The Price Premium for Organic Babyfood: A Hedonic Analysis

The price premium associated with organic babyfood is estimated by applying a hedonic model to price and characteristic data for babyfood products collected in two cities: Raleigh, North Carolina, and San Jose, California. The price per ounce of babyfood is modeled as a function of a number of babyfood and store characteristics. The estimated organic price premium is generally equal to 3 cents to 4 cents per ounce. To the extent this premium reflects consumer willingness to pay to reduce pesticide exposures, it could be used to infer values for reduced dietary exposures to pesticide residues for babies.babyfood, hedonic analysis, organic foods, Demand and Price Analysis,

Willingness to Pay for Mortality Risk Reductions: Does Latency Matter?

Using results from two contingent valuation surveys conducted in Canada and the U.S., we explore the effect of a latency period on willingness to pay (WTP) for reduced mortality risk using both structural and reduced form approaches. We find that delaying the time at which the risk reduction occurs by 10 to 30 years reduces WTP by more than half for respondents in both samples aged 40 to 60 years. Additionally, we estimate implicit discount rates equal to 8% for Canada and 4.5% for the U.S. – both well within the range established previously in the literature.Value of a statistical life, Mortality risks, Benefit-cost analyris

Valuing mortality reductions in India : a study of compensating wage differentials

Conducting cost-benefit analyses of health and safety regulations requires placing a dollar value on reductions in health risks, including the risk of death. In the United States, mortality risks are often valued using compensating-wage differentials. These differentials measure what a worker would have to be paid to accept a small increase in his risk of death-which is assumed to equal what the worker would pay to achieve a small reduction in his risk of death. The authors estimate compensating-wage differentials for risk of fatal and nonfatal injuries in India's manufacturing industry. They estimate a hedonic wage equation using the most recent Occupational Wage Survey, supplemented by data on occupational injuries from the Indian Labour Yearbook. Their estimates of compensating-wage differentials imply a value of statistical life (VSL) in India of 6.4 million to 15 million 1990 rupees (roughly $150,000 to$360,000 at current exchange rates). This number is between 20 and 48 times forgone earnings-the human capital measure of the value of reducing the risk of death. The ratio of the VSL to forgone earnings implied by the study is larger than in comparable U.S. studies but smaller than the ratio implied by the only other compensating-wage study for India (Shanmugam 1997). The latter implies a ratio of VSL to forgone earnings of 73! The authors caution that in India, as in the United States, compensating-wage differentials in the labor market may overstate what individuals would themselves pay to reduce the risk of death. They suggest using their estimates as an upper boundon willingness to pay to reduce risk of death, and forgone earnings as a lower bound.Labor Policies,Water and Industry,Public Health Promotion,Environmental Economics&Policies,Banks&Banking Reform,Banks&Banking Reform,Health Monitoring&Evaluation,Health Economics&Finance,Water and Industry,Environmental Economics&Policies

The health effects of air pollution in Delhi, India

The authors report the results of a time-series study of the impact of particulate air pollution on daily mortality in Delhi. They find: a) A positive, significant relationship between particulate pollution and daily nontraumatic deaths as well as deaths from certain causes (respiratory and cardiovascular problems) and for certain age groups. b) In general, these impacts are smaller than those estimated for other countries, where on average a 100-microgram increase in total suspended particulates (TSP) leads to a 6-percent increase in nontraumatic mortality. In Delhi, such an increase in TSP is associated with a 2.3-percent increase in deaths. c) The differences in magnitudes of the effects are most likely explained by differences in distributions of age at death and cause of death, as most deaths in Delhi occur before the age of 65 and are not attributed to causes with a strong association with air pollution. d) Although air pollution seems to have less impact on mortality counts in Delhi, the number of life-years saved per death avoided is greater in Delhi than in US cities -- because the age distribution of impacts in these two places varies. In the United States particulates have the greatest influence on daily deaths among persons 65 and older. In Delhi, they have the greatest impact in the 15-to-44 age group. That means that for each death associated with air pollution, on average more life-years would be saved in Delhi than in the United States. Large differences in the magnitude of effects do call into question the validity of the"concentration-response transfer"procedure. In that procedure, concentration-response relationships found for industrial countries are applied to cities in developing countries with little or no adjustment, to estimate the effects of pollution on daily mortality.Demographics,Public Health Promotion,Montreal Protocol,Health Monitoring&Evaluation,Air Quality&Clean Air,Health Monitoring&Evaluation,Montreal Protocol,Demographics,Environmental Economics&Policies,Health Systems Development&Reform

Approximation of the critical buckling factor for composite panels

This article is concerned with the approximation of the critical buckling factor for thin composite plates. A new method to improve the approximation of this critical factor is applied based on its behavior with respect to lamination parameters and loading conditions. This method allows accurate approximation of the critical buckling factor for non-orthotropic laminates under complex combined loadings (including shear loading). The influence of the stacking sequence and loading conditions is extensively studied as well as properties of the critical buckling factor behavior (e.g concavity over tensor D or out-of-plane lamination parameters). Moreover, the critical buckling factor is numerically shown to be piecewise linear for orthotropic laminates under combined loading whenever shear remains low and it is also shown to be piecewise continuous in the general case. Based on the numerically observed behavior, a new scheme for the approximation is applied that separates each buckling mode and builds linear, polynomial or rational regressions for each mode. Results of this approach and applications to structural optimization are presented

Diamond Surface Functionalization via Visible Light-Driven C-H Activation for Nanoscale Quantum Sensing

Nitrogen-vacancy centers in diamond are a promising platform for nanoscale nuclear magnetic resonance sensing. Despite significant progress towards using NV centers to detect and localize nuclear spins down to the single spin level, NV-based spectroscopy of individual, intact, arbitrary target molecules remains elusive. NV molecular sensing requires that target molecules are immobilized within a few nanometers of NV centers with long spin coherence time. The inert nature of diamond typically requires harsh functionalization techniques such as thermal annealing or plasma processing, limiting the scope of functional groups that can be attached to the surface. Solution-phase chemical methods can be more readily generalized to install diverse functional groups, but they have not been widely explored for single-crystal diamond surfaces. Moreover, realizing shallow NV centers with long spin coherence times requires highly ordered single-crystal surfaces, and solution-phase functionalization has not yet been shown to be compatible with such demanding conditions. In this work, we report a versatile strategy to directly functionalize C-H bonds on single-crystal diamond surfaces under ambient conditions using visible light. This functionalization method is compatible with charge stable NV centers within 10 nm of the surface with spin coherence times comparable to the state of the art. As a proof of principle, we use shallow ensembles of NV centers to detect nuclear spins from functional groups attached to the surface. Our approach to surface functionalization based on visible light-driven C-H bond activation opens the door to deploying NV centers as a broad tool for chemical sensing and single-molecule spectroscopy

High Burden of Non-Influenza Viruses in Influenza-Like Illness in the Early Weeks of H1N1v Epidemic in France

BACKGROUND: Influenza-like illness (ILI) may be caused by a variety of pathogens. Clinical observations are of little help to recognise myxovirus infection and implement appropriate prevention measures. The limited use of molecular tools underestimates the role of other common pathogens. OBJECTIVES: During the early weeks of the 2009-2010 flu pandemic, a clinical and virological survey was conducted in adult and paediatric patients with ILI referred to two French University hospitals in Paris and Tours. Aims were to investigate the different pathogens involved in ILI and describe the associated symptoms. METHODS: H1N1v pandemic influenza diagnosis was performed with real time RT-PCR assay. Other viral aetiologies were investigated by the molecular multiplex assay RespiFinder19®. Clinical data were collected prospectively by physicians using a standard questionnaire. RESULTS: From week 35 to 44, endonasal swabs were collected in 413 patients. Overall, 68 samples (16.5%) were positive for H1N1v. In 13 of them, other respiratory pathogens were also detected. Among H1N1v negative samples, 213 (61.9%) were positive for various respiratory agents, 190 in single infections and 23 in mixed infections. The most prevalent viruses in H1N1v negative single infections were rhinovirus (62.6%), followed by parainfluenza viruses (24.2%) and adenovirus (5.3%). 70.6% of H1N1v cases were identified in patients under 40 years and none after 65 years. There was no difference between clinical symptoms observed in patients infected with H1N1v or with other pathogens. CONCLUSION: Our results highlight the high frequency of non-influenza viruses involved in ILI during the pre-epidemic period of a flu alert and the lack of specific clinical signs associated with influenza infections. Rapid diagnostic screening of a large panel of respiratory pathogens may be critical to define and survey the epidemic situation and to provide critical information for patient management

A large scale hearing loss screen reveals an extensive unexplored genetic landscape for auditory dysfunction

The developmental and physiological complexity of the auditory system is likely reflected in the underlying set of genes involved in auditory function. In humans, over 150 non-syndromic loci have been identified, and there are more than 400 human genetic syndromes with a hearing loss component. Over 100 non-syndromic hearing loss genes have been identified in mouse and human, but we remain ignorant of the full extent of the genetic landscape involved in auditory dysfunction. As part of the International Mouse Phenotyping Consortium, we undertook a hearing loss screen in a cohort of 3006 mouse knockout strains. In total, we identify 67 candidate hearing loss genes. We detect known hearing loss genes, but the vast majority, 52, of the candidate genes were novel. Our analysis reveals a large and unexplored genetic landscape involved with auditory function

Combined assessment of DYRK1A, BDNF and homocysteine levels as diagnostic marker for Alzheimer’s disease

Early identification of Alzheimer’s disease (AD) risk factors would aid development of interventions to delay the onset of dementia, but current biomarkers are invasive and/or costly to assess. Validated plasma biomarkers would circumvent these challenges. We previously identified the kinase DYRK1A in plasma. To validate DYRK1A as a biomarker for AD diagnosis, we assessed the levels of DYRK1A and the related markers brain-derived neurotrophic factor (BDNF) and homocysteine in two unrelated AD patient cohorts with age-matched controls. Receiver-operating characteristic curves and logistic regression analyses showed that combined assessment of DYRK1A, BDNF and homocysteine has a sensitivity of 0.952, a specificity of 0.889 and an accuracy of 0.933 in testing for AD. The blood levels of these markers provide a diagnosis assessment profile. Combined assessment of these three markers outperforms most of the previous markers and could become a useful substitute to the current panel of AD biomarkers. These results associate a decreased level of DYRK1A with AD and challenge the use of DYRK1A inhibitors in peripheral tissues as treatment. These measures will be useful for diagnosis purposes.This work was supported by the FEANS. We acknowledge the platform accommodation and animal testing of the animal facility at the Institute Jacques-Monod (University Paris Diderot) and the FlexStation3 facility of the Functional and Adaptive Biology (BFA) LaboratoryPeer reviewe