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The rapid growth of grain yield in China accelerates a discussion on whether the grain system in China is sustainable. To answer the question, a comprehensive assessment from economic and environmental points is necessary. This study jointly used economic analysis (ECA), emergy evaluation (EME) and carbon footprint (CF) to analyze the environmental and economic sustainability of the grain production system in China based on the national statistical data during 2000–2015. Results showed that the costs of maize, wheat, rice and soybean had increased by 252–346% from 2000 to 2015, causing the lower profit of grain system in recent years. The situation resulted in a serious problem on economic sustainability of grain system in China. Meanwhile, the emergy sustainability index (ESI) of maize, wheat, rice and soybean systems were increasing during 2000–2015, and the CF on unit yield of the crops had been reduced by 10–30% in the study period. The results reflected the improved environmental sustainability of grain system in China during 2000–2015. Nevertheless, the emergy flow of industrial inputs for the crops were increased by 4–22% in the study period, and the CF from the inputs presented a growth rate of 16–23% as well during the same period. The results implied that the grain system in China was relying more on fossil-based inputs. Finally, according to the key points of cost, emergy and CF, we suggest that improving labor efficiency, advanced agricultural practices and optimizing cropping pattern will be effective ways to further improve the economic and environmental sustainability of grain system in China.

Recycling agriculture is an effective way to reduce greenhouse gases (GHGs) emissions and improve yield of agricultural systems. The core practice of the recycling agriculture model is to extend the industrial chain of agricultural activities and to return the wasted organic materials that resulted from each step of the recycling chain into farmland for completely treating them. In this context, people is asking a question about if the longer recycling chain means the better effectives on yield growth and agricultural GHGs mitigation. For answering the question, therefore, this study compared the yield and net GHGs emissions by applying mineral fertilizer (CK), rice straw (CS), cow manure (CM), biogas residue (BR) and commercial organic fertilizer (MO) into paddy field during 2017–2018 in the South China. All of the organic materials were derived from the different steps of recycling chain of rice straw. The results indicated that the yields of CS, CM, BR and MO were 9.4%, 12.7%, 19.7% and 14.2% higher than CK, respectively. The field-based net GHGs emissions (NGHGD) of CS, CM, BR and MO were 7.2%, 9.7%, 24.1% and 66.4% lower than the CK, respectively. The results demonstrated that, from the farmland level, extending recycling chain of using rice straw indeed contributed to improving yield and reducing GHGs emissions in paddy field. Nevertheless, if the NGHG accounting of different treatments considered the upstream GHGs emissions under the condition of ignoring substituted effects, the longer recycling chain of using rice straw did not contribute to reducing the NGHG of the whole recycling agriculture pathways. Specifically, the system-based net GHGs emission (NGHG) of CS was decreased by 13.0% compared to the CK, while the indices of CM, BR and MO were increased by 96.0%, 14.7% and 26.6%, respectively. The information will contribute to the development of circular economy and clean production in agricultural systems.

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma. The chromo-helicase-DNA binding proteins (CHDs), containing nine members named CHD1-9, act as regulators of the chromatin remodeling process and gene expression. To determine the correlation between CHD9 expression and ccRCC, we performed an immunohistochemical staining in a tissue microarray (TMAs) containing tissue samples from 88 ccRCC patients. The results showed that cytoplasm CHD9 expression was statistically decreased in tumor tissues compared to adjacent tissues (8.54±2.90 vs 12.61±2.05, P=0.000), while nuclear CHD9 expression was upregulated in the tumor tissues (1.47±2.93 vs 0.29±1.24, P=0.000). A univariate analysis found that cytoplasm CHD9 expression in cancer tissues was correlated with the patients’ pathological grading (P=0.002, r=0.330), the clinical stages (P=0.02, r=0.250) and the T grading (P=0.024, r=0.241) significantly. In addition, cytoplasm CHD9 expression in non-tumor tissues was correlated with the ccRCC patients’ pathological grading (P=0.031, r=-0.231) significantly. Patients with high cytoplasm CHD9 expression had a significantly worse prognosis than those with low cytoplasm CHD9 expression levels (59.7% vs 85.7%, P=0. 042). In conclusion, our study indicated the important role of CHD9 in ccRCC and suggested CHD9 may be a potential biomarker for prognostic prediction and a new target for therapy.

Recently, how the desert lizards run, hide or swim in the sand has attracted much attention of many scientists in granular matter field, and many valuable results have been published, except for the Phrynocephalus mystaceus, a type of the desert lizard, which can embeds itself into the sand through a motion mode which is completely different from other types of desert lizards. To illuminate the roles played by the spinning-mode in the Phrynocephalus mystaceus' motion in the sand, the three-dimentional (3D) numerical simulation using the Hertz model on the system, in which one sphere is spinning in the granular matter, is carried out with the open-source code LIGGGHTS released by the Sandia National Laboratory in USA. In the numerical simulations for all the cases, the initial conditions are the same and the sphere spins around X-axis while the X-Y plane is the horizontal plan and the Z axis is the vertical direction. According to the numerical results and analyses, for the spinning sphere deeply embedded in the granular matter we can draw some conclusions. 1) The X-axis spinning motion can cause the sphere embedded in the granular to notably displace along the Z-axis and Y-axis, but the displacement along the spinning direction is smaller than the sphere diameter. 2) The friction coefficient between the sphere and the granular matter has a notable influence on the motion of the sphere in granular matter, the spinning sphere can move vertically and horizontally only when the friction coefficient between the sphere and the granular matter is larger than that of the granular matter; and the bigger the , the more violent the movement of the sphere is. This can be used to explain why most of the desert creatures each have a coarse skin. 3) On the premise that the friction coefficient between the sphere and the granular matter is larger than that of the granular matter, the spinning velocity of the sphere also has a great influence on the movement of the sphere in the granular matter. In a spinning velocity range between 10 rad/s and 640 rad/s, the larger the , the more obvious the movement of the sphere is. When the spinning velocity reaches 1280 rad/s, the movement of the sphere slightly decreases compared with when the spinning velocity is 640 rad/s. 4) For the spining sphere in granular matter, the sphere always moves upward in the Z direction, but in the Y direction the sphere may move in a positive or negative direction depending on the and . The sphere moves in the positive direction of Y axis if the and are relatively small, while it moves in the negative direction if the and are larger.

It has great significance to study the thermal-mechanical effects of X-ray in assessing the viability of space-crafts, the penetration ability of missiles and testing the effectiveness of the anti-nuclear reinforcement measures. However, it is rather difficult to construct a suitable X-ray source in laboratory. During recent decades, pulsed electron beam with multi-energy composite spectrum has become a most important simulation source of X-ray to study its thermal-mechanical effects. And energy deposition profile in target material is the basis for studying the thermo-mechanical effects. However, under the same incident conditions, the energy deposition profile of pulsed electron beam with multi-energy composite spectrum in target material is extremely different from X-ray's, and the equivalence between the two beams is quite low. Thus, it is very important to adjust the energy spectrum and the incident mode of pulsed electron beam so as to improve their equivalence. In this paper, we use the energy deposition profiles of electron beam and X-ray in different kinds of material. MCNP is used to calculate their energy deposition profiles in target materials. Two kinds of blackbody X-rays with the equivalent temperatures of 3 and 5 keV and energy density of 200 J/cm2 are chosen for an optimization target. Aluminum, copper and titaniumare chosen as the target materials. Based on the change law of electron beam's energy deposition profile when the electron beam hits the target material at different incident angles, a theoretical model is established. Then, taking advantage of simulated annealing algorithm, we use the MATLAB to carry out numerical calculation and finally the numerical optimization results about the incident angle spectrum and energy density of electron beam are obtained. After optimization, the energy deposition of pulsed electron beam with multi-energy composite spectrum is well adjusted. The peak energy deposition and change of gradient of electron beam are of wonderful consistency with X-ray's. The equivalence of pulsed electron beam with multi-energy composite spectrum in simulating X-ray is also effectively improved. However, the energy density of adjusted pulsed electron beam should be much higher than 200 J/cm2. Electron beam designed by this paper can be used to better simulate the thermal-mechanical effects of X-ray in different kinds of materials.

The equations of state (EOS) and the thermodynamics properties of plasma under high temperature are widely applied to the fields of astrophysics, controllable fusion, weapon design and damage. In this paper we mainly review the theoretical model and computing method of the EOS of hot plasma on different density scales and temperature scales. For an ideal plasma, the interaction between ions can be ignored, the EOS is simple and the theories turn matured. Under the condition of extremely high temperature, ions are ionized completely and the EOSs of ions and electrons can be approximated by the EOS of ideal gas. When the temperature is not very high and ions are just partly ionized, the EOS can be obtained by Saha model or its modified model. When atoms are strongly compressed, the EOS can be calculated by Thomas-Fermi model or its modified model. For the non-ideal plasma, there is a strong coupling between ions. No unified theoretical model can completely describe the interaction between ions at arbitrary density and arbitrary temperature. In principle, the quantum molecular dynamics (QMD) can accurately describe the EOS of plasma in large density range and large temperature range. However, due to the enormous computation and the difficulty in converging, it is difficult to apply QMD to the plasma under high temperature. With simple computing method and small computation, classical molecular dynamics using semi-empirical potential can calculate the EOS accurately at high temperature. However, it will produce great error at lower temperature. It is a simple and effective way to obtain a global EOS by using different theoretical models in different density range and different temperature range and by interpolating in the vacant density range and vacant temperature range.

Dynamic yield strength is one of the key variables in construction of the constitutive relationship for solids under shock loading. This paper reports the yield strength of LY12 aluminum alloy which was measured experimentally on the basis of the method proposed by J. R. Asay and L. C. Chhibildas, in which the test sample underwent a load-reload process and a load-unload process, and the particle velocity history at the LY12 Al sample/LiF transparent window interface was observed by velocity interferometer system for any reflecting surface (VISAR). Improvement in fabrication of the layered flyer plate made these experiments successful. The measured yield strength data at shock stresses of 22GPa and 34GPa are consistent with the reported data at relatively lower pressures. Moreover, physical mechanism of the elastic precursor emerging in the reloading-process was discussed briefly. It is concluded that dislocations is the principal factor resulting in the elastic precursor.

Basing on the modified SCG model, a high temperature and high pressure constitutive relation of materials is proposed. The change of shear modulus of aluminum with pressure as deduced from this model shows three stages: machining indurations, high temperature inteneration and melting, and turning to zero at the point of complete melting. In the first two stages, the difference in results of modified SCG model and our model is no greater than 4%, which is in the error range of dynamic experiments, and the shear modulus given by this model is in good agreement with experimental data at the point of 145GPa.