Leakage of Anthocyanins from Skin of Thawed, Frozen Highbush Blueberries (Vaccinium corymbosum L.)

Factors affecting the tendency of thawed blueberries to leak pigmented exudate were investigated. Drip and anthocyanin leakage rates (ALR) were determined spectrophotometrically. Leakage vs time curves were linear or two-phase linear, ALR varying with cultivar, ripeness, and berry condition. Dewaxing increased ALR with most cultivars. ALR did not correlate with berry anthocyanin content, surface area, or cuticle thickness. ALR and amount of drip were poorly correlated. ALR varied from berry-to-berry within samples. Leakage was observed to be nonuniform on berry surfaces, appearing at skin cracks and ruptures, the calyx area, and other point sources. An hypothesis relating leakage to skin condition, fluid accumulation, and anthocyanin content is presented.     

Energy conservation in the industrial sector of developing countries

This paper begins by examining the most energy-intensive industries and methods by which fuel efficiency can be improved. Next the author analyses the economics of energy conservation using specific case studies drawn from India. It is shown that investing in energy efficiency is more economical Btu per Btu than investing in the enhancement of domestic energy resources. The author also assesses changes in the economics of conservation for private firms when there are government incentives. Finally government policies that can overcome economic and non-economic disincentives for investing in energy conservation are examined.     

Opening address: The world gas situation

Worldwide demand and supply of natural gas may rise substantially between the years 1982 and 2000, but the rate of increase will decelerate after 1990. The rapid growth of potential demand in the first decade is expected to take place in the developing countries in particular. During this period, gas production potential will rise most rapidly in Eastern Europe (including the U.S.S.R.) and in the Third World countries of Latin America, Africa, the Middle East, and Asia. In the year which has passed since the Venice Conference, forecasts of future natural gas demand in Western Europe have been reduced from 300–350 × 10⁹ m³ (in the year 2000) to 270 × 10⁹ m³. This change has greatly diminished the expected need for gas imports into Western Europe. It has also had a positive effect on the reserve position, relative to anticipated demand, of the Netherlands, which now will consider making more gas available for Western European markets.     

Worms and viruses and botnets, oh my! Rational responses to emerging Internet threats

No longer satisfied with compromising and controlling individual computers, a new breed of hackers have set their sights on virtual networks of zombie systems, which they use in concert to accomplish various nefarious deeds. Beware the botnet.     

Viscoplastic behaviour of stainless steels AISI 316L and 316H

Summary The theory of viscoplasticity based on total strain and overstress is used in order to simulate the sensitivity to the rate of loading of two commonly used stainless steels, namely AISI 316L and 316H. The consitutive model has been implemented within a transient finite element computer code using a stress update algorithm based on the elastic predictor-return mapping concept. Both monotonic and cyclic loading conditions are considered in one or more space dimensions. Experimental results showing strain-rate dependence at room temperature are reported for both types of steel and used for calibrating the viscoplastic numerical model. An explicit dependence of the nonlinear viscosity function on the strain rate has been obtained and the calibrated model is found to yield results which are in excellent agreement with the experimental data. Finally the calibrated viscoplastic model is applied to predict the response of two representative structures subjected to impulsive loading. The results indicate a significant effect of the rate of loading on the internal stress distribution. With 21 Figures