Search results for "Neural"

Prospective study of sport dropout: A motivational analysis as a function of age and gender

2012

Abstract Introduction: This paper aimed to analyse the predictive ability of a self-determination theory (SDT) based model describing competitive sport dropout, and variance as a function of age and gender. Variables included in the model were: psychological need satisfaction, self-determined motivation, perceived conflict between sport and study, intention to practise sport, and dropout. Methods: A prospective study was performed over a period of 19 months. Variables considered as predictors of sport dropout were measured initially, and after 19 months persistence or dropout was assessed. The sample consisted of 857 athletes aged 11–19 (mean value 15.3; standard deviation = 1.77), 680 male…

Correction: Widespread white matter microstructural abnormalities in bipolar disorder: evidence from mega- and meta-analyses across 3033 individuals

2019

Fronto-limbic white matter (WM) abnormalities are assumed to lie at the heart of the pathophysiology of bipolar disorder (BD); however, diffusion tensor imaging (DTI) studies have reported heterogeneous results and it is not clear how the clinical heterogeneity is related to the observed differences. This study aimed to identify WM abnormalities that differentiate patients with BD from healthy controls (HC) in the largest DTI dataset of patients with BD to date, collected via the ENIGMA network. We gathered individual tensor-derived regional metrics from 26 cohorts leading to a sample size of N = 3033 (1482 BD and 1551 HC). Mean fractional anisotropy (FA) from 43 regions of interest (ROI) a…

Drugs and Nondrugs:  An Effective Discrimination with Topological Methods and Artificial Neural Networks

2003

A set of topological and structural descriptors has been used to discriminate general pharmacological activity. To that end, we selected a group of molecules with proven pharmacological activity including different therapeutic categories, and another molecule group without any activity. As a method for pharmacological activity discrimination, an artificial neural network was used, dividing molecules into active and inactive, to train the network and externally validate it. The following plot frequency distribution diagrams were used: a function of the number of drugs within a value interval, and the output value of the neural network versus these values. Pharmacological distribution diagram…

Acupuncture: its neurophysiological basis: an anaesthetist's foreword.

1978

The rates of adult neurogenesis and oligodendrogenesis are linked to cell cycle regulation through p27-dependent gene repression of SOX2

2023

Abstract Cell differentiation involves profound changes in global gene expression that often have to occur in coordination with cell cycle exit. Because cyclin-dependent kinase inhibitor p27 reportedly regulates proliferation of neural progenitor cells in the subependymal neurogenic niche of the adult mouse brain, but can also have effects on gene expression, we decided to molecularly analyze its role in adult neurogenesis and oligodendrogenesis. At the cell level, we show that p27 restricts residual cyclin-dependent kinase activity after mitogen withdrawal to antagonize cycling, but it is not essential for cell cycle exit. By integrating genome-wide gene expression and chromatin accessibil…

The action of iontophoretically applied acetylcholine and dopamine on single claustrum neurones in the cat.

1981

Abstract The effects of iontophoretically applied acetyl-choline (ACh) and dopamine (DA) on spontaneously active claustral neurones, in chloralose-anaesthetised cats, have been investigated. Acetylcholine had both facilitatory and inhibitory effects in almost the same proportions. The action of DA was prevalently inhibitory. Two types of inhibitory response to ACh and DA are described: short-lasting inhibition and long-lasting inhibition. The excitatory response always outlasted the period of drug application.

Neurotransmitters involved in the habenular control of raphe-hippocampal circuit

1989

cGMP modulates stem cells differentiation to neurons in brain in vivo pathological implications

2011

During brain development there is a strict control of the proliferation, migration and differentiation of neural stem cells to different cell types. Alterations in the control of these processes may result in altered balance in the formation of different cell types resulting in a long-lasting impairment of cerebral processes. This occurs for example if brain is exposed to alcohol during key stages of development which results in accelerated glial cells formation, impaired neuron formation and impaired cognitive function. The molecular mechanisms modulating differentiation of neural stem cells to neurons or non neuronal cells are not well known. Nitric oxide (NO) plays a relevant role in thi…

The Prediction of Human Intestinal Absorption Based on the Molecular Structure

2014

Human Intestinal Absorption (HIA) has been modeled many times by using classification models. However, regression models are scarce. Here, Artificial Neural Networks (ANNs) are implemented for this purpose. A dataset of structurally diverse chemicals with their respective experimental HIA were used to design robust, true predictive and widespread applicable ANN models. An input variables pool was made up of structural invariants calculated by using either Dragon or our software Desmol 1. The selection of best variables was performed following three steps using the entire dataset of molecules. Firstly, variables poorly correlated with the experimental data were eliminated. Secondly, input va…

Critical and tricritical singularities of the three-dimensional random-bond Potts model for large $q$

2005

We study the effect of varying strength, $\delta$, of bond randomness on the phase transition of the three-dimensional Potts model for large $q$. The cooperative behavior of the system is determined by large correlated domains in which the spins points into the same direction. These domains have a finite extent in the disordered phase. In the ordered phase there is a percolating cluster of correlated spins. For a sufficiently large disorder $\delta>\delta_t$ this percolating cluster coexists with a percolating cluster of non-correlated spins. Such a co-existence is only possible in more than two dimensions. We argue and check numerically that $\delta_t$ is the tricritical disorder, which se…