keyword
MENU ▼
Read by QxMD icon Read
search

entropy

keyword
https://www.readbyqxmd.com/read/28820921/analysis-of-cone-mosaic-reflectance-properties-in-healthy-eyes-and-in-eyes-with-nonproliferative-diabetic-retinopathy-over-time
#1
Letizia Mariotti, Nicholas Devaney, Giuseppe Lombardo, Marco Lombardo
Purpose: We investigate the reflectance properties of the cone mosaic in adaptive optics (AO) images of healthy subjects and subjects with nonproliferative diabetic retinopathy (NPDR) over time. Methods: We acquired images of the parafoveal cone mosaic over 5 years in 12 healthy subjects and in six patients with mild NPDR. We analyzed the parameters of the cone intensity histogram distribution (mean, SD, and skewness), two metrics of the cone mosaic texture (sharpness and entropy), and two novel metrics (cone/intercone intensity and slope of the variogram)...
August 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28820287/comparison-of-pet-and-ct-radiomics-for-prediction-of-local-tumor-control-in-head-and-neck-squamous-cell-carcinoma
#2
Marta Bogowicz, Oliver Riesterer, Luisa Sabrina Stark, Gabriela Studer, Jan Unkelbach, Matthias Guckenberger, Stephanie Tanadini-Lang
PURPOSE: An association between radiomic features extracted from CT and local tumor control in the head and neck squamous cell carcinoma (HNSCC) has been shown. This study investigated the value of pretreatment functional imaging (18F-FDG PET) radiomics for modeling of local tumor control. MATERIAL AND METHODS: Data from HNSCC patients (n = 121) treated with definitive radiochemotherapy were used for model training. In total, 569 radiomic features were extracted from both contrast-enhanced CT and 18F-FDG PET images in the primary tumor region...
August 18, 2017: Acta Oncologica
https://www.readbyqxmd.com/read/28820250/coordination-and-thermodynamics-of-trivalent-curium-with-malonate-at-increased-temperatures-a-spectroscopic-and-quantum-chemical-study
#3
Andrej Skerencak-Frech, Michael Trumm, Daniel R Fröhlich, Petra J Panak
The complexation of Cm(III) with malonate is studied by time-resolved laser fluorescence spectroscopy (TRLFS) in the temperature range from 25 to 90 °C. Three complexes ([Cm(Mal)n](3-2n), n = 1, 2, 3) are identified and their molar fractions are determined as a function of the ligand concentration, the ionic strength, and the temperature. A general shift of the chemical equilibrium toward higher complexes with increasing temperature is observed, with the [CmMal3](3-) complex forming only at T > 40 °C. The conditional stability constants (log K'n(T)) are calculated and extrapolated to Im = 0 with the specific ion interaction theory (SIT)...
August 18, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28819297/energy-free-machine-learning-force-field-for-aluminum
#4
Ivan Kruglov, Oleg Sergeev, Alexey Yanilkin, Artem R Oganov
We used the machine learning technique of Li et al. (PRL 114, 2015) for molecular dynamics simulations. Atomic configurations were described by feature matrix based on internal vectors, and linear regression was used as a learning technique. We implemented this approach in the LAMMPS code. The method was applied to crystalline and liquid aluminum and uranium at different temperatures and densities, and showed the highest accuracy among different published potentials. Phonon density of states, entropy and melting temperature of aluminum were calculated using this machine learning potential...
August 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28819293/effects-of-temporal-correlations-in-social-multiplex-networks
#5
Michele Starnini, Andrea Baronchelli, Romualdo Pastor-Satorras
Multi-layered networks represent a major advance in the description of natural complex systems, and their study has shed light on new physical phenomena. Despite its importance, however, the role of the temporal dimension in their structure and function has not been investigated in much detail so far. Here we study the temporal correlations between layers exhibited by real social multiplex networks. At a basic level, the presence of such correlations implies a certain degree of predictability in the contact pattern, as we quantify by an extension of the entropy and mutual information analyses proposed for the single-layer case...
August 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28819260/thermodynamic-and-kinetic-analyses-of-iron-response-element-ire-mrna-binding-to-iron-regulatory-protein-irp1
#6
Mateen A Khan, William E Walden, Elizabeth C Theil, Dixie J Goss
Comparison of kinetic and thermodynamic properties of IRP1 (iron regulatory protein1) binding to FRT (ferritin) and ACO2 (aconitase2) IRE-RNAs, with or without Mn(2+), revealed differences specific to each IRE-RNA. Conserved among animal mRNAs, IRE-RNA structures are noncoding and bind Fe(2+) to regulate biosynthesis rates of the encoded, iron homeostatic proteins. IRP1 protein binds IRE-RNA, inhibiting mRNA activity; Fe(2+) decreases IRE-mRNA/IRP1 binding, increasing encoded protein synthesis. Here, we observed heat, 5 °C to 30 °C, increased IRP1 binding to IRE-RNA 4-fold (FRT IRE-RNA) or 3-fold (ACO2 IRE-RNA), which was enthalpy driven and entropy favorable...
August 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28819153/giant-onsite-electronic-entropy-enhances-the-performance-of-ceria-for-water-splitting
#7
S Shahab Naghavi, Antoine A Emery, Heine A Hansen, Fei Zhou, Vidvuds Ozolins, Chris Wolverton
Previous studies have shown that a large solid-state entropy of reduction increases the thermodynamic efficiency of metal oxides, such as ceria, for two-step thermochemical water splitting cycles. In this context, the configurational entropy arising from oxygen off-stoichiometry in the oxide, has been the focus of most previous work. Here we report a different source of entropy, the onsite electronic configurational entropy, arising from coupling between orbital and spin angular momenta in lanthanide f orbitals...
August 18, 2017: Nature Communications
https://www.readbyqxmd.com/read/28819010/new-insight-on-the-s100a1-stip1-complex-highlights-the-important-relationship-between-allostery-and-entropy-in-protein-function
#8
Nathaniel V Nucci
Calcium signaling serves as a nexus of many vital cellular processes. Of particular importance is the role the calcium signaling plays in the prevention of protein misfolding, and the S100 family of calcium-binding proteins is a key player in this pathway. While the S100 proteins carry out a range of roles, the interaction of S100A1 and the stress-inducible phosphoprotein 1 (STIP1) has been shown to be particularly important. A recent study by Maciejewski et al. in Biochemical Journal (Biochemical Journal (2017) 474, 1853-1866) revealed new insights into the nature of the S100A1-STIP1 interaction...
August 17, 2017: Biochemical Journal
https://www.readbyqxmd.com/read/28817712/study-of-the-cross-market-effects-of-brexit-based-on-the-improved-symbolic-transfer-entropy-garch-model-an-empirical-analysis-of-stock-bond-correlations
#9
Xiurong Chen, Yixiang Tian, Rubo Zhao
In this paper, we study the cross-market effects of Brexit on the stock and bond markets of nine major countries in the world. By incorporating information theory, we introduce the time-varying impact weights based on symbolic transfer entropy to improve the traditional GARCH model. The empirical results show that under the influence of Brexit, flight-to-quality not only commonly occurs between the stocks and bonds of each country but also simultaneously occurs among different countries. We also find that the accuracy of the time-varying symbolic transfer entropy GARCH model proposed in this paper has been improved compared to the traditional GARCH model, which indicates that it has a certain practical application value...
2017: PloS One
https://www.readbyqxmd.com/read/28817630/pet-snakes-illegally-marketed-in-brazil-climatic-viability-and-establishment-risk
#10
Érica Fonseca, Mirco Solé, Dennis Rödder, Paulo de Marco
Invasive species are one among many threats to biodiversity. Brazil has been spared, generically, of several destructive invasive species. Reports of invasive snakes' populations are nonexistent, but the illegal pet trade might change this scenario. Despite the Brazilian laws forbid to import most animals, illegal trade is frequently observed and propagules are found in the wild. The high species richness within Brazilian biomes and accelerated fragmentation of natural reserves are a critical factors facilitating successful invasion...
2017: PloS One
https://www.readbyqxmd.com/read/28817596/potential-effects-of-climate-change-on-members-of-the-palaeotropical-pitcher-plant-family-nepenthaceae
#11
Laura K Gray, Charles Clarke, G R William Wint, Jonathan A Moran
Anthropogenic climate change is predicted to have profound effects on species distributions over the coming decades. In this paper, we used maximum entropy modelling (Maxent) to estimate the effects of projected changes in climate on extent of climatically-suitable habitat for two Nepenthes pitcher plant species in Borneo. The model results predicted an increase in area of climatically-suitable habitat for the lowland species Nepenthes rafflesiana by 2100; in contrast, the highland species Nepenthes tentaculata was predicted to undergo significant loss of climatically-suitable habitat over the same period...
2017: PloS One
https://www.readbyqxmd.com/read/28816684/a-multiobjective-evolutionary-algorithm-based-on-structural-and-attribute-similarities-for-community-detection-in-attributed-networks
#12
Zhangtao Li, Jing Liu, Kai Wu
Most of the existing community detection algorithms are based on vertex connectivity. While in many real networks, each vertex usually has one or more attributes describing its properties which are often homogeneous in a cluster. Such networks can be modeled as attributed graphs, whose attributes sometimes are equally important to topological structure in graph clustering. One important challenge is to detect communities considering both topological structure and vertex properties simultaneously. To this propose, a multiobjective evolutionary algorithm based on structural and attribute similarities (MOEA-SA) is first proposed to solve the attributed graph clustering problems in this paper...
August 16, 2017: IEEE Transactions on Cybernetics
https://www.readbyqxmd.com/read/28816657/a-dynamic-regression-approach-for-frequency-domain-partial-coherence-and-causality-analysis-of-functional-brain-networks
#13
Lipeng Ning, Yogesh Rathi
Coherence and causality measures are often used to analyze the influence of one region on another during analysis of functional brain networks. The analysis methods usually involve a regression problem where the signal of interest is decomposed into a mixture of regressor and a residual signal. In this paper, we revisit this basic problem and present solutions that provide the minimal-entropy residuals for different types of regression filters, such as causal, instantaneously causal and noncausal filters. Using optimal prediction theory, we derive several novel frequency-domain expressions for partial coherence, causality and conditional causality analysis...
August 14, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28816654/instantaneous-transfer-entropy-for-the-study-of-cardiovascular-and-cardio-respiratory-nonstationary-dynamics
#14
Gaetano Valenza, Luca Faes, Luca Citi, Michele Orini, Riccardo Barbieri
Measures of Transfer Entropy (TE) quantify the direction and strength of coupling between two complex systems. Standard approaches assume stationarity of the observations, and therefore are unable to track time-varying changes in nonlinear information transfer with high temporal resolution. In this study, we aim to define and validate novel instantaneous measures of transfer entropy to provide an im- proved assessment of complex non-stationary cardio-respiratory interactions.
August 15, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28815634/effect-of-trapping-methods-on-the-estimation-of-alpha-diversity-of-a-phlebotomine-sandfly-assemblage-in-southern-mexico
#15
J J Rodríguez-Rojas, E A Rebollar-Téllez
The aims of the study were to (a) investigate the effect of trapping methods on alpha diversity; and (b) enhance the knowledge of the sandfly assemblage in the state of Quintana Roo. Field work was undertaken in a tropical forest of southern Mexico from August 2013 to July 2014. Sampling was conducted monthly during three consecutive nights. For each trapping night, 12 different types of trap were operated from 18.00 to 24.00 hours in four transects. Measures of alpha community diversity were based on the quantification of the number of species (Chao 2, Jackknife 2, Clench's equation, Margalef's index) and the community structure, as well as the dominance (Simpson and Berger-Parker indexes) and evenness (Shannon's entropy index, true diversity of the Jost and Pielou index)...
August 17, 2017: Medical and Veterinary Entomology
https://www.readbyqxmd.com/read/28814850/increased-parasympathetic-cardiac-modulation-in-patients-with-acute-exacerbation-of-copd-how-should-we-interpret-it
#16
Erika Zavaglia Kabbach, Adriana Mazzuco, Audrey Borghi-Silva, Ramona Cabiddu, Aline Galvão Agnoleto, Jessica Fernanda Barbosa, Luiz Carlos Soares de Carvalho Junior, Renata Gonçalves Mendes
BACKGROUND: Cardiac autonomic modulation (CAM) is impaired in patients with stable COPD. Exacerbation aggravates the patients' health status and functional capacity. While the clinical and functional effects of exacerbation are known, no studies investigated CAM during exacerbation and whether there is a relationship between CAM and functional capacity and dyspnea. METHODS: Thirty-two patients with moderate to severe COPD were enrolled into two groups: stable COPD (GSta, n=16) and acute exacerbation of COPD (GAE, n=16)...
2017: International Journal of Chronic Obstructive Pulmonary Disease
https://www.readbyqxmd.com/read/28813925/stereo-3d-tracking-of-infants-in-natural-play-conditions
#17
Shreyas S Shivakumar, Helen Loeb, Daniel K Bogen, Frances Shofer, Phillip Bryant, Laura Prosser, Michelle J Johnson
This paper describes the design and implementation of a multiple view stereoscopic 3D vision system and a supporting infant tracker pipeline to track limb movement in natural play environments and identify potential metrics to quantify movement behavior. So far, human pose estimation and tracking with 3D cameras has been focused primarily on adults and cannot be directly extended to infants because of differences in visual features such as shapes, sizes and appearance. With rehabilitation in mind, we propose a portable, compact, markerless, low cost and high resolution 3D vision system and a tracking algorithm that exploits infant appearance attributes and depth information...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813867/therapeutic-effects-of-anti-gravity-treadmill-alterg-training-on-reflex-hyper-excitability-corticospinal-tract-activities-and-muscle-stiffness-in-children-with-cerebral-palsy
#18
Sh Parvin, A Taghiloo, A Irani, M Mehdi Mirbagheri
We aimed to study therapeutic effects of antigravity treadmill (AlterG) training on reflex hyper-excitability, muscle stiffness, and corticospinal tract (CST) function in children with spastic hemiplegic cerebral palsy (CP). Three children received AlterG training 3 days per week for 8 weeks as experimental group. Each session lasted 45 minutes. One child as control group received typical occupational therapy for the same amount of time. We evaluated hyper-excitability of lower limb muscles by H-reflex response...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813004/lactose-binding-induces-opposing-dynamics-changes-in-human-galectins-revealed-by-nmr-based-hydrogen-deuterium-exchange
#19
Chih-Ta Henry Chien, Meng-Ru Ho, Chung-Hung Lin, Shang-Te Danny Hsu
Galectins are β-galactoside-binding proteins implicated in a myriad of biological functions. Despite their highly conserved carbohydrate binding motifs with essentially identical structures, their affinities for lactose, a common galectin inhibitor, vary significantly. Here, we aimed to examine the molecular basis of differential lactose affinities amongst galectins using solution-based techniques. Consistent dissociation constants of lactose binding were derived from nuclear magnetic resonance (NMR) spectroscopy, intrinsic tryptophan fluorescence, isothermal titration calorimetry and bio-layer interferometry for human galectin-1 (hGal1), galectin-7 (hGal7), and the N-terminal and C-terminal domains of galectin-8 (hGal8(NTD) and hGal8(CTD), respectively)...
August 16, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28811468/inferring-structural-connectivity-using-ising-couplings-in-models-of-neuronal-networks
#20
Balasundaram Kadirvelu, Yoshikatsu Hayashi, Slawomir J Nasuto
Functional connectivity metrics have been widely used to infer the underlying structural connectivity in neuronal networks. Maximum entropy based Ising models have been suggested to discount the effect of indirect interactions and give good results in inferring the true anatomical connections. However, no benchmarking is currently available to assess the performance of Ising couplings against other functional connectivity metrics in the microscopic scale of neuronal networks through a wide set of network conditions and network structures...
August 15, 2017: Scientific Reports
keyword
keyword
31717
1
2
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"