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Electron Paramagnetic Resonance of Gd3＋ in Cs 2Na Y0.75 H o0.25CI6

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材料科学与工程（中英文B版） 2011年第3期1卷 352-357页

作者： Josefina Maldonado Jorge Barreto Jose luis Boldu Hector del Castillo eduardo Mufioz Picone Instituto de Fisica Universidad Nacional Autonoma de Mexico Circuito de la Investigacion Cientifica Ciudad Universitaria D.F. 04510 Mexico

The Application of the Generalized Finite Difference Method (GFDM) for Modelling Geophysical Test

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Journal of Geoscience and Environment Protection 2019年第4期7卷 1-17页

作者： Angel Muelas eduardo Salete Juan José Benito Francisco Urena luis Gavete Miguel Urena UNED ETS Ingenieros IndustrialesC/Juan del RosalMadridSpain UCLM IMACICiudad RealSpain UPM ETSIMMadridSpain

The possibility of using a nodal method allowing irregular distribution of nodes in a natural way is one of the main advantages of the generalized finite difference method (GFDM) with regard to the classical finite difference method. Moreover, this feature has made it one of the most-promising meshless methods because it also allows us to reduce the time-consuming task of mesh generation and the numerical solution of integrals. This characteristic allows us to shape geological features easily whilst maintaining accuracy in the results, which can be a source of great interest when dealing with this kind of problems. Two widespread geophysical investigation methods in civil engineering are the cross-hole method and the seismic refraction method. This paper shows the use of the GFDM to model the aforementioned geophysical investigation tests showing precision in the obtained results when comparing them with experimental data.

关键词： Meshless Methods Generalized Finite Difference Method Geophysics

Contamination of Water for Domestic Use and Human Consumption by Heavy Metals Derived from Mining Activity in Parral, Chihuahua, Mexico

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Journal of Environmental Science and Engineering(A) 2012年第3期1卷 286-294页

作者： luis Miguel Rodriguez Ever Torres luis Saenz Maria del Carmen Avitia Guillermo Rodriguez eduardo Herrera Carmen Julia Navarro Guillermo Gonzalez luis Lozoya Damaris Acosta Technological Institute of Parral Parral Chihuahua 33850 Mexico Research Center for Advanced Materials （CIMA V） Chihuahua 31109 Mexico

Research was done with the objective of evaluating the quality of water supplied to the potable water system in Hidalgo Del Parral, which comes from two main supply sources： wells from ＂Valle del Verano＂, which provide water to the east side of the city, and the Water Treatment Plant, which receives water from different mines and supplies the west side of the city. When this plant is overcome on its capacity of treatment, a part of the water from the mines is fed directly to the northwest part of the city. The metals lead （Pb）, chromium （Cr）, cadmium （Cd）, zinc （Zn）, and arsenic （As） were analyzed by atomic absorption （AA） technique, based on the United States Environmental Protection Agency （EPA） Method 7000B （Revision 2, February 2007）. The digestion process was done according to the guidelines established in Method NMX-AA-051-SCFI-2001, Analysis of Water-Determination of Metals by Atomic Absorption, developed by the National Standardization Technical Committee for Environmental Protection （Mexico）. The samples were collected from the following points： 13 wells and 2 re-pumping stations of ＂Valle del Verano＂, the inlet and outlet of the Water Treatment Plant, and domestic faucets. The east side of the city, supplied by the wells of ＂Valle del Verano＂, is metal-pollution free. The water that comes from the mines contains high concentrations of As, Zn, Cd and Pb, with levels that can get to 0.12, 32.6, 0.26 and 3.5 mg/L, respectively. This water pollution generated by mining can be concluded from the high levels found in the domestic samples in which, for several points, the concentrations exceed the parameters set by the current guideline. According to the results, it is vital to set a plan of remediation for the water that comes from the mines, because there is a great risk for health in the consumotion of this water.

关键词： Heavy metals mining water contamination.

Balloon-assisted enteroscopy for suspected Meckel's diverticulum and indefinite diagnostic imaging workup

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World Journal of Gastrointestinal Endoscopy 2016年第18期8卷 679-683页

作者： Guilherme Francisco gomes eduardo Aimore Bonin Rafael William Noda Leandro Totti Cavazzola Thiago Ferreira Bartholomei Endoscopy Unit Nossa Senhora das Gracas Hospital Curitiba 81830 Brazil Universidade Federal do Rio Grande do Sul Porto Alegre 91740 Brazil

Meckel’s diverticulum (MD) is estimated to affect 1%-2% of the general population, and it represents a clinically silent finding of a congenital anomaly in up to 85% of the cases. In adults, MD may cause symptoms, such as overt occult lower gastrointestinal bleeding. The diagnostic imaging workup includes computed tomography scan, magnetic resonance imaging enterography, technetium 99m scintigraphy (99mTc) using either labeled red blood cells or pertechnetate (known as the Meckel’s scan) and angiography. The preoperative detection rate of MD in adults is low, and many patients ultimately undergo exploratory laparoscopy. More recently, however, endoscopic identification of MD has been possible with the use of balloon-assisted enteroscopy via direct luminal access, which also provides visualization of the diverticular ostium. The aim of this study was to review the diagnosis by double-balloon enteroscopy of 4 adults with symptomatic MD but who had negative diagnostic imaging workups. These cases indicate that balloon-assisted enteroscopy is a valuable diagnostic method and should be considered in adult patients who have suspected MD and indefinite findings on diagnostic imaging workup, including negative Meckel’s scan.

关键词： Double-balloon enteroscopy Meckel&rsquo s diverticulum Diagnosis

Power Tensor Theory and Continuous Wavelet Transform

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American Journal of Computational Mathematics 2012年第2期2卷 130-135页

作者： eduardo Antonio Cano-Plata Armando Jaime Ustariz-Farfán luis Fernando Díaz-Cadavid Departmentof Electrical Electronic and Computer Engineering National University of Colombia Manizales Colombia

A model for the definition of electrical Power is presented, which retrieves the concepts of homomorphism from the geometrical tensor approximation at the wavelet approach. Their definition here is nevertheless different in that it considers both tensor algebra and wavelet operators, solving thus most of the problems usually associated with the numerical methods.

关键词： Wavelets Tensor Electrical Power Power Electronic Power Quality

Induced Dipoles in Electromagnetic Media in Motion

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Journal of Electromagnetic Analysis and Applications 2018年第11期10卷 185-192页

作者： José-Antonio-eduardo Roa-Neri José-luis Jiménez-Ramírez Ignacio Campos-Flores área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México México D. F. México

We present a non-relativistic approach to the equivalent polarization Peq=(1/c2)v×Meq, that appears in a magnetized medium in motion. We apply an analogous method to that used by Panofsky and Phillips to calculate the symmetric effect, the equivalent magnetization that appears in a polarized dielectric in motion, Meq=P×v,?This method is based on a particular expression of Maxwell’s equations and the application of the convective derivative. These authors argue, however, that the equivalent polarization can be obtained only with a relativistic approach. We show that with the same method, but with a different and equivalent expression of Maxwell’s equations, this effect can also be calculated. In this way both effects can be considered relativistic effects to first order in v/c.

关键词： Moving Media Polarized Dielectric Macroscopic Maxwell Equations Induction of Magnetic Dipoles

Production and Partial Characterization of an Extracellular Phytase Produced by Muscodor sp. under Submerged Fermentation

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Advances in Microbiology 2016年第1期6卷 23-32页

作者： Natálie Martins Alves luis Henrique Souza Guimarães Roberta Hilsdorf Piccoli Patrícia gomes Cardoso Department of Biology Sector of Microbiology Federal University of Lavras Lavras Brazil Department of Biology University of Sao Paulo Ribeirao Preto Brazil Department of Food Science Federal University of Lavras Lavras Brazil

In most of the raw materials of plant origin used in animal feed, a portion of the phosphorus is stored as phytic acid or phytate. Phytate is the main storage form of phosphorus in vegetables but is not readily assimilated into food at low concentrations of the enzyme phytase. In addition to making phosphorous unavailable, phytate binds divalent cations such as calcium, copper, magnesium, iron, manganese and zinc, preventing the absorption of these nutrients in the gut of the animal. Phytase promotes the hydrolysis of the phytate phosphorus-releasing molecule, thereby increasing its bioavailability in feed. Phytase is distributed in plant and animal tissues and it is synthesized by some species of bacteria and fungi. The addition of this enzyme in the diet of animals is essential to promote greater uptake of phosphorus and also contributes to a decrease in the levels of phosphorus excreted by animals, thus reducing the pollution caused by excess phosphorus in the environment. This work aimed to select a fungus that stands out in the production of phytase among 100 isolates from Brazilian caves belonging to the genera Aspergillus, Penicillium and Cladosporium and 13 endophytic fungi of the aerial part of the coffee plant. For selection, the fungi were cultured in medium containing phytic acid as a sole source of phosphorus. After seven days at 25 °C, we evaluated growth and enzyme production by the presence of the phytic acid halo degradation (Enzymatic Index-EI) surrounding the colonies. Forty-seven species produced phytase, and the fungi Penicillium minioluteum (CF279) and Muscodor sp. (UBSX) showed higher degradation halos, 2.41 and 4.46, respectively. Considering the Muscodor sp. as the main source of phytase, high enzymatic levels were obtained when the fungus was grown under submerged fermentation with initial pH of 5.0 using wheat bran as additional carbon source for 144 h, at 125 rpm and 30 °C. Additionally, the enzyme was stable at pH 5.0 and 40 °C, and inhi

关键词： Endophytic Fungus Muscodor sp. Phosphorus Phytase Phytic Acid

Catalytic Performance of La0.6Ca0.4Fe1-xNixO3Perovskites in DME Oxidation

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Modern Research in Catalysis 2015年第4期4卷 97-106页

作者： Gina Pecchi Ruddy Morales Daniela Salinas eduardo J. Delgado José luis García Fierro Facultad Ciencias Químicas Universidad de Concepción Concepción Chile Instituo Catálisisy Petroleoquímica CSIC Cantoblanco Madrid Spain

Substituted La0.6Ca0.4Fe1-xNixO3 (0.0 ≤ x ≤ 1.0) perovskite-type oxides prepared by the amorphous citrate method have been investigated as catalysts in the dimethyl ether (DME) oxidation reaction. The samples with an x ≤ 0.3 composition show an orthorhombic structure, while the intermediate compositions with 0.5 ≤ x ≤ 0.9 show a less crystalline orthorhombic perovskite structure with segregated phases that increase upon increasing the Ni content. The progressive substitution of Fe3+ by Ni2+ in La0.6Ca0.4FeO3 entails the progressive formation of oxygen vacancies and Fe4+ species for Ni substitution degrees of x ≤ 0.5. For larger degrees of substitution with x > 0.7, segregated phases and a progressive loss of the perovskite structure are detected. The highest catalytic performance for the total combustion of DME is obtained from equimolar substitution in the B-site position (Fe0.5Ni0.5), in which a large extent of Fe4+ species and oxygen vacancies are present.

关键词： DME Perovskites Oxidation Iron Nickel

Stress cardiomyopathy: clinical features and outcomes

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Health 2010年第4期2卷 300-305页

作者： Lilian Hamity Franco Ramello Leandro Marani Alejandro Moyano eduardo Moreyra luis E. Alday 不详

Objectives: To establish the prevalence, clinical features, and outcomes of the recently recog- nized stress cardiomyopathy whose physiopathology is still not completely clarified. Material and methods: The prevalence and clinical findings of stress cardiomyopathy were assessed in a group of 378 patients undergoing cinecoronariography for acute coronary syndromes dur- ing a 7-year period. The inclusion criteria were severe chest pain, ischemic electrocardiogra- phic changes, reversible left ventricular dys- hypokinesia, and normal coronary arteries. Eight patients, 7 female (2.1% of all patients and 5.0% of the women), with a mean age of 65.3 ± 8.5 years fulfilled the requirements. Results: The precipitating factor was severe stress in all of them. Cardiac enzymes were slightly raised. There was apical left ventricular dyskinesia in 6 patients, midventricular in another, and diffuse hypokinesia in the remaining. One patient showed moderate mitral regurgitation. The response to con- ventional treatment and patient outcomes were favorable in all cases with prompt reversal of the left ventricular dyskinesia as assessed by echocardiography. There were 4 recurrences, 2 requiring readmission to hospital, despite continuous treatment with combined alfa and beta adrenergic blockers and calcium antagonists. Conclusions: In our hospital, stress cardiomyo- pathy had a prevalence of 2.1% in all patients with acute coronary syndromes and 5.1% in women and should be considered in their differential diagnosis, especially in middle aged female patients with a history of severe previous stress. There was a favorable outcome but recurrences may occur despite uninterrupted me- dical treatment following discharge.

关键词： Stress Cardiomyopathy Takotsubo Syndrome Myocardial Ischemia Cardiomyopathy