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Background: Patients with Crohn’s disease (CD) undergoing bowel resection often suffer from depression and acute pain, which severely impairs their recovery. We aimed to investigate the effects of S-ketamine preconditioning on postoperative depression in patients with CD undergoing a bowel resection with mild to moderate depression and to observe whether it can relieve postoperative pain and anti-inflammation. Methods: A total of 124 adult patients were randomized into one of the two groups. Patients in the S-ketamine group received a 0.25 mg/kg S-ketamine intravenous drip under general anesthesia induction, followed by a continuous infusion of S-ketamine with 0.12 mg/kg/h for more than 30 min through target-controlled infusion. Patients in the placebo group received 0.9% saline at an identical volume and rate. The primary outcome measure was the 17-item Hamilton depression Scale (HAMD-17). The secondary outcomes were scores on the following questionnaires: a nine-item patient health questionnaire (PHQ-9); a quality of recovery (QoR-15) form; and a numeric rating scale (NRS). Additional secondary outcomes included the levels of C-reactive protein (CRP) and interleukin 6 (IL-6) on postoperative days (PODs) 1, 3, and 5, the length of hospital stay, and opioid use throughout the hospital stay. Results: The scores of PHQ-9 and HAMD-17 in the S-ketamine group were lower than those in the placebo group on postoperative days (PODs) 1, 2, and 7 (p < 0.05). The scores of QoR-15 in the S-ketamine group were higher than those in the placebo group on postoperative days (PODs) 3 and 5 (p < 0.05). The NRS scores of PACU, postoperative days 1 and 2 in the S-ketamine group were lower than those in the placebo group (p < 0.05). There was no significant difference in the CRP and IL-6 levels on postoperative days (PODs) 1, 3, and 5, postoperative complications, and hospital stay between the two groups (p > 0.05). Conclusions: The trial indicated that the intraoperative administration of low-dose S-ketamine could alleviate mild-to-moderate depressive symptoms and postoperative pain in patients with Crohn’s disease undergoing bowel resection without worsening their safety.

We report on an identification of a new gamma-ray emitting narrow-line Seyfert 1 galaxy (gamma-NLS1), SDSS J095909.51+460014.3 (z = 0.399), by establishing an association with a gamma-ray source 4FGL 0959.6+4606, although its low-energy counterpart was suggested to be a radio galaxy 2MASX J09591976+4603515. WISE long-term light curves of these two sources reveal diverse infrared variability patterns. Brightenings of 2.5 mag are detected for the former source, while flux decays of 0.5 mag are found for the other one. More importantly, the time that the infrared flux of the NLS1 rises, is coincident with the time of flux increase of 4FGL 0959.6+4606. At the same time, no infrared activity of the radio galaxy has been observed. A specific analysis of 15-month Fermi-LAT data, aiming at the high gamma-ray flux state, yields a significant source (TS =43). The corresponding gamma-ray localization analysis suggests that only the NLS1 falls into the uncertainty area, further supporting the updated association relationship. A broadband spectral energy distribution of SDSS J095909.51+460014.3 has been drawn and well described by the classic single-zone homogeneous leptonic jet model. Its jet properties are investigated and found to be comparable with the known gamma-NLS1s., 8 pages, 7 figures,2 tables, A&A in press

When two-dimensional atomic crystals are brought into close proximity to form a van der Waals heterostructure, neighbouring crystals can start influencing each others electronic properties. Of particular interest is the situation when the periodicity of the two crystals closely match and a moir�� pattern forms, which results in specific electron scattering, reconstruction of electronic and excitonic spectra, crystal reconstruction, and many other effects. Thus, formation of moir�� patterns is a viable tool of controlling the electronic properties of 2D materials. At the same time, the difference in the interatomic distances for the two crystals combined, determines the range in which the electronic spectrum is reconstructed, and thus is a barrier to the low energy regime. Here we present a way which allows spectrum reconstruction at all energies. By using graphene which is aligned simultaneously to two hexagonal boron nitride layers, one can make electrons scatter in the differential moir�� pattern, which can have arbitrarily small wavevector and, thus results in spectrum reconstruction at arbitrarily low energies. We demonstrate that the strength of such a potential relies crucially on the atomic reconstruction of graphene within the differential moir�� super-cell. Such structures offer further opportunity in tuning the electronic spectra of two-dimensional materials., 35 pages, 15 figures

We report on OVRO, WISE, Swift and Fermi-LAT observations of the high redshift blazar CGRaBS J0733+0456, from which significant flux variations in radio, infrared (IR) as well as $��$-ray domains are detected. Particularly, the amplitude of long-term IR variation is over one order of magnitude and the IR variability timescale can be constrained as short as a few hours in the source frame. The IR and $��$-ray light curves are found to be rather similar, and the strong quasi-simultaneous infrared and $��$-ray flares are proved to be unique among the nearby $��$-ray sources. This is the first time to identify a $��-$ray blazar at redshift $z\geq 3$ with multi-wavelength flux variations (flares). Broadband spectral energy distributions in different flux states are constructed and theoretically described. The $��-$ray flares from some blazars as distant as redshift $\sim$ 5 are expected to be detectable for Fermi-LAT., 13 pages, 4 figures and 1 table, ApJL in press

In this paper, two types of underwater discharges, spark discharge and corona discharge, are investigated by optical diagnosis using a high speed framing camera (HSFC) with the framing time within nanoseconds under the same experimental conditions. In order to capture the photographs of streamer propagation, the influence of the randomicity of the pre-breakdown duration is taken into consideration. By increasing the conductivity of water, the randomicity reduces effectively. Experimental results show that, for a spark discharge, the process can be separated into three stages: the generation and propagation of a streamer, the generation and expansion of the discharge channel, and the development and annihilation of the plasma. The streamers do not directly move to the opposite electrode, but form a bush-like figure. With the increase of the number of branches, the velocity of streamer propagation slows down. The trajectory of the initial channel between electrodes is not straight. However, with the channel expanding, its shape transforms into a straight column. For a corona discharge, there are two stages: the generation and propagation of a streamer, and the stagnation and annihilation of the streamer. The initial streamer in a corona discharge is generated later than in a spark discharge. The forms of streamers for both kinds of discharge are similar; however, streamers generated by a corona discharge propagate with a slower velocity and the number of branches is less compared with a spark discharge. When the energy injection stops, the luminescence of plasma inside the discharge channel (spark discharge) or streamers (corona discharge) becomes weaker and weaker, and finally disappears.

We investigated eleven exchange-correlation energy density functionals including generalized gradient approximation (GGA) (PBE, PW91), meta-GGA (M06-L), hyper-GGA (M06-2X, B3LYP, X3LYP), LC-DFT methods (CAM-B3LYP, LC-ωPBE, ωB97X), and density functional theory with dispersion corrections (DFT-D) methods (ωB97X-D, B97-D) for their performance in describing systems with conventional and non-conventional hydrogen bonds. After comparing the results using the benchmark CCSD(T)/aug-cc-pVQZ approach we found that the M06-2X and ωB97X-D functionals provided the most accurate and reliable results for the fifteen systems studied in this work with strong, moderate, and weak hydrogen bonds. It is important to employ an appropriate basis set to predict the binding energy of hydrogen bonds for all DFT methods and we found that the basis set of 6-311++G(2d, 2p) or aug-cc-pVDZ is adequate. The effect of the basis set superposition error (BSSE) is relatively small for the DFT methods tested. All the methods except for ωB97X and ωB97X-D were found to produce equally accurate or even more accurate results without BSSE correction.

By modeling direct transient heat conduction problems via finite element method (FEM) and precise integral algorithm, a new approach is presented to solve transient inverse heat conduction problems with multi-variables. Firstly, the spatial space and temporal domain are discretized by FEM and precise integral algorithm respectively. Then, the high accuracy semi-analytical solution of direct problem can be got. Finally, based on the solution, the computing model of inverse problem and expression of sensitivity analysis are established. Single variable and variables combined identifications including thermal parameters, boundary conditions and source-related termsetc. are given to validate the approach proposed in 1-D and 2-D cases. The effects of noise data and initial guess on the results are investigated. The numerical examples show the effectiveness of this approach.

In this paper several methods including MNDO, multiple scatteringX α and ab initio self-consistent-field MO theories have been used to calculate the minimum energy geometries, force constants, vibrational frequencies, and11B quadruple coupling constants of B-O polyhedra such as [BO3], [BO4], [OB2] and [OB3]. The results are in good agreement with the experimental and calculated values so far published by other authors.

Small hydro (SH) / photovoltaic (PV) hybrid power system (HPS) is a clean and economic way of renewable energy power generation, which has a good complementary according to local resources distribution features. Operation characteristics of SH and PV generation system are analyzed in detail and a novel control strategy is proposed in this paper. The PV generation system is designed to have the same operation properties as the SH generation system. The simulation results verify the performance of the proposed method.

We demonstrate a kW continuous-wave ytterbium-doped all-fiber laser oscillator with all domestic fiber components: a 7 × 1 fused fiber bundle combiner, a fiber Bragg grating and a double-clad gain fiber. The oscillator operates at 1079.48 nm with 80.94% slope efficiency and shows no limit of temperature and nonlinear effects. These indicate that the passive fiber components and the gain fiber are all qualified for the high power environment. No evidence of the signal power roll-over shows that this oscillator possesses the capacity to higher output with available pump power.

The direction of symmetry axis of parallel fracture set in fractured hydrocarbon reservoir affects the transmission of seismic waves markedly, so a medium named fracture-induced TTI (tilted transverse isotropy) double-porosity medium is studied here to discuss the effect of different dip and azimuth angles of a fracture system. Based on the theories of fracture-induced HTI (horizental transverse isotropy) double-porosity medium, the softness and dispersion matrixes of fracture-induced TTI double-porosity medium are derived with the application of Bond transform, and finally, single-order velocity-stress equations are obtained. Furthermore, numerical simulations in xoz plane of 2.5 dimensional vector wavefield are carried out by the method of high-order staggered-grid finite-difference under perfect matched layer (PML) boundary conditions. The results show that the dipand azimuth angles of fractures have great impacts on seismic wave propagation, since the angles can cause the phenomena of shear wave splitting and, in the two-layer model of fracture-induced TTI double-porosity, converted shear wave splitting and shear wave sub-splitting. All of these increase the complexity of seismic wavefield and will lay a foundation of further studies on seismic wave propagation in actual earth layers.

The effects of codopants and the deposition parameters such as gas flowrate and pressure in tube during the fabrication of fiber performs are studied. It is found that the fluorescence spectrum of Yb3+ can shift when codoping other elements, according to which, a double cladding Yb3+-doped fiber that is beneficial for 1018 nm laser is fabricated for the first time. When the fiber length is 7 m, an output of 22.8 W at 1018 nm is obtained. The optical-optical conversion efficiency is approximately 70%, and there are neither spontaneous radiation nor saturation.

We report an experimental study on a double-arched LD array stagger pumped electro-optic Q-switched Nd:YAG laser without water cooling by using a convex-concave compensate resonator. Perfect matching of the gain field inside the rod and the fundamental mode of the cavity is made by this structure. When the repetition rate is 20 Hz, A maximum output energy at 1064 nm wavelength of 176 mJ (M2 = 1.55) and 9.6 ns FWHM pulse width in fundamental mode Q-switch operation is obtained with LD injection current 120 A. The optical-optical conversion efficiency is 14.7%, the divergence angle of the output beam is about 1.8 mrad.

Convergent beam electron diffraction (CBED) patterns of twisted bilayer samples exhibit interference patterns in their CBED spots. Such interference patterns can be treated as off-axis holograms and the phase of the scattered waves, and hence the interlayer distance can be reconstructed. A detail protocol of the reconstruction procedure is provided. In addition, we derived an exact formula for reconstructing the interlayer distance from the recovered phase distribution, which takes into account different chemical composition of the individual monolayers. It is shown that one interference fringe in CBED spot is sufficient to reconstruct the distance between the layers, which can be practical for imaging samples with a relatively small twist angle or when probing small sample regions. The quality of the reconstructed interlayer distance is studied as a function of the twist angle. At smaller twist angles the reconstructed interlayer distance distribution is more precise and artifact-free. At larger twist angles, artifacts due to the moiré structure appear in the reconstruction. A method for reconstruction of average interlayer distance is presented. As for resolution, the interlayer distance can be reconstructed by the holographic approach at accuracy of ±0.5 Å, which is a few hundreds times better than the intrinsic z-resolution of diffraction limited resolution as expressed through the spread of the measured k-values. Moreover, we show that the holographic CBED imaging can pick as small as 0.1 Å variations in the interlayer distance, though the quantitative reconstruction of such variations suffers from a large error.