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991.
Alterations in Fatty Acid Composition of Lipid Fractions from Potatoes During Storage Fatty acid composition of total lipids of the lecithin and cephalin fractions were determind by gas chromatography in samples of fresh potatoes and those stored for 8 months in cold. Moreover, a method for isolation of the pure cephalin fraction is reported. In all the three fractions the percentage of linolenic acid increased during storage, whereas the content of linoleic acid decreased. Other fatty acids remained practically unchanged during the storage. An additional experiment in which powdered freeze-dried potatoes were stored under undesirable conditions showed, as expected, that the content of unsaturated fatty acids decreased strongly. The results are discussed. 相似文献
992.
Magdi M. Mossoba Martin P. Yurawecz John A. G. Roach Hubert S. Lin Richard E. McDonald Brent D. Flickinger Edward G. Perkins 《Journal of the American Oil Chemists' Society》1995,72(6):721-727
Gas chromatography (GC)-electron ionization mass spectrometry of 2-alkenyl-4,4-dimethyl-oxazoline derivatives was used to
confirm the identities of a complex mixture of C18 diunsaturated cyclic fatty acid monomers (CFAMs) that were isolated from heated flaxseed (linseed) oil. The positions of
double bonds and 1,2-disubstituted unsaturated 5- and 6-membered rings along the fatty acid hydrocarbon chains were established
by this method. The oxazoline spectra exhibited a homologous ion series with a pattern of peaks that were 14 u (u=atomic mass
unit) apart but interrupted when a double bond (12-u mass interval) or a ring was present along the fatty acid chain. The
identity and location of a ring were indicated by a large interval of 68, 82, 66, 80, 78, or 120 u for a saturated 5- or 6-membered
ring, monounsaturated 5- or 6-membered ring, diunsaturated 6-membered ring, or monounsaturated bicyclic ring system (fused
5- and 6-membered rings), respectively. The double bond configuration for the methyl ester derivatives of these CFAMs was
established by GC-matrix isolation-Fourier transform infrared spectroscopy. The elucidated alkenyl structures at C2 in diunsaturated 2-[alkenyl]-4,4-dimethyloxazolines were 8-(2-but-trans-1-enyl-cyclopentenyl)octyl, 9-(2-propyl-cyclopentenyl)non-rans-8-enyl, 9-(2-propyl-cyclopentenyl)non-cis-7-enyl, 8-(2-but-cis-1-enyl-cyclopentenyl)ocytl, 9-(2-propylcyclopentenyl)non-cis-8-enyl, 8-(2-propyl-cyclohex-cis-4-enyl)oct-trans-7-enyl, 8-(prop-trans-1-enyl-cyclohex-cis-4-enyl)ocytl, and 8-(2-propylcyclohexa-cis,cis-3,5-dienyl)octyl.
Physical science aide, 1991–1992; currently a medical student at the University of Maryland, Baltimore, MD. 相似文献
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995.
Katarzyna Sokiewicz Monika Kacperczyk Hubert Krotkiewski Marcin Jdryka Ewa Maria Kratz 《International journal of molecular sciences》2022,23(15)
Endometriosis is a gynecological disease, the pathogenesis of which seems to be directly related to inflammatory processes with an immune basis. Our study aimed to analyze the O-glycosylation of native serum IgG and IgG isolated from sera of women with advanced endometriosis, without endometriosis but with benign gynecological diseases, and from a control group of healthy women, in the context of its utility for differentiation of advanced endometriosis from the other two groups of women studied. For the analysis of serum IgG O-glycosylation and the expression of multi-antennary N-glycans, lectin-ELISA with lectins specific to O-glycans (MPL, VVL, and Jacalin) and highly branched N-glycans (PHA-L) was used. The relative reactivities of isolated serum IgG O-linked glycans with specific lectins as well as the MPL/VVL O-glycosylation ratio were significantly higher in patients with advanced endometriosis and those with other gynecological diseases when compared to the control group of healthy women. We also showed significantly higher expression of PHA-L-reactive multi-antennary N-glycans in isolated IgG in the advanced endometriosis and the non-endometriosis groups in comparison to the control group. Additionally, significantly higher expression of Jacalin-reactive O-glycans in isolated IgG was observed in the non-endometriosis than in the advanced endometriosis group. The results of the ROC curve and cluster analysis additionally confirmed that the lectin-based analysis of isolated serum IgG O-glycosylation and the expression of highly branched N-glycans may help distinguish women with advanced endometriosis from healthy women. Moreover, the analysis of the expression of Jacalin-reactive i-IgG O-glycans may be helpful in differentiation between women with advanced endometriosis and patients with other gynecological diseases with an inflammatory background. In the case of non-endometriosis patients, the observed differences were most probably caused by increased expression of core 3 type O-glycans. 相似文献
996.
Tomasz Charytoniuk Hubert Zywno Klaudia Berk Wiktor Bzdega Adrian Kolakowski Adrian Chabowski Karolina Konstantynowicz-Nowicka 《International journal of molecular sciences》2022,23(6)
Rapidly increasing worldwide prevalence of obesity and related pathologies encompassing coronary heart disease, hypertension, metabolic syndrome, or type 2 diabetes constitute serious threats to global health and are associated with a significantly elevated risk of premature death. Considering the enormous burden of these pathologies, novel therapeutic and preventive patterns are indispensable. Dysregulation of one of the most complex biological systems in the human body namely, the endocannabinoid system (ECS) may result in metabolic imbalance and development of insulin resistance, type 2 diabetes, or non-alcoholic fatty liver disease. Furthermore, many studies showed that physical exercises, depending on their type, intensity, and frequency, exert various alterations within the ECS. Emerging evidence suggests that targeting the ECS via physical activity may produce robust beneficial effects on the course of metabolic pathologies. However, the data showing a direct correlation between the ECS and physical activity in the aspect of metabolic health are very scarce. Therefore, the aim of this review was to provide the most up-to-date state of knowledge about the interplay between the ECS activity and physical exercises in the novel therapeutic and preventive approach toward metabolic pathologies. We believe that this paper, at least in part, will fulfill the existing gap in knowledge and encourage researchers to further explore this very complex yet interesting link between the ECS, its action in physical activity, and subsequent positive outcomes for metabolic health. 相似文献
997.
998.
Hubert Monnier Neïla MhiriLaurent Falk 《Chemical Engineering and Processing: Process Intensification》2010
Increasing mass transfer efficiencies is reached in G/L absorption contactors thanks to stabilization of the liquid flow. Hydrodynamic studies about the stability of a liquid film thickness are carried out to explain variations of mass transfer efficiencies during absorption experiments. These studies are based on the analytical expression developed by Hobler (1964) [1] which enables to predict the minimum wetting rate (MWR) and the minimum liquid film thickness (MLFT). Experiments were carried out to validate the prediction of the hydrodynamic model for a specific chemical system (absorption of tetrachloroethylene in di-ethyl-hexyl adipate). Therefore, two microstructured plates have been investigated in comparison to an unstructured plate. The plates have been embedded in a miniaturized falling film absorber. A strong influence of the geometry on the mass transfer efficiency is found, especially at low liquid flow rates where dry zones decrease the interfacial specific area which differs from the specific surface of the solid support. 相似文献
999.
Cyril Vuillecard Charles Emile Hubert Rgis Contreau Anthony mazzenga Pascal Stabat Jerome Adnot 《Energy》2011,36(5):2912-2923
To face winter electricity peaking issues the authors proposes an analysis of the potential of distributed gas technologies for demand side management. This impact has to be analysed at small scale before any large scale extrapolation. Bi-energy technologies (gas and electricity) are a path to transfer loads from one system to another. Indeed, the flexible gas infrastructure adapts to load while electricity demand variations cause risk of black-out. The impacts of two hybrid technologies are studied at transformer level with 1-min experimental load profiles of 40 dwellings equipped with micro Combined Heat and Power (μCHP) boilers over a year in France. An absolute peak load reduction by 17% at small scale is found. Different technology mixes are then simulated to assess the effect on local infrastructure. Finally a methodology for temperature dependence analysis of load is used to assess different potential benefits of gas technologies. 相似文献
1000.
Comparative study between platinum supported on carbon and non-noble metal cathode catalyst in alkaline direct ethanol fuel cell (ADEFC) 总被引:1,自引:0,他引:1
Mohammad Zhiani Hubert A. Gasteiger Michele Piana Stefano Catanorchi 《International Journal of Hydrogen Energy》2011,36(8):5110-5116
In this study, we reported a comparison study between the performance of the commercial non-noble metal cathode electrode (made by Hypermec™ K14 catalyst - provided by Acta S.p.A.) and cathode electrode containing 10 wt% Pt/C, in the alkaline direct ethanol fuel cell (ADEFC) under different conditions.Further electrochemical investigations have been done by RDE and driven mode cell to compare the intrinsic activity and selectivity of 10 wt% Pt/C and Hypermec™ K14 transition metals cathode catalysts. It is worthwhile to point out that Hypermec™ K14 cathode catalyst shows a remarkable selectivity to oxygen reduction and it has a superior intrinsic activity in oxygen reduction reaction (ORR) especially in terms of volumetric current density (A/cm3). Test results of active DEFC made by non-noble cathode catalyst showed superior performance compared to the cell made by 10 wt% Pt/C cathode catalysts in terms of power density and OCV at 60 °C and ambient pressure. This result is related to the higher ORR kinetic of non-noble metal cathode catalyst in alkaline media. 相似文献