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Background: We aimed to determine whether there is an association, in young adults, between the occurrence of lumbar disk herniation（LDH）at a given segment and the segment’s facet joint parameters [facet orientation (FO) and tropism (FT)]. In addition, associations between facet joint parameters in the corresponding segment and LDH laterality were also investigated.Methods: We retrospectively analyzed data from 529 patients who were between 18 and 35 years old, who had experienced single-level LDH (L4–5 or L5–S1) between June 2017 and December 2019, and with less than 2 years of clinical history. We included an additional 122 patients with no history of LDH as an age-matched control group. LDH were classified by laterality (left-sided, right-sided, or central herniation). At each level (L4–L5 or L5–S1 segments), we investigated the relationship between facet joint parameters and herniation laterality. Results: FOA values at the L4–L5 level and the L5–S1 level were significantly lower and FT was higher for the LDH group compared with those for the control group. The level at which LDH occurred, FOL, FOR, and FT differed significantly among the three groups. There was a significant association between herniation laterality and FO at the L4–L5 level but not at the L5–S1 level.Conclusions: Abnormal facet joint parameters are significantly associated with LDH. Young adults with higher FT should be paid more attention, to prevent the occurrence of LDH. At the L4–L5 level, intervertebral disk herniation tended to occur ipsilateral to the side with a lower facet joint angle when FT was present.

As a defense technology with endogenous security, mimic defense plays an important role in network security research. The scheduling of executors is one of the severe problems to take into account for mimic defense, and current research lacks comprehensive consideration of the influence of system architecture and attack behavior on scheduling algorithm. Based on previous research, this paper first introduces concept of heterogeneity and confidence according to vulnerability attributes and attack distribution characteristics to characterize the executors. Moreover, the TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) algorithm is brought in to optimize the system security and improve operating efficiency. Experimental results showed that,compared with the existing algorithms, Random, MD, RSMS, it improves the security of the system in non-uniform distributed attack scenario and the operating efficiency in each attack scenario.

With the expanding of the scale of power grids, the uncertainty and complexity of power system operation are increasing. Critical clearing time (CCT) is the key to transient stability assessment (TSA) in power system operation, security defense, maintenance and other scenarios. The application of machine learning to TSA has become a research hotspot. In this paper, a method of obtaining the CCT by machine learning is proposed. First, time domain simulation under electrical fault is utilized to obtain samples for machine learning. Second, pattern features of transient stability are obtained from the samples, the maximum information coefficient method is used to reduce feature dimension, and the Box-Cox transformation is used to improve data distribution characteristics. Further, based on the XGBoost, Random Forest algorithms, a stacking model with SVR as the meta learner is established to improve the performance of CCT prediction. In the end, this proposed method is verified via the CEPRI 8-machine 36-bus system. The results prove that this method can provide accurate CCT predictions, and it is also robust to load changes.

Intervertebral disc degeneration (IDD) is a globally occurring disease that represents a significant cause of socioeconomic problems. Currently, the main method for treating IDD is surgery, including discectomy and vertebral fusion. Several in vitro experiments demonstrated that platelet-rich plasma (PRP) could stimulate cell proliferation and extracellular matrix regeneration. Additionally, in vivo experiments have proven that PRP injection could restore intervertebral disc height. Clinical studies demonstrated that PRP injection could significantly relieve patient pain. However, further studies are still required to clarify the roles of PRP in IDD prevention and treatment. This review is aimed at summarizing and critically analyzing the current evidence regarding IDD treatment with PRP.

With the large-scale development utilization of wind resources and the continuous expansion of the scale of the power grid, the uncertainty of the power grid source and load has increased the instability of the power grid. This paper studies the mathematical characterization method of the source and load uncertainties of renewable power grid, and uses the prediction box theory to dynamically characterize the source and load randomness and volatility. A source scenario generation method based on Copula function and geographic correlation and load scenario generation method based on similar daily measurement are proposed. Test examples are performed to verify the accuracy of the proposed methods. Based on electrical betweenness, a rapid reduction method of the system operating scenario is proposed. The methods that we describe here can provide a large number of operation scenarios consistent with the actual operation of the system and avoid massive power flow calculation, so as to facilitate the analysis of risks brought by uncertainty to the operation of power system.

Background With respect to spinal surgeries, elucidating absolute and relative amount of hidden blood loss (HBL) is of great importance in order to avoid aforementioned potential complications. To evaluate HBL and its possible risk factors among patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar degenerative diseases. Methods Between June 2018 and March 2019, 137 consecutive patients with lumbar degenerative disease, who underwent operation with MIS-TLIF technique, were enrolled in this study. The patient’s demographic characteristics and blood loss-related parameters were collected, respectively. The Pearson or Spearman correlation analysis was used to investigate an association between patient’s characteristics and HBL. Multivariate linear regression analysis was used to confirm independent risk factors of HBL. Results A total of 137 patients (86 males and 51 females, age range 19–78 years) were reviewed in our hospital. A substantial amount of HBL (488.4 ± 294.0 ml, 52.5% of TBL) occurred after MIS-TLIF. Multivariate linear regression showed that the age, muscle thickness, the Patients’ Society of Anesthesiologists (ASA) classification, patient’s blood volume (PBV), total blood loss (TBL), postoperative (i.e., day 2 or 3) hematocrit (Hct), Hct loss, and fibrinogen level were independent risk factors for HBL (P1 = 0.000, P2 = 0.002, P3 = 0.006, P4 = 0.002, P5 = 0.003, P6 = 0.048, P7 = 0.004, P8 = 0.000). Conclusion A large amount of HBL was incurred in patients undergoing MIS-TLIF. More importantly, the age, muscle thickness, ASA classification, PBV, TBL, postoperative Hct, Hct loss, and fibrinogen level were independent risk factors for HBL in MIS-TLIF. HBL and its risk factors should be paid more attention to during the perioperative period.

BACKGROUND CONTEXT Facet joints have been discussed as influential factors in the development of lumbar degeneration, which includes disc herniation and degenerative lumbar spondylolisthesis. Facet orientation (FO) and facet tropism (FT) are two important structural parameters of the lumbar facet joints. Many previous studies have focused on single parameter analysis of the lumbar spine. Owing to the correlation between independent variables, single-factor analysis cannot reflect the interaction between variables; however, there has been no corresponding biomechanical method developed to address this problem. PURPOSE To investigate the complex biomechanical influences on the lumbar spine when vertebral FO and FT are varied using finite element analysis (FEA) and contour maps visualization, and analyze the biomechanical role of facet joint structural parameters in the process of lumbar degenerative diseases. STUDY DESIGN A biomechanical modelling, analysis, and verification study was performed. METHODS : A three-dimensional non-linear FEA model of 3 denucleated intervertebral discs (L2-3, L3-4, L4-5) with adjacent vertebral bodies (L2-L5) was created. Previously performed in vitro experiments provided experimental data for the range of motion in each load direction that was used for calibration. For 12 lumbar models, different facet joint angles relative to the sagittal plane at both L3-4 facet joints were simulated for 35°≤FO≤50° and 0°≤FT≤15°. By modifying different values of FO and FT, FEA simulation of different lumbar spine models was performed. Contour maps were used to visualize the FO- and FT-relevant data. RESULTS Under flexion, extension, and torsion moments, facet joint contact force and intradiscal stress increased with increasing FT. In the condition where FT remained 0° and increasing FO values, facet joint contact force and intradiscal stress remained low with no apparent increasing or decreasing trend when the model was under flexion, extension, and torsion moments. In the condition where FO and the FT values were varied at the same time, the highest force and stress regions in the contour maps were observed when all three types of moments were applied. Stress distributions of the L3-4 disc with different FT and FO values showed disc stress increased significantly with increases of FT and was concentrated on the ipsilateral region of the facet joint with the more sagittal orientation. CONCLUSIONS The combination of FO and FT has an important impact on the corresponding disc and facet joints, but FT played a more significant role. Moreover, disc stress was concentrated on the ipsilateral region of facet joint with greater sagittal orientation when FT existed. FT with high sagittal orientation may increase risk of recurrent LDH due to increase ipsilateral disc pressure. CLINICAL SIGNIFICANCE These biomechanical findings may help clinicians to understand the prognosis of some lumbar degenerative conditions.

Long noncoding RNA SPRY4‐IT1 has been reported to promote melanoma cell growth and invasion, and to block apoptosis. The purpose of this study was to investigate the clinical significance of SPRY4‐IT1 in patients with malignant melanoma. The relative expression levels of SPRY4‐IT1 were measured in plasma samples from 70 patients and 79 healthy controls by quantitative reverse transcriptase polymerase chain reaction. SPRY4‐IT1 expression is high in melanoma patients but low in healthy controls, and is closely associated with tumor site and tumor stage. Elevated SPRY4‐IT1 significantly reduces overall survival rates of patients and is considered as an independent prognostic factor in patients with melanoma. The prognostic nomogram shows a good prediction of the probability of 5‐year overall survival of patients with melanoma (c‐index: 0.72). The calibration curve for the probability of survival presents good agreement between actual outcomes and predictive consequences. In summary, SPRY4‐IT1 may be a potential prognostic marker and a potential therapeutic target.

Ocean environmental corrosion and mechanical load vibration introduce considerable negative effects caused by the fluid-structure-environment interaction. A new design scheme for a blade with salinity corrosion resistance and mechanical fatigue resistance is proposed, based on numerical simulation and fatigue tests. The one-way fluid-structure interaction (FSI) model for an ocean current turbine blade was established and calculated by a computational fluid dynamics (CFD) solver and finite element method (FEM) solver. According to the FSI results, the maximum equivalent stress and deformation in extreme operating conditions are found to be within material and structural limits. On this basis, an aluminum alloy/nano particles reinforced polypropylene multilayer composite blade was designed and fatigue tested. The results show that an obvious crack-resistance effect exists within a certain stress range, and there is basically no change in the fatigue crack growth rates of NPRP in the four environmental fatigue tests. The multilayer composite blades with immersion pretreatment can stand 1 × 107 cycles of fatigue tensile loads and torque loads without failure. The results provide specific theoretical guidance for the optimization of the structural design of ocean current turbine blade in ocean environment.

With the continuous development and popularization of network equipment and services, people's dependence on cyberspace is becoming stronger and stronger, and the importance of network security is becoming more and more prominent. Mimic defense is based on the system architecture of dynamic heterogeneous redundancy. Data is sent to multiple heterogeneous functional equivalents through the input agents, and then the response of heterogeneous functional equivalents is judged according to a certain arbitration policy by the output agent. The abnormal output of a functional equivalent can be effectively eliminated, enabling the system to achieve intrusion prevention against unknown system vulnerabilities or backdoors. This paper analyzes the effect of the isomorphism of functional equivalents on system security, and proposes a mimic method based on the equivalence of mimicry maximization. Experiments have shown that the effectiveness of security defense can be significantly improved.

Micro-electromechenical Systems (MEMS) gyroscope is widely used in many occasions to measure the angular speed of the moving objects and attracts the attentions of many research institutions all over the world. This kind of sensor possesses the advantages of high degree of integration, low cost and consumption of power. This paper first introduces the research development of silicon MEMS gyroscope since eighties of last century; the researches of many institutions such as Draper Laboratory and UC Berkeley are mentioned and different design principles, control methods and structures are presented. This review then presents the key theories and technologies of the sensor and some research results of them. In additional, some recent new applications of MEMS gyroscope are also been introduced in this paper such as wearable motion capture system and micro inertial measurement unit. Finally, according to the review, some views of silicon MEMS gyroscope and its future prospects are put forwarded.

In the present study, the expression of p53, mouse double minute 2 homolog (MDM2), eukaryotic translation initiation factor 4E (eIF4E), and epidermal growth factor receptor (EGFR) were investigated in nasopharyngeal carcinoma (NPC), and the correlation between their expression and clinicopathological characteristics and prognosis was analyzed. The medical records of 96 NPC patients who had undergone biopsy prior to radical radiotherapy and chemotherapy between 2005 and 2009 were reviewed, retrospectively. All patients received intensity-modulated radiotherapy with concurrent platinum-based chemotherapy. Patients were followed-up for three years. Streptavidin-peroxidase immunohistochemistry was used to evaluate the expression of p53, MDM2, eIF4E and EGFR in NPC biopsy specimens, and the association between their expression and clinical parameters and survival was analyzed. The p53, MDM2, eIF4E and EGFR expression rates were 65.6% (63/96), 79.16% (76/96), 77.08% (74/96) and 89.5% (86/96), respectively. p53 (χ2,20.322; P=0.001) and EGFR (χ2,8.337; P=0.005) expression were found to correlate with T stage, whereas MDM2 (χ2,16.361; P=0.001) expression was found to correlate with lymph node metastasis. p53 expression was found to inversely correlate with MDM2 expression (r, −3.24; P

The experimental advanced superconducting tokamak (EAST) is a superconducting tokamak, which successfully achieved the first plasma discharge in 2006. The major radius of EAST plasma is 1.9 m, and its central magnet field is 3.5 T. In the past few years, EAST has made many achievements, such as 60-s double-null divertor configuration plasma and 1-MA plasma. In 2012, 411-s long-pulse discharge with 0.28-MA plasma current and 32-s H-mode operation was achieved at the seventh campaign. In addition, various means for mitigating ELMs have also been demonstrated to facilitate long-pulse operation. The experimental results and engineering experience obtained from EAST can be used as a reference for fusion next step. To make further progress, much optimization work should be done in next step. Based on the present EAST heating system, two sets of 4-MW neutral beam injection, one set of electron cyclotron resonance heating, and lower hybrid current drive will be installed to achieve more than 30-MW total heating power. The upper divertor will be updated to W-Cu divertor, which consists of monoblock structure and tungsten armor that can withstand 10- MW·m-2 heat load. To increase the upper divertor's ash removal efficiency, one new cryopump will be added on the behind of it. Aiming to improve plasma configuration and enhance its stabilization, the EAST resonant magnetic perturbation (RMP) coils will be designed, fabricated, and installed. The RMP coils will integrate the functions of error field correction, edge localized mode, and resistive wall mode. About 45 kinds of diagnostics will be used in the next campaign and all of them will be integrated on six ports as port plug. In addition, some fusion technologies are also considered in EAST to validate for ITER and future reactor.

Emergy analysis,which both considers the economic aspect and the natural contribution through meaningful comparison across different systems,has been proved to be a powerful tool to assess the ecological economic systems and processes,especially in the mariculture field.In this paper,emergy analysis method is used for establishing a related index system to analyze the large yellow croaker system in Dongji.System indices such as TR,EPD,ELR,EYR,PEEI,EERY,ESI and EISD were applied to characterize the resource use,environmental impact and the overall sustainability of the studied system.And the data obtained through the comparison of large yellow croaker aquaculture system in Dongji island and three aquaculture systems surrounding the Pearl River Estuary was discussed.The results showed that the TR of large yellow croaker aquaculture system is 1.46×106sej/J,which was in the middle of three aquaculture systems surrounding the Pearl River Estuary,but lower than the average value of systems studied before.The EPD of large yellow croaker aquaculture system is 2.07×1017sej · hm-2 · a-1,and ELR is 91.10.And in this study,purchased external resource emergy inputs achieved a greater effect than putting renewable environmental resource emergy in large yellow croaker aquaculture system.And results showed the system had more dependence on purchasing external resource emergy inputs.The ESI is 0.011,EISD is 0.02,which indicate that the large yellow croaker aquaculture system is less sustainable.Based on sensitivity analysis,ESI and EISD these two sustainable indicators are elevated,due to half reduced the inputs amount of fingerlings and double increased the inputs of rain chemical.Based on above analysis,getting two effective solutions:(1) By reducing feed inputs,improving the feed utilization efficiency,aquaculture facilities deployed in areas with more rainfall,to improve local renewable resources inputs proportion;(2) By improving the labor efficiency or breeding technology from depending relying on labor to relying on technology,to reduce the purchased external resources inputs.

In order to collect scientific data of lunar-based extreme ultraviolet camera,generate images,and display these images in real-time,a display system of lunar-based extreme ultraviolet camera is designed.This system adopts FPGA of XILINX Virtex II series as the image acquisition,processing and control core.It has the functions of receiving scientific data,generating and storing the image data,as well as controlling USB interface.The system can communicate with extreme ultraviolet camera based on RS-422 interface,and receive scientific data by LVDS interface.The image data is transmitted to computer through USB bus.And the computer can generate images and display these images in real-time.Imaging experiment,using this system and the extreme ultraviolet camera,has been done.The result of this experiment shows that the system can correctly collect scientific data,generate image data and display image when the photon counting rate is 66 kcps.

Nuclear fusion is one of the most important ways to resolve human energy issues. The main structure of nuclear fusion device and its functions are introduced in this article. Virtual simulation technology has been used in the process of the conceptual design, detailed design and optimization of the fusion device structure. Electromagnetic analysis of the ITER feeder system show the specific application of virtual simulation technology in nuclear fusion engineering, as well as the thermal analysis of ITER thermal shield. It verifies the importance of virtual simulation technology.

International thermonuclear experimental reactor (ITER) soft x-ray (SXR) diagnostic camera is an indispensible component used to measure signal intensity of SXR, which can reflect the internal properties of plasma. In this paper, the preliminary structural design and working principle of SXR camera is demonstrated, to investigate its seismic performance, modal analysis has been performed to obtain natural frequencies, effective mass and mode of vibration in first ten modes by means of ANSYS software. Then according to two parallel seismic analysis methods used in ITER, the calculations have been performed and the corresponding results have been illustrated respectively, the stress intensity and displacement are all within the allowable margin, which indicates that the design is reasonable and feasible. It will also provide beneficial reference for subsequent work.

Based on the requirements of shotwave infrared imaging spectrometer with wide field of view,considering the restrictive off-the-shelf detectors,a split field of view(FOV) method was developed.The principle of split field of view was analyzed.A spaceborne shortwave infrared imaging spectrometer with wide field of view was designed using the method.The imaging spectrometer are composed of a 11.42° telecentric off-axis three-mirror anastigmatic telescope and two offner convex grating spectral imaging system.Ray tracing,optimization and analyzing were performed by CODE V and ZEMAX software.The analyzed results demonstrate that the modulation transfer function for different spectral band is more than 0.7 which satisfies the pre-designed requirement.

Pairwise combinatorial coverage testing which is a significant method for test data generation in functional test fields was discussed.As the method is difficult of solution,a improved method of test data generation for the solution space tree based on intelligent planning was proposed according to the relationship of different factors in the system.The method generates all the available data into a solution space tree,then searches a path from a root node to a leaf node to produce a test data. Experimental results show that this method can test adequately and cover more effect factors of software system by using less test data and can achieve the combinatorial corerage of two factors for test data.As compared with traditional methods,it can obtain the simplest and more complete data sets.In conclusion,it improves the efficiency and veracity of generating test data when this method is taken to a bear space camera software test.

Robust entanglement created between an optical cavity field mode and a macroscopic vibrating mirror with an optical parametric amplifier is shown. Increasing the gain of the optical parametric amplifier makes the line of the logarithmic negativity E N move to the range of the larger detuning and higher temperature. Such optomechanical entanglement can be generated even at room temperature with current experimental parameters. Compared with other proposals, we have considered the one-to-one correspondence between the detuning and the input power, which is reasonable with the fact that the mean shift of the cavity frequency is determined by the radiation pressure which is related to the input power. Such consideration may be valuable to current experiments.

High-power, high-efficiency 808 nm laser diode arrays for pumping solid-state lasers have been widely used in industrial, scientific, medical and biological applications. The tendency of development of 808 nm laser diode pumping with high power, high efficiency and long lifetime is well-known. Diode-pumped solid-state system with high-efficiency laser diode array has many advantages such as compact volume, lower weight and energy saving. Currently, commercial 808 nm diode laser arrays with lower power conversion efficiency of about 50%-55%, due to the optical absorption losses for GaAs-based epitaxial materials, have been reported. In order to reduce series resistance and thermal resistance, heavily doped p-type waveguide and cladding layers are employed. However, the absorption loss on the free carriers in heavily doped p-type layers is dominant, leading to a lower power conversion efficiency. In order to achieve a high efficiency, the following requirements must be considered: improving the internal quantum efficiency by reducing the carrier leakage and increasing the electron injection efficiency; minimizing the voltage drop by optimizing the operating voltage; reducing the series resistance and thermal resistance of device; minimizing the internal loss including free-carrier absorption loss and scattering loss by designing optimized waveguide and cladding structure. In this paper, optimizing the epitaxial structure and fabricating technologies are demonstrated to achieve the high efficiency and high power. The asymmetric broad waveguide epitaxial structure with lower absorption loss in p-type waveguide and cladding layer is designed in order to achieve the above goals. The high-efficiency epitaxial structure is optimized including the thickness, doping and composition for each layer structure. The strained quantum well diode laser with lower transparency current and higher differential is of benefit to achieving the high power. A novel asymmetric broad waveguide structure is designed by optimizing the waveguide thickness and component of p-waveguide so as to reduce carrier absorption loss, the optical absorption loss in this epitaxial structure is achieved to be as low as 0.63 cm-1. The wafer is grown by metalorganic chemical vapor deposition on an n-GaAs substrate. The optimized growth conditions and substrates orientation are extensively studied to improve the crystal quality and reduce the internal loss and defects. The wafer is processed using standard procedures. For the fabricated 1-cm laser diode array mounted on P-side down on copper microchannel cooled heatsink, the device shows an output power of 150 W under an operating current of 135 A with an emitting wavelength of 809 nm, an operating voltage of 1.76 V, a slope efficiency of as high as 1.25 W/A, and maximum power conversion efficiency of as high as 65.5%, which is the highest level of 808 nm diode laser array with an output power of 150 W.

MIMO-relay technology is accepted as a promising solution to improve cell edge performance for the future 4G wireless system. In this paper, a relay filtering and signaling method along with different routing schemes are proposed to improve the average capacity of the network from multiple sources to multiple destinations aided by multiple relays, where each node is equipped with multiple antennas. In the paper, a relay filtering method is first studied to decompose the complex channel of ‘multiple sources’-‘multiple relays’-‘multiple destinations’ into several independent channels of ‘single source’-‘single relay’-‘single destination’; then the relay signaling method is discussed to optimize the capacity of each decomposed channel, and the relay power allocation scheme among different decomposed channels is further analyzed; at last different routing schemes are compared in the relay network, and an optimal routing scheme with large signaling overhead and several suboptimal routing schemes with less signaling overhead are proposed. Numerical results show that the proposed relay signaling and routing schemes can effectively take advantage of the MIMO-relay network and improve network capacity.

his report are given of two experimental progresses from vacuum micro-electronics (YlkfE) field of interest. One aspect of interest is a simple method to monitor the type or nature of a diamond thin jlm resultants from the microwave plasma chemical vapour deposition (MPCVD). A very stable Raman microprobe which was in cooperation with the micro-sampling techniques plus a standard diamond sample have been used to evaluate rapidly the Jilm resultants. Combining above method with the SEA4 morphology observation, a simple and rapid monitor method to offer the nature of a film is formed without using several surface analysis equipments . Another aspect of interest is, for thejrst time in our ME area, we observed successfully a very small thin Jilm which have only about 2 micrometers diameter and was grown on the top of a trp of a silicon Jield emission array (Si-FEA). The research result and analysis in detail will be given.

Objective To elucidate whether plasma soluble receptor for advanced glycation end products (sRAGE) is the biochemical markers indicating coronary artery disease and coronary artery disease with acute myocardial infarction (AMI). Method Plasma levels of sRAGE was determined by enzyme linked immunoabsorbent assay in patients who came from Cardiology Department of Tiantan Hospital form March to May 2009 categorised as group I (non-CAD subjects), group II (CAD without myocardial infarction subjects), and group III (CAD with AMI subjects). Results Plasma levels of sRAGE was higher in group III than in group II (p 0.05). Further more, to evaluate whether sRAGE is the biochemical markers indicating the AMI in CAD patients, ROC curve was used, and area under the curve was 0.855(p=0.000). Conclusion sRAGE may be new biochemical markers indicating AMI in the patients with coronary artery disease. The diagnostic sensitivity of sRAGE is 75% and specificity is 86.4%.