993 resultados para DIFFERENT MICROSTRUCTURES


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Exposure to ultrafine particles (diameter less than 100 nm) is an important topic in epidemiological and toxicological studies. This study used the average particle number size distribution data obtained from our measurement survey in major micro-environments, together with the people activity pattern data obtained from the Italian Human Activity Pattern Survey to estimate the tracheobronchial and alveolar dose of submicrometer particles for different population age groups in Italy. We developed a numerical methodology based on Monte Carlo method, in order to estimate the best combination from a probabilistic point of view. More than 106 different cases were analyzed according to a purpose built sub-routine and our results showed that the daily alveolar particle number and surface area deposited for all of the age groups considered was equal to 1.5 x 1011 particles and 2.5 x 1015 m2, respectively, varying slightly for males and females living in Northern or Southern Italy. In terms of tracheobronchial deposition, the corresponding values for daily particle number and surface area for all age groups was equal to 6.5 x 1010 particles and 9.9 x 1014 m2, respectively. Overall, the highest contributions were found to come from indoor cooking (female), working time (male) and transportation (i.e. traffic derived particles) (children).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The transmission of bacteria is more likely to occur from wet skin than from dry skin; therefore, the proper drying of hands after washing should be an integral part of the hand hygiene process in health care. This article systematically reviews the research on the hygienic efficacy of different hand-drying methods. A literature search was conducted in April 2011 using the electronic databases PubMed, Scopus, and Web of Science. Search terms used were hand dryer and hand drying. The search was limited to articles published in English from January 1970 through March 2011. Twelve studies were included in the review. Hand-drying effectiveness includes the speed of drying, degree of dryness, effective removal of bacteria, and prevention of cross-contamination. This review found little agreement regarding the relative effectiveness of electric air dryers. However, most studies suggest that paper towels can dry hands efficiently, remove bacteria effectively, and cause less contamination of the washroom environment. From a hygiene viewpoint, paper towels are superior to electric air dryers. Paper towels should be recommended in locations where hygiene is paramount, such as hospitals and clinics.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Potential adverse effects on children health may result from school exposure to airborne particles. To address this issue, measurements in terms of particle number concentration, particle size distribution and black carbon (BC) concentrations were performed in three school buildings in Cassino (Italy) and its suburbs, outside and inside of the classrooms during normal occupancy and use. Additional time resolved information was gathered on ventilation condition, classroom activity, and traffic count data around the schools were obtained using a video camera. Across the three investigated school buildings, the outdoor and indoor particle number concentration monitored down to 4 nm and up to 3 m ranged from 2.8×104 part cm-3 to 4.7×104 part cm-3 and from 2.0×104 part cm-3 to 3.5×104 part cm-3, respectively. The total particle concentrations were usually higher outdoors than indoors, because no indoor sources were detected. I/O measured was less than 1 (varying in a relatively narrow range from 0.63 to 0.74), however one school exhibited indoor concentrations higher than outdoor during the morning rush hours. Particle size distribution at the outdoor site showed high particle concentrations in different size ranges, varying during the day; in relation to the starting and finishing of school time two modes were found. BC concentrations were 5 times higher at the urban school compared with the suburban and suburban-to-urban differences were larger than the relative differences of ultrafine particle concentrations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The application of nanotechnology products has increased significantly in recent years. With their broad range of applications, including electronics, food and agriculture, power and energy, scientific instruments, clothing, cosmetics, buildings, biomedical and health, etc (Catanzariti, 2008), nanomaterials are an indispensible part of human life.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Dual-mode vibration of nanowires has been reported experimentally through actuation of the nanowire at its resonance frequency, which is expected to open up a variety of new modalities for the NEMS that could operate in the nonlinear regime. In the present work, we utilize large scale molecular dynamics simulations to investigate the dual-mode vibration of <110> Ag nanowires with triangular, rhombic and truncated rhombic cross-sections. By incorporating the generalized Young-Laplace equation into Euler-Bernoulli beam theory, the influence of surface effects on the dual-mode vibration is studied. Due to the different lattice spacing in principal axes of inertia of the {110} atomic layers, the NW is also modeled as a discrete system to reveal the influence from such specific atomic arrangement. It is found that the <110> Ag NW will under a dual-mode vibration if the actuation direction is deviated from the two principal axes of inertia. The predictions of the two first mode natural frequencies by the classical beam model appear underestimated comparing with the MD results, which are found to be enhanced by the discrete model. Particularly, the predictions by the beam theory with the contribution of surface effects are uniformly larger than the classical beam model, which exhibit better agreement with MD results for larger cross-sectional size. However, for ultrathin NWs, current consideration of surface effects is still experiencing certain inaccuracy. In all, for all different cross-sections, the inclusion of surface effects is found to reduce the difference between the two first mode natural frequencies. This trend is observed consistent with MD results. This study provides a first comprehensive investigation on the dual-mode vibration of <110> oriented Ag NWs, which is supposed to benefit the applications of NWs that acting as a resonating beam.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: There is a lack of theory relating to destination brand performance measurement in the destination branding literature, which emerged in the late 1990s (see for example Dosen, Vransevic, & Prebezac, 1998). Additionally, there is a lack of research about the importance of travel context in consumers’ destination decision making (Hu & Ritchie, 1993). This study develops a structural model to measure destination brand performance across different travel situations. The theory of planned behaviour (TpB) was utilised as a framework to underpin the consumer-based brand equity (CBBE) hierarchy to develop a model of destination brand performance. Research approach: A proposed model of destination brand performance was developed through a review of the literature. The first study was used to identify destination image attributes (the core construct) using an analysis of the literature, a document analysis, and personal interviews using the Repertory Test qualitative technique. Underpinned by Personal Construct Theory (PCT), the Repertory Test enables the elicitation of attributes consumers use to evaluate destinations when considering travel. Data was examined in the first study to i) identify any attribute differences in travel contexts and ii) create a scale for use in a questionnaire. A second study was conducted to test the proposed model using a questionnaire with eight groups of participants to assess four destinations across two travel contexts. The model was tested utilising structural equation modelling. Findings: The first study resulted in a list of 29 destination image attributes for use in a scale index. Attributes were assessed across travel contexts and few differences were identified. The second study assessed the congruence of destination brand identity (the destination marketing organisation’s desired image) and destination brand image (the actual perceptions held by consumers) using importance-performance analyses. Finally, the proposed model of destination brand performance was tested. Overall the data supported the model of destination brand performance across travel contexts and destinations. Additionally, this was compared to consumers’ decision sets, further supporting the model. Value: This research provides a contribution to the destination marketing literature through the development of a measurement of destination brand performance underpinned by TpB. Practically; it will provide destination marketing organisations with a tool to track destination brand performance, relative to key competing places, over time. This is important given the development of a destination brand is a long term endeavour.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Study Rationale The objective of the study was to explore if and how rural culture influences type II diabetes management and to better understand the social processes that rural people construct in coping with diabetes and its complications. In particular, the study aimed to analyse the interface and interactions between rural people with type II diabetes and the Australian health care system. Theoretical framework and methods The research applied constructivist grounded theory methods within an interpretive interactionist framework. Data from 39 semi-structured interviews with rural and urban people with type II diabetes plus a mix of rural health care providers were analysed to develop a theoretical understanding of the social processes that define diabetes management in that context. Results The analysis suggests that although type II diabetes imposes limitations that require adjustment and adaptation these processes are actively negotiated by rural people within the environmental context to fit the salient social understandings of autonomy and self-reliance. Thus people normalised self-reliant diabetes management behaviours because this was congruent with the rural culture. Factors that informed the actions of normalisation were the relationships between participants and health care professions, support and access to individual resources. Conclusions The findings point to ways in which rural self-reliance is conceived as the primary strategy of diabetic management. People face the paradox of engaging with a health care system that at the same time maximises individual responsibility for health and minimises the social support by which individuals manage the condition. The emphasis on self-reliance gives some legitimacy to a lack of prevention and chronic care services. Success of diabetic management behaviours is contingent on relative resources. Where there is good primary care there develop a number of downstream effects including a sense of empowerment to manage difficult rural environmental circumstances. This has particular bearing on health outcomes for people with fewer resources.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Virus-like particle-based vaccines for high-risk human papillomaviruses (HPVs) appear to have great promise; however, cell culture-derived vaccines will probably be very expensive. The optimization of expression of different codon-optimized versions of the HPV-16 L1 capsid protein gene in plants has been explored by means of transient expression from a novel suite of Agrobacterium tumefaciens binary expression vectors, which allow targeting of recombinant protein to the cytoplasm, endoplasmic reticulum (ER) or chloroplasts. A gene resynthesized to reflect human codon usage expresses better than the native gene, which expresses better than a plant-optimized gene. Moreover, chloroplast localization allows significantly higher levels of accumulation of L1 protein than does cytoplasmic localization, whilst ER retention was least successful. High levels of L1 (>17% total soluble protein) could be produced via transient expression: the protein assembled into higher-order structures visible by electron microscopy, and a concentrated extract was highly immunogenic in mice after subcutaneous injection and elicited high-titre neutralizing antibodies. Transgenic tobacco plants expressing a human codon-optimized gene linked to a chloroplast-targeting signal expressed L1 at levels up to 11% of the total soluble protein. These are the highest levels of HPV L1 expression reported for plants: these results, and the excellent immunogenicity of the product, significantly improve the prospects of making a conventional HPV vaccine by this means. © 2007 SGM.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objectives: To compare measures of fat-free mass (FFM) by three different bioelectrical impedance analysis (BIA) devices and to assess the agreement between three different equations validated in older adult and/or overweight populations. Design: Cross-sectional study. Setting: Orthopaedics ward of Brisbane public hospital, Australia. Participants: Twenty-two overweight, older Australians (72 yr ± 6.4, BMI 34 kg/m2 ± 5.5) with knee osteoarthritis. Measurements: Body composition was measured using three BIA devices: Tanita 300-GS (foot-to-foot), Impedimed DF50 (hand-to-foot) and Impedimed SFB7 (bioelectrical impedance spectroscopy (BIS)). Three equations for predicting FFM were selected based on their ability to be applied to an older adult and/ or overweight population. Impedance values were extracted from the hand-to-foot BIA device and included in the equations to estimate FFM. Results: The mean FFM measured by BIS (57.6 kg ± 9.1) differed significantly from those measured by foot-to-foot (54.6 kg ± 8.7) and hand-to-foot BIA (53.2 kg ± 10.5) (P < 0.001). The mean ± SD FFM predicted by three equations using raw data from hand-to-foot BIA were 54.7 kg ± 8.9, 54.7 kg ± 7.9 and 52.9 kg ± 11.05 respectively. These results did not differ from the FFM predicted by the hand-to-foot device (F = 2.66, P = 0.118). Conclusions: Our results suggest that foot-to-foot and hand-to-foot BIA may be used interchangeably in overweight older adults at the group level but due to the large limits of agreement may lead to unacceptable error in individuals. There was no difference between the three prediction equations however these results should be confirmed within a larger sample and against a reference standard.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Evaluation of the Get REAL programme in an inclusive primary school setting has indicated its effectiveness in promoting pro-social behaviour for children with high functioning Autism. However, two children with co-morbid diagnoses and complex personal circumstances showed less consistent improvements. In order to explain their unique trajectories, not readily derived from quantitative studies, an exploratory case study approach was used to examine contextual influences on patterns of progress. Multiple data sources included coded video footage from the Get REAL programme, school reports on conduct, and parents and classroom teacher reports using the Strengths and Difficulties Questionnaire. While results provide support for the efficacy of the Get REAL programme for the two children, they also highlight the value of co-ordinated strategies and collaborative individualised approaches in more complex cases. This paper outlines the Get REAL intervention and a range of other school and support agency strategies impacting progress.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Volunteering Qld’s Project Creatives continues to explore the critical role creative disciplines and creative people play in providing new models of engagement and action in social change and community work. This article explores three different non-profit organisations that have used collaborative photography to enable locals to empower themselves. Written by Alice Baroni a volunteer with the Education, Research and Policy Unit of Volunteering Qld. Alice is undertaking a PhD at the Queensland University of Technology, exploring (photo) journalism, participatory content creation and community photography in Brazil’s low income suburbs. She is part of the ARC Centre of Excellence for Creative Industries and Innovation, and a Brazilian research group ‘Storytellers and Narratives: Contemporary Journalism’. Two of the initiatives explored in this publication are Viva Favela and Imagens do Povo that are ideologically and physically supported by, respectively, Viva Rio and Observatório de Favelas, based in Rio de Janeiro, Brazil. ‘Favela’ is often translated simply as ‘slum’ or ‘shantytown’, but these terms connote negative characteristics such as shortage, poverty, and deprivation, which end up stigmatising these low-income suburbs. Fotografi Senza Frontiere (FSF) (Photographers Without Borders) is an Italian non-governmental organisation that gathers together a group of photographers who aim to provide youth from extreme regions in Nicaragua, Algeria, Argentina, Panama, Uganda, and Palestine with skills to photograph and document their own reality by establishing permanent photo laboratories. This idea, which is similar to that of Viva Favela and Imagens do Povo, is to enable youth to become professional photographers as a means of self-representation and self-empowerment. Afterwards, students become educators in established photographic labs so as to pass on what they have learnt through FSF’s photographic courses.