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Effects of the novel NMDA receptor antagonist, CGP 39551, on field potentials and the induction and expression of LTP in the dentate gyrus in vivo
No full textThe effects of the novel competitive N-methyl-D-aspartate (NMDA) receptor antagonist, CGP 39551 [the carboxyethylester of CGP 37849; DL-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid], on extracellular field potentials and long-term potentiation (LTP) induced in the dentate gyrus by stimulation of the perforant path were studied in anesthetized rats. CGP 39551 attenuated the population spike (PS) and excitatory postsynaptic potential (EPSP) amplitude of dentate field potentials, reduced the NMDA receptor-mediated component of train-evoked burst potentials, and prevented the induction of LTP. The decrease in PS and EPSP amplitude produced by CGP 39551 was observed mainly in non-potentiated synaptic populations; potentiated field potentials were only minimally affected by drug treatment. These results are consistent with receptors may contribute in a tonic manner to the state of dentate granule cell excitability. Finally, the differential modulation of potentiated and non-potentiated synapses by CGP 39551 suggests that a change in some properties of postsynaptic AMPA receptors is involved in the expression of LTP.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56202/1/marenSYN92.pd
Effect of developmental NMDAR antagonism with CGP 39551 on aspartame-induced hypothalamic and adrenal gene expression - Fig 2
No full text(A) Venn diagram representation of hypothalamic DEGs in ASP, CGP and ASP+CGP groups relative to Control. The numbers marked in the diagram indicate the number of genes significantly up regulated (upward arrows) and down regulated (downward arrows). (B) Top 12 canonical pathways derived from Ingenuity Pathway Analysis in hypothalamus of ASP-exposed mice. The stacked bar chart displays the percentage of genes that were upregulated (red), downregulated (green) and genes not overlapping in dataset (white) in each canonical pathway. Significance level is scored as–log(p-value) from Fischers exact test. The numerical value at the ends of each bar represents the total number of genes in the canonical pathway. CGP denotes developmental NMDAR antagonism with CGP 39551; ASP denotes chronic exposure to aspartame; ASP+CGP denotes chronic aspartame exposure and developmental NMDAR antagonism with CGP 39551.</p
Effect of developmental NMDAR antagonism with CGP 39551 on aspartame-induced hypothalamic and adrenal gene expression - Fig 4
No full text(A) Venn diagram representation of adrenal DEGs in ASP, CGP and ASP+CGP groups relative to Control. The numbers marked in the diagram indicate the number of genes significantly up regulated (upward arrows) and down regulated (downward arrows). CGP denotes developmental NMDAR antagonism with CGP 39551; ASP denotes chronic exposure to aspartame; ASP+CGP denotes chronic aspartame exposure and developmental NMDAR antagonism with CGP 39551. Top 12 canonical pathways derived from Ingenuity Pathway Analysis in adrenal glands when exposed to (B) Aspartame (C) developmental antagonism with CGP and (D) ASP + CGP. The stacked bar chart displays the percentage of genes that were upregulated (red), downregulated (green) and genes not overlapping in dataset (white) in each canonical pathway. Significance level is scored as–log(p-value) from Fischers exact test. The numerical value at the ends of each bar represents the total number of genes in the canonical pathway.</p
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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
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