13,856 research outputs found
Prospects of searching for composite resonances at the LHC and beyond
Composite Higgs models predict the existence of resonances. We study in
detail the collider phenomenology of both the vector and fermionic resonances,
including the possibility of both of them being light and within the reach of
the LHC. We present current constraints from di-boson, di-lepton resonance
searches and top partner pair searches on a set of simplified benchmark models
based on the minimal coset , and make projections for the reach of
the HL-LHC. We find that the cascade decay channels for the vector resonances
into top partners, or vice versa, can play an important role in the
phenomenology of the models. We present a conservative estimate for their reach
by using the same-sign di-lepton final states. As a simple extrapolation of our
work, we also present the projected reach at the 27 TeV HE-LHC and a 100 TeV
collider.Comment: 61 pages, 13 figures; accepted version of JHE
Asymptotic Correction Schemes for Semilocal Exchange-Correlation Functionals
Aiming to remedy the incorrect asymptotic behavior of conventional semilocal
exchange-correlation (XC) density functionals for finite systems, we propose an
asymptotic correction scheme, wherein an exchange density functional whose
functional derivative has the correct (-1/r) asymptote can be directly added to
any semilocal density functional. In contrast to semilocal approximations, our
resulting exchange kernel in reciprocal space exhibits the desirable
singularity of the type O(-1/q^2) as q -> 0, which is a necessary feature for
describing the excitonic effects in non-metallic solids. By applying this
scheme to a popular semilocal density functional, PBE [J. P. Perdew, K. Burke,
and M. Ernzerhof, Phys. Rev. Lett. 77, 3865 (1996)], the predictions of the
properties that are sensitive to the asymptote are significantly improved,
while the predictions of the properties that are insensitive to the asymptote
remain essentially the same as PBE. Relative to the popular model XC potential
scheme, our scheme is significantly superior for ground-state energies and
related properties. In addition, without loss of accuracy, two closely related
schemes are developed for the efficient treatment of large systems.Comment: 7 pages, 2 figures, 2 tables, supplementary material not include
Policy Optimization with Model-based Explorations
Model-free reinforcement learning methods such as the Proximal Policy
Optimization algorithm (PPO) have successfully applied in complex
decision-making problems such as Atari games. However, these methods suffer
from high variances and high sample complexity. On the other hand, model-based
reinforcement learning methods that learn the transition dynamics are more
sample efficient, but they often suffer from the bias of the transition
estimation. How to make use of both model-based and model-free learning is a
central problem in reinforcement learning. In this paper, we present a new
technique to address the trade-off between exploration and exploitation, which
regards the difference between model-free and model-based estimations as a
measure of exploration value. We apply this new technique to the PPO algorithm
and arrive at a new policy optimization method, named Policy Optimization with
Model-based Explorations (POME). POME uses two components to predict the
actions' target values: a model-free one estimated by Monte-Carlo sampling and
a model-based one which learns a transition model and predicts the value of the
next state. POME adds the error of these two target estimations as the
additional exploration value for each state-action pair, i.e, encourages the
algorithm to explore the states with larger target errors which are hard to
estimate. We compare POME with PPO on Atari 2600 games, and it shows that POME
outperforms PPO on 33 games out of 49 games.Comment: Accepted at AAAI-1
Consumer Demand for Ahi Poke (Raw Tuna Salad) in Hawaii
Ahi poke (raw tuna salad) has significant role in Hawaii culture and economy. A consumer survey in Hawaii was used to examine consumers’ purchasing intentions of ahi poke. A censored analysis was conducted to analyze the demand and tie with various consumer characteristics. Results show that many consumer eat ahi poke frequently and different consumer profiles will lead to large differences in their demand. Information obtained in study may help producers and retailers to better target their marketing strategies and increase sales.Ahi Poke, Demand, Hawaii, Tobit, Agribusiness, Agricultural and Food Policy, Consumer/Household Economics, Demand and Price Analysis, Marketing, Q13, D12,
The Difficult Case of Crystallization and Structure Solution for the ParC55 Breakage-Reunion Domain of Topoisomerase IV from Streptococcus pneumoniae
BACKGROUND: Streptococcus pneumoniae is the major cause of community-acquired pneumonia and is also associated with bronchitis, meningitis, otitis and sinusitis. The emergence and increasing prevalence of resistance to penicillin and other antibiotics has led to interest in other anti-pneumonococcal drugs such as quinolones that target the enzymes DNA gyrase and topoisomerase IV. During crystallization and in the avenues to finding a method to determine phases for the structure of the ParC55 breakage-reunion domain of topoisomerase IV from Streptococcus pneumoniae, obstacles were faced at each stage of the process. These problems included: majority of the crystals being twinned, either non-diffracting or exhibiting a high mosaic spread. The crystals, which were grown under conditions that favoured diffraction, were difficult to flash-freeze without loosing diffraction. The initial structure solution by molecular replacement failed and the approach proved to be unviable due to the complexity of the problem. In the end the successful structure solution required an in-depth data analysis and a very detailed molecular replacement search. METHODOLOGY/PRINCIPAL FINDINGS: Crystal anti-twinning agents have been tested and two different methods of flash freezing have been compared. The fragility of the crystals did not allow the usual method of transferring the crystals into the heavy atom solution. Consequently, it was necessary to co-crystallize in the presence of the heavy atom compound. The multiple isomorphous replacement approach was unsuccessful because the 7 cysteine mutants which were engineered could not be successfully derivatized. Ultimately, molecular replacement was used to solve the structure by sorting through a large number of solutions in space group P1 using CNS. CONCLUSIONS/SIGNIFICANCE: The main objective of this paper is to describe the obstacles which were faced and overcome in order to acquire data sets on such difficult crystals and determine phases for successful structure solution
Wonder woman: the first animation movie of a hero or a re-make of a female universe hero?
Actas del Segundo Congreso Internacional de Historia y Cine organizado por el Instituto de Cultura y Tecnología Miguel de Unamuno y celebrado del 9 al 11 de septiembre de 2010 en la Universidad Carlos III de MadridA análise do DVD Wonder Woman é o ponto de partida e o centro deste ensaio que pode nos fornecer alguns valiosos e variados aspectos não apenas em qual situação esta personagem se encontra atualmente no mundo dos quadrinhos mas também, possivelmente, como o mais conhecido e representativo símbolo feminino neste universo das HQ‟s, como no nosso. Neste caso e, considerando minha pesquisa sobre a origem, evolução e revolução da Mulher-Maravilha e das mulheres, nos últimos setenta anos, o DVD possibilita uma investigação sobre sua aparição em outros suportes midiático.La análisis del DVD La Mujer Maravilla es el punto de partida y el centro de este ensayo que puede proporcionar algunos valiosos y variados aspectos no solamente en lo referente a la situación en la que se encuentra actualmente este personaje en el mundo de los comics, sino también, en cuanto a su ubicación en el universo de los HQs y en el nuestro propio.
En este caso, y teniendo en cuenta mi investigación sobre la origen, evolución y revolución de la Mujer Maravilla y de las mujeres en los últimos setenta años, el DVD permite la investigación de su aparición en otros suportes midiáticos o medios de comunicación.The analysis of the DVD Wonder Woman is the starting point and the core in this essay that could provide us some valuable and multiple aspects not only where that female character is actually placed in the comic world as well as, probably, as the most known and representative female symbol in this universe and also in ours. In this case, and considering my research about the origin, evolution and revolution of Wonder Woman and the women in the last seventy years, makes possible to us to take the investigation over her appearance in another media platform.Publicad
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