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Carbapenem-resistant Klebsiella pneumoniae (CRKP) seriously threaten the efficacy of modern medicine with a high associated mortality rate and unprecedented transmission rate. In this study, we isolated a clinical K. pneumoniae strain DY1928 harboring blaNDM-1 from a neonate with blood infection. Antimicrobial susceptibility testing indicated that DY1928 was resistant to various antimicrobial agents, including meropenem, imipenem, ceftriaxone, cefotaxime, ceftazidime, cefepime, piperacillin-tazobactam, and amoxicillin-clavulanate. S1 nuclease-pulsed field gel electrophoresis (S1-PFGE), southern blot and conjugation experiment revealed that the blaNDM-1 gene was located on a conjugative plasmid of IncA/C2 type with a 147.9 kb length. Whole-genome sequencing showed that there was a conservative structure sequence (blaNDM-1-ble-trpF-dsbD) located downstream of the blaNDM-1 gene. Multilocus sequence typing (MLST) classified DY1928 as ST25, which was a hypervirulent K. pneumoniae type. Phylogenetic analysis of genomic data from all ST25 K. pneumoniae strains available in the NCBI database suggested that all blaNDM-1 positive strains were isolated in China and had clinical origins. A mouse bloodstream infection model was constructed to test the virulence of DY1928, and 11 K. pneumoniae strains homologous to DY1928 were isolated from the feces of infected mice. Moreover, we found that DY1928 had a tendency to flow from the blood into the intestine in mice and caused multiple organ damage. To our knowledge, this is the first study to report an infection caused by blaNDM-1-positive ST25 K. pneumoniae in the neonatal unit. Our findings indicated that stricter surveillance and more effective actions were needed to reduce the risk of disseminating such K. pneumoniae strains in clinical settings, especially in neonatal wards.

As a major byproduct of direct coal liquefaction, coal liquefaction residue (CLR) waste is environmentally harmful but also valuable. Considering environmental and economic efficiency, exploiting these wastes as electrodes for new generation energy storage devices will increase the economic value and decrease environmental pollution synchronously. In this regard, CLRs are used to prepare carbon nanofibers film for supercapacitors via electrospinning followed by HNO3 preoxidization, air stabilization, and carbonization processes for the first time. The influences of HNO3 preoxidization over the formation of fiber morphology, textural structure, surface chemistry, and electrochemical performance are investigated. Our work demonstrates that HNO3 preoxidization can enhance the content of the heteroatom of the as-spun nanofibers and promote the polymerization of the asphaltene (CLRA) molecular during air stabilization, leading to the changes of the thermal behaviors and thus avoiding the fibers melting success...

To assess the efficacy and safety in 105 patients with seasonal Influenza in Beijing, the mixture prepared with Chinese medicines follows the treatment regimen of releasing exterior cold and clearing interior heat.Total 330 patients with seasonal influenza were enrolled and randomly and averagely divided into the Chinese herbal medicine, the western medicine and the Chinese patent medicine group. They were treated with Chinese medicine Oseltamivir Phosphate Capsules and the Scattering Wind and Resolving Toxins Capsules. The main efficacy indicators were the antifebrile onset time and recovery time of body temperature. The efficacy and safety of the mixture was scientifically evaluated. Comparisons of several variables were analyzed.Median antifebrile onset time of the Chinese herbal medicine group was significantly shorter than the western medicine group (P0.05) and the Chinese patent medicine group (P0.05). The median antifebrile recovery time of the Chinese herbal medicine group was significantly shorter than the Chinese patent medicine group (P0.05). The groups evaluated by TCM symptom pattern effect, both the Chinese herbal medicine group and Western Medicine group were better than the Chinese patent medicine group (P0.05). The disappearance rate of main symptoms and some minor symptom patterns of the Chinese herbal medicine group were higher than the other 2 groups.The mixture of releasing exterior cold and clearing interior heat could significantly shorten the fever time with safety.

Modification process has been conducted on commercial nuclear graphite IG-110 (Toyo Tanso Co., Ltd., Japan) by impregnation and pyrolysis of polycarbosilane (PCS) solution for getting the modified IG-110 (M-IG-110) coated by dense SiC coating for molten salt reactor. The microstructure and properties of graphite were systematically investigated and compared before and after the modification process. Results indicated that the M-IG-110 possessed of more excellent integrated properties including molten salt barrier property and oxidation resistance than bare IG-110 due to the filling effect of SiC particles in the pores of M-IG-110 and dense SiC coating adhering to the surface of M-IG-110. The fluoride salt infiltration amount of M-IG-110 under 5 atm was only 1.1 wt%, which was much less than 14.9 wt% for bare IG-110. The SiC coating derived from PCS exhibited remarkable compatibility with graphite substrate under high temperature and gave rise to excellent oxidation resistance of M-IG-110.

In adaptive systems, the least mean square error (LMS) adaptive algorithm is widely used. The variable step size LMS algorithm (SVSLMS) based on the Sigmoid function has greatly improved the convergence speed, and the normalized LMS algorithm is stable Sexual performance has certain advantages. Therefore, improvement is made on this basis, the SVSLMS algorithm is normalized, and the iteration speed is increased by changing the iteration factor, and the stability of the algorithm is also improved. This paper uses MATLAB simulation tools to verify the superiority of the new algorithm. Finally, the improved algorithm is applied to beamforming to estimate the azimuth of arrival of the simulated sound source signal at the partial discharge point of the submarine power cable.

To achieve software output domain coverage is a challenge to the functional testing of security-critical software. This paper proposed a test data generation method based on artificial immune algorithm using intelligence testing approach. Firstly, based on the analysis of the software output domain coverage problem, we gave the basic idea of applying artificial immune algorithm to software testing, and introduced the general steps of the algorithm. Secondly, we designed the main operators of the artificial immune algorithm, such as antibody affinity evaluation operator, antibody concentration evaluation operator, immune selection operator, clone operator, mutation operator, etc., to achieve the automatic generation of software test data. Finally, several software was used to verify the validity of the method. The verification results show that the method achieves the software output domain coverage, and its effect is better than the genetic algorithm and random testing.

In order to accurately measure the temperature of power plant boiler, a new algorithm of time delay was proposed based on third correlation and phase transform weighting on the basis of the research of traditional cross-correlation method and generalized cross-correlation. Small peaks can be weakened with the help of phase transform weighting and the addition of exponential coefficient β. The simulation result shows that the PHAT-β algorithm based on third correlation can accurately measure the value of time delay estimation compared with first correlation, second correlation and traditional third correlation, so as to improve the accurancy of temperature of power plant boiler.

Ultrasonic signals will be generated when high voltage equipment is partially discharged. In order to de-termine the location of partial discharge, the time difference between ultrasonic signal and sensor can be used. In this paper, Alpha stable distribution is used to model noisy ultrasonic signals collected during actual partial discharge, and a nonlinear transformation-covariant time difference estimation method is proposed. Firstly, the signal-to-noise ratio can be improved to a certain extent by preprocessing the noisy signal based on the arctangent nonlinear transformation. Then, the covariant correlation function is used to measure the similarity of the two signals arriving at the sensor, and according to the position of the peak value of the covariant correlation function, the time difference information of signal arrival is obtained. On the basis of theoretical analysis, the experimental results of computer simulation are discussed and summarized. Com-pared with generalized correlation method and covariant algorithm, the proposed method is more suitable for TDOA estimation of PD ultrasonic signals in low SNR and impulsive noise environment.

In the process of evaluating the quality of a batch of 125S casing for oil and gas wells, it was found that the mechanical properties of different casing bodies in the same batch were significantly different, and the fluctuation range of yield strength was up to 60 MPa. The steel pipe with the lowest yield strength was not satisfied according to the technical standards. In order to study the causes of the uneven tensile properties, the chemical composition analysis, tensile tests, Charpy impact tests, Rockwell hardness tests and metallographic analysis were investigated for the two casings of this batch. Through the analysis of the test results, it is found that the chemical composition and metallographic structure of this batch of casing were conforming to with the design requirements, and the materials possessed high toughness. The problem of non-uniform performance of this batch casing was generated from the heat treatment stage during the production process. The excessive tempering temperature caused the reduction of material strength.

Porous molybdenum disulfide (MoS2) has a wide range of applications in catalysis and adsorption. Herein, we developed a new method, namely the sulfuration of fibrous NaNH4Mo3O10·H2O in hydrothermal-gas phase system at 120 °C using thiourea as sulfur source to prepare fibrous and porous MoS2, and then the sulfidization products were further calcined at 550 °C for increasing specific surface area. This method can keep the original fibrous shape of the precursors, and avoid the disintegration of precursors in sulfuration reaction under hydrothermal or high temperature gas phase conditions. The new material has perfect pore structure (˜123.7 m2/g of specific surface area, ˜0.375 cm3/g of pore volume). It shows excellent adsorption abilities for methyl orange (MO) in acidic solution and desorption properties in alkaline solution. The obtained porous MoS2 has also the advantages of easy recovery through ordinary vacuum filtration due to its micron particle size, therefore, it has wide application prospects in catalysis and adsorption.

Partial discharge of power equipment is one of the common faults in power systems. How to quickly and accurately determine the location of partial discharge is a problem that needs to be solved in practice. The signal arrival time difference estimation technique in signal processing is one of the effective methods to solve this problem. When the power equipment is partially discharged, an ultrasonic signal is generated. Therefore, the local discharge can be positioned according to the ultrasonic signal, however, the traditional signal arrival time difference estimation methods are not ideal for the actual low signal-to-noise ratio and narrow-band ultrasonic signals. In this paper, an improved correlation coefficient waveform comparison time difference estimation algorithm based on complete ensemble empirical mode decomposition with adaptive noise（CEEMDAN）, threshold denoising is proposed, referred to as CEEMDAN-TDE. Firstly, according to the characteristics of the actual ultrasonic signals, the double-exponential decay oscillation model is used to model the partial discharge ultrasonic signals, and Gaussian white noises are added as the interference signals. secondly, the CEEMDAN threshold denoising is used to improve the signal-to-noise ratio of the partial discharge signals; thirdly, the cross-correlation coefficient is calculated, then the arrival time difference can be obtained by comparing the waveforms of the correlation coefficients, and the partial discharge location information is known. The computer simulations of the CEEMDAN-TDE method, and the generalized correlation method, LMS method, and correlation coefficient waveform comparison method estimation are performed. Experimental results show that the estimating performance in arrival time difference of proposed method, CEEMDAN-TDE, is better than the other three methods’ under low SNR and narrowband. The CEEMDAN-TDE method has the hopeful more application in practice.

Noise control is a research topic that has been widely concerned for in recent years. When a noise space has a certain volume and/or with complex channel, the method of active noise control (ANC) can be used to reduce or eliminate noise interference. The main channel delay in the active noise control system has an important impact on the performance of the ANC system, however, the traditional method, such as filtered-x least mean square algorithm (FxLMS), lacks the estimation of the main channel delay. This results that the system output cannot be accurately synchronized. Especially in the case of time-varying delay, the effect is less desirable. In this paper, the correlation time delay estimation is combined with FxLMS. A method to improve the performance of active noise control system (CTDE-FxLMS) is proposed based on time delay estimation. In CTDE-FxLMS method, the correlation time delay estimation is used to calculate the main channel delay, and the frequency response of the main channel is calculated by FxLMS. CTDE-FxLMS method improves the synchronization accuracy between the system output and the original noise in the time domain and the frequency domain. The computer simulation results show that the CTDE-FxLMS method has better noise reduction effect than the FxLMS method both the conditions of fixed delay and time-varying delay.

In this paper Cu-WS2-graphite-WS2 nanotube composites were fabricated by powder metallurgy hot pressing method. The effect of current polarity on the wear rates and contact voltage drops of the composites were investigated using a brush-on-slip ring tribometer rubbing against Cu-5 wt.% Ag alloy ring in air and vacuum, respectively. The worn surfaces of the composites were analyzed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Surface profile curves of the worn tracks were measured using the surface profiler. The results demonstrated that the current polarity has a significant effect on the wear rates and contact voltage drops of the composites in both air and vacuum conditions. Positive brush possesses a higher wear rate compared with the negative brush in the air atmosphere since the electrical field direction activates oxidation at the positive brush surface while inhibits oxidation at the negative brush surface. Except for the regular wear losses, the combined effect of molten metal bridge erosion and arc erosion cause the positive brush to lose extra material and the negative brush to gain extra material, so the positive brush shows a higher wear rate in the vacuum condition. The contact voltage drop of the positive brush is lower than that of the negative brush in the air atmosphere, but contrarily, the positive brush shows a higher contact voltage drop in the vacuum condition.

Performance of time delay estimation (TDE) algorithm directly affects effect of electromechanical equipment fault sound source positioning based on TDE. Designing more accurate algorithm based proper models of background noise and fault sound can improve accuracy of localization. Firstly, this paper analyzes the characteristics of noise and fault sound of external central air conditioners, then, models environmental noise using Alpha distribution. Finally, Analyzes measured data and preprocess them, realize the more appropriate modeling of environmental noise and eliminate operating noise sources interference. This study has a guiding significance in large-scale mechanical and electrical equipment failure sound source signal modeling, and is helpful to research on TDE algorithm.

The influence of ?-irradiation on properties of METGLAS 2605S2 and FC3-1 Fe78B13Si9 has been investigated by M?issbauer spectroscopy and bending test. The ductility and orientation of magnetization were changed by ?-irradiation. They probably correlated with the change of microscopic free volume and release of stress in the ribbon, respectively.

The basic NEMO protocol results in a sub-optimal route between Mobile Network Node (MNN) and Correspondent Node (CN) .This paper provides a mechanism based on DHCP Prefix Delegation (DHCPPD) to enable Mobile Network Node (MNN) to perform route optimization with CNN which has basic MIPv6 support .The goal is to use DHCPPD to assign Care-Of-Address (COA) to MNN , MNN can bind with Correspondent Node (CN) with basic MIPv6 support [3]. It effectively reduce unnecessary large travelling route and overhead, thereby enhance the performance. The solution is effective for both single NEMO and nested NEMO for which we will deploy DHCP replay mechanism as extension, and has a better performance than the basic NEMO protocol.

In view of defects of tradition chips used for conference systems, such as poor performance and higher prices, this paper proposes the technical solution to use DSP technology to design and realize the multi-party conference system, and describes detailed designs and specified realization methods. With stable performance and requiring much lower costs, the product is now being extensively applied in Chinese railway and military systems and achieving favorable economic and social benefits.

An amorphous phase of Ni/Ti bilayer system is formed by solid state reaction and inn beam mixing. The results of TEM cross sectional photograph show that the diffusion results in the amorphous phase formation, Ni is the dominate diffusion species, and the ion beam bombardment enhances Ni diffusion.