731 research outputs found
Payment for Watershed Services: Opportunities and Realities
Many nations have found that regulatory approaches to land and water management have a limited impact. An alternative is to create incentives for sound management - under mechanisms known as payments for ecosystem services. It is a simple idea: people who look after ecosystems that benefit others should be recognised and rewarded. In the case of watersheds, downstream beneficiaries of wise upstream land and water use should compensate the stewards. To be effective, these 'payments for watershed services' must cover the costs of watershed management. In developing countries, they might also aid local development and reduce poverty. But new research shows that the problems in watersheds are complex and not easily solved. Payments for watershed services do not guarantee poverty reduction and cannot replace the best aspects of regulation
Fair Deals for Watershed Services: Lessons from a Multi-country Action-learning Project
Payments for ecosystem services make good sense. In the case of watershed ecosystems, downstream beneficiaries of wise upstream land and water stewardship should compensate these upstream stewards. These 'payments for watershed services' (PWS) should contribute to the costs of watershed management and, if upstream communities are also characterised by poverty, these payments should contribute to local development and poverty reduction as well. Debates about both conservation and development have seen a wave of excitement about payments for watershed services in recent years. But on the ground an equivalent surge of action is harder to see. IIED and its partners have been building on earlier international case study work to set up new PWS schemes - to 'learn by doing' and to improve our understanding of the opportunities and the challenges.This report is about the complex business of trying to put a simple conservation and development idea into practice. The idea is that watershed degradation in developing countries might be better tackled than it currently is if downstream beneficiaries of wise land use in watershed areas paid for these benefits. There are some examples around the world of this idea being put into practice - this report reviews these and describes what happened when teams in six developing countries set about exploring how the idea works on the ground
Wildlife research and development
A research paper on wildlife research and development in Zimbabwe.Wildlife as legitimate, viable and competitive land-use is now well established in several southern African countries. Zimbabwe played a leading and pioneering role in developing wildlife as a land-use in both commercial and communal farming sectors and by 1990 it covered 22 per cent of the country (Cumming, 1991a). By the late 1980s, the wildlife-based tourism industry was the fastest growing sector of the economy and ranked fourth in its contribution to gross domestic product. An important feature of the wildlife sector was that it generated wealth, and particularly foreign exchange earnings, from marginal lands and provided incentives to conserve the country’s wildlife heritage and biodiversity.203 This is possible because, unlike meat, milk and hides, wildlife’s main revenue earning products are service-based and only loosely coupled to rainfall and plant production. Importantly, extensive wildlife production systems maintain ecosystem services and retain options for future development
An abrupt extinction in the Middle Permian (Capitanian) of the Boreal Realm (Spitsbergen) and its link to anoxia and acidification
The controversial Capitanian (Middle Permian, 262 Ma) extinction event is only known from equatorial latitudes, and consequently its global extent is poorly resolved. We demonstrate that there were two, severe extinctions amongst brachiopods in northern Boreal latitudes (Spitsbergen) in the Middle to Late Permian, separated by a recovery phase. New age dating of the Spitsbergen strata (belonging to the Kapp Starostin Formation), using strontium isotopes and d13C trends and comparison with better-dated sections in Greenland, suggests that the first crisis occurred in the Capitanian. This age assignment indicates that this Middle Permian extinction is manifested at higher latitudes. Redox proxies (pyrite framboids and trace metals) show that the Boreal crisis coincided with an intensification of oxygen depletion, implicating anoxia in the extinction scenario. The widespread and near-total loss of carbonates across the Boreal Realm also suggests a role for acidification in the crisis. The recovery interval saw the appearance of new brachiopod and bivalve taxa alongside survivors, and an increased mollusk dominance, resulting in an assemblage reminiscent of younger Mesozoic assemblages. The subsequent end-Permian mass extinction terminated this Late Permian radiation
Sterile neutrinos in tau lepton decays
We study possible contributions of heavy sterile neutrinos to the
decays . From the experimental
upper bounds on their rates we derive new constraints on the
mixing in the mass region MeV. We discuss
cosmological and astrophysical status of in this mass region and
compare our constraints with those recently derived by the NOMAD collaboration.Comment: 17 pages, 2 figure
Renin as a biomarker of acute kidney Injury and mortality in children with severe malaria or sickle cell disease
Background: Globally, a very high percentage of acute kidney injury (AKI) occurs in low- and middle-income countries (LMICs) where late recognition contributes to increased mortality. There are challenges with using existing biomarkers of AKI in LMICs. Emerging evidence suggests renin may serve as a biomarker of kidney injury that can overcome limitations in creatinine-based diagnostics.
Methods: Two study populations in Uganda were assessed. Cohort #1 was a two-site, prospective cohort study enrolling 600 children with severe malaria (SM). Cohort #2 was a prospective cohort study enrolling 185 children with sickle cell disease (SCD) hospitalized with a vaso-occlusive crisis. Plasma or serum renin concentrations were measured in both cohorts of children at the time of hospital admission using Luminex® (Luminex Corporation, Austin, Texas, United States) or enzyme-linked immunosorbent assay (ELISA), respectively. We assessed the ability of renin to discriminate between children with or without AKI and between children who survived and children who died using receiver operating characteristic curves.
Results: In both cohorts, renin concentrations were strongly associated with AKI and mortality. Renin was able to discriminate between children with or without AKI with an area under the curve (AUC) of 0.70 (95%CI, 0.65-0.74) in children with SM and 0.72 (95%CI, 0.6co3-0.81) in children with SCD. Renin was able to discriminate between children who survived and children who died with an AUC of 0.73 (95%CI, 0.63- 0.83) in children with SM and 0.94 (95%CI, 0.89-0.99) in children with SCD. In Cohort #2, we compared renin against urine neutrophil gelatinase-associated lipocalin (NGAL) as the leading biomarker of AKI, and it had comparable performance in discriminating AKI and predicting mortality.
Conclusions: In two independent populations of children at risk of AKI with key differences in the etiology of kidney injury, renin was strongly associated with AKI and mortality and had moderate to good diagnostic performance to predict mortality
The nature of assembly bias - II. Halo spin
We study an assembly-type bias parametrized by the dimensionless spin
parameter that affects massive structures. In numerical simulations higher spin
haloes are more strongly clustered than lower spin haloes of equal mass. We
detect a difference of over a 30 per cent in the clustering strength for dark
matter haloes of 10^13-10^14 Msun, which is similar to the result of Bett et
al. We explore whether the dependence of clustering strength on halo spin is
removed if we apply the redefinition of overdensity peak height proposed by
Lacerna & Padilla (Paper I) obtained using assembly ages. We find that this is
not the case due to two reasons. Firstly, only a few objects of low-virial mass
are moved into the mass range where the spin introduces an assembly bias after
using this redefinition. Secondly, this formalism does not alter the mass of
massive objects. We then repeat the process of finding the redefined peak
height of Paper I but using the spin. In this case, the new masses show no
spin-related assembly bias but they introduce a previously absent assembly bias
with respect to relative age. From this result, we conclude that the
assembly-type bias with respect to the halo spin has a different origin than
with respect to assembly age. The former may be due to the material from
filaments, which is accreted by massive haloes, that is enhanced in
high-density environments, thus causing more extreme spin values without
significantly changing the formation age of the halo. In addition, high-mass
objects may correspond, in some cases, to a different peak height than that
suggested by their mass in numerical simulations, providing a possible
explanation for the assembly bias with respect to spin. (abridged)Comment: 5 pages, 5 figures. Accepted for publication in MNRAS letter
The nature of assembly bias - I. Clues from a LCDM cosmology
We present a new proxy for the overdensity peak height for which the
large-scale clustering of haloes of a given mass does not vary significantly
with the assembly history. The peak height, usually taken to be well
represented by the virial mass, can instead be approximated by the mass inside
spheres of different radii, which in some cases can be larger than the virial
radius and therefore include mass outside the individual host halo. The sphere
radii are defined as r = delta_t + log_10(M_vir/M_nl), where delta_t is
the age relative to the typical age of galaxies hosted by haloes with virial
mass M_vir, M_nl is the non-linear mass, and =0.2 and =-0.02 are the free
parameters adjusted to trace the assembly bias effect. Note that depends on
both halo mass and age. In this new approach, some of the objects which were
initially considered low-mass peaks belong to regions with higher
overdensities. At large scales, i.e. in the two-halo regime, this model
properly recovers the simple prescription where the bias responds to the height
of the mass peak alone, in contrast to the usual definition (virial mass) that
shows a strong dependence on additional halo properties such as formation time.
The dependence on the age in the one-halo term is also remarkably reduced. The
population of galaxies whose "peak height" changes with this new definition
consists mainly of old stellar populations and are preferentially hosted by
low-mass haloes located near more massive objects. The latter is in agreement
with recent results which indicate that old, low-mass haloes would suffer
truncation of mass accretion by nearby larger haloes or simply due to the high
density of their surroundings, thus showing an assembly bias effect. The change
in mass is small enough that the Sheth et al. (2001) mass function is still a
good fit to the resulting distribution of new masses.Comment: 13 pages, 10 figures, submitted to MNRAS, comments welcom
TermWise: A CAT-tool with Context-Sensitive Terminological Support
Abstract Increasingly, large bilingual document collections are being made available online, especially in the legal domain. This type of Big Data is a valuable resource that specialized translators exploit to search for informative examples of how domain-specific expressions should be translated. However, general purpose search engines are not optimized to retrieve previous translations that are maximally relevant to a translator. In this paper, we report on the TermWise project, a cooperation of terminologists, corpus linguists and computer scientists, that aims to leverage big online translation data for terminological support to legal translators at the Belgian Federal Ministry of Justice. The project developed dedicated knowledge extraction algorithms and a server-based tool to provide translators with the most relevant previous translations of domain-specific expressions relative to the current translation assignment. The functionality is implemented as an extra database, a Term&Phrase Memory, that is meant to be integrated with existing Computer Assisted Translation tools. In the paper, we give an overview of the system, give a demo of the user interface, we present a user-based evaluation by translators and discuss how the tool is part of the general evolution towards exploiting Big Data in translation
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