applications to Saturn's rings

Seit ihrer Entdeckung im Jahre 1610 durch Galileo Galilei faszinieren die Ringe des Saturn sowohl Laien als auch Experten. Planetare Ringe finden sich in der Äquatorialebene aller vier Riesenplaneten unseres Sonnensystems und sind eines der eindruckvollsten Beispiele granularer Gase. Darunter gehören die Saturnringe zu den Bekanntesten. Sie bergen eine Vielzahl von Strukturen und erstrecken sich über mehr als 240 000 Kilometer, wobei sie weit weniger als 100 Meter dick sind. Unzählige kleinerer Körper bewegen sich auf leicht exzentrischen Kepler-ähnlichen Bahnen um den Zentralplaneten und bestehen dabei vorwiegend aus Eis. Die seit Juli 2004 im Orbit um den Saturn befindliche Raumsonde Cassini liefert atemberaubende Bilder und Daten, die nicht nur neue Erkenntnisse liefern, sondern auch alte Fragestellungen neu aufleben lassen. Dazu gehört z.B. die Frage nach dem Ursprung und den Entwicklungsstufen planetarer Ringe. Kürzlich, im äusseren A-Ring entdeckte Kleinmonde, deren Existenz schon viel früher postuliert wurde, weisen auf eventuell stattfindende Wachstumsprozesse hin. Da sich planetare Ringe jedoch hauptsächlich innerhalb der sogenannten Roche-Zone des jeweiligen Planeten befinden, ist ein effektives, allein auf gravitativen Wechselwirkungen beruhendes Größenwachstum nicht zu erwarten. Der Einfluß von Teilchenadhäsion auf diese Prozesse ist bis dato fraglich.thesi

Clinical Trial Data Management in Environmental Health Tailored for an African Setting

Clinical trial data management tools are widely available—some free to access and others relatively expensive, particularly for low- and middle-income countries. Such tools also do not always permit adaptation for local conditions nor include options to capture environmental and meteorological data. In the context of climate change and pressing environmental health threats, more studies that aim to assess the impacts of environmental change on public health are being carried out. Here, using freely available software, we tailor-made a clinical trial data management tool that managed all aspects of an intervention-based clinical trial to assess the impact of personal solar ultraviolet radiation exposure on vaccine e ectiveness. Data captured and associated procedures included patient data, scheduling, reporting, analysis and data management. Moreover, patient enrolment, recruitment, follow-up and decision-making in response to patient data were managed. Given the multidisciplinary study approach, the tool also managed all environmental and meteorological data for the rural African study site. Application of the tool ensured e cient communication between rural sites, a relatively high overall participant response rate (87%) and minimal loss to follow-up. This study suggests that it is possible to tailor-make a clinical trial data management tool for environmental and public health studies.The National Research Foundation (NRF) of South Africa and the South African Medical Research Council (SAMRC).www.mdpi.com/journal/ijerpham2020Geography, Geoinformatics and Meteorolog

Baseline assessment of child respiratory health in the Highveld Priority Area

Children are a highly susceptible population to the effects of air pollution. To establish a current baseline of child respiratory health and associated risk factors in the Highveld Priority Area, a quantitative questionnaire was carried out among parents or guardians of children aged between 9 and 11 years in Witbank and Middelburg. Key health outcomes of interest were asthma and upper and lower respiratory tract complications. Air quality data were obtained for Witbank and Middelburg and compared with recently gazetted National Standards to establish potential risks. The prevalence of health outcomes and associated risk factors, such as indoor fossil fuel burning and parental smoking were considered and key risk factors identified. A unique method for the analysis of poor quality responses was introduced in order to derive the most meaning from the data. The study findings showed the air quality to be of concern particularly in Witbank; however, it also showed a similarity between the air quality in both towns. The health outcome with the highest prevalence was hay fever (occurring in the previous 6 months) with 31.7%. The use of non-electric heating sources, parental smoking and mould in the house were risk factors of most concern for respiratory health. During bivariate analysis mould was found to be associated with a number of health outcomes, most notably having bronchitis, with a crude OR of 4.74. An adjusted odds ratio of 4.05 was found for smoking in the house and having bronchitis. An adjusted OR of 6.32 was found for using gas or paraffin and having episodes of wheezing. These results may be used to direct future research studies as well as assist air quality management practices in the area. Finally, a technique to handle contradictions in questionnaire responses was developed to maximise use of data collected for application in under-resourced research environments. Copyright 2011, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Albers, PN 2011, Baseline assessment of child respiratory health in the Highveld Priority Area, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd C12/4/230/gmDissertation (MSc)--University of Pretoria, 2011.School of Health Systems and Public Health (SHSPH)Unrestricte

School students’ knowledge and understanding of the Global Solar Ultraviolet Index

Background. The Global Solar Ultraviolet Index (UVI) is a health communication tool used to inform the public about the health risks of excess solar UV radiation and encourage appropriate sun-protection behaviour. Knowledge and understanding of the UVI has been evaluated among adult populations but not among school students.Objectives. To draw on previously unpublished data from two school-based studies, one in New Zealand (NZ) and the other in South Africa (SA), to investigate and compare students’ knowledge of the UVI and, where possible, report their understanding of UVI.Methods. Cross-sectional samples of schoolchildren in two countries answered questions on whether they had seen or heard of the UVI and questions aimed at probing their understanding of this measure.Results. Self-report questionnaires were completed by 1 177 students, comprising 472 NZ (264 year 8 (Y8), 214 year 4 (Y4) students) and 705 SA grade 7 primary-school students aged 8 - 13 years. More than half of the NZ Y8 students answered that they had previously heard about or seen the UVI, whereas significantly more SA students and NZ Y4 students replied that they had neither seen nor heard about the UVI. Among the NZ students who had seen or heard of the UVI, understanding of the tool was fairly good.Conclusion. The observed lack of awareness among many students in both countries provides an opportunity to introduce an innovative and age-appropriate UVI communication method that combines level of risk with behavioural responses to UVI categories and focus on personal relevance to the UVI message

School students’ knowledge and understanding of the Global Solar Ultraviolet Index

BACKGROUND. The Global Solar Ultraviolet Index (UVI) is a health communication tool used to inform the public about the health risks of excess solar UV radiation and encourage appropriate sun-protection behaviour. Knowledge and understanding of the UVI has been evaluated among adult populations but not among school students. OBJECTIVES. To draw on previously unpublished data from two school-based studies, one in New Zealand (NZ) and the other in South Africa (SA), to investigate and compare students’ knowledge of the UVI and, where possible, report their understanding of UVI. METHODS. Cross-sectional samples of schoolchildren in two countries answered questions on whether they had seen or heard of the UVI and questions aimed at probing their understanding of this measure. RESULTS. Self-report questionnaires were completed by 1 177 students, comprising 472 NZ (264 year 8 (Y8), 214 year 4 (Y4) students) and 705 SA grade 7 primary-school students aged 8 - 13 years. More than half of the NZ Y8 students answered that they had previously heard about or seen the UVI, whereas significantly more SA students and NZ Y4 students replied that they had neither seen nor heard about the UVI. Among the NZ students who had seen or heard of the UVI, understanding of the tool was fairly good. CONCLUSION. The observed lack of awareness among many students in both countries provides an opportunity to introduce an innovative and age-appropriate UVI communication method that combines level of risk with behavioural responses to UVI categories and focus on personal relevance to the UVI message.For the NZ project, Dr Wright received funding from the National Research Foundation of South Africa, the National Institute of Water and Atmospheric Research and an International PhD scholarship from the University of Otago. Dr Reeder and the Cancer Society Social and Behavioural Research Unit received funding from the Cancer Society of New Zealand Inc. and the University of Otago. Funding for the SA project was granted in part by the Cancer Association of South Africa, the Council for Scientific and Industrial Research and the Medical Research Council of South Africa.http://www.samj.org.zaam201

School students’ knowledge and understanding of the Global Solar Ultraviolet Index

BACKGROUND. The Global Solar Ultraviolet Index (UVI) is a health communication tool used to inform the public about the health risks of excess solar UV radiation and encourage appropriate sun-protection behaviour. Knowledge and understanding of the UVI has been evaluated among adult populations but not among school students. OBJECTIVES. To draw on previously unpublished data from two school-based studies, one in New Zealand (NZ) and the other in South Africa (SA), to investigate and compare students’ knowledge of the UVI and, where possible, report their understanding of UVI. METHODS. Cross-sectional samples of schoolchildren in two countries answered questions on whether they had seen or heard of the UVI and questions aimed at probing their understanding of this measure. RESULTS. Self-report questionnaires were completed by 1 177 students, comprising 472 NZ (264 year 8 (Y8), 214 year 4 (Y4) students) and 705 SA grade 7 primary-school students aged 8 - 13 years. More than half of the NZ Y8 students answered that they had previously heard about or seen the UVI, whereas significantly more SA students and NZ Y4 students replied that they had neither seen nor heard about the UVI. Among the NZ students who had seen or heard of the UVI, understanding of the tool was fairly good. CONCLUSION. The observed lack of awareness among many students in both countries provides an opportunity to introduce an innovative and age-appropriate UVI communication method that combines level of risk with behavioural responses to UVI categories and focus on personal relevance to the UVI message.For the NZ project, Dr Wright received funding from the National Research Foundation of South Africa, the National Institute of Water and Atmospheric Research and an International PhD scholarship from the University of Otago. Dr Reeder and the Cancer Society Social and Behavioural Research Unit received funding from the Cancer Society of New Zealand Inc. and the University of Otago. Funding for the SA project was granted in part by the Cancer Association of South Africa, the Council for Scientific and Industrial Research and the Medical Research Council of South Africa.http://www.samj.org.zaam201

Geographical differences in primary schoolchildren's key sun-related behaviours

South Africa receives high levels of solar ultraviolet radiation (UVR). Exposure to UVR has beneficial and harmful effects, the most common of which are vitamin D synthesis and skin cancer, respectively. Acute exposure during childhood is a known risk factor for melanoma. In South Africa where skin cancers account for a third of all histopathologically diagnosed cancers, information on behaviour patterns and protection use is needed to inform awareness campaigns. Hence, this article aimed to perform an exploratory, feasibility study on the sun-related behaviours of urban primary schoolchildren by province. In general, use of sun protection was inconsistent and 52% of children reported sunburn. Generally, children from schools in the eastern part of the country self-reported higher incidence of suntan and sunburn compared to the western half. Similarly, children in Limpopo, Eastern Cape, Mpumalanga and North-West tended to use sun protection more often compared to the remaining provinces, although hat/cap usage and clothing were comparably high in the Northern Cape and KwaZulu-Natal, respectively. Children in the Western Cape had a high incidence of sunburn and amongst the lowest use of sun protection; this province is also known to have skin cancer incidence rates as high as those in Australia. While results are not representative of all of South Africa, they provide some indication that there is much to be done to raise levels of sunrelated knowledge and tailor safe sun behaviours.http://www.tandfonline.com/loi/rsag202017-08-31hb2016Geography, Geoinformatics and Meteorolog

Household fuel use and child respiratory ill health in two towns in Mpumalanga, South Africa

BACKGROUND : This cross-sectional study examined respiratory health outcomes and associated risk factors in children living in a part of South Africa characterised by high levels of air pollution. METHODS : A questionnaire was used to collect self-reported respiratory health and risk factor data from the parents/guardians of children between the ages of 9 and 11 years attending primary schools in the study area. Six government schools were selected based on their location, class size and willingness to participate. Univariate and bivariate analyses as well as logistic regression analysis were performed on the data, using a p-value of 0.25 and biological plausibility. RESULTS : The overall prevalence of respiratory ill-health symptoms was 34.1%. The prevalence of respiratory ill-health conditions was significantly elevated among children from households using non-electrical fuels v. electricity for cooking (43.9% v. 31.6%; adjusted p-value 0.005). The same was noted among those using non-electrical fuels for heating (37.8% v. 29.0%). CONCLUSION : The elevated prevalence of some respiratory health outcomes among schoolchildren, especially in conjunction with domestic fossil fuel burning, is of concern. The data collected in this study may be used to complement or form a basis for future policy regarding indoor or ambient air quality in the area.Council for Scientific and Industrial Researchhttp://www.samj.org.zahb201