370 research outputs found
Concepts for a multi-criteria sustainability assessment of a new more biobased economy in rural production landscapes
This study presents a new approach to model the biophysical potentials for increased biomass harvest in Denmark, and a multi-criteria sustainability assessment of the socio-economic and environmental effects of different scenarios for such increased production and new biobased economy in rural landscapes. Thereby the results serve as input to the ongoing productivism â post-productivism debate related to rural spaces in Europe.
Empirical results from a case study of large scale conversion to biorefenery technologies, aiming to increase the total Danish harvest of biomass by 10 million tonnes via the conversion to new types of crop production and land management, is used as an example, and will be related to the common conceptual model presented by the workshop convenors, and a so called âTraffic-lightâ multi-criteria sustainability assessment scheme introduced and exemplified in the present paper. The aim is to contextualize how the problems in relation to the concrete scenario results can be considered with the landscape as the meeting basis, and used as input for a discussion of innovative models for future farming systems, landscape research and management
Microsatellite Markers for Red Drum, Sciaenops ocellatus
Polymerase chain reaction (PCR) primers are reported for 68 nuclear-encoded microsatellites developed during the past several years from genomic libraries of red drum (Sciaenops ocellatus). All 68 microsatellites were tested for reproducibility and polymorphism on a sample of five to 12 red drum; 60 of the microsatellites were found to be polymorphic. Estimates of observed and expected heterozygosity (gene diversity) and tests of conformity of genotypes to Hardy-Weinberg equilibrium were carried out for a subset of 31 microsatellites on a larger sample of 45 adults provided by Texas Parks and Wildlife. Levels of allelic and gene diversity were average relative to values observed for marine and anadromous fishes. The set of genetic markers should be useful for a variety of studies, including monitoring and assessment of red drum stock enhancement
Strong coupling constant from decay within renormalization scheme invariant treatment
We extract a numerical value for the strong coupling constant \alpha_s from
the \tau-lepton decay rate into nonstrange particles. A new feature of our
procedure is the explicit use of renormalization scheme invariance in
analytical form in order to perform the actual analysis in a particular
renormalization scheme. For the reference coupling constant in the
\MSsch-scheme we obtain \alpha_s(M_\tau)= 0.3184 \pm 0.0060_{exp} which
corresponds to \al_s(M_Z)= 0.1184 \pm 0.0007_{exp} \pm 0.0006_{hq mass}. This
new numerical value is smaller than the standard value from -data quoted
in the literature and is closer to \al_s(M_Z)-values obtained from high energy
experiments.Comment: 8 page
Resummation of the hadronic tau decay width with the modified Borel transform method
A modified Borel transform of the Adler function is used to resum the
hadronic tau decay width ratio. In contrast to the ordinary Borel transform,
the integrand of the Borel integral is renormalization--scale invariant. We use
an ansatz which explicitly accounts for the structure of the leading infrared
renormalon. Further, we use judiciously chosen conformal transformations for
the Borel variable, in order to map sufficiently away from the origin the other
ultraviolet and infrared renormalon singularities. In addition, we apply Pade
approximants for the corresponding truncated perturbation series of the
modified Borel transform, in order to further accelerate the convergence.
Comparing the results with the presently available experimental data on the tau
hadronic decay width ratio, we obtain . These predictions
virtually agree with those of our previous resummations where we used ordinary
Borel transforms instead.Comment: 32 pages, 2 eps-figures, revtex; minor changes in the formulations; a
typo in Eq.(47) corrected; version as appearing in Phys. Rev.
The moonlighting peroxiredoxin-glutaredoxin in Neisseria meningitidis binds plasminogen via a C-terminal lysine residue and contributes to survival in a whole blood model
© 2019 Elsevier Ltd Neisseria meningitidis is a human-restricted bacterium that can invade the bloodstream and cross the blood-brain barrier resulting in life-threatening sepsis and meningitis. Meningococci express a cytoplasmic peroxiredoxin-glutaredoxin (Prx5-Grx) hybrid protein that has also been identified on the bacterial surface. Here, recombinant Prx5-Grx was confirmed as a plasminogen (Plg)-binding protein, in an interaction which could be inhibited by the lysine analogue Δ-aminocapronic acid. rPrx5-Grx derivatives bearing a substituted C-terminal lysine residue (rPrx5-GrxK244A), but not the active site cysteine residue (rPrx5-GrxC185A) or the sub-terminal rPrx5-GrxK230A lysine residue, exhibited significantly reduced Plg-binding. The absence of Prx5-Grx did not significantly reduce the ability of whole meningococcal cells to bind Plg, but under hydrogen peroxide-mediated oxidative stress, the N. meningitidis Îpxn5-grx mutant survived significantly better than the wild-type or complemented strains. Significantly, using human whole blood as a model of meningococcal bacteremia, it was found that the N. meningitidis Îpxn5-grx mutant had a survival defect compared with the parental or complemented strain, confirming an important role for Prx5-Grx in meningococcal pathogenesis
Scalar Field Dark Matter
This work is a review of the last results of research on the Scalar Field
Dark Matter model of the Universe at cosmological and at galactic level. We
present the complete solution to the scalar field cosmological scenario in
which the dark matter is modeled by a scalar field with the scalar
potential and the
dark energy is modeled by a scalar field , endowed with the scalar
potential , which together compose the 95% of the total
matter energy in the Universe. The model presents successfully deals with the
up to date cosmological observations, and is a good candidate to treat the dark
matter problem at the galactic level.Comment: 11 pagez, 5 figures, REVTeX. To appear in proceedings of the
``Mexican Meeting on Exact Solutions and Scalar Fields in Gravity '', in
honour of Heinz Dehnen's 65th Birthday and Dietrich Kramer's 60th Birthday.
Mexico D.F., Mexico, in press. More info at
http://www.fis.cinvestav.mx/~siddh/PHI
Calculations of binding energies and masses of heavy quarkonia using renormalon cancellation
We use various methods of Borel integration to calculate the binding ground
energies and masses of b-bbar and t-tbar quarkonia. The methods take into
account the leading infrared renormalon structure of the hard+soft part of the
binding energies E(s), and of the corresponding quark pole masses m_q, where
the contributions of these singularities in M(s) = 2 m_q + E(s) cancel.
Beforehand, we carry out the separation of the binding energy into its
hard+soft and ultrasoft parts. The resummation formalisms are applied to
expansions of m_q and E(s) in terms of quantities which do not involve
renormalon ambiguity, such as MSbar quark mass, and alpha_s. The
renormalization scales are different in calculations of m_q, E(s) and E(us).
The MSbar mass of b quark is extracted, and the binding energies of t-tbar and
the peak (resonance) energies for (t+tbar) production are obtained.Comment: 23 pages, 8 double figures, revtex4; the version to appear in
Phys.Rev.D; extended discussion between Eqs.(25) and (26); the paragraph
between Eqs.(32) and (33) is new and explains the numerical dependence of the
residue parameter on the factorization scale; several new references were
added; acknowledgments were modified; the numerical results are unchange
âStepping away from the computer and into the sweats': The construction and negotiation of exercise identities in a Norwegian public company
While research has found that a developed exercise identity enables individuals to view exercise participation as self- reinforcing, the social barriers to such exercise identity development and participation have not been fully addressed. The subsequent aim of this study was to explore some of the social complexities at play in terms of how company employees construct and manage their exercise identities within a work place setting. A case-study method was used to address the research issue over a nine-month period. The case to be studied included a sample of 72 employees from a Norwegian public company who participated in an on-going work-based exercise programme called âExercise for allâ. The principal means of data collection comprised participant observation, individual interviews and exercise logbooks. The data were subject to inductive analysis. The primary barriers to exercise participation included high levels of social comparison in a competitive working context, particularly in relation to âcompetent colleaguesâ, and feelings of guilt associated with partaking in ârecreationalâ activities during work hours. Strategies engaged with to overcome and negotiate such obstacles included justifying participation through a health-related discourse, and constructing a more distinct âworker-exerciserâ identity
Categorizing Different Approaches to the Cosmological Constant Problem
We have found that proposals addressing the old cosmological constant problem
come in various categories. The aim of this paper is to identify as many
different, credible mechanisms as possible and to provide them with a code for
future reference. We find that they all can be classified into five different
schemes of which we indicate the advantages and drawbacks.
Besides, we add a new approach based on a symmetry principle mapping real to
imaginary spacetime.Comment: updated version, accepted for publicatio
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