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Folic acid (FA) supplementation is recommended in the periconceptional period, for the prevention of neural tube defects. Limited data are available on the folate status of New Zealand (NZ) pregnant women and its association with FA supplementation intake. Objectives were to examine the relationship between plasma folate (PF) and reported FA supplement use at 15 weeks’ gestation and to explore socio-demographic and lifestyle factors associated with PF. We used data and blood samples from NZ participants of the Screening for Pregnancy Endpoints cohort study. Healthy nulliparous women with singleton pregnancy (n 1921) were interviewed and blood samples collected. PF was analysed via microbiological assay. Of the participants, 73 % reported taking an FA supplement at 15 weeks’ gestation – of these, 79 % were taking FA as part of/alongside a multivitamin supplement. Of FA supplement users, 56 % reported consuming a daily dose of ≥800 μg; 39 % reported taking less than 400 µg/d. Mean PF was significantly higher in women reporting FA supplementation (54·6 (se 1·5) nmol/l) v. no FA supplementation (35·1 (se 1·6) nmol/l) (P<0·0001). Reported daily FA supplement dose and PF were significantly positively correlated (r 0·41; P<0·05). Younger maternal age, Pacific and Maori ethnicity and obesity were negatively associated with PF levels; vegetarianism was positively associated with PF. Reported FA supplement dose was significantly associated with PF after adjustment for socio-demographic, lifestyle confounders and multivitamin intake. The relationship observed between FA supplementation and PF demonstrates that self-reported intake is a reliable proxy for FA supplement use in this study population.
Natural graphite can be exfoliated into thin films by trapping it at the interface between water and heptane [S. J Woltornist, A. J. Oyer, J-M. Y. Carrillo, A.V. Dobrynin, and D.H. Adamson, ACS Nano 7, 7062 (2013)]. In this work, we add functional elements into these graphitic thin films by introducing additives into the water phase prior to exfoliation. We report the successful incorporation of ZnO nanoparticles thereby enabling the composite films to act as effective ultraviolet photodetectors. In a similar manner, integration of silver nanowires is achieved, which results in an enhancement of the electrical conductivity of graphite.
Here we present our first results of a study of the neutral hydrogen gas (HI) in the southern spiral galaxy NGC 253 with the Australia Telescope Compact Array. The relative proximity of NGC 253 makes it a very suitable object for detailed studies of large-scale, as well as nuclear, gas dynamics. Several peculiar features have been found. The HI distribution is asymmetric in the outer regions, probably as a result of the strong warping of the spiral arms. A bar associated with the disc, clearly visible in the optical and near-infrared, also reveals its signature in the neutral hydrogen gas. HI absorption measurements reveal unusual motions of the gas in the nuclear region which seem to indicate a fast-rotating ring of cold gas as well as outflow of gas. Similar features have been found in other starburst galaxies, such as M 82, NGC 1808 and NGC 4945, and are interpreted in terms of bar-induced gas dynamics and star formation.
This study examined associations between loneliness, a construct associated with serious adverse mental health outcomes, and positive mental wellbeing. Validated measures of loneliness (represented by friendship-related loneliness, isolation, positive attitude to solitude, and negative attitude to solitude) and positive mental wellbeing were administered to 1,143 adolescents from urban and rural schools. Confirmatory factor analyses revealed satisfactory model fit for both measures. A structural equation model confirmed significant positive associations between positive mental wellbeing and friendship-related loneliness and positive attitude to solitude; a significant negative association was found for isolation. Regression analyses provided support for significant differences in these associations according to gender, age, and geographical location (although only marginally). The implications of these findings during adolescence are reviewed.
How much of global warming is due to human activities? How far will it be possible to adapt to changes of climate? Sir John Houghton's definitive, full colour guide to climate change answers these questions and more by providing the best and latest information available, including the latest IPCC findings. The simple, logical flow of ideas gives an invaluable grounding in the science, as well as the physical and human impacts of climate change, for undergraduate students across a wide range of disciplines. Accessible to both scientists and non-scientists, the text avoids mathematical equations and includes more technical material in boxes, while simple figures help students to understand the conclusions the science leads to without being overwhelmed by vast amounts of data. Questions for students to consider and test their understanding are included in each chapter, along with carefully selected further reading to expand their knowledge.
Global Warming is a topic that increasingly occupies the attention of the world. Is it really happening? If so, how much of it is due to human activities? How far will it be possible to adapt to changes of climate? What action to combat it can or should we take? How much will it cost? Or is it already too late for useful action? This book sets out to provide answers to all these questions by providing the best and latest information available.
I was privileged to chair or co-chair the Scientific Assessments for the Intergovernmental Panel on Climate Change (IPCC) from its inception in 1988 until 2002. During this period the IPCC published three major comprehensive reports – in 1990, 1995 and 2001 – that have influenced and informed those involved in climate change research and those concerned with the impacts of climate change. In 2007, a fourth assessment report was produced, and in 2014 the fifth assessment report was published. It is the extensive new material in this latest report that has provided the basis for the substantial revision necessary to update this fifth edition.
The IPCC reports have been widely recognised as the most authoritative and comprehensive assessments on a complex scientific subject ever produced by the world's scientific community. On the completion of the first assessment in 1990, I was asked to present it to Prime Minister Margaret Thatcher's cabinet – the first time an overhead projector had been used in the Cabinet Room in Number 10 Downing Street. In 2005, the work of the IPCC was cited in a joint statement urging action on climate change presented to the G8 meeting in that year by the Academies of Science of all G8 countries plus China, India and Brazil. The world's top scientists could not have provided stronger approval of the IPCC's work. An even wider endorsement came in 2007 when the IPCC was awarded a Nobel Peace Prize.