7,316 research outputs found
From Type-II Triply Degenerate Nodal Points and Three-Band Nodal Rings to Type-II Dirac Points in Centrosymmetric Zirconium Oxide
Using first-principles calculations, we report that ZrO is a topological
material with the coexistence of three pairs of type-II triply degenerate nodal
points (TNPs) and three nodal rings (NRs), when spin-orbit coupling (SOC) is
ignored. Noticeably, the TNPs reside around Fermi energy with large linear
energy range along tilt direction (> 1 eV) and the NRs are formed by three
strongly entangled bands. Under symmetry-preserving strain, each NR would
evolve into four droplet-shaped NRs before fading away, producing distinct
evolution compared with that in usual two-band NR. When SOC is included, TNPs
would transform into type-II Dirac points while all the NRs have gaped.
Remarkably, the type-II Dirac points inherit the advantages of TNPs: residing
around Fermi energy and exhibiting large linear energy range. Both features
facilitate the observation of interesting phenomena induced by type-II
dispersion. The symmetry protections and low-energy Hamiltonian for the
nontrivial band crossings are discussed.Comment: 7 pages, 5 figures, J. Phys. Chem. Lett. 201
A meta-analysis of efficacy and safety of doripenem for treating bacterial infections
AbstractObjectiveThe aim of this article is to compare the efficacy and safety of doripenem for bacterial infections.MethodsWe included six randomized clinical trials identified from PubMed and Embase up to July 31, 2014. The included trials compared efficacy and safety of doripenem for complicated intra-abdominal infections, complicated urinary tract infection, nosocomial pneumonia, and acute biliary tract infection. The meta-analysis was carried on by the statistical software of Review Manager, version 5.2.ResultsCompared with empirical antimicrobial agents on overall treatment efficacy, doripenem was associated with similar clinical and microbiological treatment success rates (for the clinical evaluable population, odds ratio [OR]=1.26, 95% confidence interval [CI] 0.93β1.69, p=0.13; for clinical modified intent-to-treatment population, OR=0.88, 95% CI 0.55β1.41, p=0.60; for microbiology evaluable population, OR=1.16, 95% CI 0.90β1.50, p=0.26; for microbiological modified intent-to-treatment (m-mITT), OR=0.98, 95% CI 0.81β1.20, p=0.87). We compared incidence of adverse events and all-cause mortality to analyze treatment safety. The outcomes suggested that doripenem was similar to comparators in terms of incidence of adverse events and all-cause mortality on modified intent-to-treatment population (for incidence of AEs, OR=1.10, 95% CI 0.90β1.35, p=0.33; for all-cause mortality, OR=1.08, 95% CI 0.77β1.51, p=0.67). In nosocomial pneumonia and ventilator-associated pneumonia treatment, doripenem was not inferior to other antibacterial agents in terms of efficacy and safety.ConclusionFrom this meta-analysis, we can conclude that doripenem is as valuable and well-tolerated than empirical antimicrobial agents for complicated intra-abdominal infections, complicated urinary tract infection, acute biliary tract infection and nosocomial pneumonia treatment
Learning Multi-Level Information for Dialogue Response Selection by Highway Recurrent Transformer
With the increasing research interest in dialogue response generation, there
is an emerging branch formulating this task as selecting next sentences, where
given the partial dialogue contexts, the goal is to determine the most probable
next sentence. Following the recent success of the Transformer model, this
paper proposes (1) a new variant of attention mechanism based on multi-head
attention, called highway attention, and (2) a recurrent model based on
transformer and the proposed highway attention, so-called Highway Recurrent
Transformer. Experiments on the response selection task in the seventh Dialog
System Technology Challenge (DSTC7) show the capability of the proposed model
of modeling both utterance-level and dialogue-level information; the
effectiveness of each module is further analyzed as well
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