1,720,994 research outputs found
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
Validity of bedside screening tests performed for aspiration detection in patients admitted to a public rehabilitation hospital
No full textIntrodução: a detecção precoce da disfagia e especificamente da aspiração é essencial para prevenir e reduzir as complicações de pacientes internados em hospitais de reabilitação. A avaliação inicial dos distúrbios da deglutição em pacientes internados é geralmente feita por testes de triagem à beira do leito (bedside screening tests) que tem baixa sensibilidade e especificidade. Identificar quais testes melhor discriminam pacientes com aspiração auxiliaria a programar a avalição racional destes pacientes. Objetivo: determinar a validade de testes de triagem realizados à beira do leito em detectar aspiração, com a videoendoscopia de deglutição (VED) como teste de referência. Métodos: um estudo prospectivo observacional foi realizado em 150 pacientes consecutivos admitidos no setor de reabilitação e readaptação de um hospital público terciário, submetidos à avaliação de preditores clínicos, ao questionário Eating Assessment Tool 10 (EAT-10), a um instrumento para avaliação da força e resistência da língua (Iowa Oral Performance Instrument [IOPI]), à medição do tempo de fonação máxima (TFM) e a um teste de deglutição (Volume-Viscosity Swallow Test [V-VST]). A validade dos testes de triagem em detectar aspiração, confirmada pela VED, foram calculadas. Resultados: dos 144 pacientes incluídos, 113 (78%) não tiveram aspiração e 31 (22%) tiveram aspiração. A força máxima da língua apresentou alta sensibilidade (92,3%) e baixa especificidade (18,6%) e acurácia (33,1%) para detectar aspiração. O V-VST mostrou sensibilidade, especificidade e acurácia para aspiração de 83,3%, 72,6% e 74,8%, respectivamente. A sensibilidade do EAT-10 e TMF para aspiração foi de 82,8% e 88% e especificidade foi de 57,7% e 32,4%, respectivamente. Conclusão: o resultado do presente estudo sugere que V-VST e o EAT-10 são bons métodos de triagem para detectar aspiração em pacientes admitidos em centro de reabilitação. O IOPI e TMF, apesar da excelente sensibilidade, apresentam baixa especificidade com baixo poder discriminatório entre paciente que não aspiram e aspiramIntroduction: early detection of dysphagia and specifically aspiration is essential to prevent and reduce complications of hospitalized patients in Rehabilitation Centers. Bedside screening tests are commonly used for the initial evaluation of swallowing in these settings, but they present insufficient and inconsistent sensitivity and specificity. To identify which tests better discriminate aspirating patients would allow defining a better diagnostic approach for these patients. Objective: to determine the validity of various bedside screening tests in detecting aspiration, with Flexible Endoscopic Evaluation of Swallowing (FEES) as the reference test. Methods: a prospective observational study was performed in 150 consecutive patients of a tertiary rehabilitation hospital, submitted to assessment of clinical predictors, the Eating Assessment Tool 10 (EAT-10) questionnaire, an instrument for assessing tongue strength and endurance (Iowa Oral Performance Instrument [IOPI]), Maximum phonation time (MPT) and a swallowing test (Volume- Viscosity Swallow Test [V-VST]). The validity of bedside screening tests in detecting aspiration, as confirmed by FEES, was calculated. Results: of the 144 patients included, 113 (78%) had no aspiration and 31 (22%) had aspiration. The maximum tongue strength presented high sensitivity (92.3%) and low specificity (18.6%) and accuracy (33.1%) to detect aspiration. The V-VST showed a sensitivity, specificity and accuracy for aspiration of 83.3%, 72.6% and 74.8%, respectively. The sensitivity of EAT-10 and TMF for aspiration was 82.8% and 88% and specificity was 57.7% and 32.4%, respectively. Conclusion: the results of the present study suggest that V-VST and EAT-10 are good screening methods for aspiration detection in patients admitted to a rehabilitation center. The IOPI and MPT, despite the excellent sensitivity, have low specificity with low discrimination power between patients who do and do not aspirat
Histological study on the effect of diode laser 980 nm and 1470 nm in vocal folds in a rabbit model
No full textINTRODUÇÃO: Os lasers têm sido utilizados em microcirurgia de laringe, permitindo corte e coagulação simultâneos que, em alguns casos, pode favorecer uma cirurgia exangue e mais precisa. Do ponto de vista vocal, o resultado cirúrgico ideal é aquele em que a lesão é removida com menor dano possível ao tecido adjacente, já que uma cicatrização inadequada da prega vocal pode resultar em disfonia de difícil reparação. O dano colateral dos lasers nos tecidos depende, entre outros fatores, do tipo de laser e de seu comprimento de onda. O laser diodo, quando comparado aos lasers mais utilizados em microcirurgias de laringe, tem como vantagens ser portátil, silencioso, transmite radiação através de uma fibra óptica fina e flexível o que facilita a manipulação do instrumento pelo cirurgião. Entretanto, as reações cicatriciais causadas pelo uso dos diferentes comprimentos de onda do laser diodo (980 nm e 1470 nm) nas pregas vocais ainda não foram estudadas. OBJETIVO: O objetivo desta pesquisa é estudar os efeitos histológicos da variação do comprimento de onda do laser de diodo de 980 nm e 1470 nm, no processo de cicatrização de pregas vocais de coelhos, em 7 e 30 dias após a lesão. MÉTODO: Vinte coelhos machos da raça New Zealand foram distribuídos aleatoriamente em quatro grupos, com cinco animais em cada grupo. Em cada prega vocal foi realizada uma única lesão por 7 segundos, através do contato da ponta da fibra do laser com a superfície do tecido. De um lado, o laser foi ajustado ao comprimento de onda de 980 nm e na prega vocal contralateral 1470nm. Nos grupos I e III, o modo de entrega de energia foi pulsado, enquanto que, nos grupos II e IV, foi contínuo. Após 30 dias (grupos I e II) e 7 dias (grupos III e IV) as laringes foram excisadas e submetidas a coloração com hematoxilina-eosina, além de coloração para colágeno e elastina. A análise histológica realizada foi quantitativa e subjetiva. RESULTADOS: Com o uso do laser diodo foi observado que o tecido apresentava sinais de manipulação (presença de reepitelização e presença de tecido de granulação com fibroblastos). Não foram observadas formações de úlceras, bolhas ou necrose. A extensão linear da lesão fibrótica apresentou diferença significativa, entre os dois comprimentos de onda, sendo maior no laser 980nm, que receberam feixes de laser no modo pulsado, em coelhos sacrificados 7 dias após a lesão. A densidade das fibras colágenas apresentou-se elevada ao uso do laser 1470 nm no mesmo grupo de animais. CONCLUSÃO: O uso de laser diodo demonstrou maior extensão da lesão fibrótica (laser 980 nm, modo pulsado) e maior densidade de colágeno (laser 1470 nm, modo pulsado), em animais na fase inicial (7 dias) da cicatrização. No entanto, ao analisarmos a evolução da cicatrização, tal padrão não fora observado ao longo dos 30 dias. Desta forma, a variação do comprimento de onda do laser diodo, não causou diferenças histológicas significativas na cicatrização inicialINTRODUCTION: Lasers have been used in endolaryngeal microsurgery, allowing simultaneous cutting and coagulation which, in some cases, may favor a bloodless and more accurate surgery. From a vocal point of view, the ideal surgical outcome is one in which the lesion is removed with the lowest possible damage to the adjacent tissue, since inadequate healing of the vocal fold may result in dysphonia that may be difficult to repair. The collateral damage of the lasers in the tissues depends, among other factors, on the type of laser and its wavelength. The diode laser, when compared to the lasers most used in laryngeal microsurgery, has the advantages of being portable, silent and to the fact it transmits radiation through a thin and flexible optical fiber, which facilitates the manipulation of the instrument by the surgeon. However, the cicatricial reactions caused by the use of different diode laser wavelengths (980 nm and 1470 nm) in the vocal folds have not been studied. OBJECTIVE: The aim of this study is to study the histological effects of diode laser wavelength variation of 980nm and 1470 nm in the healing process of vocal folds of rabbits, 7 and 30 days after the injury. METHOD: Twenty male New Zealand white rabbits were randomized into four groups, with five animals in each group. In each vocal fold, a single spot injury was performed during 7 seconds, through the contact of the tip of the laser fiber with the surface of the tissue. On one side, the laser was adjusted to the wavelength of 980 nm and on the contralateral vocal fold, 1470 nm. In groups I and III, the mode of energy delivery was pulsed, whereas in groups II and IV, it was continuous. After 30 days (groups I and II) and 7 days (groups III and IV) the larynx were excised and stained with hematoxylineosin, in addition to staining for collagen and elastin. The histological analysis was quantitative and subjective. RESULTS: With the use of diode laser, the tissue showed signs of manipulation (presence of reepithelialization and presence of granulation tissue with fibroblasts). No ulcer, blister or necrosis formations were observed. The linear extension of the fibrotic lesion showed a significant difference between the two wavelengths, being higher in the 980 nm laser, which received laser beams in the pulsed mode, in rabbits sacrificed 7 days after the lesion. The density of the collagen fibers was elevated to the use of the 1470 nm laser in the same group of animals. CONCLUSION: The use of diode laser showed a greater extension of the fibrotic lesion (980 nm laser, pulsed mode) and a higher density of collagen (laser 1470 nm, pulsed mode) in animals in the initial phase (7 days) of wound healing. However, when we analyzed the evolution of healing, such pattern had not been observed during the 30 days. Thus, the variation of wavelength of the diode laser did not cause significant histological differences in the initial healing of the vocal fold
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
Study of acute vocal fold healing after injury with different settings of 980nm diode laser in a rabbit model
No full textINTRODUÇÃO: A cicatriz em prega vocal que ocorre após injúria constitui causa importante de disfonia. A fonocirurgia ideal é aquela em que a lesão efetivamente removida com o menor dano possível ao tecido adjacente, a fim de reestabelecer a função da prega vocal ao mesmo tempo em que a sua ultraestrutura sua ultraestrutura é preservada. Tanto o bisturi frio quanto lasers em geral são aceitos como instrumentos para fonocirurgia. O laser de diodo tem sido usado no tratamento de doenças laríngeas. Entretanto, não há consenso quanto os parâmetros ideais desse aparelho para tal finalidade. Inexistem trabalhos que mostrem a forma ou a extensão da lesão provocada com laser de diodo em laringe e tampouco as reações histológicas e cicatriciais provocadas por ele. OBJETIVO: O objetivo desta pesquisa é estudar as alterações morfométricas e histopatológicas observadas nas pregas vocais de coelhos, sete dias após a lesão provocada com o laser de diodo, comparando diferentes configurações do dispositivo. MÉTODO: Vinte e um coelhos machos albinos da raça New Zealand foram distribuídos aleatoriamente em três grupos com sete animais por grupo. Foi realizada uma lesão única durante 20 segundos em cada prega vocal com a ponta da fibra em contato superficial com o tecido. Duas frequências de pulso foram comparadas no Grupo I (10Hz versus 1000Hz), diferentes potências no Grupo II (3W versus 5W) e modos de radiação distintos no Grupo III (pulsado versus contínuo). Após sete dias, as laringes foram excisadas e submetidas à coloração com hematoxilina-eosina, além de coloração histoquímica para colágeno e elastina. Foi realizada análise histológica quantitativa e subjetiva. RESULTADOS: o laser de diodo provocou: exocitose de células inflamatórias; edema de mucosa e submucosa; infiltrado celular extenso em torno da úlcera, composto por polimorfonucleares (especialmente eosinófilos), linfócitos e histiócitos; tecido de granulação com a presença de fibroblastos e vasos neoformados e áreas de necrose do tipo coagulativa. A extensão do processo inflamatório e a extensão linear da úlcera apresentaram diferença significativa entre as duas potências, e foi maior com uso do laser ajustado para 5W. A extensão do processo inflamatório, extensão linear da úlcera, profundidade da úlcera e profundidade do processo inflamatório apresentaram diferença significativa entre os dois modos de emissão do laser, isto é, maior no modo contínuo. A densidade das fibras colágenas apresentaram-se elevadas apenas ao uso do laser no modo contínuo, quando comparado ao modo pulsado. Não houve diferença estatística quanto à densidade de fibras elásticas. CONCLUSÃO: O uso do laser de diodo ajustado em potência de 5W ao invés 3W e o uso do modo contínuo ao invés do pulsado são capazes de aumentar significativamente a injúria térmica nas pregas vocais de coelhosINTRODUCTION. Scarring of the vocal folds is a relevant cause of dysphonia after injury. The ideal phonomicrosurgery would be the one that removes the vocal fold disease in order to restore the biomechanical function, while providing minimal disruption to the surrounding vocal fold layered structure. Steel scalpel and laser systems are widely accepted tools for vocal fold surgical procedures. The diode laser technique has been used in the treatment of laryngeal diseases. However, there is great variability among surgeons with regard to the use of the diode laser for laryngeal surgery and the ideal parameters for this procedure remain unclear. No description of the lesion extent or the vocal fold healing after injury with this device have been reported to date. OBJECTIVE: The aim of this research was to study the morphometric and histopathological changes seen in the vocal fold seven days after injury with the diode laser in a rabbit model, comparing different settings of the device. METHODS: Twenty-one male New Zealand white rabbits were randomized into three groups with seven animals per group. A single spot injury during 20 seconds was performed in each vocal fold with the fiber tip in superficially contact with the tissue. Two pulse frequency were compared in group I (10Hz versus 1000Hz), different powers in group II (3W versus 5W) and distinct wave mode of radiation in group III (pulsed versus continuous). After seven days, the larynges were harvested and subjected to H&E staining, histochemical staining for collagen and elastin, with quantitative and subjective histological analysis. RESULTS: the diode laser provoked exocytosis of inflammatory cells; edema of mucosa and submucosa; extensive cell infiltrate around the ulcer with polymorphonuclear cells (especially eosinophils), lymphocytes and histiocytes; granulation tissue with the presence of fibroblasts and neoformed vessels and areas of coagulative necrosis. The extent of the inflammatory infiltrate and the extent of the ablation crater showed to be greater with the 5W power use. The analyzes of extension of the extent of the inflammatory infiltrate, the extent of the ablation crater, the depth of the ablation crater and depth of the inflammatory process presented greater measurements with the continuous mode. The density of collagen fibers was higher when the laser was used in continuous wave mode. There was no statistically significant difference in elastic fiber density. CONCLUSION: Increasing power from 3W to 5W and using continuous wave rather than pulsed wave mode of the diode laser significantly increased the extent of thermal injury in the rabbit vocal fold
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
- …
