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https://www.readbyqxmd.com/read/29775912/an-accurate-sleep-stages-classification-system-using-a-new-class-of-optimally-time-frequency-localized-three-band-wavelet-filter-bank
#1
Manish Sharma, Deepanshu Goyal, P V Achuth, U Rajendra Acharya
Sleep related disorder causes diminished quality of lives in human beings. Sleep scoring or sleep staging is the process of classifying various sleep stages which helps to detect the quality of sleep. The identification of sleep-stages using electroencephalogram (EEG) signals is an arduous task. Just by looking at an EEG signal, one cannot determine the sleep stages precisely. Sleep specialists may make errors in identifying sleep stages by visual inspection. To mitigate the erroneous identification and to reduce the burden on doctors, a computer-aided EEG based system can be deployed in the hospitals, which can help identify the sleep stages, correctly...
May 10, 2018: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/29767529/fractal-gold-nanoframework-for-highly-stretchable-transparent-strain-insensitive-conductors
#2
My Duyen Ho, Yiyi Liu, Dashen Dong, Yunmeng Zhao, Wenlong Cheng
Percolation networks of one-dimensional (1D) building blocks (e.g., metallic nanowires or carbon nanotubes) represent the mainstream strategy to fabricate stretchable conductors. One of the inherent limitations is the control over junction resistance between 1D building blocks in natural and strained states of conductors. Herein, we report highly stretchable transparent strain-insensitive conductors using fractal gold (F-Au) nanoframework based on a one-pot templateless wet chemistry synthesis method. The monolayered F-Au nanoframework (∼20 nm in thickness) can be obtained from the one-pot synthesis without any purification steps involved and can be transferred directly to arbitrary substrates like polyethylene terephthalate, food-wrap, polydimethylsiloxane (PDMS), and ecoflex...
May 16, 2018: Nano Letters
https://www.readbyqxmd.com/read/29766452/a-novel-technique-for-visualizing-and-analyzing-the-cerebral-vasculature-in-rodents
#3
Arjang Salehi, Amandine Jullienne, Kara M Wendel, Mary Hamer, Jiping Tang, John H Zhang, William J Pearce, Richard A DeFazio, Zinaida S Vexler, Andre Obenaus
We introduce a novel protocol to stain, visualize, and analyze blood vessels from the rat and mouse cerebrum. This technique utilizes the fluorescent dye, DiI, to label the lumen of the vasculature followed by perfusion fixation. Following brain extraction, the labeled vasculature is then imaged using wide-field fluorescence microscopy for axial and coronal images and can be followed by regional confocal microscopy. Axial and coronal images can be analyzed using classical angiographic methods for vessel density, length, and other features...
May 15, 2018: Translational Stroke Research
https://www.readbyqxmd.com/read/29765109/microvascular-fractal-dimension-predicts-prognosis-and-response-to-chemotherapy-in-glioblastoma-an-automatic-image-analysis-study
#4
Cong Chen, Zhi-Cheng He, Yu Shi, Wenchao Zhou, Xia Zhang, Hua-Liang Xiao, Hai-Bo Wu, Xiao-Hong Yao, Wan-Chun Luo, You-Hong Cui, Shideng Bao, Hsiang-Fu Kung, Xiu-Wu Bian, Yi-Fang Ping
The microvascular profile has been included in the WHO glioma grading criteria. Nevertheless, microvessels in gliomas of the same WHO grade, e.g., WHO IV glioblastoma (GBM), exhibit heterogeneous and polymorphic morphology, whose possible clinical significance remains to be determined. In this study, we employed a fractal geometry-derived parameter, microvascular fractal dimension (mvFD), to quantify microvessel complexity and developed a home-made macro in Image J software to automatically determine mvFD from the microvessel-stained immunohistochemical images of GBM...
May 15, 2018: Laboratory Investigation; a Journal of Technical Methods and Pathology
https://www.readbyqxmd.com/read/29763547/tracer-transport-probes-relaxation-and-structure-of-attractive-and-repulsive-glassy-liquids
#5
Ryan C Roberts, Ryan Poling-Skutvik, Jeremy C Palmer, Jacinta C Conrad
Dynamic coupling of small penetrants to slow, cooperative relaxations within crowded cells, supercooled liquids, and polymer matrices has broad consequences for applications ranging from drug delivery to nanocomposite processing. Interactions between the constituents of these and other disordered media alter the cooperative relaxations, but their effect on penetrant dynamics remains incompletely understood. We use molecular dynamics simulations to show that the motions of hard-sphere tracer particles probe differences in local structure and cooperative relaxation processes in attractive and repulsive glassy liquid matrices with equal bulk packing fractions and long-time diffusivities...
May 15, 2018: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/29761603/a-sticky-mucin-inspired-dna-polysaccharide-binder-for-silicon-and-silicon-graphite-blended-anodes-in-lithium-ion-batteries
#6
Sunjin Kim, You Kyeong Jeong, Younseon Wang, Haeshin Lee, Jang Wook Choi
New binder concepts have lately demonstrated improvements in the cycle life of high-capacity silicon anodes. Those binder designs adopt adhesive functional groups to enhance affinity with silicon particles and 3D network conformation to secure electrode integrity. However, homogeneous distribution of silicon particles in the presence of a substantial volumetric content of carbonaceous components (i.e., conductive agent, graphite, etc.) is still difficult to achieve while the binder maintains its desired 3D network...
May 14, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29758870/effect-of-the-micro-flocculation-stage-on-the-flocculation-sedimentation-process-the-role-of-shear-rate
#7
Zhenbei Wang, Jun Nan, Xiaoyu Ji, Yueming Yang
Dynamic analysis on the variation of particle size distribution (PSD) and the fractal characteristics of PSD (Df ) were investigated to better understand the continuous procedure of the floc growth and optimize the control of flocculation process. It was found that the flocculation process could be divided into three stages, i.e., the micro-flocculation stage, the growth stage and the steady (or breakage) stage. As the stage which is crucial to the morphology of micro-flocs (the building blocks of large flocs), the micro-flocculation stage plays an important role on flocculation/sedimentation process...
August 15, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29758738/open-quantum-maps-from-complex-scaling-of-kicked-scattering-systems
#8
Normann Mertig, Akira Shudo
We derive open quantum maps from periodically kicked scattering systems and discuss the computation of their resonance spectra in terms of theoretically grounded methods, such as complex scaling and sufficiently weak absorbing potentials. In contrast, we also show that current implementations of open quantum maps, based on strong absorptive or even projective openings, fail to produce the resonance spectra of kicked scattering systems. This comparison pinpoints flaws in current implementations of open quantum maps, namely, the inability to separate resonance eigenvalues from the continuum as well as the presence of diffraction effects due to strong absorption...
April 2018: Physical Review. E
https://www.readbyqxmd.com/read/29758691/self-avoiding-walk-on-a-square-lattice-with-correlated-vacancies
#9
J Cheraghalizadeh, M N Najafi, H Mohammadzadeh, A Saber
The self-avoiding walk on the square site-diluted correlated percolation lattice is considered. The Ising model is employed to realize the spatial correlations of the metric space. As a well-accepted result, the (generalized) Flory's mean-field relation is tested to measure the effect of correlation. After exploring a perturbative Fokker-Planck-like equation, we apply an enriched Rosenbluth Monte Carlo method to study the problem. To be more precise, the winding angle analysis is also performed from which the diffusivity parameter of Schramm-Loewner evolution theory (κ) is extracted...
April 2018: Physical Review. E
https://www.readbyqxmd.com/read/29757656/multilevel-morphology-of-complex-nanoporous-materials
#10
Ahmad Motahari, Naiping Hu, Amir Vahid, Abdollah Omrani, Abbas Ali Rostami, Dale W Schaefer
This work exploits gas adsorption and small-angle X-ray scattering (SAXS) to illuminate morphology of complex nanoporous materials. We resolve multiple classes of porosity including previously undetected large-scale texture that significantly compromises the canonical interpretation of gas adsorption. Specifically, a UVM-7 class mesoporous silica was synthesized that has morphological features on three length scales: macropores due to packing of 150-nm globules, 1.9-nm-radius spherical mesopores inside the globules and >7-nm pockets on and between the globules...
May 14, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29757165/absence-of-2-5-power-law-for-fractal-packing-in-metallic-glasses
#11
Jianrui Feng, Pengwan Chen, Mo Li
Atomic packing is still a mystery for the topologically disordered amorphous solids owing primarily to the absence of Bragg diffraction in this class of materials. Among many hypotheses, a fractal packing is suggested based on a scaling relation with "2.5 power law" in multicomponent metallic glasses. Here we examine the atomic packing critically in a pure Tantalum metallic glass under hydrostatic pressure. Without any complications of chemical compositions as in the multicomponent systems, the genuine amorphous structure in the single component metallic glass exhibits cubic scaling exponent that indicates absence of the 2...
May 14, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/29756808/elastic-backbone-defines-a-new-transition-in-the-percolation-model
#12
Cesar I N Sampaio Filho, José S Andrade, Hans J Herrmann, André A Moreira
The elastic backbone is the set of all shortest paths. We found a new phase transition at p_{eb} above the classical percolation threshold at which the elastic backbone becomes dense. At this transition in 2D, its fractal dimension is 1.750±0.003, and one obtains a novel set of critical exponents β_{eb}=0.50±0.02, γ_{eb}=1.97±0.05, and ν_{eb}=2.00±0.02, fulfilling consistent critical scaling laws. Interestingly, however, the hyperscaling relation is violated. Using Binder's cumulant, we determine, with high precision, the critical probabilities p_{eb} for the triangular and tilted square lattice for site and bond percolation...
April 27, 2018: Physical Review Letters
https://www.readbyqxmd.com/read/29755183/regularized-laplacian-determinants-of-self-similar-fractals
#13
Joe P Chen, Alexander Teplyaev, Konstantinos Tsougkas
We study the spectral zeta functions of the Laplacian on fractal sets which are locally self-similar fractafolds, in the sense of Strichartz. These functions are known to meromorphically extend to the entire complex plane, and the locations of their poles, sometimes referred to as complex dimensions, are of special interest. We give examples of locally self-similar sets such that their complex dimensions are not on the imaginary axis, which allows us to interpret their Laplacian determinant as the regularized product of their eigenvalues...
2018: Letters in Mathematical Physics
https://www.readbyqxmd.com/read/29751269/manipulating-the-fractal-fiber-network-of-a-molecular-gel-with-surfactants
#14
Jing-Yu Chen, Zahra Komeily-Nia, Lin-Peng Fan, Zhen-Yu Li, Bing Yuan, Bin Tang, Jing-Liang Li
Supramolecular assembly governs the formation and properties of many soft materials. Hence, it is significant to develop convenient approaches to control the assembly process. In this work, it is demonstrated that by using surfactants consisting of a sorbitan group (either ethoxylated or not) and an aliphatic chain, as additives, the fractal fiber network structure of a π gelator (with two alkyl chains) can be engineered. The two surfactants, which have the same hydrophobic tails but different hydrophilic heads, demonstrate different effects on the fiber network of the gelator...
May 5, 2018: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/29749593/a-cortical-study-of-the-attention-in-military-simulation-tests
#15
M A Idiazabal-Alecha, M V Sebastian-Guerrero, M A Navascues-Sanagustin, C Arcos-Sanchez, M V Arana-Aritmendiz, C Ruiz-Lopez, J M Iso-Perez
INTRODUCTION: Attention is one of the most widely studied superior cerebral functions and base of many other cognitive processes. It is sometimes understood as concentration on a task or target. The level of execution of a task and the ability to process information are dependent on the state of cerebral activation of the subject. This brain activity can be recorded with the electroencephalogram (EEG). AIM: Attention is studied in states of rest and during the performance of tasks in military personnel, exploring the differences between two groups (cadets and officers/NCOs)...
May 16, 2018: Revista de Neurologia
https://www.readbyqxmd.com/read/29747045/habitat-selection-of-intertidal-caprellid-amphipods-in-a-changing-scenario
#16
G Martínez-Laiz, M Ros, C Navarro-Barranco, J M Guerra-García
Habitat selection is a complex process, dependent on numerous fluctuating conditions and key to species coexistence. In a changing global scenario, it will greatly determine the fate of marine organisms and hence is an important subject to be explored. The present study evaluates host specificity of two caprellid amphipod species, Caprella grandimana and Caprella takeuchii, dwelling on a rocky intertidal where the calcifying macroalgae Jania rubens and Ellisolandia elongata show opposite seasonal fluctuation patterns throughout the year...
May 7, 2018: Behavioural Processes
https://www.readbyqxmd.com/read/29741547/microenvironmental-influence-on-microtumour-infiltration-patterns-3d-mathematical-modelling-supported-by-in-vitro-studies
#17
Emmanuel Luján, Daniela Soto, María S Rosito, Alejandro Soba, Liliana N Guerra, Juan C Calvo, Guillermo Marshall, Cecilia Suárez
Mathematical modelling approaches have become increasingly abundant in cancer research. Tumour infiltration extent and its spatial organization depend both on the tumour type and stage and on the bio-physicochemical characteristics of the microenvironment. This sets a complex scenario that often requires a multidisciplinary and individually adjusted approach. The ultimate goal of this work is to present an experimental/numerical combined method for the development of a three-dimensional mathematical model with the ability to reproduce the growth and infiltration patterns of a given avascular microtumour in response to different microenvironmental conditions...
May 9, 2018: Integrative Biology: Quantitative Biosciences From Nano to Macro
https://www.readbyqxmd.com/read/29740278/modeling-the-improved-visual-acuity-using-photodiode-based-retinal-implants-featuring-fractal-electrodes
#18
William J Watterson, Rick D Montgomery, Richard P Taylor
Electronically restoring vision to patients blinded by severe retinal degenerations is rapidly becoming a realizable feat through retinal implants. Upon receiving an implant, previously blind patients can now detect light, locate objects, and determine object motion direction. However, the restored visual acuity (VA) is still significantly below the legal blindness level (VA < 20/200). The goal of this research is to optimize the inner electrode geometry in photovoltaic subretinal implants in order to restore vision to a VA better than blindness level...
2018: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/29738957/performance-of-an-attention-demanding-task-during-treadmill-walking-shifts-the-noise-qualities-of-step-to-step-variation-in-step-width
#19
Mark D Grabiner, Jane R Marone, Marilynn Wyatt, Pinata Sessoms, Kenton R Kaufman
BACKGROUND: The fractal scaling evident in the step-to-step fluctuations of stepping-related time series reflects, to some degree, neuromotor noise. RESEARCH QUESTION: The primary purpose of this study was to determine the extent to which the fractal scaling of step width, step width and step width variability are affected by performance of an attention-demanding task. We hypothesized that the attention-demanding task would shift the structure of the step width time series toward white, uncorrelated noise...
April 30, 2018: Gait & Posture
https://www.readbyqxmd.com/read/29736393/relationship-between-isometric-muscle-force-and-fractal-dimension-of-surface-electromyogram
#20
Matteo Beretta-Piccoli, Gennaro Boccia, Tessa Ponti, Ron Clijsen, Marco Barbero, Corrado Cescon
The relationship between fractal dimension of the surface electromyogram (sEMG) and the intensity of muscle contraction is still controversial in simulated and experimental conditions. To support the use of fractal analysis to investigate myoelectric fatigue, it is crucial to establish the interdependence between fractal dimension and muscle contraction intensity. We analyzed the behavior of fractal dimension, conduction velocity, mean frequency, and average rectified value in twenty-eight volunteers at nine levels of isometric force...
2018: BioMed Research International
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