RESUMO
Cassava starch solid biopolymer electrolyte (SBPE) films were prepared by a thermochemical method with different concentrations of lithium triflate (LiTFT) as a dopant salt. The process began with dispersing cassava starch in water, followed by heating to facilitate gelatinization; subsequently, plasticizers and LiTFT were added at differing concentrations. The infrared spectroscopy analysis (FTIR-ATR) showed variations in the wavenumber of some characteristic bands of starch, thus evidencing the interaction between the LiTFT salt and biopolymeric matrix. The short-range crystallinity index, determined by the ratio of COH to COC bands, exhibited the highest crystallinity in the salt-free SBPEs and the lowest in the SBPEs with a concentration ratio (Xm) of 0.17. The thermogravimetric analysis demonstrated that the salt addition increased the dehydration process temperature by 5 °C. Additionally, the thermal decomposition processes were shown at lower temperatures after the addition of the LiTFT salt into the SBPEs. The differential scanning calorimetry showed that the addition of the salt affected the endothermic process related to the degradation of the packing of the starch molecules, which occurred at 70 °C in the salt-free SBPEs and at lower temperatures (2 or 3 °C less) in the films that contained the LiTFT salt at different concentrations. The cyclic voltammetry analysis of the SBPE films identified the redox processes of the glucose units in all the samples, with observed differences in peak potentials (Ep) and peak currents (Ip) across various salt concentrations. Electrochemical impedance spectroscopy was used to establish the equivalent circuit model Rf-(Cdl/(Rct-(CPE/Rre))) and determine the electrochemical parameters, revealing a higher conduction value of 2.72 × 10-3 S cm-1 for the SBPEs with Xm = 17 and a lower conduction of 5.80 × 10-4 S cm-1 in the salt-free SBPEs. It was concluded that the concentration of LiTFT salt in the cassava starch SBPE films influences their morphology and slightly reduces their thermal stability. Furthermore, the electrochemical behavior is affected in terms of variations in the redox potentials of the glucose units of the biopolymer and in their ionic conductivity.
Assuntos
Condutividade Elétrica , Eletrólitos , Manihot , Amido , Amido/química , Manihot/química , Eletrólitos/química , Termogravimetria , Biopolímeros/química , Mesilatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Varredura Diferencial de CalorimetriaRESUMO
Resumen Introducción: Son escasos los datos del impacto de la infección por el virus de inmunodeficiencia humana (VIH) a nivel hormonal, metabólico y hematológico en pacientes hospitalizados en Colombia. Objetivo: Describir el perfil hormonal, metabólico y hematológico de los pacientes con VIH hospitalizados en una institución de tercer nivel. Material y método: Estudio observacional de corte transversal, donde se incluyeron variables sociodemográficas, clínicas, hormonales, metabólicas y hematológicas de pacientes con VIH entre el 2013 y 2014. Resultados: Se incluyeron 52 pacientes, 34 hombres, con media de edad 39,7 años (Ds 12,6, Min: 21 Max: 79). 23% habían cursado con tuberculosis, 13% con toxoplasmosis cerebral. 26 pacientes tenían historia de consumo de tóxicos: cigarrillo (58%), alcohol (27%) y sustancias alucinógenas (15%). 14% de los pacientes recibían terapia antirretroviral al ingreso, los esquemas contenían principalmente inhibidores de proteasa. Otros medicamentos usados fueron: trimetoprim-sulfametoxazol (27.2%) y antituberculosos (15%). Las principales causas de hospitalización fueron toxoplasmosis cerebral (31%) y tuberculosis (15%). 52% de la población presentó síndrome de desgaste. El tiempo de diagnóstico del VIH fue <1 de un año en el 48% de la población. 79% de los pacientes tenía recuento de CD4 <200cel/mm3 (Ds 199, Min: 3 Max: 641). En el perfil hormonal, 58% (29 pacientes) presentaron alteración del eje tiroideo, de los cuales 14 presentaron perfil de hipotiroidismo central. 55,8% de los hombres presentaron hiperprolactinemia. El perfil metabólico se caracterizó por hipertrigliceridemia (44%) y HDL bajas (81%). La alteración electrolítica de mayor frecuencia fue hiponatremia (37%). Conclusiones: En la población de pacientes hospitalizados con VIH, se encontraron alteraciones endocrinas que sugieren compromiso glandular primario hipofisiario y adrenal; alteraciones lipídicas y electrolíticas en gran medida relacionadas con enfermedad avanzada.
Abstract Introduction: Data on the impact of human immunodeficiency virus (HIV) infection on a hormonal, metabolic and haematological level in patients hospitalized in Colombia are scarce. Objective: To describe the hormonal, metabolic and haematological profile of HIV patients hospitalized in a third level institution. Material and method: Cross-sectional observational study, which included sociodemographic, clinical, hormonal, metabolic and hematological variables of patients with HIV between 2013 and 2014. Results: We included 52 patients, 34 men, with an average age of 40 years (SD 12.6, Min: 21 Max: 79). 23% had tuberculosis, 13% had cerebral toxoplasmosis. 26 patients had a history of toxic consumption: cigarette (58%), alcohol (27%) and hallucinogenic substances (15%). 14% of the patients received antiretroviral therapy at admission, mainly with protease inhibitors. Other medications used were: trimethoprim-sulfamethoxazole (27.2%) and antituberculous drugs (15%). The main causes of hospitalization were cerebral toxoplasmosis (31%) and tuberculosis (15%). 52% of the population had Wasting syndrome. The time of diagnosis of HIV was <1 year in 48% of the population. 79% of the patients had a CD4 count <200 cell/mm3 (SD 199, Min: 3 Max: 641). In the hormonal profile, 58% (29 patients) presented alteration of the thyroid axis, of which 14 session profile of central hypothyroidism. 55.8% of men had hyperprolactinemia. The metabolic profile was characterized by hypertriglyceridemia (44%) and low HDL (81%). The most frequent electrolyte alteration was hyponatremia (37%). Conclusions: In the population of patients hospitalized with HIV, endocrine alterations were found suggesting primary glandular, pituitary and adrenal involvement, with lipid and electrolyte alterations largely related to advanced disease.
Assuntos
Humanos , HIV , Colômbia , Eletrólitos , Hormônios , HospitalizaçãoRESUMO
We propose a novel approach for the reconstruction of urban structures from 3D point clouds with an assumption of Manhattan World (MW) building geometry; i.e., the predominance of three mutually orthogonal directions in the scene. Our approach works in two steps. First, the input points are classified according to the MW assumption into four local shape types: walls, edges, corners, and edge corners. The classified points are organized into a connected set of clusters from which a volume description is extracted. The MW assumption allows us to robustly identify the fundamental shape types, describe the volumes within the bounding box, and reconstruct visible and occluded parts of the sampled structure. We show results of our reconstruction that has been applied to several synthetic and real-world 3D point data sets of various densities and from multiple viewpoints. Our method automatically reconstructs 3D building models from up to 10 million points in 10 to 60 seconds.
RESUMO
Urban simulation models and their visualization are used to help regional planning agencies evaluate alternative transportation investments, land use regulations, and environmental protection policies. Typical urban simulations provide spatially distributed data about number of inhabitants, land prices, traffic, and other variables. In this article, we build on a synergy of urban simulation, urban visualization, and computer graphics to automatically infer an urban layout for any time step of the simulation sequence. In addition to standard visualization tools, our method gathers data of the original street network, parcels, and aerial imagery and uses the available simulation results to infer changes to the original urban layout and produce a new and plausible layout for the simulation results. In contrast with previous work, our approach automatically updates the layout based on changes in the simulation data and thus can scale to a large simulation over many years. The method in this article offers a substantial step forward in building integrated visualization and behavioral simulation systems for use in community visioning, planning, and policy analysis. We demonstrate our method on several real cases using a 200 GB database for a 16,300 km2 area surrounding Seattle.