216 research outputs found
Silenos divinos en el espejo encantado: el Coloquio de los perros y la poética vital del Quijote, II
Sensory dots, no-self, and stream-entry: The significance of buddhist contemplative development for transpersonal studies
Based on the author’s nearly 50 years of meditation, it is observed that as a given alternative state is accessed and used over the span of years, experiences and capacities within that state are not merely static but may themselves shift as a practitioner develops neuropsychologically. An ethnographer using a substance within the context of a cultural practice may gain helpful direct insights into that cultural practice, but the researcher may fail to realize that the state attained by a novice may be substantively different from that gained by an elder or shaman with years of experience in the practice. The author’s meditation led to insight that visual and other phenomenal experiences are constructed out of sensory particles, or sensory dots. This practice later led to a state in which pure awareness was aware only of itself, and to an experiential realization of the Buddhist teaching of no-self
High-Energy Cosmology: gamma rays and neutrinos from beyond the galaxy
Our knowledge of the high-energy universe is undergoing a period of rapid
change as new astronomical detectors of high-energy radiation start to operate
at their design sensitivities. Now is a boomtime for high-energy astrophysics,
with new discoveries from Swift and HESS, results from MAGIC and VERITAS
starting to be reported, the upcoming launches of the gamma-ray space
telescopes GLAST and AGILE, and anticipated data releases from IceCube and
Auger. A formalism for calculating statistical properties of cosmological
gamma-ray sources is presented. Application is made to model calculations of
the statistical distributions of gamma-ray and neutrino emission from (i)
beamed sources, specifically, long-duration GRBs, blazars, and extagalactic
microquasars, and (ii) unbeamed sources, including normal galaxies, starburst
galaxies and clusters. Expressions for the integrated intensities of faint
beamed and unbeamed high-energy radiation sources are also derived. A toy model
for the background intensity of radiation from dark-matter annihilation taking
place in the early universe is constructed. Estimates for the gamma-ray fluxes
of local group galaxies, starburst, and infrared luminous galaxies are briefly
reviewed. Because the brightest extragalactic gamma-ray sources are flaring
sources, and these are the best targets for sources of PeV -- EeV neutrinos and
ultra-high energy cosmic rays, rapidly slewing all-sky telescopes like MAGIC
and an all-sky gamma-ray observatory beyond Milagro will be crucial for optimal
science return in the multi-messenger age.Comment: 10 pages, 3 figs, accepted for publication in the Barcelona
Conference on Multimessenger Astronomy; corrected eq. 27, revised Fig. 3,
added 2 ref
Nonfactorizable contributions to decays
While the factorization assumption works well for many two-body nonleptonic
meson decay modes, the recent measurement of with
, and shows large deviation from this assumption. We
analyze the decays in the perturbative QCD approach based on
factorization theorem, in which both factorizable and nonfactorizable
contributions can be calculated in the same framework. Our predictions for the
Bauer-Stech-Wirbel parameters, and and and , are
consistent with the observed and branching ratios,
respectively. It is found that the large magnitude and the large
relative phase between and come from color-suppressed
nonfactorizable amplitudes. Our predictions for the , branching ratios can be confronted with
future experimental data.Comment: 25 pages with Latex, axodraw.sty, 6 figures and 5 tables, Version
published in PRD, Added new section 5 and reference
Overstory influences on light attenuation patterns and understory plant community diversity and composition in southern boreal forests of Quebec
We have characterized overstory light transmission, understory light levels, and plant communities in mixedwood boreal forests of northwestern Quebec with the objective of understanding how overstory light transmission interacts with composition and time since disturbance to influence the diversity and composition of understory vegetation, and, in turn, the further attenuation of light to the forest floor by the understory. Overstory light transmission differed among three forest types (aspen, mixed deciduous-conifer, and old cedar-dominated), with old forests having higher proportions of high light levels than aspen and mixed forests, which were characterized by intermediate light levels. The composition of the understory plant communities in old forests showed the weakest correlation to overstory light transmission, although those forests had the largest range of light transmission. The strongest correlation between characteristics of overstory light transmission and understory communities was found in aspen forests. Species diversity indices were consistently higher in aspen forests but showed weak relationships with overstory light transmission. Light attenuation by the understory vegetation and total height of the understory vegetation were strongly and positively related to overstory light transmission but not forest type. Therefore, light transmission through the overstory influenced the structure and function of understory plants more than their diversity and composition. This is likely due to the strong effect of the upper understory layers, which tend to homogenize light levels at the forest floor regardless of forest type. The understory plant community acts as a filter, thereby reducing light levels at the forest floor to uniformly low levels
Elimination of onchocerciasis in Africa by 2025: an ambitious target requires ambitious interventions
To achieve the elimination of onchocerciasis transmission in all African countries will entail enormous challenges, as has been highlighted by the active discussion around onchocerciasis intervention strategies and evaluation procedures in this journal.Serological thresholds for onchocerciasis elimination, adapted for the African setting, need to be established. The Onchocerciasis Technical Advisory Subgroup of the World Health Organization is currently developing improved guidelines to allow country elimination commi
Charm multiplicity and the branching ratios of inclusive charmless b quark decays in the general two-Higgs-doublet models
In the framework of general two-Higgs-doublet models, we calculate the
branching ratios of various inclusive charmless b decays by using the low
energy effective Hamiltonian including next-to-leading order QCD corrections,
and examine the current status and the new physics effects on the determination
of the charm multiplicity and semileptonic branching ratio .
Within the considered parameter space, the enhancement to the ratio due to the charged-Higgs penguins can be as large as a factor of 8 (3) in
the model III (II), while the ratio can be increased from
the standard model prediction of 2.49% to 4.91% (2.99%) in the model III (II).
Consequently, the value of and can be decreased simultaneously
in the model III. The central value of will be lowered slightly by
about 0.003, but the ratio can be reduced significantly from the
theoretical prediction of in the SM to , for GeV, respectively. We find that
the predicted and the measured now agree within roughly one
standard deviation after taking into account the effects of gluonic charged
Higgs penguins in the model III with a relatively light charged Higgs boson.Comment: 25 pages, Latex file, axodraw.sty, 6 figures. Final version to be
published in Phys.Rev.
Charmless Decays Based on the six-quark Effective Hamiltonian with Strong Phase Effects II
We provide a systematic study of charmless decays (
and denote pseudoscalar and vector mesons, respectively) based on an
approximate six-quark operator effective Hamiltonian from QCD. The calculation
of the relevant hard-scattering kernels is carried out, the resulting
transition form factors are consistent with the results of QCD sum rule
calculations. By taking into account important classes of power corrections
involving "chirally-enhanced" terms and the vertex corrections as well as weak
annihilation contributions with non-trivial strong phase, we present
predictions for the branching ratios and CP asymmetries of decays into
PP, PV and VV final states, and also for the corresponding polarization
observables in VV final states. It is found that the weak annihilation
contributions with non-trivial strong phase have remarkable effects on the
observables in the color-suppressed and penguin-dominated decay modes. In
addition, we discuss the SU(3) flavor symmetry and show that the symmetry
relations are generally respected
Flavour and Collider Interplay for SUSY at LHC7
The current 7 TeV run of the LHC experiment shall be able to probe gluino and
squark masses up to values larger than 1 TeV. Assuming that hints for SUSY are
found in the jets plus missing energy channel by the end of a 5 fb run,
we explore the flavour constraints on three models with a CMSSM-like spectrum:
the CMSSM itself, a Seesaw extension of the CMSSM, and Flavoured CMSSM. In
particular, we focus on decays that might have been measured by the time the
run is concluded, such as and . We also analyse
constraints imposed by neutral meson bounds and electric dipole moments. The
interplay between collider and flavour experiments is explored through the use
of three benchmark scenarios, finding the flavour feedback useful in order to
determine the model parameters and to test the consistency of the different
models.Comment: 44 pages, 15 figures; v3: minor corrections, added references,
updated figures. Version accepted for publicatio
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