SOLID STATE MORPHOLOGY AND SIZE TUNING OF NANOSTRUCTURED PLATINUM USING MACROMOLECULAR COMPLEXES

Indexación: Web of Science; Scielo.The macromolecular complexes Chitosan●(PtCl2)n and PSP-co-4-PVP●(PtCl2)n, were prepared from the respective polymer and PtCl2 in metal:polymer molar ratios 1:1 and 1:5. Pyrolisis of the macromolecular complexes Chitosan●(PtCl2)n and PSP-co-4-PVP●(PtCl2)n at 800 °C under air affords cubic nanostructured Pt in the pure phase. The morphology of the pyrolityc products depends on the molar metal:polymer ratio; i.e. a "cotton" 3D shape for the 1:1 ratio and a 'foamy" 3D shape for the 1:5 ratio. On the other hand, the particle size depends on the polymer nature, obtaining Pt nanoparticles as small as 6 nm for the chitosan precursors in both molar ratio.http://ref.scielo.org/8p5h2

On the properties of discrete spatial filters for CFD

© 2016. This version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The spatial filtering of variables in the context of Computational Fluid Dynamics (CFD) is a common practice. Most of the discrete filters used in CFD simulations are locally accurate models of continuous operators. However, when filters are adaptative, i.e. the filter width is not constant, or meshes are irregular, discrete filters sometimes break relevant global properties of the continuous models they are based on. For example, the principle of maxima and minima reduction or conservation are eventually infringed. In this paper, we analyze the properties of analytic continuous convolution filters and extract those we consider to define filtering. Then, we impose the accomplishment of these properties on explicit discrete filters by means of constraints. Three filters satisfying the derived conditions are deduced and compared to common differential discrete CFD filters on synthetic fields. Tests on the developed discrete filters show the fulfillment of the imposed properties. In particular, the problem of maxima and minima generation is resolved for physically relevant cases. The tests are conducted on the basis of the eigenvectors of graph Laplacian matrices of meshes. Thus, insight into the relations between filtering and oscillation growth on general meshes is provided. Further tests on singularity fields and on isentropic vortices have also been conducted to evaluate the performance of filters on basic CFD fields. Results confirm that imposing the proposed conditions makes discrete filters properties consistent with those of the continuous ones.Peer ReviewedPostprint (author's final draft

Evaluación de resultados del cerclaje con cinta de Dacrón (Cervi-Set), en pacientes con luxación acromio-clavicular. Hospital Universitario Clínica San Rafael. (2005 - 2007)

Las lesiones de la articulación acromio-clavicular son frecuentes en el servicio de urgencias en traumatismo de hombros, entre estas lesiones es frecuente la luxación acromio-clavicular, se realiza tratamiento quirúrgico en los pacientes clasificados como grado III de Allman. (2-3) se han descrito múltiples técnicas de manejo quirúrgico, el método que evaluamos es una reparación coraco-clavicular extraarticular, de las cuales se encuentran descritas múltiples técnicas de fijación con uso de tornillos coraco-claviculares, transferencias tendinosas, paso de asas coraco-claviculares sintéticas o metálicas, Realizamos reducción abierta y fijación con cerclaje con cinta de Dacrón (Cervi-Set). El propósito del estudio fue describir los resultados postoperatorios de los pacientes con luxación acromio-clavicular grado III en cuanto a dolor residual, funcionalidad del hombro y días promedio de incapacidad. Tomamos para la medición de los resultados postoperatorios el sistema de Constant-Murley Shoulder Score para el estudio del hombro la cual se utiliza para evaluar la función general del hombro, tanto de forma objetiva como subjetiva . La valoración del dolor residual se realizo con la escala visual análoga para evaluación del dolor, y los días de incapacidad laboral según lo referido por el paciente. El diseño del estudio es observacional descriptivo retrospectivo. Se evaluaron 33 pacientes con luxación acromio-clavicular de los cuales 30 (90,01%) correspondían a hombres y 3 (9,09%) mujeres. El rango promedio de edad de realización del procedimiento quirúrgico de los pacientes era de 34.27 años (15-71 años). El tiempo promedio de evaluación de los pacientes después de realización del procedimiento quirúrgico fue de 28.6 meses (13-47 meses). Se encontró dolor en la evaluación final de los residual en el hombro intervenido quirúrgicamente en 15 (45.45%) pacientes entre leve y moderado, ninguno de los paciente refirió dolor severo. resultados de la escala de Constant-Murley shoulder score para lesiones de hombro, encontramos resultados excelentes (90-100 puntos) en 29 (75,75%) de los paciente, Buenos (80-89 puntos) en 4 (12,12%) de los paciente, encontramos una mediana de 95 puntos. El promedio de días de incapacidad de los pacientes fue de 66.3 días con un rango entre 30-120 días de incapacidad y una mediana de 60 días. Como conclusión encontramos que la realización de fijación coraco-clavicular con cerclaje con cinta de Dacrón (Cervi-Set) en pacientes con luxación acromio-clavicular es un procedimiento con resultados clínicos postoperatorios buenos a excelentes que presenta una baja tasa de complicaciones postoperatorias y una recuperación funcional y dolor residual mínimo en la articulación acromio-clavicular, la técnica quirúrgica es sencilla, de bajo costo, presenta un promedio de incapacidades postoperatorias que se encuentra entre el promedio de la incapacidad laboral de los pacientes a quienes se les realiza otros tipos de procedimientos quirúrgico

EXCURSIÓN FAMILIAR [Material gráfico]

ÁLBUM FAMILIAR CASA DE COLÓNCopia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201

On the extension of LES methods from incompressible to compressible turbulent flows with application to turbulent channel flow

Published under licence in Journal of Physics: Conference Series by IOP Publishing Ltd. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.The objective of the present work is to validate the compressible Large-Eddy Simulation (LES) models implemented in the in house parallel unstructured CFD code TermoFluids. Our research team has implemented and tested several LES models over the past years for the incompressible regimen. In order to be able to solve complex turbulent compressible flows, the models are revisited and modified if necessary. In addition, the performance of the implemented hybrid advection scheme is an issue of interest for the numerical simulation of turbulent compressible flows. The models are tested in the well known turbulent channel flow problem at different compressible regimens.Peer ReviewedPostprint (published version

Emergency Medical Service Ambulance System Planning: History and Models

Integer linear programming models that incorporate probabilistic and stochastic components represent one approach for capturing the stochastic nature of emergency medical service ambulance systems. This includes modeling non-deterministic call arrival and servicing rates and congestion in the ambulance network (i.e., ambulance unavailability). These models focus on maximizing the total population that can find an available ambulance within a set service time standard (s) with a probability of at least α%. In MALP the concept of local vehicle busyness estimates is introduced to estimate the availability of service in a neighborhood given the neighborhood’s level of demand and the number of ambulance vehicles located in the neighborhood. QMALP is an extension of MALP where queue-theory derived parameters are implemented in the MALP model framework in order to relax the assumption that the probability of different ambulances being busy are independent. Despite this considerable development, several concerns remained about MALP and QMALP, namely the districting assumption where its assumed that a neighborhood’s calls for service are served only by an ambulance in the area, that ambulances in a neighborhood only serve calls for service originating within the neighborhood, or that at least the flow of ambulance service to and from external neighborhoods was roughly equal. Questions have been raised about the validity of MALP and QMALP’s reliability estimates, that is, whether a neighborhood actually received α-reliable service.To address these issues, we developed the Resource-Constrained Queue-based Maximum Availability Location Problem (RC-QMALP). This model is based on a location-allocation framework that (1) assigns workload from neighborhoods to ambulances located within s and ambulance idle capacity to neighborhoods and (2) includes additional constraints designed to help ensure the validity of the original MALP and QMALP constraints used to establish whether a neighborhood can find an available ambulance with α-reliability. We also implemented a secondary minsum objective that minimizes the average travel distance between ambulances and the neighborhoods they service while maintaining the priority of the MALP and QMALP coverage objective.In this thesis, we validated RC-QMALP by comparing the reliable coverage levels predicted by the RC-QMALP to the ambulance system simulations that used the locational configurations suggested by the RC-QMALP. We found that MALP 2 and QMALP provided higher levels of reliable coverage and that RC-QMALP’s secondary objective has a negligible impact on system performance. However, RC-QMALP-based models provide more accurate estimates of reliable coverage and location solutions whose simulated reliable coverage performance was always within 5% of the optimal solution with the same system parameters (we tested 1,080 different model configurations). Our work suggests that (1) simulation models must be developed to handle the modeling assumptions that underlie location optimization models and that (2) service reliability location models should consider additional factors such as ambulance workloads (and their distribution)

The scars of civil war: the long-term welfare effects of the Salvadoran armed conflict

This paper estimates the long-term effects on human capital accumulation and subsequent labor market outcomes of in utero and early childhood exposure to the civil war in El Salvador (1980–92), the second longest and deadliest civil conflict in Central America. Identification is obtained from spatial and intertemporal variation in the intensity of the conflict drawn from historical archive data comprising records of human casualties, disappearances, and refugees. The results show that people born in highly violent areas during the civil war saw a reduction in their probability of being employed by 6 percentage points, and of getting a high-skilled job by 5 percentage points, 20 to 30 years hence. The civil war also reduced their education by 0.8 year, as well as their enrollment and literacy rates. Subgroup analysis indicates that exposed males and indigenous groups experienced the largest losses in human capital and had weaker performance in the labor market

Seguridad, salud en el trabajo y el desempeño laboral de trabajadores de mantenimiento estructural de hospitales estatales Lima Sur, 2023

El presente estudio posee como propósito determinar la relación entre la seguridad, salud en el trabajo con el desempeño laboral de los trabajadores de mantenimiento estructural de un hospital estatal, Lima sur 2023. Posee un tipo de investigación básica con enfoque cuantitativo y de diseño no experimental correlacional. Se aplicó una encuesta como técnica a una muestra de 80 trabajadores con un cuestionario como instrumento validado por expertos. Se concluyó que un 41% de los entrevistados que consideraron altas deficiencia en la aplicación de la seguridad en el trabajo, el 49% señala que la aplicación de seguridad es bajo-medio, no siendo perfecto, pero requiere mejoras y solo un 10% considera que hay baja aplicación por lo que demostró que existe relación significativa entre la seguridad y salud en el trabajo y el desempeño laboral de los trabajadores de acuerdo a los datos del estadístico de Rho Spearman que mostraron un valor de 0.568 con una representación positivamente moderada relacionada con los valores de p menores a 0.05

Tuberías de polipropileno para la optimización del sistema de instalaciones sanitarias del hospital María Auxiliadora, Lima 2020

La presente tesis tiene como objetivo principal determinar cómo influye las tuberías de polipropileno en la optimización del sistema de instalaciones sanitarias de agua fría, caliente, blanda, desagüe, y agua contra incendio del hospital María Auxiliadora, Lima 2020. El objetivo de la investigación fue determinar cómo influye las tuberías de polipropileno en Para la optimización del diseño de las instalaciones sanitarias de la edificación hospitalaria se utilizó como base el Reglamento Nacional de Edificaciones, en la norma IS 010, así como en otras normas internacionales. El tipo de estudio es aplicado con un enfoque cuantitativo y diseño no experimental transeccional con alcance descriptivo correlacional-causal, porque no se manipularán las variables, solo se describirá y analizará su comportamiento en un momento dado, así como relación de causa y efecto entre las mismas