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Plasma fatty acid (FA) composition is known to be an indicator of dietary fat quality, but the associations of other dietary factors with plasma FA composition remain unknown in children. We investigated the cross-sectional associations of food consumption with the proportions of FA and estimated desaturase activities in plasma cholesteryl esters (CE) and phospholipids (PL) among children. The subjects were a population sample of 423 children aged 6–8 years examined at baseline of The Physical Activity and Nutrition in Children (PANIC) Study. We assessed food consumption by food records and plasma FA composition by gas chromatography. We used linear regression models adjusted for age, sex, physical activity and total energy intake to analyze the associations. A higher consumption of vegetable oil-based margarine (fat 60–80 %) was associated with a higher proportion of linoleic and α-linolenic acids in plasma CE and PL. A higher consumption of high-fiber grain products was related to a lower proportion of oleic acid in CE and PL. The consumption of candy was directly associated with the proportion of palmitoleic and oleic acid in plasma CE. The consumption of vegetable oil-based margarine was inversely associated with estimated stearoyl-CoA-desaturase activity in plasma CE and PL and the consumption of candy was directly related to it in plasma CE. The results of our study suggest that plasma FA composition is not only a biomarker for dietary fat quality but also reflects the consumption of high-fiber grain products and foods high in sugar among children.  相似文献   
2.
Extended AMR-WB for high-quality audio on mobile devices   总被引:2,自引:0,他引:2  
This article presents the architecture, performance, and application scenarios of the AMR-WB+ (extended AMR-WB) audio codec, which provides high quality at exceptionally low rates, and consistent quality over all audio types. This codec was recently selected by 3GPP and DVB to support low-bit-rate audio and audiovisual applications on mobile networks.  相似文献   
3.
Dark fermentative biohydrogen production in a thermophilic, xylose-fed (50 mM) fluidised bed reactor (FBR) was evaluated in the temperature range 55–70 °C with 5-degree increments and compared with a mesophilic FBR operated constantly at 37 °C. A significantly higher (p = 0.05) H2 yield was obtained in the thermophilic FBR, which stabilised at about 1.2 mol H2 mol?1 xylose (36% of the theoretical maximum) at 55 and 70 °C, and at 0.8 mol H2 mol?1 xylose at 60 and 65 °C, compared to the mesophilic FBR (0.5 mol H2 mol?1 xylose). High-throughput sequencing of the reverse-transcribed 16S rRNA, done for the first time on biohydrogen producing reactors, indicated that Thermoanaerobacterium was the prevalent active microorganism in the thermophilic FBR, regardless of the operating temperature. The active microbial community in the mesophilic FBR was mainly composed of Clostridium and Ruminiclostridium at 37 °C. Thermophilic dark fermentation was shown to be suitable for treatment of high temperature, xylose-containing wastewaters, as it resulted in a higher energy output compared to the mesophilic counterpart.  相似文献   
4.
The influence of different inoculum pretreatments (pH and temperature shocks) on mesophilic (37 °C) and thermophilic (55 °C) dark fermentative H2 production from xylose (50 mM) and, for the first time, on the composition of the active microbial community was evaluated. At 37 °C, an acidic shock (pH 3, 24 h) resulted in the highest yield of 0.8 mol H2 mol?1 xylose. The H2 and butyrate yield correlated with the relative abundance of Clostridiaceae in the mesophilic active microbial community, whereas Lactobacillaceae were the most abundant non-hydrogenic competitors according to RNA-based analysis. At 55 °C, Clostridium and Thermoanaerobacterium were linked to H2 production, but only an alkaline shock (pH 10, 24 h) repressed lactate production, resulting in the highest yield of 1.2 mol H2 mol?1 xylose. This study showed that pretreatments differentially affect the structure and productivity of the active mesophilic and thermophilic microbial community developed from an inoculum.  相似文献   
5.
The composition, biodegradability, abundance, availability and cost determine the amenability of carbonaceous substrate for fermentative hydrogen and methane production systems. The aim of the present work was to determine suitability of lignocellulosic material, reed canary grass (RCG) (Phalaris arundinacea L.), for hydrogen and methane production at 35 °C by utilizing solid RCG and acid hydrolyzed soluble RCG. Synthetic cellulose was used as control substrate. Acid hydrolysis released 61.7 mg g−1 (dw) and 115 mg g−1 (dw) of reducing sugars from synthetic cellulose and chopped RCG, respectively. More hydrogen was produced from acid hydrolyzed RCG than from solid RCG, the highest yield being 1.25 mmol H2 per g (dw) RCG. Methane production from solid RCG resulted in the highest yield of 8.26 mmol CH4 per g (dw) RCG. In summary hydrogen and methane was produced from RCG, and acid hydrolysis was required for hydrogen, but not for methane production.  相似文献   
6.
Wideband speech is the major differentiation and attraction of third-generation network services in both the circuit and packet switched domain. Increased audio bandwidth introduces a significant leap in perceived quality of service compared to currently utilized narrowband telephony in second-generation mobile communications and the PSTN. The adaptive multirate wideband (AMR-WB) speech codec is the service enabler for improved user experience. It is an established 3GPP and ITU-T wideband speech codec standard and represents the state-of-the-art in speech quality as well as robustness in error prone radio channels. It is also the first codec algorithm standardized for wideband speech for mobile communications.  相似文献   
7.
The conditions for an enhanced mutual miscibility of water and Canola oil, with the aid of one or two surface active components, were investigated at 25 C. First, the ability of short chain alcohols to increase the mutual solubility was charted. Such systems frequently are denoted detergentless microemulsions. Second, normal microemulsion systems were formed by using surface active monoglycerides of foodstuff grade. Third, the synergism was monitored when both the surfactant and the cosurfactant (the alcohols) were mixed either with water or oil. Finally, the combined effect was determined when all four components were mixed together into a microemulsion system. It is shown that the extension of the ternary solution phase is dependent primarily on the surfactant used. Some improvement of the mutual solubility of water and oil, however, also was produced by the alcohols. The solubilization capacity of water in the quaternary systems is easily understood when the solution phase is compared with the microemulsion phases of the ternary systems included. Although no dramatic composition dependency was found, an enhanced solubility of water was observed for the oil rich microemulsions of roughly equal weight fractions of the surfactant components. Presented in part at the 8th Scandinavian Symposium on Surface Chemistry, Lund, Sweden, 1984.  相似文献   
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