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In this study, silver carp myofibrillar protein (MP) was oxidized with different concentrations of H2O2 (0.0‒10.0 mmol/L) in the Fenton system (H2O2-VC-FeCl3) to explore the effect of oxidation degree on protein gel formation and gel properties. The sulfhydryl content of MP was measured. The gel strength, whiteness, water-holding capacity, moisture distribution and microstructure of MP gels were determined. The results showed that as H2O2 concentration increased, the total sulfhydryl content, whiteness and water-holding capacity of MP increased first and then decreased. When the H2O2 concentration in the system was low (0.1‒0.5 mmol/L), the gel strength and whiteness were both improved. The area of pores in the three dimensional gel structure became smaller, the distribution became more uniform, and the water-holding capacity of MP gels was enhanced. However, at high H2O2 concentration (5.0‒10.0 mmol/L), the gel whiteness decreased, and the gel structure became disordered, the pore area became larger, the pore distribution became nonuniform, and the water-holding capacity decreased, indicating a deterioration in gel quality. Therefore, appropriate oxidation (0.1‒0.5 mmol/L H2O2) contributed to the improved properties of protein gels. The analysis of the peptide composition by liquid chromatography-tandem mass spectrometry (LC-MS/MS) showed that the major oxidation regions of MP by hydroxyl radicals were the heavy chain of myosin and actin. Moreover, methionine, cysteine, aspartic acid and glutamic acid were recognized as the high-frequency oxidation sites of MP.

DNA damage repair and innate immunity are two conserved mechanisms that both function in cellular stress responses. Recently, an increasing amount of evidence has uncovered the close relationship between these two ancient biological processes. Here, we review the classical function of factors involved in DNA repair, and especially double-strand break repair, in innate immunity; more importantly, we discuss the novel roles of DNA repair factors in regulating innate immunity and vice versa. In addition, we also review the roles of DNA repair, innate immunity and their crosstalk in human diseases, which suggest that these two pathways may be compelling targets for disease prevention and treatment.

At present，lightweight armour has been fitted in foreign military helicopters for gunships and transport. By contrast，the armor configuration of domestic helicopters is still a big gap compared with Europe and America in the level type，quantity and single aircraft area. With more requirements of new generation military helicopters' projected-retarded survivability are raised，the development of new armor materials has also made great progress at home and abroad. In this paper, the development of composite bulletproof armor for armed helicopters is reviewed, future development needs are summarized, projected-retarded mechanism，selection principle of material and the way of energy absorption in the process of weapons is analyzed, and application prospect in military helicopters of new materials such as functionally graded materials, micro-laminated material，graphene modified ceramic is looked forward. Due to the independent development needs of helicopters in China, it is urgent to develop new advanced lightweight protective materials with excellent performance. Only by developing new armor materials can improve the survivability of our helicopters, meet the requirements of our weapons, and achieve the synchronous development with the world’s advanced helicopter level.

Objective To investigate the value of quantitative and semi-quantitative parameters of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in evaluation of the extramural venous invasion (EMVI) in rectal cancer. Methods A total of 76 patients with rectal cancer who underwent preoperative DCE-MRI examination and total mesorectal excision in our hospital from November 2016 to June 2018 were enrolled, and the results of the examination was collected and analyzed retrospectively. The entire tumor regions of interest (ROIs) for rectal cancer was drawn, and the quantitative [volume transfer constant (Ktrans), rate constant (Kep), volume fraction of extravascular extracellular space (Ve), and volume fraction of plasma (Vp)] and semi-quantitative parameters [initial area under curve (iAUC), time to peak (TTP), Max Slope, and Max Conc] of DCE-MRI were extracted using a third-party post-processing software, Omni Kinetic (OK). Each of the parameters between the EMVI positive and the negative groups was compared to analyze their respective diagnostic efficacy, and the correlation between each parameter and EMVI was analyzed. Results The intraclass correlation coefficient for each parameter extracted by 2 physicians was excellent in this study. The Ktrans and Ve values were significantly higher in the EMVI positive group than the negative group (P < 0.05), while the Kep and Vp values and the values of all semi-quantitative parameters showed no statistical differences between the 2 groups (P>0.05). The Ktrans (r=0.353, P=0.002) and Ve (r=0.417, P < 0.001) values were positively correlated with EMVI, respectively. When the Ktrans value is larger than 0.870 or Ve value than 0.556, good diagnostic performance was obtained in identifying EMVI with the area under the curves (AUC) of 0.728 and 0.769, respectively, and Ktrans had a higher specificity (90.9%) in excluding EMVI. But, the combined application of the 2 parameters had no effect on improvement of diagnostic performance (AUC=0.779). Conclusion DCE-MRI quantitative parameters Ktrans and Ve values have important application value in preoperative evaluation of rectal cancer EMVI.

The 7050 aluminum alloy samples were prepared from as-atomized 7050 aluminum alloy powder through cryomilling, hot isostatic pressing, hot extrusion and T6 heat treatment. The influence of cryomilling on morphology, grain size and microscopic strain of aluminum alloy powder were analyzed by SEM and XRD. The influence of cryomilling on microstructure and mechanical property of the sample after heat treatment was analyzed by OM, EBSD, TEM, XRD, microhardness and tensile test. The results show that cryomilling can effectively refine the grain size of the material and increase the number of nano-precipitates in the matrix. Compared to the as-atomized powder, the mechanical properties of the 7050 aluminum alloy sample prepared by cryomillied powder are obviously improved.

A new type composite rotary percussion drilling tool was designed by studying the conversion mechanism of rotary to reciprocating motion. High-frequency axial impact and vibration was generated by an impact and energy transfer mechanism consisting of a couple of mating cams. A new kind of high rock breaking efficiency method was provided by combining the high speed rotation of positive displacement motor（ PMD） with the high-frequency impact of impactor. Detailed structural design and working principle analysis was carried out on impact and energy transfer mechanism,righting and falling and abrasion proof mechanism,power and binding mechanism,using software Creo Parametric 2. 0. Three dimensional solid modeling and the whole assembly of impact and energy transfer mechanism was completed. Motion simulation and indoor principle verification test were carried through. Results show that rotary power can be transferred into followers’ reciprocating impact by the impact and energy transfer mechanism,and that the tool ’s working principle is feasible,and it has simple structure and a good application prospect.

Inspired by the global budget concept in health care, we propose an innovative subsidy scheme in which governments do not commit the subsidy amount in advance but determine it by the end of the subsidy period. The performance of the traditional and proposed subsidy schemes is evaluated in an oligopoly without competition, where each manufacturer decides its product quality and production quantity under the diseconomies of scale in production. Both types of schemes can take into account product quality or not. Our results show that compared to the traditional scheme, the proposed scheme drives manufacturers to reduce production quantity but improves product quality and brings them higher profits. Furthermore, the scheme results in greater social welfare when the subsidy budget is large. Finally, we conduct robustness checking by considering the market competition and absence of the diseconomies of scale, respectively. The result shows that the main findings in the basic model continue to hold, while there are additional findings. In the first scenario, as the market competition intensity increases, our proposed scheme becomes more preferable to the manufacturers and the government. In the second scenario, subsidy schemes that take product quality into account are never preferable. [ABSTRACT FROM AUTHOR]