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The crosstalk between macrophages and tubular epithelial cells (TECs) actively regulates the progression of renal fibrosis. In the present study, we revealed the significance of circular RNA ACTR2 (circACTR2) in regulating macrophage inflammation, epithelial-mesenchymal transition (EMT) of TECs, and the development of renal fibrosis. Our results showed UUO-induced renal fibrosis was associated with increased inflammation and EMT, hypertrophy of contralateral kidney, up-regulations of circACTR2 and NLRP3, and the down-regulation of miR-561. CircACTR2 sufficiently and essentially promoted the activation of NLRP3 inflammasome, pyroptosis, and inflammation in macrophages, and through paracrine effect, stimulated EMT and fibrosis of TECs. Mechanistically, circACTR2 sponged miR-561 and up-regulated NLRP3 expression level to induce the secretion of IL-1β. In TECs, IL-1β induced renal fibrosis via up-regulating fascin-1. Knocking down circACTR2 or elevating miR-561 potently alleviated renal fibrosis in vivo. In summary, circACTR2, by sponging miR-561, activated NLRP3 inflammasome, promoted macrophage inflammation, and stimulated macrophage-induced EMT and fibrosis of TECs. Knocking down circACTR2 and overexpressing miR-561 may, thus, benefit the treatment of renal fibrosis.

Macrophages, associated with their heterogenous and dynamic polarization status, actively shape the development of renal fibrosis (RF). In this study, we revealed the significance of a signalling axis, circular RNA ACTR2 (circACTR2)/miR-200c/Yes-associated protein (YAP), in regulating macrophage polarization and the development of RF. A unilateral urethral obstruction (UUO)-induced RF model was established in vivo. In vitro, interferon-γ (IFNγ) and interleukin (IL)-4 were applied to induce M1 and M2 polarization, respectively. The abundance of M1 and M2 macrophages were examined by immunofluorescence (IF) or flow cytrometry on markers specific for each subtype. Expressions of circACTR2, miR-200c and YAP were measured by quantitative real-time-polymerase chain reaction and/or Western blotting. Interactions between circACTR2, miR-200c and YAP were examined by combining luciferase assay, RNA immunoprecipitation and IF. Impact of targeting circACTR2 on RF and macrophage polarization was also examined in vivo. UUO-induced RF was associated with increased M1 and M2 macrophages, up-regulations of circACTR2 and YAP and the down-regulation of miR-200c in the obstructed kidney. circACTR2 was essential for IL-4-induced M2 polarization, but not IFNγ-induced M1 polarization. This activity of circACTR2 was mediated by sponging miR-200c and activating the downstream YAP signalling. In vivo, knocking down circACTR2 boosted miR-200c expression, reduced YAP level, lowered M2 macrophages in obstructed kidney and ameliorated UUO-induced RF. circACTR2, by targeting and sponging miR-200c, activates YAP signalling, stimulates M2 macrophage polarization and promotes the development of RF. Therefore, targeting circACTR2 may benefit the treatment of RF.

Using a melt-mixing technique, ethylene–vinyl acetate (EVA) copolymers based composites containing Multi-Wall Carbon nanotubes (MWCNTs), aluminum trihydrate (ATH), zinc borate (ZB), and gadolinium oxide (Gd2O3) were fabricated. Then, the as-prepared samples were irradiated with an electron beam (EB) at the dose range varied from 0 to 275 kGy. Moreover, we investigated the properties of irradiated and unirradiated samples. Morphological observation showed good dispersion of MWCNTs and other additives in EVA. Furthermore, the gel content, mechanical properties, the limit oxygen index (LOI) values of irradiated composites increased to 28.4% after 250 kGy after irradiated. All the conclusions indicated that the comprehensive properties of the WMCNTs/EVA composites were improved by using high energy electron beam irradiation.

Background Expensive cost of surgery has limited the use of surgical robot in China. The emergence of “Micro Hand S” surgical robot provides more choices for surgical treatment. Our study was to evaluate the safety and feasibility of “Micro Hand S” surgical robotic gastrectomy for gastric cancer. Methods Perioperative data of 75 patients who underwent “Micro Hand S” surgical robotic gastrectomy (RG) or laparoscopic gastrectomy (LG) at the Department of General Surgery, Third Xiangya Hospital, Central South University from June 2017 to January 2019 were collected to compare the short-term outcomes between the two groups. Results No statistically significant difference was found in baseline characteristics between the two groups (P > 0.05). RG group had longer operation time (P < 0.01). The harvested lymph nodes were comparable between the two groups (P = 0.084). There were five positive margins in the LG group, and the R0 resection rate was comparable between the two groups (P = 0.247). 16 complications occurred in the RG group according to the Clavien-Dindo classification system, 6 in grade I, and 10 in grade II. 68 complications happened in the LG group, 22 in grade I, 44 in grade II, 1 in grade IIIa and 1 in grade IVa. The comprehensive complications index (CCI) was similar between the two groups (P = 0.895). Intraoperative blood loss, surgical resection, reconstruction of the digestive tract intraoperative blood transfusion, Chemoradiotherapy, pathological type, degree of differentiation, proximal resection margin, time of first flatus, time of liquid diet, time of abdominal drainage tube extraction, and hospital stay for RG and LG were similar too (P > 0.05). Conclusion “Micro Hand S” surgical robotic gastrectomy is safe and feasible. Keywords Surgical robot; Gastric cancer; Gastrectomy; Safety; Feasibility

This paper presents results from numerical studies on the effect of critical factors governing the axial compression mechanical properties on square cross-section concrete-encased concrete filled steel tubular (CFST) stub columns after fire exposure. A validated three dimensional finite element model is applied for evaluating axial compression mechanical properties of concrete-encased CFST stub columns after fire exposure under different factors. The factors varied in the parametric study include fire exposure time, steel tube area ratio, longitudinal bar ratio, compressive strength of concrete, yield strength of steel tube, and sectional core area ratio. Results from parametric studies show that axial compressive strength and axial stiffness of square concrete-encased CFST stub columns after fire decrease significantly. The decline of axial stiffness is higher than that of axial compression ultimate bearing capacity. Fire exposure time and sectional core area ratio have significant influence on the reduced level of axial compressive strength and axial stiffness of square concrete-encased CFST stub columns after fire exposure. Steel tube area ratio and reinforcement ratio have some influence on the reduced level. Compressive strength of concrete and yield strength of steel tube have limited influence on the reduced level.

According to the requirements for neutron shielding and flame retardant properties of some nuclear devices, a new kind of polymer composite materials based on ethylene and vinyl acetate (EVA) polymer have been studied. EVA is the copolymer of ethylene and vinyl acetate, It can be used as materials for applications due to its flexibility, good processability, and low cost. Insulating EVA can be used for cable sheath, automotive sound damping and many other appication. Boron nitride (BN), zinc borate (ZB), magnesium hydroxide (MH) and EVA consisted the compounds with the properties of neutron shielding and flame retardant. With increasing of the contents of BN and ZB, the neutron shielding performance of materials increased up to 33.08%. With the increasing contents of MH and ZB as flame retardant, oxygen index of material have been improved. The elongation at break and tensile strength of material decreased with the increasing of filler powders. Sheet E was chosen and modified by electron beam accelerator in different doses. After modification by electron beam irradiation the sheets showed varying degrees of transformation in the OI, neutron shielding rate and mechanical properties.

A signal acquisition system for the number of projectiles in the fire control system based on Proteus’s AT89C51 single-chip microcomputer is proposed. Take 89C51 microcontroller as the control core, Tested and analyzed the projectile signal of a tank gun with its rich peripheral interface and I/O resources. Then, the amount of initial velocity reduction is determined according to the number of projectiles of each type of artillery. The system has completed the collection, storage and calculation of a certain type of tank gun projectile signal, and has an interface for communication with the host computer. It can complete the information transmission with the fire control computer, and has the advantages of small size, simple structure and easy implementation. It has certain application value for the automatic correction of the initial velocity reduction of tank guns. It also provides some reference for the system design of the military department.

Flame-retardant neutron shielding materials were synthesized based on ethylene-vinyl acetate (EVA) copolymer and with multi-walled carbon nanotubes (CNTs), boron carbide (B4C), zinc borate (ZB) as fillers. With the increase of filler content, the tensile strength of the composite increased primarily and then decreased, and the elongation at break continued to decrease. CNTs and ZB formed a synergistic flame-retardant system. The surface-modified CNTs improved the mechanical properties, thermodynamic properties, and flame retardancy of the composites. With the increase of the CNTs content, the flame-retardant properties of composites increased first and then remained stable. Electron beam (EB) radiation changed the mechanical properties, flame retardant properties and thermodynamic properties of the composites. Taking an Am–Be neutron source as the radiation source, the thermal neutron transmittance of 2 mm sample was 50.72%.

The tank gun is the main battle weapon of the tank. It is mainly used to destroy and suppress enemy tank armoured vehicles, eliminate living forces and destroy fortifications. However, after repeated use of artillery for a long time, projectile muzzle velocity and maximum pressure will decrease. Shortening distances and increasing the area of projectiles will greatly affect the ability of artillery to carry out combat missions. Taking the gun barrel as the main research object, the main factors that cause the muzzle velocity of the artillery muzzle projectile to be reduced are analyzed. The mechanism of the muzzle velocity is analyzed, and the method for calculating the muzzle velocity decrease is explored, which is of great significance for improving the accuracy of artillery firing. It also provides reference for estimating the life of gun barrels.

This study firstly investigated the feasibility effect and safety of Ganoderma Lucidum Spore Powder (GLSP) for treating patients with epilepsy.Eighteen eligible patients with epilepsy were included. They all received GLSP treatment for a total of 8 weeks. The primary outcome included weekly seizure frequency. The secondary outcomes consisted of each seizure episode, and quality of life, measured by the Quality of Life in Epilepsy Inventory-31 (QOLIE-31), as well as the adverse events (AEs).After treatment, GLSP can significant reduce the weekly seizure frequency, compared with it before the treatment (P = .04). However, GLSP did not exert promising effect in each seizure episode (P = .13), and quality of life, measured by the QOLIE-31 scale (P = .11). Additionally, only minor AEs occurred during the treatment period.The results of this study showed that GLSP may be effective for reducing the weekly seizure frequency. Further studies are still needed to warrant this result.

Background The increasing epidemic of fine particulate matter (PM2.5) is a serious threat to human health. It induces the occurrence of liver fibrosis, but its molecular mechanism is not yet clear. The molecular mechanisms of PM2.5 inducing liver fibrosis were investigated in this study. Methods The cell viability of LX-2 cells and primary hepatic stellate cells (HSCs) was detected using 3-(4,5-dimethylthiazol-2-yl)−2,5-diphenyltetrazolium bromide (MTT) assay. In vitro enzyme-linked immune sorbent assay (ELISA) kits were used to detect the concentrations of antioxidant enzymes and reactive oxygen species (ROS). The mitochondrial transmembrane potential (MTP) was determined by JC-1 dye. Knockdown of Parkin was carried out by Parkin-specific siRNA transfection. Relative mRNA and protein expressions were evaluated by qRT-PCR, Western blotting, and immunofluorescence analysis. Results PM2.5 activated LX-2 cells and primary HSCs, inducing the liver fibrosis along with down-regulation of the gelatinases MMP-2, and up-regulation of myofibroblast markers collagen type I and α-SMA. The levels of ROS and reactive nitrogen species (RNS), as well as the lipid peroxidation marker malondialdehyde (MDA) were significantly up-regulated in LX-2 cells and primary HSCs treated with PM2.5. Also, the enzymatic antioxidants levels were disturbed by PM2.5. Furthermore, PM2.5 decreased the MTP, releasing cytochrome c from the mitochondria to the cytosol. The dynamics of mitochondria were regulated by PM2.5 via facilitating mitochondrial fission. The excess ROS induced by PM2.5 triggered the mitophagy by activating PINK1/Parkin pathway, and inhibition of mitophagy induced by PM2.5 diminished the liver fibrosis. Conclusion PM2.5 may induce mitophagy via activating PINK1/Parking signal pathway by increasing ROS, thereby activating HSCs and causing liver fibrosis.

Thinning features of 22MnB5 in hot forming process were investigated by simulation of AUTO-FORM on the base of verification of the results in a published paper. The thinning of 22MnB5 in the isothermal forming process was calculated and the effect of temperature on cracking was evaluated. A mathematics model of forming limit, which is called FLE (Forming Limit Equation), is recommended to predict the cracking of the sheet in the hot forming process in stead of FLD (Forming Limit Diagram). And effect of other parameters, i.e. blank holding force, friction coefficient, thickness of sheet and strain rate, was also investigated.

With the development of modern science and technology and the transformation of traditional disciplines, interdisciplinary development is the main trend of science in the world now. The multidisciplinary crossing has become the power to promote the development of discipline. The development of multidisciplinary crossing specialty and interdisciplinary education has increasingly become the urgent request of institutions of colleges. Biomedical engineering specialty is a multidisciplinary specialty, which need to renew educational ideas, integration of resources, improve the management mechanism and solve the problems of the disciplines development and curriculum construction.

For a long time, training work of army equipment maintenance crew mostly goes on real-equipment, which is organized by academies or relevant units later. In some extent, this kind of conventional maintenance ways decrease the efficiency and quality of weapon equipment maintenance. In face of more and more new equipment, it not only increases the difficulty of maintenance training but also brings a new challenge to conventional maintenance ways. Aiming at the lack of maintenance training ways of conventional land-battle equipment, we adopt new technology of virtual reality in recent years to create typical-type amphibious assault vehicle virtual maintenance training system, which provide new means for maintenance crew. This text is tend to analyze interactive desktop virtual maintenance training system, and then for instance, briefly introduce typical-type amphibious assault vehicle.

A novel operation mode is proposed to enhance the photovoltaic performance of dye-sensitized solar cell (DSSC) by applying an external bias on the back electrode. The measured data shows that the photovoltaic conversion efficiency and open circuit voltage of DSSC are significantly improved by more than 38.8% and 5.8% under the stimulated AM 1.5 sunlight by using the biased operation mode compared to the conventional operation mode without an external bias applied. The improved photovoltaic performance could be attributed to the suppressed back reaction from the recombination between the photoelectrons produced from dyes and the I3- ions in electrolyte under the novel operation mode.

HfAlOx based RRAM devices were fabricated using atomic layer deposition by modulating deposition cycles for HfO2 and Al2O3. The effect of rapid thermal annealing (RTA) on the resistive switching uniformity of HfAlOx based RRAM devices was investigated. Compared to the as-deposited devices, the resistive switching uniformity of HfAlOx based RRAM devices after RTA treatment are remarkably improved. The uniformity improvement of HfAlOx based RRAM after RTA treatment is related to microstructure change in the resistive switching film.

To acquire the dynamic characteristics of electrical control component under tank gun firing impact, the author simplified tank structure, combined the three-dimensional modeling software Solidworks and dynamics simulation software ADAMS, constructed a full vehicle dynamics simulation model of a main battle tank and simulated the firing of tank gun. The compare between experimental and simulated results proved the validity and reliability of this model. This set the foundation for the analysis of fault principles of fire control computer and its internal structure under the impact of tank gun firing.

This paper presents a review of research progress in fire performance of concrete-filled steel tubular (CFST) columns. Experimental results of CFST columns in fire are reviewed with influence parameters, such as heights, cross-sectional dimension, section types, concrete types, concrete strengths, load ratio, load eccentricity, fire exposed sides and so on. Some conclusions of CFST columns under fire conditions are summarized. Deficiencies in the fire performance experiments of CFST columns are identified, which provide the focus for future research in the field.

Fire safety is one of the most important performances index to evaluate building structures. The property of building members after exposure to fire involved with the safety of buildings after fire, and it will be necessary to estimate the post-fire residual strength of the structure in order to decide the appropriate strategy for repair. This paper summarizes the research progress of concrete-filled steel tubular (CFST) columns. Basic mechanical properties of conventional CFST columns after exposure to fire, CFST columns after the whole fire exposure process under sustained axial load, and CFST columns with special forms after exposure to fire are discussed.

To investigate the changes of corneal tissues morphological structure and biomechanical properties in different month age rabbits, the eyeballs of the 1 month, 2 month and 3 month-old-New Zealand white rabbits were obtained and getting the cornea tissues, and then measured the thickness of the cornea tissues. The first part of the corneal tissue was used to observe cornea structure with HE staining. The second part was used to observe collagen fibrils by electron microscope. The third part of the cornea tissues were cut into strips and used to test the elastic modulus of the cornea on Instron5544 tester. The thickness of the cornea was increased with month age. HE staining observation shows that the numbers of corneal fibroblasts were decreased and the fiber bundle increased with month age. Electron microscope observation shows that the diameters of collagen fibrils were increased at 2 and 3 month. Biomechanical experiment results reveal that cornea tissues elastic modulus was increased with month age. In the post-embryonic stages, the structure of cornea, the structure and number of collagen fiber, the number of corneal fibroblasts and the biomechanical properties of cornea were changed continually.

The temperature distribution of concrete filled steel tube reinforced concrete (CFSTRC) square short columns was analyzed. Test results of four CFSTRC square short columns were reported in this paper. The specimens exposed to the ISO-834 standard fire without initial loads. The fire test lasted 180 minutes. The influential factors included the side length of cross-section, slenderness ratio and steel tube area ratio. Finite element method (FEM) simulation was used to calculate temperature distribution of CFSTRC square short columns at elevated temperature. The test results show that the larger side length of cross-section, the lower temperature inside the specimens with the same fire exposure time and steel tube area ratio and height of specimens. Under the same fire exposure time and side length of cross- section and steel tube area ratio, the slenderness ratio was larger, and the temperature inside the specimens was lower. With the same fire exposure time and side length of cross-section and slenderness ratio, the steel tube area ratio had slight influence on temperature distribution inside the specimens. The FEM simulation results agreed well with the experimental results. The FEM simulation was capable of calculating temperature distribution of CFSTRC square short columns with an accuracy that was sufficient for design purposes.

To understand the effect of mechanical stimulation on posterior sclera reinforcement (PSR), the rabbit scleral fibroblasts after PSR were subjected to stretch in vitro and MMP-2 and TIMP-2 expression of scleral fibroblasts were evaluated. Three-week-old rabbits were monocularly performed by eyelid suturation randomly to prepare experimental myopia eye. After 60 days, the experimental myopia eyes were treated by PSR. After 6 months, the posterior pole scleral fibroblasts (normal sclera - group A, sclera after operation - group B and fusion region of sclera and reinforcing band group C) were isolated and cultured in vitro. The cells were subjected to cyclic stretch regimens (sine wave, 3% and 6% elongation amplitude, 0.1Hz, 48h duration) by FX-4000 Tension System. The MMP-2 and TIMP-2 expression of scleral fibroblasts were evaluated by ELISA method. The results show that after cyclic stretch to the scleral fibroblasts of the normal sclera and the sclera after operation, the MMP-2 expression was significantly reduced and the TIMP-2 expression was significantly increased, the MMP-2 and TIMP-2 expression of the scleral fibroblasts of the fusion region after operation was no changed. It was indicated that the mechanical stimulation could regulate the MMP-2 and TIMP-2 expression of scleral fibroblasts and play an important role in the process of treating high myopia with PSR surgery.

Biotechnology specialty is a multidisciplinary and experimental specialty. With the development of modern science and technology and the transformation of traditional disciplines, interdisciplinary development is the main trend of science in the world now. The multidisciplinary crossing has become the power to promote the development of discipline. The development of multidisciplinary crossing specialty and interdisciplinary biotechnology education has increasingly become the urgent request of institutions of medical colleges and universities. The biotechnology education need to renew educational ideas, integration of resources, improve the management mechanism and solve the problems of the disciplines development and the theory and experiment curriculum construction and teacher team construction.

Background Previous studies have reported that spore powder of Ganoderma lucidum (SPGL) may be effective for the treatment of Alzheimer's disease (AD). However, its efficacy is still inconclusive. Thus, this systematic review will aim to assess its efficacy and safety for AD. Methods We will search the electronic databases of Cochrane Central Register of Controlled Trials, EMBASE, MEDILINE, the Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, and Chinese Biomedical Literature Database to assess the efficacy and safety of SPGL for patients with AD from their inceptions to the present. All case-control studies and randomized controlled trials will be considered for inclusion in this study. Two review authors will independently perform the study selection, data extraction, and risk of bias evaluation. Results The primary outcome includes the cognitive status for patients. The secondary outcomes consist of the quality of life, AD symptoms, and adverse events. Conclusions This systematic review will present the existing evidence for the efficacy and safety of SPGL for treating patients with AD. Dissemination and ethics The results of this systematic review will be disseminated by through peer-reviewed journals. It does not needs ethic approval, because it does not involve individual patient data. Systematic review registration PROSPERO CRD42019119426.

The mechanical stimulation can affect the biological function of lung cells, but little is known about the effects on biomechanical properties of lung fibroblasts. In this paper, the human lung fibroblasts (MRC-5) were subjected to cyclic stretch (5% and 10% elongation amplitude) by FX-4000 Tension System. The micropipette aspiration technique was used to investigate the viscoelasticity of MRC-5. The results: for 5% stretch group, the viscoelastic parameters of MRC-5 were significantly lower than static group at 72 h; for 10% stretch group, the viscoelastic parameters of MRC-5 were significantly lower than static group at 48 h and 72 h, there was no difference of the viscoelastic parameters between 48 h and 72 h. The changes of viscoelasticity suggest that the lung fibroblast have different response to different mechanical stimulation and the mechanical stimulation plays an important role in regulating the viscoelasticity in the process of the growth and development.

The auto-loader is the core part and the key technique in the weapon system of tank.This paper mainly introduces and discusses the structural principle and the failure causes of auto-loader,using PLC reforms the hardware circuit of auto-loader simulator,besides setts common faults in the auto-loader simulator,finally the teacher checks the ability of the student through the touch screen.It is feasible on the result of the technique emulation and supports the maintenance training of auto-loader.

Shear strength and stiffness of fire-damaged reinforced concrete (RC) beams were researched. The nonlinear finite element method (FEM) was developed to simulate shear strength of fire-damaged RC beams. Considering mechanical properties deterioration of concrete and steel reinforcing bar, the parameters of fire-damaged RC beams, including fire exposure time, shear span to depth ratios, concrete strength, diameters of stirrups and spacing of stirrups, were analyzed. Based on numerical analysis, the change of shear strength and stiffness of fire-damaged RC beams were identified. The results showed that shear strength and stiffness of fire-damaged RC beams changed under different parameters. With increase of fire exposure time or increase of shear span to depth ratio or decrease of concrete strength, shear strength and stiffness of fire-damaged RC beams descended obviously. With decrease of diameters of stirrups or increase of spacing of stirrups, shear strength of fire-damaged RC beams descended gradually, but stiffness of fire-damaged RC beams had little change.

The fire protection method of steel space truss structures was researched. Fire protection methods of steel structures were listed. For steel space truss structures, the advantages and disadvantages of fire protection methods were introduced. The screen method was suitable for fire protection of steel space truss structures. One project of fire protection of steel space truss structure was shown as an example. The process of screen method was provided for fire protection of steel space truss structures. According to this project, the technology of fire protection of steel space truss structures was enriched. The research results could help to deal with fire protection of steel space truss structures.

In order to research the calculating method of flexural strength of fire-damaged reinforced concrete (RC) beams with carbon fiber reinforced polymer (CFRP) sheets strengthening, the flexural strength of fire-damaged beam was analyzed with section analysis. The fire exposed region includes tensile region and compressive region. A procedure was developed for quantifying the amount of bending moment of fire-damaged RC beams section with an external strengthening CFRP sheets. An equation of CFRP sheets of effective strain was recommended. The proposed method was verified under the experimental results as well. The results show that the proposed approach is capable of predicting bending moment of fire- damaged RC beams with an accuracy that is sufficient for design purposes.

In order to research the calculation method of shear capacity for fire-damaged reinforced concrete (RC) beams, the reason of drop of shear capacity was analyzed from material properties and transfer mechanisms of RC beams after fire. Formulas of shear capacity were suggested for fire-damaged RC beams. Based on test analysis, the values of reduction factors of shear capacity were proposed under concentrated load. The results show that suggested calculation method is capable of predicting shear capacity of fire-damaged RC beams exactly. The values of reduction factors of shear capacity need further experiments research.

The assessment method of fire-damaged concrete bridge with prestressed hollow core plate girders was presented in this paper. The historical sketch of assessment of fire-damaged concrete structures was briefly introduced. One fire-damaged concrete bridge with prestressed hollow core plate girders was shown as an example. The process of assessment of fire-damaged concrete bridge with prestressed hollow core plate girders was provided. According to the assessment results, methods of repair and strengthening were presented for different fire-damaged level of prestressed hollow core plate girders. The research results could help expand use of fire-damaged assessment and repair of prestressed concrete bridges.

The springback of 22MnB5 steel in hot forming was investigated using simulation of AUTO-FORM, and a mechanics model is presented to analysis spring-back. The results show that temperature is key parameter to affect the springback of 22MnB5 steel in hot forming. Raising temperature is effective method controlled the springback in hot forming of 22MnB5 steel. When temperature is below 300℃, the thickness of sheet has influence on the springback. While temperature is over 500℃, the effect of the thickness of the sheet on springback is not significant. Blank holder force, friction coefficient, punch radius, strain rate have little effect on the springback in sheet metal forming for 22MnB5 steel.

We conducted a comparative analysis of the first domestically produced Chinese surgical robot, 'MicroHand', laparoscopic, and barehanded approaches in tying surgical knots.Four surgeons performed square or triple knots individually using the three approaches and documented the operational time, circumference, the bearable tension and action trajectory for each knot.MicroHand took more time than the barehanded method but nearly the same as with the laparoscope. The barehanded method generated the smallest knots among the three approaches and MicroHand produced smaller square knots than those by laparoscope. MicroHand and barehanded methods produced square knots displaying higher bearable tension than those produced by the laparoscope. For the action trajectory, MicroHand operated in a smaller space than that needed by the laparoscope.The square knots produced by MicroHand were tighter and more solid than those by laparoscope, although the triple knots generated by the two methods were similar. Also MicroHand required a smaller operational space than the laparoscope.

The special-shaped concrete-filled steel tubular column (SCFST column) is recognized to have high bearing capacity and good fire resistance. This paper introduced a nonlinear FEA approach to analysis the temperature field of SCFST under standard ISO-834 fire condition. Finite element model was built with nonlinear material properties elements in ANSYS; thermal boundary conditions were applied to the model with convection and radiation combined to simulate the fire condition, and several conclusion were obtained from the nonlinear FEA results.

Environmental property of Polybromodiphenyl Ether and how it is restricted by Convention of Stockholm is introduced. Through the analysis of manufacture, application, current technique and substitution situation of Polybromodiphenyl Ether, the main problem of Polybromodiphenyl Ether Fire Retardant is pointed out, and suggestions of improvement is given in this paper.

Aming at some shortcomings of maintenance training on actual equipments, it developed half-practicality maintenance training system based on bus-mastering. Among the system, hardware sub-system and control software sub-system design and development of the master platform are key. Basic functions demand was analyzed, on the basis of which main technology indexes was designed. Control software sub-system was designed to include such four parts as control and demonstration, training check and evaluation, comprehensive training, signal flow control and display. Process design of each module of the four parts was implemented. This is significant to innovating equipments maintenance training manners and methods based on virtual reality and bus-mastering technology, and is significant to improving training effectiveness.

With the development and application of all kinds of newest technologies, current weapon equipments are generally complicated integrative systems with mechanical, electrical and liquid su-systems. This makes maintenance training manner and methods be serious problem. So, half-practicality maintenance training system based on bus-mastering will be developed. Complete scheme and overall arrangement were designed based on research about functions of the maintenance training system. It deeply analyzed the need of hardware sub-system and software sub-system of the maintenance training system, on the basis of which one actual equipment system was reconstructed and hardware and software were designed. Reconstruction is mainly used to set faults. It provides guidance to developing half-practicality maintenance training system based on bus-mastering.

Experiments of seven two-span reinforced concrete (RC) T-beams were introduced. One T-beam was normal temperature control T-beam, and the other six T-beams were heated under ISO-834 standard fire. All T-beams had the same geometrical dimensions and reinforcement as well as the loading and support arrangement. The fire-damaged T-beams were classified into two groups according to the fire exposure time. Different fire exposure time including 60 minutes and 75 minutes were investigated. In each group, one T-beam was unstrengthened control T-beam, and the other two T-beams were strengthened with carbon fiber reinforced polymer (CFRP) sheets. The results showed the way of moment redistribution of T-beam changed greatly because of the influence of fire. Different from the normal temperature T-beam, the fire-damaged T-beams had obvious moment redistribution at the beginning of the loading because of the variable stiffness along the length of the T-beams. The stiffness equivalency method for evaluating the moment distribution of RC continuous beams after fire exposure is presented. The scope of application for proposed method is between concrete cracking and yield load. The proposed method is based on the principle of equivalent stiffness. Considering the reduced elastic modulus of concrete and steel bars for fire exposure, a procedure was developed for quantifying the amount of sagging moment and hogging moment that can occur in fire-damaged continuous beams with an external CFRP sheets strengthening or without. The proposed method was verified under the experimental results as well. The proposed stiffness equivalent approach is capable of predicting bending moment of fire-damaged RC continuous T-beams with an accuracy that is sufficient for design purposes.