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991.
Dr. Morgan Le Naour Dr. Veronique Leclerc Dr. Amaury Farce Dr. Daniel‐Henri Caignard Dr. Nathalie Hennuyer Prof. Bart Staels Dr. Valérie Audinot‐Bouchez Dr. Jean‐Albert Boutin Dr. Michel Lonchampt Dr. Catherine Dacquet Prof. Alain Ktorza Prof. Pascal Berthelot Dr. Nicolas Lebegue 《ChemMedChem》2012,7(12):2179-2193
Compounds that simultaneously activate peroxisome proliferator‐activated receptor (PPAR) subtypes α and γ have the potential to effectively treat dyslipidemia and type 2 diabetes (T2D) in a single pharmaceutically active molecule. The frequently observed side effects of selective PPARγ agonists, such as edema and weight gain, were expected to be overcome by using additive PPARα activity, leading to dual PPARα/γ agonists with balanced activity for both subtypes. Herein we report the discovery, synthesis, and optimization of a new series of α‐ethoxyphenylpropionic acid bearing 5‐ or 6‐substituted indoles. The incorporation of oxime ethers on the carbonyl portion of the benzoyl group can bring the PPARα/γ potency ratio equal to or slightly greater than one, as is the case for compounds 20 c and 21 a . Compound 20 c shows high efficacy in an ob/ob mouse model of T2D and dyslipidemia, similar to that of rosiglitazone and tesaglitazar, but with a significant increase in body weight gain. In contrast, compound 21 a , less potent as a dual PPARα/γ activator than 20 c , showed an interesting pharmacological profile, as it elicits a decrease in body weight relative to reference compounds. 相似文献
992.
Jardin J Mollé D Piot M Lortal S Gagnaire V 《International journal of food microbiology》2012,155(1-2):19-28
Due to increasingly available bacterial genomes in databases, proteomic tools have recently been used to screen proteins expressed by micro-organisms in food in order to better understand their metabolism in situ. While the main objective is the systematic identification of proteins, the next step will be to bridge the gap between identification and quantification of these proteins. For that purpose, a new mass spectrometry-based approach was applied, using isobaric tagging reagent for quantitative proteomic analysis (iTRAQ), which are amine specific and yield labelled peptides identical in mass. Experimental Swiss-type cheeses were manufactured from microfiltered milk using Streptococcus thermophilus ITG ST20 and Lactobacillus helveticus ITG LH1 as lactic acid starters. At three ripening times (7, 20 and 69 days), cheese aqueous phases were extracted and enriched in bacterial proteins by fractionation. Each sample, standardised in protein amount prior to proteomic analyses, was: i) analysed by 2D-electrophoresis for qualitative analysis and ii) submitted to trypsinolysis, and labelled with specific iTRAQ tag, one per ripening time. The three labelled samples were mixed together and analysed by nano-LC coupled on-line with ESI-QTOF mass spectrometer. Thirty proteins, both from bacterial or bovine origin, were identified and efficiently quantified. The free bacterial proteins detected were enzymes from the central carbon metabolism as well as stress proteins. Depending on the protein considered, the quantity of these proteins in the cheese aqueous extract increased from 2.5 to 20 fold in concentration from day 7 to day 69 of ripening. 相似文献
993.
Benjamin Dewals Sébastien Erpicum Pierre Archambeau Michel Pirotton 《Water and Environment Journal》2012,26(4):504-510
This work involves the experimental investigation of flow patterns, preferential regions of deposition and trapping efficiency in rectangular shallow reservoirs. The main flow patterns that can be encountered in rectangular shallow reservoirs are described: symmetrical flows without any reattachment point (S0), asymmetrical flows with one reattachment point (A1) and asymmetrical flows with two reattachment points (A2). The influence of geometrical and hydraulic parameters on reattachment lengths is intensively investigated. A shape parameter is introduced to classify symmetrical and asymmetrical flows. For each flow pattern, the preferential regions of deposition are studied. To conclude, a number of practical recommendations are given. Reservoirs with a shape parameter lower than 6.2 limit sediment deposition. Reservoirs with a shape parameter greater than 6.8 are favourable for sediment deposition. Finally, perspectives for maximizing and minimizing deposition are given, respectively by exploiting the great trapping potential of the flow pattern A1 and the poor trapping potential of the flow pattern S0. 相似文献
994.
Fatty acid profile and sensory characteristics of table eggs from laying hens fed hempseed and hempseed oil 总被引:1,自引:0,他引:1
Goldberg EM Gakhar N Ryland D Aliani M Gibson RA House JD 《Journal of food science》2012,77(4):S153-S160
Hempseed (HS) is rich in omega-3 polyunsaturated fatty acids, with approximately 17% of total fatty acids as alpha-linolenic acid. As such, HS and its oil may be used in hen diet formulations to produce eggs enriched in essential fatty acids. Because omega-3 eggs have the potential for unpleasant aromas and flavors, the current study was designed to assess the fatty acid profile and sensory attributes of eggs procured from hens consuming diets containing hempseed oil (HO) or HS. A total of 48 individually caged White Bovan hens received 1 of 6 diets containing 4%, 8%, 12% HO, 10%, 20% HS or 0% hemp (w/w) for 12 wk. Total omega-3 polyunsaturated fatty acid content was highest in the 12% HO group (15.3 mg/g of yolk) compared to the control (2.4 mg/g of yolk). Trained panellists (n= 8) found no significant differences (P≥ 0.05) in aroma or flavor between cooked eggs from different dietary treatments, with the exception of sweet flavor. The 4% HO group yielded the least sweet eggs compared to the 20% HS group, which was highest. For yolk color, L*, a*, and b* values (Mean ± SEM) for control eggs were 61.2 ± 0.10, 1.1 ± 0.05, and 43.0 ± 0.22, respectively. Addition of hemp led to significant (P < 0.001) reductions in L*, and significant increases in a* and b*, with the largest changes observed in the 20% HS treatment (L*= 58.7 ± 0.10; a*= 5.8 ± 0.05; b*= 60.5 ± 0.22). The results show that hemp use in hen diets leads to increased omega-3 polyunsaturated fatty acid content and color intensity of egg yolks, but does not have adverse effects on the sensory profiles of the cooked eggs. PRACTICAL APPLICATION: This study provides evidence that HS and hempseed oil (HO) can safely be utilized as feed ingredients for laying hens to produce table eggs that are enriched in essential fatty acids. Additionally, the eggs procured from these hens had similar aroma and flavor compared to eggs from hens not fed any hemp. The greater the dietary hemp inclusion, the more pigmented the resulting yolks became in terms of darkness, redness, and yellowness. 相似文献
995.
996.
Marlène Pérignon Jérôme Lecomte Michel Pina Anne Renault Camille Simonneau-Deve Pierre Villeneuve 《Journal of the American Oil Chemists' Society》2012,89(1):89-96
The nutritional profile and rheological behaviors of lipids is both due to fatty acid composition and regiodistribution on
external and internal positions of triacylglycerol. Actual methods for regiodistribution analysis having some restrictions,
there is still a need for investigating a safe, simple and environmentally friendly method for the sn-2 position analysis that could especially be used for the analysis of fats containing medium and short chain fatty acids.
The objective of this study was to evaluate the 1,3-selectivity and typoselectivity of Rhizopus oryzae lipase in the presence of short/medium chain fatty acids in partial hydrolysis conditions used for regiodistribution analysis.
Structured triacylglycerols containing eight-carbon-chain length fatty acids in the sn
-2 position were chemically synthesized using DCC/DMAP coupling agent and purification steps by flash-chromatography. The final
product showed very high purity and was used as the substrate for 1,3-selectivity evaluation. Typoselectivity was assessed
by investigating partial hydrolysis of equimolar blends of homogeneous TAG. This study confirmed the 1,3-selectivity of Rhizopus oryzae lipase in the hydrolysis conditions used, and revealed that this lipase was less influenced by fatty acids chain length than
pancreatic lipase. Considering this, Rhizopus oryzae lipase appeared to be a good candidate for regiodistribution analysis of fats containing medium and short chain fatty acids. 相似文献
997.
Michael B. Jakubinek Michel B. Johnson Mary Anne White Chaminda Jayasinghe Ge Li Wondong Cho Mark J. Schulz Vesselin Shanov 《Carbon》2012,50(1):244-248
The electrical resistivity of CNT yarns of diameters 10–34 μm, spun from multi-walled carbon nanotube arrays, have been determined from 2 to 300 K in magnetic fields up to 9 T. The magnetoresistance is large and negative at low temperatures. The thermal conductivity also has been determined, by parallel thermal conductance, from 5 to 300 K. The room-temperature thermal conductivity of the 10 μm yarn is (60 ± 20) W m?1 K?1, the highest measured result for a CNT yarn to date. The thermal and electrical conductivities both decrease with increasing yarn diameter, which is attributed to structural differences that vary with the yarn diameter. 相似文献
998.
Jean-Yves Tigli Stéphane Lavirotte Ga?tan Rey Vincent Hourdin Nicolas Ferry Christophe Vergoni Michel Riveill 《电信纪事》2012,67(7-8):313-327
Ubiquitous computing applications or widespread robots interactions execute in unforeseen environments and need to adapt to changeful available services, user needs, and variations of the environment. Context-awareness ability addresses such a need, enabling, through adaptation rules, applications to react to the perceived dynamic variations. Responses to adaptation have to be quick enough to maximize the time during which the application is coherent with its environment. Adaptation rules, associating variations of the environment to application reactions, are usually established at design time. However, in unforeseen and partially anticipated environments, we claim that adaptation rules have to be dynamically extensible to match previously unexpected variations. Our approach enables rule composition and ensures a deterministic result. We propose to use parameter adaptation to quickly respond to environmental variations and dynamic compositional adaptation to provide extensibility to the parameter adaptation. To foster even lower response times, we internalize context-awareness processing and decision into the application. 相似文献
999.
Donglin Wang Michel Fattouche Fadhel Ghannouchi 《Circuits, Systems, and Signal Processing》2012,31(3):1215-1227
In this paper, orthogonal frequency division multiplexing (OFDM) for time-based range estimation (TBRE) in a separable multipath
channel is investigated and analyzed with respect to its accuracy. First, the Cramer–Rao lower bound (CRLB) in a separable
multipath channel is theoretically derived, and indicates a similar expression to that for a single path channel. The CRLB
for non-data-bearing (NDB) OFDM transmission is compared to that for pseudo-noise (PN) transmission, demonstrating a large
performance gap in favor of the NDB OFDM. Furthermore, the maximum likelihood estimator (MLE) for TBRE in a separable multipath
channel is theoretically derived, also demonstrating a similar expression to that in a single path channel, except that several
peaks instead of one peak are expected in a separable multipath channel corresponding to all arrival paths. The MLE for TBRE
is then compared to the commonly used MLE for channel estimation, showing an equal performance in terms of mean square error
when using an NDB OFDM transmission. Simulation results demonstrate a good agreement with our proposed theory. 相似文献
1000.
Kameswaran?VengattaramaneEmail author Jonathan?Borremans Michiel?Steyaert Jan?Craninckx 《Analog Integrated Circuits and Signal Processing》2012,70(3):311-322
A digital resolution enhancement technique for time-to-digital converters (TDC) is proposed. This involves a simultaneous
multi-channel measurement of a time interval with low complexity TDC of varying low resolutions. The coarse outputs of each
converter are digitally post-processed to obtain an output whose precision is much better than that of the individual converters.
Three post-processing algorithms are proposed and their limitations in presence of converter non-idealities are analyzed.
A prototype system with 8 channels is implemented in 90 nm CMOS. 40MS/s output of each channel is algorithmically combined
to obtain over 2.2–3X measured improvement in the resolution in 4/6/8 channel modes, validating the system principle. The
chip occupies 0.3 mm2 and draws up to a maximum of 4 mA from a 1.2 V supply. 相似文献