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261.
262.
Victor Lilly Martin Birch Bryan Garscadden 《Journal of the science of food and agriculture》1980,31(10):1059-1065
Spent brewers' or distillers' grains are normally disposed of either in the wet form, in which they spoil rapidly, or after drying, which is costly. Alternatively, the storage life of wet grains may be extended by ensiling, which involves on-farm control and equipment. This investigation examines the preservation of spent grains by lowering the water activity of the material using molasses and further stabilising the mixture by incorporating an anti-mycotic agent. Investigations at both laboratory-scale and pilot-scale are reported culminating in the successful stabilisation of the wet grains by the incorporation of 30% of beet molasses and 0.3% of potassium sorbate into the grains after preliminary centrifugation. For effective preservation the stabilised grains should be consolidated in plastic bags followed by closing to leave the minimum possible headspace in the bags. 相似文献
263.
The aroma volatiles, and in particular the glucosinolate products, of seedlings grown from authenticated Lepidium sativum seeds are compared with those from purchased ‘garden cress’. Appreciable differences in the glucosinolate products can be observed showing that retailed ‘garden cress’ contains cruciferous seedlings in addition to, or in place of, L. sativum. Results are compared with a previous analysis of the volatile components of ‘garden cress’. 相似文献
264.
Cristofor I. Simionescu Victor Bulacovschi Doina Macocinschi Gheorghe Stoica Ioan I. Neguiescu 《Polymer Bulletin》1988,19(1):59-63
Summary Suspension type PVC was reacted with sodium phenoxide in presence of different quaternary ammonium halides in THF or THF/water mixtures. The competition elimination vs. substitution of chlorine atoms depends on the homogeneity of the system, i.e. the more homogeneous the reaction mixture the less substituted the polymer.Dedicated to the 60th anniversary of Prof. Otto Vogl 相似文献
265.
The central role of protein kinase C (PK-C) in cellular signal transduction has established it as an important therapeutic target for cancer and other diseases. We have developed a series of 4,4-disubstituted-gamma-butyrolactones, which contain a constrained glycerol backbone (DAG-lactones) and behave as potent and selective activating ligands of PK-C with affinities that approach those of the structurally complex natural product agonists, such as the phorbol esters. This Account traces the design and construction of these molecules. Initially, we examined the consequences of reducing the entropic penalty associated with the transformation of a DAG into a DAG-lactone. Then, using molecular modeling to extend insights arising from the newly solved crystal structure of a C1 domain complexed with phorbol ester, we incorporated amino acid-specific branched hydrophobic chains to provide a new generation of DAG-lactones that have the capacity to bind to PK-C with low nanomolar affinity. Depending on the specific pattern of hydrophobic substitution, some DAG-lactones are able to induce selective translocation of individual PK-C isozymes to different cellular compartments, and since the specific nature of these hydrophobic interactions influences biological outcome, some of these compounds exhibit cell-specific antitumor activity. The ability to direct specific PK-C isozyme translocation with sets of structurally simple, yet highly potent molecules provides a powerful tool for engineering a plethora of molecules with novel biological functions. 相似文献
266.
Signal transduction mediated by heterotrimeric G proteins that couple to heptahelical receptors requires the involvement of many different proteins. Although some of the early evidence suggested that signal transduction components were assembled into complexes, much of the data supported an alternative hypothesis positing that the process involved transient interactions driven by random collision events. However, recent data indicate that many of the components involved in signal transduction do indeed form complexes. Here we review the evidence for these complexes and how they contribute to the specificity and efficiency of signaling in cells that must manage numerous signal transduction pathways. 相似文献
267.
The kinetics of phase redistribution in the (Mo, W)Si2 Nb system at 1500-1800°C was investigated. The kinetic parameters for growth of the lower silicides (Mo, W, Nb) 5Si3 + Nb5Si3 and decrease in the layer thickness of the higher silicide (Mo, W)Si2 as function of the oxidation temperature were determined. It was established that the stability of the multiphase and multicomponent system was more than twice that of the system MoSi2 Nb, and 15-18 times that of MoSi2 Mo. 相似文献
268.
One of the important issues related to world cities studies is the lack of systematic measurement of the formation of world cities. Such a measurement technique would be a useful tool for cities aspiring to attain world city status, especially those cities in Pacific Asia, such as Hong Kong, Singapore, Seoul, and Shanghai. This paper approaches this task by devising a measurement methodology based on quantifiable indicators to generate a World City Index and then uses Shanghai as a case study to test how the city stands compared to 32 current and potential world cities.
This paper is a part of the result of the research projects sponsored by the Chinese Academy of Sciences and the National Science Foundation of China with project numbers KZCX2-307 and 40171036. 相似文献
269.
We introduce a diffused optical detection system based on the administration of a fluorophore-antibody conjugate to diseased tissue. The conjugate interacts with the antigens expressed by the diseased tissue, resulting in fluorescent labeling of the antigen. By combining an optical detection system with a reconstruction algorithm developed on the basis of the random-walk model, we were able to determine the position of the fluorophore (and, thus, of the diseased cells) in the tissue. We present three-dimensional reconstructions of the location of a fluorophore (FITC-fluorescein isothiocyanate) in the tongues of mice. Measurements were performed with the fluorophore embedded at various simulated depths. The simulations were performed with agarose-based gel slabs applied to the tongue as tissuelike phantoms. Reconstructed fluorophore locations agree well with the actual values. 相似文献
270.
Madonna AJ Voorhees KJ Taranenko NI Laiko VV Doroshenko VM 《Analytical chemistry》2003,75(7):1628-1637
A novel approach to microbial detection using atmospheric pressure matrix-assisted laser desorption/ionization with an ion trap mass spectrometer to analyze whole cell bacteria is introduced. This new approach was tested with lyophilized spores and cultures of Bacillus globigii (BG) grown on agar media for 4 days or longer. At each stage of growth, it was found that biomarkers, identified as cyclic lipopeptides known as fengycin and surfactin, could be detected by pulsed ultraviolet laser irradiation of intact BG cells (approximately 5 mg) cocrystallized with alpha-cyano-4-hydroxycinnamic acid. Furthermore, definitive amino acid sequence information was obtained by performing tandem mass spectrometry on the precursor ions of the cyclic lipopeptides. The investigation was broadened to include the examination of aerosolized BG spores collected from the atmosphere and directly deposited onto double-sided tape. Subsequent analysis of the recovered spores resulted in the production of mass peaks consistent with fengycin. Other Bacillus species were analyzed for comparison and showed mass spectral peaks also identified as originating from various cyclic lipopeptides. Further studies were conducted using a pulsed infrared laser as the excitation source to analyze BG cells (approximately 5 mg) suspended in a matrix of 0.03 M ammonium citrate and glycerol resulting in the production of ions characteristic of fengycin and surfactin. 相似文献