keyword
MENU ▼
Read by QxMD icon Read
search

Voltage Mapping

keyword
https://www.readbyqxmd.com/read/28928669/nature-s-electric-potential-a-systematic-review-of-the-role-of-bioelectricity-in-wound-healing-and-regenerative-processes-in-animals-humans-and-plants
#1
REVIEW
Sheena E B Tyler
Natural endogenous voltage gradients not only predict and correlate with growth and development but also drive wound healing and regeneration processes. This review summarizes the existing literature for the nature, sources, and transmission of information-bearing bioelectric signals involved in controlling wound healing and regeneration in animals, humans, and plants. It emerges that some bioelectric characteristics occur ubiquitously in a range of animal and plant species. However, the limits of similarities are probed to give a realistic assessment of future areas to be explored...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28892102/length-independent-dna-packing-into-nanopore-zero-mode-waveguides-for-low-input-dna-sequencing
#2
Joseph Larkin, Robert Y Henley, Vivek Jadhav, Jonas Korlach, Meni Wanunu
Compared with conventional methods, single-molecule real-time (SMRT) DNA sequencing exhibits longer read lengths than conventional methods, less GC bias, and the ability to read DNA base modifications. However, reading DNA sequence from sub-nanogram quantities is impractical owing to inefficient delivery of DNA molecules into the confines of zero-mode waveguides-zeptolitre optical cavities in which DNA sequencing proceeds. Here, we show that the efficiency of voltage-induced DNA loading into waveguides equipped with nanopores at their floors is five orders of magnitude greater than existing methods...
September 11, 2017: Nature Nanotechnology
https://www.readbyqxmd.com/read/28887365/omnipolar-mapping-a-method-to-improve-the-fidelity-of-voltage-mapping-to-guide-substrate-based-atrial-fibrillation-ablation
#3
EDITORIAL
Jackson J Liang, Cory M Tschabrunn, Francis E Marchlinski
No abstract text is available yet for this article.
September 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28887362/resolving-bipolar-electrogram-voltages-during-atrial-fibrillation-using-omnipolar-mapping
#4
Shouvik K Haldar, Karl Magtibay, Andreu Porta-Sanchez, Stéphane Massé, Nicholas Mitsakakis, Patrick F H Lai, Mohammed Ali Azam, John Asta, Marjan Kusha, Paul Dorian, Andrew C T Ha, Vijay Chauhan, D Curtis Deno, Kumaraswamy Nanthakumar
BACKGROUND: Low-voltage-guided substrate modification is an emerging strategy in atrial fibrillation (AF) ablation. A major limitation to contemporary bipolar electrogram (EGM) analysis in AF is the resultant lower peak-to-peak voltage (Vpp) from variations in wavefront direction relative to electrode orientation and from fractionation and collision events. We aim to compare bipole Vpp with novel omnipolar peak-to-peak voltages (Vmax) in sinus rhythm (SR) and AF. METHODS AND RESULTS: A high-density fixed multielectrode plaque was placed on the epicardial surface of the left atrium in dogs...
September 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28886660/a-multi-plate-velocity-map-imaging-design-for-high-resolution-photoelectron-spectroscopy
#5
Steven J Kregel, Glen K Thurston, Jia Zhou, Etienne Garand
A velocity map imaging (VMI) setup consisting of multiple electrodes with three adjustable voltage parameters, designed for slow electron velocity map imaging applications, is presented. The motivations for this design are discussed in terms of parameters that influence the VMI resolution and functionality. Particularly, this VMI has two tunable potentials used to adjust for optimal focus, yielding good VMI focus across a relatively large energy range. It also allows for larger interaction volumes without significant sacrifice to the resolution via a smaller electric gradient at the interaction region...
September 7, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28884923/low-voltage-areas-detected-by-high-density-electroanatomical-mapping-predict-recurrence-after-ablation-for-paroxysmal-atrial-fibrillation
#6
Konstantinos Vlachos, Michael Efremidis, Konstantinos P Letsas, George Bazoukis, Ruairidh Martin, Maria Kalafateli, Louiza Lioni, Stamatis Georgopoulos, Athanasios Saplaouras, Theodore Efremidis, Tong Liu, Kosmas Valkanas, Nikolaos Karamichalakis, Dimitrios Asvestas, Antonios Sideris
INTRODUCTION: We aimed to evaluate the extent of atrial fibrosis in paroxysmal atrial fibrillation (AF) and the correlation with ablation outcomes after pulmonary vein antral isolation (PVΑI) using a mapping system with high-resolution and high-spatial sampling. METHODS AND RESULTS: We prospectively enrolled 80 consecutive patients (45 males, median age 60.26 years) with symptomatic paroxysmal AF who were scheduled for PVAI. Prior to PVAI, high-density bipolar voltage mapping (median number of 2,485 points) was carried out during sinus rhythm in all patients...
September 8, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28878213/contactless-graphene-conductivity-mapping-on-a-wide-range-of-substrates-with-terahertz-time-domain-reflection-spectroscopy
#7
Hungyen Lin, Philipp Braeuninger-Weimer, Varun S Kamboj, David S Jessop, Riccardo Degl'Innocenti, Harvey E Beere, David A Ritchie, J Axel Zeitler, Stephan Hofmann
We demonstrate how terahertz time-domain spectroscopy (THz-TDS) operating in reflection geometry can be used for quantitative conductivity mapping of large area chemical vapour deposited graphene films on sapphire, silicon dioxide/silicon and germanium. We validate the technique against measurements performed with previously established conventional transmission based THz-TDS and are able to resolve conductivity changes in response to induced back-gate voltages. Compared to the transmission geometry, measurement in reflection mode requires careful alignment and complex analysis, but circumvents the need of a terahertz transparent substrate, potentially enabling fast, contactless, in-line characterisation of graphene films on non-insulating substrates such as germanium...
September 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28868212/high-density-mapping-of-brain-slices-using-a-large-multi-functional-high-density-cmos-microelectrode-array-system
#8
Vijay Viswam, Raziyeh Bounik, Amir Shadmani, Jelena Dragas, Marie Obien, Jan Müller, Yihui Chen, Andreas Hierlemann
We present a CMOS-based high-density microelectrode array (HD-MEA) system that enables high-density mapping of brain slices in-vitro with multiple readout modalities. The 4.48×2.43 mm(2) array consists of 59,760 micro-electrodes at 13.5 µm pitch (5487 electrodes/mm(2)). The overall system features 2048 action-potential, 32 local-field-potential and 32 current recording channels, 32 impedance-measurement and 28 neurotransmitter-detection channels and 16 voltage/current stimulation channels. The system enables real-time and label-free monitoring of position, size, morphology and electrical activity of brain slices...
June 2017: Int Solid State Sens Actuators Microsyst Conf
https://www.readbyqxmd.com/read/28865490/mapping-insecticide-resistance-and-characterization-of-resistance-mechanisms-in-anopheles-arabiensis-diptera-culicidae-in-ethiopia
#9
Eba Alemayehu, Abebe Asale, Kasahun Eba, Kefelegn Getahun, Kora Tushune, Astrid Bryon, Evangelia Morou, John Vontas, Thomas Van Leeuwen, Luc Duchateau, Delenasaw Yewhalaw
BACKGROUND: The emergence and spread of insecticide resistance in the major African malaria vectors Anopheles gambiae (s.s.) and An. arabiensis may compromise the current vector control interventions and threatens the global malaria control and elimination efforts. METHODS: Insecticide resistance was monitored in several study sites in Ethiopia from 2013 to 2015 using papers impregnated with discriminating concentrations of DDT, deltamethrin, bendiocarb, propoxur, malathion, fenitrothion and pirimiphos-methyl, following the WHO insecticide susceptibility test procedure...
September 2, 2017: Parasites & Vectors
https://www.readbyqxmd.com/read/28863155/electrophysiological-characteristics-of-pressure-overload-induced-cardiac-hypertrophy-and-its-influence-on-ventricular-arrhythmias
#10
Xiaowei Chen, Mu Qin, Weifeng Jiang, Yu Zhang, Xu Liu
OBJECTIVE: To explore the cardiac electrophysiological characteristics of cardiac hypertrophy and its influence on the occurrence of ventricular tachyarrhythmias. METHODS: Adult C57BL6 mice were randomly divided into a surgery group and a control group. Thoracic aortic constriction was performed on mice in the surgery group, and cardiac anatomical and ultrasonic evaluations were performed to confirm the success of the cardiac hypertrophy model 4 weeks after the operation...
2017: PloS One
https://www.readbyqxmd.com/read/28862942/physiological-assessment-of-ventricular-myocardial-voltage-using-omnipolar-electrograms
#11
Karl Magtibay, Stéphane Massé, John Asta, Marjan Kusha, Patrick F H Lai, Mohammed Ali Azam, Andreu Porta-Sanchez, Shouvik Haldar, Daniel Malebranche, Christopher Labos, D Curtis Deno, Kumaraswamy Nanthakumar
BACKGROUND: Characterization of myocardial health by bipolar electrograms are critical for ventricular tachycardia therapy. Dependence of bipolar electrograms on electrode orientation may reduce reliability of voltage assessment along the plane of arrhythmic myocardial substrate. Hence, we sought to evaluate voltage assessment from orientation-independent omnipolar electrograms. METHODS AND RESULTS: We mapped the ventricular epicardium of 5 isolated hearts from each species-healthy rabbits, healthy pigs, and diseased humans-under paced conditions...
August 16, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/28862787/panoramic-atrial-mapping-with-basket-catheters-a-quantitative-analysis-to-optimize-practice-patient-selection-and-catheter-choice
#12
Shohreh Honarbakhsh, Richard J Schilling, Rui Providência, Gurpreet Dhillon, Vinit Sawhney, Claire A Martin, Emily Keating, Malcolm Finlay, Syed Ahsan, Anthony Chow, Mark J Earley, Ross J Hunter
INTRODUCTION: Panoramic mapping with basket catheters have been used to map atrial fibrillation (AF). However, the limited tissue contact and coverage achieved has raised concerns. METHODS AND RESULTS: Patients undergoing catheter ablation for atrial tachycardia (AT) and persistent AF were recruited. Unipolar signals were recorded with the Constellation or FIRMap catheters. The proportion and distribution of anatomical coverage by the catheters was determined and tissue contact achieved measured...
September 1, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28862430/conformation-manipulation-and-motion-of-a-double-paddle-molecule-on-an-au-111-surface
#13
We-Hyo Soe, Yasuhiro Shirai, Corentin Durand, Yusuke Yonamine, Kosuke Minami, Xavier Bouju, Marek Kolmer, Katsuhiko Ariga, Christian Joachim, Waka Nakanishi
The molecular conformation of a bisbinaphthyldurene (BBD) molecule is manipulated using an LT-UHV STM on an Au(111) surface. BBD has two binaphthyl groups at both ends connected to a central durene leading to anti/syn/flat conformers. In solution, dynamic NMR indicated the fast interexchange between the anti and syn conformers as confirmed by DFT calculations. After deposition in a sub-monolayer on an Au(111) surface, only the syn conformers were observed forming small islands of self-assembled syn dimers. The syn dimers can be separated in 2 syn monomers by STM molecular manipulations...
September 1, 2017: ACS Nano
https://www.readbyqxmd.com/read/28854989/three-dimensional-nanoscale-mapping-of-state-of-the-art-field-effect-transistors-finfets
#14
Pritesh Parikh, Corey Senowitz, Don Lyons, Isabelle Martin, Ty J Prosa, Michael DiBattista, Arun Devaraj, Y Shirley Meng
The semiconductor industry has seen tremendous progress over the last few decades with continuous reduction in transistor size to improve device performance. Miniaturization of devices has led to changes in the dopants and dielectric layers incorporated. As the gradual shift from two-dimensional metal-oxide semiconductor field-effect transistor to three-dimensional (3D) field-effect transistors (finFETs) occurred, it has become imperative to understand compositional variability with nanoscale spatial resolution...
August 31, 2017: Microscopy and Microanalysis
https://www.readbyqxmd.com/read/28842915/roles-of-impaired-intracellular-calcium-cycling-in-arrhythmogenicity-of-diabetic-mouse-model
#15
Chung-Chuan Chou, Chien-Te Ho, Hui-Ling Lee, Yen Chu, Tzung-Hai Yen, Ming-Shien Wen, Shien-Fong Lin, Cheng-Hung Lee, Po-Cheng Chang
BACKGROUND: Diabetes mellitus is associated an increased risk of ventricular arrhythmias (VA), but the underlying electrophysiological mechanisms are not fully explored. This study was aimed to test whether dynamic factors and Cai handling play roles in arrhythmogenesis of a diabetic animal model. METHODS: We used 26 db/db type 2 diabetes mice and 28 control mice in this study. VA inducibility was evaluated in vivo under isoflurane general anesthesia. The intracellular Ca(2+) (Cai ) and membrane voltage (Vm ) signals of the Langendorff-perfused mouse hearts were simultaneously recorded using the optical mapping technique...
August 26, 2017: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/28837051/area-selective-atomic-layer-deposition-of-ru-on-electron-beam-written-pt-c-patterns-versus-sio2-substratum
#16
Marcel Junige, Markus Löffler, Marion Geidel, Matthias Albert, Johann W Bartha, Ehrenfried Zschech, Bernd Rellinghaus, Willem F van Dorp
Area selectivity is an emerging sub-topic in the field of atomic layer deposition (ALD), which employs opposite nucleation phenomena to distinct heterogeneous starting materials on a surface. In this paper, we intend to grow Ru exclusively on locally pre-defined Pt patterns, while keeping a SiO2 substratum free from any deposition. In a first step, we study in detail the Ru ALD nucleation on SiO2 and clarify the impact of the set-point temperature. An initial incubation period with actually no growth was revealed before a formation of minor, isolated RuO x islands; clearly no continuous Ru layer formed on SiO2...
August 24, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28834300/updating-in-vivo-and-in-vitro-phosphorylation-and-methylation-sites-of-voltage-gated-kv7-2-potassium-channels
#17
Fatma Asli Erdem, Isabella Salzer, Seok Heo, Wei-Qiang Chen, Gangsoo Jung, Gert Lubec, Stefan Boehm, Jae-Won Yang
Voltage-gated Kv7.2 potassium channels regulate neuronal excitability. The gating of these channels is tightly controlled by various mediators and neurotransmitters acting via G protein-coupled receptors (GPCRs); the underlying signalling cascades involve phosphatidylinositol-4,5-bisphosphate (PIP2 ), Ca(2+) /Calmodulin and phosphorylation. Recent studies found that the PIP2 sensitivity of Kv7.2 channels is affected by two post-translational modifications, phosphorylation and methylation, harboured within putative PIP2 binding domains...
August 18, 2017: Proteomics
https://www.readbyqxmd.com/read/28829605/microscopic-origin-of-the-valley-hall-effect-in-transition-metal-dichalcogenides-revealed-by-wavelength-dependent-mapping
#18
Nicolas Ubrig, Sanghyun Jo, Marc Philippi, Davide Costanzo, Helmuth Berger, Alexey B Kuzmenko, Alberto F Morpurgo
The band structure of many semiconducting monolayer transition metal dichalcogenides (TMDs) possesses two degenerate valleys with equal and opposite Berry curvature. It has been predicted that, when illuminated with circularly polarized light, interband transitions generate an unbalanced nonequilibrium population of electrons and holes in these valleys, resulting in a finite Hall voltage at zero magnetic field when a current flows through the system. This is the so-called valley Hall effect that has recently been observed experimentally...
September 13, 2017: Nano Letters
https://www.readbyqxmd.com/read/28805218/electrochemical-de-lithiation-of-silver-ferrite-and-composites-mechanistic-insights-from-ex-situ-in-situ-and-operando-x-ray-techniques
#19
Jessica L Durham, Alexander B Brady, Christina A Cama, David C Bock, Christopher J Pelliccione, Qing Zhang, Mingyuan Ge, Yue Ru Li, Yiman Zhang, Hanfei Yan, Xiaojing Huang, Yong Chu, Esther S Takeuchi, Kenneth J Takeuchi, Amy C Marschilok
The structure of pristine AgFeO2 and phase makeup of Ag0.2FeO1.6 (a one-pot composite comprised of nanocrystalline stoichiometric AgFeO2 and amorphous γ-Fe2O3 phases) was investigated using synchrotron X-ray diffraction. A new stacking-fault model was proposed for AgFeO2 powder synthesized using the co-precipitation method. The lithiation/de-lithiation mechanisms of silver ferrite, AgFeO2 and Ag0.2FeO1.6 were investigated using ex situ, in situ, and operando characterization techniques. An amorphous γ-Fe2O3 component in the Ag0...
August 23, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28800169/global-multielectrode-contact-mapping-plus-ablation-with-a-single-catheter-preclinical-and-preliminary-experience-in-humans-with-atrial-fibrillation
#20
Hans Kottkamp, Fabian Moser, Andreas Rieger, Doreen Schreiber, Christian Pönisch, Monica Trofin
INTRODUCTION: One question for the technological advancement of catheter ablation of atrial fibrillation (AF) is whether a creative new concept can combine and even improve the diagnostic mapping options of single-tip and basket catheters with the simplicity of the use of balloon catheters for ablation. Herein, we describe the first in-human experience with a single catheter offering such a complete solution. METHODS AND RESULTS: A new catheter (Globe(®) ) with a distal multielectrode array consisting of 16 ribs with 122 gold-plated electrodes was used...
August 11, 2017: Journal of Cardiovascular Electrophysiology
keyword
keyword
36641
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"