Recent meta-analyses suggest that certain drugs act as cognitive enhancers and can increase attentional investment and performance even for healthy adults. The current review examines the potential of behavioral economics enhancers (BEEs) for similarly improving cognitive performance and judgments. Traditionally, behavioral economics theory has adopted a skeptical approach regarding the notion of whether individuals can overcome judgment biases through variables that increase cognitive effort. We focus mostly on the effects of two BEEs: incentivization and losses. Summarizing results from different meta-analyses, we find a small but robust positive effect size for BEEs, with comparable effect sizes to those found in studies of pharmacological cognitive enhancers.

Prospect Theory proposed that the (dis)utility of losses is always more than gains due to a phenomena called ‘loss-aversion’, a result obtained in multiple later studies over the years. However, some researchers found reversed or no loss-aversion for affective judgments of small monetary amounts but, those findings have been argued to stem from the way gains versus losses were measured. Thus, it was not clear whether loss-aversion does not show with affective judgments for smaller magnitudes, or it is a measurement error. This paper addresses the debate concerning loss-aversion (in the prospect theoretic sense) and judgments about the intensity of gains and losses. We measured affective prospective judgments for monetary amounts using measurement scales that have been argued to be suitable for measuring loss-aversion and hence rule out any explanations regarding measurement. Both in a gambling scenario (Experiments 1 and 2) and in the context of fluctuating prices (Experiments 3a and 3b), potential losses never loomed larger than gains for low magnitudes, indicating that it is not simply a measurement error. Moreover, for the same participant, loss aversion was observable at high magnitudes. Further, we show that loss-aversion disappears even for higher monetary values, if contextually an even larger anchor is provided. The results imply that Prospect Theory’s value function is contextually dependent on magnitudes.

This study aimed to examine the effects of re-ensiling time and Lactobacillus buchneri on the fermentation profile, chemical composition and aerobic stability of sugarcane silages. The experiment was set up as a repeated measure design consisting of four air-exposure periods (EP)(0, 6, 12, and 24 h) microbial additive (A) (L. buchneri; or lack of there), with five replicates. Sugarcane was ground through a stationary forage chopper and ensiled in four plastic drums of 200-L capacity. After 210 days of storage, the drums were opened and half of the silage mass was treated with L. buchneri at the concentration of 105 cfu/g of forage. Subsequently, the silages were divided into stacks. The re-ensiling process was started immediately, at 0, 6, 12 and 24-hour intervals, by transferring the material to PVC mini-silos. Silos were opened after 120 days of re-ensiling. The use of L. buchneri reduced butyrate concentration but did not change ethanol or acetic acid concentrations and aerobic stability. An interaction effect between L. buchneri and re-ensiling time was observed for dry matter (DM) losses and composition. Lactobacillus buchneri is not effective in improving aerobic stability in re-ensiled sugarcane silages. However, less DM is lost in silages treated with L. buchneri and exposed to air for 24 h. Re-ensiling sugar cane in up to 24 h of exposure to air does not change final product quality.

Water use by weeds is one type of loss that contributes to the cost of weeds to agriculture. Water use efficiency provides a mechanism by which water use by weeds can be estimated. Uncontrolled weed growth could result in estimated irrigation costs exceeding $50.00/ha. Weeds like barnyardgrass at threshold densities in irrigated crops like sugarbeet or tomato are estimated to increase production costs by about $20.00/ha depending on water cost.

Powdered maize cobs were tested as an alternative for pesticide use in stored maize. Five doses (2, 4, 6, 8 and 10 g/250 g seed) of powdered maize cobs applied at particle sizes of 1.4 and 0.4 mm diameter were compared with actellic powder against Sitophilus zeamais Motschulsky for 120 days. Mortality and survival data showed that cob powders did not act as fumigant but exerted a potent inhibition of progeny on direct contact with S. zeamais adults. The particle size of powdered cobs had no effect on maize damage and losses. At doses equal to or higher than 6 g powdered maize cobs/250 g grain maize, i.e. 2.4% (w/w), damage to grain was < 5% and weight losses < 1%. The protection offered at the highest dose was comparable to the pesticide control. The use of powdered maize cobs is discussed as a natural alternative to synthetic pesticides for protection of maize against S. zeamais.

A recent survey of actuarial practitioners in North America shows that smoothed-market actuarial asset values are commonly used in funding valuations of defined benefit pension plans. Four methods of calculating such values are reported in the actuarial literature but only qualitative descriptions of the methods are given. This paper provides mathematical descriptions of the “average of market”, “weighted average”, “deferred recognition” and “write-up” actuarial values. They are shown to be based on either arithmetic or exponential smoothing. Provided the same form of smoothing is used, the four methods are equivalent.

A detailed threshold analysis of room-temperature pulsed operation of GaN/AlGaN/AlN vertical-cavity surface-emitting lasers (VCSELs) is carried out. The model takes advantage of the latest results concerning gain in active regions, material absorption in the cladding layers, as well as cavity diffraction and scattering losses. The simulation showed that although VCSELs with single (S) or multiple (M) quantum-well (QW) active regions exhibit lower threshold currents, they are much more sensitive to any increase in optical losses than their bulk counterparts. In particular, decreasing the active region radius of gain-guided QW VCSELs below 5 μm (which increases diffraction losses) or increasing dislocation densities (which, in turn, raises scattering losses) gives an enormous rise to their threshold currents. Therefore small-size GaN VCSELs should have an index-guided structure. In the case of MQW VCSELs, the optimal number of quantum wells strongly depends on the reflectivities of resonator mirrors. According to our study, MQW GaN lasers usually require noticeably lower threshold currents compared to SQW lasers. The optimal number of QW active layers is lower in laser structures exhibiting lower optical losses. Although the best result occurred for an active region thickness of 4 nm, threshold currents for the various sizes differ insignificantly.

Since it was first reported in Tanzania in 1981 the Larger Grain Borer (LGB) has spread from a small area in the northwest of the country to 17 of the 20 regions. Only in the extreme south, along the Mozambique border, has the pest not been found. It has also become established in Kenya, Burundi, Togo and Benin.

LGB can cause very high weight loss in farm stored maize and dried cassava, commodities on which it is able to breed. After 5 months storage during the dry season in western Tanzania, mean losses of 9% were found, a much higher level than losses of less than 1% which would be expected in LGB-free areas in East/Central Africa.

Application of 0.5% permethrin dust at 2.8 ppm provides excellent protection against LGB when applied to loose maize grain for 1 year. However, the storage of shelled maize predisposes towards the development of Sitophilus species which can result in high losses being sustained. A “cocktail” of permethrin and pirimiphos-methyl, applied at 3.3 and 17.7 ppm respectively, successfully controls all storage pests and is currently being used in an extensive control campaign in Tanzania.

A multi-donor funded control and containment campaign, co-ordinated by FAO, has been in operation in Tanzania since 1984. The programme is comprised of a training element for agricultural staff and several field extension campaigns which assist with insecticide distribution and with dissemination of information to farmers. The primary objectives of the programme are to reduce farm storage losses and to contain LGB within the areas it is now found. In some regions, where LGB is relatively isolated, attempts are being made to eradicate it.

The methods for and the problems of recognizing bird and rodent damage are described. For birds the methodology for assessing the damage, and the necessary statistics for determining sample design and sample size exist. Damage is measured either by visual estimation of the percentage loss (sorghum, maize, millet) or by weighing/comparing of damaged/undamaged spikes/panicles (wheat/rice). Sampling usually involves randomly selected transects. A system is also available for assessing bird damage over large areas of District, Regional or even countrywide levels involving aerial surveys of crop hectarage and ground teams sampling damage levels at randomly selected points.

For rodents, the methodology is less well established but damage in the field is usually quantified in terms of the percentage of rows of cereals destroyed at germination (maize) or by the number of cut stems compared to uncut stems in sample quadrats (wheat, barley).

Manpower and resources for bird control do not often extend beyond control operation to damage assessments. As a result the necessity for and success of bird control has to be evaluated in terms of diminishing farmer complaints or expressions of farmer gratitude rather than objectively in terms of crop saved or cost-effectiveness. It is suggested that in the long run, emphasis must inevitably switch to damage assessments as the economic pressures on Africa continue to increase.

During the two years research 1983–1985 on traditional maize granaries in Togo, we studied three methods for loss assessment which are discussed by the FAO: the count and weigh method, the standard volume/weight method and the thousand-grain mass method.

In general, between 80 and 90% of the overall losses were caused by insect feedings. Besides Prostephanus truncatus (Horn), the most important storage pests were Sitophilus zeamais (Motsch.), Tribolium spp. and Cathartus quadricollis (Guèr.). Best results were given by the count and weigh method. The significantly highest losses of dry weight (12–13%) were found after 6 months in stored hybrids. At the same time, local varieties appeared much more adapted to traditional storage methods, exhibiting losses of only 3% under the same conditions. Lowest level of losses (<1%) were observed in regularly smoked granaries in the mountain regions. The mean losses of dry weight during primary season were found to be 6.4% after 6 months, while after a storage period of 4 months during the secondary season, losses were as high as 8%. In Togo, P. truncatus was observed for the first time in spring 1984. Because of the different damage P. truncatus causes on corn, a newly developed sample weight method was examined in an additional test. After 6 months of observation, this dangerous pest caused serious losses up to 30.2%.

Research on stem borer pests of sugarcane, maize and rice in Ghana is briefly reviewed. The work on the biology of the borers carried out at Asutsuare between October 1977 and January 1980 has pinpointed the fact that the practice of ratooning is the principal cause of a devastating build up of stem borers in the sugarcane fields. Cost/benefit analysis has revealed that as a result of discontinuation of this practice, there would be an initial gain of $13.4/ha. The profit should increase in subsequent years when the foci of borer infestations are removed as a result of the discontinuation of ratooning. The use of imported parasites as well as insecticide treatment in controlling the borer populations has been ineffective. Further work in developing novel control measures against sugarcane borers is still in progress. Only cultural methods have been found useful in limiting the damage caused by stem borers to maize. Losses caused by stem borers to the rice crop in Ghana are still not well established.