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https://www.readbyqxmd.com/read/28237937/investigation-of-viscoelasticity-in-the-relationship-between-carotid-artery-blood-pressure-and-distal-pulse-volume-waveforms
#1
Jong Chan Lee, Zahra Ghasemi, Chang-Sei Kim, Hao-Min Cheng, Chen-Huan Chen, Shih-Hsien Sung, Ramakrishna Mukkamala, Jin-Oh Hahn
We investigated the relationship between carotid artery blood pressure (BP) and distal pulse volume waveforms (PVRs) via subject-specific mathematical modeling. We conceived three physical models to define the relationship: a tube-load model augmented with a gain (TLG), Voigt (TLV) and standard linear solid (TLS) models. We compared these models using PVRs measured via BP cuffs at an upper arm and an ankle as well as carotid artery tonometry waveform collected from 133 subjects. At both upper arm and ankle, PVR was related to carotid artery tonometry by TLV and TLS models better than by TLG model; when root-mean-squared over all the subjects, the systolic and diastolic BP errors between measured carotid artery tonometry waveform and the one estimated from distal PVR reduced from 4...
February 22, 2017: IEEE Journal of Biomedical and Health Informatics
https://www.readbyqxmd.com/read/28237324/in%C3%A2-vitro-production-of-embryos-using-immature-oocytes-collected-transvaginally-from-superstimulated-wood-bison-bison-bison-athabascae
#2
Miriam P Cervantes, J Manuel Palomino, Muhammad Anzar, Reuben J Mapletoft, Gabriela F Mastromonaco, Gregg P Adams
Two experiments were done to test the hypothesis that morphologic characteristics of wood bison cumulus-oocyte complexes (COC) are reflective of the ability of the oocyte to develop to an advanced embryonic stage after in vitro maturation, fertilization and culture, and to determine the effect of prolonging the interval from the end of superstimulation treatment to oocyte collection (FSH starvation period). Experiments were done during the anovulatory season. In Experiment 1, ovarian superstimulation was induced in 10 bison with two doses of FSH given at 48 h intervals beginning at the time of follicular wave emergence...
April 1, 2017: Theriogenology
https://www.readbyqxmd.com/read/28237125/biomarkers-of-atrial-cardiopathy-and-atrial-fibrillation-detection-on-mobile-outpatient-continuous-telemetry-after-embolic-stroke-of-undetermined-source
#3
Denise Sebasigari, Alexander Merkler, Yang Guo, Gino Gialdini, Benjamin Kummer, Morgan Hemendinger, Christopher Song, Antony Chu, Shawna Cutting, Brian Silver, Mitchell S V Elkind, Hooman Kamel, Karen L Furie, Shadi Yaghi
BACKGROUND: Biomarkers of atrial dysfunction or "cardiopathy" are associated with embolic stroke risk. However, it is unclear if this risk is mediated by undiagnosed paroxysmal atrial fibrillation or flutter (AF). We aim to determine whether atrial cardiopathy biomarkers predict AF on continuous heart-rhythm monitoring after embolic stroke of undetermined source (ESUS). METHODS: This was a single-center retrospective study including all patients with ESUS undergoing 30 days of ambulatory heart-rhythm monitoring to look for AF between January 1, 2013 and December 31, 2015...
February 22, 2017: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
https://www.readbyqxmd.com/read/28231476/evaluation-of-cognitive-performance-in-professional-divers-by-means-of-event-related-potentials-and-neuropsychology
#4
Mehmet Ergen, Atilla Uslu, Ozlem Caglar, Sukriye Akca-Kalem, Maide Cimsit, Hakan Gurvit
OBJECTIVE: We investigated whether professional air diving with no decompression illness causes any long-term changes in cognitive functions. METHODS: The all-male participants consisted of 18 healthy control (HC) volunteers and 32 divers. Divers were divided into two subgroups as moderate exposure group, Divers-I (DI) and extensive exposure group, Divers-II (DII). Participants were administered a comprehensive neuropsychological battery and event-related potentials (ERPs) were recorded while they performed auditory oddball task and visual continuous performance test (CPT)...
January 29, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/28231259/impact-of-seasonality-and-air-pollutants-on-carotid-femoral-pulse-wave-velocity-and-wave-reflection-in-hypertensive-patients
#5
Marina Di Pilla, Rosa Maria Bruno, Francesco Stea, Luciano Massetti, Stefano Taddei, Lorenzo Ghiadoni, Pietro Amedeo Modesti
OBJECTIVE: The effects of seasonality on blood pressure (BP) and cardiovascular (CV) events are well established, while the influence of seasonality and other environmental factors on arterial stiffness and wave reflection has never been analyzed. This study evaluated whether seasonality (daily number of hours of light) and acute variations in outdoor temperature and air pollutants may affect carotid-femoral pulse wave velocity (PWV) and pressure augmentation. DESIGN AND METHOD: 731 hypertensive patients (30-88 years, 417 treated) were enrolled in a cross-sectional study during a 5-year period...
2017: PloS One
https://www.readbyqxmd.com/read/28230869/a-combined-high-temperature-experimental-and-theoretical-kinetic-study-of-the-reaction-of-dimethyl-carbonate-with-oh-radicals
#6
Fethi Khaled, Binod Raj Giri, Milán Szőri, Tam V-T Mai, Lam K Huynh, Aamir Farooq
The reaction kinetics of dimethyl carbonate (DMC) and OH radicals were investigated behind reflected shock waves over the temperature range of 872-1295 K and at pressures near 1.5 atm. Reaction progress was monitored by detecting OH radicals at 306.69 nm using a UV laser absorption technique. The rate coefficients for the reaction of DMC with OH radicals were extracted using a detailed kinetic model developed by Glaude et al. (Proc. Combust. Inst. 2005, 30(1), 1111-1118). The experimental rate coefficients can be expressed in Arrhenius form as: kexpt'l = 5...
February 23, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28229053/large-artery-stiffness-assessment-using-sphygmocor-technology
#7
REVIEW
Mark Butlin, Ahmad Qasem
Large artery stiffness assessment has been an integral part of the SphygmoCor technology since 1998. Aortic stiffness is approximated with non-invasive measurement of carotid-femoral pulse wave velocity, with improvements made with time to make the assessment procedure quicker and more user independent. Also standard in the devices is the ability to reliably calculate the central aortic waveform shape from a peripheral pressure waveform from either the brachial or radial artery. This waveform contains much information beyond peak and trough (systolic and diastolic pressure)...
January 2017: Pulse (Basel, Switzerland)
https://www.readbyqxmd.com/read/28227995/comparison-of-pulse-wave-velocity-derived-from-accelerometer-and-reflective-photo-plethysmography-signals-placed-at-the-carotid-and-femoral-artery
#8
Jens Muehlsteff, Erik Bresch, Lars Schmitt, Jos Gelissen, Peter Bingley, Jens Muehlsteff, Erik Bresch, Lars Schmitt, Jos Gelissen, Peter Bingley, Jos Gelissen, Peter Bingley, Lars Schmitt, Jens Muehlsteff, Erik Bresch
Carotid - femoral pulse wave velocity is an established measure to assess cardiovascular risk and an interesting surrogate parameter towards non-invasive continuous blood pressure inference. Due to progress in sensing technologies for wearable wrist worn sensors, there are low cost sensor combinations of photo-plethysmography and high fidelity accelerometers available offering access to pulse information from larger arteries complemented by blood volume changes in the superficial tissue. In this work we compare pulse wave velocities derived from accelerometer and reflective photo-plethysmography signals placed at the carotid and femoral artery...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227281/modeling-digital-pulse-waveforms-by-solving-one-dimensional-navier-stokes-equations
#9
Aleksandr A Fedotov, Anna S Akulova, Sergey A Akulov, Aleksandr A Fedotov, Anna S Akulova, Sergey A Akulov, Aleksandr A Fedotov, Anna S Akulova, Sergey A Akulov
Mathematical modeling for composition distal arterial pulse wave in the blood vessels of the upper limbs was considered. Formation of distal arterial pulse wave is represented as a composition of forward and reflected pulse waves propagating along the arterial vessels. The formal analogy between pulse waves propagation along the human arterial system and the propagation of electrical oscillations in electrical transmission lines with distributed parameters was proposed. Dependencies of pulse wave propagation along the human arterial system were obtained by solving the one-dimensional Navier-Stokes equations for a few special cases...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227251/robust-extraction-of-the-n1-effect-in-dichotic-listening-using-hardy-space-mappings-of-auditory-late-single-trials
#10
Farah I Corona-Strauss, Daniel J Strauss, Farah I Corona-Strauss, Daniel J Strauss, Farah I Corona-Strauss, Daniel J Strauss
It is known that signs of (early) auditory selective attention are reflected in the N1-wave of auditory late potentials. In recent years, we have analyzed this N1-effect using multiscale neurofunctional modeling and (instantaneous) phase synchronization measures of Hardy space mapped data. To acquire the electroencephalographic data in dichotic listening, we repeated the seminal experiment of Hillyard et al. which first described the N1-effect. Here we apply for the first time phase synchronization measures to these dichotic data and compare the results to the conventional time-domain analysis...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227128/boundary-element-simulation-of-ultrasonic-backscattering-during-the-fracture-healing-process
#11
Vassiliki T Potsika, Konstantinos N Grivas, Theodoras Gortsas, Vasilios C Protopappas, Demosthenes K Polyzos, Dimitrios I Fotiadis, Vassiliki T Potsika, Konstantinos N Grivas, Theodoras Gortsas, Vasilios C Protopappas, Demosthenes K Polyzos, Dimitrios I Fotiadis, Dimitrios I Fotiadis, Theodoros Gortsas, Vasilios C Protopappas, Vassiliki T Potsika, Konstantinos N Grivas, Demosthenes K Polyzos
Competent fracture healing monitoring and treatment requires an extensive knowledge of bone biology and microstructure. The use of non-invasive and non-radiating means for the monitoring of the bone healing process has gained significant interest in recent years. Ultrasound is considered as a modality which can contribute to the assessment of bone status during the healing process, as well as, enhance the rate of the tissues' ossification. This work presents boundary element simulations of ultrasound propagation in healing long bones to investigate the monitoring potential of backscattering parameters...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227000/missing-rri-interpolation-for-hrv-analysis-using-locally-weighted-partial-least-squares-regression
#12
Keisuke Kamata, Koichi Fujiwara, Toshiki Yamakawa, Manabu Kano, Keisuke Kamata, Koichi Fujiwara, Toshiki Yamakawa, Manabu Kano
The R-R interval (RRI) fluctuation in electrocardiogram (ECG) is called heart rate variability (HRV). Since HRV reflects autonomic nervous function, HRV-based health monitoring services, such as stress estimation, drowsy driving detection, and epileptic seizure prediction, have been proposed. In these HRV-based health monitoring services, precise R wave detection from ECG is required; however, R waves cannot always be detected due to ECG artifacts. Missing RRI data should be interpolated appropriately for HRV analysis...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226925/human-physical-condition-rf-sensing-at-thz-range
#13
A Vorobyov, E Daskalaki, C Hennemann, J-D Decotignie, A Vorobyov, E Daskalaki, C Hennemann, J-D Decotignie, E Daskalaki, C Hennemann, A Vorobyov, J-D Decotignie
The skin response to high radio frequency has been associated with the human physical condition and most prominently with the stress. The objective of this study is to investigate the possibility to detect mental and light physical stress through the measurement of skin reflectance in the mm-wave/sub-THz band. Two frequency bands have been considered, 75-110 GHz (Band-I) and 325-500 GHz (Band-II), while the measurements have been performed in the three different locations, the arm, the dorsal side of the hand and the fingertip...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226821/cortical-auditory-evoked-potentials-caeps-represent-neural-cues-relevant-to-pitch-perception
#14
Xiaochen Zhang, Qin Gong, Tao Zhang, Xiaochen Zhang, Qin Gong, Tao Zhang, Xiaochen Zhang, Tao Zhang, Qin Gong
Components of auditory event-related potentials (ERPs) may represent various aspects of the cortical processing of pitch. However, evidence hints an earlier representation of pitch perception in auditory ERPs of cortical origin. In this study, we examined whether earlier waves in cortical auditory evoked potentials (CAEPs) might reflect pitch-relevant features of both listeners and stimuli. CAEPs were elicited by pure tones and sweeping tones, and individual behavioral performance in pitch discrimination reflected by frequency difference limen (FDL) was also measured...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28225481/the-dysfunction-of-inhibition-control-in-pituitary-patients-evidence-from-the-go-nogo-event-related-potential-study
#15
Chenglong Cao, Jian Song, Shun Yao, Yan Yan, Shun Li, Guibao Peng, Pan Ma, Hao Du, Cheng Huang, Huichao Ding, Yuanzhi He, Ronghui Sun, Guozheng Xu
Pituitary tumor is an intracranial tumor; because of the development of neuroimaging technology in recent years, morbidity is likely to increase. Evidence showed impaired cognitive ability of patients with pituitary adenoma. There is evidence that neurobehavioral disorders are common in pituitary adenoma patients. This disorder is because of the cognitive and emotional function of the important functional areas of the brain oppressed and hormone imbalance. Individuals' mental activity is controlled by the brain and the abnormal mental activity is caused by both the structural abnormalities of the brain and neurochemical dysfunction...
February 20, 2017: Neuroreport
https://www.readbyqxmd.com/read/28221714/photonic-devices-out-of-equilibrium-transient-memory-signal-propagation-and-sensing
#16
Thomas Heuser, Rémi Merindol, Sebastian Loescher, Aileen Klaus, Andreas Walther
Soft photonic materials are important for sensors, displays, or energy management and have become switchable under static equilibrium conditions by integration of responsive polymer features. The next step is to equip such materials with the ability for autonomously dynamic and self-regulating behavior, which would advance their functionality and application possibilities to new levels. Here, this study shows the system integration of a nonlinear, biocatalytic pH-feedback system with a pH-responsive block copolymer photonic gel, and demonstrates autonomous transient memories, remotely controlled signal propagation, and sensing...
February 21, 2017: Advanced Materials
https://www.readbyqxmd.com/read/28220861/electrically-tunable-metasurface-based-on-mie-type-dielectric-resonators
#17
Zhaoxian Su, Qian Zhao, Kun Song, Xiaopeng Zhao, Jianbo Yin
In this paper, we have designed a metasurface based on electrically tunable Mie-type resonators and theoretically demonstrated its tunable response to electromagnetic waves with varying frequency. The metasurface consists of disk-like ferroelectric resonators arrayed on a metal film and the upper surface of resonators is covered by ion gel film which is transparent for incident electromagnetic wave. Using the metal film and ion gel film as electrodes, the permittivity of the resonators can be adjusted by an external electric field and, as a result, the reflection phase of the resonators can be dynamically adjusted in a relatively wide range...
February 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28219917/isosorbide-dinitrate-with-or-without-hydralazine-does-not-reduce-wave-reflections-left-ventricular-hypertrophy-or-myocardial-fibrosis-in-patients-with-heart-failure-with-preserved-ejection-fraction
#18
Payman Zamani, Scott Akers, Haideliza Soto-Calderon, Melissa Beraun, Maheswara R Koppula, Swapna Varakantam, Deepa Rawat, Prithvi Shiva-Kumar, Philip G Haines, Jesse Chittams, Raymond R Townsend, Walter R Witschey, Patrick Segers, Julio A Chirinos
BACKGROUND: Wave reflections, which are increased in patients with heart failure with preserved ejection fraction, impair diastolic function and promote pathologic myocardial remodeling. Organic nitrates reduce wave reflections acutely, but whether this is sustained chronically or affected by hydralazine coadministration is unknown. METHODS AND RESULTS: We randomized 44 patients with heart failure with preserved ejection fraction in a double-blinded fashion to isosorbide dinitrate (ISDN; n=13), ISDN+hydralazine (ISDN+hydral; n=15), or placebo (n=16) for 6 months...
February 20, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/28215751/rewriting-age-to-overcome-misaligned-age-and-gender-norms-in-later-life
#19
Jeremiah C Morelock, Jeffrey E Stokes, Sara M Moorman
In this paper we suggest that older adults undergo a misalignment between societal age norms and personal lived experience, and attempt reconciliation through discursive strategies: They rewrite how they frame chronological age as well as their subjective relations to it. Using a sample of 4041 midlife and older adults from the 2004-2006 wave of the National Survey of Midlife Development in the United States (MIDUS II), we explore associations of age and gender with subjective age and at what age respondents felt people enter later life...
January 2017: Journal of Aging Studies
https://www.readbyqxmd.com/read/28213868/elliptical-fourier-analysis-fundamentals-applications-and-value-for-forensic-anthropology
#20
REVIEW
Jodi Caple, John Byrd, Carl N Stephan
The numerical description of skeletal morphology enables forensic anthropologists to conduct objective, reproducible, and structured tests, with the added capability of verifying morphoscopic-based analyses. One technique that permits comprehensive quantification of outline shape is elliptical Fourier analysis. This curve fitting technique allows a form's outline to be approximated via the sum of multiple sine and cosine waves, permitting the profile perimeter of an object to be described in a dense (continuous) manner at a user-defined level of precision...
February 17, 2017: International Journal of Legal Medicine
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