1,721,106 research outputs found
Hemorheology and microcirculation in some pathologies of internal medicine
No full textIt is very interesting in physiopathology to evaluate the blood flow in the microvasculature of patients affected by diabetes, arterial hypertension, lipoproteinosis, peripheral occlusive arterial disease (POAD) and liver failure.Aim. It is very interesting in physiopathology to evaluate the blood flow in the microvasculature of patients affected by diabetes, arterial hypertension, lipoproteinosis, peripheral occlusive arterial disease (POAD) and liver failure. Methods. We studied 4 groups. Group 1: controls formed by 25 healthy subjects (15 males and 10 females aged 36±3 years); group 2: diabetes, including 32 patients (group 2A, 20 subjects with diabetes type 1: 12 males and 8 females aged 43±4 years and group 2B, 12 subjects with diabetes type 2: 6 males and 6 females aged 45±3 years); group 3: liver failure, formed by 6 subjects (3 males and 3 females aged 44±5 years); group 4: hypertensives, 50 subjects (group 4A, 28 smokers 12 males and 16 females aged 40±4 years and group 4B, 22 non-smokers: 12 males and 10 females aged 38±3 years). We evaluated the capillary morphology using computerized videocapillaroscopy, the hemorheology (red blood cell - RBC deformability and aggregability) using LORCA (Laser assisted Optical Rotational Red Cell Analyzer) and tissue oxygenation using transcutaneous oxymeter (Periflux 5000 - Perimed). Statistical analysis were performed using the Student t-test. Results. The capillary loops in patients with diabetic microangiopathy had in 50% of the patients studied an image such as "deer horns", as "elephant nose" in 72% and as "cork screw" in 44%. In diabetics we found also a capillary rarefaction in 28% of them. An improvement in perfusion was observed in patients with liver failure one week after liver transplantation from cadaver in 83% of them. Morphological alterations were present in hypertensives (27% in non-smokers, 46% in smokers). The RBC deformability evaluated as elongation index (EI) and RBC aggregability (t1/2 expressed in seconds) were detected using LORCA. Group 1: EI 0.59±0.02, t1/2 3±1 s; group 2A: EI 0.55±0.01; t1/2 2±0.5 s p<0.05 vs controls; group 2B: EI 0.56±0.01; t1/2 2±0.2 s p<0.04 vs controls; group 3: EI 0.56±0.02, t1/2 2±0.4 s p<0.04; group 4A: EI 0.56±0.02, t1/2 2±0.6 s p<0.03; group 4B: 0.57±0.02, t1/2 2±0.6 s p<0.04. We evaluated also the TcpO2 at the dorsum of the right foot expressed in mmHg: group 1, 96±11 mmHg; group 2A, 74±9 p<0.05 vs controls; group 2B, 76±8 mmHg p<0.05; group 3, 69±6 mmHg p<0.05; group 4A, 70±5 mmHg p<0.05; group 4B, 77±9 mmHg p<0.05. Conclusion. This study indicates an interesting and complete methodology in order to evaluate the microcirculation condition in different pathologies inducing microvasculature alterations
New approach to the excitation of plate waves for piezoelectric thick-films devices
No full textA method is presented for exciting the propagation of plate waves in elastic guides. It is implemented in a device whose minimum working structure consists of a non-piezoelectric plane guide and two piezoelectric transducers operating as a generator and detector. The device is entirely in accordance with thick-film technology standard procedures. Both transducers are composed of a PZT ferroelectric layer deposited on a ceramic substrate and a suitable system of three coplanar metal electrodes placed inside the same layer. Beside setting the wavelength of propagation, the electrode system promotes piezoelectric deformations parallel to the substrate simultaneously contracting and extending contiguous active regions in the layer. Pure shear stresses are then induced on the involved guide surface, alternately distributed, with the spatial periodicity of the wave that will propagate in the guide. The propagation of several kinds of guided waves is possible so the selection of the one that meets a specific device design best is allowed. This work describes the design, realization and operation of a prototype structure consisting of an alumina plate guide and two pairs of piezoelectric thick-film transducers realized on it. The results related to the propagation of symmetric and asymmetric Lamb modes are reported. Moreover, the potential of the method is highlighted, emphasizing its effectiveness, easy implementation and application in the development of devices for the sensing and non-destructive testing areas
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
Unknown ankylosing spondylitis with only cardiac involvement in patient with surgical indication: Call for patient and family members immunological screening.
No full textHemorheological and microcirculation in healthy and diseased liver after liver transplantation: a review.
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