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JETP Letters - Extraordinary multiparticle effects in quantizing magnetic fields that are manifested in strongly interacting two-dimensional electron systems in MgZnO/ZnO heterostructures have been... 相似文献
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Karen Beatriz Méndez-Rodríguez Nicté Figueroa-Vega César Arturo Ilizaliturri-Hernandez Mónica Cardona-Alvarado Jaime Antonio Borjas-García Carlos Kornhauser Juan Manuel Malacara Rogelio Flores-Ramírez Francisco Javier Pérez-Vázquez 《Biomedical chromatography : BMC》2020,34(12):e4956
Metabolomics is a potential tool for the discovery of new biomarkers in the early diagnosis of diseases. An ultra-fast gas chromatography system equipped to an electronic nose detector (FGC eNose) was used to identify the metabolomic profile of Volatile Organic Compounds (VOCs) in type 2 diabetes (T2D) urine from Mexican population. A cross-sectional, comparative, and clinical study with translational approach was performed. We recruited twenty T2D patients and twenty-one healthy subjects. Urine samples were taken and analyzed by FGC eNose. Eighty-eight compounds were identified through Kovats's indexes. A natural variation of 30% between the metabolites, expressed by study groups, was observed in Principal Component 1 and 2 with a significant difference (p < 0.001). The model, performed through a Canonical Analysis of Principal coordinated (CAP), allowed a correct classification of 84.6% between healthy and T2D patients, with a 15.4% error. The metabolites 2-propenal, 2-propanol, butane- 2,3-dione and 2-methylpropanal, were increased in patients with T2D, and they were strongly correlated with discrimination between clinically healthy people and T2D patients. This study identified metabolites in urine through FGC eNose that can be used as biomarkers in the identification of T2D patients. However, more studies are needed for its implementation in clinical practice. 相似文献
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Hendrik Van Maldeghem 《Journal of Geometry》1997,58(1-2):192-202
We characterize in a geometrical way those Suzuki-Tits ovoids which are defined over a perfect fieidK (or equivalently living inside a self polar symplectic quadrangle). We simplify our axioms in the particular cases that (1) the associated Suzuki group has exactly two orbits in the set of lines ofPG(3,K), and (2) the ovoid is finite.Senior Research Associate at the Belgian National Fund for Scientific Research 相似文献
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Photobleaching was studied during recording of confocal scanning laser microscopy. Studies on fluorescent gels of FITC-labeled
dextran were used to evaluate differential bleaching along thez-axis. Differential bleaching along the z-axis was observed and it was seen that this was related to the numerical aperture
of the objective in use. This points to the conclusion that photon energy flux density is an important parameter in photobleaching.
To check if photon energy flux density heterogeneity is affected by local variation in the refractive index of the sample,
photobleaching rates were calculated for different fluorescent objects (sections of seeds, animal cells stained with nuclear
stains, immunocytochemistry preparations) and a pronounced similarity was found between photobleaching rates and DIC images. 相似文献