Alkaline pre-treatment (NAOH) as a strategy to increase the performance and feasibility of the anaerobic digestion of cattle slurry.

Dairy cattle manure with bedding (CB), including manure, urine, water, and shavings, is lignocellulosic biomass and needs to be pre-treated in anaerobic reactors to enhance biomass digestibility. This study analyzed the technical and economic feasibility of physical treatment (milling) and alkaline treatment of CB for biogas production. Pre-treatment included drying, milling, and alkaline hydrolysis at room temperature for 24 h. Maximum biogas production was determined using the biochemical methane potential (BMP) test. Physicochemical analyses were performed to characterise CB before and after pre-treatment and the BMP test. The characteristics of the lignocellulosic material were examined by scanning electron microscopy. The economic feasibility (return on investment) of each treatment (USD per ton of CB) was determined. Treatment with 3% NaOH achieved the highest biogas production (771 mL per kg of volatile solids) and was 104.5% higher than that of milling and 124.7% higher than that of chemical pre-treatment with 4% NaOH. The analysis of economic feasibility showed that the payback period of treatment with 3% NaOH was 1.4 years for scenario 1 (continuous stirred tank reactor - CSTR) and 3 years for scenario 2 (covered lagoon digester). These results demonstrate the feasibility of producing biogas as a renewable energy source via the anaerobic digestion of CB.

Prevalencia de la hepatitis B (VHB) en gestantes / Hepatitis B (VHB) prevalence in pregnant women

Se ha realizado un estudio prospectivo transversal en 150 embarazadas en el 3er. trimestre de gestación durante un período de 18 meses, en el Hospital de la Policía Nacional del Perú "Augusto B. Leguía", la determinación del VHB a través del antígeno de superficie (HBsag) y anticuerpo contra el antígeno core de la hepatitis B (anti-HBc). Ambas detecciones se efectuaron con la técnica del enzima-insumo-ensayo (ELISA). Se buscaron datos epidemiológicos y su relación con grupos de alto riesgo. La prevalencia de infección para cualquier marcador de la hepatitis B fué de 4.7 por ciento, de los cuales, 0.7 por ciento correspondió a HBsAg y 4.0 por ciento para Anti-HBc. Se hace hincapié de la medida profiláctica perinatal inmediata para evitar secuelas posteriores.

Síndrome fetal alcoólica / Fetal alcohol syndrome

Estudo baseado em revisäo bibliográfica em que se considera os efeitos do álcool na gravidez e sua expressäo no feto através da SFA. Foram abordadas a fisiopatologia, as manifestaçöes clínicas e o diagnóstico, ressaltando o aspecto da prevençäo

Validade do exame médico de rotina verificada em amostra de escolares da Grande Porto Alegre / Validity of routine medical examination verified in a sample of School form Porto Alegre Suburbs

Relata-se a experiência obtida pelo exame clínico simplificado de uma amostra de 199 escolares de vilas da periferia de Porto Alegre. Constatou-se que 89% das crianças necessitavam algum tipo de assistência médico-sanitária. Säo discutidos os aspectos da validade de tal tipo de investigaçäo pelo estudante de medicina