1,720,998 research outputs found
The fetal and early life origins of adult disease
The fetal origins of adult disease (FOAD) hypothesis is based on the observation that men and women who were small at birth (low birthweight) have an increased risk of atherosclerotic cardiovascular disease (CVD) and the related diseases hypertension, type 2 diabetes and the Insulin Resistance Syndrome. Risk is increased further if they showed rapid weight gain in childhood or become obese. The hypothesis proposes that CVD is ‘programmed’ by under nutrition during critical periods of early development and that ‘poverty’ during early life creates a permanent vulnerability to ‘diseases of affluence’. This concept is arguably of greatest relevance to developing countries, where fetal growth restriction still affects large numbers of people, where economic progress is leading to the emergence of childhood and adult obesity, and where CVD and type 2 diabetes are rising rapidly. Its implication is that the prevention of adult disease should include strategies to improve maternal health and fetal growth. This paper reviews work leading to the FOAD hypothesis and the results of FOAD research in India. It also discusses some of the controversies surrounding the hypothesis, notably the debate as to whether the link between fetal growth restriction and adult CVD is mediated by environmental factors (such as maternal nutrition) or by genes
Maternal vitamin D deficiency and GDM risk: evidence for the case of investing more attention in antenatal clinics
Gestational diabetes mellitus (GDM) is a global public health problem, and in India, it affects about 20% of pregnancies. India, despite being a tropical country with abundant sunshine has a high prevalence (80%) of vitamin D deficiency (VDD) among reproductive-aged women. Global and Indian evidence links VDD with a higher risk of hyperglycaemia in pregnancy and GDM. VDD has also been implicated in gestational hypertension, preterm birth and poorer offspring health. Global scientific consensus acknowledges the need for maternal vitamin D screening and supplementation, but knowledge gaps exist about optimal blood levels (50-100 nmol/l), and the required vitamin D dosage (400-4000 IU). Diet can provide <10% of the vitamin D requirements, food fortification can deliver limited amounts, and hence optimal antenatal supplementation is key. Prenatal calcium supplements containing 400 IU of vitamin D may be sufficient for calcium absorption and bone health, but may not provide immunomodulatory benefits, including GDM prevention. Increasing evidence calls for higher maternal vitamin D requirements (2000-4000 IU) for skeletal, metabolic and immune health benefits. Current screening and supplementation for maternal VDD in India is low. We need to invest in future studies to determine optimal maternal vitamin D requirements and formulate policies for vitamin D supplementation to prevent GDM. Improving the maternal vitamin D status is an important nutritional priority for policymakers to reduce the large economic burden of non-communicable diseases (10% of India's gross domestic product), and eventually achieve the 2030 UN sustainable development goals.</p
Micronutrients and fetal growth
Fetal undernutrition affects large numbers of infants in developing countries, with adverse consequences for their immediate survival and lifelong health. It manifests as intrauterine growth retardation (IUGR), defined as birth weight <10th percentile, which probably underestimates the number failing to achieve full growth potential. Birth weight is a crude measure of the dynamic process of fetal growth and does not capture effects of fetal undernutrition on body composition and the development of specific tissues. The link between maternal nutrition and fetal nutrition is indirect. The fetus is nourished by a complex supply line that includes the mother's diet and absorption, endocrine status and metabolism, cardiovascular adaptations to pregnancy and placental function. Micronutrients are essential for growth, and maternal micronutrient deficiency, frequently multiple in developing countries, may be an important cause of IUGR. Supplementation of undernourished mothers with micronutrients has several benefits but there is little hard evidence of improved fetal growth. However, this has been inadequately tested. Most trials have only used single micronutrients and many were inconclusive because of methodological problems. Several food-based studies (some uncontrolled) suggest benefits from improving maternal dietary quality with micronutrient-dense foods. One trial of a multivitamin supplement (HIV-positive mothers, Tanzania) showed increased birth weight and fewer fetal deaths. Well-conducted randomized controlled trials of adequate sample size and including measures of effectiveness are needed in populations at high risk of micronutrient deficiency and IUGR and should include food-based interventions and better measurements of fetal growth, maternal metabolism, and long-term outcomes in the offspring
Higher maternal plasma folate but not vitamin B-12 concentrations during pregnancy are associated with better cognitive function scores in 9-10 year old children in south-india.
Folate and vitamin B-12 are essential for normal brain development. Few studies have examined the relationship of maternal folate and vitamin B-12 status during pregnancy and offspring cognitive function. To test the hypothesis that lower maternal plasma folate and vitamin B-12 concentrations and higher plasma homocysteine concentrations during pregnancy are associated with poorer neurodevelopment, 536 children (aged 9–10 y) from the Mysore Parthenon birth cohort underwent cognitive function assessment during 2007–2008 using 3 core tests from the Kaufman Assessment Battery, and additional tests measuring learning, long-term storage/retrieval, attention and concentration, and visuo-spatial and verbal abilities. Maternal folate, vitamin B-12, and homocysteine concentrations were measured at 30 ± 2 wk gestation. During pregnancy, 4% of mothers had low folate concentrations (<7 nmol/L), 42.5% had low vitamin B-12 concentrations (<150 pmol/L), and 3% had hyperhomocysteinemia (>10 µmol/L). The children's cognitive test scores increased by 0.1–0.2 SD per SD increase across the entire range of maternal folate concentrations (P < 0.001 for all), with no apparent associations at the deficiency level. The associations with learning, long-term storage/retrieval, visuo-spatial ability, attention, and concentration were independent of the parents' education, socioeconomic status, religion, and the child's sex, age, current size, and folate and vitamin B-12 concentrations. There were no consistent associations of maternal vitamin B-12 and homocysteine concentrations with childhood cognitive performance. In this Indian population, higher maternal folate, but not vitamin B-12, concentrations during pregnancy predicted better childhood cognitive ability. It also suggests that, in terms of neurodevelopment, the concentration used to define folate deficiency may be set too low
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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