186,272 research outputs found
Crosslinker effects on functional properties of alginate/N-succinylchitosan based hydrogels
No full textIn this paper, physico-chemical, mechanical and antimicrobial properties of hydrogels based on alginate/N-succinylchitosan blends crosslinked by calcium or zinc ions containing cellulose microfibers were investigated and discussed. With respect to plain alginate hydrogels, the addition of N-succinylchitosan significantly improved properties such as swelling degree and stability in saline solution. The water vapour transmission rate confirmed that all the hydrogels were able to assure a moist wound environment. Morphological analysis showed a good embedding of fibres within the zinc crosslinked hydrogels. In addition, zinc-crosslinked hydrogels evidenced antimicrobial activity against two common skin pathogenic bacteria, Staphylococcus aureus and Escherichia coli. Cytotoxicity assays proved that the amount of zinc released is slightly over the toxic level. Overall, the characteristics of the zinc-crosslinked hydrogels showed their potential interest as materials for wound dressing
Cytological features of micropapillary and plasmacytoid variants of urothelial carcinoma
No full textBackground: Micropapillary and plasmacytoid variants of urothelial carcinoma (UC) exhibit very aggressive clinical behavior. To date, only a small number of cytology cases have been reported in either of these variants. Herein, we report 15 cases of UC with combined micropapillary and plasmacytoid features based on urine cytology. Methods: We performed a retrospective analysis of all patients with carcinoma of bladder with predominant plasmacytoid and micropapillary histology who had been seen from 2005 to 2017. A total of 15 cases (six cases of plasmacytoid variant and nine cases of micropapillary variant of bladder cancer) with urine specimen were evaluated. The cytomorphological features were compared between two histological variants. Results: Fifteen urine cytology cases with the diagnosis of high-grade UC were investigated. The ratio man to women was 5:1 with a median age of 79 years (range: 72-90 years). Single-cell pattern, flat sheets, three-dimensional clusters, micropapillae, nuclear grade, cytoplasmic vacuoles, and necrosis, were evaluated in urine samples of micropapillary variant. The cytological features of plasmacytoid are characterized by large, discohesive, isolated tumor cells that have abundant, thick cytoplasm, and eccentrically located, hyperchromatic nuclei with coarse chromatin and inconspicuous nucleoli. Conclusion: It is important to recognize the cytological characteristics of these uncommon but aggressive entities to determine a precise diagnosis. Attention to morphological features, together with clinical history and appropriate immunohistochemical studies may be useful to urologist in pre-operative planning and may lead to a more aggressive surgical approach
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Mitigation of Random Query String DoS via Gossip
No full textThis paper presents a mitigation scheme to cope with the random query string Denial of Service (DoS) attack, which is based on a vulnerability of current Content Delivery Networks (CDNs), a storage technology widely exploited to create reliable large scale distributed systems and cloud computing system architectures. Basically, the attack exploits the fact that edge servers composing a CDN, receiving an HTTP request for a resource with an appended random query string never saw before, ask the origin server for a (novel) copy of the resource. This request to the origin server is made also if the edge server contains a copy of the resource in its storage. Such characteristics can be employed to take an attack against the origin server by exploiting edge servers. In fact, the attacker can send different random query string requests to different edge servers that will overload the origin server with simultaneous (and unneeded) requests. Our strategy is based on the adoption of a simple gossip protocol, executed by edge servers, to detect the attack. Based on such a detection, countermeasures can be taken to protect the origin server, the CDN and thus the whole distributed system architecture against the attack. We provide simulation results that show the viability of our approach
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Reseña de Adelstein, Andreina; Bernal, Elisenda; Sinner, Carsten. 2019. Clases y categorías en la formación de palabras en español. Julieta Straccia
No full textCytologic Diagnosis of Oncocytic Neoplasms of the Thyroid Gland: The Importance of the Clinical Scenario.
No full textCytologic Diagnosis of Oncocytic Neoplasms of the Thyroid Gland: The Importance of the Clinical Scenario
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
No full textWe 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
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