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In order to improve the utilization rate of wood and solve the shortcomings of low density, low strength, and easy shrinkage deformation of artificial fast-growing forest. In this study, the artificial fast-growing poplar was taken as the research object, and the unique mineral hexagonal stone in Inner Mongolia Autonomous Region was used as the modified material. The hexagonal stone was impregnated into the wood by vacuum pressurized impregnation modification technology, and then the properties of modified wood were tested and characterized. The results showed that the optimum impregnation times of poplar wood modified by hexacyclic stone were 8 times. The single impregnation process was vacuum impregnation for 120 min, atmospheric pressure impregnation for 5 min, and then absolutely dried. The average weight gain rate and liquid absorption rate of the modified wood were 15.33% and 146.37%, respectively. The air-dry density and total dry density of the modified wood were 23.25% and 21.95% higher than those of the raw materials, which provided new ideas for the preparation and utilization of modified wood. [ABSTRACT FROM AUTHOR]

This paper presents a real-time system for 3D recovery of dynamic scenes by using multiple FPGA-based RGBD imagers. The RGBD imager developed in our lab produces color images combined with the corresponding dense disparity maps encoding depth information. Multiple RGBD imagers were externally triggered to sense the 3D world synchronously. To improve the quality of the acquired depth map, a probabilistic method for fusing depth maps from multiple RGBD imagers with sparsely distributed viewpoints was proposed. The fused depth maps of a dynamic scene from multiple viewpoints were then streamed to a PC cluster to generate the 3D point cloud of the dynamic scene in real time. Experimental results show that our system is very promising for the 3D recovery of large scale dynamic scenes with multiple moving objects. [ABSTRACT FROM AUTHOR]

A license plate character segmentation method based on multiple scale templates matching and part-based model was proposed to improve the precision of license plate character segmentation. Characters of single layer plates were extracted by sliding the multiple scale templates, which were designed according to the structures of the plates, in the plate candidate area. The double layer plates were modeled by part-based model, the top layer and the bottom layer are the two parts in the model. Candidates of the two parts were obtained by the multiple scale templates matching, and the geometrical constraint between the two parts was used to get the final segmentation result of the characters. The experiment results indicate that the proposed approach can segment characters for both single layer plates and double layer plates effectively. [ABSTRACT FROM AUTHOR]

Presented a robust and efficient video-based vehicle tracking method based on moving object detection to handle the dynamic illumination changes, shadow and occlusion in complex traffic scene. Firstly, an adaptive background modeling was adopted to detect the moving regions. Secondly, shadow reduction was used to obtain exact moving area. Then, an occlusion resolving strategy was proposed to handle the occlusion. Finally, vehicle tracking was achieved by region correspondence, combined with Kalman filters to model the motion of vehicles and optimize the vehicle parameters. The experimental results demonstrate that the proposed vehicle tracking method can effectively resolve shadow and occlusion problems in complex and variable outdoor scenarios, and robust vehicle tracking can be achieved. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the mutational effect of endotoxin (ET)-induced mtDNA and protection effect of cation A (CA) in rats.

In order to carry out a reliable control for a semi-active suspension system of an engineering vehicle, a mathematic model of single chamber hydro-pneumatic spring was established. The characteristics of spring rate and damping rate as well as the relationship between throttle area and damping force were analyzed. The control strategy of improving vehicle ride comfort without the frequent suspension breakdown was proposed. The fuzzy logic control (FLC) model with the inputs of suspension deflection and its change rate with time was established. The rules of fuzzy logic control were worked out and the fuzzy logic controller was designed. The responses were simulated under the conditions of road surfaces with sine, integrated random white noise and instant step input excitation, respectively. According to simulation results, the application of FLC in semi-active suspension controlling not only reduces the frequency of suspension breakdown, but also improves the ride performance from statistic point of view. [ABSTRACT FROM AUTHOR]

This paper presents a novel particle-based pedestrian tracking algorithm for PTZ camera surveillance. Most of the state-of-art particle-based tracking algorithms are challenged due to lacking of a reliable moving object detection and drastic scale along with perspective shift of the target. Therefore, pure intensity based algorithms usually miss the target gradually without other features for correcting target location. Our method learns and maintains a contour template of the target besides intensity. Taking into account both the evolution and sudden change of the pedestrian contour, the proposed tracking algorithm maintains several sets of profiles from different perspectives and evolves them incrementally. The effectiveness of our tracking algorithm with extra contour measurement has been tested over several surveillance records captured from PTZ camera. Compared with other cutting edge tracking algorithms, this presented algorithm could estimate the target location more robustly. [ABSTRACT FROM AUTHOR]

In order to solve the problem of excessive temperature rising of damper in military vehicle suspension system that could lead to oil leakage and finally cause the damper invalidation, a comprehensive model is proposed innovatively in this work. The proposed model includes mechanical dynamics of the vehicle suspension system coupled with its thermal properties. Moreover a thermal-mechanical coupled model was established by using Matlab/Simulink, which reflected the closed-loop positive feedback system. Under the conditions of different suspension parameters and operating modes, the curves to reveal the damper temperature rising characteristics were obtained by simulation and computation. Research results show that: along with the decline of road rank, the more increase of vehicle velocity, unsprung mass or load wheel stiffness, the higher the damper temperature is. Furthermore sprung mass and suspension stiffness have no effect on the damper temperature rising characteristic. [ABSTRACT FROM AUTHOR]

Taking seven types of slopes in the disturbed area of Xiangjiaba construction as test objects, this paper measured their soil pH, and evaluated their soil fertility with standard integrated grade method. The soil at vegetation-growing concrete gunning (VGCG) was weakly alkaline, while the others were acidic at different degree. The soil pH value was decreased in the sequence of VGCG (7-68±0.04) > discarded residue (DR) (6.96±0.02) > framed beams with soil cover (FBSC)(6.93±0.16)> external soil with spray seeding (ESS)(6.75±0.35) > thick layer substrate (TLS)(6.67±0.36)> natural secondary forest (NSF)(5.68±1.25)> natural forest (NF) (4.71±0.23); while the integrated index of soil fertility was in the order of VGCG (3.06±0.02)< TLS(4.06±0.78) < NSF(4.52±0.16) < FBSC(4.62±0.06) < NF(4.62±0.06) < ESS(4.90± 0.01)< DR(5.00±0.10). It proved that some artificial additives such as cement, compound fertilizer, and humus had definite positive effects in adjusting soil pH and maintaining soil fertility, being helpful to provide favorable soil condition for plant growth [ABSTRACT FROM AUTHOR]

In this paper, a new algorithm based on graph cuts to solve stereo matching problem is proposed. In the algorithm, the constructed graph for minimizing the energy function does not use any auxiliary nodes, therefore smaller graph can be constructed efficiently and the minimum cut can be computed faster. Experimental results demonstrated that satisfactory results can be computed efficiently by the proposed method. [ABSTRACT FROM AUTHOR]

Waxy wheat is the new variety for special purposes first proposed by Ministry of Agriculture and Rural Affairs of the People’s Republic of China in 2017. In order to better understand the characteristics of waxy wheat, we have studied the grain and starch characteristics of Shannong nuomai 1, which was the first high-yield waxy wheat approved by Shandong Province. The results showed this variety hardly contained any amylose (only 0.158%), but had the high protein content (16.4%) and flour whiteness (81.2%). There were uneven starch particle size distribution with more A-type starch particles using scanning electron microscopy. In terms of pasting properties, a lower gelatinization temperature, shorter gelatinization time, lower peak viscosity, final viscosity when comparing with those of common wheat. The water absorption rate of dough was obviously higher than that of common wheat, and the formation time was longer than stability time. These studies could provide reference and theoretical basis for power blending and processed products with Shannong nuomai1.

The precision machining of the threaded cartridge relief valve sleeve is a manufacturing process of grinding after carbonitriding. The shape and position error of inner cone will affect the service life and static and dynamic characteristics of the relief valve. This requires the need of manufacturing process to accurately control the error of the inner cone. Based on the process analysis, a manufacturing error model was established and applied to obtain a reasonable error range of the inner cone angle and to determine the relationship between the inner cone angle error and the grinding amount. According to the structural characteristics of the valve sleeve, a special detection device was designed and the detection principle and measurement error were analyzed to improve the detection accuracy through error proofreading. After heat treatment, the valve sleeve was divided into axial size groups and the unified principle of datum was adopted to ensure the stability of grinding accuracy. According to the detection principle and error model, the error calculation of the grinding test piece was carried out, and the grinding parameters were adjusted accordingly to make a qualified manufacturing error. In the subsequent manufacturing, the axial dimension of the detection sealing circle of the valve sleeve is quickly measured by the detection device, so that the manufacturing error falls within the control range, ensuring the controllability of the batch production. Based on the design and process parameters of a relief valve, results reveal that the control error of the inner cone’s own angle should be ±0.8°. The corresponding maximum grinding tolerance value of the axial direction of the sealing circle is 0.186 mm, while the corrected minimum grinding tolerance is 0.075 mm. Through experiments, the accuracy of the error model is verified. The angle measurement error of the detection method is 0.06°, while the measurement error of the axial dimension of the sealing circle is 2 μm. The deviation of the maximum grinding amount and the minimum grinding amount range caused by the angle measurement error is compensated by the shrinkage of the actual manufacturing error of the inner cone angle. The theory and method also provide a systematic process for manufacturing control and reverse engineering of the other inner cone.

Grain and oil quality sampling is an important work in grain trading, storage and processing. To reserve the process sample and test the quality have important sense to guarantee fair trade and control grain quality in grain storage and processing. To resolve the problem in field grain quality sampling such as lack of regional representation, process fraud and difficulty in grassroots organization building, a field grain quality sampling management mode and relative techniques based on GIS and cloud platform was provided in this article. It not only standardized the sampling process, but also realized a real-time recording and monitoring of sampling process, ensured a fair and just sample testing process, reduced fraud in the process. The sampling and testing result can be easily handled in a visible and direct way. The management style of platform rental can solve the problem of construction fund and technicians shortages at the grassroots level.

Through the collection and collation of latest information and relevant standards about Cereals,Oils and their products, the general situation of International Standardization Organization (ISO) standard system were introduced in this paper, and the classification, status quo, characteristic distribution and latest development trend of oil seed, fruit and oilseed meal, grain and beans, animal and vegetable oil standards in ISO grain and oil standard system were also introduced and analyzed systematically. The analysis results showed that the framework structure of ISO grain and oil standard is reasonable, the standard system is perfect, the emphasis is on food quality and safety, and the management standard, comprehensive standard and safety standard will be the future focus of ISO. Based on the situation of China’s grain and oil standard system, this paper proposed to improve the international influence of China’s grain and oil standard from the aspects of expanding the coverage of the standard, standardizing the management of making and revising scientific standards, and introducing new science and technology. Therefore, understanding and adopting ISO standard and formulating grain and oil standards in line with the international standards are conducive to further improving the construction of China’s grain and oil standard system.

Objective To predict the pigmentation phenotypes of Chinese populations from different language families, analyze the differences and provide reference data for forensic anthropology and genetics. Methods The HIrisPlex-S multiplex amplification system with 41 loci related to pigmentation phenotypes was constructed in the laboratory, and 2 666 DNA samples of adult males of 17 populations from six language families, including Indo-European, Sino-Tibetan, Altaic, Hmong-Mien, Tai-Kadai and Austro-Asiatic language families distributed in different regions of China were genotyped. The pigmentation phenotype category of each individual was predicted using the online prediction system （https://HIrisPlex.erasmusmc.nl/）, and then the output data were statistically analyzed. Results About 1.92% of the individuals of Asian-European admixed populations from Indo-European and Altaic language families had blue eyes and 34.29% had brown or gold hair. The phenotypes of the color of eyes and hair of other populations had no significant difference, all individuals had brown eyes and black hair. There were differences in skin color of populations of different language families and geographical areas. The Indo-European language family had the lightest skin color, and the Austro-Asiatic language family had the darkest skin color; the southwestern minority populations had a darker skin color than populations in the plain areas. Conclusion The prediction results of pigmentation phenotype of Chinese populations are consistent with the perception of the appearance of each population, proving the reliability of the system. The color of eyes and hair are mainly related to ancestral components, while the skin color shows the differences between language families, and is closely related to geographical distribution of populations.

This paper reviewed the recent development of primary carbides in H13 steel from the aspects of solidification segregation theory, solidification method, production process, and alloy design. The relationship between the production process of H13 steel and the characteristics of primary carbides was clarified. During the solidification of H13 steel, primary carbides can be easily generated by dendritic segregation. The primary carbides in H13 steel can be divided into polygonal, stripy, blocky, and eutectic structures according to the different shapes and can be divided into MC, M2C, M7C3, and M23C6 according to the different structures. The primary carbides can also be classified as Mo-rich, V-rich, and Ti/Nb-rich carbides according to the different compositions. Primary carbides are detrimental to the performance of H13 steel because cracks can easily form around primary carbides during service of the materials. The widely used methods of controlling the primary carbides in H13 steel under industrial production conditions, including solidification control, modification treatment, high-temperature diffusion of the ingot, and alloy composition optimization, were introduced. Modification treatment and solidification control are able to control the size and quantity of primary carbides but are unable to avoid the precipitation of primary carbides entirely. The stability of primary carbides can be relieved by composition optimization. High-temperature homogenization treatment of ingot is the most important means of controlling primary carbides in H13 steel. However, the heating temperature and holding time need further investigation.

A 6005A aluminum alloy was produced by an actual surface with less defects, multiple defect samples, and as-ground samples for the purpose of investigating the effect of aluminum alloy surface damage on corrosion resistance and its corrosion electrochemical behavior in seawater. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were employed in order to characterize the surface states of the 6005A aluminum alloy. The results show that the surface defects caused by aluminum alloy products consist mainly of scratches. With the increase of surface defects, an obvious increase in Ra is observed, and Ra could quantitatively describe the severity of surface damage. In simulated seawater, the 6005A aluminum alloy undergoes comprehensive corrosion and pitting; thereby, corrosion resistance deteriorates as the amount of defects increases. Electrochemical test results show that the larger the number of surface defects is, the greater are the roughness and lower corrosion potential. Additionally, the greater the corrosion current density is, the worse is the corrosion resistance. A 6005A aluminum alloy that has suffered surface damage and whose corrosion resistance was affected due to seawater can cause the following:the more surface defects are, the greater is the roughness and surface film damage; thereby, the plastic deformation of the surface becomes more serious. The protective layer of the oxide filmis reduced, and the substrate has a higher corrosion rate. The passive film for the samples with less defects is more compact and uniform and could protect the substrate, while effectively reducing further corrosion.

In-situ research was conducted to illuminate the high-temperature behavior of primary carbide in H13 steel that had been cast in different ways. Experimental observations indicate the obvious segregation of Cr, Mo, V, and C in the interdendrite zone of continuously cast and electroslag remelting (ESR) samples. In the interdendrite zone, primary carbide is composed of Cr, Mo, V, and Ti. A liquid phase was observed to occur around the primary carbide of two as-cast samples cast by continuous casting and ESR processes when heated to 1200℃ and 1250℃, respectively. The temperature at which the liquid phase appears agrees well with theoretical calculations. The liquid-phase region expands as the heating temperature increases and the continuous casting sample shows a larger liquid zone. The emergence of a partial liquid phase accelerates the diffusion of the segregated elements and is an important factor in the high-temperature behavior of primary carbide.

Optical microscopy (OM), scanning electron microscopy (SEM), and electron microprobe analysis (EMPA) were used to determine the nature of carbonitrides decomposition in H13 hot work die steel under high temperature, including its morphology, size and composition. Most of the original carbonitrides are long strip (Vx,Mo1-x)(Cy,N1-y) ranging between 10~30 μm with a few square (Tix,V1-x)(Cy,N1-y). The result shows that the edge of the carbonitrides becomes saw-toothed after holding at 1200℃ for 2.5 h, and fine decomposed particles are formed. The average length of carbonitrides, mainly (Tix,V1-x)(Cy,N1-y), is reduced to 12.9 μm as increasing the holding time for 10 h. When the steel is held at 1250℃ for 5 h, about 87% of the carbonitrides disintegrate, especially (Vx,Mo1-x)(Cy,N1-y) dissolving and disappearing, and the carbonitrides size is less than 20 μm. When holding at 1250℃ for 10 h, all the carbonitrides remained are (Tix,V1-x)(Cy,N1-y), of which 70% are square and 93% decompose to fine particles, and can be controlled to size below 10 μm. It is deduced that (Tix,V1-x)(Cy,N1-y) decomposition is related to Fe diffusion by EMPA analysis and that the Fe content in (Tix,V1-x)(Cy,N1-y) gradually enhances while Ti and V contents decline. The carbonitrides reliably decompose at the position of small curvature radius and defect position, forming fine particles of 0.1~1 μm. The original carbonitrides disappear by zone dissolution from outer to inner. The equilibrium temperature of carbonitrides dissolution has a relationship with its constituents based on the two-sublattice model, and dissolution temperature for most (Tix,V1-x)(Cy,N1-y) in sample is between 1200℃ and 1246℃, which fits well with the experimental results.

Three kinds of primary carbonitrides were classified in H13 hot work die steel through experiment,including (Vx,Mo1-x)(Cy,N1-y) rich in V and C,(Tix,V1-x)(Cy,N1-y) rich in Ti and N,and (Tix,V1-x)(Cy,N1-y) rich in V and C,some having a core in the center.The element variation and Gibbs energy of the carbonitrides during H13 solidification were analyzed based on the solidification segregation model and the two-sublattice model,taking the interaction between components into account as well as the alloying element content and C/N ratio of the three types of primary carbonitrides.It is found that Tiand N-rich (Tix,V1-x)(Cy,N1-y) forms when the solid fraction reaches 0.9,while the other Vand C-rich (Tix,V1-x)(Cy,N1-y) generates when the solid fraction is greater than 0.96 during solidification.The critical solid fraction for the formation of these two (Tix,V1-x)(Cy,N1-y) decreases with increasing Ti and N contents soluted in the carbonitrides.The formation of (Vx,Mo1-x)(Cy,N1-y) during solidification can be affected by the x value.The critical solid fraction decreases as less vanadium is soluted in (Vx,Mo1-x)(Cy,N1-y),leading to larger size carbonitrides demonstrated by the models,which fit well with experimental data.The influence of oxides and carbonitrides on heterogeneous nucleation for the carbonitrides was also researched through lattice misfitting analysis.

For the problem of attendance information inaccuracy of regular attendance methods in coal mine like card punching method, an automatic sign-in system for dispatch room staff of coal mine was designed by use of face recognition technology, and the whole design scheme and face recognition algorithm of the system were introduced. The system firstly collects and pre-processes the face image, then detects face by use of Adaboost algorithm, and lastly recognizes the detected face through POEM + block PCA algorithm and nearest neighbor classifier. The system realizes functions of automatic sigh-in and attendance record of dispatch room staff of coal mine, which provides basis information for staff appraisal.

Objective: To investigate the mid-term effect and complications of arthroscopic popliteal tendon suture in the treatment of lateral meniscus injury., Methods: From January 2016 to December 2020, the data of 57 patients with lateral meniscus popliteal tendon injury treated by arthroscopic popliteal tendon suture fixation were retrospectively analyzed, including 35 males and 22 females, aged from 18 to 47 years old with an average of (32.9±7.9) years old. Knee function was evaluated using the International Knee Documentation Committee (IKDC) and Lysholm scores both before the operation and at the final follow-up. Meniscus healing was evaluated according to the postoperative Barrett standard. Wound healing complications, such as vascular injury, nerve injury, and lower extremity venous thrombosis, were recorded., Results: All 57 patients were followed up for 12 to 58 months with an average of (38.1±14.9) months.The incisions of the patients after the operation were all Grade A healing without infection, popliteal tendon injury, blood vessel injury, nerve injury and lower extremity venous thrombosis.The IKDC score increased from (49.7±3.6) points preoperatively to (88.5±4.4) points in the final follow-up ( P <0.05). The Lysholm score increased from (48.8±4.9) points preoperatively to (91.9±3.9) points at the final follow-up ( P <0.05). At 3, 6 months and 1 year after operation, according to Barrett's criteria, 54 cases were clinically healed, the healing rate was 94.7% (54/57)., Conclusion: This study preliminarily confirmed that arthroscopic suture technique can result in clinical stability through suture and fixation of the meniscus in the injured lateral popliteal tendon area. No adverse effects on knee joint function were found in the mid-term follow-up after the operation.

The shoulder joint is the most flexible joint in the body with the largest range of motion, and the movement pattern is more complex. Accurate capture of three-dimensional motion data of the shoulder joint is crucial for biomechanical evaluation. Optical motion capture systems offer a non-invasive and radiation-free method to capture shoulder joint motion data during complex movements, enabling further biomechanical analysis of the shoulder joint. This review provides a comprehensive overview of optical motion capture technology in the context of shoulder joint movement, including measurement principles, data processing methods to reduce artifacts from skin and soft tissues, factors influencing measurement results, and applications in shoulder joint disorders.

Superior labrum anterior posterior (SLAP) injury is a major challenge for orthopedic surgeons, due to the poor healing ability of the injured labrum. Although arthroscopic surgery is the gold standard for the treatment of SLAP injury, there are still disputes about the adaptation of different surgical techniques, the choice of anchors during operation, knotted or knotless anchors, and fixation methods. The authors believe that arthroscopic repair of SLAP lesions is effective for young patients with intact glenoid labrum(<35 years old) or with extensive activity, where single and knotless anchor is preferred. For the older patients(≥35 years old) with degeneration and wear of glenoid labrum, biceps tenodesis is more preferable, and interference screw fixation technique is recommended. As for patients with failed SLAP repair, biceps tenodesis can achieve a high success rate as a revision surgery. By review of the relevant literature in recent years, this paper summarizes the adaptation of different surgical methods of arthroscopic treatment of SLAP injury, intraoperative anchoring techniques, fixation methods and other improved surgical techniques.

The surgical treatment of massive rotator cuff tears is a clinical challenge for orthopaedic surgeons. Moreover, tendon retraction, adhesions and fatty infiltration after rotator cuff tear will further increase the difficulty of surgical repair. Therefore, it has become a hotspot and difficulty to repair massive rotator cuff tears with a better way in current research. In recent years, with the continuous development of arthroscopic techniques, shoulder arthroscopic surgery has become the gold standard for the treatment of massive rotator cuff tears, but the adaptations, effects and combined application of different surgical methods are still controversial. The author believes that arthroscopic debridement of shoulder joint and acromioplasty or tuberoplasty could relieve shoulder pain in the short-term for elderly patients with lower functional requirements;long biceps tenotomy or tenodesis is effective for patients with biceps long head tendon injury; complete repair is still the first line treatment for massive rotator cuff tears, but partial repair is possible for massive rotator cuff tears that could not be completely repaired;patch augmentation technology could bring good results for young patients with high functional requirements;for patients with limited internal and external rotation of the shoulder joint and high functional requirements, tendon transfers surgery is recommended;superior capsular reconstruction is more advantageous for young patients with no obvious glenohumeral arthritis, better deltoid muscle strength and higher functional requirements. In addition, subacromial spacer implantation has become a current research hotspot due to its advantages of small trauma, low cost and relative safety, and its long-term effect still needs to be further confirmed.

Objective: To investigate the method and clinical effects of the treatment of recurrent shoulder dislocation with severe glenoid injury by arthroscopic subscapularis augmentation., Methods: From March 2019 to August 2020, 16 patients with recurrent dislocation of shoulder with severe glenoid injury underwent arthroscopic subscapularis augmentation, including 10 males and 6 females, aged from 18 to 50 years old with an average of (29.06±10.54) years old, 4 cases of left shoulder and 12 cases of right shoulder.Visual analogue scale (VAS), American Shoulder and Elbow Surgeons (ASES) score and Rowe score were used to evaluate shoulder function and stability before and after operation., Results: All the 16 patients were followed up from 12 to 29 months, with an average of (18.75±7.26) months. VAS score decreased from 5.25±1.13 before operation to 1.37±0.65 at the final follow-up;ASES score increased from 59.44±9.93 before surgery to 90.88±4.00 at the final follow-up; Rowe score of shoulder increased from 51.56±8.89 before surgery to 92.19±7.06 at the final follow-up, and the differences were statistically significant ( P <0.05). No dislocation was observed during follow-up. No clinical complications such as incision infection, vascular and nerve injury occurred in all patients after operation., Conclusion: Arthroscopic subscapularis augmentation in the treatment of recurrent dislocation of shoulder with severe glenoid injury is satisfactory. It is an effective treatment method of recurrent dislocation of shoulder joint with severe glenoid injury, and external rotation function in patients with almost unaffected.

The incidence of re-tearing after rotator cuff repair is very high. The main reason is that the tendon-osseous junction after the operation is scar healed. In response to this problem, research in recent years has focused on the application of grafts, including cell transplantation, periosteum transplantation, cartilage transplantation, and biosynthetic transplantation. Cell transplantation is mainly a variety of stem cells from different sources. The current research has confirmed that it can achieve better results. The combined application of exosomes and stem cells may be the future development direction. Periosteum transplantation is a promising intervention method, but few clinical applications at present, and there are problems such as limited sources of materials and secondary trauma from the materials. Tissue engineered periostium and artificial bionic periostium may be alternatives to periosteal;cartilage transplantation can promote the regeneration of cartilage at the tendon-osseous junction and facilitate tendon-bone healing. However, there are also limited materials and secondary damage. There is no better solution to this problem. The slow degradation of inorganic composites and the poor effect of single use limit its application; biological derivatives have immunogenicity, poor biomechanics and other issues, there is currently no proper solution; organic synthetic grafts pay more attention to simulating the structure of the physiological tendon-osseointegration zone, and show good results in tendon-bone healing, and have good application prospects. In addition, most of the above-mentioned application research of different grafts stays at the cellular and animal level, and more research is needed in clinical application. This article briefly reviews the application status, advantages, disadvantages and development trends of the above-mentioned different grafts, in order to provide certain guidance for the clinical treatment of rotator cuff tears.

Objective: To compare difference in clnical efficacy between arthroscopic double posterior internal approach and incisional surgery for acute simple posterior cruciate ligament tibial avulsion fractures., Methods: Totally 52 patients with acute simple posterior cruciate ligament tibial avulsion fractures treated from June 2016 to June 2020 were retrospectively analyzed and divided into two groups according to different surgical protocols, 27 patients in arthroscopic group were treated with arthroscopic double posterior internal approach, including 16 males and 11 females, aged from 19 to 52 years old, with an average age of (34.9±9.2) years old;25 patients in open reduction group were treated with posterior medial knee incision, including 14 males and 11 females, aged from 18 to 54 years old , with an average age of(33.7±8.4) years old. Operation time, incision length, intraoperative bleeding, hospitalization days, hospitalization cost, fracture healing, complications, postoperative Lysholm score and IKDC score at 12 months were observed and compared between two groups., Results: All patients in both groups were completed opertaion successfully without vascular or nerve injury, and 52 patients were followed up from 6 to 24 months with an average of (15.0±1.7) months. Operation time and hospitalization cost in arthroscopic group were significantly greater than those in open reduction group( P <0.05);intraoperative bleeding, incision length, and hospitalization days in arthroscopic group were less than those in open reduction group( P <0.05);preoperative Lysholm score in arthroscopic group and open reduction group were 49.1±2.3 and 48.9±1.1 respectively, and improved to 95.9±1.7 and 86.4±1.2 at 12 months after operation respectively( P <0.05);preoperative IKDC scores in arthroscopic group and open reduction group were 47.6±4.1 and 48.1±3.9 respectively, and improved to 96.9±1.5 and 87.1±1.4 at 12 months after operation( P <0.05)., Conclusion: Arthroscopic double posterior internal approach for acute simple posterior cruciate ligament tibial stop avulsion fracture has satisfactory early results and better efficacy than traditional open surgery, which has advantages of less trauma, faster recovery and easier operation.

Objective: To investigate the early efficacy of arthroscopic autologous osteochondral grafting in the treatment of recurrent anterior shoulder dislocation., Methods: From January 2019 to January 2021, 17 patients with recurrent anterior dislocation of shoulder who underwent arthroscopic autologous osteochondral grafting were selected, including 12 males and 5 females, ranging in age from 17 to 55 years old, with a mean of (32.88±12.33) years old. Rowes rating system for Bankart repair(Rowe), Oxford Shoulder Instability Score (OSIS) and Simple Shoulder Test (SST) were compared before operation, 6 months after operation and at the latest follow-up. OSIS and SST used to evaluate shoulder function were recorded before surgery and at the latest follow-up. The shoulder mobility and intraoperative and postoperative complications were also recorded., Results: All 17 patients were followed up, and the duration ranged from 7 to 25 months, with a mean of (18.4±5.4) months. During the follow-up period, there was no re-dislocation, no vascular or nerve injury. Rowe score increased from 26.2±6.0 before operation to 74.4±4.0 and 82.4±3.1 after 6 months and the latest follow-up. There was significant difference in Rowe score between different time points after operation and before operation ( P <0.05). The OSIS increased from 37.0±3.6 before operation to 47.4±2.6 and 52.7±2.6 after 6 months and the latest follow-up. There was significant difference in OSIS between different time points after operation and before operation ( P <0.05). The SST score increased from 6.8±0.7 before operation to 9.8±0.8, 11.6±2.6 after 6 months and the latest follow-up. There was significant difference in SST score between different time points after operation and before operation ( P <0.05). At the latest follow-up, the lateral external rotation and abduction external rotation activities of the patient were significantly improved compared with those before operation., Conclusion: This study provides preliminary evidence that arthroscopic autologous osteochondral grafting can achieve satisfactory early clinical outcomes and stability in patients with recurrent anterior shoulder dislocation with glenoid fracture and defect less than <20%, which is a reliable and effective procedure.

Recurrent anterior dislocation of shoulder with bone defect is one of the common diseases of shoulder joint. How to effectively repair glenoid bone defect and reduce recurrence rate of shoulder dislocation is a problem that clinicians focus on. Bone grafting could stimulate bone, promote bone regeneration and bone remodeling, and restore the normal anatomical structure of glenoid. Among them, Bristow-Latarjet procedure is a classic operation for recurrent shoulder dislocation. Latarjet procedure could repair larger glenoid bone defects, but with higher surgical skills for surgeons;autogenous iliac grafting is the first choice for revision once Latarjet procedure failed;osteochondral grafting (autogenous and allogenous) has certain advantages in reconstructing original articular surface and preventing joint degeneration, but autologous osteochondral grafting may cause secondary injury, while immune rejection is difficult to avoid for allogenous osteochondral grafting. With the improvement of composite materials, and the mechanism of bone regeneration and remodeling, as well as the advantages and disadvantages of bone grafting, tissue engineering technology may become an effective method for the treatment of glenoid bone defect in the future.

The surgical treatment of recurrent anterior shoulder dislocation is a difficult problem in the field of sports injury medicine. The main reason focus on dynamic and osseous constraints of shoulder joint could not recover well. At present, arthroscopic surgery is used at home and abroad, and could receive statisfied postoperative effect, but the choice of specific surgical methods is still controversial. According to presence and size of glenoid and humeral skull defects, different treatments should be selected in clinic. The author recommends that no articular glenoid defect or glenoid defect <20%, choose Bankart surgery;articular glenoid defect <20% with Hill-Sachs bone defect <40%, choose Bankart surgery combined with remplissage surgery or ASA surgery;Glenoid defect 20% to 25%, choose "Sling";Glenoid defect 25% to 40%, choose Bristow-Latarjet; Glenoid or Hill-Sachs bone defect>40% or Bristow-Latarjet if the surgical repair fails, bone grafting is used. In addition, if (humeral avulsion of glenohumeral ligaments, HAGL) injury existed, HAGL injury repair should be used. In addition to considering the important factor of bone defects, it is necessary to combine patient's age, exercise level and surgeon's technique to comprehensively select the bestsurgical method.

Shoulder arthroscopic as a conventional method usually is applied to repair rotator cuff tears. In clinical, plenty single-row, double-row and transosseous tunnels suture technique are performed, but the ideal suture technique for rotator cuff repair is not found. Compared with single-row, double-row has better strength in biomechanics property. As the two best suture technique among the single-row, massive cuff stitch and modified Mason-Allen suture have the strongest biomechanics property. Clinical trials indicate that double-row could improve healing rates, but there are no significant difference in clinical outcome functional scores. Transosseous tunnel techniques possess a better bio-mechanic property, which could improve regional micro-environment and induce tendon-bone healing. Transosseous tunnel techniques are better for small to media size rotator cuff tears and osteoporosis patient. The author suggest that optimal rotator cuff repair technique should performed according to skill of performer and individual of patient by analysing bio-mechanic properties, clinical outcome, operative complexity and patient situation. The technique should follow simple opertaion, rapid, less trauma, stable fixation and utility to perform.

Titanium alloy has good biological properties and is commonly used in orthopedics, but its bone integrity and antibacterial properties are poor, so surface modification is needed to make up for its shortcomings. Chitosan has good biocompatibility and film forming ability, and can be used as a carrier to introduce the target drug to the surface of titanium alloy, which can effectively improve the biological properties of titanium alloy materials and increase its application range. In this paper, the related research of chitosan surface modified titanium alloy materials in recent years is summarized. The modification methods of chitosan coating, the improvement of osteogenesisand antibacterial properties of titanium alloy materials are discussed in order to provide guidance for the clinical application of coating modification of titanium alloy materials.

The rate of rotator cuff injury repair and retear is high in elderly patients due to the combination of different degrees of osteoporosis. To solve this problem, many surgeons try to reduce retear rate of rotator cuff injuries in these patients by increasing the initial fixation strength of anchors and changing local bone conditions. The rapid advances of tissue engineering have made it possible to use growth factors as an aid. However, repair of rotator cuff injury with osteoporosis is still a great challenge for clinical workers. How to better increase anchor fixation strength, improve micro-environment of tendon and bone healing, reduce the rotator cuff retear rate have become the research focus in recent years. The paper reviewed literatures on the relationshipbetween osteoporosis and rotator cuff injury, effect of osteoporosis in rotator cuff tendon healing, methods of reducing osteoporosis on rotator cuff tendon healing, in order to guide clinical treatment, improve operative effect and postoperative satisfaction.

Objective: To identify risk factors for minimally invasive surfactant administration (MISA) failure in the treatment of preterm infants with respiratory distress syndrome (RDS) and the influence of MISA failure on neonatal outcome., Methods: A retrospective analysis was performed for the clinical data of 148 preterm infants with a gestational age of ≤32 weeks and a clinical diagnosis of RDS, who were admitted to the neonatal intensive care unit of eight tertiary hospitals in Beijing, Tianjin and Hebei Province from July 1, 2017 to December 31, 2018 and were treated with MISA (bovine pulmonary surfactant, PS). According to whether MISA failure (defined as the need for mechanical ventilation within 72 hours after MISA) was observed, the infants were divided into two groups: MISA failure group (n=16) and MISA success (n=132). A logistic regression analysis was used to investigate the risk factors for MISA failure and its influence on neonatal outcome., Results: The MISA failure rate was 10.8% (16/148). The logistic regression analysis showed that a high incidence rate of grade >II RDS before PS administration, low mean arterial pressure and high pulse pressure before administration, a low dose of initial PS administration, and long injection time and operation time were the risk factors for MISA failure (OR=5.983, 1.210, 1.183, 1.055, 1.036, and 1.058 respectively, P<0.05). After the control for the above risk factors, the logistic regression analysis showed that the MISA failure group had a significantly higher incidence rate of bronchopulmonary dysplasia (BPD) (OR=8.537, P<0.05)., Conclusions: A high grade of RDS, a low mean arterial pressure, and a high pulse pressure before administration are independent risk factors for MISA failure, and a low dose of initial PS administration, a long injection time, and a long operation time may increase the risk of MISA failure. MISA failure may increase the incidence rate of BPD in preterm infants.

Objective: To explore the clinical efficiency and safety of CHOP regimen containing pegylated liposomal doxorubicin (PLD) for the aged patients with advanced diffuse large B-cell lymphoma (DLBCL)., Methods: Fifty aged patients with advanced DLBCL treated in our hospital from February 2010 to February 2014 were selected and divided into two groups. Out of 50 cases, 25 cases received standard CHOP regimen (sCHOP group), other 25 cases received CHOP regimen containing PLD at dose of 30 mg/m2 (PLD+CHOP). These patients were followed up for 18 months, and the total effective rate, the survival rate and the adverse reaction rate were compared between these two groups., Results: After receiving different treatments, the survival rate of patients on 6, 12 and 18 months in PLD+CHOP group was 88.0%, 80.0% and 76.0%, respectively, and the survival rate of 18 month was significantly higher than that in the sCHOP group (P<0.05); The total effective rate in the PLD+CHOP group was statistically higher than that in the sCHOP group (P<0.05); and all the incidences of non-hematological toxicity, peripheral sensory neuropathy, lung infection, gastrointestinal reaction and hepatotoxicity were not statistically different between two groups (P>0.05), while the incidence of cardiac toxicity including acute myocardial infarction, congestive heart failure, atrioventricular block (AV block) and paroxysmal atrial tachycardia significantly decreased in the PLD+CHOP group (P<0.05)., Conclusion: The efficiency of CHOP regimen containing PLD for the aged patients with advanced DLBCL has been confirmed to be significant, and its cardiac toxicity is low, thus being worth to be popularized and applied for the treatment of advanced diffuse large B-cell lymphoma.

Parkinson disease (PD) is the second most common neurodegenerative disorder, characterized by a progressive loss of dopaminergic neurons in the substantia nigra (SN). The pathology of PD remains unclear. Recent findings suggests neuroinflammation plays a critical role in PD. Occurrence of neuroinflammation, including microglia and astrocyte activation, T lymphocyte infiltration and blood-brain barrier disruption, has been identified in PD. However, the mechanism of neuroinflammation regulation in PD is not fully deciphered. In this review, we focus on the cutting edge in researches of neuroinflammation in PD, which may provide us new ideas in prevention and recovery of PD.

Objective: To study the characteristics of R bone age, C bone age, and T bone age in children with different causes of short stature based on the Tanner and Whitehouse skeletal age assessment system 2 (TW2), and to provide a reference for the etiological diagnosis of short stature., Methods: Three hundred and sixty-three children with previously untreated short stature were classified into four groups according to the causes: growth hormone deficiency (GHD; 27 cases), idiopathic short stature (ISS; 280 cases), small for gestational age (SGA; 41 cases), and Turner syndrome (TS; 15 cases). The X-ray films of their left hand-wrist bones were taken to determine the bone age. R bone age, C bone age, and T bone age were assessed by the TW2 method and compared with their chronological age (CA)., Results: R bone age, C bone age, and T bone age were over 2 years less than CA in both boys and girls from the GHD group. In the ISS group, R bone age, C bone age, and T bone age were about 1 year less than CA in boys, while there were no significant differences between the bone ages and CA in girls. In the SGA group, there were no significant differences between the bone ages and CA in either boys or girls. In the TS group, R bone age and T bone age were significantly lower than CA, while there was no significant difference between C bone age and CA., Conclusions: The children with different causes of short stature have different characteristics of R bone age, C bone age, and T bone age assessed by the TW2 method. The assessment of R bone age, C bone age, and T bone age by the TW2 method is helpful for the etiological diagnosis of short stature in children.

Objective: To detect expression of Slit2 and Robo4 in mouse ventricular muscle blood vessel and explore the impact of exogenous Slit2 on proliferation and migrate of mouse cardiac microvascular endothelial cells., Methods: Slit2 and Robo4 expression in mouse ventricular muscle blood vessel was detected by immunohistochemistry. Slit2 and Robo4 expression in cardiac microvascular endothelial cells isolated from mouse ventricular muscle were detected by euzymelinked immunosorbent assay and immunofluorescence, respectively. The effects of various concentrations exogenous Slit2 on proliferation of mouse cardiac microvascular endothelial cells was examined by CCK-8 cell proliferation kit. Transwell chamber was used to detect migration of mouse cardiac microvascular endothelial cells treated with 800 µl M199 culture medium containing 20%FBS (negative control), 10 ng/ml VEGF(positive control), 100 ng/ml Slit2(Slit2) and 100 ng/ml Slit2+10 ng/ml VEGF (Slit2+VEGF) and incubated for 18 h at 37 °C and 5%CO(2)., Results: Both Slit2 and Robo4 protein expressions were detected in ventricular muscle blood vessel. Slit2 protein expression was detected in mouse microvascular endothelial cells. Protein and mRNA Robo4 expressions were also evidenced in mouse microvascular endothelial cells. Proliferation of mouse cardiac microvascular endothelial cells was not affected by exogenous Slit2. Migration of mouse cardiac microvascular endothelial cells was not affected by exogenous Slit2 (22.1 ± 2.8 vs. 23.2 ± 3.8 in negative control, P > 0.05) and significantly enhanced by VEGF (65.3 ± 3.8, P < 0.05 vs. Slip2 and negative control), this effect could be blocked by cotreatment with Slip2 (29.2 ± 3.4 in Slip2+VEGF, P < 0.05 vs., Vegf) Conclusion: Slit2 and Robo4 are expressed in mouse ventricular muscle blood vessels and cardiac microvascular endothelial cells. Exogenous Slit2 has no impact on the proliferation of mouse cardiac microvascular endothelial cells but could inhibit VEGF-induced mouse cardiac microvascular endothelial cell migration.

Objective: To observe whether the mutant selective windows (MSW) of ciprofloxacin would be reduced after its combination against Pseudomonas aeruginosa in rabbits., Methods: Firstly the minimal inhibitory concentration (MIC), mutant prevention concentration (MPC), mutant selective windows (MSW, MPC-MIC) and selective indices (SI, MPC/MIC) of ciprofloxacin and tobramycin were measured in vitro respectively with standard strain ATCC27853. And the MIC was detected for the combination of ciprofloxacin and tobramycin. The rabbit tissue cage model was constructed to determine the pharmacokinetic parameters of ciprofloxacin by HPLC (high performance liquid chromatography). Fifty-five rabbits were randomly divided by a random number table into 11 groups: physiological saline in 1 group, ciprofloxacin alone in 5 groups and ciprofloxacin plus tobramycin in another 5 groups. The rabbits received ciprofloxacin 10 times a day at a 2-hour dosing interval. In 2 dosing groups, the steady state concentrations of ciprofloxacin reached to 0.25, 0.5, 1.0, 2.0 and 4.0 mg/L respectively. The dose of tobramycin was 2.0 mg×kg(-1)×d(-1) and its peak concentration reached around 2.0 mg/L. At Day 3, the tissue juice was extracted, diluted and coated on agar plates with ciprofloxacin at a concentration of 0.25 mg/L so as to observe the growing condition of mutants., Results: Against Pseudomonas aeruginosa, the values of MIC, MPC and SI of ciprofloxacin were 0.25 mg/L, 4.0 mg/L and 16 while 0.25 mg/L, 8.0 mg/L and 32 for tobramycin respectively. Single groups: the mutants were found in 0.25, 0.5, 1.0 and 2.0 mg/L groups, but none in 4.0 mg/L group. The MPC of ciprofloxacin was the same for in vivo and in vitro. Both were at 16. Combination groups: the mutants were only found in the group with a concentration of ciprofloxacin at 0.25 mg/L while no mutants in the other groups. And MPC was 0.5 mg/L and MIC 0.125 mg/L for ciprofloxacin plus tobramycin. And the value of SI was 4., Conclusion: The combined use of ciprofloxacin and tobramycin may reduce the mutant selective windows of ciprofloxacin against P. aeruginosa in rabbits so as to reduce the occurrence of mutants to control its drug resistance.

Objective: To investigate and search correlative proteins of keloid by comparing the results of differential proteomic analysis between keloid and normal skin., Methods: From January 2010 to June 2010 two-dimensional gel electrophoresis was used to define patterns of protein expression in keloid skin from 8 patients and matched normal skin from 3 patients. Differential expression protein spots were showed and analyzed by matrix-assisted laser desorption ionization-time of flying/time of flying (MALDI-TOF/TOF) mass spectrometry., Results: This study succeeded to provide a two-dimensional protein profiling comparison between normal skin and keloid. Gel-analysis software identified an average of 2978 spots in keloid while 3053 spots in normal skin and statistical filtering yielded 40 spots of a 4-fold change, 32 of which were identified by using mass spectrometry, 20 were up-regulated and 12 were down-regulated. Functional analysis revealed that these proteins could be fractionated to carrier proteins (3 proteins), signal transduction proteins (4 proteins), proliferation and apoptosis related proteins (2 proteins), cytoskeleton proteins (6 proteins), extracellular matrix proteins (8 proteins), immunity related proteins (3 proteins), tumor related proteins (2 proteins), and function unknown protein (4 proteins)., Conclusions: Proteomic analysis can identify the proteins with variance of keloid versus normal skin. The further research to these differential proteins may help reveal the pathogenesis of keloid and provide new treatments for keloid.

Near infrared spectra of 99 lamb meat samples from three pasturing areas and two farming areas of China were scanned and analyzed to seek a cheap, rapid and effective method for lamb meat origin traceability. Two chemometric methods including linear discriminant analysis based on principal component analysis (PCA+LDA) and partial least squares discriminant analysis (PLS-DA) were used to develop the discriminate models. It was showed that there were significantly differences among the lamb meat samples from five regions based on NIR spectra after second derivative (Savitzky-Golay, 9 point) and multiplicative scattering correction (MSC) transformation in the whole wavelength. The discrimination of two models was best for classification of pasturing area and farming area, with both correctly classified by 100%. The correct classification rate of samples from five different regions using PCA+LDA model was 91.2%, higher than using PLS-DA model (76.7%). These results demonstrate that near infrared reflectance spectroscopy (NIRS) combined with chemometric analysis can be used as an effective method to classify lamb meat according to its geographical origin.

Objective: To establish a method for the expression of glycogen synthase kinase 3β with high purity and biological activity., Methods: E.coli expression system and baculovirus-insect cell expression system were used to produce the kinase, followed by purification using His-tag and GST-tag and determination of its purity and activity by SDS-PAGE and kinase reaction, respectively., Results: Glycogen synthase kinase 3β produced from E.coli represented 54% of the total bacterial protein, as compared with 96% of the total protein from the insect cell system .Glycogen synthase kinase 3β produced from insect cell exhibited an one-fold higher biological activity than the protein obtained from E.coli., Conclusions: Compared with the protein from E.coli system, glycogen synthase kinase 3β from the insect cell expression system is endowed with a higher purity and bioactivity.

Objective: To compare the therapeutic effect of impacted high tibial osteotomy and conventional high tibial osteotomy for the treatment of flexional medial osteoarthritis of knee joint in aged patients., Methods: From July 2003 to July 2006, 30 patients with flexional medial knee osteoarthritis were treated with impacted high tibial osteotomy or conventional high tibial osteotomy randomly. All patients,aged from 60 to 82 years,were suffered from 7 degrees to 19 degrees knee flexion deformities and 3 to 20 years medical histories. The bone healing periods, the recover of flexion and inversion deformities, and the recover of the knee joint function were observed postoperatively. The patients were followed up at 4, 6, 8, 9, 10, 12 and 16 weeks, and 5, 7, 9 and 12 months postoperatively. The bone healing periods and the recover of flexional and inversion deformities were evaluated and compared. Twelve months postoperatively,the knee joint function were assessed with the Lysholm scoring criteria, and the therapeutic effects were compared between the two groups., Results: There was a significant difference in the average bone healing period between the impacted high tibial osteotomy group (9.26 +/- 2.23) weeks and the conventional high tibial osteotomy group (11.53 +/- 3.15) weeks. The knee joint function were evaluated according to the Lysholm clinical rating scales. One year postoperatively,the average Lysholm score were (88.5 +/- 4.4) points in the impacted high tibial osteotomy group,and the results showed excellent in 14 cases, good in 1. The average Lysholm score were (78.1 +/- 5.7) points in the conventional high tibial osteotomy group. The results showed 8 cases excellent, 5 good, 2 fair, accordingly. Postoperatively, the flexion deformities of the knee in the impacted high tibial osteotomy group were -1.1 degrees to 0 degrees and was corrected averagely (130 +/- 3.30) after surgery, and that in conventional high tibial osteotomy group (140 +/- 3.30) (the same as preoperation). The average postoperative femorotibial angle (FTA) were 170.2 degrees (ranged from 169.1 degrees to 172.3 degrees) and was corrected 12.3 degrees to 12.5 degrees after surgery in both groups., Conclusion: Compared with conventional high tibial osteotomy, impacted high tibial osteotomy can significantly shorten the bone healing period, improve the knee flexion, varus deformity, and the knee function.

Objective: To search for differentially expressed proteins in the serum of patients with Crohn's disease., Methods: Serum protein samples obtained from 4 patients with Crohn's disease and 4 normal adults were cross-labeled with different CyDyes and underwent two-dimensional differential in-gel electrophoresis (2-D DIGE) and imaging analysis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used to identify the differentially expressed proteins., Results: 2-D DIGE revealed that the protein on spot 973 was overexpressed by 2.55 folds in the serum of patients with Crohn's disease compared with that in normal adults (P<0.05). The protein was identified as CD45 using mass spectrometry., Conclusion: CD45 overexpression in the serum of patients with Crohn's disease may play a role in the disequilibrium of the immune system.