HnRNP K and PDI marked response to chemotherapy to human colorectal cancer cells

5‐Fluorouracil has been the chemotherapy agent of first‐choice for colorectal cancer for many years, but since there are no proven predictors of a patient's response to therapy, all patients receive similar treatment. Consequently, identification of biomarkers for therapeutic effect is crucial for the development of novel therapeutic strategies. Two human colorectal cancer cell lines of different metastatic potential (LoVo and SW480) were studied. IC50 of 5‐FU for both cell lines were measured by 3‐(4,5‐dimethy‐lthiazol‐2‐yl)‐2,5‐diphenyltetrazolium assay and validated by cell cycle analysis. Then the cell lines were treated with 5‐FU at IC50 concentration and protein was extracted for 2‐DE. Differential protein spots were examined by MALDI‐TOF/TOF MS. The expression levels of the different proteins were further confirmed by Western blot and immunofluorescence analyses. Eleven proteins were identified. Expression of heterogeneous nuclear ribonucleoprotein K (hnRNP K) in LoVo cells was higher than in SW480 cells, while protein disulfide isomerase (PDI) displayed the opposite trend. After treatment with 5‐FU, the expression of hnRNP K in LoVo decreased more significantly than in SW480, while PDI in SW480 increased more significantly than in LoVo cells. Conclusion: hnRNP K and PDI in the two cell lines have different expression characteristics. The sensitivity to 5‐FU is not consistent in tumor progression. It may assist in development of novel treatment strategies for colorectal cancer metastasis.     

强流脉冲离子束辐照对不锈钢耐腐蚀性能的影响

利用强流脉冲离子束（HIPIB）对316L不锈钢进行了表面辐照处理,研究了HIPIB辐照对其在0.5mol/L H2SO4溶液中电化学腐蚀性能的影响。极化曲线测量结果表明,HIPIB辐照能够显著提高316L的抗腐蚀性能,自腐蚀电流对辐照次数的依赖性与自腐蚀电位相比明显较强。采用扫描电子显微镜（SEM）、X射线衍射（XRD）和电子探针（EPMA）分析辐照后试样表面形貌、表面层相结构和元素分布的变化。结果表明：HIPIB辐照使试样表面光滑化,表面层产生择优取向,且发生了杂质元素的选择性烧蚀,是316L不锈钢耐电化学腐蚀性能得以提高的主要原因。     

L波段相对论速调管放大器研究

介绍了L 波段强流相对论速调管放大器高频系统的设计, 强流相对论空心电子束的产生、传输、调制及微波输出等的初步实验结果。在直线感应加速器上, 利用无箔空心石墨阴极, 引出了电压约500kV、电流4. 5kA、直径54. 5mm、厚度4. 5mm 的空心电子束, 经过三腔放大后, 得到了536MW 的微波峰值功率, 效率21% , 增益30dB。     

相对论强流长脉冲速调管放大器

为了研制高功率长脉冲速调管放大器,对其输入腔进行了3维粒子模拟研究。建立了S波段速调管放大器输入腔开放腔的3维模型,计算了开放腔的谐振频率和有载Q值。将束压束流从原来的600 kV,5.4 kA提高到837 kV,12.48 kA,实现了长脉冲100 ns的稳定运行,调制束流与实验结果一致。在结构不变的情况下,将束压束流提高到900 kV,16 kA时出现了模式竞争,只能稳定运行到50 ns。为了克服模式竞争,将耦合孔改为对称的双耦合孔后,输入腔系统可以稳定运行到100 ns。     

掺镱光纤放大器的啁啾脉冲失谐放大特性

研究了掺镱光纤放大器对中心频率为1 053nm的啁啾脉冲放大特性,发现针对高斯或超高斯脉冲,采用合适的带宽及入射光强能够使增益饱和和失谐放大相互消弱,从而得到一个良好的放大脉冲形状。计算了掺镱光纤放大器失谐放大带来的相位调制,发现对压缩质量影响较小。     

飞秒激光诱导水光学击穿阈值

为了研究飞秒激光诱导水光学击穿阈值随激光脉冲参数的变化关系,采用四阶Runge-Kutta方法对飞秒激光诱导水光学击穿的椭球体模型进行了不同脉宽（40~540 fs）、波长(400~1 200 nm)和光斑尺寸（0~200 μm）下的数值模拟。通过控制变量法得出阈值光强与这些激光脉冲参数的关系曲线图,据此定性分析了阈值光强与激光脉冲参数的变化特征趋势。应用光强与功率、能量、辐照曝光量和电场强度之间的关系,得到了它们随激光脉冲参数脉宽、波长和光斑尺寸的动态关系,这为进一步研究飞秒激光与水和含水介质的相互作用提供了理论依据。     

衬底温度对PLD制备的Mo薄膜结构及表面形貌的影响

运用脉冲激光沉积(PLD)技术在Si(100)基片上沉积了金属Mo薄膜。在激光重复频率2 Hz,能量密度5.2 J/cm2,本底真空10－6 Pa的条件下,研究Mo薄膜的结构和表面形貌,讨论了衬底温度对薄膜形貌与结构的影响。原子力显微镜(AFM)图像和X射线小角衍射(XRD)分析表明,薄膜表面平整、光滑,均方根粗糙度小于2 nm。沉积温度对Mo薄膜结构和表面形貌影响较大,在373~573 K范围内随着温度升高,薄膜粗糙度变小,结晶程度变好。     

高功率高重频U型腔激光器的仿真与实验研究

为了得到结构紧凑的高功率、高重复频率固体激光器,设计了“U”型光学谐振腔,并利用LAS-CAD软件分析了激光晶体的热效应和激光输出特性。根据仿真结果进行了具体实验,最终得到了腔长400 mm的紧凑型固体激光器。在重复频率为100 kHz,泵浦功率为60 W时,输出功率达到21.6 W,光-光转换效率为36%,斜率效率为39.9%。     

CSNS\RCS引出系统快脉冲冲击磁铁样机的设计

设计了中国散裂中子源(CSNS)快循环同步加速器(RCS)引出系统快脉冲冲击磁铁样机。为降低磁铁和其电源的研制难度,保证运行的可靠性,决定采用美国散裂中子源(SNS)的Single-turn结构。根据磁铁的设计指标,给出了磁铁设计要求铁芯材料选择方法、整体的结构设计以及如何对磁铁进行定位和准直,并采用Opera程序进行模拟计算,结果表明：当铁芯长度为220 mm时,磁有效长度大约为302 mm;磁感应密度最大的地方在4个内角上,约为0.215 T;在133 mm×200 mm的平面范围内,磁场均匀性优于±0.8%。理论分析和Opera程序模拟均验证了磁铁结构方案的可行性。     

Global Solutions for Incompressible Viscoelastic Fluids

We prove the existence of both local and global smooth solutions to the Cauchy problem in the whole space and the periodic problem in the n-dimensional torus for the incompressible viscoelastic system of Oldroyd-B type in the case of near- equilibrium initial data. The results hold in both two- and three-dimensional spaces. The results and methods presented in this paper are also valid for a wide range of elastic complex fluids, such as magnetohydrodynamics, liquid crystals, and mixture problems.