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https://www.readbyqxmd.com/read/28339777/support-system-for-fine-focusing-and-astigmatism-correction-using-an-auditory-signal-in-scanning-electron-microscopy
#1
Eisaku Oho, Kazuhiko Suzuki, Sadao Yamazaki
The current study describes a new support system for fine focusing and near-perfect astigmatism correction for scanning electron microscopy (SEM). The signal-to-noise ratio of a series of SEM images obtained from fast scan rates (TV scan) was adopted as a new metric for evaluating focus. Measured signal-to-noise ratio values were converted to an acoustic signal (sound wave frequency) using digital image processing techniques, enabling the SEM user to evaluate image focus using the auditory modality. Accurate focusing and correcting astigmatism in general-purpose SEM is traditionally time-consuming and difficult...
February 24, 2017: Microscopy
https://www.readbyqxmd.com/read/28339776/effect-of-acute-millimeter-wave-exposure-on-dopamine-metabolism-of-ngf-treated-pc12-cells
#2
Alexis J Haas, Yann Le Page, Maxim Zhadobov, Ronan Sauleau, Yves Le Dréan, Christian Saligaut
Several forthcoming wireless telecommunication systems will use electromagnetic frequencies at millimeter waves (MMWs), and technologies developed around the 60-GHz band will soon know a widespread distribution. Free nerve endings within the skin have been suggested to be the targets of MMW therapy which has been used in the former Soviet Union. So far, no studies have assessed the impact of MMW exposure on neuronal metabolism. Here, we investigated the effects of a 24-h MMW exposure at 60.4 GHz, with an incident power density (IPD) of 5 mW/cm², on the dopaminergic turnover of NGF-treated PC12 cells...
February 24, 2017: Journal of Radiation Research
https://www.readbyqxmd.com/read/28339545/left-atrial-anatomy-atrial-fibrillation-burden-and-p-wave-duration-relationships-and-predictors-for-single-procedure-success-after-pulmonary-vein-isolation
#3
Sven Knecht, Maurice Pradella, Tobias Reichlin, Aline Mühl, Matthias Bossard, Bram Stieltjes, David Conen, Jens Bremerich, Stefan Osswald, Michael Kühne, Christian Sticherling
Aims: Atrial fibrillation (AF) is associated with changes in left atrial (LA) volume, but the relationship between LA size, AF burden, and electrical conduction behaviour is still uncertain. The aim of this study was to quantify the association and impact of these parameters on the single-procedure outcome after circumferential antral ablation for pulmonary vein isolation. Methods and results: Left atrial assessment was performed in 129 consecutive patients using pre-procedural imaging in three dimensions (sphericity, indexed volume), two dimensions (diameters), and from echocardiography in one dimension (long axis)...
December 22, 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28333623/a-comparison-of-fem-based-inversion-algorithms-local-frequency-estimation-and-direct-inversion-approach-used-in-mr-elastography
#4
Mohammad Honarvar, Ramin Sahebjavaher, Robert Rohling, Septimiu Salcudean
In quantitative elastography, maps of the mechanical properties of soft tissue, or elastograms, are calculated from the measured displacement data by solving an inverse problem. The model assumptions have a significant effect on elastograms. Motivated by the high sensitivity of imaging results to the model assumptions for in-vivo Magnetic Resonance Elastography (MRE) of the prostate, we compared elastograms obtained with four different methods. Two FEM-based methods developed by our group were compared with two other commonly used methods, Local Frequency Estimator (LFE) and curl-based Direct Inversion (c-DI)...
March 22, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28332042/the-effect-of-wi-fi-electromagnetic-waves-in-unimodal-and-multimodal-object-recognition-tasks-in-male-rats
#5
Amin Hassanshahi, Seyed Ali Shafeie, Iman Fatemi, Elham Hassanshahi, Mohammad Allahtavakoli, Mohammad Shabani, Ali Roohbakhsh, Ali Shamsizadeh
Wireless internet (Wi-Fi) electromagnetic waves (2.45 GHz) have widespread usage almost everywhere, especially in our homes. Considering the recent reports about some hazardous effects of Wi-Fi signals on the nervous system, this study aimed to investigate the effect of 2.4 GHz Wi-Fi radiation on multisensory integration in rats. This experimental study was done on 80 male Wistar rats that were allocated into exposure and sham groups. Wi-Fi exposure to 2.4 GHz microwaves [in Service Set Identifier mode (23...
March 22, 2017: Neurological Sciences
https://www.readbyqxmd.com/read/28331254/an-investigation-to-identify-potential-risk-factors-associated-with-common-chronic-diseases-among-the-older-population-in-india
#6
Enemona Emmanuel Adaji, Anand S Ahankari, Puja R Myles
BACKGROUND: In India, chronic diseases are the leading cause of death and their prevalence has constantly increased over the last decade. OBJECTIVE: This study aimed to identify risk factors associated with common chronic diseases among people aged 50 years and over in India. MATERIALS AND METHODS: Data from Wave 1 of the 2007/2008 Indian Study on Global Ageing and Adult Health (SAGE) was used to investigate the association between lifestyle choices and chronic diseases using logistic regression...
January 2017: Indian Journal of Community Medicine
https://www.readbyqxmd.com/read/28330820/analysis-of-the-association-between-electrocardiographic-p-wave-characteristics-and-atrial-fibrillation-in-the-regicor-study
#7
Albert Massó-van Roessel, Luis Alberto Escobar-Robledo, Irene R Dégano, María Grau, Joan Sala, Rafel Ramos, Jaume Marrugat, Antoni Bayés de Luna, Roberto Elosua
INTRODUCTION AND OBJECTIVES: Atrial fibrillation (AF) is the most common clinically significant cardiac arrhythmia. P-wave duration and interatrial blocks (IAB) have been reported to be associated with AF. Our aim was to determine the individual and combined association of P-wave duration and advanced IAB morphology with AF. METHODS: We designed an age-, sex-, and survey-matched case-control study nested in a population-based cohort (REGICOR: REgistre GIroní del COR)...
March 18, 2017: Revista Española de Cardiología
https://www.readbyqxmd.com/read/28330682/the-impact-of-posture-on-the-cardiac-depolarization-and-repolarization-phases-of-the-qt-interval-in-healthy-subjects
#8
Yurie Obata, Pavel Ruzankin, Qi Jia Ong, Dan E Berkowitz, Ronald D Berger, Jochen Steppan, Viachaslau Barodka
BACKGROUND: Postural changes affect both heart rate and the QT interval. OBJECTIVE: To investigate the effects of postural changes on the depolarization and repolarization phases of the QT interval. METHODS: A three lead ECG from 12 healthy young volunteers was recorded in the standing, sitting and in the supine positions. For the purpose of this study, we defined the depolarization phase as the QRS complex plus the ST segment and the repolarization phase as the duration of the T wave...
March 12, 2017: Journal of Electrocardiology
https://www.readbyqxmd.com/read/28330663/longitudinal-changes-in-lv-structure-and-diastolic-function-in-relation-to-arterial-properties-in-general%C3%A2-population
#9
Nicholas Cauwenberghs, Judita Knez, Jan D'hooge, Lutgarde Thijs, Wen-Yi Yang, Fang-Fei Wei, Zhen-Yu Zhang, Jan A Staessen, Tatiana Kuznetsova
OBJECTIVES: We assessed to what extent arterial properties measured at baseline and follow-up predict longitudinal alterations in echocardiographic indexes reflecting left ventricular (LV) structure and function. BACKGROUND: Serial imaging studies are needed to clarify the relation of changes in LV structure and function to arterial stiffness. METHODS: In 607 participants (50.7% women; mean age 50.7 years), using echocardiography and Doppler imaging, we measured LV dimensions, transmitral blood flow, and mitral annular tissue velocities at baseline and after 4...
March 10, 2017: JACC. Cardiovascular Imaging
https://www.readbyqxmd.com/read/28327465/anomalous-rashba-spin-orbit-interaction-in-electrically-controlled-topological-insulator-based-on-inn-gan-quantum-wells
#10
S P Lepkowski, Witold Bardyszewski
We study theoretically the topological phase transition and the Rashba spin-orbit interaction in electrically biased InN/GaN quantum wells. We show that that for properly chosen widths of quantum wells and barriers, one can effectively tune the system through the topological phase transition applying an external electric field perpendicular to the QW plane. We find that in InN/GaN quantum wells with the inverted band structure, when the conduction band s-type level is below the heavy hole and light hole p-type levels, the spin splitting of the subbands decreases with increasing the amplitude of the electric field in the quantum wells, which reveals the anomalous Rashba effect...
March 22, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/28325016/sleep-stage-classification-by-non-contact-vital-signs-indices-using-doppler-radar-sensors
#11
Masayuki Kagawa, Kazuki Suzumura, Takemi Matsui
Disturbed sleep has become more common in recent years. To improve the quality of sleep, undergoing sleep observation has gained interest as a means to resolve possible problems. In this paper, we evaluate a non-restrictive and non-contact method for classifying real-time sleep stages and report on its potential applications. The proposed system measures heart rate (HR), heart rate variability (HRV), body movements, and respiratory signals of a sleeping person using two 24-GHz microwave radars placed beneath the mattress...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324970/development-of-data-acquisition-components-for-simultaneous-recording-of-3d-epicardial-and-surface-ecg-signals-in-the-langendorff-perfusion-apparatus
#12
Ryan Wade Selby, Anup Jonchhe, Chen Kaplan, Coeli M Lopes, Behnaz Ghoraani
Sudden Cardiac Death (SCD) claims 7 million lives per year. The importance of myocardial electrogram (EGM) repolarization alternans and surface electrocardiogram (ECG) T-wave alternans is gaining traction for understanding the underlying SCD mechanisms. However, the relationship between the 3D spatial distribution of myocardial EGMs and surface ECG with respect to SCD has yet to be investigated. To make this happen, a modified data acquisition system has been developed and fabricated in conjunction with the Langendorff perfusion system to enable simultaneous recording and analysis of the 3D spatial distribution of myocardial EGMs and the surface ECG...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28321919/borderline-personality-disorder-and-regularly-drinking-alcohol-before-sex
#13
Ronald G Thompson, Nicholas R Eaton, Mei-Chen Hu, Deborah S Hasin
INTRODUCTION AND AIMS: Drinking alcohol before sex increases the likelihood of engaging in unprotected intercourse, having multiple sexual partners and becoming infected with sexually transmitted infections. Borderline personality disorder (BPD), a complex psychiatric disorder characterised by pervasive instability in emotional regulation, self-image, interpersonal relationships and impulse control, is associated with substance use disorders and sexual risk behaviours. However, no study has examined the relationship between BPD and drinking alcohol before sex in the USA...
March 20, 2017: Drug and Alcohol Review
https://www.readbyqxmd.com/read/28320658/compressed-sensing-based-synthetic-transmit-aperture-imaging-validation-in-a-convex-array-configuration
#14
Jing Liu, Qiong He, Jianwen Luo
According to the linear acoustic theory, the channel data of a plane wave emitted by a linear array is a linear combination of the full dataset of synthetic transmit aperture (STA). Combining this relationship with compressed sensing (CS), a novel CS based ultrasound beamforming strategy, named compressed sensing based synthetic transmit aperture (CS-STA), was previously proposed to increase the frame rate of ultrasound imaging without sacrificing the image quality for a linear array. In this paper, assuming linear transfer function of pulse-echo ultrasound system, we derived and applied the theory of CS-STA for a slightly curved array and validated CS-STA in a convex array configuration...
March 14, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28319401/using-sound-to-study-the-effect-of-frothers-on-the-break-away-of-air-bubbles-at-an-underwater-capillary
#15
Pengbo Chu, Randolph Pax, Ronghao Li, Ray Langlois, James Andrew Finch
Frothers, a class of surfactants, are widely employed in froth flotation to aid the generation of small bubbles. Their action is commonly explained by their ability to hinder coalescence. There are occasional references suggesting that frother may also play a role in the initial break-up of the injected air mass. This work investigates the possible effect of frother on break-up by monitoring air bubbles produced quasi-statically at an underwater capillary. Under this condition, break-up is isolated from coalescence, and an impact of frothers on the detached bubble can be ascribed to an impact on break-up...
March 20, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28317458/use-of-the-instantaneous-wave-free-ratio-or-fractional-flow-reserve-in-pci
#16
Justin E Davies, Sayan Sen, Hakim-Moulay Dehbi, Rasha Al-Lamee, Ricardo Petraco, Sukhjinder S Nijjer, Ravinay Bhindi, Sam J Lehman, Darren Walters, James Sapontis, Luc Janssens, Christiaan J Vrints, Ahmed Khashaba, Mika Laine, Eric Van Belle, Florian Krackhardt, Waldemar Bojara, Olaf Going, Tobias Härle, Ciro Indolfi, Giampaolo Niccoli, Flavo Ribichini, Nobuhiro Tanaka, Hiroyoshi Yokoi, Hiroaki Takashima, Yuetsu Kikuta, Andrejs Erglis, Hugo Vinhas, Pedro Canas Silva, Sérgio B Baptista, Ali Alghamdi, Farrel Hellig, Bon-Kwon Koo, Chang-Wook Nam, Eun-Seok Shin, Joon-Hyung Doh, Salvatore Brugaletta, Eduardo Alegria-Barrero, Martijin Meuwissen, Jan J Piek, Niels van Royen, Murat Sezer, Carlo Di Mario, Robert T Gerber, Iqbal S Malik, Andrew S P Sharp, Suneel Talwar, Kare Tang, Habib Samady, John Altman, Arnold H Seto, Jasvindar Singh, Allen Jeremias, Hitoshi Matsuo, Rajesh K Kharbanda, Manesh R Patel, Patrick Serruys, Javier Escaned
Background Coronary revascularization guided by fractional flow reserve (FFR) is associated with better patient outcomes after the procedure than revascularization guided by angiography alone. It is unknown whether the instantaneous wave-free ratio (iFR), an alternative measure that does not require the administration of adenosine, will offer benefits similar to those of FFR. Methods We randomly assigned 2492 patients with coronary artery disease, in a 1:1 ratio, to undergo either iFR-guided or FFR-guided coronary revascularization...
March 18, 2017: New England Journal of Medicine
https://www.readbyqxmd.com/read/28317438/instantaneous-wave-free-ratio-versus-fractional-flow-reserve-to-guide-pci
#17
Matthias Götberg, Evald H Christiansen, Ingibjörg J Gudmundsdottir, Lennart Sandhall, Mikael Danielewicz, Lars Jakobsen, Sven-Erik Olsson, Patrik Öhagen, Hans Olsson, Elmir Omerovic, Fredrik Calais, Pontus Lindroos, Michael Maeng, Tim Tödt, Dimitrios Venetsanos, Stefan K James, Amra Kåregren, Margareta Nilsson, Jörg Carlsson, Dario Hauer, Jens Jensen, Ann-Charlotte Karlsson, Georgios Panayi, David Erlinge, Ole Fröbert
Background The instantaneous wave-free ratio (iFR) is an index used to assess the severity of coronary-artery stenosis. The index has been tested against fractional flow reserve (FFR) in small trials, and the two measures have been found to have similar diagnostic accuracy. However, studies of clinical outcomes associated with the use of iFR are lacking. We aimed to evaluate whether iFR is noninferior to FFR with respect to the rate of subsequent major adverse cardiac events. Methods We conducted a multicenter, randomized, controlled, open-label clinical trial using the Swedish Coronary Angiography and Angioplasty Registry for enrollment...
March 18, 2017: New England Journal of Medicine
https://www.readbyqxmd.com/read/28317163/the-value-of-diastolic-flow-reversal-in-the-descending-thoracic-aorta-as-a-determinant-of-invasively-measured-aortic-pulse-pressure
#18
Hack-Lyoung Kim, Yu Nui Kim, Hee-Jun Kim, Woo-Hyun Lim, Jae-Bin Seo, Sang-Hyun Kim, Myung-A Kim, Joo-Hee Zo
AIM: Although the diastolic flow reversal of the descending aorta has been recognized in patients with aortic regurgitation, its generation without this condition is still unknown. This study was performed to investigate whether flow patterns of the descending thoracic aorta, as measured by echocardiography, can represent invasively measured aortic pulse pressure (APP). METHODS: A total of 100 patients (age, 62.3±11.0 years; men, 62.0%) undergoing invasive coronary angiography (ICA) was analyzed...
March 19, 2017: Echocardiography
https://www.readbyqxmd.com/read/28316113/the-utility-of-exercise-testing-in-risk-stratification-of-asymptomatic-patients-with-type-1-brugada-pattern
#19
Muthiah Subramanian, Mukund A Prabhu, M S Harikrishnan, Saritha S Shekhar, Praveen G Pai, K U Natarajan
INTRODUCTION: Risk stratification of asymptomatic patients with a Brugada type 1 ECG pattern remains an unresolved clinical conundrum. In contrast to provocative pharmacological testing in Brugada syndrome, there is limited data on the role of exercise stress testing as a risk stratification modality. The objective of this study was to evaluate the utility of exercise testing in asymptomatic patients with type 1 Brugada pattern to prognosticate major arrhythmic events(MAE) during follow-up...
March 18, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28315570/tp-e-interval-and-tp-e-qtc-ratio-as-novel-surrogate-markers-for-prediction-of-ventricular-arrhythmic-events-in-hypertrophic-cardiomyopathy
#20
Mehmet Kadri Akboğa, Kevser Gülcihan Balcı, Samet Yılmaz, Selahattin Aydın, Çağrı Yayla, Ahmet Göktuğ Ertem, Sefa Ünal, Mustafa Mücahit Balcı, Yücel Balbay, Dursun Aras, Serkan Topaloğlu
OBJECTIVE: Hypertrophic cardiomyopathy (HCM) as a common genetic heart disease characterized by ventricular hypertrophy and myocardial fibrosis is significantly associated with a higher risk of fatal ventricular arrhythmic events (VAEs). We aimed to assess the interval between the peak and the end of the electrocardiographic T wave (Tp-e) and Tp-e/corrected QT (QTc) ratio as candidate markers of ventricular arrhythmias in patients with HCM. METHODS: In this single-center, prospective study, a total of 66 patients with HCM and 88 controls were enrolled...
March 9, 2017: Anatolian Journal of Cardiology
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