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Doublesex and mab-3-related transcription factor 1 (Dmrt1) is a Z-linked gene that putatively determines the phenotype of gonads in birds. The sex differential expression of Dmrt1 was examined using wholemount in situ hybridization (WISH) in the urogenital systems during embryogenesis. The results revealed that Dmrt1 showed dimorphic expression in chicken gonads, which increased from day 6.5 to day 10.5. The expression of Dmrt1 in male (ZZ) gonads was not twice as much as in female (ZW) gonads, suggesting the existence of other regulatory mechanisms in addition to Z chromosome dosage effect.

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Abstract  

The dependence upon concentration of sodium chloride of free volume in ovalbumin gels, a main component of an egg white, is studied by the positron annihilation lifetime technique. The average free-volume radius in ovalbumin gels was about 0.27 nm at 298 K, smaller than those of organic polymers such as low-density polyethylene (0.34 nm at 300 K) and polystyrene (0.29 nm at 300 K). These differences suggest that the positronium annihilates in free volumes located close to hydrogen bonds, thus decreasing average free-volume radius. Free-volume content decreased with the increase of NaCl concentration up to 30 mM. At lower concentrations of NaCl, it seems that a correlation exists between microscopic free volume and macroscopic hardness of the ovalbumin.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Y. Wakabayashi, K. Ito, H. Li, Y. Ujihira, H. Hashimoto, H. Matsui, A. Chiba, and Y. Jean

Abstract  

Positron annihilation lifetime measurement was applied to study the sol-gel transition of anionic polysaccharide aqueous solutions in terms of free-volume parameters the size, intensity, and size distribution of free volumes of the gelation of K-formk-carrageenan solutions as a function of temperature. Slight variations of free volume size and intensity against temperature were observed near 295 K. The correlation of free-volume data with other physical properties vibrational spectra (IR and Raman), conductivity, SAXS, elastic measurement, differential scanning calorimetry were investigated to understand the mechanism of sol-gel transition of carrageenan.

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Abstract  

The free-volume, of size ranging from 0.2 to 0.4 nm in radius, in an ethylene-vinyl alcohol copolymer was estimated using positronium lifetime measurement to elucidate the dependence of oxygen permeability on the free-volume size and fraction, on the ethylene content and on the crystallinity. The permeability and the free-volume fraction with varying the ethylene content were well related and the relation was interpreted based on the free-volume theory near below and above the glass transition temperature. On the other hand, the crystallinity significantly influenced the fraction of the amorphous region, where the free-volume hole exists, along with a slight change of the free-volume size. The variation of the permeability with the crystalline degree cannot be explained from the averaged free-volume fraction estimated by the whole volume of the polymer, but the permeability correlated with the free-volume size apparently.

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Abstract  

The size distribution of free-volume (<~0.1 nm3) of ethylene-vinyl alcohol copolymer with various crystalline degrees was estimated by positronium lifetime measurement. With increasing degree of crystallinity, the size distribution significantly narrowed and the intensity of positronium decreased. This indicates that the inhomogeneity reduces with the increase of the degree of crystallinity. It is found that the free-volume fraction estimated is reflected by the fraction of the amorphous region.

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Cereal Research Communications
Authors: X. Zhang, Y. Chen, Y. Wei, W. Lu, H. Liao, Y. Liu, X. Yang, X. Li, L. Yang, L. Li, and R. Li

Partial abortion of gametes possessing S-5 j in S-5 i / S-5 j genotype at locus S-5 is responsible for hybrid sterility between indica and japonica subspecies in rice ( Oryza sativa L.), while a single wide compatibility (WC) allele S-5 n can restore normal hybrid fertility between the two groups. In this study, Pei’ai 64S, one of the most popular WC line widely used for subspecific hybrid rice breeding program in South China was studied for location of its S-5 locus. Twenty SSR (Simple Sequence Repeat) markers derived from Cornell SSR linkage map and 9 developed using sequences from GenBank database were employed to perform bulked segregant analysis of the mapping population derived from a three-way cross (Pei’ai 64S/T8//Akihikari) to tag fine location of the hybrid sterility locus, S-5 . This S-5 locus was mapped on chromosome 6 approximately 0.2 cM from GXR6 and RM276 SSR markers. This tight linkage of the markers and the S-5 locus would be very useful for efficient marker-assisted selection for WC varieties and for map-based cloning of the gene.

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To study the development of starch granules in polyploid wheats, we investigated the expression of starch synthetic genes between the synthetic hexaploid wheat SHW-L1, its parents T. turgidum AS2255 and diploid Ae. tauschii AS60. The synthetic hexaploid wheat SHW-L1 showed significantly higher starch content and grain weight than its parents. Scanning electron microscopy (SEM) showed that SHW-L1 rapidly developed starch granules than AS2255 and AS60. The amount of B-type granule in AS60 was less than that in SHW-L1 and AS2255. RT-qPCR result showed that the starch synthetic genes AGPLSU1, AGPLSU2, AGPSSU1, AGPSSU2, GBSSI, SSIII, PHO1 and PHO2 expressed at earlier stages with larger quantity in SHW-L1 than in its parents during wheat grain development. The expression of the above mentioned genes in AS60 was slower than in SHW-L1 and AS2255. The expression pattern of starch synthase genes was also associated with the grain weight and starch content in all three genotypes. The results suggested that the synthetic hexaploid wheat inherited the pattern of starch granule development and starch synthase gene expression from tetraploid parent. The results suggest that tetraploid wheat could plays more important role for starch quality improvement in hexaploid wheat.

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Abstract  

The characterization of different sized TiO2 (25 nm, 80 nm, and 155 nm) was carried out by transmission electron microscopy (TEM) and the micro-distributions of TiO2 in the olfactory bulb of mice after nasal inhalation were investigated by microbeam SRXRF mapping techniques. The results show that TiO2 particles can be translocated to the olfactory bulb through the olfactory nerve system after inhalation. The distributions of Fe, Cu, and Zn in the olfactory bulb were also studied.

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In this study, the peach kernel proteins were extracted and treated with alkaline proteinase to generate peach kernel protein hydrolysate (PKH), which showed angiotensin converting enzyme (ACE) inhibition activity. The hydrolysate was separated into four fractions and their anti-ACE activities were investigated. Our results showed that all PKHs had anti-ACE activity, and the lowest molecular weight fraction PKH4 had the highest ACE inhibitory activity. Lineweaver–Burk plots illustrated that the inhibition types of PKH3 and PKH4 were non-competitive. The Ki of PKH4 was lower than Ki of PKH3; suggesting PKH4 had high affinity to ACE. Amino acid composition analysis showed that the best anti-ACE peptide PKH4 possessed high levels of hydrophobic amino acids, branched-chain amino acids, and aromatic amino acids. In summary, our findings demonstrated that high anti-ACE activity is negatively related to the size of the PKHs and possibly the composition of amino acids, and the PKH4 was the best ACE inhibitor. Further, peach kernel peptides can be developed as a functional food for patients with hypertension.

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With the continuous expansion of the global dairy trade market, the quality and safety of the Chinese dairy market have a wide and far-reaching impact on the world. Based on the development of the dairy scandal in the past few years in China, this study illustrates the serious damage of melamine on human health and the negative impact on the dairy industry in China.

This study shows that the lack of effective government regulations is a key reason for dairy market failure. Consumers are lacking confidence in the quality of Chinese dairy products and the government's market regulations. The Chinese dairy market will continue to rely on imported dairy products. By analyzing the typical cases of the dairy market in China, this study aims to provide a guide for dairy industries in other countries.

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