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    The effect of pH and D-glycerate 2,3-bisphosphate on the O2 equilibrium of normal and SH(beta 93)-modified human hemoglobin

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    The present paper reports data for the effect of pH and D-glycerate 2,3-bisphosphate (D-glycerate-2,3-P2) on the oxygen equilibrium of normal and SH(beta 93)-modified human hemoglobin. At sufficiently high D-glycerate-2,3-P2 concentrations, both oxy and deoxy forms of HbA are saturated with the organic phosphate at all pH values between 6 and 9. Furthermore the difference in the affinity for D-glycerate-2,3-P2 between deoxy and oxy hemoglobin remains constant with pH, implying that the pK values of the Bohr effect groups in deoxy and oxyhemoglobin are not affected by the presence of D-glycerate-2,3-P2 on the hemoglobin molecule. In the hemoglobins modified in position beta 93, the difference in affinity between deoxy and oxy hemoglobin for D-glycerate-2,3-P2 decreases with decrease in pH due mainly to a decrease in the affinity of the deoxy form for D-glycerate-2,3-P2. The effect of the chemical modification appears to be primarily a change in pK of a Bohr group in deoxy hemoglobin which is especially pronounced in the presence of phosphates

    Stabilization of the T-state of ferrous human adult haemoglobin by chlorpromazine and trifluoperazine

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    In the present study, the effect of the neuroleptics chlorpromazine (2-chloro-N,N-dimethyl-10H-phenothiazine-10-propanamine) and trifluoperazine {10-[3-(4-methylpiperazin-1-yl)-propyl]-2-(trifluoromethyl)-10H-phenothiazine} on the EPR-spectroscopic properties of ferrous human adult nitrosylated haemoglobin (HbNO) is reported. Addition of the two drugs to HbNO shifted the conformational equilibrium from the high- to the low-affinity form of the ligated tetramer, as observed for 2,3-D-glycerate bisphosphate, the physiological modulator of haemoglobin action. The effect of chlorpromazine and trifluoperazine on the EPR-spectroscopic properties of HbNO was enhanced by inositol hexakisphosphate. The binding of neuroleptics to ferrous human adult haemoglobin may represent an important undesirable side effect. In fact, oxygen affinity for ferrous human adult haemoglobin decreases on increasing chlorpromazine and trifluoperazine concentration, In addition, red blood cells may act as neuroleptic scavengers

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

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    “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

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    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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