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https://www.readbyqxmd.com/read/28334026/exploring-the-link-between-multiscale-entropy-and-fractal-scaling-behavior-in-near-surface-wind
#1
Miguel Nogueira
The equivalency between the power law behavior of Multiscale Entropy (MSE) and of power spectra opens a promising path for interpretation of complex time-series, which is explored here for the first time for atmospheric fields. Additionally, the present manuscript represents a new independent empirical validation of such relationship, the first one for the atmosphere. The MSE-fractal relationship is verified for synthetic fractal time-series covering the full range of exponents typically observed in the atmosphere...
2017: PloS One
https://www.readbyqxmd.com/read/28331228/traumatic-brain-injury-results-in-acute-rarefication-of-the-vascular-network
#2
Andre Obenaus, Michelle Ng, Amanda M Orantes, Eli Kinney-Lang, Faisal Rashid, Mary Hamer, Richard A DeFazio, Jiping Tang, John H Zhang, William J Pearce
The role of the cerebrovascular network and its acute response to TBI is poorly defined and emerging evidence suggests that cerebrovascular reactivity is altered. We explored how cortical vessels are physically altered following TBI using a newly developed technique, vessel painting. We tested our hypothesis that a focal moderate TBI results in global decrements to structural aspects of the vasculature. Rats (naïve, sham-operated, TBI) underwent a moderate controlled cortical impact. Animals underwent vessel painting perfusion to label the entire cortex at 1 day post TBI followed by whole brain axial and coronal images using a wide-field fluorescence microscope...
March 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28330876/electrocorticographic-dynamics-as-a-novel-biomarker-in-five-models-of-epileptogenesis
#3
Dan Z Milikovsky, Itai Weissberg, Lyna Solomon-Kamintsky, Kristina Lippmann, Osnat Schefenbauer, Federica Frigerio, Massimo Rizzi, Liron Sheintuch, Daniel Zelig, Jonathan Ofer, Annamaria Vezzani, Alon Friedman
Post injury epilepsy (PIE) is a devastating sequela of various brain insults. While recent studies offer novel insights into the mechanisms underlying epileptogenesis and discover potential preventive treatments, the lack of PIE biomarkers hinders the clinical implementation of such treatments. Here we explored the biomarker potential of different electrographic features in five models of PIE. Electrocorticographic or intrahippocampal recordings of epileptogenesis (from the insult to the first spontaneous seizure) from two laboratories were analyzed in 3 mouse and 2 rat PIE models...
March 22, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28327698/accuracy-and-reliability-of-different-cone-beam-computed-tomography-cbct-devices-for-structural-analysis-of-alveolar-bone-in-comparison-with-multislice-ct-and-micro-ct
#4
Jeroen Van Dessel, Laura Ferreira Pinheiro Nicolielo, Yan Huang, Walter Coudyzer, Benjamin Salmon, Ivo Lambrichts, Reinhilde Jacobs
OBJECTIVE: The aim of this study was to assess whether cone beam computed tomography (CBCT) may be used for clinically reliable alveolar bone quality assessment in comparison to its clinical alternatives, multislice computed tomography and the gold standard (micro-CT). MATERIALS AND METHODS: Six dentate mandibular bone samples were scanned with seven CBCT devices (ProMax 3D Max, NewTom GiANO, Cranex 3D, 3D Accuitomo 170, Carestream 9300, Scanora 3D, I-CAT Next generation), one micro-CT scanner (SkyScan 1174) and one MSCT machine (Somatom Definition Flash) using two protocols (standard and high-resolution)...
2017: European Journal of Oral Implantology
https://www.readbyqxmd.com/read/28327562/transition-of-temporal-scaling-behavior-in-percolation-assisted-shear-branching-structure-during-plastic-deformation
#5
Jingli Ren, Cun Chen, Gang Wang, Peter K Liaw
This paper explores the temporal scaling behavior induced shear-branching structure in response to variant temperatures and strain rates during plastic deformation of Zr-based bulk metallic glass (BMG). The data analysis based on the compression tests suggests that there are two states of shear-branching structures: the fractal structure with a long-range order at an intermediate temperature of 223 K and a larger strain rate of 2.5 × 10(-2) s(-1); the disordered structure dominated at other temperature and strain rate...
March 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28326028/inter-trial-correlations-in-predictive-saccade-endpoints-fractal-scaling-reflects-differential-control-along-task-relevant-and-orthogonal-directions
#6
Pamela Federighi, Aaron L Wong, Mark Shelhamer
Saccades exhibit variation in performance from one trial to the next, even when paced at a constant rate by targets at two fixed locations. We previously showed that amplitude fluctuations in consecutive predictive saccades have fractal structure: the spectrum of the sequence of consecutive amplitudes has a power-law (f(-α)) form, indicative of inter-trial correlations that reflect the storage of prior performance information to guide the planning of subsequent movements. More gradual decay of these inter-trial correlations coincides with a larger magnitude of spectral slope α, and indicates stronger information storage over longer times...
2017: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/28325224/number-of-succussion-strokes-affects-effectiveness-of-ultra-high-diluted-arsenic-on-in%C3%A2-vitro-wheat-germination-and-polycrystalline-structures-obtained-by-droplet-evaporation-method
#7
Lucietta Betti, Grazia Trebbi, Maria Olga Kokornaczyk, Daniele Nani, Maurizio Peruzzi, Giovanni Dinelli, Paolo Bellavite, Maurizio Brizzi
OBJECTIVES: The aim of this study is to investigate whether the number of succussion strokes applied after each dilution step when preparing the homeopathic treatments influences the effectiveness of ultra-high-diluted (UHD) arsenic trioxide at the 45th decimal dilution/dynamization (As2O3 45x). DESIGN: Wheat seeds, previously stressed with ponderal As2O3, were treated with: As2O3 45x, H2O 45x (dynamized control), or pure water (negative control). The succussion was done manually, and various succussion durations (numbers of strokes) were tested for each treatment...
February 2017: Homeopathy: the Journal of the Faculty of Homeopathy
https://www.readbyqxmd.com/read/28324991/features-of-cerebral-oxygenation-detects-brain-injury-in-premature-infants
#8
John M O'Toole, Mmoloki Kenosi, Daragh Finn, Geraldine B Boylan, Eugene M Dempsey
Babies born prematurely can develop brain injury within days after birth. Early identification of high-risk infants enables appropriate clinical care to mitigate potential lifelong disabilities. Near infra-red spectroscopy is an established technology that can provide continuous measurements of cerebral oxygen saturation (rcSO2) over this critical period. We develop a feature set of the rcSO2 signal for the purpose of detecting brain injury. Our feature set contains amplitude, spectral, and fractal dimension features within 5 frequency bands...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324693/cortical-complexity-in-bipolar-disorder-applying-a-spherical-harmonics-approach
#9
Igor Nenadic, Rachel A Yotter, Maren Dietzek, Kerstin Langbein, Heinrich Sauer, Christian Gaser
Recent studies using surface-based morphometry of structural magnetic resonance imaging data have suggested that some changes in bipolar disorder (BP) might be neurodevelopmental in origin. We applied a novel analysis of cortical complexity based on fractal dimensions in high-resolution structural MRI scans of 18 bipolar disorder patients and 26 healthy controls. Our region-of-interest based analysis revealed increases in fractal dimensions (in patients relative to controls) in left lateral orbitofrontal cortex and right precuneus, and decreases in right caudal middle frontal, entorhinal cortex, and right pars orbitalis, and left fusiform and posterior cingulate cortices...
February 21, 2017: Psychiatry Research
https://www.readbyqxmd.com/read/28323871/power-considerations-for-the-application-of-detrended-fluctuation-analysis-in-gait-variability-studies
#10
Nikita A Kuznetsov, Christopher K Rhea
The assessment of gait variability using stochastic signal processing techniques such as detrended fluctuation analysis (DFA) has been shown to be a sensitive tool for evaluation of gait alterations due to aging and neuromuscular disease. However, previous studies have suggested that the application of DFA requires relatively long recordings (600 strides), which is difficult when working with clinical populations or older adults. In this paper we propose a model for predicting DFA variance in experimental data and conduct a Monte Carlo simulation to estimate the sample size and number of trials required to detect a change in DFA scaling exponent...
2017: PloS One
https://www.readbyqxmd.com/read/28323684/shifting-spatial-neglect-with-repeated-line-bisections-possible-role-of-lateralized-attentional-fatigue
#11
Mary Woods, John B Williamson, Keith D White, Charles G Maitland, Kenneth M Heilman
BACKGROUND AND OBJECTIVE: Many patients who have signs of neglect immediately after a right hemisphere stroke remain disabled even when they improve on tests of neglect. Few patients are tested for attentional persistence and fatigue despite their importance in many instrumental activities. To investigate whether stimulus repetition might alter the allocation of attention, we repeatedly tested a patient 16 weeks after she developed hemispatial neglect from a right hemisphere stroke. METHODS: During each of three testing sessions given in 1 day, we asked the patient to bisect 90 lines of two lengths, presented in 30-trial blocks in three locations: left, center, and right of her midsagittal plane, partially counterbalanced across sessions...
March 2017: Cognitive and Behavioral Neurology: Official Journal of the Society for Behavioral and Cognitive Neurology
https://www.readbyqxmd.com/read/28322332/a-global-reference-model-of-curie-point-depths-based-on-emag2
#12
Chun-Feng Li, Yu Lu, Jian Wang
In this paper, we use a robust inversion algorithm, which we have tested in many regional studies, to obtain the first global model of Curie-point depth (GCDM) from magnetic anomaly inversion based on fractal magnetization. Statistically, the oceanic Curie depth mean is smaller than the continental one, but continental Curie depths are almost bimodal, showing shallow Curie points in some old cratons. Oceanic Curie depths show modifications by hydrothermal circulations in young oceanic lithosphere and thermal perturbations in old oceanic lithosphere...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28319768/quantitative-evaluation-of-the-interfacial-interactions-between-a-randomly-rough-sludge-floc-and-membrane-surface-in-a-membrane-bioreactor-based-on-fractal-geometry
#13
Meijia Zhang, Xiaoling Zhou, Liguo Shen, Xiang Cai, Fangyuan Wang, Jianrong Chen, Hongjun Lin, Renjie Li, Xilin Wu, Bao-Qiang Liao
In this paper, a new method for quantification of interfacial interactions between a randomly rough particle and membrane surface was proposed. It was found that sludge flocs in a membrane bioreactor were of apparent fractal characteristics, and could be modeled by the modified two-variable Weierstrass-Mandelbrot (WM) function. By combining the surface element integration (SEI) method, differential geometry and composite Simpson's rule, the quantitation method for calculating such interfacial interactions was further developed...
March 8, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28318637/impact-of-multiple-en-face-image-averaging-on-quantitative-assessment-from-optical-coherence-tomography-angiography-images
#14
Akihito Uji, Siva Balasubramanian, Jianqin Lei, Elmira Baghdasaryan, Mayss Al-Sheikh, SriniVas R Sadda
PURPOSE: To investigate the impact of multiple en face image averaging on quantitative measurements of the retinal microvasculature using optical coherence tomography angiography (OCTA). DESIGN: Prospective, observational, cross-sectional case series. PARTICIPANTS: Twenty-one healthy individuals with normal eyes. METHODS: Macular OCTA images were acquired from all participants using the Zeiss Cirrus 5000 with Angioplex OCTA software (Carl Zeiss Meditec, Dublin, CA)...
March 16, 2017: Ophthalmology
https://www.readbyqxmd.com/read/28306131/electrocortical-spectral-analysis-and-fractal-methods-for-assessing-the-effects-of-unilateral-brain-injury-on-rat-cerebellum
#15
L D Martac, S Sekulic, M Cvijanovic
We used electrocortical spectral analysis and fractal methods for assessing the effects of unilateral, single brain injury on cerebellum. Cerebellar electrocortical activity was recorded in control state (before the injury) and after a single brain injury of the cerebellar cortex in anesthetized rats. We noticed that the mean power in gamma high-frequency domain (32-128 Hz) of the cerebellum, was increased after the first brain injury, while after a two-week recovery, it was larger than before the injury. The unilateral brain injury induced a permanent increase of the mild gamma activity in both the left and the right side of cerebellum cortex, but there was no further increase after the lesion was repeated...
December 1, 2016: Archives Italiennes de Biologie
https://www.readbyqxmd.com/read/28304066/marginally-compact-hyperbranched-polymer-trees
#16
M Dolgushev, J P Wittmer, A Johner, O Benzerara, H Meyer, J Baschnagel
Assuming Gaussian chain statistics along the chain contour, we generate by means of a proper fractal generator hyperbranched polymer trees which are marginally compact. Static and dynamical properties, such as the radial intrachain pair density distribution ρpair(r) or the shear-stress relaxation modulus G(t), are investigated theoretically and by means of computer simulations. We emphasize that albeit the self-contact density diverges logarithmically with the total mass N, this effect becomes rapidly irrelevant with increasing spacer length S...
March 17, 2017: Soft Matter
https://www.readbyqxmd.com/read/28301524/fractal-features-of-soil-particle-size-distribution-under-different-land-use-patterns-in-the-alluvial-fans-of-collapsing-gullies-in-the-hilly-granitic-region-of-southern-china
#17
Yusong Deng, Chongfa Cai, Dong Xia, Shuwen Ding, Jiazhou Chen
Collapsing gullies are among the most severe soil erosion problems in the tropical and subtropical areas of southern China. However, few studies have examined the relationship of soil particle size distribution (PSD) changes with land-use patterns in the alluvial fans of collapsing gullies. Recently, the fractal method has been applied to estimate soil structure and has proven to be an effective tool in analyzing soil properties and their relationships with other eco-environmental factors. In this study, the soil fractal dimension (D), physico-chemical properties and their relationship with different land-use patterns in alluvial fans were investigated in an experiment that involved seven collapsing gully areas in seven counties of southern China...
2017: PloS One
https://www.readbyqxmd.com/read/28297948/fractally-fourier-decimated-homogeneous-turbulent-shear-flow-in-noninteger-dimensions
#18
Mani Fathali, Saber Khoei
Time evolution of the fully resolved incompressible homogeneous turbulent shear flow in noninteger Fourier dimensions is numerically investigated. The Fourier dimension of the flow field is extended from the integer value 3 to the noninteger values by projecting the Navier-Stokes equation on the fractal set of the active Fourier modes with dimensions 2.7≤d≤3.0. The results of this study revealed that the dynamics of both large and small scale structures are nontrivially influenced by changing the Fourier dimension d...
February 2017: Physical Review. E
https://www.readbyqxmd.com/read/28297904/scale-dependent-colocalization-in-a-population-of-gyrotactic-swimmers
#19
M Borgnino, F De Lillo, G Boffetta
We study the small scale clustering of gyrotactic swimmers transported by a turbulent flow, when the intrinsic variability of the swimming parameters within the population is considered. By means of extensive numerical simulations, we find that the variety of the population introduces a characteristic scale R^{*} in its spatial distribution. At scales smaller than R^{*} the swimmers are homogeneously distributed, while at larger scales an inhomogeneous distribution is observed with a fractal dimension close to what observed for a monodisperse population characterized by mean parameters...
February 2017: Physical Review. E
https://www.readbyqxmd.com/read/28297879/packing-loops-into-annular-cavities
#20
T A Sobral, M A F Gomes
The continuous packing of a flexible rod in two-dimensional cavities yields a countable set of interacting domains that resembles nonequilibrium cellular systems and belongs to a new class of lightweight material. However, the link between the length of the rod and the number of domains requires investigation, especially in the case of non-simply connected cavities, where the number of avoided regions emulates an effective topological temperature. In the present article we report the results of an experiment of injection of a single flexible rod into annular cavities in order to find the total length needed to insert a given number of loops (domains of one vertex)...
February 2017: Physical Review. E
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