1,720,965 research outputs found
Dying brain
No full textDying brain
Editor—Ancillary tests used to confirm clinically diagnosed
brain death may substantially influence the time of diagnosis,
as in the following case. A 48-yr-old woman was shot
to the head and was admitted to the hospital at 01:00
a.m. with a Glasgow Coma Scale (GCS) of 1 (eye), 5 (motor),
1 (verbal); brain tissue oxygen tension measured with an
intraparenchymal catheter was 12 mm Hg (normal range
15–35 mm Hg), and the intracranial pressure was 25 mm Hg.
At 07:00 a.m., GCS score was 3 with absent brainstem
reflexes. Brain CT revealed massive cerebral oedema, the
brain tissue oxygen tension was zero, and the intracranial
pressure was 81 mm Hg with a cerebral perfusion pressure
of zero. EEG showed a persistent low amplitude theta activity
at the vertex and transcranial Doppler (TCD) a persistent cerebral
blood flow in middle cerebral arteries (systolic flow velocity:
30 cm s–1) (Fig. 1A).
At 09:00 a.m. of the next day, EEG was flat, and the 6 h
observation period required by the Italian law to declare
brain death was started; however, a TCD still showed a very
low systolic flow velocity and a residual diastolic flow velocity
(Fig. 1B).
At 03:00 p.m., deep coma, absent reflex motor response
and brainstem reflexes, and flat EEG persisted. Brain death
was declared. TCD showed a reverberating flow indicating
cerebral circulatory arrest (Fig. 1C).
There is widespread acceptance of the concept of brain
death in the Western hemisphere,1 and a fairly uniform
agreement in Europe regarding the clinical criteria.2 There
is, however, considerable variation in the use of additional
confirmatory tests.1 2 These include flat EEG and determination
of cerebral circulatory arrest by means of cerebral
angiography, brain CT or MRI angiography, TCD, or cerebral
scintigraphy. In the UK,1 only clinical criteria are used and
brain death is defined as the complete, irreversible loss of
brainstem function. In Sweden,1 cerebral angiography is
the facultative ancillary test to confirm brain death; in
Italy, EEG is mandatory, while cerebral angiography, brain
CT angiography, TCD, or cerebral scintigraphy are all permitted
methods to document cerebral circulatory arrest in
children of ,1 yr of age, or if a complete and reliable clinical
evaluation is not possible
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
Aneurysmal Subarachnoid Hemorrhage in Pregnancy - Case Series, Review, and Pooled Data Analysis
No full textBackground: Aneurysmal subarachnoid haemorrhage (aSAH) during pregnancy represents an
important cause of maternal and foetal morbidity and mortality. Approaches to diagnostics and
treatment are still controversial and there are only a limited number of cases described in the literature.
Our study examines the management of aSAH in pregnant patients creating a case series by combining
patients from our hospital records with those from the limited available literature
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
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