared to published data for jc across [001]-tilt YBCO GBs for the full range of misorientations, showing a good fit. Since the GB energy is directly related to the GB structure, the analysis may allow a generalization of the scaling behavior of jc with the GB energy. © 1995 The American Physical Society.

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The microstructure of an artificial grain boundary in an YBa2Cu3O7-δ (YBCO) thin film grown on a (100)(110), [001]-tilt yttria-stabilized-zirconia (YSZ) bicrystal substrate has been studied using transmission electron microscopy (TEM). The orientation relationship between the YBCO film and the YSZ substrate was [001]YBCO∥[001]YSZ and [110]YBCO∥[100]YSZ for each half of the bicrystal film. However, the exact boundary geometry of the bicrystal substrate was not transferred to the film. The substrate boundary was straight while the film boundary was wavy. In several cases there was bending of the lattice confined within a distance of a few basal-plane lattice spacings from the boundary plane and microfaceting. No intergranular secondary phase was observed but about 25% of the boundary was covered by c-axis-tilted YBCO grains and a-axis-oriented grains, both of which were typically adjacent to CuO grains or surrounded by a thin Cu-rich amorphous layer.

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The microstructure of artificial grain boundaries in YBa2Cu3O7-δ (YBCO) thin films grown on [001] tilt YZrO2 (YSZ) bicrystal substrates has been characterized using transmission electron microscopy and atomic force microscopy. Despite a relatively straight morphology of the substrate boundaries, the film boundaries were wavy. The waviness was a result of the combined effects of grooving at the substrate boundaries prior to the film deposition and an island-growth mechanism for YBCO on YSZ substrates. The dihedral angle of the groove walls varied with the misorientation angle and depended on the symmetry of the substrate boundary. The amplitudes of the film boundary waviness compared well with the widths of the grooves. In addition, the grooves induced local bending of the YBCO lattice planes and additional tilt components perpendicular to the c-axis close to the film boundaries. © 1995.

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Weak links were fabricated by pulsed laser deposition of YBa 2Cu3Ox thin films on Y-ZrO2 bicrystal substrates. They were formed by transferring the bicrystal boundary into the epitaxial film during the film growth. Their properties were determined by the misorientation angle ( theta ) between the two halves of the bicrystal. The transport properties of the weak links were studied as a function of theta and an exponential dependence of the weak link critical current density was observed for angles up to 45 degrees . Clear Josephson effects with good microwave and magnetic field response were observed.

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We have studied weak links and dc-SQUIDs made from pulsed laser deposited YBa2Cu3O7-δ thin films on Y-ZrO 2 bicrystal substrates. The transport properties of the weak links were studied as a function of the misorientation angle (θ) between the two halves of the bicrystal and an exponential dependence of the weak link critical current density was observed for angles up to 40°at 77 K. Josephson effects with clear microwave and magnetic field responses were observed. An optimum dc-SQUID performance at 77 K was obtained for θ=32°. At this temperature, we achieved a periodic magnetic field response with a modulation depth of 12 μV.

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Engineered grain boundary Josephson junctions in YBaCuO were formed on bicrystal Y-ZrO2 substrates. Laser deposited films were patterned into micron size microbridges. The authors obsd. a pronounced correlation between superconducting transport properties of grain boundary junctions and the misorientation angle θ between the two halves of the bicrystal. The crit. Josephson current Ic decreased about four orders of magnitude as θ was increased from 0 to 45 degrees. Clear microwave and magnetic field responses were obsd. at 77 K. At this temp., crit. current times normal resistance products, IcRn, of up to 1 mV were measured for low angle grain boundaries, and Shapiro steps were obsd. up to that voltage. DC SQUIDs were fabricated, and best performance at 77 K was obtained for θ = 32° with a 4-μm strip width. To utilize the higher IcRn value of a lower θ, submicron junctions have to be developed. [on SciFinder(R)]