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https://www.readbyqxmd.com/read/28734310/stability-limits-for-the-supercooled-liquid-and-superheated-crystal-of-lennard-jones-particles
#1
Ernesto S Loscar, Daniel A Martin, Tomás S Grigera
We have studied the limits of stability in the first order liquid-solid phase transition in a Lennard-Jones system by means of the short-time relaxation method and using the bond-orientational order parameter Q6. These limits are compared with the melting line. We have paid special attention to the supercooled liquid, comparing our results with the point where the free energy cost of forming a nucleating droplet goes to zero. We also indirectly estimate the dimension associated to the critical nucleus at the spinodal, expected to be fractal according to mean field theories of nucleation...
July 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28732697/cytological-study-of-dna-content-and-nuclear-morphometric-analysis-for-aid-in-the-diagnosis-of-high-grade-dysplasia-within-oral-leukoplakia
#2
Xi Yang, Xuan Xiao, Wenyan Wu, Xuemin Shen, Zengtong Zhou, Wei Liu, Linjun Shi
OBJECTIVE: To quantitatively examine the DNA content and nuclear morphometric status of oral leukoplakia (OL) and investigate its association with the degree of dysplasia in a cytologic study. STUDY DESIGN: Oral cytobrush biopsy was carried out to obtain exfoliative epithelial cells from lesions before scalpel biopsy at the same location in a blinded series of 70 patients with OL. Analysis of nuclear morphometry and DNA content status using image cytometry was performed with oral smears stained with the Feulgen-thionin method...
July 18, 2017: Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
https://www.readbyqxmd.com/read/28729538/geometric-heterogeneity-of-continental-shale-in-the-yanchang-formation-southern-ordos-basin-china
#3
Lihui Li, Beixiu Huang, Yufang Tan, Xiaolong Deng, Yanyan Li, Hu Zheng
Favorable prospects for the exploration of shale gas have been demonstrated in the Ordos Basin, China. Outcrop and core observations indicate that there are abundant laminas in the shale strata, which exert a great influence on hydro-fracture propagation, gas storage and fluid flow. In this study, the continental shale of the Chang 72 Member, collected from the south of Ordos Basin, was investigated to characterize the geometric heterogeneity. Laminas at multiple scales were observed and measured using conventional logging, borehole TV, core analysis, scanning electron microscopy, and the Particle and Crack Analysis System...
July 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28728059/iterative-variational-mode-decomposition-based-automated-detection-of-glaucoma-using-fundus-images
#4
Shishir Maheshwari, Ram Bilas Pachori, Vivek Kanhangad, Sulatha V Bhandary, U Rajendra Acharya
Glaucoma is one of the leading causes of permanent vision loss. It is an ocular disorder caused by increased fluid pressure within the eye. The clinical methods available for the diagnosis of glaucoma require skilled supervision. They are manual, time consuming, and out of reach of common people. Hence, there is a need for an automated glaucoma diagnosis system for mass screening. In this paper, we present a novel method for an automated diagnosis of glaucoma using digital fundus images. Variational mode decomposition (VMD) method is used in an iterative manner for image decomposition...
June 19, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28727219/fractal-crystals-hunting-the-hidden-dimension-in-nanoporous-materials
#5
Lei Wang, Shengcai Zhu, Meikun Shen, Haiwen Tian, Songhai Xie, Hongbin Zhang, Yahong Zhang, Yi Tang
Screw dislocation structure in crystal are origin of symmetry breaking in a wide range of dense phase crystals. Preparation of such analogous structure in framework phase crystals is of great importance in zeolites but still a challenge. On the basis of crystal structure-solving and model building, we found that the two specific intergrowths in MTW zeolite produce this complex fractal and spiral structure. With the structure determined parameters (spiral pitch h, screw angle θ and spatial angle ψ) of Burgers circuit, the screw dislocation structure can be constructed by two different dimensional intergrowth sections...
July 20, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28726714/performance-of-a-novel-recycling-magnetic-flocculation-membrane-filtration-process-for-tetracycline-polluted-surface-water-treatment
#6
Yufei Wang, Hui Jia, Hongwei Zhang, Jie Wang, Wenjin Liu
A recycling magnetic flocculation membrane filtration (RMFMF) process integrating circulating coagulation, magnetic enhanced flocculation and membrane filtration was investigated for the treatment of surface water micro-polluted by tetracycline, a typical pharmaceutical and personal care product. A bench-scale experiment was conducted and several water quality parameters including turbidity, ultraviolet absorbance at 254 nm (UV254), total organic carbon and tetracycline concentration were evaluated, taking coagulation membrane filtration and magnetic flocculation membrane filtration processes as reference treatments...
July 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/28723846/value-of-fractal-analysis-of-optical-coherence-tomography-angiography-in-various-stages-of-diabetic-retinopathy
#7
Suruchi Bhardwaj, Edmund Tsui, Sarwar Zahid, Emma Young, Nitish Mehta, Steven Agemy, Patricia Garcia, Richard B Rosen, Joshua A Young
PURPOSE: To use fractal dimensional analysis to investigate retinal vascular disease patterns in patients with diabetic retinopathy using spectral domain optical coherence tomography angiography. METHODS: A retrospective study was conducted which included 49 eyes from 26 control subjects and 58 eyes from 35 patients known to have diabetic retinopathy. Of the 58 eyes with known retinopathy, 31 were categorized as nonproliferative diabetic retinopathy (13 mild, 9 moderate, and 9 severe) and 27 were categorized as proliferative diabetic retinopathy...
July 18, 2017: Retina
https://www.readbyqxmd.com/read/28717134/ash-production-by-attrition-in-volcanic-conduits-and-plumes
#8
T J Jones, J K Russell
Tephra deposits result from explosive volcanic eruption and serve as indirect probes into fragmentation processes operating in subsurface volcanic conduits. Primary magmatic fragmentation creates a population of pyroclasts through volatile-driven decompression during conduit ascent. In this study, we explore the role that secondary fragmentation, specifically attrition, has in transforming primary pyroclasts upon transport in volcanic conduits and plumes. We utilize total grain size distributions from a suite of natural and experimentally produced tephra to show that attrition is likely to occur in all explosive volcanic eruptions...
July 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28709260/pneumatic-fractures-in-confined-granular-media
#9
Fredrik K Eriksen, Renaud Toussaint, Antoine L Turquet, Knut J Måløy, Eirik G Flekkøy
We perform experiments where air is injected at a constant overpressure P_{in}, ranging from 5 to 250 kPa, into a dry granular medium confined within a horizontal linear Hele-Shaw cell. The setup allows us to explore compacted configurations by preventing decompaction at the outer boundary, i.e., the cell outlet has a semipermeable filter such that beads are stopped while air can pass. We study the emerging patterns and dynamic growth of channels in the granular media due to fluid flow, by analyzing images captured with a high speed camera (1000 images/s)...
June 2017: Physical Review. E
https://www.readbyqxmd.com/read/28709196/characterizing-time-series-via-complexity-entropy-curves
#10
Haroldo V Ribeiro, Max Jauregui, Luciano Zunino, Ervin K Lenzi
The search for patterns in time series is a very common task when dealing with complex systems. This is usually accomplished by employing a complexity measure such as entropies and fractal dimensions. However, such measures usually only capture a single aspect of the system dynamics. Here, we propose a family of complexity measures for time series based on a generalization of the complexity-entropy causality plane. By replacing the Shannon entropy by a monoparametric entropy (Tsallis q entropy) and after considering the proper generalization of the statistical complexity (q complexity), we build up a parametric curve (the q-complexity-entropy curve) that is used for characterizing and classifying time series...
June 2017: Physical Review. E
https://www.readbyqxmd.com/read/28707523/strut-analyses-for-detecting-osteoporosis-using-dental-panoramic-radiography
#11
Jae Joon Hwang, Jeong-Hee Lee, Young Hyun Kim, Ho-Gul Jeong, Yoon Jeong Choi, Wonse Park, Sang-Sun Han
OBJECTIVES: The aim of this study was to identify variables that can be used for osteoporosis detection using strut analysis, fractal dimension (FD), and the gray level co-occurrence matrix (GLCM) using multiple regions of interest (ROIs) and to develop an osteoporosis detection model based on panoramic radiography. METHODS: A total of 454 panoramic radiographs from oral examinations in our dental hospital from 2012 to 2015 were randomly selected, equally distributed among osteoporotic and non-osteoporotic patients (n=227 in each group)...
July 14, 2017: Dento Maxillo Facial Radiology
https://www.readbyqxmd.com/read/28704515/structural-characterization-of-chaos-game-fractals-using-small-angle-scattering-analysis
#12
Eugen Mircea Anitas, Azat Slyamov
Small-angle scattering (SAS) technique is applied to study the nano and microstructural properties of spatial patterns generated from chaos game representation (CGR). Using a simplified version of Debye formula, we calculate and analyze in momentum space, the monodisperse scattering structure factor from a system of randomly oriented and non-interacting 2D Sierpinski gaskets (SG). We show that within CGR approach, the main geometrical and fractal properties, such as the overall size, scaling factor, minimal distance between scattering units, fractal dimension and the number of units composing the SG, can be recovered...
2017: PloS One
https://www.readbyqxmd.com/read/28691721/nonlinear-dynamics-analysis-of-the-human-balance-control-subjected-to-physical-and-sensory-perturbations
#13
Mohammed N Ashtiani, Azghani Mahmood-Reza
Postural control after applying perturbation involves neural and muscular efforts to limit the center of mass (CoM) motion. Linear dynamical approaches may not unveil all complexities of body efforts. This study was aimed at determining two nonlinear dynamics parameters (fractal dimension (FD) and largest Lyapunov exponent (LLE)) in addition to the linear standing metrics of balance in perturbed stance. Sixteen healthy young males were subjected to sudden rotations of the standing platform. The vision and cognition during the standing were also interfered...
2017: Acta Neurobiologiae Experimentalis
https://www.readbyqxmd.com/read/28684850/the-role-of-city-size-and-urban-form-in-the-surface-urban-heat-island
#14
Bin Zhou, Diego Rybski, Jürgen P Kropp
Urban climate is determined by a variety of factors, whose knowledge can help to attenuate heat stress in the context of ongoing urbanization and climate change. We study the influence of city size and urban form on the Urban Heat Island (UHI) phenomenon in Europe and find a complex interplay between UHI intensity and city size, fractality, and anisometry. Due to correlations among these urban factors, interactions in the multi-linear regression need to be taken into account. We find that among the largest 5,000 cities, the UHI intensity increases with the logarithm of the city size and with the fractal dimension, but decreases with the logarithm of the anisometry...
July 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28679066/agro-waste-biosorbents-effect-of-physico-chemical-properties-on-atrazine-and-imidacloprid-sorption
#15
Abhishek Mandal, Neera Singh, Lata Nain
Low cost agro-waste biosorbents namely eucalyptus bark (EB), corn cob (CC), bamboo chips (BC), rice straw (RS) and rice husk (RH) were characterized and used to study atrazine and imidacloprid sorption. Adsorption studies suggested that biosorbents greatly varied in their pesticide sorption behaviour. The EB was the best biosorbent to sorb both atrazine and imidacloprid with KF values of 169.9 and 85.71, respectively. The adsorption isotherm were nonlinear in nature with slope (1/n) values <1. The Freundlich constant Correlating atrazine/imidacloprid sorption parameter [KF...
July 5, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/28671629/motor-imagery-eeg-classification-for-patients-with-amyotrophic-lateral-sclerosis-using-fractal-dimension-and-fisher-s-criterion-based-channel-selection
#16
Yi-Hung Liu, Shiuan Huang, Yi-De Huang
Motor imagery is based on the volitional modulation of sensorimotor rhythms (SMRs); however, the sensorimotor processes in patients with amyotrophic lateral sclerosis (ALS) are impaired, leading to degenerated motor imagery ability. Thus, motor imagery classification in ALS patients has been considered challenging in the brain-computer interface (BCI) community. In this study, we address this critical issue by introducing the Grassberger-Procaccia and Higuchi's methods to estimate the fractal dimensions (GPFD and HFD, respectively) of the electroencephalography (EEG) signals from ALS patients...
July 3, 2017: Sensors
https://www.readbyqxmd.com/read/28666911/geometrical-complexity-of-cortical-microvascularization-in-moyamoya-disease
#17
Katsuya Komatsu, Takeshi Mikami, Hime Suzuki, Yukinori Akiyama, Rei Enatsu, Masahiko Wanibuchi, Nobuhiro Mikuni
BACKGROUND: Dilatation of the microvascular diameter is recognized in moyamoya disease, and referred to as microvascularization. The purpose of this study is to characterize the cortical microvascularization in moyamoya disease using imaging analysis, and to discuss the developmental mechanism of the collateral network around the cortical surface. METHODS: A total of 20 hemispheric sides of 14 patients with moyamoya disease were included in this study. From the intraoperative images, cortical surface images were extracted, and binary images were subsequently created...
June 27, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28642460/standing-wave-effect-and-fractal-structure-in-dislocation-evolution
#18
P Li, Z F Zhang
Theoretical model required for the evolution of regular dislocation pattern should simultaneously take into account both static distribution and dynamic evolution of dislocation pattern. In principle, there exists a stable uniformly moving dislocation with both core and far field advancing at the same constant velocity, which suggests the existence of the traveling waves representing moving dislocation. Therefore, one new term "dislocation wave" is defined by simultaneously consisting of both an elastic wave and a dislocation in each wavefront...
June 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28635291/fractal-model-for-wettability-of-rough-surfaces
#19
R Jain, R Pitchumani
This paper presents a fractal model to describe wettability on multiscale randomly rough surfaces. Hydrophobic or superhydrophobic surfaces, produced by processes such as electrodeposition and etching, lead to the creation of random roughness at multiple length scales on the surface. This paper considers the description of such surfaces with a fractal asperity model based on the Weierstrass-Mandelbrot (W-M) function, where the fractal parameters are uniquely determined from a power spectrum of the surface. By use of this description, a model is presented to evaluate the apparent contact angle in the different wetting regimes...
July 6, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28633840/changes-in-pore-size-distribution-inside-sludge-under-various-ultrasonic-conditions
#20
Fang Zhao, Daolai Cheng
The pore size distribution is quite significant for determining the transport capacity of heat and moisture in sludge during the drying process. It is crucial to investigate the transformation of the pore size in sludge under sonication. In this paper, the microstructures of pores inside sludge before and after ultrasonic treatment with various ultrasonic conditions were observed using a microscope. Fractal geometry and image analysis were combined to quantitatively identify the evolution of pore size in sludge undergoing various acoustic energy densities and treatment times...
September 2017: Ultrasonics Sonochemistry
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