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101.
102.
B Eisenmann P Nicolini A Charpentier JG Kretz JC Thiranos H Petit F Lévy 《Canadian Metallurgical Quarterly》1994,120(12):96-99
Atheroma lesions are often found in multiple localizations. In addition, operative mortality for aneurysms of the non-ruptured sub-renal aorta is mainly related to coronary risk. In an attempt to reduce coronary risk, coronarography was performed in all patients (n = 297) from January 1989. Operation for the aneurysm was performed in 192 patients (reasons for not operating were small size of the aneurysm, other contraindication). There were 5 deaths, all related to coronary artery disease. Coronary bypass was performed in 42 patients either before (n = 38) or at the same time (n = 4) as the operation for the aneurysm of the aorta. There were no operative deaths. These results clearly demonstrate the importance of search and treatment of associated coronary lesions in all patients with an aneurysm of the subrenal abdominal aorta. Coronary lesions should be treated whenever morphology allows. 相似文献
103.
Tornambé G Cornu A Pradel P Kondjoyan N Carnat AP Petit M Martin B 《Journal of dairy science》2006,89(6):2309-2319
Changes of terpene content in milk from cows grazing natural diversified upland pasture were examined in this observational trial. A homogeneous plot divided into 2 subplots was used from May 31 to July 1, 2003 (first growth) and again from October 1 to October 7, 2003 (vegetative regrowth). Each subplot was grazed by 6 dairy cows in 2 ways: strip grazing (SG), with new allocations of pasture strips at 2-d intervals, and paddock grazing (PG). The PG subplot was divided into 3 paddocks and the cows were moved to a new paddock on June 13 and June 24, 2003. Milk from the 6 cows was collected twice a week, pooled, and used for terpene analyses by dynamic headspace gas chromatography-mass spectrometry system. Twenty mono- and 23 sesquiterpenes desorbing from the milk fat were separated. The most abundant monoterpenes were β-pinene, α-pinene, γ-terpinene, limonene, α-tujene, terpinolene, and α-phellandrene. The most abundant sesquiterpenes were β-caryophyllene, α-copaene, β-cedrene, transmuurola-4-(14)-5-diene, β-bisabolene, and δ-cadinene. Both mono- and sesquiterpenes in SG milk increased across time with an 8-fold increase in total terpenes in milk from the beginning to the end of June. In parallel, dicotyledons, including the main terpene-rich plants, increased from 17 to 31% of total biomass of the vegetation and the development of Dactylis glomerata progressed from boot to ripening stage. The terpenes in PG milk were equivalent to those in SG milk for the first paddock at the beginning of June and remained constant or doubled for the sum of mono- and sesquiterpenes, respectively. The lower variability of the PG milk terpene content could be related to the opportunity that PG cows had to choose ingested herbage, whereas the SG cows had limited choice within the smaller allocated pasture strips. Milk from cows grazing regrowth pastures in October contained low levels of terpenes, and values were similar for PG and SG milks. Change in the sum of monoterpenes is representative of changes for most monoterpenes (except for limonene) and, conversely, the change in the sum of sesquiterpenes mainly reflected changes in β-caryophyllene and α-copaene. In addition to effects of botanical composition of pasture, it appears that terpene content in milk may vary according to factors linked to grazing management that need more intensive study. Nevertheless, current results raise questions about the precision of terpenes as feed tracers. 相似文献
104.
105.
K. Edem NTsoukpoe Hui Liu Nolwenn Le Pierrs Lingai Luo 《Renewable & Sustainable Energy Reviews》2009,13(9):2385-2396
In the past decade, long-term sorption and thermochemical heat storage has generated lot of interest. This paper presents the state of the art in this field of research, materials used in these systems and technological difficulties that researchers are set against. An emphasis is put on recent demonstrative projects including absorption and adsorption for long-term solar energy storage. It emerges that considerable breakthrough have been made. Even though there is no mature long-term sorption or thermochemical energy storage yet, primarily due to the high cost of materials, the suitability of this technology to long-term storage remains its main power of attracting. 相似文献
106.
A. Meinertzhagen D. Zander C. Petit M. Jourdain D. Gogenheim 《Microelectronics Reliability》2000,40(4-5)
The stress induced leakage current (SILC) in Si/SiO2 structures with thin gate oxides has a steady-state component which increases drastically when the oxide thickness decreases. It is generally agreed that the SILC is due to electron tunnelling trough stress-induced traps. However, it was observed that the SILC, created by Fowler–Nordheim injection, decays continuously when, after stress, the samples are positively or negatively biased at a low voltage. The decay is irreversible as long as the gate oxide is not biased at a high voltage. The present article adds complementary observations. It shows, first that the above phenomenon is observed in 3.5 nm thick oxides, secondly, that this phenomenon is stable as long as the temperature stays below 200°C, and thirdly, that during the SILC decay, the interface state density does not diminish. 相似文献
107.
Naoual Anoune Moustapha Nouiri Christian Arnaud Serge Petit Pierre Lanteri 《Journal of surfactants and detergents》2000,3(3):381-386
A series of new cationic surfactants was prepared by condensation of lactic acid with N,N-dimethyl propylamine, followed successively by acetylation with acid chloride or ester and by quaternization with dimethylsulfate.
Each surfactant and its precursors' structural assignments were based on infrared spectra and 1H and 13C nuclear magnetic resonance spectra. Critical micelle concentrations, contact angles, kinetics of drop spreading, and foam
capacities were determined. 相似文献
108.
Pierre Melchior Mathieu Pellet Julien Petit Jean-Marie Cabelguen Alain Oustaloup 《Signal, Image and Video Processing》2012,6(3):421-428
Muscle models are useful in bio-inspired robotic, because they allow to reproduce accurately natural motion. When they are used for robotic issue, they need to be compact and embeddable. The non-integer model order has the advantage to ensure a parametrical parsimony that permits to implant it easily on an embedded system. Thus, a fractional multi-model of muscle was identified and presented in later paper. This model is able to predict the response of a motor unit to an electrical stimulation, considering isometric contractions (that is to say, muscle length is constant). There are three different physiological types of motor unit (FR, FF, and S). The aim of this work is to study muscle length impact on the multi-model and the limitations of the linear multi-model. Previous paper was published using FR type motor unit. In this paper, the results of the study using S type motor unit are presented. 相似文献
109.
Mónica Serrano Julio Sahuquillo Salvador Petit Houcine Hassan José Duato 《The Journal of supercomputing》2012,59(3):1533-1551
Cluster computers represent a cost-effective alternative solution to supercomputers. In these systems, it is common to constrain the memory address space of a given processor to the local motherboard. Constraining the system in this way is much cheaper than using a full-fledged shared memory implementation among motherboards. However, memory usage among motherboards can be unfairly balanced. 相似文献
110.