MUTANT STRAINS OF SACCHAROMYCES YEDO PRODUCING EXCESSES OF FUSEL ALCOHOLS

The possibility of increasing the production of fusel alcohols in fermentation with Saccharomyces yedo by means of induced mutations has been investigated. Mutations were induced by UV-irradiation and mutants that could be expected to produce excesses of isobutyl alcohol, isoamyl alcohol and optically active amyl alcohol were selected in a medium containing norvaline—a partial leucine antagonist. Thus, in the selection of mutants, the relationship between the biosynthesis of amino acids and the formation of higher alcohols was exploited. Using this technique, two different mutants were isolated. In the fermentation of a synthetic medium which was initially lacking in amino acids, one of the mutants produced excess of isoamyl alcohol while the other mutant produced excesses of both isobutyl and isoamyl alcohol.     

Dominance, prosocial orientation, and female preferences: Do nice guys really finish last?

Three multimethod studies (total N?=?348) probed the hypothesis that women's attraction to men would be influenced by male prosocial orientation. In Study 1, prosocial men were rated as more physically and sexually attractive, socially desirable, and desirable as dates than were nonprosocial men. Dominant men were no more attractive than low-dominance men, and male dominance did not interact with male prosocial orientation in eliciting attraction from women. In Study 2, prosocial orientation was manipulated to avoid "personalism," but still affected attraction. Across all measures attraction was an interactive function of dominance and prosocial tendencies. Dominance alone did not increase any form of attraction measured. In Study 3, male prosocial tendencies and dominance interacted to affect women's attraction to men. Results are discussed in terms of the place of altruism and dominance in evolutionary approaches to human interpersonal attraction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of temperature of thermal treatment on surface densification of spruce

Spruce (Picea abies L. Karst) wood lamellae, thermally treated at 170, 190, 210 and 230 °C were surface densified by compression at a temperature of 150 °C to three degrees of compression. Immediate springback, set recovery, mechanical properties in 3-point flexure, Brinell hardness and density profiles measurements were used to determine the effect of thermal treatment on the properties of surface densified wood. The highest immediate springback occurred in wood specimens thermally treated at the highest temperature (230 °C) and decreased with decreasing thermal treatment temperature. The untreated samples had the highest set recovery, which decreased with the temperature of thermal treatment. The surface densification increased hardness and bending strength. The highest increase was in the case of untreated wood and decreased with the temperature of thermal treatment. The modulus of elasticity (MOE) and modulus of rupture (MOR) of surface densified wood decreased with increasing thermal treatment temperature. The trend was similar for specimens which were thermally treated but not surface densified. Surface densification increased the density of the specimens in the first few millimetres below the surface. The highest density was achieved in untreated specimens and the lowest in specimens thermally treated at the highest temperature.     

Modeling stump biomass of stands using harvester measurements for adaptive energy wood procurement systems

The value and volumes of industrial stump fuel supply are increasing for energy production. Accurate estimates of aboveground and belowground biomass of trees are important when estimating the potential of stumps as a bioenergy source. In this study two stump biomass equations were adapted and tested using them as calibrated stump biomass models computed as the cumulative sum by a local stand. In addition, variables derived from stem measurements of the forest harvester data were examined to predict stump biomass of a stand by applying regression analysis. The true stump yield (dry weight) was used as the reference data in the study. Both biomass models performed well (adjusted R² ˜ 0.84) and no advance was found in using other stem dimensions as independent variables in the model. The stand-level model can be used in innovative stump biomass prediction tools for increasing efficiency of energy wood procurement planning to stands within a certain area. In practice, wood procurement managers would need to adapt developed system and decide whether the degree of accuracy/precision provided by the models is acceptable in their local stand harvesting conditions.     

Investments into forest biorefineries under different price and policy structures

Increasing scarcity of oil reserves and the high CO₂ emissions from using oil have contributed to the development of renewable biofuels. Pulp and paper mill integrated forest biorefineries offer one important means to increase biofuel production. This study analyzes the effects of policies to support biofuel production in the pulp and paper sector. We study the relative effectiveness of three biofuel supporting policy instruments, namely production subsidy, input subsidy and investment subsidy. We present a partial equilibrium pulp and paper market model with a biorefinery investment option. A numerical model is used to evaluate the impacts of policy instruments on wood prices, as well as input choices and investment strategies of pulp and paper industries. The data represent the Finnish pulp and paper sector. We evaluate the values and direct costs of the policy instruments in a situation of exogenous biofuel production targets. The direct costs of input and investment subsidies are higher than those of a production subsidy. With all the policy instruments, Finnish pulp and paper mills would invest in wood-gasifying technology, instead of black liquor based one. The number of biorefinery units is dependent on the subsidy type — investment and input subsidies are likely to result in more numerous but smaller biofuel production units than a production subsidy. With all the policy instruments the demand for wood increases in Finland leading to higher wood prices. This, in turn, could reflect negatively on the profitability of the pulp and paper industries. To a significant degree, the model and the results can be generalized to other countries and markets where integrated pulp and paper mills are operating.     

Refined genetic localization of the Best disease gene in 11q13 and physical mapping of linked markers on radiation hybrids

In the framework of the system of monitoring the environmental impact on population health, the concentration of lead, cadmium and selenium in blood and cadmium in urine was measured in adults (n = 670), children (n = 599) and umbilical blood (n = 549) using atomic absorption spectrophotometry. Furthermore, cytogenetic analysis of peripheral lymphocytes in all population groups under study was investigated. The median blood Pb level for the overall group of adults (47.8 micrograms/l, i.e. 0.23 mumol/1) was significantly higher in men (51.5 micrograms/l, i.e. 0.25 mumol/l). Smoking significantly influenced the blood Pb level in women. The 90th percentile in no group exceeded the value of 100 micrograms/l (0.48 mumol/l). The median blood Cd level in adults (0.9 microgram/l, i.e. 0.008 mumol/l) depends on smoking habit (1.25 micrograms/l, i.e. 0.01 mumol/l). The median urine Cd level was 0.585 microgram/g creatinine (0.59 mumol/mole creatinine) in adults and 0.37 microgram/g creatinine (0.37 mumol/mole creatinine) in children. The median blood Se level (53.5 micrograms/l, i.e. 0.68 mumol/l) was found to be higher in the group of non-smokers (57.5 micrograms/l, i.e 0.73 mumol/l). Lead and selenium level were significantly lower in the umbilical blood. Cytogenetic analysis results showed age-dependent average percentages of aberrant cells: 1.1% in umbilical blood, 1.27% in children and 1.71 in adults in line with the reference values for the Czech population.     

Tetrahedral mesh generation in convex primitives

This paper presents a method for generating tetrahedral meshes in three-dimensional primitives. Given a set of closed and convex polyhedra having non-zero volume and some mesh controlling parameters, the polyhedra are automatically split to tetrahedra satisfying the criteria of standard finite element meshes. The algorithm tries to generate elements close to regular tetrahedra by maximizing locally the minimum solid angles associated to a set of a few neighbouring tetrahedra. The input parameters define the size of the tetrahedra and they can be used to increase or decrease the discretization locally. All the new nodes, which are not needed to describe the geometry, are generated automatically.