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991.
Flore Dagorn Justine Dumay Gaëtane Wielgosz-Collin Vony Rabesaotra Michèle Viau Claude Monniot Jean-François Biard Gilles Barnathan 《Lipids》2010,45(3):253-261
Two tunicates, Eudistoma sp. and Leptoclinides uniorbis, collected from the tropical waters off Djibouti were investigated for lipids and phospholipid (PL) fatty acids. PL accounted
for 38.2% of the total lipids in Eudistoma sp. and for 30.2% in L. uniorbis. PL classes were quantified by normal-phase high-performance liquid chromatography using an evaporative light-scattering detector
and revealed essential differences. Eudistoma sp. contained mainly phosphatidylcholine (PC, 70.3% of total PL) and lysophosphatidylcholine (LPC, 11.9%) and was devoid
of phosphatidylserine (PS), whereas the major PL of L. uniorbis was PS (59.1%) followed by PC (22.5%) and LPC (8.8%). Gas chromatography–mass spectrometry analyses of fatty acid (FA) derivatives
revealed 38 FA in Eudistoma sp., and 35 FA in L. uniorbis, ranged from C12 to C24 chain lengths. Polyunsaturated FA accounted for 25.9% in Eudistoma sp. and for 32.3% in L. uniorbis. Interestingly, L. uniorbis contained a high percentage (16.7%) of the 20:5n-3 acid (8.9% in Eudistoma sp.) and the 18:4n-3 acid (4.1%). Significant levels of the 20:4n-6 acid were observed in both organisms (7.8 and 6.0% respectively).
Eudistoma sp. contained the rare 20:3n-7 acid (2.3%) only recorded to date in hydrothermal vent animals. The cyclopropane dihydrosterculic
acid was identified in both tunicates (0.7 and 0.5% respectively). These latter FA, together with some unusual branched saturated
and monounsaturated FA, revealed the occurrence of associated bacteria in the tunicates. Another noticeable feature was a
series of eight C16 to C18 aldehyde dimethylacetals revealing the presence of plasmalogens at 5.0% in Eudistoma sp. and 14.2% in L. uniorbis. The results of this study were compared with those previously published for other tunicates regarding mainly PL content
and FA composition. 相似文献
992.
Symmetric porous membranes were prepared from concentrated poly(ether-imide) (PEI) solutions using vapor-induced phase separation (VIPS) coupled with a drying pretreatment. Moderately concentrated solutions of PEI in N-methylpyrrolidinone (NMP) (14–16 wt%) were first cast on glass plates and the solvent was then allowed to evaporate under a dry air flow up to the desired concentration (16–38 wt%) before forming the membrane structure by VIPS. The polymer concentration profiles (confocal Raman microscopy) and model predictions were in good agreement to show that the evaporation stage did not induce a polymer gradient concentration with PEI/NMP systems. These results were confirmed by examination of the final membrane morphology (SEM). 相似文献
993.
0引言法国皮拉德EGCI股份公司(PILLARD EGCI)成立于1919年,是专业从事锅炉、回转窑及分解炉燃烧设备的专业公司。在世界范围内,皮拉德公司提供的水泥及其它矿物处理行业的回转窑及分解炉燃 相似文献
994.
Maham Yasmeen Syed Asif Ansar Amir Azam Khan Thierry Joyeux Jean Claude Labbe 《Journal of Materials Engineering and Performance》2001,10(5):542-547
Commercial zirconia was milled and sedimented to separate finer and coarser particles. Then additives such as CaO and Y2O3 were added in proportions of 7 and 13 mol.% each. Wet mixing of these powders was done in the ball mill. These mixtures were
then compacted through uniaxial compaction using 150 MPa of pressure to make pellets of 8 mm diameter and 3 mm height approximately.
The compacts were sintered at 1700 °C under argon atmosphere during 1 h. Densification calculations revealed densities of
more than 80% in all samples. Scanning electron microscopy (SEM) showed that closed porosity was present. X-ray diffraction
(XRD) results confirmed the presence of cubic phase with quantities higher in samples of finer powder and 13 mol.% additive. 相似文献
995.
Claude Thibeault 《Journal of Electronic Testing》2000,16(4):339-353
This paper presents a diagnostic method based on differential IDDQprobabilistic signatures, inspired by telecommunications systems. The method and its unique features are described. Then, results from an IC monitor containing controllable faults show the capability of the method to diagnose actual activated faults, despite a strong experimental current standard variation. These results validate previous simulation procedures, which are applied to quantify effects not covered by the monitor experiment, that is, the effect of the load of a bridged node and the effect of the bridge resistance value. These experimental and simulation results reveal the robustness of the proposed diagnosis method, that has identified and located every single fault considered so far. 相似文献
996.
一、中国的缺水问题在中国的很多地区,可用水量的日益减少是当前最大的社会、经济和政治问题。以人均可用量2500m3的标准相比较,中国大陆的淡水供应只达到2000m3,属于世界 相似文献
997.
Thomas Gaudron Claude Peters Elodie Boland André Steinmetz Gilbert Moris 《European Food Research and Technology》2009,229(2):295-305
With the ever increasing number of genetically modified plants authorized worldwide, including in the European Union, high
throughput detection methods need to be developed. In this paper, a quadruplex-real-time-PCR method is described which allows
rapid and simultaneous screening of food for the presence of target DNA sequences from the cauliflower mosaic virus 35S promoter,
the NOS terminator from Agrobacterium tumefaciens, the soya reference lectin gene and the maize reference alcool dehydrogenase gene (adh). Three of the four primers and probe
combinations have already been published elsewhere, whereas primers and probe for NOS terminator-PCR were developed in-house.
Validation data show sensitivities down to five copies for 35S promoter and NOS terminator PCR, even when target sequences
of the competing PCRs are in large excess. Thorough adjustment of primer and probe concentrations allowed high individual
PCR efficiencies with negligible physical cross-talk between the four detection channels. This method provides a basis for
a rapid screening of food for the most frequently used regulatory elements present in GM crops authorized for food in the
European Union. In addition it provides information about the presence of species which are possibly genetically modified. 相似文献
998.
999.
Ziqi Guan Jing Bai Jianglong Gu Xinzeng Liang Die Liu Xinjun Jiang Runkai Huang Yudong Zhang Claude Esling Xiang Zhao Liang Zuo 《材料科学技术学报》2021,68(9):103-111
In this work,the B2 partial disordered structure of the austenitic parent phase,martensitic transformation,elastic and magnetic properties of the Ni8 Mn4+xTi4-x(x=0,1 and 2) Heusler alloys have been systematically investigated by the first-principles calculations.The preferential atomic occupation of B2 structure is one Ti atom exchange with the nearest neighboring Mn atom from the view of lowest energy principle.This disordered exchange sites(Mn-Ti) and the excess Mn atoms occupying the Ti sites(MnTi)could reduce the nearest Mn-Mn distance,resulting in the anti ferromagnetic state in the austenitic and martensitic phases of the alloys.The total magnetic moment of the alloy decreases with the increasing Mn content;it is ascribed to the antiferromagnetic magnetic moments of the excess Mn atoms.When x=0,the alloy does not undergo martensitic transformation since the austenite has absolute phase stability.The martensitic transformation will occur during cooling process for x=1 or 2,owing to the energy difference between the austenite and the martensite could provide the driving force for the phase transformation.The elastic properties of the cubic austenitic phase for the Ni2 MnTi alloy is calculated,and the results reveal the reason why Ni-Mn-Ti alloy has excellent mechanical properties.The origin of martensitic transformation and magnetic properties was discussed based on the electronic density of states. 相似文献
1000.
Kowalczewska M Fenollar F Villard C Azza S Roux M Raoult D 《Proteomics. Clinical applications》2008,2(4):504-516
Whipple's disease (WD) is a chronic multisystemic infection, caused by the bacterium Tropheryma whipplei. The main clinical presentations are classic WD (CWD) with histologic lesions in the gastrointestinal tract, endocarditis, and isolated neurologic infection. The current strategy for diagnosis remains invasive.The present study aimed to select the protein candidates for serological diagnosis of WD. The first step was to identify candidate proteins by an immunoproteomic approach combining 2‐DE using a total extract of a T. whipplei, immunoblotting, and MS. The second step was to validate the discovered biomarkers using a recombinant protein‐based ELISA. Serum samples from 18 patients with WD and from 54 control individuals were tested. A sugar ABC transporter, TWT328 (sensitivity (Se) 61%, specificity (Sp) 87%, positive predictive value (PPV) 61%, negative predictive value (NPV) 87%, and positive likelihood ratio (PLR) 4.69) was the best marker for development of serodiagnosis for CWD. We also obtained a reproducible immunoreactive protein pattern for patients with isolated neurological infection due to T. whipplei (Se 100%, Sp 93%, PPV 55.5%, NPV 100%, and PLR 13.51) as an encouraging step towards noninvasive diagnosis of this particular manifestation. Nine recombinant candidates have been successfully screened with serum samples. Results from these ELISA assays skewed with those obtained with immunoblots. 相似文献