Search

The efficacy of immune checkpoint inhibitors (ICIs) on KRAS-mutant advanced non-small cell lung cancer (NSCLC) remains controversial. This retrospective study compared the effects of ICIs treatment and chemotherapy on the prognosis of patients with KRAS-mutant advanced NSCLC and different mutant subtypes in the real world. The study included 95 patients with KRAS-mutant advanced NSCLC. Patients treated with first-line ICIs plus platinum-containing chemotherapy had better progression-free survival (PFS) (7.4 vs 4.5 months, P = 0.035) and overall survival (OS) (24.1 vs 13.2 months, P = 0.007) than those receiving platinum-containing chemotherapy alone, and second-line ICI monotherapy was associated with better PFS (4.8 vs 3.0 months, P = 0.043) and OS (18.0 vs 13.8 months, P = 0.013) than chemotherapy monotherapy. There was no significant difference in PFS (5.267 vs 6.734 months, P = 0.969) and OS (19.933 vs 20.933 months, P = 0.808) between patients with KRAS-mutant and KRAS-wild-type NSCLC treated with ICIs or between KRAS G12C and KRAS non-G12C patients (PFS: 8.1 vs 4.8 months, P = 0.307; OS: 21.3 vs 21.8 months, P = 0.434). In summary, patients with advanced NSCLC with KRAS mutations can benefit from ICIs, but no difference between KRAS mutant subtypes was observed.

The competition for cyber security is ultimately the competition of talents. Countries around the world have placed cyber security talents at the national strategic level. As a new interdisciplinary subject, the intension and extension of cyber security discipline is still evolving and developing. So far, it lacks a talent training mode and evaluation mechanism suitable for the characteristics of cyber security talents. Based on years of teaching research, with reference to the existing advanced training models and evaluation mechanisms in foreign countries, combined with the actual situation in China, an innovative training mode of “cybersecurity doctor” suitable for the characteristics of cybersecurity disciplines is proposed. It covers the whole life cycle of undergraduate training. With problem orientation, students are trained to find security problems and solve them in cyberspace. Universities, industry and research institutions are closely interacting. Furthermore, it improves students' knowledge, skills and practical application ability, develops interest and ability to explore the latest advanced and core technologies, improves the quality of our teachers and education, and also helps enterprises select outstanding talents, enhance their research and development capabilities and market competitiveness. In the end, the two sides will achieve synergy and innovation, complement each other, and achieve a comprehensive win-win situation, and promote the cultivation of cyber security talents and the development of disciplines.

BackgroundBoron carbide (B4C) aluminum matrix composite has a wide application prospect in the field of nuclear power plant spent fuel storage shielding neutron due to the large neutron absorption cross section of B isotope 10B in B4C.PurposeThis study aims to investigate the response mechanism of current effect on the internal microstructure and mechanical properties of neutron absorbing materials.MethodsThe 30wt.% B4C/6061Al neutron absorbing material was prepared by multi-pass rolling after vacuum hot pressing. Electropulsing treatment (EPT) was applied to the heat treatment of prepared materials, and the skin effect and joule effect of current were made use of eliminating the defects and residual stresses at the particle/matrix interface. Finally, energy disperse spectroscopy (EDS), electron backscatter diffractometer (EBSD) and scanning electron microscope (SEM) were employed to observe the microstructure morphology and particle / matrix interface of the samples under different process parameters.ResultsThe results show that the EPT can promote the degree of recrystallization of the matrix alloy, healing heterogeneous particle/matrix interface of micro defects, improve the bonding strength of interface, inhibit grain growth of the matrix alloy, and reduce the interfacial residual stress. With the extension of time of applying pulse current, the tensile strength and elongation of the composite material showed a trend of increase, up to 245.2 MPa and 9.02%, the load transfer effect of B4C particles is enhanced, and the non-thermal effect of current play a leading role.ConclusionsEPT can improve the mechanical properties of B4C aluminum base neutron absorbing material.

In this study, a finite element model of the explosive welding process of three-layer plates composed of Ti/Al/Mg was established, and the interfacial behaviors of three-layer plates were researched. We investigated the influences that affect the quality of explosive bonding and explored the influence factors of variable physical parameters in the simulation. The finite difference engineering package AUTODYN with the smoothed particle hydrodynamics method has been used to model the collision in this work. The von Mises strength model was used to describe the behavior of Ti/Al/Mg composite plates. Wave morphology on the Al/Mg interface and straight morphology on the Ti/Al interface were produced in this study; meanwhile, jet phenomenon occurred obviously in the simulation process. The contours of velocity, pressure, shear stress, and effective plastic strain of Ti/Al/Mg were also discussed. The result of X-direction velocity showed a delay in time and location of collision point between the Ti/Al and the Al/Mg interface. The detonation point was the minimum pressure, and the collision point was the maximum pressure compared with other sections. The value of effective plastic strain must exceed a threshold to obtain a good bonding, and the shear stress was of opposite sign in the simulation.

In this study, the process of explosive welding of Mg/Al plate is represented, and the interfacial behavior of two metals is researched. The objective of this work is to investigate the factors that affect the quality of explosive bonding and the distribution of physical parameters on the collision. A finite difference engineering package with smoothed particle hydrodynamics method is used to model the oblique impact of a thin flyer plate (Al) on a relatively thick base plate (Mg). Wavy interface and jetting phenomenon, which existed in the experiment, are well reproduced in the simulation. The contours of pressure, shear stress, velocity, and effective plastic strain of magnesium and aluminum are also distinctly described. The bonding turns out to be a possible solid-state welding process. The effective plastic strain exceeds a minimum value, and the shear stress is just the opposite sign in this simulation where available bonding occurred. Wave formation appears to be the result of variation in the velocity distribution on the interface and periodic disturbances of magnesium and aluminum. A transition from straight to wave occurs along the interface. High values of plastic strain of two metals are predicted on the interface.

The shot peening (SP) method was employed to modify the surface properties of 33% B4C/Al composites. The microhardness, morphology, and corrosion behavior of B4C/Al composites were characterized by using the Vickers hardness test, scanning electron microscopy, potential dynamic scanning, and electrochemical impedance spectroscopy. The experimental observations revealed that the B4C particles were embedded into the matrix, which rendered the plastic deformation of Al alloy near the surface of B4C/Al composites on the condition of the high-speed impact of projectiles. As such, the density and hardness of the B4C/Al composite modified layer near the surface were enhanced. After the SP treatment, the results of the electrochemical polarization curve test showed that the corrosion potential increased by 55.2 mV, the corrosion current changed from 3.828×10-6 to 1.102×10-6 A/cm2, and the corrosion rate decreased by 72.2%, respectively. This indicates that the corrosion resistance significantly improved via the SP treatment. The mechanism of the formation of Al alloy modified layer and electrochemical corrosion behaviors is discussed in detail.