Single Lap Joints Numerical Modelling and Comparison with Experimental Testing

Adhesive bonding is a joining technique which has been extensively employed in structural design as its ability to join different types of materials allows higher freedom for designers when choosing materials. One of the most common joint configuration used is the single lap joint configuration. In this work a set of experimental procedures were undertaken to characterize a structural adhesive and model the behaviour of a single lap joint manufactured using this adhesive. Two types of surface preparations were used to study its effect in single lap joint strength

Sensibilidad de la microestructura en un sistema multi-escala

Este trabajo analiza la sensibilidad de los parámetros de optimización de una microestructura periódica isotrópica en la optimización topológica de una viga MBB. La función objetivo para optimización de la microestructura es el módulo volumétrico, y los parámetros analizados son: fracción volumétrica, radio de filtro y factor de penalización. En la macroestructura la función objetivo es la minimización de la flexibilidad, sujeta a un volumen predefinido de 0.5. Se desarrolló un algoritmo, con base en el método SIMP, capaz de transferir las informaciones de la microestructura para la macroestructura. Se realizaron análisis numéricos, variando los parámetros y observando el comportamiento de las soluciones. Los resultados demuestran que la fracción volumétrica de la microestructura tiene gran influencia en la maximización de la rigidez, sin embargo el radio de filtro y el factor de penalización presentaron poca influencia, así como sobre el perfil de la macroestructura.Publicado en: Mecánica Computacional vol. XXXV, no. 23Facultad de Ingenierí

Sensibilidad de la microestructura en un sistema multi-escala

Este trabajo analiza la sensibilidad de los parámetros de optimización de una microestructura periódica isotrópica en la optimización topológica de una viga MBB. La función objetivo para optimización de la microestructura es el módulo volumétrico, y los parámetros analizados son: fracción volumétrica, radio de filtro y factor de penalización. En la macroestructura la función objetivo es la minimización de la flexibilidad, sujeta a un volumen predefinido de 0.5. Se desarrolló un algoritmo, con base en el método SIMP, capaz de transferir las informaciones de la microestructura para la macroestructura. Se realizaron análisis numéricos, variando los parámetros y observando el comportamiento de las soluciones. Los resultados demuestran que la fracción volumétrica de la microestructura tiene gran influencia en la maximización de la rigidez, sin embargo el radio de filtro y el factor de penalización presentaron poca influencia, así como sobre el perfil de la macroestructura.Publicado en: Mecánica Computacional vol. XXXV, no. 23Facultad de Ingenierí

Sensibilidad de la microestructura en un sistema multi-escala

Este trabajo analiza la sensibilidad de los parámetros de optimización de una microestructura periódica isotrópica en la optimización topológica de una viga MBB. La función objetivo para optimización de la microestructura es el módulo volumétrico, y los parámetros analizados son: fracción volumétrica, radio de filtro y factor de penalización. En la macroestructura la función objetivo es la minimización de la flexibilidad, sujeta a un volumen predefinido de 0.5. Se desarrolló un algoritmo, con base en el método SIMP, capaz de transferir las informaciones de la microestructura para la macroestructura. Se realizaron análisis numéricos, variando los parámetros y observando el comportamiento de las soluciones. Los resultados demuestran que la fracción volumétrica de la microestructura tiene gran influencia en la maximización de la rigidez, sin embargo el radio de filtro y el factor de penalización presentaron poca influencia, así como sobre el perfil de la macroestructura.Publicado en: Mecánica Computacional vol. XXXV, no. 23Facultad de Ingenierí

Identification by MALDI-TOF MS of Sporothrix brasiliensis isolated from a subconjunctival infiltrative lesion in an immunocompetent patient

Sporotrichosis is a globally distributed subcutaneous fungal infection caused by dimorphic fungi belonging to the Sporothrix species complex that affects the skin of limbs predominantly, but not exclusively. A rare case of ocular sporotrichosis in an immunocompetent Brazilian patient from the countryside of Rio de Janeiro State is reported. A 68-year-old woman presented with a subconjunctival infiltrative lesion in the right eye with pre-auricular lymphadenopathy of onset 4 months ago that evolved to suppurative nodular lesions on the eyelids. Conjunctival secretion was evaluated by histopathological examination and inoculated on Sabouraud Dextrose Agar (SDA). Histopathology showed oval bodies within giant cells and other mononucleated histiocytes. Fungus grown on SDA was identified as Sporothrix sp. by morphological observations. The isolated strain was finally identified by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) associated with an in-house database enriched with reference Sporothrix complex spectra. The strain presented a MALDI spectrum with the ion peaks of the molecular mass profile of S. brasiliensis. The patient was adequately treated with amphotericin B subsequently replaced by itraconazole. Due to scars left by the suppurative process, the patient presented poor final visual acuity. The present work presents an overview of ocular sporotrichosis and discusses the diagnostic difficulty that can lead to visual sequelae in these cases.Financial support for this work by Fundação de Amparo à Pesquisa do Rio de Janeiro [FAPERJ] (Grants: INST E-26/010.001784/2016; JCNE E-26/203.301/2017), by Conselho Nacional de Desenvolvimento Científico e Tecnológico [CNPq] (Grant Proc. 409227/2016-1). This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES). MALDI-TOF MS analyses were partially developed using equipment funded by CONICYT/Chile through the project Fondequip EQM160054 2016. The Universidad de La Frontera (Temuco, Chile) partially funded this work through the Project DIUFRO PIA19-0001. Furthermore, this study was also supported by FCT under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Characterization of Blood Oxidative Stress in Type 2 Diabetes Mellitus Patients: Increase in Lipid Peroxidation and SOD Activity

This study evaluated the oxidative stress through enzymatic and nonenzymatic biomarkers in diabetic patients with and without hypertension and prediabetics. The SOD and CAT (in erythrocytes) and GPx (in plasma) enzymatic activities, plasma levels of lipid peroxidation, and total thiols were measured in the blood of 55 subjects with type 2 diabetes and 38 subjects without diabetes (9 pre-diabetics and 29 controls) aged 40–86 years. The total SOD activity and the lipid peroxidation were higher in diabetics compared to nondiabetics. In stratified groups, the total SOD activity was different for the hypertensive diabetics compared to the prediabetics and normotensive controls. Lipid peroxidation was significantly higher in both groups of diabetics (hypertensive and normotensive) compared to prediabetic groups and hypertensive and normotensive controls. There was no significant difference in the CAT and GPx activities, as well as in the concentration of total thiols in the groups studied. Present data strongly suggest the involvement of oxidative stress in the pathophysiology of diabetes, revealing that the increased lipid peroxidation has a close relationship with high glucose levels, as observed by the fasting glucose and HbA1c levels. The results evidence the correlation between lipid peroxidation and DM, irrespective of the presence of hypertension

Genetic diversity and structure of two species of Enyalius (Squamata: Leiosauridae) from neotropical biodiversity hotspots

Diversidade e estrutura genética de duas espécies de Enyalius (Squamata: Leiosauridae) em hotspots neotropicais de biodiversidade. Os lagartos do gênero Enyalius são endêmicos da América do Sul, sendo predominantemente encontrados no Cerrado e em fragmentos da Floresta Atlântica. Este é um gênero pouco estudado, e não foram encontrados dados relacionados à diversidade e à estrutura genética das espécies do gênero. Neste trabalho, investigamos a diversidade genética de populações de E. bilineatus (N = 20) e E. perditus (N = 28), usando um fragmento de 234-pb do citocromo b, e comparamos as sequências geradas com outras publicadas. Dezenove haplótipos distintos foram encontrados (11 de E. perditus e oito de E. bilineatus), sendo oito deles novos registros. Os valores de diversidade haplotípica foram muito similares para as duas espécies (0.684 para E. perditus e 0.647 para E. bilineatus). A distância genética entre as duas espécies foi de 20.3%, e as distâncias intraespecíficas foram 2.0% para E. perditus e 5.6% para E. bilineatus. Nossos dados sugerem que as populações de E. bilineatus são altamente divergentes e que a espécie deve apresentar diversidade críptica. Este é o primeiro estudo medindo a diversidade genética de espécies do gênero Enyalius oriundas de regiões consideradas hotspots da biodiversidade neotropical e apresenta dados relevantes para um melhor entendimento das relações inter e intrapopulacionais, assim como a distribuição das linhagens genéticas desse gênero endêmico.Genetic diversity and structure of two species of Enyalius (Squamata: Leiosauridae) from neotropical biodiversity hotspots. Enyalius, a lizard genus endemic to South America, is mostly distributed in the remains of the Atlantic Forest and in the Cerrado. The genus has been the topic of a few studies but none has quantified the genetic diversity and structure within and among populations of Enyalius. The genetic diversity and structure of populations of E. bilineatus (N = 20) and E. perditus (N = 28) are examined using a 234-bp fragment of the cytochrome b gene and compared with the sequences reported in other published data. Nineteen distinct haplotypes (eleven for E. perditus and eight for E. bilineatus) were found, eight of which were recorded for the first time. The haplotype diversities are highly similar for both species (0.684 for E. perditus and 0.647 for E. bilineatus). The genetic distance between the two species is 20.3% and the distance within species is 2.0% and 5.6% for E. perditus and E. bilineatus, respectively. Our data suggest that populations of E. bilineatus are genetically divergent and may reveal cryptic diversity. This is the first study to quantify the genetic diversity of species of Enyalius from Neotropical biodiversity hotspots. These data facilitate a better understanding of both within and among population variation, and highlight the distribution of genetic lineages of an endemic and poorly studied genus

Modelling the Radiative Effects of Biomass Burning Aerosols on Carbon Fluxes in the Amazon Region

Every year, a dense smoke haze covers a large portion of South America originating from fires in the Amazon Basin and central parts of Brazil during the dry/biomass-burning season between August and October. Over a large portion of South America, the average aerosol optical depth at 550 nm exceeds 1.0 during the fire season while the background value during the rainy season is below 0.2. Biomass burning aerosol particles increase scattering and absorption of the incident solar radiation. The regional-scale aerosol layer reduces the amount of solar energy reaching the surface, cools the near surface air, and increases the diffuse radiation fraction over a large disturbed area of the Amazon rainforest. These factors affect the energy and CO2 fluxes at the surface. In this work, we applied a fully integrated atmospheric model to assess the impact of biomass burning aerosols in CO2 fluxes in the Amazon region during 2010. We address the effects of the attenuation of the global solar radiation and the enhancement of the diffuse solar radiation flux inside the vegetation canopy. Our results indicate that the biomass burning aerosols led to increases of about 27% of gross primary productivity of Amazonia, 10% of plant respiration and a decline in soil respiration of 3%. Consequently, in our model Amazonia, became a net carbon sink; net ecosystem exchange during September 2010 dropped from +101 to -104 TgC when the aerosol effects are considered, mainly due to the aerosol diffuse radiation effect. For the forest biome, our results point to a dominance of the diffuse radiation effect on CO2 fluxes, reaching a balance of 50% - 50% between the diffuse and direct aerosol effects for high aerosol loads. For C3 grasses and Savanna (cerrado), as expected, the contribution of the diffuse radiation effect is much lower, tending to zero with the increase of aerosol load. Taking all biomes together, our model shows the Amazon during the dry season, in the presence of high biomass burning aerosol loads, changing from being a source to being a sink of CO2 to the atmosphere