图的有特殊性质的k-因子和半-k-因子

设 k≥ 1是一个整数 ,G是一个 2 -边连通图 ,U是 V( G)的子集 .设 F是 G的支撑子图 ,使得对所有 x∈ V( G) - U,有 deg F( x) =k,若对所有 x∈ U,有 deg F( x)≥ k,则 F称为带缺损 U的上限半 - k-因子 ;若对所有 x∈U,有 deg F( x)≤ k,则 F称为带缺损 U的下限半 - k-因子 .本文证明了若 k| V( G) |是偶数 ,| V( G) |≥ k+ 2 ,对 V( G)的任一基数为 k+ 2的子集 U,如果对任意 e∈ E( G) ,G都有一个带缺损 U的上限半 - k-因子含 e,则 G是 k-覆盖的 ;若 k≥ 2是一个偶数 ,| V( G) | >2 k+ 4 ,对V( G)的任一基数为 k+ 3的子集 U,如果对任意 e∈E( G) ,G有一个带缺损 U的上限半 - k-因子含e,则 G是 k-覆盖的 ;还证明了若 k| V( G) |是偶数 ,| V( G) |≥k+ 4 ,对 V( G)的任一基数为 3的子集U,如果对任意 e∈E( G) ,G都有一个带缺损 U的下限半 - k-因子含 e,则 G是 k-覆盖的 .

半乳糖凝集素-3在大鼠肝纤维化组织中的表达及意义

目的研究半乳糖凝集素-3(galectin-3,Gal-3)、转化生长因子β1(transforming growth factor beta-1,TGF-β1)、a-平滑肌肌动蛋白(a-smooth muscle actin,a-SMA)在肝纤维化大鼠模型中的动态表达及意义。方法雄性SD大鼠随机分为健康对照组6只,肝纤维化模型组24只,采用二甲基亚硝胺(DMN)腹腔注射制备肝纤维化模型。分别在造模后2、4、6、8周门静脉采血检测血清ALT、AST、Alb,采用HE及Masson染色观察肝组织学变化,反转录聚合酶链反应(RT-PCR)检测不同时间点肝脏galectin-3 mRNA的表达。结果正常肝组织中有galectin-3低表达,2周即升高,4周达高峰,6周下降,差异有统计学意义(P<0.05)。相关性分析显示,galectin-3水平与TGF-β1、a-SMA呈正相关(r=0.882～0.963,P<0.01)。结论 Galectin-3可能与肝纤维化的发生发展过程密切相关。

鲜鱼腥草挥发油对慢性肺损伤大鼠半胱氨酸-半胱氨酸趋化因子受体2表达的影响

目的观察鲜鱼腥草挥发油减轻慢性肺损伤及降低趋化因子受体[半胱氨酸-半胱氨酸趋化因子受体2(CCR2)]高表达的作用。方法取SD大鼠,气管滴入脂多糖(LPS)诱发慢性肺损伤模型(模型组))。模型组大鼠给予不同剂量鲜鱼腥草挥发油(给药组;再分为鲜血腥草挥发油高、中、低剂量组)。各组大鼠处死后进行其支气管肺泡灌洗,取其支气管肺泡灌洗液(BALF)离心后沉淀,行WBC计数和WBC分类。取其左肺石蜡切片常规处理,行HE染色、阿尔辛蓝-过碘酸雪夫染色,分析大鼠炎症程度和杯状细胞化生。免疫组织化学染色检测其CCR2的表达。结果 1.模型组大鼠BALF中WBC总数和中性粒细胞数明显高于正常组,肺组织呈不同程度、不同数量的支气管、细支气管慢性炎症。2.经不同剂量鲜鱼腥草挥发油灌胃后能减少WBC总数及中性粒细胞数,降低炎症程度;尤其是鲜鱼腥草挥发油高剂量组。3.给药组大鼠肺泡内CCR2阳性染色区域减少,染色程度减轻;通过图像分析,给药组大鼠肺组织中CCR2的表达较模型组显著降低。结论鲜鱼腥草挥发油可减轻LPS引起的大鼠慢性肺损伤,并能抑制肺泡内CCR2的高表达。

Reduction of Dimerization Tendency Due to the Decrease in Hybridization Index by Inclusion of 4s and 4p Semicore States as Valence States in Mo_(n)(n=2-18)Clusters:A First-Principles Study

Owing to the unique structural,electronic,and physico-chemical properties,molybdenum clusters are expected to play an important role in future nanotechnologies.However,their ground states are still under debate.In this study,the crystal structure analysis by particle swarm optimization(CALYPSO)approach is used for the global minimum search,which is followed by first-principles calculations,to detect an obvious dimerization tendency in Mo_(n)(n=2-18)clusters when the 4s and 4p semicore states are not regarded as the valence states.Further,the clusters with even number of atoms are usually magic clusters with high stability.However,after including the4 s and 4 p electrons as valence electrons,the dimerization tendency exhibits a drastic reduction because the average hybridization indices H_(sp),H_(sd),and H_(pd) are reduced significantly.Overall,this work reports new ground states of Mo_(n)(n=11,14,15)clusters and proves that semicore states are essential for Mo_(n) clusters.

Silence of HIN-1 expression through methylation of its gene promoter in gastric cancer

AIM: To clarify the role of high in normal-1 (HIN-1) gene promoter methylation during gastric cancer development. METHODS: Gastric cancer cell lines and tissue specimens were analyzed for expression of HIN-1 mRNA and protein using the semi-quantitative reverse transcription polymerase chain reaction and immunohistochemistry. The methylation of the HIN-1 gene promoter was detected in gastric carcinoma cells and tissues using methylation-specific polymerase chain reaction. The 3-(4,5-dimethylthiazol-2yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium cell viability assay and flow cytometry were used to assess the changes in behaviors of gastric cancer cells with or without 5-aza-2’-deoxycytidine treatment. RESULTS: HIN-1 was not expressed in 4 of 5 gastric cancer cell lines. The demethylation reagent 5-aza-2’-deoxycytidine was able to induce or upregulate HIN-1 expression in gastric cancer cell lines, which is associated with reduction of tumor cell viability. Furthermore, methylation of the HIN-1 gene promoter was shown in 57.8% (26/45) of the primary gastric cancer and 42.1% (17/38) of adjacent tissue samples, but was not shown in normal gastric mucosa (0/10). From the clinicopathological data of the patients, methylation of the HIN-1 gene promoter was found to be associated with tumor differentiation (P = 0.000). CONCLUSION: High methylation of HIN-1 gene promoter results in silence of HIN-1 expression in gastric cancer. 5-aza-2’-deoxycytidine reverses HIN-1 methylation and reduces viability of gastric cancer cells.

The Impact Heme Oxygenase -1 on the Regulating Factors of Hepatoma Cells＇ Cell Cycle

It aims to analyze the impact heme oxygenase -1 （heme oxygenase 1, HO-1） on regulating factors of human hepatoma cell HepG2＇s cell cycle, through constructing recombinant vector of pcDNA3.1 containing wild-type and mutant HO-1 gene （＋）-wtHO-1 and pcDNA3.1 （＋）-mHO-1G143H. By using the method of liposome-mediated, the recombinant vector was transfected hepatoma cell line HepG2. And the transfected one with empty vector was treated as a control group. By the selection of G418, stable expression of wild-type and mutant HO-1 in HepG2 liver cancer cell lines were established. Use the blot of semi-quantitative RT-PCR and Western to test transfected cell lines expressing levels of riO-1 mRNA and protein. As HO-1 expression in stably transfected cell lines altered, we use Western blot to test transfected cell lines P21, P27 protein expression levels. As result shows, we got 1 HO-over-expression of wild-type and mutant in HepG2 cells; wild- type and mutant＇s over expression of HO-1 can induce the expression of tumor suppressor genes p21 and p27.we got the conclusion that HO-l＇s over-expression of tumor suppressor genes p21 and p27 is unrelated to the expression of heme decomposition products. HO-1 may regulate the expression of p21 and p27 through other mechanisms.

The molecular mechanisms of Yang Wei Kang Liu powder on anticancer and reducing chemotherapy side-effect in combination with chemotherapy

Objective:We studied the molecular mechanisms of Yang Wei Kang Liu Power(YWKL,traditional Chinese medicine for nourishing stomach and anticancer) on anticancer and reducing chemotherapy side-effect in combination with chemotherapy.Methods:615 pre-cancer mouse model of YWKL for 10 days and CTX 1 time,semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR) to detect bone marrow granulocyte-macrophage colony-stimulating factor(GM-CSF) gene and cancer proto-oncogene Bcl-2,c-myc expression.Results:YWKL in combination with chemotherapy could obviously promoted the expression of GM-CSF gene and inhibited the expression of Bcl-2 and c-myc oncogenes of FC 615 mice.Conclusion:The molecular mechanisms of anticancer and reducing chemotherapy side-effect of YWKL in combination with chemotherapy are to promote the expression of GM-CSF gene and inhibit the expression of Bcl-2 and c-myc oncogenes.

TSP的一个多项式近似算法

给出了TSP的一个多项式近似算法,其运算量为O(n3).

Double Covalency Factors and DoubleξModel in Study on Optical and Magnetic Properties of Diluted Magnetic Semiconductors ZnX∶Co~ 2+

The optical absorption spectra of the covalent crystals ZnX(X=S,Se) doped with Co 2+ are studied using the double covalency factors,which considers the anisotropic distortion of e g and t 2g orbits for d electron.When the paramagnetic g factor is calculated,the contributions of the spin orbit coupling from the ligand ions are taken into account besides that from the central ion,which is the double ξ model.The calculated results indicate that the theoretical values coincide with the experimental values very well.This suggests that the method presented in this paper could be more valid to some strongly covalent crystals.

亏秩最小二乘问题的最优AOR方法(英文)

主要研究了求解亏秩线性最小二乘问题的AOR方法的最优参数、渐近半收敛因子及其明晰的表达形式.并给出了两个数值例子阐明结论.

Effects of rheoforming on microstructures and mechanical properties of 7075 wrought aluminum alloy

It is economically advantageous to cast wrought aluminum alloys directly into near-net-shape components.The objective of the present work is to take advantage of the rheoforming with 7075 alloy to improve the competitiveness of this emerging technology in the manufacture of wrought aluminum alloy.High quality semi-solid slurry was produced,in which primary α(Al) presents in diameter of 62 μm and shape factor of 0.78 and features no eutectics entrapped.Higher forming pressure results in small grain size,improved shape factor and higher density.Especially,rheoforming can effectively reduce the occurrence of hot tearing.The average yield strength and elongation of the rheoformed samples in the T6 condition are 483 MPa and 8%,respectively.

Transport Properties of Si and Ge Liquid Semiconductor Metals

In the present article, we study the electrical resistivity ρ, the thermoelectric power （TEP） α, thermal conductivity σ, Knight-Shifts and temperature coefficient of the Knight-Shifts of the liquid Si and Ge using the well known model potential for the first time. The structure factor used in the present work is derived from the Percus-Yevick （PY） theory. Various local field correction functions are used to study the screening influence. The present results of resistivity are found in qualitative agreement with available experimental and theoretical whenever exists.

Transcriptional regulation of artemisinin biosynthesis in Artemisia annua L.

Artemisinin, also known as qinghaosu, a sesquiterpene endoperoxide lactone isolated from the Chinese medicinal plant Artemisia annua L., is the most effective antimalarial drug which has saved millions of lives.Due to its great antimalarial activity and low content in wild A. annua plants, researches focused on enhancing the artemisin yield in plants became a hotspot. Several families of transcription factors have been reported to participate in regulating the biosynthesis and accumulation of artemisinin.In this review, we summarize recent investigations in these fields, with emphasis on newly identified transcription factors and their functions in artemisinin biosynthesis regulation, and provide new insight for further research.