bluuebunny/crossref_metadata_2025 huggingface dataset:
An Experimental Study on the Effect of Nano Zinc Oxide on Reflective Coatings and Building Roof Temperatures
Authors: Asaad Wurood , Shaker Lina M. , Mahdi Ahmed
Published: November 2024

Most roofs on Earth are made of dark materials. Dark roof surfaces can retain heat better than light ones; in Iraq, summer time temperatures on the roofs of dark buildings reached 70–80 degrees Celsius in July and August. The effects of this temperature rise are detrimental to cooling and energy consumption. To lessen heat transfer into the building, use reflective surfaces that can reflect infrared radiation waves. Cool roofs have both short-term and long-term advantages. They can reduce a building's annual air conditioning energy consumption by up to 15%, extend the life of the roof and its service life, improve the energy efficiency of roofs particularly those with inadequate insulation at the front of the roof improve thermal comfort in buildings without air conditioning, and lower greenhouse gas emissions and air pollution. Solar heat is one of the main factors affecting the durability of roofing membranes, according to research and real-world experience with the deterioration of these materials over time. High solar reflectance materials can reflect more sunlight and maintain their coolness in the sun. This study examines a low-cost composite cool coating that uses 60% calcium carbonate and demonstrates a 15°C drop in surface concrete temperature for roof buildings when compared to an uncoated surface. Additionally, compared to 30%wt CaCO3, the effect of 60%CaCO3 in composite coating reduces adhesion strength. According to the study, the weight of CaCO3 in the composite coating increases while adhesion strength, surface roughness, and particle homogeneity distribution decrease. Conversely, the maximum weight of CaCO360% weight percent exhibits good IR reflectance and less tribological properties. While preserving good infrared reflectance, adding 10% ZnO to the coating solution (60% CaCO3/PVac) improves tribological properties. The adhesion strength of the 60% calcium carbonate polymer composite paint increased from 10.9 MPa to 40.2 MPa when the nanomaterial was present, while this material maintained the superior optical qualities of infrared reflection. The coefficient of thermal expansion varies between concrete and coating solutions. For instance, the coating that has 10% weight added ZnO has a peel resistance coefficient of 8*10-6 1/K. The 60%CaCO3/10%ZnO/PVac coating effectively lowers the temperature by 15–12 °C when applied to a building roof.
Optimization of FDM 3D Printer Process Parameters to Minimize Dimensional Errors with PLA Material Using Response Surface Methodology
Authors: Maneengam Apichit , Limlay Tattapong , Kongsin Tanongsak , Assawarungsri Tossaporn , Laotaweesub Wannalak , Suwankan Patpimol , Ubontip Kanlaya
Published: November 2024

This paper presents a response surface methodology to fit a second-order response surface model aimed to finding process parameters to minimize length error (LE) and diameter error of the cylindrical shafts (DE) in fused deposition modeling (FDM) using polylactic acid (PLA) material. The process parameters in this study included layer height (LH), which varied from 0.1 to 0.4 mm, and print speed (PS), which ranged from 20 to 60 mm/s, while other parameters were set to constant values. The results showed that optimal process parameters obtained in this study significantly lower dimensional errors than the initial parameterization recommended by UltiMaker Cura software.
Feasibility Study of Multi-Layer CFRP Press Molding Method
Authors: Tanaka Hidetake , Thangkasemvathana Tanatat , Nishimura Yuki , Yilmaz Emir
Published: November 2024

This study examines the feasibility of utilizing the press forming method on multi-layer, multi-orientation continuous CFRP preform produced by the additive manufacturing (AM) technique. The 5-layer preforms with fiber orientations of 45° and -45° impregnated in Nylon-6 resin layers were made by a 3D printer, and press-formed in varying temperatures and pressures. Optimal forming outcomes were determined by qualitative evaluations of the surface finish, fiber impregnation, resin flow, and quantitative observations on shape variations by comparison with the mold dimensions. Experimental results showed that the molding temperature of 220°C and pressure between 0.5MPa - 1MPa could produce preforms with optimal surface conditions. There was almost no void of bubble defects, no excess resin flow, and a smooth transition was established between the carbon fiber and the matrix resin layers while allowing the full mechanical strength properties to be realized. The formed preform evaluations confirmed that the press molding method is feasible on multi-layer, multi-orientation continuous CFRP with optimal surface conditions.
Recovery and Size-Tuning of Amorphous Silica from Geothermal Scales in Batangas, Philippines
Authors: Oyales Mitch-Irene Kate Galvan , Damian Kirk Benedict Beau T. , Lao Tiffany Louise B.
Published: November 2024

Scale deposits in geothermal power plants are well-known potential sources of minerals. Extensive research in mineral recovery is crucial due to the considerable variability in scale composition and geochemistry based on location. Geothermal scales from Batangas, Philippines, were used to synthesize size-modified amorphous silica (SiO2) via sol-gel method. Initial analyses employing x-ray fluorescence spectroscopy (XRF), total dissolved solids (TDS), electrical conductivity (EC), and pH measurements confirmed that the scale is rich in silica and salts at neutral pH. Then, the effect of varying scale concentration, precipitation pH, and aging time on the particle size distribution of recovered amorphous silica were investigated. Dynamic light scattering (DLS) for particle size analysis (PSA) revealed that the sample with 2.5% (w/v) scale precursor in NaOH and precipitated until pH 10 had the lowest average cumulant diameter (1.66 μm). Moreover, the synergy of precipitation pH and aging time was found to significantly affect the polydispersity index and cumulative diameter of precipitated SiO2 based on 23 factorial ANOVA at 0.05 significance level. X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) confirmed that the precipitates were amorphous SiO2 with spherical morphology. This study proves the viability of utilizing geothermal scales from Batangas, Philippines for the synthesis of amorphous SiO2 with controlled particle size, which is a potential filler for composite materials.
Examination of Microstructure, Mechanical Properties, and Fatigue Strength in a Wire Arc Additively Manufactured Material Comprising Dissimilar Materials: AISI 316L Stainless Steel and Carbon Steel
Authors: Hietala Mikko , Keskitalo Markku , Jaskari Matias , Arvola Jari , Järvenpää Antti
Published: November 2024

This study provides a comprehensive investigation into the microstructure, hardness, tensile strength, and bending fatigue behavior of a Wire Arc Additively Manufactured (WAAM) component composed of dissimilar materials—Carbon Steel (CS) and 316L stainless steel. Microscopic analysis reveals distinct microstructural characteristics, such as equiaxed ferrite grains in WAAM CS and a coarse columnar structure with delta-ferrite phases in WAAM 316L. A macroscopic phase map indicates a predominantly Body-Centered Cubic (BCC) structure near the interphase, suggesting element migration between CS and 316L due to high heat input. Higher magnification scans highlight martensitic structures on both sides of the interphase, with the CS side exhibiting larger grain sizes. Hardness assessment along the built direction shows a peak hardness of 407 HV near the interphase on the 316L side, contrasting with the CS side's average interphase hardness of 316 HV due to larger grain sizes. The yield strength of both WAAM CS and WAAM dissimilar material was consistently measured at 392 MPa. In comparison, WAAM 316L exhibited a slightly lower yield strength of 359 MPa. Notably, WAAM 316L demonstrated the highest tensile strength among the materials, reaching 656 MPa. Meanwhile, WAAM CS displayed a robust tensile strength of 503 MPa, and the WAAM dissimilar material exhibited a yield strength of 520 MPa. In terms of elongation, WAAM CS and WAAM 316L showcased values of 44.9% and 49.6%, respectively. On the other hand, WAAM dissimilar material exhibited a somewhat lower elongation of 20.4%, suggesting a different mechanical behavior in terms of ductility. Bending fatigue tests on WAAM 316L, WAAM CS, and the dissimilar material reveal a fatigue limit of approximately 225 MPa for WAAM 316L, 210 MPa for WAAM CS, and approximately 210 MPa for the dissimilar material. In the low-cycle and medium-cycle regimes, the dissimilar material exhibits slightly superior fatigue strength, potentially due to its marginally higher static strength. Notably, consistent fractures on the CS side during fatigue tests underscore a recurring behavior in the dissimilar material.
Effect of Iodine Doped Pentacene Thin Film on the Performance of Organic Light Emitting Diode
Authors: Saikia Dhrubajyoti , Sarma Ranjit
Published: November 2024

The study investigated the effect of iodine-doped pentacene film as a buffer layer in an organic light-emitting diode (OLED). In this study, an ITO (indium tin oxide)-based sample is used as a reference device for comparative purposes. In OLED devices, the buffer layers were deposited using the doping of iodine vapor with the pentacene materials under proper conditions. The thermal treatment of the doped pentacene film results in increasing the conductivity of the buffer layer. Surface morphology for the bilayer anode was carried out by FESEM (Field Emission Scanning Electron Microscope) analysis. In our work, maximum luminance of 2345 cd/m2 and current efficiency of 5.4 cd/A are obtained, along with more stability performance under annealing treatment in the device structure of FTO/iodine-doped pentacene (30 nm)/TPD [N, N′-Bis(3-methyl phenyl)-N, N′-diphenylbenzidine] (44 nm)/Alq3 [Tris(8-hydroxyquinoline)aluminum(III)] (52 nm)/LiF (lithium fluoride) (5 nm)/Al (aluminum) (110 nm).
Assessing groundwater quality in the northwestern coastal area of Sri Lanka using multivariate statistical techniques
Authors: Weerasinghe N. M. A. N. , Nawarathna L. S. , Pitawala H. M. T. G. A.
Published: November 2024

The objective of the present study was to assess groundwater quality in the northwestern coastal region of Sri Lanka by analyzing hydrogeochemical data using multivariate techniques. The study examined the relationship between water quality and sources influencing groundwater quality and proposed useful statistical tools for water resource management. Descriptive, comparative, correlation, factor analysis (FA), and discriminant analysis (DA) were among the techniques used. The water quality in terms of electrical conductivity (EC), total dissolved solids (TDS), and dissolved nitrate and phosphate concentrations of the northwestern coastal area, where different aquifer conditions prevailed, were compared, and differences in the mean concentrations of the above parameters were identified. The study also employed ridge regression and support vector machines (SVM) to predict nitrate levels and validate the results using a 70:30 train/test split. The analysis found that the mean concentrations of EC, TDS, and HCO3- are higher in the sandy aquifer area, while Fe2+ and PO43- are higher in the regolith aquifer area. EC, TDS, PO43-, and HCO3- in the hard-rock aquifer area exceed permissible limits. Factor analysis identified four factors contributing to pollution, and a linear discriminant model classified all observations with 99.9% accuracy. The water quality index for Kalpitiya, Vanathavillu, and Katana-Negombo areas was 68.1, 99.2, and 287.9, respectively, while the World Health Organization (WHO) cutoff was 50. The use of multivariate statistical techniques demonstrated the value of analyzing hydrogeochemical data to gain valuable insights into the complex interplay of factors affecting groundwater quality. The SVM model, using a linear kernel, was identified as the best model to predict nitrate levels. A combination of statistical analyses reveals that, with the exclusion of a few wells, the groundwater in the study area is polluted and inappropriate for human consumption or culinary purposes. Nonetheless, the inhabitants persist in utilizing it as their primary source of drinking water. This study reveals the combination of statistical analyses is useful for the management of groundwater resources.
Antimicrobial activities and bacteriocins of lactic acid bacteria isolated from Nigeria indigenous fermented cowmilk “nunu”
Authors: Saliu B. K. , Abdulkadir H. , Dadzie V. O. , Alabi A. A. , Salami R. I. , Ajewole A. E.
Published: November 2024

Nunu is a nutritious fermented yoghurt-like milk beverage that can serve as a source of lactic acid bacteria (LAB) with antimicrobial and bacteriocin potentials. Nunu samples were screened for LAB with antimicrobial activity against test organisms. Three LAB, namely Lactobacillus parafarraginis OCLP1, L. fermentum CSL58 and L. buchneri MZE12 out of a total of 14 isolates produced antimicrobial activity against Bacillus anthracis CHF-2011-32b, B. cereus DHM5-1, Providencia vermicola KSVDL-09-71600, P. rettgeri SIRT3, P. stuartti SILT11 and other test organisms. Antimicrobial factors were assayed in LAB cell-free extracts (CFE), neutralized CFE, and ammonium sulphate precipitants of the CFE, and Lactobacillus parafarraginis OCLP1 demonstrated highest activity with zone of inhibition = 20.33±3.51 mm­, 13.33±1.09 mm and 25.33±2.52 mm respectively. The CFE of the LAB especially L. parafarraginis OCLP1 demonstrated wide activity spectra by inhibiting both the gram-positive and gram-negative bacteria tested. Result of plasmid curing of the LAB indicate that the bacteriocins of L. parafarraginis OCLP1 was plasmid-encoded while the others have their gene clusters on the chromosome. This study concluded that bacteriocin-producing LAB can be found in “nunu” and recommend the use of the isolated LAB as starter in fermented food production after ensuring their safety through toxicological studies.
Evaluation of the anticancer properties of the phytochemicals present in Annona muricata
Authors: Samaratunga S. , Katuwavila Nuwanthi P.
Published: November 2024

Cancer is a complex disease characterized by the unrestrained proliferation and dissemination of abnormal cells. The issue continues to be a notable public health concern on a global scale, with millions of new cases and fatalities being reported annually. Despite significant advances in cancer treatment, it remains a major challenge due to the high cost and toxicity of current therapies. Phytochemicals naturally found in plants are crucial resources for developing novel drugs and potential cancer therapies. The clinical efficacy of these anti-cancer agents has been demonstrated against diverse neoplastic cell lines. Additional investigation in this field can result in improved cancer therapies. Among many other plants effective against cancer, this literature review explores the anti-cancer properties of Annona muricata, a plant commonly known as soursop, which is a tropical plant species native to Central and South America, the Caribbean, and West Africa known for its edible fruit which has some medicinal merits, but also some toxicological effects. Annona muricata has been traditionally used for medicinal purposes, including cancer treatment. Acetogenins, alkaloids, phenolic compounds, and other active compounds are only a few of the phytochemicals that this review cites as being present in A. muricata. The review also looks into A. muricata’s biological abilities to fight lung, liver, prostate, colon, pancreas, and breast cancers. The toxicity of A. muricata and possible adverse effects are also covered in the review. The review also looks at the usage of nanoparticles with A. muricata as a cancer treatment. Overall, this literature review provides valuable insights into the potential anti-cancer properties of A. muricata and its potential as a therapeutic agent in cancer treatment.
APORTACIONES DE LA UNIVERSIDAD AUTÓNOMA DE BARCELONA A LA CONSTRUCCIÓN DE UNA DIDÁCTICA DE LA HISTORIA EN CHILE
Authors: Valencia Lucía , Villalón Gabriel , Pagès Joan
Published: November 2024

Este artículo hace una revisión de los trabajos realizados por investigadores chilenos en los programas de máster y doctorado en Didáctica de la Historia y de las ciencias sociales de la Universidad Autónoma de Barcelona (UAB). Para esto hemos analizado y agrupado los trabajos en las líneas de investigación desarrolladas en el ámbito de la Didáctica de la Historia y de las ciencias sociales. Este análisis nos muestra que la estrecha relación entre el Departamento de Didáctica de las Ciencias Sociales, Historia y Geografía de la UAB y los investigadores chilenos ha sido relevante para la construcción de una Didáctica de la Historia en Chile.
PONER EL TIEMPO PASADO EN DISPOSICIÓN DEL APRENDIZAJE: LA RAZÓN DE SER DE LA DIDÁCTICA DE LA HISTORIA
Authors: González Gallego Isidoro
Published: November 2024

PONER EL TIEMPO PASADO EN DISPOSICIÓN DEL APRENDIZAJE: LA RAZÓN DE SER DE LA DIDÁCTICA DE LA HISTORIA
EPISTEMOLOGÍA DE LA HISTORIA E INVESTIGACIÓN EN EDUCACIÓN HISTÓRICA: NARRACIONES DE ALUMNOS PORTUGUESES SOBRE HISTORIA CONTEMPORÁNEA
Authors: Barca Isabel
Published: November 2024

La exploración de la formación de la conciencia histórica de los jóvenes constituyó uno de los objetivos esenciales en una investigación reciente en Brasil y Portugal. En este ámbito, se desarrolló un estudio con 82 jóvenes portugueses, alumnos del 9º grado, a quienes se les propuso narrar la historia del país y del mundo en los últimos cien años. Los textos de los jóvenes, reunidos entre 2010 y 2011, fueron analizados según un marco epistemológico que permitió inferir sentidos de identidad, nociones de cambios en la Historia y posiciones personales frente a la historia vivida, basándose en la estructura narrativade los textos individuales y los mensajes nucleares transversales a los mismos. Estudios como éste, sobre las ideas de los jóvenes respecto a la Historia, buscan contribuir como diagnóstico y pistas útiles para el diseño de prácticas consistentes en la enseñanza de la Historia, y como tal, ser potenciado a través de modelos de formación continua que promuevan el perfil del profesor-investigador social.
Reportaje: Los Temas Candentes en el aula: Diversas Miradas
Authors: Equipo Andamio
Published: November 2024

Reportaje: Los Temas Candentes en el aula: Diversas Miradas
Otras publicaciones de enseñanza de la Historia
Authors: Andamio Equipo
Published: November 2024

Otras publicaciones de enseñanza de la Historia
CONCEPCIONES Y USO DEL PATRIMONIO POR PARTE DEL PROFESORADO DE GEOGRAFÍA E HISTORIA: UNA INVESTIGACIÓN EN CURSO
Authors: MOLINA PUCHE SEBASTIÁN
Published: November 2024

Este artículo muestra un proyecto de investigación actualmente en proceso en el que se pretende analizar la concepción y el uso que los profesores de ciencias sociales de Educación Secundaria dan a los diferentes elementos que constituyen el patrimonio cultural. En este trabajo pretendemos mostrar los principales objetivos que persigue esta investigación, la metodología y herramientas utilizadas, y aportamos una primera aproximación a algunos de los datos obtenidos en la misma. Se trata de datos totalmente provisionales, pero que ya ofrecen interesantes conclusiones provisorias sobre qué piensan los profesores de Geografía e Historia acerca del patrimonio como recurso didáctico para la enseñanza de la historia, y cómo suelen utilizarlo en el aula.
LA EDUCACIÓN PATRIMONIAL COMO HERRAMIENTA PARA LA EDUCACIÓN INCLUSIVA: DEFINICIÓN, FACTORES Y MODELIZACIÓN
Authors: MARTÍNEZ GIL TÀNIA , LÓPEZ BENITO VICTORIA , SANTACANAMESTRE JOAN
Published: November 2024

El contenido del presente artículo presenta el planteamiento conceptual y las distintas fases de investigación de un proyecto basado en el uso de la Educación patrimonial como herramienta para la inclusión cultural. Su principal objetivo es la creación de modelos de educación inclusiva para la educación reglada en el ámbito español empleando la educación patrimonial. Por tanto, supone una función innovadora de la educación patrimonial ya que no pretende educar en el Patrimonio o para el Patrimonio para su conocimiento o su valoración, sino que va más allá, educar a través del Patrimonio para generar contextos educativos inclusivos en los que los factores de exclusión cultural se minimicen lo máximo posible. Para ello, en primer lugar, era necesario definir los conceptos fundamentales del proyecto como son los de exclusión e inclusión cultural y se han establecido los principales factores de exclusión cultural a través de las voces de expertos implicados en este ámbito empleando la técnica de los focus groups tal y como se argumenta en el artículo. En él también se enuncia cuál será la segunda fase de investigación del proyecto que consiste en contrastar los resultados de la primera fase del proyecto con los agentes a los que está orientado el proyecto; los alumnos de tercero y cuarto curso de la educación secundaria obligatoria en España, de tres ámbitos geográficos diversos recopilando así una gran variabilidad y heterogeneidad de perfiles. Lo que aportará una gran riqueza para el posterior diseño de estrategias y modelos didácticos de educación inclusiva.
CAMBIOS Y CONTINUIDADES DE LA ENSEÑANZA DE LA HISTORIA EN LA ESCUELA NORMAL MEXICANA: DEL MODELO PATRIÓTICO A LA EDUCACIÓN HISTÓRICA
Authors: CASTAÑEDA MENDOZA EDITH
Published: November 2024

La enseñanza de la historia en México ha sido fundamental para la edificación de concepciones patrióticas. Después de la independencia la educación histórica fue una herramienta fundamental para la construcción de identidad nacional, establecer vínculos culturales, tradiciones e ideales de un país que comenzaba a formarse. En esta lucha por la construcción de un modelo de identidad mexicana, las escuelas Normales fueron y han sido encomendadas como portavoces de los cambios sociales e ideales de los gobiernos en turno. Sin embargo, en pleno siglo XXI se propone un modelo de enseñanza de la historia en las Escuelas Normales mexicanas que hace cuestionarse al estudiante normalista sobre ¿qué estudia la historia? y ¿cómo lo hace? Así, mediante el uso de fuentes primarias y secundarias pueda cuestionarse y debatir los sucesos pasados para comprender su presente y no aceptar adoctrinamientos como verdades absolutas.
ENSEÑANZA-APRENDIZAJE DE HISTORIA Y CIENCIAS SOCIALES. POTENCIANDO LOS APRENDIZAJES DISCIPLINARIOS CON LA WEB 2.0
Authors: Villegas Dianta Cristian Adrian
Published: November 2024

En el siguiente artículo se propone un modelo de construcción de secuencias digitales de aprendizaje, a partir del desarrollo de objetos digitales...
CONVOCATORIA REVISTA ANDAMIO
Authors: Andamio Equipo
Published: November 2024

El Instituto de Historia de la Pontiﬁcia Universidad Católica de Valparaíso tiene el agrado de convocar a profesores e investi-gadores en Didáctica de la Historia, así como a profesores de Historia en formación, principiantes, mentores y en ejercicio, a participar en Andamio. Revista de Didáctica de la Historia, pu-blicación gestionada por el área de Didáctica del Instituto de Historia de la Pontiﬁcia Universidad Católica de Valparaíso.
NORMAS DE PUBLICACIÓN DE LA REVISTA
Authors: Andamio Equipo
Published: November 2024

NORMAS DE PUBLICACIÓN DE LA REVISTA
ÉTICA DE PUBLICACIÓN Y DECLARACIÓN SOBRE NEGLIGENCIA
Authors: Andamio Equipo
Published: November 2024

ÉTICA DE PUBLICACIÓN Y DECLARACIÓN SOBRE NEGLIGENCIA
PROYECTO SATURNO: EL PATRIMONIO LOCAL PARA EL APRENDIZAJE DE LA HISTORIA
Authors: Ponce Gea Ana Isabel
Published: November 2024

En el marco de una tesis doctoral, enfocada hacia la medición y desarrollo de las habilidades implicadas en el proceso de construcción histórica, se articula un proyecto didáctico desarrollado en la etapa de Educación Secundaria Obligatoria durante los cursos 2016/2017 y 2017/2018, en el contexto español. El proyecto, denominado Proyecto Saturno, utiliza el patrimonio local para el trabajo de algunos de los estándares de aprendizaje presentes en el currículo, entendiendo el patrimonio como fuente histórica a par-tir de la cual desarrollar un proceso de investigación. En el proceso de construcción del conocimiento histórico el alumno habrá de utilizar diferentes habilidades, relacionadas con el pensam-iento científico, crítico y creativo, que le permitirán llegar a la elabo-ración del discurso histórico, es decir, sus narrativas particulares; lo que, en el plano social, encuentra conexión con la construcción de identi-dades colectivas múltiples y abiertas. En este trabajo se recoge la descripción de las siete propuestas didácticas llevadas a cabo hasta el momento, señalando sus aspectos básicos y aquellas habilidades fundamentales que son trabajadas. Pese a que el proyecto sigue en ejecución y será con su finalización y la aplicación del postest cuando obtengamos resultados válidos, hoy podemos reconocer logros: la colaboración entre universidad- escuela y el cambio en la dinámica para la enseñanza-aprendizaje de la historia.
LA LUDIFICACIÓN COMO UNA HERRAMIENTA PARA LA IMPLEMENTACIÓN DEL APRENDIZAJE BASADO EN JUEGOS EN LA ASIGNATURA DE HISTORIA, GEOGRAFÍA Y CIENCIAS SOCIALES: UNA SECUENCIA DIDÁCTICA PARA LA PRIMERA UNIDAD DE 7° BÁSICO
Authors: Álvarez Rosso Mauro , Saavedra Lincopán Guillermo , Vásquez Cornejo Fabián
Published: November 2024

El presente artículo contribuye a profundizar el concepto del Aprendizaje Basado en Juegos mediante el desarrollo de una se-cuencia didáctica para 7° básico a través de la ludificación. Dicho ejer-cicio pretende ahondar en las posibilidades que ofrece la enseñanza de la Historia en el contexto chileno, considerando las oportunidades y exigencias del mismo.
Deconstruir una historia heteronormada en las aulas.
Authors: Admin Admin , Benavides Catalina , Araya Jorge , Meneses Belén
Published: November 2024

Desde la didáctica de las ciencias sociales, una educación democráticaimplica luchar contra la invisibilización de distintos grupos humanos (Massipet al., 2020). Entre ellos, la disidencia sexual (DS) continúa siendo excluidapor la resistencia del sistema patriarcal y heteronormativo (Ortega, 2020).La investigación aborda las potencialidades y limitaciones de la visibilizaciónde la DS en la enseñanza de la historia escolar. Para ello, se analizanentrevistas realizadas a dos docentes en ejercicio y una profesora de formacióncontinua, pudiendo reconocer tres tipos de docentes. El docente de perfilModerado-Heteronormado, reconoce efectos positivos de incluir a la DS, perosolo en formación ciudadana. La docente de perfil Moderada-Aliada, consideraimportante incluirlos en la asignatura de Historia porque es una realidadsocial actual, pero aún no lo ha trabajado en sus propias clases. La docente deperfil Transgresora-Deconstruida, afirma la existencia de una intencionalidadheternormativa del currículum al excluir a las DS en las distintas temáticas,por lo que sostiene que es un deber educativo visibilizarlas de forma transversalen todo los contenidos históricos y sociales.Este estudio pretende contribuir a pensar en estos otres excluidos delgrupo de invisibilizados. De esta manera, se puede avanzar en una verdaderaeducación para la ciudadanía, donde todas las personas, expresiones ycolectividades, tengan presencia y relevancia para comprender la realidad yconstruir un mundo más inclusivo.
Competencias digitales, históricas y geográficas y de comunicación patrimonial: los storymaps como recursos de aprendizaje en la formación del profesorado de ciencias sociales
Authors: Admin Admin , González Rafael de Miguel , Gracia Pilar Rivero , Kratochvil Ondrej
Published: November 2024

La presente contribución se fundamenta conceptualmente en los modelos deformación por competencias, tanto transversales -y en especial las digitales-, comoen las competencias específicas, históricas y geográficas, y metodológicamente en elproyecto nacional de I+D+I CIVITAS III, y expone el estudio de caso de los recursosproducidos por los estudiantes del Master en Profesorado en Educación Secundariade la Universidad de Zaragoza. Los futuros docentes han abordado a través de unaserie de storymaps, no sólo la adquisición de esas competencias digitales, sino la integraciónde las competencias propias de la didáctica de la geografía, de la didácticade la historia y de la didáctica del patrimonio en un único diseño instruccional. Deesta manera, se exponen los resultados alcanzados en adquisición de competenciasdigitales para la enseñanza de la sostenibilidad urbana y territorial, de la ciudadaníademocrática y de la conformación de cibercomunidades patrimoniales. Pero también,este artículo muestra que es posible superar la barrera, siempre presente en elprofesorado de ciencias sociales, de la disociación entre las tres principales disciplinasreferentes de la didáctica de las ciencias sociales.
A closure theorem for $\Gamma$-convergence and $H$-convergence with applications to non-periodic homogenization
Authors: Braides Andrea , Dal Maso Gianni , Le Bris Claude
Published: November 2024

In this work we examine the stability of some classes of integrals, in particular with respect to homogenization. The prototypical case is the homogenization of quadratic energies with periodic coefficients perturbed by a term vanishing at infinity, which has recently been examined in the framework of elliptic PDEs. We use localization techniques and higher-integrability Meyers-type results to provide a closure theorem by

\Gamma

-convergence within a large class of integral functionals. From such a result we derive stability theorems in homogenization which comprise the case of perturbations with zero average on the whole space. The results are also extended to the stochastic case, and specialized to the

G

-convergence of operators corresponding to quadratic forms. A corresponding analysis is also carried out for non-symmetric operators using the localization properties of

H

-convergence. Finally, we treat the case of perforated domains with Neumann boundary condition, and their stability.
Rectal varices vs hemorrhoids-diagnosis and management
Authors: Majid Zain , Yaseen Taha , Tasneem Abbas Ali , Luck Nasir Hassan
Published: November 2024

Rectal varices are an uncommon manifestation of portal hypertension. Although hemorrhoids can be seen in cirrhotic patients, distinguishing between rectal varices and hemorrhoids can be challenging. Furthermore, the underlying mechanism and treatment options vary. Hence, the correct identification is of utmost important. Through this letter, we highlight the features of both and listed the distinguishing points between the two etiologies.
Current status of drug therapy for alveolar echinococcosis
Authors: Jing Qin-Dong , A Ji-De , Liu Lin-Xun , Fan Hai-Ning
Published: November 2024

Alveolar echinococcosis (AE) is a chronic zoonotic parasitic disease caused by infection with Echinococcus multilocularis . AE is associated with a high mortality rate and poses a significant threat to human health. The primary treatment for AE is surgical resection of the lesions; however, owing to its long incubation period and insidious disease progression, many patients are diagnosed only after the onset of complications such as liver cirrhosis, jaundice, and portal hypertension, which preclude curative surgical intervention. For patients who are unwilling or unable to undergo surgery, lifelong administration of anti-AE medications is necessary. Benzimidazole compounds, such as albendazole and mebendazole, are the current mainstays of treatment, offering good efficacy. Nevertheless, these medications primarily inhibit parasite proliferation rather than eradicate the infection, and their long-term use can lead to significant drug-related toxic effects. Consequently, there is an urgent need to develop new therapeutic strategies that convey better efficacy and reduce the adverse effects associated with current treatments. Recent advancements in AE therapy include novel synthetic compounds such as antiviral agents, antibiotics, antineoplastic agents, immunosuppressants, and antiangiogenic agents, as well as natural compounds derived from traditional Chinese and Tibetan medicine. These new drugs show promising clinical potential because they interfere with parasitic metabolic pathways and cellular structures. This review aims to discuss recent research on AE drug therapy, including mechanisms of action, dosing regimens, signalling pathways, and therapeutic outcomes, with a goal of providing new insights and directions for the development of anti-AE drugs and summarizing current advancements in AE pharmacotherapy.
Reliability of neutrophil gelatinase-associated lipocalin in detecting acute tubular necrosis in decompensated cirrhosis: Systematic review and meta-analysis
Authors: Agrawal Nirav , Louis-Jean Scarlet , Ladiwala Zoya , Adnani Harsha , Kamal Ayesha , Karpman Mitchell , Fleisher Albert Steven , Singh Sanmeet
Published: November 2024

BACKGROUND

Acute kidney injury (AKI) in cirrhosis is common. The diagnosis of AKI in cirrhosis patients depends on clinical presentation and laboratory tests like serum creatinine. However, urine biomarkers could also be used to assess the type of AKI and the severity of the disease. We performed a systematic review with meta-analysis to evaluate the association with urine neutrophil gelatinase-associated lipocalin (NGAL) marker in identifying acute tubular necrosis (ATN) in patients with cirrhosis.

AIM

To assess the reliability of urine NGAL in the detection of ATN in patients with cirrhosis.

METHODS

We systematically searched MEDLINE and PubMed using keywords including “urine biomarkers”, “NGAL”, “kidney dysfunction”, and “cirrhosis” to identify relevant studies. Data was screened and extracted. Included studies assessed hospitalized cirrhosis patients with AKI using the urine NGAL biomarker. We synthesized the data using diagnostic odds ratio (DOR), comparative and descriptive analyses, and Cochran Mantel-Haenszel (CMH) statistics to evaluate heterogeneity.

RESULTS

Three thousand seven hundred and one patients with cirrhosis were analyzed from a total of 21 cohort studies. The DOR of 14 of those studies [pooled DOR: 22.150, (95%CI: 17.58-27.89), P < 0.0001] demonstrated a significant association between urine NGAL levels and its identification of ATN. Following stratification by cirrhosis status, heterogeneity was analyzed and showed a significant non-zero correlation between NGAL and AKI (CMH statistic = 702.19, P < 0.0001).

CONCLUSION

In patients with cirrhosis, the use of urine NGAL is a reliable biomarker for detecting ATN and identifying the etiology of AKI.
Evaluating the Impact of Velocity Advisory Systems on Fuel Economy of Passenger Vehicles: A Driver Simulator Study
Authors: Telloni Marcello , Farrell James , Mendez Luis , Ozkan Mehmet Fatih , Chrstos Jeffrey , Canova Marcello , Stockar Stephanie
Published: November 2024

With increasing emphasis on sustainable mobility and efficient energy use, advanced driver assistance systems (ADAS) may potentially be utilized to improve vehicles’ energy efficiency by influencing driver behavior. Despite the growing adoption of such systems in passenger vehicles for active safety and driver comfort, systematic studies examining the effects of ADAS on human driving, in the context of vehicle energy use, remain scarce. This study investigates the impacts of a driver speed advisory system on energy use in a plug-in hybrid electric vehicle (PHEV) through a controlled experiment using a driving simulator. A mixed urban highway driving environment was reconstructed from digitalizing a real-world route to observe the human driver’s behavior with and without driving assistance. The advisory system provided drivers with an optimized speed profile, pre-calculated for the simulated route to achieve maximum energy efficiency. Participants were instructed to navigate the simulated route while the vehicle's powertrain parameters, energy consumption, and overall dynamics were monitored. In the unassisted condition, drivers operated the vehicle according to their natural driving style. In the assisted condition, real-time speed advice was given to provide drivers with a more energy-efficient driving strategy through visual feedback. The results were analyzed to evaluate the impact of speed advisory systems on vehicle dynamics, powertrain use, and energy consumption metrics. The assisted driving condition resulted in smoother driving patterns, optimized powertrain operation, and notable fuel economy improvements compared to unassisted driving.
Numerical Investigation of the Combustion Process and Emissions Formation in a Heavy-Duty Diesel Engine Featured with Multi-Pulse Fuel Injection
Authors: Singh Harsimran , Kutkut Almoutazbellah , Pal Pinaki , Aggarwal Suresh Kumar , Li Hailin
Published: November 2024

Combustion in conventional and advanced diesel engines is an intricate process that encompasses interaction among fuel injection, fuel-air mixing, combustion, heat transfer, and engine geometry. Manipulation of fuel injection strategies has been recognized as a promising approach for optimizing diesel engine combustion. Although numerous studies have investigated this topic, the underlying physics behind flame interactions from multiple fuel injections, spray-flame-wall interaction and their effects on reaction zones, and NOx/soot emissions are still not well understood. To this end, a computational fluid dynamics (CFD) study is performed to investigate the effects of pilot and post injections on in-cylinder combustion process and emissions (NOx and soot) formation in a heavy-duty (HD) diesel engine. A full-sector CFD model of the HD engine employing detailed chemistry is validated against experimental data for in-cylinder pressure, heat release rate, combustion phasing, and engine-out NOx/soot and carbon dioxide (CO2) emissions at five load points. The validated CFD model is further leveraged to gain insights into the complex pilot-main and main-post injection interactions at low load (20%) and mid load (60%) conditions, respectively. The 20% load point consists of four fuel injections (two pilots, one main and one post injection), whereas 60% load point has three injections (one pilot, one main and one post). It is observed that pilot injections significantly alter the main flame structure by shifting reaction zones contributing to heat release from combined rich premixed + non-premixed + lean premixed zones to primarily non-premixed zones. Presence of pilot injection decreases NOx concentration (while shifting the contribution of NO2 towards NOx from 50% to 14%) and increases soot concentration. The local consumption of oxygen and less time available for main fuel-air mixing due to reduction in ignition delay (ID) caused by the pilot injection are the major reasons behind increase in soot. The investigation on post injection reveals that although post injection increases soot formation, it also increases soot oxidation, with soot oxidation dominating soot formation. This results in an overall reduction in soot emissions. Hydroxyl (OH) radicals play an important role in enhancing the soot oxidation rate. Furthermore, as the post start-of-injection (SOI) timing is retarded, both soot formation and oxidation decrease, with an overall increase in net soot emissions.
Effect of Premixing Ratio on the Deterministic Characteristics of Combustion Dynamics Butanol-Diesel RCCI Engine
Authors: Yadav Ratnesh Kumar , Mohite Avadhoot Abaso , Maurya Rakesh Kumar
Published: November 2024

The rising demand for vehicles has increased CO and HC emissions, worsening air quality and contributing to climate change, key issues under the clean development mechanism and UN SDG 13: Climate Action. Reactivity-Controlled Compression Ignition (RCCI) offers a promising solution to reduce PM and NOx while maintaining fuel efficiency. However, the cyclic variation of the RCCI engine remains an underexplored area in control strategies, necessitating further research for optimization in line with sustainable development goals. This study explores the impact of premixing ratios on RCCI engines fueled with butanol and the nature of cyclic variation to know the controllability. Tests were conducted on a single-cylinder diesel engine at 1500 rpm and constant engine load. The experiments reveal that increasing the premixing ratio from 45% to 60% decreases the heat release rate by 15%, Pmax by 10%, and IMEP by 12%. Recurrence Quantitative Analysis (RQA) confirmed strong deterministic combustion patterns, with determinism exceeding 85%. Multifractal Detrended Fluctuation Analysis (MFDFA) indicated that the Total Heat Release (THR) time series exhibited the least multifractality (∆α = 0.15) compared to Pmax and IMEP. These findings provide essential insights for optimizing RCCI control systems, enabling improved performance across varying operating conditions.
Spray Ignition of Primary Reference Fuels Blended with Ethanol and 2,5-Dimethylfuran
Authors: Bhattacharya Atmadeep , Kaario Ossi , Eraqi Basem , Sakleshpur Nagaraja Shashank , Sarathy Mani
Published: November 2024

Engine knocking poses a significant challenge for downsizing and boosting strategies in spark-ignition (SI) engines. In the event of knock, the unburnt fuel-oxidizer mixture auto-ignites after being compressed by the flame front and piston of an SI engine. Conventional knock is influenced by combustion chemistry and physical properties of the fuel. In this work, we present auto-ignition characteristics of primary reference fuel (PRF75), ethanol, 2,5-dimethylfuran, and their blends in Advanced Fuel Ignition Delay Analyzer (AFIDA). Three different pressures, i.e. 10, 15, and 20 atm and four different temperatures, i.e. 450, 500, 550, and 600 0C have been used as initial conditions. A weak negative temperature coefficient (NTC) behavior has been observed for PRF75 ignition in AFIDA in this work. Moreover, for PRF75, the ignition delay times at low temperatures have been observed to show weaker dependence on pressure in comparison to the high temperature cases. For ethanol and 2,5-dimethylfuran, the effect of pressure on ignition has been observed to be minimal. For the blends of PRF75 and ethanol (or 2,5-dimethylfuran), the ethanol (or 2,5-dimethylfuran) chemistry starts to dominate when ethanol (or 2,5-dimethylfuran) quantity reaches 20 % in the fuel blend. The present comparative study provides an idea about the total resistance to auto-ignition considering both physical and chemical properties of the fuel blends.
Failure of Power Steering Gears of the Heavy-Duty Trucking: A Tribological Investigation
Authors: García-Maldonado Miguel , Gallardo Ezequiel , Mozqueda-Flores Luis , Vite-torres Manuel
Published: November 2024

A power steering system helps the heavy-duty operator move the vehicle easily with the hydraulic pump that provides the fluid pressure and facilitating adequate operation. Some failures in the power steering system are due to external and internal factors that can reduce its service life. The external factors could be identified by ocular inspection but normally, due to internal failures, it is necessary to use a hydraulic pressure flow meter. However, this device makes it impossible to detect failures caused by the selected lubricant. This work aims to investigate the causes of power steering system seizure by using the tribological wear examination process and the lubricant characterization under some actual operation conditions. The lubricant characterization was carried out in a four balls tester using fresh and used samples of a re-refined oil based ATF, SAE 15 W40 and synthetic SAE 5 W30 oils at two temperatures. In general, the results showed an unsteady friction profile with regards to re-refined ATF oil at both temperatures tested. In all cases, the friction and wear of the synthetic and the engine oil showed good performance.
Emissions Analysis for a Hydrogen-Fueled Low-Pressure-Ratio Split-Cycle Engine
Authors: Eldakamawy Mohamed Hossam , Picard Mathieu
Published: November 2024

Recuperated low-pressure-ratio split-cycle engines represent a promising engine configuration for applications like transportation and stand-alone power generation by offering a potential efficiency as high as 60%. However, it can be challenging to achieve the stringent NOx emission standard, such as Euro 6 limit of 0.4 gNOx/kWh, due to the exhaust cylinder high intake temperature. This paper presents experimental investigation of hydrogen-air combustion NOx emissions for such engines for the first time. Experiments are carried out using a simplified constant-volume combustion chamber with glow-plug ignition. Two fuel injection techniques are performed: direct injection and injection via a novel convergent-divergent injector. For the direct injection scenario, NOx levels are unsatisfactory with respect to the Euro 6 standards over a range of operating temperatures from 200 °C to 550 °C. Recorded NOx levels can reach twice the permissible limit which necessitates the implementation of after-treatment techniques. Interestingly, NOx emissions are found to be less by around 50% in the case of the novel injector. The enhanced fuel-air mixing mechanism using the convergent-divergent injector increases the ignition delay and shifts the combustion flame towards the premixed conditions and results in lower NOx levels.
Experimental Test Bench Showcasing an X in the Loop Strategy for Fuel Cell Testing
Authors: Oswald Tancrède , Weiss Lukas , Wensing Michael
Published: November 2024

In the quest for reduced cost and shorter development times for fuel cell systems in industrial applications, two major issues arise. First, the electrochemical behavior of fuel cell systems is inherently difficult to predict. Second, testing fuel cell systems is resource intensive. These issues compound: Setting up an accurate model of a fuel cell system incurs long testing periods for model validation. Further, it does not guarantee acceptable results outside the tested range or for other membrane electrode assembly compositions.

To mitigate these two major issues an X in the Loop concept is proposed. Essentially, this is the direct integration of the test sample, here a single fuel cell, into the modelling environment of the whole system. In practice, two strategies with different levels of integration are defined.

The first strategy consists of initially deducing the operating parameters of the sample cell from the fuel cell system model. Then, setting them to the sample cell in the test bench. The response of the test sample is finally used to validate the designed system or update the parameters of the fuel cell model.

The second strategy is a step further towards the integration of the test sample into the model. Here, the core model of the fuel cell inside the fuel cell system model is completely replaced with the test sample, reducing the need for an accurate electrochemical model while improving the prediction of the behavior of the fuel cell system.

Compared to previously proposed testing concepts, here the balance of plants is directly integrated through a digital emulator, leading to a closer representation of the complete system. Furthermore, the test bench results are looped back to the model at run-time leading to a closer match between testing conditions and the real world as well a reduced impact of inaccuracies in the modelling of the fuel cell.

On the way to realizing this goal, an experimental test bench capable of showcasing working prototypes of the proposed operating strategies has been built.