1,288 research outputs found
SOURCES OF AGRICULTURAL GROWTH IN JAPAN, 1880-1965
International Development,
Studies on Sphingolipids, I. Gas-liquid Chromatographic Analyses of Sphingosine Bases.
Three different methods ; permanganate-periodate oxidation, periodate oxidation and trimethylsilylation, for gas-liquid chromatography of sphingosine bases were compared to one another, using authentic dihydrosphingosine as well as bases of cerebroside isolated from pig brain and sphingolipids from yeast powder, with the data on the occurrences of shorter chain homologs of sphingosine bases. The trimethylsilylation method was most suitable for the qualitative determination and identification of individual sphingosine base. This method was also available for the quantitative determination of sphingosine base composition. The periodate method was most suitable for the quantitative determination of sphingosine base composition, except that some uncertainties such as C-15 saturated aldehyde could be derived from either C17-dihydrosphingosine or C18-phytosphingosine, remain to be solved by other methods such as Trimethylsilylation method or thin-layer chromatography etc. The permanganate-periodate method was less suitable for the determination of sphingosine base composition for higher appearance of some oxidation products as well as uncertainties due to same acids could be derived from different parent bases by this method than by periodate method. But it is still useful for the exact determination of the double bond position and helps the identification of the bases with other methods. C16-sphingosine, C16-dihydrosphingosine and probably C17-sphingosine occured at low level in pig brain cerebroside. C18-dihydrosphingosine was predominant base in yeast sphingolipids but the occurrences of C18-phytosphingosine and C20-dihydrosphingosine were also confirmed.departmental bulletin pape
Recommended from our members
Low-Complexity Systolic V-BLAST Architecture
In multiple-input multiple-output systems, an ordered successive interference canceller, termed the vertical Bell laboratories space-time (V-BLAST) algorithm, offers good performance. This letter presents a low-complexity V-BLAST scheme suited for parallel implementation. The proposed scheme, using a greedy ordering, can achieve a performance comparable to that of V-BLAST with optimum ordering, while its computational complexity is lower than a linear detector.Engineering and Applied Science
Recommended from our members
Optimum-Weighted RLS Channel Estimation for Rapid Fading MIMO Channels
This paper investigates on an accurate channel estimation scheme for fast fading channels in multiple-input multiple-output (MIMO) mobile communications. A high-order exponential-weighted recursive least-squares (EW-RLS) method has been known as a good channel estimation scheme in rapid fading. however, there exists a drawback that we need to properly adjust the estimation order according to the channel environment. In this paper, we theoretically derive an optimum-weighted LS (OW-LS) channel estimation based on the statistical knowledge of the spatio-temporal channel correlation. Through the analysis, we reveal that the zero-th order polynomial becomes optimal when the optimum-weighting is employed. Furthermore, we propose an efficient recursive algorithm for channel tracking in oder to reduce the computational complexity. Since the proposed scheme automatically adapts the weighting coefficients to the channel condition, it has a significant advantage in mean-square error (MSE) performance compared to EW-RLS scheme.Engineering and Applied Science
- …