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Split Ratio (split + ratio)
Selected Abstracts13C-Labeled metabolic flux analysis of a fed-batch culture of elutriated Saccharomyces cerevisiaeFEMS YEAST RESEARCH, Issue 4 2007Roeland Costenoble Abstract This study addresses the question of whether observable changes in fluxes in the primary carbon metabolism of Saccharomyces cerevisiae occur between the different phases of the cell division cycle. To detect such changes by metabolic flux analysis, a 13C-labeling experiment was performed with a fed-batch culture inoculated with a partially synchronized cell population obtained through centrifugal elutriation. Such a culture exhibits dynamic changes in the fractions of cells in different cell cycle phases over time. The mass isotopomer distributions of free intracellular metabolites in central carbon metabolism were measured by liquid chromatography,mass spectrometry. For four time points during the culture, these distributions were used to obtain the best estimates for the metabolic fluxes. The obtained flux fits suggested that the optimally fitted split ratio for the pentose phosphate pathway changed by almost a factor of 2 up and down around a value of 0.27 during the experiment. Statistical analysis revealed that some of the fitted flux distributions for different time points were significantly different from each other, indicating that cell cycle-dependent variations in cytosolic metabolic fluxes indeed occurred. [source] The Information Content of Multiple Stock SplitsFINANCIAL REVIEW, Issue 4 2008Gow-Cheng Huang G14 Abstract We examine the relationship between the frequency of stock splits and firms' motives for splitting their stock. Compared to their peers, infrequent splitters show higher post-split operating performance, but not so for frequent splitters. We find that split ratio and liquidity change explain the stock split announcement effect for the frequent splitters. In contrast, the change in operating performance in the split year explains the announcement effect for the infrequent splitters. Our results suggest that frequent splits are more consistent with the trading range-improved/liquidity hypothesis and infrequent splits are more consistent with the signaling hypothesis. [source] Effect of Dispersion on Particle Segregation Due to Sparged Air in a HydrocycloneTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3-4 2003Shijie Liu Abstract Fractionation of kraft wood pulp fibres was carried out in a hydrocyclone. Long fibres tend to migrate to the low shear region and report to the overflow stream. Excellent fractionation was found at high pulp slurry feed rates with a split ratio between 0.07 and 0.3. However, when air bubbles are sparged, all the fibres are more uniformly distributed inside the hydrocyclone. When increasingly more bubbles are present, on the other hand, long fibres drain down slower because of rapidly rising air bubbles. Thus, more long fibres report to the overflow stream at extremely high air injection rates. On a effectué le fractionnement de fibres de pâte de papier kraft dans un hydrocyclone. Les fibres longues tendent à migrer vers la région de cisaillement fauble et à rejoindre le courant de surverse. Un excellent fractionnement a été trouvé à des vitesses d'alimentation des suspensions de pâte élevées avec un taux de division compris entre 0,07 et 0,3. Toutefois, lorsque les bulles d'air sont dispersées, toutes les fibres sont distribuées de manière plus uniforme dans l'hydrocyclone. Par ailleurs, à mesure que le nombre de bulles augmente, les fibres longues descendent plus bas à cause des bulles d'air qui montent rapidement. Ainsi, davantage de fibres longues se retrouvent dans le courant de sousverse à des vitesses d'injection de l'air extrêmement élevées. [source] Development of two cell culture systems from Asian seabass Lates calcarifer (Bloch)AQUACULTURE RESEARCH, Issue 1 2006Wazir S Lakra Abstract Two new cell culture systems namely epitheloid cells of Lates (LCE) and fibroblastic cells of Lates (LCF) have been developed from fry and fingerling of the economically important brackishwater fish Lates calcarifer. Primary cultures were initiated by explant technique using caudal fin of fingerling and whole body tissue of the fry. The nutritional requirements and the growth pattern in response to different culture environment were similar for the two cell cultures. The culture medium used was Leibovitz-15 supplemented with 20% fetal bovine serum (FBS) and 1% fish serum. The LCE comprised of epithelioid cells and LCF cells were fibroblastic. With a split ratio of 1:2, the confluency of cells was attained in 8,10 days at an incubation temperature of 28°C. The cells were found to grow well in a wide range of temperature (24,32°C) and stable at 20 and 36°C. The growth rate of LCF and LCE cells increased proportionately with the concentration of FBS from 5% to 20%. A decrease of serum level to 10% after eight subcultures produced no apparent change in cell morphology and growth rate. The viability of cells was found to be 70% when revived after a month of storage in liquid nitrogen (,196°C). [source] Determination of curcumol in rat plasma by capillary gas chromatography with a hydrogen flame ionization detectorBIOMEDICAL CHROMATOGRAPHY, Issue 4 2010Xiao Zhao Abstract A simple and sensitive capillary gas chromatography with a hydrogen flame ionization detector (GC-FID) method was developed for the determination of curcumol in rat plasma. From a variety of compounds and solvents tested, buagafuran was selected as the internal standard (IS) and acetonitrile was found to be the best protein precipitation agent and solvent for extracting curcumol from plasma and tissues samples. (Buagafuran was used as an internal standard. Curcumol was extracted by a protein precipitation with acetonitrile.) The samples were determined by GC on an HP-5 column (30.0 m × 0.32 mm, 0.25 ,m); inlet volume 2 ,L; split ratio 10 : 1; inlet temperature 250°C; oven temperature 180°C; flow 1.0 mL/·min; FID 250°C; carrier gas N2. The resulting retention times of curcumol and IS were 6.0 and 9.5 min. There was good linearity over the range 0.133,133.3 ,g/mL (r = 0.9999) in plasma samples. The method recoveries were 97.7,102.0% in plasma, and the intra- and inter-day variances (RSD) were less than 15% in all cases. The GC method was applied to develop a pharmacokinetics study in which experimental rats received a single administration of curcumol by intravenous injection. Copyright © 2009 John Wiley & Sons, Ltd. [source] A Method for the Design of Divided Wall ColumnsCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 9 2007N. Sotudeh Abstract A divided wall column has been modeled as a Petlyuk column with no heat transfer across the column wall. The feed to the column has been generalized as a mixture of saturated liquid and vapor (0 split ratio is suggested. This is a novel approach not attempted before by investigators. [source] | ||||||||||