2,839 research outputs found
Biodiversity: Its Meanings, Roles, and Status
This chapter reviews biodiversity science concepts that lead to both definitions and metrics for tracking change. Beyond its general meaning, the term âbiodiversityâ is now common in a wide range of situations, from ecology, through conservation biology, nature conservation, environmental sciences, and environmental policy. Common approaches to measuring biodiversity are outlined and its roles, state, and trends described in way that is relevant for economics. There are many perceptions of what biodiversity includes and how to measure changes over time and space. It is argued that the starting point for economic valuation must come from accounting properly for the benefits that flow from biodiversity. Included are the general categories of intrinsic and extrinsic values, ecosystem services, heritage, adaptability, and resilience, and relevant components and metrics of biodiversity for each of these are indicated, and areas where there are significant gaps in knowledge and information identified
The natural capital framework for sustainable, efficient and equitable decision making
The concept of ânatural capitalâ is gaining traction internationally as recognition grows of the central role of the natural environment in sustaining economic and social well-being. It is therefore encouraging to see the first signs of a ânatural capital approachâ to decision making being accepted within government policy processes and the private sector. However, there are multiple different understandings of this âapproachâ, many of which misuse or omit key features of its foundations in natural science and economics. To address this, we present a framework for natural capital analysis and decision making that links ecological and economic perspectives
A Comparison of Risk Exposure in Aquaculture and Agricultural Businesses
Agriculture and aquaculture have common features associated with their biological nature affecting risk exposure of the businesses. The aim of this paper is to compare risk exposure in salmon farming and agricultural enterprises in Norway by using an implicit error component model to examine the risk structure of yields, prices and economic returns at the farm level. Results indicate a higher farm-level year-to-year variability in yields, prices and economic returns in salmon farming than in agricultural enterprises. The variability in livestock enterprises was generally lower than for crop enterprises. Return on assets was highest in salmon farming with an average annual return of 9.2%. All of the agricultural farm types exhibited a negative average return on assets on average. Stochastic dominance tests of the distribution of economic returns from aquaculture and agricultural farm types showed salmon farming to be the most risk efficient alternative and salmon farming was most attractive from an investorâs perspective.Risk analysis, variability, Norway, Risk and Uncertainty,
M Giants with IGRINS II. Chemical Evolution of Fluorine at High Metallicities
The origin and evolution of fluorine in the Milky Way galaxy is still in
debate. In particular, the increase of the [F/Fe] in metal-rich stars found
from near-IR HF-lines is challenging to explain theoretically. We determine the
fluorine abundances from 50 M giants in the solar neighbourhood spanning a
broad range of metallicities (-0.9<[Fe/H]<0.25 dex). These stars are cool
enough to have an array of HF lines in the K band. We observed the stars with
the IGRINS and investigate each of ten HF molecular lines in detail. Based on a
detailed line-by-line analysis of ten HF lines, we find that the R19, R18 and
R16 lines should primarily be used for abundance analysis. The R15, R14 and R13
lines can also be used, but the trends based on these lines show increasing
dependencies with the stellar parameters. The strongest HF lines, namely R12,
R11, R9 and R7 should be avoided since the abundances from them show
significant trends with the stellar parameters, and a high sensitivity to
variations in the microturbulence, especially for coolest metal-rich stars.
This leads to a huge scatter and high fluorine abundances for supersolar
metallicity stars, not seen in the trends from the weaker lines for the same
stars. When estimating the final mean fluorine abundance trend versus
metallicity, we neglect the fluorine abundances from the four strongest lines
(R7, R9, R11 and R12) for all stars and use only those derived from R16, R18,
and R19 for the coolest metal-rich stars. We confirm the flat trend of [F/Fe]
found in other studies in the metallicity range of -1.0<[Fe/H]<0.0. We also
find a slight enhancement at supersolar metallicities (0<[Fe/H]<0.15) but we
cannot confirm the upward trend seen at [Fe/H]>0.25. We need more observations
of M giants at super solar metallicities with a spectrometer like IGRINS to
confirm if the metal-rich fluorine abundance upturn is real or not.Comment: 11 pages, 6 figures, Accepted for publication in A&
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Treatment of Tuberculosis in Complex Emergencies in Developing Countries: A Scoping Review
Almost 172 million people live in complex emergencies globally resulting from political and/or economic instability. The provision and continuity of health care in complex emergencies remain a significant challenge. Health agencies are often hesitant to implement tuberculosis programmes in particular because its treatment requires a longer commitment than most acute diseases. However, not treating tuberculosis promptly increases mortality and untreated tuberculosis further increases the incidence of tuberculosis. Given that complex emergencies are increasing globally, there is an urgent need to analyse the available evidence to improve our understanding of how best to deliver tuberculosis programmes in such settings. Using a scoping review method, we selected and analysed fifteen studies on tuberculosis programmes in complex emergencies. We found that despite the challenges, tuberculosis programmes have been successful in complex emergencies. We identified seven cross-cutting factors that were found to be important: service providers and treatment regime, training and supervision, donor support, adherence, leadership and coordination, monitoring, and government and community support. In general, programmes showed greater creativity and flexibility to adapt to the local conditions and at times, it also meant diverting from the WHO guidelines. We identify areas of further research including the need to study the effectiveness of programmes that divert from the WHO guidelines and their implication on drug resistance
Detection of Coulomb Charging around an Antidot
We have detected oscillations of the charge around a potential hill (antidot)
in a two-dimensional electron gas as a function of a perpendicular magnetic
field B. The field confines electrons around the antidot in closed orbits, the
areas of which are quantised through the Aharonov-Bohm effect. Increasing B
reduces each state's area, pushing electrons closer to the centre, until enough
charge builds up for an electron to tunnel out. This is a new form of the
Coulomb blockade seen in electrostatically confined dots. We have also studied
h/2e oscillations and found evidence for coupling of opposite spin states of
the lowest Landau level.Comment: 3 pages, 3 Postscript figures, submitted to the proceedings of
EP2DS-1
Food-Dependent Exercise-Induced Anaphylaxis: A Case Related to Chickpea Ingestion and Review
Abstract
Food-dependent exercise-induced anaphylaxis (FDEIA) is recognized as a distinct category of exercise-induced anaphylaxis (EIA) but is very likely underdiagnosed. This report describes a 41-year-old Indian woman who experienced two separate episodes of anaphylaxis while dancing after she had eaten chickpea-containing foods. The chickpea, a small legume, is a staple ingredient in culinary traditions from around the world, especially in India, the Middle East, and North Africa. Chickpea-containing dishes are also becoming more widespread in the Western world with the growing popularity of South Asian, Middle Eastern, and African cuisines. It is important to consider FDEIA in cases of unexplained anaphylaxis as reactions can occur several hours after ingesting the culprit food(s). Furthermore, no reaction occurs if a sensitized individual eats the culprit food(s) without exercising afterward; therefore, triggering foods can easily be overlooked. Current ideas on the pathophysiology, predisposing factors, workup, and treatment of FDEIA are also summarized here
Assessment of Error in Synoptic-Scale Diagnostics Derived from Wind Profiler and Radiosonde Network Data
A topic of current practical interest is the accurate characterization of the synoptic-scale atmospheric state from wind profiler and radiosonde network observations. We have examined several related and commonly applied objective analysis techniques for performing this characterization and considered their associated level of uncertainty both from a theoretical and a practical standpoint. A case study is presented where two wind profiler triangles with nearly identical centroids and no common vertices produced strikingly different results during a 43-h period. We conclude that the uncertainty in objectively analyzed quantities can easily be as large as the expected synoptic-scale signal. In order to quantify the statistical precision of the algorithms, we conducted a realistic observing system simulation experiment using output from a mesoscale model. A simple parameterization for estimating the uncertainty in horizontal gradient quantities in terms of known errors in the objectively analyzed wind components and temperature is developed from these results
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