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https://www.readbyqxmd.com/read/29691990/altered-functional-connectivity-strength-and-its-correlations-with-cognitive-function-in-subjects-with-ultra-high-risk-for-psychosis-at-rest
#1
Ran-Ran Li, Hai-Long Lyu, Feng Liu, Nan Lian, Ren-Rong Wu, Jing-Ping Zhao, Wen-Bin Guo
AIMS: Evidence of altered structural and functional connectivity in the frontal-occipital network is associated with cognitive deficits in patients with schizophrenia. However, the altered patterns of functional connectivity strength (FCS) in individuals with ultra-high risk (UHR) for psychosis remain unknown. In this study, whole-brain FCS was assessed to examine the altered patterns of FCS in UHR subjects. METHODS: A total of 34 UHR subjects and 37 age- and sex-matched healthy controls were enrolled to undergo resting-state functional magnetic resonance imaging...
April 24, 2018: CNS Neuroscience & Therapeutics
https://www.readbyqxmd.com/read/29688014/machine-learning-energy-gaps-of-porphyrins-with-molecular-graph-representations
#2
Zheng Li, Noushin Omidvar, Wei Shan Chin, Esther Robb, Amanda J Morris, Luke E K Achenie, Hongliang Xin
Molecular functionalization of porphyrins opens countless new opportunities in tailoring their physicochemical properties for light-harvesting applications. However, the immense materials space spanned by a vast number of substituent ligands and chelating metal ions prohibits high-throughput screening of combinatorial libraries. In this work, machine learning algorithms equipped with the domain knowledge of chemical graph theory were employed for predicting the energy gaps of >12000 porphyrins from the Computational Materials Repository...
April 24, 2018: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29687404/structural-connectome-differences-in-hiv-infection-brain-network-segregation-associated-with-nadir-cd4-cell-count
#3
Ryan P Bell, Laura L Barnes, Sheri L Towe, Nan-Kuei Chen, Allen W Song, Christina S Meade
This study investigated structural brain organization using diffusion tensor imaging (DTI) in 35 HIV-positive and 35 HIV-negative individuals. We used global and nodal graph theory metrics to investigate whether HIV was associated with differences in brain network organization based on fractional anisotropy (FA) and mean diffusivity (MD). Participants also completed a comprehensive neuropsychological testing battery. For global network metrics, HIV-positive individuals displayed a lower FA clustering coefficient relative to HIV-negative individuals...
April 23, 2018: Journal of Neurovirology
https://www.readbyqxmd.com/read/29685540/resting-state-functional-connectivity-mri-analysis-in-human-immunodeficiency-virus-and-hepatitis-c-virus-co-infected-subjects-a-pilot-study
#4
Simone Corgiolu, Luigi Barberini, Jasjit S Suri, Antonella Mandas, Diego Costaggiu, Paola Piano, Fulvio Zaccagna, Pierleone Lucatelli, Antonella Balestrieri, Luca Saba
BACKGROUND AND PURPOSE: Hepatitis C virus (HCV) co-infection's role on cognitive impairment of human immunodeficiency virus (HIV) positive patients is still debated and functional neuroimaging evaluation on this matter is lacking. To provide further insight about HCV's neuro-effects on HIV associated neurocognitive disorder (HAND), we performed a pilot resting state (RS) functional connectivity magnetic resonance imaging (fcMRI) study to find eventual functional connectivity alteration that could reflect HCV related cognitive performance degradation...
May 2018: European Journal of Radiology
https://www.readbyqxmd.com/read/29681803/anger-modulates-influence-hierarchies-within-and-between-emotional-reactivity-and-regulation-networks
#5
Yael Jacob, Gadi Gilam, Tamar Lin, Gal Raz, Talma Hendler
Emotion regulation is hypothesized to be mediated by the interactions between emotional reactivity and regulation networks during the dynamic unfolding of the emotional episode. Yet, it remains unclear how to delineate the effective relationships between these networks. In this study, we examined the aforementioned networks' information flow hierarchy during viewing of an anger provoking movie excerpt. Anger regulation is particularly essential for averting individuals from aggression and violence, thus improving prosocial behavior...
2018: Frontiers in Behavioral Neuroscience
https://www.readbyqxmd.com/read/29680789/neurophysiological-differences-in-the-adolescent-brain-following-a-single-night-of-restricted-sleep-a-7t-fmri-study
#6
Jennifer L Robinson, Stephen A Erath, Rajesh K Kana, Mona El-Sheikh
Sleep deprivation in youth has garnered international attention in recent years, as correlational studies have demonstrated significant relationships between lack of sleep and detrimental behavioral and academic outcomes. However, no study to date has systematically examined the neurophysiological consequences of a single night of sleep restriction (i.e., 4 h) in adolescents using ultra-high field functional neuroimaging. Much of what we know regarding the neural consequences of sleep deprivation has come from the adult literature, and among those studies, the majority use region of interest (ROI) approaches, thus disregarding the dynamic mechanisms that may subserve the behavioral effects of sleep restriction...
April 7, 2018: Developmental Cognitive Neuroscience
https://www.readbyqxmd.com/read/29680421/mapping-the-changed-hubs-and-corresponding-functional-connectivity-in-idiopathic-restless-legs-syndrome
#7
Chunyan Liu, Jiaojian Wang, Yue Hou, Zhigang Qi, Li Wang, Shuqin Zhan, Rong Wang, Yuping Wang
OBJECTIVE: The hubs of the brain network play a key role in integrating and transferring information between different functional modules. However, whether the changed pattern in functional network hubs contributes to the onset of leg discomfort symptoms in restless legs syndrome (RLS) patients remains unclear. Using resting-state functional magnetic resonance imaging (rs-fMRI) and graph theory methods, we investigated whether alterations of hubs can be detected in RLS. METHODS: First, we constructed the whole-brain voxelwise functional connectivity and calculated a functional connectivity strength (FCS) map in each of 16 drug-naive idiopathic RLS patients and 26 gender- and age-matched healthy control (HC) subjects...
May 2018: Sleep Medicine
https://www.readbyqxmd.com/read/29678937/identification-of-a-specific-functional-network-altered-in-poststroke-cognitive-impairment
#8
Clément Bournonville, Hilde Hénon, Thibaut Dondaine, Christine Delmaire, Stephanie Bombois, Anne-Marie Mendyk, Charlotte Cordonnier, Solène Moulin, Xavier Leclerc, Régis Bordet, Renaud Lopes
OBJECTIVE: To study the association between poststroke cognitive impairment and defining a specific resting functional marker. METHODS: The resting-state functional connectivity 6 months after an ischemic stroke in 56 patients was investigated. Twenty-nine of the patients who had an impairment of one or several cognitive domains were compared to 27 without any cognitive deficit. We studied the whole-brain connectivity using 2 complementary approaches: graph theory to study the functional network organization and network-based statistics to explore connectivity between brain regions...
April 20, 2018: Neurology
https://www.readbyqxmd.com/read/29676508/applications-of-social-network-analysis-to-obesity-a-systematic-review
#9
REVIEW
S Zhang, K de la Haye, M Ji, R An
People's health behaviours and outcomes can be profoundly shaped by the social networks they are embedded in. Based on graph theory, social network analysis is a research framework for the study of social interactions and the structure of these interactions among social actors. A literature search was conducted in PubMed and Web of Science for articles published until August 2017 that applied social network analysis to examine obesity and social networks. Eight studies (three cross-sectional and five longitudinal) conducted in the US (n = 6) and Australia (n = 2) were identified...
April 20, 2018: Obesity Reviews: An Official Journal of the International Association for the Study of Obesity
https://www.readbyqxmd.com/read/29675146/efficient-prediction-of-reaction-paths-through-molecular-graph-and-reaction-network-analysis
#10
Yeonjoon Kim, Jin Woo Kim, Zeehyo Kim, Woo Youn Kim
Despite remarkable advances in computational chemistry, prediction of reaction mechanisms is still challenging, because investigating all possible reaction pathways is computationally prohibitive due to the high complexity of chemical space. A feasible strategy for efficient prediction is to utilize chemical heuristics. Here, we propose a novel approach to rapidly search reaction paths in a fully automated fashion by combining chemical theory and heuristics. A key idea of our method is to extract a minimal reaction network composed of only favorable reaction pathways from the complex chemical space through molecular graph and reaction network analysis...
January 28, 2018: Chemical Science
https://www.readbyqxmd.com/read/29670045/what-we-know-about-the-brain-structure-function-relationship
#11
REVIEW
Karla Batista-García-Ramó, Caridad Ivette Fernández-Verdecia
How the human brain works is still a question, as is its implication with brain architecture: the non-trivial structure–function relationship. The main hypothesis is that the anatomic architecture conditions, but does not determine, the neural network dynamic. The functional connectivity cannot be explained only considering the anatomical substrate. This involves complex and controversial aspects of the neuroscience field and that the methods and methodologies to obtain structural and functional connectivity are not always rigorously applied...
April 18, 2018: Behavioral Sciences
https://www.readbyqxmd.com/read/29668743/graph-theory-applied-to-the-analysis-of-motor-activity-in-patients-with-schizophrenia-and-depression
#12
Erlend Eindride Fasmer, Ole Bernt Fasmer, Jan Øystein Berle, Ketil J Oedegaard, Erik R Hauge
Depression and schizophrenia are defined only by their clinical features, and diagnostic separation between them can be difficult. Disturbances in motor activity pattern are central features of both types of disorders. We introduce a new method to analyze time series, called the similarity graph algorithm. Time series of motor activity, obtained from actigraph registrations over 12 days in depressed and schizophrenic patients, were mapped into a graph and we then applied techniques from graph theory to characterize these time series, primarily looking for changes in complexity...
2018: PloS One
https://www.readbyqxmd.com/read/29668696/the-minimal-abc-trees-with-b1-branches
#13
Darko Dimitrov, Zhibin Du, Carlos M da Fonseca
The atom-bond connectivity index (or, for short, ABC index) is a molecular structure descriptor bridging chemistry to graph theory. It is probably the most studied topological index among all numerical parameters of a graph that characterize its topology. For a given graph G = (V, E), the ABC index of G is defined as [Formula: see text], where di denotes the degree of the vertex i, and ij is the edge incident to the vertices i and j. A combination of physicochemical and the ABC index properties are commonly used to foresee the bioactivity of different chemical composites...
2018: PloS One
https://www.readbyqxmd.com/read/29667682/modeling-the-free-radical-polymerization-of-hexanediol-diacrylate-hdda-a-molecular-dynamics-and-graph-theory-approach
#14
Ariana Torres-Knoop, Ivan Kryven, Verena Schamboeck, Piet D Iedema
In the printing, coating and ink industries, photocurable systems are becoming increasingly popular and multi-functional acrylates are one of the most commonly used monomers due to their high reactivity (fast curing). In this paper, we use molecular dynamics and graph theory tools to investigate the thermo-mechanical properties and topology of hexanediol diacrylate (HDDA) polymer networks. The gel point was determined as the point where a giant component was formed. For the conditions of our simulations, we found the gel point to be around 0...
April 18, 2018: Soft Matter
https://www.readbyqxmd.com/read/29664012/current-phase-relation-from-graphs-and-diagrams-and-application-to-thick-ferromagnetic-josephson-junctions
#15
I Margaris, V Paltoglou, N Flytzanis
In this work we present a method of representing terms in the current-phase-relation of a ballistic Josephson junction by combinations of diagrams, used in previous work to represent an equivalent of the matching condition determinant of the junction. This is accomplished by the expansion of the logarithm of this determinant in Taylor series and keeping track of surviving terms, i.e. terms that do not annihilate each other. The types of the surviving terms are represented by connected graphs, whose points represent diagrammatic terms of the determinant expansion...
April 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/29662443/emotion-regulation-and-complex-brain-networks-association-between-expressive-suppression-and-efficiency-in-the-fronto-parietal-network-and-default-mode-network
#16
Junhao Pan, Liying Zhan, ChuanLin Hu, Junkai Yang, Cong Wang, Li Gu, Shengqi Zhong, Yingyu Huang, Qian Wu, Xiaolin Xie, Qijin Chen, Hui Zhou, Miner Huang, Xiang Wu
Emotion regulation (ER) refers to the "implementation of a conscious or non-conscious goal to start, stop or otherwise modulate the trajectory of an emotion" (Etkin et al., 2015). Whereas multiple brain areas have been found to be involved in ER, relatively little is known about whether and how ER is associated with the global functioning of brain networks. Recent advances in brain connectivity research using graph-theory based analysis have shown that the brain can be organized into complex networks composed of functionally or structurally connected brain areas...
2018: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/29651014/altered-connection-properties-of-important-network-hubs-may-be-neural-risk-factors-for-individuals-with-primary-insomnia
#17
Xuming Liu, Jiyong Zheng, Bi-Xia Liu, Xi-Jian Dai
Primary insomnia (PIs) is highly prevalent and can lead to adverse socioeconomic impacts, but the underlying mechanism of its complex brain network impairment remains largely unknown. Functional studies are too few and diverse in methodology, which makes it difficult to glean general conclusions. To answer this question, we first used graph theory-based network analyse, together with seed-based functional connectivity approach, to characterize the topology architecture of whole-brain functional networks associated with PIs...
April 12, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29648927/one-teacher-s-experience-of-teaching-physical-education-and-another-school-subject-an-inter-role-conflict
#18
Cassandra Iannucci, Ann MacPhail
PURPOSE: This study was situated within a longitudinal study of 5 teachers examining the realities of teaching physical education by determining the impact of individual dispositions and contextual factors on the career trajectories of postprimary physical education teachers in Ireland (Iannucci & MacPhail, 2017). One of these participants, Jane, was examined in this study to gain a greater understanding of the realities and tensions experienced by a postprimary teacher enacting 2 distinct sets of role expectations when teaching physical education and another school subject concurrently...
April 12, 2018: Research Quarterly for Exercise and Sport
https://www.readbyqxmd.com/read/29628529/ssc-eke-semi-supervised-classification-with-extensive-knowledge-exploitation
#19
Pengjiang Qian, Chen Xi, Min Xu, Yizhang Jiang, Kuan-Hao Su, Shitong Wang, Raymond F Muzic
We introduce a new, semi-supervised classification method that extensively exploits knowledge. The method has three steps. First, the manifold regularization mechanism, adapted from the Laplacian support vector machine (LapSVM), is adopted to mine the manifold structure embedded in all training data, especially in numerous label-unknown data. Meanwhile, by converting the labels into pairwise constraints, the pairwise constraint regularization formula (PCRF) is designed to compensate for the few but valuable labelled data...
January 2018: Information Sciences
https://www.readbyqxmd.com/read/29624619/time-estimation-and-beta-segregation-an-eeg-study-and-graph-theoretical-approach
#20
Amir Hossein Ghaderi, Shadi Moradkhani, Arvin Haghighatfard, Fatemeh Akrami, Zahra Khayyer, Fuat Balcı
Elucidation of the neural correlates of time perception constitutes an important research topic in cognitive neuroscience. The focus to date has been on durations in the millisecond to seconds range, but here we used electroencephalography (EEG) to examine brain functional connectivity during much longer durations (i.e., 15 min). For this purpose, we conducted an initial exploratory experiment followed by a confirmatory experiment. Our results showed that those participants who overestimated time exhibited lower activity of beta (18-30 Hz) at several electrode sites...
2018: PloS One
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