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1.
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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José A. Anquela Teresa Cortés Miguel Gómez-Lozano Mercedes Siles-Molina 《Acta Mathematica Hungarica》2004,103(3):177-196
We investigate the basic properties of the different socles that can be considered in not necessarily semiprime associative
systems. Among other things, we show that the socle defined as the sum of minimal (or minimal and trivial) inner ideals is
always an ideal. When trivial inner ideals are included, this inner socle contains the socles defined in terms of minimal
left or right ideals.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
Jaime E. Muñoz Rivera Maria Grazia Naso 《Journal of Mathematical Analysis and Applications》2007,326(1):691-707
We study the asymptotic behavior of the solutions of a class of linear dissipative integral differential equations. We show in the abstract setting a necessary and sufficient condition to get an exponential decay of the solution. In the case of the lack of exponential decay, we find the polynomial rate of decay of the solution. Some examples are given. 相似文献
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Jaime Pfretzschner Pedro Cobo Francisco Simón María Cuesta Alejandro Fernández 《Applied Acoustics》2006,67(1):62-73
Microperforated panels (MPPs) coupled to a rigid wall have been proposed recently as an alternative to porous absorbers in situations having concerns with bacterial contamination and small particles discharge, like food, pharmaceutical and microelectronic industries. There exists also an increasing interest for MPP absorbers in the transportation industry and civil engineering. In general, an optimally designed MPP with good broadband absorption requires many submillimetric holes distributed over a panel of also submillimetric thickness. Such thin plates or foils become so fragile that they need to be protected from mechanical damage. In this paper, an alternative strategy is investigated which allows the design of MPPs with panels of millimetric thickness while maintaining their acoustic performance. These absorbers, named microperforated insertion units (MIUs), avoid the structural problems of the classical MPPs. An assessment of the sound absorption properties of these structures is presented. Comparisons between calculations and measurements are also made under two experimental conditions: plane waves at normal incidence (impedance tube) and free field (anechoic room). 相似文献
8.
Huseyin Bekir Yildiz Jaime Castillo Dmitrii A. Guschin Levent Toppare Wolfgang Schuhmann 《Mikrochimica acta》2007,159(1-2):27-34
An amperometric biosensor for the detection of phenolic compounds was developed based on the immobilization of tyrosinase
within an Os-complex functionalized electrodeposition polymer. Integration of tyrosinase within the redox polymer assures
efficient catechol recycling between the enzyme and the polymer bound redox sites. The non-manual immobilization procedure
improves the reproducibility of fabrication process, greatly reduces the desorption of the enzyme from the immobilization
layer, and, most importantly prevents fast inactivation of the enzyme by its substrate due to fast redox cycling.
A two-layer sensor architecture was developed involving ascorbic acid oxidase entrapped within an electrodeposition polymer
in a second layer on top of the redox polymer/tyrosinase layer. Using this sensor architecture it was possible to eliminate
the current interference arising from direct ascorbate oxidation up to a concentration of 630 μM ascorbic acid. The effects
of the polymer thickness, the enzyme/polymer ratio, and the applied potential were evaluated with respect to optimal sensor
properties. The sensitivity of the optimized sensors for catechol was 6.1 nA μM−1 with a detection limit of 10 nM, and for phenol 0.15 nA μM−1 with a detection limit of 100 nM. 相似文献
9.
In this work we show that the energy associated to the linear three-dimensional magneto-elastic system decays polynomially to zero as time goes to infinity, provided the initial data is smooth enough. 相似文献
10.
Jaime Wisniak 《The Chemical Educator》2000,5(5):263-268
Amedeo Avogadro was a multifaceted and prolific scientist active in many areas of physics and chemistry, but most of his results did not make a scientific impact. His hypothesis, equal volumes = equal number of molecules remained in obscurity until Cannizaro rekindled it by making it a stepping-stone in the development of the atomic theory. 相似文献