1,720,960 research outputs found
Role of fine needle aspiration cytology in the preoperative evaluation of smooth muscle tumors
No full textI.F. 0.93
On phosphotungstic acid staining. IV. Selectivity of the staining reaction
No full text Phosphotungstic acid was used at different hydrogen ion concentrations and combined with glycogen and lysozyme, which were used as model systems for carbohydrates and proteins, respectively. Furthermore, in order to correlate the chemical analysis with the selectivity of the "staining" reaction, ultrastructural studies were carried out using mouse skin, aorta, esophagus and colon. When the heteropolyacid was used at a pH around 1.0, and not above 1.8, there was no interaction with glycogen whereas an extremely high lysozyme binding ensued. At these levels of hydrogen ion concentration the selectivity of the staining was quite apparent. The rise in pH of the phosphotungstic acid solutions determined a loss of specificity in the staining reaction accompanied by a consistent glycogen uptake. This anomalous reaction was interpreted as the result of a decomposition of the metal into two altogether different chemical compounds: phospho-11-tungstic acid and free tungstates. The latter, like the molybdates, are known to be excellent complexing agents with carbohydrates. </jats:p
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
Design and Implementation of a DVB-S2 Reconfigurable Datapath BCH Encoder for High Data-Rate Payload Data Telemetry
No full textTo ensure the flexibility of Earth Observation satellite missions, it is essential to have highly adaptable communication systems equipped with efficient modulation and coding schemes. The preferred approach for such applications is the DVB-S2 standard, which provides three operational modes: Constant Coding and Modulation, Variable Coding and Modulation, and Adaptive Coding and Modulation. Additionally, this standard incorporates a robust Forward Error Correction system that combines a Low-Density Parity-Check encoder with a Bose-Chaudhuri-Hocquenghem encoder. This combination ensures optimal utilization of channel bandwidth while maintaining an acceptable Bit Error Rate throughout the satellite’s orbit. This research is centred on designing and implementing a highly flexible and high-speed parallel Bose-Chaudhuri-Hocquenghem encoder, fully compliant with the DVB-S2 standard, and supporting all Constant Coding and Modulation, Variable Coding and Modulation, and Adaptive Coding and Modulation modes. In contrast to existing solutions, our proposed encoder permits the concurrent processing of a larger number of bits, thereby enhancing parallelism. Furthermore, parallelism is a configurable parameter, allowing seamless system scalability. The proposed encoder can be tailored to accommodate a wide range of throughput requirements, making it suitable for various mission classes. This flexibility enables users to balance factors like complexity, power consumption, and performance. The hardware platform selected for circuit implementation is the space-grade Xilinx XQRKU060 FPGA. Our results demonstrate a maximum achievable throughput ranging from 600 Mbps to 19.2 Gbps and a dynamic power consumption of 10 mW to 79 mW, depending on the chosen parallelism level (ranging from 2 to 96). The optimization of resource utilization is particularly noteworthy, as it reduces the required resources to as low as 760 Look-up Tables and 344 registers for lower parallelism levels
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
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