Read by QxMD icon Read

sample entropy

Irene Vrbik, Samantha J Van Nest, Phiranuphon Meksiarun, Jason Loeppky, Alexandre Brolo, Julian J Lum, Andrew Jirasek
Tumour heterogeneity plays a large role in the response of tumour tissues to radiation therapy. Inherent biological, physical, and even dose deposition heterogeneity all play a role in the resultant observed response. We here implement the use of Haralick textural analysis to quantify the observed glycogen production response, as observed via Raman spectroscopic mapping, of tumours irradiated within a murine model. While an array of over 20 Haralick features have been proposed, we here concentrate on five of the most prominent features: homogeneity, local homogeneity, contrast, entropy, and correlation...
2019: PloS One
Diego A Mesa, Justin Tantiongloc, Marcela Mendoza, Todd P Coleman
The need to reason about uncertainty in large, complex, and multimodal data sets has become increasingly common across modern scientific environments. The ability to transform samples from one distribution <mml:math xmlns:mml=""> <mml:mi>P</mml:mi> </mml:math> to another distribution <mml:math xmlns:mml=""> <mml:mi>Q</mml:mi> </mml:math> enables the solution to many problems in machine learning (e...
February 14, 2019: Neural Computation
Botao Xie, Jinke Li, Xuefeng Zhao
Smartphones which are built into the suite of sensors, network transmission, data storage, and embedded processing capabilities provide a wide range of response measurement opportunities for structural health monitoring (SHM). The objective of this work was to evaluate and validate the use of smartphones for monitoring damage states in a three-dimensional (3D) steel frame structure subjected to shaking table earthquake excitation. The steel frame is a single-layer structure with four viscous dampers mounted at the beam-column joints to simulate different damage states at their respective locations...
February 12, 2019: Sensors
Blanca Vera-Gargallo, Taniya Roy Chowdhury, Joseph Brown, Sarah J Fansler, Ana Durán-Viseras, Cristina Sánchez-Porro, Vanessa L Bailey, Janet K Jansson, Antonio Ventosa
Increasing salinization in wetland systems is a major threat to ecosystem services carried out by microbial communities. Thus, it is paramount to understand how salinity drives both microbial community structures and their diversity. Here we evaluated the structure and diversity of the prokaryotic communities from a range of highly saline soils (EC1:5 from 5.96 to 61.02 dS/m) from the Odiel Saltmarshes and determined their association with salinity and other soil physicochemical features by analyzing 16S rRNA gene amplicon data through minimum entropy decomposition (MED)...
February 11, 2019: Scientific Reports
Alexis M Cahalane, Aoife Kilcoyne, Azadeh Tabari, Shaunagh McDermott, Michael S Gee
BACKGROUND: Differentiation of benign from malignant lymphadenopathy remains challenging in pediatric radiology. Textural analysis (TA) quantitates heterogeneity of tissue signal intensities and has been applied to analysis of CT images. OBJECTIVE: The purpose of this study was to establish whether CT textural analysis of enlarged lymph nodes visualized on pediatric CT can distinguish benign from malignant lymphadenopathy. MATERIALS AND METHODS: We retrospectively identified enlarged lymph nodes measuring 10-20 mm on contrast-enhanced CTs of patients age 18 years and younger that had been categorized as benign or malignant based on the known diagnoses...
February 11, 2019: Pediatric Radiology
Purushottam D Dixit, Ken A Dill
Markov State Models (MSMs) describe the rates and routes in conformational dynamics of biomolecules. Computational estimation of MSMs can be expensive because molecular simulations are slow to find and sample the rare transient events. We describe here an efficient approximate way to determine MSM rate matrices by combining maximum caliber (maximizing path entropies) with optimal transport theory (minimizing some path cost function, as when routing trucks on transportation networks) to patch together transient dynamical information from multiple non-equilibrium simulations...
February 7, 2019: Journal of Chemical Physics
David Perpetuini, Daniela Cardone, Antonio Maria Chiarelli, Chiara Filippini, Pierpaolo Croce, Filippo Zappasodi, Ludovica Rotunno, Nelson Anzoletti, Michele Zito, Arcangelo Merla
Alzheimer's disease (AD) is characterized by progressive memory failures and visuo-spatial impairment. Moreover, AD can be accompanied by autonomic system alterations, which, among others, affect thermoregulatory activity. We here investigated differences in autonomic activity between AD patients and healthy controls (HC) employing a complexity analysis of functional infrared imaging (fIRI) data acquired at rest and during the execution of clinical cognitive and mnemonic tests. FIRI allows for contact-less monitoring of autonomic activity and its thermoregulatory expression without interfering with the psychophysiological state of the subject preserving the free interaction with the doctor...
February 8, 2019: Physiological Measurement
Yu Zhang, Xinbo Gao, Lihuo He, Wen Lu, Ran He
Nowadays, video quality assessment (VQA) is essential to video compression technology applied to video transmission and storage. However, small-scale video quality databases with imbalanced samples and low-level feature representations for distorted videos impede the development of VQA methods. In this paper, we propose a full-reference (FR) VQA metric integrating transfer learning with a convolutional neural network (CNN). First, we imitate the feature-based transfer learning framework to transfer the distorted images as the related domain, which enriches the distorted samples...
February 6, 2019: IEEE Transactions on Neural Networks and Learning Systems
Hans Jonas Meyer, Leonard Leifels, Gordian Hamerla, Anne Kathrin Höhn, Alexey Surov
Background: Our purpose was to elucidate possible correlations between histogram parameters derived from dynamic contrast-enhanced MRI (DCE-MRI) with several histopathological features in head and neck squamous cell carcinomas (HNSCC). Methods: Thirty patients with primary HNSCC were prospectively acquired. Histogram analysis was derived from the DCE-MRI parameters: K trans , K ep , and V e . Additionally, in all cases, expression of human papilloma virus (p16) hypoxia-inducible factor-1-alpha (Hif1-alpha), vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), and tumor suppressor protein p53 were estimated...
2019: Contrast Media & Molecular Imaging
Sachit Butail, Maurizio Porfiri
Detecting causal relationships in complex systems from the time series of the individual units is a pressing area of research that has attracted the interest of a broad community. As an open area of study, this entails the development of methodologies to unravel causal relationships that evolve over time, such as switching of leader-follower roles in animal groups. Here, we augment the information theoretic measure of transfer entropy to establish a fitness function suitable for optimal partitioning of time series data to robustly detect leadership switches in collective behavior...
January 2019: Chaos
Zhaoyi Guan, Zhiqiang Liao, Ke Li, Peng Chen
To precisely diagnose the rotating machinery structural faults, especially structural faults under low rotating speeds, a novel scheme based on combination of empirical mode decomposition (EMD), sample entropy, and deep belief network (DBN) is proposed in this paper. EMD can decompose a signal into several intrinsic mode functions (IMFs) with different signal-to-noise ratios (SNRs) and sample entropy is performed to extract the signals that carry fault information with high SNR. The extracted fault signal is reconstructed into a new vibration signal that will carry abundant fault information...
January 30, 2019: Sensors
Peijian Shi, Weili Ren, Tianxiang Zheng, Zhongming Ren, Xueling Hou, Jianchao Peng, Pengfei Hu, Yanfei Gao, Yunbo Zhong, Peter K Liaw
Realizing improved strength-ductility synergy in eutectic alloys acting as in situ composite materials remains a challenge in conventional eutectic systems, which is why eutectic high-entropy alloys (EHEAs), a newly-emerging multi-principal-element eutectic category, may offer wider in situ composite possibilities. Here, we use an AlCoCrFeNi2.1 EHEA to engineer an ultrafine-grained duplex microstructure that deliberately inherits its composite lamellar nature by tailored thermo-mechanical processing to achieve property combinations which are not accessible to previously-reported reinforcement methodologies...
January 30, 2019: Nature Communications
Till Siebenmorgen, Martin Zacharias
The accurate prediction of protein-protein complex geometries is of major importance to ultimately model the complete interactome of interacting proteins in a cell. A major bottleneck is the realistic free energy evaluation of predicted docked structures. Typically, simple scoring functions applied to single-complex structures are employed that neglect conformational entropy and often solvent effects completely. The binding free energy of a predicted protein-protein complex can, however, be calculated using umbrella sampling (US) along a predefined dissociation/association coordinate of a complex...
February 15, 2019: Journal of Chemical Theory and Computation
Rahul Soni, Manivannan Muniyandi
Context: Reliable quantitative measure of meditation is still elusive. Although electroencephalogram (EEG) and heart rate variability (HRV) are known as quantitative measures of meditation, effects of meditation on EEG and HRV may well take long time as these measures are involuntarily controlled. Effect of mediation on respiration is well known; however, quantitative measures of respiration during meditation have not been studied. Aims: Breath rate variability (BRV) as an alternate measure of meditation even over a short duration is proposed...
January 2019: International Journal of Yoga
Li Yuan, Yanchao Yuan, Zhuhuang Zhou, Yanping Bai, Shuicai Wu
In this paper, a fetal electrocardiogram (ECG) monitoring system based on the Android smartphone was proposed. We designed a portable low-power fetal ECG collector, which collected maternal abdominal ECG signals in real time. The ECG data were sent to a smartphone client via Bluetooth. Smartphone app software was developed based on the Android system. The app integrated the fast fixed-point algorithm for independent component analysis (FastICA) and the sample entropy algorithm, for the sake of real-time extraction of fetal ECG signals from the maternal abdominal ECG signals...
January 22, 2019: Sensors
Ze-Qun Zhang, Kai-Kai Song, Shu Guo, Qi-Sen Xue, Hui Xing, Chong-De Cao, Fu-Ping Dai, Bernhard Völker, Anton Hohenwarter, Tapabrata Maity, Niraj Chawake, Jeong-Tae Kim, Li Wang, Ivan Kaban, Jürgen Eckert
High-entropy alloys (HEAs) have inspired considerable interest due to their attractive physical and mechanical properties. In this work, the microstructural evolution induced by different heat treatments on rapidly solidified hypoeutectic precursors of a Fe26.7 Co26.7 Ni26.7 Si8.9 B11 HEA is investigated and correlated with the corresponding mechanical properties. The microstructures of the rapidly solidified precursors are composed of primary fcc solid solution dendrites embedded in a eutectic matrix. When the samples are annealed at different temperatures after furnace cooling or quenching, respectively, the eutectic structure gradually decomposes into fcc, tetragonal (Fe,Co)2 B, and hexagonal Ni31 Si12 crystals with increasing annealing temperature, leading to a gradual increase of the content of the fcc crystals and both their aggregation and coarsening...
January 23, 2019: Scientific Reports
María E Botello-Zubiate, María C Grijalva-Castillo, Daniel Soto-Parra, Renee J Sáenz-Hernández, Carlos R Santillán-Rodríguez, José A Matutes-Aquino
Manganites of the family La0.7 Ca0.3-x Srx MnO₃ were fabricated by four preparation methods: (a) the microwave-assisted sol-gel Pechini method; (b) sol-gel Pechini chemical synthesis; (c) solid-state reaction with a planetary mill; and (d) solid-state reaction with an attritor mill, in order to study the effect of the preparation route used on its magnetocaloric and magnetic properties. In addition, the manganites manufactured by the Pechini sol-gel method were compacted using Spark Plasma Sintering (SPS) to determine how the consolidation process influences its magnetocaloric properties...
January 19, 2019: Materials
Stephen M Glass, Christopher K Rhea, Randy J Schmitz, Scott E Ross
CONTEXT: Movement screening has become increasingly popular among tactical professionals. This popularity has motivated the design of interventions that cater to improving outcomes on the screens themselves, which are often scored in reference to an objective norm. In contrast to the assumptions underlying this approach, dynamical systems theory suggests that movements arise as a function of continuously evolving constraints and that optimal movement strategies may not exist. To date, few data address behavioral complexity in the fundamental movement tasks commonly used in clinical screenings...
January 18, 2019: Journal of Athletic Training
Felipe Da Rocha Henriques, Lisandro Lovisolo, Eduardo Antônio Barros da Silva
We consider a Wireless Sensor Network (WSN) monitoring environmental data. Compressive Sensing (CS) is explored to reduce the number of coefficients to transmit and consequently save the energy of sensor nodes. Each sensor node collects N samples of environmental data, these are CS coded to transmit M < N values to a sink node. The M CS coefficients are uniformly quantized and entropy coded. We investigate the rate-distortion performance of this approach even under CS coefficient losses. The results show the robustness of the CS coding framework against packet loss...
January 11, 2019: Sensors
Kristoffer Larsen Norheim, Afshin Samani, Jakob Hjort Bønløkke, Øyvind Omland, Pascal Madeleine
The present study investigated the influence of age and musculoskeletal pain on force variability during a continuous isometric handgrip force task performed at 30% of maximal voluntary contraction carried out until failure. We recruited 96 male manual workers aged 51-72 years. The participants were stratified according to their age (50-59 and 60+ years) and by pain status (no pain, acute pain and chronic pain). The amplitude and structure of variability expressed as respectively standard deviation (SD) and coefficient of variation (CV), and sample entropy (SaEn) were calculated from the endurance task...
January 11, 2019: Human Movement Science
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"