7,629 research outputs found
Possible duality violations in tau decay and their impact on the determination of alpha_s
We discuss the issue of duality violations in hadronic tau decay. After
introducing a physically motivated ansatz for duality violations, we estimate
their possible size by fitting this ansatz to the tau experimental data
provided by the ALEPH collaboration. Our conclusion is that these data do not
exclude significant duality violations in tau decay. This may imply an
additional systematic error in the value of alpha_s(m_tau), extracted from tau
decay, as large as \delta alpha_s(m_tau) \sim 0.003-0.010 .Comment: 20 pages, 4 figures. Minor fixes in the Appendi
An example of resonance saturation at one loop
We argue that the large-Nc expansion of QCD can be used to treat a Lagrangian
of resonances in a perturbative way. As an illustration of this we compute the
L_10 coupling of the Chiral Lagrangian by integrating out resonance fields at
one loop. Given a Lagrangian and a renormalization scheme, this is how in
principle one can answer in a concrete and unambiguous manner questions such as
at what scale resonance saturation takes place.Comment: 9 pages, 5 figures. Enlarged discussion, results unchanged. To be
published in Phys. Rev.
Capacidades y mujer emprendedora
Este artÃculo muestra la incorporación de la mujer a la formación de capital humano, su
situación laboral y su situación como directiva en España, y propone un conjunto de
teorÃas o enfoques que contribuyen al examen de la situación de la mujer. Por otra parte
examina la literatura de referencia sobre los aspectos polÃticos y de concepción de la
mujer en los paÃses capitalistas, asà como sus condiciones laborales en relación con la
equidad (dimensión ética y moral) y la productividad (dimensión económica). Distinguir
ambas dimensiones clarifica las polÃticas públicas y de empresa que conviene [email protected]; [email protected]
BiometrÃa del Estornino Negro (Sturnus unicolor Temm,) en el centro-oeste de la PenÃnsula Ibérica
Analytic Reconstruction of heavy-quark two-point functions at O(\alpha_s^3)
Using a method previously developed, based on the Mellin-Barnes transform, we
reconstruct the two-point correlators in the vector, axial, scalar and
pseudoscalar channels from the Taylor expansion at q^2=0, the threshold
expansion at q^2=4m^2 and the OPE at q^2\rightarrow -\infty, where m is the
heavy quark mass. The reconstruction is analytic and systematic and is
controlled by an error function which becomes smaller as more terms in those
expansions are known.Comment: 19 pages, 11 figure
Duality Violation and the K --> pi pi Electroweak Penguin Operator Matrix Elements from Hadronic Tau Decays
We discuss a preliminary study of the impact of duality violations on
extractions from tau decay data of the D=6 VEVs which determine chiral limit
Standard Model K-->pi pi matrix elements of the electroweak penguin operators.Comment: 4 pages, 5 figures, prepared for the Proceedings of the 11th Particle
and Nuclear Intersections Conference (PANIC 2011), Boston, USA, July 24-29,
201
Unified protocol for the transdiagnostic treatment of emotional disorders in group format in spain: results of a noninferiority randomized controlled trial at 15 months after treatment onset
Evidence-based psychological treatments (EBPT) are an effective and efficient solution for the treatment of emotional disorders (EDs). However, their implementation and dissemination are not yet widespread. The Unified Protocol for Transdiagnostic Treatment of EDs (UP), applied in a group format, could be an effective option to be implemented in specialized public mental health services in Spain. The sample consisted of 533 users of public specialized mental health centers (77.3% women), with a mean age of 42.0 years (), who were randomized to the UP in group format condition () or treatment as usual (specific cognitive behavioral therapy for each disorder in individual format, ). Assessments were performed at preintervention (T1) and at 3, 6, 9 and 15 months after treatment onset (T2, T3, T4, and T5, respectively). The results showed a main effect of time in both conditions for all primary outcomes () and no statistically significant TimeCondition interaction. Similarly, the noninferiority tests showed that UP results were statistically noninferior compared to TAU. Effect sizes for psychological variables were higher in the UP condition at T5, even though the differences were not statistically significant. Statistically significant differences () in the evolution of the diagnostic criteria and comorbidity were found, with the highest percentage of patients no longer meeting main and secondary diagnosis criteria in the UP condition at all assessment moments (except for secondary diagnosis at T3). The results showed statistically significant differences in treatment retention between conditions at T5, being the UP condition the one with less dropouts. Finally, participants in the group UP condition showed high satisfaction with the treatment. The UP is an EBPT that has been shown to be effective when applied in groups and may represent an efficient option for its implementation in public mental health services in Spain
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
A relativistic chiral quark model for pseudoscalar emission from heavy mesons
The amplitudes for one-pion mediated transitions between heavy meson excited
states are obtained in the framework of the relativistic chiral quark model.
The effective coupling constants to pions and the decay widths of excited heavy
mesons with l<=2 for non-radially excited, and the l=0 radially excited mesons
are presented for both charmed and beauty mesons. We also discuss the allowed
decays of strange excited heavy mesons by emission of a K-meson.Comment: 20 pages, revte
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