5,565 research outputs found
Are Marine Protected Areas in the Turks and Caicos Islands ecologically or economically valuable?
Marine Protected Areas (MPAs) are often advocated by ecologists as a method of conserving valuable fish stocks while ensuring the integrity of ecological processes in the face of increasing anthropogenic disturbance. In the Turks and Caicos Islands there is little evidence that current MPAs are ecologically beneficial but there are indications that boundary changes may enhance queen conch and finfish production. Implementing boundary changes usually requires political will and, hence, quantifiable economic benefits. Assessing the value of reef fish is particularly important because they are potentially valuable for consumptive and nonconsumptive purposes. We demonstrate the nonconsumptive economic value of increased Nassau grouper size and abundance to the dive tourism industry through a paired comparison conjoint survey of visiting divers. Our results suggest that accounting for the non-consumptive economic value of increased Nassau grouper abundance and size may have a large impact on the economic viability of ecologically functional MPAs
Nonmarket Economic Valuation and "The Economistâs Fallacy"
ABSTRACT: It is important that noneconomists understand and consider three key points regarding the use of economic cost-benefit analysis. First, economists undertaking applied cost-benefit analyses use expected values by necessity in forward-looking models. Second, economists tally changes in economic value, comparing âwith â and âwithout â investment scenarios, using producer and consumer surplus. Third, marginal changes in the ânonmarket â components of consumer surplus can, and should, be quantified in monetary terms and included in evaluations whenever possible. These three factors highlight the need for multidisciplinary research on complex problems relating public investments to the social, cultural, health, and environmental impacts of those investments
Utility of electronic patient records for evaluating stroke secondary prevention in primary care
Collisions of low-energy antiprotons with molecular hydrogen: ionization, excitation and stopping power
A time-dependent coupled-channel approach was used to calculate ionization,
excitation, and energy-loss cross sections as well as energy spectra for
antiproton and proton collisions with molecular hydrogen for impact energies 8
keV < E < 4000 keV.Comment: 4 pages, 4 figures, conference LEAP0
Self Calibration of Tomographic Weak Lensing for the Physics of Baryons to Constrain Dark Energy
Numerical studies indicate that uncertainties in the treatment of baryonic
physics can affect predictions for shear power spectra at a level that is
significant for forthcoming surveys such as DES, SNAP, and LSST.
Correspondingly, we show that baryonic effects can significantly bias dark
energy parameter measurements. Eliminating such biases by neglecting
information in multipoles beyond several hundred leads to weaker parameter
constraints by a factor of approximately 2 to 3 compared with using information
out to multipoles of several thousand. Fortunately, the same numerical studies
that explore the influence of baryons indicate that they primarily affect power
spectra by altering halo structure through the relation between halo mass and
mean effective halo concentration. We explore the ability of future weak
lensing surveys to constrain both the internal structures of halos and the
properties of the dark energy simultaneously as a first step toward self
calibrating for the physics of baryons. This greatly reduces parameter biases
and no parameter constraint is degraded by more than 40% in the case of LSST or
30% in the cases of SNAP or DES. Modest prior knowledge of the halo
concentration relation greatly improves even these forecasts. Additionally, we
find that these surveys can constrain effective halo concentrations near
m~10^14 Msun/h and z~0.2 to better than 10% with shear power spectra alone.
These results suggest that inferring dark energy parameters with measurements
of shear power spectra can be made robust to baryonic effects and may
simultaneously be competitive with other methods to inform models of galaxy
formation. (Abridged)Comment: 18 pages, 11 figures. Minor changes reflecting referee's comments.
Results and conclusions unchanged. Accepted for publication in Physical
Review
T-cell immune adaptor SKAP1 regulates the induction of collagen-induced arthritis in mice
SKAP1 is an immune cell adaptor that couples the T-cell receptor with the âinside-outâ signalling pathway for LFA-1 mediated adhesion in T-cells. A connection of SKAP1 to the regulation of an autoimmune disorder has not previously been reported. In this study, we show that Skap1-deficient (skap1-/-) mice are highly resistant to the induction of collagen-induced arthritis (CIA), both in terms of incidence or severity. Skap1-/- T-cells were characterised by a selective reduction in the presence IL-17+ (Th17) in response to CII peptide and a marked reduction of joint infiltrating T-cells in Skap1-/- mice. SKAP1 therefore represents a novel connection to Th17 producing T-cells and is new potential target in the therapeutic intervention in autoimmune and inflammatory diseases
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