与Chevalley群F4(2)有关的几乎单群的OD-刻画

利用有限群的群阶和度数型,对与Chevalley群F4(2)有关的几乎单群进行了刻画.得到了:Aut(F4(2))为OD-刻画;2.F4(2)为2-重OD-刻画.     

有限单群L_6（5）的OD-刻画

用一个新的引理来处理素图连通的有限群,并由此证明了射影特殊线性群L6(5)是可OD-刻画的.     

完全正则半群上的3个偏序关系

通过一些偏序关系刻画了左密码群并半群、局部正则密码群并半群、局部左正则密码群并半群.证明了完全正则半群S是左密码群并半群当且仅当M=≤;S是局部正则密码群并半群当且仅当B=≤;S是局部左正则密码群并半群当且仅当P=≤.     

对称群S_5的特征标表构造

利用有限群论特征标理论中关于特征标的正交性构造了对称群S5的特征标表。     

关于完全正则半群同余对的一个公开问题

称S是(K)-酉的,如果S的每个正规子集是酉的.对关于同余对的公开问题"刻画关于任意K∈(K)(S),τ∈(JN)(S),(K,τ)∈(TP)(S)的完全正则半群"进行了探讨.得出:关于任意K∈(K)(S),τ∈(JN)(S),(K,τ)∈(TP)(S)当且仅当S是(K)-酉的密码群并半群.     

用不可补子群个数刻画单群A5

设G是有限群,H≤G.如果G中存在子群K≤G,满足G=KH,且H∩K=1,那么称H在G中可补.研究子群的可补性对有限群结构和性质的影响是群论研究中十分重要的课题.给出了5次交错群A_5的一个新刻画,即60阶群G≌A_5的充分必要条件是G中只有46个不可补子群.     

关于n×n矩阵分解为对称矩阵的乘积问题

设F为一域,Mn(F)是F上所有n×n矩阵的集合,Gn(F)是Mn(F)中非奇异矩阵所成的乘法群。设S∈Mn(F) ,ST 表示S的转置矩阵,如果S=ST,则称S为对称矩阵。引理1　　A∈Mn(F) ,P∈Gn(F) ,若A可分解为两个对称矩阵的乘积,则P- 1 AP也可分解为两个对称矩阵的乘积。证:设A有对称矩阵分解式:A =B1 B2 ,则P- 1 AP =P- 1 B1 B2 P =P- 1 B1 (P- 1 ) TPTB2 P令S1 =P- 1 B1 (P- 1 ) T,S2 =PTB2 P ,显然S1 、S2 为对称矩阵,且有P- 1 AP =S1 S2定义1　设A =(aij)∈Mn(F) ,若有aij =an-j+1 ,n -i+ 1 ,　　( 1 )则A是关于次对角线对称…     

鲤45S rDNA的染色体荧光原位杂交定位

应用荧光原位杂交技术,通过设计位于5.8S rDNA、18S rDNA和非转录IGS区域的3条探针CAAG1191、CAAG1845和CAAG3602,分别对散鳞镜鲤Cyprinus carpio var.scattered mirror和松浦鲤Cyprinus carpio Songpu的45S核糖体DNA(ribosomal DNA,rDNA)进行染色体定位及共定位.结果表明:45S rDNA均位于两品种鲤一对近端着丝粒染色体的短臂末端,具有染色体特异性,表明45S rDNA序列的探针能够在鲤细胞遗传学研究中用于标识其所在染色体,并与鲤遗传连锁图谱中长度为227 cM的1号连锁群相对应;两品种鲤的染色体数目均为2n=100,45S rDNA在鲤基因组内仅定位于一对同源染色体,不存在复制位点,证实了鲤基因组在全基因组复制事件之后又经历了重新二倍化过程.     

单群PSL2(7)的特征性质及其初等证明

群的阶、谱及素图是有限群研究的基本工具.利用有限群的数量性质(如群的阶,元素的阶,素图等)来研究群的结构和性质是有限群研究的热点问题.施武杰教授率先提出用纯数量来刻画有限单群,即利用"两阶"来刻画有限单群,并提出了著名的施武杰猜想.目前,该猜想已经完全被解决.然而,回顾以往的工作,作者大多运用了单群的分类定理.尝试不用单群分类定理,仅利用谱来刻画有限单群PSL_2(7),用初等方法证明了G≌PSL_2(7)当且仅当π_e(G)={1,2,3,4,7}.     

基于置换群的可逆逻辑门网络级联

n输入n输出可逆逻辑门的级联构成一个群，它与对称群Sτ同构。本文研究了生成Toffoli门集合的可逆逻辑门数的特点，证明了任意置换Sn可以由n-轮换δ和一个置换τ=（ij，ik）生成，同时证明了相邻2一轮换可由至多两个NOT门在不增加额外信息位的情况下生成。最后提出了一个基于上述理论的可逆逻辑门网络级联算法，并通过实例验证了该算法的正确性。     

A Classification of 45 Maize Inbred Lines Used in China with RFLP Markers

The classification of heterotic groups is essential to maize breeding because knowledge of heterotic groups could be interest to both the combination of outstanding hybrids and the improvement of elite inbred lines. RFLP has provided a powerful tool to assign maize inbred lines into heterotic groups. In this investigation, 45 inbred lines, used widely in south and southwest China, were chosen for RFLP analysis,among which 4 lines came from American, representing different heterotic groups in U.S. corn belt. 54 RFLP core markers covering 10 chromosomes of maize were used. A total DNA of each sample was digested with EcoR I, BamH Ⅰ and Hind Ⅲ . The procedure of RFLP was employed as described by a manual from maize RFLP lab at University of Missouri, Columbia. A total of 860 bands were detected among 45 inbred lines based on RFLP analysis, which were involved in 212 loci. Alleles at each locus ranged from 2 to 9 with an average of 4.06. In total, The 45 inbred lines were classified into 6 heterotic groups according to RFLP data with Ward‘s method. 3 heterotic groups, including Mo17, B73 and Oh43 respectively, seemed to be the same to U. S. heterotic groups. 21 inbred lines, most of which derived from Chinese local germplasm, were classified together into two heterotic groups, indicating domistic germplasm was different from U. S.germplasm at the molecular level and played an important role in maize hybrid production in China. Two inbred lines from tropic germplasm were assigned in the same group. These results provided useful information for our understanding maize heterotic groups and heterotic patterns in China.     

Increasing the potency and breadth of an HIV antibody by using structure-based rational design

Antibodies against the CD4 binding site (CD4bs) on the HIV-1 spike protein gp120 can show exceptional potency and breadth. We determined structures of NIH45-46, a more potent clonal variant of VRC01, alone and bound to gp120. Comparisons with VRC01-gp120 revealed that a four-residue insertion in heavy chain complementarity-determining region 3 (CDRH3) contributed to increased interaction between NIH45-46 and the gp120 inner domain, which correlated with enhanced neutralization. We used structure-based design to create NIH45-46(G54W), a single substitution in CDRH2 that increases contact with the gp120 bridging sheet and improves breadth and potency, critical properties for potential clinical use, by an order of magnitude. Together with the NIH45-46-gp120 structure, these results indicate that gp120 inner domain and bridging sheet residues should be included in immunogens to elicit CD4bs antibodies.     

Genetically determined sex-reversal in 46,XY humans

Evidence is presented for the existence of a gene, probably on the X chromosome, which prevents testis differentiation when present in 46,XY human embryos. Affected 46,XY women are not completely normal because of premature ovarian involution, as a result of which they have "streak gonads" similiar to those of 45,X women.     

硫肥对大豆蛋白亚基含量的影响

试验利用SDS-PAGE方法分析了硫肥水平对3个大豆品种东农46、黑农35和北9395的7S和11S球蛋白亚基含量的影响。小区试验结果表明,施硫增加北9395 7S和11S球蛋白亚基含量,11S/7S降低。东农467S球蛋白亚基含量增加,11S球蛋白亚基含量降低,11S/7S降低。黑农35 7S和11S球蛋白亚基含量降低,11S/7S增加。盆栽试验结果表明,施硫增加北9395 7S球蛋白亚基含量,11S球蛋白亚基含量降低,11S/7S降低。东农46 7S和11S球蛋白亚基含量降低,11S/7S增加。黑农35 7S和11S亚基含量降低,11S/7S增加。     

木质纤维生物量一步法(SSF)转化成乙醇的研究(Ⅱ)——纤维素酶解条件的研究

该研究以汽爆毛白杨木粉作为底物 ,研究了反应温度、作用 pH值、酶的用量和作用时间对纤维素酶解的影响 .研究结果表明 :反应温度、作用 pH值、酶的用量和作用时间对纤维素酶解爆破后的毛白杨木粉都有很大的影响 .酶解最佳条件 :温度 45℃、pH 5 .0、时间 80h ,酶的用量 2 5U/g .     

甘蓝抗枯萎病SCAR标记的开发

 【目的】开发与甘蓝枯萎病抗性基因紧密连锁的SCAR标记,利用该标记对甘蓝抗枯萎病基因跟踪、鉴定,为甘蓝抗枯萎病分子标记辅助选择奠定基础。【方法】以高抗枯萎病的甘蓝自交系8024与感病自交系6A为亲本构建F2代分离群体和相应F3代家系,通过F3代家系抗病性分离表现确认F2代单株的基因型,选择10株纯合基因型显性抗病单株和10株纯合基因型隐性感病单株,利用BSA法构建甘蓝抗感基因池,筛选出与甘蓝枯萎病抗性基因紧密连锁的AFLP标记,克隆测序后根据序列差异将其转化为SCAR标记,通过142株F2代分离群体连锁验证该标记与甘蓝枯萎病抗性基因的连锁关系,并利用两个不同的抗感分离F2群体共100株对SCAR标记的通用性进行验证。【结果】获得了1个以相斥相连锁的SCAR标记S46M48199,该标记在感病亲本中扩增出199 bp的单一条带,而在抗病亲本中无扩增条带,142株F2代分离群体连锁分析表明,其遗传距离为2.78 cM,在F66和C1两个F2群体中的通用性验证结果,与抗性鉴定结果的吻合率分别为81%和83%。【结论】开发的SCAR标记可用于甘蓝抗枯萎病的分子标记辅助育种。     

高温对亚洲柑橘木虱死亡率和活动行为的影响

[目的]研究高温对亚洲柑橘木虱死亡率和活动行为的影响,为亚洲柑橘木虱的防治提供理论依据.[方法]在光照培养箱中模拟高温环境,研究40、42、44、45和46℃高温条件下亚洲柑橘木虱的死亡率;研究36~46℃逐渐升温对亚洲柑橘木虱活动行为的影响;在45℃下,研究不同光照对亚洲柑橘木虱死亡率的影响,以及36与45℃循环变温对亚洲柑橘木虱死亡率的影响.[结果]在40、42、44、45和46℃高温条件下50%亚洲柑橘木虱死亡时间(LT50)分别为138.038、17.140.、11.695、10.593和0.337 h;95%亚洲柑橘木虱死亡时间(LT9s)分别为181.970、26.978、18.843、14.718和0.500 h:在36~46℃逐渐升温过程中,亚洲柑橘木虱的活动逐渐增强;高温(45℃)条件下暗处理的LT50和LT9s分别为6.353和8.913 h,均小于正常光照处理的10.593和14.718 h,而36与45℃循环变温的LT50和LT95分别为13.740和18.967 h,均大于恒温处理的10.593和14.718 h.[结论]高温导致木虱种群生存时间缩减是亚洲柑橘木虱在高温季节出现种群消退现象的主要原因.     

遮阴对凤仙花生长和开花的影响1）

以凤仙花为试验材料,研究了一层遮阴（遮光度为45％,简称S45）、二层遮阴（遮光度为70％,简称S70）、CK（全光照）对凤仙花生长和开花的影响。结果表明：与CK相比,S45和S70的凤仙花株高分别增加了48．02％、34．16％,叶片数分别减少了8．28％、68．98％;两个遮阴处理组叶片叶绿素总质量分数分别比CK增加了1．31、1．39 mg· g－1,均达到极显著水平（ p＜0．01）,净光合速率分别减少了0．93、4．52μmol· m－2· s－1,也达到了极显著水平（ p＜0．01）;S45和S70的开花持续时间分别比CK减少了18、19 d,植株成活率分别降低了17．63％、33．75％,同时,CK、S45和S70在盛花期当日的平均开花量分别为2．78、4．20、3．50朵·株－1,至观测结束,CK、S45和S70的平均结实量分别为89．13、112．29、54．00个。因此,适度的遮阴有利于增加凤仙花植株的单株开花量,提高凤仙花的观赏价值,而过度的遮阴则会对凤仙花的生长甚至繁育产生不良影响。     

Ribosomal RNA synthesis and processing in a particulate site in the HeLa cell nucleus

A particulate fraction has been isolated from detergent-prepared HeLa cell nuclei. The fraction consists largely of organelles that resemble the nucleoli of intact cells. The 45S RNA that is precursor to 28S and 18S ribosomal RNA is associated with the fraction. The 32S RNA that is labeled after the 45S RNA and is the apparent precursor to 28S RNA is also associated with the fraction. The nucleoplasm contains 28S RNA that behaves as an intermediate between the 32S nucleolar RNA and the 28S cytoplasmic RNA.