1,721,415 research outputs found
Maternal nutrition, maternal body composition during pregnancy and neonatal bone mass
No full textAims: to determine the maternal lifestyle and anthropometric factors before and during pregnancy that influence in utero and childhood bone accrual. In addition, to characterize the environmental predictors of changes in maternal bone mass, as measured by quantitative ultrasound of the calcaneus (QUS), during pregnancy. Methods: A cohort of healthy women was assessed before and during pregnancy and their offspring underwent anthropometric assessment, including whole body DXA, in the neonatal period. A second, older, birth cohort, now aged nine years, with records of their mother’s lifestyle and anthropometry during pregnancy, had anthropometric assessment including whole body and lumbar spine DXA. Results: Maternal fat stores, smoking in late pregnancy and parental height independently predicted neonatal whole body bone mass. Of these factors, maternal fat stores and height had persisting effects on childhood bone mass. In addition, there was a significant decline in maternal calcaneal QUS during pregnancy; greater loss was predicted by reduced triceps skin fold thickness, nulliparity, low milk intake in the pre-pregnancy period and being pregnant over the winter months. After adjustment for maternal size, greater SOS decline was associated with greater neonatal bone area and mineral content. Of the predictors of childhood anthropometry, birth weight and size predicted bone and lean mass at age nine years but not fat mass. Maternal height and cord blood calcium were independent determinants of bone mineral content at age nine years. Conclusion: We have demonstrated that maternal body build and lifestyle influence bone mineral accrual in the developing foetus and have persistent effects on post-natal growth, supporting the programming of skeletal growth by the maternal environment. The mechanism may involve maternal effects on foetal calcium homeostasis.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
Groundwater Hydrology
Full text linkThe two fields of knowledge “geology” and “hydrology” always go hand in hand, often giving rise to the terms “geohydrology” and “hydrogeology.” The importance of the science of water, commonly called “hydrologic science,” is always complemented by the “science of the interior of the earth.” Whereas hydrology is concerned with the quality and quantity of underground water, its movement, extraction, and recharge, geology talks of the rock matrix and the structure in which this water is contained, stored, and moved around.In recent times, the knowledge of geohydrology or the hydrology of groundwater has gained an impetus many times its original scale; and with that, acquisition, expansion, research, advancement, and dissemination of this knowledge have become more significant. With so many dimensions of geohydrology available for exploration, research, and technological advancement, any work contributing to any dimension of geohydrology and groundwater will find its right place. This compilation of chapters is going to play a very important part in furthering the knowledge of geohydrology and may prove an interesting and useful read for various cross-sections of academia, researchers, engineers, hydrologists, and all categories of water consumers
Groundwater
No full textWater inside the earth, the groundwater and the invisible resource is the most important source of survival of mankind on this globe. Part of the hydrological cycle between entry (percolation and recharge) and exit (natural or forced extraction and discharge), the groundwater fascinates all: engineers, hydrogeologists, agriculturists, environmentalists, scientists, academia, resource managers and domestic and industrial users. This book is the outcome of efforts of those eminent authors who despite their fascination were able to write upon some important facet of groundwater flow and the transport of pollutants with it. The dimensions covered range from simple descriptive narratives; to expose of analytical methods; to complex mathematical treatment; to numerical simulations and computer modeling. All areas have been touched upon for the sake of general readers, students, professional engineers and scientists
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