5,267 research outputs found
Safety and efficacy of etomidate and propofol anesthesia in elderly patients undergoing gastroscopy: A double-blind randomized clinical study
The aim of the present study is to compare the safety, efficacy and cost effectiveness of anesthetic regimens by compound, using etomidate and propofol in elderly patients undergoing gastroscopy. A total of 200 volunteers (65–79 years of age) scheduled for gastroscopy under anesthesia were randomly divided into the following groups: P, propofol (1.5–2.0 mg/kg); E, etomidate (0.15-0.2 mg/kg); P+E, propofol (0.75–1 mg/kg) followed by etomidate (0.075-0.1 mg/kg); and E+P, etomidate (0.075-0.01 mg/kg) followed by propofol (0.75–1 mg/kg). Vital signs and bispectral index were monitored at different time points. Complications, induction and examination time, anesthesia duration, and recovery and discharge time were recorded. At the end of the procedure, the satisfaction of patients, endoscopists and the anesthetist were evaluated. The recovery (6.1±1.2 h) and discharge times (24.8±2.8 h) in group E were significantly longer compared with groups P, P+E and E+P (P<0.05). The occurrence of injection pain in group P+E was significantly higher compared with the other three groups (P<0.05). In addition, the incidence of myoclonus and post-operative nausea and vomiting were significantly higher in group P+E compared with the other three groups (P<0.05). There was no statistical difference among the four groups with regards to the patients' immediate, post-procedure satisfaction (P>0.05). Furthermore, there was no difference in the satisfaction of anesthesia, as evaluated by the anesthetist and endoscopist, among the four groups (P>0.05). The present study demonstrates that anesthesia for gastroscopy in elderly patients can be safely and effectively accomplished using a drug regimen that combines propofol with etomidate. The combined use of propofol and etomidate has unique characteristics which improve hemodynamic stability, cause minimal respiratory depression and less side effects, provide rapid return to full activity and result in high levels of satisfaction
A loss-of-function allele of OsHMA3 associated with high cadmium accumulation in shoots and grain of Japonica rice cultivars
This article is protected by copyright. All rights reserved.Peer reviewedPostprin
Duality between the deconfined quantum-critical point and the bosonic topological transition
Recently significant progress has been made in -dimensional conformal
field theories without supersymmetry. In particular, it was realized that
different Lagrangians may be related by hidden dualities, i.e., seemingly
different field theories may actually be identical in the infrared limit. Among
all the proposed dualities, one has attracted particular interest in the field
of strongly-correlated quantum-matter systems: the one relating the easy-plane
noncompact CP model (NCCP) and noncompact quantum electrodynamics (QED)
with two flavors () of massless two-component Dirac fermions. The
easy-plane NCCP model is the field theory of the putative deconfined
quantum-critical point separating a planar (XY) antiferromagnet and a dimerized
(valence-bond solid) ground state, while noncompact QED is the theory for
the transition between a bosonic symmetry-protected topological phase and a
trivial Mott insulator. In this work we present strong numerical support for
the proposed duality. We realize the noncompact QED at a critical point
of an interacting fermion model on the bilayer honeycomb lattice and study it
using determinant quantum Monte Carlo (QMC) simulations. Using stochastic
series expansion QMC, we study a planar version of the - spin
Hamiltonian (a quantum XY-model with additional multi-spin couplings) and show
that it hosts a continuous transition between the XY magnet and the
valence-bond solid. The duality between the two systems, following from a
mapping of their phase diagrams extending from their respective critical
points, is supported by the good agreement between the critical exponents
according to the proposed duality relationships.Comment: 14 pages, 9 figure
1,3-Dihydroxy-2-(hydroxymethyl)propan-2-aminium formate
The title compound, C4H12NO3
+·CHO2
−, was obtained from 1,3-dihydroxy-2-(hydroxymethyl)propan-2-aminium acetate and ethyl formate. In the crystal, the cations and anions are held together by intermolecular N—H⋯O and O—H⋯O hydrogen bonds
The impact of an abandoned mercury mine on the environment in the Xiushan region, Chongqing, southwestern China
Mercury contamination is a serious problem in the Hg mining area of Xiushan County, Chongqing, southwestern China. The concentrations of total mercury (THg) and methylmercury (MeHg) in paddy soil, surface water, and rice (grain) samples were determined to investigate the regional distribution of Hg contamination. Simultaneously, gaseous elemental Hg (GEM) in ambient air near the sampling sites was measured. The total Hg concentrations in surface water were highly elevated, ranging from 13 to 2390 ng/L, and the total MeHg concentrations varied between 0.17 and 1.1 ng/L. The dissolved Hg and MeHg concentrations in surface water ranged from 4.7 to 470 ng/L and 0.14–0.35 ng/L, respectively. High THg and MeHg concentrations were also obtained in paddy soils from mining areas, ranging from 0.45 to 68 μg/g and 0.13–4.8 ng/g, respectively. Similar to the high concentrations in water and soil, the THg concentration in rice (grain) ranged from 4.7 to 550 ng/g and MeHg from 2.9 to 26 ng/g. Elevated Hg concentrations in rice, as a staple food of local residents, confirmed that rice consumption could be a vital pathway for MeHg exposure to native people. Humic acid and fulvic acid had significant correlations with soil MeHg, implying that they have important roles that influence MeHg production in soil. The spatial distribution characteristics of Hg and MeHg pollution in the local environment indicated their origins from historic Hg mining sites in the Xiushan area.acceptedVersio
Observation of tunable topological polaritons in a cavity waveguide
Topological polaritons characterized by light-matter interactions have become
a pivotal platform in exploring new topological phases of matter. Recent
theoretical advances unveiled a novel mechanism for tuning topological phases
of polaritons by modifying the surrounding photonic environment (light-matter
interactions) without altering the lattice structure. Here, by embedding a
dimerized chain of microwave helical resonators (electric dipole emitters) in a
metallic cavity waveguide, we report the pioneering observation of tunable
topological phases of polaritons by varying the cavity width which governs the
surrounding photonic environment and the strength of light-matter interactions.
Moreover, we experimentally identified a new type of topological phase
transition which includes three non-coincident critical points in the parameter
space: the closure of the polaritonic bandgap, the transition of the Zak phase,
and the hybridization of the topological edge states with the bulk states.
These results reveal some remarkable and uncharted properties of topological
matter when strongly coupled to light and provide an innovative design
principle for tunable topological photonic devices.Comment: 6 pages, 4 figure
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