BICP0 and its RING finger domain act as ubiquitin E3 ligases <Emphasis Type="Italic">in vitro</Emphasis>

Bovine infected-cell protein 0 (BICP0) encoded by bovine herpes virus 1 (BHV-1) immediate early gene is necessary for efficient productive infection, in a large part,because it activates all 3 classes of BHV-1 genes. It also has the ability to efficiently transactivate promoters that are not derived from BHV-1. To investigate the mechanism by which BICP0 achieves these effects, we expressed and purified BICP0 and its different mutants in E. coil In vitro assays showed that both full-length BICP0 and its isolated RING finger domain induce the accumulation of polyubiquitin chains. Mutations within the RING finger region that abolish the in vitro ubiquitination activity also cause severe reductions in BICP0 activity in other assays. Based on these, we conclude that BICP0 has the potential to act as an E3 ubiquitin ligase during viral infection and its RING finger domain is necessary for this function. These strongly support the hypothesis that BICPO might influence virus infection through its ability to interact with the ubiquitin-proteasome pathway.     

p元m序列的三值互相关分布

设m,k是正整数,e=(m,k)且m/e,k/e均为奇数,p是满足pe≡1(mod 4)的奇素数,d=(pm+1)·(pk+1)/4.确定了指数和∑x∈GF(pm)ζtrm1(αxd+βx)p的值分布,并给出周期为pm-1的p元m序列{st}及其采样序列{sdt}之间的互相关函数的值分布.     

几种羟肟酸捕收剂与白云石作用机理研究

为了更好的揭示羟肟酸类捕收剂与白云石作用机理,利用Materials Studio(MS)软件建立羟肟酸捕收剂在白云石矿物表面的吸附模型,通过分子模拟技术模拟计算了真空环境下药剂分子与白云石矿物的相互作用能。从原子尺度揭示了捕收剂在白云石浮选中的捕收机理,研究表明吸附能的差异是导致捕收剂选择性捕收的根本原因。     

广义彼得森图意大利控制数

图的罗马控制来源于古罗马帝国的军事防御问题.图的意大利控制是一种泛化的罗马控制.确定图的意大利控制数是NP困难的.一般情况下,很难确定某一类图意大利控制数的精确值,只能给出其上界或下界.通过构造可递推的意大利控制函数,得到了广义彼得森图P(n,k)(k≥4)的意大利控制数紧的上界.结合前人给出的意大利控制数的下界,确定了当k≡2,3(mod 5)且n≡0(mod 5)时,P(n,k)(k≥4)意大利控制数的精确值.     

关于局部扭立方体的反馈数

确定一般网络(或图)的最小反馈点集问题属NP难问题.n维局部扭立方体网络Qltn是n维超立方体网络Qn的变形且是一类重要的互连网络拓扑结构,其拥有的某些性质优于Qn.根据Qltn顶点集合中最后一位字节不同的特点,将其顶点集合划分为两个不相交的子集,通过构造极大无圈子图得到反馈数的上界,并证明了对任意正整数n≥2,存在常数c∈(0,1)使得反馈数为f(n)=2n-1(1-c/(n-1)).     

对机器人平面执行机构动力学方程的探讨

文章以开式链平面连杆机构为对象,从新的角度探索分析其动力学方程的建立问题,文中依次对类速度,类角速度,惯性系数,广义力给出新的求解通式,最后用拉格朗日方程建立相应的动力学方程。     

微翅管几何参数对混合工质流动沸腾特性的影响

对非共沸混合工质R32／R134a在水平微翅管内的流动沸腾特性进行了实验研究,获得了微翅管的翅高和翅数对换热性能的影响,并综合比较了3根微翅管的换热性能。同时,将微翅管与光管性能进行了比较。结果表明,在相同工况下,翅高为0．2mm、翅数为60的换热性能最好;微翅管的换热性能明显优于光管。     

A study on the effect of the bacterial inoculant on corn silage quality,digestibility and performance in dairy cattle

Effect of the bacterial inoculant Sil-All (short for ‘ SA‘ ) on corn silage quality, digestibility and performance in dairy cattle was studied. SA treated silage resulted in the higher level of retained protein and slightly higher level of residual sugars in that treatment, the better digestibility of the neutral detergent fibre (NDF) and the acid detergent fibre (ADF), the lower pH and evolution of ammonia compared to the control; The fall in pH was most rapid in the SA treated silage in the first 4 days of ensilage, when it matters most for the conservation of protein, compared with the control silage and this was linked more to both lactic and total acids. Both volatile fatty acid (VFA) and lactate content increased with ensiling time, increase degree reached up near 100%; Lactate content in treatment silage was higher than that in the control, and this difference was all maintained at the level of approximately 7% - 13% almost in all cases, at length, up 16% in the case of day 15; pH value decreased with ensiling time. Moreover, pH value in most of treatment were lower than that in the control ; The digestibility of both dry matter (DM) and crude protein (CP) was appreciably improved by the use of inoculant SA. Also, in relation to reductions, of NDF and ADF were noted. An increase in milk yield of the order of 0.9kg per head per day in favour of SA was observed. Alternatively, with an average daily feed intake of 20kg, this indicates with 1 ton of corn silage milk yield could be increased by 46.5kg.     

Applications and research in frame longeron of hydroforming

The application feasibility of hydroforming in frame longeron large parts is verified for the first time at home. The result of the research on the structure design and process analysis for frame longeron shows that hydroforming can be fully realized.With stiffness is comparison,collision test simulation and cross section force with traditional drawingassembly welding techniques,it has been found that hydroforming combining has multiple advantages such as lightweight, high stiffness,reduction in the number of parts,high precision,hence reduction the associated machining and welding and so on.It is especially suitable for forming various lightweight components used for the chassis parts in automotive.     

路径幂图、Flower Snark图及多锥图独立数

图的独立数是图论中的重要参数,令G=(V(G),E(G))是一个简单有限无向图.如果V(G)的子集S中任意两个顶点均不相邻,则S是图G的一个独立集.顶点独立集大小的最大值,称为图G的独立数,记做α(G).研究了路径幂图、Flower Snark及其相关图、多锥图的独立数问题,首先构造出了它们的独立集,得到其独立数的下界,然后证明了该值也是其独立数的上界,并给出了它们独立数的准确值.