1,721,109 research outputs found
Enzymatic Boolean Logic Gates toward ON/OFF Sensing
No full textIn this paper we report a combined theoretical and experimental approach to develop enzyme logic gates networks (ELGN). ELGNs were tested in solution with optical analysis of the output signals. Then, the enzymes were immobilized on a buckypaper electrode for electrochemical transduction of the output signals. Finally, the switchable electrodes were integrated in a biofuel cell as a self-powered device for the detection of sucrose in adulterated wine samples
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
Reciprocal changes of serum thyroglobulin and TSH in residents of a moderate endemic goiter area
No full text
Insulin autoimmune syndrome (Hirata disease): A comprehensive review fifty years after its first description
No full textInsulin autoimmune syndrome (IAS), also named Hirata’s disease, is a rare condition characterized by hypoglycemic episodes due to the presence of high titers of insulin autoanti-bodies (IAA). IAS is a form of immune-mediated hypoglycemia, which develops when a triggering factor (ie, a medication or a viral infection) acts on an underlying predisposing genetic background. IAS pathogenesis involves the formation of insulin-IAA complexes that induce glycemic alterations with a double-phase mechanism: IAA prevent insulin to bind its receptor in the postprandial phase, possibly resulting in mild hyperglycemia; thereafter, insulin is released from the complexes irrespective of blood glucose concentrations, thus inducing hypo-glycemia. The diagnosis of IAS is challenging, requiring a careful workup aimed at excluding other causes of hyperinsulinemic hypoglycemia. The gold standard for the definitive diagnosis is the finding of IAA in a blood sample. Because IAS is frequently a self-remitting disease, its management mostly consists of supportive measures, such as dietary modifications, aimed at preventing the development of hypoglycemia. Pharmacological therapies may occasionally be necessary for patients presenting with severe manifestations of IAS. Available therapies may include drugs that reduce pancreatic insulin secretion (somatostatin analogues and diazoxide, for instance) and immunosuppressive agents (glucocorticoids, azathioprine and rituximab). The purpose of this review is to provide a comprehensive analysis of the disease, by describing the burden of knowledge that has been obtained in the 50 years following its first description, took in 1970, and by highlighting the points that are still unclear in its pathogenesis and management
Self-powered logically operated fluorescent detection of hepatitis B virus (HBV)
No full textIn this study, a novel sensing strategy based on double sensing/actuating pathway is demonstrated, being capable to trigger the DNA-based AND gate for the sensitive and selective detection of hepatitis B virus DNA (HBV-DNA). Such an approach encompasses an enzymatic machinery logically operated using the variation of physiologically relevant biomarkers for liver dysfunctions. Alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) are used as inputs of an AND gate generating an output signal, namely lactate. In particular, lactate is oxidized back to pyruvate at the anodic electrode by lactate oxidase connected in mediated electron transfer through ferrocene moieties (creating an amplifying recycling mechanism). The anodic electrode is further connected with a Myrothecium verrucaria bilirubin oxidase (MvBOx) based biocathode modified with SiO2 nanoparticles (SiO2NPs) functionalized with phenyl boronic acid and trigonelline, triggering the release of quenching DNA (qDNA) upon local pH change at the electrode surface (notably, modified SiONPs gets negatively recharged upon local pH gradient releasing negatively charged DNA). Next, the released qDNA labeled with BHQ2 and detecting DNA (dDNA, labeled with FAM) are detecting HBV-DNA. The proposed biosensor can discriminate between the absence and presence of HBV-DNA setting the threshold at 0.05 fM in model buffer solutions and 1 fM in human serum. This enzymatic/DNA logic network can be of particular interest for future biomedical applications (e.g., early detection of liver cancer disease etc.). In the future development this technology could be easily integrated with a smartphone camera, allowing more user-friendly applications
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