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After harvesting multiple costal cartilages, the local defect disrupts the integrity of the chest wall and may lead to obvious thoracic complications, such as local depression and asymmetry of the bilateral thoracic height. Decellularized materials have been used for tissue reconstruction in clinical surgeries. To apply xenogenic decellularized cartilage in costal cartilage defects, porcine-derived auricular and costal cartilage was tested for characterization, cytotoxicity, macrophage response, and tissue regeneration. Most of the DNA and α-Gal were effectively removed, and the collagen was well preserved after the decellularization process. The glycosaminoglycan (GAG) content decreased significantly compared to that in untreated cartilage. The decellularized auricular cartilage had a larger pore size, more pores, and a higher degradation rate than the decellularized costal cartilage. No apparent nuclei or structural damage was observed in the extracellular matrix. The decellularized auricular cartilage had a higher cell proliferation rate and more prominent immunomodulatory effect than the other groups. Two types of decellularized cartilage, particularly decellularized auricular cartilage, promoted the tissue regeneration in the cartilage defect area, combined with noticeable cartilage morphology and increased chondrogenic gene expression. In our research, the functional components and structure of the extracellular matrix were well preserved after the decellularization process. The decellularized cartilage had better biocompatibility and suitable microenvironment for tissue regeneration in the defect area, suggesting its potential application in cartilage repair during the surgery. Statement of significance Autologous costal cartilage has been widely used in various surgeries, while the cartilage defects after the harvesting of multiple costal cartilages may cause localized chest wall deformities. Decellularized cartilage is an ideal material that could be produced in the factory and applied in surgeries. In this study, both decellularized costal cartilage and auricular cartilage preserved original structure, functional biocompatibility, immunosuppressive effects, and promoted tissue regeneration in the cartilage defect area.

Additional file 4. Supplementary materials.

Additional file 1. Additional methods. Fig. S1. mTOR senses the availability of methionine. Fig. S2. mTORC1 signaling pathway mediated Myc expression to promote HCC tumorigenesis. Fig. S3. Negative correlation of MYC and SIRT4 expression. Fig. S4. Myc regulates SIRT4 stability through proteasome degradation. Fig. S5. Characterization of the interaction between SIRT4 and TRIM32. Fig. S6. SIRT4 suppresses Myc promoted HCC tumorigenesis. Fig. S7. The effect of SIRT4 on histone methylation through regulating methionine metabolism. Fig. S8. The effect of SIRT4 retards cancer progression through regulating methionine metabolism. Fig. S9. SIRT4 regulates MARylation of MAT2A. Fig. S10. SIRT4 suppresses MAT2A promoted tumorigenesis. Fig. S11. The MAT2A inhibitor FIDAS-5 abrogates HCC cell stemness. Fig. S12. SIRT4 affects histone methylation and Myc mediated transcription. Fig. S13. SIRT4 increases the sensitivity of HCC cells to chemotherapy. Fig. S14. Comparison of c-Myc, MAT2A and MARylation level of MAT2A from clinical liver samples.

The joint of dissimilar metals between Mo2FeB2-based cermets and 316L stainless steel was welded by gas tungsten arc welding with no fillers. The weldability was investigated by plate rigid restraint cracking test and transverse rupture strength was measured by the three-point bending test. Microstructure of the weld joint was studied with scanning electron microscope, energy-dispersive spectrometer, X-ray diffractometer and differential scanning calorimeter, etc. Corrosion behavior was investigated by the potentiodynamic polarization test. Results revealed that weld solidification cracking susceptibility existed in the fusion zone. Coarse irregular complex ternary boride phase (M3B2) and hypoeutectic microstructure were formed in weld metal (WM). In heat affected zone (HAZ), a small number of M3B2 grains dissolved into the γ-Fe based binder, with growth and coalescence of the remaining M3B2 grains. Microhardness of HAZ increased slightly and WM presented the highest microhardness in the whole joint. Besides, potentiodynamic polarization test showed that WM had a better corrosion resistance than Mo2FeB2-based cermets, which can be attributed to the higher Cr content and relatively homogenous Mo distribution.

The microstructure, microhardness and corrosion behavior in five zones from the weld metal to base metal of a 2205 duplex stainless steel joint, which was welded by double-pass tungsten inert gas arc welding with filler wire, were investigated systematically. Results indicated that a great deal of secondary austenite appeared in weld metal due to the reheat of second pass welding and coarse ferrite grains were formed near the fusion line, while other zones had the similar microstructures with a different austenite content. It also revealed the microhardness was determined by the partitioning of alloying elements (Cr, Mo, Ni and N) and precipitates such as chromium nitride. Austenite was harder than ferrite from weld metal to fusion line, while it reversed from fusion line to base metal. Electrochemical measurement indicated the zone containing fusion line was the easiest to suffer pitting attack, followed by weld metal zone. Moreover, the surface morphologies were in good agreement with the electrochemical measurements.

A Grey AMSAA-ELP model based on discovery learning driven reliability growth of complex equipment is proposed in accordance with the practical cases where system's reliability can be improved by discovery learning from the development process of other related equipment. The characteristics of the model are analyzed and a maximum likelihood estimation (MLE) calculation formula is built in the cases of time terminated testing and fixed failure number testing (commonly known as Type I censoring and Type II censoring). It is pointed out that if MLE has multiple extrema, the quasi- Monte-Carlo method can be used for parameter calculation. Furthermore, test methods for goodness of fit are given. Finally, failure data from an engine with certain complex equipment are analyzed by means of the proposed method, which reveals that test data fitting the Grey AMASS-ELP model outperforms that of the Grey AMSAA, and its assessment results are more consistent with engineering practices as well.

To investigate effects of chitosan on nonspecific immunity in grass carps, five test groups were used, which consisted of control group, antibiotics group, 0.25%, 0.50% and 1.00% chitosan addition group. 450 grass carps with average body weight (70.61±1.29) g were randomly allocated to five groups with three replicates and with 30 grass carps in each replicate and were fed for 40 d. The results showed that, post kidney body index increased significantly by adding chitosan, while head kidney body index and spleen body index showed no significant difference (P0.05) among groups. 0.5% chitosan significantly impacted on serum total protein in grass carp (P0.05), however serum SOD and hepatopanereas SOD showed no significant difference (P0.05) among groups. Above results suggested that, chitosan could significantly increase nonspecific immunity in grass carps and the appropriate chitosan addition was 0.50%.

An indirect adaptive fuzzy control scheme is developed for a class of nonlinear systems with input constraint and unknown control direction. In this scheme, the fuzzy systems are used to proximate unknown nonlinear functions, a modified control design framework is presented for preventing the presence of input constraint from destroying the learning capabilities of the fuzzy systems, and the dynamic robustness term is used to compensate the approximation errors. The proposed design scheme guarantees that all the signals in the resulting closed-loop system are bounded, and the tracking error converges to the small neighborhood of the origin. Simulation results indicate the effectiveness of this scheme.

Spontaneous Combustion in Coal Seam (SCCS) is seriously threatening coal mine safety. A novel approach to predict SCCS by using Support Vector Machine (SVM) is present. The SVM is based on statistical learing theory with a simple structure and good generation properties. The basic SVM principle was firstly reviewed. Then, the kernel function was choiced, and the model parameters were optimized with cross-validation and grid-research method. Finally,a comparision of the preformance of SVM with radial basis function neural networks (RBF-NN) was carried out.The experimental results show that the highest classification accuracy (100%) is obtained for the SVM model, and the SVM-based model makes predictions much more accurate than RBF-NN model does when the samples are limited. Consequently, a properly trained SVM classification model can be a strong predictor for SCCS prediction procedure.

As the main force of a school, teachers undertake the lofty task of the all-round training of socialist construction personnel-morally, intellectually, and physically. The quality of teachers has a direct bearing on the development of the new generation being educated in schools, and a prospective bearing on the future of the nation. Therefore, building a contingent of qualified teachers is a major measure of fundamental importance for the improvement of educational qualities and the development of the cause of education.