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Traumatic brain injury (TBI) is a serious global public health problem. Survivors of TBI often suffer from long-term disability, which puts a heavy burden on society and families. Unfortunately, up to now, there is no efficacious treatment for TBI patients in clinical practice. As a reducing gas, hydrogen has been shown to be neuroprotective in multiple cerebral disease models; however, its efficacy in TBI remains controversial. In this review, we will focus on the results of hydrogen in experimental TBI, elaborate the potential mechanisms, and put forward for future researches based on our current understanding and views. [ABSTRACT FROM AUTHOR]

Considering the quantum effects of diffraction and the collective screening effects, the potential of test charge in semiclassical plasmas is derived. It is generalized exponential screened Coulomb potential. Using the Ritz variational method incorporating this potential, the effects of semiclassical plasma on the energy levels and radiative transitions are investigated systematically, taking highly charged H-like ion as an example. The Debye plasma model is also employed for comparison purposes. Comparisons and analysis are made between these two sets of results and the differences are discussed. Graphical abstract: [ABSTRACT FROM AUTHOR]

Ultrasonic technique is very promising for non destructive inspection. In this paper, a method is presented on automatic ultrasonic inspection of defects in a propeller-blade without computer aided design (CAD) models. The 3D surface data are obtained by ultrasonic measurement, and then the inspection path is planned after the CAD model has been reconstructed. A C-scan image is obtained in real-time ultrasonic automatic inspection. Thereafter, defective area and sound area are separated through binarisation of the C-scan image, and an auxiliary table is used to segment defects in order that defects are disconnected to each other. Then, an algorithm based on edge element is proposed, simplifying the process of extracting edge. Finally, application of these procedures for inspecting a propeller-blade is demonstrated. [ABSTRACT FROM AUTHOR]

The magnetic field ( 10 6 - 10 9 G) effect and the plasma shielding effect on the spectrum of hydrogen helium, and carbon in dense magnetized plasmas are studied. The results show the effect of plasma on radiative transition is radiative when plasma shielding length λ > 13.041 (a.u.). The magnetic field strength has obvious effect on 2s–3p transition of excited hydrogen-like He ions. Magnetic fields could be detected in large ranges of strength by measuring 2s–3p-1 transition probability. [ABSTRACT FROM AUTHOR]

Recent timing observation provides an intriguing result for the braking index of the X-ray pulsar PSR |$\:$| J1640 |$-$| 4631, which has a measured braking index |$n=3.15\pm 0.03$|⁠. The decrease of the inclination angle between the spin axis and the magnetic axis can be responsible for such a high braking index. However, the physical mechanisms causing the change of the magnetic inclination angle have not been fully understood. In this Letter, we apply a two-dipole model given by Hamil, Stone, and Stone (2016, Phys. Rev. D. 94, 063012) to explain the decrease of the magnetic inclination angle of PSR |$\:$| J1640 |$-$| 4631. The rotation effect of a charged sphere and the magnetization of ferromagnetically ordered material produce magnetic moments |$M_{\,1}$| and |$M_{\,2}$|⁠ , respectively. There exists a minimum of the potential energy for the magnetic moment |$M_{\,2}$| in the magnetic field of |$M_{\,1}$|⁠ , hence the |$M_{\,2}$| will freely rotate around the minimum energy position (i.e. equilibrium position), similar to a simple pendulum. Our calculation indicates that the magnetic moment |$M_{\,2}$| would evolve towards alignment with the spin axis for PSR |$\:$| J1640 |$-$| 4631, and cause the magnetic inclination angle to decrease. The single peak in the pulse profile favors a relatively low change rate for the magnetic inclination angle. [ABSTRACT FROM AUTHOR]

Supercharging is the main method to improve the output power of marine diesel engines. Nowadays, most marine diesel engines use turbocharging technology, which increases the air pressure and density into the cylinder and the amount of fuel injected correspondingly so as to achieve the purpose of improving the power. In a marine diesel engine, the turbocharger has become an indispensable part. The performance of turbochargers in a harsh working environment of high temperature and high pressure for a long time will directly affect the performance of diesel engine. Based on the market feedback data from manufacturers, the failure modes of compressor impeller, turbine blade, and turbine disk of marine diesel turbocharger are analyzed, and the statistical model of random factors is established. Using DOE design, the structural strength simulation data of 46 compressors and 62 turbines are obtained, and the response surface model is constructed. On this basis, Monte Carlo sampling is carried out to analyze the reliability of the compressor and turbine. The reliability of the compressor is good, while that of the turbine disk is 0.943 and that of the turbine blade is 0.96, which still has the potential of reliability optimization space. Therefore, a multiobjective optimization method based on the NSGA-II genetic algorithm is proposed to obtain the multiobjective optimization scheme data with the reliability and processing cost of turbine disk and blade as the objective function. After optimization, the reliability of turbine disk and blade is 1, the stress value of turbine blade is optimized by 4.7941%, the stress value of turbine disk is optimized by 3.0136%, the machining cost of the turbine blade is reduced by 15.5087%, and the machining cost of turbine disk is reduced by 3.9907%. At the same time, it is verified by simulation, the data based on NSGA-II multiobjective genetic algorithm are more accurate and have practical engineering reference value. The optimized data based on NSGA-II multiobjective genetic algorithm are used to manufacture new turbine samples, and the accelerated test of simulation samples is carried out. The cycle life of the optimized turbine can reach 101,697 cycles and 118,687 cycles, which is 51.75% and 77.11% longer than that of the unoptimized turbine. It can be seen that the optimized turbine can meet the requirements of the reliability index while reducing the manufacturing cost. [ABSTRACT FROM AUTHOR]

The high-temperature deformation behavior of GH4698 superalloy was explored via isothermal compressive tests under transiently varying strain rates. The impacts of loading types and deformation temperature on flow stress, microstructural evolution, and microhardness were explored, and the underlying nucleation mechanisms for dynamic recrystallization (DRX) were elucidated. Experimental results indicated that the flow stress decreased when the strain rate decreased transiently. Specifically, under loading type I (interrupted strain = 0.11), the flow stress was higher than that under loading type II (interrupted strain = 0.36). Moreover, the flow stress decreased with increase in deformation temperature. When the initial interrupted strain was high, a high degree of DRX was observed in the deformed microstructure. The DRX fraction of types I and II are 48 % and 61 %, respectively. Higher deformation temperatures accelerated the growth of DRX grains, and at a deformation temperature of 1100 °C, DRX fraction reaches 87 %. The microhardness of the DRX grains was higher than that of the deformed grains. At higher deformation temperatures, the γ′ phase dissolved, and the DRX grains grew, resulting in smaller microhardness of the DRX grains than that at lower deformation temperatures. However, microhardness was not sensitive to the loading type (i.e., the value of interrupted strain). Furthermore, discontinuous dynamic recrystallization (DDRX), activated by the initial bulging of grain boundaries, served as the fundamental mechanism for DRX nucleation. Similarly, continuous dynamic recrystallization (CDRX), characterized by the formation of subgrains through dislocation cell structures within individual grains, as well as the γ′ phase and twin boundaries, also played crucial roles in the nucleation of DRX during transiently variation states conditions. [ABSTRACT FROM AUTHOR]

Bioethanol fermentation is usually contaminated by bacteria, especially lactic acid bacteria (LAB), thereby leading to decrease of bioethanol yield and serious economic losses. Nisin is safer for controlling of bacterial contamination than antibiotics that are widely applied in industry. Moreover, in LAB contaminative bioethanol fermentation system, consistently decreased pH value provides opportunity to realize pH value responsive material-based release of anti-bacteria substances for intelligent and persistent controlling of bacterial contamination. In this study, nisin was embedded into pH-sensitive poly(4-vinylpyridine) (P4VP) microspheres synthesized by suspension polymerization to realize intelligent controlling of Lactobacillus plantarum contamination in bioethanol fermentation. Chloramphenicol with the highest antimicrobial activity and excellent stability was chosen as the model drug to be embedded into P4VP microspheres to test the drug release behavior. The drug release curve of chloramphenicol-loaded P4VP microspheres showed sustained and pH-responsive release properties. The diameters of the microspheres ranged from 40 to 100 µm. The encapsulation efficiency of nisin into P4VP microspheres was 47.67% and the drug-loading capacity of nisin was 2.5%. Nisin-loaded P4VP microspheres were added into the simulated contaminative fermentation system, and successfully reversed the decline of bioethanol yield secondary to L. plantarum contamination. The results in this study indicated that L. plantarum contamination in bioethanol fermentation could be effectively controlled by nisin-loaded P4VP microspheres. [ABSTRACT FROM AUTHOR]

The studies of the influence of plasma environments on the level structures and transition properties for highly charged ions are presented. For the relativistic treatment, we implemented the multiconfiguration Dirac-Fock method incorporating the ion sphere (IS) model potential, in which the plasma screening is taken into account as a modified interaction potential between the electron and the nucleus. For the nonrelativistic treatment, analytical solutions of the Schrödinger equation with two types of the IS screened potential are proposed. The Ritz variation method is used with hydrogenic wave function as a trial wave function that contains two unknown variational parameters. Bound energies are derived from an energy equation, and the variational parameters are obtained from the minimisation condition of the expectation value of the energy. Numerical results for hydrogen-like ions in dense plasmas are presented as examples. A detailed analysis of the influence of relativistic effects on the energy levels and transition properties is also reported. Our results are compared with available results in the literature showing a good quantitative agreement. [ABSTRACT FROM AUTHOR]

Systematic investigations are performed for the energy levels and radiative properties for selected He-like C4+, Ne8+, Ar16+, and Kr34+ ions embedded in weakly coupled plasmas. For the conditions in which the Coulomb coupling parameter is small, the standard Debye model is adopted to describe the plasma screening effects. Within the relativistic framework, the modified version of the Flexible Atomic Code computations is carried out by considering a Debye-Hückel potential, in which the plasma screening is taken into account for both the electron-nucleus and electron-electron (e-e) interactions. An independent calculation for various Debye lengths is also presented using the multiconfiguration Dirac-Fock method for comparison purposes. For the nonrelativistic treatment, the analytical solution of the Schrödinger equation with the Debye screened potential is proposed. The variation method is developed with Slater wave function as a trial wave function that contains the variational parameters. An exact analytical expression of relativistic corrections such as the mass-velocity correction, the one/two-body Darwin correction, the spin-spin contact interaction correction, and the orbit-orbit interaction correction is derived. Differences among our three kinds of calculated energy levels and transition properties are analyzed in terms of the nuclear charge and/or the Debye length. Systematic trend is observed for all the properties under study with respect to increased screening. The influence of relativistic effects is also investigated in detail and found to play an important role in these systems. Our results are compared with available results from other theoretical calculations and the experimental values in the literature, and a good agreement is achieved. This work should be useful for astrophysical applications where such plasma environments exist. [ABSTRACT FROM AUTHOR]

The hot compressive behavior of GH4698 superalloy is examined in the temperature range of 950–1100 °C and strain rate range of 0.001–1 s−1. The observations from the flow stress curves reveal work hardening and dynamic recovery features at the beginning of the deformation, which leads to rapid increase in the true stress. After the true stress exceeds its peak level, the dynamic softening induced by dynamic recrystallization (DRX) becomes dominant, and the true stress gradually drops until a relatively stable stress level. Considering the coupled impact of temperature and strain rate, an improved Zhu-Ou-Popov (ZOP) model is proposed to characterize the hot deformation behavior of the tested superalloy. The results verify the accuracy of the improved ZOP model for reproducing the hot deformation behavior of the tested superalloy with a correlation coefficient as high as 0.9721. Additionally, the processing maps are established according to the dynamic material model. Furthermore, the microstructural evolution is examined to validate the feasibility of the established processing maps. The results reveal that the processing maps can be decomposed into three domains: an unstable region, a stable region with low power dissipation, and a stable region with high power dissipation. The main instability regions are 950–1050 °C, 0.04–1 s−1 and 1095–1100 °C, 0.1–0.22 s−1, where obvious microcracks and mixed grains can be observed. The stable zone with low power dissipation consists of three parts: 1040–1100 °C, 0.1–1 s−1, 1040–1100 °C, 0.02–0.1 s−1; 950–1065 °C, 0.001–0.04 s−1. In these regions, the primary elongated grains and small DRX grains are the predominant microstructures. The stable region with high power dissipation is observed at 1010–1100 °C and 0.001–0.1 s−1, where the DRX grains are found to be fine and uniform, and it is the optimal hot working window to achieve the desired performance of the tested superalloy. • The flow characteristics of GH4698 superalloy under hot compression was revealed. • An improved ZOP model is formulated to correlate the true stress, deformation temperature, strain rate, and true strain. • Hot processing maps are constructed to identify the feasible hot working windows. • Selected microstructures under different deformation domains are examined to calibrate the established hot processing maps. [ABSTRACT FROM AUTHOR]

There exists a great need for repair grafts with similar volume to human skeletal muscle that can promote the innate ability of muscle to regenerate following volumetric muscle loss. Perfusion decellularization is an attractive technique for extracellular matrix (ECM) scaffold from intact mammalian organ or tissue which has been successfully used in tissue reconstruction. The perfusion-decellularization of skeletal muscle has been poorly assessed and characterized, but the bioactivity and functional capacity of the obtained perfusion skeletal muscle ECM (pM-ECM) to remodel in vivo is unknown. In the present study, pM-ECM was prepared from porcine rectus abdominis (RA). Perfusion-decellularization of porcine RA effectively removed cellular and nuclear material while retaining the intricate three-dimensional microarchitecture and vasculature networks of the native RA, and many of the bioactive ECM components and mechanical properties. In vivo , partial-thickness abdominal wall defects in rats repaired with pM-ECM showed improved neovascularization, myogenesis and functional recellularization compared to porcine-derived small intestinal submucosa (SIS). These findings show the biologic potential of RA pM-ECM as a scaffold for supporting site appropriate, tissue reconstruction, and provide a better understanding of the importance maintaining the tissue-specific complex three-dimensional architecture of ECM during decellularization and regeneration. [ABSTRACT FROM AUTHOR]

We report the LD-pumped continuous-wave (CW) thin-disk Yb 3+ -doped Lu 2 O 3 laser at 1034 nm. The maximum output power is 1.17 W with a 7.8% output coupler and under a pump power of 18.6 W. Moreover, intracavity second-harmonic generation (SHG) has also been achieved with a power of 192 mW at 517 nm by using a LiB 3 O 5 (LBO) nonlinear crystal. The M 2 factors are about 1.14 and 1.28 in X and Y directions respectively. The fluctuation of the output power is about 2.7% in 4 h. [ABSTRACT FROM AUTHOR]

LRP (low-density lipoprotein receptor-related protein) is linked to Alzheimer''s disease (AD). Here, we report amyloid β-peptide Aβ40 binds to immobilized LRP clusters II and IV with high affinity (Kd = 0.6–1.2 nM) compared to Aβ42 and mutant Aβ, and LRP-mediated Aβ brain capillary binding, endocytosis, and transcytosis across the mouse blood-brain barrier are substantially reduced by the high β sheet content in Aβ and deletion of the receptor-associated protein gene. Despite low Aβ production in the brain, transgenic mice expressing low LRP-clearance mutant Aβ develop robust Aβ cerebral accumulations much earlier than Tg-2576 Aβ-overproducing mice. While Aβ does not affect LRP internalization and synthesis, it promotes proteasome-dependent LRP degradation in endothelium at concentrations >1 μM, consistent with reduced brain capillary LRP levels in Aβ-accumulating transgenic mice, AD, and patients with cerebrovascular β-amyloidosis. Thus, low-affinity LRP/Aβ interaction and/or Aβ-induced LRP loss at the BBB mediate brain accumulation of neurotoxic Aβ. [Copyright &y& Elsevier]

We develop a new relativistic model which can describe the dynamics on electron-impact excitation (EIE) of ions within a quantum plasma environment. An exemplary excitation 1 s 1/2 → 2 p 3/2 of Fe XXVI by electron impact with the exponential cosine-screened Coulomb potential (ECSCP) is presented, i.e., 25 times ionized atoms of Fe, exist in laser-produced plasmas, astrophysical objects, and electron beam ion trap experiments. For the atomic structure of target ion, using the same potential, a Ritz variational method with a trial wave function that contains unknown variational parameters is also proposed for comparison purposes. In this method, an analytical formula of bound energy is derived from the energy equation, and the variational parameters are determined by the minimization of the energy. The energies obtained from our two methods are compared with each other and other theoretical predictions based on the non-relativistic model and found to be in good agreement. For the collision dynamics, the continuum wave function is determined by solving the modified Dirac equations, in which the ECSCP is included for the solution of the continuum orbital. The total cross sections, magnetic sublevel cross sections, and the degrees of linear polarization of emitted x-rays are calculated as a function of the incident energy and screening parameter by using the distorted-wave method in the relativistic frame. Since there are no experiments or other calculations for EIE cross sections on this ion, the obtained results have been compared with those for an isolated ion. The effect of quantum plasma leads to a reduction in the total and magnetic sublevel cross-sections and thus reduces the degrees of linear polarization of emitted x-rays. Comparative analysis allows to estimate the quality of the proposed approximations. Our dynamic model is practicable and easy to apply, which may provide an alternative route towards information with fluorescence polarization in a quantum plasma environment. • We have developed a model to calculate the EIE process within a quantum plasma. • The present models compare well, with existing methods and experimental data. • The present results will be rewarding in interpreting the laboratory plasma. [ABSTRACT FROM AUTHOR]