Novel reference gene, High-mobility-group protein I/Y, used in qualitative and real-time quantitative polymerase chain reaction detection of transgenic rapeseed cultivars

With the development of transgenic crops, regulations to label the genetically modified organisms (GMOs) and their derived products have been issued in many countries. Polymerase chain reaction (PCR) methods are thought to be reliable and useful techniques for qualitative and quantitative detection of GMOs. These methods are generally needed to amplify the transgene and compare the amplified results with that of a corresponding reference gene to get the reliable results. Specific primers were developed for the rapeseed (Brassica napus), high-mobility-group protein I/Y(HMG-I/Y) single-copy gene and PCR cycling conditions suitable for the use of this sequence as an endogenous reference gene in both qualitative and quantitative PCR assays. Both methods were assayed with 15 different rapeseed varieties, and identical amplified products were obtained with all of them. No amplification was observed when templates were the DNA samples from the other species of Brassica genus or other species, such as broccoli, stem mustard, cauliflower, Chinese cabbage, cabbage, sprouts, Arabidopsis thaliana, carrot, tobacco, soybean, mung bean, tomato, pepper, eggplant, plum, wheat, maize, barley, rice, lupine, and sunflower. This system was specific for rapeseed. Limits of detection and quantitation in qualitative and quantitative PCR systems were about 13 pg DNA (about 10 haploid genomes) and about 1.3 pg DNA (about 1 haploid genome), respectively. To further test the feasibility of this HMG-I/Y gene as an endogenous reference gene, samples containing transgenic rapeseed GT73 with the inserted glyphosate oxidoreductase (GOX) gene were quantitated. These demonstrated that the endogenous PCR detection systems were applicable to the qualitative and quantitative detection of transgenic rapeseed.     

Relationship between the molybdenum phases and the conversion of n-butane over Mo/HZSM-5

The conversion of n-C₄H₁₀ was undertaken on MoO₃/HZSM-5 catalyst at 773–973 K and the phases of molybdenum species were detected by XRD. The XRD results show that bulk MoO₃ on HZSM-5 can be readily reduced by n-C₄H₁₀ to MoO₂ at 773 K and MoO₂ can be gradually carburized to molybdenum carbide above 813 K. The molybdenum carbide formed from the carburization of MoO₂ with n-C₄H₁₀ below 893 K is -MoC_1−x with fcc-structure, while hcp-molybdenum carbide formed above 933 K. During the evolution of MoO₃ to MoO₂ (>773 K) or the carburization of MoO₂ to molybdenum carbide (>813 K), deep oxidation, cracking and coke deposition are serious, in particular at higher reaction temperatures, these lead to the poor selectivity to aromatics. Aromatization of n-C₄H₁₀ can proceed catalytically on both Mo₂C/HZSM-5 and MoO₂/HZSM-5, the distribution of the products for the two catalysts is similar below 813 K, but the activity for Mo₂C/HZSM-5 is much higher than that for MoO₂/HZSM-5.     

The drawing behavior of Y-Ba-Cu-O sol from non-aqueous solution by a complexing process

A complexing process is developed to prepare Y-Ba-Cu-O superconducting fibers. The process is not identical to typical sol-gel processes; here the resulting gel network is built up by hydrogen bonding linkage among complexing species in non-aqueous solution. Cu acetate, [Cu(OAC)₂], Ba methoxyethoxide [Ba(ORE)₂] and Y acetate [Y(OAC)₃] are used as precursors for preparing homogeneous gels while -methacrylic acid (HOAA) and diethylenetriamine (DETA) as complexing agents, and methoxyethanol (REOH) as solvent. Fibers drawn from a sol obtained through reduced pressure present no or little deformation at 80°MoC via adjusting the amount of DETA and HOAA. Cu(OAC)₂, Ba(ORE)₂ and Y(OAC)₃ in the complexing process have been demonstrated to form gels without hydrolysis and condensation at ambient atmosphere. The relationships between the drawing behavior of sols and gel structure with different amounts of DETA and HOAA are suggested. The concentration region of drawing the gel fibers with no or little deformation heated at 80°MoC is also found.     

Effect of Pluronic F127 on the pore structure of macrocellular biodegradable polylactide foams

Thermally induced phase separation technique was utilized to fabricate biodegradable poly(l ‐lactic acid) (PLLA) macrocellular foams which were capable of being applied in tissue engineering. The block copolymer Pluronic F127 composed of (polyethyleneoxide)‐(polypropyleneoxide)‐(polyethyleneoxide) [(PEO)‐(PPO)‐(PEO)] was used as a porogen. Water/dioxane mixtures with different volume ratios were used as solvents. The addition of Pluronic F127 could induce an appearance of large pores (50–200 μm) besides small pores (10–20 μm) or a change from a solid–liquid phase separation to a liquid–liquid phase separation. The role of Pluronic F127 depends on the water/dioxane ratios in the PLLA/dioxane/water system. The X‐ray diffraction patterns and porosity measurement results showed that Pluronic F127 was crystallized and existed on the pore wall. The effect of Pluronic F127 on changing pore structure is attributed to the occurrence of the interaction of the lipophilic PPO blocks in Pluronic F127 with PLLA clews, consequently, this results in PLLA aggregation and early phase separation on cooling. Copyright © 2004 John Wiley & Sons, Ltd.     

微波辐照增强原煤磁分离脱硫机理探讨

采用~(57)Fe穆斯堡尔谱学方法,研究微波-磁分离法脱硫机理及微波辐照深度对脱硫率的影响。结果表明,微波选择性介质加热,可以激励煤中顺磁性黄铁矿FeS_2热解,使其转化为非化学计量的磁黄铁矿Fe_(1-x)S(0相似文献   

Synthesis and characterization of poly(amide sulfonamide)s (PASAs)

New diamino monomers IIa – IIg were synthesized in a two-step reaction sequence starting from p-acetamidobenzenesulfonyl chloride. Solution polymerization of these monomers in DMAC with terephthaloyl or isophthaloyl chloride resulted in the formation of a series of 14 poly(amide sulfonamide)s (PASAs) in excellent yield (> 95%). The polymers have in-trinsic viscosities of 0.32–1.11 dL g^?1. Except for polymers IIIa ? p and IIId - p , all other PASAs were readily soluble in aprotic polar solvents including DMAC, DMF, and DMSO. Thermogravimetric analyses of the polymers showed moderate thermal stability with 10% weight loss being recorded in the range of 325–408°C. In addition, these polymers exhibit moderate chemical stabilities toward alkali, acidic, and chromic acid solution. © 1995 John Wiley & Sons, Inc.     

超氧自由基O2-与人的血癌和心肌炎

本报告系采用间接法——分光光度法测定成人、小儿血癌患者及心肌炎小儿血中红细胞的超氧化物歧化酶(简称SOD)活性,以观察O_2~-水平。和正常人的相比 ,患参与之有非常显著(或显著)差异。心肌炎患者滴注大剂量维生素丙,(简称Vc)后,则SOD活性上升至正常水平。它初步提示:间接法适用于人体O_2~-的观察;血癌和心肌炎的发生确与SOD活性或O_2~-水平有关;在剂量Vc对心肌炎的治疗作用也和SOD活性或O_2~-水平的变化有关。     

An investigation of the aggregation and water-air interfacial behaviour of a cationic tentacle molecule

The aggregation and air-water interface properties of a three-legged tentacle molecule tris (11-pyridinium undec-1-yl)benzene-1, 3, 5-tricarboxylate tribromide have been investigated by measurement of the molar conductance, , and equilibrium surface tensin,, over a wide range of bulk concentration (8×10^–6 – 0.3 M). In contrast to the single chain analogue, dodecyl pyridinium bromide, DDPB, the tentacle species shows no evidence for a conventional micellar transition in solutions up to 100 fold more concentrated than the critical micelle concentration of DDPB, though aggregation of small numbers of molecules cannot be excluded. The conductance behaviour suggests the occurrence of ion-pair (or higher) equilibria, which are likely to complicate the interpretation of the data. Also, in contrast to a previous tentacle molecule described in the literature, the present species is significantly surface active, and in the high concentration limit reduces to <30 mNm^–1, significantly lower than the values obtained for simple ionic amphiphiles. In this region the tentacle species seems to stand like a tripod at the water-air interface with both its hydrocarbon legs and its aromatic body lifted clear of the water surface. At much lower concentrations two small plateau regions in are apparent ( 60 and 52 mNm^–1). Here, the tentacle molecule occupies a much larger surface area, and seems to adopt a crab-like crouch with its aromatic body and polar ester substituents lowered into the water surface.     

Activation analysis of mercury in urine samples of electrolysis cell workers

The activation method of determination of trace amounts of Hg in human urine has been studied by introducing a simple amalgam deposition method. Human urine samples were obtained from the alkali chloride, electrolysis plant equipped with Hg cells. The capacity of Cu powder for Hg quantity, the pH conditions, and the shaking time were described. The results showed that the Hg contents in workers' urine samples varied from 33 ppb to 60 ppb depending on working conditions.