摘要：In this paper, thermal characteristics of the high-power LED spot lamp are reported. The emphasis is placed upon optimizing design of the heat sink of LED spot lamp using the optimization module and the orthogonal-experiment method. Results demonstrate that the weight of the heat sink is decreased to 46.1% of that for the initial structure, and the influence of each factor on junction temperature and weight of the heat sink is acquired by range analysis. Finally, the influence of ambient temperature and natural convection coefficient on the LED maximum temperature is analyzed. The results and the optimizing methodology are of great importance to the thermal design of LED lamps.

摘要：In this paper, graphite-like carbon （GLC） films with Cr buffer layer were fabricated by DC magnetron sputtering technique with the thickness ratio of Cr to GLC films varying from 1：2 to 1：20. The effect of Cr]GLC modulation ratio on microstructure, mechanical and tribological properties in artificial seawater was mainly investigated by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, nano-indenter and a reciprocating sliding tribo-meter. The propagation of defects plays an important role in the evolution of delamination, which is critical to wear failure of GLC films in artificial seawa- ter. Designing the proper multilayer structure could inhibit the defects propagation and thus protect the basis material. The multilayer Cr/GLC film with optimized ratio of 1：3 demonstrates a low average friction coefficient of 0.08 ± 0.006 and wear rate of （2.3 ± 0.3） × 10^-8 mm3/（N m） in artificial seawater, respectively.

摘要：The high incidence of cardiovascular disease has led to significant demand for synthetic vascular grafts in clinical ***-proliferation drugs are usually loaded into devices to achieve desirable anti-thrombosis effects after ***,the non-selectiveness of these conventional drugs can lead to the failure of blood vessel reconstruction,leading to potential complications in the long *** address this issue,an asymmetric membrane was constructed through electro-spinning *** bilayer membrane loaded and effectively released nitric oxide(NO),as hoped,from only one *** to the short diffusion distance of NO,it exerted negligible effects on the other side of the membrane,thus allowing selective regulation of different cells on both *** released NO boosted the growth of endothelial cells(ECs)over smooth muscle cells(SMCs)-while on the side where NO was absent,SMCs grew into *** overall structure resembled a native blood vessel,with confluent ECs as the inner layer and layers of SMCs to support *** addition,the membrane preserved the normal function of ECs,and at the same time did not exacerbate inflammatory *** preparing this material type that regulates cell behavior differentially,we describe a new method for its application in the cardiovascular field such as for artificial blood vessels.

摘要：Disposable blood collection needles become severely intertwined and hooked during stacking, and thus individually feeding disposable blood collection needles during mechanical packaging is di cult. Based on the physical characteristics of the blood collection needles during the stacking state, this study designed an automatic tidying and sorting mechanism by combining compound vibration, sorting, and conveying. During the feeding process, the compound vibration-type material-tidying mechanism tidies 20-30 blood collection needles first;then, the material sorting and conveying mechanism transports the tidied blood collection needles individually. The orthogonal testing of the automatic material tidying process shows that various experimental factors are ranked by the significance level of the e ect on the tidying process and the significance ranking is as follows: vertical vibration frequency > horizontal amplitude > vertical amplitude > horizontal vibration frequency. Experiments were performed after analyzing the optimal combination. The results demonstrate that when the horizontal vibration frequency is 1.7 Hz, the horizontal amplitude is 150 mm, vertical vibration frequency is 1.3 Hz, vertical amplitude is 30 mm, and material length after tidying is 265 mm. The automatic sorting and conveying experiment shows the e ect of various experimental factors on the feed rate of the material, where the significance level of the e ect is ranked as follows: vibration frequency > material quantity > channel dip angle. The experimental results show that when the number of materials is 25, the channel dip angle is 12°, and vibration frequency is 52.5 Hz. The material delivery e ciency reaches 0.51 s/root, meeting the requirement of five channels for 80000 root/day feeding e ciency. The study can provide reference for the realization of automatic feeding of large aspect ratio flexible materials in similar stacking state.

摘要：The advancement in the materials manufacturing at micrometer and nanometer scales has already enabled numerous applications in electronics, optics, chemistry, biology and medicine. Biomedical devices carrying micro-/nanostructures are currently being widely used in drug delivery, drug release, biosensing and therapy. New clinical methods for disease diagnosis and treatments are being developed enabled by nanotech no logy. One-dimensional (ID) structures are playi ng an importa nt role in the direct drug delivery both in vivo and ex vivo among various micro-/nanostructures. Here, in this paper, we reviewed recent progresses made on next-generation intradermal and intracellular delivery strategies and applications with focus on ID microstructure-based approaches.

摘要：The highest similarity degree of static characteristics including both horizontal and vertical restoring force-displacement characteristics of total mooring system, as well as the tension-displacement characteristics of the representative single mooring line between the truncated and full depth system are obtained by annealing simulation algorithm for hybrid discrete variables （ASFHDV, in short）. A“baton” optimization approach is proposed by utilizing ASFHDV. After each baton of optimization, if a few dimensional variables reach the upper or lower limit, the boundary of certain dimensional variables shall be expanded. In consideration of the experimental requirements, the length of the upper mooring line should not be smaller than 8 m, and the diameter of the anchor chain on the bottom should be larger than 0.03 m. A 100000 t turret mooring FPSO in the water depth of 304 m, with the truncated water depth being 76 m, is taken as an example of equivalent water depth truncated mooring system optimal design and calculation, and is performed to obtain the conformation parameters of the truncated mooring system. The numerical results indicate that the present truncated mooring system design is successful and effective.

摘要：Three-dimensional （3D） printing is a novel promising technology based on 3D imaging and layer-by-layer additive fabrication. It has a profound influence on all aspects of our lives and is playing an increasing important role in many areas including engineering, manufacturing, art, education and medicine. ＂3D bioprinting＂ has been put forward with the technical progress in 3D printing and might be a possible way to solve the serious problem of human organ shortage in tissue engineering and regenerative medicine. Many research groups flung them into this area and have already made some gratifying achievements. However, it is a long way to fabricate a live organ. Many elements lead to the limitation of 3D bioprinting. This review introduces the background and development history of 3D bioprinting, compares different approaches of 3D bioprinting and illustrates the key factors of the printing process. Meanwhile, this review also points out existing challenges of 3D bioprinting and has a great prospect. Some points proposed in this review might be served as reference for the research of this field.

摘要：Previous studies have suggested that the transforming growth factor-β receptor ALK5 is crucial for articular chondrogenesis by bone marrow mesenchymal stem cells. Here, the wild-type ALK5 plasmids were mutated by overlapping extended PCR and transfected into bone marrow mesenchymal stem cells. The knee joint osteoarthritis mouse model was constructed by cutting oft＂ the anterior cruciate ligament and divided into three groups： saline group, bone marrow mesenchymal stem cells and ALK5-transfected bone marrow mesenchymal stem cells group. HE staining showed that the articular cartilage lesions were more serious of saline group compared with that of mesenchymal stem cell group, and this trend was more pronounced as time goes on. Immunohistochemical staining showed that although the expression level of type II collagen in all three groups down-regulated gradually upon time, its expression in ALK5-transfected bone marrow mesenchymal stem cells group was significantly enhanced compared with the other two groups. Micro-CT also suggested that ALK5 transfection of mouse bone marrow mesenchymal stem cells would promote repairing the knee cartilage lesions with arthritis of the mice. Although the osteoarthritis mechanism underlying a variety of factors work together, and the appropriate proportion of ALKS/ALK1 was also emphasized for the treatment of osteoarthritis. This work therefore demonstrated that ALK5 transfection of bone marrow mesenchymal stem cells could be a promising stem cell therapy for repair of cartilage lesions.

摘要：The Yangtze River Delta characterized by a dense population and a rapidly developing economy is highly vulnerable to sea-level rise. The data from the China Oceanic Information Network and the zhejiang Provincial Hydrology Bureau are used to analyze sea-level rise. The rate of sea-level rise in the delta was 2.4 mm per year in 1981-2015. The annual sea-level at Daishan, Dinghai, and Dongtou stations in the south wing of the delta were 4.3, 3.1, and 5 mm per year respectively over the same period. The 10-year averaged results at each station also indicate a perceptible trend of sea-level rise. Sea-level rise is contributed to a larger proportion of intensified erosion, ranging from 3% to 14% in the delta. Meanwhile, the 100-year return period of tidal level has decreased to the 50-year rank at Dongtou and Dinghai stations. Moreover, the arrival time of tidal bores at Yanguan is 4 min earlier under sea-level rise of 0.145 m than that of 0 m. The height of tidal bores and the velocities at the surface and bottom layers have an increase under sea-level rise. The maximum increases of high and low tide levels are 0.122 m and 0.016 m while the maximum increases of the velocities at the surface and bottom layers are 0.07 m s^- 1 and 0.05 m s ^-1, respectively. Sea-level rise will bring about the damage of seawall, thus the design standard of constructing seawalls should adopt a higher level to minimize the associated risks in the Yangtze River Delta and its south wing.

摘要：The advancement in the micro-/nanofabrication techniques has greatly facilitated the development of micromotors.A variety of micromotors have been invented with powerful functions,which have attracted a broad range of interests from chemistry, physics,mechanics,biology and *** this paper,we reviewed recent progress in micromotors and highlighted representative *** mechanisms of micromotors by internal and external energy sources were *** described general fabrication strategies of the popular micromotors (wire,tubular,helical and Janus)including bottom-up and top-down *** the application section,we primarily focused on the biological applications,such as biological cargo delivery, biosensing and *** last,we discussed the current challenges and provided future prospects.