Characterisation of mechanical and thermal properties in flax fabric reinforced geopolymer composites

This paper presents the mechanical and thermal properties of flax fabric reinforced fly ash based geopolymer composites. Geopolymer composites reinforced with 2.4, 3.0 and 4.1 wt% woven flax fabric in various layers were fabricated using a hand lay-up technique and tested for mechanical properties such as flexural strength, flexural modulus, compressive strength, hardness, and fracture toughness. All mechanical properties were improved by increasing the flax fibre contents, and showed superior mechanical properties over a pure geopolymer matrix. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) studies were carried out to evaluate the composition and fracture surfaces of geopolymer and geopolymer/flax composites. The thermal behaviour of composites was studied by thermogravimetric analysis (TGA) and the results showed significant degradation of flax fibres at 300 °C

Biochemical characterization and low-resolution SAXS shape of a novel GH11 exo-1,4-β-xylanase identified in a microbial consortium

Biotechnologies that aim to produce renewable fuels, chemicals, and bioproducts from residual ligno(hemi)cellulosic biomass mostly rely on enzymatic depolymerization of plant cell walls (PCW). This process requires an arsenal of diverse enzymes, including xylanases, which synergistically act on the hemicellulose, reducing the long and complex xylan chains to oligomers and simple sugars. Thus, xylanases play a crucial role in PCW depolymerization. Until recently, the largest xylanase family, glycoside hydrolase family 11 (GH11) has been exclusively represented by endo-catalytic β-1,4- and β-1,3-xylanases. Analysis of a metatranscriptome library from a microbial lignocellulose community resulted in the identification of an unusual exo-acting GH11 β-1,4-xylanase (MetXyn11). Detailed characterization has been performed on recombinant MetXyn11 including determination of its low-resolution small angle Xray scattering (SAXS) molecular envelope in solution. Our results reveal that MetXyn11 is a monomeric globular enzyme that liberates xylobiose from heteroxylans as the only product. MetXyn11 has an optimal activity in a pH range from 6 to 9 and an optimal temperature of 50 oC. The enzyme maintained above 65% of its original activity in the pH range 5 to 6 after being incubated for 72 h at 50 oC. Addition of the enzyme to a commercial enzymatic cocktail (CelicCtec3) promoted a significant increase of enzymatic hydrolysis yields of hydrothermally pretreated sugarcane bagasse (16% after 24 h of hydrolysis)

Christmas Economics - A Sleigh Ride

Do you believe that at Christmas time the gas prices, the economy and the number of suicides peak? Do you think that the value of presents you are giving to your beloved is of importance? We show in this paper that conventional wisdom about Christmas is often doubtful. Furthermore, we give an idea of how Santa Claus - and maybe you - is able to finance Christmas celebrations, why emergency departments are a place to especially avoid during this time of the year and why Christmas tree growers might care to explain the differences across species to you this year. We cannot clearly establish whether Christmas entails a welfare loss or gain, however, we give you an idea as to which institutional settings might reduce a potential welfare loss. Also, we give advice about which behaviours might get you more Christmas presents from Santa this year. Finally, we find that more research is needed to give conclusive reasons why Santa Claus actually brings presents to (nearly) everyone

The Private Files S?o Caetano : registry(s) itself, constitution memories and writing of History.

Programa de P?s-Gradua??o em Hist?ria. Departamento de Hist?ria, Instituto de Ci?ncias Humanas e Sociais, Universidade Federal de Ouro Preto.Esta disserta??o se prop?e a discutir o processo de constitui??o, defini??o e uso dos arquivos privados, considerando o processo da escrita de si enquanto pr?ticas dos indiv?duos que se constitui em ferramentas na constru??o de mem?rias dos sujeitos titulares e da escrita da Hist?ria. Por tr?s deste ac?mulo existe nos indiv?duos uma vontade de registrar e preservar suas trajet?rias, condicionada por sensibilidades e anseios de representa??o. Tendo como campo de an?lise a documenta??o presente no Arquivo Privado S?o Caetano, iremos explorar especialmente os registros de um dos membros da fam?lia Ferreira Ramos, Arlindo Agostinho Ramos. Por meio da escrita epistolar e de outros registros acumulados por Arlindo, apreendemos express?es de intimidade deste titular, o modo pelo qual compreendia e registrava o mundo ao seu redor, assim como as redes de sociabilidade que se entrela?aram no decorrer de sua vida.This dissertation aims to discuss the process of constitution, definition and use of private archives. It has considered the writing process itself, practices of individuals that constitutes tools in building memories of the subject holders and writing of history. Behind these data, there are individuals who desire to Record, and preserve their trajectories expressing deep feelings and concerns about this representation. Focusing on present data at the Archive Private S?o Caetano, we Will particularly explore personal records of one member of the Ferreira Ramos family, called Arlindo Agostinho Ramos. Through the epistolary writing and other records compiled by Arlindo, we have seen how he does Record his expressions and intimacy. The particular way how he registered facts around his family?s life is trying to be understood by us, as well as the social networks that laced up throughout his life

Ventiloterapia domiciliária em doentes com insuficiência respiratória crónica

RESUMO: Introdução: A ventilação por pressão positiva via nasal tem-se tornado o método de escolha da assistência ventilatória domiciliária, sendo eficaz na maioria dos doentes com lnsuficiência Respiratória Crónica (IRC).Objectivo: Analisar a experiência com a Ventiloterapia Domiciliária (VD) e avaliar a sua eficácia no tratamento de doentes com IRC de várias etiologias.Material e métodos: lniciámos VD em 21 doentes (8 M/13H), com média de idades de 58.3±11 anos, PaO2 58±8.9 mmHg, PaCO2 59±10 mmHg, pH 7.38±0.05, FEVI (%) 56.6±28.6, FVC (%) 62.2±26.2, IT 73.3±15.5. Do grupo estudado, 11 tinham Síndrome de Hipoventila­ção/Obesidade, 4 Cifoscoliose, 3 Toracoplastia/Sequelas de TP e 3 DPOC/αSíndrome de Overlap». Em 11 doentes a instituição da terapeutica foi feita em fase aguda e 3 foram excluídos da análise (1 não tolerou o tratamento e 2 mudaram de residência). Em todos os casos usou-se o BiPAP por via nasal (5 comO2 associado), excepto em 3 que utilizaram CPAP.Resultados: O tempo de utilização médio diário do ventilador foi de 6.7±3.4 horas aos 3 meses e de 7±3.5 horns aos 6 meses. Nos 16 doentes com reava li ação aos 3 meses a PaO2 aumentou para 68.8±16.9 mmHg (p<0.02), a PaCO2 caiu para 52.4±8.8 mmHg (p<0.005). Aos 6 meses, a PaO2 mantinha-se significativamente mais elevada em relação ao valor basal (PaO1 70.5±1 5 mmHg; p<0.02), enquanto que a PaCO2 descia de modo mais significativo (PaCO2 48.7±7 mmHg; p<0.002). Para além da melhoria subjectiva em todos os doentes, verificámos uma redução significativa do número de dias de internamento e de ventilação mecânica após o início da VD (51.3±82.4 dias de internamento versus 1±4, p<0.0005; 16.3±47.9 dias de ventilação mecânica versus 0, p<0.02).Conclusão: Na nossa experiância, a VD por pressão positiva via nasal é um tratamento eficaz no controle da falância ventilatória. A boa tolerância e aderência associadas à redução dos custos por admissões hospital ares, aconselham a sua utilização oeste contexto. ABSTRACT: Introduction: Nasal positive pressure ventilation has become the method of choice for domiciliary ventilatory assistance, with efficacy in the majority of patients with Chronic Respiratory Failure (CRF).Aim: Analise the experience with Domiciliary Ventilation (DV) and evaluate its eficacy in the treatment of patients with CRF of different etiologies.Patients and Methods: We have started DV in 2 1 patients (8 F/13 M), mean age 58±11 years, PaO2 58±8.9 mmHg, paCO2 59±10 mmHg, pH 7.38±0.05, FEVI%56.6±28.6, FVC%62.2±26.2, FEVI/FVC 73.3±15.5. The study group comprised 11 patients with Obesity-Hypoventilation Syndrome, 4 with Kyphoscoliosis, 3 Sequelae of Tuberculosis/Thoracoplasty and 3 COPD/Overlap Syndrome. In 11 patient initiation of ventilation was done during acute phase and 3 cases were excluded from analysis (I did not tolerate therapy and 2 changed dwelling). In all cases nasal BiPAP was used (5 with O2), except three that were on CPAP.Results: Mean duration of daily ventilator use was 6. 7±3.4 hours at 3 months and 7±3.5 horas at 6 months. In 16 patients with 3 months follow-up PaO2 rose to 68.8±16.9 mmHg (p<0.02; Wilcoxon test), PaCO2 dropped to 52.4±8.8 mmHg (p<0.005). At 6 months PaO2 was still significantly higher than its initial level (PaO2 70.5±1 5 mmHg; p<0.02), while PaCO2 dropped more significantly (PaCO2 48. 7±7 mmHg; p<0.002). Besides subjective improvement in all patients, we found a significant reduction in hospitalization duration and days of mechanical ventilation after DV was started (51.3±82.4 hospital days versus 1±4, p<0.0005; 16.3±47.9 days of mechanical ventilation versus 0, p<0.02).Conclusions: In our experience, nasal positive pressure DV is an effective treatment in the control of ventilatory failure. Both good tolerance and compliance together with reduction in hospital costs, support its use in this context. Palavras-chave: Ventiloterapia dom1ciliária, ventilação não-invasiva, insuficiência respiratória crónica, sindrome de hipoventilação-obesidade, Key-words: Domiciliary ventilationnon-mvas1ve ventilation, restrictive disorders, obesity-hypoventilation syndrom