990 resultados para Pre - fabricated wall
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The aim of this study was to determine compliance with the National Association for Sport and Physical Education (NASPE) guideline for physical activity and American Academy of Pediatrics (AAP) recommendation for electronic media use among urban pre-school children in two large cities on the East Coast of Australia. Cross-sectional data were collected from 266 parents. Time spent using electronic media (watching television, DVDs or on the computer) and in physical activity were parent reported. The proportion who met each guideline was calculated. 56 per cent and 79% of children met the NASPE guideline on weekdays and weekends, respectively, while 73% and 70% met the AAP recommendation on weekdays and weekends, with no difference between boys and girls. A substantial minority do not meet physical activity and electronic media use recommendations, highlighting the need to better understand what factors contribute to physical activity and electronic media use among this group of pre-schoolers.
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Colonisation of the maternal uterine wall by the trophoblast involves a series of alterations in the behaviour and morphology of trophoblast cells. Villous cytotrophoblast cells change from a well-organised coherently layered phenotype to one that is extravillous, acquiring a proliferative, migratory and invasive capacity, to facilitate fetal-maternal interaction. These changes are similar to those of other developmental processes falling under the umbrella of an epithelial-mesenchymal transition (EMT). Modulation of cell adhesion and cell polarity occurs through changes in cell-cell junctional molecules, such as the cadherins. The cadherins, particularly the classical cadherins (e.g. Epithelial-(E)-cadherin), and their link to adaptors called catenins at cell-cell contacts, are important for maintaining cell attachment and the layered phenotype of the villous cytotrophoblast. In contrast, reduced expression and re-organization of cadherins from these cell junctional regions promote a loosened connection between cells, coupled with reduced apico-basal polarity. Certain non-classical cadherins play an active role in cell migration processes. In addition to the classical cadherins, two other cadherins which have been reported in placental tissues are vascular endothelial (VE) cadherin and cadherin-11. Cadherin molecules are well placed to be key regulators of trophoblast cell behaviour, analogous to their role in other developmental EMTs. This review addresses cadherin expression and function in normal and diseased human placental tissues, especially in fetal growth restriction and pre-eclampsia where trophoblast invasion is reduced.
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OBJECTIVE To compare the physical activity levels of overweight and non overweight 3- to 5-y-old children while attending preschool. A secondary aim was to evaluate weight-related differences in hypothesized parental determinants of child physical activity behavior. DESIGN: Cross-sectional study. SUBJECTS A total of 245, 3- to 5-y-olds (127 girls, 118 boys) and their parent(s) (242 mothers, 173 fathers) recruited from nine preschools. Overweight status determined using the age- and sex-specific 85th percentile for body mass index (BMI) from CDC Growth Charts. MEASUREMENTS Physical activity during the preschool day was assessed on multiple days via two independent objective measuresFdirect observation using the observation system for recording activity in preschools (OSRAP) and real-time accelerometry using the MTI/CSA 7164 accelerometer. Parents completed a take-home survey assessing sociodemographic information, parental height and weight, modeling of physical activity, support for physical activity, active toys and sporting equipment at home, child’s television watching, frequency of park visitation, and perceptions of child competence. RESULTS Overweight boys were significantly less active than their nonoverweight peers during the preschool day. No significant differences were observed in girls. Despite a strong association between childhood overweight status and parental obesity, no significant differences were observed for the hypothesized parental influences on physical activity behavior. CONCLUSIONS Our results suggest that a significant proportion of overweight children may be at increased risk for further gains in adiposity because of low levels of physical activity during the preschool day.
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This thesis studied the emotional climate (EC) of a pre-service science teachers' class in Bhutan. It examined the types of activities students engaged in and the relationship between the tutor and students whose interactions produced both positive and negative EC in the class. The major finding was that the activities involving students' presentations using video clips and models, group activity, and coteaching valenced the class EC positively. Negative EC was identified when the tutor ignored students' responses, during formal lectures, and when the tutor was uncertain of the subject knowledge. The replication of activities that produce positive EC by other Bhutanese tutors may improve the standard of science education in the country.
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It is demonstrated that a magnetic field has a profound effect on the length of a single-wall carbon nanotube (SWCNT) synthesized in the arc discharge. The average length of SWCNT increases by a factor of 2 in discharge with magnetic field as compared with the discharge without magnetic field, and the yield of long nanotubes with lengths above 5 μm also increases. A model of SWCNT growth on metal catalyst in arc plasma was developed. Monte-Carlo simulations confirm that the increase of the plasma density in the magnetic field leads to an increase in the nanotube growth rate and thus leads to longer nanotubes.
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Titanium dioxide thin films with a rutile crystallinite size around 20 nm were fabricated by pulsed laser deposition (PLD) aided with an electron cyclotron resonance (ECR) plasma. With annealing treatment, the crystal size of the rutile crystallinite increased to 100 nm. The apatite-forming ability of the films as deposited and after annealing was investigated in a kind of simulated body fluid with ion concentrations nearly equal to those of human blood plasma. The results indicate that ECR aided PLD is an effective way both to fabricate bioactive titanium dioxide thin films and to optimize the bioactivity of titanium dioxide, with both crystal size and defects of the film taken into account.
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This paper presents the fire performance results of light gauge steel frame (LSF) walls lined with single and double plasterboards, and externally insulated with rock fibre insulation as obtained using a finite element analysis based parametric study. A validated numerical model was used to study the influence of various fire curves developed for a range of compartment characteristics. Data from the parametric study was utilized to develop a simplified method to predict the fire resistance ratings of LSF walls exposed to realistic design fire curves. Further, this paper also presents the details of suitable fire design rules based on current cold-formed steel standards and the modifications proposed by previous researchers. Of these the recently developed design rules by Gunalan and Mahendran [1] were investigated to determine their applicability to predict the axial compression strengths and fire resistance ratings (FRR) of LSF walls exposed to realistic design fires. Finally, the stud failure times obtained from fire design rules and finite element studies were compared for LSF walls lined with single and double plasterboards, and externally insulated with rock fibres under realistic design fire curves.
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The ability to control the properties of single-wall nanotubes (SWNTs) produced in the arc discharge is important for many practical applications. Our experiments suggest that the length of SWNTs significantly increases (up to 4000 nm), along with the purity of the carbon deposit, when the magnetic field is applied to arc discharge. Scanning electron microscopy and transmission electron microscopy analyses have demonstrated that the carbon deposit produced in the magnetic-field-enhanced arc mainly consists of the isolated and bunched SWNTs. A model of a carbon nanotube interaction and growth in the thermal plasma was developed, which considers several important effects such as anode ablation that supplies the carbon plasma in an anodic arc discharge technique, and the momentum, charge, and energy transfer processes between nanotube and plasma. It is shown that the nanotube charge with respect to the plasma as well as nanotube length depend on plasma density and electric field in the interelectrode gap. For instance, nanotube charge changes from negative to positive value with an electron density decrease. The numerical simulations based on the Monte Carlo technique were performed, which explain an increase in the nanotubes produced in the magnetic-field-enhanced arc discharge. © 2008 American Institute of Physics.
Ways to increase the length of single wall carbon nanotubes in a magnetically enhanced arc discharge
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Ability to control the properties of single-wall nanotubes produced in the arc discharge is important for many practical applications. Our experiments suggest that the length and purity of single-wall nanotubes significantly increase when the magnetic field is applied to the arc discharge. A model of a single wall carbon nanotube interaction and growth in the thermal plasma was developed which considers several important effects such as anode ablation that supplies the carbon plasma in an anodic arc discharge technique, and the momentum, charge and energy transfer processes between nanotube and plasma. The numerical simulations based on Monte-Carlo technique were performed, which explain an increase of the nanotubes produced in the magnetic field - enhanced arc discharge.
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Electrostatic surface waves at the interface between a low-temperature nonisothermal dusty plasma and a metallic wall are investigated. The plasma contains massive negatively charged impurity or dust particles. It is shown that the impurities can significantly alter the characteristics and damping of the surface waves by reducing their phase velocity and causing charging-related damping.
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Using density functional theory, we have investigated the catalytic properties of bimetallic complex catalysts PtlAum(CO)n (l + m = 2, n = 1–3) in the reduction of SO2 by CO. Due to the strong coupling between the C-2p and metal 5d orbitals, pre-adsorption of CO molecules on the PtlAum is found to be very effective in not only reducing the activation energy, but also preventing poisoning by sulfur. As result of the coupling, the metal 5d band is broadened and down-shifted, and charge is transferred from the CO molecules to the PtlAum. As SO2 is adsorbed on the catalyst, partial charge moves to the anti-σ bonding orbitals between S and O in SO2, weakening the S–O bond strength. This effect is enhanced by pre-adsorbing up to three CO molecules, therefore the S–O bonds become vulnerable. Our results revealed the mechanism of the excellent catalytic properties of the bimetallic complex catalysts.
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Effect of near-wall transition regions on the surface wave propagation in a magnetoactive plasma layer bounded by a metal. It is shown that the account for inhomogeneities of plasma density or magnetic field causes an appearance of coupling between surface waves, propagating across magnetic field and localized near difference boundaries of the structure. The resonance damping of surface waves is analyzed too.
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Background In Australia, the profession of pharmacy has undergone many changes to adapt to the needs of the community. In recent years, concerns have been raised with evidence emerging of workforce saturation in traditional pharmacy practice sectors. It is not known how current final year pharmacy students’ perceive the different pharmacy career paths in this changing environment. Hence investigating students’ current experiences with their pharmacy course, interaction with the profession and developing an understanding of their career intentions would be an important step, as these students would make up a large proportion of future pharmacy workforce Objective The objective of this study was thus to investigate final year students’ career perspectives and the reasons for choosing pharmacy, satisfaction with this choice of pharmacy as a tertiary course and a possible future career, factors affecting satisfaction and intention of future career paths. Methods A quantitative cross sectional survey of final year students from 3 Australian universities followed by a qualitative semi-structured interview of a convenience sample of final year students from the University of Sydney. Results ‘Interest in health and medicine’ was the most important reason for choosing pharmacy (n=238). The majority of students were ‘somewhat satisfied’ with the choice of pharmacy (35.7%) as a course and possible future career. Positive associations were found between satisfaction and reasons for joining pharmacy such as ‘felt pharmacy is a good profession’ (p=0.003) while negative associations included ‘joined pharmacy as a gateway to medicine or dentistry’ (p=0.001). Quantitate and qualitative results showed the most frequent perception of community pharmacy was ‘changing’ while hospital and pharmaceutical industry was described as ‘competitive’ and ‘research’ respectively. The highest career intention was community followed by hospital pharmacy. Conclusion Complex factors including university experiences are involved in shaping students’ satisfaction and perception of career. This may relate to challenges in the community pharmacy sector, job opportunities in hospital and limited understanding of the pharmaceutical industry. The results offer insight for the profession in terms of entry into various roles and also to pharmacy educators for their roles in shaping curricula and placement experiences that attract future graduates to defined career pathways in pharmacy.
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Venous thromboembolism (VTE) is the term used to describe the disease process which presents as either deep vein thrombosis or pulmonary embolism. It is a major cause of death and disability worldwide and places a large financial burden on healthcare systems. Multiple risk factors have been identified for the development of VTE, including hospitalisation for acute medical illness and surgery. Documentation of VTE risk assessment is a critical part of any patient admission, driven by evidence that a risk assessment is a trigger for VTE prophylaxis to be considered. In the United Kingdom, healthcare services have set targets for VTE risk assessment documentation and financial incentives are linked to targets being met...
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This review assesses a survey of Jeff Wall's photographs at the MCA in Sydney. It analyses works such as "The Destroyed Room", "A Sudden Gust of Wind", and "A View from an Apartment". It also situates Wall as a preeminent early postmodern artist, post-photographer, and salon style maker of images.