1,307 research outputs found

    Measuring the value of life: Exploring a new method for deriving the monetary value of a QALY

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    Economic evaluations of new health technologies now typically produce an incremental cost per Quality Adjusted Life Year (QALY) value. The QALY is a measure of health benefit that combines length of life with quality of life, where quality of life is assessed on a scale where zero represents a health state equivalent to being dead and one represents full health. The challenge for decision makers, such as the Treasury, is to determine the appropriate size of the healthcare budget. Bodies such as the National Institute for Health and Clinical Excellent (NICE) in the U.K. must then determine how much they can afford to pay for a gain of one QALY, while operating under this fixed budget. While there is no fixed cost-effectiveness threshold and each intervention is assessed on a case by case basis, under normal circumstances the threshold will not be below £20,000 and not above £30,000 per QALY. Recent research has sought to determine the monetary value individuals place on a QALY to inform the size of the healthcare budget and the level of the cost-effectiveness threshold. This research has predominantly used Willingness to Pay (WTP) approaches. However, WTP has a number of known problems, most notably its insensitivity to scope. In this paper we present an alternative approach to estimating the monetary value of a QALY (MVQ), which is based upon a Time Trade Off (TTO) exercise of income with health held constant at perfect health. We present the methods and theory underlying this experimental approach and some results from an online feasibility study in the Netherlands

    The impact of losses in income due to ill health: does the EQ-5D reflect lost earnings?

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    Two key questions in the context of UK health policy are: do the published preference indices for EQ-5D reflect the impact of lost earnings? Are we currently implicitly including indirect costs in our analyses? It is crucial to investigate whether or not individuals take into account any possible impact of lost income in health state valuation exercises. If respondents do consider income effects, and these considerations change valuations, then these effects would need to be excluded both under the current NICE reference case, or where productivity costs are included in the numerator to avoid double counting. This study adapts the study design used to generate population value sets for EQ-5D, as first used in the Measurement and Valuation of Health (MVH) Study, and carries out valuations of hypothetical EQ-5D states using Time Trade Off (TTO) exercises through an online survey administered in the Netherlands. Furthermore, this study uses a number of different TTO questions to explore the impact of losses in income on the valuation of hypothetical health states, and to determine the relationship between income and health.EQ-5D; time trade-off; health-related loss of income

    Hydroxyl radicals maintain the self-cleansing capacity of the troposphere

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    International audienceBillions of tons natural and anthropogenic gases are released and subsequently removed from the troposphere each year. Photochemical reactions, initiated by hydroxyl (OH) radicals, oxidise most gases to products which are more easily removed by precipitation and dry deposition at the Earth's surface. Since human-induced pollution emissions strongly affect OH formation and loss, large global changes in OH concentrations are possible. The available evidence as reviewed here, however, indicates that global mean OH has changed relatively little in the past century. Depletion of OH by reactive carbon gases has been compensated by increased OH formation by nitrogen oxides, an act of "inadvertent geo-engineering". Analyses of global mean OH for the past 2.5 decades, however, partly based on methyl chloroform measurements, are ambiguous. Especially the OH trend in the 1990s based on these analyses is at odds with present understanding. Since the discrepancy is dominated by the uncertainty in methyl chloroform emission estimates, improvements of source inventories and model analyses, combined with continued high precision methyl chloroform measurements, will help resolve this problem

    Eastern Asian emissions of anthropogenic halocarbons deduced from aircraft concentration data

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    The Montreal Protocol restricts production of ozone-depleting halocarbons worldwide. Enforcement of the protocol has relied mainly on annual government statistics of production and consumption of these compounds (bottom-up approach). We show here that aircraft observations of halocarbon:CO enhancement ratios on regional to continental scales can be used to infer halocarbon emissions, providing independent verification of the bottom-up approach. We apply this top-down approach to aircraft observations of Asian outflow from the TRACE-P mission over the western Pacific (March April 2001) and derive emissions from eastern Asia (China, Japan, and Korea). We derive an eastern Asian carbon tetrachloride (CCl ) source of 21.5 Gg yr , several-fold larger than previous estimates and amounting to 30% of the global budget for this gas. Our emission estimate for CFC-11 from eastern Asia is 50% higher than inventories derived from manufacturing records. Our emission estimates for methyl chloroform (CH ) and CFC-12 are in agreement with existing inventories. For halon 1211 we find only a strong local source originating from the Shanghai area. Our emission estimates for the above gases result in a 40% increase in the ozone depletion potential (ODP) of Asian emissions relative to previous estimates, corresponding to a 10% global increase in ODP

    Detection of doxorubicin-induced apoptosis of leukemic T-lymphocytes by laser tweezers Raman spectroscopy

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    Laser tweezers Raman spectroscopy (LTRS) was used to acquire the Raman spectra of leukemic T lymphocytes exposed to the chemotherapy drug doxorubicin at different time points over 72 hours. Changes observed in the Raman spectra were dependent on drug exposure time and concentration. The sequence of spectral changes includes an intensity increase in lipid Raman peaks, followed by an intensity increase in DNA Raman peaks, and finally changes in DNA and protein (phenylalanine) Raman vibrations. These Raman signatures are consistent with vesicle formation, cell membrane blebbing, chromatin condensation, and the cytoplasm of dead cells during the different stages of drug-induced apoptosis. These results suggest the potential of LTRS as a real-time single cell tool for monitoring apoptosis, evaluating the efficacy of chemotherapeutic treatments, or pharmaceutical testing

    Can crop residues provide fuel for future transport? Limited global residue bioethanol potentials and large associated land, water and carbon footprints

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    Bioethanol production from non-crop based lignocellulosic material has reached the commercial scale and is advocated as a possible solution to decarbonize the transport sector. This study evaluates how much presently used transport related fossil fuels can be replaced with lignocellulosic bioethanol using crop residues, calculates greenhouse gas emission savings, and determines lignocellulosic bioethanol's land, water, and carbon footprints. We estimate global bioethanol production potential from 123 crop residues in 192 countries and 20 territories under different environmental constraints (optimistic and realistic sustainable potentials) versus no constraints (theoretical potential) on residue availability. Previous studies on global bioethanol production potential from lignocellulosic material focused on one or few biomass feedstocks, and excluded (un)constrained residue availability scenarios. Our results suggest the global net lignocellulosic bioethanol output ranges from 7.1 to 34.0 EJ per annum replacing between 7% and 31% of oil products for transport yielding relative emission savings of 338 megatonne (Mt; 70%) to 1836 Mt (79%). Emission savings range from 4% to 23% of total transport emissions in the realistic sustainable versus theoretical potential. Land, water and carbon footprints of net bioethanol vary between potentials, countries/territories, and feedstocks, but overall exceed footprints of conventional bioethanol. Averaged footprints range between 0.14 and 0.24 m2 land per megajoule (MJ−1), 74–120 L water MJ−1, and 28–44 g CO2 equivalent MJ−1, with smaller footprints in the theoretical potential caused by the exclusion of secondary residues and low price of alternative biomass chains in the sustainable potential

    Patchy Amphiphilic Dendrimers Bind Adenovirus and Control Its Host Interactions and in Vivo Distribution

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    The surface of proteins is heterogeneous with sophisticated but precise hydrophobic and hydrophilic patches, which is essential for their diverse biological functions. To emulate such distinct surface patterns on macromolecules, we used rigid spherical synthetic dendrimers (polyphenylene dendrimers) to provide controlled amphiphilic surface patches with molecular precision. We identified an,. I optimal spatial arrangement of these patches on certain dendrimers that enabled their interaction with human adenovirus 5 (Ads). Patchy dendrimers bound to the surface of Ads formed a synthetic polymer corona that greatly altered various host interactions of Ads as well as in vivo distribution. The dendrimer corona (1) improved the ability of Ad5-derived gene transfer vectors to transduce cells deficient for the primary Ad5 cell membrane receptor and (2) modulated the binding of Ads to blood coagulation factor X, one of the most critical virus host interactions in the bloodstream. It significantly enhanced the transduction efficiency of Ad5 while also protecting it from neutralization by natural antibodies and the complement system in human whole blood. Ads with a synthetic dendrimer corona revealed profoundly altered in vivo distribution, improved transduction of heart, and dampened vector sequestration by liver and spleen. We propose the design of bioactive polymers that bind protein surfaces solely based on their amphiphilic surface patches and protect against a naturally occurring protein corona, which is highly attractive to improve Ad5-based in vivo gene therapy applications

    Quasi One-Dimensional Spin Fluctuations in YBa(2)Cu(3)O(6+x)

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    We study the spin fluctuation of the oxygen deficient planes of YBa(2)Cu(3)O(6+x). The Cu-O chains that constitute these planes are described by a model that includes antiferromagnetic interactions between spins and Kondo-like scattering of oxygen holes. The spectrum of magnetic excitations shows the presence of incommensurate dynamic fluctuations along the direction of the chains. The presence of itinerant holes is responsible for the existence of important differences between the spin dynamics of this system and that of a quasi-one-dimensional localized antiferromagnet. We comment on the possibility of experimental observation of these fluctuations.Comment: 22 pages, REVTEX, 3 figures, to appear in PRB55 (1May 1997

    Three Years of Δ14CO2 Observations from Maize Leaves in the Netherlands and Western Europe

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    Atmospheric Δ14CO2 measurements are useful to investigate the regional signals of anthropogenic CO2 emissions, despite the currently scarce observational network for Δ14CO2. Plant samples are an easily attainable alternative, which have been shown to work well as a qualitative measure of the atmospheric Δ14CO2 signals integrated over the time a plant has grown. Here, we present the 14C analysis results for 89 individual maize (Zea mays) plant samples from 51 different locations that were gathered in the Netherlands in the years 2010 to 2012, and from western Germany and France in 2012. We describe our sampling strategy and results, and include a comparison to a model simulation of the Δ14CO2 that would be accumulated in each plant over a growing season. Our model simulates the Δ14CO2 signatures in good agreement with observed plant samples, resulting in a root-mean-square deviation (RMSD) of 3.30‰. This value is comparable to the measurement uncertainty, but still relatively large (20–50%) compared to the total signal. It is also comparable to the spread in Δ14CO2 values found across multiple plants from a single site, and to the spread found when averaging across larger regions. We nevertheless find that both measurements and model capture the large-scale (>100 km) regional Δ14CO2 gradients, with significant observation-model correlations in all three countries in which we collected samples. The modeled plant results suggest that the largest gradients found in the Netherlands and Germany are associated with emissions from energy production and road traffic, while in France, the 14CO2 enrichment from nuclear sources dominates in many samples. Overall, the required model-based interpretation of plant samples adds additional uncertainty to the already relatively large measurement uncertainty in Δ14CO2, and we suggest that future fossil fuel monitoring efforts should prioritize other strategies such as direct atmospheric sampling of CO2 and Δ14CO2
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