Senioritis in repose

Media and other accounts of life after retirement suggest it to be “The Golden Years” of life, when the elderly have true leisure in the classic sense of freedom from responsibilities of work. However, like earlier time-diary studies, data from the 2003-07 Americans Time Use Project (ATUS) indicate that the great majority of seniors’ extra 20+ hours of free time is concentrated on three activities – TV, reading and rest. Only a few more hours are spent on sleep. Despite reports of increased work time among seniors, relatively few of those in Andy’s new age bracket remain in the labor force and they work fewer hours.Time use, elderly, retirement, free time, TV, aging

Sleep as a victim of the “time crunch” – A multinational analysis

As reflected in many popular and academic writings, there is general concern that contemporary life is becoming ruled by a societal “time crunch”, in which work and family pressures make daily life more hectic. One implica-tion of this condition is that sleep time has been reduced in order to accommodate these pressures. While this view seems supported by recent national surveys in which Americans now claim to get less than 7 hours of sleep a night, it is not supported by sleep times reported in 2003-07 ATUS time diaries. If anything, time-diary sleep hours are higher than in previous decades, approaching 60 hours a week in both the US and Canada. Similar levels of sleep hours are found in 18 European counties, with most of those having trend data also showing no decrease in sleep over recent decades, with the exceptions of Germany and Japan. The major predictors of sleep time in US and Canada are work hours and, increasingly, education. The US-Canada finding that women sleep slightly more than men is mainly a reflection of these two predictors. Higher sleep for women is also found in more Northern and Western European countries, but not in more Eastern and Southern Europe; moreover, men in Japan, the country with by far the least sleep report more diary hours of sleep than women.Sleep time, time-diary sleep hours, men, women

Simulation of Alternative Marketing Strategies for U.S. Cotton

Three marketing strategies (selling a put option, cash sale at harvest, and cash sale in June) are simulated based on historical values and ranked based on certainty equivalents for a representative irrigated and dryland cotton farm Scenario analysis is also used to compare varying yield values.Simulation, Marketing, Cotton, Risk, Marketing, Research Methods/ Statistical Methods,

SOCIAL IMPLICATIONS OF THE INTERNET

The Internet is a critically important research site for sociologists testing theories of technology diffusion and media effects, particularly because it is a medium uniquely capable of integrating modes of communication and forms of content. Current research tends to focus on the Internet’s implications in five domains: 1) inequality (the “digital divide”); 2) community and social capital; 3) political participation; 4) organizations and other economic institutions; and 5) cultural participation and cultural diversity. A recurrent theme across domains is that the Internet tends to complement rather than displace existing media and patterns of behavior. Thus in each domain, utopian claims and dystopic warnings based on extrapolations from technical possibilities have given way to more nuanced and circumscribed understandings of how Internet use adapts to existing patterns, permits certain innovations, and reinforces particular kinds of change. Moreover, in each domain the ultimate social implications of this new technology depend on economic, legal, and policy decisions that are shaping the Internet as it becomes institutionalized. Sociologists need to study the Internet more actively and, particularly, to synthesize research findings on individual user behavior with macroscopic analyses of institutional and political-economic factors that constrain that behavior.World Wide Web, communications, media, technology

The application of microwave heating in bioenergy: A review on the microwave pre-treatment and upgrading technologies for biomass

Bioenergy, derived from biomass and/or biological (or biomass-derived) waste residues, has been acknowledged as a sustainable and clean burning source of renewable energy with the potential to reduce our reliance on fossil fuels (such as oil and natural gas). However, many bioenergy processes require some form of pre-treatment and/or upgrading procedure for biomass to generate a modified residue with more suitable properties and render it more compatible with the specific energy conversion route chosen. Many of these pre-treatments (or upgrading procedures) involve some form of substantive heating of the biomass to achieve this modification. Microwave (MW) heating has attracted much attention in recent years due to the advantages associated with dielectric heating effects. These advantages include rapid and efficient heating in a controlled environment, increasing processing rates and substantially shortening reaction times by up to 80%. However, despite this interest, the growth of industrial MW heating applications for bioenergy production has been hindered by a lack of understanding of the fundamentals of the MW heating mechanism when applied to biomass and waste residues. This article presents a review of the current scientific literature associated with the application of microwave heating for both the pre-treatment and upgrading of various biomass feedstocks across different bioenergy conversion pathways including thermal and biochemical processes. The fundamentals behind microwave heating will be explained, as well as discussion of the imperative areas which require further research and development to bridge the gap between fundamental science in the laboratory and the successful application of this technology at a commercial scale

Characterisation of potato crisp effective porosity using micro-CT

Background The effective porosity is an important quantitative parameter for food products that has a significant effect on taste and quality. It is challenging to quantify the apparent porosity of fried potato crisps as they have a thin irregularly shaped cross section containing oil and water. This study uses a novel micro-CT technique to determine the solid volume fraction and hence the effective porosity of three types of potato crisps: standard continuously fried crisps, microwaved crisps, and continuously fried ‘kettle’ crisps. Results It was found that continuously fried kettle crisps had the lowest effective porosity at 0.54, providing the desired crunchy taste and lower oil contents. Crisps produced using a microwave process designed to mimic the dehydration process of standard continuous fried crisps had an effective porosity of 0.65, which was very similar to the effective porosity of 0.63 for standard continuously fried crisps. The results were supported by the findings of a forced preference consumer test. Conclusion The effective porosity affects the product taste and is therefore a critical parameter. This study shows that micro-CT analysis can be used to characterise the change in effective porosity of a thin irregularly shaped food product, caused by a change of cooking procedure

Inverse Fourier transform technique of measuring averaged absorption cross section in the reverberation chamber and Monte Carlo study of its uncertainty

The averaged absorption cross section (ACS) of a lossy object characterises its ability to capture power from diffused electromagnetic waves. The averaged ACS is very important in many EMC research areas such as indoor wireless channel modelling and human safety exposure study. The measurement of averaged ACS in a reverberation chamber can be achieved by measuring the rate of power loss in the time domain, however this technique requires dense frequency sampling for taking the inverse Fourier transform, which is very time consuming. A new scenario which accelerates the measurement speed is presented in this paper. It combines the technique of non-linear curve fitting to the power delay profile, segmented frequency sweeping and continuous mode stirring. The scenario was validated by measuring the averaged ACS of a hollow plastic sphere filled with deionized water in an EMC reverberation chamber. Measurement results showed a good accordance with the simulations and the measurement uncertainty was studied numerically with the Monte Carlo method

Optimisation of extraction and sludge dewatering efficiencies of bio-flocculants extracted from Abelmoschus esculentus (okra)

The production of natural biopolymers as flocculants for water treatment is highly desirable due to their inherent low toxicity and low environmental footprint. In this study, bio-flocculants were extracted from Hibiscus/Abelmoschus esculentus (okra) by using a water extraction method, and the extract yield and its performance in sludge dewatering were evaluated. Single factor experimental design was employed to obtain the optimum conditions for extraction temperature (25–90 °C), time (0.25–5 h), solvent loading (0.5–5 w/w) and agitation speed (0–225 rpm). Results showed that extraction yield was affected non-linearly by all experimental variables, whilst the sludge dewatering ability was only influenced by the temperature of the extraction process. The optimum extraction conditions were obtained at 70 °C, 2 h, solvent loading of 2.5 w/w and agitation at 200 rpm. Under the optimal conditions, the extract yield was 2.38%, which is comparable to the extraction of other polysaccharides (0.69–3.66%). The bio-flocculants displayed >98% removal of suspended solids and 68% water recovery during sludge dewatering, and were shown to be comparable with commercial polyacrylamide flocculants. This work shows that bio-flocculants could offer a feasible alternative to synthetic flocculants for water treatment and sludge dewatering applications, and can be extracted using only water as a solvent, minimising the environmental footprint of the extraction process