967 resultados para Equivalent Effective Temperature


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A novel method has been developed to synthesize mesoporous silica spheres using commercial silica colloids (SNOWTEX) as precursors and electrolytes (ammonium nitrate and sodium chloride) as destabilizers. Crosslinked polyacrylamide hydrogel was used as a temporary barrier to obtain dispersible spherical mesoporous silica particles. The influences of synthesis conditions including solution composition and calcination temperature on the formation of the mesoporous silica particles were systematically investigated. The structure and morphology of the mesoporous silica particles were characterized via scanning electron microscopy (SEM) and N2 sorption technique. Mesoporous silica particles with particle diameters ranging from 0.5 to 1.6 μm were produced whilst the BET surface area was in the range of 31-123 m2 g-1. Their pore size could be adjusted from 14.1 to 28.8 nm by increasing the starting particle diameter from 20-30 nm up to 70-100 nm. A simple and cost effective method is reported that should open up new opportunities for the synthesis of scalable host materials with controllable structures.

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The dynamic nature of tissue temperature and the subcutaneous properties, such as blood flow, fatness, and metabolic rate, leads to variation in local skin temperature. Therefore, we investigated the effects of using multiple regions of interest when calculating weighted mean skin temperature from four local sites. Twenty-six healthy males completed a single trial in a thermonetural laboratory (mean ± SD): 24.0 (1.2) °C; 56 (8%) relative humidity; < 0.1 m/s air speed). Mean skin temperature was calculated from four local sites (neck, scapula, hand and shin) in accordance with International Standards using digital infrared thermography. A 50 x 50 mm square, defined by strips of aluminium tape, created six unique regions of interest, top left quadrant, top right quadrant, bottom left quadrant, bottom right quadrant, centre quadrant and the entire region of interest, at each of the local sites. The largest potential error in weighted mean skin temperature was calculated using a combination of a) the coolest and b) the warmest regions of interest at each of the local sites. Significant differences between the six regions interest were observed at the neck (P < 0.01), scapula (P < 0.001) and shin (P < 0.05); but not at the hand (P = 0.482). The largest difference (± SEM) at each site was as follows: neck 0.2 (0.1) °C; scapula 0.2 (0.0) °C; shin 0.1 (0.0) °C and hand 0.1 (0.1) °C. The largest potential error (mean ± SD) in weighted mean skin temperature was 0.4 (0.1) °C (P < 0.001) and the associated 95% limits of agreement for these differences was 0.2 to 0.5 °C. Although we observed differences in local and mean skin temperature based on the region of interest employed, these differences were minimal and are not considered physiologically meaningful.

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Purpose: Skin temperature assessment has historically been undertaken with conductive devices affixed to the skin. With the development of technology, infrared devices are increasingly utilised in the measurement of skin temperature. Therefore, our purpose was to evaluate the agreement between four skin temperature devices at rest, during exercise in the heat, and recovery. Methods: Mean skin temperature (T̅sk) was assessed in thirty healthy males during 30 min rest (24.0± 1.2°C, 56 ± 8%), 30 min cycle in the heat (38.0 ± 0.5°C, 41 ± 2%), and 45 min recovery(24.0 ± 1.3°C, 56 ± 9%). T̅sk was assessed at four sites using two conductive devices(thermistors, iButtons) and two infrared devices (infrared thermometer, infrared camera). Results: Bland–Altman plots demonstrated mean bias ± limits of agreement between the thermistors and iButtons as follows (rest, exercise, recovery): -0.01 ± 0.04, 0.26 ± 0.85, -0.37 ± 0.98°C; thermistors and infrared thermometer: 0.34 ± 0.44, -0.44 ± 1.23, -1.04 ± 1.75°C; thermistors and infrared camera (rest, recovery): 0.83 ± 0.77, 1.88 ± 1.87°C. Pairwise comparisons of T̅sk found significant differences (p < 0.05) between thermistors and both infrared devices during resting conditions, and significant differences between the thermistors and all other devices tested during exercise in the heat and recovery. Conclusions: These results indicate poor agreement between conductive and infrared devices at rest, during exercise in the heat, and subsequent recovery. Infrared devices may not be suitable for monitoring T̅sk in the presence of, or following, metabolic and environmental induced heat stress.

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Drying has been extensively used as a food preservation procedure. The longer life attained by drying is however accompanied by huge energy consumption and deterioration of quality. Moisture diffusivity is an important factor that is considered essential to understand for design, analysis, and optimization of drying processes for food and other materials. Without an accurate value of moisture diffusivity, drying kinetics, energy consumption, quality attributes such as shrinkage, texture, and microstructure cannot be predicted properly. However, moisture diffusivities differ due to variation of composition and microstructure of foodstuff and drying variables. For a particular food, it changes with many factors including moisture content, water holding capacity, process variables and physiochemical attributes of food. Published information on moisture diffusivities of banana is inadequate and sometimes inconsistent due to lack of precise repeatable analysis techniques. In this work, the effective moisture diffusivity of banana was determined by Thermogravimetric Analysis (TGA), which ensures precise measurements and reproduction of experiments. A TGA Q500 V20.13 Build 39 was deployed to obtain the drying curve of the food material. It was found that effective moisture diffusivity ranged from 6.63 x10-10 to 1.03 x10-9 and 1.34 x10-10 to 6.60 x10-10 for isothermal at 70 0C and non-isothermal process respectively.These values are consistent with the value of moisture diffusivity found in the literature.

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The definition of tourism “is the travel for recreational, leisure, family or business purposes, usually of a limited duration. Tourism is commonly associated with trans-national travel, but may also refer to travel to another location within the same country”. Tourism as an industry, in today’s modern language is a means of global communication between nations and travelers of all countries, introducing them to the various cultures and societies abroad, as well there history, ancient, historical sites, and languages. Hence, advertising overall has become a tool of necessity in this ever-growing global industry. Given that, tourism is a part of the infrastructure of any country’s economy the growth and development of tourism is of great importance. Advertising plays a vital and is a crucial tool in developing the countries tourism by attractively presenting the nations points-of-interests, historical and cultural. Advertising has a central role in expanding this industry, generating economic growth in this area, as well as creating direct and indirect employment, but most importantly a creative innovating competition in the national and international travel industry. Importantly, to achieve a successful tourist industry, the Travel Agencies and governmental offices of the Ministry’s of Tourism and Business must work hand-in-hand to attain these goals. This article shows the impact of the various media and advertising methods used in tourism, which assisted in identifying the correct tool for expanding the country’s industry of tourism. The results of this study illustrated that the appropriate tools for promotional strategies to attract domestic and foreign traveler’s, found to be the most effective were, handbook, internet advertising, TV, brochures, newspapers

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In recent times a widespread consensus on the reality and gravity of anthropogenic climate change has emerged. Perceived inadequacies in the Australian government’s legal and policy responses to climate change issues have resulted in environmental activists increasingly turning to the courts as a strategy to promote greater action to address adverse climate impacts. The efficacy of this strategy for achieving climate goals is limited by the time and expense of litigating, the restrictions inherent in environmental law administrative challenges, and the possibility that judicial decisions may be overruled by the legislature. To date, climate change litigation in Australia has met with varied success, yet its significance extends beyond the court room as an important mechanism for raising public, political and commercial awareness about climate change issues. Ultimately, however, the types of far-reaching changes needed to mitigate and manage adverse climate impacts require strong regulatory backing. The most effective approach to addressing the complex challenges posed by climate change is a coordinated suite of regulatory measures spearheaded by the Federal Government.

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The construction industry is a crucial component of the Hong Kong economy, and the safety and efficiency of workers are two of its main concerns. The current approach to training workers relies primarily on instilling practice and experience in conventional teacher-apprentice settings on and off site. Both have their limitations however, on-site training is very inefficient and interferes with progress on site, while off-site training provides little opportunity to develop the practical skills and awareness needed through hands-on experience. A more effective way is to train workers in safety awareness and efficient working by current novel information technologies. This paper describes a new and innovative prototype system – the Proactive Construction Management System (PCMS) – to train precast installation workers to be highly productive while being fully aware of the hazards involved. PCMS uses Chirp-Spread-Spectrum-based (CSS) real-time location technology and Unity3D-based data visualisation technology to track construction resources (people, equipment, materials, etc.) and provide real-time feedback and post-event visualisation analysis in a training environment. A trial of a precast facade installation on a real site demonstrates the benefits gained by PCMS in comparison with equivalent training using conventional methods. It is concluded that, although the study is based on specific industrial conditions found in Hong Kong construction projects, PCMS may well attract wider interest and use in future.

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It is argued that the smart cities model promise solutions to fuel sustainable development and a high quality of life with a wise management of natural resources, through participatory action and engagement. The paper provides a critical review of this model and application attempts of smart urban technologies in contemporary cities by particularly looking into emerging practices of ubiquitous eco-cities as exemplar smart cities initiatives. Through a thorough review of literature and best practices on the smart cities model, this paper attempts to address the research question of whether smart cities model is just another fashionable city brand or an effective urban development and management model to solve the problems of our cities. The findings shed light on urban planning and development considerations for the integration of smart urban technologies and their possible implications in shaping up of the built environment to produce prosperous and sustainable urban futures.

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This paper develops a dynamic model for cost-effective selection of sites for restoring biodiversity when habitat quality develops over time and is uncertain. A safety-first decision criterion is used for ensuring a minimum level of habitats, and this is formulated in a chance-constrained programming framework. The theoretical results show; (i) inclusion of quality growth reduces overall cost for achieving a future biodiversity target from relatively early establishment of habitats, but (ii) consideration of uncertainty in growth increases total cost and delays establishment, and (iii) cost-effective trading of habitat requires exchange rate between sites that varies over time. An empirical application to the red listed umbrella species - white-backed woodpecker - shows that the total cost of achieving habitat targets specified in the Swedish recovery plan is doubled if the target is to be achieved with high reliability, and that equilibrating price on a habitat trading market differs considerably between different quality growth combinations. © 2013 Elsevier GmbH.

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Introduced predators can have pronounced effects on naïve prey species; thus, predator control is often essential for conservation of threatened native species. Complete eradication of the predator, although desirable, may be elusive in budget-limited situations, whereas predator suppression is more feasible and may still achieve conservation goals. We used a stochastic predator-prey model based on a Lotka-Volterra system to investigate the cost-effectiveness of predator control to achieve prey conservation. We compared five control strategies: immediate eradication, removal of a constant number of predators (fixed-number control), removal of a constant proportion of predators (fixed-rate control), removal of predators that exceed a predetermined threshold (upper-trigger harvest), and removal of predators whenever their population falls below a lower predetermined threshold (lower-trigger harvest). We looked at the performance of these strategies when managers could always remove the full number of predators targeted by each strategy, subject to budget availability. Under this assumption immediate eradication reduced the threat to the prey population the most. We then examined the effect of reduced management success in meeting removal targets, assuming removal is more difficult at low predator densities. In this case there was a pronounced reduction in performance of the immediate eradication, fixed-number, and lower-trigger strategies. Although immediate eradication still yielded the highest expected minimum prey population size, upper-trigger harvest yielded the lowest probability of prey extinction and the greatest return on investment (as measured by improvement in expected minimum population size per amount spent). Upper-trigger harvest was relatively successful because it operated when predator density was highest, which is when predator removal targets can be more easily met and the effect of predators on the prey is most damaging. This suggests that controlling predators only when they are most abundant is the "best" strategy when financial resources are limited and eradication is unlikely. © 2008 Society for Conservation Biology.

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Background Explosive ordnance disposal (EOD) technicians are often required to wear specialised clothing combinations that not only protect against the risk of explosion but also potential chemical contamination. This heavy (>35kg) and encapsulating ensemble is likely to increase physiological strain by increasing metabolic heat production and impairing heat dissipation. This study investigated the physiological tolerance times of two different chemical protective undergarments, commonly worn with EOD personal protective clothing, in a range of simulated environmental extremes and work intensities Methods Seven males performed eighteen trials wearing two ensembles. The trials involved walking on a treadmill at 2.5, 4 and 5.5 km.h-1 at each of the following environmental conditions, 21, 30 and 37°C wet bulb globe temperature (WBGT). The trials were ceased if the participants’ core temperature reached 39°C, if heart rate exceeded 90% of maximum, if walking time reached 60 minutes or due to volitional fatigue. Results Physiological tolerance times ranged from 8 to 60 min and the duration (mean difference: 2.78 min, P>0.05) were similar in both ensembles. A significant effect for environment (21>30>37°C WBGT, P<0.05) and work intensity (2.5>4>5.5 km.h-1, P< 0.05) was observed in tolerance time. The majority of trials across both ensembles (101/126; 80.1%) were terminated due to participants achieving a heart rate equivalent to greater than 90% of their maximum. Conclusions Physiological tolerance times wearing these two chemical protective undergarments, worn underneath EOD personal protective clothing, were similar and predominantly limited by cardiovascular strain.

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This paper critically evaluates the empirical evidence of 36 studies regarding the comparative cost-effectiveness of group and individual cognitive behaviour therapy (CBT) as a whole, and also for specific mental disorders (e.g. depression, anxiety, substance abuse) or populations (e.g. children). Methods of calculating costs, as well as methods of comparing treatment outcomes were appraised and criticized. Overall, the evidence that group CBT is more cost-effective than individual CBT is mixed, with group CBT appearing to be more cost effective in treating depression and children, but less cost effective in treating drugs and alcohol dependence, anxiety and social phobias. In addition, methodological weaknesses in the studies assessed are noted. There is a need to improve cost calculation methodology, as well as more solid and a greater number of empirical cost-effectiveness studies before a firm conclusion can be reached that group CBT is more cost effective then individual CBT.

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Alcohol-related mortality and morbidity represents a substantial financial burden on communities across the world. Adolescence and young adulthood is a peak period for heavy episodic alcohol consumption, with over a third of all people aged 14-19 years having been at risk of acute alcoholrelated harm at least once in the previous 12 months (Australian Institute of Health and Welfare [AIHW], 2011). Excessive alcohol consumption has long been seen as a male problem; however, a gradual shift towards a social acceptance of female drunkenness has narrowed the gap in drinking quantity and style between men and women (Grucza, Bucholz, Rice, & Bierut, 2008). The presented data point to the vulnerability of women to the consequences of acute alcohol intoxication and indicate that alcohol-related offending by women is on the rise. Taken together, these findings reveal that alcohol-related harms and aggression for young women are becoming more prevalent and problematic. This report addressed these issues from a policing perspective...

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Issues addressed: Hand hygiene in hospitals is vital to limit the spread of infections. This study aimed to identify key beliefs underlying hospital nurses’ hand-hygiene decisions to consolidate strategies that encourage compliance. Methods: Informed by a theory of planned behaviour belief framework, nurses from 50 Australian hospitals (n = 797) responded to how likely behavioural beliefs (advantages and disadvantages), normative beliefs (important referents) and control beliefs (barriers) impacted on their hand-hygiene decisions following the introduction of a national ‘5 moments for hand hygiene’ initiative. Two weeks after completing the survey, they reported their hand-hygiene adherence. Stepwise regression analyses identified key beliefs that determined nurses’ hand-hygiene behaviour. Results: Reducing the chance of infection for co-workers influenced nurses’ hygiene behaviour, with lack of time and forgetfulness identified as barriers. Conclusions: Future efforts to improve hand hygiene should highlight the potential impact on colleagues and consider strategies to combat time constraints, as well as implementing workplace reminders to prompt greater hand-hygiene compliance. So what? Rather than emphasising the health of self and patients in efforts to encourage hand-hygiene practices, a focus on peer protection should be adopted and more effective workplace reminders should be implemented to combat forgetting.