The Aspergillus niger faeB gene encodes a second feruloyl esterase involved in pectin and xylan degradation and is specifically induced in the presence of aromatic compounds

The faeB gene encoding a second feruloyl esterase from Aspergillus niger has been cloned and characterized. It consists of an open reading frame of 1644 bp containing one intron. The gene encodes a protein of 521 amino acids that has sequence similarity to that of an Aspergillus oryzae tannase. However, the encoded enzyme, feruloyl esterase B (FAEB), does not have tannase activity. Comparison of the physical characteristics and substrate specificity of FAEB with those of a cinnamoyl esterase from A. niger [Kroon, Faulds and Williamson (1996) Biotechnol. Appl. Biochem. 23, 255-262] suggests that they are in fact the same enzyme. The expression of faeB is specifically induced in the presence of certain aromatic compounds, but not in the presence of other constituents present in plant-cell-wall polysaccharides such as arabinoxylan or pectin. The expression profile of faeB in the presence of aromatic compounds was compared with the expression of A. niger faeA, encoding feruloyl esterase A (FAEA), and A. niger bphA, the gene encoding a benzoate-p-hydroxylase. All three genes have different subsets of aromatic compounds that induce their expression, indicating the presence of different transcription activating systems in A. niger that respond to aromatic compounds. Comparison of the activity of FAEA and FAEB on sugar-beet pectin and wheat arabinoxylan demonstrated that they are both involved in the degradation of both polysaccharides, but have opposite preferences for these substrates. FAEA is more active than FAEB towards wheat arabinoxylan, whereas FAEB is more active than FAEA towards sugar-beet pectin

Rethinking Workers' Education in Africa

The employment patterns and trends as well as technological changes have been the most important factors in broadening the need to rethink workers' education in Africa. Workers' education more than before, now has a particularly critical role to play in the various Africa rapidly changing societies by providing knowledge and information that the working class people need in order to cope with the changing conditions. Obviously, the role of workers' education in Africa assumes greater and greater importance. Wide ranges of capabilities are required nowadays to deal with emerging technological challenges. This shift of emphasis involved in looking at 'wider education' or 'development education' for increased sociooolitical and economic roles rather than 'education for industry' or 'technical utilitarian education', immediately makes it clear that the task is vast and challenging, requiring a new perspective. It is on this basis, that this paper therefore attempts the possibility of rethinking workers' education as constituting the most important form of human capital formation in African countries. Thus a rejuvenated, complicated, comprehensive and highly integrated facet of workers' education is seen as a key factor in creating an African labour force that will be able to play an effective role in the development of the various African nations

Edible films based on aqueous emulsions of low-methoxyl pectin with recovered and purified sunflower waxes

BACKGROUND: Edible films were obtained from aqueous emulsions prepared with low-methoxyl pectin at different concentrations (10, 20 and 30 g kg−1) and two sunflower wax samples recovered from two waste samples of filter cakes produced in the winterization process of sunflower oil. The two sunflower waxes samples recovered (from the normal hybrid, NSFW, and from the high-oleic hybrid, HOSFW) were added in three proportions (0.1, 0.2 and 0.3 g g-1 of pectin). Films were evaluated according to their structure, water resistance, water vapor permeability, mechanical properties and thermal behavior. RESULTS: In general, good dispersion of the lipid material was observed in the cross-sections of the film. Increase in the water resistance (lower swelling index and water adsorption) was associated with a greater pectin content crosslinked with Ca2+ and the hydrophobic nature of waxes. The reduction in water vapor transfer rates was influenced by the effect of the wax addition, their fatty acid composition and their good distribution on the film. More resistant, rigid and less flexible films were obtained with lower pectin content, finding an inverse relationship between tensile strength and elongation percentage values. CONCLUSION: These results evidence a promising alternative in the development of innovative strategies to valorize sunflower waxes derived from waste material.Fil: Chalapud Narvaez, Mayra Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Baumler, Erica Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ingeniería Química; ArgentinaFil: Carelli Albarracin, Amalia Antonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ingeniería Química; Argentin

До історії становлення прогнозо-аналітичних досліджень науково-технологічного розвитку в Центрі досліджень науково-технічного потенціалу та історії науки ім. Г.М. Доброва НАН України

Висвітлено внесок Г.М.Доброва у становлення прогнозно-аналітичних досліджень перспектив розвитку науки і технологій в Україні та роботу, яка виконується в Центрі досліджень науково-технічного потенціалу та історії науки ім. Г.М.Доброва НАН України з такого прогнозування в сучасний період.Освещены вклад Г.М.Доброва в становление прогнозно-аналитических исследований перспектив развития науки и технологий в Украине и работа, выполненная в Центре исследований научно-технического потенциала и истории науки им.Г.М.Доброва НАН Украины по такому прогнозированию в современный период.The contribution by D.M.Dobrov in establishment of prognosticating and analytical studies of science and technologies in Ukraine is shown, along with relevant works performed in G.M.Dobrov Center for Science and Technology Potential and Science History Studies of the NAS of Ukraine in the current period

Benchmark Forecasts for Climate Change

We assessed three important criteria of forecastability—simplicity, certainty, and variability. Climate is complex due to many causal variables and their variable interactions. There is uncertainty about causes, effects, and data. Using evidence-based (scientific) forecasting principles, we determined that a naïve no change extrapolation method was the appropriate benchmark. To be useful to policy makers, a proposed forecasting method would have to provide forecasts that were substantially more accurate than the benchmark. We calculated benchmark forecasts against the UK Met Office Hadley Centre\u27s annual average thermometer data from 1850 through 2007. For 20- and 50-year horizons the mean absolute errors were 0.18°C and 0.24°C. The accuracy of forecasts from our naïve model is such that even perfect forecasts would be unlikely to help policy makers. We nevertheless evaluated the Intergovernmental Panel on Climate Change\u27s 1992 forecast of 0.03°C-per-year temperature increases. The small sample of errors from ex ante forecasts for 1992 through 2008 was practically indistinguishable from the naïve benchmark errors. To get a larger sample and evidence on longer horizons we backcast successively from 1974 to 1850. Averaged over all horizons, IPCC errors were more than seventimes greater than errors from the benchmark. Relative errors were larger for longer backcast horizons