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In this paper, microphone array technology was used to monitor the dynamic pulsed GMAW process. At first, the splash sound signal is successfully separated out based on FastICA blind signal separation algorithm, and its frequency domain energy distribution is mainly concentrated in the high frequency band of 6000−8000 Hz. Through time and frequency domain analysis, it is found that the short-time energy of 500−1000 Hz band of observed signal and the short-time energy of splash signal can identify the burn-through defects well, furthermore the ratio of them can be used as a robust feature because of its high sensitivity and anti-interference performance. Since the splash sound signal is a characteristic signal separated by microphone array, it is shown that the abundant dynamic information provided by microphone array can better assist in the identification and monitoring of welding defects compared to a single microphone. In order to solve the serious imbalance problem between positive and negative samples, the logistic regression and BP neural network model are improved based on the machine learning method. The experimental results show that the recognition accuracy of the optimization models have been greatly improved, even could reach 99.6 %.

Porcine circovirus 3 (PCV3) is a recently identified virus that is associated with reproductive failure, porcine dermatitis and nephropathy syndrome, and multi-systemic inflammation. To investigate the molecular epidemic characteristics and genetic evolution of PCV3 in northern China, a commercial TaqMan-based real-time quantitative PCR kit was used to detect PCV3 in 435 tissue specimens collected from pigs with various clinical signs from 105 different swine farms in northern China. The results showed that 48 out of 105 (45.7%) farms and 97 out of 435 (22.3%) samples tested positive for PCV3. Of the 97 PCV3-positive samples, 80 (82.5%) tested positive for other pathogens. PCV3 was found more frequently in pigs with reproductive failure than in those with other clinical signs. This study is the first to detect PCV3 in Tianjin. The complete genome sequences of six PCV3 isolates and the capsid (Cap) protein gene sequences of 11 isolates were determined. Based on the predicted amino acids at positions 24 and 27 of the Cap protein and their evolutionary relationships, the 17 PCV3 strains obtained from northern China and 49 reference strains downloaded from the GenBank database were divided into four major groups (3a-3d). An analysis of selection pressure and polymorphism indicated that the PCV3 Cap protein seems to be evolving under balancing selection, that the population is in dynamic equilibrium, and that no population expansion occurred during the study period. Our results provide new information about the molecular epidemiology and evolution of PCV3.

Porcine deltacoronavirus (PDCoV) is a recently identified coronavirus that causes intestinal diseases in neonatal piglets with diarrhea, vomiting, dehydration, and post-infection mortality of 50-100%. Currently, there are no effective treatments or vaccines available to control PDCoV. To study the potential of RNA interference (RNAi) as a strategy against PDCoV infection, two short hairpin RNA (shRNA)-expressing plasmids (pGenesil-M and pGenesil-N) that targeted the M and N genes of PDCoV were constructed and transfected separately into swine testicular (ST) cells, which were then infected with PDCoV strain HB-BD. The potential of the plasmids to inhibit PDCoV replication was evaluated by cytopathic effect, virus titers, and real-time quantitative RT-PCR assay. The cytopathogenicity assays demonstrated that pGenesil-M and pGenesil-N protected ST cells against pathological changes with high specificity and efficacy. The 50% tissue culture infective dose showed that the PDCoV titers in ST cells treated with pGenesil-M and pGenesil-N were reduced 13.2- and 32.4-fold, respectively. Real-time quantitative RT-PCR also confirmed that the amount of viral RNA in cell cultures pre-transfected with pGenesil-M and pGenesil-N was reduced by 45.8 and 56.1%, respectively. This is believed to be the first report to show that shRNAs targeting the M and N genes of PDCoV exert antiviral effects in vitro, which suggests that RNAi is a promising new strategy against PDCoV infection.

Many effective image-based imaging algorithms are available for detecting and locating the defects for plate-like structures. The discrete ellipse imaging algorithm is widely applied in plate-like structures. However, the scattering-wave extracted by the baseline subtraction may easily be impacted by noise and the reflect wave from boundary, which significantly reduces the signal-to-noise (STN) of the scattering wave, and then leads to the degrading of imaging accuracy. To enhance the STN and improve imaging accuracy, a novel method of zero-signal filling is used in the discrete ellipse imaging in this paper. To verify its effectiveness, the imaging experiment with a circular sparse array has been conducted. The experimental results show that the method can effectively resolve the signal delay and enhance the STN of the scattering wave. The imaging accuracy can be improved obviously by this method and the defect can be located accurately.

With the development of sensor technology and the increasing demand of industrial upgrading, high intelligence and high-precision processing and manufacturing is the development trend of the future automation industry. As the eye of industry, sensor is the core part of intelligent industrial system. Line-structured light sensor is widely used in automatic manufacturing because of its non-contact, high-robust, and high-precision characteristics. This paper analyzes the latest application and research of line-structured light sensing technology in the industrial application of workpiece object detection and positioning, geometric profile measurement, three-dimensional reconstruction. It is found that line-structured light can provide more convenient advantages for high-precision measurement in automatic production line with its non-contact advantage. Through the feature extraction and reconstruction of the surface profile, the accurate estimation of the three-dimensional shape and coordinates of the workpiece can be realized, which lays the theoretical foundation and practical basis for further realizing the automatic manufacturing.

Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus-associated diseases in swine, the most common of which are postweaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). To investigate the prevalence and genetic diversity of PCV2 in Hebei Province, Northern China, from 2016 to 2019, a total of 448 suspected cases of PCV2 infection were studied, and 179 samples were positive for PCV2. A pathological and histopathological examination suggested PCV2 to be cause of the observed lesions. Phylogenetic analysis showed that four genotypes were prevalent in Hebei Province: PCV2a, 2b, 2d, and 2e. Analysis of PCV2 strains using RDP4 and SimPlot showed that there were genetic recombination events among PCV2 strains in Hebei Province. A total of 3284 serum samples were screened by ELISA, and the positive rate of PCV2 antibodies was 73.9% (2428/3284). This study provides a scientific reference for the prevention and treatment of PCV2 in Hebei Province.

To understand the seismic behaviors of concrete columns confined by corroded stirrups, low-reversed cyclic loading tests were carried out on eight corroded reinforced concrete columns to study their mechanical characteristics and failure mechanisms. The influence on seismic performance indicators such as bearing capacity, hysteresis characteristics, ductility, strength degradation, stiffness degradation, and energy dissipation was analyzed comparatively based on parameters such as stirrup diameter and stirrup-spacing changes. The experimental results showed that the restraint of concrete provided by corroded stirrups is reduced, which leads to a decline in seismic performance, and with increasing stirrup corrosion, the failure limit displacement of columns decreases. The pinch phenomenon of the hysteresis curve gradually increases, the attenuation degree of strength and stiffness increases, and the ductility and energy-dissipation capacity is reduced, while the accumulated energy increases under the same control displacement. A method for predicting the lateral strength of reinforced concrete columns confined by corroded stirrups is presented based on the axial-shear-flexure interaction approach for conventional concrete columns, with modifications to consider the effect of stirrup corrosion. There was good agreement is achieved between the test results and theoretical values.

2351 working face with paste backfill method of Daizhuang coal mine in eastern China is selected as engineering background, bearing characteristics of backfill body and supporting intensity of hydraulic support during coal pillar mining with paste backfill are researched. Researches show that: Even if the confining pressure is only 1 Mpa, the paste backfill material shows typical plasticity hardening. The overlying strata of working face with paste backfill method include fractured zone, continuous deformation zone, don’t include caved zone. The distribution of vertical stress above the backfill body is not a horizontal line nor presents saddle-shaped, but presents a wave distribution. The stress above backfill body does not appear abrupt change but tends to be increasing at first and stable at last. The mechanical model of roof stability during coal pillar mining with paste backfill is built, and the mechanics related formula of supporting intensity is also concluded. The hydraulic supports used in 2351 working face can control the roof subsidence effectively, but the efficiency of hydraulic supports is lower, which should be optimized properly.

The low-consuming wireless sensor network is becoming more and more popular; this essay drafts a proposal for wireless sensor network system design. The proposal describes detailed hardware and software designs of sensor node. With a feature of self-organized and self-adaptive, the system remains keep good communication even the location of network node changes. This system is applicable to synchronized monitoring on water pollution in rivers, lakes, springs and oceans.

Commonly used commercial simulation software SYSNOISE and ANSYS is run on a single machine (can not directly run on parallel machine) when use the finite element and boundary element to simulate muffler effect, and it will take more than ten days, sometimes even twenty days to work out an exact solution as the large amount of numerical simulation. Use a high performance parallel machine which was built by 32 commercial computers and transform the finite element and boundary element simulation software into a program that can running under the MPI (message passing interface) parallel environment in order to reduce the cost of numerical simulation. The relevant data worked out from the simulation experiment demonstrate that the result effect of the numerical simulation is well. And the computing speed of the high performance parallel machine is 25 ~ 30 times a microcomputer.

Kako bi se analizirao utjecaj kuta, broja i raspona raspukline na čvrstoću i karakteristike akustičke emisije (AE) stijenske mase, postavljen je jednoosni kompresijski model uzoraka stijene uz primjenu PFC2D računalne platforme za protok mikro čestica. Metodom pokusa i pogreške određeni su originalni parametri stijene, u modelu su unaprijed izvedene raspukline različitih kutova, brojeva i razmaka, te je provedeno ispitivanje na pritisak metodom praćenja pomaka. Tlačna čvrstoća, modul elastičnosti i vremenske karakteristike AE uzoraka stijene su se povećali, smanjili te ponovo povećali kako se povećavao kut raspukline. Karakteristike AE kod raspukline kutova 0°, 15°, 30° i 90° bile su u skladu s onima kod originalnih uzoraka stijene, dok su se kod kuta raspukline od 45° ÷ 75° pojavile relativno diskretne karakteristike AE. Veći broj raspuklina podudarao se u nižoj jednoosnoj tlačnoj čvrstoći, modulu elastičnosti i intenzitetu AE. Međutim, nije došlo do značajne promjene u vremenu i veličini deformacije. Tlačna čvrstoća i intenzitet signala AE uzoraka stijene porasli su s povećanjem razmaka raspukline, ali se to nije pokazalo na pokazivaču vremena AE. Jednoosna ispitivanja kompresije provedena su numeričkom simulacijom kako bi se izbjegli nehomogeni i diskretni učinci ispitivanja u zatvorenom prostoru i točno odredio utjecaj kuta, broja i razmaka raspukline na čvrstoću i karakteristike AE stijenske mase. Rezultati mogu pomoći kod određivanja odgovarajućih kriterija za predviđanje nestabilnosti stijenske mase., To analyse the influence of joint angle, number and spacing on the strength and acoustic emission (AE) characteristics of rock mass, the uniaxial compression model of rock specimens was established using the micro particle flow PFC2D software platform. The intact rock parameters were determined via trial and error, joints with different angles, numbers and spacing were prefabricated in the model, and a compression test was performed using the displacement control method. The compressive strength, elastic modulus, and AE time characteristics of the rock specimens increased, decreased, and then increased again along with increasing joint angle. The AE characteristics at joint angles 0°, 15°, 30° and 90° were consistent with those of the intact rock specimens, while the 45° ÷ 75° joint angle showed relatively discrete AE characteristics. A larger number of joints corresponded to lower uniaxial compressive strength, elastic modulus, and AE intensity. However, the time and strain range of the obvious AE were not significant. The compressive strength and AE signal intensity of the rock specimens increased along with joint spacing, but the AE triggering time did not show obvious changes. Uniaxial compression tests were performed via numerical simulation to avoid the non-homogeneous and discrete effects from the indoor test and to reflect accurately the influence of joint angle, number, and spacing on the strength and AE characteristics of rock mass. The results can help in generating reliable criteria for predicting the instability of engineering rock mass.

In order to research the mechanical properties of the backfill cream-body under engineering conditions in the coal mine, the uniaxial compression test of backfill cream-body with different ages abtained from the filling locale of Daizhuang coal mine is conducted with MTS815.03 rock test system. The characteristics of backfill cream-body in the limited space and a certain environment are studied. Research shows that, the strength of backfill cream-body is high, but coagulability is bad and the discreteness of mechanical properties is different; Uniaxial compressive strength is 2.3 ~ 13.17 MPa and the average is 5.436 MPa; The elastic modulus is very low ,which is only 53.66 ~ 2614.35 MPa and the average is 645.14 MPa. The deformation is bigger when absorbing load; Poisson's ratio is low, which is only 0.0001 ~ 0.2112 and the average is 0.0265, which indicates that the backfill cream-body doesn't need the space of transverse deformation when bearing compression deformation; The mechanical parameters of backfill cream-body with different ages are fitted and regressed. Test results is important to control surface mining subsidence effectively, liberate the coal resources under buildings, railways and waterbodies and protect the ecological environment.

In order to study permeability characteristics of low-strength coal under higher confining pressure, complete stress-strain permeability characteristics tests on 15# coal of Shanxi Province Qinshui Basin are conducted. Research shows that 15# coal manifests obvious plastic under 6MPa confining pressure whose uniaxial compressive strength is 7.43MPa; The saturated specimen’ permeability reduces provisionally during initial compression as the native fractures are closed; With the specimen compressed continuingly, new fractures appear and those fractures connect, then the permeability rapidly increase; But while the soft coal enters into plastic-flow state, because that the specimen becomes more homogeneous and fractures have closed, the permeability greatly reduces lower then the initial value. Research result has important guiding significance for reasonable retaining waterproof pillar in deep mining.

On the basis of the field measurement, the characteristics of advance strata behavior are analyzed in the past filling working face and the advance support method is optimized in the roadway. The practical measure researches show that, because the paste filling supports the overlying strata of the goaf availably, the strata behaviors of 2351 paste filling working face in Daizhuang coalmine are not obvious; And the protective pillar bears a little load, The strata behaviors in non-production side are smaller than that in production side. The overlying strata gravity mainly acts on the coal wall in front of the face and the paste filling in the goaf. The value and main influence range of advance stress in front of the face is quite small and the main influence range is less than 15m. According to the advance strata behavior characteristics of the paste filling working face, the advance support of the track roadway is changed from 3 rows to 2 rows. And the support length of each row reduces from 20m to 15m. The advance support after optimizing can reduce the labor intensity greatly and improve the working efficiency of backfill mining.

The creep test of the No. 3 coal seam of Daizhuang Coal Mine is carried. Based on the experiment results, the creep support effect of deep pillar is analyzed with LS-DYNA. The results show that the circumferential initial creep stress of the tested coal is 3.061MPa and the circumferential initial creep stress is far below the axial initial creep stress which is 7.020MPa. In addition, the creep strength is 9.3266MPa and the creep coefficient is 0.6472. According to the test results, the creep support effect of deep strip pillar can be simulated excellently with LS-DYNA. Stress and deformation in simulated strip pillar show evident rheology. Many changes will take place in the stable situation of pillar after the working face mining. Under the effect of the overlying strata, this pillar turns into steady creep state after 15~16 months, then the pillar is able to maintain long-term stable state.

In this paper, in order to get the mechanical properties of the different ratio similar material models and resolve the matching problem of pressure sensor and measured similar material, according to the similarity theories, the repeated loading tests on different ratio similar models were performed by multi-stage loading. This paper got the stress-pressure curve and the failure strength of each model. Test results show that there are significant differences in the matching abilities between different ratio similar materials and pressure sensors, and the matching abilities between different models of the same ratio and pressure sensors also have some differences. The matching ability between similar material and pressure sensor should be detected, so as to correct the experimental data. Test results also show that different ratio similar materials have stable and different mechanical properties. The mechanical properties of the similar material can be adjusted appropriately by changing the ratio. The mechanical properties of different ratio similar materials should be tested before the similar material simulation test.

In order to determine the characteristics of noise source accurately, the noise distribution at different frequencies was determined by taking the differences into account between aerodynamic noises, mechanical noise, electrical noise in terms of in frequency and intensity. Designed a least squares wavelet with high precision and special effects for strong interference zone (multi-source noise), which is applicable to strong noise analysis produced by underground mine, and obtained distribution of noise in different frequency and achieves good results. According to the results of decomposition, the characteristics of noise sources production can be more accurately determined, which lays a good foundation for the follow-up focused and targeted noise control, and provides a new method that is greatly applicable for testing and analyzing noise control.

In this work, the widely used chevron corrugated-plate heat exchanger was simulated, and the three-dimensional temperature, pressure, and velocity fields were obtained. From the temperature field we can see that in the first zone, the temperature gradient increases gradually and get the maximum; in the central of the flow, the temperature gradient becomes smaller again. The highest temperature appears around the upper port, while the lowest temperature appears in the cold fluid inflow around the lower port. From the pressure field, we can see that the fluid pressure is gradually reduced along the flow direction. From the flow field, no matter the fluid inflows or outflows the port, there is a marked “dead zone” departed from the corrugated side of the port, where the fluid flow rate is very low. The fluid flows along the side of the port and appears a minor's “bias” (uneven-distributed) phenomenon. Meanwhile, it can be seen that a large number of contact points are distributed in the chevron corrugated-plate heat exchanger. In addition, the simulated results are compared with the experimental values and found that trends of the outside temperature are consistent with those of pressure drop, and experimental values were similar to those of simulated values.

Background and objective Phosphodiesterase type-5 inhibitors (PDE-5 inhibitors) have been suggested as a first-line drug for treating pulmonary arterial hypertension (PAH). The aim of present meta-analysis was to fully evaluate the efficacy and safety of treating PAH with PDE-5 inhibitors, focusing on the improvement of 6-min walk distance (6MWD). Methods Studies were identified from The Cochrane Library, EMBASE, and PUBMED databases. We calculated odds ratios (OR) for dichotomous data and weighted mean differences with 95% confidence intervals (CI) for continuous data. Results Six studies with a total of 1056 patients (729 patients in PDE-5 inhibitors treatment group and 327 patients in placebo group) were included. All-cause mortality rate in the control group and PDE-5 inhibitors group was 2.6% and 0.7%, respectively. In an average of 12.3-week follow-up, PDE-5 inhibitors treatment was associated with a 71% reduction in mortality (OR 0.29; 95 %CI 0.07–1.15; P = 0.08), and increased 6MWD by 40.17 m, improved NYHA functional class and hemodynamic parameters. As for monotherapy and combination therapy patients, 6MWD has improved by 48.94 m and 21.75 m, respectively. Conclusions The results of present meta-analysis suggest that treatment with PDE-5 inhibitors improves the 6MWD, clinical symptoms, hemodynamic parameters, and a tendency of survival benefits. In patients treated with PDE-5 inhibitor monotherapy, the 6MWD significantly increased when compared to combination therapies.

The present paper aimed at the question that the beam cross-section changes according to the rotation of concave grating during the measuring process, and the appropriate supplement to the principle of the program was done. The appropriate supplement to the principle lay the foundation for the derivation of the beam cross-section k(theta), and the whole analytical expression of changes factor of the beam cross-section k (theta) for concave grating was derived. Because of the relationship between the theoretical values and the factors which affect the diffraction efficiency measuring accuracy was nonlinear, the quadratic nonlinear regression analysis was introduced and the compensating formula was established. The results show further correction to diffraction efficiency measurements for concave grating, the range of differences between the compensated values and the theoretical values was reduced from +/- 2.5% to less than +/- 0.3%, compared with the linear regression analysis, and the quadratic nonlinear regression analysis significantly reduces the variation between the compensated values and the theoretical values, which further ensures the accurate measurement of the diffraction efficiency for concave gratings. The compensating process is embedded in the measurement program; this method is strongly real-time, which can satisfy the requirements of simple operation, testing speediness and preciseness.

Cold compaction behaviour of metal powders was analyzed using Shima, Fleck and Cam-Clay models. The Cam-Clay model reflects a very different plastic deformation mechanism for porous materials when compared with other two models. Brown's triaxial compressive experimental data (loading states: 1:1:1, 1:0.4:0.4, 1:0:0) were employed as the arbiter to these plastic models. It is very clear that only the Cam-Clay model can simulate well all experimental data under different loading states for iron and copper powders, while Shima or Fleck model can not. Therefore the Cam-Clay model is recommended to be used to analyze cold compaction densification process of metal powders.

To analyze the efficacy and safety of intra-aortic balloon pump (IABP) therapy in patients with acute myocardial infarction(AMI) based on the meta-analysis.Eligible published randomized controlled clinical research (RCT) were retrieved in the Pubmed, EMBase, Cochrane, China biological medical literature, Wanfang, VIP and CNKI database from 1980 to April 2, 2012. The analysis was performed with the software of RevMan 5.1.Thirteen RCTs with 1958 patients (AMI with IABP therapy, n = 970,without IABP therapy, n = 988) were included. The 30-day mortality between the two groups was similar (RR = 0.77, 95%CI 0.58-1.03, P = 0.08), but the 30-day mortality in the cardiac shock subgroup was significantly lower in IABP group than in without IABP group (RR = 0.65, 95%CI 0.44-0.97, P = 0.04). The 6-month mortality was significantly lower in IABP group than in without IABP group (RR = 0.72, 95%CI 0.55-0.94, P = 0.02). The incidence of major bleeding was significantly higher in IABP group than in without IABP group (RR = 1.43, 95%CI 1.16-1.75, P0.01).IABP therapy is effective to reduce earlier mortality post AMI, particularly for patients with cardiac shock.

The present paper analyzed the influence of the pinhole diameter, grating parameters, CCD pixel size, prism parameters, system aberrations and found that the first three are the main factors, and then deduced the mutual restraint relationship among them. On this basis, a portable high-resolution echelle spectrograph was designed. Applying this design, aberration was fully corrected and spectral resolution achieved the demand. With the Hg lamp calibrated and restored, the actual resolution gets up to 0.038 nm which is significantly better than target (0.05@200 nm), while the ordinary grating spectrometers need 500 mm focal length to achieve this resolution. From this result, the advantages of the portable echelle spectrograph are fully demonstrated.

All-solid-state lithium secondary batteries are strongly desired as novel candidates for EV and HEV power source, since safety issue is much more serious in large-sized lithium batteries for such applications. Replacement of combustible non-aqueous liquid electrolytes with solid electrolytes is considered to be the ultimate solution to this issue. Inorganic solid-electrolytes have several advantages over liquid, polymer or gel electrolytes, including better thermal and chemical stability, preventing safety hazard issues for energy storage systems with high energy densities. First of all, a lithium superionic conductor exhibiting sufficient ionic conductivity at room temperature (RT) is required in order to develop safe rechargeable lithium batteries. Generally, the electrolytes can only be used in chemical power source devices with lithium ionic conductivity around 10-3 S/cm at RT. For oxide type lithium ion solid electrolytes, the ionic conductivity, mechanical and chemical stability of lithium ion conductor can be improved through the optimization of material formula, morphology and single crystal size control as well as formation of composite electrolyte. Oxide solid electrolytes with high stability, high density (density is greater than 96%), high ionic conductivity (~ 10-3 S/cm at RT), uniform single crystal size and shape controllable has been developed. Meanwhile, a series of products, including powder, density ceramic disk and large size block, etc., has realized large-scale production. For sulfide type lithium ion solid electrolytes, the ionic conductivities for binary and ternary sulfide solid electrolytes could be as high as 2.06×10-3 and 8.27×10-3S/cm at room temperature. The details for the properties of solid-state electrolytes are listed in Table 1. Recently, different sulfide electrolytes has been applied in all-solid-state lithium batteries with LiNi0.8Co0.15Al0.05O2 (NCA) positive materials. Two different solid electrolytes (Li3.25Ge0.25P0.75S4: 2.03×10-3 S cm-1; Li10GeP2S12: 8.27×10-3 S cm-1) are used,and Li-In alloy is used as negative electrode. As shown in Fig. 1, NCA/sulfide electrolytes/Li-In cell exhibits good charge and discharge capacity, although the discharge capacity is lower compared with traditional liquide battery. The lower discharge capacity is attributed to the higher interface resistance. This experiment proves that Ni-based exhibits excellent reversible intercalation-deintercalation ability. Besides, M-NCA is prepared by surface modification on NCA. All-solid-state batteries with M-NCA positive electrode are assemblyed by the same method, and the discharge capacity is dramatically increased to 150 mAh/g, which is due to the strong decrease of interface resistance. References: Yicheng Tao, Shaojie Chen, Deng Liu, Gang Peng, Xiayin Yao, Xiaoxiong Xu, J. Eclectrochem. Soc., (2016) DOI: 10.1149/2.0311602jes. Yanran Zhao, Chuan Wu, Gang Peng, Xiaotian Chen, Xiayin Yao, Ying Bai, Feng Wu, Shaojie Chen, Xiaoxiong Xu, J. Power Sources 301 (2016) 47-53. Yao Xiayin, Huang Bingxin, Yin Jingyun, Peng Gang, Huang Zhen, Gao Chao, Liu Deng, Xu Xiaoxiong, Chinese Physics B , (2015) Accepted. Invited Review. Bingxin Huang, Xiayin Yao, Zhen Huang, Yibiao Guan, Yi Jin, Xiaoxiong Xu, J. Power Sources , 284 (2015) 206-211. Jingyun Yin, Xiayin Yao, Gang Peng, Jing Yang, Zhen Huang, Deng Liu, Yicheng Tao, Xiaoxiong Xu, Solid State Ionics , 274 (2015) 8-11. Figure 1

Echelle spectrograph is a new type of high-resolution, high-precise spectrograph, and its resolution can be up to tens of thousands to hundreds of thousands. In this case, a little error of the structure will affect the resolution and precision greatly, so an accurate adjustment is of importance for the echelle spectrograph. According to the design features, the present paper discusses the adjustment method for echelle spectrograph. This is an uncomplicated, quick method, and adapts to mini, airproof structure of echelle spectrograph. Using this method, the actual state is consistent with the design result. The result of wavelength calibration is given out, and the error is less than 0.002 nm, which satisfies the requirement of the system.

It is important for the echelle spectrograph to acquire the exact positions of the spots in the two-dimension spectra image, which directly influence the precision of spectral analysis. With the target of high resolution, which is 15 000 in the echelle spectrograph being discussed, the acquired positional error must be less than 0.03 mm-which equals 2 pixels. According to the characters of the two-dimensional spectra, a position-acquiring method for the signal spots based on the centroid computing algorithm was put forward. Applying this method, the signal spots were distinguished from the noise spots and their positions can be acquired accurately and swiftly, with the positional error less than 2 pixels and wavelength error 0.02 nm, which satisfy the requirements of the echelle spectrograph.

The efficacy of rate and rhythm control strategies for treating atrial fibrillation (AF) patients was analyzed in this meta-analysis.Eligible trials were searched in MEDLINE, the Cochrane Library, the Clinical Trials, the Chinese VIP database up to May 31, 2010. Ten prospective randomized control trials with 7876 patients (rate control n = 3932, rhythm control n = 3944) were included for final analysis.All cause mortality (5.3% vs. 5.0%; OR: 1.03; 95%CI: 0.84 - 1.26; I(2)25%) and incidence of worsening heart failure (3.81% vs. 3.61%; OR: 1.04; 95%CI: 0.80 - 1.36; I(2)50%) were similar between the two groups. Subgroup analysis showed that all cause mortality (3.6% vs.1.9%; OR: 1.89; 95%CI: 1.01 - 3.53; I(2)25%) and rate of worsening heart failure (2.3% vs. 0.3%; OR: 5.6; 95%CI: 1.44 - 21.69; I(2)25%) were significantly higher in rate control group than in rhythm control group in patients with age65 years. Thromboembolic events (1.49% vs. 1.46%; OR: 1.02, 95%CI: 0.71 - 1.48) and bleeding events (1.78% vs. 1.73%; OR: 1.02, 95%CI: 0.70 - 1.49) were similar between rhythm control and rate control groups while rehospitalization rate was significantly lower in rate control group than in rhythm control group (17.56% vs. 22.98%; OR: 0.37, 95%CI: 0.19 - 0.71).This meta-analysis shows that rhythm control strategy is superior to rate control strategy for AF patients with age65 years in terms of reducing all cause mortality and incidence of worsening heart failure.

Summary Background The Child-Pugh score, the model for end-stage liver disease (MELD) score, and the occurrence of cirrhosis-related complications are independent prognostic predictors used in the assessment of chronic liver diseases. Objectives The objectives of this study were to determine the best prognostic scoring system, and to create a combined method to predict the prognosis of liver cirrhosis more accurately. Methods We retrospectively reviewed 435 cirrhotic patients from January 2009 to June 2010 and evaluated their short- and medium-term survival. Child-Pugh, MELD and its advanced scoring systems were computed for each patient. The sensitivity and specificity of these scoring systems were analyzed and their validity was assessed using concordance (c)-statistics in predicting the prognosis of cirrhotic patients. Results Overall, 107 patients died within 6 months and 150 patients died within 1 year. The clinical and biochemical characteristics, cirrhosis-related complications, and the scores were significantly different among the survivors and patients who died. The largest area under the receiver operating characteristic curve was 0.741 for the integrated MELD (iMELD) at 6 months and 0.713 for iMELD at 12 months, indicating that iMELD was the best scoring system tested. Given this result, we created a new scoring system that combined iMELD and an index of cirrhosis-related complications, called iMELD-C. This novel system had c indexes of 0.758 for the 6-month survival and 0.746 for the 1-year survival. Conclusions The iMELD-C score is a better predictor of both short- and medium-term survival in patients with cirrhosis.

To investigate the feasibility of transferring p21 gene into lung tissue with recombinant adenovirus with full-length cDNA of p21 inserted in the Wistar rat model of pulmonary hypertension (PAH) induced by left-to-right shunt, study the expression of the desired gene in vivo, find if overexpression of desired gene can inhibit pulmonary hypertension.With full-length cDNA of p21 transfected HEK293 cells with clonfectin, and was packed, amplified in order to obtain the high-titer recombinant adenovirus (AdCMV-p21). The infection titer was determined by TCID50 method and was diluted into 1.67 x 10(8) pfu/L. Wistar rats were randomly allocated to control group (n = 10), model group (n = 15), test group (n = 10) and test control group (n = 10). In model group and test group left-to-right shunt pulmonary hypertension was developed by using cuff technique. AdCMV-p21 was transfected into test group and test control group using tracheal inhalation. The mPAP, mRVP and RVHI were measured and compared between every two groups. The left lung was immunohistochemically stained to observe the result of transfection. The right lung was HE stained to observe morphological changes in arteria pulmonalis and calculate WT%.The mRVP, mPAP and WT% in model group and test group were significantly higher than those in control (P0.05), which suggested that the rat model of PAH was established successfully. Brown spots in the nucleus of VSMCs of pulmonary artery were seen in test group and test control group, which indicated that AdCMV-p21 was transfected successfully. The rate of transfected cells in test group was (42.8 +/- 11.6)%, which was equal to that of test control group (P0.05). In test group, the mPAP was (20.06 +/- 3.40) mm Hg (1 mm Hg = 0.133 kPa), mRVP was (22.53 +/- 2.53) mm Hg, WT% was (30.8 +/- 3.5)%, which were significantly lower than those in model group (P0.05), but higher than those in control group and test control group (P0.05).The recombinant adenovirus could successfully carry p21 and transfect the lung tissue of PAH rat model, and full expression of p21. p21 gene could inhibit the development of PAH.

Multi-sensor information fusion (MSIF) technology, is being widely applied to the modern military field. For the sake of implementing effectively detection and rapid exact identification for the chemical agent in sea-battlefield, and applying MSIF technology in Naval Ships Chemical Detection (NSCD) field, the NSCD system based on the multi-sensor fusion model is built. At the same time, connecting the wavelet analysis with the neural networks organically, and based on the wavelet transfer and the neural networks, the system of the speedy features extraction and identification for chemical agent - the Neural Networks Distinguishing Chemical Agent (NNDCA) system - is founded. The model of the NNDCA by the returning neural networks with deviation unit and the method of the feature extraction for the chemical agent based on the wavelet analysis are established, the realization idea of the NNDCA system is put forward, and the hardware accomplishment and the software structure of the NNDCA system are discussed. Based on experiments, the experimental and simulated results show: it is feasible that the qualitative and quantitative analyses for the chemical agent with the NNDCA system based on the MSIF technology and the wavelet analysis. The method can remarkably heighten the accuracy and credibility of the measurement results, and the results are of repeatability.

Novel cone lasing emission is observed from a photonic crystal (PC) with graded layers, which is fabricated by two-beam holographic interference in dichromated gelatin. The cone lasing is composed of one lasing spot and one concentric lasing ring. The good agreement between the experimental results and a numerical simulation performed using the transfer matrix method demonstrates that this lasing ring is induced by the coupling between the band edge and minigap, which is represented as some oscillations near the band edge in the passband of the reflection spectrum. The cone lasing may be useful for multi-wavelength fluorescence detection since the dual-colour directional enhanced fluorescence can be achieved without the mutual interference of lasing modes. Moreover, this readily observable cone lasing provides a direct visualization of the dispersion relation of non-uniform PCs.

This study was designed to investigate the pathophysiological role of adrenomedullin (ADM) in congenital heart disease.Forty-eight children with congenital heart disease confirmed by cardiac echocardiography and catheterization were studied. The patients were divided into three groups on the basis of hemodynamic indices measured during cardiac catheterization: high pulmonary blood flow with (group 1) or without (group 2) pulmonary hypertension (mean pulmonary arterial pressure20 mmHg) and a cyanosis group (without high pulmonary blood flow) (group 3). Six children who recovered from Kawasaki disease were used as a Control group. Plasma ADM levels were measured by radioimmunoassay.The plasma ADM levels from the femoral vein were significantly higher than those from femoral artery in patients with congenital heart disease. The patients from group 1 and group 3 had higher plasma ADM levels (1.9 +/- 1.8 pmol/L and 2.4 +/- 1.3 pmol/L, respectively) than the controls (1.0 +/- 1.4 pmol/L; P0.01). Plasma ADM levels were significantly negatively correlated with mean systemic arterial pressure, oxygen saturation in mixed vein and oxygen saturation in systemic artery (r=-0.401, -0.562, -0.600, respectively; P0.01) but positively correlated with pulmonary vascular resistance (r=0.406; P0.01).Plasma ADM levels are increased in congenital heart disease with high pulmonary blood flow and hypertension or with cyanosis. Plasma ADM levels are related to pulmonary arterial resistance and hypoxemia. Increased ADM levels may play roles in reducing the pulmonary arterial resistance and alleviating hypoxemia in these patients.