Study of Graft Copolymerization of Acrylic Acid Onto Nata De Coco and Its Application as Microfiltration Membrane

Chemical and physical modifications of membrane can be carried out by radiation induced graft copolymerization. The aim of this research is to prepare graft copolymers of acrylic acid onto nata de coco (NDC-g-AAc) by radiation and to study the performance of grafted copolymer as microfiltration membrane. Using a total dose of 30 kGy, the highest degree of grafting obtained were 209% and 142% for r (weight ratio of monomers to nata de coco) equal to 61.3 and 35.7 respectively. The increasing degree of grafting resulted in decreasing flux due to high hydrogen bonding between grafted acrylic groups and water. It was found that the degree of swelling of NDC-g-AAc membrane with r = 35.7 was higher than that of r = 63.1. The changes of chemical structure of membrane were characterized by FTIR spectroscopy which showed a new band at 1720 cm-1 attributed to the carbonyl group of acrylic aci

Hong Kong secondary students' perspectives on selecting test difficultly level and learner washback: Effects of a graded approach to assessment

This sequential mixed-methods study investigates washback on learning in a high-stakes school exit examination by examining learner perceptions and reported behaviours in relation to learners’ beliefs and language learning experience, the role of other stakeholders in the washback mechanism, and socio-educational forces. The focus is the graded approach of the Hong Kong Diploma of Secondary Education English Language Examination (HKDSE-English), incorporated in 2012, that allows test-takers to choose between easier and more difficult sections for reading and listening-integrated skills papers. Inductive coding of focus groups involving 12 secondary students fed into the development of the Washback on Students’ Learning questionnaire, which was administered to another 150 learners. Exploratory factor analyses of identified washback effects revealed four major types straddling different settings (classrooms, tutorial schools, learners’ personal environment), and seven categories of mediating variables pertaining to learners themselves, other stakeholders, and societal influences. Simultaneous multiple regressions identified influential clusters of mediating variables and showed the strongest predictors for each macro-level washback type varied. At least one intrinsic and one extrinsic factor category significantly contributed to all types, reaffirming learner washback as a socially situated, negotiated construct. Implications related to the consequences, use, and fairness of the graded approach are discussed

Study of Graft Copolymerization of Acrylic Acid Onto Nata De Coco and its Application as Microfiltration Membrane

Chemical and physical modifications of membrane can be carried out by radiation induced graft copolymerization. The aim of this research is to prepare graft copolymers of acrylic acid onto nata de coco (NDC-g-AAc) by radiation and to study the performance of grafted copolymer as microfiltration membrane. Using a total dose of 30 kGy, the highest degree of grafting obtained were 209% and 142% for r (weight ratio of monomers to nata de coco) equal to 61.3 and 35.7 respectively. The increasing degree of grafting resulted in decreasing flux due to high hydrogen bonding between grafted acrylic groups and water. It was found that the degree of swelling of NDC-g-AAc membrane with r = 35.7 was higher than that of r = 63.1. The changes of chemical structure of membrane were characterized by FTIR spectroscopy which showed a new band at 1720 cm-1 attributed to the carbonyl group of acrylic aci

Clustering of cardiovascular disease risk‑factors in semi‑urban population in Northern Nigeria

Introduction: Non‑communicable diseases (NCDs) are major causes of morbidity and mortality particularly for developing countries. Large proportion of all NCDs deaths are occurring in low‑ and ‑middle‑income countries are estimated to occur in people under 70‑years‑old. These low‑ and middle‑income are undergoing epidemiological transition which allows the concomitant occurrence of both communicable and NCDs due to adoption of western life‑style that predisposes them to development of these diseases. It is also known that there are risk‑factors that tend to cluster in individuals and make them more susceptible to NCDs especially cardiovascular diseases (CVDs). Among NCDs, CVDs constitute the largest share responsible for 48% of all deaths due to NCDs. To determine extend of clustering of these risk‑factors in a semi‑urban community in northern Nigeria, a population‑based study was carried out.Materials and Methods: This study was conducted in Dakace, a semi‑urban settlement near Zaria. A simple random sampling of 199 eligible respondents out of 424 was adopted to select study participants. An interviewer‑administered questionnaire was used to collect socio‑demographic information, smoking habits, alcohol consumption as well as level of physical activity. The following measurements were carried out on these respondents: Blood pressure (BP), fasting blood glucose, serum lipids, weight, and height to calculate body mass index (BMI).Results: There were of 199 participants: 94 males (47.2%) and 105 females (52.8%) with an overall mean age of 39.9 ± 15.6 years. About 20% had no risk factor; more females than males had risk‑factors. Proportion of subjects with risk‑factors increase with increasing BMI, particularly high BP; physical activity does not protect subjects from developing risk‑factors.Conclusion: This study clearly shows that CVD risk‑factors are prevalent even in segment of the population that hitherto may be considered free and the prevalence of these risk‑factors are high compared to some obtained from other part of Nigeria.Keywords: Cardiovascular, clustering, Dakace, Northern Nigeria, risk‑factorsNigerian Journal of Clinical Practice • Oct-Dec 2013 • Vol 16 • Issue

Spotting the diffusion of New Psychoactive Substances over the Internet

Online availability and diffusion of New Psychoactive Substances (NPS) represent an emerging threat to healthcare systems. In this work, we analyse drugs forums, online shops, and Twitter. By mining the data from these sources, it is possible to understand the dynamics of drugs diffusion and their endorsement, as well as timely detecting new substances. We propose a set of visual analytics tools to support analysts in tackling NPS spreading and provide a better insight about drugs market and analysis

Classical diffusion of N interacting particles in one dimension: General results and asymptotic laws

I consider the coupled one-dimensional diffusion of a cluster of N classical particles with contact repulsion. General expressions are given for the probability distributions, allowing to obtain the transport coefficients. In the limit of large N, and within a gaussian approximation, the diffusion constant is found to behave as N^{-1} for the central particle and as (\ln N)^{-1} for the edge ones. Absolute correlations between the edge particles increase as (\ln N)^{2}. The asymptotic one-body distribution is obtained and discussed in relation of the statistics of extreme events.Comment: 6 pages, 2 eps figure

UK Breastfeeding Helpline support: An investigation of influences upon satisfaction

Background Incentive or reward schemes are becoming increasingly popular to motivate healthy lifestyle behaviours. In this paper, insights from a qualitative and descriptive study to investigate the uptake, impact and meanings of a breastfeeding incentive intervention integrated into an existing peer support programme (Star Buddies) are reported. The Star Buddies service employs breastfeeding peer supporters to support women across the ante-natal, intra-partum and post-partum period. Methods In a disadvantaged area of North West England, women initiating breastfeeding were recruited by peer supporters on the postnatal ward or soon after hospital discharge to participate in an 8 week incentive (gifts and vouchers) and breastfeeding peer supporter intervention. In-depth interviews were conducted with 26 women participants who engaged with the incentive intervention, and a focus group was held with the 4 community peer supporters who delivered the intervention. Descriptive analysis of routinely collected data for peer supporter contacts and breastfeeding outcomes before and after the incentive intervention triangulated and retrospectively provided the context for the qualitative thematic analysis. Results A global theme emerged of 'incentives as connectors', with two sub-themes of 'facilitating connections' and 'facilitating relationships and wellbeing'. The incentives were linked to discussion themes and gift giving facilitated peer supporter access for proactive weekly home visits to support women. Regular face to face contacts enabled meaningful relationships and new connections within and between the women, families, peer supporters and care providers to be formed and sustained. Participants in the incentive scheme received more home visits and total contact time with peer supporters compared to women before the incentive intervention. Full participation levels and breastfeeding rates at 6-8 weeks were similar for women before and after the incentive intervention. Conclusion The findings suggest that whilst the provision of incentives might not influence women's intentions or motivations to breastfeed, the connections forged provided psycho-social benefits for both programme users and peer supporters

Indigenous silk moth farming as a means to support Ranomafana National Park

We envisage a world where the rural poor can derive a livelihood from protecting forests instead of cutting them down; where development planners understand that habitat health is the keystone for human health and survival, and where conservation biologists understand that long - term solutions to biodiversity loss must be built around social programs which enable local people to thrive. Our vision, however, can only be achieved when scientists express the role of biodiversity conservation in economic terms (Baird and Dearden 2003), and development planners understand environmental complexity and its role in poverty alleviation. Our long - term goal is to develop a generalized approach to biodiversity conservation that will enable scientists and development professionals to identify, plan and initiate sustainable, small - scale businesses in ecologically important areas. This paper reports on a recent study to expand current production of wild silk and explore new types of silk as one economic means of biodiversity protection in Madagascar. Madagascar is one of the most important centers of world biodiversity and 90% of its species are forest dwelling. Nevertheless, 80% of the population are subsistence farmers (Kistler and Spack 2003), and the predominant agricultural practice is “tavy” or slash and burn. Less than 10 % of the original forest remains. Development and conservation communities can effectively prevent deforestation only when they counter the macroeconomic forces that drive people to clear land. Small-scale farmers cut down forests because national and international policies, market conditions or local institutions do not provide them with reasonable alternatives (Tomich et al. 2005). Furthermore, even when alternatives are made available, results are difficult to achieve in a short time. At least some actions need to be implemented pro-actively, in sites that are currently healthy but near areas of potential population growth. We have been working for the past year to develop an approach to identify high value export products (i.e. products whose value is likely to be least vulnerable to macroeconomic shock; Castellano and San 2005), that can be found in areas of high biodiversity and conservation importance. One such product may be wild silk. Wild silk can be sustainably harvested in remote areas and easily transported to commercial centers. To determine if wild silk is a potential means of income generation for people living in areas of Madagascar where silk has not been traditionally produced, we gathered three types of information: 1. The diversity of silk producing larvae in the Eastern Forest Corridor and specifically in Ranomafana 2. The physical properties of larval silk and their estimated commercial value 3. How to apply our data in order to select sites where wild silk production could have a maximum economic and conservation effect We emphasize that the work reported here is preliminary and that we are working to expand our database for silkworm larvae and potential projects sites. All of these data will be posted on the website for Conservation through Poverty Alleviation (www.cpali.org) as we progress. Elsewhere we report the life-history biology of the species found to date and analyze the economic resources that will need to be generated by local com-munities to engage in silk production for commercial markets (Craig and Weber, in prep.)