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CDRIME-MTIS: An enhanced rime optimization-driven multi-threshold segmentation for COVID-19 X-ray images
No full textTo improve the detection of COVID-19, this paper researches and proposes an effective swarm intelligence algorithm-driven multi-threshold image segmentation (MTIS) method. First, this paper proposes a novel RIME structure integrating the Co-adaptive hunting and dispersed foraging strategies, called CDRIME. Specifically, the Co-adaptive hunting strategy works in coordination with the basic search rules of RIME at the individual level, which not only facilitates the algorithm to explore the global optimal solution but also enriches the population diversity to a certain extent. The dispersed foraging strategy further enriches the population diversity to help the algorithm break the limitation of local search and thus obtain better convergence. Then, on this basis, a new multi-threshold image segmentation method is proposed by combining the 2D non-local histogram with 2D Kapur entropy, called CDRIME-MTIS. Finally, the results of experiments based on IEEE CEC2017, IEEE CEC2019, and IEEE CEC2022 demonstrate that CDRIME has superior performance than some other basic, advanced, and state-of-the-art algorithms in terms of global search, convergence performance, and escape from local optimality. Meanwhile, the segmentation experiments on COVID-19 X-ray images demonstrate that CDRIME is more advantageous than RIME and other peers in terms of segmentation effect and adaptability to different threshold levels. In conclusion, the proposed CDRIME significantly enhances the global optimization performance and image segmentation of RIME and has great potential to improve COVID-19 diagnosis
Applying a green solvent with microwave, ultrasound, and soxhlet extraction techniques to quantify the slip additive cis-1,3-docosenamide and nine oxidative degradation byproducts in polypropylene samples
No full textErucamide is used as an important slip agent for polymers. However, erucamide can degrade during processing and long-term storage, forming various oxidation products. These degradation products can affect the recovery rates of erucamide. In this study, investigated different solid–liquid extraction methods (Soxhlet, microwave, and ultrasound) and used gas chromatography with mass spectrometry (GC-MS) to quantify erucamide and its degradation byproducts in polypropylene (PP). A multivariable experiment was designed, and a mixed-effect approach was used to analyze the results. Various extraction variables were examined, such as temperature, time, solvents, and PP pretreatments. Using a mixed-effect model with a Kenward–Roger approximation, an R2 of the model of 97% and p values of 0.168, 0.000, and 0.000 were obtained for the technical, solvent, and type of PP pretreatment variables, respectively. The highest average recoveries of erucamide were found with the microwave technique and were 96.4% using dichloromethane, 94.57% using cyclohexane, and 93.05% using limonene. With ultrasound, recoveries ranged between 85 and 92% for dichloromethane and limonene. In addition, it was observed that the extraction method had better recovery results in ground PP than in films and in pellets. Nine oxidative degradation byproducts of erucamide were identified and semi-quantified by GC-MS. The reaction mechanisms for forming each byproduct were proposed. The byproducts that experienced a higher rate of degradation of erucamide were erucamide with a hydroxyl group at position one and 12-amino-6-12-oxo-dodecanoic acid, showing more prominent peaks using the Soxhlet method with cyclohexane and dichloromethane as solvents and polypropylene (PP) films as the type of material used
EcoMCS: a project management application through management control systems for residential construction firms in Colombia
No full textThis research article aims to introduce a novel project management application, denominated EcoMCS, based on Management Control Systems (MCS) assessment to improve the performance of residential construction firms in Colombia. The study is grounded in the conceptualization of project management and MCS and builds upon an interview study conducted with managers of residential construction firms in the country. Our findings revealed that the economic dimension is the least developed, indicating a need for improvement. The project’s specific objectives include enhancing the MCS’s economic dimension, refining evaluation methods for goal fulfillment, implementing incentive programs, fostering decentralized decision-making, and nurturing human potential within residential construction firms. By addressing these objectives, the proposed EcoMCS application seeks to facilitate efficient and effective project management practices in the residential construction industry, ultimately contributing to more sustainable and cost-effective construction projects
CO130 Dyspnea and health-related quality of life in patients with persistent symptoms after at least six months of hospital discharge due to COVID-19
No full textObjectives. To evaluate dyspnea in patients with persistent symptoms after at least six months of hospital discharge due to COVID-19 and its correlation with the quality of life, fatigue, and functional status. Methods. This cross-sectional study included 101 patients with persistent symptoms after at least six months of hospital discharge for COVID-19. A physician evaluated dyspnea using the Modified Medical Research Council (mMRC) scale questionnaire, the quality of life with the EQ-5D-5L, fatigue with an analog scale (0=no fatigue to 10=worst possible fatigue), and functional status with the Post-COVID-19 Functional Status scale (grade 0=no limitation to grade 4=severe limitation). We used Fisher’s exact test for categorical data and the Wilcoxon rank-sum test for continuous data to assess differences across groups. Spearman’s test was used for correlations. The significance level was 5%. Results. Of the participants, 56.4 % (n=57) were women with a mean age of 57.7 (SD±16.3) years. The most reported symptoms were muscle weakness (61.4%, n=62), dyspnea (51.5%, n=52), muscle pain (49.5%, n=50), and fatigue 41 (40.6%, n=41). Seventy-two (71.3%) participants reported an increase in the mMRC dyspnea scale score, with no differences according to ICU requirements. Forty of the 81 (49.4%) participants with an mMRC grade 0 before COVID-19 reported a grade 3-4 during the medical visit. The EQ5D-5L index was 10% lower after COVID-19 (median difference: -0.01 points, interquartile range: -0.14 to -0.05), and those who required ICU admission had a more significant change in the index than those who did not (-0.12 vs -0.07, p=0.008). The mMRC grade reported during the medical visit was negatively correlated with the EQ5D-5L index (rho=-0.5836716, p<0.0001) and positively correlated with fatigue (rho=0.38,p =0.001) and functional status (rho=0.41,p <0.001). Conclusions. Dyspnea is prevalent among patients discharge for COVID-19 with persistent symptoms and may affect their quality of life and functional status
A novel cartoon crosslinked β-cyclodextrin (C-β-CD) polymer for effective uptake of Hg from aqueous solutions: Kinetics, equilibrium, thermodynamics, and statistical physics approach
No full textA novel cartoon crosslinked β-cyclodextrin (C-β-CD) polymer was obtained by crosslinking β-CD unities and cellulosic fibers of paper towel cardboard via esterification using citric acid. C-β-CD polymer was used as an adsorbent to uptake Hg from aqueous matrices, and kinetics, equilibrium, thermodynamics, and statistical physics were evaluated. It was found that the C-β-CD polymer was successfully synthesized and was a promising adsorbent to remove Hg from aqueous solution, achieving a removal percentage higher than 90 % and a maximum adsorption capacity of 211.3 mg g−1. The best operational adsorption conditions were a pH of 5.0, an adsorbent dosage of 0.5 g/L, 270 min, and 328 K. Besides, the pseudo-second-order model well-described the adsorption kinetics, and the Langmuir model better represented the equilibrium. The thermodynamic studies pointed to spontaneous and endothermic adsorption. The positive effect of the temperature on the process was also confirmed by the statistical physics approach, where the number of ions adsorbed per site increased with increasing temperature. It was suggested that electrostatic interaction was the main interaction mechanism responsible for the good performance of the novel C-β-CD polymer. In addition, the adsorbent proved to be effective for three adsorption cycles. Finally, it can be concluded that a novel C-β-CD adsorbent was prepared using an easy and green technique, and the obtained material is promising to separate Hg from contaminated waters
Nanoparticles generated during volcanic rock exploitation: an overview
Get PDFNanoparticles (NPs) from the mining of volcanic rocks have been a matter of concern around the world because they can pose environmental and human health risks. The nanoparticles are pointed as opportunities of application in a large field of knowledge. The aim of this study is to provide an overview of scientific publications on the success rates of mineral nanoparticles, the use of soil remineralizers as an alternative for replacing highly soluble fertilizers and their potential risk to human health and the environment. Nanoparticles were successful used as a filter agent and may act as carrier agent of metals and molecules through the environment compartments; rock powder was used as a litho-fertilizer in nature or enriched with nutrients and pesticides for plant disease control. However, nanoparticles were also identified as particle promoting of human diseases. Finally, this work addresses nanoparticles derived from volcanic rock mining and highlights the relevance of developing cleaner procedures to minimize exposure to these materials and is therefore of direct relevance to both the volcanic rock mining and agriculture sector and health.Gindri Ramos, Claudete-will be generated-orcid-0000-0003-2172-8052-600Silva Oliveira, Marcos LeandroFernández Pena, MerlysMeriño Cantillo, AndreaLozano Ayarza, Liliana Patricia-will be generated-orcid-0000-0001-5186-2864-600Korchagin, JacksonCampanhola Bortoluzzi, Edson-will be generated-orcid-0000-0002-0967-0057-60
Development of fibre-reinforced cementitious mortar with mineral wool and coconut fibre
No full textGlobally, as human population and industries grow, so does the creation of agricultural, industrial, and demolition waste. When these wastes are not properly recycled, reused, or disposed of, they pose a threat to the environment. The importance of this study lies in the beneficial use of coconut fibre and mineral wool in the form of fibres in cement mortar production. This study examines the use of coconut and mineral wool fibres in the production of fibre-reinforced mortar. Five different mortar mixtures were prepared, having one control mortar along with four fibre-reinforced mortars. The control mortar is denoted as CM while 1% and 1.5% of mineral wool are incorporated into this mortar mix and denoted as RMM-1.0 and RMM-1.5, respectively. Additionally, the mortar sample configurations contain 1% and 1.5% coconut fibers, designated as RCM-1.0 and RCM-1.5. These samples were subjected to different strength and durability tests to determine their suitability for use in mortar production. The testing findings show that mortar containing 1.5% mineral wool has better compared flexural strength and durability properties. The investigation results will form part of the database for the efficient utilization of natural and waste fibres in the construction and building sectors
Sentido de pertenencia: análisis de las dinámicas locales en la consolidación de la identidad y sentido de lugar en el centro histórico de Barranquilla
No full textEl patrimonio mantiene una estrecha relación entre generaciones cuyas características temporales continúan presentes y dan contexto a su cultura y sociedad, haciendo que su memoria sea más valiosa y su historia más grande. En el Centro histórico de Barranquilla se ha observado deterioro en algunos inmuebles arquitectónicos de carácter patrimonial, esto debido al poco sentido de pertenencia de los ciudadanos hacia la historia que representan las edificaciones, en las que diariamente transcurren y conviven los ciudadanos, y que son puntos culturalmente fuertes y de una representación histórica importante para Barranquilla. Esta investigación se centra en el análisis de dinámicas cotidianas en el Centro Histórico de Barranquilla, la comprensión e identificación de los disimiles factores que afectan la conservación de la identidad local y el sentido de lugar a treves con la pérdida de la apropiación de la ciudadanía barranquillera con su Centro histórico; mediante una metodología de enfoque cualitativo, donde se recolectó y analizó la información de datos, utilizando un método intuitivo fundamentado en observaciones e interpretaciones realizadas, partiendo del análisis de entrevistas realizadas a grupos de interés, generando como resultados, respuestas a las causas de los eventos y fenómenos físicos sociales que experimentó el Centro de Barranquilla. Como conclusión, se pudo establecer que la comunidad es un pilar fundamental en la preservación y conservación del estado de los inmuebles patrimoniales en las ciudades, pues es por medio de ellos que las tradiciones y la cultura cobran vida y se representan e identifican como ciudad misma.Heritage maintains a close relationship between generations whose temporary characteristics continue to be present and give context to their culture and society, making their memory more valuable and their history greater. In the historic center of Barranquilla, deterioration has been observed in some architectural properties of patrimonial character, this due to the little sense of belonging of the citizens towards the history represented by the buildings, in which citizens daily pass and coexist, and which are culturally strong points and of an important historical representation for Barranquilla. This research focuses on the analysis of daily dynamics in the Historic Center of Barranquilla, the understanding and identification of the different factors that affect the conservation of the local identity and the sense of place through the loss of the appropriation of the citizens of Barranquilla with their Historic Center; by means of a qualitative approach methodology, where the data information was collected and analyzed, using an intuitive method based on observations and interpretations made, starting from the analysis of interviews carried out with groups of interest, generating as results, answers to the causes of the events and physical social phenomena experienced by the Center of Barranquilla. As a conclusion, it was possible to establish that the community is a fundamental pillar in the preservation and conservation of the state of heritage properties in the cities, since it is through them that traditions and culture come to life and are represented and identified as the city itself.Resumen 4--Lista de tablas y figuras 8-- 1.Planteamiento del Problema 12-- 1.1. Pregunta problema 13-- 2Objetivos13-- 2.1. Objetivo general 13-- 2.2.Objetivos específicos 13 3. Justificación 13-- 4. Marco referencial 16-- 4.1. Estado del Arte 16 4.2.Marco teórico 22 --4.2.1. La cultura, una forma directa de los modos de vida 22--4.2.2. Noción de identidad24-- 4.2.3. La memoria como base de la identidad 25--4.2.4. Noción de Patrimonio 26--4.2.5. La conservación y el Centro Histórico de Barranquilla 27--4.3. Marco Legal 28-- 4.3.1.Cartas Internacionales 29--4.3.2. Organizaciones Internacionales 31-- 4.3.3. Decretos Nacionales 33-- 4.3.4. Decreto número 2358 de 2019 35-- 5. Metodología 37-- 6. Resultados 45--
6.1. Procesos históricos que acontecieron a lo largo del crecimiento de la ciudad de Barranquilla 45-- 6.2. Noción del patrimonio desde la perspectiva del ciudadano 69--
6.2. La influencia del patrimonio en el entorno actual 77-- 6.2.1. ¿Cómo actúan las intervenciones de las entidades públicas? 77-- 6.2.2. ¿Cómo toman acción las entidades en las diferentes intervenciones realizadas? 78-- 6.2.3. Relación de estudio técnico hacia edificaciones patrimoniales del centro histórico de Barranquilla 79-- 6.3. Conservación del patrimonio a través del tiempo en espacio público - sector C.h de Barranquilla. 88-- 6.4. Estrategias apoyadas en base al plan de desarrollo de Barranquilla para la mitigación del deterioro patrimonial 118-- 7. Conclusiones 122-- 8. Referencias 124--Arquitecto(a)Pregrad
Phenomenology as a scientific research method: a systematic review
No full textEl artículo analiza la fenomenología como corriente filosófica y como método de investigación científica. Para lograr tal fin, se realiza un recorrido por su fundación, considerando los principales preceptos de sus precursores, tales como Edmund Husserl y Martin Heidegger, acerca de la manera de comprenderse y percibirse los fenómenos. Al mismo tiempo, se presenta un análisis de contenido mediado por la revisión sistemática de las investigaciones que se han realizado en el último año a través del empleo de la fenomenología como problema o método de investigación, tomando en cuenta las principales disciplinas, áreas temáticas y aportes que se han hecho a la investigación científica.The article analyzes phenomenology as a philosophical current and as a method of scientific research. To achieve this end, a tour of its foundation is carried out, considering the main precepts of its precursors, stories such as Edmund Husserl and Martin Heidegger, about the way of understanding and perceiving phenomena. At the same time, a content analysis is presented mediated by the systematic review of the research that has been carried out in the last year through the use of phenomenology as a research method, taking into account the main disciplines, thematic areas and contributions that have been made to scientific research
Análisis de costos de la atención de enfermedades mentales en la población afiliada a una aseguradora en salud en el departamento del Atlántico (Colombia), 2020-2021
No full textAntecedentes. El 40,1% de la población en Colombia entre 18 y 65 años ha sufrido alguna vez de un trastorno mental y 1 de cada 10, con edades de 18 a 44 y 12 de cada 100 adolescentes tienen algún problema que sugiere la presencia de una enfermedad mental. Los costos de atención de esta población ascendieron a 9.092 millones, para un promedio mes de 371 mil por afiliado, 1,2 millones por mujer y 11.452 billion in 2017. There has been no analysis of these costs in Colombia, the Caribbean region or the department of Atlántico. Objective. To analyze the costs related to the care of mental health problems in health insurer in its Atlántico region. Population. 293,472 affiliates of a health insurer in its Atlántico region, of which 3,867 were treated for mental health disorders. Methods. Information was collected on the care provided to the defined population between January 1, 2020, and October 31, 2021. Data analysis was performed in Microsoft Excel®. Main outcome measures. Total costs of care and annual and monthly average, discriminated by sex, diagnostic group and scope of care. Results. Total costs of care were 413 million. The 70.58% were for elective outpatient services. The age group that accumulated the highest cost was between 19 and 44 years of age (36.7%). The distribution by sex was similar. The cost per year was 1.2 million per user, 1.4 million per man. Conclusions. It was found that the costs of metal health care are mainly for outpatient and urgent hospital services, and that they only cover a part of the identified population.Lista de tablas y figuras 8 -- Resumen 10 -- Abstract 11 -- Introducción 12 -- Planteamiento del problema 15 -- Descripción del problema 15 -- Formulación del problema 17 -- Justificación 17 -- Objetivos 19 -- Objetivo general 19 -- Objetivos específicos 19 -- Marco Legal 19 -- Marco teórico 20 -- Carga de enfermedad 20 -- Relación existente entre las enfermedades mentales y las físicas 21 -- Costos de la salud mental 22 -- Estado del arte 25 -- Marco contextual 26 -- Metodología 28 -- Tipo y enfoque de investigación 28 -- Población y muestra 28 -- Técnicas de recolección y análisis de información 28 -- Operacionalización de las variables 29 -- Consideraciones éticas 29 -- Resultados 30 -- Caracterización de la población con problemas de salud mental afiliada a la Aseguradora de Salud 30 -- Costos relacionados con la atención ambulatoria y hospitalaria de los problemas de salud mental de la población afiliada 32 -- Análisis de los costos incurridos en la atención de las alteraciones de la salud mental en la población afiliada 39 -- Discusión 42 -- Conclusiones 44 -- Referencias 45Magíster en Gestión de Servicios de SaludMaestrí