1,720,957 research outputs found
Computed tomographic and pathological study of equine cheek teeth infundibular caries
Get PDFSeveral studies have found equine maxillary cheek teeth infundibular disorders to affect most adult
horses. Even infundibulae that appear grossly normal on the occlusal surface may contain areas of
caries, defective cementum, or complete absence of cementum subocclusally. These defects can
range from possibly insignificant small developmental cemental defects deep in the infundibulum to
advanced coalescing infundibular caries leading to dental fracture.
The aim of this study was to characterize maxillary cheek teeth infundibular disorders by gross,
computed tomographic, and histopathological examinations of affected and control teeth. One
hundred maxillary cheek teeth that contained 200 infundibulae were extracted post-mortem from 30
horses, including 82 teeth with and 18 without occlusal surface infundibular caries. The occlusal
surface infundibular caries was graded using the modified Honma technique, which found 61.8% of
the 82 affected teeth to be affected by Grade 1 caries, 27.9% with grade 2 and 10.3% with grade 3
caries. The rostral infundibulae were more commonly affected by occlusal surface lesions (72%
affected) as compared to the caudal infundibulae (64% affected) and also had higher grades of
occlusal caries. The Triadan 09 position was greatly overrepresented in the diseased teeth,
comprising 50% (41/82) of teeth with visible occlusal caries. There was a significant association
between the grade of occlusal infundibular caries present and the Triadan positions of the teeth.
All teeth were then imaged by computed tomography (CT) to determine crown and infundibular
lengths, and to detect the presence and appearance of any subocclusal infundibular cemental
abnormalities. Extensive statistical analysis of dental crown and infundibular lengths were performed,
showing that relatively shorter infundibulae are more likely to be diseased. However, this finding can
be explained by the predominance of Triadan 09 and older teeth in the diseased group, both of which
have lower infundibular depth:crown length ratios. Computed tomography showed 182/200 (91%)
infundibulae to have infundibular lesions deep to the occlusal surface. No statistically significant
association was found between the presence of subocclusal infundibular defects and age of affected
horses, grade of caries, or the presence of visible occlusal infundibular lesions. Teeth affected by
occlusal caries were 1.3 times more likely to have subocclusal lesions than teeth without occlusal
caries. This study also proposes a relationship between the presence of developmental infundibular
cemental lesions and later caries formation.
Eight maxillary cheek teeth were then imaged using micro-computed tomography (microCT) which
provided much finer details of infundibular lesions. MicroCT images were also used to guide the sites
of sectioning of teeth for histopathological analysis, which found that the appearance of infundibular
cementum was much more variable than its appearance on standard CT or microCT. The cementum
of many infundibulae showed extensive sites of former vasculature that were not filled with
cementum. Other areas contained moth-eaten cement which often contained plant material and
cellular debris, independent of the appearance of the occlusal surface of the infundibulum. No
histological evidence of previous vasculature or of haemoglobin breakdown products were found in
infundibular cementum.
Major findings and interpretations of this study allow us to conclude:
- Many infundibulae are affected by occult subocclusal cemental lesions. These lesions appear
to have no association with the presence or absence of apparent occlusal surface infundibular
lesions, and also are not more significantly apparent in particular Triandan positions or in
horses of a particular age. As the subocclusal cemental lesions appear to be unrelated to the
presence of occlusal surface lesions, the relationship between infundibular cemental lesions
(both occlusal and subocclusal) and the development of clinical sequelae remains poorly
understood.
- Even in those infundibulae with no apparent occlusal surface infundibular caries, the
subocclusal region often contained hypoplastic cementum and, often, impacted feed material
at the most apical aspect of the infundibulum on histological examination. Therefore, there
must be a communication between the apical portion of the infundibulum and the occlusal
surface for this to occur, even in those that appear unaffected by a vascular channel defect or
infundibular caries.
- The strict definition of infundibular caries as opposed to normal cementum on the occlusal
surface of infundibulae is inadequate to describe the great variation in the appearance and
composition of infundibular cementum. Further classification of the subocclusal cemental
defects and expectations of normal subocclusal cementum may also be included for a more
complete understanding. There should be a standardisation of terminology used to describe
normal and defective infundibular regions both on the occlusal surface and subocclusally.
- It is likely that subocclusal cemental lesions, particularly areas of apical cemental hypoplasia,
become become impacted with feed material even before they are exposed on the occlusal
surface, which may allow severe (Grade 2 or 3) infundibular caries to form subocclusally long
before that portion of the tooth is exposed.
- Analysis of the Hounsfield Units (measurement of density of tissues on CT scan) and their
relationship to the histological appearance of the same tissues may allow us to determine if
an infundibulum contains normal or hypoplastic cementum, or impacted feed material without
more invasive investigatory methods
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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