1,720,977 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
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
Memantine agonist action at dopamine D2High receptors
Full text linkMemantine is reported to improve symptoms in moderate cases of Alzheimer´s disease and Parkinson´s disease, but is also known to trigger psychosis in some Parkinson patients. Because these clinical features suggested a possible dopamine component of memantine action, we measured the potency of memantine on the functional high-affinity state of dopamine D2 receptors, or D2(High). Using [(3)H]domperidone to label D2 receptors, the memantine dissociation constant at D2(High) was 917 +/- 23 nM for rat striatal D2 receptors and 137 +/- 19 nM for human cloned D2Long receptors. The memantine dissociation constant for striatal N-methyl-D-aspartate (NMDA) receptors labeled by [(3)H]MK 801 was 2200 +/- 400 nM. Memantine stimulated the incorporation of [(35)S]GTP-gamma-S into D2-expressing Chinese Hamster Ovary cells with a dissociation constant of 1200 +/- 400 nM. Memantine, between 200 and 2000 nM, directly acted on D2(High) to inhibit the release of prolactin from isolated anterior pituitary cells in culture. Because the memantine potencies at NMDA receptors and dopamine D2(High) receptors are of a similar order of magnitude, it is likely that the clinical features of memantine can be attributed to its action at both types of receptors.Fil: Seeman, Philip. University of Toronto; CanadáFil: Caruso, Carla Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Lasaga, Mercedes Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; Argentin
Dopamine partial agonist actions of the glutamate receptor agonists LY 354,740 and LY 379,268
Full text linkBecause glutamate compounds alter the release of dopamine and prolactin, the present study examined whether group II metabotropic receptor agonists, LY 354,740 and LY 379,268, had any direct in vitro action on dopamine D2 receptors on rat striatal tissue, cloned D2Long receptors, and prolactin release from anterior pituitary cells. In competition versus the D2-specific ligand [(3)H]domperidone, LY 354,740 had a dissociation constant of 24 nM at D2(High) (the functional high-affinity state of dopamine D2 receptors), while the value for LY 379,268 was 21 nM. LY 354,740 also stimulated by 50% the incorporation of [(35)S]-GTP-gamma-S at a concentration of 120 nM, but its maximal stimulation was only 22% of the maximum elicited by dopamine. LY 379,268 stimulated by 50% the incorporation of [(35)S]-GTP-gamma-S at 280 nM, but its maximal stimulation was also only 22% of the maximum elicited by dopamine. However, both LY 354,740 and LY 379,268 potently inhibited the dopamine-induced incorporation of [(35)S]-GTP-gamma-S with inhibitory Ki values of 43 nM and 30 nM, respectively. The release of prolactin from rat isolated anterior pituitary cells in culture was 50% inhibited by 20 nM LY 379,268 and by 100 nM LY 354,740. These Ki values are similar to those known for the mGluR II receptor, suggesting that these compounds may have both glutamate and dopamine actions in vivo. The dopamine agonist and antagonist actions of these compounds indicate that these drugs have properties of a dopamine partial agonist, and may, therefore, have antipsychotic action.Fil: Seeman, Philip. University of Toronto; CanadáFil: Caruso, Carla Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Lasaga, Mercedes Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; Argentin
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
Upregulation of CaMKIIβ and Nogo-C mRNA in Schizophrenia and the Prevalence of CAA Insert in the 3’UTR of the Nogo Gene
No full textSchizophrenia may result from altered gene expression leading to abnormal neurodevelopment. In a search for genes with altered expression in schizophrenia, cDNA library subtractive hybridization experiments using post-mortem human frontal cerebral cortices from schizophrenia individuals and neurological controls were performed.
I found the mRNA of two neurodevelopmentally important genes, Nogo (RTN4) and calcium/calmodulin-dependent protein kinase II beta (CaMKIIβ), to be overexpressed in post-mortem frontal cortex tissues from patients who suffered with schizophrenia. I used the quantitative real-time polymerase chain reaction method to determined the mRNA levels of these genes in tissues from age- and sex-matched individuals.
Nogo is a myelin-associated protein which inhibits the outgrowth of neurites and nerve terminals. The gene produces three splice variants, Nogo-A, B and C. I found Nogo-C mRNA to be overexpressed by 26% in schizophrenia. I also found a 17% reduction of Nogo-B mRNA in samples from individuals who had been diagnosed with severe depression. Furthermore, I showed that there is a direct correlation between the expression of both Nogo-A and -C and the presence of a CAA insert in the 3’UTR of the Nogo gene.
CaMKII is a kinase localized at the postsynaptic density. The holoenzyme is primarily composed of the subunits α and β, encoded by two separate genes. It influences the expression of many neuroreceptors, in particular receptors of the glutamatergic pathway. CaMKII also mediates neural maturation during puberty, a time of onset of schizophrenia. The expression of CaMKIIα was elevated 29% in frontal cortex tissues of patients who suffered from depression. The expression of CaMKIIβ was elevated 27% in tissues of schizophrenia patients and 36% in tissues of patients diagnosed with depression. Upregulation of CaMKIIβ was associated with the presence of the CAA insert in at least one copy of the Nogo gene in a group containing both healthy subjects and patients with mental illness, possibly linking the CaMKII and Nogo pathways. The values for the expression of Nogo, CaMKIIα and CaMKIIβ were normalized to β-glucuronidase expression to minimize the effects of mRNA degradation. These results confirm that upregulation of Nogo-C and CaMKIIβ is likely associated with schizophrenia.Ph
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