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31.
Claude Leger Lucie Fremont Didier Marion Ibrahim Nassour Marie-Françoise Desfarges 《Lipids》1981,16(8):593-600
This paper describes evidence of (n−3) and particularly of 22∶6 (n−3) fatty acid enrichment in trout lipoproteins as well
as in vitellogenin, egg lipovitellin and oil globule. Among the lipoproteins, HDL and LDL were the main forms of blood lipid
transport, whereas phospholipids and cholesteryl esters are the preferential chemical carriers for (n−3) fatty acid transport.
However, cholesteryl esters were less important as esterified fatty acid carriers than in man. Taken together with the data
obtained in mammals, our results suggest that there may be a relationship between EFA activity and the distribution of the
EFA among the lipoprotein lipid fractions in vertebrates, irrespective of the EFA series. Administration of an (n−3) fatty
acid deficient diet for three months prior to trout spawning produced a significant increase in egg lipid content, primarily
as a result of the increase of the oil globule composed almost exclusively of triacylglycerols. This diet decreased the 22∶6
(n−3), as well as the (n−3) fatty acid contents of lipoproteins, lipovitellin, vitellogenin and the oil globule. In contrast,
the (n−3) fatty acid level was always higher in lipoproteins and lipovitellin than in the vitellogenin and the oil globule.
Moreover, the relative levels of 22∶6 (n−3) and total (n−3) fatty acids were quite similar in lipoproteins and lipovitellin
on the one hand, and in vitellogenin and the oil globule on the other. These findings suggest a direct relationship between
the two forms of plasma lipid transport and the two egg compartments. During ovogenesis, dietary lipids seemed to be diverted
from the adipose tissue and essentially deposited in the egg. 相似文献
32.
The nucleation, growth and coalescence of grain-boundary cavities is the primary damage mechanism observed during creep of structural ceramics. Furthermore, grain-boundary sliding (GBS) has been identified as the driving force process. Although the creep characteristics of structural ceramics have been extensively studied, very little is known about the details of GBS during creep and how GBS relates to cavitation kinetics. This paper presents the results of a study using a machine vision system to measure Mode II GBS displacements in a Lucalox Al2O3. Specifically, sliding displacements as large as 0.4 m were measured. The measured displacements indicate that some grain boundaries experienced shear strains and strain rates of 4200% and 2.3×10–2 s–1, respectively. The techniques utilized for these measurements are described in detail, and data gathered during a 2 1/2 h compressive creep test under a stress of 138 MPa at 1600 °C are presented and discussed. 相似文献
33.
Didier Bardon Dick Berry Carolyn Bjerke Dave Roberts 《International journal of human-computer interaction》2013,29(3-4):535-558
This article provides an introduction to the usage of software engineering approaches and tools for the design of user experience (UE). This approach was developed for three main reasons: (a) to provide UE design teams a rigorous, methodical, encompassing method that can be applied throughout the entire product development cycle; (b) to provide designers a way to work with abstract concepts to establish the conceptual design of the system before progressing to the realization of the design to the appropriate platform; and (c) to communicate the intended design to the implementation team in a manner that is concise, complete, and familiar. The approach is the application of Unified Modeling Language concepts to describe users and the UE design rather than the technical architecture. It is believed that designing the UE design separately from the technical architecture will help ensure teams deliver a usable and delightful UE. The methods in this article have been applied to a handful of real-world projects in the last year and a half. Thus far, the application of software engineering approaches and tools have been found to be very powerful aids that have enabled the creation of highly useful Web experiences as well as software applications. Our intent is to address the full gamut of issues involved in creating a total user experience (UE)-from discovery of users needs through high-level and low-level design, ensuring fidelity during development, and deployment, with a full assessment of how well the design meets users' needs. We believe that through a concerted use of such a rigorous approach we can greatly improve not only the UE of products we create, but also the experience of designing and developing them. We are not the only team taking this direction in UE design. It has become clear to many in our field that a more rigorous, thorough, and accurate approach to UE design is not only possible-it is necessary, for many of the same reasons that software engineers long ago embraced such practices. As we are evolving our approaches in other phases, this article focuses on the discovery and design phase activities. 相似文献
34.
The measurement of the flow through complex combined sewer overflow structures in the frame of automated monitoring remains difficult. In this paper, a methodology based on the use of computational fluid dynamics (CFD) modelling in order to improve the instrumentation of a downstream-controlled dual-overflow structure is presented. The dual-overflow structure is composed of two combined sewer overflows (CSOs) connected by a rectangular channel and controlled by a downstream gate located at the entry of the Meyzieu waste water treatment plant (close to Lyon, France). The analysis of the CFD results provides: (i) a better understanding of the interaction between the two CSOs--that means the hydraulic operation, the hydrodynamic behaviour, the backflow effect--and (ii) an ability to optimise the location of the water depth sensor. The measured water depth is used to assess the overflow rate by means of a numerical relationship. Uncertainties are also assessed. 相似文献
35.
J. F. Barbot P. Girault C. Blanchard I. A. Hümmelgen 《Journal of Materials Science》1995,30(13):3471-3474
Deep level transient spectroscopy (DLTS) has been used to study the traps associated with dislocations in n-type Hg0.3Cd0.7Te. Dislocations have been generated by ion implantation at high fluence. Two of the broadened lines (E1=E
c–0.22eV and E1=E
c–0.34eV), we have observed, show a logarithmic dependence with the filling pulse. They are characteristic of point defect clouds surrounding or generated by the dislocations. An unusual broadened line (E2=E
c–0.27eV) has also been observed, its amplitude decreases for filling pulses longer than 50 s. This can be explained by a configuration change of the defect leading to the appearance of a new DLTS line. In addition, an electron trap (EP4=E
c–0.22eV), which seems to behave like an isolated point defect, has also been found. 相似文献
36.
El Baz Didier Fakih Bilal Sanchez Nigenda Romeo Boyer Vincent 《The Journal of supercomputing》2022,78(3):3122-3151
The Journal of Supercomputing - The multiplication of computing cores in modern processor units permits revisiting the design of classical algorithms to improve computational performance in complex... 相似文献
37.
Jean-François Jerier Vincent Richefeu Didier Imbault Fréderic-Victor Donzé 《Computer Methods in Applied Mechanics and Engineering》2010,199(25-28):1668-1676
We introduce a new geometric method to generate sphere packings with restricted overlap values. Sample generation is an important, but time-consuming, step that precedes a calculation performed with the discrete element method (DEM). At present, there does not exist any software dedicated to DEM which would be similar to the mesh software that exists for finite element methods (FEM). A practical objective of the method is to build very large sphere packings (several hundreds of thousands) in a few minutes instead of several days as the current dynamic methods do. The developed algorithm uses a new geometric procedure to position very efficiently the polydisperse spheres in a tetrahedral mesh. The algorithm, implemented into YADE-OPEN DEM (open-source software), consists in filling tetrahedral meshes with spheres. In addition to the features of the tetrahedral mesh, the input parameters are the minimum and maximum radii (or their size ratio), and the magnitude of authorized overlaps. The filling procedure is stopped when a target solid fraction or number of spheres is reached. Based on this method, an efficient tool can be designed for DEMs used by researchers and engineers. The generated packings can be isotropic and the number of contacts per sphere is very high due to its geometric procedure. In this paper, different properties of the generated packings are characterized and examples from real industrial problems are presented to show how this method can be used. The current C++ version of this packing algorithm is part of YADE-OPEN DEM [20] available on the web (https://yade-dem.org). 相似文献
38.
39.
Michael Zock Olivier Ferret Didier Schwab 《International Journal of Speech Technology》2010,13(4):201-218
No doubt, words play a major role in language production, hence finding them is of vital importance, be it for writing or
for speaking (spontaneous discourse production, simultaneous translation). Words are stored in a dictionary, and the general
belief holds, the more entries the better. Yet, to be truly useful the resource should contain not only many entries and a
lot of information concerning each one of them, but also adequate navigational means to reveal the stored information. Information
access depends crucially on the organization of the data (words) and the access keys (meaning/form), two factors largely overlooked.
We will present here some ideas of how an existing electronic dictionary could be enhanced to support a speaker/writer to
find the word s/he is looking for. To this end we suggest to add to an existing electronic dictionary an index based on the
notion of association, i.e. words co-occurring in a well balanced corpus, the latter being supposed to represent the average
citizen’s knowledge of the world. Before describing our approach, we will briefly take a critical look at the work being done
by colleagues working on automatic, spontaneous or deliberate language production,—that is, computer-generated language, simulation of the mental lexicon, or WordNet (WN),—to see how adequate they are with regard to our goal. 相似文献
40.
The language MLF is a proposal for a new type system that supersedes both ML and System F, allows for efficient, predictable, and complete type inference for partially annotated terms. In this work, we revisit the definition of MLF, following a more progressive approach and focusing on the design-space and expressiveness. We introduce a Curry-style version iMLF of MLF and provide an interpretation of iMLF types as instantiation-closed sets of Dash System-F types, from which we derive the definition of type-instance in iMLF. We give equivalent syntactic definition of the type-instance, presented as a set of inference rules. We also show an encoding of iMLF into the closure of Curry-style System F by let-expansion. We derive the Church-style version eMLF by refining types of iMLF so as to distinguish between given and inferred polymorphism. We show an embedding of ML in eMLF and a straightforward encoding of System F into eMLF. 相似文献