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https://www.readbyqxmd.com/read/29328646/vibrational-properties-of-bulk-boric-acid-2a-and-3t-polymorphs-and-their-two-dimensional-layers-measurements-and-density-functional-theory-calculations
#1
Mauricelio Bezerra da Silva, Regina C R Santos, Paulo T C Freire, Ewerton W S Caetano, Valder N Freire
Boric acid (H3BO3) is being used effectively nowadays in traps/baits for the management of Aedes aegypti L. and Aedes albopictus Skuse species of mosquitoes, which are the main spreading vectors worldwide for diseases like malaria, dengue and zika. Previously, we have published results on the structural, electronic and optical properties of its molecular triclinic H3BO3-2A and trigonal H3BO3-3T polymorphs within the framework of density functional theory (DFT). Due to the renewed importance of these materials, the focus of this work is on the vibrational properties of the bulk boric acid 2A and 3T polymorphs...
January 12, 2018: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29315883/spin-crossover-in-a-hexaamineiron-ii-complex-experimental-confirmation-of-a-computational-prediction
#2
Paul V Bernhardt, Jessica K Bilyj, Victor Brosius, Dmitry Chernyshov, Robert J Deeth, Marco Foscato, Vidar R Jensen, Nicole Mertes, Mark J Riley, Karl W Törnroos
Single crystal structural analysis of [FeII(tame)₂]Cl₂·MeOH (tame = 1,1,1-tris(aminomethyl)ethane) as a function of temperature reveals a smooth crossover between a high temperature high-spin octahedral d⁶ state and a low temperature low-spin ground state without any change of the symmetry of the crystal structure. The temperature at which the high and low spin states are present in equal proportions is T1/2 = 140 K. Single crystal, variable-temperature optical spectroscopy of [FeII(tame)₂]Cl₂·MeOH is consistent with this change in electronic ground state...
January 6, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29303373/cardiac-autonomic-function-and-reactivity-tests-in-physically-active-subjects-with-moderately-severe-copd
#3
Jibril Mohammed, Eric Derom, Tine De Backer, Inge De Wandele, Patrick Calders
Patients with chronic obstructive pulmonary disease (COPD) show impairments in the autonomic nervous systems (ANS) function, which is responsible for cardiac autonomic regulation. This study assessed the autonomic function and cardio-vagal reactivity in conveniently sampled subjects with COPD participating in a pulmonary rehabilitation (PR) program. Twenty-six subjects with COPD and 22 age and gender matched control subjects were evaluated. R-R intervals were collected at rest in supine position. Thereafter, resting autonomic function parameters comprising linear and nonlinear analyses of heart rate variability (HRV) and baroreceptor sensitivity (BRS) were calculated...
January 5, 2018: COPD
https://www.readbyqxmd.com/read/29286719/essentially-entropic-lattice-boltzmann-model
#4
Mohammad Atif, Praveen Kumar Kolluru, Chakradhar Thantanapally, Santosh Ansumali
The entropic lattice Boltzmann model (ELBM), a discrete space-time kinetic theory for hydrodynamics, ensures nonlinear stability via the discrete time version of the second law of thermodynamics (the H theorem). Compliance with the H theorem is numerically enforced in this methodology and involves a search for the maximal discrete path length corresponding to the zero dissipation state by iteratively solving a nonlinear equation. We demonstrate that an exact solution for the path length can be obtained by assuming a natural criterion of negative entropy change, thereby reducing the problem to solving an inequality...
December 15, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/29281196/effects-of-prolonged-and-repeated-immersions-on-heart-rate-variability-and-complexity-in-military-divers
#5
Nathaniel T Berry, Laurie Wideman, Christopher K Rhea, Jeffrey D Labban, Ki H Chon, Barbara E Shykoff, Jay Harran, John P Florian
BACKGROUND: The influence of prolonged and repeated water immersions on heart rate variability (HRV) and complexity was examined in 10 U.S. Navy divers who completed six-hour resting dives on five consecutive days. Pre-dive and during-dive measures were recorded daily. METHODS: Dependent variables of interest were average heart rate (HR), time-domain measures of HRV [root mean square of successive differences of the normal RR (NN) interval (RMSSD), standard deviation of the NN interval (SDNN)], frequency-domain measures of HRV [low-frequency power spectral density (psd) (LFpsd), low-frequency normalized (LFnu), high-frequency psd (HFpsd), high-frequency normalized (HFnu), low-frequency/ high-frequency ratio (LF/HF)], and non-linear dynamics of HRV [approximate entropy (ApEn)]...
November 2017: Undersea & Hyperbaric Medicine: Journal of the Undersea and Hyperbaric Medical Society, Inc
https://www.readbyqxmd.com/read/29275873/current-and-potential-future-distribution-of-the-american-dog-tick-dermacentor-variabilis-say-in-north-america
#6
Jordan N Minigan, Heather A Hager, Andrew S Peregrine, Jonathan A Newman
The American dog tick (Dermacentor variabilis) is medically and economically important in North America. This species is found across central and eastern North America from the Gulf Coast of Mexico through southern Canada. In parts of this region, D. variabilis is a vector for pathogens that cause diseases in humans and animals. Our aim was to determine whether climate change would affect the distribution of the climatically suitable area for D. variabilis in North America, to aid monitoring for potential future spread of tick-borne pathogens...
December 8, 2017: Ticks and Tick-borne Diseases
https://www.readbyqxmd.com/read/29251059/epileptic-seizure-detection-using-dwt-based-approximate-entropy-shannon-entropy-and-support-vector-machine-a-case-study
#7
A Sharmila, Suman Aman Raj, Pandey Shashank, P Mahalakshmi
In this work, we have used a time-frequency domain analysis method called discrete wavelet transform (DWT) technique. This method stand out compared to other proposed methods because of its algorithmic elegance and accuracy. A wavelet is a mathematical function based on time-frequency analysis in signal processing. It is useful particularly because it allows a weak signal to be recovered from a noisy signal without much distortion. A wavelet analysis works by analysing the image and converting it to mathematical function which is decoded by the receiver...
December 18, 2017: Journal of Medical Engineering & Technology
https://www.readbyqxmd.com/read/29249572/the-changes-in-classical-and-nonlinear-parameters-after-a-maximal-bout-to-elicit-fatigue-in-competitive-swimming
#8
Tiago M Barbosa, Simin Chen, Jorge E Morais, Mário J Costa, Nuno Batalha
The aim was to assess the effect of fatigue on linear and nonlinear parameters in swimming. Twenty-four fitness-oriented swimmers performed a maximal bout of 100 m at front-crawl to elicit fatigue. Before (pre-) and immediately after (post-test) the bout, participants swam an all-out 25 m to derive the speed fluctuation (dv), approximate entropy (ApEn) and fractal dimension (FD) from the speed-time series collected by a speedo-meter. Swim speed was 10.85% slower in the post-test than in the pre-test (p < ...
December 15, 2017: Human Movement Science
https://www.readbyqxmd.com/read/29246041/testing-the-mutual-information-expansion-of-entropy-with-multivariate-gaussian-distributions
#9
Martin Goethe, Ignacio Fita, J Miguel Rubi
The mutual information expansion (MIE) represents an approximation of the configurational entropy in terms of low-dimensional integrals. It is frequently employed to compute entropies from simulation data of large systems, such as macromolecules, for which brute-force evaluation of the full configurational integral is intractable. Here, we test the validity of MIE for systems consisting of more than m = 100 degrees of freedom (dofs). The dofs are distributed according to multivariate Gaussian distributions which were generated from protein structures using a variant of the anisotropic network model...
December 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29244951/interfacial-adsorption-of-neutral-and-ionic-solutes-in-a-water-droplet
#10
Patrick K Wise, Dor Ben-Amotz
Direct (solute-water) and indirect (water-water) contributions to adsorption at an air-water interface are identified using the Widom potential distribution theorem and quantified using molecular dynamics simulations of a liquid water droplet containing either neopentane or iodide-like solutes with charges of 0 or ±1. The results are used to quantitatively compare direct and indirect, energetic and entropic, contributions to adsorption, as well as to critically test surface capillary wave, linear response (LR), and mean field (MF) predictions...
December 15, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/29223283/regulatory-aspects-of-the-human-hypothalamus-pituitary-thyroid-axis
#11
REVIEW
Ferdinand Roelfsema, Anita Boelen, Andries Kalsbeek, Eric Fliers
Thyroid hormones are essential for growth, differentiation and metabolism during prenatal and postnatal life. The hypothalamus-pituitary-thyroid (HPT)-axis is optimized for these actions. Knowledge of this hormonal axis is derived from decades of experiments in animals and man, and more recently from spontaneous mutations in man and constructed mutations in mice. This review examines the HPT-axis in relation to 24 h TSH profiles in men in various physiological and pathophysiological conditions, including obesity, age, longevity, and primary as well as central hypothyroidism...
October 2017: Best Practice & Research. Clinical Endocrinology & Metabolism
https://www.readbyqxmd.com/read/29222477/a-novel-eeg-based-spectral-analysis-of-persistent-brain-function-alteration-in-athletes-with-concussion-history
#12
Tamanna T K Munia, Ali Haider, Charles Schneider, Mark Romanick, Reza Fazel-Rezai
The neurocognitive sequelae of a sport-related concussion and its management are poorly defined. Detecting deficits are vital in making a decision about the treatment plan as it can persist one year or more following a brain injury. The reliability of traditional cognitive assessment tools is debatable, and thus attention has turned to assessments based on electroencephalogram (EEG) to evaluate subtle post-concussive alterations. In this study, we calculated neurocognitive deficits combining EEG analysis with three standard post-concussive assessment tools...
December 8, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29220351/driver-fatigue-detection-through-multiple-entropy-fusion-analysis-in-an-eeg-based-system
#13
Jianliang Min, Ping Wang, Jianfeng Hu
Driver fatigue is an important contributor to road accidents, and fatigue detection has major implications for transportation safety. The aim of this research is to analyze the multiple entropy fusion method and evaluate several channel regions to effectively detect a driver's fatigue state based on electroencephalogram (EEG) records. First, we fused multiple entropies, i.e., spectral entropy, approximate entropy, sample entropy and fuzzy entropy, as features compared with autoregressive (AR) modeling by four classifiers...
2017: PloS One
https://www.readbyqxmd.com/read/29208686/effects-of-growth-hormone-administration-on-luteinizing-hormone-secretion-in-healthy-older-men-and-women
#14
Ranganath Muniyappa, Shannon D Sullivan, Sri Harsha Tella, Brent S Abel, S Mitchell Harman, Marc R Blackman
The known interactions between the somatotropic and hypothalamic-pituitary-gonadal (HPG) axes have not been well delineated in older individuals. Aging-associated decline in insulin like growth factor-1 (IGF-1) levels has been proposed to play a role in reproductive senescence in animals. However, the effects of GH on LH secretion are unknown in older individuals. Our objective was to determine whether GH modulates LH secretion or levels of sex steroids (SS) in healthy older (ages 65-88 years) men (n = 24) and women (n = 24) with low-normal plasma IGF-1 levels...
December 2017: Physiological Reports
https://www.readbyqxmd.com/read/29202357/effect-of-parameter-selection-on-entropy-calculation-for-long-walking-trials
#15
Jennifer M Yentes, William Denton, John McCamley, Peter C Raffalt, Kendra K Schmid
It is sometimes difficult to obtain uninterrupted data sets that are long enough to perform nonlinear analysis, especially in pathological populations. It is currently unclear as to how many data points are needed for reliable entropy analysis. The aims of this study were to determine the effect of changing parameter values of m, r, and N on entropy calculations for long gait data sets using two different modes of walking (i.e., overground versus treadmill). Fourteen young adults walked overground and on a treadmill at their preferred walking speed for one-hour while step time was collected via heel switches...
November 28, 2017: Gait & Posture
https://www.readbyqxmd.com/read/29200933/dimensions-of-biodiversity-loss-spatial-mismatch-in-land-use-impacts-on-species-functional-and-phylogenetic-diversity-of-european-bees
#16
Adriana De Palma, Michael Kuhlmann, Rob Bugter, Simon Ferrier, Andrew J Hoskins, Simon G Potts, Stuart P M Roberts, Oliver Schweiger, Andy Purvis
Aim: Agricultural intensification and urbanization are important drivers of biodiversity change in Europe. Different aspects of bee community diversity vary in their sensitivity to these pressures, as well as independently influencing ecosystem service provision (pollination). To obtain a more comprehensive understanding of human impacts on bee diversity across Europe, we assess multiple, complementary indices of diversity. Location: One Thousand four hundred and forty six sites across Europe...
December 2017: Diversity & Distributions
https://www.readbyqxmd.com/read/29185994/linear-and-nonlinear-features-of-fetal-heart-rate-on-the-assessment-of-fetal-development-in-the-course-of-pregnancy-and-the-impact-of-fetal-gender
#17
Kyriaki Spyridou, Ioanna Chouvarda, Leontios J Hadjileontiadis, Nic Maglaveras
OBJECTIVE: This work aims to investigate the impact of gestational age and fetal gender on fetal heart rate (FHR) tracings. STUDY DESIGN: Different linear and non-linear parameters indicating correlation or complexity were used to study the influence of fetal age and gender on FHR tracings. The signals were recorded from 99 normal pregnant women in a singleton pregnancy at gestational age from 28 to 40 weeks, before the onset of labor. 56 of the fetuses were female and 43 were male...
November 29, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/29182347/efficient-and-adaptive-methods-for-computing-accurate-potential-surfaces-for-quantum-nuclear-effects-applications-to-hydrogen-transfer-reactions
#18
Nicole DeGregorio, Srinivasan Sesha Iyengar
We present two sampling measures to gauge critical regions of potential energy surfaces. These sampling measures employ (a) the instantaneous quantum wavepacket density, an approximation to the (b) potential surface, its (c) gradients, and (d) a Shannon information theory based expression that estimates the local entropy associated with the quantum wavepacket. These four criteria together enable a directed sampling of potential surfaces that appears to correctly describe the local oscillation frequencies, or the local Nyquist frequency, of a potential surface...
November 28, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/29179887/biomechanical-analysis-of-dance-for-parkinson-s-disease-a-paradoxical-case-study-of-balance-and-gait-effects
#19
Kristen L Sowalsky, Jill Sonke, Lori J P Altmann, Leonardo Almeida, Chris J Hass
OBJECTIVES: This study aimed to measure the effects of a dance training program on subjective and objective balance and gait measures in a person with Parkinson's disease. DESIGN AND SETTING: The participant was measured via clinical scales and biomechanical balance and gait analyses pre- and post-16 weeks of dance participation at the University Center for Arts in Medicine. The dance program consisted of 75 minute sessions three days a week. RESULTS: Improved clinical scales included the Schwab and England scale (+10%), falls efficacy scale (-11 points), six-minute walk (+15...
November 2017: Explore: the Journal of Science and Healing
https://www.readbyqxmd.com/read/29179051/differences-in-pattern-of-variability-for-lower-extremity-kinematics-between-walking-and-running
#20
Amanda Estep, Steven Morrison, Shane Caswell, Jatin Ambegaonkar, Nelson Cortes
This study characterizes walking and running patterns in healthy individuals using linear and nonlinear methods Seventeen individuals (12 males, 5 females) volunteered for the study. 3D kinematic data during walking (WA) and running (RU) on a motorized treadmill were captured using reflective markers placed on lower body (200Hz). A single 25s trial (5000 data points) was collected for each gait task. WA speed was 1.39±0.12m/s, whereas RU speed was 2.56±0.27m/s. Variables of interest included ankle plantar/dorsi flexion, knee flexion/extension, knee abduction/adduction, hip flexion/extension, and hip abduction/adduction angles...
November 21, 2017: Gait & Posture
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