1,720,976 research outputs found
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
In vitro pharmacological characterisation of a novel cyclic nociceptin/orphanin FQ analogue c[Cys(7,10)]N/OFQ(1-13)NH2
No full textNociceptin/orphanin FQ (N/OFQ) is the endogenous 17 amino acid peptide ligand for the Gi-protein-coupled N/OFQ receptor (NOP). In an attempt to improve the metabolic stability of N/OFQ, we have produced a truncated cyclic analogue with cysteine residues at positions 7 and 10, c[Cys7,10]N/OFQ(1-13)NH2 (c[Cys7,10]). c[Cys7,10], the template N/OFQ(1-13)NH2 and N/OFQ displaced the binding of [3H]N/OFQ to Chinese hamster ovary cells expressing recombinant human NOP (CHOhNOP) with pK i values of 9.98, 9.83 and 9.18, respectively. In addition, c[Cys7,10], N/OFQ(1-13)NH2 and N/OFQ stimulated the binding of guanosine triphosphate gamma [35S] to CHOhNOP cells with pEC50/E max (stimulation factor) of 9.16/5.5, 9.11/4.9 and 8.35/5.5, respectively. c[Cys7,10], N/OFQ(1-13)NH2 and N/OFQ inhibited forskolin-stimulated cyclic adenosine monophosphate (cAMP) formation with pEC50 values of 10.08, 10.11 and 9.78, respectively. All ligands produced complete inhibition of cAMP formation. In both functional assays, c[Cys7,10] was a full agonist. In a series of metabolism experiments, incubation of 1 nM c[Cys7,10], N/OFQ(1-13)NH2 and N/OFQ with a rat brain homogenate produced a time-dependent loss of peptide that was greatest for the native peptide N/OFQ. Amidation in N/OFQ(1-13)NH2 produced some metabolic protection, but this was not significantly improved by further inclusion of c[Cys7,10]. In summary, c[Cys7,10] is a high-affinity, high-potency full agonist of the NOP receptor. However, we were unable to demonstrate clear metabolic protection
Effects of [(pF)Phe(4)]nociceptin/orphanin FQ-(1-13)NH2 on GTP gamma S-35 binding and cAMP formation in Chinese hamster ovary cells expressing the human nociceptin/orphanin FQ receptor
No full textNociceptin/orphanin FQ (N/OFQ) is the endogenous ligand for the N/OFQ receptor (NOP). In this study using Chinese hamster ovary
(CHO) cells expressing the human NOP (CHOhNOP) and GTPg35S binding and cAMP inhibition assays, we have characterised a novel N/
OFQ ligand, [( pF)Phe4]N/OFQ-(1–13)NH2, ([( pF)Phe4]). [( pF)Phe4] was produced by insertion of a fluorine atom into the para position of
the phenyl ring of Phe4 of the truncated N/OFQ peptide N/OFQ-(1–13)NH2. In CHOhNOP membranes [( pF)Phe4] and N/OFQ-(1–13)NH2
stimulated GTPg35S binding with pEC50 (meanFS.E.M.) values of 9.55F0.01 and 8.94F0.5 ( P < 0.05), respectively. In whole CHOhNOP
cells [( pF)Phe4] and N/OFQ-(1–13)NH2 inhibited forskolin stimulated cAMP formation with pEC50 values of 10.19F0.06 and 9.60F0.04,
respectively ( P < 0.05). [( pF)Phe4] was more potent (f4 fold) than N/OFQ-(1–13)NH2. In both assays, the effects of [( pF)Phe4] and N/
OFQ-(1–13)NH2 were pertussis toxin sensitive and reversed by the NOP antagonists J-113397 (pA2/pKB values 7.89–8.53) and III-BTD
(pA2/pKB values 7.27–7.96). [( pF)Phe4] is therefore a potent full agonist at NOP receptors that will be useful as pharmacological tool for
defining the role of N/OFQ–NOP system in health and disease
Partial agonist behaviour depends upon the level of nociceptin/orphanin FQ receptor expression - studies using the ecdysone inducible mammalian expression system
Full text link(1) Partial agonism is primarily dependent upon receptor density and coupling efficiency. As these parameters are tissue/model dependent, intrinsic activity in different tissues can vary. We have utilised the ecdysone-inducible expression system containing the human nociceptin/orphanin FQ (N/OFQ) peptide receptor (hNOP) expressed in Chinese hamster ovary cells (CHOINDhNOP) to examine the activity of a range of partial agonists in receptor binding, GTPgamma35S binding and inhibition of adenylyl cyclase studies. (2) Incubation of CHOINDhNOP cells with ponasterone A (PON) induced hNOP expression ([leucyl-3H]N/OFQ binding) of 24, 68, 191 and 1101 fmol mg-1 protein at 1, 2, 5 and 10 microm PON, respectively. At 191 fmol mg-1, protein hNOP pharmacology was identical to that reported for other traditional expression systems. (3) pEC50 values for GTPgamma35S binding ranged from 7.23 to 7.72 (2-10 microm PON) for the partial agonist [Phe1psi(CH2-NH)Gly2]N/OFQ(1-13)-NH2 ([F/G]N/OFQ(1-13)-NH2) and 8.12-8.60 (1-10 microm PON) for N/OFQ(1-13)-NH2 and Emax values (stimulation factor relative to basal) ranged from 1.51 to 3.21 (2-10 microm PON) for [F/G]N/OFQ(1-13)-NH2 and 1.28-6.95 (1-10 microm) for N/OFQ(1-13)-NH2. Intrinsic activity of [F/G]N/OFQ(1-13)-NH2 relative to N/OFQ(1-13)-NH2 was 0.3-0.5. [F/G]N/OFQ(1-13)-NH2 did not stimulate GTPgamma35S binding at 1 microm PON, but competitively antagonised the effects of N/OFQ(1-13)-NH2 with a pKB=7.62. (4) pEC50 values for cAMP inhibition ranged from 8.26 to 8.32 (2-10 microm PON) for [F/G]N/OFQ(1-13)-NH2 and 9.42-10.35 for N/OFQ(1-13)-NH2 and Emax values (% inhibition) ranged from 19.6 to 83.2 for [F/G]N/OFQ(1-13)-NH2 and 40.9-86.0 for N/OFQ(1-13)-NH2. The intrinsic activity of [F/G]N/OFQ(1-13)-NH2 relative to N/OFQ(1-13)-NH2 was 0.48-0.97. (5) In the same cellular environment with receptor density as the only variable, we show that the profile of [F/G]N/OFQ(1-13)-NH2 can be manipulated to encompass full and partial agonism along with antagonism
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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