1,721,350 research outputs found
Regression modelling of cervical cancer and Chlamydia incidence in the context of national screening programmes
No full textPrevention of cervical cancer development or reduction in undetected Chlamydia
incidence and further onward Chlamydia transmission can be achieved through
regular screening. Early detection through a regular screening programme is
essential to achieve this goal. A well established screening policy is needed to
improve screening efficiency.This PhD study demonstrated the use of mathematical and spatial modelling to
explore the risk factors through various regression models, to explore the relation
between socio-economic conditions and disease incidence, and also other
techniques including classification analysis, decision models, and simulation to
evaluate screening options. Based on the risk factors and risk grouping, different
groups may have different screening policies. Alternatively, geographical
differences can be taken into account by dividing areas into a few parts; the
population living in each part may be considered to have different risks of
developing cervical cancer or Chlamydia in their life time. Therefore, different
screening programmes and services could be provided to those populations
according their location or the risk groups which they belong to
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
Distribution, habitat association, and movement patterns of Sea Urchins (Diadematidae) in coral reefs, Peninsular Malaysia / Mok Man Ying
No full textSea urchins are keystone herbivores in coral reefs as they prevent coral-algae phase shift and promote coral resilience in the Caribbean. However, the knowledge of sea urchins in the Indo-Pacific region is not extensive and their role in marine ecosystems remains unidentified. To fill this knowledge gap, this study aimed to examine the population ecology of sea urchins in Peninsular Malaysia, and their relationship with the tropical coral reefs habitat, as the first step to explore their potential in promoting reef resilience. Firstly, geographical information on the density, diversity, and distribution of sea urchins in Peninsular Malaysia (The Sunda Shelf and Malacca Strait Marine Ecoregion) were collated using three approaches – literature, questionnaire and field surveys. From the field surveys, a total of seven species from five families with a mean density of 41.6 ± 52.98 individuals/100 m² were documented. When combined with the literature and questionnaire surveys, 10 species of sea urchins from six families can be found within Peninsular Malaysia. The first record of Prionocidaris bispinosa for Malaysia was documented at the intertidal seagrass meadow in Tanjung Kupang, Johor. The species composition of sea urchins between the ecoregions was similar but differed significantly between coral reefs and seagrass meadows. With the data gathered, species lists and maps illustrating the density, species richness and diversity hotspots of sea urchins were produced. Secondly, coral reef habitat association patterns for Diadema setosum and Echinothrix calamaris were determined in belt-transect surveys (n = 57), with transects laid parallel to shore at different depths at Pulau Rawa, Johor. Multivariate regression analysis identified D. setosum to be more associated with live coral cover and coral growth form; in contrast, the distribution of E. calamaris that was driven by habitat rugosity, water depth and live coral cover. These findings suggest contrasting species-habitat associations for the two co-existing species. Finally, the movement patterns of D. setosum— a key species on tropical coral reefs that is endemic in the Indo-Pacific region was documented. By tracking 25 tagged sea urchins over twenty-four hours in Pulau Rawa, the total travel distance (18.91 ± 11.56 m), movement speed (0.79 ± 0.5 m/hour), 24-h displacement (5.87 ± 6.32 m) and home range (8.24 ± 6.52 m) of D. setosum were documented, and to date are novel findings especially for nocturnal sea urchin movements. The absence of homing and aggregation behaviour that are commonly displayed by other sea urchin species as predator avoidance strategies, suggests that predation pressure on the studied reef is low. Given the limited information about sea urchins in Malaysia, this study appears to be the first in-depth study of its kind in the country, investigating their distribution and the importance of habitat in shaping their density distributions and movement patterns. The baseline data serve as valuable information in the planning and management of natural habitats for biodiversity and conservation in Malaysia’s marine ecosystem. Explicitly, this knowledge provides important insight for incorporating sea urchins in coral rehabilitation interventions to enhance the resilience of coral reefs on the brink of degradation
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
China, oil well machinery in Yanchang
No full textCaption from Report from Red China and Xi xing man ying: Makeshift machinery has to suffice at Yenchang [Yanchang].China: Yanan [Yanchang]. Oil wellForman, H. (1946). Report from Red China. London: Robert Hale Limited.; Forman, H. (1946). Xi xing man ying. Shanghai: Shanghai shu bao gong si.GrayscaleForman Nitrate Negatives, Box 1
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
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