水稻亚种间杂种一化脱粒性的研究

用３２个籼、粳、爪哇型水稻品种配制了－６７个亚种间杂交组合，对这些组合及其亲本所进行的脱粒性研究，结果表明：不同类型的亚种间杂种一代脱粒性没有差异，但同一种类型中不同组合之间的差异却较大；亚种间杂种一代脱粒性的测量值与中亲值呈显著相关，而与亲本没有显著相关；经检验９对亚种间正反交组合的脱粒性其差异没达显著水准。本文还分析了几个常用亲本的脱粒性，并对脱粒性的研究方法进行了讨论。

水稻脱粒性的研究进展及展望

水稻是重要的粮食作物,提高水稻产量是水稻育种的重要目标。在水稻驯化中,许多性状朝着有利于增产的方向发展,尤其是水稻脱粒性的变化。相对于野生稻而言,栽培稻倾向于难脱粒的表型。这有效地保证了水稻谷粒的收获,进而提高了水稻产量。为了更好地理解水稻脱粒性,就水稻脱粒的细胞学基础,基因调控机制,植物激素调节做了相关综述,以期为水稻脱粒性的研究提供有用的信息,并在此基础之上对其做了一些展望。

Performance Characteristics for Nitrogen Removal in SBR by Aerobic Granules

The sequencing batch reactor (SBR) was started up by seeding the anaerobic granular sludge and the aerobic granular sludge was successfully cultivated. The performance characteristic of the aerobic granules for nitrogen removal was investigated in detail. The experimental results demonstrated the relationship between operational parameters [dissolved oxygen (DO) and pH] and variation of chemical oxygen demand (COD), ammonium (NH4+-N)and total nitrogen (TN). In continuous flow pattern, COD was too low in the reactor at the later stage of a cycle,which restrained denitrification and decreased the removal of nitrogen, while in discontinuous flow pattern, the carbon source could be supplemented in time, which improved denitrification and increased the removal of TN from 66% to 81%.

Physical properties and filter cake structure of fine clean coal from flotation

In order to improve the dewatering rate and the effect of fine clean coal(FCC), the advanced method offine coal( 0.5 mm) dewatering and the correlated basic theory were investigated in this study. It was found that the dewatering by sleeve type press filter was an efficient way of FCC dewatering. On the other hand, the results also proved that particle size distribution, volatile matter, ash content, pore size distribution and specific surface area of coal particles of FCC samples, as well as viscosity and density of FCC slurry, were important parameters in determining the process of efficient dewatering. Especially, wet mass to dry mass, specific resistance of average mass, compressibility factor and microstructure of filter cake explained the reasons and mechanisms of fine clean coal efficient dewatering.

Effects of dichloroacetate on the activation of the mitochondrial pathway in C6 cells in vitro

Mitochondria are increasingly recognized as important targets for tumor treatment because of their central roles in apoptotic pathways and cellular metabolism. Dichloroacetate （DCA）, a low molecular weight mitochondria-targeting agent, exhibits potential therapeutic effects for tumors. Based on the effects of DCA on tumor cellular metabolism, we carried out this study to investigate the anti-tumor activity of DCA in C6 glioma cells in vitro. The results showed that DCA was able to increase the activity of pyruvate dehydrogenase （PDH）, induce the production of reactive oxygen species （ROS） and reduce the mitochondrial membrane potential （MMP） in C6 ceils in vitro （P〈0.05 or 0.01）, indicating that the anti-tumor effects of DCA in C6 cells could be through the activation of the mitochondrial pathway. In conclusion, mitochondria could be a viable therapeutic target for the treatment of glioma.

Simultaneous extraction of DNA and RNA from Escherichia coli BL 21 based on silica-coated magnetic nanoparticles

The extraction of nucleic acid is recognized as one of the most essential steps in molecular biology for initiating other downstream applications such as sequencing, amplification, hybridization, and cloning. Many commercial kits and methods are currently available that allow the extraction of only one type of nucleic acids-DNA or RNA. However, in parallel clinical detection of several diseases, a method for simultaneous extraction of both DNA and RNA from the same source is needed in such cases. In this study, a method for simultaneous extraction of DNA and RNA from bacteria based on magnetic nanoparticles(MNPs) was described. Lysis buffers were prepared to help the nucleic acid released and adsorbed to MNPs. Then, two washing buffers were used to remove the contamination of proteins and carbohydrates. The nucleic acids were finally eluted by Deoxyribonuclease(DNase) and Ribonucleases(RNase) free water. Different factors which might affect the purification of the nucleic acid were investigated, and the quantity and quality parameters of the nucleic acid were also recorded. The DNA and RNA extracted from bacteria were then respectively subjected to polymerase chain reaction(PCR) and reverse transcription PCR(RT-PCR) to further confirm its quality. The results indicated that our method can be successfully used to simultaneously extract DNA and RNA from bacteria.

Effects of hydrothermal temperature on formation and decoloration characteristics of anatase TiO_2 nanoparticles

This paper describes the effects of temperature on the complex intermediate processes from the precursor to the fully-crystallized anatase TiO2 nanoparticles in hydrothermal synthesis. The anatase TiO2 nanoparticles were synthesized in a wide temperature range below 230°C. The composition, morphology, and methylene blue (MB) decoloration characteristics of the obtained products were investigated by X-ray diffraction, Fourier transform infrared spectroscope, X-ray photoelectron spectroscope, and scanning and transmission electron microscope. The dehydrating polycondensation of Ti(IV)-hydrates and the decomposition of (NH4)2Ti3O7 intermediates with the temperature increase lead to the direct formation of anatase TiO2 nanoparticles under the hydrothermal environments. The strong MB decoloration of the hydrothermal products obtained at the low (≤130°C) and high (≥180°C) temperatures are attributed to the adsorption of Ti(IV)-hydrates and the photocatalysis of anatase TiO2 nanoparticles, respectively.