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Waveform duration

Tolga Karacan, Taner Usta, Aysel Ozkaynak, Omer Onur Cakir, Aslı Kahraman, Eser Ozyurek
BACKGROUND/AIMS: The objective of this study was to compare the depth and width of thermal spread caused on rat uterine tissue after application of 3 different electrosurgical generators. METHODS: Alsa Excell 350 MCDSe (Unit A), Meditom DT-400P (Unit M), and ERBE Erbotom VIO 300 D (Unit E) electrosurgical units (ESUs) were used. The number of Wistar Hannover rats required to obtain valid results was 10. The primary objective of the study was to compare the 3 ESUs using the same instrument and the same waveform...
May 23, 2018: Gynecologic and Obstetric Investigation
Ido Barth, Nathaniel J Fisch
In its usual implementation, the Raman amplifier features only one pump carrier frequency. However, pulses with well-separated frequencies can also be Raman amplified while compressed in time. Amplification with frequency-separated pumps is shown to hold even in the highly nonlinear, pump-depletion regime, as derived through a fluid model, and demonstrated via particle-in-cell simulations. The resulting efficiency is similar to single-frequency amplifiers, but, due to the beat-wave waveform of both the pump lasers and the amplified seed pulses, these amplifiers feature higher seed intensities with a shorter spike duration...
March 2018: Physical Review. E
Kenneth S Henry, Kristina S Abrams
Permanent loss of auditory nerve (AN) fibers occurs with increasing age and sound overexposure, sometimes without hair cell damage or associated audiometric threshold elevation. Rodent studies suggest effects of AN damage on central processing and behavior, but these species have limited capacity to discriminate low-frequency speech-like sounds. Here, we introduce a new animal model of AN damage in an avian communication specialist, the budgerigar (Melopsittacus undulatus). The budgerigar is a vocal learner and speech mimic with sensitive low-frequency hearing and human-like behavioral sensitivity to many complex signals including speech components...
May 9, 2018: Journal of the Association for Research in Otolaryngology: JARO
Krystal E Sully, Aatif M Husain
Generalized periodic discharges (GPDs) are generalized discharges that recur with a relatively uniform morphology and duration. They have a quantifiable interdischarge interval. Over the past decade, our understanding of these waveforms has improved considerably. The nomenclature has changed, and etiologic references have been removed. Many disease states can cause GPDs, such as anoxia, toxic/metabolic encephalopathy, infections, nonconvulsive status epilepticus, and hypothermia. Generally, GPDs are morphologically similar regardless of etiology...
May 2018: Journal of Clinical Neurophysiology: Official Publication of the American Electroencephalographic Society
Timothy A Ebert, Elaine A Backus, Michael E Rogers
Electropenetrography a.k.a. electrical penetration graph or EPG is a rigorous technique for studying arthropod behavior. Essentially, the arthropod and host are part of an electrical circuit that generates patterns of voltage (waveforms), whose biological meanings are defined by correlation with histology and behavior. EPG is used for studying stylet probing behavior of hemipterans, and blood-feeding arthropods. These results are applied to understanding pesticide action, host plant resistance, and vector-pathogen-host interactions...
April 28, 2018: Journal of Economic Entomology
Roman Kuc
This paper describes phase-sensitive and phase-insensitive processing of monaural echolocation waveforms to generate target maps. Composite waveforms containing both the emission and echoes are processed to estimate the target impulse response using an audible sonar. Phase-sensitive processing yields the composite signal envelope, while phase-insensitive processing that starts with the composite waveform power spectrum yields the envelope of the autocorrelation function. Analysis and experimental verification show that multiple echoes form an autocorrelation function that produces near-range phantom-reflector artifacts...
April 2018: Journal of the Acoustical Society of America
Laurent Lamaignère, Kévin Gaudfrin, Thierry Donval, Jeanyves Natoli, Jean-Michel Sajer, Denis Penninckx, Roger Courchinoux, Romain Diaz
Forward pump pulses with nanosecond duration are able to generate an acoustic wave via electrostriction through a few centimeters of bulk silica. Part of the incident energy is then scattered back on this sound wave, creating a backward Stokes pulse. This phenomenon known as stimulated Brillouin scattering (SBS) might induce first energy-loss, variable change of the temporal waveform depending on the location in the spatial profile making accurate metrology impossible, and moreover it might also initiate front surface damage making the optics unusable...
April 30, 2018: Optics Express
Jin Li, Tao Pu, Jilin Zheng, Yunshan Zhang, Yuechun Shi, Huatao Zhu, Yuandong Li, Xin Zhang, Guowang Zhao, Yuke Zhou, Xiangfei Chen
Photonic generation of linearly chirped microwave waveforms (LCMWs) using a monolithic integrated three-section laser is experimentally demonstrated in this work. All three sections of the laser cavity, including the front DFB section, phase section and rear DFB section, have the same active layer, which can avoid the butt-joint re-growth process. The gratings in both DFB sections are fabricated by the Reconstruction Equivalent Chirp technique, which can significantly decrease the difficulties in realizing precise grating structure...
April 16, 2018: Optics Express
Neal A Hessler, Kazuo Okanoya
The avian song system is a group of brain areas specialized for vocal learning and production of song. A major cortical control area, HVC, projects both to a motor output circuit and to a striatal area in the anterior forebrain pathway. These projections are made by two groups of neurons, with mainly distinct roles in either programming vocal production or regulating vocal plasticity. In order to distinguish these two types of projection neurons in singing birds, we recorded unit activity in HVC of anesthetized birds, while stimulating in the anterior forebrain nucleus Area X...
April 27, 2018: Behavioural Brain Research
Yong Qing Lu, Yang Dai, Xiu Ying Yu, Fu-Lan Yu, Shou Lin Jiang, Zong Yuan Zhou, Fa Jun Chen
In recent years, the two issues of climate change including elevated CO2 etc., and resistance of transgenic Bt crops against non-target insect pests have received widespread attention. Elevated CO2 can affect the herbivorous insects. To date, there is no consensus about the effect of elevated CO2 on the suck-feeding insect pests (non-target insect pests of transgenic Bt crops). Its effects on the suck-feeding behavior have rarely been reported. In this study, CO2 levels were set up in artificial climate chamber to examined the effects of ambient (400 μL·L-1 ) and double-ambient (800 μL·L-1 ) CO2 levels on the suck-feeding behavior, growth, development, and reproduction of the non-target insect pest of transgenic Bt rice, brown planthopper, Nilaparvata lugens...
February 2018: Ying Yong Sheng Tai Xue Bao, the Journal of Applied Ecology
Zhenhua Wei, Zhen Liu, Bo Peng, Rui Shen
Interrupted sampling repeater jamming (ISRJ) is an effective way of deceiving coherent radar sensors, especially for linear frequency modulated (LFM) radar. In this paper, for a simplified scenario with a single jammer, we propose a dynamic electronic counter-counter measure (ECCM) scheme based on jammer parameter estimation and transmitted signal design. Firstly, the LFM waveform is transmitted to estimate the main jamming parameters by investigating the discontinuousness of the ISRJ's time-frequency (TF) characteristics...
April 8, 2018: Sensors
Michael B Sano, Richard E Fan, Kai Cheng, Yamil Saenz, Geoffrey A Sonn, Gloria L Hwang, Lei Xing
PURPOSE: To compare the intensity of muscle contractions in irreversible electroporation (IRE) treatments when traditional IRE and high-frequency IRE (H-FIRE) waveforms are used in combination with a single applicator and distal grounding pad (A+GP) configuration. MATERIALS AND METHODS: An ex vivo in situ porcine model was used to compare muscle contractions induced by traditional monopolar IRE waveforms vs high-frequency bipolar IRE waveforms. Pulses with voltages between 200 and 5,000 V were investigated, and muscle contractions were recorded by using accelerometers placed on or near the applicators...
April 6, 2018: Journal of Vascular and Interventional Radiology: JVIR
Chung-Ki Wong, Qingfei Luo, Vadim Zotev, Raquel Phillips, Kam Wai Clifford Chan, Jerzy Bodurka
BACKGROUND: In simultaneous EEG-fMRI, identification of the period of cardioballistic artifact (BCG) in EEG is required for the artifact removal. Recording the electrocardiogram (ECG) waveform during fMRI is difficult, often causing inaccurate period detection. NEW METHOD: Since the waveform of the BCG extracted by independent component analysis (ICA) is relatively invariable compared to the ECG waveform, we propose a multiple-scale peak-detection algorithm to determine the BCG cycle directly from the EEG data...
March 31, 2018: Journal of Neuroscience Methods
Yu Fang, Zhongwei Jiang, Haibin Wang
Obstructive sleep apnea (OSA) affecting human's health is a kind of major breathing-related sleep disorders and sometimes leads to nocturnal death. Respiratory rate (RR) of a sleep breathing sound signal is an important human vital sign for OSA monitoring during whole-night sleeping. A novel sleep respiratory rate detection with high computational speed based on characteristic moment waveform (CMW) method is proposed in this paper. A portable and wearable sound device is used to acquire the breathing sound signal...
2018: Journal of Healthcare Engineering
Ji H Hong, Sung W Jung
The identification of epidural space with loss of resistance (LOR) is commonly performed. But it lacks specificity. Epidural pressure waveform analysis (EPWA) provides a simple confirmative adjunct for LOR. If the needle is located within the epidural space, measurement of the pressure at its tips shows a pulsatile waveform. Previous studies demonstrated satisfactory sensitivity and specificity of EPWA. However, success or failure of epidural injection was confirmed by the pinprick test, which is limited for patients in the setting of the pain clinic...
March 2018: Medicine (Baltimore)
Pedro David Arini, Sergio Liberczuk, Javier Gustavo Mendieta, Martín Santa María, Guillermo Claudio Bertrán
Background and Objectives: The extensive use of electrocardiogram (ECG) recordings during experimental protocols using small rodents requires an automatic delineation technique in the ECG with high performance. It has been shown that the wavelet transform (WT) based ECG delineator is a suitable tool to delineate electrocardiographic waveforms. The aim of this work is to implement and evaluate the ECG waves delineation in Wistar rats applying WT. We also describe the ECG signal of the Wistar rats giving the characteristics of its spectrum among other useful information...
2018: Computational and Mathematical Methods in Medicine
Matthew E L Hardy, Eleftheria Pervolaraki, Olivier Bernus, Ed White
We investigated the steepened dynamic action potential duration (APD) restitution of rats with pulmonary artery hypertension (PAH) and right ventricular (RV) failure and tested whether the observed APD restitution properties were responsible for negative mechanical restitution in these myocytes. PAH and RV failure were provoked in male Wistar rats by a single injection of monocrotaline (MCT) and compared with saline-injected animals (CON). Action potentials were recorded from isolated RV myocytes at stimulation frequencies between 1 and 9 Hz...
2018: Frontiers in Physiology
Bo Hyun Kim, Jae Sik Jang, Yong Seop Kwon, June Hyung Kim, In Joo Kim, Chang Won Lee
BACKGROUND: We evaluated the ability of brachial ankle pulse wave velocity (baPWV) to predict coronary artery stenosis (CAS) in patients with type 2 diabetes, and compared the predictive power of baPWV to that of well-known cardiovascular disease (CVD) risk calculators. METHODS: The study group included 83 consecutive patients over 30 years old with type 2 diabetes who complained of vague chest discomfort. An automatic pulse waveform analyzer was used to measure baPWV...
March 2018: Endocrinology and Metabolism
Hollie A Ryan, Shinji Hirakawa, Enbo Yang, Chunrong Zhou, Shu Xiao
Nanosecond electric pulses are an effective power source in plasma medicine and biological stimulation, in which biophysical responses are governed by peak power and not energy. While uniphasic nanosecond pulse generators are widely available, the recent discovery that biological effects can be uniquely modulated by reversing the polarity of nanosecond duration pulses calls for the development of a multimodal pulse generator. This paper describes a method to generate nanosecond multiphasic pulses for biomedical use, and specifically demonstrates its ability to cancel or enhance cell swelling and blebbing...
April 2018: IEEE Transactions on Biomedical Circuits and Systems
Peter A White
This paper reviews proposals that conscious perception consists, in whole or part, of successive discrete temporal frames on the sub-second time scale, each frame containing information registered as simultaneous or static. Although the idea of discrete frames in conscious perception cannot be regarded as falsified, there are many problems. Evidence does not consistently support any proposed duration or range of durations for frames. EEG waveforms provide evidence of periodicity in brain activity, but not necessarily in conscious perception...
April 2018: Consciousness and Cognition
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