Abstract The conservation of cultural heritage needs to be aligned with current sustainability policies. Therefore, this work aimed to assess the effectiveness of using kaolin residue, either totally or partially replacing bentonite, in Mário Mendonça de Oliveira's formulation for cleaning stone surfaces, in order to measure possible changes in the appearance or structure of Lioz stone. The influence of some variables, such as the application time of the plaster and the concentration of the clay minerals used, was evaluated. The experimental methodology consisted of drying and pulverizing the residue; quantifying and weighing the reagents; wet cleaning the rock; synthesis, application, and removal of the plaster. Throughout the research, analysis techniques were employed to characterize the starting materials, the products formed, and the alterations produced on the rock surface. After the wet cleaning process, there was a trend for increased brightness in all studied ranges, and an increase in brightness in all ranges where 100% kaolin plaster was applied during 7 and 14 days. policies Therefore residue bentonite Oliveiras Oliveira s surfaces variables used evaluated reagents synthesis research materials formed surface process 100 1 days 10

Resumo A conservação de bens culturais necessita estar alinhada com a política de sustentabilidade da atualidade. Assim, este trabalho teve como objetivo avaliar a eficácia do uso do resíduo do caulim substituindo total ou parcialmente a bentonita, na formulação de Mário Mendonça de Oliveira, para a limpeza de superfícies pétreas. E dessa forma avaliar possíveis alterações no aspecto ou na estrutura do lioz. Para tanto foram avaliadas a influência de algumas variáveis, como tempo de aplicação do emplastro e a concentração dos argilominerais utilizados. A metodologia experimental consistiu em: secagem e pulverização do resíduo; quantificação e pesagem dos reagentes; limpeza úmida da rocha; síntese, aplicação e remoção do emplastro. Ao longo da pesquisa foram empregadas técnicas de análise, para caracterizar os materiais de partida, os produtos formados e as alterações produzidas na superfície da rocha. Após a limpeza por via úmida houve uma tendência de elevação de brilho em todas as faixas estudadas; e um aumento do mesmo em todas as faixas em que foi aplicado o emplastro de 100% caulim, para os tempos de 7 e 14 dias. atualidade Assim bentonita Oliveira pétreas lioz variáveis utilizados reagentes rocha síntese análise partida estudadas 100 1 dias 10

Resumen La placa dental se forma a partir de una película adquirida como resultado de la alimentación que se deposita sobre las superficies dentales, por lo que un buen cepillado dental ayuda a mitigar los problemas a futuro que podría causar. Investigación de revisión sistemática, cuyo objetivo fue analizar la importancia del cepillado dental y comparar las características de un cepillado adecuado en la reducción de placa bacteriana en escolares. Se utilizó la metodología PRISMA; se revisaron bases de datos PubMed, SciELO, Scopus y Google Scholar; inicialmente Se trabajó con 1597 artículos, tan solo 18 cumplieron con el rigor científico. Concluyéndose que: los cepillos eléctricos, la técnica de Bass modificada y un adecuado cepillado debe incluir tiempo de uso, frecuencia y supervisión en caso de los niños.

Abstract Dental plaque is formed from a film acquired as a result of food that is deposited on dental surfaces, so good tooth brushing helps to mitigate the future problems that it could cause. The objective of this systematic review was to analyze the importance of tooth brushing and to compare the characteristics of adequate brushing in the reduction of bacterial plaque in school children. The PRISMA methodology was used; databases PubMed, SciELO, Scopus and Google Scholar were reviewed; initially 1597 articles were worked with, only 18 complied with the scientific rigor. It was concluded that: electric toothbrushes, the modified Bass technique and adequate brushing should include time of use, frequency and supervision in the case of children.

Resumo Conhecidas pela sua prolixidade e heterodoxia, as margens da arte medieval oferecem-nos, também em Portugal, um vastíssimo elenco de figuras, temas e estratégias de representação que importa interrogar e conhecer. Criadas para preencher vazios, para dinamizar superfícies e relações espaciais, para comentar e ampliar os efeitos previstos para o centro, foram também investidas de funções lúdicas, profiláticas e apotropaicas, tão importantes na cultura medieval mas ainda tão pouco estudadas (e tão difíceis de estudar) entre nós. Entre os diversos protagonistas destas margens da arte medieval, destaca-se, sobretudo a partir do final do século XIII, a figura do macaco, símile e extensão satírica e moralizadora do comportamento humano e, portanto, actor principal de um mundo às avessas que encontra nas margens o seu lugar natural. Atestando a naturalidade desta mesma relação, a primeira designação medieval para uma boa parte da figuração que hoje designamos por marginalia provém do termo babuíno, convocando a generalidade das espécies e comportamentos símios então conhecidos. Partindo desta afinidade, procuraremos identificar e, sempre que possível, interpretar algumas das mais significativas representações de macacos nos marginalia medievais em Portugal ao longo do século XIV, das quais se destacam dois estudos de caso inéditos.

Abstract Commonly known for their prolix and heterodox nature, the margins of medieval art present us with a vast array of figures, themes, and representational strategies that deserve to be questioned and learned about. Created to fill voids, to dynamise surfaces and spatial relations, to comment on and amplify the effects anticipated for the centre, they were also invested with playful, prophylactic, and apotropaic functions, so important in medieval culture but still so little studied (and so difficult to study) in Portugal. Among the various protagonists of these margins of medieval art, and particularly from the 13th century on, apes stand out as a satirical and moralising simile of mankind, and, therefore, as the main actors of a topsy-turvy world that finds their natural place in the margins. Attesting to this close relationship, the first known medieval designation for what we now call marginalia, comes from the term babewyn, or baboon, summoning the generality of the simian species and behaviours then known. Based on this affinity, we will seek to identify and, whenever possible, interpret some of the most significant representations of monkeys in medieval marginalia in Portugal during the 14th century, of which two unpublished case studies stand out.

Abstract IE(%) of SCLAE on CR of CS immersed in 1 N HCl was herein assessed by the WL method. The former increased and the latter decreased in the solution with higher Ct of SCLAE. The inhibitor blocked MS corrosion active sites, and created a protective layer that covered its surface. Pc constituents of SCLAE allowed the interaction between their hetero atoms and the metal ions from the CS surface. These Pc were responsible for the CI of CS. Elc studies were herein used to confirm the formation of a protective layer on the CS surface. They were further reinforced by surface analysis techniques, such as FTIR and SEM. EDAX was used to analyze the elements present on the CS surface after its immersion in 1 N HCl without and with SCLAE. Ra of polished, corroded and inhibited CS surfaces was analyzed by SEM and AFM.

ABSTRACT In the food industry, hygiene is a key condition to ensure food safety. That is why this work aimed to describe the visual, microbiological and bioluminescence methods used by food industries to verify sanitation procedures. The methodology was based on the review of the literature in the databases of Google Scholar, Scielo, Latindex, Dialnet, Redalyc and in food regulatory entities. The results showed that the food industries use the different cleaning and disinfection verification methods, either separately or jointly, to achieve compliance with the standards established by the reference regulations. In conclusion, the method used to verify the sanitation procedure resulted from the size of the company, the nature of the food, the processes applied and a series of factors that define the very identity of the industry, to guarantee quality. and food safety.

RESUMEN En la industria alimentaria, la higiene es una condición clave para asegurar la inocuidad de los alimentos. Es por ello, que este trabajo tuvo como objetivo describir sobre los métodos visual, microbiológico y de bioluminiscencia utilizados por las industrias de alimentos para la verificación de los procedimientos de saneado. La metodología se basó en la revisión de la literatura en las bases de datos de Google Académico, Scielo, Latindex, Dialnet, Redalyc y en entes reguladores de alimentos. Los resultados demostraron que las industrias de alimentos utilizan los diferentes métodos de verificación de limpieza y desinfección, ya sea de manera separada o conjunta para lograr cumplir con los estándares establecidos por las normativas de referencia. En conclusión, el método utilizado para la verificación del procedimiento de saneado dependerá de la envergadura de la empresa, la naturaleza del alimento, los procesos aplicados y de una serie de factores que definen la misma identidad de la industria, a fin de garantizar la calidad e inocuidad de los alimentos.

Abstract: This investigation compared the efficiency of a flat-plate solar collector with triangular and square geometry, by using the finite element method (FEM). The design of the geometries and the utilized parameters for the simulation were obtained from previous publications. SolidWorks was used to model the two collectors, meanwhile, the Fluent module of the ANSYS software was used for the simulation by the FEM. Collectors integrated a pipe of 7 mm internal diameter with a plate thickness of 11 mm; the defined material was aluminum. The experiment was conducted under ambient conditions at a temperature of 20 °C, accompanied by a solar radiation intensity of 1000 W·m-2. The heat transfer surfaces employed were 61 250 mm2 for the triangular collector and 122 500 mm2 for the square collector. The quality of the mesh was excellent, obtaining a skewness of 0.2486, with which efficiencies of 62 and 39 % and maximum temperatures of 27 and 25.5 °C were obtained for the triangular and square collectors, respectively. Due to the geometries performing as fins, the temperatures are higher in the corners and, therefore, achieving higher efficiency is impossible.

Resumen: En esta investigación, se comparó la eficiencia de un colector solar de placa plana con geometría triangular y cuadrada, a través del enfoque del método de elementos finitos (FEM, por sus siglas en inglés), se llevó a cabo la simulación. Las geometrías y los parámetros empleados en la simulación fueron extraídos de investigaciones previamente publicadas. Se utilizó el software SolidWorks para el modelado de los dos colectores, mientras que el módulo Fluent del software ANSYS fue utilizado para la simulación por el método FEM. Para los colectores se utilizó una tubería de 7 mm de diámetro interno, con un espesor de placa de 11 mm y de aluminio. Se consideró temperatura ambiente de 20 °C, con una radiación solar de 1000 W·m-2 y superficies de transferencia de calor 61 250 y 122 500 mm2 para el colector triangular y cuadrado, respectivamente. La calidad del mallado fue excelente, alcanzando skewness de 0.2486. De esta manera, luego del proceso de simulación se obtuvo eficiencias de 62 y 39 % y temperaturas máximas de 27 y 25.5 °C para el colector triangular y cuadrado, respectivamente. Debido a que las geometrías actúan como aletas, las temperaturas son más altas en las esquinas y por esto no es posible alcanzar mayor eficiencia.

The influence of solution treatment on the phase evolution and tensile properties of Ti-Mo alloys was investigated to assess their potential use in biomedical applications. Phase formation and microstructural evolution were studied using X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD). The mechanical properties were characterized by means of tensile tests and bending strength. XRD analysis showed that solution treatment increased the volume fraction of ß phase and supressed the α" phase. The microstructures of the as-cast alloys consisted of ß equiaxed grains with sub-grain structures of different sizes, while the solution treated alloys comprised ß equiaxed grains only except for Ti-10.02Mo, which comprised needle-like a" structures. EBSD showed an increase in the volume fraction of the ω and α" phases in all the alloys after solution treatment. The elastic modulus and UTS of all the alloy significantly decreased after solution treatment, except for Ti-15.05Mo, whereas the elongation significantly increased. The fracture surfaces of all the alloys after solution treatment indicated more ductile behaviour than brittle.

Abstract Adsorption behavior of Ca particles obtained from SS, PS and ES calcination, as well as its Td parameters, during A36 MS coating via phosphating process, was investigated. A36 MS coupons surfaces were coated with phosphates and varied C of Ca particles (from 1 to 2.5 g/dm3), at a T of 60 and 80 ºC. Ca particles (as inhibitor) adsorption onto the MS surface obeyed Freundlich’s isotherm, with R2 values around 1. Kads and Td parameters, such as ∆G, ΔH and ΔS, were also determined. A36 MS coated with Ca particles obtained from calcined SS gave the best A capacity, as revealed in terms of Kads, ∆G and ∆S values. Higher Kads was obtained when T increased from 60 to 80 ºC. Also, Td parameters results revealed that Ca particles adsorption mechanism on MS was a more spontaneous process, at an increased T of 80 ºC.

This study investigated the effect of surface roughness on Schmidt rebound hardness (Rl). Four different test surfaces of rock samples were studied: natural, ground, cut surfaces, and core samples. There was significant variability of standard deviation based on the Rl on the natural surface, which indicated high roughness of the rock surface, whereas surface polishing caused a significant decrease in standard deviation. ISRM and ASTM methods were compared to estimate unconfined compressive strength (UCS) for different testing surfaces. Rl obtained from the cut surface was found to be more reliable than those obtained from other testing surfaces for the prediction of UCS; however, regression and ANOVA analyses revealed that the ISRM method gave a more accurate UCS estimation of rocks with highly rough surfaces. It was also shown that Rl values obtained from a cut surface were significantly higher than those obtained from core samples. Therefore, a comparison between Rl values obtained from core samples and cut surfaces was made based on previous studies. This study statistically showed that estimated UCS values are not statistically significant if Schmidt rebound tests are not performed on similar surfaces. In addition, the mineral grain sizes of the studied rocks, different testing surfaces compared with those in literature, and standard deviation from Rl are evaluated and discussed. The Schmidt hammer technique is a rapid, inexpensive, and straightforward method for estimating UCS for preliminary assessment; however, roughness of the surface should be eliminated if variations are shown in the surface rebound hardness.

ABSTRACT The following research presents the calculation of the photovoltaic generation potential from the use of the roof surfaces of buildings for a case study. For this purpose, an energy study was carried out in the facility to identify the demand to be satisfied, and the constructive survey of the building was executed free of shadows that can be used for the mounting of photovoltaic panels considering the dimensions, orientation, and inclination of their roofs, in addition, the specific meteorological information of the territory was obtained, necessary for the generation calculations and its inclusion in the specialized software PVSyst. The PVSyst simulation showed that the company has an available area of 1,317 m2 of building roofs, an area where it is possible to install a total of 510 photovoltaic modules, with a generation capacity of 281 kWp and a real annual generation of 508,416 kWh/year. This photovoltaic installation is capable of covering 102.65 % of the facility's energy demand.

RESUMEN En la siguiente investigación se presenta el cálculo de las potencialidades de generación fotovoltaica a partir del aprovechamiento de las superficies de cubiertas de las edificaciones para un caso de estudio. Para ello se partió de un estudio energético realizado en la instalación con el objetivo de identificar la demanda que se pretende satisfacer y se ejecutó el levantamiento constructivo de la edificación libres de sombra que pueden emplearse para el montaje de paneles fotovoltaicos considerando las dimensiones, orientación e inclinación de sus cubiertas, además se obtuvo la información meteorológica específica del territorio, necesaria para los cálculos de generación y su inclusión en el software especializado PVSyst. La simulación con el PVSyst evidenció que en la empresa existe un área disponible de cubiertas de edificaciones de 1 317 m2, superficie donde es posible instalar un total de 510 módulos fotovoltaicos, con una capacidad de generación de 281 kWp y una generación anual real de 508 416 kWh/año. Dicha instalación fotovoltaica es capaz de cubrir el 102.65% de la demanda energética de la instalación.

Abstract The use of polylactic acid scaffolds has been gaining ground in bone regeneration due to its ability to biodegrade. However, its use in clinical practice is limited, among other aspects, by its low bioactivity. The objective of this work is to evaluate two schemes for the deposition of calcium phosphate coatings on polylactic acid scaffolds made by the Fused Deposition Modeling method. The scaffold surfaces were activated by alkaline treatment in a 0.1M aqueous NaOH solution for 24 h at room temperature. In the deposition of the coatings, a solution supersaturated in calcium ions was used. The two deposition schemes were differentiated by the pH value presented by the solution after the precipitation stage. Nanostructured calcium phosphate deposits of the brushite (scheme 1) and apatite (scheme 2) type were obtained. Deposition scheme 2 generated a greater covered area on the surface of the scaffolds, higher calcium and phosphorus contents and a Ca/P ratio of 1.71 in their agglomerates.

Resumen El uso de andamios de ácido poli láctico ha venido ganando espacio en la regeneración ósea debido a su capacidad de biodegradarse. No obstante, su empleo en la práctica clínica se encuentra limitado, entre otros aspectos, por su escasa bioactividad. El presente trabajo tuvo como objetivo evaluar dos esquemas de deposición de recubrimientos de fosfato de calcio sobre andamios de ácido poliláctico elaborados mediante el método de Modelado por Deposición Fundida. Las superficies de los andamios fueron activadas mediante un tratamiento alcalino en una disolución acuosa al 0,1M de NaOH durante 24 h a temperatura ambiente. En la deposición de los recubrimientos se utilizó una disolución sobresaturada en iones calcio. Los dos esquemas de deposición se diferenciaron por el valor del pH presentado por la disolución después de la etapa de precipitación. Se obtuvieron depósitos de fosfatos de calcio nanoestructurados del tipo brushita (esquema 1) y apatita (esquema 2). El esquema de deposición 2 generó en la superficie de los andamios mayor área recubierta, superiores contenidos de calcio y fósforo y una relación Ca/P de 1,71 en sus aglomerados.

Abstract The purpose of this study was to examine the effect of different decontamination agents on the bond strength of saliva-contaminated CAD/CAM blocks and repair composite materials. Two hunderd eighty 3-mm-thick specimens were prepared from four different CAD/CAM materials: Katana Zirconia UTML disc, IPS e.max CAD block, Shofu block, and Vita Enamic block. Each material was divided into seven different subgroups (N=70). Group 1 had a clean surface. The other groups were comprised of the samples, which were contaminated with human saliva: group 2: negative control (non-cleaned); group 3: cleaned with water spray; group 4: cleaned with 70% ethanol; group 5: cleaned with Ivoclean; group 6: cleaned with Katana Cleaner; and group 7: cleaned with phosphoric acid. After the decontamination protocols, the resin composite cylinders were bonded to the CAD/CAM surfaces with a thin layer of dual-cured resin cement. The samples were stored for 24 hours at 37°C in distilled water. Then, they were subjected to a shear bond strength test (SBS). The values were recorded, and fracture types were evaluated using a microscope. Data were analyzed using two-way ANOVA and Tukey’s post-hoc test. Generally, all decontaminating agents improved the SBS of composites to Katana Zirconia UTML, IPS e.max, and Vita Enamic materials (p<0.05). However, for Shofu materials, group 6 samples exhibited significantly higher bond strength values as compared with group 2 samples (p=0.026). The highest SBS values were seen in the phosphoric acid-treated group in Katana zirconia materials (26.45 ± 9.38 MPa), whereas the lowest values were seen in group 2 samples in Shofu materials (13.17±3.40 MPa). Each decontaminant agent improved the bond strength of composites to the contaminated CAD/CAM materials. If saliva is not cleaned before adhesive procedure, SBS values may decrease. All decontamination agents can be used safely on zirconia, lithium-disilicate glass-ceramic, hybrid ceramic, and polymer-infiltrated ceramic surfaces.

Resumen El propósito de este estudio fue examinar el efecto de diferentes agentes descontaminantes sobre la fuerza de unión de bloques CAD/CAM contaminados con saliva y materiales compuestos de reparación. Se prepararon doscientas ochenta muestras de 3 mm de espesor a partir de cuatro materiales CAD/CAM diferentes: disco Katana Zirconia UTML, bloque IPS e.max CAD, bloque Shofu y bloque Vita Enamic. Cada material se dividió en siete subgrupos diferentes (N=70). El grupo 1 tenía una superficie limpia. Los otros grupos estaban compuestos por muestras que estaban contaminadas con saliva humana: grupo 2: control negativo (no limpio); grupo 3: limpiado con agua pulverizada; grupo 4: limpiado con etanol al 70%; grupo 5: limpiado con Ivoclean; grupo 6: limpiado con Katana Cleaner; y grupo 7: limpiado con ácido fosfórico. Después de los protocolos de descontaminación, los cilindros de composite de resina se adhirieron a las superficies CAD/CAM con una fina capa de cemento de resina de curado dual. Las muestras se almacenaron durante 24 horas a 37°C en agua destilada. Luego, fueron sometidos a una prueba de resistencia al corte (SBS). Se registraron los valores y se evaluaron los tipos de fracturas utilizando un microscopio. Los datos se analizaron mediante ANOVA de dos factores y la prueba post-hoc de Tukey. En general, todos los agentes descontaminantes mejoraron el SBS de los composites con los materiales Katana Zirconia UTML, IPS e.max y Vita Enamic (p<0,05). Sin embargo, para los materiales Shofu, las muestras del grupo 6 exhibieron valores de fuerza de unión significativamente más altos en comparación con las muestras del grupo 2 (p=0,026). Los valores más altos de SBS se observaron en el grupo tratado con ácido fosfórico en materiales de circonio Katana (26,45 ± 9,38 MPa), mientras que los valores más bajos se observaron en las muestras del grupo 2 en materiales Shofu (13,17 ± 3,40 MPa). Cada agente descontaminante mejoró la fuerza de unión de los composites a los materiales CAD/CAM contaminados. Si no se limpia la saliva antes del procedimiento adhesivo, los valores de SBS pueden disminuir. Todos los agentes descontaminantes se pueden utilizar de forma segura en superficies de circonio, cerámica de vidrio de disilicato de litio, cerámica híbrida y cerámica con infiltraciones de polímeros.

Abstract. - The present paper exposes the feasibility of producing particleboards with wastes from the cotton industry in northeastern Argentina, agglomerated with urea-formaldehyde resin, as an alternative to replace wood with lower-cost lignocellulosic waste, for there are no measures to achieve an efficient final disposal. The aim is to achieve particleboards suitable for the construction of housing enclosures and simple furniture. With the intention of optimizing boards behavior, the influence of the particle size distribution and their morphological characteristics on the mechanical properties, water resistance, and final quality of the boards is investigated. Three situations are compared: unclassified milled material, classified milled material, and classified remilled material, which constitutes single-layer boards with resin percentages of 11.9 %, 15.1 %, and 19.3 %. Results show that the use of finer particles increases the flexural strength (MOR) and the modulus of elasticity (MOE) by approximately 35 % compared to boards where larger particles are used. Swelling and water absorption decrease between 25 % and 70 % by using smaller particles. Boards made with smaller particles achieve better resin impregnation and simpler mixing processes, which result in better-cut quality and smoother surfaces. These results contribute to the identification of a final disposal with added value for abundant waste and an alternative raw material that can replace wood in the board manufacturing process.

Resumen. - El presente trabajo expone la posibilidad de generar tableros de partículas con residuos de la industria algodonera del noreste de Argentina, aglomerados con resina urea-formaldehído, como una alternativa de sustitución de la madera por desechos lignocelulósicos de menor costo, para los cuales aún no se han implementado medidas para lograr una disposición final eficiente. Se pretende lograr tableros de partículas que puedan ser utilizados en la construcción de cerramientos de viviendas y mobiliario sencillo. Con la intención de optimizar el comportamiento de estos tableros, se investiga la influencia de la distribución de tamaños de partículas y sus características morfológicas en las propiedades mecánicas, resistencia al agua y calidad final de los tableros. Se comparan tres situaciones: material molido sin clasificar, material molido clasificado y material remolido clasificado, que conforman tableros monocapa con porcentajes de resina de 11,9 %, 15,1 % y 19,3 %. Los resultados muestran que el uso de partículas más finas aumenta aproximadamente un 35% la resistencia a la flexión (MOR) y el módulo de elasticidad (MOE) en comparación con tableros donde se utilizan partículas más grandes. El hinchamiento y la absorción de agua disminuyen entre 25% y 70% utilizando partículas más pequeñas. Los tableros elaborados con partículas más pequeñas logran una mejor impregnación de la resina y procesos de mezclado más sencillos, que redundan en una mejor calidad de corte y superficies más lisas. Estos resultados contribuyen a la identificación de una disposición final de un residuo abundante sumando valor agregado y de alternativas de materias primas que puedan reemplazar a la madera en el proceso de fabricación de tableros.

Resumen La articulación sinovial de la rodilla puede verse afectada por enfermedades, como artritis o artrosis, siendo generalmente el reemplazo de rodilla la solución clínica seleccionada en casos irreversibles. Este trabajo se orienta a investigar el mecanismo de lubricación por aplastamiento en rodillas sanas y artrósicas, con la finalidad de lograr conocimientos que puedan utilizarse para retrasar el reemplazo de rodilla. Se analiza un único cóndilo adoptando el modelo geométrico equivalente de elipsoide rígido sobre plano deformable, donde se considera que el fluido sinovial es Newtoniano y que el cartílago articular es un material elástico lineal. Se realizaron estudios variando el módulo de elasticidad del cartílago, su espesor y la viscosidad del fluido sinovial, adoptando valores correspondientes a articulaciones naturales sanas y osteoartríticas, con el fin de evaluar su influencia en el desempeño del proceso de lubricación por aplastamiento (squeeze film lubrication). En comparación con lo obtenido para una articulación sana, la disminución patológica del módulo de elasticidad no tendría una influencia significativa en el mínimo espesor de película lubricante, mientras que la disminución patológica del espesor del cartílago incrementaría dicho espesor. La disminución patológica de la viscosidad disminuye en un 65 % el espesor mínimo de película lubricante, por lo que la viscosuplementación (y consiguiente aumento de la viscosidad) sería deseable porque prevendría el desgaste de las superficies articulares. La disminución del espesor o en el módulo elástico del cartílago produciría una disminución de las tensiones en el tejido. Por otra parte, una disminución de la viscosidad produce un aumento de estas tensiones. En la articulación artrósica (donde la viscosidad del fluido, el espesor y el módulo elástico del cartílago se encuentran disminuidos), para una carga de 800 N, la altura mínima del canal de lubricación, las presión máxima y la tensión de Von Mises en el cartílago obtenidas son 66%, 22% y 28% menores que aquellas obtenidas para una articulación sana.

Abstrac The synovial joint of the knee can be affected by diseases, such as arthritis or osteoarthritis, being a knee replacement the selected clinical solution in irreversible cases. This work is aimed at investigating lubricated contact in healthy and pathological knees, with the aim of achieving knowledge that can be used to delay knee replacement. The equivalent geometric model of a rigid ellipsoid on a deformable plane is adopted, where the synovial fluid is considered to be Newtonian and the articular cartilage is a linear elastic material. Studies were carried out varying the modulus of elasticity E of the cartilage, its thickness e and the viscosity of the synovial fluid , adopting values corresponding to healthy and osteoarthritic natural joints, in order to evaluate their influence on the functioning of the joint considering squeeze film lubrication. Compared to what was obtained for a healthy joint, the decrease in the elastic modulus E would not have a signifi-cant influence on the minimum lubricant film thickness, while the decrease in cartilage thickness would improve said thickness. The decrease in viscosity decreases the minimum thickness of the lubricating film by 65%, so viscosup-plementation would increase the viscosity, which would also increase said thickness and prevent wear of the articular surfaces. A decrease in cartilage thickness or in cartilage module would produce a decrease of the cartilage tensions. On the other hand, a decrease of viscosity produces an increase of these tensions. In a pathological joint (where the fluid viscosity and the cartilage thickness and elastic module are diminished), and considering a load of 800 N, the minimum film height, the maximum pressure and the maximum Von Mises tension obtained are 66 %, 22% and 28 % respectively lower than those observed for a healthy articulation.

Abstract Gravimetric, electrochemical, surface investigation, RSM and theoretical computational studies, using DFT and MD, were employed to investigate Ecorr inhibition of MS surfaces in 0.5 M H2SO4, by a worm expelling drug (Wormin® MBZ). The results from computational and RSM optimization and experimental methodologies were all in good accord. After 24 h, IE(%) of 1.5 g/L MBZ on MS corrosion, calculated from WL data, was 96.610%. Maximum IE(%) of 1.0 g MBZ was 96.903% (303 K) and 99.998% (333 K). PDP confirmed MBZ mixed nature of adsorption. The impact of the inhibitor C and IT of MS on IE(%) of MBZ was revealed by statistical evaluation and optimization, using Design Expert software package (Stat-Ease). The optimized IE(%) of 96.6103% was obtained with the inhibitor C of 1.061 g/L, at MS 48.58 h IT. On the MS surface, MBZ behaved according to Langmuir’s adsorption isotherm. MD showed that MBZ had an Einteraction of -536.33 and -694.53 kcal/mol, at 303 and 333 K, respectively. Negative Einteraction forecasts confirmed MBZ-MS surface interaction capability, which reinforced the experimental investigations IE(%) findings.