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81.
Impacts of fat from ruminants' meat on cardiovascular health and possible strategies to alter its lipid composition
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Einar Vargas‐Bello‐Pérez Rafael E Larraín 《Journal of the science of food and agriculture》2017,97(7):1969-1978
In the last few decades there has been increased consumer interest in the fatty acid (FA) composition of ruminant meat due to its content of saturated FAs, which have been implicated in diseases associated with modern life. However, recent studies have questioned the recommendations to reduce intake of fat, saturated FAs and cholesterol as a means of reducing the risk of cardiovascular disease. Interestingly, ruminant meat has some bioactive lipids such as C18:1t11 and C18:2 c9, t11 which have been reported to have positive effects on human health. In order to improve muscle fat composition from a human health standpoint, oilseeds, plant oils and marine oils can be used in ruminant diets. On the other hand, molecular mechanisms play an important role in the alteration of the FA composition of muscle fat. Genetics offer a wide range of possibilities for improvement of muscle fat composition by identifying different loci underlying the expression of quantitative traits. While significant progress has been made in characterizing the influence of diet on the FA composition of ruminant meat, the use of genetic tools can favor genotypes that could maximize their genetic potential through the diet. © 2016 Society of Chemical Industry 相似文献
82.
Einar Whalen 《Rocks & Minerals》2013,88(4):245-248
Artsmithite, Hg1+ 4Al(PO4)2-x(OH)1+3x (where x = 0.26), occurs as a colorless-to-white matted nest (measuring 1 × 3 mm on the holotype specimen) of randomly scattered fibrous to acicular crystals at the Funderburk prospect, Pike County, Arkansas. The mineral is monoclinic, and individual crystals average 0.5 mm in length with a length-to-width ratio in excess of 100:1. Individual fibers are flexible and elongated along [001] and are colorless and transparent. Artsmithite is vitreous, has an off-white to cream-colored streak, shows no obvious cleavage, and displays an irregular fracture. It does not fluoresce, and its calculated density is 6.40g/cc. Optically, the mineral is biaxial positive with a 2V measured at 60 degrees and all indices of refraction exceeding 1.80; r < v, distinct; and the fibers are length slow with Z approximately equal to c. Associated minerals on the holotype specimen are quartz, goethite, dickite, and cinnabar; other species reported from the locality include barite, calcite, calomel, eglestonite, fluorapatite, galena, livingstonite, mercury, metacinnabar, montroydite, perhamite, pyrite, siderite, stibiconite, stibnite, and terlinguaite. Artsmithite is a secondary phase, probably produced during the weathering and chemical breakdown of cinnabar and fluorapatite (Roberts et al. 2003). 相似文献
83.
In January 2006 it was reported that Greenland halibut (Reinhardtius hippoglossoides) caught in the Barents Sea contained mercury levels that exceeded the EU's upper limit of 0.5 mg/kg wet weight for this species. To further investigate this finding, the National Institute of Nutrition and Seafood Research (NIFES) in Norway recently undertook a study to quantify the levels of mercury in Greenland halibut caught in the same area of the Barents Sea. A total of 120 Greenland halibut were caught in this area between the 28th and the 30th of January 2006. The fish were immediately frozen and shipped to the laboratory; individual fish were coded, weighed, defrosted, filleted and skinned before their mercury content was determined. Analyses were carried out on 65 individuals of Greenland halibut weighing from 0.81 kg to 7.1 kg, and 40 fish weighing more than 3 kg. The lowest mercury concentration found in muscle tissue (skinless and boneless fillet) was 0.019 mg/kg wet weight, in a fish that weighed 0.81 kg. The highest mercury concentration measured in muscle tissue was 1.1 mg/kg wet weight, from a fish that weighed 4.2 kg. Of the 65 fish analysed, 15 individuals with weight exceeding 3 kg had mercury concentrations in their muscle tissue exceeded the EU's upper limit. 相似文献
84.
WANGDong—cheng 《钢铁研究学报(英文版)》2012,19(6):19-24
The shortcomings of an exit stress variation formula which has been well accepted are analyzed; it is found that the exit stress variation formula violates the premise of the law of volume constancy. The shortcomings of an entry stress variation formula are analyzed too, and the basic assumption of the formula is uniform exit velocity. However, for a rigid-plastic material uniform exit velocity implies that the lateral distribution of elongation is uniform, so the exit stress must be uniform and any type of flatness defect is impossible, which is contrary to the practice. In fact, entry and exit velocity variation influence entry and exit stress variation, and entry and exit stress variation influence entry and exit velocity variation too, so a precise explicit stress variation formula cannot be got easily. Considering the relationship between stress variation and velocity variation, an iteration method is presented to calculate entry and exit stress variation of cold rolling strip. To avoid divergent phenomenon of the iteration course, a relaxation factor method is adopted. The calculation results are compared with the entry and exit stress variation formula commonly used by many researchers. The difference is remarkable, while the result calculated agree more well with measured result if the exit elastic recovery zone is considered. Specially, the incoming flatness′ propagate efficiency calculated gives a more realistic result. 相似文献
85.
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87.
Films of lanthanum tungstate, 3 μm in thickness, were fabricated by means of pulsed laser deposition on a Pd foil. The films were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and their electrical conductivity was measured at temperatures between 400 and 800 °C in different gas atmospheres. The films' structure and electrical characteristics are close to what is reported in the literature for corresponding polycrystalline material. The films exhibit fairly high proton conductivity at elevated temperatures, which make them interesting for components in hydrogen-related technologies. Changes in microstructure and the crystallographic orientation observed at higher temperatures were accompanied by changes in the conductivity characteristics. 相似文献
88.
Distributed systems are often modeled by objects that run concurrently, each with its own processor, and communicate by synchronous
remote method calls. This may be satisfactory for tightly coupled systems, but in the distributed setting synchronous external
calls lead to much waiting; at best resulting in inefficient use of processor capacity, at worst resulting in deadlock. Furthermore,
it is difficult to combine active and passive behavior in concurrent objects. This paper proposes an object-oriented solution
to these problems by means of asynchronous method calls and conditional processor release points. Although at the cost of
additional internal nondeterminism in the objects, this approach seems attractive in asynchronous or unreliable environments.
The concepts are integrated in a small object-oriented language with an operational semantics defined in rewriting logic,
and illustrated by examples.
This paper extends and combines results which have appeared in the proceedings of the 2004 International Conference on Software
Engineering and Formal Methods (SEFM) [37] and the 2004 International Workshop on Rewriting Logic and its Applications (WRLA)
[41]. 相似文献
89.
We discuss the numerical solution of partial differential equations in a particular class of three-dimensional geometries;
the two-dimensional cross section (in the xy-plane) can have a general shape, but is assumed to be invariant with respect to the third direction. Earlier work has exploited
such geometries by approximating the solution as a truncated Fourier series in the z-direction. In this paper we propose a new solution algorithm which also exploits the tensor-product feature between the xy-plane and the z-direction. However, the new algorithm is not limited to periodic boundary conditions, but works for general Dirichlet and
Neumann type of boundary conditions. The proposed algorithm also works for problems with variable coefficients as long as
these can be expressed as a separable function with respect to the variation in the xy-plane and the variation in the z-direction. For problems where the new method is applicable, the computational cost is very competitive with the best iterative
solvers. The new algorithm is easy to implement, and useful, both in a serial and parallel context. Numerical results demonstrating
the superiority of the method are presented for three-dimensional Poisson and Helmholtz problems using both low order finite
elements and high order spectral element discretizations. 相似文献
90.
Anne Lise Dons Einar K. Jensen Yngve Langsrud Egil Trømborg Stig Brusethaug 《Metallurgical and Materials Transactions A》1999,30(8):2135-2146
The model predicts the solidification path in the aluminum corner of the AlCuFeMgMnSi phase diagram, with compensation for
solid-state diffusion and particle growth undercoolings. Input is the composition and the rate of cooling. Output is the temperature
vs fraction solid; the solid-state concentration profiles; the type, volume fraction, and size of the intermetallic particles;
and also the temperature-dependent thermal conductivity, density, specific heat, and heat of fusion for use in thermal models. 相似文献