As a generic property, all substances transfer heat through microscopic collisions of constituent particles
. A solid conducts heat through both transverse and longitudinal acoustic phonons, but a ...liquid employs only longitudinal vibrations
. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here, we report liquid-like thermal conduction observed in the crystalline AgCrSe
. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive, and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. These microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.
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IJS, KISLJ, NUK, SBMB, UL, UM, UPUK
There is a growing interest in the effectiveness of mindfulness meditation for sleep disturbed populations. Our study sought to evaluate the effect of mindfulness meditation interventions on sleep ...quality. To assess for relative efficacy, comparator groups were restricted to specific active controls (such as evidenced‐based sleep treatments) and nonspecific active controls (such as time/attention‐matched interventions to control for placebo effects), which were analyzed separately. From 3303 total records, 18 trials with 1654 participants were included. We determined the strength of evidence using four domains (risk of bias, directness of outcome measures, consistency of results, and precision of results). At posttreatment and follow‐up, there was low strength of evidence that mindfulness meditation interventions had no effect on sleep quality compared with specific active controls (ES 0.03 (95% CI –0.43 to 0.49)) and (ES –0.14 (95% CI –0.62 to 0.34)), respectively. Additionally, there was moderate strength of evidence that mindfulness meditation interventions significantly improved sleep quality compared with nonspecific active controls at postintervention (ES 0.33 (95% CI 0.17–0.48)) and at follow‐up (ES 0.54 (95% CI 0.24–0.84)). These preliminary findings suggest that mindfulness meditation may be effective in treating some aspects of sleep disturbance. Further research is warranted.
There is a growing interest in the effectiveness of mindfulness meditation for sleep disturbed populations. Our study sought to evaluate the effect of mindfulness meditation interventions on sleep quality. To assess for relative efficacy, comparator groups were restricted to specific active controls, such as evidenced‐based sleep treatments and nonspecific active controls, such as time/attention‐matched interventions to control for placebo effects, which were analyzed separately.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor νover ¯_{e} inverse β decay candidates observed over 1958 days ...of data collection. The installation of a flash analog-to-digital converter readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic ^{9}Li and ^{8}He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative νover ¯_{e} rates and energy spectra among detectors yields sin^{2}2θ_{13}=0.0856±0.0029 and Δm_{32}^{2}=(2.471_{-0.070}^{+0.068})×10^{-3} eV^{2} assuming the normal hierarchy, and Δm_{32}^{2}=-(2.575_{-0.070}^{+0.068})×10^{-3} eV^{2} assuming the inverted hierarchy.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
We previously demonstrated that pretreatment quantitative anti–hepatitis B core protein (qAnti-HBc) levels can predict the treatment response for both interferon and nucleoside analogue therapy, but ...the characteristics of qAnti-HBc during chronic hepatitis B virus (HBV) infection remain poorly understood. To understand this issue, the qAnti-HBc levels were evaluated in individuals with past HBV infection, occult HBV infection and chronic HBV infection in the immune tolerance phase, immune clearance phase, low-replicative phase and hepatitis B e antigen (HBeAg)-negative hepatitis phase. Individuals with hepatitis B surface antigen (n = 598, 3.74 ± 0.90 log10 IU/mL) had significantly higher (p < 0.001, approximately 1000-fold) serum qAnti-HBc levels than those who had occult HBV, and serum qAnti-HBc levels were significantly higher in the occult HBV group than in the past HBV infection group (p < 0.001). qAnti-HBc levels were positively correlated with alanine aminotransferase levels (R = 0.663, p < 0.001), and subjects with an abnormal alanine aminotransferase level had a higher qAnti-HBc level (p < 0.001). Serum qAnti-HBc level varied in different phases of HBV infection, as determined by host immune status. Serum qAnti-HBc level is strongly associated with hepatitis activity in subjects with chronic HBV infection.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
Introduction
Functional dyspepsia (FD) is diagnosed based on self-reported symptoms and negative upper gastrointestinal endoscopic findings. The Rome criteria were not adopted as a ...diagnostic instrument in clinical guidelines due to their complexity. Different guidelines used relatively simple symptom assessment schemes with contents that vary significantly. A previously evaluated short Reference Standard may serve as a more standardised tool for guidelines. We evaluated its diagnostic accuracy against the Rome IV criteria in a cross-sectional study in Hong Kong.
Methods
A total of 220 dyspeptic patients sampled consecutively from a tertiary hospital and the community completed the Rome IV diagnostic questionnaire, which was translated into Cantonese-Chinese, and the Reference Standard. Sensitivity, specificity, positive and negative likelihood ratios (LRs), and area under the receiver operating characteristics curve (AUC), with 95% confidence intervals (CIs), were calculated.
Results
Among the participants, 160 (72.7%) fulfilled the Reference Standard with negative upper gastrointestinal endoscopic results. The Reference Standard identified patients with Rome IV-defined FD with 91.1% (95% CI 82.6%–96.4%) sensitivity and 37.6% (95% CI 29.6%–46.1%) specificity. The positive and negative LRs were 1.46 (95% CI 1.26–1.69) and 0.24 (95% CI 0.11–0.49), respectively. The AUC value was 0.64 (95% CI 0.59–0.69).
Conclusions
The Reference Standard can rule out patients without Rome IV-defined FD. It may be used as an initial screening tool for FD in settings where the use of the Rome IV criteria is impractical. It may also provide a uniform definition and diagnostic rule for future updates of clinical guidelines.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We present Data Releases 4 and 5 of the quasar catalog from the quasar survey by the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST), which includes quasars observed between 2015 ...September and 2017 June. There are a total of 19,253 quasars identified by visual inspections of the spectra. Among them, 11,458 were independently discovered by LAMOST, in which 3296 were reported by the SDSS DR12 and DR14 quasar catalog after our survey began, while the remaining 8162 are new discoveries of LAMOST. We provide the emission line measurements for H , Hβ, Mg ii, and/or C iv for 18,100 quasars. Since LAMOST does not have absolute flux calibration information, we obtain the monochromatic continuum luminosities by fitting the SDSS photometric data using the quasar spectra, and then estimate the black hole masses. The catalog and spectra for these quasars are available online. This is the third installment in the series of LAMOST quasar surveys that has released spectra for ∼43,000 quasars to date. There are 24,772 independently discovered quasars, 17,128 of which are newly discovered. In addition to this great supplement to the new quasar discoveries, LAMOST has also provided a large database (overlapped with SDSS) for investigating quasar spectral variability and discovering unusual quasars, including changing-look quasars, with ongoing and upcoming large surveys.
We demonstrate, both theoretically and experimentally, that cation vacancy can be the origin of ferromagnetism in intrinsic dilute magnetic semiconductors. The vacancies can be controlled to tune the ...ferromagnetism. Using Li-doped ZnO as an example, we found that while Li itself is nonmagnetic, it generates holes in ZnO, and its presence reduces the formation energy of Zn vacancy, and thereby stabilizes the zinc vacancy. Room temperature ferromagnetism with p type conduction was observed in pulsed laser deposited ZnO:Li films with certain doping concentration and oxygen partial pressure.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Shock acceleration is considered one of the most important mechanisms for the acceleration of astrophysical energetic particles. In this work, we calculate the trajectories of a large number of test ...charged particles accurately in a parallel shock with magnetic turbulence. We investigate the time evolution of the accelerated particle energy spectrum in the downstream of the shock, in order to understand the acceleration mechanism of energetic particles. From simulation results we obtain power-law energy spectra with a bend-over energy, E0, increasing with time. With the particle mean acceleration time and mean momentum change during each cycle of the shock crossing from the diffusive shock acceleration model (following Drury), a time-dependent differential equation for the maximum energy, Eacc, of particles accelerated at the shock can be approximately obtained. We assume the theoretical bend-over energy as Eacc. It is found that the bend-over energy from simulations agrees well with the theoretical bend-over energy using the nonlinear diffusion theory, NLGCE-F, in contrast to that using the classic quasi-linear theory.
With the aim of gathering temporal trends on bacterial epidemiology and resistance from multiple laboratories in China, the CHINET surveillance system was organized in 2005. Antimicrobial ...susceptibility testing was carried out according to a unified protocol using the Kirby-Bauer method or automated systems. Results were analyzed according to Clinical and Laboratory Standards Institute (CLSI) 2014 definitions. Between 2005 and 2014, the number of bacterial isolates ranged between 22 774 and 84 572 annually. Rates of extended-spectrum β-lactamase production among Escherichia coli isolates were stable, between 51.7 and 55.8%. Resistance of E. coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, piperacillin/tazobactam and cefoperazone/sulbactam decreased with time. Carbapenem resistance among K. pneumoniae isolates increased from 2.4 to 13.4%. Resistance of Pseudomonas aeruginosa strains against all of antimicrobial agents tested including imipenem and meropenem decreased with time. On the contrary, resistance of Acinetobacter baumannii strains to carbapenems increased from 31 to 66.7%. A marked decrease of methicillin resistance from 69% in 2005 to 44.6% in 2014 was observed for Staphylococcus aureus. Carbapenem resistance rates in K. pneumoniae and A. baumannii in China are high. Our results indicate the importance of bacterial surveillance studies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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