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https://www.readbyqxmd.com/read/28434153/machine-learning-xgboost-analysis-of-language-networks-to-classify-patients-with-epilepsy
#1
L Torlay, M Perrone-Bertolotti, E Thomas, M Baciu
Our goal was to apply a statistical approach to allow the identification of atypical language patterns and to differentiate patients with epilepsy from healthy subjects, based on their cerebral activity, as assessed by functional MRI (fMRI). Patients with focal epilepsy show reorganization or plasticity of brain networks involved in cognitive functions, inducing 'atypical' (compared to 'typical' in healthy people) brain profiles. Moreover, some of these patients suffer from drug-resistant epilepsy, and they undergo surgery to stop seizures...
April 22, 2017: Brain Informatics
https://www.readbyqxmd.com/read/28434062/nlophoric-3-6-di-substituted-quinoxalin-carbazoles-synthesis-photophysical-properties-and-dft-studies
#2
Rahul D Telore, Amol G Jadhav, Nagaiyan Sekar
Synthesis of novel 3,6-di(substituted quinoxalin) carbazole fluorophores by the condensation of 1,1'-(9-ethyl-9H-carbazole-3,6-diyl)bis(2-bromoethanone) with methyl, chloro and unsubstituted o-phenylenediamine is presented. Synthesized derivatives are well characterized by (1)H NMR, (13)C NMR, FTIR and Mass spectroscopy. Photophysical studies are carried out using solvents of varying polarities revealed positive solvatochromism and intramolecular charge transfer from carbazole (Donor) to quinoxalin (Acceptor)...
April 22, 2017: Journal of Fluorescence
https://www.readbyqxmd.com/read/28433947/maximum-likelihood-estimation-of-cardiac-fiber-bundle-orientation-from-arbitrarily-spaced-diffusion-weighted-images
#3
Andreas Nagler, Cristóbal Bertoglio, Christian T Stoeck, Sebastian Kozerke, Wolfgang A Wall
We propose an estimation scheme for local fiber bundle direction in the left ventricle directly from gray values of arbitrarily spaced cardiac diffusion weighted images (DWI). The approach is based on a parametric and space-dependent mathematical representation of the myocardial fiber bundle orientation and hence the diffusion tensor (DT) for the ventricular geometry. By solving a nonlinear inverse problem derived from a maximum likelihood estimator, the degrees of freedom of the fiber and DT model can be estimated from the measured gray values of the DWIs...
April 4, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28433810/generation-mechanism-of-nonlinear-ultrasonic-lamb-waves-in-thin-plates-with-randomly-distributed-micro-cracks
#4
Youxuan Zhao, Feilong Li, Peng Cao, Yaolu Liu, Jianyu Zhang, Shaoyun Fu, Jun Zhang, Ning Hu
Since the identification of micro-cracks in engineering materials is very valuable in understanding the initial and slight changes in mechanical properties of materials under complex working environments, numerical simulations on the propagation of the low frequency S0 Lamb wave in thin plates with randomly distributed micro-cracks were performed to study the behavior of nonlinear Lamb waves. The results showed that while the influence of the randomly distributed micro-cracks on the phase velocity of the low frequency S0 fundamental waves could be neglected, significant ultrasonic nonlinear effects caused by the randomly distributed micro-cracks was discovered, which mainly presented as a second harmonic generation...
April 12, 2017: Ultrasonics
https://www.readbyqxmd.com/read/28433019/tests-for-origins-of-and-corrections-to-non-gaussian-statistics-the-dipole-flip-model
#5
Addison J Schile, Ward H Thompson
Linear response approximations are central to our understanding and simulations of nonequilibrium statistical mechanics. Despite the success of these approaches in predicting nonequilibrium dynamics, open questions remain. Laird and Thompson [J. Chem. Phys. 126, 211104 (2007)] previously formalized, in the context of solvation dynamics, the connection between the static linear-response approximation and the assumption of Gaussian statistics. The Gaussian statistics perspective is useful in understanding why linear response approximations are still accurate for perturbations much larger than thermal energies...
April 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28433008/nonlinear-permittivity-spectra-of-supercooled-ionic-liquids-observation-of-a-hump-in-the-third-order-permittivity-spectra-and-comparison-to-double-well-potential-models
#6
L N Patro, O Burghaus, B Roling
We have measured the third-order permittivity spectra ε3(3) of a monocationic and of a dicationic liquid close to the glass transition temperature by applying ac electric fields with large amplitudes up to 180 kV/cm. A peak ("hump") in the modulus of ε3(3) is observed for a mono-cationic liquid after subtraction of the dc contribution from the imaginary part of ε3(3). We show that the origin of this experimental "hump" is a peak in the imaginary part of ε3(3), with the peak height strongly increasing with decreasing temperature...
April 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28432998/non-ideal-effects-in-bending-response-of-soft-substrates-covered-with-biomimetic-scales
#7
Ranajay Ghosh, Hamid Ebrahimi, Ashkan Vaziri
Biomimetic scales are known to substantially alter the mechanics response of the underlying substrate engendering complex nonlinearities that can manifest even in small deformations due to scales interaction. This interaction is typically modeled using a-priori homogenization with an enforced periodicity of engagement. Such a framework is fairly useful especially when dealing with the structural length scale which is at least one order of magnitude greater than the scales themselves since individual tracking of a large number of scales become insurmountable...
April 15, 2017: Journal of the Mechanical Behavior of Biomedical Materials
https://www.readbyqxmd.com/read/28432770/chiral-separation-of-aryloxyphenoxy-propionate-herbicides-in-a-permethyl-%C3%AE-cyclodextrin-based-column-influence-of-temperature-and-mobile-phase-composition-on-enantioselectivity
#8
Ester Lubomirsky, Héctor Di Loreto, Juan M Padró, Cecilia B Castells
We used a permethyl-β-cyclodextrin chiral stationary phase under reversed-phase conditions for the chiral separation of four aryloxyphenoxy-propionate herbicides (fenoxaprop-p-ethyl, quizalofop-p-ethyl and tefuryl and haloxyfop-p-methyl) with mixtures of methanol, ethanol, 2-propanol, n-propanol, tert-butanol, or acetonitrile and water as mobile phases and investigated the influence of mobile phase composition and column temperature (from 0 to 50 °C) on the separation. The retention factors (k) and selectivity factors (α) of all the herbicides investigated decreased with increasing temperature...
April 22, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28432685/chiral-analysis-of-%C3%AE-diimine-ru-ii-and-fe-ii-complexes-by-capillary-electrophoresis-using-sulfated-cyclodextrins-as-stereoselectors
#9
Petra Sázelová, Dušan Koval, Lukáš Severa, Filip Teplý, Václav Kašička
Capillary electrophoresis (CE) using randomly highly sulfated α-, β-, and γ-cyclodextrins (S-α-CD, S-β-CD, S-γ-CD), sulfobutylether-β-CD (SBE-β-CD), single isomer (6-O-sulfo) α-, β-, and γ-CDs and their derivatives as stereoselectors was applied to chiral analysis of polypyridyl complexes of [Ru(bpy)3 ](2+) , [Ru(phen)3 ](2+) , and [Fe(phen)3 ](2+) (bpy = 2,2'-bipyridine; phen = 1,10 phenanthroline). The best separations of Δ- and Λ-enantiomers of the these complexes with high resolution (up to R1,2  = 7...
April 22, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28432621/comparison-of-air-pollution-in-shanghai-and-lanzhou-based-on-wavelet-transform
#10
Yana Su, Yongzhong Sha, Guangyu Zhai, Shengliang Zong, Jiehua Jia
For a long-period comparative analysis of air pollution in coastal and inland cities, we analyzed the continuous Morlet wavelet transform on the time series of a 5274-day air pollution index in Shanghai and Lanzhou during 15 years and studied the multi-scale variation characteristic, main cycle, and impact factor of the air pollution time series. The analysis showed that (1) air pollution in the two cities was non-stationary and nonlinear, had multiple timescales, and exhibited the characteristics of high in winter and spring and low in summer and autumn...
April 21, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28432468/population-pharmacokinetics-of-intravenous-acetaminophen-in-japanese-patients-undergoing-elective-surgery
#11
Tsuyoshi Imaizumi, Shinju Obara, Midori Mogami, Yuzo Iseki, Makiko Hasegawa, Masahiro Murakawa
INTRODUCTION: Intravenous (i.v.) acetaminophen is administered during surgery for postoperative analgesia. However, little information is available on the pharmacokinetics of i.v. acetaminophen in Japanese patients undergoing surgery under general anesthesia. METHODS: The study was approved by the Institutional Review Board and registered at UMIN-CTR (UMIN000013418). Patients scheduled to undergo elective surgery under general anesthesia were enrolled after obtaining written informed consent...
April 21, 2017: Journal of Anesthesia
https://www.readbyqxmd.com/read/28432057/imaging-and-modeling-of-acute-pressure-induced-changes-of-collagen-and-elastin-microarchitectures-in-pig-and-human-resistance-arteries
#12
Maria Bloksgaard, Thomas M Leurgans, Bart Spronck, Maarten Hg Heusinkveld, Bjarne Thorsted, Kristoffer Rosenstand, Inger Nissen, Ulla Melchior Hansen, Jonathan R Brewer, Luis A Bagatolli, Lars M Rasmussen, Akhmadjon Irmukhamedov, Koen D Reesink, Jo G R De Mey
The impact of disease related changes in the extracellular matrix (ECM) on the mechanical properties of human resistance arteries largely remains to be established. Resistance arteries from both pig and human parietal pericardium (PRA) display a different ECM microarchitecture compared to frequently used rodent mesenteric arteries. We hypothesized that the biaxial mechanics of PRA mirror pressure induced changes in the ECM microarchitecture. This was tested using isolated pig PRA as model system, integrating vital imaging, pressure myography and mathematical modeling...
April 21, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28431306/difference-optimization-automatic-correction-of-relative-frequency-and-phase-for-mean-non-edited-and-edited-gaba-1-h-mega-press-spectra
#13
Marianne Cleve, Martin Krämer, Alexander Gussew, Jürgen R Reichenbach
Phase and frequency corrections of magnetic resonance spectroscopic data are of major importance to obtain reliable and unambiguous metabolite estimates as validated in recent research for single-shot scans with the same spectral fingerprint. However, when using the J-difference editing technique (1)H MEGA-PRESS, misalignment between mean edited (ON‾) and non-edited (OFF‾) spectra that may remain even after correction of the corresponding individual single-shot scans results in subtraction artefacts compromising reliable GABA quantitation...
April 7, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28430474/dispersion-management-of-propagating-waveguide-modes-on-the-water-surface
#14
Shenhe Fu, Jianying Zhou, Yongyao Li, Lev Shemer, Ady Arie
We report on the theoretical and experimental study of the generation of propagating waveguide modes on the water surface. These propagating modes are modulated in the transverse direction in a manner that satisfies boundary conditions on the walls of the water tank. It is shown that the propagating modes possess both anomalous and normal dispersion regimes, in contrast to the extensively studied zero mode that, in the case of deep water, only has normal dispersion with a fixed frequency independent dispersion coefficient...
April 7, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28430470/parametrically-tunable-soliton-induced-resonant-radiation-by-three-wave-mixing
#15
B B Zhou, X Liu, H R Guo, X L Zeng, X F Chen, H P Chung, Y H Chen, M Bache
We show that a temporal soliton can induce resonant radiation by three-wave mixing nonlinearities. This constitutes a new class of resonant radiation whose spectral positions are parametrically tunable. The experimental verification is done in a periodically poled lithium niobate crystal, where a femtosecond near-IR soliton is excited and resonant radiation waves are observed exactly at the calculated soliton phase-matching wavelengths via the sum- and difference-frequency generation nonlinearities. This extends the supercontinuum bandwidth well into the mid IR to span 550-5000 nm, and the mid-IR edge is parametrically tunable over 1000 nm by changing the three-wave mixing phase-matching condition...
April 7, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28430367/effect-of-dalteparin-administration-on-thrombin-generation-kinetics-in-healthy-dogs
#16
Carolyn Gara-Boivin, Jérôme R E Del Castillo, Marilyn E Dunn, Christian Bédard
BACKGROUND: Dalteparin is used to prevent thrombotic complications in dogs. Measurement of anti-factor Xa (anti-FXa) activity is currently used for monitoring therapy, but remains a nonfunctional test. The calibrated automated thrombogram (CAT) could be a suitable approach for functional monitoring. OBJECTIVES: We hypothesized that the CAT will detect decreased endogenous thrombin potential (ETP) in healthy dogs receiving dalteparin. METHODS: Twenty-four healthy adult Beagles were randomly allocated to 4 equal groups...
April 21, 2017: Veterinary Clinical Pathology
https://www.readbyqxmd.com/read/28430264/optimization-of-excitation-of-fiber-fabry-perot-tunable-filters-used-in-swept-lasers-using-a-phase-correction-method
#17
Mohammad R N Avanaki, Adrian Bradu, Adrian Podoleanu
In this paper we investigate a phase-correction method for compensation of the nonlinearity of conventional wavelength-swept laser sources based on a fiber Fabry-Perot tunable filter as a wavelength selective element. A triangular waveform signal is commonly used to drive the filter. We, however, extract the zero crossings from the interferograms and modify the shape of the triangular signal accordingly. This algorithm was tested for different values of the optical path length difference in the interferometer setup...
April 20, 2017: Applied Optics
https://www.readbyqxmd.com/read/28430255/widely-tunable-2%C3%A2-%C3%A2-%C3%AE-m-continuous-wave-and-mode-locked-fiber-laser
#18
Wanzhuo Ma, Tianshu Wang, Yan Zhang, Peng Liu, Yuwei Su, Qingsong Jia, Mingzhe Bi, Peng Zhang, Huilin Jiang
We propose and experimentally demonstrate a widely tunable mode-locked thulium-doped fiber laser. The laser can operate at both continuous-wave and mode-locked states at different pump power levels. A classic nonlinear polarization rotation structure is employed to obtain the passive mode-locked laser. A birefringence Lyot filter as a fiber comb filter is used to expand the tuning range. Thanks to the filtering component, the tuning range of the continuous-wave laser can reach 127 nm (1823-1950 nm). The tuning ranges of the single-wavelength and dual-wavelength mode-locked lasers are 94 nm (1835-1929 nm) and 87 nm (1831-1918 nm), respectively, with a 3...
April 20, 2017: Applied Optics
https://www.readbyqxmd.com/read/28430226/stable-nanosecond-passively-q-switched-all-fiber-erbium-doped-laser-with-a-45%C3%A2-tilted-fiber-grating
#19
Tianxing Wang, Zhijun Yan, Chengbo Mou, Kaiming Zhou, Lin Zhang
Nanosecond passive Q-switching generation from an all-fiber erbium-doped laser with a UV inscribed 45° tilted fiber grating (TFG) is systematically demonstrated. The 45° TFG is employed as a polarizer together with two polarization controllers (PCs) to realize nonlinear polarization rotation (NPR). Because of the NPR effect, stable Q-switched pulses with an average output power of 17.5 mW, a single pulse energy of 72.7 nJ, a repetition rate of 241 kHz, a pulse width of 466 ns, and a signal to noise ratio (SNR) of 58...
April 20, 2017: Applied Optics
https://www.readbyqxmd.com/read/28430186/independence-of-nutrient-limitation-and-carbon-dioxide-impacts-on-the-southern-ocean-coccolithophore-emiliania-huxleyi
#20
Marius N Müller, Thomas W Trull, Gustaaf M Hallegraeff
Future oceanic conditions induced by anthropogenic greenhouse gas emissions include warming, acidification and reduced nutrient supply due to increased stratification. Some parts of the Southern Ocean are expected to show rapid changes, especially for carbonate mineral saturation. Here we compare the physiological response of the model coccolithophore Emiliania huxleyi (strain EHSO 5.14, originating from 50(o)S, 149(o)E) with pH/CO2 gradients (mimicking ocean acidification ranging from 1 to 4 × current pCO2 levels) under nutrient-limited (nitrogen and phosphorus) and -replete conditions...
April 21, 2017: ISME Journal
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