1,721,066 research outputs found
Effect of FRP mesh reinforcement on shear capacity and deformability of masonry walls
The research deals with the analysis of the structural behaviour of CFRP (rebars) reinforced masonry panel. The study shows also the comparison between the behavior of plain masonry and masonry reinforced with ordinary mesh steel under shear test. The tests were carried out using the diagonal test; two different types of wall were employed (but with the same mechanical characteristics of materials) with 200 mm and 330 mm of thickness, using the steel mesh reinforcement and carbon FRP rebars on both sides. The sample was made with mortar applied directly to the face, with the reinforcement inside. Finally the research makes a comparison with a similar test carried out by other authors using FRP strips and lamina
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
Implementation and performance evaluation of a database of chemical formulas for the screening of pharmaco/toxicologically relevant compounds in biological samples using electrospray ionization-time-of-flight mass spectrometry
Electrospray ionization (ESI)-time-of-flight (TOF) MS enables searching a wide number of pharmaco/toxicologically relevant compounds (PTRC) in biosamples. However, the number of identifiable PTRC depends on extension of reference database of chemical formulas/compound names. Previous approaches proposed inhouse or commercial databases with limitations either in PTRC number or content (e.g., few metabolites, presence of non-PTRC). In the frame of development of a ESI-TOF PTRC screening procedure, a subset of PubChem Compound as reference database is proposed. Features of this database (approximately 50 500 compounds) are illustrated, and its performance evaluated through analysis by capillary electrophoresis (CE)-ESI-TOF of hair/blood/urine collected from subjects under treatment with known drugs or by comparison with reference standards. The database is rich in parent compounds of pharmaceutical and illicit drugs, pesticides, and poisons and contains many metabolites (including about 6 000 phase I metabolites and 180 glucuronides) and related substances (e.g., impurities, esters). The average number of hits with identical chemical formula is 1.82 ± 2.27 (median = 1, range 1-39). Minor deficiencies, redundancies, and errors have been detected that do not limit the potential of the database in identifying unknown PTRC. The database allows a much broader search for PTRC than other commercial/in-house databases of chemical formulas/compound names previously proposed. However, the probability that a search retrieves different PTRC having identical chemical formula is higher than with smaller databases, and additional information (anamnestic/circumstantial data, concomitant presence of parent drug and metabolite, selective sample preparation, liquid chromatographic retention, and CE migration behavior) must be used in order to focus the search more tightly. © 2008 American Chemical Society
First application of atmospheric-pressure chemical ionization gas chromatography tandem mass spectrometry to the determination of cannabinoids in serum.
The analysis of cannabinoids in blood samples is still a challenging issue for forensic laboratories, because of the low concentrations to be determined to prove that a person acted under CannabisTherefore, sensitive analytical techniques are required. This study presents the development and validation of a novel APGC-MS/MS method for the simultaneous determination of Δ9-tetrahydrocannabinol (THC), 11-hydroxy- Δ9-THC (THC-OH), 11-nor-9-carboxy- Δ9-THC (THCA), cannabidiol (CBD), cannabidiol acid (CBDA) and cannabigerol (CBG) in human serum. The developed method was fully validated according to international guidelines, with evaluation of selectivity, precision, accuracy, linearity, LODs and LOQs, extraction recovery and matrix effect. The method was linear in the range 0.2-25 ng/mL for THC, THC-OH, CBD and CBG, while for THCA and CBDA linearity was assessed in the range of 0.8-100 ng/mL and 3-100 ng/mL, respectively. The LOQs were determined in 0.2 ng/mL for THC, 0.4 ng/mL for THC-OH, 0.8 ng/mL for CBD and CBG, 1.6 ng/mL for THCA and 3 ng/mL for CBDA. The method was applied to the analysis of 15 serum samples from DUID cases. To the best of our knowledge, the present work is the first one describing an application of APGC source in the field of forensic toxicology
Rapid optimized separation of bromide in serum samples with capillary zone electrophoresis by using glycerol as additive to the background electrolyte
After decades of neglect, bromide has recently been re-introduced in therapy as an effective anti-epileptic drug. The present paper describes the methodological optimization and validation of a method based on capillary zone electrophoresis for the rapid determination of bromide in serum using a high-viscosity buffer and a short capillary (10 cm). The optimized running buffer was composed of 90 mM sodium tetraborate, 10 mM sodium chloride, pH 9.24 and 25% glycerol. The separation was carried out at 25 kV at a temperature of 20 °C. Detection was by direct UV absorption at 200 nm wavelength. The limit of detection (signal-to-noise ratio = 5) in serum was 0.017 mM. The precision of the method was verified in blank serum samples spiked with bromide, obtaining intra-day and day-to-day tests, relative standard deviation values ≤0.2% in terms of migration times and values <2% in terms of peaks areas, respectively
Appropriate Similarity Measures for Author Cocitation Analysis
We 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
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