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Influence of air temperature on children water contacts with respect to schistosomiasis transmission risk in the Sourou Valley, Burkina Faso
Get PDFClimate and water contacts are among the most important risk factors of human schistosomiasis transmission. This study aimed to determine—through direct field observations—the influence of air temperature on the frequencies of children´s water contacts with respect to human schistosomiasis transmission risk in the Sourou Valley, located in the North-western part of Burkina Faso. The objectives of the study were: (i) to study the air temperature at which children have the sensation of heat and start looking for water as a means for natural cooling; and (ii) to study whether high frequencies of swimming or bathing may lead to a higher risks of schistosomiasis transmission. To do so, swimming or bathing were observed during two different periods: a cold one from 3rd January to 2nd February 2011 and a hot one from 3rd April to 3rd May 2011 in Toma-Île, a village totally surrounded by water. The results showed that daily mean air temperatures never exceeded 30 °C during the coldest period, while they were above this value during the hottest period. In total, swimming activities were observed 11/31 days during the coldest period and 31/31 during the hottest period. Bathing of children below the age of 5 years occurred on 55/62 days. 25 °C was the day mean air temperature from which children felt hot and began playing in water. The hourly occurrence of swimming and bathing showed peaks at 2 PM. This coincides with the diurnal maximum of infective cercariae present in the same water. Thus, in order to freshen up during hot periods of the day, children used to look for freshwater and thus expose themselves to a high schistosomiasis transmission risk
Geographic Determinants of Human Schistosomiasis Transmission in the Sourou Valley, Burkina Faso
Get PDFSchistosomiasis (also known as Bilharzia or Bilharziasis) is the second most prevalent neglected tropical disease (NTD) after hookworm and is caused by infection with blood flukes of the genus Schistosoma. More than 85% of the estimated 779 million people at risk worldwide are concentrated in Sub-Saharan Africa (SSA). Of the 207 million infested persons worldwide, more than 97% are concentrated in SSA. The geographic study of human schistosomiasis comes within the framework of geography of health with the target of putting into perspective the natural and social determinants of the states of health within an area of interest. The complexity and multiplicity of factors contributing to the endemicity of human schistosomiasis suggests that patterns are readily predicted at regional and national scales and that more complex models are required to predict patterns at local scales. This local fine scale approach was adopted in this research to assess schistosomiasis-susceptibility at the community level by integrating natural and social geographic determinants in Burkina Faso in general and the Sourou Valley in particular. Therefore, the present study, in its conception, aimed to collect useful background information for analysing human schistosomiasis ecology and diffusion as well as the access to health care services and associated infrastructures at the community level.
This study tried to provide answers to three specific questions: i) what are the natural and social geographic determinants of the disease and how do they interact in terms of infestation of local populations? ii) how do the determinants of the disease interact in terms of local environmental contamination? and iii) could natural and social geographic determinants be integrated to geographically map high schistosomiasis-susceptible communities in the Sourou Valley in Burkina Faso? These research questions have three underlying specific hypothesis: i) human infestation depends on diverse natural and social geographic determinants occurring through multiple factors and complex interactions; ii) local environmental contamination depends on diverse natural and social geographic determinants through a complex of interactions between multiple factors; and iii) the comprehensive, rapid and accurate mapping of high schistosomiasis-susceptible communities and sub-communities in the Sourou Valley is depends on the integration of diverse natural and social geographic determinants collected at the community level. Three specific objectives were defined to verify these hypotheses: i) to identify natural and social geographic elements at the local community level in order to understand their complex interactions with respect to human infestation; ii) to identify natural and social geographic elements at the local community level for understanding their complex interaction with respect to environmental contamination; and iii) to integrate identified natural and social geographic elements for geographic mapping of schistosomiasis-susceptible communities in the Sourou Valley.
The global and eco-systemic approach used in this work required us to dispose of a multitude of layers of information. In fact, the determination of communities favorable to schistosomiasis transmission requires the crossing of different spatialized data. Data gathering following the holistic perspective included geographic data (natural and social) as well as epidemiologic data. Some were readily available from archive sources, but most of them were ground collected data, particularly human and illness-related data. In this thesis, physical data were collected for assessing the heterogeneity and patterns of the vulnerability in time and space. Climatic variables were used to measure the temporal vulnerability of local populations while environmental layers were used to measure the spatial vulnerability of local populations. Human data such as population size and movement as well as access to infrastructures were collected to assess vulnerable communities within the AOI. Epidemiologic data was needed to assess and highlight the magnitude of the vulnerability to schistosomiasis at the community level. The spatial analysis followed a vertical approach. Sixteen geographic parameters were identified and integrated using GIS tool for mapping and understanding the varying pattern of schistosomiasis risk within the AOI.
Several natural and social geographic determinants explain the dysfunction between local populations and their environment which results in human infestation by schistosomes. The study demonstrated that the access to clean water, education, health and other related socio-economic infrastructures was strongly influenced by the settlement functions and its population size. The clean water supply did not succeed in discouraging people from the use of contaminated freshwater. Local populations travel greater distances to reach water bodies than they do for hydraulic works in the study area. Furthermore, results indicated that within the same community and for the same gender, women were more vulnerable to schistosomiasis due to their involvement in domestic activities that enhance their chances of coming in contact with water bodies. Within the same community and for the same age group, children vulnerability to schistosomiasis through recreational swimming was critically influenced by variability in air temperature. The role played by water bodies in the daily life of the respondents could be linked to poverty, socio-professional status, location of the settlements, culture, age and gender. These geographic determinants interact in a complex way resulting in vulnerability of local populations to schistosomiasis infestation.
Several natural and social geographic determinants influence defecation pattern of local populations which leads to environmental contamination. In the rural context, the defecation space utilization is mainly based on open air defecation. The demand for familial latrines in our AOI was strongly determined by land cover and proximity to the bush. In the peasant philosophy of defecation space utilization, defecation in the open air is a normal occurrence and feces encountered outdoors are mainly from children. Therefore, this defecation pattern contributes to environmental contamination. Children who are known to be heavily infected have less access to modern health care services. Traditional healers hold the monopoly for delivery of schistosomiasis treatment, hence, the expression “farafing fula (Blackman medicine) is preferred to tubabu fula (Whiteman medicine)”. The persistence of defecation in the open air is associated with poverty, socio-economic status, location of settlement, culture and age These geographic determinants interact in a complex that result in contamination of the local environment by its schistosomiasis-ill inhabitants
Through the application of geographic methods and techniques, we were able to assess schistosomiasis risk by crossing several layers of information putting into perspective the complex dynamic and functional relationships between natural and social geographic elements which promote the development of the disease in the Sourou valley. Risk maps were able to categorize settlements with a North-South similarity along the Sourou River from those with an East-West difference as one goes away from the Sourou River. Our model pointed to lakeside settlements as high schistosomiasis-susceptible settings. Furthermore, we demonstrated that the illness based mapping was cost effective: 4.4 times cheaper than the disease based mapping. Despite its limitations, this study was able to reveal communities with high-risk of schistosomiasis transmission. Therefore, it could be an indication that MDA is needed for control of schistosomiasis in the Sourou Valley
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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