997 resultados para 12923-005
Resumo:
In experiments at the high-power Z-facility at Sandia National Laboratory in Albuquerque, New Mexico, we have been able to produce a low density photoionized laboratory plasma of Fe mixed with NaF. The conditions in the experiment allow a meaningful comparison with X-ray emission from astrophysical sources. The charge state distributions of Fe, Na and F are determined in this plasma using high resolution X-ray spectroscopy. Independent measurements of the density and radiation flux indicate unprecedented values for the ionization parameter xi = 20-25 erg cm s(-1) under nearly steady-state conditions. First comparisons of the measured charge state distributions with X-ray photoionization models show reasonable agreement, although many questions remain.
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Using a before and after study design, we compared protocolised weaning from mechanical ventilation with usual non-protocolised practice in intensive care. Outcomes (duration of mechanical ventilation, duration of intubation, intensive care stay) and complications (re-intubations, tracheostomy, mortality) were compared between baseline (Phase I) and following implementation of protocolised weaning (Phase II). Over the same period, we collected data in a second (reference) unit to monitor practice changes over time. In the intervention unit, outcomes were longer in Phase II compared with Phase I (all p < 0.005). When adjusted for admission APACHE II score and diagnostic category, only intensive care stay remained significantly longer (p = 0.002). There were significantly more tracheostomies in Phase II (p = 0.004). The reference unit demonstrated no statistically significant differences in study outcomes or complications between Phases. Protocolised weaning did not reduce the duration of mechanical ventilation and was not associated with an increased rate of re-intubation or intensive care unit mortality.
Resumo:
Background: Hip protectors are protective pads designed to cover the greater trochanter and attenuate or disperse the force of a fall sufficiently to prevent a hip fracture. Promising results from randomised controlled trials in nursing homes have resulted in hip protectors being widely recommended in the health care literature and in national guidelines. Objectives: The objectives of the study were to identify characteristics of individual residents, and the organisational features of the homes in which they live, which may affect adherence to wearing hip protectors. Design: An observational, correlation study designed to identify factors related to adherence. Setting: Forty nursing and residential homes in the UK. Participants: 1346 residents of the homes who were not confined to bed and with no pressure sore on the hip. Methods: The introduction of an evidence-based policy to offer Safehips hip protectors to residents free of charge and with support from a nurse facilitator. Adherence to wearing the hip protectors was observed over 72 weeks. Results: Initial acceptance of the hip protectors was 37.2%. Continued adherence was 23.9% at 24 weeks; 23.2% at 48 weeks; and 19.9% at 72 weeks. Greater adherence was associated with the following individual resident characteristics: a greater degree of dependency (95% CI 1.39 - m3.78) and cognitive impairment (95% CI 1.01 - 2.98); being male rather than female (95% CI 1.06 - 2.48). Greater adherence was also associated with the following organisational characteristics of homes: fewer changes of senior manager during the study period (95% CI 1.01 - 8.51), and being resident in a home with a resident profile showing a greater proportion of residents with a higher degree of dependency (95% CI 1.04 - 1.27). There was wide a variation in the degree of success in implementation between homes (adherence of 0 - 100% at 24 weeks). Conclusions: Those implementing a policy of introducing hip protectors into nursing and residential homes should consider targeting residents with cognitive impairment. Such residents are at greater risk of hip fracture and appear to be more likely to continue wearing hip protectors. Those charged with implementing changes inpractice or policy should consider how the context for implementation can be optimised to increase the likelihood of success.
Resumo:
A dielectric barrier discharge (DBD) generated by flowing helium between the parallel-plate electrodes of an open air reactor has been characterized using time resolved optical and electrical measurements. A sinusoidal voltage of up to 5 kV (peak to peak) of frequencies from 3 to 50 kHz has been applied to the discharge electrodes. The helium flow rate is varied up to 10 litre min(-1). The adjustment of flow rate allows the creation of uniform DBDs with optimized input power equal to 120 +/- 10 mW cm(-3). At flow rates from 4 to 6 litre min(-1) a uniform DBD is obtained. The maxima in the line intensities of N-2(+) and helium at 391.4 nm and 706.5 nm, respectively, 2 under those conditions indicate the importance of helium metastables and He-2(+) in sustaining such a discharge. The power efficiency and discharge 2 current show maxima when the DBD In He/air is uniform. The gas temperature during the discharge has been measured as 360 +/- 20 K.
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The relationship between stockperson behaviour, measured as verbal and physical interactions with the dairy cows (no. ¼ 210), during milking and the subsequent milk yield obtained was examined. The numbers of steps and kicks made by the cows during milking was recorded. The behaviour of two stockteams, each consisting of two stockmen, were recorded over 10 weekend sessions. The two teams varied in the types of interactions and when the stockteam that performed more positive interactions worked with the cows (team A), the cows had a significantly higher milk yield (P , 0·05) although this difference was small (17·54 v. 17·44 kg). When team A was milking the cows also stepped and kicked on the platform significantly more ( P , 0·05) compared with team B. The results also indicated that while each stockteam tended to interact with the same cows each session, different stockpersons interacted with different cows. These findings highlight the importance of the role of the stockperson in milk output and dairy cow behaviour in a commercial setting.
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Scientific computation has unavoidable approximations built into its very fabric. One important source of error that is difficult to detect and control is round-off error propagation which originates from the use of finite precision arithmetic. We propose that there is a need to perform regular numerical `health checks' on scientific codes in order to detect the cancerous effect of round-off error propagation. This is particularly important in scientific codes that are built on legacy software. We advocate the use of the CADNA library as a suitable numerical screening tool. We present a case study to illustrate the practical use of CADNA in scientific codes that are of interest to the Computer Physics Communications readership. In doing so we hope to stimulate a greater awareness of round-off error propagation and present a practical means by which it can be analyzed and managed.
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This paper introduces a novel interface designed to help blind and visually impaired people to explore and navigate on the Web. In contrast to traditionally used assistive tools, such as screen readers and magnifiers, the new interface employs a combination of both audio and haptic features to provide spatial and navigational information to users. The haptic features are presented via a low-cost force feedback mouse allowing blind people to interact with the Web, in a similar fashion to their sighted counterparts. The audio provides navigational and textual information through the use of non-speech sounds and synthesised speech. Interacting with the multimodal interface offers a novel experience to target users, especially to those with total blindness. A series of experiments have been conducted to ascertain the usability of the interface and compare its performance to that of a traditional screen reader. Results have shown the advantages that the new multimodal interface offers blind and visually impaired people. This includes the enhanced perception of the spatial layout of Web pages, and navigation towards elements on a page. Certain issues regarding the design of the haptic and audio features raised in the evaluation are discussed and presented in terms of recommendations for future work.
Resumo:
Small changes of diet may reduce CVD risk. One example is the inclusion of nuts. They are rich in fibre, unsaturated fatty acids and phytonutrients. However, their fat content and energy density raise concerns that chronic consumption will promote weight gain. Randomised intervention studies are required to evaluate whether this concern is well founded. This study's aim was to determine if the inclusion of a 1440 kJ serving of almonds in the daily diet results in positive energy balance, and body composition change. During a 23-week cross-over design study, participants were required to consume almonds for 10 weeks and were provided no advice on how to include them in their diet. For another 10 weeks (order counter-balanced), participants followed their customary diet and there was a 3-week washout between. The study group consisted of twenty women. Potential mechanisms of energy dissipation were measured. Ten weeks of daily almond consumption did not cause a change in body weight. This was predominantly due to compensation for the energy contained in the almonds through reduced food intake from other sources. Moreover, inefficiency in the absorption of energy from almonds was documented (P <0·05). No changes in resting metabolic rate, thermic effect of food or total energy expenditure were noted. A daily 1440 kJ serving of almonds, sufficient to provide beneficial effects on cardiovascular risk factors, may be included in the diet with limited risk of weight gain. Whether this can be generalised to other high-fat energy dense foods warrants evaluation.
Resumo:
Transparency in nonprofit sector and foundations, as an element to enhance the confidence of stakeholders in the organization, is a fact shown by several studies in recent decades. Transparency can be considered in various fields and through different channels. In our study we focused on the analysis of the organizational and economic transparency of foundations, shown through the voluntary information on their Website. We review the theoretical previous studies published to put to the foundations within the framework of the social economy. This theoretical framework has focused on accountability that make foundations in relation to its social function and its management, especially since the most recent focus of information transparency across the Website.In this theoretical framework was made an index to quantify the voluntary information which is shown on its website. This index has been developed ad hoc for this study and applied to a group of large corporate foundations.With the application of these data are obtained two kind of results, to a descriptive level and to a inferential level.We analyzed the statistical correlation between economic transparency and organizational transparency offered in the Website through quantified variables by a multiple linear regression. This empirical analysis allows us to draw conclusions about the level of transparency offered by these organizations in relation to their organizational and financial information, as well as explain the relation between them.