10,627 research outputs found
Smart grid architecture for rural distribution networks: application to a Spanish pilot network
This paper presents a novel architecture for rural distribution grids. This architecture is designed to modernize traditional rural networks into new Smart Grid ones. The architecture tackles innovation actions on both the power plane and the management plane of the system. In the power plane, the architecture focuses on exploiting the synergies between telecommunications and innovative technologies based on power electronics managing low scale electrical storage. In the management plane, a decentralized management system is proposed based on the addition of two new agents assisting the typical Supervisory Control And Data Acquisition (SCADA) system of distribution system operators. Altogether, the proposed architecture enables operators to use more effectively—in an automated and decentralized way—weak rural distribution systems, increasing the capability to integrate new distributed energy resources. This architecture is being implemented in a real Pilot Network located in Spain, in the frame of the European Smart Rural Grid project. The paper also includes a study case showing one of the potentialities of one of the principal technologies developed in the project and underpinning the realization of the new architecture: the so-called Intelligent Distribution Power Router.Postprint (published version
Reunion overseas: introduced wild boars and cultivated orange trees interact in the Brazilian Atlantic forest
Little is known concerning novel interactions between species that typically
interact in their native range but, as a consequence of human activity, are also interacting out of their original
distribution under new ecological conditions. Objective: We investigate the interaction between the orange tree
and wild boar, both of which share Asian origins and have been introduced to the Americas (i.e. the overseas).
Methods: Specifically, we assessed whether i) wild boars consume orange (Citrus sinensis) fruits and seeds
in orchards adjacent to a remnant of the Atlantic Forest of Brazil, ii) the orange seeds are viable after passing
through boar’s digestive tract and iii) whether the orange tree may naturalise in the forest remnant assisted by
wild boars. Results: Our camera surveys indicated that wild boar was by far the most frequent consumer of
orange fruits (40.5 % of camera trap-days). A considerable proportion of sown orange seeds extracted from fresh
boar feces emerged seedlings (27.8 %, N = 386) under controlled greenhouse conditions. Further, 37.6 % of sown
seeds (N = 500) in the forest remnant emerged seedlings in July 2015; however, after ~4 years (March 2019)
only 9 seedlings survived (i.e. 4.8 %, N = 188). Finally, 52 sweet orange seedlings were found during surveys
within the forest remnant which is intensively used by wild boars. This study indicates a high potential of boars
to act as effective seed dispersers of the sweet orange. However, harsh competition with native vegetation and
the incidence of lethal diseases, which quickly kill sweet orange trees under non-agricultural conditions, could
seriously limit orange tree establishment in the forest. Conclusions: Our results have important implications not
only because the wild boar could be a vector of potential invasive species, but also because they disperse seeds
of some native species (e.g. the queen palm, Syagrus romanzofiana) in defaunated forests, where large native
seed dispersers are missing; thus, wild boars could exert critical ecological functions lost due to human activityinfo:eu-repo/semantics/publishedVersio
Effects of adenotonsillectomy on plasma inflammatory biomarkers in obese children with obstructive sleep apnea: A community-based study.
BackgroundObesity and obstructive sleep apnea syndrome (OSA) are highly prevalent and frequently overlapping conditions in children that lead to systemic inflammation, the latter being implicated in the various end-organ morbidities associated with these conditions.AimTo examine the effects of adenotonsillectomy (T&A) on plasma levels of inflammatory markers in obese children with polysomnographically diagnosed OSA who were prospectively recruited from the community.MethodsObese children prospectively diagnosed with OSA, underwent T&A and a second overnight polysomnogram (PSG) after surgery. Plasma fasting morning samples obtained after each of the two PSGs were assayed for multiple inflammatory and metabolic markers including interleukin (IL)-6, IL-18, plasminogen activator inhibitor-1 (PAI-1), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-9 (MMP-9), adiponectin, apelin C, leptin and osteocrin.ResultsOut of 122 potential candidates, 100 obese children with OSA completed the study with only one-third exhibiting normalization of their PSG after T&A (that is, apnea-hypopnea index (AHI) ≤1/hour total sleep time). However, overall significant decreases in MCP-1, PAI-1, MMP-9, IL-18 and IL-6, and increases in adropin and osteocrin plasma concentrations occurred after T&A. Several of the T&A-responsive biomarkers exhibited excellent sensitivity and moderate specificity to predict residual OSA (that is, AHI⩾5/hTST).ConclusionsA defined subset of systemic inflammatory and metabolic biomarkers is reversibly altered in the context of OSA among community-based obese children, further reinforcing the concept on the interactive pro-inflammatory effects of sleep disorders such as OSA and obesity contributing to downstream end-organ morbidities
Sideritis ,nolinae a new Iberian endenjie
STÉBING, O., PERIS, J.B. & FIGUEROLA, R. 1993. Sideritis molinae un nuevo endemismo ibérico. Bot. Complutensis IB: 113-121 Se describe una nueva especie del género Sideritis L. para la Flora Ibérica
The Extended Chiral Quark Model confronts QCD
We discuss the truncation of low energy effective action of QCD below the
chiral symmetry breaking (CSB) scale, including all operators of dimensionality
less or equal to 6 which can be built with quark and chiral fields. We perform
its bosonization in the scalar, pseudoscalar, vector and axial-vector channels
in the large-N_c and leading-log approximation. Constraints on the coefficients
of the effective lagrangian are derived from the requirement of Chiral Symmetry
Restoration (CSR) at energies above the CSB scale in the scalar-pseudoscalar
and vector-axial-vector channels, from matching to QCD at intermediate scales,
and by fitting some hadronic observables. In this truncation two types of
pseudoscalar states (massless pions and massive Pi'-mesons), as well as a
scalar, vector and axial-vector one arise as a consequence of dynamical chiral
symmetry breaking. Their masses and coupling constants as well as a number of
chiral structural constants are derived. A reasonable fit of all parameters
supports a relatively heavy scalar meson (quarkonium) with the mass \sim 1 GeV
and a small value of axial pion-quark coupling constant g_A \simeq 0.55.Comment: Talk at QCD99, Montpellier, July 1999, 7 pages, Late
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High Energy Theorems at Large-N
Sum rules for products of two, three and four QCD currents are derived using
chiral symmetry at infinite momentum in the large-N limit. These exact
relations among meson decay constants, axialvector couplings and masses
determine the asymptotic behavior of an infinite number of QCD correlators. The
familiar spectral function sum rules for products of two QCD currents are among
the relations derived. With this precise knowledge of asymptotic behavior, an
infinite number of large-N QCD correlators can be constructed using dispersion
relations. A detailed derivation is given of the exact large-N pion vector form
factor and forward pion-pion scattering amplitudes.Comment: 34 pages TeX and mtexsis.tex, 10 figures (uses epsf
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