2,071 research outputs found
Conditional cash and in-kind transfers increase household total and food consumption in poor rural communities in Mexico
Gobernabilidad en Santa Cruz de la Sierra: Pautas para mayor transparencia y democracia local
A partir de los años ochenta se inició una nueva etapa democrática en Bolivia,
después de quince años de alternar entre gobiernos dictatoriales y constitucionales. La
profundización de la democracia fue prolongada (1978-1982), costosa, lenta y complicada.
El desarrollo de las democracias locales, como parte del proceso general, constituyó un
paso importante en esta consolidación y estuvo marcada por la aprobación de leyes que
promueven la descentralización y la participación popular, tendientes a fortalecer la
institucionalidad pública y a mejorar la calidad de vida de los ciudadanos, con una
distribución más equitativa de los recursos financieros administrados bajo el régimen de
vigilancia y control social. El proceso estuvo matizado por problemas de legitimidad y
gobernabilidad. Una vez superados los unos se presentaron otros, generando un debate
permanente y cambiante sobre el tema
A Cylindrical GEM Inner Tracker for the BESIII experiment at IHEP
The Beijing Electron Spectrometer III (BESIII) is a multipurpose detector
that collects data provided by the collision in the Beijing Electron Positron
Collider II (BEPCII), hosted at the Institute of High Energy Physics of
Beijing. Since the beginning of its operation, BESIII has collected the world
largest sample of J/{\psi} and {\psi}(2s). Due to the increase of the
luminosity up to its nominal value of 10^33 cm-2 s-1 and aging effect, the MDC
decreases its efficiency in the first layers up to 35% with respect to the
value in 2014. Since BESIII has to take data up to 2022 with the chance to
continue up to 2027, the Italian collaboration proposed to replace the inner
part of the MDC with three independent layers of Cylindrical triple-GEM (CGEM).
The CGEM-IT project will deploy several new features and innovation with
respect the other current GEM based detector: the {\mu}TPC and analog readout,
with time and charge measurements will allow to reach the 130 {\mu}m spatial
resolution in 1 T magnetic field requested by the BESIII collaboration. In this
proceeding, an update of the status of the project will be presented, with a
particular focus on the results with planar and cylindrical prototypes with
test beams data. These results are beyond the state of the art for GEM
technology in magnetic field
A model to explain angular distributions of and decays into and
BESIII data show a particular angular distribution for the decay of the
and mesons into the hyperons
and . More in details the angular distribution of
the decay exhibits an opposite trend
with respect to that of the other three channels: , and
. We define a model to explain the
origin of this phenomenon.Comment: 6 pages, 7 figures, to be published in Chinese Physics
The Minimum-Uncertainty Squeezed States for for Atoms and Photons in a Cavity
We describe a six-parameter family of the minimum-uncertainty squeezed states
for the harmonic oscillator in nonrelativistic quantum mechanics. They are
derived by the action of corresponding maximal kinematical invariance group on
the standard ground state solution. We show that the product of the variances
attains the required minimum value 1/4 only at the instances that one variance
is a minimum and the other is a maximum, when the squeezing of one of the
variances occurs. The generalized coherent states are explicitly constructed
and their Wigner function is studied. The overlap coefficients between the
squeezed, or generalized harmonic, and the Fock states are explicitly evaluated
in terms of hypergeometric functions. The corresponding photons statistics are
discussed and some applications to quantum optics, cavity quantum
electrodynamics, and superfocusing in channeling scattering are mentioned.
Explicit solutions of the Heisenberg equations for radiation field operators
with squeezing are found.Comment: 27 pages, no figures, 174 references J. Phys. B: At. Mol. Opt. Phys.,
Special Issue celebrating the 20th anniversary of quantum state engineering
(R. Blatt, A. Lvovsky, and G. Milburn, Guest Editors), May 201
Measurement of proton electromagnetic form factors in in the energy region 2.00-3.08 GeV
The process of is studied at 22 center-of-mass
energy points () from 2.00 to 3.08 GeV, exploiting 688.5~pb of
data collected with the BESIII detector operating at the BEPCII collider. The
Born cross section~() of is
measured with the energy-scan technique and it is found to be consistent with
previously published data, but with much improved accuracy. In addition, the
electromagnetic form-factor ratio () and the value of the
effective (), electric () and magnetic () form
factors are measured by studying the helicity angle of the proton at 16
center-of-mass energy points. and are determined with
high accuracy, providing uncertainties comparable to data in the space-like
region, and is measured for the first time. We reach unprecedented
accuracy, and precision results in the time-like region provide information to
improve our understanding of the proton inner structure and to test theoretical
models which depend on non-perturbative Quantum Chromodynamics
Observation of the -Annihilation Decay and Evidence for
We report on the observation of the -annihilation decay and the evidence for with a data sample corresponding to an integrated luminosity of 3.19
fb collected with the BESIII detector at the center-of-mass energy
GeV. We obtain the branching fractions
and , respectively
Observation of in
Using a sample of events recorded with
the BESIII detector at the symmetric electron positron collider BEPCII, we
report the observation of the decay of the charmonium state
into a pair of mesons in the process
. The branching fraction is measured for the first
time to be , where the first uncertainty is
statistical, the second systematic and the third is from the uncertainty of
. The mass and width of the are
determined as MeV/ and
MeV.Comment: 13 pages, 6 figure
Protein sequence and structure: Is one more fundamental than the other?
We argue that protein native state structures reside in a novel "phase" of
matter which confers on proteins their many amazing characteristics. This phase
arises from the common features of all globular proteins and is characterized
by a sequence-independent free energy landscape with relatively few low energy
minima with funnel-like character. The choice of a sequence that fits well into
one of these predetermined structures facilitates rapid and cooperative
folding. Our model calculations show that this novel phase facilitates the
formation of an efficient route for sequence design starting from random
peptides.Comment: 7 pages, 4 figures, to appear in J. Stat. Phy
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