Significant effects of Pgi genotype and body reserves on lifespan in the Glanville fritillary butterfly

Individuals with a particular variant of the gene phosphoglucose isomerase (Pgi ) have been shown to have superior dispersal capacity and fecundity in the Glanville fritillary butterfly (Melitaea cinxia), raising questions about the mechanisms that maintain polymorphism in this gene in the field. Here, we investigate how variation in the Pgi genotype affects female and male life history under controlled conditions. The most striking effect is the longer lifespan of genotypes with high dispersal capacity, especially in nonreproducing females. Butterflies use body reserves for somatic maintenance and reproduction, but
different resources (in thorax versus abdomen) are used under dissimilar conditions, with some interactions with the Pgi genotype. These results indicate life-history trade-offs that involve resource allocation and genotype!environment interactions, and these trade-offs are likely to contribute to the maintenance of Pgi polymorphism in the natural populations.

Studies in the Sandalwood Oil Series. III. Chain Effect on Terpene Transformations

The carboxyl chain of some molecules has been found to be responsible for causing rearrangements and controlling their course. This chain effect, which operates during reactions involving carbonium ions, is illustrated with examples from Sandalwood oil chemistry.

Studies in the sandalwood-oil series. I. The structure, synthesis, and configuration of the lactone of tricycloekasantalic acid

The structure, synthesis, and configuration of the lactone of tricycloekasantalic acid have been described. It has been shown that in the formation of this lactone (XII) from the acids (I) or (II) a rearrangement is involved.

Compressible axially symmetric laminar boundary layer flow in the stagnation region of a blunt body in the presence of magnetic field

In this paper, the steady laminar viscous hypersonic flow of an electrically conducting fluid in the region of the stagnation point of an insulating blunt body in the presence of a radial magnetic field is studied by similarity solution approach, taking into account the variation of the product of density and viscosity across the boundary layer. The two coupled non-linear ordinary differential equations are solved simultaneously using Runge-Kutta-Gill method. It has been found that the effect of the variation of the product of density and viscosity on skin friction coefficient and Nusselt number is appreciable. The skin friction coefficient increases but Nusselt number decreases as the magnetic field or the total enthalpy at the wall increases

Contribution of different physical forces to the disjoining pressure of a thin water film being pressed by an oil droplet

With an objective to understand the nature of forces which contribute to the disjoining pressure of a thin water film on a steel substrate being pressed by an oil droplet, two independent sets of experiments were done. (i) A spherical silica probe approaches the three substrates; mica, PTFE and steel, in a 10 mM electrolyte solution at two different pHs (3 and 10). (ii) The silica probe with and without a smeared oil film approaches the same three substrates in water (pH = 6). The surface potential of the oil film/water was measured using a dynamic light scattering experiment. Assuming the capacity of a substrate for ion exchange the total interaction force for each experiment was estimated to include the Derjaguin-Landau-Verwey-Overbeek (DLVO) force, hydration repulsion, hydrophobic attraction and oil-capillary attraction. The best fit of these estimates to the force-displacement characteristics obtained from the two sets of experiment gives the appropriate surface potentials of the substrates. The procedure allows an assessment of the relevance of a specific physical interaction to an experimental configuration. Two of the principal observations of this work are: (i) The presence of a surface at constant charge, as in the presence of an oil film on the probe, significantly enhances the counterion density over what is achieved when both the surfaces allow ion exchange. This raises the corresponding repulsion barrier greatly. (ii) When the substrate surface is wettable by oil, oil-capillary attraction contributes substantially to the total interaction. If it is not wettable the oil film is deformed and squeezed out. (C) 2010 Elsevier Inc. All rights reserved.

The Physical Strenuousness of Work is Slightly Associated with an Upward Trend in the Body Mass Index

This paper explores the relationship between the physical strenuousness of work and the body mass index in Finland, using individual microdata over the period 1972-2002. The data contain self-reported information about the physical strenuousness of a respondent’s current occupation. Our estimates show that the changes in the physical strenuousness of work can explain around 8% at most of the definite increase in BMI observed over the period. The main reason for this appears to be that the quantitative magnitude of the effect of the physical strenuousness of work on BMI is rather moderate. Hence, according to the point estimates, BMI is only around 1.5% lower when one’s current occupation is physically very demanding and involves lifting and carrying heavy objects compared with sedentary job (reference group of the estimations), other things being equal. Accordingly, the changes in eating habits and the amount of physical activity during leisure time must be the most important contributors to the upward trend in BMI in industrialised countries, but not the changes in the labour market structure.

Temperature Distribution in Resin Impregnated Paper Insulation for Transformer Bushings

The overall reliability of a power transformer depends to a great extent on the sound operation of the bushings thereof. Oil impregnated paper (OIP) insulated bushings have been in use for a long time now. In many situations, it becomes necessary to avoid OIP insulation in bushings. In the recent past, a new technological breakthrough has been achieved whereby the OIP is replaced by epoxy resin impregnated crepe paper (RIP) insulation. This new system has several advantages over OIP and has now become the insulation of choice. However, its long time thermal and electrical performance need to be carefully assessed. This paper reports the results of a study of temperature distribution in the body of insulation, based on the ac conductivity of RIP insulation. A method of computing the maximum thermal voltage of this system is also given.

A Compact Model incorporating Quantum Effects for Ultra-Thin-Body Double-Gate MOSFETs

We propose a compact model which predicts the channel charge density and the drain current which match quite closely with the numerical solution obtained from the Full-Band structure approach. We show that, with this compact model, the channel charge density can be predicted by taking the capacitance based on the physical oxide thickness, as opposed to C-eff, which needs to be taken when using the classical solution.