998 resultados para Sub-microscopic


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The present work shows the growth of nordstrandile microcrystals observed by transmission and scanning electron microscopy. Nordstrandite was synthesised from non-crystalline aluminium hydroxide reacted in 20% ethylene glycol/water solution, at room temperature. This material was characterized by TEM, SEM, SAED, XRD and EDS/TEM, during six month and revealed the formation and growth of nordstrandite. Fibrillar pseudoboehmite is the only aluminium hydroxide which could be identified during the first two weeks. The nuclei grow, from complete dissolution/recrystallization of pseudoboehmite fibrils, into platy rectangular microscrystals of nordstrandite. Some tabular microcrystals recrystallise, forming after six months only the mufti-point nordstrandite stars. This electron-optical study suggest that the star shape results from the overlapping of rectangular plates, and pseudoboehmite fibrils act as the precursor of nordstrandite crystallisation in ethylene glycol/water solution.

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The tunneling of composite systems, where breakup may occur during the barrier penetration process, is considered in connection with the fusion of halo-like radioactive, neutron- and proton-rich nuclei, on heavy targets. The large amount of recent and new data clearly indicates that breakup hinders the fusion at energies near and below the Coulomb barrier. However, clear evidence for enhancement due to halo properties seems to over ride the breakup hindrance at lower energies, owing, to a large extent, to the extended matter density distribution. In particular we report here that at sub-barrier energies the fusion cross section of the Borromean two-neutron halo nucleus (6)He with the actinide nucleus (238)U is significantly enhanced as compared to the fusion of a similar projectile with no halo. This conclusion differs from that of the original work, where it was claimed that no such enhancement ensues. This sub-barrier fusion enhancement is also observed in the (6)He + (209)Bi system. (C) 2010 Elsevier B.V. All rights reserved.

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Variation in wood properties for Picea abies trees and logs of different dimensions has been studied at two sites in southern Sweden of different site quality class. Trees have been classified as dominant or sub-dominant, according to their height. Log and board grades were classified and strength grade of boards, basic density and annual ring width measured. A similar study made on four northern sites was used as reference material.Sub-dominant trees were of superior quality in comparison to dominant trees, when classified by log and board grades or strength grading. Differences were accentuated for the second log where the sub-dominant trees had superior strength and low amount of boards with coarse branches. The results correspond well to those from the northern region, Jämtland. The classifica¬tion of boards as well as bending strength indicated superior properties on timber from northern sites even though the basic density was similar.

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Video exposure monitoring (VEM) is a group of methods used for occupational hygiene studies. The method is based on a combined use of video recordings with measurements taken with real-time monitoring instruments. A commonly used name for VEM is PIMEX. Since PIMEX initially was invented in the mid 1980’s have the method been implemented and developed in a number of countries. With the aim to give an updated picture of how VEM methods are used and to investigate needs for further development have a number of workshops been organised in Finland, UK, the Netherlands, Germany and Austria. Field studies have also been made with the aim to study to what extent the PIMEX method can improve workers motivation to actively take part in actions aimed at workplace improvements.The results from the workshops illustrates clearly that there is an impressive amount of experiences and ideas for the use of VEM within the network of the groups participating in the workshops. The sharing of these experiences between the groups, as well as dissemination of it to wider groups is, however, limited. The field studies made together with a number of welders indicate that their motivation to take part in workplace improvements is improved after the PIMEX intervention. The results are however not totally conclusive and further studies focusing on motivation are called for.It is recommended that strategies for VEM, for interventions in single workplaces, as well as for exposure categorisation and production of training material are further developed. It is also recommended to conduct a research project with the intention of evaluating the effects of the use of VEM as well as to disseminate knowledge about the potential of VEM to occupational hygiene experts and others who may benefit from its use.

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The thesis belongs to the field of lexical semantics studies, associated with describing the Russian linguistic world-image. The research focuses on the universal situation of purchase and sale as reflected in the Russian lexical standard and sub-standard. The work deals also with subjects related to the sphere of social linguistics: the social stratification of the language, the structure of sub-standard, etc. The thesis is a contribution to the description of the Russian linguistic world-image as well as to the further elaboration of the conceptional analysis method. The results are applicable in teaching Russian as a foreign language, particularly in lexis and Russian culture and mentality studies.

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BACKGROUND: Unsafe abortions are a serious public health problem and a major human rights issue. In low-income countries, where restrictive abortion laws are common, safe abortion care is not always available to women in need. Health care providers have an important role in the provision of abortion services. However, the shortage of health care providers in low-income countries is critical and exacerbated by the unwillingness of some health care providers to provide abortion services. The aim of this study was to identify, summarise and synthesise available research addressing health care providers' perceptions of and attitudes towards induced abortions in sub-Saharan Africa and Southeast Asia. METHODS: A systematic literature search of three databases was conducted in November 2014, as well as a manual search of reference lists. The selection criteria included quantitative and qualitative research studies written in English, regardless of the year of publication, exploring health care providers' perceptions of and attitudes towards induced abortions in sub-Saharan Africa and Southeast Asia. The quality of all articles that met the inclusion criteria was assessed. The studies were critically appraised, and thematic analysis was used to synthesise the data. RESULTS: Thirty-six studies, published during 1977 and 2014, including data from 15 different countries, met the inclusion criteria. Nine key themes were identified as influencing the health care providers' attitudes towards induced abortions: 1) human rights, 2) gender, 3) religion, 4) access, 5) unpreparedness, 6) quality of life, 7) ambivalence 8) quality of care and 9) stigma and victimisation. CONCLUSIONS: Health care providers in sub-Saharan Africa and Southeast Asia have moral-, social- and gender-based reservations about induced abortion. These reservations influence attitudes towards induced abortions and subsequently affect the relationship between the health care provider and the pregnant woman who wishes to have an abortion. A values clarification exercise among abortion care providers is needed.

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BACKGROUND: A large proportion of the annual 3.3 million neonatal deaths could be averted if there was a high uptake of basic evidence-based practices. In order to overcome this 'know-do' gap, there is an urgent need for in-depth understanding of knowledge translation (KT). A major factor to consider in the successful translation of knowledge into practice is the influence of organizational context. A theoretical framework highlighting this process is Promoting Action on Research Implementation in Health Services (PARIHS). However, research linked to this framework has almost exclusively been conducted in high-income countries. Therefore, the objective of this study was to examine the perceived relevance of the subelements of the organizational context cornerstone of the PARIHS framework, and also whether other factors in the organizational context were perceived to influence KT in a specific low-income setting. METHODS: This qualitative study was conducted in a district of Uganda, where focus group discussions and semi-structured interviews were conducted with midwives (n = 18) and managers (n = 5) within the catchment area of the general hospital. The interview guide was developed based on the context sub-elements in the PARIHS framework (receptive context, culture, leadership, and evaluation). Interviews were transcribed verbatim, followed by directed content analysis of the data. RESULTS: The sub-elements of organizational context in the PARIHS framework--i.e., receptive context, culture, leadership, and evaluation--also appear to be relevant in a low-income setting like Uganda, but there are additional factors to consider. Access to resources, commitment and informal payment, and community involvement were all perceived to play important roles for successful KT. CONCLUSIONS: In further development of the context assessment tool, assessing factors for successful implementation of evidence in low-income settings--resources, community involvement, and commitment and informal payment--should be considered for inclusion. For low-income settings, resources are of significant importance, and might be considered as a separate subelement of the PARIHS framework as a whole.

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Objective: (i) To describe sub-Saharan African (SSA) post-migration food habits and eating patterns; and (ii) to examine how the food habits of SSA households in Victoria reflect post-migration acculturation.
Design: A cross-sectional survey using a snowball sampling technique. Data on food habits and eating patterns were obtained using semi-structured, face-to-face interviews from November 2001 to April 2002.
Subjects: A total of 139 households of demographically diverse recent migrants from across sub-Saharan Africa.
Setting: Melbourne metropolitan and Melbourne fringes.
Analysis: Data were summarised using descriptive statistics.
Results: SSA migrants and refugees indicated dietary acculturation characterised by three processes: substitution, supplementation and modification of recipes. They experienced difficulty locating their traditional foods, in particular, African vegetables (34.2%), unprocessed maize meal (29.1%), camel milk (23.1%) and maize grain (13.7%). The new foods adopted since arrival were pizza, breakfast cereals and fast foods, but also included new fruits and vegetables. Takeaway food such as Pizza Hut or McDonalds featured prominently in the SSA post-migration diet. Reasons for eating out were favourite food (48.3%), routine family outing (38.3%), special occasion (33.3%) and no time to cook (25%). A significant change in meal pattern was the inclusion of breakfast, although 21% reported skipping breakfast.
Conclusion: Many of the observed dietary changes were not consistent with good health and may predispose this population to rapid weight gain and chronic disease. Rapid modernisation and the Anglo-Australian culture interact in a complex way with traditional eating and socialisation practices of SSA migrants. Understanding these forces can allow effective health promotion and community development strategies to be developed for the future health of SSA migrants and their communities.

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The study assessed the anthropometric status of 337 sub-Saharan African children aged between 3-12 years who migrated to Australia. These children were selected using a snowball sampling method stratified by age, gender and region of origin. The prevalence rates for overweight and obesity were 18.4% (95%CI: 14 - 23%) and 8.6% (95%CI: 6% -12%) respectively. The prevalence rates for the indicators of undernutrition were: wasting 4.3% (95%CI: 1.6%-9.1%), underweight 1.2% (95%CI: 0.3%-3.0%), and stunting 0.3 (95%CI: 0.0%-1.6%). Higher prevalence of overweight/obesity was associated with lower household income level, fewer siblings, lower birth weight, western African background, and single parent households (after controlling for demographic and socio-economic factors). Higher prevalence rates for underweight and wasting were associated with lower household income and shorter lengths of stay in Australia respectively. No effect was found for child's age, gender, parental education and occupation for both obesity and undernutrition indices. In conclusion, obesity and overweight are very prevalent in SSA migrant children and undernutrition, especially wasting, was also not uncommon in this target group.

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There has been an increase in Australia's intake of refugees and migrants from sub-Saharan Africa over the last two decades. These refugees have been exposed to nutritional risks prior to migration, which, together with changes associated with acculturation, impact on their health and nutritional status post-migration. However, there is a paucity of data in Australia that has examined the health and nutritional status of this ethnic minority in Australia. Despite basic research assessing the nutritional status of children, none have specifically concentrated on the health and nutritional situation of sub-Saharan refugee children. In the absence of such studies, this paper explores issues relating to obesity in sub-Saharan African refugee children within a cultural and public health framework. We begin by outlining the history of obesity and its cultural meaning. We then move to a consideration of predisposing factors for obesity and how these factors translate into obesity risk contexts of sub-Saharan refugees post-migration. We argue there are a number of key challenges related to culture and the relationship between socio-economic factors post-migration that require addressing by health professionals, dieticians and health educators to ensure the delivery of successful health outcomes.

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In this study, Australian brown coal fly ash particles have been collected from power station and analysed by scanning electron microscopy to obtain morphological information and elemental composition of individual particles. The most common particles found to be the irregular shape particle aggregates. Other shapes include ball shape with smooth surface and with some attachments; and crystal shape fine particles. The X-ray spectra of each fly ash particle revealed five groups of elemental composition, they are Si-rich particles; Ca-rich particles; Fe-rich particles; particles with Mg-Ca Matrix and particles with Si-Ca matrix. A particle sire distribution analysis has been conducted using particle size analyser and found to have a mean particle size of 21fim. The sample then was separated into fine and coarse fractions using aerodynamic classifier, and the elemental composition of both fractions were determined by ICP-AES. Borate fusion and acid dissolution method was used for sample preparation. It is found that some environmental sensitive elements such as Zn, Pb, Ni, K and Cu are enriched in fine fly ash particles. Ca has much higher contents in fine particles as well. Si and Mg have higher concentrations in coarse particles.

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This paper explores whether Chinese relationship building, Guanxi, is effective in crosscultural sub-national relationships. Derived from research into Sino-Australian Sister City Type Relationships and using material gathered through interviews in China and Australia, a modified Institutional Guanxi conceptual model has been developed. Some propositions are developed to link the components of the Guanxi conceptual model. Different methodologies are explored to determine the most effective way to test the hypotheses in a cross-cultural environment, and future research is outlined.