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Helle Lindberg Madsen Lotte Andersen Luise Christiansen Per Brockhoff Grete Bertelsen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,203(4):333-338
The sensory intensity measured as theabsolute threshold value of spice andrecognition of spice was evaluated for summer savory and rosemary in meat balls. The values forabsolute threshold value of spice were found to be significantly lower for rosemary than for summer savory. The antioxidative activity of the spices was analysed in two accelerated model systems and in a storage experiment. In one of the model systems, oxidation was accelerated by heat and by an elevated pressure of oxygen. Both spices significantly improved the oxidative stability of the meat balls in this model system. In the second model system metal catalyst oxidation in a meat slurry was used and a reduction in the oxidative processes in samples containing the spices was again shown. In both model systems a slightly higher antioxidative activity was seen for rosemary compared to summer savory. In the storage experiment, the spices were added at a sensorially acceptable level and the heat-treated meat balls were stored at 5°C. A significant reduction in the development of warmed-over flavour (WOF) caused by the addition of spices was measured by a reduction in 2-thiobarbituricacid-reactivesubstances (TBARS) and in hexanal. A reduction in TBARS of approximately 30% in meat balls containing added spices was seen independently of packaging in 1% oxygen or in atmospheric air and the reduction (30%) was constant throughout the storage period. 相似文献
24.
X Zhu Y Rouille NS Lamango DF Steiner I Lindberg 《Canadian Metallurgical Quarterly》1996,93(10):4919-4924
The neuroendocrine protein 7B2 contains two domains, a 21-kDa protein required for prohormone convertase 2 (PC2) maturation and a carboxyl-terminal (CT) peptide that inhibits PC2 at nanomolar concentrations. To determine how the inhibition of PC2 is terminated, we studied the metabolic fate of the 7B2 CT peptide in RinPE-7B2, AtT-20/PC2-7B2, and alphaTC1-6 cells. Extracts obtained from cells labeled for 6 h with [3H]valine were subjected to immunoprecipitation using an antibody raised against the extreme carboxyl terminus of r7B2, and immunoprecipitated peptides were separated by gel filtration. All three cell lines yielded two distinct peaks at about 3.5 kDa and 1.5 kDa, corresponding to the CT peptide and a smaller fragment consistent with cleavage at an interior Lys-Lys site. These results were corroborated using a newly developed RIA against the carboxyl terminus of the CT peptide which showed that the intact CT peptide represented only about half of the stored CT peptide immunoreactivity, with the remainder present as the 1.5-kDa peptide. Both peptides could be released upon phorbol 12-myristate 13-acetate stimulation. We investigated the possibility that PC2 itself could be responsible for this cleavage by performing in vitro experiments. When 125I-labeled CT peptide was incubated with purified recombinant PC2, a smaller peptide was generated. Analysis of CT peptide derivatives for their inhibitory potency revealed that CT peptide 1-18 (containing Lys-Lys at the carboxyl terminus) represented a potent inhibitor, but that peptide 1-16 was inactive. Inclusion of carboxypeptidase E (CPE) in the reaction greatly diminished the inhibitory potency of the CT peptide against PC2, in line with the notion that the CT peptide cleavage product is not inhibitory after the removal of terminal lysines by CPE. In summary, our data support the idea that PC2 cleaves the 7B2 CT peptide at its internal Lys-Lys site within secretory granules; deactivation of the cleavage product is then accomplished by CPE, thus providing an efficient mechanism for intracellular inactivation of the CT peptide. 相似文献
25.
Chr. Bargholtz L. Gerén V. N. Grebenev Yu. B. Gurov V. S. Karpukhin I. V. Laukhin K. Lindberg V. G. Sandukovsky P. -E. Tegnér B. A. Chernyshev R. R. Shafigullin 《Instruments and Experimental Techniques》2006,49(3):306-313
The parameters of a spectrometer for searching for deeply bound pionic states of xenon are presented. The main component of the spectrometer is a multilayer semiconductor telescope based on high-purity germanium detectors. A technique for calibrating the spectrometer and measuring its energy resolution using reactions p(d, 3He)π0 and 14N(d, 3He)13C is described. The energy resolution of the setup is shown to be 0.85 MeV for 3He ions with an energy of ~360 MeV. 相似文献
26.
The specific heat, Cp, was determined by DSC on a series of resol-type phenol formaldehyde resins with varying phenol formaldehyde molar ratio. The extrapolated Cp values at 25°C vary between 1.181-1.206 kJ · kg?1 K?1 and the dCp/dT ratio was found to be 0.0042kJ · kg?1K?2 in the temperature range of 70–125°C. 相似文献
27.
对连续过程工业实施CIMS总体技术方案作了较为深入的探讨,并对天津市轧三制钢有限公司实施CIMS总体方案及技术路线进行了详细介绍。 相似文献
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The detectability of wavelength-modulation (WM) diode-laser spectrometric techniques is frequently limited by various background signals. A new theoretical formalism for WM spectrometry, based on Fourier analysis and therefore capable of handling a variety of phenomena including the characterization and the analysis of analytical as well as background WM signals, was recently presented [Appl. Opt. 38, 5803 (1999)]. We report a detailed characterization of WM background signals from multiple reflections between pairs of surfaces in the optical system that act as etalons and from the associated intensity modulation in terms of this new formalism. The agreement between the background signals from a thin glass plate and those predicted by the formalism is good, which verifies the new Fourier analysis-based formalism. 相似文献
30.
CHEOL LAE ROH MOON NO LEE MYUNG JIN CHUNG 《International journal of systems science》2013,44(4):419-424
In this paper we propose a design method of an iterative learning controller (ILC) for a non-minimum phase (NMP) system by model-matching theory. The ILC consists of two learning filters acting on both the previous input signal and the previous error signal. To design the learning filters, we convert the convergence condition of the ILC into the model-matching problem and get the stable and proper learning filter by solving the Nevanlinna's algorithm. To show the usefulness of the proposed algorithm, some design examples are included. 相似文献