1,720,962 research outputs found
Bone resorption and environmental exposure to cadmium in children: a cross - sectional study
Full text linkAbstract Background Exposure to cadmium has been associated with osteoporosis and fracture risk in women and elderly, but studies in children are lacking. In the present study we investigate the association between markers of bone demineralization [urinary calcium (Ca) and deoxypyridinoline (DPD) excretion] and urinary cadmium (Cd) excretion (as an index of lifetime body burden). Methods 155 schoolchildren from 2 elementary schools in Lahore, Pakistan were included. Urinary Cd was measured as an index of lifetime exposure. We assessed the multivariate-adjusted association of exposure with markers of bone resorption, urinary DPD as well as with Ca excretion. Results Urinary Cd averaged 0.50 nmol/mmol creatinine and was not influenced by age, height, weight and socio-economic status (SES). Independent of gender, age, height, weight and SES a doubling of urinary Cd was associated with a 1.72 times (p Conclusions Even in young children, low-level environmental exposure to cadmium is associated with evidence of bone resorption, suggesting a direct osteotoxic effect with increased calciuria. These findings might have clinical relevance at older age.</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
Gezondheidseffecten van milieuverontreiniging en kinderarbeid in Lahore, Pakistan
No full textThe increasing trend of immigration from villages and small cities to larger cities resulted in increased social and commercial activities in the metropolitan cities of developing countries, for example, Pakistan. The urbanization resulted in increased vehicular traffic which contributes to outdoor environmental air pollution, in addition to other pollutants including trace elements entering the environment from other sources. Particulate air pollution (PM) has various health effects. The impact can be either short term or long term. The effect on human health depends on the type of pollutant, concentration, duration of exposure, and personal susceptibility. A large body of published scientific evidence shows increased hospital visits, cardiopulmonary morbidity and mortality on days with higher PM. Physiological systems of children being in the growing stage, place them among the most vulnerable populations affected by PM. According to the guidelines of WHO the annual permitted value of PM below 2.5 and 10 µm aerodynamic diameter (PM2.5 and PM10) is 10 and 20 µg/m3, respectively. Unlike the developed world where the legislation has already been made and implemented to regulate PM, developing countries stand behind. In Pakistan, though the legislation is present in its preliminary form, the authorities are not able to implement it fully. As a result, the environmental pollution is high in mega-cities like Lahore, where PM10 has been reported >300 µg/m3. Child labour is prevailingextensively in Asia and the Pacific (with an estimated 127.3 million children at work). In Pakistan, the National Child Labor survey conducted in 1996 by the Federal Bureau of Statistics, reported 3.3 million of the40 million children (in the 5-14 years age group) to be economically active on a full-time basis. Epidemiologic studies and research on young workers suggest that children have higher health risks than adults when exposed to hazardous working environments. Moreover, several potential adverse health impacts of occupational exposures need to be studied in children. Few studies have investigated health consequences of child labour. The aim of the present research was a) to study the health effects of outdoor PM among apparently healthy schoolchildren, b) to estimate the urinary concentrations of metals in schoolchildren and working children, and c) to study the health effects of occupational exposures among children employed in selected industries, that is, brick kiln, carpetweaving and surgical instruments manufacturing.In chapter 2, we report the exposure to PM2.5 and PM10 among schoolchildren from a low and ahigh pollution area in Lahore, Pakistan. Exposure assessment was done by measuring PM with a portable laser operated mass analyzer. Blood pressure (BP) was measured with an automated instrument. We found that children living and attending school in an area of very high traffic-related air pollution had a substantially higher systolic (7.6 mmHg) and diastolic (4.5 mmHg) BP compared with children living in an area with lower PM. In chapter 3, we report the relation between exposure to low level environmental cadmium (Cd) exposure and urinary excretion of calcium (Ca)and deoxypyridinoline (DPD), a marker of bone resorption. Exposure assessment was carried out by estimation of urinary Cd by inductively-coupled plasma mass spectrometry (ICP-MS) and DPD by enzyme linked immunosorbent assay (ELISA). We found a consistent association between biomarkers of bone resorption and bone demineralization and Cd exposure in 10-year old children. For each doubling in urinary Cd excretion, bone resorption estimated by DPD increased by 1.72 nmol/mmol creatinine.In chapter 4, we report the work-related exposure to metals among children working in surgical instruments manufacturing units. Estimation of 20 metals was done in spot urine samples by ICP-MS. 8-Hydroxydeoxyguanosine (8-OHdG), a marker of DNA damage was measured by ELISA. Among child workers, this biomonitoring study revealed a substantial exposure to several metals, especially chromium (Cr) and nickel (Ni), which are established carcinogens. Concentrations of Ni were associated with evidence of increased oxidative DNA damage.In chapter 5, we report the respiratory health and metal exposure among schoolchildren and working children from brick kilnand carpet weaving industries. Exposure assessment was done by estimating metals in spot urine by ICP-MS. Respiratory health was assessed by performing spirometry and measuring fractional exhaled nitric oxide (FeNO). We found a high prevalence of respiratory symptoms in children exposedto urban air pollution and in working children, as well as evidence of a high exposure to several toxic metals. The concentrations of urinary As are in the order of those found in other Asian regions with high environmental exposure to As. The sources and pathways of exposure and the health significance of these findings need to be further investigated.Among the selected populations of schoolchildren and children working ineither brick kiln, carpet weaving or surgical industry, we estimated the environmental and occupational exposures. We found a) significantly increased systolic and diastolic blood pressure among schoolchildren from high pollution urban area, b) association of markers of bone resorption (DPD) and bone demineralization (Ca) and Cd exposure, c) high exposures to Cr and Ni among children working in surgical industry and the association of Ni with 8-OHdG, and d) high prevalence of respiratory symptoms in schoolchildren and working children as well as high levels of urinary As.Although our cross-sectional findings have limitations, they haveidentified and confirmed significant health threats among children in Pakistan. Hence, general and specific preventive and control measures should be implemented.status: Publishe
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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