Tensile behavior of an eutectic Pb–Sn alloy processed by ECAP and rolling

AbstractA eutectic lead–tin alloy was prepared by melting the commercially pure metals and cast in cylindrical molds with 10mm diameter. The billets were processed by 4 passes of ECAP using a die with 90° between channels through route A and rolled to a final thickness of ∼1mm. The microstructure was determined by optical microscopy. Tensile tests were carried out at room temperature in the strain rate range between 10−4 and 10−2s−1. The results show the elongation to failure increases at low strain-rates. The strain-rate sensitivity parameter was determined and a maximum value of ∼0.4 was observed at the lowest strain-rate

Effect of 0.9% saline solution and phosphate buffer saline at different temperatures and incubation times on the morphology of goat preantral follicles

The present work investigated the efficiency of 0.9% saline solution and Phosphate Buffered Saline (PBS) in the preservation of goat preantral follicles in situ at different temperatures and incubation times. The ovarian pair of each animal was divided into 19 fragments. One ovarian fragment was taken randomly and fixed (control). The other 18 fragments were randomly distributed in tubes containing 0.9% saline solution or PBS at 4, 20 or 39 ºC for 4, 12 or 24 h. A total of 5,921 preantral follicles were examined. The quality of preantral follicles was evaluated by classical histology. The storage of ovarian fragments in 0.9% saline solution or PBS at 4 ºC did not reduce significantly the percentage of morphologically normal follicles when compared with the control, except after preservation in 0.9% saline solution for 24 h. The storage of ovarian fragments at 20 or 39°C reduced the percentage of normal preantral follicles when compared to the control, except after preservation in PBS at 20°C for 4 h. In conclusion, this study showed for the first time that goat preantral follicles can be stored in situ successfully at 4 ºC in 0.9% saline solution for 12 h and in PBS for 24 h, and at 20 ºC in PBS for 4 h.O presente trabalho investigou a eficiência da solução salina 0,9% e tampão fosfato salina (PBS) na conservação de folículos pré-antrais caprinos in situ a diferentes temperaturas e tempos de incubação. O par ovariano de cada animal foi dividido em 19 fragmentos. Um fragmento foi escolhido aleatoriamente e fixado (controle). Os outros 18 fragmentos foram distribuídos aleatoriamente em tubos contendo solução salina 0,9% ou PBS a 4, 20 ou 39 °C por 4, 12 ou 24 h. Um total de 5.921 folículos pré-antrais foram analisados. A qualidade dos folículos pré-antrais foi avaliada através de histologia clássica. A incubação de fragmentos ovarianos em solução salina 0,9% ou PBS a 4 ºC não reduziu significativamente a percentagem de folículos morfologicamente normais quando comparados com o controle, exceto após a conservação em solução salina 0,9% por 24 h. A incubação de fragmentos ovarianos a 20 ou 39°C reduziu a percentagem de folículos pré-antrais normais quando comparados com o controle, exceto após conservação em PBS a 20°C por 4 h. Em conclusão, este estudo mostrou pela primeira vez que folículos pré-antrais caprinos podem ser conservados in situ com sucesso a 4 ºC em solução salina 0,9% por 12 h e em PBS por 24 h, e a 20 ºC em PBS por 4 h

Microstructure and hardness of cement pastes with mineral admixture

Portland cement pastes are highly heterogeneous material and exhibits heterogeneous features over a widerange of length scales. Mechanical properties of microstructure can be determined using depth-sensing indentation.Coupled indentation/SEM technique can be used to location the indents and provides a way to determinethe mechanical properties of a specific phase. Thus, the present paper aims to determine the hardness ofdifferent phases of cement pastes prepared with different mineral admixtures including sugarcane bagasseash. The microstructure of cement pastes prepared with different mineral admixtures is analyzed by X raydiffraction, scanning electron microscopy and dynamic hardness tests on polished sections. The differentbackscatter coefficient allows to differentiate anhydrous phases from C-S-H, calcium hydroxide, silica fumeand quartz. A grid of indentation is used to determine the hardness of the different phases and a completephase segmentation of the different samples is achieved. The results show that the hardness of the differentphases follow the sequence (from higher to lower hardness) quartz, anhydrous particles, calcium hydroxide,C-S-H and agglomerated silica fume. The presence of agglomerated silica fume is clearly observed in scanningelectron microscopy images and the poor mechanical properties of these areas might compromise thecement pastes. The microstructure of cement pastes prepared with sugarcane bagasse ashes is similar to theobserved in samples with crushed quartz

Activities and mechanisms of oregano, marjoram and rosemary essential oils against Malassezia pachydermatitis isolates from canine and feline otitis

Malassezia pachydermatis is an opportunistic yeast found in the ear canal of small animals; however, the current azole-based therapy applied to it has failed to achieve clinical success due to the antifungal resistance. This issue has encouraged the studies in natural products, such as Origanum vulgare (oregano), Origanum majorana (marjoram) and Rosmarinus officinalis (rosemary) essential oils, although their mechanism of action remains unclear. Malassezia pachydermatis specimens deriving from otitis cases in dogs (n = 22) and cats (n = 2) were subjected to CLSI M27-A3. Sorbitol protection and ergosterol effect were analyzed to investigate their mechanism of action. Fungistatic (MIC) and fungicidal (MFC) activities were observed for oregano (MIC90/MFC90: 0.625 mg/mL); marjoram (MIC90/MFC90: 2.5 mg/mL) and rosemary MIC90/MFC90 > 2.5 mg/mL). Oregano showed superior antifungal effect even at lower MIC and MFC values. All three oils acted on cell wall and at complexation to fungal ergosterol. By gas chromatography (GC-FID), carvacrol was the major compound found in oregano (73.9%); 1,8-cineole was for marjoram and rosemary (20.9% and 49.4%, respectively). These findings support the potential use of these essential oils to treat canine and feline otitis caused by Malassezia pachydermatis

Influência da expressão e educação físico motora no desenvolvimento da criança do 1º ciclo do ensino básico : contextos, perspetivas e participantes

A formação global da criança, na qual se integra a formação motora, deve ocupar um lugar de relevância na escola atual. Neste espaço, os alunos constroem o seu próprio conhecimento, e ao vivenciarem as aprendizagens de forma lúdica, potenciam o desenvolvimento de outras competências. O presente Relatório Final de Estágio encontra-se dividido em duas partes distintas: as reflexões críticas das práticas em contexto e o trabalho de investigação. Na primeira parte é apresentada uma apreciação crítica das práticas em contexto prático, nomeadamente na educação pré-escolar e do ensino do 1.º CEB. Na segunda parte damos a conhecer o trabalho de investigação, baseado num estudo de natureza quantitativa realizado no contexto de 1.º CEB de um Agrupamento de Escolas de Aveiro e de um Agrupamento de Escolas de Viseu que visa compreender a influência da Expressão e Educação Físico-Motora no desenvolvimento global da criança. Para o efeito, recorremos a autores de referência e à legislação em vigor, assim como, em termos empíricos, as respostas aos questionários dirigidos aos professoras do 1.º CEB. Os resultados encontrados apontam para o seguinte conjunto de principais conclusões: 1.º os professores atribuem muita importância às práticas motoras, constituindo-se como um fator fundamental para o desenvolvimento integral e harmonioso da criança; 2.º a Expressão e Educação Físico-Motora não têm sido uma realidade nas escolas do estudo, os professores apresentam como principais causas: a falta de condições de materiais, espaciais e de equipamentos como também a necessidade de formação, quer a nível da formação inicial quer a nível da formação contínua; 3.º os agrupamentos, as escolas e os professores devem estar implicados nos diferentes contextos nos quais circula a criança e que são promotores de formação e desenvolvimento, tanto ao nível dos quadros letivos e curriculares como também nos de enriquecimento curricular e nos projetos mais lúdicos e de recreação; 4.º a Expressão e Educação Físico-Motora deve assumir claramente o seu carácter formativo, onde a iniciativa e responsabilidade na organização deve ir ao encontro das aspirações das crianças e de toda a comunidade educativa.The overall formation of the child, in which the motor formation is integrated, must occupy a place of relevance in the present school. In this space, students construct their own knowledge, and when they experience learning in a playful way, they foster the development of other skills. This Final Internship Report is divided into two distinct parts: the critical reflections of the practices and the research work. The first part presents a critical appraisal of practices in a practical context, namely in pre-school education and 1st cycle education (1st CEB). In the second part it is presented the research work, based on a quantitative study carried out in the context of 1st CEB in two schools from Aveiro and Viseu Portuguese Grouping of Schools that aims to understand the influence of physical-motor expression in the overall development of the child. To this end, authors of reference and legislation in force, as well as, in empirical terms, the answers to the questionnaires addressed to the teachers of the 1st CEB were used as methodology to reach the desirable goal. The results lead to the following set of main conclusions: 1) teachers attach great importance to motor practices, constituting as a fundamental factor for the integral and harmonious development of the child; 2) physical-motor expression have not been a reality in the schools of the study, the main causes of teachers are: the lack of material, space and equipment conditions as well as the need for training, both in training Initial or continuing training; 3) groups, schools and teachers must be involved in the different contexts in which the child circulates and are promoters of training and development, both in terms of school and curricular frameworks as well as curriculum enrichment and more playful projects and recreation; 4) expression and physical-motor education must clearly assume its formative character, where the initiative and responsibility in the organization must meet the aspirations of the children and the entire educational community

Os aspectos semiológicos do acidente vascular encefálico: uma abordagem neurológica

O Acidente Vascular Encefálico (AVC) é um evento neurológico súbito, com um foco de isquemia ou hemorragia. Ambos, qualificados pelo déficit neurológico focal abrupto. Ressaltando, que estes déficits podem ocorrer, sendo a ocorrência espontânea, perduração de 15 minutos, autoresolutiva é denominada como Ataque Isquêmico Transitório (AIT), no entanto, toda insuficiência neural que não melhorar pós esse período deve ser manejado como AVC. O artigo objetivou descrever os principais aspectos clínicos do AVC. O AVC é uma emergência para a saúde pública, em razão de ser um potencial em gerar morbimortalidades para os portadores e prejuízos para os sistemas de saúde. O AVC do tipo isquêmico representa a maioria das ocorrências, o quadro clínico do paciente é correspondente ao tecido neural afetado, inicialmente a tomografia computadorizada sem contraste é o primeiro exame, por ser crucial para descartar a etiologia hemorrágica, a condução terapêutica se baseia em medidas neuroprotetoras através da estabilização da glicemia, temperatura e sódio, adequar os níveis pressóricos, mediante o prazo estipulado impor terapia antitrombótica. A manifestação hemorrágica, pode ocorrer por torção de aneurisma sacular originando o sangramento subaracnóideo ou por hipertensão gerando o sangramento intraparenquimatoso. A partir da análise das informações coletadas, elucida-se que o diagnóstico precoce e o período transcorrido até o manejo terapêutico são cruciais para o desfecho clínico do portador, ou seja, é possível a normalização ou ocorrer sequelas neurais e óbito

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men