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Size Matters: How Scaling Affects the Interaction between Grid and Border Cells.

ABSTRACT: Many hippocampal cell types are characterized by a progressive increase in scale along the dorsal-to-ventral axis, such as in the cases of head-direction, grid and place cells. Also located in the medial entorhinal cortex (MEC), border cells would be expected to benefit from such scale modulations. However, this phenomenon has not been experimentally observed. Grid cells in the MEC of mammals integrate velocity related signals to map the environment with characteristic hexagonal tessellation patterns. Due to the noisy nature of these input signals, path integration processes tend to accumulate errors as animals explore the environment, leading to a loss of grid-like activity. It has been suggested that border-to-grid cells' associations minimize the accumulated grid cells' error when rodents explore enclosures. Thus, the border-grid interaction for error minimization is a suitable scenario to study the effects of border cell scaling within the context of spatial representation. In this study, we computationally address the question of (i) border cells' scale from the perspective of their role in maintaining the regularity of grid cells' firing fields, as well as (ii) what are the underlying mechanisms of grid-border associations relative to the scales of both grid and border cells. Our results suggest that for optimal contribution to grid cells' error minimization, border cells should express smaller firing fields relative to those of the associated grid cells, which is consistent with the hypothesis of border cells functioning as spatial anchoring signals.

SUBMITTER: Santos-Pata D

PROVIDER: S-EPMC5513924 | biostudies-other | 2017

REPOSITORIES: biostudies-other

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Size Matters: Ryanodine Receptor Cluster Size Affects Arrhythmogenic Sarcoplasmic Reticulum Calcium Release.

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Shape Matters: Plant Architecture Affects Chemical Uniformity in Large-Size Medical Cannabis Plants.

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Size matters! Association between journal size and longitudinal variability of the Journal Impact Factor.

Project description:Analyses of the Journal Impact Factor (JIF) have grown to be a major topic in scientometric literature. Despite widespread and justified critique concerning the JIF and its application, the size of a journal as a predictor for its longitudinal variability-or stability-on a long-term level has not yet comprehensively been analyzed. This study aims to provide robust evidence for an association between JIF variability and the size of journals, expressed by the number of published articles (citable items). For this purpose, the complete set of journals included in the Incite Journal Citation Reports (JCR) with an JIF in the 2017 JCR edition (n = 8750) were analyzed for the association between journal size and longitudinal JIF dynamics. Our results, based on n = 4792 journals with a complete JIF data set over the timespan of 12 annual JIF changes show that larger journals publishing more citable items experience smaller annual changes of the JIF than smaller journals, yet with this association being reversed for journals with a very large number of total cites. Consequently and in accordance with the genuine intention of the JIF to serve as a basis for decisions on journal subscriptions, evaluation of current changes of the JIF have to be accompanied by consideration of the journal's size in order to be accurate and sensible.

| S-EPMC6874322 | biostudies-literature

Scaling of gene expression with liver cell size in vivo

Project description:A partially hepatectomized mouse liver with a liver-specific conditional Cdk1 knock-out genotype grows back to the normal size in the absence of cell divisions resulting in highly enlarged nuclear and cell size. This experiment analyses gene expression in four sets of mouse livers all with different nuclear sizes: controls without hepatectomy, controls with hepatectomy, Cdk1 null without hepatectomy and Cdk1 null with hepatectomy.

2014-03-06 | E-MTAB-1297 | biostudies-arrayexpress

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