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The ubiquitin ⁃ proteasome system (UPS) and autophagy system are two systems in eukaryotic protein quality control, both of which can play a biological role independently and also closely related, and play a key role in clearing abnormal proteins and secondary injury mechanism of nerve cells after traumatic brain injury (TBI). This article reviews the mechanism and interaction of UPS and autophagy system in secondary injury after TBI, in order to provide theoretical basis for protecting nerve function and improving prognosis after TBI.

China is rich in marine resources, and with the development of its economy and the improvement of its transportation level, the use of immersed tunnel technology is increasingly more extensive. The Shenzhen–Zhongshan Bridge is the first steel shell immersed tunnel in China. The immersed tunnel is located in a sea mud area that is not easy to inspect and maintain, and its steel shell structure is eroded by seawater, which shortens its service cycle, and severe corrosion affects its safe operation. Its durability requirement is 100 years. For the service environment and ultrahigh durability requirements of the Shenzhen–Zhongshan Bridge steel shell concrete immersed pipe and many other characteristics, at present, few engineering and research references at home and abroad can be used. Thus, the corrosion development law of the outer wall of an immersed steel shell in a marine environment must be studied and revealed. In this work, dissolved oxygen (15.2 mg·L–1) was artificially added to a simulated seawater solution as a depolarizing agent to realize the acceleration process of a corrosion simulation acceleration test in the laboratory. The test set cycle was 1, 7, 15, 30, 90, 180, and 365 d, and the test temperature was 25 ℃. Through the electrochemical impedance spectroscopy (EIS), the Tafel polarization curve, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), confocal laser scanning microscopy (CLSM), and other analytical and testing methods of samples with different test cycles, the corrosion occurrence and development law of Q390C low-alloy high-strength structural steel used in deep–medium channel immersed tunnel steel shells under simulated seawater conditions was studied. The corrosion products of Q390C steel in seawater are mainly found to be Fe3O4, α-FeOOH, γ-FeOOH, and a small amount of CaCO3, and their uniform corrosion and local corrosion rates decrease exponentially and eventually tend to stabilize. CLSM test shows that the surface of the specimen begins to corrode uniformly after a test cycle of 15 d, and the pitting corrosion pit depth of the specimen with a test cycle of 365 d can reach 99 μm. The long-term accelerated corrosion test of the steel shell of an immersed tunnel in seawater in this paper is of great importance to ensure the long-life durability of immersed tunnels in marine engineering and similar construction projects.

In order to explore the effect of Chuzhou chrysanthemum powder application in bread processing on dough characteristics and bread flavor and antioxidant activity, the thermal and mechanical properties of dough with added Chuzhou chrysanthemum powder were measured using Mixolab 2, and the volatile flavor compounds in the resulting bread were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS). In addition, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) cation radical scavenging capacity and the total flavonoid content of the bread were determined. The results showed that the water absorption rate of dough significantly increased while the peak viscosity and setback of starch decreased upon addition of Chuzhou chrysanthemum powder. Compared with the control bread, the content of flavor components in Chuzhou chrysanthemum incorporated bread was higher, and d-camphor was found to be the characteristic flavor component of Chuzhou chrysanthemum. The volatile flavor components in the samples with and without Chuzhou chrysanthemum were obviously different according to principal component analysis (PCA). The total flavonoid content of Chuzhou chrysanthemum incorporated bread was 260.47 mg/100 g, which was significantly higher than that of the control bread, and the DPPH and ABTS cation radical scavenging activities were higher than those of the control bread. In conclusion, addition of Chuzhou chrysanthemum powder to bread can enrich the flavor components and improve the antioxidant activity of bread, which provides a reference for the application of Chuzhou chrysanthemum in bakery foods.

Hydrogen peroxide and activated carbon were separately used for decolorization of Thesium chinense Turcz polysaccharides. The physical characteristics of the two decolorized samples were analyzed by X-ray diffractometry (XRD), thermogravimetry, laser particle size analyzer and rheometer, and their inhibitory activities against the proliferation of liver cancer cells were compared, as well as their effects on the gelation temperature of κ-carrageenan. The results showed that the crystalline structure of the activated carbon-treated sample was more obvious in the XRD pattern. Its apparent viscosity was higher than that of the hydrogen peroxide-treated sample at the same concentration. The thermogravimetric curve showed that the thermal decomposition degree of the hydrogen peroxide-treated sample was higher than that of the activated carbon-treated sample (mass loss percentage of 59.33% and 53.21%, respectively). At concentrations of 6–10 mg/mL, the activated carbon-treated sample showed inhibitory activity against the proliferation of HepG2 cells, while the hydrogen peroxide-treated samples did not have any inhibitory effect in the concentration range of 1–10 mg/mL. Furthermore, the increase in temperature hysteresis of blends of the activated carbon-treated-treated polysaccharides with κ-carrageenan was greater than that in blends of the HTP-treated polysaccharides with κ-carrageenan. Therefore, different decolorization methods can affect the structure and application characteristics of Thesium chinense Turcz. polysaccharides.

The formation of Am(Ⅲ) colloid and its adsorption behaviors on bentonite colloid were investigated in Beishan 03 groundwater. A series of influencing factors, such as, pH, CO2 concentration in gas atmosphere, ionic strength and temperature, on colloidal stability and adsorption behavior were explored using Zeta potential laser particle size analyzer, asymmetric flow field flow fractionation system(AF4) and batch experimental method. The results show that the formation and stability of Am(Ⅲ) are closely dependent on the chemical natures of aqueous solution. Increasing temperature or increasing ionic strength will reduce the stability of Am(Ⅲ) colloids, while the increase of carbon dioxide concentration and pH will be beneficial to the stability of Am(Ⅲ) colloid. In addition, with the increase of pH, the density of Am(Ⅲ)-bentonite colloid particles increases, while the Am(Ⅲ) adsorption rate first decreases and then increases; the increase of ionic strength is favor of Am(Ⅲ) adsorption, but the density of colloidal particles decreases; the increase of CO2 concentration in gas phase has a promoting effect on particle density and Am(Ⅲ) adsorption.

Aiming at the problems of slow update frequency of channel key, low generation rate and limited node resources in the IoT scenario, a DMA-based physical layer key generation method was proposed, by using the agility and reconfigurability of DMA to improve the time variability and randomness of received signal.Firstly, DMA was used by the transmitter to randomly weight the signal and send it to the receiver, which could enhance the randomness of signals on the premise of ensuring the transparent reception of the signal.Then, the key from the received signal was extracted by the sender and receiver.By combining the rapid changeability and randomness of DMA, the randomness of signal source and the randomness of natural channel, a composite channel was constructed to improve the randomness of the key source.In addition, the channel estimation was transfered overhead from the terminal to the base station, which effectively reduced the overhead and delay of the communication system, and was suitable for IoT scenarios with asymmetric resources and lightweight equipment.Simulation results show that the proposed method can effectively improve the key generation rate in quasi-static scenarios, and the generated physical layer key has passed the NIST test.

Objective: This study aimed to research and develop puffed blueberry dregs indica rice and fruit snack food. Methods: Using indica rice flour and blueberry residue powder as raw materials, three experimental factors including moisture content, extrusion temperature and screw speed were selected, and the expansion degree, anthocyanin content and sensory score were taken as comprehensive indexes. The expansion process was optimized by single factor and orthogonal test, and the antioxidant activity of the expanded products was studied. Results: The optimum process parameters were as follows: the moisture content of the material was 16%, the temperature of the four extrusion zones were 50—80—110—130 ℃ and the screw speed was 160 r/min. The indica rice fruit with blueberry residue obtained under this process has the highest comprehensive score of 62.30±0.51. The results of antioxidant test in vitro showed that compared with puffed indica rice fruit, the scavenging rates of DPPH and ABTS by blueberry residue indica rice fruit increased by 60.19% and 73.67% respectively. Conclusion: the optimal processing parameters of indica rice fruit with blueberry residue were obtained, and the product also showed good antioxidant properties.

In order to satisfy the requirements of the transmission rate and spectrum resource for various terminals and equipment in the satellite internet, a generalized approximation-based message passing optimization satellite receiver was designed.Considering the multi-user detection in the satellite network using the non-orthogonal multiple access, a factor graph was established based on the graph model, and the factor graph was used to analyze the message passing model of the system and a message passing algorithm was proposed.Based on the generalized approximate message passing method, the complexity of the traditional multi-user detector based on message passing was further reduced.Under satellite channel condition, generalized approximate messaging satellite receivers were studied.The simulation results show that the proposed algorithm can effectively solve the signal coexistence problem of multi-users, and reduce the computational complexity of the algorithm.

With the characteristics of all-terrain, all-weather and seamless coverage, satellite communications have become a potentially important part of 6G.An important prerequisite for achieving satellite intelligence is that the satellite have on-board processing capabilities.Multi-user detection (MUD) is a classic method of suppressing multiple access interference (MAI) in wireless communication, such as MMSE, Gaussian processregression (GPR) and other algorithms.Due to the inverse matrix required in the detection process, the algorithm complexity is usually cubic, and it is diff cult to directly apply to satellite platforms because of its limited processing capabilities.The conditional neural process combined the characteristics of the low complexity of the neural network and the data-eff cient of the Gaussian process.The neural network was used to parameterized the Gaussian process to avoided the inversion of the matrix, thereby reduced the computational complexity.The application of conditional neural process in MUD was studied.The simulation results showed that, while reduced complexity, conditional neural process also greatly improved the performance of bit error rate (BER).

Reinforcement corrosion, due to the presence of chloride ions, is a major cause of the degradation of reinforced concrete structures. Nowadays, electrochemical rehabilitation (ER) is becoming a common technique for repairing reinforced structures. Due to the transmission properties of the micro-pores in concrete, chloride ions can be transferred to the outside of the concrete through the pores under the driven force of electric field. Compared with other conventional technologies, ER presents many advantages, such as high efficiency and little influence on the environment and surroundings. However, previous studies indicate that ER exhibits negative effect on the interfacial bonding properties of steel concrete. As the main influence factor for ER, varying current densities may consequently change the bond loss between steel and concrete. In addition, large current density significantly reduces interfacial bond. However, current studies lack relevant quantitative research results and fail to propose an effective method to solve the problem after electrochemical repair since aiming at electrochemical rehabilitation will most likely result in the bond deterioration of reinforced concrete. In this study, the bond-slip curves were obtained through central pull-out specimens after ER with various electrochemical parameters, and the relationship between the electrochemical parameters (current density and conduction time) and the bond behaviors were investigated. Finally, a degradation model of bond strength considering the influences of the two parameters mentioned was established. Results show that the bond strength decreases significantly with high current density and long conduction time. Using a current density of 5 A·m–2, reduction of the max bond force increased up to 22.6% and 56.9% under a conduction time of 15 and 28 d, respectively. The proposed model can be used to quantitatively characterize the reduction of bond strength after electrochemical rehabilitation. Good consistency of results was observed after comparing the evaluated results with that of the experiment.

Objective: This study aimend to explore the appropriate transformation path of regulatory power for food safety "social co-governance". Methods: The state of "social co-governance" mode of food safety was analyzed and the possible secondary risks of "decentralization" of regulatory authority were analyzed, so as to explain the rational transformation of regulatory authority. Results: The blind decentralization of regulatory power will cause the policy risks of governance loss and disorder, leading to greater food safety accidents. Conclusion: It is necessary to make clear the transformation of "strict supervision to refinement and flexibility", adhere to the transformation of "basic rights of social co-governance" and "actively cultivate and stimulate the governance rationality of multiple subjects".

In order to establish covert wireless communication in Rayleigh fading environment with noise uncertainty,a scheme of downlink covert wireless communication based on complex Gaussian random coding and beam forming was adopted,and more importantly,the performance of covert wireless communication was analysed.Firstly,the covert probability of communication was analyzed by using the hypothesis test theory.Secondly,the optimal detection threshold of the illegal detection party was given and proved,and the closed expressions of the average covert probability,connection interruption probability and covert throughput of the system were further obtained.Finally,by jointly designing the transmission power and target covert rate,the optimal goal of the maximum covert throughput of the system was achieved,and the corresponding algorithm based on step search was given.The simulation results show that the beam forming technology could provide some gain for covert wireless communication.Compared with the ideal case in which the legitimate receiver is not affected by the noise uncertainty,the covert throughput in non-ideal case is significantly reduced and almost not affected by the basic noise level of the environment.

The drying and drying rate curves of Lechang taro were studied under different hot air temperatures (50, 60, 70, 80, 90 ℃), different hot air rate (1.5, 2.0, 2.5, 3.0 m/s) and different slice thickness (2, 3, 4, 5 mm). The relationship between water ratio and drying time in the drying process was fitted by the empirical models such as : Logarithmic, Twoterm, Modified page, Henderson and Pabis, WeibullⅠ. The fitting results were judged by the coefficient of determination, residual Sum of squares and reduced Chi-square. The results showed that the moisture ratio (MR) decreasing with drying time and the water ratio changes gradually. The hot-air drying of Lechang taro was mainly in slow-down drying stage. When the hot air temperature was 70 ℃, the drying rate was the fastest and the drying time was the shortest. The drying rate was faster when the hot air rate was 2.0 m/s, which was beneficial to saving energy and reducing consumption. When the slice thickness was 3 mm, the drying rate was faster and the drying time was shorter. WeibullⅠ model could describe the hot-air drying process of taro very well. The coefficients of determination were more than 0.997 91. The residual Sums of squares were less than 0.002 88. The reduced Chi-squares were less than 1.69×10–4.

The secret key generation method based on channel characteristic provides a new way for communication security.But under the conditions of multiuser and slow fading,because of the slow channel parameter changing rate,using the secret key generation method above can result in a low secret key rate.To solve this problem,a multiuser secret key generation method based on the received signal was proposed.By distributing the random signals to different users using block diagonalization precoding,base station and user can extract the secret key from the received signal.The novel method could significantly increase the secret key rate of multiuser under the quasi-static channel and slow-fading channel,which is verified by simulations.

The achievable key rate of secret key generation method in multi-hop relaying systems was relative low in Internet of things.A cooperative secret key generation algorithm based on network coding was proposed to improve the achievable key rate.Firstly,all the nodes send training sequences in turn to estimate the channels.After that the relays employ secure network coding technique to assist the two legitimate users to obtain the correlative observations of the same wireless channel,with nothing leakage about the channel information to the eavesdropper.Finally,the two legitimate users agreed on a common secret key directly over the public channel.Theoretical and simulation results validate the performance of the proposed secret key generation algorithm,and obtain that increasing the wireless transmission paths,selecting the transmission path with less hops and larger variance channels can further improve the achievable secret key rate.

Background and objective Segmentectomy can retains more healthy lung tissue than lobectomy, but it remains controversial in oncology for early stage lung cancer. The aim of this study is to discuss the problems of video-assisted thoracic surgery (VATS) segmentectomy in early stage lung cancer, by analyzing the clinical and pathological data of 35 cases and reviewing the literature. Methods There were 35 patients who received segmentectomy by complete video-assisted thoracic surgery, from May 2013 to July 2017, in single operation group in the Third Hospital of Peking University. We analyzed the patient's clinical and pathological data, intraoperative and postoperative complications, lymph node number and metastasis its situation, and compared postoperative pathology and preoperative computed tomography (CT) imaging type. In 35 cases of segmentectomy, there were 11 males and 24 females, with an average age of 57.7 years old. The lesions located in the right upper lobe were 8 cases, in the right lower lobe were 8 cases, in the left upper lobe were 13 cases, in the left lower lobe were 6 cases. The mean maximum diameter of CT imaging was 12.7 mm, and the largest diameter of hilar and mediastinal lymph nodes was less than 10 mm. 23 of them were ground glass predominating and 12 were solid components predominating. Results All 35 cases were successfully completed VATS anatomical segmentectomy. The average operation time was 153 minutes, the amount of bleeding was 51 mL. There were 10 cases of air leakage after operation, all of which were not more than 3 days. There was contralateral atelectasis in 1 case, chylothorax in 1 case. The average length of hospitalization was 6.1 days. There was no other complications outpatient related to surgery, in 30 days after discharge. The pathological changes were as follow, 2 cases of metastatic tumor, 8 cases of benign lung disease and 25 cases of primary lung cancer. In the 25 cases of primary lung cancer, there were 14 cases of invasive lung adenocarcinoma (7 cases were groundglassopacity (GGO) predominating in CT imaging), 4 cases of micro-invasive adenocarcinoma (3 cases were GGO predominating in CT imaging), 6 cases of adenocarcinoma in situ (all were pure GGO in CT imaging), 1 case of lung squamous cell carcinoma (mainly composed of solid in CT imaging). An average of 7.2 lymph nodes were removed in 25 cases of lung cancer, and all lymph nodes had no metastasis. Conclusion VATS anatomical segmentectomy is technically safe and reliable, and the indications for lung cancer need to be strictly controlled. Its advantages still need to be confirmed by prospective randomized controlled trials.

Taking chitosan (CS) and soybean protein isolate (SPI) as composite membrane substrates and natural antioxidants as active substances, an edible active preservative film with inhibitory effect on lipid oxidation was developed. After optimizing the type and concentration of antioxidants through the mechanical properties, microstructure, physical properties, and antioxidant properties of the composite membrane, the preservation effect of the composite membrane on walnut oil was investigated. Results showed that, eight antioxidants significantly improved the oxygen-barrier ability of the composite membranes (P<0.05). Especially, the peroxide value of walnut oil was reduced by about 80% and maintained excellent mechanical properties with the addition of astaxanthin, grape seed extracts and vitamin C. When the addition of astaxanthin was 0.3%, the composite membrane exhibits the best performance, then the tensile strength, elongation at break, DPPH free radical scavenging capacity and water vapor permeability of the composite membrane were 6.546 MPa, 69.962%, 80.1%, 1.21 g⋅mm/m²⋅h⋅kPa, respectively. Scanning electron microscopy revealed that the surface of the membrane was smooth, regular and uniform. Fourier transform infrared spectroscopy showed that membrane-forming materials were extremely compatible. The differential scanning calorimeter analysis showed that the composite membrane had the highest thermal enthalpy, reaching 233.940 J/g, with the best thermal stability. When the walnut oil was coated with a composite membrane containing astaxanthin, the oil's peroxide value was reduced by 81.8%, conjugated diene by 44.4% and conjugated triene values by 66.4% compared to the control. Chitosan/soybean protein isolate composite membrane with astaxanthin significantly delayed the process of walnut oil oxidation. [ABSTRACT FROM AUTHOR]

Physical layer secret key capacity was affected by time difference of channel sounding,mobility of terminals,and additive noise.Effects on the physical layer secret key capacity were quantitatively analyzed in the uniform scattering environment.Based on the time domain statistical characteristics of narrow band wireless channel parameters with noise,a closed-form solution to physical layer secret key capacity in the time domain was derived.Afterwards,simulations in the uniform and non-uniform scattering environment were carried out to demonstrate its validity and applicability,respectively.

There are many influencing factors of bubble curtain clipping technology. In order to obtain the optimal combination of bubble curtain in engineering applications, AUTODYN software was used to design a three factor and three level orthogonal test. The average reduction rate of shock wave peak pressure was used as an evaluation index to study the influence and sensitivity of the number of bubble curtain layers, the burst distance of the bubble curtain and the charge depth on the bubble curtain clipping effect. The results indicate that the clipping ability of the bubble curtain has a great value, and there will be a negative effect if the number of bubble curtain layers continues to increase. The number of bubble curtain layers has the greatest effect on the clipping ability, followed by the charge depth, and the effect of bubble curtain explosion center distance is the smallest. The smaller the burst center distance and the greater the depth of the packet, the better the bubble curtain chipping effect. When the number of bubble curtain layers is 2, the bubble curtain burst distance is 1 m, and the charge depth is 10.5 m, the clipping effect is the best. [ABSTRACT FROM AUTHOR]

Addressing the problem of wireless physical layer security transmission for finite alphabet input systems,a spatial modulation secure transmission method is proposed.On the basis of information theory,the method utilizes the receive antenna indices of multiple-input multiple-output (MIMO) system to bear information,and randomizes the eavesdropper’s equivalent channel by switching the receive antennas,which can guarantee physical layer security transmission.First,the different receiving performances of the legitimate user and eavesdropper are analyzed in the spatial modulation secure transmission system.Second,the mutual information and secrecy mutual information of the transmission system are calculated,and two sufficient conditions that ensure positive secrecy mutual information are pointed out.Finally,an estimation algorithm of mutual information is provided.Moreover,the symmetry of finite alphabet set is exploited to decrease the computational complexity.Theoretical analysis and numerical simulation results verify the availability of the security transmission method.

In the amplify-and-forward (AF) relay systems，the confidential information forwarded by the relay can be intercepted by the eavesdroppers.For guaranteeing the secure communications，an artificial noise aided secure beamforming method is proposed.The goal is to maximize the secrecy rate of the system by jointly designing the beamforming matrix and the artificial noise (AN) covariance matrix at the relay subject to the total power and the per-antenna power constraints.This non-convex secrecy rate maximization (SRM) problem can be recast as a two-level optimization problem.The outer part can be solved by performing a one-dimensional search，and the inner part can be handled by the semidefinite relaxation (SDR) technique and interior-point methods.It is shown that there always exists a rank-one optimal solution for the SDR problem，i.e.，the relaxation is tight to the original problem.Simulation results demonstrate that the proposed method can improve the security performance of the system significantly.

The existing eavesdropping method has poor anti-noise performance and high complexity, which makes it not practical. It is shown that the received scrambled signals are distributed within parallel hyperplanes if adequate antennas are equipped by eavesdropper. According to this distribution, a hyperplane clustering (HC) algorithm was presented to blindly estimate the hyperplane parameters which reveal the sending information. Simulation results show that the HC algorithm, compared with the existing MUSIC-like algorithms, holds the advantages of better anti-noise performance and lower computing complexity.

Approaches generating secret keys based on radio channel characteristics can’t guarantee the key length and system efficiency at the same time because of the low entropy rate or high disagreement ratio of keys.An adaptive key distillation scheme based on the quantization of channel state information was designed.An upper bounding function was used as an approximation of the real one to improve the entropy of keys under the constraint of disagreement rate.Based on this,the key agreement scheme resulting in longer keys was selected.Simulation results show that with this scheme,the length of key and efficiency of the system can be guaranteed at the same time.

Linear randomization pre-processing framework was presented to design feasible ysical layer secure trans-mission schemes. The framework show that, based on characteristic differentiae of wireless channels, additive and mul-tiplicative randomization modules with suitable design would create channel advantage for legitimate users. In the view point of information theory security, the optimal distributions of the additive randomization weights and the multiplica-tive randomization weights to induce the lowest information leakage to the eavesdropper were verified. Finally, A random sub-carrier referencing security scheme was proposed as an instantiation analysis for the optimization design of multip-licative randomization weights.

An OFDM security model and a physical layer security transmission scheme were proposed for multi-carrier systems to achieve low probability of interception.In contrast to the resource allocation algorithm which would be disabled at the low SNR,this method designed the subcarrier transmission weighting vectors to randomize the eavesdropper’s signals but not the authorized receiver’s signals.The channel state information was the only character to distinguish authorized receivers and eavesdroppers,which was conducted to guide the weighting vectors design.Simulation results show that the proposed method guarantees that authorized receiver performs transmitted reference demodulation successfully,while the eavesdroppers can not detect the transmitted symbols.

Adding artificial noise in the MISO system was an effective method to improve the security.The transmit power allocation and artificial noise generation was mainly discussed.An artificial noise model of MISO system was presented,in which the artificial noise was regarded as additive channel noise.It was proven that when the artificial noise was distributed on Gaussian distribution,the secrecy capacity of MISO system was maximized,and the expression of this secrecy capacity was deduced.Considering the transmit power constraint and using the vector space projection method,The optimum power allocation is obtained.Given a power allocation,the artificial noise is generated by Box-Muller transformation,which was distributed on Gaussian distribution.And with the vector projection method,the artificial noise meets the optimum power allocation.

In order to enhance the spectrum efficiency in heterogeneous wireless networks,the idea of dynamic spectrum allocation (DSA) used in cognitive radio was introduced into the heterogeneous wireless networks,the idea of vertical handoff for multi-mode mobile users was introduced into the base station side,thereafter,the shared carrier vertical network transformation (SCVNT) algorithm in heterogeneous wireless networks was proposed.The theoretical analysis and simulation results show that SCVNT algorithm can effectively enhance the total channel efficiency in heterogeneous wireless networks,improve fairness in resource allocation,and will be able to achieve smooth upgrade,which is of a relatively high application value.

The detection of genetically modified (GM) crops provides important technical support for the safety management of agricultural genetically modified organisms (GMOs). Loop-mediated isothermal amplification (LAMP) technology is easy to operate, efficient, sensitive, and specific. It has been widely used in the detection of GM crops. This article analyzes and summarizes the application of LAMP technology in the detection of GM soybean, maize and rapeseed in recent years, hoping to provide scientific references for further application and standardization of LAMP technology in the detection of GM crops. [ABSTRACT FROM AUTHOR]

Environmental safety standards for agricultural genetically modified organisms (GMOs) has become an important technical support for the safety management of GMOs in China. By January 2021, the Ministry of Agriculture/Ministry of Agriculture and Rural Affairs had released 47 environmental safety standards for agricultural GMOs. This paper summarizes the status quo of China's agricultural GMOs environmental safety standards system, and comparatively analyzes the development of agricultural GMOs environmental safety standards in the domestic and foreign, and discusses the development direction of agricultural GMOs environmental safety standards system construction in the future. We hope to provide reference for further improvement of China's agricultural GMOs environmental safety standards, which will provide better technical support for its safety management. [ABSTRACT FROM AUTHOR]

To effectively improve the damping performances of the vehicle active suspension and reduce the energy consumption of the control system, an adjustable damping hybrid active suspension structure was put forward based on the ball screw actuator and magnetorheological damper. The 2-DOF dynamic model of the hybrid active suspension and the magnetorheological damper/ball screw actuator mathematical models were established. The optimal shock absorber damping value of the hybrid active suspension was analyzed, and corresponding adjustable damping switching controller under different speeds was designed. The damping performances and energy consumption characteristics of the hybrid suspension under driving cycles were simulated by MATLAB/Simulink software, and the bench tests of the hybrid suspension system were conducted. Numerical and experimental results show that compared with the active suspension, the root mean square of the body acceleration of the hybrid suspension decreases by more than 16% for random road. The damping effect of the hybrid suspension system is obvious. [ABSTRACT FROM AUTHOR]

This paper proposed the concept of impact factor of grid density (IFGD) which considered the overall effect of neighbored grids by the weight setting, and more appropriately represented the relative density of the current grid. Then, it used IFGD to identify relatively high density grid cells in clusters with different densities. The clustering process started from one of relatively high density grid cells and extends to its neighbors to form a skeleton of the clustering. Finally, it recognized and extracted the points of boundary grid to improve the quality of the clustering. Experimental results show that the algorithm can discover clusters with various shapes, recognize the boundary point and obtain the better multi-density clustering results. [ABSTRACT FROM AUTHOR]

Objective: To investigate the role of Hes1 in migration, invasion and epithelial-mesenchymal transition in cervical cancer cells. Methods: Real time quantitative PCR(RT-qPCR) and Western blotting were used to detect the expression of Hes1 in four cervical cancer cell lines. Hesl knockdown was performed by siRNA. The effects of down-regulation of Hes1 on migration and invasion in cervical cancer cells were evaluated by transwell assays. The main factors of epithelial-mesenchymal transition effected by Hesl knock down were measured by RT-qPCR and Western blotting. Results: The expressions of Hesl mRNA in four cervical cancer cell lines showed statistic differences (χα=10.39, P=0.016). Knockdown of Hes1 led to statistic differences in the numbers of cell passing through the chamber, between SiHa NC group and SiHa 1 group, HeLa NC group and HeLa 1 group (P<0.05, both) in both migration assays and invasion assays. After Hes1 RNA interference, compared to blank and negative control, the expression of E-cadherin was significantly reduced in SiHa and HeLa (both P<0.05), while ZEB1, Slug were induced in SiHa (both P<0.05), and vimentin, Slug were induced in HeLa (both P<0.05). Conclusions: Hes1 may have a role in suppressing migration and invasion in SiHa, HeLa cells, and subsequent down-regulation induces the epithelial-mesenchymal transition, thereby suggesting a possible role in migration and invasion of cervical cancer cells mediated by epithelial-mesenchymal transition. [ABSTRACT FROM AUTHOR]

In this paper, an optimal control problem based on carbon emission is analyzed. The carbon emission of a country follows a process deduced from the Gross Domestic Product (GDP), which follows a geometric Brownian motion, and the population of the country, which satisfies the Logistic model. A policy is utilized to reduce the CO2 emission of the country, resulting in some related costs. The country aims at reducing the carbon emission while minimizing the relevant costs contemporarily. The problem can be solved in the framework of stochastic control and Hamilton-Jacobi-Bellman (HJB) equation. Via Cole-Hopf transformation, the quasi-linear equation can be linearized and solved explicitly, and the optimal policy and minimal cost can be derived afterwards. Some numerical results are provided, and the relationships between the value functions and different parameters are analyzed. Furthermore, we analysed the case in which an upper bound is put on the control policy. Since the equation cannot be solved explicitly, a numerical solution is presented, showing the properties of the value function and the optimal policy. [ABSTRACT FROM AUTHOR]

Objective To observe the short-term clinical effectiveness of bone ring graft technique and to summarize the key points of related surgical operation to provide comprehensive clinical guidelines. Methods Fifteen patients with severe alveolar bone absorption were selected to receive bone ring grafting and immediate dental implant. Final fixed prostheses were cemented five months after initial implantation. Cone beam CT scans were conducted on all subjects before the procedure, as well as four months post-operation to evaluate alveolar bone height and level of bone height and absorption around the implants. Four to six months after prosthesis installation, each implant's Jemt classification, gingiva attachment, and probing depth (PD) were analyzed. The difference of PD between implants and adjacent teeth, as well as the difference of the bone absorption between labial and lingual sides, was compared. The survival rate of the bone ring and the retention rate of implants were calculated. Complications and patient satisfaction were also investigated. Results Bone graft survival rate was 94.4% and dental implantation retention rate was 100% four months post-operation. Average bone level increase was (6.06±1.06) mm, average bone absorption was (1.33±0.84) mm, and average bone thickness at the neck of the dental implant body was (6.94± 0.73) mm. Approximately 4 to 6 months after crown restoration, average bone level increase was (5.62±1.03) mm, average bone absorption was (1.51±1.02) mm, and average bone thickness at the neck of the dental implant body was (6.77±0.72) mm. The PD around the implant body and the adjacent teeth was statistically insignificant. No major post-operative complication was observed, restorations were successful, and patient satisfaction level was high. Conclusion Bone ring graft technique and immediate dental implantation are relatively simple to perform, and these techniques facilitate reduction in required treatment time. Short-term effect is reliable and satisfactory, whereas long-term outcomes require further follow up and study. [ABSTRACT FROM AUTHOR]

Based on rubber spring theory and constitutive model, performances of rubber spring were investigated by some methods like experiment and finite element analysis. Get the load-displacement curve of compression stiffness and damping stiffness of rubber spring through the test. Fit test results curves in different constitutive models, by the curve error which get through comparative analysis of the fitting curve and the original test curve to determine the most suitable constitutive model of rubber spring is 5 parameters Mooney-Rivlin constitutive model. Based on the appropriate constitutive model, the accuracy of rubber spring was verified on stress-strain response by finite element analysis to validate the accuracy of the finite element analysis. Provided favorable theoretical basis and experimental verification for the future analysis and calculation through the study which found distinguish point of the rubber spring linear and nonlinear, non-linear changed characteristics in stiffness and the most suitable rubber spring constitutive model which obtained by experiments. [ABSTRACT FROM AUTHOR]

PURPOSE: To explore a method of attached gingiva reconstruction around dental implants and to evaluate its clinical outcomes and technical characters. METHODS: From January 2011 to August 2011, a total of 10 implants were included in this study from 8 patients who had inadequate attached gingiva and needed to undergo secondary operation. A modified apically positioned flap technique was applied to reconstruct attached gingiva at the time of secondary operation. Crown restoration was finished 4 weeks after the operation and the patients were recalled 6 months after restoration. Effective keratinized mueosal width was recorded separately before the operation, 4 weeks after the operation and 6 months after restoration. Clinical examination was conducted 6 months after restoration including modified plaque index(mPI), probing depth (PD), bleeding index (BI) and percentage of bleeding on probing. Statistical analysis was performed using Wileoxon signed rank test with SPSS18.0 software package. RESULTS: Four weeks after the operation, there was an average increase of 2.41 mm in effective keratinized mucosal width compared with the preoperative value (P<0.05). After 6 months of function, the newly formed keratinized mueosa remained stable and attached to the crown tightly without obvious inflammation. The mean width was (2.64 ± 0.53) mm. Clinical examinations showed a mean mPI of 0.70 ± 0.82, a mean PD of (1.80 ± 0.36) mm, and a mean BI of 0.73 ± 0.64. In terms of bleeding on probing, 23.3% of sites showed positive outcome. CONCLUSIONS: By using the modified apieally positioned flap technique at the time of secondary operation, the attached gingiva around implants can be effectively reconstructed. The short-term effects are satisfactory. [ABSTRACT FROM AUTHOR]

Objective The aim of this study is to optimize conditions for labeling human periodontal ligament stem cells (PDLSCs) using enhanced green fluorescent protein (eGFP) infected by lentivirus vector and to obtain PDLSCs with high stable expressed eGFP. Methods PDLSCs were transfected with eGFP by lentivirus vector for 48 h via dif-ferent multiplicity of infection (MOI) (25, 50, 100, 200 and 400) and the infection efficiency were analyzed by both fluorescent microscope and flow cytometry. The proliferation rate of infected PDLSCs was evaluated by MTT. The in-fected PDLSCs were further for detection of pluripotent, differentiation ability and alkaline phosphatase (ALP) expression ability. Results The infection efficiency for each group were 44.7%, 60.9%, 71.7%, 85.8% and 86.9% respectively. Proliferation of PDLSCs was not affected when MOI was below 200; however, at MOI 400, the proliferation ability was affected compared with control group. The pluripotent and ALP abilities of PDLSCs were not changed by the infection. Conclusion Infection for 48 h at MOI 200 is optimal for labeling PDLSCs with eGFP using lentivirus vector, and the proliferation and differentiation abilities of PDLSCs are not affected obviously. [ABSTRACT FROM AUTHOR]

Objective To establish three-dimension finite element model of mandible with two kinds of Replace im-plant, and to study stress of implant and abutment. Methods The data of components of the dental implant was measu-red, cross section of the mandible was scanned by spiral CT and image reconstruction technique was conducted. Three-dimension finite element analysis software UG and MSC. Marc/Mentat were used to built the conjunction model and bone model of two implant systems. Axial loading (200 N) and 30° oblique loading (100 N) were applied on the models respec-tively, the stress distribution patterns of the implant and abutment of two implant systems were analyzed. Results The peak stress district was concentrated on the structure of the implant cervix, which was more obviously displayed on the Replace Select implant. The peak stress of oblique loading was higher than that of axial loading. The peak stress on the implant cervix of Replace Select implant was higher than that of Replace External Hex implant in all loadings. Conclu-sion To Replace Select especially, obliq force should be avoided on clinical practice in case of the implant fracture. [ABSTRACT FROM AUTHOR]

Objective: To construct the stable transfection Hela cell lines with lentiviral vector which may interfer the expression of ALDH-1,and to further explore the biological characteristics between the expression of ALDH-1 and Hela cell lines. Methods: Hela cells were cultured in vitro, added the different concentration of puromycin to screen, and to determine the best screening concentration; Hela cells were tested from 24-well plates, threw away the old culture medium, and added 400 µL of new medium to the plates, and then added four kinds of lentivirus solution) ALDH-1, ALDH1-1719, ALDH1-740, ALDH1-921,and there was a kind of lentivirus which has the best interfering effect) and one kind of negative control lentivirus solution (LV3-NC) to the plates, at last added Polybrene liquid to them. Every lentivirus solution volume was added about 50 µL (each of viral titers were 1x10-8 TU/mL), and the Polybrene was added about 0.5 µL (concentration of 5 mg/L) respectively. Fresh culture medium was changed after 24 hours, and observe the fluorescence after 72 hours. At last, using the best screening concentration ofpuromycin to screen the transfection Hela cells, and to get the stable transfection cell lines. Results: The best screening concentration of puromycin was 0.9 mg/L, lentiviral vectors were successfully transfected into Hela cells, and the stable transfected cell lines were successfully obtained after two weeks. Conclusions: Hela cells which has stable interference of ALDH -1 were successfully constructed. [ABSTRACT FROM AUTHOR]

Aiming at the problems of slow channel changes and low key generation rate in IoT quasi-static scenarios, a key generation method based on reconfigurable intelligent surface (RIS) was proposed.First, the agility characteristics of RIS was used to construct a fast-changing channel.Then, the base station and legitimate users extracted a consistent key from the channel information through channel estimation, conversion, and information negotiation.Finally, optimal time allocation for data transmission and key generation in the coherent time to achieve the maximum transmission rate of one-time pad.The simulation results show that the key generation rate of proposed method is higher than that of the existing relay-assisted method, random signal flow method and random number method, and as the number of RIS reflection units and frequency of channel estimation in the coherence time increase, the key generation rate will be further improve.

The theory of kidney storing essence storage, an important part of the basic theory of traditional Chinese medicine(TCM), comes from the Chapter 9 Discussion on Six-Plus-Six System and the Manifestations of the Viscera in the Plain Questions, which says that &quot;the kidney manages closure and is the root of storage and the house of Jing(Essence)&quot;. According to this theory, essence is the fundamental substance of human life activities and it is closely related to the growth and development of the human body. Alzheimer's disease(AD) is one of the common neurodegenerative diseases, with the main pathological features of Aβ deposition and Tau phosphorylation, which activate neurotoxic reactions and eventually lead to neuronal dysfunction and cell death, severely impairing the patient's cognitive and memory functions. Although research results have been achieved in the TCM treatment of AD, the complex pathogenesis of AD makes it difficult to develop the drugs capable of curing AD. The stem cell therapy is an important method to promote self-repair and regeneration, and bone marrow mesenchymal stem cells(BMSCs) as adult stem cells have the ability of multi-directional differentiation. By reviewing the relevant literature, this paper discusses the association between BMSCs and the TCM theory of kidney storing essence, and expounds the material basis of this theory from the perspective of molecular biology. Studies have shown that TCM with the effect of tonifying the kidney in the treatment of AD are associated with BMSCs. Exosomes produced by such cells are one of the main substances affecting AD. Exosomes containing nucleic acids, proteins, and lipids can participate in intercellular communication, regulate cell function, and affect AD by reducing Aβ deposition, inhibiting Tau protein phosphorylation and neuroinflammation, and promoting neuronal regeneration. Therefore, discussing the prevention and treatment of exosomes and AD based on the theory of kidney storing essence will provide a new research idea for the TCM treatment of AD.