1,720,954 research outputs found
Exploring transgenerational inheritance in epigenotypes of DAT heterozygous rats: circadian anomalies and attentional vulnerability
Get PDF: Dopamine (DA) is mainly involved in locomotor activity, reward processes and maternal behaviors. Rats with KO gene for dopamine transporter (DAT) coding for a truncated DAT protein are in hyperdopaminergic conditions and develop stereotyped behaviors and hyperactivity. Our aim was to test the prior transgenerational modulation of wild and truncated allele as expressed in heterozygous DAT rats: specifically we addressed the possible sequelae due to genotype and gender of the ancestors, with regard to behavioral differences in F1, F2, F3 rats. We studied non-classical DAT heterozygotes based on two specular lines, with putative grand-maternal vs. grand-paternal imprinting. MAT females (F1; offspring of KO male and WT female) mated with a KO male to generate MIX offspring (F2). Specularly, PAT females (F1; offspring of KO female and WT male) mated with a KO male to generate PIX offspring (F2). Similarly to PAT, we obtained MUX (F2; HET offspring of MAT sire and KO dam); we also observed the F3 (MYX: HET offspring of KO male and MUX female, thus with KO maternal grandmother like also for PIX). We studied their circadian locomotor activity and behavior in the elevated-plus-maze (EPM). Locomotor hyper-activity occurs in F1, the opposite occurs in F2, with MYX rats appearing undistinguishable from WT ones. Open-arm preference emerged in PIX and MIX. Only MAT and MYX showed a significant vulnerability for ADHD-like inattentive symptoms (duration of rearing in the EPM; Viggiano et al., 2002). A risk-taking profile is evident in the F2 phenotype while inattentiveness from F1 progeny tends to be transferred to F3. We hypothesize that DAT-related phenotypes result from effective inheritance through pedigree and are dependent on grandparents, suggesting a protective role for gestation of a future PAT dam in hyperdopaminergic uterus. For major features, similar odd (F1, F3) generations appear opposed to even (F2) ones; for minor specific features, the phenotype transfer may affect the progenies with a male but not a female DAT-KO ancestor
The Signalled Licking/Avoidance of Punishment (SLAP) Paradigm in Rats: Capacity for Insight Between Goal Conditioning and Signalling Contingencies
No full textIn developmental-age
kids with specific-learning-
disabilities
(SLD), functional illiteracy entails poor logical reasoning; in those
with attention-deficit/
hyperactivity disorder (ADHD), a deficit in prospective memory results in difficulty executing previously
planned actions. We model this SLD and/or ADHD construct in the rat via the signalled-licking/
avoidance-of-
punishment
protocol
(SLAP): We aim to study to assess rats' ability to merge two independently learned notions (one Pavlovian and one instrumental)
and their deliberate exploitation. Rats were tested in Skinner boxes with a water-dispenser
and lickometer. The ‘Flash’
paradigm consists of 30-min
daily sessions, in which 5-min
safe phases (i.e., sound and light off, signalled free-drinking)
are
intertwined by 1-min
unsafe phases (i.e., sound and light on). If subjects drink during unsafe phases, a mild footshock is released:
Rats learn to withhold drinking. The ‘Allow’ paradigm starts and stays in the unsafe phase. Rats can shift to a 2-min
safe
phase through a single nose poke in the active-hole.
The possibility to exert control over the environment, via seeking dark-and-
silence
(the predictive contingencies) as deliberate goal, is an unexplored construct in rats. In data from the ‘Flash’ paradigm, a
greater number of licks/h during safe phases is confirming that rats easily understand classical passive-avoidance
contingencies.
Findings from the ‘Allow’ paradigm indicate increased inefficacious nose pokes/h during safe phases, compared to unsafe ones.
This is clearly suggesting that rats associate the change of phase with an outcome of their own input into the active nose-poking
device. However, rats do not understand the ‘potential’ for instrumental exploitation of their nose pokes. As such, no significant
inferences were drawn across the two independent associative notions. Neurobiology of this putative ‘insight’ capability may rely
on limbic-striatal-
cortical
networks. Impairments in the latter may be involved in deficits of prospective memory (in ADHD),
and/or impairments in logic skills (in SLD). The SLAP protocol may offer insights on basic neurobiology as well as modulatory
effects thereon of pharmacological molecules
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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