Research on magnetic metallization of bacterial cells

A multidisciplinary approach to the fabrication of biologically based magnetic monomers for biolimited forming is described.Rod-like Bacilli cereus about 0.5μm in diameter and 3-5μm in length,were used as templates on which the ferromagnetic material was deposited by an electroless deposition method.Different electroless plating solutions were compared in detail and CoNiP solution was selected.During the deposition process,both dispersant and mechanical stirring were used to solve the problem of aggregation of bacterial cells so as to obtain a uniform plating layer.The CoNiP film on Bacilli cereus was a mixture of crystalline and non-crystalline in the phase structure and showed a good magnetism.The magnetic metallized bacterial cells could be manipulated with a magnetic field.Parallel arrays of these micro magnetic particles were achieved and they could rotate along with the magnetic field.     

Syntheses of oxysterol receptors‘(LXRs)ligands

The LXRs‘ and agonist,24S,25-epoxycholesterol 1,was synthesized stereoselectively(100%d.e.)in 56% overall yield from methyl hyodeoxycholanate 4 in 9 steps with des mosterol acetate 11 as the key intermediate and the modified Sharpless asymmetric dihydroxylation as the key step.The LXRα subtype selective agonist 5α,6α,24S,25-diepoxycholesterol 2 and the novel LXRs‘ ligand 5β,6β:24S,25-diepoxycholesterol 3 were also synthesized from 1.     

Therapeutic angiogenesis induced by human hepatocyte growth factor (HGF) gene in rat myocardial ischemia models

Coronary arteriosclerotic cardiopathy is also named myocardial ischemia, which severely threatens humanhealth. Following the economic development and change of life style in China, population blood pressure, weight index and serum cholesterol level all rise. This prophesies incidence rate of coronary arteriosclerotic cardiopathy and stroke will increase year by year. Angioplasty and surgical bypass, the primary interventional therapies for these in-dividuals, are temporally limited by the prob…     

Present status and development on biological nitrogen fixation research in China

This presentation introduces the advances in biological nitrogen fixation research abroad, in particular,describes the great progress and achievements on its research in China as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium in China, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes, identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen,temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is not controlled by flavonoid produced from its host alfalfa; finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulation factor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on the research of gene expression and regulation; chemical simulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of model compounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research in China in future has been put forward, suggesting that the nif gene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbon and nitrogen metabolisms, nitrogen fixation and photosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.     

Involvement of Ca<Superscript>2+</Superscript>/CaM in the signal transduction of acetylcholine regulating stomatal movement

It has been known that the neurotransmitter acetylcholine (ACh) also exists in plants and is able to regulate the movement of stomata.In another aspect,Ca^2 /CaM as the second messengers have a critical role of signal transduction in stomatal guard-cell,Here we showed that Ca^2 /CaM were also involved in the ACh regulated stomatal movement,In the medium containing Ca^2 ,the Ca^2 channel blockers (NIF and Ver)and CaM inhibitors (TFP and W7 ) could neutralize the ACh induced stomatal opening,however,they are ineffective in the medium containing K^ ,Those results indicated that Ca^2 /CaM were involved in the signal transduction pathway of ACh regulating stomatal movement.     

Origin of two differentiation trends in the Emeishan flood basalts

Both the Bowen and Fenner differentiation trends have been recognized in the Emeishan flood basalts.While the Longzhoushan laveas in Panxi paleorift evolved on a trend of silica enrichment (Bowen trend),the lavas from Guizhou evoled along the Fenner trend leading to the magmas with high Fe2O3 (23%) and low SiO2(44%) contents,This provides evidence for the existence of Fe-rich and Si-poor magmas in nature ,Such contrasting differentiation trends,marked by different timing of crystallization of Fe-Ti oxides,are correlated with the extent of crustal contamination of the magmas ,Linited crustal contamination in the Guizhou lavas is coupled with the low oxygen fugacity which delayed the onset of magnetite crystallization .In contrast,significant involvement of crustal components in the Long-Zhoushan lavas increased fo2 which in turn triggered early crystallization of magnetite.The close spatial association between the Longzhoushan lavs and the synchronous V-Fe-Ti deposit-bearing layered intrusions suggests a potential relationship between them.     

Quasi-particle injection into YBa2Cu3O7-δ micro-bridge

The perspectives of fast three-terminal (3T) super- conducting devices with considerable gain have triggered many research activities on suppression of superconductivity; especially on that in high-Tc superconductors[1—3] and many achievements have been obtained. Unfortunately, certain factors such as current superposition and heating are overlooked in some experiments, thus leaving much room for improvement. With YBCO micro-bridges, we have looked at quasiparticle injections in the forms o…     

<Emphasis Type="Italic">ftsZ</Emphasis> gene and plastid division

As the important cellular organelles in plants, plas-tids comprise one of the primary features that distinguish plant cells from those of other eukaryotes. Seen from the origin, plastids derive from endosymbiotic photosynthetic bacteria. Subsequently, plastids have evolved to become essential components for plant cell function. Besides the important role of chloroplasts in photosynthesis, some water-soluble proteins that involved in biosynthesis of starch, fatty acids, amino acids, nucleic aci…     

Effect of solvents on the barrierless reaction in the excited state of cyanine dye

UV－Vis,fluorescence spectroscopy and time resolved spectroscopic technique on picosecond and femto-second scales have been utilized to investigate the effect of steric hindrance and multiple hydroxyl groups of solvents on the barreierless isomerization in excited state of 3,3 ′-di(3-sulfopropyl)thiacyanine triethylamminium salt,The results show that the factors mentioned above may be responsible for a different “short-time behavior “of the bleaching signal on the ground state and nonlinear viscosity dependence of the excited-state lifetime in ispropanol and glycol,These phenomena are distinguished from the situation repored in the long-chained monhydroxyl alcoloh solvents.However,the dye molecule still exhibits the analyzing-wavelength dependence of the observed fluorescence lifetime,that is ,the fluorescence lifetime increases with the increasing of analyzing-wavelength ,The conclusions are in agreement with those drawn from femtosecond upconversion fluorescence experiments and further exemplify the barrierless isomerization model in the excited state.