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本文报道1例老年男性患者，因劳力性胸痛入中日友好医院行冠状动脉造影示右冠状动脉近段严重狭窄，置入冠状动脉支架后患者即刻出现剧烈胸痛，心电图示V

The radial velocity (RV) is a basic physical quantity which can be determined through Doppler shift of the spectrum of a star. The precision of RV measurement depends on the resolution of the spectrum we used and the accuracy of wavelength calibration. In this work, radial velocities of LAMOST-II medium resolution (R ~ 7500) spectra are measured for 1,594,956 spectra (each spectrum has two wavebands) through matching with templates. A set of RV standard stars are used to recalibrate the zero point of the measurement, and some reference sets with RVs derived from medium/high-resolution observations are used to evaluate the accuracy of the measurement. Comparing with reference sets, the accuracy of our measurement can get 0.0227 km s/1 with respect to radial velocities standard stars. The intrinsic precision is estimated with the multiple observations of single stars, which can achieve to 1.36 km s/1,1.08 km s/1, 0.91 km s/1 for the spectra at signal-to-noise levels of 10, 20, 50, respectively., published by ApJs. 13 pages, 13 figures

The technology of nail shooting was improved and used to study the transverse shape of the solidified shell during steel continuous casting. Three locations across the slab width (1/2, 1/4 and 1/8) were measured by nail shooting and which indicated a larger solidification coefficient and longer liquid core in the slab at higher casting speeds. The solidified shell across the slab width direction was non-uniform due to uneven secondary spray cooling. The point of final solidification at locations 1/8 and 1/4 was much longer than the position between the slab centre and location 1/4, leading to a long solidification end of >2 m, which is poor for the application of dynamic soft reduction. A mathematical model was developed to simulate the growth of the solidified shell and which was in good agreement with the measurements measured by nail shooting. Based on the measurements and simulations, the water spray pattern was improved, making the solidified shell more uniform. Dynamic soft reduction was the...

A model for an irreversible four-heat-source absorption refrigerator with continuous flow, which considers the irreversibilities resulting from thermal resistance and internal dissipations of the working fluid, is established. In this model, an absorption refrigerator is treated as a combined cycle system of an irreversible Carnot heat engine driving an irreversible Carnot refrigerator. Two parameters I he and I r are introduced to characterise the internal irreversibilities of the heat engine and refrigerator in the equivalent cycle system respectively. Under a given total heat conductance of the heat exchangers, the optimal relation between the cooling rate and coefficient of performance is derived, and the conditions for the optimal design of the system are determined. Then, this relation is used to deduce some new performance bounds. Moreover, the effects of the internal irreversibility parameters I he and I r on the optimal performance of the system are also investigated. The results...

Sandy deserts and desertified lands (SDDL) cover most of north-western China, and desertification is a severe environmental issue in this region. In this study, we classify SDDL into mobile, semi-mobile, semi-anchored, and anchored classes, and divide the corresponding severity of desertification into four levels: extremely severe, severe, moderate, and slight. Using SDDL databases derived from Landsat TM and ETM images in 1986 and 2000, we discuss the evolution of SDDL and the processes and causes of desertification. The desertified area increased by 16 101 km2 between 1986 and 2000, and most of the desertified land was classified as severely or extremely severely desertified. However, 3437 km2 of SDDL were also rehabilitated during this period. The area of SDDL increased in the Qinghai and Xinjiang regions, and in the western part of Inner Mongolia, but decreased in the Shaanxi, Gansu, and Ningxia regions. The causes of desertification differed among regions, and different measures to control desertification are proposed for the different regions.

In a cold roll forming process, the sheet is progressively formed into a three-dimensional surface. In order to reduce forming defects and trial production cost, computer simulation technology is employed in cold roll forming. Based on the updated Lagrange method in deformation mechanics, a theoretical model of elastic–plastic large deformation spline finite strip method is presented in this paper. The method has been employed to analyse the progressive roll forming process of the deformed strip, and the three dimensional displacement, strain, and stress fields between two stands during the multiple cold rolls forming process. The calculation results prove that the outer edge and the corner part of the deformed strip are submitted to larger deformation. The transverse deformation is principal, and the longitudinal deformation is small. This program, written in C language, can also be used to analyse other simple cross-sectional profiles.

Penicillin G (Pen-G) was hydrolyzed to 6-aminopenicillanic acid (6-APA) and phenylacetic acid (PAA) in a chromatographic reactor-separator using the mixture of immobilized Escherichia coli cells and a macroporous adsorbent as stationary phase and a phosphate buffer of pH 7.8 as eluant. Pen-G conversion of 98% was observed without adjustment of the eluant pH due to the effective separation of 6-APA from Pen-G and PAA. At a sample load of 600 mg Pen-G, the volume overload gave higher Pen-G conversion (86%) than the mass overload (68%), while their difference in product resolution (0.9 and 1.0, respectively) was insignificant.

Nanostructured ceria particles have been successfully synthesized by detonation method with emulsion explosives. The effects of mass content of Ce(NO3)3·6H2O in emulsion explosives on particle size of CeO2 were investigated. X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) were carried out to characterize as-synthesized powders. The ultraviolet absorption performance of nanostructured ceria was tested by ultraviolet spectrophotometer. The results indicated that the mass content of Ce(NO3)3·6H2O in emulsion explosives affected the particle size of ceria mostly. When the mass content of Ce(NO3)3·6H2O was 53.2%, the particle size of ceria was even and on the small side. The UV absorption performance of assynthesized nanostructured ceria was excellent, especially for ultraviolet B.

This article reports the mechanical properties and in vitro evaluation of a collagen scaffold fabricated using an indirect 3D printing technique. Collagen scaffolds, featuring predefined internal channels and capillary networks, were manufactured using phase change printing. It was observed that the collagen scaffolds featured internal channels and a hierarchical structure that varied over length scales of 10-400 microm. In vitro evaluation using hMSCs demonstrated that the resultant collagen based scaffolds have the ability to support hMSC cell attachment and proliferation; cells can migrate and survive deep within the structure of the scaffold. The cell numbers increased 2.4 times over 28 days in culture for the lysine treated scaffolds. The cells were spread along the collagen fibers to form a 3D structure and extracellular matrix was detected on the surface of the scaffolds after 4 weeks in culture. The crosslinking treatment enhanced the biostability and dynamic properties of the collagen scaffolds significantly.

This study applies the methodology and procedure of process capability to investigate a solid free-form fabrication technique as a manufacturing method to produce scaffold moulds for tissue engineering. The process capability Cp k and process performance Pp k of scaffold mould manufacture using a solid free-form fabrication technique has been analysed with respect to the dimension deviations. A solid free-form fabrication machine T66 was used to fabricate scaffold moulds in this study and is able to create features that ranged from 200 μm to 1000 μm. The analysis showed that the printing process under the normal cooling conditions of the printing chamber was in statistical control but gave low process capability indices, indicating that the process was ‘inadequate’ for production of ‘dimension-consistent’ scaffold moulds. The study demonstrates that, by lowering the temperature of the cooling conditions, the capability Cp k of the printing process can be improved (about threefold) sufficiently to ensure the consistent production of scaffold moulds with dimension characteristics within their specification limits.

Bamboo is a typical natural composite material, and its special structure and excellent properties provide important information for the biomimetic design of composites. To strengthen the fiber content of bamboo distributed in a gradient, a bimimetic nano-Al2O3 composite coating was designed and prepared on the surface of metal parts using a nanocomposite electrodeposition method. The optimal technology parameters were obtained, such as current density, PH value, nano-Al2O3 content in electrolyte, and style of stirring etc after the experiments. The microstructure of the biomimetic nanocomposite gradient coating was very dense, and the contents of nano-Al2O3 were distributed in the gradient. The microhardness of the composite coating changed from the surface to the inside in the gradient also. Moreover, the wetting angle between water and composite coating obviously increased and reached 97°at room temperature.

Through evolution over hundreds of millions of years, the natural biomaterials generally have superior microstructure and function to normal material. The surface layer of teeth is enamel, which is the hardest structure in the human body. Enamel as a kind of nanoceramic biomaterial; most of its physical and chemical characteristics are similar to normal ceramics. It is of high hardness and is particularly wear resistance. However, the gray cast iron is one of widely used materials. In the process of casting, surface blowholes and micro-pores, which can’t be seen by the naked eye, are formed in castings because of the solidification shrinkage of alloy and separation of gas dissolving in liquid alloy, which results in the poor property of materials. Therefore, the gray cast iron and nano-Al2O3 were chosen as the substrate and reinforcement in this paper, respectively. A laser cladding method was used to prepare biomimetic nanoceramic surface modification composite materials. The surface property of gray cast iron was largely improved. The process and the factors influencing laser cladding were analysed. The microstructure of the surface modification layer can be divided into a cladding layer, bonding layer and substrate layer, and the formation mechanism of each different layer was researched.

This letter presents a bionic study on Parnassius butterfly wings with a prominent ultraviolet (UV)-selective antireflection effect. An accurate SiO2 inverse replica of the nanostructure with a unique optical function from butterfly wings is prepared in multiscale by combining a sol-gel process and subsequent selective etching. It is found that the original nanostructures of biotemplate are well inherited and the excellent UV-antireflection function could be modulated by tunable parameters such as the replica spacing, width, distribution, and shape as well as formation.

Using first-principles calculations, effects of intrinsic stacking faults on the work function (WF) and surface energy of the () surface of fcc metals were investigated. A simple rule was summarized based on the calculated results. It was found that the WF of the metals of IA, IIA, IIIA, IIIB, IVB and VIIB groups decreased due to the intrinsic stacking faults, whereas Fe of IVB group was an exception; the WF of the metals of IVA, IB and VIII groups increased whereas Fe and Pt were two exceptions. However, for the concerned 28 metals, the corresponding surface energy of () decreased except Mn, Fe, Tc, Ru, Hf, Re and Os. The mechanism for such changes is further discussed.

The protective action of Glycyrrhiza flavonoids (GF), the major components in the radix of Glycyrrhiza, on carbon tetrachloride-induced hepatotoxicity was investigated. The carbon tetrachloride-induced increases of serum glutamic-pyruvic transaminase and lactate dehydrogenase were significantly inhibited by GF dose-dependently. Carbon tetrachloride-induced necrosis in mice were ameliorated by GF pretreatment. Concomitantly, the carbon tetrachloride-induced elevation of MDA in the liver was lowered by GF. GF neither reduced the activities of the two enzymes in normal mouse sera nor directly inhibited the activities of the two enzymes in the serum. These findings suggest that the anti-lipid peroxidation effect of GF was contributed to its protective action against carbon tetrachloride-induced hepatotoxicity.

Astragalus Polysaccharide (APS), an active component, was isolated from the radix of Astragalus membranaceus Bge var. mongholicus (Bge) Hsiao, and the effects of APS on E. coli endotoxin-induced liver damage were investigated in mice. The results showed that when mice were pretreated with APS (30, 60, 100 mg.kg-1.d-1 x 7d, ip), the survival rate of endotoxin intoxicated mice was increased the lowering of ATP levels and adenylate energy charge in mouse liver could be prevented. APS 100 mg.kg-1 could protect the mice from death on endotoxin (25 mg.kg-1) intoxication; and the level of ATP, the value of adenylate energy charge in the protected mouse liver were almost recovered to normal range. The effects of APS were shown to be dose-dependent. Concomitantly, the increase of MDA and decrease of GSH in mouse liver could be corrected by APS pretreatment. The results revealed that APS has an antioxidative action. An ultramicroscopic examination showed that the injury of the bio-membrane and the crest of mitochondria were ameliorated by APS pretreatment. These findings suggest that the protective effects of APS on E. coli endotoxin intoxicated mice may be due to its antioxidative action to protect the mitochondria bio-membrane, therefore, the adenylate metabolism is improved in mouse liver.

The antiperoxidant action of berbamine (Ber) was demonstrated by colorimetric estimation of malondialdehyde (MDA) formation, and the scavenging effect of Ber on O2- was investigated by chemiluminescence method and ESR-spin trapping technique. Ber 11-100 mumol/L remarkably inhibited MDA formation induced by incubating mice liver homogenate at 37 degrees C with vibration for 1 h. Ber 1-100 mumol/L and 0.2-0.6 mmol/L effectively scavenged O2- in alkaline DMSO and xanthine/xanthine oxidase systems respectively. The results show that Ber is an antioxidant.

The scavenging effects of sodium ferulate (SF) and glycyrrhetic acid (GA) on oxygen free radicals were studied by using spin trapping technique and chemiluminescence (CL) methods. SF 0.3 mmol/L and GA 0.3 mmol/L effectively scavenged oxygen free radicals produced by phorbol myristate acetate (PMA)-stimulated polymorphonuclear leukocytes (PMN), but had no effect on the oxygen consumption by PMN, measured with spin probe oxymetry. In 3 cell-free oxygen free radical generating systems, both SF and GA showed a remarkably scavenging effects on O2- and OH.. SF 30 mumol/L and GA 30 mumol/L prominently inhibited the CL response of PMA-stimulated PMN. The results demonstrated that SF and GA are oxygen free radical scavengers.

The antiperoxidant activity of glycyrrhiza flavonoid (FG) was studied by using colorimetric estimation of lipid peroxide (MDA) formation. The scavenging effects of FG on O2-. and OH. was investigated by using chemiluminescence method and spin trapping technique in different systems. The results were as follows: FG 2.8-25 micrograms/ml effectively inhibited MDA formation induced by incubating mice liver homogenate at 37 degrees C for 1 h; FG 0.265-26.5 micrograms/ml or 2.58-258 micrograms/ml was shown to markedly scavenge O2-. in alkaline/DMSO or xanthine/xanthine oxidase systems, respectively in a concentration-dependent manner. FG 144 micrograms/ml or 258 micrograms/ml also significantly scavenged the active oxygen radicals produced by PMN stimulation with PMA or OH. produced in Fenton's reaction respectively. The results suggest that FG may be used as an antioxidant.