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排序方式: 共有2392条查询结果,搜索用时 0 毫秒
911.
Flavonoid metabolite 3‐(3‐hydroxyphenyl)propionic acid formed by human microflora decreases arterial blood pressure in rats 下载免费PDF全文
912.
L‐cysteine supplementation upregulates glutathione (GSH) and vitamin D binding protein (VDBP) in hepatocytes cultured in high glucose and in vivo in liver,and increases blood levels of GSH,VDBP, and 25‐hydroxy‐vitamin D in Zucker diabetic fatty rats 下载免费PDF全文
913.
Quellec G Lamard M Josselin PM Cazuguel G Cochener B Roux C 《IEEE transactions on medical imaging》2008,27(9):1230-1241
In this paper, we propose an automatic method to detect microaneurysms in retina photographs. Microaneurysms are the most frequent and usually the first lesions to appear as a consequence of diabetic retinopathy. So, their detection is necessary for both screening the pathology and follow up (progression measurement). Automating this task, which is currently performed manually, would bring more objectivity and reproducibility. We propose to detect them by locally matching a lesion template in subbands of wavelet transformed images. To improve the method performance, we have searched for the best adapted wavelet within the lifting scheme framework. The optimization process is based on a genetic algorithm followed by Powell's direction set descent. Results are evaluated on 120 retinal images analyzed by an expert and the optimal wavelet is compared to different conventional mother wavelets. These images are of three different modalities: there are color photographs, green filtered photographs, and angiographs. Depending on the imaging modality, microaneurysms were detected with a sensitivity of respectively 89.62%, 90.24%, and 93.74% and a positive predictive value of respectively 89.50%, 89.75%, and 91.67%, which is better than previously published methods. 相似文献
914.
Baptiste Trajin Marie Chabert Jrmi Regnier Jean Faucher 《Mechanical Systems and Signal Processing》2009,23(8):2648-2657
This paper deals with mechanical fault diagnosis in three-phase induction machines from stator current measurements. According to machine models, mechanical faults lead to amplitude and/or phase modulations of the measured stator current with possibly time varying carrier frequency. The modulation diagnosis requires a univocal definition of the instantaneous phase and amplitude. This is performed by associating a complex signal to the real measured one. For a convenient separate modulation diagnosis, the complex signal instantaneous phase and amplitude are expected to carry, respectively, information about the phase and amplitude modulations. The complex signal is classically obtained through the Hilbert transform. Under Bedrosian conditions, the so-called analytic signal allows a separate modulation diagnosis. However, mechanical faults may also produce fast modulations violating the Bedrosian conditions. This study proposes an alternative complex signal representation which takes advantage of the three stator current measurements available in a three-phase machine. From two stator current measurements, the Concordia transform builds a complex vector, the so-called space vector, which unconditionally allows separate modulation diagnosis. This paper applies and compares the Hilbert and Concordia transforms, theoretically and in case of simulated and experimental signals with various modulation frequency ranges. 相似文献
915.
Marie Groenbaek Ulla Kidmose Erik Tybirk Hanne Lakkenborg Kristensen 《Journal of food science》2019,84(7):1888-1899
The chemical and sensory quality of field‐grown vegetables may be influenced by cultivar choice and agronomic factors but knowledge is lacking on the new rapeseed vegetables. White‐ and yellow‐flowering rapeseed cultivars were tested in two seasonally different field studies in Denmark at three different growing stages by early sowing the first year and late sowing the second year. Content of glucosinolates (GLSs) was analyzed, and the sensory quality of baby leaf samples was evaluated. The GLS content differed among cultivars across years in all growing stages, with biennial cultivars having the highest GLS content. In the second year, a higher content of all identified GLSs was found at two growing stages except for neoglucobrassicin and gluconasturtiin, compared to the first year. On the contrary, higher contents of all identified GLSs were found at a third stage in the first year except for progoitrin and 4‐methoxy glucobrassicin. Sensory evaluation of bitterness revealed differences among cultivars, higher intensities of bitterness in biennial cultivars, and a relationship between bitterness and content of bitter‐tasting and total GLSs. The effect of repeated harvesting on GLS content differed between the years and no general pattern was seen, except that the composition of individual GLSs was comparable for the biennial cultivars. We conclude that growing season and life cycle had a stronger influence on GLS content than stage at harvest. The link between bitter‐tasting GLSs and bitterness revealed that life cycle and seasonal effects affected the sensory profile of baby leaf rapeseed thereby making a healthier product due to high content of health‐beneficial GLSs. 相似文献
916.
Effect of muscle type,aging technique,and aging time on oxidative stability and antioxidant capacity of beef packed in high‐oxygen atmosphere 下载免费PDF全文
917.
Foko Kouam Edith Marius Kaktcham Pierre Marie Wang Rui Yan Zhu Taicheng Yin Li 《Food Biotechnology》2018,32(1):15-34
The present study aimed to evaluate selected probiotic properties of Lactobacilli isolated from the water of submerged cassava fermentation. Following Lactobacilli isolation, isolates were screened for their antimicrobial activity. Acid and bile tolerances, bile salt hydrolase (Bsh) activity spectrum were assessed. Among the 113 isolates obtained, 16 showed a broad antimicrobial activity spectrum against the indicator microorganisms. From these 16, 12 were found acid and bile resistant. They hydrolyzed glycoconjugated or tauroconjugated bile salts. From the four bile Bsh genes screened, only Bsh-Lp1 was found in five isolates. They identified as Lactobacillus paraplantarum, Lactobacillus paracasei, Lactobacillus brevis, and Lactobacillus plantarum. Based on the principal component analysis, L. paracasei 62L, L. plantarum 85L and 86L were selected as the most promising strains. These results suggest that water from submerged cassava fermentation can be a source of Lactobacilli with high probiotic potential. 相似文献
918.
919.
Alternative uses of waste for energy production become increasingly interesting when considered from two perspectives, that of waste management and the energy system perspective. This paper presents the results of an enquiry into the use of waste in a future energy system. The analysis was performed using the energy system analysis model, Balmorel. The study is focused on Germany and the Nordic countries and demonstrates the optimization of both investments and production within the energy systems. The results present cost optimization excluding taxation concerning the use of waste for energy production in Denmark in a 2025 scenario with 48% renewable energy. Investments in a range of waste conversion technologies are facilitated, including waste incineration, co-combustion with coal, anaerobic digestion, and gasification. The most economically feasible solutions are found to be incineration of mixed waste, anaerobic digestion of organic waste, and gasification of part of the potential RDF (refuse derived fuel) for CHP (combined heat and power) production, while the remaining part is co-combusted with coal. Co-combustion mainly takes place in new coal-fired power plants, allowing investments to increase in comparison with a situation where only investments in waste incineration are allowed. 相似文献
920.
Identification of Signaling Pathways Targeted by the Food Contaminant FB1: Transcriptome and Kinome Analysis of Samples from Pig Liver and Intestine 下载免费PDF全文