Bringing the target to the cursor: proxy targets for older adults

Studies in the literature have proposed techniques to facilitate pointing in graphical user interfaces through the use of proxy targets. Proxy targets effectively bring the target to the cursor, thereby reducing the distance that the cursor must travel. This paper describes a study which aims to provide an initial understanding of how older adults respond to proxy targets, and compares older with younger users. We found that users in both age groups adjusted to the proxy targets without difficulty, and there was no indication in the cursor trajectories that users were confused about which target, i.e. the original versus the proxy, was to be selected. In terms of times, preliminary results show that for younger users, proxies did not provide any benefits over direct selection, while for older users, times were increased with proxy targets. A full analysis of the movement times, error rates, throughput and subjective feedback is currently underway.

Twentieth century secular decrease in the atmospheric potential gradient

Current flowing in the global atmospheric electrical circuit (AEC) substantially decreased during the twentieth century. Fair-weather potential gradient (PG) observations in Scotland and Shetland show a previously unreported annual decline from 1920 to 1980, when the measurements ceased. A 25% reduction in PG occurred in Scotland 1920–50, with the maximum decline during the winter months. This is quantitatively explained by a decrease in cosmic rays (CR) increasing the thunderstorm-electrosphere coupling resistance, reducing the ionospheric potential VI. Independent measurements of VI also suggest a reduction of 27% from 1920–50. The secular decrease will influence fair weather atmospheric electrical parameters, including ion concentrations and aerosol electrification. Between 1920–50, the PG showed a negative correlation with global temperature, despite the positive correlation found recently between surface temperature and VI. The 1980s stabilisation in VI may arise from compensation of the continuing CR-induced decline by increases in global temperature and convective electrification.

The impact of traffic emissions on atmospheric ozone and OH: results from QUANTIFY

To estimate the impact of emissions by road, aircraft and ship traffic on ozone and OH in the present-day atmosphere six different atmospheric chemistry models have been used. Based on newly developed global emission inventories for road, ship and aircraft emission data sets each model performed sensitivity simulations reducing the emissions of each transport sector by 5%. The model results indicate that on global annual average lower tropospheric ozone responds most sensitive to ship emissions (50.6%±10.9% of the total traffic induced perturbation), followed by road (36.7%±9.3%) and aircraft exhausts (12.7%±2.9%), respectively. In the northern upper troposphere between 200–300 hPa at 30–60° N the maximum impact from road and ship are 93% and 73% of the maximum effect of aircraft, respectively. The latter is 0.185 ppbv for ozone (for the 5% case) or 3.69 ppbv when scaling to 100%. On the global average the impact of road even dominates in the UTLS-region. The sensitivity of ozone formation per NOx molecule emitted is highest for aircraft exhausts. The local maximum effect of the summed traffic emissions on the ozone column predicted by the models is 0.2 DU and occurs over the northern subtropical Atlantic extending to central Europe. Below 800 hPa both ozone and OH respond most sensitively to ship emissions in the marine lower troposphere over the Atlantic. Based on the 5% perturbation the effect on ozone can exceed 0.6% close to the marine surface (global zonal mean) which is 80% of the total traffic induced ozone perturbation. In the southern hemisphere ship emissions contribute relatively strongly to the total ozone perturbation by 60%–80% throughout the year. Methane lifetime changes against OH are affected strongest by ship emissions up to 0.21 (± 0.05)%, followed by road (0.08 (±0.01)%) and air traffic (0.05 (± 0.02)%). Based on the full scale ozone and methane perturbations positive radiative forcings were calculated for road emissions (7.3±6.2 mWm−2) and for aviation (2.9±2.3 mWm−2). Ship induced methane lifetime changes dominate over the ozone forcing and therefore lead to a net negative forcing (−25.5±13.2 mWm−2).

A vector approach to the assessment of undergraduate engineering courses

In any undergraduate engineering programme there is a need to assess the balance and flavour of the various educational strands. In order for a quality assurance of these programmes to be met there is a need to evaluate the course load, academic content and the assessment marks of each course in the undergraduate programme. The existing ranges of QA methods for these programmes are focused on one or two of these issues and do not provide a comprehensive assessment procedure. Following a review of the existing QA methods, this paper will define a three-dimensional approach to the assessment of the educational aspects of an undergraduate course. Various features of this method will be described and potential benefits explained.

Reactive Halogens in the Marine Boundary Layer (RHaMBLe): the tropical North Atlantic experiments

The NERC UK SOLAS-funded Reactive Halogens in the Marine Boundary Layer (RHaMBLe) programme comprised three field experiments. This manuscript presents an overview of the measurements made within the two simultaneous remote experiments conducted in the tropical North Atlantic in May and June 2007. Measurements were made from two mobile and one ground-based platforms. The heavily instrumented cruise D319 on the RRS Discovery from Lisbon, Portugal to São Vicente, Cape Verde and back to Falmouth, UK was used to characterise the spatial distribution of boundary layer components likely to play a role in reactive halogen chemistry. Measurements onboard the ARSF Dornier aircraft were used to allow the observations to be interpreted in the context of their vertical distribution and to confirm the interpretation of atmospheric structure in the vicinity of the Cape Verde islands. Long-term ground-based measurements at the Cape Verde Atmospheric Observatory (CVAO) on São Vicente were supplemented by long-term measurements of reactive halogen species and characterisation of additional trace gas and aerosol species during the intensive experimental period. This paper presents a summary of the measurements made within the RHaMBLe remote experiments and discusses them in their meteorological and chemical context as determined from these three platforms and from additional meteorological analyses. Air always arrived at the CVAO from the North East with a range of air mass origins (European, Atlantic and North American continental). Trace gases were present at stable and fairly low concentrations with the exception of a slight increase in some anthropogenic components in air of North American origin, though NOx mixing ratios during this period remained below 20 pptv (note the non-IUPAC adoption in this manuscript of pptv and ppbv, equivalent to pmol mol−1 and nmol mol−1 to reflect common practice). Consistency with these air mass classifications is observed in the time series of soluble gas and aerosol composition measurements, with additional identification of periods of slightly elevated dust concentrations consistent with the trajectories passing over the African continent. The CVAO is shown to be broadly representative of the wider North Atlantic marine boundary layer; measurements of NO, O3 and black carbon from the ship are consistent with a clean Northern Hemisphere marine background. Aerosol composition measurements do not indicate elevated organic material associated with clean marine air. Closer to the African coast, black carbon and NO levels start to increase, indicating greater anthropogenic influence. Lower ozone in this region is possibly associated with the increased levels of measured halocarbons, associated with the nutrient rich waters of the Mauritanian upwelling. Bromide and chloride deficits in coarse mode aerosol at both the CVAO and on D319 and the continuous abundance of inorganic gaseous halogen species at CVAO indicate significant reactive cycling of halogens. Aircraft measurements of O3 and CO show that surface measurements are representative of the entire boundary layer in the vicinity both in diurnal variability and absolute levels. Above the inversion layer similar diurnal behaviour in O3 and CO is observed at lower mixing ratios in the air that had originated from south of Cape Verde, possibly from within the ITCZ. ECMWF calculations on two days indicate very different boundary layer depths and aircraft flights over the ship replicate this, giving confidence in the calculated boundary layer depth.

Plastic films for polytunnels can prolong the effective residual life of cypermethrin to over 6 months

Synthetic pyrethroid insecticides are degraded almost entirely by ultraviolet (UV)-catalysed oxidation. A bioassay using the beetle Tribolium confusum duVal caged on bandages soaked in 0.04% a.i. cypermethrin showed large differences in residual insecticide-life under three plastic films available for cladding polytunnels. Cypermethrin exposed to a UV film that transmitted 70% of UVB and 80% of UVA killed all beetles for 8 weeks, compared to only 3 weeks for cypermethrin exposed in a clear plastic envelope. Cypermethrin under a UV-absorbing film that reduced the transmission of UVB and UVA to 14% and 50%, respectively, gave a complete kill for 17 weeks. Reducing the transmission of UVB to virtually zero, and that of UVA to only 3%, using a UV-opaque film prolonged the effective life of the cypermethrin residue to 26 weeks, and some beetles were still killed for a further 11 weeks. Even after this time, beetles exposed to cypermethrin from the UV-opaque treatment were still affected by the insecticide, and only showed near-normal mobility after 24 months of pesticide exposure to the UV-opaque film. These results have implications for the recommended intervals between cypermethrin treatment and crop harvest, and on the time of introduction of insect-based biological control agents, when UV-opaque films are used in commercial horticulture.

Non-normal real estate return distributions by property type in the UK

Investment risk models with infinite variance provide a better description of distributions of individual property returns in the IPD UK database over the period 1981 to 2003 than normally distributed risk models. This finding mirrors results in the US and Australia using identical methodology. Real estate investment risk is heteroskedastic, but the characteristic exponent of the investment risk function is constant across time – yet it may vary by property type. Asset diversification is far less effective at reducing the impact of non‐systematic investment risk on real estate portfolios than in the case of assets with normally distributed investment risk. The results, therefore, indicate that multi‐risk factor portfolio allocation models based on measures of investment codependence from finite‐variance statistics are ineffective in the real estate context

Investigation of the faecal microbiota of geriatric cats

Aims: To investigate the faecal microbiota of geriatric cats, as aging affects the nutrient digestibility and metabolic function of the feline intestine. Methods and results: 20 geriatric cats were randomly assigned to two groups that were fed different foods. Coriobacteriaceae, Clostridium cluster XIV, bifidobacteria, and lactic acid bacteria were the dominant faecal bacterial groups, accounting for ∼40% of total bacteria. Clostridium cluster IX was less predominant (0.5% of total bacteria), while the remaining bacterial populations enumerated only accounted for 0.2% of total bacteria. Highly diverse microbial profiles were demonstrated for geriatric cats with denaturing gradient gel electrophoresis, although a few common bands were evident. Some differences were seen in the feline faecal microbiota between animal groups at the same time or over time for individual animals. However, no obvious clustering based on animal group or sample time was indicated. Conclusions: geriatric cats harboured a complex faecal microbiota and ∼41% of total bacteria have been detected with the probes employed. Significance and impact of study: First molecular-based study examining faecal microbiota of geriatric felines. Knowledge of the microbiota associated with ageing in cats may allow improved development of foods specific for the needs of senior cats.

Non-normal real estate return distributions by property type in the U.K.

Investment risk models with infinite variance provide a better description of distributions of individual property returns in the IPD database over the period 1981 to 2003 than Normally distributed risk models, which mirrors results in the U.S. and Australia using identical methodology. Real estate investment risk is heteroscedastic, but the Characteristic Exponent of the investment risk function is constant across time yet may vary by property type. Asset diversification is far less effective at reducing the impact of non-systematic investment risk on real estate portfolios than in the case of assets with Normally distributed investment risk. Multi-risk factor portfolio allocation models based on measures of investment codependence from finite-variance statistics are ineffectual in the real estate context.

The impact of real estate on the terminal wealth of the UK mixed-asset portfolio

The argument for the inclusion of real estate in the mixed-asset portfolio has concentrated on examining its effect in reducing the portfolio risk - the time series standard deviation (TSSD), mainly using ex-post time series data. However, the past as such is not really relevant to the long-term institutional investors, such as the insurance companies and pension funds, who are more concerned the terminal wealth (TW) of their investments and the variability of this wealth, the terminal wealth standard deviation (TWSD), since it is from the TW of their investment portfolio that policyholders and pensioners will derive their benefits. These kinds of investors with particular holding period requirements will be less concerned about the within period volatility of their portfolios and more by the possibility that their portfolio returns will fail to finance their liabilities. This variability in TW will be closely linked to the risk of shortfall in the quantity of assets needed to match the institution’s liabilities. The question remains therefore can real estate enhance the TW of the mixed-asset portfolio and/or reduce the variability of the TW. This paper uses annual data from the United Kingdom (UK) for the period 1972-2001 to test whether real estate is an asset class that not only reduces ex-post portfolio risk but also enhances portfolio TW and/or reduces the variability of TW.

The impact of real estate on the mixed-asset portfolio in periods of financial stress

The case for holding real estate in the mixed-asset portfolio is typically made on its stabilising effect as a result of its diversification benefits. However, portfolio diversification often fails when it is most needed, i.e. during periods of financial stress. In these periods, the variability of returns for most asset classes increases thus reducing the stabilising effect of a diversified portfolio. This paper applies the approach of Chow et al (1999) to the US domestic mixed-asset portfolio to establish whether real estate, represented by REITs, is especially useful in times of financial stress. To this end monthly returns data on five assets classes: large cap stocks, small cap stocks, long dated government bonds, cash (T-Bills) and real estate (REITs) are evaluated over the period January 1972 to December 2001. The results indicate that the inclusion of REITs in the mixed-asset portfolio can lead to increases or decreases in returns depending on the asset class replaced and whether the period is one of calm or stress. However, the inclusion of REITs invariably leads to reductions in portfolio risk that are greater than any loss in return, especially in periods of financial stress. In other words, REITs acts as a stabilising force on the mixed-asset portfolio when it is most needed, i.e. in periods of financial stress.

Lumbricus terrestris L. does not impact on the remediation efficiency of compost and biochar amendments

The aim of this study was to test the impact of compost and Biochar, with or without earthworms, on the mobility and availability of metals, and on the growth of grass to re-vegetate contaminated soil from the Parys Mountain mining site, Anglesey. We also determined if the addition of earthworms compromises remediation efforts. In a laboratory experiment, contaminated soil (1343 mg Cu kg−1, 2511 mg Pb kg−1 and 262 mg Zn kg−1) was remediated with compost and/or Biochar. After 77 days Lumbricus terrestris L. earthworms were added to the treatment remediated with both compost and Biochar, and left for 28 days. L. terrestris was not able to survive in the Biochar, compost or unamended treatments. A germination and growth bioassay, using Agrostis capillaris (Common Bent) was then run on all treatments for 28 days. The combination of Biochar and compost decreased water soluble Cu (from 5.6 to 0.2 mg kg−1), Pb (0.17 to less than 0.007 mg kg−1) and Zn (3.3 to 0.05 mg kg−1) in the contaminated soil and increased the pH from 2.7 to 6.6. The addition of L. terrestris to this treatment had no effect on the concentration of the water soluble metals in the remediated soil. The compost was the only treatment that resulted in germination and growth of A. capillaris suitable for re-vegetation purposes. However, the combination of compost, Biochar (with or without L. terrestris) produced the lowest concentrations of Cu (8 mg kg−1) and Zn (36 mg kg−1) in the aboveground biomass, lower than the compost treatment (15 mgCu kg−1 and 126 mgZn kg−1). The addition of Biochar and compost both separately and as co-amendments was effective in reducing the mobility and availability of metals. The addition of L. terrestris did not re-mobilise previously sequestered metals.

The impact of catechol-O-methyltransferase genotype on the acute responsiveness of vascular reactivity to a green tea extract

The beneficial effects of green tea catechins, such as the proposed improvement in endothelial function, may be influenced by phase II metabolism during and after absorption. The methylation enzyme, catechol-O-methyltransferase (COMT), has a missense mutation rs4680 (G to A), proposed to result in a 40 % reduction in enzyme activity. In the present pilot study, twenty subjects (ten of each homozygous COMT genotype) were recruited. Green tea extract capsules (836 mg green tea catechins) were given in a fasted state, and a high-carbohydrate breakfast was given after 60 min. Blood samples and vascular function measurements were taken at regular intervals. The change in digital volume pulse stiffness index (SI) from baseline was shown to be different between genotype groups at 120 and 240 min, with a lower SI in the GG individuals (P ≤ 0·044). The change in blood pressure from baseline also differed between genotype groups, with a greater increase in systolic (P = 0·023) and diastolic (P = 0·034) blood pressure at 120 min in the GG group. The AA group was shown to have a greater increase in insulin concentrations at 120 min (P = 0·019) and 180 min (P = 0·008) compared with baseline, despite similar glucose profiles. No genotypic differences were found in vascular reactivity measured using laser Doppler iontophoresis, total nitrite, lipids, plasma total antioxidant capacity or inflammatory markers after ingestion of the green tea extract. In conclusion, SI and insulin response to the glucose load differed between the COMT genotype groups, and this may be suggestive of a green tea extract and genotype interaction.

Case study on the whole life carbon cycle in buildings

Global temperatures are expected to rise by between 1.1 and 6.4oC this century, depending, to a large extent, on the amount of carbon we emit to the atmosphere from now onwards. This warming is expected to have very negative effects on many peoples and ecosystems and, therefore, minimising our carbon emissions is a priority. Buildings are estimated to be responsible for around 50% of carbon emissions in the UK. Potential reductions involve both operational emissions, produced during use, and embodied emissions, produced during manufacture of materials and components, and during construction, refurbishments and demolition. To date the major effort has focused on reducing the, apparently, larger operational element, which is more readily quantifiable and reduction measures are relatively straightforward to identify and implement. Various studies have compared the magnitude of embodied and operational emissions, but have shown considerable variation in the relative values. This illustrates the difficulties in quantifying embodied, as it requires a detailed knowledge of the processes involved in the different life cycle phases, and requires the use of consistent system boundaries. However, other studies have established the interaction between operational and embodied, which demonstrates the importance of considering both elements together in order to maximise potential reductions. This is borne out in statements from both the Intergovernmental Panel on Climate Change and The Low Carbon Construction Innovation and Growth Team of the UK Government. In terms of meeting the 2020 and 2050 timeframes for carbon reductions it appears to be equally, if not more, important to consider early embodied carbon reductions, rather than just future operational reductions. Future decarbonisation of energy supply and more efficient lighting and M&E equipment installed in future refits is likely to significantly reduce operational emissions, lending further weight to this argument. A method of discounting to evaluate the present value of future carbon emissions would allow more realistic comparisons to be made on the relative importance of the embodied and operational elements. This paper describes the results of case studies on carbon emissions over the whole lifecycle of three buildings in the UK, compares four available software packages for determining embodied carbon and suggests a method of carbon discounting to obtain present values for future emissions. These form the initial stages of a research project aimed at producing information on embodied carbon for different types of building, components and forms of construction, in a simplified form, which can be readily used by building designers in optimising building design in terms of minimising overall carbon emissions. Keywords: Embodied carbon; carbon emission; building; operational carbon.

The effect of exogenous gonadotropins on ovarian function in goats actively immunized against inhibin

The aim of this investigation was to compare the ovarian response to superovulatory treatments in does before and after inhibin immunization, with a view to optimizing the superovulatory potential of the caprine ovary. To avoid interference by the ovarian cycle, the experiment was conducted out-of-season. At the onset of the experiment 48 does were subjected to treatment with an sc implant of the progestogen norgestomet, combined with a gonadotropin; eight does each received a single injection of 1200 IU eCG, 400 IU eCG or 2 mL physiological saline (control) or six injections (at 12 h intervals) constituting 16 or 5.4 AU pFSH. The does were mated and subjected to embryo collection 6 to 7 d later. Throughout the experiment ovarian function (by ultrasonography) and plasma levels of inhibin antibodies and progesterone were monitored. Of 40 does treated during the first part of the experiment, 48% showed estrus. The ovarian response in does treated with a high or low dose of eCG or a low dose of pFSH was barely in excess of the ovarian response in the saline-treated controls, whereas a superovulatory dose of pFSH (16 AU) gave a satisfactory response of, on average, 14.5 ovulations (yielding 8.8 flushed ova and embryos). Immediately after the does had been subjected to embryo collection they were actively immunized against inhibin by administering two injections of a recombinant α-subunit of ovine inhibin at four week intervals. All immunized does produced antibodies with the maximal titer reached two weeks after the second injection. Groups of immunized does were subjected to the same gonadotropin treatments as before (avoiding allocation of individuals to the same treatments). This time all does showed estrous symptoms. The ovulatory response to the various treatments, including the saline controls, was virtually identical, the overall average being 21.8 follicles and 9.1 ovulations. The average embryo yield per doe was 5.7. The results imply that inhibin acted as the key factor in determining the ovulatory response since no impact of any of the supplementary gonadotropins was noted in inhibin-immunized does. This finding gives rise to the notion that inhibin antibodies may act primarily by an intraovarian paracrine action rather than by reducing the suppressive action of inhibin on pituitary FSH release. Further, these findings confirm earlier reports that eCG is less suitable than FSH for inducing superovulation in goats, and indicate that active immunization against inhibin may be considered a viable alternative to using exogenous gonadotropin for inducing superovulation in goats.