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31.
In this study we examined the lymphatic transport in rats of FA after administration of interesterified oils containing CLA, with emphasis on the location of CLA and octanoic acid in the TAG. The oils were produced by enzymatic interesterification. Eight oils with different structures or FA profiles were examined in this study: MCM, CMC, OCO, and COC, where M was expected to be octanoic acid and O oleic acid. In group 1, C was CLA as a mixture of the two CLA isomers c9, t11 or t10, c12, and in group 2, C was mainly the isomer t10, c12. Rats were subjected to cannulation of the mesenteric lymph duct, and the following day they were intragastrically administered one of the oils and lymph samples were collected for 24 h. The lymphatic transport of total FA from 0 to 8 h in group 1 was significantly (P < 0.05) higher for the OCO-1 and the COC-1 oils than for the CMC-1 oil. Similarly, in group 2 the transport was higher for the OCO-2 oil than for the CMC-2 oil. The recovery of both of the CLA isomers examined was similar (50-70%) and independent of the isomer, oil structure, and FA profile, whereas more octanoic acid was recovered from the CMC oils than from the MCM oils. The results indicated that the FA profiles and the position of octanoic acid had only a minor influence on the absorption of CLA. 相似文献
32.
Host Plant Volatiles Synergize Response to Sex Pheromone in Codling Moth, Cydia pomonella 总被引:1,自引:0,他引:1
Plant volatile compounds synergize attraction of codling moth males Cydia pomonella to sex pheromone (E,E)-8,10-dodecadien-1-ol (codlemone). Several apple volatiles, known to elicit a strong antennal response, were tested in a wind tunnel. Two-component blends of 1 pg/min codlemone and 100 pg/min of either racemic linalool, (E)-beta-farnesene, or (Z)-3-hexen-1-ol attracted significantly more males to the source than codlemone alone (60, 58, 56, and 37%, respectively). In comparison, a blend of codlemone and a known pheromone synergist, dodecanol, attracted 56% of the males tested. Blends of pheromone and plant volatiles in a 1:100 ratio attracted more males than 1:1 or 1:10,000 blends. Adding two or four of the most active plant compounds to codlemone did not enhance attraction over blends of codlemone plus single-plant compounds. Of the test compounds, only farnesol was attractive by itself; at a release rate of 10,000 pg/min, 16% of the males arrived at the source. However, attraction to a 1:10,000 blend of codlemone and farnesol (42%) was not significantly different from attraction to codlemone alone (37%). In contrast, a codlemone mimic, (E)-10-dodecadien-1-ol, which attracted 2% males by itself, had a strong antagonistic effect when blended in a 1:10,000 ratio with codlemone. 相似文献
33.
We have studied the effect of the amount Φc of a reactive compatibilizer on the rheological properties of a polyethylene/polyamide blend, under steady shear and transient extensional flows. Here, we propose to describe the viscosity η(γ) and the first normal stress coefficient γ1(γ) using a Carreau‐type power‐law model, which is a three‐parameter model. A single model is sufficient to express the behavior of γ1(γ) On the other hand, the complete η(γ) curve is described by the superposition of two Carreau models, in relation to the presence of two relaxation mechanisms. Moreover, the extentional viscosity ηE(?), estimated using the end pressure drop observed in capillary flow experiments, is expressed by a two‐parameter power‐law model. 相似文献
34.
Said Ghaout Alain Louveaux Anne Marie Mainguet Max Deschamps Youssef Rahal 《Journal of chemical ecology》1991,17(8):1499-1515
A field study of the food eaten by solitary desert locusts was carried out in a winter breeding area in Mauritania. The food eaten, determined by the plant epidermis found in fecal pellets, was compared to the plant's availability in the habitat.Schouwia purpurea, well represented in the diets, was dominant at the study site. Adults had a preference forTribulus terrester. Growth and feeding on these two plants were compared. The high water content ofS. purpurea leaves limited the dry matter eaten and slowed down growth. Glucosinolates were separated and quantified by gas chromatography. There are 132mol/g dry matter in green leaves. In multiple choice tests, with paper disks, glucosinolate extracts were phagostimulant at a low concentration (21mol/g dry matter) and repulsive at a higher one (214mol/ g dry matter). Biting behavior onS. purpurea was recorded and analyzed on video. The importance ofSchouwia purpurea in desert locust habitats and its defenses is discussed. 相似文献
35.
Caroline Fauquant Valrie Briard Nadine Leconte Marie‐Caroline Michalski 《European Journal of Lipid Science and Technology》2005,107(2):80-86
The aim of this study was to characterize the fatty acid composition of the core and membrane of differently sized milk fat globules separated by microfiltration, which can now be used to manufacture dairy products. Native milk fat globules of various mean diameters, ranging from d43 = 2.3 µm to 8.0 µm, were obtained using microfiltration of raw whole milk. After milk fat globule washing, the milk fat globule membrane (MFGM) and the triglyceride core (TC) were separated by manual churning. After total lipid extraction from each fraction, their fatty acid composition was characterized using methyl ester analysis by gas chromatography. Regardless of season, no significant differences were observed in the fatty acid composition of the MFGM phospholipids. Conversely, significant differences were found in the fatty acid composition of TC; particularly, small fat globule TC contained more medium‐chain fatty acids and less stearic acid than large fat globule TC. These results show that the previously observed differences in total fatty acid composition among differently sized milk fat globules are due to their triglyceride composition and MFGM amount rather than to the composition of the MFGM. 相似文献
36.
In this paper, we show that large connected slip patches (hydrophobic patches) are a necessity to induce macroscopic slip effects of water flow in microchannels. For this purpose, the 2D fluid flow between a planar stationary surface with alternating stick and slip patches and a parallel planar surface moving with a constant relative velocity has been studied by computer simulations based on Navier–Stokes equations. A slip patch is defined as the slipping length in a 2D system or a slip area of the surface in a 3D system. The simulations reveal that the ratio (size of each slip patch)/(distance between the two parallel interfaces) has profound effect on the viscous stress on the moving surface when this ratio is around and above one. However, when the ratio is much below one, the effect of the slip patches are minor, even if the area fraction of slip patches are higher than 50 %. Obviously, the stick patches adjacent to the slip patches act as effective barriers, preventing the fluid velocity to increase near the surface with alternating stick and slip patches. The obtained results are scalable and applicable on all length scales, with an exception for narrow channels in the subnano regime, i.e. <1 nm where specific effects as the atomistic composition and the nanostructure of the wall as well as the interactions between the wall and the water molecules have an effect. 相似文献
37.
Dynamic mechanical analysis and differential scanning calorimetry were used to investigate the relaxations and crystallization of high‐density polyethylene (HDPE) reinforced with calcium carbonate (CaCO3) particles and an elastomer. Five series of blends were designed and manufactured, including one series of binary blends composed of HDPE and amino acid treated CaCO3 and four series of ternary blends composed of HDPE, treated or untreated CaCO3, and a polyolefin elastomer [poly(ethylene‐co‐octene) (POE)] grafted with maleic anhydride. The analysis of the tan δ diagrams indicated that the ternary blends exhibited phase separation. The modulus increased significantly with the CaCO3 content, and the glass‐transition temperature of POE was the leading parameter that controlled the mechanical properties of the ternary blends. The dynamic mechanical properties and crystallization of the blends were controlled by the synergistic effect of CaCO3 and maleic anhydride grafted POE, which was favored by the core–shell structure of the inclusions. The treatment of the CaCO3 filler had little influence on the mechanical properties and morphology. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3907–3914, 2007 相似文献
38.
Belletier Clément Charkhabi Morteza Pires de Andrade Silva Gustavo Ametepe Kevin Lutz Mathieu Izaute Marie 《Cognition, Technology & Work》2021,23(1):103-116
Cognition, Technology & Work - Rapid technological innovations are constantly influencing the complexification and automatization of the work lines pushing human operators to use diverse... 相似文献
39.
40.
This paper outlines the major motivating factors concerning a novel collaborative project between Edinburgh College of Art and Edinburgh Virtual Environment Centre. The Tacitus project will investigate the use of multi-modal virtual environments, specifically, the haptic (touch) modality, with regards to the creative processes employed by designers working within the field of applied arts. The salient areas of research are described, and the methods by which information regarding these areas will be obtained are considered. Initial investigations have revealed a strong need to mimic the traditional applied artists' workspaces, with co-location of visual and haptic cues a priority. 相似文献