1,720,955 research outputs found
Inaccurate early assessment of neurological severity in head injury
No full textIntubation, which requires sedation and myorelaxants, may lead to inaccurate neurological evaluation of severely head-injured patients. Aims of this study were to describe the early clinical evolution of traumatic brain injured (TBI) patients admitted to intensive care unit (ICU), to identify cases of over-estimated neurological severity, and to quantify the risk factors for this over-estimation. A total of 753 TBI patients consecutively admitted to ICU of three academic neurosurgical hospitals (NSH) were assessed. Cases whose severity was potentially over-estimated were identified by four criteria and indicated as "mistakenly severe" (MS): (1) no surgical intracranial masses; (2) could not follow commands at neurological assessment; (3) were dismissed from the ICU in < or =3 days to a regular ward; and (4) had regained the ability to obey commands. A total of 675 patients were intubated and/or sedated-paralyzed at the post-stabilization evaluation. In all, 304 patients had surgically treated intracranial masses. Among the 449 non-surgical cases, 58 patients fulfilling the criteria for MS were identified. The main features distinguishing MS from truly severe cases were younger age, higher Glasgow Coma Scale (GCS) score at all time points, Marshall classification of Computerized Tomographic (CT) scan mostly Diffuse Injury I and II, fewer pupillary abnormalities, and a lower frequency of hypoxia, hypotension, and extra-cranial injuries. In a certain proportion of non-surgical TBI patients, mostly intubated and sedated, neurological examination is difficult and severity can be over-estimated. Risk factors for this inaccurate evaluation can be identified, and clinical decisions should be based on further examination
Monitoring brain tissue oxygen tension in brain-injured patients reveals hypoxic episodes in normal-appearing and in peri-focal tissue
No full textOBJECTIVE : We compared brain tissue oxygen tension (PtiO2) measured in peri-focal and in normal-appearing brain parenchyma on computerized tomography (CT) in patients following traumatic brain injury (TBI). DESIGN: Prospective observational study. SETTING: Neurointensive care unit. PATIENTS AND PARTICIPANTS: Thirty-two consecutive TBI patients were subjected to PtiO2 monitoring. INTERVENTIONS: Peri-focal tissue was identified by the presence of a hypodense area of the contusion and/or within 1 cm from the core of the contusion. The position of the tip of the PtiO2 probe was assessed at follow-up CT scan. MEASUREMENTS AND RESULTS: Mean PtiO2 in the peri-contusional tissue was 19.7+/-2.1 mmHg and was lower than PtiO2 in normal-appearing tissue (25.5+/-1.5 mmHg, p < 0.05), despite a greater cerebral perfusion pressure (CPP) (73.7+/-2.3 mmHg vs. 67.4+/-1.4 mmHg, p < 0.05). We observed both in peri-focal tissue and in normal-appearing tissue episodes of brain hypoxia (PtiO2 < 20 mmHg for at least 10 min), whose median duration was longer in peri-focal tissue than in normal-appearing tissue (51% vs. 34% of monitoring time, p < 0.01). In peri-focal tissue, we observed a progressive PtiO2 increase from pathologic to normal values (p < 0.01). CONCLUSIONS: Multiple episodes of brain hypoxia occurred over the first 5 days following severe TBI. PtiO2 was lower in peri-contusional tissue than in normal-appearing tissue. In peri-contusional tissue, a progressive increase of PtiO2 from pathologic to normal values was observed over time, suggestive of an improvement at microcirculatory level
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
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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