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https://www.readbyqxmd.com/read/27935733/correction-to-kane-et-al-2016
#1
Michael J Kane, Matt E Meier, Bridget A Smeekens, Georgina M Gross, Charlotte A Chun, Paul J Silvia, Thomas R Kwapil
Reports an error in "Individual differences in the executive control of attention, memory, and thought, and their associations with schizotypy" by Michael J. Kane, Matt E. Meier, Bridget A. Smeekens, Georgina M. Gross, Charlotte A. Chun, Paul J. Silvia and Thomas R. Kwapil (Journal of Experimental Psychology: General, 2016[Aug], Vol 145[8], 1017-1048). There were errors in Table 3 and Table 7 (these transcription errors were limited to descriptive statistics in the Tables and did not affect any inferential statistics)...
December 2016: Journal of Experimental Psychology. General
https://www.readbyqxmd.com/read/27931179/structural-and-functional-integrity-of-the-intraparietal-sulcus-in-moderate-and-severe-traumatic-brain-injury
#2
Chandler Sours, Prashant Raghavan, Alexandre Medina de Jesus, Steven R Roys, Li Jiang, Jiachen Zhuo, Rao P Gullapalli
Severe and Moderate TBI (sTBI) often results in long-term cognitive deficits such as reduced processing speed and attention. The intraparietal sulcus (IPS) is a neocortical structure that plays a crucial role in the deeply interrelated processes of multisensory processing and top down attention. Therefore, we hypothesized that disruptions in the functional and structural connections of the IPS may play a role in the development of such deficits. To examine these connections we used resting state fMRI (rsfMRI) and diffusion kurtosis imaging (DKI) in a cohort of 27 sTBI patients (29...
December 8, 2016: Journal of Neurotrauma
https://www.readbyqxmd.com/read/27929929/diffusion-kurtosis-imaging-study-of-rectal-adenocarcinoma-associated-with-histopathologic-prognostic-factors-preliminary-findings
#3
Lan Zhu, Zilai Pan, Qian Ma, Wenjie Yang, Hongyuan Shi, Caixia Fu, Xu Yan, Lianjun Du, Fuhua Yan, Huan Zhang
Purpose To determine the correlation between diffusion kurtosis imaging (DKI)-derived parameters and prognostic factors for rectal adenocarcinoma. Materials and Methods This study was approved by the local institute review board, and written informed consent was obtained from each patient. Data from 56 patients (median age, 59.5 years; age range, 31-86 years) with rectal adenocarcinoma between April 2014 and September 2015 were involved in this prospective study. DKI (b = 0, 700, 1400, and 2100 sec/mm(2)) and conventional diffusion-weighted imaging (b = 0, 1000 sec/mm(2)) were performed...
December 5, 2016: Radiology
https://www.readbyqxmd.com/read/27923670/early-and-progressive-microstructural-brain-changes-in-mice-overexpressing-human-%C3%AE-synuclein-detected-by-diffusion-kurtosis-imaging
#4
Amit Khairnar, Jana Ruda-Kucerova, Nikoletta Szabó, Eva Drazanova, Anas Arab, Birgit Hutter-Paier, Joerg Neddens, Peter Latta, Zenon Starcuk, Irena Rektorova
Diffusion kurtosis imaging (DKI) is sensitive in detecting α-Synuclein (α-Syn) accumulation-associated microstructural changes at late stages of the pathology in α-Syn overexpressing TNWT-61 mice. The aim of this study was to perform DKI in young TNWT-61 mice when α-Syn starts to accumulate and to compare the imaging results with an analysis of motor and memory impairment and α-Syn levels. Three-month-old (3mo) and six-month-old (6mo) mice underwent DKI scanning using the Bruker Avance 9.4 Tesla magnetic resonance imaging system...
December 3, 2016: Brain, Behavior, and Immunity
https://www.readbyqxmd.com/read/27908136/polymer-extension-under-flow-some-statistical-properties-of-the-work-distribution-function
#5
Aishani Ghosal, Binny J Cherayil
In an extension of earlier studies from this group on the application of the Jarzynski equality to the determination of the elastic properties of a finitely extensible Rouse model of polymers under flow [A. Ghosal and B. J. Cherayil, J. Chem. Phys. 144, 214902 (2016)], we derive several new theoretical results in this paper on the nature of the distribution function P(w) that governs the long-time limit t>1 of the fluctuations in the work w performed by the polymer during flow-induced stretching. In particular, we show that an expression for the average of the nth power of the work, ⟨w(n)(t)⟩, can be obtained in closed form in this limit, making it possible to exactly calculate three important statistical measures of P(w): the mean μ, the skewness γ1, and the kurtosis γ2 (apart from the variance σ(2))...
November 28, 2016: Journal of Chemical Physics
https://www.readbyqxmd.com/read/27900458/utility-of-whole-lesion-adc-histogram-metrics-for-assessing-the-malignant-potential-of-pancreatic-intraductal-papillary-mucinous-neoplasms-ipmns
#6
David H Hoffman, Justin M Ream, Christina H Hajdu, Andrew B Rosenkrantz
PURPOSE: To evaluate whole-lesion ADC histogram metrics for assessing the malignant potential of pancreatic intraductal papillary mucinous neoplasms (IPMNs), including in comparison with conventional MRI features. METHODS: Eighteen branch-duct IPMNs underwent MRI with DWI prior to resection (n = 16) or FNA (n = 2). A blinded radiologist placed 3D volumes-of-interest on the entire IPMN on the ADC map, from which whole-lesion histogram metrics were generated. The reader also assessed IPMN size, mural nodularity, and adjacent main-duct dilation...
November 30, 2016: Abdominal Radiology
https://www.readbyqxmd.com/read/27893768/macromolecular-crowding-regulates-the-gene-expression-profile-by-limiting-diffusion
#7
Mahdi Golkaram, Stefan Hellander, Brian Drawert, Linda R Petzold
We seek to elucidate the role of macromolecular crowding in transcription and translation. It is well known that stochasticity in gene expression can lead to differential gene expression and heterogeneity in a cell population. Recent experimental observations by Tan et al. have improved our understanding of the functional role of macromolecular crowding. It can be inferred from their observations that macromolecular crowding can lead to robustness in gene expression, resulting in a more homogeneous cell population...
November 2016: PLoS Computational Biology
https://www.readbyqxmd.com/read/27881324/bacterial-adhesion-on-direct-and-indirect-dental-restorative-composite-resins-an-in%C3%A2-vitro-study-on-a-natural-biofilm
#8
Giacomo Derchi, Michele Vano, Antonio Barone, Ugo Covani, Alberto Diaspro, Marco Salerno
STATEMENT OF PROBLEM: Both direct and indirect techniques are used for dental restorations. Which technique should be preferred or whether they are equivalent with respect to bacterial adhesion is unclear. PURPOSE: The purpose of this in vitro study was to determine the affinity of bacterial biofilm to dental restorative composite resins placed directly and indirectly. MATERIAL AND METHODS: Five direct composite resins for restorations (Venus Diamond, Adonis, Optifil, Enamel Plus HRi, Clearfil Majesty Esthetic) and 3 indirect composite resins (Gradia, Estenia, Signum) were selected...
October 27, 2016: Journal of Prosthetic Dentistry
https://www.readbyqxmd.com/read/27866239/diffusion-kurtosis-imaging-and-diffusion-weighted-imaging-in-assessment-of-liver-fibrosis-stage-and-necroinflammatory-activity
#9
Ruo Fan Sheng, He Qing Wang, Li Yang, Kai Pu Jin, Yan Hong Xie, Cai Zhong Chen, Meng Su Zeng
PURPOSE: To investigate and compare the diagnostic value of diffusion kurtosis imaging (DKI) with diffusion-weighted imaging (DWI) in assessing and quantifying hepatic fibrosis. METHODS: Thirty rats were divided into the control group (n = 6) and the fibrosis experimental groups (n = 6 per group) with CCl4 administration for 2, 4, 6, and 8 weeks. Liver fibrosis stage (S) and necroinflammatory activity grade (G) were histopathologically determined. DKI and DWI were performed; mean apparent diffusion (MD), mean kurtosis (MK), and apparent diffusion coefficient (ADC) values were calculated...
November 19, 2016: Abdominal Radiology
https://www.readbyqxmd.com/read/27862632/morphological-changes-induced-in-erythrocyte-membrane-by-the-antiepileptic-treatment-an-atomic-force-microscopy-study
#10
Bogdan Oprisan, Iuliana Stoica, Mihaela Iuliana Avadanei
Atomic force microscopy (AFM), a powerful characterization tool widely applied in problems in a large range of disciplines of the natural sciences, including cellular biology, was used to obtain information about the morphological changes induced in the erythrocyte membrane at the patients with epilepsy that undergo a long time treatment that operates upon one or several neuronal ionic channels, comparative with a healthy donor. This technique allowed non-invasive imaging of erythrocyte membrane, revealing details and specific characteristics down to the nanometer level with characterization of surface texture parameters, such as average height, average roughness and coefficient of kurtosis at micrometer/nanometer resolution...
November 12, 2016: Microscopy Research and Technique
https://www.readbyqxmd.com/read/27862582/whole-tumor-mri-histogram-analyses-of-hepatocellular-carcinoma-correlations-with-ki-67-labeling-index
#11
Xin-Xing Hu, Zhao-Xia Yang, He-Yue Liang, Ying Ding, Robert Grimm, Cai-Xia Fu, Hui Liu, Xu Yan, Yuan Ji, Meng-Su Zeng, Sheng-Xiang Rao
PURPOSE: To evaluate whether whole-tumor histogram-derived parameters for an apparent diffusion coefficient (ADC) map and contrast-enhanced magnetic resonance imaging (MRI) could aid in assessing Ki-67 labeling index (LI) of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: In all, 57 patients with HCC who underwent pretreatment MRI with a 3T MR scanner were included retrospectively. Histogram parameters including mean, median, standard deviation, skewness, kurtosis, and percentiles (5(th) , 25(th) , 75(th) , 95(th) ) were derived from the ADC map and MR enhancement...
November 10, 2016: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/27834215/diffusion-weighted-imaging-uncovers-likely-sources-of-processing-speed-deficits-in-schizophrenia
#12
Peter Kochunov, Laura M Rowland, Els Fieremans, Jelle Veraart, Neda Jahanshad, George Eskandar, Xiaoming Du, Florian Muellerklein, Anya Savransky, Dinesh Shukla, Hemalatha Sampath, Paul M Thompson, L Elliot Hong
Schizophrenia, a devastating psychiatric illness with onset in the late teens to early 20s, is thought to involve disrupted brain connectivity. Functional and structural disconnections of cortical networks may underlie various cognitive deficits, including a substantial reduction in the speed of information processing in schizophrenia patients compared with controls. Myelinated white matter supports the speed of electrical signal transmission in the brain. To examine possible neuroanatomical sources of cognitive deficits, we used a comprehensive diffusion-weighted imaging (DWI) protocol and characterized the white matter diffusion signals using diffusion kurtosis imaging (DKI) and permeability-diffusivity imaging (PDI) in patients (n = 74), their nonill siblings (n = 41), and healthy controls (n = 113)...
November 22, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27825037/evaluation-of-histopathological-changes-in-the-microstructure-at-the-center-and-periphery-of-glioma-tumors-using-diffusional-kurtosis-imaging
#13
Fuyan Li, Wenqi Shi, Dawei Wang, Yanjie Xu, Hongxia Li, Jingzhen He, Qingshi Zeng
OBJECTIVE: To explore the relationship between alterations in gliomas revealed by diffusional kurtosis imaging (DKI) and the histopathological microstructural changes. METHODS: Thirty-seven patients with cerebral gliomas underwent conventional MRI and DKI at 3.0T. Normalized fractional anisotropy (FA), mean diffusivity (MD) and mean kurtosis (MK) were compared in different regions of glioma tumors. Parameters with a high sensitivity and specificity regarding the discrimination of glioma grade were evaluated using receiver operating characteristic (ROC) curve analysis...
October 27, 2016: Clinical Neurology and Neurosurgery
https://www.readbyqxmd.com/read/27824875/effect-of-hydrofluoric-acid-etching-time-on-titanium-topography-chemistry-wettability-and-cell-adhesion
#14
R Zahran, J I Rosales Leal, M A Rodríguez Valverde, M A Cabrerizo Vílchez
Titanium implant surface etching has proven an effective method to enhance cell attachment. Despite the frequent use of hydrofluoric (HF) acid, many questions remain unresolved, including the optimal etching time and its effect on surface and biological properties. The objective of this study was to investigate the effect of HF acid etching time on Ti topography, surface chemistry, wettability, and cell adhesion. These data are useful to design improved acid treatment and obtain an improved cell response. The surface topography, chemistry, dynamic wetting, and cell adhesiveness of polished Ti surfaces were evaluated after treatment with HF acid solution for 0, 2; 3, 5, 7, or 10 min, revealing a time-dependent effect of HF acid on their topography, chemistry, and wetting...
2016: PloS One
https://www.readbyqxmd.com/read/27818577/parameter-estimation-error-dependency-on-the-acquisition-protocol-in-diffusion-kurtosis-imaging
#15
Nima Gilani, Paul N Malcolm, Glyn Johnson
Mono-exponential kurtosis model is routinely fitted on diffusion weighted, magnetic resonance imaging data to describe non-Gaussian diffusion. Here, the purpose was to optimize acquisitions for this model to minimize the errors in estimating diffusion coefficient and kurtosis. Similar to a previous study, covariance matrix calculations were used, and coefficients of variation in estimating each parameter of this model were calculated. The acquisition parameter, b values, varied in discrete grids to find the optimum ones that minimize the coefficient of variation in estimating the two non-Gaussian parameters...
2016: Applied Magnetic Resonance
https://www.readbyqxmd.com/read/27812141/intraday-seasonalities-and-nonstationarity-of-trading-volume-in-financial-markets-individual-and-cross-sectional-features
#16
Michelle B Graczyk, Sílvio M Duarte Queirós
We study the intraday behaviour of the statistical moments of the trading volume of the blue chip equities that composed the Dow Jones Industrial Average index between 2003 and 2014. By splitting that time interval into semesters, we provide a quantitative account of the nonstationary nature of the intraday statistical properties as well. Explicitly, we prove the well-known ∪-shape exhibited by the average trading volume-as well as the volatility of the price fluctuations-experienced a significant change from 2008 (the year of the "subprime" financial crisis) onwards...
2016: PloS One
https://www.readbyqxmd.com/read/27811395/sparse-representation-based-ecg-signal-enhancement-and-qrs-detection
#17
Yichao Zhou, Xiyuan Hu, Zhenmin Tang, Andrew C Ahn
Electrocardiogram (ECG) signal enhancement and QRS complex detection is a critical preprocessing step for further heart disease analysis and diagnosis. In this paper, we propose a sparse representation-based ECG signal enhancement and QRS complex detection algorithm. Unlike traditional Fourier or wavelet transform-based methods, which use fixed bases, the proposed algorithm models the ECG signal as the superposition of a few inner structures plus additive random noise, where these structures (referred to here as atoms) can be learned from the input signal or a training set...
November 4, 2016: Physiological Measurement
https://www.readbyqxmd.com/read/27807795/can-we-shorten-the-q-space-imaging-to-make-it-clinically-feasible
#18
Koji Sakai, Kei Yamada, Kentaro Akazawa, Jun Tazoe, Masashi Yasuike, Hitomi Nagano, Hiroyasu Ikeno, Toshiaki Nakagawa
PURPOSE: Q-space imaging (QSI) is a novel magnetic resonance imaging (MRI) technique that enables assessment of micro-structural changes of white matter. The acquisition time, however, is comparatively long to use for routine clinical assessment. Therefore, the present study investigated the clinically feasible b value combinations to measure the water molecular displacement probability density function (PDF) in healthy subjects. METHODS: The subjects consisted of five healthy volunteers (1 female and 4 male; 40...
November 2, 2016: Japanese Journal of Radiology
https://www.readbyqxmd.com/read/27804074/mechanical-dyssynchrony-according-to-validated-cut-off-values-using-gated-spect-myocardial-perfusion-imaging
#19
Santiago Aguadé-Bruix, Guillermo Romero-Farina, Jaume Candell-Riera, María N Pizzi, David García-Dorado
BACKGROUND: The aim of this study was to establish different degrees of mechanical dyssynchrony according to validated cut-off (CO) values of myocardial perfusion gated SPECT phase analysis parameters (SD, standard deviation; B, bandwidth; S, skewness; K, kurtosis). METHODS: Using Emory Cardiac Toolbox™, we prospectively analyzed 408 patients (mean age 64.1 years, 26.7% female), divided into a control group of 150 normal subjects and a validation group of 258 patients (left bundle branch block: 17...
November 1, 2016: Journal of Nuclear Cardiology: Official Publication of the American Society of Nuclear Cardiology
https://www.readbyqxmd.com/read/27802700/response-measurement-by-laser-doppler-vibrometry-in-vibration-qualification-tests-with-non-gaussian-random-excitation
#20
M Troncossi, R Di Sante, A Rivola
In the field of vibration qualification testing, random excitations are typically imposed on the tested system in terms of a power spectral density (PSD) profile. This is the one of the most popular ways to control the shaker or slip table for durability tests. However, these excitations (and the corresponding system responses) exhibit a Gaussian probability distribution, whereas not all real-life excitations are Gaussian, causing the response to be also non-Gaussian. In order to introduce non-Gaussian peaks, a further parameter, i...
October 2016: Review of Scientific Instruments
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