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Journal articles on the topic 'Perforation impedance'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Thornton, CurtisLee, and JungHun Choi. "Design of an Impedance-Controlled Hot Snare Polypectomy Device." Sensors 20, no. 1 (2019): 142. http://dx.doi.org/10.3390/s20010142.

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This paper goes through the process of first designing a feedback system that allows for the measuring of impedance while using the hot snare polypectomy method. The electrosurgical unit used in this study was the Olympus PSD-30. After the impedance-controlled feedback system was completed, the device was tested under a range of power settings from 10 W–50 W. The test was performed ex vivo using porcine colon samples. Using the information gathered from these tests, a technique of determining the threshold of perforation and implementing a system to automatically stop the applied current from

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Qian, Yu Jie, Ke Cui, Shu Mei Liu, Zi Bo Li, De Yi Kong, and Shao Ming Sun. "Development of Broadband Ultra Micro-Perforated Panels Based on MEMS Technology." Applied Mechanics and Materials 535 (February 2014): 788–95. http://dx.doi.org/10.4028/www.scientific.net/amm.535.788.

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Fabrication process of ultra micro-perforated panels (ultra-MPPs) with perforations of diameter below 100 um based on MEMS technology is expatiated in this paper. As a promising alternative to the conventional porous absorbing materials, MPP absorber is now being widely used in noise control engineering. Theory reveals that the maximum sound absorption bandwidth of a single MPP absorber could be achieved by reducing the perforation diameter to a certain limit and the desirable perforation diameters are less than 100um under many circumstances. However, due to the limitation of traditional manu

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Atiénzar-Navarro, Roberto, Romina del Rey, Jesús Alba, Víctor J. Sánchez-Morcillo, and Rubén Picó. "Sound Absorption Properties of Perforated Recycled Polyurethane Foams Reinforced with Woven Fabric." Polymers 12, no. 2 (2020): 401. http://dx.doi.org/10.3390/polym12020401.

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The acoustic properties of recycled polyurethane foams are well known. Such foams are used as a part of acoustic solutions in different fields such as building or transport. This paper aims to seek improvements in the sound absorption of these recycled foams when they are combined with fabrics. For this aim, foams have been drilled with cylindrical perforations, and also combined with different fabrics. The effect on the sound absorption is evaluated based on the following key parameters: perforation rate (5% and 20%), aperture size (4 mm and 6 mm), and a complete perforation depth. Experiment

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Yuvaraj, L., and S. Jeyanthi. "Acoustic performance of countersunk micro-perforated panel in multilayer porous material." Building Acoustics 27, no. 1 (2019): 3–20. http://dx.doi.org/10.1177/1351010x19886588.

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This study investigates the acoustic performance of a countersunk micro-perforated panel, along with two distinct porous materials used in a multilayer porous absorber configuration. Additive manufacturing is applied to create sub-millimeter perforation with different hole spacings on polymer micro-perforated panels. Experiments are conducted in an impedance tube, in which the effects of the perforation ratio, air gap, and varying porous layer configurations on the sound absorption capabilities are investigated. For validation, considering the converging hole profile in the micro-perforated pa

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ZHU, F., S. HEDLUND, and D. THIERRY. "Application of electrochemical impedance spectroscopy to study perforation corrosion of automotive materials." British Corrosion Journal 31, no. 2 (1996): 113–18. http://dx.doi.org/10.1179/bcj.1996.31.2.113.

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R., Zulkifli, T. K. Thye, Mohd Faizal Bin Mat Tahir, Ahmad Rasdan Ismail, and Mohd Jailani Mohd Nor. "Automotive Noise Insulation Composite Panel Using Natural Fibres with Different Perforation Areas." Applied Mechanics and Materials 165 (April 2012): 63–67. http://dx.doi.org/10.4028/www.scientific.net/amm.165.63.

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This research was carried out to study the acoustic properties of natural organic fibres; kenaf and coir fibres using impedance tube method. Kenaf fibre was used as noise absorber filler in an insulation panel while the coir fibre as reinforcement in the perforated composite panel. The perforated panel was made from coir fibre/polyester composites with coir fibre volume fraction of 10%, 20% and 30%. The perforation area of the perforated panel was also varied at 10%, 20% and 30%. During the processing stage, the kenaf fibre sheet has been treated with PVA and cut into 100 mm and 30 mm diameter

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Li, Chenxi, Ben Cazzolato, and Anthony Zander. "Acoustic impedance of micro perforated membranes: Velocity continuity condition at the perforation boundary." Journal of the Acoustical Society of America 139, no. 1 (2016): 93–103. http://dx.doi.org/10.1121/1.4939489.

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AKISHITA, Sadao. "2713 Grazing Flow Effect on Surface Impedance with Very Small Bore : Rectangular Perforation." Proceedings of the JSME annual meeting 2008.7 (2008): 107–8. http://dx.doi.org/10.1299/jsmemecjo.2008.7.0_107.

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Lee, Iljae, Ahmet Selamet, and Norman T. Huff. "Impact of perforation impedance on the transmission loss of reactive and dissipative silencers." Journal of the Acoustical Society of America 120, no. 6 (2006): 3706–13. http://dx.doi.org/10.1121/1.2359703.

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Vašina, Martin, and Ondrej Bilek. "Influence of Surface Shape and Perforation of Plastics on Sound Absorption." Applied Mechanics and Materials 474 (January 2014): 393–98. http://dx.doi.org/10.4028/www.scientific.net/amm.474.393.

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The aim of the paper is to study the effect of the surface shape and perforation of plastics on sound absorption. Samples with different asperity heights, depths and numbers of holes were prepared by means of CNC milling machine. Experimental measurements of frequency dependencies of the sound absorption coefficient were realized by the transfer function method using Kundt ́s impedance tube at normal incidence of acoustic wave on the investigated materials. The study was performed on two types of polyurethanes. Different factors, that have influence on sound absorption, are evaluated in the co

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Putra, A., and A. Y. Ismail. "Normal Incidence of Sound Transmission Loss from Perforated Plates with Micro and Macro Size Holes." Advances in Acoustics and Vibration 2014 (April 17, 2014): 1–12. http://dx.doi.org/10.1155/2014/534569.

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This paper studies the sound transmission loss of perforated panels and investigates the effect of the hole diameter on the sound insulation performance under normal incidence of acoustic loading. The hole diameters are distinguished into micro (submillimeter) and macro (millimeter) sizes. In general, the transmission loss reduces as the perforation ratio is increased. However, by retaining the perforation ratio, it is found that the transmission loss increases as the hole diameter is reduced for a perforate with micro holes due to the effect of resistive part in the hole impedance, which is c

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Nakai, Takayoshi. "Simulation of Normal Incidence Sound Absorption Coefficients of Perforated Panels With/Without Glass Wool by Transmission Line Parameters in a Two-Port Network." Rajshahi University Journal of Science and Engineering 44 (November 19, 2016): 123–30. http://dx.doi.org/10.3329/rujse.v44i0.30397.

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This paper describes simulation of normal incidence sound absorption coefficients of perforated panels by transmission line parameters in a two-port network. Maa and Sakagami have investigated micro perforated panels, MPP. But their theories can treat only near 1 % perforation rates of perforated panels with back cavities. If sound propagates as a plane wave, sound propagation can be represented as transmission line parameters in a two-port network. Perforated panels, back cavities, and glass wool absorption materials are represented as matrix of transmission line parameters, respectively. Tra

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Rouane, Amar, and Paul Bru. "High frequency metrology for intracardiac ablation: in-vivo results." Metrology and Measurement Systems 19, no. 3 (2012): 603–10. http://dx.doi.org/10.2478/v10178-012-0053-4.

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Abstract Cardiac Radiofrequency (RF) ablation is a commonly used clinical procedure for treating many cardiac arrhythmias. However, the efficacy of RF ablation may be limited by two factors: small ventricular lesions and impedance rise, leading to coagulum formation and desiccation of tissue. In this paper, a high frequency (HF) energy ablation system operating at 27.12 MHz based on an automated load matching system was developed. A HF energy matched probe associated to the automated impedance matching device ensures optimal transfer of the energy to the load. The aim of this study was to eval

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Yu, Xiao, Li Chen, Qin Fang, Xiaofeng Hou, and Yi Fan. "Blast mitigation effect of the layered concrete structure with an air gap: A numerical approach." International Journal of Protective Structures 9, no. 4 (2018): 432–60. http://dx.doi.org/10.1177/2041419618766951.

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A novel layered concrete structure with an air gap was proposed to resist explosion attacks from terrorist bombings or conventional weapons. The proposed layered structure potentially benefits mitigating the blast wave induced from detonation in the predamaged concrete shelter layer by projectile penetration, because the wave impedance between air and concrete material is far different. To quantitatively evaluate the blast mitigation effects and reveal the blast-resistant mechanism, a fine numerical model of the proposed layered structure was built in LS-DYNA, in which trinitrotoluene explosiv

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Belvin, Diane, David Hirschl, Vineet R. Jain, et al. "Chest Radiographs Are Valuable in Demonstrating Clinically Significant Pacemaker Complications that Require Reoperation." Canadian Association of Radiologists Journal 62, no. 4 (2011): 288–95. http://dx.doi.org/10.1016/j.carj.2010.04.016.

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Purpose To evaluate the utility of chest radiography in demonstrating clinically significant pacemaker complications that required reoperation. Methods In this retrospective case-controlled series, we identified 14 consecutive adults who required pacemaker reoperation and who had chest radiographs available for review (6 men, 8 women; mean age, 71 years [range, 43–95 years]). Ten patients had pacemakers implanted at our institution, and 4 were referred for reoperation. Forty-two controls, 3 for each patient, had postoperative chest radiographs and normal device function (25 men, 17 women; mean

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Bolger, Ciaran, C. Carozzo, T. Roger, et al. "A preliminary study of reliability of impedance measurement to detect iatrogenic initial pedicle perforation (in the porcine model)." European Spine Journal 15, no. 3 (2005): 316–20. http://dx.doi.org/10.1007/s00586-005-1024-1.

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Bolger, Ciaran, C. Carozzo, T. Roger, et al. "A preliminary study of reliability of impedance measurement to detect iatrogenic initial pedicle perforation (in the porcine model)." European Spine Journal 15, no. 10 (2006): 1555. http://dx.doi.org/10.1007/s00586-006-0150-8.

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18

Kim, Myunghoi. "A Dual-Perforation Electromagnetic Bandgap Structure for Parallel-Plate Noise Suppression in Thin and Low-Cost Printed Circuit Boards." Electronics 8, no. 6 (2019): 719. http://dx.doi.org/10.3390/electronics8060719.

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In this study, we propose and analyze a dual-perforation (DP) technique to improve an electromagnetic bandgap (EBG) structure in thin and low-cost printed circuit boards (PCBs). The proposed DP–EBG structure includes a power plane with a square aperture and a patch with an L-shape slot that overcomes efficiently the problems resulting from the low-inductance and the characteristic impedance of the EBG structure developed for parallel-plate noise suppression in thin PCBs. The effects of the proposed dual-perforation technique on the stopband characteristics and unit cell size are analyzed using

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19

Rutledge, James T., and W. Scott Phillips. "Hydraulic stimulation of natural fractures as revealed by induced microearthquakes, Carthage Cotton Valley gas field, east Texas." GEOPHYSICS 68, no. 2 (2003): 441–52. http://dx.doi.org/10.1190/1.1567214.

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We produced a high‐resolution microseismic image of a hydraulic fracture stimulation in the Carthage Cotton Valley gas field of east Texas. We improved the precision of microseismic event locations four‐fold over initial locations by manually repicking the traveltimes in a spatial sequence, allowing us to visually correlate waveforms of adjacent sources. The new locations show vertical containment within individual, targeted sands, suggesting little or no hydraulic communication between the discrete perforation intervals simultaneously treated within an 80‐m section. Treatment (i.e., fracture‐

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20

Merchant, Saumil N., Michael E. Ravicz, Susan E. Voss, William T. Peake, and John J. Rosowski. "Middle ear mechanics in normal, diseased and reconstructed ears." Journal of Laryngology & Otology 112, no. 8 (1998): 715–31. http://dx.doi.org/10.1017/s0022215100141568.

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AbstractA review of the structure-function relationships in normal, diseased and reconstructed middle ears is presented. Variables used to describe the system are sound pressure, volume velocity and acoustic impedance. We discuss the following(1) Sound can be transmitted from the ear canal to the cochlea via two mechanisms: the tympanoossicular system (ossicular coupling) and direct acoustic stimulation of the oval and round windows (acoustic coupling). In the normal ear, middle-ear pressure gain, which is the result of ossicular coupling, is frequency-dependent and smaller than generally beli

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21

Testoni, Pier Alberto, Sabrina Testoni, Giorgia Mazzoleni, et al. "Transoral incisionless fundoplication with an ultrasonic surgical endostapler for the treatment of gastroesophageal reflux disease: 12-month outcomes." Endoscopy 52, no. 06 (2020): 469–73. http://dx.doi.org/10.1055/a-1124-3187.

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Background Transoral incisionless fundoplication (TIF) with the Medigus ultrasonic surgical endostapler (MUSE) is a new intervention for the treatment of the gastroesophageal reflux disease (GERD). The aim of this study was to assess the 12-month clinical, functional, and endoscopic effects of TIF by MUSE. Methods Patients undergoing MUSE completed the GERD-Health Related Quality of Life (GERD-HRQL) and Reflux Symptom Index (RSI) questionnaires, and underwent endoscopy, esophageal 24-hour pH-impedance recording, and high resolution manometry (HRM) before the TIF procedure and 12 months later,

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22

Malick, Nabeel, Raveendra P. Gadag, Vidyashree K. M., and Shruthi Puthukulangara. "Comparative study of type 1 tympanoplasty with and without gelfoam in the middle ear." International Journal of Otorhinolaryngology and Head and Neck Surgery 3, no. 4 (2017): 1036. http://dx.doi.org/10.18203/issn.2454-5929.ijohns20174328.

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<p class="abstract"><strong>Background:</strong> Chronic suppurative otitis media is a widespread disease with a significant cause of morbidity with a greater burden in the poor communities of the developing countries for which tympanoplasty is frequently undertaken. Gelfoam may show detrimental effects such as adhesions and fibrosis and improper packing may physically alter the structure of the tympanic membrane leading to failure of tympanoplasty. The graft can be placed without any middle ear supporting agent wherein the graft is held in position by the surface tension bet

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Bosseboeuf, Adrien, Amandine Baron, Elise Duval, Aude Gautier, Pascal Sourdaine, and Pierrick Auvray. "K092A and K092B, Two Peptides Isolated from the Dogfish (Scyliorhinus canicula L.), with Potential Antineoplastic Activity Against Human Prostate and Breast Cancer Cells." Marine Drugs 17, no. 12 (2019): 672. http://dx.doi.org/10.3390/md17120672.

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Cancer therapy is currently a major challenge within the research community, especially in reducing the side effects of treatments and to develop new specific strategies against cancers that still have a poor prognosis. In this context, alternative strategies using biotechnologies, such as marine peptides, have been developed based on their promise of effectivity associated with a low toxicity for healthy cells. The purpose of the present paper is to investigate the active mechanism of two peptides that were isolated from the epigonal tissue of the lesser spotted dogfish Scyliorhinus canicula

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Selamat, N. S. S., Mohd Faizal Mat Tahir, Rozli Zulkifli, et al. "Development of Semi-Active Panel Design for Sound Absorption." Applied Mechanics and Materials 663 (October 2014): 421–25. http://dx.doi.org/10.4028/www.scientific.net/amm.663.421.

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Various noise-absorbing materials and apparatus were developed not only for industry purposes but also for increased personal convenience through the absorption of unwanted sound. Absorbing products are typically passive mediums, whereas active-control absorption is expensive and complicated to install. Thus, in this study, a semi-active panel design for the sound absorber is developed to ensure operation at a required absorption level for a particular environment and to allow manual control. This study focused on producing an optimum design from several blueprints by using the simulation prog

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Surowska, Barbara, Monika Ostapiuk, Patryk Jakubczak, and Magda Droździel. "The Durability of an Organic–Inorganic Sol–Gel Interlayer in Al-GFRP-CFRP Laminates in a Saline Environment." Materials 12, no. 15 (2019): 2362. http://dx.doi.org/10.3390/ma12152362.

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The aim of the study was to assess the selected properties of a hybrid organic–inorganic silane sol–gel coating (HSG) used in hybrid fiber metal laminates (FML) in a corrosion environment. The HSG coating on the aluminum alloy was produced using 3M™ AC130-2 formulation consisting of 3-glycidoxypropyl-trimethoxysilane (GPTMS) and tetra-n-propoxyzirconium (zirconium(IV) propoxide) (TPOZ). Laminates consisted of aluminum alloy AA2024-T3 sheets, with carbon fiber reinforced polymers (CFRPs) and a glass fiber reinforced metal–composite structure (GFRP). Potentiodynamic and polarization curve and im

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Kusaka, Midori, Kimihiro Sakagami, and Takeshi Okuzono. "A Basic Study on the Absorption Properties and Their Prediction of Heterogeneous Micro-Perforated Panels: A Case Study of Micro-Perforated Panels with Heterogeneous Hole Size and Perforation Ratio." Acoustics 3, no. 3 (2021): 473–85. http://dx.doi.org/10.3390/acoustics3030031.

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Micro-perforated panels (MPPs) are one of the most promising alternatives to conventional porous sound-absorbing materials. Traditionally, the theory of the sound absorption properties of MPPs is based on the assumption that MPPs are a homogeneous material with identical pores at regular intervals. However, in recent years, some MPPs have not met these conditions, and although a variety of designs have been created, their properties and prediction methods were studied in only fewer works. In this paper, considering the wide variety of MPP designs, we made a trial production of heterogeneous MP

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Lee, Iljae, Ahmet Selamet, and Norman T. Huff. "Acoustic impedance of perforations in contact with fibrous material." Journal of the Acoustical Society of America 119, no. 5 (2006): 2785–97. http://dx.doi.org/10.1121/1.2188354.

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Lee, Iljae, Ahmet Selamet, and Norman Huff. "Acoustic impedance of perforations in contact with absorbing material." Journal of the Acoustical Society of America 119, no. 5 (2006): 3412. http://dx.doi.org/10.1121/1.4786799.

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DHIA, A. S. BONNET-BEN, D. DRISSI, and N. GMATI. "MATHEMATICAL ANALYSIS OF THE ACOUSTIC DIFFRACTION BY A MUFFLER CONTAINING PERFORATED DUCTS." Mathematical Models and Methods in Applied Sciences 15, no. 07 (2005): 1059–90. http://dx.doi.org/10.1142/s0218202505000649.

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We consider the three-dimensional scalar problem of acoustic propagation in a muffler. We develop and analyze a Fredholm-type formulation for a stationary fluid in the time-harmonic setting. We prove a homogenization result for a muffler containing periodically perforated ducts. Essentially, the perforated boundaries become completely transparent when the period of perforations, which is assumed to be of the same order as the size of perforations, tends to zero. We also derive a homogenized impedance condition when the perforated duct is coated by an absorbing material. We present numerical ex

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Tanttari, Jukka, Erin Komi, Antti Hynninen, et al. "Additive Manufacturing of Silencers with Microperforates." Advances in Acoustics and Vibration 2018 (October 14, 2018): 1–13. http://dx.doi.org/10.1155/2018/7649756.

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A microperforated panel (MPP) is generally defined as a perforated plate, in which the impedance of below one millimetre perforations is dominated by viscous losses. Using MPPs in duct and silencer applications, target is to maximize transmission loss (TL) by choosing proper surface impedance parameters. Additive manufacturing (AM) has recently reduced conventional design limitations and enabled fast prototyping of complex shaped structures. MPP-based model scale silencers can be printed within reasonable time, price, and accuracy. In this paper, design and validation of AM silencers with MPPs

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Behan, Felix. "A keystone solution for major head and neck reconstructions." Australasian Journal of Plastic Surgery 2, no. 2 (2019): 79–83. http://dx.doi.org/10.34239/ajops.v2n2.154.

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This ‘How to do it’ lists a range of cases, demonstrated by supplementary video discussion, that explain the refinements of the keystone perforator island flap (KPIF) technique applied to specific sites of the head and neck, with a focus on the elderly. When the P A C E acronym is applied (pain-free, aesthetic outcome, minimal complications, economical) the KPIF technique is a respectable alternative to microvascular surgery, particularly in the elderly, with minimal returns to theatre for vascular impedance problems which are not infrequent in microvascular reconstructions.

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Castagnola, Elisa, Marco Marrani, Emma Maggiolini, et al. "Recording High Frequency Neural Signals Using Conformable and Low-Impedance ECoG Electrodes Arrays Coated with PEDOT-PSS-PEG." Advances in Science and Technology 102 (October 2016): 77–85. http://dx.doi.org/10.4028/www.scientific.net/ast.102.77.

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Electrocorticography (ECoG) is receiving growing attention for both clinical and research applications thanks to its reduced invasiveness and ability of addressing large cortical areas. These benefits come with a main drawback, i.e. a limited frequency bandwidth. However, recent studies have shown that spiking activity from cortical neurons can be recorded when the ECoG grids present the following combined properties: (I) conformable substrate, (II) small neuron-sized electrodes with (III) low-impedance interfaces. We introduce here an ad-hoc designed ECoG device for investigating how electrod

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Maury, Cédric, and Teresa Bravo. "Enhanced modal matching method for perforated and micro-perforated partitions." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 6 (2021): 287–97. http://dx.doi.org/10.3397/in-2021-1404.

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Perforated multilayer partitions are widely used in many problems for the aerospace and automotive industries and air-conditioning systems. Combinations of macro and micro-perforated perforations across the constitutive partition layers can provide different physical mechanisms for diverse control strategies depending on the problem requirements. However, there is a lack of unified numerical or analytical description able to provide accurate results over a broad frequency range for a wide range of diameter perforations ranging from supra-millimetric to sub-millimetric apertures. Furthermore, m

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Carrillo, Ryner Jose D., Precious Eunice R. Grullo, and Maria Luz M. San Agustin. "A Cotton Wick Improves Hearing in a Patient with Profound Hearing Loss." Philippine Journal of Otolaryngology-Head and Neck Surgery 30, no. 2 (2015): 56–58. http://dx.doi.org/10.32412/pjohns.v30i2.357.

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Dear Editor,  The tympanic membrane and the ossicular chain contribute roughly 28 dB in hearing gain. In chronic suppurative otitis media, loss of tympanic membrane and lysis of the ossicular chain are significant causes of hearing loss.1 Through the years, hearing impairment has been augmented using various devices such as ear trumpets, carbon hearing aids, vacuum tube and transistor hearing aids, bone anchored hearing aids, and cochlear implants.2 This case report describes how a cotton wick was used to amplify sound.  Case Report A 65-year-old man consulted for

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Lee, Iljae, and Ahmet Selamet. "Measurement of acoustic impedance of perforations in contact with absorbing material in the presence of mean flow." Noise Control Engineering Journal 60, no. 3 (2012): 258–66. http://dx.doi.org/10.3397/1.3701003.

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Sakagami, Kimihiro, Midori Kusaka, Takeshi Okuzono, and Shinsuke Nakanishi. "The Effect of Deviation Due to the Manufacturing Accuracy in the Parameters of an MPP on Its Acoustic Properties: Trial Production of MPPs of Different Hole Shapes Using 3D Printing." Acoustics 2, no. 3 (2020): 605–16. http://dx.doi.org/10.3390/acoustics2030032.

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In this study, we discuss the effect of the manufacturing accuracy of a microperforated panel (MPP) produced by 3D printers on acoustic properties through measured and calculated results as a pilot study. The manufacturing costs of MPPs have long been one of their shortcomings; however, with recent developments in the manufacturing process, low-cost MPPs are now available. In a further attempt at reducing the cost, 3D printing techniques have recently been considered. Cases of trial production of MPPs manufactured by 3D printing have been reported. When introducing such new techniques, despite

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Lombardo, S., JJ Orr, DA Coley, and MJ Wood. "A new route to exposed thermal mass: Sound-absorbing poured concrete." Building Services Engineering Research and Technology 38, no. 4 (2017): 408–20. http://dx.doi.org/10.1177/0143624417698833.

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This paper investigates the novel possibility of utilising the structural concrete floor slab as a means of providing additional mid- to low-frequency sound absorption through the addition of cavities on the ceiling side, formed using flexible formwork, acting as Helmholtz resonators. Mid- to low-frequency sound absorption in rooms is typically achieved through the use of perforated plasterboard or a suspended tile-in-grid system. Such an approach can separate the room from the thermal mass of the ceiling above, leading to higher peak temperatures or increased cooling load. Suspended ceilings

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PESTREA, Catalin, Alexandra GHERGHINA, Irina PINTILIE, and Florin ORTAN. "Learning Curve for Left Bundle Branch Area Pacing – the Experience of a Romanian Academic Center." Romanian Journal of Cardiology 31, no. 2 (2021): 327–34. http://dx.doi.org/10.47803/rjc.2021.31.2.327.

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Introduction: There is an increasing interest in the past decade for more physiological pacing strategies due to detrimental long-term right ventricular pacing. His bundle pacing is the most physiological one, but it has some drawbacks, mainly an increased pacing threshold. Left bundle branch area pacing (LBBAP) emerged in the recent years as the next step in conduction system pacing. We present our initial experience and learning curve with this latter procedure. Material and methods: During January 2019 and February 2021, 20 patients with pacing indications that failed initial permanent His

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Zhang, Zhizhong, Tianyang Zheng, and Rong Zhu. "Single-cell individualized electroporation with real-time impedance monitoring using a microelectrode array chip." Microsystems & Nanoengineering 6, no. 1 (2020). http://dx.doi.org/10.1038/s41378-020-00196-0.

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Abstract The ability to precisely deliver molecules into single cells while maintaining good cell viability is of great importance to applications in therapeutics, diagnostics, and drug delivery as it is an advancement toward the promise of personalized medicine. This paper reports a single-cell individualized electroporation method with real-time impedance monitoring to improve cell perforation efficiency and cell viability using a microelectrode array chip. The microchip contains a plurality of sextupole-electrode units patterned in an array, which are used to perform in situ electroporation

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Allam, S., and M. Åbom. "A New Type of Muffler Based on Microperforated Tubes." Journal of Vibration and Acoustics 133, no. 3 (2011). http://dx.doi.org/10.1115/1.4002956.

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Microperforated plate (MPP) absorbers are perforated plates with holes typically in the submillimeter range and perforation ratios around 1%. The values are typical for applications in air at standard temperature and pressure (STP). The underlying acoustic principle is simple: It is to create a surface with a built in damping, which effectively absorbs sound waves. To achieve this, the specific acoustic impedance of a MPP absorber is normally tuned to be of the order of the characteristic wave impedance in the medium (∼400 Pa s/m in air at STP). The traditional application for MPP absorbers ha

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Li, X. F., H. Li, X. H. Fan, et al. "P6017Permanent left bundle branch area pacing for atrioventricular block: feasibility, safety and acute effect." European Heart Journal 40, Supplement_1 (2019). http://dx.doi.org/10.1093/eurheartj/ehz746.0737.

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Abstract Background Left bundle branch area pacing (LBBAP), lacks adequate evaluation for AVB. Purpose We aimed to assess the feasibility, safety, and acute clinical outcomes of permanent LBBAP in patients with AVB. Methods We retrospectively recruited AVB patients with indication for ventricular pacing who had underwent LBBAP from May to Sep. 2018. ECG characteristics, pacing parameters, echocardiographic parameters and adverse events were evaluated during follow-up. Successful LBBAP was defined as the paced QRS morphology of RBBB pattern and QRSd less than 130ms. Results A total of 33 patien

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Anwander, M., T. Kueffer, M. Branca, et al. "P2855Unexpectedly high rate of lead failure of the Microport (formerly Sorin/Livanova) Beflex and Vega pacemaker electrodes: A single centre experience." European Heart Journal 40, Supplement_1 (2019). http://dx.doi.org/10.1093/eurheartj/ehz748.1164.

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Abstract Introduction Pacing leads remain the weak link of current pacemaker systems. Various differences in design and material exist among companies. Lead performance is mainly assessed via post-marketing studies of the manufacturing companies. Reliable independent reports are rare. We aimed to study the early and long-term performance of the Microport (formerly Sorin/Livanova) Beflex and Vega leads at our centre, for which a lead survival >99% at 3 years has been reported by the company. Method In this single centre, retrospective study we analysed the performance of all right ventricula

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Cui, Yan-Yu, Yong-Xiang Qin, Qing-Miao Ding, and Yu-Ning Gao. "Study on corrosion behavior of X80 steel under stripping coating by sulfate reducing bacteria." BMC Biotechnology 21, no. 1 (2021). http://dx.doi.org/10.1186/s12896-020-00664-5.

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Abstract Background At present, microorganism has been considered as important factors that threaten to buried pipelines with disbonded coatings. Aiming at the problem of unknown corrosion mechanism of sulfate-reducing bacteria (SRB), a series of studies have been carried out in this paper. Spectrophotometer and fluorescent labeling technology are used to study the growth and attachment of SRB in the simulated soil solution. The corrosion behavior of X80 pipeline steel with or without SRB was researched by electrochemical methods such as open circuit potential, dynamic potential polarization c

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Cui, Yan-Yu, Yong-Xiang Qin, Qing-Miao Ding, and Yu-Ning Gao. "Study on corrosion behavior of X80 steel under stripping coating by sulfate reducing bacteria." BMC Biotechnology 21, no. 1 (2021). http://dx.doi.org/10.1186/s12896-020-00664-5.

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Abstract Background At present, microorganism has been considered as important factors that threaten to buried pipelines with disbonded coatings. Aiming at the problem of unknown corrosion mechanism of sulfate-reducing bacteria (SRB), a series of studies have been carried out in this paper. Spectrophotometer and fluorescent labeling technology are used to study the growth and attachment of SRB in the simulated soil solution. The corrosion behavior of X80 pipeline steel with or without SRB was researched by electrochemical methods such as open circuit potential, dynamic potential polarization c

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Van Den Broek, JLPM, FALE Bracke, I. Stranders, MNJ Op "T Hof, and LM Rademakers. "Initial experience, feasibility and safety of permanent left bundle branch pacing; a retrospective single centre study." EP Europace 23, Supplement_3 (2021). http://dx.doi.org/10.1093/europace/euab116.436.

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Abstract Funding Acknowledgements Type of funding sources: None. Background Physiologic pacing by left bundle branch pacing (LBBP) is characterized by direct stimulation of the intrinsic His-Purkinje system and results in physiologic ventricular depolarization and repolarization. This technique has emerged as an alternative to both traditional right ventricular pacing for bradycardia and classic cardiac resynchronization therapy (CRT). High success rates and low complication rates are reported, however the majority of literature is reported by relatively few, highly experienced centres. Purpos

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Kim, Daesik, Seungchai Jung, and Heeho Park. "Design of Acoustic Liner in Small Gas Turbine Combustor Using One-Dimensional Impedance Models." Journal of Engineering for Gas Turbines and Power 140, no. 12 (2018). http://dx.doi.org/10.1115/1.4040765.

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The side-wall cooling liner in a gas turbine combustor serves main purposes—heat transfer and emission control. Additionally, it functions as a passive damper to attenuate thermoacoustic instabilities. The perforations in the liner mainly convert acoustic energy into kinetic energy through vortex shedding at the orifice rims. In the previous decades, several analytical and semi-empirical models have been proposed to predict the acoustic damping of the perforated liner. In the current study, a few of the models are considered to embody the transfer matrix method (TMM) for analyzing the acoustic

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So, T. "Success and failure for implantation of left bundle branch pacing using stylet-driven pacing leads : a single center experience." EP Europace 23, Supplement_3 (2021). http://dx.doi.org/10.1093/europace/euab116.398.

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Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction :Left bundle area pacing is a new modality of physiological pacing. By screwing the pacing lead deep into the interventricular septum, the left bundle branch could be recruited for pacing purpose. Initially left bundle area pacing was performed with fixed helix lead supported by the delivery catheter. On the other hand, there are studies showing the feasibility of using a style-driven extendable helix with the new delivery sheath for left bundle area pacing. Purpose :To study the feasibility of left bundle

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