bluuebunny/crossref_metadata_2025 huggingface dataset:
Conocimientos y prácticas en salud sexual de los estudiantes de la Universidad de Antioquia, Medellín, Colombia, 2014
Authors: Álvarez Osorio Liliana Patrícia , Tamayo Acevedo Lucia Stella , Moreno Ruíz Mónica Andrea
Published: January 2023

Introducción: La sexualidad es inherente la humanidad; su vivencia acompaña la cotidianidad y tiene efectos sobre la salud sexual. La educación sexual se realiza durante las etapas de la vida, incluyendo la universitaria. Objetivo: determinar el nivel de conocimientos y prácticas en salud sexual de estudiantes de pregrado de la Universidad de Antioquia.

Resultados: Se encontró alta frecuencia de prácticas de riesgo: 79,8% no usó o recurría irregularmente al condón, el 52,5% no utilizó condón en la última relación sexual, el 23,6% sostenía relaciones sexuales con personas diferentes a la pareja y el 21,8% tuvo más de tres parejas en el último año; con marcada diferencia de género. En la valoración de conocimiento primaron los niveles aceptable y deficiente, principalmente en hombres, estudiantes de las regiones y de las áreas de ciencias sociales, ingeniería y ciencias exactas y naturales, y en adolescentes.

Conclusiones: Este estudio encontró alta frecuencia en las prácticas de riesgo para la salud sexual y deficientes conocimientos en este mismo campo. Se resaltan las diferencias encontradas en el comportamiento de las prácticas de riesgo entre hombres y mujeres, así como para el nivel de conocimientos; situaciones a considerar en la reorientación de los programas de educación sexual.
Etiología infecciosa del flujo vaginal en mujeres atendidas en el Laboratorio Clínico VID de Medellín
Authors: Estrada Santiago , Vanegas Claudia , Yepes Sandra Milena , Ortiz Victor , Ruiz Kelly , Gutiérrez Gladys , Arango Valeria , Jaramillo Laura , García Verónica
Published: January 2023

Objetivo: Conocer la etiología infecciosa del flujo vaginal, de mujeres atendidas en el Laboratorio Clínico VID (LCVID).

Materiales y métodos: Se trata de un estudio descriptivo retrospectivo, donde se consultó la base de datos del (LCVID), en el periodo comprendido entre enero de 2.014 a diciembre de 2.015, para determinar que agentes infecciosos se identificaron en las mujeres que asistieron al examen directo y Gram de flujo vaginal. Para este estudio el Laboratorio cuenta con un protocolo estandarizado que permite establecer el objetivo planteado.

Resultados: Se analizaron 4.738 registros de las mujeres que se atendieron en el período establecido. Una vez seleccionados los registros, se agruparon por rangos de edad para las entidades que se estudian en nuestro protocolo: mujeres de 16 a 25 años, de 26 a 35, de 36 a 45 de 46 a 55 y mayores de 56 años. Del total de muestras procesadas en 39 (0,83%) se diagnosticó tricomoniasis vaginal (TV), en 2.009 (42,4%) Candidiasis vulvovaginal (CVV), en 1.343 (28,3%) Vaginosis bacteriana (VB) y en 1.357 (28,4%) no se encontró etiología infecciosa.

Conclusiones: No obstante se trata de un estudio descriptivo retrospectivo; el tamaño de la muestra lo presenta como un estudio robusto para el análisis. Es de resaltar que Trichomonas vaginalis no fue un agente importante, diferente a Candida spp. que ocupó el primer lugar, seguido de Vaginosis bacteriana.
Aspectos clínicos y epidemiológicos de la infección por virus Zika: implicaciones de la actual epidemia en Colombia y América Latina
Authors: Rodríguez Morales Alfonso J. , Acevedo Wilmer F. , Villamil Gómez Wilmer E. , Escalera Antezana Juan Pablo
Published: January 2023

El Virus Zika (ZIKV) es un arbovirus del género de los Flavivirus en la familia Flaviviridae. A este grupo pertenecen otros de importancia clínica como son el virus del dengue (DENV), virus de la fiebre amarilla (YFV) y el virus del Nilo occidental (WNV). El ZIKV fue identificado por primera vez en monos Rhesus del bosque Zika, en Uganda, del cual recibió su nombre (1947) y posteriormente fue aislado en seres humanos en Nigeria (1954). La presentación clásica de la enfermedad consiste en síndrome febril leve, poliartralgias levas a moderadas, rash maculopapular, con o sin mialgias, y con o sin cefalea. Se ha asociado al desarrollo de alteraciones neurológicas y posiblemente malformaciones congénitas en la gestación. Los mosquitos Aedes aegypti son el vector principal pero otras especies y géneros podrían estar involucrados. El ZIKV fue una enfermedad desatendida por su limitado número de casos y bajo impacto clínico en comparación con otros arbovirus. Para 2016, la Organización Mundial de la Salud declaró al ZIKV como una emergencia de salud pública de importancia internacional. Su trasmisión autóctona ha sido reportada en muchos países.
Blastocystis spp. En pacientes ingresados en salas de medicina interna del hospital “Joaquín Albarrán” de la Habana, Cuba, julio 2011-junio 2012
Authors: Batista Kushinski Osmar
Published: January 2023

Introducción: Blastocystis spp. es un parásito que generalmente se asocia con enfermedad diarreica. El objetivo de este estudio fue caracterizar clínicamente los pacientes con infección por Blastocystis spp. que fueron atendidos en las salas de medicina interna del hospital “Joaquín Albarrán” en la Habana, Cuba entre 2011-2012.

Métodos: se realizó un estudio descriptivo de corte transversal, donde se identificaron los casos positivos de Blastocystis spp., en el examen de heces de los pacientes ingresados en las Salas de Medicina del Hospital Clínico Quirúrgico Joaquín Albarrán, durante el periodo comprendido entre julio de 2011 y junio de 2012.

Resultados: se encontró que la frecuencia de enfermedad diarreica fue de 13,3 por cada 1000 ingresos en el servicio de medicina. En el 52,4 % de los pacientes ingresados por enfermedad diarreica estuvo presente Blastocystis spp. en el análisis microbiológico de las heces. Adicionalmente, las enfermedades asociadas a los casos positivos de Blastocystis spp., en orden de frecuencia fueron: anemia, hipertensión arterial, diabetes mellitus tipo 2, cardiopatía isquémica y hepatopatía crónica. Se utilizó tratamiento antibiótico en el 58 % de los pacientes infectados Blastocystis, y se obtuvo una resolución del cuadro diarreico en un 86,1 % de los casos donde se administró tratamiento.

Conclusiones: los resultados de este estudio sugieren la probabilidad de que la enfermedad diarreica pueda ser causada por B. hominis, y por lo tanto este debe considerarse en el algoritmo diagnóstico de esta patología.
Especies de Anopheles (Diptera: Culicidae) detectadas en estado larval en localidades endémicas para malaria del occidente y noroccidente Colombiano
Authors: Quintero Juan José , Altamiranda Saavedra Mariano , Correa O. Margarita M.
Published: January 2023

Introducción: Los  hábitats  larvales  son  determi-nantes importantes de la presencia de las especies de Anopheles.El objetivo de este estudio fue evaluar las especies anofelinas detectadas en estado larval en zo-nas endémicas de malaria del occidente y norocciden-te de Colombia.

Materiales y Métodos: Se colectaronlarvas de Ano-pheles en localidades endémicas para malaria. Para los hábitats larvales positivos se registró la vegetación que rodea a los hábitats y la sombra. Se correlacionaron la temperatura del agua del hábitat, su pH y distancia a la casa más cercana, con la abundancia de las especies detectadas.

Resultados: Las especies encontradas en  estado  larval  en  mayor  abundancia  correspondieron  a  los  vectores principales de Colombia, Anopheles nuneztova-ri,An.  darlingi  y  An.  albimanus  y  en  baja  abundancia,  la especie An. malefactor. Los tipos de hábitat larvales positivos variaron y los más representativos fueron, lagos,  jagüeyes,  humedales,  lagunas  y  estanques.  Se  encontró correlación significativa entre presencia de larvas  de  An.  nuneztovari  con  el  pH  y  la  temperatura  del agua.

Conclusión: Este estudio aporta información re-levante sobre algunos parámetros ambientales y eco-lógicos  que  pueden  determinar  la  presencia  de  espe-cies  en  estado  larvario  de  importancia  vectorial,  esta  información podría constituir la base para el diseño y  aplicación  de  intervenciones  de  control  vectorial  especie-específicos.
Bacteriófagos: aspectos generales y aplicaciones clínicas
Authors: Castaño Osorio Jhon Carlos
Published: January 2023

En este artículo se recopila la información publicada disponible respecto a la terapia con bacteriófagos, para así brindar al lector un documento de referencia en español para su consulta el cual incluye la definición, estructura morfológica, ciclo de vida de estos organismos, historia, alternativa a la antibiótico-resistencia, clasificación de los fagos, mecanismos de acción, implicaciones terapéuticas, ventajas y desventajas de esta terapia, así como el estado actual de la terapia con fagos. También se describen algunos ejemplos de utilización de fagos como en el control biológico de plagas en plantas e infecciones en animales, así como otras áreas de uso de los bacteriófagos, y se revisan los mecanismos de resistencia a los fagos, además del futuro de la terapia con bacteriófagos y termina con unas reflexiones finales de la fago terapia.
Papel de los hongos formadores de micorrizas en la biorremediación de suelos agrícolas contaminados con metales pesados: revisión sistemática
Authors: Cano Tamayo Alicia Isabel , Zuleta Zapata Diana Milena , Ríos Osorio Leonardo Alberto
Published: January 2023

Introducción: el objetivo de esta investigación fue describir el papel de los hongos micorrízicos en los procesos de biorremediación de suelos contaminados con metales pesados a partir de una revisión sistemá-tica de la literatura científica.

Métodos: se  realizó  una  revisión  sistemática  de  la literatura científica publicada entre 2003 y 2014 en  las  bases  de  datos  ScienceDirect,  Springer  Link  y  EBSCO. Esta búsqueda produjo un total de 39 artí-culos originales, filtrados por criterios de inclusión y exclusión. Adicionalmente, se incluyó literatura com-plementaria obtenida mediante la herramienta de bús-queda Google Academic.

Resultados y conclusión: este estudio reveló que las endomicorrizas y las ectomicorrizas son los tipos de micorrizas  más  frecuentemente  descritos  en  suelos  contaminados por metales pesados y que tienen me-canismos  de  tolerancia  al  estrés  generado  por  estos  elementos, los que incluyen la absorción y absorción de metales pesados, la promoción del crecimiento de las plantas, la alteración de propiedades bioquímicas y fisiológicas de la planta y producción de metabolitos.
Parasitosis Intestinales y su relación con factores higiénicos y sanitarios en habitantes de las veredas Río abajo, Los Pinos, Rionegro, Antioquia, 2008
Authors: Hernández Rendón Sebastián , Chaurra Silva Mauricio , Montoya Giraldo Juan D. , Urrego Álvarez Ana M. , Ríos Osorio Leonardo A.
Published: January 2023

Introducción En todo el mundo, el 80% de las enfermedades infecciosas parasitarias gastrointestinales y una tercera parte de las defunciones causadas por estas, se deben al uso y consumo de agua insalubre. La falta de higiene y carencia, o mal funcionamiento, de los servicios sanitarios son algunas de las razones por las cuales la diarrea continúa representando un importante problema de salud pública en países en desarrollo. Objetivo Relacionar la presencia de parasitosis intestinales en los habitantes de las veredas Río abajo, Los Pinos con factores higiénicos y sanitarios. Materiales y métodos Estudio descriptivo de corte transversal realizado con población de la vereda Río Abajo, Los Pinos. A todos los individuos se les realizó examen coprológico por lectura directa en fresco y lugol, y por concentración con la técnica de formol-éter en el Laboratorio de Parasitología, Facultad de Medicina, Universidad de Antioquia. Resultados La frecuencia de infección por parásitos intestinales fue 74,4% en la vereda Río Abajo y 78,6% en Los Pinos. Se obtuvo relación significativa por χ2 entre parasitosis intestinales y lavado de manos para el consumo (p <0,013), almacenamiento de basuras (p<0,001) y dolor abdominal (p<0,0345). La presencia de Blastocystis spp. fue significativa y se relacionó con vómito (p<0,0138), náusea (p<0,0061), dolor de estómago (p<0,0313), almacenamiento de basuras (p<0,0005) y conexiónde agua (p<0,0219). Conclusión Se evidencia la necesidad de realizar estudios sobre patogenicidad de Blastocystis spp., al igual que el reconocimiento y discriminación de especies circulantes para poder diferenciar su grado de virulencia.
Perfil hematológico de los trabajadores de la minería del oro expuestos a vapores de mercurio metálico en el municipio de Amalfi, Antioquia
Authors: Acevedo Toro Paola A. , Guevara Arismendy Natalia M. , Rodríguez Acevedo Adriana M.
Published: January 2023

Objetivo
Determinar el perfil hematológico de los trabajadores de la minería del oro expuestos crónicamente a los vapores de mercurio metálico en Amalfi, Antioquia.
Materiales y Métodos
Se incluyeron 41 mineros y siete trabajadores de la compraventa del oro expuestos a los vapores de mercurio metálico (pareados con 48 controles). A cada participante se le realizó hemoleucograma, extendido de sangre periférica y determinación de mercurio en orina de 24 horas.
Resultados
Los trabajadores de la minería del oro tuvieron una concentración promedio de mercurio en orina de 59,7 μg/L y se observaron múltiples alteraciones cualitativas y cuantitativas en el hemoleucograma, de las cuales los valores de hemoglobina, hemoglobina corpuscular media (HCM) y la concentración de hemoglobina corpuscular media (CHCM) presentaron una diferencia estadísticamente significativa entre el grupo de expuestos y el grupo control (p<0,05).
Conclusión
Existe una posible relación entre la exposición a los vapores de mercurio metálico y el recuento diferencial de leucocitos, hemoglobina y constantes corpusculares; sin embargo, se requieren estudios adicionales para confirmar el efecto de este metal sobre la homeostasis hematopoyética.
Caracterización biológica de dos aislados de Leptospira spp. procedentes de pacientes colombianos con síndrome de Weil
Authors: Durango-Galván Harold E. , Rodas-González Juan D. , Travi Bruno L. , Agudelo-Flórez Piedad
Published: January 2023

Se describe la dinámica de la infección experimental en el modelo hámster de dos aislados de Leptospira spp. recuperados de pacientes con síndrome de Weil, procedentes de poblaciones Antioqueñas. La infección experimental se realizó mediante inoculación intraperitoneal de los aislados en hámsteres juveniles. La evaluación de marcadores de función hepática y renal, además de un reactante de fase aguda de inflamación, se realizó en dos momentos postinfección. A los 18 días postinoculación se establece el punto final, colectando sangre y realizando la necropsia, tomando tejido de hígado, riñón y pulmón, para cultivo en EMJH y en formol tamponado para estudio histopatológico. Los resultados de las pruebas de función renal, hepática y la proteína C reactiva fueron variables, y aunque mostraron ligeros aumentos no se correlacionó con la presencia de signos clínicos; sin embargo, en la histopatología se tiene la expectativa de evidenciar algún cambio importante, ya que se obtuvo crecimiento bacteriano a partir del cultivo de riñón e hígado en algunos de los animales. Los resultados de la evaluación de la virulencia a través de la determinación de la dosis letal 50 sugiere que los dos aislados eran poco virulentos o habían perdido virulencia quizás debido a los pases sucesivos in vitro a que se sometieron antes de inocularlos en los animales.
Pruebas bioquímicas para la detección de metabolitos producidos en los Errores Innatos del Metabolismo
Authors: Mesa Herrera Natalia Regina , Carmona Carmona Cristian Andrés , Burgos Herrera Luis Carlos
Published: January 2023

Los errores innatos del metabolismo (EIM) son más de 550 enfermedades en las que se presenta una deficiencia o ausencia de proteínas con actividad enzimática, transportadora, receptora o estructural. Cada una de estas enfermedades es rara, pero su gran variedad hace que, consideradas en conjunto, sean la principal patología neonatal. Para la detección de los metabolitos producidos en los EIM se pueden utilizar pruebas cualitativas. Su utilidad radica en que son muy rápidas y de fácil acceso, y en que sirven como pruebas presuntivas para proceder a hacer exámenes más especializados o para enfocar el diagnóstico. Teniendo en cuenta su importancia para un diagnóstico temprano de los EIM, el objetivo del presente artículo es describir el funcionamiento de las pruebas bioquímicas de resorcinol, dinitrofenilhidrazina, nitrosonaftol, nitroprusiato y Hoesch, haciendo énfasis en los metabolitos que detectan.
Paciente con malformación cardíaca congénita y endocarditis infecciosa
Authors: Ramírez Ortiz Zoraida , Arias Luis Fernando , Cataño Correa Juan Carlos
Published: January 2023

Se presenta el caso de un hombre de 17 años, sin antecedentes de importancia, quien consultó por un mes de evolución de deterioro de su clase funcional, fatigabilidad y disnea, además de fiebre y síndrome de respuesta inflamatoria sistémica (SIRS) en quien se documentaron una malformación congénita de novo tipo situs inversus con levocardia y una comunicación interventricular (CIV), asociadas a transposición de grandes vasos; durante la hospitalización recibió varios tratamientos con antibióticos sin aislamiento microbiológico ni identificación de la causa de su descompensación hemodinámica. En el examen post-mortem se identificó endocarditis por Aspergillus spp., con embolia a diferentes órganos.
Hipertensión pulmonar severa asociada a enfermedad de Takayasu
Authors: Arevalo Guerrero Edwin , Sénior Juan Manuel
Published: January 2023

Se presenta el caso de una mujer de 57 años de edad, con antecedente de hipertensión arterial crónica, y cuadro de 2 años de evolución de disnea, síntomas generales, malestar, fatigabilidad e intolerancia al ejercicio, deterioro de su capacidad funcional y episodios ocasionales de presíncope. Al examen físico se le encontraron cifras tensionales elevadas, con diferencia de más de 10 mm Hg entre las presiones del miembro superior derecho y las del izquierdo, soplo holosistólico grado III/VI en los focos de la base, soplo subclavio izquierdo y disminución de la intensidad de los pulsos periféricos del miembro superior izquierdo. Los síntomas la obligaron a consultar en varias oportunidades a instituciones de salud de la ciudad, donde le hicieron estudios que mostraron hipertensión pulmonar severa y disfunción ventricular derecha, confirmadas por cateterismo cardíaco. Se le hicieron angiotomografía de tórax y angiografía arterial pulmonar que fue sugestiva de estenosis arterial pulmonar bilateral. En la resonancia magnética cardíaca se hallaron estenosis (6 mm) concéntrica que comprometía el origen de la rama para el lóbulo superior y afectación circunferencial de la rama izquierda (8 mm) y de la rama para el lóbulo inferior. En la aorta y los vasos del cuello se observaron irregularidades endoluminales tanto en la resonancia como en la angiotomografía. Con estos hallazgos se hicieron los diagnósticos de arteritis de Takayasu e hipertensión pulmonar severa asociada y se inició tratamiento con prednisolona y metotrexate.
Factores endógenos de la fragilidad financiera en unidades económicas colombianas. Aplicación de un modelo de análisis discriminante.
Authors: Rahmer Bruno de Jesus
Published: January 2023

Las investigaciones que versan sobre finanzas corporativas se han focalizado tradicionalmente en el estudio de decisiones financieras a corto y largo plazo, en particular, aquellas que atingen a las modificaciones en la estructura de capital, evaluación de fuentes de financiamiento y estrategias de maximización de valor, entre otras. Se colige a partir de aquí, que los procesos de gestión financiera forman una parte fundamental de la estrategia corporativa. El objetivo ulterior de este paper es analizar el desempeño financiero de 150 empresas del sector manufacturero y metalmecánico colombiano durante el periodo referencial 2019-2020. Para tal efecto, se estima un modelo de análisis discriminante de Fisher en procura de encontrar una combinación lineal de variables de orden económico, financiero y operativo y segmentar a las unidades estratégicas de negocios. Este set de parámetros proporciona información sobre las fuentes y detonadores de la inestabilidad, causada por dinámicas internas del sector en que se hayan circunscriptas las empresas. Los resultados indican que la fragilidad de las firmas surge como consecuencia de descoordinaciones en la política gestión de capital de trabajo. Así, por ejemplo, aquellas entidades que han adoptado esquemas especulativos y tipo Ponzi, exhiben peores indicadores de productividad, endeudamiento y de gestión de cartera, respecto a sus contrapartes con esquemas de financiación cubiertos.
Blood Cell Tracing in a Microchannel by Using Dielectrophoresis Force
Authors:   Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, Bangi UKM, Selangor, Malaysia, Ali Othman Nur Tantiyani , Abul Kalam Farah Syafiqah ,   Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, Bangi UKM, Selangor, Malaysia
Published: February 2023

The conventional techniques of platelet separation are by using a centrifugation and acoustic. However, by using these techniques, the platelets become active due to the relatively high-speed centrifugal force and large amount of a sample usage. Therefore, to overcome this problem, an electric separation technique is preferred as it relies more on the dielectric properties of particles, that allow for highly selective and sensitive analysis. One of them is dielectrophoresis (DEP), which is the force resulting from an interaction between bipolar particles in a non-uniform electric field that can be used to separate neutral particles. The DEP force allows the separation of platelets from red blood cells due to dielectric properties of the particles and medium as it requires small quantities of samples, lower reagents usage, and low-cost equipment. In this study, H-type microchannel with two inlets and outlets was developed by using COMSOL© software to observe the cell distribution at blood concentrations; CA=0.01, 0.015, 0.02, 0.025 and 0.03 mol/m3, with feed velocities at the inlet B; vB=600, 700, 800, 900 and 1000 μm/s and at voltages charged; V=-30V to 30V that applied at the five electrodes. The simulation results show the optimization of blood cell concentration and velocity were achieved at the outlets at CA=0.01 mol/m3 and vB=800 μm/s, respectively. Moreover, the optimum voltage for platelet cell separation was at V=10V as it shows the highest DEP force; FDEP=-3.19×1013 N/m as compared to the other tested voltages.
Three-Axes Rotation Algorithm for the Relaxed 3L-CVRP
Authors:   Systems and Computation Instituto Tecnologico de Puebla, Puebla, Mexico, Rojas-Cuevas Irma-Delia , Caballero-Morales Santiago-Omar ,   Department of Logistic and Supply Chain Management, Universidad Popular Autonoma del Estado de Puebla A.C., Puebla, Mexico, Sánchez-Partida Diana ,   Department of Logistic and Supply Chain Management, Universidad Popular Autonoma del Estado de Puebla A.C., Puebla, Mexico, Martínez-Flores José-Luis ,   Department of Logistic and Supply Chain Management, Universidad Popular Autonoma del Estado de Puebla A.C., Puebla, Mexico
Published: February 2023

The purpose of this work is to present a developed three-axes rotation algorithm to improve the solving methodology for the relaxed 3L-CVRP (Three-Dimensional Capacitated Vehicle Routing Problem). Although there are reported works on solving approaches for the relaxed 3L-CVRP that consider product rotation to optimize load capacity, rotation on the three axes has not been thoroughly studied. In this aspect, the present work explicitly explores the three-axes rotation and its impact on load capacity optimization. In order to improve the relaxed 3L-CVRP problem, a two-phase solution was developed. The first phase consists of finding the solution for the CVRP problem, using a demand previously obtained with a heuristic developed to convert the 3L-CVRP demand into CVRP demand. The second phase is to obtain the loading of the vehicle using a heuristic developed to load the items using rules to obtain the rotation of the items. The proposed approach was able to improve the load assignment in 48.1% of well-known 3L-CVRP instances when compared to similar approaches on the relaxed 3L-CVRP. The outcomes of this research can be applied to transportation problems where package rotation on the z-axis is an option, and there are not fragile items to load in the vehicles.
Epoxy/Copper Oxide Composite Coating for Marine Application
Authors:   Department of Chemical & Process Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Malaysia, Tabri Kautsar , Yuhana Nor Yuliana ,   Department of Chemical & Process Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Malaysia, Jaafar Jafreena Adira ,   Research Centre for Sustainable Process Technology (CESPRO), Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Malaysia, Al Shafiei Ahmad Faiz ,   Bina Integrated Industries Sdn. Bhd., No. 10 Jalang/7, Taman lKS, Seksyen 9, 43650 Bandar Baru Bangi, Selangor, Malaysia, Mohd Suhil Mohammad Aslamilie ,   Bina Integrated Industries Sdn. Bhd., No. 10 Jalang/7, Taman lKS, Seksyen 9, 43650 Bandar Baru Bangi, Selangor, Malaysia
Published: February 2023

This research investigated the usage of cuprous oxide powder as filler for epoxy in marine coating industries. The basic formulation consist of cuprous oxide powder, epoxy pre-polymer, and the curing agent. The main manipulation variable in this research is the quantity of cuprous oxide added into the epoxy resin, which varies from 2, 5, 7, 9, and 11 per hundred gram of epoxy resin (phr). Polyether (amine) was used as the curing agent at equivalent molar ratio. Mechanical stirring was used to achieve dispersion. The samples were cured at room temperature for one week before characterization. Differential scanning calorimetry (DSC), scanning electron microscopy (SEM), infrared spectroscopy (FTIR), X-ray diffraction (XRD), drop shape, water and brine absorption, hardness, and abrasion analysis were used. Drop shape analysis exhibited the hydrophobicity of the surfaces. According to water and brine absorption test that was carried out, it is found that the unmodified epoxy sample has the lowest absorption of water and brine. The composite coating, which underwent abrasion test, exhibited increasing hydrophobicity of the surface directed on the electrical wave generator in 5 days.
Absorption of Electromagnetic Radiation on Human Lower Back Region
Authors:   Department of Physical Medicine & Rehabilitation, Bangabandhu Sheikh Mujib Medical University, Dhaka 1000, Bangladesh, Shakoor M. A. , Moyeenuzzaman M. ,   Department of Physical Medicine & Rehabilitation, Bangabandhu Sheikh Mujib Medical University, Dhaka 1000, Bangladesh., Azim R. ,   Department of Physics, University of Chittagong, Chittagong 4331, Bangladesh, Chakraborty S. R. ,   Department of Physics, University of Chittagong, Chittagong 4331, Bangladesh, Islam M. T. ,   Department of Electrical, Electronic and System Engineering, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia, Samsuzzaman M. ,   Department of Computer and Communication Engineering, Patuakhali Science and Technology University, Patuakhali 8602, Bangladesh
Published: February 2023

In this paper a simulation study is conducted on lower back region of human phantom to observe the absorption of electromagnetic (EM) radiation. To investigate the effectiveness, EM radiation with different frequencies (1-100 GHz) is administrated step by step in different tissue thickness (up to 25 mm) of lower back region of human phantom and using EM simulator HFSS, return loss (RL) is recorded at every stage. From the results, it is found that when radiation with frequency 0.899 GHz to 1. 089 GHz (~1 GHz) is applied return loss is varies from 0.413 dB to 1.022 dB in different thicknesses. This indicates that only 1.1 % of the incident power is absorbed maximally. When radiation of 9.899 GHz to 10.099 GHz (~10 GHz) frequency is applied, the return loss value obtained is 6.731 dB to 6.280 dB for different tissue thicknesses. This indicates that only 10.1 % power is absorbed maximally. Finally, when radiation with frequency 99.899 GHz to 100.1 GHz (~ 0.1 THz) is applied, the return loss value is found ranging from 26.902 dB to 26.429 dB in different thicknesses which indicates that almost 99.9% of the incident radiation is absorbed by the human tissue i.e. almost 100% of the incident radiation is absorbed in human lower back region in THz range. From therapeutic point of view, almost the entire incident radiation is attenuated to the lower back region with THz radiation which is clinically very useful in treating chronic low back pain.
Structural Performance of One-Way Slabs Reinforced with Steel and Polypropylene Fibers
Authors:   Department of Civil Engineering, University of Engineering and Technology, Taxila, 47080, Pakistan, Zaman Khan Qaiser uz , Ahmad Afaq ,   Department of Civil Engineering, University of Engineering and Technology, Taxila, 47080, Pakistan, Raza Ali ,   Department of Civil Engineering, Pakistan Institute of Engineering and Technology, Multan, 66000, Pakistan, Labibzadeh Mojtaba ,   Department of Civil Engineering, Faculty of Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran, Iqbal Muhammad ,   Creative Engineering & Management Solutions, Deans Centre Peshawar, 25000, Pakistan
Published: February 2023

The present study aims to investigate the effects of the steel fibers (SF) and polypropylene fibers (PPF) on the structural response of one-way simply supported reinforced concrete (RC) slabs at the ultimate limit state (ULS). Next, an optimized combination of the hybrid fibers is proposed. The experimental program includes 21 experiments on the one-way slabs with different SF and PPF ratios. The load-deflection curves were obtained for slabs using a four-point bending method. The ultimate capacity and mid-span deflection of the slabs were measured. The experimental results did not produce a consistent trend of ultimate loading. The different blends produced different failure modes, cracking load, and ultimate failure load. Based on the obtained test results, the slab specimen, SM6, with 0.7% SF and 0.9% PPF ratios has the maximum and the slab specimen, SM16, with 0.9% SF and 0.9% PPF ratios has the minimum load-carrying capacity, respectively. The first shows a 31% increase and the second indicates a 31% reduction when compared to the reference slab specimen, SM1, which has no fibers used in its concrete mixture. It is worth to mention that the slab specimen, SM6, which has the largest load-carrying capacity, also shows the highest ductility (172% enlargement in deflection when compared to the reference slab, SM1).
Forced Convective Heat Transfer Analysis for Two-dimensional Slot Jet of Water-CuO Nanofluid
Authors:   Department of Mechanical Engineering, Memorial University of Newfoundland (MUN) St. John’s, A1A 3X5, NL, Canada, Etminan Amin , Harun Zambri ,   Department of Mechanical and Manufacturing Engineering, Faculty of Engineering and Built Environment Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia
Published: February 2023

This paper investigates the effect of the diameter and the volume fraction variation of the centre nanoparticles on the heat transfer characteristics of a two-dimensional slot jet. The jet impinges on stationary flat, convex, and concave aluminium plates. A forced convective heat transfer coefficient of water-CuO nanofluid impinges on a smooth plate under a constant heat flux. The finite volume method (FVM) is implemented for nanoparticles with diameters varying from 7 to 60 nanometers, volume fractions changing from 0 to 5%, and the Reynolds numbers ranging from 1800 to 2800. A grid independence study is carried out to find a grid size that predicts the results accurately and further grid refinement changes the results insignificantly. The single-phase model shows a capability to predicts the fluid and heat transfer parameters faster and make it more suitable for numerical simulations compared to the two-phase model. The results indicate a higher heat transfer coefficient of nanofluid in comparison with distilled water. As the Reynolds number and nanoparticle volume concentrations increase, the heat transfer rate increases on the surface whilst smaller nanoparticle diameters increase during the cooling process. The increase in the diameter of nanoparticles enhances the Nusselt number on the plate by up to 10%. The same geometrical details, thermophysical, and boundary conditions have been employed in all calculations for distilled water jet simulations to validate the fluid flow behaviour and heat transfer parameters with available experimental data in the literature.
Simulation Study on the Effect of Dielectrophoresis Force on a Separation of Platelet from Blood Cell in a 3D Mini Channel
Authors:   Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, Bangi UKM, Selangor, Malaysia, Ali Othman Nur Tantiyani , Lee C. S. ,   Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, Bangi UKM, Selangor, Malaysia
Published: February 2023

In recent years, separation of platelet from a blood cell received growing attention due to its usages for blood disorders or any disease treatment. However, the conventional separation techniques have some constraint due to its limitation to separate the cells with similar properties, costly, requires longer processing time, and less data accuracy. Thus, under the effect of a uniform electric field, a dielectrophoretic (DEP) force was applied as its ability to separate on a similar diameter size of cells, has lower cost, and requires only a small volume of sample. In this study, a 3D mini channel model with a Y-shape was developed using AutoCAD® and the velocity profile distribution was observed using ANSYS© Fluent version 19.1. Three parameters were observed at various an electric field intensity; E=±1 to ±5 V/mm, an electric field frequency, f=1 kHz to 1 MHz and a particle diameter; d=1.3 to 2.0μm. The results show the velocity was increased as the higher of electric field intensity and larger particle diameter. Besides, the DEP force was increased as the higher electric field intensity was charged for all tested frequencies. As well, as the higher the electric field intensity charged and the larger the particle diameter, the stronger of the DEP force. It can be concluded that the DEP force at d=2.0μm and E=5 V/mm was the optimum conditions and obtained the highest result among all the tested parameters. Under these optimum conditions, it shows the DEP force can separate the platelet from the blood cells.
Numerical Evaluation of Structural Concrete Insulated Panels for Thermal Energy Efficient Buildings
Authors:   Department of Civil Engineering, Mirpur University of Science and Technology (MUST), Mirpur-10250, AJ&K, Pakistan, Ahmed Sohaib , Khitab Anwar ,   Department of Civil Engineering, Mirpur University of Science and Technology (MUST), Mirpur-10250, AJ&K, Pakistan
Published: February 2023

This study is focused on thermal evaluation of Structural Concrete Insulation Panels (SCIPs) as building material. In Pakistan energy shortage is one of major issues since the last decade. As buildings consume more than 40 % of total production of electrical energy, it is necessary to innovate, analyse and apply various energy saving and optimization techniques for constructing thermal energy efficient buildings. SCIPs consist of three layers, in which a central polystyrene foam is sandwiched between two concrete layers. SCIPs are available in flexible sizes ranging from 0.3-1.2 m in width and 2.4-3.0 m in length. Owing to their light weight and easy fabrication, they are suitable for remote areas and severe weather conditions. In this study, numerical approach is used to compare the thermal performances of SCIPs and ordinary concrete incorporated walls in a school building system. Hourly recorded data of dry-bulb and dew-point temperatures of surface, humidity and mean air temperatures are used in simulation. Data for one typical year are used to compare the energy requirements of building made of ordinary concrete and SCIPs walls with expanded polystyrene as insulation material. Simulation results were acquired by means of EnergyPlus software and are presented to evaluate the heating and cooling demands of energy for a year. Study reveals that the SCIP walls incorporated buildings have a greater energy efficiency, reduce energy demand by 25% and HVAC systems by 20 % for assigned thermal zone.
Computer Aided Simulation POME Biogas Purification System
Authors:   Milling and Processing Unit, Engineering & Processing Division, Malaysian Palm Oil Board (MPOB) No.6 Persiaran Institusi Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia, Chung Andrew Yap Kian , Hasanah M.N Ummi Kalsum ,   Milling and Processing Unit, Engineering & Processing Division, Malaysian Palm Oil Board (MPOB) No.6 Persiaran Institusi Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia
Published: February 2023

About three (3) tonnes of palm oil mill effluent (POME) is generated when one (1) tonne of crude palm oil (CPO) is produced. Microbial digestion treatment is commonly used in Malaysian palm oil mills due to the low capital expenditure (CAPEX) and operational expenditure (OPEX). However, anaerobic digestion of POME produces methane gas which is 21 times more harmful than carbon dioxide. 1m3 of POME could generate 27m3 of biogas at standard temperature and pressure with approximate caloric value of 20 MJm-3 under optimum conditions Thus, methane capturing biogas plant to address sustainability issue is included as part of effluent treatment plant. Many mills start to utilise the biogas energy to replace palm kernel shell which could be sold as renewable solid fuel. Although untreated biogas may be good enough for boiler fuel, internal combustion engines need a fairly homogeneous fuel with methane (CH4) content up to 80 % and hydrogen sulphite (H2S) content less than 200 ppm in order to ensure the optimum engine performance. Water scrubber system is widely used in gas purification. Computer aided biogas purification system simulation involving water scrubber and flashing drum is presented in the effort to produce IC engine fuel. ChemCAD simulation result shows that POME biogas purification process is feasible at 10 bar pressure and 25°C ambient temperature.
Referendum Campaigns in the Digital Age: Towards (More) Comparative Analyses in Hybrid Media Systems
Authors: Udris Linards , Eisenegger Mark
Published: January 2023

Referendum campaigns, which happen in many countries on the national or sub-national level, are highly important and special periods of political communication. Unlike elections, however, referendum campaigns are understudied phenomena. This thematic issue addresses patterns of referendum campaigns, which increasingly take place in digital and hybrid media environments, where political actors conduct campaigns through various channels, news media react to and shape debates on social media, and citizens receive a large share of political information from traditional and digital media. In this editorial, we provide a short overview of how research on referendum campaigns has evolved and how it has started to shift its attention away from news coverage and toward the role of campaign actors and the citizens who use (or engage with) search engines and social media platforms. The articles in this thematic issue reflect this shift but also show that news media remain important actors in referendum campaigns. Finally, we outline further research steps, which should include even more holistic analyses of the hybridity of referendum campaigns and hopefully more comparisons across cases.
Wealth and Welfare: Do Private and Public Safety Nets Compensate for Asset Poverty?
Authors: Rapp Severin , Humer Stefan
Published: January 2023

Economic shocks test the resilience of families around the world. Lockdowns, extended periods of unemployment, and inflation challenge the capabilities of private households to maintain their living standards whilst keeping their budgets in balance. Asset poverty is a concept invoked frequently to measure the capacity of private households to mitigate income loss by relying exclusively on their savings. In contrast to conventional asset poverty measures, we quantify the combined cushioning effect of private and public safety nets. Highlighting the importance of public safety nets and familial networks, this article devises a modified concept of asset poverty: Rather than purely simulating a household’s asset decumulation without replacement income, the modified indicator accounts for replacement income in a static setting. The empirical assessment of modified asset poverty in Europe and America combines harmonised microdata on household finances with simulations of institutional rules set by social insurance systems. Our results reveal how differences in social relations and institutional rules shape cross‐country variation in the vulnerability of private households. We find that, in contrast to the US, where the asset poverty of families is particularly low, households in most European countries are less vulnerable because generous social security systems coexist with low private assets. However, in some European countries, benefit generosity decreases the longer income losses last, exposing time dynamics in vulnerability. Complementing social insurance mechanisms, in countries such as Greece, households are more likely to receive financial support from family or friends. Cross‐national heterogeneity in vulnerability suggests that a shock may have different implications across countries.
Tax on Self-Employed Income in the Republic of Belarus
Authors: Boziev R. M.
Published: January 2023

The paper discusses tax on self-employed income in the Republic of Belarus. This state, together with the Russian Federation, forms a single Union State and is part of the most important supranational formation in the post-Soviet space: the Eurasian Economic Union. In this regard, the experience of legal regulation of self-employed taxation in the Republic of Belarus is important for the Russian theory of tax law, since it allows us to determine the vectors for further harmonization of the tax legislation of the EAEU member states, without which full-fledged economic integration is impossible. The conducted analysis of the current system of taxation of income received by self-employed in the Republic of Belarus allows us to state that it is more variable than the similar system in Russia. Moreover, in Belarus, both civil and tax legislation more clearly defines the status of self-employed citizens, and the state seeks to stimulate this type of activity. At the same time, the introduction from January 1, 2023 of a tax identical to the Russian tax on professional income allows us to conclude that Russia has chosen the right way to tax self-employed citizens through introduction of advanced digital technologies into this mechanism that provide information exchange with the tax authorities.
Hospitality and Identitarian Tensions
Authors: Lind Andreas Gonçalves , Nobre Bruno , Pinto João Carlos Onofre , Barroso Batista Ricardo
Published: January 2023

The imperative to practice hospitality constitutes a mark of Western civilization. Already in Homer’s Odyssey, the hero Ulysses punishes Polyphemus for not having respected the obligation of hospitality towards him and his companions. In fact, hospitality has been a constitutive element of the West, marked by linguistic, cultural, and religious differences, in a world whose borders are supposed to be well defined. In his discussion of hospitality, Derrida shows how Socrates, in Plato’s dialogue The Apology of Socrates, places himself in the position of a foreigner. In fact, Socrates presents himself as foreigner, that is, someone who is alien to the language and procedures of the court that is judging him. According to Derrida, he shows, in this way, the extent to which the foreigner is forced to ask for hospitality in a language he does not know. The court reduces Socrates to the other, the different. Moreover, the court forces him to deny his difference, his own identity, asking him to adapt himself to a system that he does not control. The paradox arises when Socrates, who regrets being regarded as a foreigner, asks the court to treat him at least as a foreigner. He feels so outraged that he asks to be granted at least the rights of a non-national. In doing so, Socrates shows how recognizing the rights of the foreigner generates hospitality but, at the same time, also limits it. Whenever a human being is recognized as human being, he or she will necessarily be seen as another, as someone different. This person will have to adapt him or herself to a system, culture or world that will define him or her as a foreigner. In short, in the phenomena that we tend to see as hospitality there is always a certain hostility. In a world of ongoing migratory crises, and in the context of a return to nationalisms of exclusion combined with populisms of prejudice and aversion to those who are different, it becomes imperative to rethink the ethics and politics of hospitality. In this context, Derrida’s distinction between conditioned and unconditioned hospitality can be useful.
L’hospitalité langagière, point critique de la philosophie comparée entre la Chine et l’Europe
Authors: Vendé Yves
Published: January 2023

The history of the philosophical exchanges between China and the West is the history of the translations between the two traditions. On the western side, after the Jesuits, the range of translators became gradually broader. On the Chinese side, many intellectuals introduced Western classics in their language in the twentieth century. This led several historians to argue that Chinese philosophy took off with the translation-comparison of both traditions. However, not all comparisons are of equal value. Thus, translation in philosophy implies comparing concepts or arguments and considering all the cultural references involved. This means taking a risk and accepting a limit. A risk is to be taken because translating interprets a “foreign thought” according to one’s context. This implies disclosing one’s presuppositions. There is a limit because transitioning from one set of references to another implies welcoming a part of “untranslatable” that always remains. According to Ricoeur’s words, “linguistic hospitality” is required here. This article first presents two interpretations of the translation-comparison processes. In the last part, it describes the necessity of linguistic hospitality in the context of Comparative Philosophy.
Rereading Notions of ‘Reciprocity’ and ‘Hospitality’ in the Work of Martin Buber and Jacques Derrida
Authors: Froy Thomas
Published: January 2023

This text aims to initiate a dialogue between the works of Martin Buber and Jacques Derrida with regard to the notion of ‘reciprocity’. It is my contention that a reexamination of Buber’s notion of relation will reveal a reflection, devoid of any notions of ‘symmetry’, which strongly indicates a point of continuity with Derrida’s late thinking on hospitality. The following text, therefore, aims to provoke a reexamination of Buber’s thinking on the home, at the centre of which stands the notion entirely opposed to ‘symmetry’: namely, ‘reciprocity’. The hypothesis of this text, then, is that when it comes to thinking of dwelling, Buber and Derrida share a ‘relational’ way of thinking, which foregrounds the relation between – in Buber’s case – the relations between man and God, man and man, and man and the Land, and – in Derrida’s case – between guest and host; in addition, I will attempt to show that Derrida’s work on hospitality – in particular, his introduction of a notion of ‘identity’ – produces a necessary contribution, or response, to Buber’s notion of ‘dwelling as reciprocity’. I will conclude by reflecting upon the reciprocity of this dialogue between the work of Martin Buber and Jacques Derrida.