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Background To assess the utility of routine postoperative laboratory tests for patients undergoing high tibial osteotomy (HTO) surgery. Methods The associations between clinical risk factors and postoperative clinical treatment were analyzed. Additionally, a logistic regression analysis was performed to detect independent risk factors for patients requiring postoperative clinical treatment. Results A total of 482 patients with symptomatic isolated medial compartment osteoarthritis from January 2015 to May 2020 were included in the present study and underwent examination by the full set of postoperative laboratory tests within 3 days after HTO surgery. However, only a small proportion of the patients with anemia (3.9 %), hypoalbuminemia (4.1 %), and abnormal serum potassium levels (3.5 %) required clinical intervention after surgery. Binary logistic regression analysis showed that the body mass index (BMI), preoperative hemoglobin level, estimated blood loss and operative duration were independent risk factors for postoperative blood transfusion in patients who underwent HTO surgery, and factors associated with albumin supplementation were female sex and preoperative albumin level. In addition, these results indicated that preoperative potassium was potential risk factor for patients who required potassium supplementation postoperatively. Conclusions Based on the analysis, we conclude that routinely ordering postoperative laboratory tests after HTO surgery is unnecessary. However, for patients with identified risk factors, routine postoperative laboratory tests are still needed.

The primary aim was to identify potential risk factors for early conversion to total knee arthroplasty (TKA) in patients with high tibial osteotomy (HTO) surgery. A retrospective study was conducted and 240 patients received HTO surgery between January 2008 and January 2014 were included in this study. The associations between different clinical factors and HTO survivorship were analyzed. A logistic regression analysis was performed to detect independent risk factors for HTO survivorship. The cut-off value, sensitivity and specificity of these independent factors were calculated by receiver operating characteristic (ROC) curve. In this study, thirty-five (14.6%) patients were early conversion to TKA within a 5-year follow-up. These results indicated that age, body mass index (BMI), preoperative Kellgren-Lawrence (K-L) grade and preoperative visual analogue scale (VAS) score were potential risk factors for HTO survivorship. The cut-off values of those factors were 60 years, 25.35 kg/m

Pancreatic cancer is an extremely malignant tumor with the lowest 5-year survival rate among all tumors. Pancreatic ductal adenocarcinoma (PDAC), as the most common pathological subtype of pancreatic cancer, usually has poor therapeutic results. Immune checkpoint inhibitors (ICIs) can relieve failure of the tumor-killing effect of immune effector cells caused by immune checkpoints. Therefore, they have been used as a novel treatment for many solid tumors. However, PDAC is not sensitive to monotherapy with ICIs, which might be related to the inhibitory immune microenvironment of pancreatic cancer. Therefore, the way to improve the microenvironment has raised a heated discussion in recent years. Here, we elaborate on the relationship between different immune cellular components in this environment, list some current preclinical or clinical attempts to enhance the efficacy of ICIs by targeting the inhibitory tumor microenvironment of PDAC or in combination with other therapies. Such information offers a better understanding of the sophisticated tumor-microenvironment interactions, also providing insights on therapeutic guidance of PDAC targeting. Video Abstract Supplementary Information The online version contains supplementary material available at 10.1186/s12964-021-00789-w.

Background: Has the arthroscopically assisted reduction of acute acromioclavicular (AC) joint separations with the tight-rope technique advantages over the clavicular hook plate fixation.Methods: A total of 518 patients with acute high grade AC joint dislocation received ligament reconstruction surgery between February 2015 and June 2017 were included in this study. Of these patients, 28 patients were treated with arthroscopic assisted fixation using Tight-Rope system. In order to compare the treatment results between Tight-Rope technique and clavicular hook plate fixation, each Tight-Rope technique group patients was matched with 3 controls that underwent clavicular hook plate fixation at the same period according to gender, age and diagnosis. Furthermore, the demographics and clinical characteristics were compared between the two groups.Results: All patients had clinical and radiological results available at 2 year or greater, they was statistically significant improvement in the constant score and VAS score at the end of follow up respectively (P < 0.001). Compared with clavicular hook plate group, patients treated with arthroscopic assisted fixation using Tight-Rope system were incurred significant statistically lower skin incision, hospitalization time and estimated blood loss (p

To explore microbial mechanisms of straw-induced changes in CO2, CH4, and N2O emissions from paddy field, wheat straw was amended to two paddy soils from Taizhou (TZ) and Yixing (YX), China for 60 d under flooded condition. Illumia sequencing was used to characterize shift in bacterial community compositions. Compared to control, 1–5% straw amendment significantly elevated CO2 and CH4 emissions with higher increase at higher application rates, mainly due to increased soil DOC concentrations. In contrast, straw amendment decreased N2O emission. Considering CO2, CH4, and N2O emissions as a whole, an overall increase in global warming potential was observed with straw amendment. Total CO2 and CH4 emissions from straw-amended soils were significantly higher for YX than TZ soil, suggesting that straw-induced greenhouse gas emissions depended on soil characteristics. The abundance of C-turnover bacteria Firmicutes increased from 28–41% to 54–77% with straw amendment, thereby increasing CO2 and CH4 emissions. However, straw amendment reduced the abundance of denitrifying bacteria Proteobacteria from 18% to 7.2–13% or increased the abundance of N2O reducing bacteria Clostridium from 7.6–11% to 13–30%, thereby decreasing N2O emission. The results suggested straw amendment strongly influenced greenhouse gas emissions via alerting soil properties and bacterial community compositions. Future field application is needed to ascertain the effects of straw return on greenhouse gas emissions.

Taking the dry coal shed of a coal-fired power plant as an example, the reticulated shell structure model of large-span three-centered cylindrical is established according to the specification requirements, and its design and optimization are carried out. It is to use the full stress design method to establish multiple comparison models by adjusting the thickness of the grid, to do the analysis and calculation for obtaining the comparison results of steel consumption, maximum vertical displacement and overall stability of different models, and then to determine the optimal span ratio of the large-span reticulated shell structure. All of these aim to draw relevant conclusions and provide reference for the design and optimization of similar large-span three-centered cylindrical reticulated shell engineering.

Background Large segmental bone defects can be repaired using the Masquelet technique in conjunction with autologous cancellous bone (ACB). However, ACB harvesting is severely restricted. α-calcium sulfate hemihydrate (α-CSH) is an outstanding bone substitute due to its easy availability, excellent biocompatibility, biodegradability, and osteoconductivity. However, the resorption rate of α-CSH is too fast to match the rate of new bone formation. The objective of this study was to investigate the bone repair capacity of the Masquelet technique in conjunction with isolated α-CSH or an α-CSH/ACB mix in a rabbit critical-sized defect model. Methods The rabbits (n = 28) were randomized into four groups: sham, isolated α-CSH, α-CSH/ACB mix, and isolated ACB group. A 15-mm critical-sized defect was established in the left radius, followed by filling with polymethyl methacrylate spacer. Six weeks after the first operation, the spacers were removed and the membranous tubes were grafted with isolated α-CSH, isolated ACB, α-CSH/ACB mix, or none. Twelve weeks later, the outcomes were evaluated by manual assessment, radiography, and spiral-CT. The histopathological and morphological changes were examined by H&E staining. The levels of alkaline phosphatase and osteocalcin were analyzed by immunohistochemistry and immunofluorescence staining. Results Our results suggest that the bone repair capacity of the α-CSH/ACB mix group was similar to the isolated ACB group, while the isolated α-CSH group was significantly decreased compared to the isolated ACB group. Conclusion These results highlighted a promising strategy in the healing of large segmental bone defect with the Masquelet technique in conjunction with an α-CSH/ACB mix (1:1, w/w) as they possessed the combined effects of sufficient supply and low resorption.

Background: Reducing cadmium (Cd) exposure in Cd-polluted areas in Asia is urgently needed given the toxic effects of Cd. The short-term and long-term benefits of lowering Cd exposure are unknown because of its long half-life in the body. Objectives: We aimed to investigate whether an intervention with low-Cd rice in a contaminated area of China reduced urinary Cd (UCd) levels and improved blood pressure and kidney function outcomes compared to no-intervention in consumers of high-Cd rice in the same region. Methods: 106 non-smoking subjects were divided into three treatment groups: the intervention group (replacing homegrown high-Cd rice with market low-Cd rice, n = 34), the non-intervention group (continue eating high-Cd rice, n = 36) and the control group (continued eating low-Cd rice they have been eating for years, n = 36). The intervention period lasted for almost 8 months, during which participants were visited on up to 4 occasions and UCd, systolic and diastolic blood pressure (SBP, DBP), kidney function biomarkers (β2-microglobulin and N-acetyl-β-D-glucosaminidase) were measured. Results: After 3 months, the geometric mean UCd in the intervention (Int) group decreased significantly by 0.32 μg/g (p = 0.007), while changes were not significant in the non-intervention (non-Int) group (0.13 μg/g, p = 0.95) or the control group (−0.01 μg/g, p = 0.52). UCd in the Int group remained lower than in the non-Int group but higher than in the Control group through the end of follow up. DBP in the Int group decreased significantly from 80 mm Hg at month three (p = 0.03) and stayed around 74 mm Hg for the remainder of the study. SBP also decreased in the Int group but with variations similar to those observed in the other two groups. The two kidney biomarkers showed variations without a clear pattern. Conclusion: This study suggested that UCd reflected both short-term (

Assessment of variety distinctness is important for both the registration and the protection of particular variety. However, the current testing system, which assesses a range of morphological characters of each pair of varieties grown side-by-side, is time-consuming and is not suitable for the assessment of hundreds of samples. The objective of this study was to develop a procedure for the assessment of wheat variety distinctness using simple sequence repeat (SSR) markers. A comparison between the molecular and morphological profile of 797 varieties was made. On the basis of the comparison, pairs of varieties with a genetic similarity value (GSV) ≤90% were deemed to be distinct, accounting for ∼85% of varieties assessed in wheat regional trials. For the remaining ∼15% of varieties, GSVs between different varieties were >90%, among which ∼35% were not distinct and the other ∼65% were distinct. Therefore, if given a GSV>90%, the pairs of varieties should be morphologically assessed in the field. To avoid any errors in the assessments, we proposed the elimination of contaminant plants from the sample before comparing the varietal genotypes, scoring of the genotype at each locus with a pair of allele numbers when constructing a molecular profile, and faithfully recording two alleles at a non-homozygous locus. To reduce the workload and cost, a three-grade markers comparison among varieties is suggested. In addition, 80 SSR markers and a technical procedure for assessment of wheat variety distinctness have been proposed. Based on the procedure, the distinctness assessment of ∼85% of all wheat varieties is completed in our laboratory annually. Consequently, total field assessment has been reduced considerably.

In this paper, a novel energy-efficient single-phase induction motor with three parallel-connected stator windings and two external capacitors has been proposed. By selecting the appropriate capacitors, the currents in the three windings will be approximately symmetric at rated load, thus high rated efficiency can be obtained. Based on the symmetrical component method, the condition for balanced operation is analyzed and the method for determining the requested capacitances is also obtained. The approach for calculating the steady-state performance is proposed.

Summary extract of heterogeneous multimedia documents is an important content and requirement of information management at the Internet era. Though some summary extract approaches have been proposed in recent years, in general they can only be used in a single-type media. More important is that the existed approaches of multimedia summary extract had no satisfactory effects, and can’t be brought into practice. Aiming at these problems, an approach based on folksonomy with incentive and quality assurance mechanisms is put forward. The proven folksonomy ensures the practicality of the approach, the incentive and quality assurance mechanisms avoid the innate problems of folksonomy: cold boot and inaccurate tagging. The experiment shows that the approach is reasonable and effective.

College students’ entrepreneurship should be combined with majors, based on professional knowledge as the core competitiveness, which is the basis of successful entrepreneurship. Dual embeddedness of social networks and industry networks is an inherent requirement to promote the growth of all entrepreneurial businesses. Features of embedded networks are different during different stages of college students’ entrepreneurship based on their professions. This determines college students’ entrepreneurial enterprises evolve from self-employed professional enterprises to professional enterprises and finally develop to product-innovative enterprises. This paper analyzes the effect of dual networks embeddedness on the growth of College Students' professional entrepreneurship from the perspective of embedded networks, making a few comments and suggestions in order to help students do professional entrepreneurship better and promote the growth of professional entrepreneurship.

The construction of wind power transmission line lagged behind the development of wind power generation, which leaded to the issue of wind curtailed and power rationing. In the wind power concentrated transmission process, using energy storage system(ESS) can relax transmission bottlenecks, and improve capability of wind power accommodation. An optimal method of using large scale ESS for relaxing wind power centralized transmission bottlenecks was presented in this paper. The comprehensive benefit was calculated by studying the relationship between wind power improved and optimization capacity configuration of ESS. Example shows that the proposed method can achieve more benefit of transmission line and more transmitted wind power than the traditional one without ESS in the same transmission line. ESS optimal power configuration is 46MW, and optimal capacity configuration is 421MWh. The decreased amount of wind curtailed is 983.6GWh with configuration ESS, saving 472100 tons of coal-fired power plans.

Children's blood lead levels and prevalence of lead poisoning in China are significantly higher than in developed countries, though a substantial decrease has been observed. Since 2011, strict lead control policies in lead-related industries have been implemented in China, but the success of these policies is unknown. In this study, we collected environmental samples, questionnaire data, and blood samples from 106 children from 1 to 14 years old, before and after implementation of lead-usage control policy in wire rope factories by local government in Zhuhang, Nantong in 2012. Results showed that, one year after the lead control, lead concentrations sharply decreased in both environmental and biological samples with a decrease of 0.43 μg/m3 (-84.3%) in ambient air samples, 0.22 mg/kg (-36.1%) in vegetable samples, 441.1 mg/kg (-43.7%) in dust samples, and 6.24 μg/dL (-51.5%) in childhood blood lead levels (BLL). This study demonstrates the success of lead control policies in promoting the prevention and control of childhood lead poisoning in Nantong, China.

Plastic materials are widely used in automobile manufacturing, and they have different mechanical characteristics at high and low temperature, which has a major influence on automobile safety. This paper mainly studies the relationship between elastic modulus and yield strength of plastic materials at high and low temperature, in order to predict the elastic modulus by the yield strength. On this basis, the values of the parameter of the constitutive model will be predicted to obtain the constitutive equation. The method meeting the precision is validated by the experiments. The method decreases experimental working, and provides technical support for product development as well.

A machine intelligence assistant BCI fusion navigation method of an outdoor mobile robot is put forward in view of the problem of BCI’s low signal-to-noise ratio, bad accuracy and long time delay. A vehicle navigation system based on BCI and dual laser radar is designed and implemented. First, improved angle potential field method based on dual laser radar is used for local path planning, then with navigation intention from BCI system, control commands are generated by fusion decision and used for driving a electric vehicle with modified mechanical system. Experiments show that the system can realize intelligent obstacle avoidance and human-machine collaborative navigation based on environmental obstacle information and brain machine interface control intention and it has higher accuracy, fault tolerance and robustness

Largely used in industry field, bearing is one of the most vulnerable components in an equipment. Owing to the complicated and nonlinear relationship between features and corresponding specific fault, it is less efficient to diagnosis the faults in tradition ways ,especially to deal with the fault of a mega machine. BP neural network whose strength is to solve the nonlinear problems makes it more precise and efficient to determine the fault of bearing. Conjugate gradient algorithm is proposed as the training method of the BP neural network. Compared with standard training method, conjugate gradient has the advantage of training speed and generalization ability, which is confirmed by the results of neural network model whose inputs are common bearing fault samples.

DC-DC converter is a kind of power conversion equipment. Electricity is the direct power for most mechanical industrial equipment currently. However, because of the diversity of mechanical industrial equipment, electricity should be transformed through power conversion equipment. This paper presents a DC-DC boost converter with PWM control method. The hardware and the structure of the core circuit is designed and the boost principle is interpreted. The detail of the configuration circuit around is described as well.

Diffusion is a key step in solar cells production. A new continuous diffusion furnace was put forward to promote productivity. However, the paddle system of continuous diffusion furnace, not same as that of traditional ones, has two paddles to handover silicon wafers. When loading silicon wafers, the paddle produces a deformation. The deflection has a significant influence on stability and efficiency. A deflection calculation method is presented as to a specific paddle in continuous diffusion furnace. The mechanical analysis and the finite element analysis are done. The test result of deformation shows that the calculation result is close to actual situation and meets the design requirements. The calculation results are valuable references in paddle system design.

Welding nuts are being used widely in automotive industry as threaded fasteners, its security and reliability requests are increasingly high. Accurate and quick detection results for surface quality can be obtained by using machine vision. Image edge detection by Canny operator has stronger acclimatization in anti-jamming and accurate edge localization. In order to suppress noise in maximum, an improved method is put forward to calculate the gradient of Canny operator, introducing Robert cross gradient in 3×3 neighborhood when calculating the gradient magnitude in finite difference method. The experimental results show that the improved Canny operator makes more effectively on the surface detection of welding nuts.

The mechanical and thermal response of elliptical head with multi-opening subjected to thermal loads, were carried out using ANSYS software. By dispersing the structure finite elements, the mechanical and fatigue behavior were discussed by APDL language following JB4732, and the result about stress evaluation and fatigue analysis are given, from the result, we can conclude that high first plus second stress and stress concentration may be formed at the intersection between center nozzle and elliptic, as well as between eccentric nozzle and elliptic. The structural discontinuity degree and temperature fluctuation has a big influence on stress concentration, as the most common, opening nozzle of a pressure vessel, the checking of dynamic and static of the structure, especially fatigue-checking are necessary.

The mechanical behavior of plastic material is dramatically sensitive to temperature. An method is proposed to predict the mechanical behavior of plastics for cars, ranging from low-temperature low temperature ≤-40°C to high temperature ≥80°C. It dominates the behavior of plastic material based on improved constitutive model in which the parameters adjusted by a series of tests under different temperatures. The method is validated with test and establishes the basis for research and development of plastic parts for automobile as well.

In order to solve the difficulty of low contrast feature extracting between labeled features and background, a new method combined the Hough transform and Canny algorithm is put forward for tensile test using the video extensometer, and a new algorithm edge detection is also obtained based on Canny an feature region tracking as well. The algorithm has proved to be a high positioning accuracy and computational efficiency in the test.

A three layer BP NN is created to design the cam. The data of cam contour ,which can be measured by CMM, has been used for the training where back propagation method is used.Advantage of solving nonliner problems gives BP netwok the ability to make out a more demand curve of cam. Taking advantage of its learning ability,NN model fits the actual cam contour gradually until the error fulfil the demand.Cam contour is ploted by Matlab,the result of which is better than cubic curve fitting,especially in the aspects of precise and velocity.

Based on the theory of target curve, a method of improving flatness target curve is proposed. The transverse temperature distributions of strip are measured and described with a biquadratic expression, and the statistics method is used to analyze the temperature distributions. Finally, the additional temperature stress compensation is calculated to improve the strip shape.

This paper researches on a method for on-line fault calculation based on expert system theory. The method improves traditional method of width precedence searching, and applies to form the node impedance matrix, which not only settles loop net but also advances calculation efficiency. To convenient for fault calculation, we process and identify the basic parameters and perform equivalent of 220kV external system. Moreover inbuilt fault calculation software has been realized, which can exchange data with SCADA system on-line.

In this paper, the spalling causes of backup rolls in a roughing mill of a hot strip rolling mill were investigated. The roughing mill withstood extreme service conditions with long service cycles for backup and work rolls, a large variety of the same width rolling campaigns, severe and non-uniform wear contours of backup and work rolls. Analysis of cyclic stress applied on backup rolls indicated that contact stress played a dominant role in rolling contact fatigue which led to spalling on the backup roll surface. A 3D finite element model of roll system was established and contact stresses between rolls in whole service periods of backup and work rolls were calculated. The simulation results showed that roll wear had significant impact on contact stress distribution. In particular, the severe and non-uniform U-typed wear contours of work rolls led to produce huge contact stress peak in two sides of the rolls, where existed large cracks by eddy current inspection of post-service backup rolls. Backup rolls stood thousands of times stress cycle in a service period, they were liable to fatigue damage in these areas. A new backup roll contour was developed to improve contact stress distribution and no spalling accidents were happened any longer after applied to the roughing mill.

This paper applies the theory of expert system to analysis for relay protection action based on PAS. And it also summarizes various rules according to the experience of operating personals and relay protection personals for several years. All these rules are suitable for 110kV and 66kV regional networks. This paper not only analyzes three-phase current protection, zero-sequence current protection, distance protection etc, but also discusses some special situations such as under voltage lockout over-current protection for transformer, remote backup protection etc.

By analyzing the two lightning accidents happening to a 500kV substation situated in the lightning-prone northeastern Guangdong Province, I conclude as follows, there should be some problem in the equipotential earthing of the secondary system of this substation. Specifically, the existing potential difference in the secondary equipment gave rise to the meltdown of it which finally caused the accident. In the context,I build the one-point earthing parallel system simulation model according to ATP graphic pretreatment program, then by using slope-ramp simulation I study the lightning current which leaked into the grounding grids of the substation.In conclusion, the application of high frequency signal mixed low frequency signal earth system in the secondary system and the equipotential bonding is key to preventing accidents.

In this paper, the transient characteristics of the permanent magnet synchronous motor based on the space vector pulse width modulation technology are researched in detail. Firstly, the mathematical model of the control system is established. Secondly, the simulation model based on MATLAB/Simulink is built. Thirdly, the transient simulation is implemented by the constructed model. It is proved that the mathematical model is valid and effective, which provides a theoretic base for the design of an actual permanent magnet synchronous motor control system.

We introduce an approach for making a ureteral tunnel with the aim of illustrating the importance of finding the tunnel dissection of the tissue spaces. The key to radical hysterectomy is identifying the tissue space that naturally exists between tissues rather than clamping a manual tunnel. For example, the urogenital sinus and Mullerian duct are very near each other; however, they never completely merge together. The method for finding the tunnel and avoiding the manual clamping of tunnels will maximally reduce intraoperative bleeding. Furthermore, the instructional significance of the surgery makes this technique worthy of promotion. Its main aspects include finding the gap, reducing or eliminating tunnel bleeding, and reducing collateral damage.

In International Union for the Protection of New Varieties of Plants member countries, assessment of wheat variety stability is a statutory requirement before new varieties are registered and plant breeders’ rights are granted. However, it is impossible to test the stability of varieties accurately and quickly, or to assess the stability of a large number of varieties in a short time based on the morphological traits defined by the national standard. The objective of this study was to establish method and procedure of wheat variety stability assessment using SSR markers as a replacement for morphological observations. In preliminary study, the methods to identify non-homozygous SSR loci and calculate the homozygous SSR loci ratio (SSR–HLR) of wheat varieties were established. On this basis, the genotypes at 347 molecular markers loci of 20 advanced lines demonstrated that SSR–HLRs were 84.7–94.8 % in the F4 lines, 96.1–99.4 % in the F5 lines, and ≥98 % in the F6 lines, respectively. Eighty of 347 markers with good polymorphism, stable PCR amplification, and high resolving power of genotyping were recommended to detect SSR–HLR for 633 wheat regional trial varieties. Comparing morphological observation, the varieties with SSR–HLR >95 % were deemed stable; the varieties with SSR–HLR

Affordable housing is an important part of China's housing security system. This policy is adapted to the actual situation of our country. The core advantage of the affordable housing is prices. It is to ensure the healthy development of affordable housing and a premise for the real role. How to make affordable housing for protection of the population can not only afford but also comfortable stay, developed pricing is the most important issue of its construction, it relates to the different interests of the class, a scientific and reasonable to take into account the different interests sectors of the pricing model. It helps to achieve social stability, improve the construction, regulatory and pricing mechanisms of affordable housing, and has a theoretical and practical significance.

The current two-dimensional (2-D) parameters for surface assessment (Ra and Pc) could not actually reflect functional properties of bearing and lubricant retention capabilities of steel sheets and rolls surface. Based on ARM9 development board, this paper has been working on secondary development of M1 mobile surface roughness meter, creating a model of calculating three-dimensional (3-D) functional characteristic parameters with 2-D profiles, and optimizing influence factors with Genetic Algorithms (GA). By comparing with measurement results by white-light interfering profile meter, the measurement error of the developed system is within10%, which was proved to be practical in the factory.

The objective of this study was to carry out a meta-analysis of the efficacy of gemcitabine+platinum agent regimens in the treatment of advanced biliary tract cancer (BTC). PubMed and Google Scholar were searched using the following combination of search terms: gemcitabine, oxaliplatin, cholangiocarcinoma, biliary, gallbladder, bile duct. Studies were eligible for inclusion in the meta-analysis if they were randomized trials on the use of gemcitabine plus a platinum agent for the treatment of advanced (unresectable or metastatic cancer) BTC. Outcomes of interest were response rate, overall survival, and progression-free survival. Pooled odds ratios/differences in median survival and 95% confidence intervals (CIs) were determined for each outcome. A total of 47 records were identified in the initial search. Ultimately, three open-label randomized trials (two phase 2 and one phase 3) met the eligibility criteria and were included in the meta-analysis. Two studies compared gemcitabine plus cisplatin with gemcitabine alone, whereas the other study compared gemcitabine plus oxaliplatin with fluorouracil-folinic acid. The total number of patients in the studies ranged from 54 to 410. The overall analyses revealed that all survival outcomes assessed were significantly more favorable for patients treated with gemcitabine plus platinum agents than for patients not treated with this combination. Response rates: odds ratio=2.639, 95% CI=1.210-5.757, Z=2.439, P=0.015; pooled difference in median overall survival=3.822 months, 95% CI=1.798-5.845 months, Z=3.702, P

This paper presents the data fusion survivability analysis model of wireless sensor network (WSN) based on stochastic Petri net (SPN). First, the definition of data fusion survivability is put forward, and the data fusion model of WSN is constructed. Second, the SPN modeling method of security events, which influences the WSN, is described. Lastly, simulation experiment proves the correctness and effectiveness of the modeling of WSN data fusion survivability analysis based on SPN. This model can provide the theoretical basis and guide for designing a survivable WSN.

mi-rigid base on crack resistance, using orthogonal experimental design method, arranged 16 groups of orthogonal test and conducted the water content test and drying shrinkage test that aimed at various ages from 5d to 50d respectively. The results indicated that with the increasing of waste asphalt content, the shrinkage gradually increasing and the maximum reached when the dosage of waste asphalt concrete was 55%, since then, with the increasing of waste asphalt content, the shrinkage gradually decreasing and the range was largely. Fiber has little effect on moisture loss and shrinkage, with the increasing of fiber content, the moisture loss of materials with different ages increased gradually and the maximum loss rate reached when the dosage of fiber was 4, then the moisture loss decreased gradually after that. As for shrinkage, it reached minimum value when the dosage of fiber was 2.5. Mixing waste asphalt concrete and fiber in reasonable dosage can improve the crack resistance of materials.

Objectives The aim of this study was to compare 3D accuracy of tooth image reconstruction from three kinds of CT scans using 3D superimpositional method. Methods 18 sound extracted human teeth were scanned by 3D optical system, spiral CT, micro-CT, and cone-beam CT scanner. The digital teeth images reconstructed from three kinds of CT scans were superimposed onto the standard image from optical scans respectively. Distribution patterns of shape discrepancy were presented using histogram, as well as showed in different colors on the superimposed imagines. The ratio of voluminal discrepancy versus the volume of the standard image (RVD/VS) was calculated and analyzed, using the matched-pair t-test and rank sum test. Results Compared with the standard tooth image, the average RVD/VS of digital teeth images by the micro-CT, cone-beam CT, spiral CT scans were 5.11%, 20.73%, 24.60% respectively, and there were statistically significant difference among the three kinds of CT scans (P

A secure and stable equipment management system is very important to an enterprise, the use of advanced technology in equipment management system, now the popular application of advanced distributed database operation mode, make the equipment management information system has strong practicability and high reliability. The equipment management work requirements, procurement plan, use, repair, and scrap the whole process of information recording, tracking, monitoring, both capital plan, which is the organic combination of physical and financial, and provides users with detailed and accurate information and convenient management means.

This paper proposes a kind of on-line control system for operation mode in substations, which can read data on-line from EMS, and then calculate total loss of substations in parallel operation, split operation or individual operation mode. According to the result, the system can select the most optimized way and feed the conclusion back to EMS, which can make substations operate in the most optimized way. The system is suitable for optimization of substation in rural power grid.

Simple joint is a common connection in tubular structures. Local buckling occurs in panel zone when the joints bear heavy loads, and local buckling will reduce the bearing capacity and stiffness. In order to improve the bearing capacity of tubular joints, the joints need to be strengthened. In this paper, the bending performance of the joints will be enhanced by welding a tile shaped plate outside the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different tile shaped plate was analyzed. The results showed that the bearing capacity of the joints experience obvious change with variation of thickness, whereas the bearing capacity has no change with variation of radian.

the control strategy has a direct impact on the performance of active power filter. Creating system model in the simulation software to research and analyze. Results show that the hysteresis comparison control method can track the harmonic current accurately, and control inverter circuit generate compensation current quickly and accurately. And doing spectrum analysis for the power grid currents before, the spectrum figures show that the power grid current harmonics has been suppressed greatly, and the compensation effect is very significant.