The nuclear localization signal is required for the function of squamosa promoter binding protein-like gene 9 to promote vegetative phase change in Arabidopsis

Plant Molecular Biology - A mutation in the nuclear localization signal of squamosa promoter binding like-protein 9 (SPL9) delays vegetative phase change by disrupting its nuclear localization. The...     

唐古特白刺果粉的抗氧化作用研究

通过自由基体系和亚硝酸盐体系对白刺果粉体外总抗氧化活性进行了评价,为进一步开发利用白刺资源提供理论依据和试验资料。结果表明,白刺果粉具有良好的抗氧化活性,能有效清除DPPH.、.OH、O2-.、亚硝酸盐,其清除效果与果粉浓度成正相关,最高清除率分别达到65.7%、71.5%、83.8%和71%。     

岳西县来榜镇桑园土壤动物群落及其多样性研究

生物多样性保护是当今世界关注的热点 ,土壤是重要的地下生物宝库 ,土壤生物多样性的保护应予以足够重视。对土壤动物群落的研究 ,目前已有不少报道[3 ] ,但对桑园土壤动物群落及其多样性研究仍属空白。本项工作是在 1999年 1～ 9月对皖西大别山腹地岳西县来榜镇桑园土壤动物调查的基础上 ,探讨桑园这种特殊农业生态类型土壤动物群落多样性特征 ,为进一步提高桑园生产力提供科学依据 ,也为土壤生物多样性保护提供基础资料。1　研究地与方法1 1　研究地自然概况岳西县深处皖西大别山腹地 ,Ｅ115°5 5′～ 116°33′ ,Ｎ31°11′～ 30°39′ ,…     

青海沙棘果粉抗氧化活性的研究

为了深入了解青海沙棘果粉的品质,助其实现规模化生产,从1,1-二苯基苦基苯肼自由基(DPPH·)体系、羟基自由基(·OH)体系、超氧阴离子自由基(O-2·)体系和亚硝酸盐(NO-2)的清除效果方面着手,研究了其体外清除自由基活性。结果表明,青海沙棘果粉对DPPH·、·OH、O-2·和NO-2均有清除作用,且对DPPH·、·OH的清除能力优于O-2·和NO-2。     

Theoretical studies on the interaction of biphenyl inhibitors with Mycobacterium tuberculosis protein tyrosine phosphatase MptpB

MptpB is an essential secreted virulence factor for M. tuberculosis. Inhibition of MptpB impairs mycobacterial survival in host macrophages and thus helps reduce tuberculosis infections. However, the binding mode of the biphenyl inhibitors, which are known as some of the most potent MptpB inhibitors, remains unclear. In this study, to understand the interactions between biphenyl inhibitors and MptpB, docking and molecular dynamics simulations were carried out using AutoDock and GROMACS softwares. Calculation results show that all the biphenyl inhibitors can be docked to the binding site of MptpB, with the acid warheads forming a hydrogen bond network at the active site. But the binding modes of other terminals of these inhibitors are different. The cyclohexyl and trifluoromethyl substituents at R1 and R2 sites are necessary for the inhibitors to adopt their double-site binding mechanism. The estimated binding affinities are basically consistent with the experimental results. MD simulations show that these binding complexes display different stability.     

Progressive Regulation of Electrical and Thermal Transport Properties to High‐Performance CuInTe2 Thermoelectric Materials

p‐type CuInTe₂ thermoelectric (TE) materials are of great interest for applications in the middle temperature range because of their environmentally benign chemical component and stable phase under operating temperatures. In order to enhance their TE performance to compete with the Pb based TE materials, a progressive regulation of electrical and thermal transport properties has been employed in this work. Anion P and Sb substitution is used to tune the electrical transport properties of CuInTe₂ for the first time, leading to a sharp enhancement in power factor due to the reduction of electrical resistivity by acceptor doping and the increase of the Seebeck coefficient resulted from the improvement of density of states. Concurrently, In₂O₃ nanoinclusions are introduced through an in situ oxidation between CuInTe₂ and ZnO additives, rendering a great reduction in the thermal conductivity of CuInTe₂ by the extra phonon scattering. Then, by integrating the anion substitution and nanoinclusions, a high power factor of 1445 μW m^?1 K^?2 and enhanced ZT of 1.61 at 823 K are achieved in the CuInTe₂ based TE material. This implies that the synergistic regulation of electrical and thermal transport properties by anion substitution and in situ nanostructure is a very effective approach to improve the TE performance of CuInTe₂ compounds.     

分光光度法测定血和小肠组织二胺氧化酶活性

本研究应用分光光度法,测定了健康人血,大鼠小肠组织和血二胺氧化酶（ＤＡＯ）活世。本法简便、经济、速度快、重复性好,测定ＤＡＯ活性,能反应小肠结构和功能情况,对实验和临床均有实用价值。