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Search Results: 1 - 10 of 591924 matches for " Alejandro A Camacho-Dávila "
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Experimental and quantum chemical studies of a novel synthetic prenylated chalcone
José C Espinoza-Hicks, Alejandro A Camacho-Dávila, Norma R Flores-Holguín, Guadalupe V Nevárez-Moorillón, Daniel Glossman-Mitnik, Luz M Rodríguez-Valdez
Chemistry Central Journal , 2013, DOI: 10.1186/1752-153x-7-17
Abstract: A novel substituted chalcone has been synthetized. In order to identify the functional groups present in the new synthesized compound and confirm its chemical structure, experimental and theoretical 1H-NMR and 13C-NMR spectra were analyzed. The theoretical molecular structure and NMR spectra were calculated at both the Hartree-Fock and Density Functional (meta: TPSS; hybrid: B3LYP and PBE1PBE; hybrid meta GGA: M05-2X and M06-2X) levels of theory in combination with a 6-311++G(d,p) basis set. The structural parameters showed that the best method for geometry optimization was DFT:M06-2X/6-311++G(d,p), whereas the calculated bond angles and bond distances match experimental values of similar chalcone derivatives. The NMR calculations were carried out using the Gauge-Independent Atomic Orbital (GIAO) formalism in a DFT:M06-2X/6-311++G(d,p) optimized geometry.Considering all HF and DFT methods with GIAO calculations, TPSS and PBE1PBE were the most accurate methods used for calculation of 1H-NMR and 13C-NMR chemical shifts, which was almost similar to the B3LYP functional, followed in order by HF, M05-2X and M06-2X methods. All calculations were done using the Gaussian 09 software package. Theoretical calculations can be used to predict and confirm the structure of substituted chalcones with good correlation with the experimental data.Chalcones are ubiquitous substances found in a diversity of plants. They are precursors to other natural products, such as flavonoids, which have reported a wide range of biological activities such as antioxidant, antibacterial, antitumoral among others [1]. Due to the importance of these compounds, diverse studies on synthesis and biological activities of molecules containing the chalcone ring system, have been reported recently [2]. The prenyloxychalcones are important derivatives of chalcones, which contain a prenyl-type side chain with different length, including 2,2-dimethylallyl, geranyl or farnesyl chains; these compounds have shown i
Pyrene-Fullerene C60 Dyads as Light-Harvesting Antennas
Gerardo Zaragoza-Galán,Jesús Ortíz-Palacios,Bianca X. Valderrama,Alejandro A. Camacho-Dávila,David Chávez-Flores,Víctor H. Ramos-Sánchez,Ernesto Rivera
Molecules , 2014, DOI: 10.3390/molecules19010352
Abstract: A series of pyrene -fullerene C 60 dyads bearing pyrene units (PyFC 12, PyFPy, Py 2FC 12 and PyFN) were synthesized and characterized. Their optical properties were studied by absorption and fluorescence spectroscopies. Dyads were designed in this way because the pyrene moeities act as light-harvesting molecules and are able to produce “monomer” (PyFC 12) or excimer emission (PyFPy, Py 2FC 12 and PyFN). The fluorescence spectra of the dyads exhibited a significant decrease in the amount of pyrene monomer and excimer emission, without the appearance of a new emission band due to fullerene C 60. The pyrene fluorescence quenching was found to be almost quantitative, ranging between 96%–99% depending on the construct, which is an indication that energy transfer occurred from one of the excited pyrene species to the fullerene C 60.
Cambios morfométricos durante el beneficio tradicional de las vainas de vainilla (Vanilla planifolia; Orchidaceae) en México
Tapia-Ochoategui, A.P.;Camacho-Díaz, B.H.;Perea-Flores, M.J.;Ordó?ez-Ruíz, I.M.;Gutiérrez-López, G.F.;Dávila-Ortiz, G.;
Revista mexicana de ingeniería química , 2011,
Abstract: in this work, microstructural changes of the tissues of vanilla were evaluated during the curing, using an environmental scanning electron microscope (esem). the morphometric parameters: area (a), perimeter (p), shape factor (sf) and compactness (c) of each tissue (epicarp, mesocarp and vascular bundle) were quantified by digital image analysis (dia). results indicated that curing induces structural disruptions of the vanilla tissues which is more pronounced in the mesocarp. shape factor and compactness showed highest values in pods subjected to 10 cycles of sunning-sweating (10 ss) in which the highest concentration of vanillin and the lowest water looses were detected. it is possible to recommend a reduction of curing time from 20-25 ss cycles to 10.
Four Cases of X-Linked Hypophosphatemic Rickets, Clinical Description and Genetic Testing  [PDF]
David Vila-Pérez, Sílvia Marín-del-Barrio, Jordi Vila-Cots, Jose Antonio Camacho-Díaz, Marcos Morey, Lourdes Loidi
Open Journal of Genetics (OJGen) , 2014, DOI: 10.4236/ojgen.2014.41006
Abstract:

One of the major causes of congenital hypophosphatemic rickets is the X-linked hypophosphatemic rickets (XHR), due to a defect on PHEX gene. The XHR increases the renal elimination of phosphate, that condition leads a defective mineralization of bones and also affects the growth in children. Clinical diagnosis should be suspected in children with signs of rickets and hypophosphatemia with normal calcium levels. We describe clinical characteristics and genetic results of four patients diagnosed and treated in our Nephrology Section. All patients have a de novo XHR as none familiars are affected. Early diagnosis should be suspected before the bone deformities have been submitted and the growth would have been impaired.

Concentración de azadiractina, efectividad insecticida y fitotoxicidad de cuatro extractos de Azadirachta indica A. Juss
Esparza-Díaz, Gabriela;López-Collado, José;Villanueva-Jiménez, Juan A.;Osorio-Acosta, Francisco;Otero-Colina, Gabriel;Camacho-Díaz, Eloy;
Agrociencia , 2010,
Abstract: the preparation of effective neem-based bioinsecticides (azadirachta indica a. juss.) requires the extraction and concentration of its active ingredients, given that they are not found in large quantities in a natural form. simple cold press, methanolic cold press (methanolic), soxhlet-hexane (hexanic) and aqueous (aqueous) neem extracts were compared with respect to the concentration of azadirachtin (aza) and its insecticidal effectiveness against aphis gossypii glover, as well as possible toxic effects on ixora coccinea l. the experimental design was completely randomized. an analysis of variance was made with the data and the means were compared with the tukey test (p≤0.05). analyses of extracts by hplc showed significantly different concentrations (2478, 565, 422 and 150 ppm) of aza in the methanolic, hexanic, oily and aqueous extracts. the bioassay to determine the insecticidal effect and the phytotoxicity of the extracts consisted of exposing 10 nymphs of.4. gossypii to leaves of i.coccinea treated with each extract to doses of 0.01, 0.1 and 0.2 mg f aza in 5 cm2, and a control with water, with three replicates. mortality was measured at 24, 48 and 72 h. only the oily extract produced lesions in 35 % of the treated leaf area with moderate damage and level 5 phytotoxicity in i.coccinea. significant differences were found in the mortality of a. gossypii per type of extract, time and dose, as well as in the interactions dose time and dose type of extract. the extract with the highest insecticide potential was the methanolic (0.2 mg aza), with 100 % mortality at 48 and 72 h (p≤0.0001). the simultaneous application of methanol and cold press extracts more aza from the seed of a. indica, promoting a higher insecticidal activity.
Fractal morphology of Beta vulgaris L. cell suspension culture permeabilized with Triton X-100
M. Arenas-Ocampo , L. Alamilla-Beltrán , P. E. Vanegas-Espinoza , B. H. Camacho-Díaz , R. Campos-Mendiola , G. Gutiérrez-López , A. Jiménez-Aparicio
International Agrophysics , 2012, DOI: 10.2478/v10247-012-0001-2
Abstract: In this work, morphology of Beta vulgaris L. cells permeabilized with 0.7mM of Triton X-100 was evaluated using digital image processing and concepts of fractal dimension (perimeter- area relations). Important morphometric changes were found when the contact-time with chemical agent was increased. The size of cells decreased, the cells lost the roundness and their shape was more sinuous; this behaviour was a result of a probable shrinkage caused by the excess of exposure with the permeabilization agent. Morphology of B. vulgaris cells after permeabilization, exhibited a fractal nature since the slope of the ratio of the logarithm of the perimeter vs logarithm of the area was higher than unit. Fractal geometry of the cell morphology was affected as a result of the exposure to Triton X-100 . Those changes can be attributed to the loss of turgor and structure of the cell wall.
Cateterización de la vena subclavia en pacientes pediátricos menores de 10 kg de peso Subclavian vein catheterization in children with weight less than 10 kg
Franco Díaz R,Alejandro Donoso F,Jorge Camacho A,Pablo Cruces R
Revista chilena de pediatría , 2006,
Abstract: El acceso venoso central es requerido frecuentemente en las Unidades de Cuidados Intensivos Pediátricos, ya sea con fines de monitorización o terapéuticos. En nuestro medio, el acceso venoso subclavio está aún poco extendido en los pacientes pediátricos críticamente enfermos. Objetivo: Demostrar que la cateterización venosa central de la vena subclavia (VSC) en menores de 10 kg de peso es una alternativa exitosa y segura de efectuar por médicos staff de UCI. Dise o: Estudio prospectivo observacional, período 2003 a 2005 (34 meses). Pacientes: Todos los pacientes ingresados menores de 10 kilos de peso en quienes se instaló vía infraclavicular un acceso subclavio por técnica de Seldinger. Medición: Se registraron las características demográficas y antropométricas de los pacientes y sus condiciones clínicas relevantes. Se tabularon las variables técnicas del procedimiento (lugar de acceso, número de intentos) y las complicaciones asociadas. Se realizó análisis de subgrupos según peso (menor o igual a 5 kg o mayores a 5 kg). Resultados: Se efectuaron 73 canulaciones en 51 pacientes, 59% masculino, rango de edad de 8 días y 18 meses y de peso entre 2,3 y 9,6 kg (mediana 5 kg), 78% en ventilación mecánica, 62% se ubicaron en vena subclavia derecha. Para el grupo total se canuló exitosamente la VSC en 70/73 (96%, 64% al primer intento) y fue de 97% y 95% para los menores y mayores de 5 kg respectivamente. Ocurrieron 9 (12%) complicaciones, correspondiendo a 4 (5%) mayores (neumotórax). No hubo diferencia en los dos grupos analizados para éxito de canulación y complicaciones. Conclusiones: La instalación percutánea de la VSC es segura de emplear en ni os bajo 10 kg de peso, presentando un bajo riesgo de complicación. Debe ser considerada como una alternativa más de abordaje para el ni o críticamente enfermo. Central venous access are often required in Pediatric Intensive Care Units for hemodynamic monitorization and treatment. The subclavian vein catheterization is unfrequently used in critically ill children. Objective: To demonstrate that subclavian vein catheterization performed by pediatric staff is a safe and successful access in children with body weight less than 10 kg. Method: Prospective and observational study that lasts 34 months and includes children with body weight less than 10 kg. A subclavian central venous access was attempted by infraclavicular approach with Seldinger technique. The demographic and anthropometric characteristics of the patients and their relevant clinical conditions were registered. The technical variables of the procedure (in
Dynamical polaron ansatz: a theoretical tool for the ultra-strong coupling regime of circuit QED
Guillermo Díaz-Camacho,Alejandro Bermudez,Juan José García-Ripoll
Physics , 2015,
Abstract: In this work we develop a semi-analytical variational ansatz to study the properties of few photon excitations interacting with a collection of quantum emitters in regimes that go beyond the rotating wave approximation. This method can be used to approximate both the static and dynamical properties of a superconducting qubit in an open transmission line, including the spontaneous emission spectrum and the resonances in scattering experiments. The approximations are quantitatively accurate for rather strong couplings, as shown by a direct comparison to Matrix-Product-State numerical methods, and provide also a good qualitative description for stronger couplings well beyond the Markovian regime.
Cateterización de la vena subclavia en pacientes pediátricos menores de 10 kg de peso
Díaz R,Franco; Donoso F,Alejandro; Camacho A,Jorge; Cruces R,Pablo; León B,José;
Revista chilena de pediatría , 2006, DOI: 10.4067/S0370-41062006000500004
Abstract: central venous access are often required in pediatric intensive care units for hemodynamic monitorization and treatment. the subclavian vein catheterization is unfrequently used in critically ill children. objective: to demonstrate that subclavian vein catheterization performed by pediatric staff is a safe and successful access in children with body weight less than 10 kg. method: prospective and observational study that lasts 34 months and includes children with body weight less than 10 kg. a subclavian central venous access was attempted by infraclavicular approach with seldinger technique. the demographic and anthropometric characteristics of the patients and their relevant clinical conditions were registered. the technical variables of the procedure (insertion side, number of attempts) and related complications were listed. group analysis was made according to weight (< 5 kg or > 5 kg). results: 73 catheter insertions were performed in 51 patients; 59% male with age between 8 days and 18 months, weight between 2,3-9,6 kg (median 5 kg). 62% were placed in the right side. 78% cases required mechanical ventilation. 70 out of 73 attempts (96%) were successful (64% first attempt), 97% belonging to the group with weight < 5 kg and 95% to the ones with body weight > 5 kg. 9 (12%) complications occurred. there were no differences between both groups in terms of success and procedure related complications. conclusions: percutaneous subclavian vein catheterization is safe in children with body weight less than 10 kg and it presents low risk of complications. this procedure must be considered as an alternative in critically ill children
Los clusters industriales del noreste de México (1993-2003): Perspectivas de desarrollo en el marco de una mayor integración económica con Texas
Dávila Flores, Alejandro;
Región y sociedad , 2008,
Abstract: using the methodology developed by feser and bergman (2000), the industrial clusters of northeast mexico are identified. the economic performance of clusters between 1993 and 2003 is analyzed using regional economic analysis techniques. finally, the opportunities of cluster development are explored within the framework of a greater commercial integration with the state of texas.
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