Certificación de Buenas Prácticas Clínicas: necesidad de preparar los sitios clínicos y los servicios involucrados en ensayos clínicos para alcanzar esta condición

Certify compliance with Good Clinical Practice of one or more clinical sites and services that perform clinical trials (or both) should be the aspiration of health institutions linked to these investigations. This letter provides an approach to the certification process of Good Clinical Ptactice from the 52nd Regulation issued in 2008 by the Drug Regulatory Agency of Cuba, the Center for State Control of the Quality of Medicines, Equipment and Medical Devices, which establishes the requirements for clinical sites. The role of the National Clinical Trials Coordinating Center is specified in the diagnosis of compliance with the requirements of the "Manual of Methods for the preparation of clinical sites with a view to their certification in Good Clinical Practice" and an assessment is offered Provincial Clinical Trials Group of Villa Clara on the preparation of University Provincial Hospital " health institution with the greatest potential in the territory to face this process.Certificar el cumplimiento de las Buenas Prácticas Clínicas de uno o más sitios y de servicios clínicos que realizan ensayos clínicos (o ambos) debe ser la aspiración de las instituciones de salud vinculadas a estas investigaciones. La presente misiva ofrece un acercamiento al proceso de certificación de Buenas Prácticas Clínicas a partir de la Regulación número 52 emitida en el año 2008 por la Agencia Reguladora de Medicamentos de Cuba y el Centro para el Control Estatal de la Calidad de los Medicamentos, Equipos y Dispositivos Médicos que establece los requisitos que deben cumplir los sitios clínicos. Se especifica el papel que desempeña el Centro Nacional Coordinador de Ensayos Clínicos en el diagnóstico del cumplimiento de los requisitos establecidos en el “Manual de procedimientos para la preparación de los sitios clínicos con vistas a su certificación en Buenas Prácticas Clínicas” y se ofrece una valoración del Grupo Provincial de Ensayos Clínicos de la Provincia de Villa Clara sobre la preparación del Hospital Provincial Universitario “Arnaldo Milián Castro”, institución de salud con mayor potencial en el territorio para enfrentar este proceso

Localized state and charge transfer in nitrogen-doped graphene

Nitrogen-doped epitaxial graphene grown on SiC(000?1) was prepared by exposing the surface to an atomic nitrogen flux. Using Scanning Tunneling Microscopy (STM) and Spectroscopy (STS), supported by Density Functional Theory (DFT) calculations, the simple substitution of carbon by nitrogen atoms has been identified as the most common doping configuration. High-resolution images reveal a reduction of local charge density on top of the nitrogen atoms, indicating a charge transfer to the neighboring carbon atoms. For the first time, local STS spectra clearly evidenced the energy levels associated with the chemical doping by nitrogen, localized in the conduction band. Various other nitrogen-related defects have been observed. The bias dependence of their topographic signatures demonstrates the presence of structural configurations more complex than substitution as well as hole-doping.Comment: 5 pages, accepted in PR

Observation of magnetic edge state in graphene nanoribbons

"The electronic structure and spin magnetism for few-layer-graphene nanoribbons synthesized by chemical vapor deposition have been investigated using near-edge x-ray absorption fine structure (NEXAFS) and electron-spin resonance (ESR). For the pristine sample, a prepeak was observed below the pi* peak close to the Fermi level in NEXAFS, indicating the presence of additional electronic states close to the Fermi level. The intensity of this prepeak decreased with increasing annealing temperature and disappeared after annealing above 1500 degrees C. The ESR spectra, which proved the presence of localized spins, tracked the annealing-temperature-dependent behavior of the prepeak with fidelity. The NEXAFS and ESR results jointly confirm the existence of a magnetic edge state that originates from open nanographene edges. The disappearance of the edge state after annealing at higher temperatures is explained by the decrease in the population of open edges owing to loop formation of adjacent graphene edges.

Identification of individual and few layers of WS2 using Raman Spectroscopy

"The Raman scattering of single-and few-layered WS2 is studied as a function of the number of S-W-S layers and the excitation wavelength in the visible range (488, 514 and 647 nm). For the three excitation wavelengths used in this study, the frequency of the A(1g)(C) phonon mode monotonically decreases with the number of layers. For single-layer WS2, the 514.5 nm laser excitation generates a second-order Raman resonance involving the longitudinal acoustic mode (LA(M)). This resonance results from a coupling between the electronic band structure and lattice vibrations. First-principles calculations were used to determine the electronic and phonon band structures of single-layer and bulk WS2. The reduced intensity of the 2LA mode was then computed, as a function of the laser wavelength, from the fourth-order Fermi golden rule. Our observations establish an unambiguous and nondestructive Raman fingerprint for identifying single-and few-layered WS2 films.

Strain- and Adsorption-Dependent Electronic States and Transport or Localization in Graphene

The chapter generalizes results on influence of uniaxial strain and adsorption on the electron states and charge transport or localization in graphene with different configurations of imperfections (point defects): resonant (neutral) adsorbed atoms either oxygen- or hydrogen-containing molecules or functional groups, vacancies or substitutional atoms, charged impurity atoms or molecules, and distortions. To observe electronic properties of graphene-admolecules system, we applied electron paramagnetic resonance technique in a broad temperature range for graphene oxides as a good basis for understanding the electrotransport properties of other active carbons. Applied technique allowed observation of possible metal-insulator transition and sorption pumping effect as well as discussion of results in relation to the granular metal model. The electronic and transport properties are calculated within the framework of the tight-binding model along with the Kubo-Greenwood quantum-mechanical formalism. Depending on electron density and type of the sites, the conductivity for correlated and ordered adsorbates is found to be enhanced in dozens of times as compared to the cases of their random distribution. In case of the uniaxially strained graphene, the presence of point defects counteracts against or contributes to the band-gap opening according to their configurations. The band-gap behaviour is found to be nonmonotonic with strain in case of a simultaneous action of defect ordering and zigzag deformation. The amount of localized charge carriers (spins) is found to be correlated with the content of adsorbed centres responsible for the formation of potential barriers and, in turn, for the localization effects. Physical and chemical states of graphene edges, especially at a uniaxial strain along one of them, play a crucial role in electrical transport phenomena in graphene-based materials.Comment: 16 pages, 10 figure

Carbon nanotube-Cu hybrids enhanced catalytic activity in aqueous media

V. González, O. Martín and J. Baselga wish to thank Ministerio de Economía y Competitividad for funding through Grant MAT2010-17091. Authors also wish to thank to Sofía M. Vega for XPS measurements, Juan P. Fernández for TGA measurements and Lakshmy Pulickal Rajukumar for EDX measurements. C. Martín-Alberca thanks the University of Alcalá for his pre-doctoral Grant

Synthesis and new properties of nanostructured zinc oxide, carbon and other layered materials.

Tesis (Doctorado en Nanociencias y Materiales)"Existe una gran expectativa de que la Nanotecnologia impacte de manera positiva la calidad de vida a través de las nuevas aplicaciones que se deriven de esta.Dichas aplicaciones estarán basadas en fenómenos y características de los materiales que sólo es posible encontrar a escalas nanométricas. Quizas las más importantes aplicaciones sean en 1) medicina, desde mejores herramientas de diagnóstico, hasta mejores medicinas con blancos específicos y hechas a la medida; 2) en problemas de alto impacto social,como remediación de agua, aire y suelo; 3) en materiales para fuentes alternas de energía; y 4) en la industria de semiconductores para sostener la llamada Ley de Moore del escalamiento del tamaño y la capacidad de los elementos de procesamiento.en este trabajo de tesis se han atendido problemas específicos que de alguna u otra manera contribuyen al desarrollo de las aplicaciones esperadas de la Nanotecnologia. En particular,se ha contribuido al desarrollo de dos áreas principalmente: 1) la ciencia del óxido de zinc a nanoescala, y 2) la ciencia del carbono a nanoescala. El carbono, sin lugar a dudas, es el material que más ha sido estudiado en el área de Nanociencias y Nanotecnología, debido, en parte, a la flexibilidad de su química. Tal vez, el segundo material más estudiado es el óxido de zinc (ZnO). Esto es debido a la combinación de sus propiedades: es un semiconductor de brecha prohibida ancha con propiedades ópticas interesantes; presenta propiedades mecánicas interesantes; y es, en principio, un material inofensivo para la salud humana y para el medio ambiente. En este trabajo se optimizó la síntesis de nanoestructuras de ZnO en una dimensión utiliznado un método limpio de baja temperatura y de bajo costo. Esta técnica de síntesis y este material se utilizó para hacer un compósito de ZnO con celulosa, de cual se investigaron sus propiedades piezoeléctricas y piroeléctricas. Los dispositivos construidos a partir de este material compósito son capaces de generar energía eléctrica cuando se someten a excitación mecánica por medio de ondas ultrasónicas, o a gradientes de temperatura.""Nanotechnology is espected to impact the quality of life through many of the novel applications that it will enable. These applications will take advantage of features that are only feasible at the nanoscale. The most important applications are in medicine from better tools for diagnosis, to improved, customΙmade, and specifically targeted drugs; in problems of high social impact such as water, air and soil remediation, and alternative sources of renewable energy; and in the semiconductor industry to try to keep up with the soΙcalled Moore´s Law of the scaling of the size and power of processing units. In this Thesis work we have addressed punctual problems that in some way or another try to contribute to the development of the expected applications of nanotechnology. In particular, we have contributed to the development of mainly two areas: 1) nanoscale !inc oxide science, and Β) nanoscale carbon science. Carbon is, without a doubt, the material which has the most intense research activity in nanoscience and nanotechnology, because of its flexible chemistry. The second most studied material in nanoscience and nanotechnology is probably zinc oxide (ZnO). This is due to the combination of mainly three facts: it is a wide band gap semiconductor with interesting optical properties; it has interesting mechanical properties; and it is, in principle, innocuous to human health and to the environment. We optimi!ed a method for the synthesis of ZnO nanorods using a low temperature, low cost and clean approach. We used this material to make a composite with cellulose and probed its pie!oelectric and pyroelectric response. The constructed devices are capable of generating electricitt when excited with ultrasonic waves or temperature gradients. Through first principles calculations, we have contributed to the understanding of ferromagnetism in non-doped ZnO and in ZnO doped with nonΙmagnetic atoms; Our results suggest that the observed properties are very sensitive to the environment of the atoms at the surface.

Gastrópodos asociados al cultivo del berro (Nasturtium officinale, R. Brown) en condiciones de organoponía semiprotegida

They were carried out weekly samplings in areas of berro (N. officinale) in semi protected conditions of the agricultural enterprise in the municipality Las Tunas in the Las Tunas province from January until april of year 2019 to compare the most excellent characteristics in the behavior of the principal gastropods pest under that conditions of production. Besides including two areas in the periphery Las Tunas city for determined the producer’s perception about the principal phyto protection aspect. The gastropods species that impinged in the experimental areas were Subulina octona Brug. and Praticolella griseola (Pfeiffer). The population index obtain to correlation with the middle value of the temperature and relative humidity with de lineal regression and correlation employing the statist pack InfoStat version 16. In the experience relative humidity and temperatures favouring the population development of the gastropods objet the observation. The major infestation index corresponding to S. octona and P. griseola, two species havened a special behaviour type al azar. Producers haven’t culture for the crop protectionSe realizaron muestreos semanales en áreas semiprotegidas de berro (N. officinale) en la Empresa Agrícola Las Tunas en el municipio Las Tunas de la provincia de Las Tunas desde el mes de enero, hasta el mes de abril del año 2019 para comparar las características más sobresalientes del comportamiento poblacional de los principales gastrópodos plaga asociados al cultivo en esas condiciones de producción. Además, se incluyeron dos áreas en la periferia de la ciudad de Las Tunas para determinar la percepción de los productores sobre los principales aspectos de su fitoprotección. Las especies de gastrópodos que incidieron en el área experimental fueron Subulina octona Brug. y Praticolella griseola (Pfeiffer). Los índices poblacionales obtenidos se correlacionaron con los valores de las temperaturas medias, humedad relativa y precipitaciones a través de análisis de correlación y regresión lineal y se empleó para ello el paquete estadístico InfoStat, versión 16. En la experiencia se encontró que la humedad relativa y las temperaturas favorecieron el desarrollo poblacional de los gastrópodos objeto de observación. Los mayores índices de infestación correspondieron a S. octona y P. griseola, ambas especies tuvieron un comportamiento espacial de tipo al azar. Los productores carecen de cultura para la protección del cultivo