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91.
Background: High protein (HP) diets have been proposed to reduce body weight in humans. The diets are known to alter energy metabolism, which can affect the quality of [18F]FDG PET heart images. In this preclinical study, we therefore explore the impact of a prolonged HP diet on myocardial [18F]FDG uptake. Methods: C57BL/6J (Black six (Bl6)) and apolipoprotein E-deficient (apoE−/−) mice were fed chow, a HP diet, or a low protein (LP) diet for 12 weeks. At baseline and after treatment, the animals were injected with 33.0 MBq of [18F]FDG and a 30 min PET/CT scan was made. Myocardial volume and [18F]FDG uptake were quantified using PET and the % of body fat was calculated from CT. Results: Myocardial [18F]FDG uptake was similar for all diets at the follow-up scan but an increase between baseline and follow-up scans was noticed in the LP groups. Myocardial volume was significantly smaller in the C57BL HP group compared to the other Bl6 groups. Body weight increased less in the two HP groups compared to the chow and LP groups. Body fat percentage was significantly higher in the LP groups. This effect was stronger in C57BL mice (28.7%) compared to apoE−/− mice (15.1%). Conclusions: Myocardial uptake of [18F]FDG in mice is not affected by increased protein intake but [18F]FDG uptake increases when the amount of protein is lowered. A lower body weight and percentage of body fat were noticed when applying a HP diet.  相似文献   
92.
In this paper a new operation principle of an air-conditioning system for hydrogen driven cars is proposed and experimental results of a laboratory prototype are presented. The system is able to utilize the potential energy of the compressed hydrogen gas as main driving energy to generate a cooling effect usable for e.g. air-conditioning. Therefore, it is able to partially reuse the compression energy originally spent in order to increase the energy density of hydrogen but is so far wasted onboard. The underlying principle of the process is based on a chemical reaction of a metal hydride (Ti0.99Zr0.01V0.43Fe0.09Cr0.05Mn1.5) with hydrogen at different pressures and corresponding equilibrium temperatures. The laboratory prototype consists of two alternating capillary tube bundle reactors (together around 5 kg and 1.5 l) and is able to generate a quasi-continuous cooling effect at 13 °C in the order of 900 W.  相似文献   
93.
Genetically modified maize is grown extensively in the world today. MaisGard (Monsanto, Yieldgard in the USA) is a genetically modified maize harbouring the Mon810 transformation event. European Community legislation requires that genetically modified organisms (GMOs) be approved before they are placed on the market. Labelling is required when more than 1% of any ingredient of a food originates from a GMO. There is consequently a need for specific, quantitative methods for detection of genetically modified foods. We have determined the DNA sequence of the 5'-flanking region of the Mon810 insert using ligation mediated PCR. A primer probe set overlapping the junction was designed and used in a quantitative, event-specific Taqman 5'-nuclease assay. Mon810 DNA was quantified relative to endogenous maize zein gene DNA. The results were expressed as the percentage of genetically modified Mon810 maize DNA relative to the total content of maize DNA.  相似文献   
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Oil palm shell (OPS) nanoparticles were utilized as filler in fibers reinforced polyester hybrid composites. The OPS nanoparticles were successfully produced from the raw OPS using high-energy ball milling process. Fundamental properties including morphology, crystalline size, and particle size of the OPS nanoparticles were determined. Tri-layer natural fiber reinforcement (kenaf–coconut–kenaf fiber mat) polyester hybrid composites were prepared by hand lay-up techniques. The influences of the OPS nanoparticles loading in the natural fibers reinforced polyester hybrid composites were determined by analyzing physical, mechanical, morphological, and thermal properties of the composites. Results showed that the incorporation of the OPS nanoparticles into the hybrid composites enhanced the composite properties. Further, the natural fibers reinforced polyester hybrid composite had the highest physical, mechanical, morphological, and thermal characteristics at 3 wt.% OPS nanoparticles loading.  相似文献   
97.
杭州RAFFLES城     
杭州Raffles城发展坐落于浙江省省会杭州市的钱塘江边,是嘉德置地继新加坡、上海、北京、成都和巴林之后的第六栋,将零售店、办公楼、住户和酒店设施融于一体,成为新城区的文化地标。  相似文献   
98.
Supporting the early phases of design requires, among others, support for the specification and use of multiple and evolving representations, and for the exchange of information between these representations. We consider a complex adaptive system as a model for the development of design representations, and present a semi-constructive algebraic formalism for design representations, termed sorts, as a candidate for supporting this approach. We analyze sorts with respect to the requirements of a complex adaptive system and compare it to other representational formalisms that consider a constructive approach to representations. We demonstrate the advantages of sorts in various examples, illustrate its use to support the specification of design queries and the recognition of emergent information, and consider sorts in relationship to integrated product models.  相似文献   
99.
Experimental data of Ca-induced activated sludge flocculation under different conditions of temperature and dissolved oxygen are investigated in order to model the influence of changing physical and chemical factors. However, current kernel structures for collision frequency and efficiency are unable to describe activated sludge flocculation data. Therefore, an earlier developed methodology based on an inverse problem is applied, yielding empirical models, to find out how flocculation is affected by these different environmental conditions. This contribution shows the useful application of inverse problems to improve the understanding of complex aggregation mechanisms.  相似文献   
100.
Attentional bias to negative information has been proposed to be a cognitive vulnerability factor for the development of depression. In 2 experiments, the authors examined mood-congruent attentional bias in dysphoria. In both experiments, dysphoric and nondysphoric participants performed an attentional task with negative, positive, and neutral word cues preceding a target. Targets appeared either at the same or at the opposite location of the cue. Overall, results indicate that dysphoric participants show maintained attention for negative words at longer stimulus presentations, which is probably caused by impaired attentional disengagement from negative words. Furthermore, nondysphoric participants maintain their attention more strongly to positive words. These results are discussed in relation to recent developments in the pathogenesis and treatment of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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