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https://www.readbyqxmd.com/read/28107414/multifractality-and-network-analysis-of-phase-transition
#1
Longfeng Zhao, Wei Li, Chunbin Yang, Jihui Han, Zhu Su, Yijiang Zou
Many models and real complex systems possess critical thresholds at which the systems shift dramatically from one sate to another. The discovery of early-warnings in the vicinity of critical points are of great importance to estimate how far the systems are away from the critical states. Multifractal Detrended Fluctuation analysis (MF-DFA) and visibility graph method have been employed to investigate the multifractal and geometrical properties of the magnetization time series of the two-dimensional Ising model...
2017: PloS One
https://www.readbyqxmd.com/read/28107389/effect-of-axial-eye-length-on-retinal-vessel-parameters-in-6-to-12-year-old-malay-girls
#2
Evelyn Li Min Tai, Ling-Jun Li, Wan Hitam Wan-Hazabbah, Tien-Yin Wong, Ismail Shatriah
PURPOSE: Retinal vessel analysis is affected by both systemic and ocular factors. Malays are the major ethnicity in South East Asia. Data on the retinal microvasculature in Malays is limited, especially among children. We aim to evaluate the influence of ocular biometry on retinal vessel parameters in young Malay girls. METHODS: This was a cross-sectional, hospital-based study involving 86 Malay girls aged 6 to 12 years old in Hospital Universiti Sains Malaysia from 2015-2016...
2017: PloS One
https://www.readbyqxmd.com/read/28106222/digestibility-and-supramolecular-structural-changes-of-maize-starch-by-non-covalent-interactions-with-gallic-acid
#3
Chengdeng Chi, Xiaoxi Li, Yiping Zhang, Ling Chen, Lin Li, Zhijiang Wang
The effects of non-covalent interactions between gallic acid (GA) and starch on starch digestibility and supramolecular structural changes (short-range ordered molecular structure, crystalline structure, lamellar structure and fractal structure) were investigated. The results indicated that the digestibility of both starches was substantially reduced in the rapidly digestible starch (RDS) content, but resistant starch (RS) was increased after interacting with GA. The RS content of starch-GA complexes ranged from 17...
January 20, 2017: Food & Function
https://www.readbyqxmd.com/read/28106087/dynamical-states-possibilities-and-propagation-of-stress-signal
#4
Md Zubbair Malik, Shahnawaz Ali, Soibam Shyamchand Singh, Romana Ishrat, R K Brojen Singh
The stress driven dynamics of Notch-Wnt-p53 cross-talk is subjected to a few possible dynamical states governed by simple fractal rules, and allowed to decide its own fate by choosing one of these states which are contributed from long range correlation with varied fluctuations due to active molecular interaction. The topological properties of the networks corresponding to these dynamical states have hierarchical features with assortive structure. The stress signal driven by nutlin and modulated by mediator GSK3 acts as anti-apoptotic signal in this system, whereas, the stress signal driven by Axin and modulated by GSK3 behaves as anti-apoptotic for a certain range of Axin and GSK3 interaction, and beyond which the signal acts as favor-apoptotic signal...
January 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28105407/campanula-lingulata-populations-on-mt-olympus-greece-where-s-the-abundant-centre
#5
Anastasia E Tzortzaki, Despoina Vokou, John M Halley
BACKGROUND: The abundant-centre hypothesis (ACH) assumes that a species becomes more abundant at the centre of its range, where the environmental conditions are most favorable. As we move away from this centre, abundance and occupancy decline. Although this is obvious intuitively, efforts to confirm the hypothesis have often failed. We investigated the abundance patterns of Campanula lingulata across its altitudinal range on Mt. Olympus, Greece, in order to evaluate the "abundant centre" hypothesis along an elevation gradient...
December 2017: Journal of Biological Research
https://www.readbyqxmd.com/read/28103526/cognitive-representation-of-musical-fractals-processing-hierarchy-and-recursion-in-the-auditory-domain
#6
Mauricio Dias Martins, Bruno Gingras, Estela Puig-Waldmueller, W Tecumseh Fitch
The human ability to process hierarchical structures has been a longstanding research topic. However, the nature of the cognitive machinery underlying this faculty remains controversial. Recursion, the ability to embed structures within structures of the same kind, has been proposed as a key component of our ability to parse and generate complex hierarchies. Here, we investigated the cognitive representation of both recursive and iterative processes in the auditory domain. The experiment used a two-alternative forced-choice paradigm: participants were exposed to three-step processes in which pure-tone sequences were built either through recursive or iterative processes, and had to choose the correct completion...
January 16, 2017: Cognition
https://www.readbyqxmd.com/read/28102955/compound-speckle-model-detects-anti-angiogenic-tumor-response-in-preclinical-nonlinear-contrast-enhanced-ultrasonography
#7
Matthew R Lowerison, Justin J Tse, M Nicole Hague, Ann F Chambers, David W Holdsworth, James C Lacefield
PURPOSE: This paper proposes a method for analyzing the first-order speckle statistics of nonlinear contrast-enhanced ultrasound images from tumors. METHODS: Contrast signal intensity is modeled as a compound distribution of exponential probability density functions with a gamma weighting function. The gamma probability weighting function serves as an approximation for log-normally distributed flow velocities in a vascular network. The model was applied to sub-harmonic bolus-injection images acquired from a mouse breast cancer xenograft model treated with murine version bevacizumab...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28100181/gestational-diabetes-mellitus-and-retinal-microvasculature
#8
Ling-Jun Li, Michael Kramer, Robyn J Tapp, Ryan E K Man, Ngee Lek, Shirong Cai, Fabian Yap, Peter Gluckman, Kok Hian Tan, Yap Seng Chong, Jia Yu Koh, Seang Mei Saw, Yin Bun Cheung, Tien Yin Wong
BACKGROUND: Small-vessel dysfunction may be an important consequence of chronic hyperglycemia. We examined the association between gestational diabetes mellitus (GDM), a state of transient hyperglycemia during pregnancy, and retinal microvascular changes in pregnant women at 26-28 weeks of pregnancy. METHODS: A total of 1136 pregnant women with singleton pregnancies were recruited during their first trimester at two major Singapore maternity hospitals in an on-going birth cohort study...
January 18, 2017: BMC Ophthalmology
https://www.readbyqxmd.com/read/28094311/evidence-of-microvascular-changes-in-the-retina-following-kawasaki-disease
#9
Katherine Y H Chen, David P Burgner, Tien Y Wong, Seang Mei Saw, Swee Chye Quek, Audrey Y C Pang, Seo Wei Leo, Inez B Wong, Diana Zannino, Nigel Curtis, Michael Cheung, Carol Y Cheung, Terence C W Lim
It is unclear whether all children with Kawasaki disease (KD) have increased later cardiovascular risk. The retinal microvasculature reflects changes in the microcirculation and is associated with traditional cardiovascular risk factors and events. The aim of this study was to investigate retinal microvascular parameters in two populations of patients with previous KD and control participants. We performed case-control studies of 116 (57 patients and 59 control participants) Australian and 156 (78 patients and 78 control participants) Singaporean individuals, at least two years since their acute illness...
January 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28092955/flow-optimization-in-vascular-networks
#10
Radu C Cascaval, Ciro D'Apice, Maria Pia D'Arienzo, Rosanna Manzo
The development of mathematical models for studying phenomena observed in vascular networks is very useful for its potential applications in medicine and physiology. Detailed 3D studies of flow in the arterial system based on the Navier-Stokes equations require high computational power, hence reduced models are often used, both for the constitutive laws and the spatial domain. In order to capture the major features of the phenomena under study, such as variations in arterial pressure and flow velocity, the resulting PDE models on networks require appropriate junction and boundary conditions...
June 1, 2017: Mathematical Biosciences and Engineering: MBE
https://www.readbyqxmd.com/read/28088542/interaction-of-earthworms-microbe-facilitating-biofilm-dewaterability-performance-during-wasted-activated-sludge-reduction-and-stabilization
#11
Yadan Zheng, Meiyan Xing, Luziyu Cai, Tao Xiao, Yufan Lu, Jinzhou Jiang
Sludge dewaterability was chemically and morphologically explored during sewage sludge treatment by vermifiltration. The results, with a conventional biofilter (BF, no earthworms) as a control, demonstrated that the capillary suction time(CST) and specific resistance of filtration(SRF) of vermifilter (VF, with earthworms) treated sludge were 64.9±1.7s and (23.1±1.3)×10(12)m/kg,16.8% and 36.0% lower than that of the BF, respectively. Additionally, the VF could efficiently decompose loosely bound extracellular polymeric substances (LB-EPS), releasing more water trapped inside biofilm...
January 11, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28079383/structure-and-interaction-in-ph-dependent-phase-behavior-of-nanoparticle-protein-systems
#12
Indresh Yadav, Sugam Kumar, Vinod K Aswal, Joachim Kohlbrecher
The pH-dependent structure and interaction of anionic silica nanoparticles (diameter 18 nm) with two globular model proteins-lysozyme and bovine serum albumin (BSA) have been studied. Cationic lysozyme adsorbs strongly on the nanoparticles and the adsorption follows an exponential growth as a function of lysozyme concentration, where the saturation value increases with pH approaching towards the isoelectric point (IEP) of lysozyme. In contrast, irrespective of the pH, anionic BSA does not show any adsorption...
January 12, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28079249/fractal-analysis-of-visual-search-activity-for-mass-detection-during-mammographic-screening
#13
Folami Alamudun, Hong-Jun Yoon, Kathleen B Hudson, Garnetta Morin-Ducote, Tracy Hammond, Georgia D Tourassi
PURPOSE: The objective of this study is to assess the complexity of human visual search activity during mammographic screening using fractal analysis and to investigate its relationship with case and reader characteristics. METHODS: The study was performed for the task of mammographic screening with simultaneous viewing of four coordinated breast views as typically done in clinical practice. Eye-tracking data and diagnostic decisions collected for 100 mammographic cases (25 normal, 25 benign, 50 malignant) and 10 readers (three board certified radiologists and seven radiology residents), formed the corpus data for this study...
January 12, 2017: Medical Physics
https://www.readbyqxmd.com/read/28075432/aggregation-and-deposition-of-in-situ-formed-colloidal-particles-in-the-presence-of-polyelectrolytes
#14
Feng Li, Dejun Sun, Tao Wu, Yujiang Li
In this work, aggregation and deposition of in situ formed magnesium hydroxide (IFM) in the presence of hydrolyzed polyacrylamide (HPAM) were investigated. Relative concentrations of interactants, as well as other experimental conditions, were changed to elucidate the interaction mechanisms from microscopic to macroscopic levels. Light scattering measurements were used to investigate the aggregation kinetics, fractal dimension, and collision efficiency of the aggregates on a microscopic level. Electrophoretic mobility and TEM were utilized to measure the charging properties and morphologies of aggregates, respectively...
January 11, 2017: Soft Matter
https://www.readbyqxmd.com/read/28072842/fractal-analysis-of-brain-blood-oxygenation-level-dependent-bold-signals-from-children-with-mild-traumatic-brain-injury-mtbi
#15
Olga Dona, Michael D Noseworthy, Carol DeMatteo, John F Connolly
BACKGROUND: Conventional imaging techniques are unable to detect abnormalities in the brain following mild traumatic brain injury (mTBI). Yet patients with mTBI typically show delayed response on neuropsychological evaluation. Because fractal geometry represents complexity, we explored its utility in measuring temporal fluctuations of brain resting state blood oxygen level dependent (rs-BOLD) signal. We hypothesized that there could be a detectable difference in rs-BOLD signal complexity between healthy subjects and mTBI patients based on previous studies that associated reduction in signal complexity with disease...
2017: PloS One
https://www.readbyqxmd.com/read/28067200/quantitative-angiography-methods-for-bifurcation-lesions-a-consensus-statement-update-from-the-european-bifurcation-group
#16
Carlos Collet, Yoshinobu Onuma, Rafael Cavalcante, Maik Grundeken, Philippe Généreux, Jeffrey Popma, Ricardo Costa, Goran Stankovic, Shengxian Tu, Johan H C Reiber, Jean-Paul Aben, Jens Flensted Lassen, Yves Louvard, Alexandra Lansky, Patrick W Serruys
Bifurcation lesions represent one of the most challenging lesions subset in interventional cardiology. The European Bifurcation Club (EBC) is an academic consortium whose goal has been to assess and recommend the appropriate strategies to manage bifurcation lesions. The quantitative coronary angiography (QCA) methods for the evaluation of bifurcation lesions has been subject to extensive research. Single vessel quantitative coronary angiography (QCA) has shown to be inaccurate to assess bifurcation lesions dimensions...
January 10, 2017: EuroIntervention
https://www.readbyqxmd.com/read/28063435/local-structure-of-percolating-gels-at-very-low-volume-fractions
#17
Samuel Griffiths, Francesco Turci, C Patrick Royall
The formation of colloidal gels is strongly dependent on the volume fraction of the system and the strength of the interactions between the colloids. Here we explore very dilute solutions by the means of numerical simulations and show that, in the absence of hydrodynamic interactions and for sufficiently strong interactions, percolating colloidal gels can be realised at very low values of the volume fraction. Characterising the structure of the network of the arrested material we find that, when reducing the volume fraction, the gels are dominated by low-energy local structures, analogous to the isolated clusters of the interaction potential...
January 7, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28059537/universal-formula-for-the-mean-first-passage-time-in-planar-domains
#18
Denis S Grebenkov
We derive a general exact formula for the mean first passage time (MFPT) from a fixed point inside a planar domain to an escape region on its boundary. The underlying mixed Dirichlet-Neumann boundary value problem is conformally mapped onto the unit disk, solved exactly, and mapped back. The resulting formula for the MFPT is valid for an arbitrary space-dependent diffusion coefficient, while the leading logarithmic term is explicit, simple, and remarkably universal. In contrast to earlier works, we show that the natural small parameter of the problem is the harmonic measure of the escape region, not its perimeter...
December 23, 2016: Physical Review Letters
https://www.readbyqxmd.com/read/28059426/the-effect-of-colloidal-aggregates-on-fat-crystal-networks
#19
Raamanand R Chauhan, Roel P A Dullens, Krassimir P Velikov, Dirk G A L Aarts
We investigate the role of a colloidal model system in the crystallization and network formation of lipids. This system consists of fractal fumed silica aggregates. We look at the influence of different solid fat concentrations and fumed silica concentrations on the resulting gel network. Oscillatory rheology shows that the addition of silica to fat-in-oil gels does not significantly affect the magnitude of the storage modulus within the linear viscoelastic region. Interestingly, the range of this region is increased...
January 6, 2017: Food & Function
https://www.readbyqxmd.com/read/28058083/simulating-the-hydrodynamics-of-self-propelled-colloidal-clusters-using-stokesian-dynamics
#20
Yousef M F El Hasadi, Martin Crapper
Self-propelled clusters are involved in many technological applications such as in material science and biotechnology, and understanding their interaction with the fluid that surrounds them is of a great importance. We present results of swimming velocity and energy dissipation obtained through Stokesian dynamics simulations of self-propelled clusters. The clusters are of diffusion limited aggregates, consisting of force- and torque-free spherical particles. The number of particles per cluster ranges from 100 to 400, and with two fractal dimensions of 2...
November 2016: Biomicrofluidics
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