1,721,068 research outputs found
Self-oscillation free 0.35 μm Si/SiGe BiCMOS X-band digital frequency divider
No full textThis letter reports a digital master-slave D-type register divide-by-512 frequency divider designed in a 0.35 μm Si/SiGe BiCMOS technology. The 600 x 1200 μm2 circuit operates up to 9.5 GHz dissipating 120 mW. Self-oscillations are avoided by the use of a radio frequency carrier detector that controls the bias of the last six registers. © 2008 IEEE
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
Eosinophil cationic protein in infants with respiratory syncytial virus bronchiolitis: Predictive value for subsequent development of persistent wheezing
No full textInfants with acute bronchiolitis during the first months of life are at increased risk of developing persistent wheezing and bronchial asthma later in life. The study of eosinophil cationic protein (ECP) suggests that eosinophil-related inflammatory mechanisms may play a role in respiratory syncytial virus (RSV) bronchiolitis. The aim of our study was to verify whether serum ECP (s-ECP) measurements are useful in predicting the development of persistent wheezing in children affected by RSV bronchiolitis during a 5 years follow-up period. Forty-eight infants were enrolled prospectively (mean age: 153.5 days). All had a clinical and radiological diagnosis of acute bronchiolitis and confirmed RSV infection. Peripheral eosinophil counts, levels of s-ECP, and serum IgE concentrations were measured during bronchiolitis. Five years later the children were re-evaluated in regard to their respiratory symptoms (standardized questionnaires) and atopic status (specific IgE levels). We observed significantly higher s-ECP levels (P < 0.001) at enrollment in subjects who developed persistent wheezing compared to subjects who did not show late wheezing. Initial s-ECP values allowed significant and correct prediction of persistent wheezing (P < 0.001). The risk to develop respiratory symptoms was 9.73 higher for infants with s-ECP levels greater than or equal to 8 mug/L than for those with s-ECP levels <8 mug/L (P < 0.000). In conclusion, our study suggests that s-ECP levels in infants with bronchiolitis are useful in predicting the risk to develop wheezing in the subsequent 5 years. (C) 2001 Wiley-Liss, Inc
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
Low-density areas on high-resolution computed tomograms in chronic pediatric asthma
No full textObjective: In children with chronic persistent asthma, we evaluated whether the presence of increased residual volume (RV) after anti-inflammatory treatment correlates with the detection of low-density areas on high-resolution computed tomography (HRCT), similar to those in emphysema. Methods: Children with a confirmed diagnosis of asthma (n = 32) were enrolled in a prospective study. All patients had reduction of airflow in the peripheral airways, increased RV and increased serum eosinophil cationic protein (ECP) values indicating airway inflammation. All the children were treated with salmeterol (50 mug twice daily) and fluticasone (250 mug twice daily) for a 3-month period. Results: At the end of treatment, peripheral eosinophil counts, serum ECP, forced expiratory volume in 1 second (FEV1), mean forced expiratory flow during the middle half of forced vital capacity (FEF25-76), RV, and total lung capacity values improved in all the patients. HRCT was normal in 22 children (68.8%); in the remaining 10 subjects, low-density areas were found despite normalization of FEV1, FEF25-75, and significant reduction in ECP. A significant correlation was found between persistence of RV values > 150% predicted and the presence of low-density areas on HRCT (r = 0.84, P < .0001). Conclusions: Structural changes similar to emphysema are also present in asthmatic children. Our findings suggest that the persistence of increased RV may be used to identify subjects with low-density areas on HRCT. (J Pediatr 2002;141:104-8)
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
Serum lactate-dehydrogenase isoenzymes in HIV positive children. A longitudinal study
No full textThe impairment of humoral immunity with rapid turn-over of cellular B clones in children with HIV infection is known as well as the conduct of LDH isoenzymes in B cell lymphoproliferative diseases like Burkitt's lymphoma. Therefore, serum lactate-dehydrogenase activity (LD, EC 1.1.1.27) and its isoenzymes have been evaluated twice (within 12 months) in 11 children with HIV infection with respect to a control group (30 subjects). Furthermore, the relationship between those and other clinical and immunologic parameters (total lymphocytes, CD4/CD8, immunoglobulins, classification according to the Atlanta CDC 1987) has been studied. HIV infected children have shown a significant decrease in LD1 rates, which was directly correlated to CD4/CD8 values. After the follow-up, this correlation became even more significant. Thus, these findings may suggest the usefulness of LDH isoenzymes evaluation as a marker of disease activity in children with HIV infection
Analisi del battito ciliare nella discinesia ciliare tramite algoritmi di motion detection
No full textLactate dehydrogenase isoenzymes in HIV-positive children
No full textConsidering that in the HIV infection there is a precocious deterioration of humoral immunity with rapid turn-over of cellular B clones, we have evaluated the conduct of serum lactate-dehydrogenase activity (LD, EC 1.1.1.27) and its isoenzymes in 21 children born from HIV-positive mother respect to a control group (30 subjects). Furthermore we have checked the existence of a probable correlation between those and other clinical and immunologic parameters (total lymphocytes, CD4/CD8, immunoglobulins, classification according to the Atlanta CDC). In seropositive children we saw, respect to those evolved towards P3 stage, a significantly raising of LD4 (also vs. control group) for likely pulmonary parenchyma's damage, LD3 for B immature lymphocytes' increase and a reduction of LD1 (also vs. control group) for mature clones' decrement. Furthermore in seropositive subjects there was the existence of a direct correlation between LD1 and CD4/CD8 values. As such, the evaluation of LD isoenzymes can establish an useful element in the clinical monitoring of seropositive children
- …
