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La ricerca chimico tossicologica sistematica generica in tossicologia forense: nota I : considerazioni sulle metodiche di saggio gas cromatografico da applicare nella ricerca chimico tossicologica generica
No full textThe retention indices for 230 substances of interest in toxicology were determined on SE30, OV1 and OV17 and 60 were determined on QF1 in isothermal conditions at 180°. The data for a hundred or so substances were then statistically compared between themselves when possible (SE30 and OV1) and with the findings obtained by Kazjak and Permisohn. In general, no statistically significant deviations were found in the series compared except for the data on QF1 where the method used to calculate the retention index, however, was known not to guarantee correct results. Statistical analysis indicated that the data for gas chromatographic mobility, expressed as I(R), were reproducible to a good degree, even when the assays were carried out in different laboratories. This means that mobility, expressed as I(R), is of considerable diagnostic value. Using the I(R) value in general gas chromatographic chemical toxicological investigations, the field of investigation can rapidly be restricted to a very limited number of substances. Since the I(R) has proved satisfactorily repeatable, it may be used not only for data from the local laboratory, but also for findings supplied by other workers
La ricerca chimico tossicologica sistematica generica in tossicologia forense. II: considerazioni sull’uso degli indici di ritenzione e dei Δ IR nelle metodiche di saggio gas cromatografico
No full textValues for IR (retention index) and ΔIR (difference between the IR values of a given substance obtained on 2 columns of different polarity) were detd. for ∼50 compds. (mostly drugs) of interest in forensic toxicol., using isothermal conditions at various temps. (120-260°) and with programmed temp. cycles. The column packings used were OV1 and OV17 on Gas-Chrom Q. In general, the ΔIR values were as reproducible as the IR. Both showed little or no dependence on the exptl. conditions under which they were obtained. The ΔIR, which measures the polarity of a compd., may be a significant anal. tool in examg. homogeneous series of substances. The IR, however, esp. if detd. under programmed temp. conditions, may be of more value in detg. the genetic nature of heterogeneous compds. such as those of interest in toxicol. By the methods described here, compds. with IR values of the order of 3000 can be detd
Systematic, generic, chemicotoxicological research in forensic toxicology. Part III. Comparison of IR and ΔIR obtained under programmed and isothermal temperature conditions
No full textGas-chromatog. data are presented on ∼350 drugs of forensic-toxicol. interest. These data are mainly the retention index (IR) values obtained on OV1 and OV17 columns under programmed and isothermal temp. conditions and the differences (ΔIR) obtained for the individual substances on the 2 columns. Use of the IR to express gas-chromatog. mobility gave well-reproducible data, with respect to both variations in temp. and comparison of values obtained from different labs. Taken alone, the ΔIR has low power for identifying a compd., but when used together with the IR values it constitutes a useful element for further narrowing the possibilities. The use of IR as a new approach to gas-chromatog. investigations in forensic toxicol. is suggested
Chemical-toxicological diagnosis in 16 cases of "intravenous narcotism" deaths
No full textThe chemical-toxicological diagnosis aspects involved in 16 cases of "intravenous narcotism" deaths are discussed. Liquids and biological materials were directly tested by RIA, GLC and TLC. According to the Authors, RIA is assumed to be more speedy and more sensitive than traditional chemical technics. Therefore RIA is proposed for quantitative determination of morfina and its derivates in biological liquids and viscera, previous the qualitative confirmation by the chemical tests
Systematic generic chemico-toxicological research in forensic toxicology. III. Comparison of IR and delta IR obtained under programmed and under isothermic conditions
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
La ricerca chimo-tossicologica sistematica generica in tossicologia forense. Nota IV : la standardizzazione in cromatografia su strato sottile
No full textResearch has been done to determine whether in the field of general chemical-toxicology, TLC can be used to mobility data which are as satisfactorily reproducible as those obtained with GLC. Correct mobility data were calculated using four reference compounds to provide reference values for each real fraction of the chromatographic process. The statistical evaluation of the reproducibility of the mobility data, both corrected and absolute, was made on values calculated in 10 different laboratories for both acid and alkaline substances appearing in the list of dangerous drugs. Since the corrected mobility data proved satisfactorily reproducible, it is suggested that this technique may help in the rationalization of chemical-toxicological research
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