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https://www.readbyqxmd.com/read/29155809/multivariate-pattern-dependence
#1
Stefano Anzellotti, Alfonso Caramazza, Rebecca Saxe
When we perform a cognitive task, multiple brain regions are engaged. Understanding how these regions interact is a fundamental step to uncover the neural bases of behavior. Most research on the interactions between brain regions has focused on the univariate responses in the regions. However, fine grained patterns of response encode important information, as shown by multivariate pattern analysis. In the present article, we introduce and apply multivariate pattern dependence (MVPD): a technique to study the statistical dependence between brain regions in humans in terms of the multivariate relations between their patterns of responses...
November 20, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/29155080/a-comprehensive-analysis-of-resting-state-fmri-measures-to-classify-individual-patients-with-alzheimer-s-disease
#2
Frank de Vos, Marisa Koini, Tijn M Schouten, Stephan Seiler, Jeroen van der Grond, Anita Lechner, Reinhold Schmidt, Mark de Rooij, Serge A R B Rombouts
Alzheimer's disease (AD) patients show altered patterns of functional connectivity (FC) on resting state functional magnetic resonance imaging (RSfMRI) scans. It is yet unclear which RSfMRI measures are most informative for the individual classification of AD patients. We investigated this using RSfMRI scans from 77 AD patients (MMSE = 20.4 ± 4.5) and 173 controls (MMSE = 27.5 ± 1.8). We calculated i) FC matrices between resting state components as obtained with independent component analysis (ICA), ii) the dynamics of these FC matrices using a sliding window approach, iii) the graph properties (e...
November 14, 2017: NeuroImage
https://www.readbyqxmd.com/read/29155009/thresholds-for-sine-wave-corrugations-defined-by-binocular-disparity-in-random-dot-stereograms-factor-analysis-of-individual-differences-revealstwo-stereoscopic-mechanisms-tuned-for-spatial-frequency
#3
David H Peterzell, Ignacio Serrano-Pedraza, Michael Widdall, Jenny C A Read
Threshold functions for sinusoidal depth corrugations typically reach their minimum (highest sensitivity) at spatial frequencies of 0.2-0.4 cycles/degree (cpd), with lower thresholds for horizontal than vertical corrugations at low spatial frequencies. To elucidate spatial frequency and orientation tuning of stereoscopic mechanisms, we measured the disparity sensitivity functions, and used factor analytic techniques to estimate the existence of independent underlying stereo channels. The data set (N=30 individuals) was for horizontal and vertical corrugations of spatial frequencies ranging from 0...
November 15, 2017: Vision Research
https://www.readbyqxmd.com/read/29154365/is-neural-processing-of-negative-stimuli-altered-in-addiction-independent-of-drug-effects-findings-from-drug-na%C3%A3-ve-youth-with-internet-gaming-disorder
#4
Sarah W Yip, James J Gross, Megha Chawla, Shan-Shan Ma, Xing-Hui Shi, Lu Liu, Yuan-Wei Yao, Lei Zhu, Patrick D Worhunsky, Jintao Zhang
Difficulties in emotion regulation are commonly reported among individuals with alcohol and drug addictions and contribute to the acquisition and maintenance of addictive behaviors. Alterations in neural processing of negative affective stimuli have further been demonstrated among individuals with addictions. However, it is unclear whether these alterations are a general feature of addictions or are a result of prolonged exposure to drugs-of-abuse. To test the hypothesis of altered negative affect processing independent of drug effects, this study assessed neural function among drug-naïve youth with a behavioral addiction-Internet gaming disorder (IGD)...
November 20, 2017: Neuropsychopharmacology: Official Publication of the American College of Neuropsychopharmacology
https://www.readbyqxmd.com/read/29154054/the-effects-of-chamomile-extract-on-sleep-quality-among-elderly-people-a-clinical-trial
#5
Mohsen Adib-Hajbaghery, Seyedeh Nesa Mousavi
BACKGROUND: The prevalence of insomnia increases with age. Chamomile is among the medicinal plants which are used as tranquilizer. Yet, there is inadequate experimental and clinical evidence regarding its hypnotic effects. This study sought to evaluate the effects of chamomile extract on sleep quality among elderly people. DESIGN: A single-blind randomized controlled trial was performed. SETTING: A convenient sample of sixty elderly people who aged sixty or more and lived in Kahrizak day care nursing home, Karaj, Iran, were randomly allocated to a control and a treatment group...
December 2017: Complementary Therapies in Medicine
https://www.readbyqxmd.com/read/29152692/left-frontoparietal-network-activity-is-modulated-by-drug-stimuli-in-cocaine-addiction
#6
Víctor Costumero, Patricia Rosell-Negre, Juan Carlos Bustamante, Paola Fuentes-Claramonte, Juan José Llopis, Cesar Ávila, Alfonso Barrós-Loscertales
Cocaine addicts present reduced activity in the left frontoparietal network, a brain network associated with cognitive control, during the processing of non-drug reward related stimuli (Costumero et al., Addiction Biology 22:479-489, 2015). However, the involvement of this network in drug-related stimuli processing remains unclear. Here, fifteen cocaine-dependent men and fifteen healthy matched controls viewed cocaine-related, erotic, aversive, and neutral pictures during an fMRI session. Group independent component analysis was then performed to investigate how functional networks were modulated by the different emotional images...
November 20, 2017: Brain Imaging and Behavior
https://www.readbyqxmd.com/read/29151960/r-e-n-a-l-nephrometry-score-a-preoperative-risk-factor-predicting-the-fuhrman-grade-of-clear-cell-renal-carcinoma
#7
Shao-Hao Chen, Yu-Peng Wu, Xiao-Dong Li, Tian Lin, Qing-Yong Guo, Ye-Hui Chen, Jin-Bei Huang, Yong Wei, Xue-Yi Xue, Qing-Shui Zheng, Ning Xu
Objective: The purpose of this study was to evaluate the efficacy and feasibility of the R.E.N.A.L. Nephrometry Score to postoperatively predict high-grade clear-cell renal carcinoma (ccRCC). Methods: The study included 288 patients diagnosed with ccRCC who had complete CT/CTA data and R.E.N.A.L. Nephrometry Scores and underwent renal surgery at our center between January 2012 and December 2015. The relationship between the pathological grade of renal masses and R.E.N.A.L. Nephrometry Score was evaluated. Results: Univariate analysis indicated that diagnostic modality, cystic necrosis, enlargement of the regional lymph node, distant metastasis, clinical T stage, TNM stage, surgical modality, tumor size, nearness of the tumor to the collecting system or sinus, total Nephrometry Score and individual anatomic descriptor components were significantly associated with postoperative tumor grade (P < 0...
2017: Journal of Cancer
https://www.readbyqxmd.com/read/29148252/sex-hormone-binding-globulin-shbg-is-a-potential-early-diagnostic-biomarker-for-gastric-cancer
#8
Chao-Wen Cheng, Che-Chang Chang, Yudha Nur Patria, Ruei-Ting Chang, Yun-Ru Liu, Fu-An Li, Hsiu-Ming Shih, Ching-Yu Lin
The use of blood plasma biomarkers in gastric cancer (GC) management is limited due to a lack of reliable biomarkers. An LC-MS/MS assay and a bioinformatic analysis were performed to identify blood plasma biomarkers in a GC discovery cohort. The data obtained were verified and validated by western blotting and an ELISA in an independent study cohort. A label-free quantification analysis of the MS data using PEAKS7 software found that four plasma proteins of apolipoprotein C-1, gelsolin, sex hormone-binding globulin (SHBG), and complement component C4-A were significantly overexpressed in GC patients...
November 17, 2017: Cancer Medicine
https://www.readbyqxmd.com/read/29148155/identifying-biomechanical-gait-parameters-in-adolescent-boys-with-haemophilia-using-principal-component-analysis
#9
L B Suckling, D Stephensen, M C Cramp, R Mahaffey, W I Drechsler
INTRODUCTION: Improvements in the medical management for those with haemophilia have resulted in improved clinical outcomes. However, current treatment regimens do not alleviate all joint haemarthroses with the potential for long-term joint deterioration remaining. The evaluation of functional activities such as gait, using standardized tools to monitor children with haemophilia is emerging. AIM: This study explored differences in sagittal plane biomechanics of walking in adolescent boys aged 11-18 years with haemophilia and an age-matched group of typically developing boys...
November 17, 2017: Haemophilia: the Official Journal of the World Federation of Hemophilia
https://www.readbyqxmd.com/read/29146340/effect-of-the-composition-of-extra-virgin-olive-oils-on-the-differentiation-and-antioxidant-capacities-of-twelve-monovarietals
#10
Edwar Fuentes, Fiorela Paucar, Francisco Tapia, Jaime Ortiz, Paula Jimenez, Nalda Romero
The effect of the composition of twelve varieties of extra virgin olive oils (EVOOs) on their differentiation based in agronomic criteria and on the antioxidant capacity was studied. Principal component analysis permitted an overview of the samples and their compositions, showing evidence of grouping and correlation between antioxidant capacity, oleuropein and ligstroside derivatives (OLD) and specific extinction at 270. Oleic and linoleic acids, 3,4-DHPEA-EA and p-HPEA-EDA (OLD), unsaturated/saturated ratio and induction time (IT) allowed the correct classification of samples according to year of harvest, ripening stage and variety...
March 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29146299/functional-connectivity-during-affective-mentalizing-in-criminal-offenders-with-psychotic-disorders-associations-with-clinical-symptoms
#11
Carla L Harenski, Vince D Calhoun, Juan R Bustillo, Brian W Haas, Jean Decety, Keith A Harenski, Michael F Caldwell, Gregory J Van Rybroek, Michael Koenigs, David M Thornton, Kent A Kiehl
Psychotic disorders are associated with neurobehavioral impairments in mental state attribution (mentalizing). These impairments are most severe in psychotic patients with elevated symptom levels, particularly negative and cognitive symptoms. There have been few studies of functional connectivity related to mentalizing in psychotic disorders and associations with symptoms. We conducted a functional MRI study of affective mentalizing in individuals with psychotic disorders and varying symptom levels (positive, negative, cognitive)...
November 6, 2017: Psychiatry Research
https://www.readbyqxmd.com/read/29145761/non-fluent-speech-following-stroke-is-caused-by-impaired-efference-copy
#12
Lynda Feenaughty, Alexandra Basilakos, Leonardo Bonilha, Dirk-Bart den Ouden, Chris Rorden, Brielle Stark, Julius Fridriksson
Efference copy is a cognitive mechanism argued to be critical for initiating and monitoring speech: however, the extent to which breakdown of efference copy mechanisms impact speech production is unclear. This study examined the best mechanistic predictors of non-fluent speech among 88 stroke survivors. Objective speech fluency measures were subjected to a principal component analysis (PCA). The primary PCA factor was then entered into a multiple stepwise linear regression analysis as the dependent variable, with a set of independent mechanistic variables...
November 17, 2017: Cognitive Neuropsychology
https://www.readbyqxmd.com/read/29145644/paf1-and-ctr9-core-components-of-the-paf1-complex-maintain-low-levels-of-telomeric-repeat-containing-rna
#13
Joana Rodrigues, David Lydall
The conserved PAF1 complex (Cdc73, Paf1, Ctr9, Leo1 and Rtf1, in yeast), binds RNA pol II, and affects levels of many RNAs. Although PAF1 is a complex, there is evidence that different components perform different functions. In yeast, Cdc73, Paf1 and Ctr9 maintain normal telomerase RNA (TLC1) levels and affect telomere length. Here we report a new connection between the PAF1 complex and telomere biology. We show that Paf1 and Ctr9 maintain low telomere repeat containing RNA (TERRA) levels while Cdc73, Leo1 and Rtf1 have lesser effects...
November 14, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/29145496/insights-into-soybean-transcriptome-reconfiguration-under-hypoxic-stress-functional-regulatory-structural-and-compositional-characterization
#14
Thiago J Nakayama, Fabiana A Rodrigues, Norman Neumaier, Juliana Marcolino-Gomes, Hugo B C Molinari, Thaís R Santiago, Eduardo F Formighieri, Marcos F Basso, José R B Farias, Beatriz M Emygdio, Ana C B de Oliveira, Ângela D Campos, Aluízio Borém, Frank G Harmon, Liliane M Mertz-Henning, Alexandre L Nepomuceno
Soybean (Glycine max) is one of the major crops worldwide and flooding stress affects the production and expansion of cultivated areas. Oxygen is essential for mitochondrial aerobic respiration to supply the energy demand of plant cells. Because oxygen diffusion in water is 10,000 times lower than in air, partial (hypoxic) or total (anoxic) oxygen deficiency is important component of flooding. Even when oxygen is externally available, oxygen deficiency frequently occurs in bulky, dense or metabolically active tissues such as phloem, meristems, seeds, and fruits...
2017: PloS One
https://www.readbyqxmd.com/read/29144851/the-prejudice-against-asylum-seekers-scale-presenting-the-psychometric-properties-of-a-new-measure-of-classical-and-conditional-attitudes
#15
Joel R Anderson
This paper reports the initial psychometric properties for the recently developed prejudice against asylum seekers scale (PAAS) - a new measure of the classical and conditional components of negative attitudes towards asylum seekers. Across three studies the initial psychometric evidence is presented: An exploratory factor analysis suggested that the 16 items of the PAAS accurately factor onto the two hypothesized subscales (Study 1), which was ratified using a confirmatory factor analysis (Study 2). The presented reliability estimates (internal consistency: Studies 1-3; test-retest reliability: Study 3) verified the stability of the measure...
November 16, 2017: Journal of Social Psychology
https://www.readbyqxmd.com/read/29143877/ft-mir-and-nir-spectral-data-fusion-a-synergetic-strategy-for-the-geographical-traceability-of-panax-notoginseng
#16
Yun Li, Jin-Yu Zhang, Yuan-Zhong Wang
Three data fusion strategies (low-llevel, mid-llevel, and high-llevel) combined with a multivariate classification algorithm (random forest, RF) were applied to authenticate the geographical origins of Panax notoginseng collected from five regions of Yunnan province in China. In low-level fusion, the original data from two spectra (Fourier transform mid-IR spectrum and near-IR spectrum) were directly concatenated into a new matrix, which then was applied for the classification. Mid-level fusion was the strategy that inputted variables extracted from the spectral data into an RF classification model...
November 16, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29142974/profiling-of-plasma-metabolites-suggests-altered-mitochondrial-fuel-usage-and-remodeling-of-sphingolipid-metabolism-in-individuals-with-type%C3%A2-2-diabetes-and-kidney-disease
#17
Jian-Jun Liu, Sujoy Ghosh, Jean-Paul Kovalik, Jianhong Ching, Hyung Won Choi, Subramaniam Tavintharan, Choon Nam Ong, Chee Fang Sum, Scott A Summers, E Shyong Tai, Su Chi Lim
Introduction: Pathophysiology of diabetic kidney disease (DKD) is incompletely understood. We aim to elucidate metabolic abnormalities associated with DKD in type 2 diabetes mellitus (T2DM) by targeted plasma metabolomics. Methods: A total of 126 T2DM participants with early DKD (urinary albumin-to-creatinine ratio [ACR] 30-299 mg/g and eGFR ≥ 60 ml/min/1.73 m(2)), 154 overt DKD (ACR ≥ 300 mg/g or eGFR < 60 ml/min/1.73 m(2)), and 129 non-DKD T2DM controls (ACR < 30 mg/g and eGFR ≥ 60 ml/min/1...
May 2017: KI Reports
https://www.readbyqxmd.com/read/29140267/detection-of-partial-discharge-sources-using-uhf-sensors-and-blind-signal-separation
#18
Carlos Boya, Guillermo Robles, Emilio Parrado-Hernández, Marta Ruiz-Llata
The measurement of the emitted electromagnetic energy in the UHF region of the spectrum allows the detection of partial discharges and, thus, the on-line monitoring of the condition of the insulation of electrical equipment. Unfortunately, determining the affected asset is difficult when there are several simultaneous insulation defects. This paper proposes the use of an independent component analysis (ICA) algorithm to separate the signals coming from different partial discharge (PD) sources. The performance of the algorithm has been tested using UHF signals generated by test objects...
November 15, 2017: Sensors
https://www.readbyqxmd.com/read/29136906/comparison-of-common-components-analysis-with-principal-components-analysis-and-independent-components-analysis-application-to-spme-gc-ms-volatolomic-signatures
#19
Jihéne Bouhlel, Delphine Jouan-Rimbaud Bouveresse, Said Abouelkaram, Elisabeth Baéza, Catherine Jondreville, Angélique Travel, Jérémy Ratel, Erwan Engel, Douglas N Rutledge
The aim of this work is to compare a novel exploratory chemometrics method, Common Components Analysis (CCA), with Principal Components Analysis (PCA) and Independent Components Analysis (ICA). CCA consists in adapting the multi-block statistical method known as Common Components and Specific Weights Analysis (CCSWA or ComDim) by applying it to a single data matrix, with one variable per block. As an application, the three methods were applied to SPME-GC-MS volatolomic signatures of livers in an attempt to reveal volatile organic compounds (VOCs) markers of chicken exposure to different types of micropollutants...
February 1, 2018: Talanta
https://www.readbyqxmd.com/read/29136883/programmable-fow-injection-principle-methodology-and-application-for-trace-analysis-of-iron-in-a-sea-water-matrix
#20
Mariko Hatta, Christopher I Measures, Jaromir Jarda Ruzicka
Automation of reagent based assays by Flow Injection is based on sample processing, in which a sample flows continuously towards and through a detector for monitoring of its components. There are three drawbacks to using this approach. The constant continuous forward flow: continually consumes reagents and generates chemical waste and necessitates a compromise when optimizing the performance of the reagent based assay. The reason is that individual steps of an assay protocol, i.e., sample and reagent metering, mixing, incubation, monitoring and efficient washout are carried out most efficiently on different time scales and therefore at different flowrates...
February 1, 2018: Talanta
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