7,127 research outputs found
Trauma-informed resilient child welfare agencies: A New England Learning Community — Summary of the work: April 2017
Mass generation for non-Abelian antisymmetric tensor fields in a three-dimensional space-time
Starting from a recently proposed Abelian topological model in (2+1)
dimensions, which involve the Kalb-Ramond two form field, we study a
non-Abelian generalization of the model. An obstruction for generalization is
detected. However we show that the goal is achieved if we introduce a vectorial
auxiliary field. Consequently, a model is proposed, exhibiting a non-Abelian
topological mass generation mechanism in D=3, that provides mass for the
Kalb-Ramond field. The covariant quantization of this model requires ghosts for
ghosts. Therefore in order to quantize the theory we construct a complete set
of BRST and anti-BRST equations using the horizontality condition.Comment: 8 pages. To appear in Physical Review
Wavelets: a powerful tool for studying rotation, activity, and pulsation in Kepler and CoRoT stellar light curves
Aims. The wavelet transform has been used as a powerful tool for treating
several problems in astrophysics. In this work, we show that the time-frequency
analysis of stellar light curves using the wavelet transform is a practical
tool for identifying rotation, magnetic activity, and pulsation signatures. We
present the wavelet spectral composition and multiscale variations of the time
series for four classes of stars: targets dominated by magnetic activity, stars
with transiting planets, those with binary transits, and pulsating stars.
Methods. We applied the Morlet wavelet (6th order), which offers high time and
frequency resolution. By applying the wavelet transform to the signal, we
obtain the wavelet local and global power spectra. The first is interpreted as
energy distribution of the signal in time-frequency space, and the second is
obtained by time integration of the local map. Results. Since the wavelet
transform is a useful mathematical tool for nonstationary signals, this
technique applied to Kepler and CoRoT light curves allows us to clearly
identify particular signatures for different phenomena. In particular, patterns
were identified for the temporal evolution of the rotation period and other
periodicity due to active regions affecting these light curves. In addition, a
beat-pattern signature in the local wavelet map of pulsating stars over the
entire time span was also detected.Comment: Accepted for publication on A&
Pesquisa com arroz de sequeiro no Estado do Acre.
Melhoramento: Introdução; Competição de cultivares de arroz de sequeiro. Rio Branco, 1976 e 1977/78; Introdução de cultivares de arroz de sequeiro. Rio Branco-Ac, 1977; Introdução e avaliação de cultivares de arroz. Rio Branco, 1979; Comportamento de cultivares e linhagens de arroz de sequeiro na microrregião Alto Purus-Acre. Rio Branco, 1978/79; Competição de cultivares internacionais de arroz. Rio Branco, 1978/79; Comportamento de cultivares de arroz irrigado sob regime de sequeiro favorecido. Rio Branco-Ac, 1980/81-1981/82; Avaliações preliminares de cultivares e linhagens de arroz de sequeiro. Rio Branco-Ac, 1982; Avaliações de genótipos de arroz de sequeiro em ensaios integrados. Rio Branco-Ac, 1980/81 - 1981/82; Publicações; Fitotecnia; Fitopatologia; Entomologia; Agradecimentos; Literatura consultada.bitstream/item/75595/1/CPAF-AC-DOC-3-84.pdfEditores: César Sabogal; José Natalino Macedo Silv
Aspects of U-duality in BLG models with Lorentzian metric 3-algebras
In our previous paper, it was shown that BLG model based on a Lorentzian
metric 3-algebra gives Dp-brane action whose worldvolume is compactified on
torus T^d (d=p-2). Here the 3-algebra was a generalized one with d+1 pairs of
Lorentzian metric generators and expressed in terms of a loop algebra with
central extensions. In this paper, we derive the precise relation between the
coupling constant of the super Yang-Mills, the moduli of T^d and some R-R flux
with VEV's of ghost fields associated with Lorentzian metric generators. In
particular, for d=1, we derive the Yang-Mills action with theta term and show
that SL(2,Z) Montonen-Olive duality is realized as the rotation of two VEV's.
Furthermore, some moduli parameters such as NS-NS 2-form flux are identified as
the deformation parameters of the 3-algebras. By combining them, we recover
most of the moduli parameters which are required by U-duality symmetry.Comment: 27 pages, v2: minor correction
Electrochemical catalytic cyclization reactions using environmentally friendly methodologies
The electrochemical intramolecular cyclisation of bromoalkoxylated derivatives 1 was carried out using Ni(II) complexes as the
catalysts in ethanol solutions by constant-current electrolysis in one-compartment cell in the absence of sacrificial anodes as an
environmentally friendly system. The reduction of the substrates proceeds via one-electron cleavage of the carbon–bromine bond to
form radical-type intermediates that undergo cyclisation to afford cyclic ethers in moderate to good yields.Fundação para a Ciência e a Tecnologia (FCT
The TARGET_TIA: A complete, flexible and sound territorial impact assessment tool
This chapter presents TARGET_TIA as a relevant and flexible Territorial Impact Assessment (TIA) methodology. TARGET_TIA was created in a context where existing ESPON TIA tools were mainly designed for assessing ex ante territorial impacts of EU directives. Hence, in view of the need to properly assess the main ex post territorial impacts of EU Cohesion Policy in several countries in a relevant and sound way, the author decided to design, test and apply his own TIA methodology, named TARGET_TIA. When compared with other existing TIA methodologies, TARGET_TIA can be used both at ex ante and ex post policy evaluation phases. In addition, it brings to the table the possibility to use counterfactual evaluation elements to allow the production of credible and sound TIA evaluation scores. Following on from its implementation in assessing the main territorial impacts of EU policies and programmes, mostly at the ex post evaluation phase, it is possible to conclude that it is a credible, flexible, easy-to-operate, cost-effective and robust TIA methodology, which can be applied to projects, programmes and policies, at all territorial levels.info:eu-repo/semantics/acceptedVersio
Abundant cyanopolyynes as a probe of infall in the Serpens South cluster-forming region
We have detected bright HC7N J = 21-20 emission toward multiple locations in
the Serpens South cluster-forming region using the K-Band Focal Plane Array at
the Robert C. Byrd Green Bank Telescope. HC7N is seen primarily toward cold
filamentary structures that have yet to form stars, largely avoiding the dense
gas associated with small protostellar groups and the main central cluster of
Serpens South. Where detected, the HC7N abundances are similar to those found
in other nearby star forming regions. Toward some HC7N `clumps', we find
consistent variations in the line centroids relative to NH3 (1,1) emission, as
well as systematic increases in the HC7N non-thermal line widths, which we
argue reveal infall motions onto dense filaments within Serpens South with
minimum mass accretion rates of M ~ 2-5 M_sun Myr^-1. The relative abundance of
NH3 to HC7N suggests that the HC7N is tracing gas that has been at densities n
~ 10^4 cm^-3, for timescales t < 1-2 x 10^5 yr. Since HC7N emission peaks are
rarely co-located with those of either NH3 or continuum, it is likely that
Serpens South is not particularly remarkable in its abundance of HC7N, but
instead the serendipitous mapping of HC7N simultaneously with NH3 has allowed
us to detect HC7N at low abundances in regions where it otherwise may not have
been looked for. This result extends the known star-forming regions containing
significant HC7N emission from typically quiescent regions, like the Taurus
molecular cloud, to more complex, active environments.Comment: 19 pages, 13 figures, accepted to MNRAS. Version with full resolution
figures available at http://www.dunlap.utoronto.ca/~friesen/Friesen_HC7N.pd
Resultados dos ensaios sul brasileiros de trigo do Rio Grande do Sul, em 1985.
bitstream/item/119646/1/FOL-02362.pdfTrabalho apresentado na XVIII Reunião da Comissão Sul Brasileira de Pesquisa de Trigo, Chapecó, 1986
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