Normal Approximations of Regular Curves and Surfaces

YesBezier curves and surfaces are two very useful tools in Geometric Modeling, with many applications. In this paper, we will offer a new method to provide approximations of regular curves and surfaces by Bezier ones, with the corresponding examples

The curvature tensor of (\ka,\mu,\nu)-contact metric manifolds

We study the Riemann curvature tensor of (\kappa,\mu,\nu)-contact metric manifolds, which we prove to be completely determined in dimension 3, and we observe how it is affected by D_a-homothetic deformations. This prompts the definition and study of generalized (\kappa,\mu,\nu)-space forms and of the necessary and sufficient conditions for them to be conformally flat

SÍNTESIS Y CARACTERIZACIÓN DE COMPUESTOS DE COORDINACIÓN: UNA

El presente trabajo muestra los resultados exitosos en el desarrollo de un curso de laboratorio de química inorgánica mediante la implementación del modelo de Aprendizaje por Investigación, como una estrategia integradora de conocimientos que permite a los estudiantes el desarrollo de competencias de reconocimiento, interpretación y producción relacionadas con los procesos de síntesis de compuestos de coordinación de interés en el área de la química inorgánica. El desarrollo riguroso de la metodología científica condujo a la comprensión y aplicación de las teorías de enlace de valencia y orbital molecular, la teoría de coordinación de Werner y la teoría de campo cristalino; como también principios de simetría, teoría de grupos y espectroscopía infrarroja, IR

Modelling and Simulation of Lily flowers using PDE Surfaces

This paper presents a partial differential equation (PDE)-based surface modelling and simulation framework for lily flowers. We use a PDE-based surface modelling technique to represent shape of a lily flower and PDE-based dynamic simulation to animate blossom and decay processes of lily flowers. To this aim, we first automatically construct the geometry of lily flowers from photos to obtain feature curves. Second, we apply a PDE-based surface modelling technique to generate sweeping surfaces to obtain geometric models of the flowers. Then, we use a physics-driven and data-based method and introduce the flower shapes at the initial and final positions into our proposed dynamic deformation model to generate a realistic deformation of flower blossom and decay. The results demonstrate that our proposed technique can create realistic flower models and their movements and shape changes against time efficiently with a small data size

INFLUENCE OF CERIUM ADDITION ON THE SYNTHESIS OF SOLIDS BASED ON PLATINUM SUPPORTED OVER ALUMINA-PILLARED CLAY

The present work shows the preparation and characterization of a set of solids by modification of a natural clay with Al, Ce and Pt. The characterization of the solids by X-ray diffraction (XRD) reveals the insertion of alumina pillars, whereas the subsequent impregnations of the pillared clay with Pt (II) or Ce (IV) do not lead to structural variations that can be observed by XRD. The characterization by nitrogen adsorption indicates that the incorporation of platinum species originates damages in the microporosity of the solid, while the addition of cerium prevents the deterioration of the textural propertie

Generalized (\kappa,\mu)-space forms

Generalized (\kappa ,\mu)-space forms are introduced and studied. We examine in depth the contact metric case and present examples for all possible dimensions. We also analyse the trans-Sasakian case.Comment: 20 pages, several changes have been done in this versio

Efecto de la Temperatura de Calcinación en las Propiedades Texturales y Estructurales de Fe(III)-TiO2

El dopaje del dióxido de titanio (TiO2) con iones de metales de transición, como el Fe3+, es uno de los mé­todos empleados para modificar las propiedades físicas y químicas de este material. En este trabajo se analizó la influencia de la temperatura de calcinación en las propiedades texturales y estructurales del dióxido de tita­nio dopado con Fe3+, Fe(III)-TiO2, sintetizado a partir del mineral ilmenita mediante un proceso de extracción con ácido sulfúrico. El material sintetizado fue caracterizado por fluorescencia de rayos X, difracción de rayos X, espectroscopía infrarroja e isotermas de adsorción-desorción de nitrógeno a 77 K. El Fe(III)-TiO2 sintetizado mostró la fase anatasa como único componente cristalino, con buena estabilidad térmica a 700 °C, revelando la sustitución isomórfica de hierro en la estructura del TiO2. Las distribuciones de tamaños de poros del Fe(III)- TiO2 tratado a 400, 500, 600 y 700 °C mostraron un comportamiento monomodal con máxima población en la región de los mesoporos. El aumento de la temperatura de calcinación del Fe(III)-TiO2 condujo a la formación de estructuras sólidas con mayores radios de poros

Transitional palliative care interventions for older adults with advanced non-malignant diseases and frailty: a systematic review

Purpose: To identify transitional palliative care (TPC) interventions for older adults with non-malignant chronic diseases and complex conditions. Design/methodology/approach: A systematic review of the literature was conducted. CINAHL, Cochrane Library, Embase and Pubmed databases were searched for studies reporting TPC interventions for older adults, published between 2002 and 2019. The Crowe Critical Appraisal Tool was used for quality appraisal. Findings: A total of six studies were included. Outcomes related to TPC interventions were grouped into three categories: healthcare system-related outcomes (rehospitalisation, length of stay [LOS] and emergency department [ED] visits), patient-related outcomes and family/carer important outcomes. Overall, TPC interventions were associated with lower readmission rates and LOS, improved quality of life and better decision-making concerning hospice care among families. Outcomes for ED visits were unclear. Research limitations/implications: Positive outcomes related to healthcare services (including readmissions and LOS), patients (quality of life) and families (decision-making) were reported. However, the number of studies supporting the evidence were limited. Originality/value: Studies examining the effectiveness of existing care models to support transitions for those in need of palliative care are limited. This systematic literature review identified and appraised interventions aimed at improving transitions to palliative care in older adults with advanced non-malignant diseases or frailty