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Background Transcutaneous stimulation of the auricular branch of the vagus nerve (AB-VNS) is a potentially noninvasive, inexpensive, and safe approach for vagus nerve stimulation that suppresses the induction and duration of atrial fibrillation and reduces sympathetic nerve outflow in healthy humans. Researchers have not determined whether AB-VNS affects ventricular arrhythmias. Objective To evaluate the antiarrhythmic effects of noninvasive AB-VNS on ventricular arrhythmias induced by myocardial infarction (MI). Methods and results Twelve beagle dogs were randomly divided into the following two groups: a AB-VNS group (coronary artery occlusion and noninvasive AB-VNS) and a control group (coronary artery occlusion but without AB-VNS). We examined spontaneous ventricular arrhythmias, ventricular electrophysiological properties, and cardiac function in conscious dogs. Morphology, fibrosis, and ultrastructures were also assessed. AB-VNS significantly reduced the occurrence of spontaneous ventricular arrhythmias, including isolated premature ventricular complexes, ventricular couplets, ventricular bigeminy, ventricular trigeminy, and ventricular tachycardia. AB-VNS effectively increased ventricular electrical stability, including significantly prolonged ventricular effective refractory periods, decreased the dispersion of effective refractory period, enhanced the ventricular fibrillation threshold, and decreased the maximum slope of the monophasic action potential duration restitution curve. AB-VNS treatments alleviate ventricular interstitial fibrosis after MI. However, cardiac function was not improved, and MI-induced ultrastructural changes in the myocardium were not reversed by 4 weeks of AB-VNS. In addition, AB-VNS for 4 weeks resulted in mild mitochondrial swelling within the neuronal axons of the auricular vagus fiber. Conclusions Noninvasive AB-VNS reduces the occurrence of spontaneous ventricular arrhythmias in conscious dogs with MI. AB-VNS increases ventricular electrical stability and alleviates ventricular interstitial fibrosis induced by MI.

We propose and evaluate six different methods by using the fusion of 2D radar and passive sensors to track the 3D target in Cartesian coordinates. The evaluated results of these methods are examined in various metrics to confirm the stability and accuracy of algorithms. In this paper, numerical simulation and mathematical expressions are presented to expose that the estimation in our model are equivalent to those ones in fusion of 3D radar and IR sensor also.

In order to improve effect of weak signal de-noising, an improved threshold de-noising function based on the characteristics of soft-threshold function and hard-threshold function which are used to estimate wavelet coefficients is proposed in this paper. This new function can obtain better threshold, which is between the hard threshold and soft threshold by adjusting the parameters. It not only overcomes the disadvantage of the segmentation of hard-threshold function effectively, but also solves the constant deviation and discontinuous derivative of soft-threshold function. The simulation results demonstrate the effectiveness of the algorithm.

This paper proposes an improved blind separation algorithm based on natural gradient. The traditional natural gradient algorithm is improved by a suitable nonlinear activation function and auto-adaptive step length. The effectiveness of the proposed algorithm can be shown in the simulation of speech signals separation.

The losses of power transmission and distribution reach up to 7% of electric power output in our country, which decrease the electric utilization ratio and cause enormous waste of electrical power. As a great energy consumer in transmission and distribution industry, it has been urgent affairs to reduce transformer losses for our energy-saving work. With the development of transformer manufacturing technology, amorphous core transformers have replaced present massively-used SII and the under series of transformers, which have become a hot subject discussed in the field. This paper, based on theoretical analysis and TOC, systematically and thoroughly diagnoses the energy saving potential of Nanning transformers through investigating the transformer service conditions in 6 counties and 6 districts in Nanning and offers data support and decision basis for the government's large scale extension of amorphous core transformers.

The key technologies of SCADA (supervisory control and data acquisition) system in manufacturing enterprises, such as the database and client server structure, are discussed in this paper. The realization of the system is also given. Finally, the authors forecast the development trend in this field.

Objectives To investigate the molecular basis of L-type calcium channel in adult and aged canine. Methods Two groups of mongrels were investigated: seven adult and ten-year-old canines. The effective refractory period (ERP) of HRA, coronary sinus proximal (CSp), coronary sinus distal (CSd), left atrial appendage (LAA), right atrial appendage (RAA), left superior pulmonary vein (LSPV), left inferior pulmonary vein (LIPV), right superior pulmonary vein (RSPV) and right inferior pulmonary vein (RIPV) were measured in sequence at an atrial pacing of S1S2. We measured the mRNA gene and protein expression levels of L-type calcium channel α1 subunit (CaV1.2), sarcoplasmic reticulum Ca2+-ATPase (SECRA2), Calpain-I, ryanodine receptor (RyR2) in atrial myocardial tissue from two groups. Results The ERP of RAA and CSp were significantly longer in the aged than in the adult dogs (p

Purpose The present study aims to investigate the molecular basis of L-type voltage dependent calcium channel (LVDCC) in adult and aged canine. Methods The action potential duration (APD 90 ), amplitude of action potential plateau, I Ca-L peak current density were of LVDCC, recorded by patch clamp technique. The mRNA gene and protein expression levels of α1c subunit (CaV1.2), sarcoplasmic reticulum Ca 2+ -ATPase (SECRA 2 ), Calpain-I, ryanodine receptor (RyR 2 ) were detected by semi-quantitative RT-PCR. Results I Ca-L peak current density was (−14.04±0.82 pA/pF), in adult group compared with (−8.11±0.54 pA/pF, p 90 ) of aged group was significantly decreased. The mRNA gene expression levels of CaV1.2 was significantly lower in the aged dogs (0.9±0.35) than in the adult dogs (2.38±0.4, p 2 was significantly higher in the aged dogs (4.39±4.68) than in the adult dogs (1.49±1.69, p 2 and calpain I in two groups; The protein expression levels of CaV1.2 were significantly lower in the aged dogs than in the adult dogs (0.13±0.10 vs 0.29±0.12, p 2 was significantly higher in the aged dogs than in the adult dogs (0.18±0.21 vs 0.08±0.36, p 2 and Calpain I in two groups. Conclusion These data suggest that the change of mRNA and protein expression of CaV1.2 and RYR 2 of LVDCC may serve as the molecular basis of I Ca-L remodeling respectively in aged dogs. This plays an important role in the predisposition to developing atrial fibrillation (AF) due to ageing.

2 μm InGaSb/AlGaAsSb strained quantum wells and a tellurium-doped GaSb buffer layer were grown by molecular beam epitaxy (MBE). The growth parameters of strained quantum wells were optimized by AFM, XRD and PL at 77 K. The optimal growth temperature of quantum wells is 440 °C. The PL peak wavelength of quantum wells at 300 K is 1.98 μm, and the FWHM is 115 nm. Tellurium-doped GaSb buffer layers were optimized by Hall measurement. The optimal doping concentration is 1.127 × 1018 cm−3 and the resistivity is 5.295 × 10−3 Ω·cm.

Objective The purpose of the present study was to investigate the safety and efficacy of circumferential pulmonary vein isolation (CPVI) and CPVI combined with complex fractionated atrial electrograms (CFAEs) ablation for atrial fibrillation (AF). Methods Data from 112 patients who underwent CPVI and CPVI combined with CFAEs ablation in our hospitals were collected. Results The mean total procedure times were (112±47 min vs 136±54 min) for CPVI and CPVI combined CFAEs ablation. The mean total fluoroscopy times were (34±18 min vs 40±12 min) CPVI and CPVI combined CFAEs ablation. There was no difference in pulmonary vein isolation in CPVI and CPVI combined CFAEs ablation (44±12 min vs 46±9 min, p=0.52). During a mean follow-up of 36 months, the procedure success rate (73.9% vs 66.7%, 65.2% vs 62.1%, 58.7.% vs 57.6%, p Conclusion CPVI and CPVI combined CFAEs ablation are safe and effective for treatment of AF. CPVI combined CFAEs ablation was better than CPVI in attaining stable sinus rhythm in the majority of patients during up to 36 months of follow-up.

InAs/GaSb superlattice (SL) midwave infrared photovoltaic detectors are grown by molecular beam epitaxy on GaSb(001) residual p-type substrates. A thick GaSb layer is grown under the optimized growth condition as a buffer layer. The detectors containing a 320-period 8ML/8ML InAs/GaSb SL active layer are fabricated with a series pixel area using anode sulfide passivation. Corresponding to 50% cutoff wavelengths of 5.0 mu m at 77 K, the peak directivity of the detectors is 1.6 x 10(10) cm.Hz(1/2) W-1 at 77 K.

InAs/GaSb superlattice (SL) short wavelength infrared photoconduction detectors are grown by molecular beam epitaxy on GaAs(001) semi-insulating substrates. An interfacial misfit mode AlSb quantum dot layer and a thick GaSb layer are grown as buffer layers. The detectors containing a 200-period 2ML/8ML InAs/GaSb SL active layer are fabricated with a pixel area of 800 x 800 mu m(2) without using passivation or antireflection coatings. Corresponding to the 50% cutoff wavelengths of 2.05 mu m at 77K and 2.25 mu m at 300 K, the peak detectivities of the detectors are 4 x 10(9) cm.Hz(1/2)/W at 77K and 2 x 10(8) cm.Hz(1/2)/W at 300 K, respectively.

We investigate the molecular beam epitaxy growth of GaSb films on GaAs substrates using AlSb buffer layers. Optimization of AlSb growth parameter is aimed at obtaining high GaSb crystal quality and smooth GaSb surface. The optimized growth temperature and thickness of AlSb layers are found to be 450 degrees C and 2.1 nm, respectively. A rms surface roughness of 0.67 nm over 10 x 10 mu m(2) is achieved as a 0.5 mu m GaSb film is grown under optimized conditions.

Researchers from the US and China apply optimization methodology to the problem of scheduling a bulk-pickup-and-delivery fleet for a fleet operation in Shanghai. Preliminary observations on the problem and on the differences and similarities in the application of MS/OR in China and the US are offered.