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https://www.readbyqxmd.com/read/28819942/study-of-the-relationship-between-ages-and-oxidative-stress-damage-to-trophoblast-cell-mitochondria
#1
Lingling Jiang, Jianying Yan, Lixiang Wu
OBJECTIVES: To study the influence of AGEs on placental trophoblast mitochondria oxidative stress, and to explore the possible pathogenesis which may participate in pre-eclampsia. MATERIAL AND METHODS: Human trophoblast cells from early pregnancy were cultured by an enzyme-digestion method. When trophoblast cells reached approximately 70-80% after passages, they were incubated with pre-eclampsia serum for 24 hours. A fluorescent dye assay was applied to measure the mitochondrial membrane potential; ELISA was used to measure the activity of the mitochondrial permeability transition pore...
2017: Ginekologia Polska
https://www.readbyqxmd.com/read/28816177/electrical-stimulation-of-gut-motility-guided-by-an-in-silico-model
#2
Bradley Brigham Barth, Craig S Henriquez, Warren M Grill, Xiling Shen
OBJECTIVE: Neuromodulation of the central and peripheral nervous systems is becoming increasingly important for treating a diverse set of diseases-ranging from Parkinson's Disease and epilepsy to chronic pain. However, neuromodulation of the gastrointestinal (GI) tract has achieved relatively limited success in treating functional GI disorders, which affect a significant population, because the effects of stimulation on the enteric nervous system (ENS) and gut motility are not well understood...
August 17, 2017: Journal of Neural Engineering
https://www.readbyqxmd.com/read/28810753/dynamical-transition-in-molecular-glasses-and-proteins-observed-by-spin-relaxation-of-nitroxide-spin-probes-and-labels
#3
Elena A Golysheva, Georgiy Yu Shevelev, Sergei A Dzuba
In glassy substances and biological media, dynamical transitions are observed in neutron scattering that manifests itself as deviations of the translational mean-squared displacement, 〈x(2)〉, of hydrogen atoms from harmonic dynamics. In biological media, the deviation occurs at two temperature intervals, at ∼100-150 K and at ∼170-230 K, and it is attributed to the motion of methyl groups in the former case and to the transition from harmonic to anharmonic or diffusive motions in the latter case. In this work, electron spin echo (ESE) spectroscopy-a pulsed version of electron paramagnetic resonance-is applied to study the spin relaxation of nitroxide spin probes and labels introduced in molecular glass former o-terphenyl and in protein lysozyme...
August 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28783442/a-literature-review-on-current-and-proposed-technologies-of-noninvasive-blood-pressure-measurement
#4
Ramtanu Mukherjee, Sanchita Ghosh, Bharat Gupta, Tapas Chakravarty
BACKGROUND: Noninvasive continuous blood pressure (BP) measurement has become an evolving topic in the field of remote healthcare. The classical noninvasive BP measurement techniques provide spontaneous values of systolic and diastolic BP. On the other hand, intrusive type BP measurement techniques provide continuous values of systolic and diastolic BP. However, these techniques are very painful, cannot be used for long-term monitoring, and are obtainable only in an intensive care unit environment...
August 7, 2017: Telemedicine Journal and E-health: the Official Journal of the American Telemedicine Association
https://www.readbyqxmd.com/read/28769817/suicidal-ideation-is-associated-with-altered-variability-of-fingertip-photo-plethysmogram-signal-in-depressed-patients
#5
Ahsan H Khandoker, Veena Luthra, Yousef Abouallaban, Simanto Saha, Khawza I U Ahmed, Raqibul Mostafa, Nayeefa Chowdhury, Herbert F Jelinek
Physiological and psychological underpinnings of suicidal behavior remain ill-defined and lessen timely diagnostic identification of this subgroup of patients. Arterial stiffness is associated with autonomic dysregulation and may be linked to major depressive disorder (MDD). The aim of this study was to investigate the association between arterial stiffness by photo-plethysmogram (PPG) in MDD with and without suicidal ideation (SI) by applying multiscale tone entropy (T-E) variability analysis. Sixty-one 10-min PPG recordings were analyzed from 29 control, 16 MDD patients with (MDDSI+) and 16 patients without SI (MDDSI-)...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28764344/time-domain-simulation-of-gd-3-gd-3-distance-measurements-by-epr
#6
Nurit Manukovsky, Akiva Feintuch, Ilya Kuprov, Daniella Goldfarb
Gd(3+)-based spin labels are useful as an alternative to nitroxides for intramolecular distance measurements at high fields in biological systems. However, double electron-electron resonance (DEER) measurements using model Gd(3+) complexes featured a low modulation depth and an unexpected broadening of the distance distribution for short Gd(3+)-Gd(3+) distances, when analysed using the software designed for S = 1/2 pairs. It appears that these effects result from the different spectroscopic characteristics of Gd(3+)-the high spin, the zero field splitting (ZFS), and the flip-flop terms in the dipolar Hamiltonian that are often ignored for spin-1/2 systems...
July 28, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28751867/defects-in-vascular-mechanics-due-to-aging-in-rats-studies-on-arterial-wave-properties-from-a-single-aortic-pressure-pulse
#7
Chun-Yi Chang, Ru-Wen Chang, Shu-Hsien Hsu, Ming-Shiou Wu, Ya-Jung Cheng, Hsien-Li Kao, Liang-Chuan Lai, Chih-Hsien Wang, Kuo-Chu Chang
Changes in vascular mechanics due to aging include elevated vascular impedance, diminished aorta distensibility, and an accelerated return of pulse wave reflection, which may increase the systolic workload on the heart. Classically, the accurate measurement of vascular mechanics requires the simultaneous recording of aortic pressure and flow signals. In practice, it is feasible to estimate arterial wave properties in terms of wave transit time (τw) and wave reflection index (RI) by using aortic pressure signal alone...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28751648/effects-of-ultrashort-laser-pulses-on-angular-distributions-of-photoionization-spectra
#8
C H Raymond Ooi, W L Ho, A D Bandrauk
We study the photoelectron spectra by intense laser pulses with arbitrary time dependence and phase within the Keldysh framework. An efficient semianalytical approach using analytical transition matrix elements for hydrogenic atoms in any initial state enables efficient and accurate computation of the photoionization probability at any observation point without saddle point approximation, providing comprehensive three dimensional photoelectron angular distribution for linear and elliptical polarizations, that reveal the intricate features and provide insights on the photoionization characteristics such as angular dispersions, shift and splitting of photoelectron peaks from the tunneling or above threshold ionization(ATI) regime to non-adiabatic(intermediate) and multiphoton ionization(MPI) regimes...
July 27, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28748207/ultrasound-data-for-laboratory-calibration-of-an-analytical-model-to-calculate-crack-depth-on-asphalt-pavements
#9
Miguel A Franesqui, Jorge Yepes, Cándida García-González
This article outlines the ultrasound data employed to calibrate in the laboratory an analytical model that permits the calculation of the depth of partial-depth surface-initiated cracks on bituminous pavements using this non-destructive technique. This initial calibration is required so that the model provides sufficient precision during practical application. The ultrasonic pulse transit times were measured on beam samples of different asphalt mixtures (semi-dense asphalt concrete AC-S; asphalt concrete for very thin layers BBTM; and porous asphalt PA)...
August 2017: Data in Brief
https://www.readbyqxmd.com/read/28706235/temporal-profiles-for-measuring-threshold-of-random-lasers-pumped-by-ns-pulses
#10
Xiaoyu Shi, Qing Chang, Junhua Tong, Yunjie Feng, Zhaona Wang, Dahe Liu
The working threshold is an important parameter to assess the performance of cavity-free random lasers. Here, the temporal profile measurement is proposed as an alternative method to determine the thresholds of the surface plasmon based random lasers pumped by ns pulses based on analyzing the delay time (t Delay) and rising time (t R) of the emission signal. The obvious and slight inflection points of the curves of t Delay and t R varying with the pump power density are observed as indicators for the thresholds of random lasing and for the transition of lasing mode, respectively...
July 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28699041/pulse-rate-and-transit-time-analysis-to-predict-hypotension-events-after-spinal-anesthesia-during-programmed-cesarean-labor
#11
Juan Bolea, Jesús Lázaro, Eduardo Gil, Eva Rovira, José M Remartínez, Pablo Laguna, Esther Pueyo, Augusto Navarro, Raquel Bailón
Prophylactic treatment has been proved to reduce hypotension incidence after spinal anesthesia during cesarean labor. However, the use of pharmacological prophylaxis could carry out undesirable side-effects on mother and fetus. Thus, the prediction of hypotension becomes an important challenge. Hypotension events are hypothesized to be related to a malfunctioning of autonomic nervous system (ANS) regulation of blood pressure. In this work, ANS responses to positional changes of 51 pregnant women programmed for a cesarean labor were explored for hypotension prediction...
July 11, 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/28692278/ab-initio-calculations-of-ultrashort-carrier-dynamics-in-two-dimensional-materials-valley-depolarization-in-single-layer-wse2
#12
Alejandro Molina-Sánchez, Davide Sangalli, Ludger Wirtz, Andrea Marini
In single-layer WSe2, a paradigmatic semiconducting transition metal dichalcogenide, a circularly polarized laser field can selectively excite electronic transitions in one of the inequivalent K(±) valleys. Such selective valley population corresponds to a pseudospin polarization. This can be used as a degree of freedom in a "valleytronic" device provided that the time scale for its depolarization is sufficiently large. Yet, the mechanism behind the valley depolarization still remains heavily debated. Recent time-dependent Kerr experiments have provided an accurate way to visualize the valley dynamics by measuring the rotation of a linearly polarized probe pulse applied after a circularly polarized pump pulse...
July 14, 2017: Nano Letters
https://www.readbyqxmd.com/read/28688430/imaging-of-rotational-wave-function-in-photodissociation-of-rovibrationally-excited-hcl-molecules
#13
K Grygoryeva, J Rakovský, O Votava, M Fárník
We demonstrate a visualization of quantum mechanical phenomena with the velocity map imaging (VMI) technique, combining vibrationally mediated photodissociation (VMP) of a simple diatomic HCl with the VMI of its H-photofragments. Free HCl molecules were excited by a pump infrared (IR) laser pulse to particular rotational J levels of the v = 2 vibrational state, and subsequently a probe ultraviolet laser photodissociated the molecule at a fixed wavelength of 243.07 nm where also the H-fragments were ionized...
July 7, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28680055/panoramic-reconstruction-temporal-imaging-for-seamless-measurements-of-slowly-evolved-femtosecond-pulse-dynamics
#14
Bowen Li, Shu-Wei Huang, Yongnan Li, Chee Wei Wong, Kenneth K Y Wong
Single-shot real-time characterization of optical waveforms with sub-picosecond resolution is essential for investigating various ultrafast optical dynamics. However, the finite temporal recording length of current techniques hinders comprehensive understanding of many intriguing ultrafast optical phenomena that evolve over a timescale much longer than their fine temporal details. Inspired by the space-time duality and by stitching of multiple microscopic images to achieve a larger field of view in the spatial domain, here a panoramic-reconstruction temporal imaging (PARTI) system is devised to scale up the temporal recording length without sacrificing the resolution...
July 5, 2017: Nature Communications
https://www.readbyqxmd.com/read/28671576/hybrid-optical-unobtrusive-blood-pressure-measurements
#15
Guangfei Zhang, Caifeng Shan, Ihor Kirenko, Xi Long, Ronald M Aarts
Blood pressure (BP) is critical in diagnosing certain cardiovascular diseases such as hypertension. Some previous studies have proved that BP can be estimated by pulse transit time (PTT) calculated by a pair of photoplethysmography (PPG) signals at two body sites. Currently, contact PPG (cPPG) and imaging PPG (iPPG) are two feasible ways to obtain PPG signals. In this study, we proposed a hybrid system (called the ICPPG system) employing both methods that can be implemented on a wearable device, facilitating the measurement of BP in an inconspicuous way...
July 1, 2017: Sensors
https://www.readbyqxmd.com/read/28668046/model-of-ultrafast-demagnetization-driven-by-spin-orbit-coupling-in-a-photoexcited-antiferromagnetic-insulator-cr2o3
#16
Feng Guo, Na Zhang, Wei Jin, Jun Chang
We theoretically study the dynamic time evolution following laser pulse pumping in an antiferromagnetic insulator Cr2O3. From the photoexcited high-spin quartet states to the long-lived low-spin doublet states, the ultrafast demagnetization processes are investigated by solving the dissipative Schrödinger equation. We find that the demagnetization times are of the order of hundreds of femtoseconds, in good agreement with recent experiments. The switching times could be strongly reduced by properly tuning the energy gaps between the multiplet energy levels of Cr(3+)...
June 28, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28665647/multiple-quantum-transitions-and-charge-induced-decoherence-of-donor-nuclear-spins-in-silicon
#17
David P Franke, Moritz P D Pflüger, Kohei M Itoh, Martin S Brandt
We study single- and multiquantum transitions of the nuclear spins of an ensemble of ionized arsenic donors in silicon and find quadrupolar effects on the coherence times, which we link to fluctuating electrical field gradients present after the application of light and bias voltage pulses. To determine the coherence times of superpositions of all orders in the 4-dimensional Hilbert space, we use a phase-cycling technique and find that, when electrical effects were allowed to decay, these times scale as expected for a fieldlike decoherence mechanism such as the interaction with surrounding ^{29}Si nuclear spins...
June 16, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28662412/correlation-between-deposition-parameters-of-periodic-titanium-metal-oxide-nanometric-multilayers-and-their-chemical-and-structural-properties-investigated-by-stem-eels
#18
Valérie Potin, Arnaud Cacucci, Nicolas Martin
We analyze structure and composition of titanium-based metal/oxide periodic multilayers prepared by reactive sputtering. The reactive gas pulsing process is involved to periodically inject the oxygen gas during the multilayers deposition. This approach allows the growth of regular and tunable nanometric TiO2/Ti periods with thicknesses ranging from 14 to 50nm. The interfacial layer between oxide and metallic layers is mainly the fcc-TiO phase as clearly pointed out by transmission electron microscopy and associated electron spectroscopies...
June 21, 2017: Micron: the International Research and Review Journal for Microscopy
https://www.readbyqxmd.com/read/28656499/electrical-properties-of-polyetherimide-thin-films-non-parametric-dielectric-response-analysis-with-distribution-of-relaxation-times
#19
Enis Tuncer
High temperature polymeric materials for electrical insulation and energy storage are needed for transformational power applications such as pulsed-power and hybrid electrical vehicles. One of the candidate materials has been polyetherimide, an amorphous thermoplastic with a glass transition over 200 (°)C. Here, the dielectric studies on the material are reported by taking into account the polarization and conduction processes in the polyetherimide. The dielectric data were analyzed with the distribution of relaxation times approach with Debye expression as the kernel in the inversion algorithm, the results then created the relaxation map for polyetherimide...
June 2017: European Physical Journal. E, Soft Matter
https://www.readbyqxmd.com/read/28639945/pulmonary-arterial-hemodynamic-assessment-by-a-novel-index-in-systemic-lupus-erythematosus-patients-pulmonary-pulse-transit-time
#20
Tolga Han Efe, Mehmet Doğan, Cem Özişler, Tolga Çimen, Mehmet Ali Felekoğlu, Ahmet Göktuğ Ertem, Engin Algül, Sadık Açıkel
OBJECTIVE: Systemic lupus erythematosus (SLE) is a chronic, inflammatory, and autoimmune connective tissue disease. One of the leading causes of mortality among SLE patients is pulmonary hypertension. The aim of this study was to evaluate the association between echocardiographic findings, including the pulmonary pulse transit time and pulmonary hypertension parameters, in SLE patients. METHODS: Thirty SLE patients (aged 39.9±11 years, 28 females) as the study group and 34 age- and sex-matched healthy volunteers (aged 37...
June 22, 2017: Anatolian Journal of Cardiology
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