摘要：Biomaterial scaffolds play an important role in maintaining the viability and biological functions of highly metabolic hepatocytes in liver tissue engineering. One of the major challenges involves building a complex microchannel network inside three-dimensional （3D） scaffolds for efficient mass transportation. Here we presented a biomimetic strategy to generate a mi- crochannel network within porous biomaterial scaffolds by mimicking the vascular tree of rat liver. The typical parameters of the blood vessels were incorporated into the biomimetic design of the microchannel network such as branching angle and diameter. Silk fibroin-gelatin scaffolds with biomimetic vascular tree were fabricated by combining micromolding, freeze drying and 3D rolling techniques. The relationship between the micro-channeled design and flow pattern was revealed by a flow experiment, which indicated that the scaffolds with biomimetic vascular tree exhibited unique capability in improving mass transportation inside the 3D scaffold. The 3D scaffolds, preseeded with primary hepatocytes, were dynamically cultured in a bioreactor system. The results confirmed that the pre-designed biomimetic microchannel network facilitated the generation and expansion of hepatocytes.

摘要：Stiffened plates or shells are widely used in engineering structures as primary or secondary load-bearing *** to design the layout and sizes of the stiffeners is of great significance for structural *** this work,a new topology optimization method for simultaneously optimizing the layout and cross-section topology of the stiffeners is developed to solve this *** stilfeners and base plates are modeled by the beam and shell elements,respectively,significantly reducing the computational *** Giavotto beam theory,instead of the widely employed Euler or Timoshenko beam theory,is applied to model the stiffeners for considering the warping deformation in evaluating the section stiffness of the beam.A multi-scale topology optimization model is established by simultaneously optimizing the layout of the beam and the topology of the *** design space is significantly expanded by optimizing these two types of design *** numerical examples are applied to illustrate the validity and effectiveness of the proposed *** results show that the proposed two-scale optimization approach can generate better designs than the single-scale method.

摘要：A novel series of eight SMS and sPLA2 dual inhibitors containing indole and a-amino cyanide fragments of different length and substitution position was synthesized and evaluated by three different in vitro assays. Biological evaluation showed that all compounds provided inhibitory effects against SMS （about 50% inhibition at 100 μmol/L） and sPLA2 （14-32 μmol/L）. All the compounds had the SMS activity better than the positive control compound D609 in SMS2 homogenate, with compounds 5b and fie ideal for liver homogenate and SMS2 high expression cell homogenate, respectively.

摘要：Micron/nano scale topographic modification has been a significant focus of interest in current titanium(Ti)surface ***,the influence of micron/nano structured surface on cell or bacterium behavior on the Ti implant has rarely been systematically ***,except for popular microgrooves,little work has been carried out on the reaction of cells to the bionic *** this study,several micro-pillars mimicking cell morphology were prepared on Ti surfaces by lithography and contact printing(ICP)method,and they were further decorated with nanotube arrays by anodization *** surface modifications remarkablly increased the surface roughness of pristine Ti surface from 91.17 nm±5.57 nm to be more than 1000 nm,and reduced their water contact angles from 68.3°±0.7°to be 16.9°±2.4°.Then,the effects of these hierarchical micron/nano scale patterns on the behaviors of MG63 osteoblasts,L929 fibroblasts,SCC epithelial cells and *** were studied,aiming to evaluate their performance in osseointegration,gingival epithelial sealing and antibacterial *** an innovative scoring strategy,our findings showed that square micro-pillars with 6μm width and 2μm height combined with 85 nm diameter nanotubes was suitable for implant neck design,while square micro-pillars with 3μm width and 3.6μm height combined with 55 nm diameter nanotubes was the best for implant body *** study reveals the synergistic effect of the hierarchical micron/nano scale patterns on MG63 osteoblasts,L929 fibroblasts,SCC epithelial cells and *** *** provides insight into the design of biomedical implant surfaces.

摘要：Background Chronic obstructive pulmonary disease(COPD)is a severe public health *** smoke(CS)is a risk factor for COPD and lung *** underlying molecular mechanisms of CS-induced malignant transformation of bronchial epithelial cells remain *** this study,we describe a lung-on-a-chip to explore the possible mechanistic link between cigarette smoke extract(CSE)-associated COPD and lung *** An in vitro lung-on-a-chip model was used to simulate pulmonary epithelial cells and vascular endothelial cells with *** levels of IL-6 and TNF-αwere tested as indicators of inflammation using an enzyme-linked immune sorbent *** junction complex mRNA expression was detected with qRT-PCR as the index of epithelial-to-mesenchymal transition(EMT).The effects of CSE on the phosphorylation of signal transduction and transcriptional activator 3(STAT3)were detected by Western *** cytometry was performed to investigate the effects of this proto-oncogene on cell cycle *** Inflammation caused by CSE was achieved in a lung-on-a-chip model with a mimetic *** exposure induced the degradation of intercellular connections and triggered the EMT *** exposure also activated the phosphorylation of proto-oncogene STAT3,while these effects were inhibited with *** CSE exposure in the lung-on-a-chip model caused activation of STAT3 in epithelial cells and endothelial ***0152,an inhibitor of activated STAT3,could be a potential treatment for CS-associated COPD and lung cancer.

摘要：This study develops a multivariate eco-hydrological risk-assessment framework based on the multivari-ate copula method in order to evaluate the occurrence of extreme eco-hydrological events for the Xiangxi River within the Three Gorges Reservoir （TGR） area in china. Parameter uncertainties in marginal distri-butions and dependence structure are quantified by a Markov chain Monte Carlo （MCMC） algorithm. Uncertainties in the joint return periods are evaluated based on the posterior distributions. The proba- bilistic features of bivariate and multivariate hydrological risk are also characterized. The results show that the obtained predictive intervals bracketed the observations well, especially for flood duration. The uncertainty for the joint return period in ＂AND＂ case increases with an increase in the return period for univariate flood variables. Furthermore, a low design discharge and high service time may lead to high bivariate hydrological risk with great uncertainty.

摘要：A compact multi-throttle aerostatic guideway is the preferred structure for high precision and acceleration motion in the variable-slit system(VS)of *** presence of microstructure,such as recesses and grooves,on the guideway working surface has been found to improve the loading ***,the effects on the guideway performance of changing the microstructure on the micron level are not yet *** mesh adaptation method,which was proposed by the authors,is employed in this paper to quantitatively study the influences of four microstructure *** effect of tuning these parameters on the loading performance is *** level of impact determines the proposed design process of the *** characteristic feature of the proposed design process is that the working points of carrying capacity,stiffness,and rotational stiffness are unified under twoway adjusting by means of recess *** to the proposed design process and tuning method,the restriction of supply pressure is lifted to a certain extent and the mutual tradeoff among the loading performances is *** experimental results show that the rotational stiffness of the designed guideway,based on the tuned parameters,reached 2.14×10^(4) Nmrad1 and increased by 69.8%.In a scanning test of the applied VS on argon fluoride laser(ArF)photolithography,the average scanning acceleration reached 67.5 m·s^(-2),meeting the design specification.

摘要：In this study,a copper ferrocyanide/silica/polyvinylidene fluoride(CuFC/SiO2/PVDF)hollow-fiber composite membrane was successfully synthesized through a facile and effective crosslinking *** PVDF hollow-fiber membrane with embedded SiO2 was used to fix the dispersion of CuFC nanoparticles for cesium(Cs)*** surface morphology and chemical composition of the composite membrane were analyzed using scanning electron microscopy and X-ray photoelectron spectroscopy(XPS).The composite membrane showed a high Cs rejection rate and membrane flux at the three layers of CuFC and 0.5%SiO2,and its Cs rejection rate was not affected by variation in the pH(pH=4–10).The modified membrane could be effectively regenerated many times using ammonium nitrate(NH4NO3).The Cs selectivity performance was verified by an efficient Cs rejection rate(76.25%and 88.67%in 8 h)in a solution of 100 lg L 1 of Cs with 1 mmol L 1 of competing cations(K+and Na+).The CuFC/SiO2/PVDF hollowfiber composite membrane showed a particularly superior removal performance(greater than 90%)in natural surface water and simulated water with a low Cs ***,the CuFC/SiO2/PVDF hollow-fiber composite membrane can be used directly in engineering applications for the remediation of radioactive Cs-contaminated water.

摘要：An energy-storage system comprised of lithium-ion battery modules is considered to be a core component of new energy vehicles,as it provides the main power source for the transmission ***,manufacturing defects in battery modules lead to variations in performance among the cells used in series or parallel *** variation results in incomplete charge and discharge of batteries and non-uniform temperature distribution,which further lead to reduction of cycle life and battery capacity over *** solve this problem,this work uses experimental and numerical methods to conduct a comprehensive investigation on the clustering of battery cells with similar performance in order to produce a battery module with improved electrochemical *** were first performed by dismantling battery modules for the measurement of performance *** kmeans clustering and support vector clustering(SVC)algorithms were then employed to produce battery modules composed of 12 cells *** verification of the results obtained from the clustering analysis was performed by measuring the temperature rise in the cells over a certain period,while air cooling was *** was found that the SVC-clustered battery module in Category 3 exhibited the best performance,with a maximum observed temperature of 32℃.By contrast,the maximum observed temperatures of the other battery modules were higher,at 40℃for Category 1(manufacturer),36℃for Category 2(manufacturer),and 35℃for Category 4(k-means-clustered battery module).

摘要：轮式发射系统行驶动力学建模与仿真是其动力学性能和试验设计的前提和基础,日益提高的轮式发射系统动态性能迫切需要一种快速高效的大型多体系统动力学计算方法。本文采用多体系统传递矩阵法建立了轮式发射系统的动力学模型,给出了相应的拓扑图和动力学方程,此外,通过快速傅里叶逆变换重构了平行车轮的路面不平度,结合蒙特卡罗方法对随机路面激励下轮式发射系统的动力学特性进行了模拟和讨论分析结果表明,随着路面不平度级别和行驶速度的增加,轮式发射系统的振动加速度幅值越大,在正常车速下,路面激励对车体的影响远大于车速。模态试验和行驶试验验证了动力学建模和仿真的正确性本文可拓展到其他包含概率不确定性的多体系统动力学建模和分析.