Preexisting compensatory amino acids compromise fitness costs of a HIV-1 T cell escape mutation.

BACKGROUND: Fitness costs and slower disease progression are associated with a cytolytic T lymphocyte (CTL) escape mutation T242N in Gag in HIV-1-infected individuals carrying HLA-B*57/5801 alleles. However, the impact of different context in diverse HIV-1 strains on the fitness costs due to the T242N mutation has not been well characterized. To better understand the extent of fitness costs of the T242N mutation and the repair of fitness loss through compensatory amino acids, we investigated its fitness impact in different transmitted/founder (T/F) viruses. RESULTS: The T242N mutation resulted in various levels of fitness loss in four different T/F viruses. However, the fitness costs were significantly compromised by preexisting compensatory amino acids in (Isoleucine at position 247) or outside (glutamine at position 219) the CTL epitope. Moreover, the transmitted T242N escape mutant in subject CH131 was as fit as the revertant N242T mutant and the elimination of the compensatory amino acid I247 in the T/F viral genome resulted in significant fitness cost, suggesting the fitness loss caused by the T242N mutation had been fully repaired in the donor at transmission. Analysis of the global circulating HIV-1 sequences in the Los Alamos HIV Sequence Database showed a high prevalence of compensatory amino acids for the T242N mutation and other T cell escape mutations. CONCLUSIONS: Our results show that the preexisting compensatory amino acids in the majority of circulating HIV-1 strains could significantly compromise the fitness loss due to CTL escape mutations and thus increase challenges for T cell based vaccines.

Assessing the Transaction Costs of Firms in the EU ETS: Lessons form Ireland

Until now, there has been little empirical evidence that EU Emissions Trading Scheme (ETS) transaction costs are incurred at firm level. The transaction costs (internal costs, capital costs, consultancy and trading costs) incurred by Irish firms under the EU ETS during its pilot phase (2005-2007) were measured and analysed. Evidence for the sources of transaction costs, their magnitude and the distribution of costs shows that these were mainly administrative in nature. Considerable variation in costs was found due to economies of scale, as the costs per tonne of CO2 were lower for participants with larger allocations. For the largest firms - accounting for over half the emissions - average transaction costs were €0.05 per tonne. However, for small firms, average transaction costs were €2.02 - over 18% of the current allowance price. This supports the concerns that transaction costs are excessive for smaller participants. The immediate policy implication is that additional attention will be needed to address different sizes of firms, number of installations per firm, and the size of the initial allocations.

Hidden costs of control: four repetitions and an extension

We report four repetitions of Falk and Kosfeld's (Am. Econ. Rev. 96(5):1611-1630, 2006) low and medium control treatments with 476 subjects. Each repetition employs a sample drawn from a standard subject pool of students and demographics vary across samples. We largely confirm the existence of hidden costs of control but, contrary to the original study, hidden costs of control are usually not substantial enough to significantly undermine the effectiveness of economic incentives. Our subjects were asked, at the end of the experimental session, to complete a questionnaire in which they had to state their work motivation in hypothetical scenarios. Our questionnaires are identical to the ones administered in Falk and Kosfeld's (Am. Econ. Rev. 96(5):1611-1630, 2006) questionnaire study. In contrast to the game play data, our questionnaire data are similar to those of the original questionnaire study. In an attempt to solve this puzzle, we report an extension with 228 subjects where performance-contingent earnings are absent i.e. both principals and agents are paid according to a flat participation fee. We observe that hidden costs significantly outweigh benefits of control under hypothetical incentives.

Overweight and obesity on the island of Ireland: an estimation of costs

Objectives The increasing prevalence of overweight and obesity worldwide continues to compromise population health and creates a wider societal cost in terms of productivity loss and premature mortality. Despite extensive international literature on the cost of overweight and obesity, findings are inconsistent between Europe and the USA, and particularly within Europe. Studies vary on issues of focus, specific costs and methods. This study aims to estimate the healthcare and productivity costs of overweight and obesity for the island of Ireland in 2009, using both top-down and bottom-up approaches.

Methods Costs were estimated across four categories: healthcare utilisation, drug costs, work absenteeism and premature mortality. Healthcare costs were estimated using Population Attributable Fractions (PAFs). PAFs were applied to national cost data for hospital care and drug prescribing. PAFs were also applied to social welfare and national mortality data to estimate productivity costs due to absenteeism and premature mortality.

Results The healthcare costs of overweight and obesity in 2009 were estimated at €437 million for the Republic of Ireland (ROI) and €127.41 million for NI. Productivity loss due to overweight and obesity was up to €865 million for ROI and €362 million for NI. The main drivers of healthcare costs are cardiovascular disease, type II diabetes, colon cancer, stroke and gallbladder disease. In terms of absenteeism, low back pain is the main driver in both jurisdictions, and for productivity loss due to premature mortality the primary driver of cost is coronary heart disease.

Conclusions The costs are substantial, and urgent public health action is required in Ireland to address the problem of increasing prevalence of overweight and obesity, which if left unchecked will lead to unsustainable cost escalation within the health service and unacceptable societal costs.

Internalising the external costs of light and heavy goods vehicle transport in London

Report produced as part of the Green Logistics project (EPSRC and Department for Transport funded). This report provides estimates of the total external costs of LGV and HGV operations in London. In 2006, total LGV and HGV activity imposed external costs of approximately £1.75-£1.8 billion using low, medium and high emission cost values. About 27 per cent of these costs were internalised by duties and taxes paid by LGV operators, compared with 26% in the case of HGVs. If congestion costs are excluded, taxes and duties paid by LGV operators are estimated to be 155% of LGVs' allocated infrastructural and environmental costs, compared with 85% in the case of HGVs. When using the medium emission cost values, LGVs accounted for 56% of these external costs in London and HGVs for 44%.

Internalising the external costs of light and heavy goods vehicles in London

This report provides estimates of the total external costs of LGV and HGV operations in London. In 2006, total LGV and HGV activity imposed external costs of approximately £1.75-£1.8 billion using low, medium and high emission cost values. About 27 per cent of these costs were internalised by duties and taxes paid by LGV operators, compared with 26% in the case of HGVs. If congestion costs are excluded, taxes and duties paid by LGV operators are estimated to be 155% of LGVs' allocated infrastructural and environmental costs, compared with 85% in the case of HGVs. When using the medium emission cost values, LGVs accounted for 56% of these external costs in London and HGVs for 44%.

Product innovation and the costs of energy-using product policies

Energy-using Products (EuPs) contribute significantly to the United Kingdom’s CO2 emissions, both in the domestic and non-domestic sectors. Policies that encourage the use of more energy efficient products (such as minimum performance standards, energy labelling, enhanced capital allowances, etc.) can therefore generate significant reductions in overall energy consumption and hence, CO2 emissions. While these policies can impose costs on the producers and consumers of these products in the short run, the process of product innovation may reduce the magnitude of these costs over time. If this is the case, then it is important that the impacts of innovation are taken into account in policy impact assessments. Previous studies have found considerable evidence of experience curve effects for EuP categories (e.g. refrigerators, televisions, etc.), with learning rates of around 20% for both average unit costs and average prices; similar to those found for energy supply technologies. Moreover, the decline in production costs has been accompanied by a significant improvement in the energy efficiency of EuPs. Building on these findings and the results of an empirical analysis of UK sales data for a range of product categories, this paper sets out an analytic framework for assessing the impact of EuP policy interventions on consumers and producers which takes explicit account of the product innovation process. The impact of the product innovation process can be seen in the continuous evolution of the energy class profiles of EuP categories over time; with higher energy classes (e.g. A, A+, etc.) entering the market and increasing their market share, while lower classes (e.g. E, F, etc.) lose share and then leave the market. Furthermore, the average prices of individual energy classes have declined over their respective lives, while new classes have typically entered the market at successively lower “launch prices”. Based on two underlying assumptions regarding the shapes of the “lifecycle profiles” for the relative sales and the relative average mark-ups of individual energy classes, a simple simulation model is developed that can replicate the observed market dynamics in terms of the evolution of market shares and average prices. The model is used to assess the effect of two alternative EuP policy interventions – a minimum energy performance standard and an energy-labelling scheme – on the average unit cost trajectory and the average price trajectory of a typical EuP category, and hence the financial impacts on producers and consumers.

How to improve supply chain performance of a specialized retailer: Managing landed costs of Zippy’s global supply chain

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

The costs of alcohol, illegal drugs, and tobacco in Canada, 2002.

Objective: The aim of this study was to estimate costs attributable to substance use and misuse in Canada in 2002. Method: Based on information about prevalence of exposure and risk relations for more than 80 disease categories, deaths, years of life lost, and hospitalizations attributable to substance use and misuse were estimated. In addition, substance-attributable fractions for criminal justice expenditures were derived. Indirect costs were estimated using a modified human capital approach. Results: Costs of substance use and misuse totaled almost Can. $40 billion in 2002. The total cost per capita for substance use and misuse was about Can. $1,267: Can. $463 for alcohol, Can. $262 for illegal drugs, and Can. $541 for tobacco. Legal substances accounted for the vast majority of these costs (tobacco: almost 43% of total costs; alcohol: 37%). Indirect costs or productivity losses were the largest cost category (61%), followed by health care (22%) and law enforcement costs (14%). More than 40,000 people died in Canada in 2002 because of substance use and misuse: 37,209 deaths were attributable to tobacco, 4,258 were attributable to alcohol, and 1,695 were attributable to illegal drugs. A total of about 3.8 million hospital days were attributable to substance use and misuse, again mainly to tobacco. Conclusions: Substance use and misuse imposes a considerable economic toll on Canadian society and requires more preventive efforts.

Costs to farmers of a tuberculosis breakdown

An on-farm survey of 151 cattle farmers who had experienced a bovine tuberculosis (Mycobacterium bovis) breakdown on their farms was undertaken in 2003 to assess the costs associated with the breakdown. In 90 per cent of cases the cost was estimated to be less than 18,513 pound for dairy herds and less than El 1,462 for beef herds, but with a range from 229 pound to 103,817 pound. The main cost was the slaughter of reactor cattle. For the majority of the farmers, the compensation payments seemed to meet most of the costs of their breakdowns, although a majority was still left with net losses.

Comparative costs of the commercial process in different construction procurement methods

The commercial process in construction projects is an expensive and highly variable overhead. Collaborative working practices carry many benefits, which are widely disseminated, but little information is available about their costs. Transaction Cost Economics is a theoretical framework that seeks explanations for why there are firms and how the boundaries of firms are defined through the “make-or-buy” decision. However, it is not a framework that offers explanations for the relative costs of procuring construction projects in different ways. The idea that different methods of procurement will have characteristically different costs is tested by way of a survey. The relevance of transaction cost economics to the study of commercial costs in procurement is doubtful. The survey shows that collaborative working methods cost neither more nor less than traditional methods. But the benefits of collaboration mean that there is a great deal of enthusiasm for collaboration rather than competition.

On the welfare costs of business-cycle fluctuations and economic-growth variation in the 20th century

Lucas (1987) has shown a surprising result in business-cycle research: the welfare cost of business cycles are very small. Our paper has several original contributions. First, in computing welfare costs, we propose a novel setup that separates the effects of uncertainty stemming from business-cycle fluctuations and economic-growth variation. Second, we extend the sample from which to compute the moments of consumption: the whole of the literature chose primarily to work with post-WWII data. For this period, actual consumption is already a result of counter-cyclical policies, and is potentially smoother than what it otherwise have been in their absence. So, we employ also pre-WWII data. Third, we take an econometric approach and compute explicitly the asymptotic standard deviation of welfare costs using the Delta Method. Estimates of welfare costs show major differences for the pre-WWII and the post-WWII era. They can reach up to 15 times for reasonable parameter values -β=0.985, and ∅=5. For example, in the pre-WWII period (1901-1941), welfare cost estimates are 0.31% of consumption if we consider only permanent shocks and 0.61% of consumption if we consider only transitory shocks. In comparison, the post-WWII era is much quieter: welfare costs of economic growth are 0.11% and welfare costs of business cycles are 0.037% - the latter being very close to the estimate in Lucas (0.040%). Estimates of marginal welfare costs are roughly twice the size of the total welfare costs. For the pre-WWII era, marginal welfare costs of economic-growth and business- cycle fluctuations are respectively 0.63% and 1.17% of per-capita consumption. The same figures for the post-WWII era are, respectively, 0.21% and 0.07% of per-capita consumption.

On the welfare costs of business-cycle fluctuations and economic-growth variation in the 20th century

Lucas(1987) has shown a surprising result in business-cycle research: the welfare cost of business cycles are very small. Our paper has several original contributions. First, in computing welfare costs, we propose a novel setup that separates the effects of uncertainty stemming from business-cycle uctuations and economic-growth variation. Second, we extend the sample from which to compute the moments of consumption: the whole of the literature chose primarily to work with post-WWII data. For this period, actual consumption is already a result of counter-cyclical policies, and is potentially smoother than what it otherwise have been in their absence. So, we employ also pre-WWII data. Third, we take an econometric approach and compute explicitly the asymptotic standard deviation of welfare costs using the Delta Method. Estimates of welfare costs show major diferences for the pre-WWII and the post-WWII era. They can reach up to 15 times for reasonable parameter values = 0:985, and = 5. For example, in the pre-WWII period (1901-1941), welfare cost estimates are 0.31% of consumption if we consider only permanent shocks and 0.61% of consumption if we consider only transitory shocks. In comparison, the post-WWII era is much quieter: welfare costs of economic growth are 0.11% and welfare costs of business cycles are 0.037% the latter being very close to the estimate in Lucas (0.040%). Estimates of marginal welfare costs are roughly twice the size of the total welfare costs. For the pre-WWII era, marginal welfare costs of economic-growth and business-cycle uctuations are respectively 0.63% and 1.17% of per-capita consumption. The same gures for the post-WWII era are, respectively, 0.21% and 0.07% of per-capita consumption.

An analysis of maritime transport and its costs for the Caribbean

Includes bibliography

Response to comment on "Using ecological thresholds to evaluate the costs and benefits of set-asides in a biodiversity hotspot"

Finney claims that we did not include transaction costs while assessing the economic costs of a set-aside program in Brazil and that accounting for them could potentially render large payments for environmental services (PES) projects unfeasible. We agree with the need for a better understanding of transaction costs but provide evidence that they do not alter the feasibility of the set-aside scheme we proposed.