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81.
Olsen E Vogt G Veberg A Ekeberg D Nilsson A 《Journal of agricultural and food chemistry》2005,53(19):7448-7457
Dynamic headspace/gas chromatography-mass spectrometry (GC-MS), front-face fluorescence spectroscopy, and a gas-sensor array technique (electronic nose) have previously detected lipid oxidation in pork back fat or mechanically recovered poultry meat earlier than or at the same time as a sensory panel. The present study was focused on measurement of early lipid oxidation in a more complicated product (freeze-stored, smoked sausages with spices). During the storage time, formation of components contributing to rancid odor and flavor (e.g., hexanal and 1-penten-3-ol) could be monitored with dynamic headspace/GC-MS. The GC-MS data also showed a decrease in 2-furancarboxaldehyde, which could indicate loss of Maillard type components often associated with acidic or meat odor and flavor. The fluorescence spectra were difficult to interpret, probably due to the simultaneous influence from increasing levels of lipid oxidation products and loss of fluorescent Maillard or spice components. The gas-sensor array responses were dominated by signals from, e.g., spice and smoke compounds. 相似文献
82.
Olsen E Vogt G Ekeberg D Sandbakk M Pettersen J Nilsson A 《Journal of agricultural and food chemistry》2005,53(2):338-348
An analytical method that can detect low levels of oxidation in food earlier than a sensory panel would be a valuable tool for food manufacturers as well as research institutes. Two model matrixes, pork back fat and mechanically recovered poultry meat (MRPM), were freeze-stored in air at -20 degrees C for 26 weeks. Peroxide value, thiobarbituric acid reactive substances, volatiles analyzed with dynamic headspace gas chromatography-mass spectrometry (GC-MS) and a gas-sensor array technique (electronic nose), chemiluminescence, and front-face fluorescence were evaluated against sensory analysis with regard to detection of early oxidation and correlation with sensory data. Fluorescence and GC-MS could detect oxidative changes in pork back fat earlier than the sensory panel and the electronic nose at the same time. The three methods were highly correlated with sensory attributes (r = 0.8-0.9). GC-MS gave the best results with regard to detection of small oxidative changes in MRPM. 相似文献
83.
Parakeratosis was diagnosed in 9 Shorthorn beef calves over a 4-year period. When pedigrees of these calves were analyzed, familial associations were strong. Thirty-six coefficients of relationship among all possible combinations of the 9 affected calves ranged from 0.5 to 39.8% and averaged 15.6%. All affected calves were descendants of bull A. Of 9 affected calves, 6 had bull A in their paternal and maternal pedigrees. The 3 remaining affected calves had bull A in their sire's pedigree and were born to 2 full-sib dams. Seemingly, parakeratosis in this Shorthorn herd was hereditary with the mode of inheritance being that of a simple autosomal recessive. 相似文献
84.
Rhenium heptafluoride, ReF(7), is one of only two stable binary compounds MX(7) with a heptacoordinated metal atom M and halide atom X. Its low-temperature crystal structure, as determined by high-resolution powder neutron diffraction, reveals the molecular structure, which has been the subject of speculation and debate for many years. Here it is shown within experimental error that at 1.5 kelvin the lowest energy configuration of ReF(7) has symmetry Cs (m) and is a distorted pentagonal bipyramid. The deviation of the two axial Re-F bonds from collinear and the puckering of the ring of equatorial fluorine atoms are similar to what has been postulated as one of the conformations of the pseudorotational motion observed at higher temperatures. 相似文献
85.
Human proto-oncogene c-jun encodes a DNA binding protein with structural and functional properties of transcription factor AP-1 总被引:231,自引:0,他引:231
D Bohmann T J Bos A Admon T Nishimura P K Vogt R Tjian 《Science (New York, N.Y.)》1987,238(4832):1386-1392
86.
Stein R Nam SI Schubert C Vogt C Futterer D Heinemeier J 《Science (New York, N.Y.)》1994,264(5159):692-696
Oxygen isotope records of cores from the central Arctic Ocean yield evidence for a major influx of meltwater at the beginning of the last deglaciation 15.7 thousand years ago (16,650 calendar years B.C.). The almost parallel trends of the isotope records from the Arctic Ocean, the Fram Strait, and the east Greenland continental margin suggest contemporaneous variations of the Eurasian Arctic and Greenland (Laurentide) ice sheets or increased export of low-saline waters from the Arctic within the East Greenland Current during the last deglaciation. On the basis of isotope and carbon data, the modern surface- and deep-water characteristics and seasonally open-ice conditions with increased surface-water productivity were established in the central Arctic at the end of Termination lb about 7.2 thousand years ago or 6,000 calendar years B.C.). 相似文献
87.
Abramovici A Althouse WE Drever RW Gürsel Y Kawamura S Raab FJ Shoemaker D Sievers L Spero RE Thorne KS Vogt RE Weiss R Whitcomb SE Zucker ME 《Science (New York, N.Y.)》1992,256(5055):325-333
The goal of the Laser Interferometer Gravitational-Wave Observatory (LIGO) Project is to detect and study astrophysical gravitational waves and use data from them for research in physics and astronomy. LIGO will support studies concerning the nature and nonlinear dynamics of gravity, the structures of black holes, and the equation of state of nuclear matter. It will also measure the masses, birth rates, collisions, and distributions of black holes and neutron stars in the universe and probe the cores of supernovae and the very early universe. The technology for LIGO has been developed during the past 20 years. Construction will begin in 1992, and under the present schedule, LIGO's gravitational-wave searches will begin in 1998. 相似文献
88.
89.
MIN‐SU LEE AH‐RA LEE MI‐AE JUNG IN‐HYE LEE JI‐HYE CHOI HYUN‐WOO CHUNG SOON‐WUK JEONG SANG‐SOEP NAHM KI‐DONG EOM 《Veterinary radiology & ultrasound》2010,51(6):670-673
We evaluated the whole body distribution of 2‐deoxy‐2‐[18F]fluoro‐d ‐glucose (18F‐FDG) in seven beagle dogs using positron emission tomography/computed tomography. The mean and maximum standard uptake values (SUV) for various tissues were computed. The SUV of the aortic blood pool was 0.65±0.19. Moderate uptake was present in brain (3.40±1.01). Mild uptake was present in orbital muscles, soft palate, laryngeal and pharyngeal region, mandibular salivary gland, myocardium, liver, pancreas, kidney, and intestine. 18F‐FDG uptake would be normally higher in these tissues because of normal physiologic activity. Mean and maximum SUV values of the eye, skeletal muscle, bone tissue, spleen, adrenal gland, stomach, tongue, gall bladder, and lung were similar to or lower than that of the aortic blood pool. These data provide a normal baseline for comparing pathologic 18F‐FDG uptake. 相似文献
90.
C. R. C. Sheppard M. Ateweberhan B. W. Bowen P. Carr C. A. Chen C. Clubbe M. T. Craig R. Ebinghaus J. Eble N. Fitzsimmons M. R. Gaither C‐H. Gan M. Gollock N. Guzman N. A. J. Graham A. Harris R. Jones S. Keshavmurthy H. Koldewey C. G. Lundin J. A. Mortimer D. Obura M. Pfeiffer A. R. G. Price S. Purkis P. Raines J. W. Readman B. Riegl A. Rogers M. Schleyer M. R. D Seaward A. L. S. Sheppard J. Tamelander J. R. Turner S. Visram C. Vogler S. Vogt H. Wolschke J. M‐C. Yang S‐Y. Yang C. Yesson 《水产资源保护:海洋与淡水生态系统》2012,22(2):232-261
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