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1.
Pure cardiolipins (1,3-diphosphatidylglycerol) were prepared from mitochondria of heart, liver and kidney from 21-day-old
male Wistar rats and submitted toNaja naja venom phospholipase A2 (EC 3.1.1.4) action. Incubation conditions were controlled carefully, and a complete hydrolysis of cardiolipin to lysocardiolipin
{di [1 (1″) acylsn-glycero-3-phosphoryl] 1′, 3′-sn-glycerol} and fatty acids from positions 2 (2″) was obtained in less than two hr practically without side reactions. Cardiolipins
from the three organs contained low levels of saturated fatty acids; stearic acid accounted for 0.4–0.7% and palmitic acid
for 1.4–3.5% of total fatty acids. These percentages apparently depended on the organ. In all three cases, linoleic acid was
the major component, but its percentage varied from 62–78% of total fatty acids. Acyl chains linked to positions 1 (1″) of
all three cardiolipin preparations exhibited a similar pattern; they were composed of linoleic acid for 85–89%. This fatty
acid also was the main component esterified at position 2 (2″), but its percentage was much more variable: from 39.8% in heart
to 51.2% in kidney and 67.8% in liver mitochondria. The remaining acids comprised octadecenoic and polyunsaturated fatty acids
with more than 18 carbon atoms in different proportions. As opposed to other phospholipids,cis-vaccenic acid, and not oleic acid, was the main octadecenoic acid present in cardiolipins.
Octadecenoic acids were nine- to 10-fold more concentrated at positions 2 (2″) than at positions 1 (1″). The percentage ofcis-vaccenic acid was four- to five-fold higher than that of oleic acid at positions 2 (2″), whereas oleic acid dominated at
positions 1 (1″). From results presented in this study and selected literature data, it may be concluded that fatty acids
are asymmetrically distributed in cardiolipins of different origins, with linoleic acid showing a definite preference for
position 1 (1″). 相似文献
2.
Off-Site Exposure to Respirable Aerosols Produced during the Disk-Incorporation of Class B Biosolids
Swee Yang Low Tania Paez-Rubio Carolina Baertsch Matthew Kucharski Jordan Peccia 《Canadian Metallurgical Quarterly》2007,133(10):987-994
Field experiments were conducted at a Class B biosolids land application site in central Arizona to measure, model, and source-track the off-site transport of aerosols emitted when biosolids were disk-incorporated into soils. Real-time PM10 monitoring provided time-resolved aerosol information sufficient for verifying both off-site concentration and off-site exposure time model results. Under the conditions considered and at a distance of 165?m from the aerosol source, biosolids disk-incorporation resulted in an intermittent exposure to biosolids-derived aerosol concentration between 15 and 40?μg/m3 and an inhalable biosolids dose between 2 and 8?μg. Transport modeling predicted that these doses will decrease with increasing wind speed. In addition, three DNA sequence-based biosolids source tracking methods were applied to aerosol samples and confirmed the presence of biosolids in aerosols at 5, 65, and 165?m from the aerosol source. Field measurements and modeling indicate that the nature of biosolids-derived aerosol exposure is a series of intermittent high concentration puffs, rather than a continuous low concentration. 相似文献
3.
Reliable Computing - 相似文献
4.
Flávio A. Pavan Sidinei A. Gobbi Celso C. Moro Tania M.H. Costa Edilson V. Benvenutti 《Journal of Porous Materials》2002,9(4):307-311
Anilinepropylsilica hybrid powder was synthesized by a sol-gel route in basic medium using HF as catalyst. The effect of the amount of HF catalyst on the morphologies and on organic content was studied. The xerogels were characterized using FTIR, SEM and N2 adsorption-desorption isotherms. The increase in the HF quantity results in an slight increase in organic content and changes in the particle size, surface area and pore structure. 相似文献
5.
A time-domain test for some types of nonlinearity 总被引:1,自引:0,他引:1
The bispectrum and third-order moment can be viewed as equivalent tools for testing for the presence of nonlinearity in stationary time series. This is because the bispectrum is the Fourier transform of the third-order moment. An advantage of the bispectrum is that its estimator comprises terms that are asymptotically independent at distinct bifrequencies under the hypothesis of linearity. An advantage of the third-order moment is that its values in any subset of joint lags can be used in the test, whereas when using the bispectrum the entire (or truncated) third-order moment is required to construct the Fourier transform. We propose a test for nonlinearity based upon the estimated third-order moment. We use the phase scrambling bootstrap method to give a nonparametric estimate of the variance of our test statistic under the hypothesis. Using a simulation study, we demonstrate that the test obtains its target significance level, with large power, when compared to an existing standard parametric test that uses the bispectrum. Further we show how the proposed test can be used to identify the source of nonlinearity due to interactions at specific frequencies. We also investigate implications for heuristic diagnosis of nonstationarity. 相似文献
6.
M Abele-Horn C Wolff P Dressel A Zimmermann W Vahlensieck F Pfaff G Ruckdeschel 《Canadian Metallurgical Quarterly》1996,15(7):595-598
The efficiency of the polymerase chain reaction (PCR) was compared with that of culture for detection of Ureaplasma urealyticum and Mycoplasma hominis in 726 clinical specimens comprising 189 gynecological samples, 362 urological samples, and 175 samples from newborn infants. The sensitivity of PCR versus culture was 95% for both organisms, while the sensitivity of culture versus PCR was 91% for Ureaplasma urealyticum and 84% for Mycoplasma hominis. Furthermore, PCR tests were faster than culture tests, allowing the time to diagnosis to be reduced from two to five days to 24 h. 相似文献
7.
Effects of dietary trielaidin upon the alkenyl chain profile of plasmalogens were studied using heart mitochondria of rats
fed a semi-purified diet containing 10% of fat supplement in which elaidic acid accounted for 69% of total fatty acids. Alkyl
substituted dioxane (ASD) derivatives of the alkenyl groups of plasmalogens were prepared and analyzed by silver nitrate TLC
and by GLC on different phases (BDS and OV-275). After two months of feeding the experimental diet, 40% of the ASD contained
atrans-octadecenyl chain, suggesting that dietary elaidic acid was reduced in vivo to the corresponding alcohol and incorporated
into plasmalogens. There was a simultaneous decrease in the percentage of ASD containing saturated chains, but the percentage
of ASD substituted withcis-octadecenyl chains was not significantly affected. These observations suggested that elaidic acid may compete with saturated
fatty acids, but not withcis-octadecenoic acids during the plasmalogen biosynthesis. Feeding trielaidin did not seem to have any significant influence
on the relative proportions of plasmalogens, which accounted for 11–12%, on a phosphorus basis, of total heart mitochondria
phospholipids. 相似文献
8.
A novel and systematic method is presented for the complete determination of dyadic spectral Green's functions directly from Maxwell's equations. With the use of generalized scalarizations developed in this paper, four general and concise expressions for the spectral Green's functions for one-dimensionally inhomogeneous multilayer structures, excited by three-dimensional electric and magnetic current sources, are given in terms of modal amplitudes together with appropriate explicit singular terms at the source region. It is shown that Maxwell's equations in spectral-domain can be reduced, by using dyadic spectral eigenfunctions, to two sets of z-dependent inhomogeneous transmission-line equations for the modal amplitudes. One set of the transmission-line equations are due to the transverse current sources and the other set due to the vertical current sources. Utilizing these equations, network schematizations of the excitation, transmission and reflection processes of three-dimensional electromagnetic waves in one-dimensionally inhomogeneous multilayer structures are achieved in a full-wave manner. The determination of the spectral Green's functions becomes so simple that it is accomplished by the investigation of voltages and currents on the derived equivalent circuits. Examples of singleand multilayer structures are used to validate the general expressions and the equivalent circuits 相似文献
9.
Robert L. Wolff 《Journal of the American Oil Chemists' Society》1994,71(3):277-283
Twelve commercial samples of French butter, purchased in October–November, and 12 other samples, purchased in May–June, were
analyzed with particular attention to theirtrans-octadecenoic acid contents. The isomeric fatty acids were quantitated by a combination of gas-liquid chromatography (GLC)
of total fatty acids as isopropyl esters on a polar capillary column (CPSil 88) and of silver nitrate-impregnated thin-layer
chromatography followed by GLC of the pooled saturated (used as internal standards) andtrans-octadecenoic acid fractions. Autumn butters contained 3.22±0.44%trans-octadecenoic acids (relative to total fatty acids), whereas those collected during the spring contained 4.28±0.47% (P<0.01). Minimum and maximum values for the two sets of butters were 2.46 (autumn) and 5.10% (spring), respectively. The annual
mean value for thetrans-octadecenoic acid content in all butter samples was 3.8% of total fatty acids (ca. 2% for thetrans-11 18∶1 acid). This value allows calculation of the daily individual intake oftrans-octadecenoic acids from dairy products by populations of member states of the European Economic Community (EEC). It varies
from 0.57 g (Portugal) to 1.66 g (Denmark). The mean value for the twelve countries of the EEC is 1.16 g/person/d, which is
close to data published for the United States. In France, the consumption oftrans octadecenoic acids from dairy fat is higher than that from margarines (ca. 1.5 vs. 1.1 g/person/d). 相似文献
10.