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Objective To evaluate the clinical efficacy of positioning guide templates for maxillary wholly impacted supernumerary teeth to provide technological solutions for clinical applications. Methods After approval by the hospital ethics committee and informed consent given by the patients. Data from 136 patients with maxillary wholly impacted supernumerary teeth from January 2016 to April 2022 were analyzed retrospectively. The patients were divided into two groups according to the usage of the positioning guide template. The experimental group included patients using the positioning guide template (71 cases), and the control group did not use the positioning guide template (65 cases). The operation time and complications were statistically analyzed to evaluate the clinical efficacy after surgery. Results All operations were successfully completed. The average operation time in the experimental group was (21.5 ± 3.4) min, significantly shorter than that in the control group (27.2 ± 4.9) min. There were statistically significant differences between the experimental and control groups (t = 7.599, P

We propose to realize bipartite and tripartite entanglements transfer in a cavity magnomechanical system consisting of a microwave cavity with an yttrium iron garnet (YIG) sphere and a silicon-nitride membrane in it. The initial magnon–YIG phonon entanglement and photon-membrane phonon entanglement caused by the magnetostrictive interaction and the optomechanical interaction can be effectively transferred to magnon–membrane phonon entanglement and photon–YIG phonon entanglement. Photon–magnon–YIG phonon and photon–magnon–membrane phonon entanglements can also be realized in the system. These two types of tripartite entanglements can be easily transferred from one type to the other by adjusting the detuning or dissipation ratio. Moreover, the bipartite and tripartite entanglements and their transfer are all robust against temperature. Furthermore, by introducing supermodes formed by the photon and magnon modes, we find that the entanglement between the two mechanical modes can be obtained under the condition of an extremely low temperature. And the effective detuning region of the YIG phonon-membrane phonon entanglement is complementary to the detuning regions of other bipartite entanglements. Our results indicate that the combination of cavity magnomechanical and optomechanical systems could provide more flexible controllability of bipartite and tripartite entanglements and their transfer and could serve as a potential quantum interface among microwave, magnon, and mechanical systems.

Abstract Objective This study aimed to explore the relationship between the sarcopenia index (SI) and the risk of pneumonia in hospitalized patients with acute alcohol withdrawal syndrome (AWS). Study design We have performed a retrospective study of individuals with AWS from a teaching hospital in western China. Patients' data were retrieved from the medicinal record databases. Patients' primary (upon admission) blood serum creatinine (Cr) and cystatin C (CysC) levels were incorporated into the records. Participants were separated into low and high SI cohorts based on the three-quarter digit of SI (SI = serum Cr/serum CysC ratio × 100). The association between SI and the risk of pneumonia in hospitalized patients with AWS was assessed by logistic regression analysis. Result Three hundred and twelve patients with acute AWS were included in this retrospective analysis. Among hospitalized patients with acute AWS, the incidence of pneumonia was 13.78%. The average median age of acute AWS patients with pneumonia was 55.28 (10.65) years, and the mean age of acute AWS individuals without pneumonia was 51.23 (10.08) years. In the univariate analysis, the high SI group (SI > 87.91) had a lower incidence of pneumonia than the low SI group (SI ≤ 87.91) (high SI vs. low SI, 6.41% vs. 16.24%, p = 0.029). Further logistic regression analysis showed that the high SI group demonstrated a poorer risk of pneumonia (OR = 0.353, 95%CI: 0.134–0.932, p = 0.036). After adjusting for possible confounders, the risk of pneumonia remained low in the high SI group (OR = 0.358, 95%CI: 0.132–0.968, p = 0.043). Conclusion Our results showed that SI was linked with the risk of pneumonia in hospitalized individuals with acute AWS. We further suggest that it could be a pneumonia risk factor, especially in medical centers where sarcopenia diagnosis is unavailable.

In the distribution network,the participation of flexible resources such as distributed new energy and controllable load in demand response has become an important measure of load adjusting in the new power system. How to consider the uncertainty of user responsiveness and balance the interests of multiple participants is very critical. In this paper,the fuzzy control model of user responsiveness is established firstly,and the benefit function model of multi-agent demand response participants such as power supplier,load aggregator and user is given considering the fuzziness of user responsiveness. Furthermore,with the objectives of minimizing the deviation of daily load curve and minimizing the system cost,the upper optimization adopts the optimal demand response scheme of the power supplier. The lower optimization obtains the best task allocation between the power supplier and the load aggregator,so as to establish the two-layer model of multi-agent collaborative demand response of the power supplier,the load aggregator and the user. A solution method based on Stackelberg game theory and k-means clustering algorithm is proposed. Finally,the simulation results of historical data in an area show that the model can effectively screen high-quality demand response resources to suppress load fluctuation under the consideration of user responsiveness and collaborative of multi-agent interests.

A multifunctional outburst simulation test system was independently developed to monitor the temperature of the coal seam and roadway throughout the entire outburst process. Outburst simulation experiments under different gas pressures were carried out. The results show that: ① the coal seam gas pressure quickly drops to atmospheric pressure after outburst, however, the temperature evolution of coal seam has a certain lag, which is mainly controlled by the desorption of adsorbed gas and the expansion of free gas; three stages can be seen in the coal seam temperature evolution characteristics: quick decline, rapid increase, and slow change; peak values of coal seam temperature decline are 0.56, 0.23, and 0.11 ℃, respectively, and average decline rates are 0.042, 0.015, and 0.008 ℃/s when the adsorption gas pressure is 2.0, 0.85, and 0.35 MPa; the higher the gas pressure is, the greater the coal seam temperature decline and the faster the decline rate is, which is positively correlated; ② the change of the roadway temperature is simultaneously influenced by various factors such as desorption of gas from the outburst coal, expansion and pressure relief of ejected gas, shock wave disturbance and heat exchange with the environment, showing an evolutionary trend of a brief increase followed by an immediate and significant decrease and finally rise to the ambient temperature; in the three tests, the peak values of roadway temperature drop are 3.19, 2.41 and 1.09 °C, and the average decline rates are 0.249, 0.188 and 0.094 °C/s, respectively; ③ the coal seam and roadway temperatures have overall similarity in time evolution and significant difference in the magnitude of change; the further fragmentation of the outburst coal body in the roadway and the large amount of desorption of gas are the main controlling factors for the evolution of the roadway temperature and the main reason for the large amount of decrease in the roadway temperature.

In response to the urgent need for the development of low-orbit 5th Generation Mobile Networks (5G) protocol standards, R16 protocol standards and terminal baseband chips based on 5G low-orbit broadband satellite communication systems, a Primary Synchronization Signal (PSS) detection algorithm of " two blocks combined and divided into two cross-correlation" is proposed for coarse frequency offset estimation based on the analysis of the Low Earth Orbit (LEO)-5G system's PBCH link structure and downlink time-frequency synchronization overall architecture. The frequency offset is further estimated through Secondary Synchronization Signal (SSS) correlation, and combined with Cell-Specific Reference Signal (CRS) pilot signal to determine the precise synchronization LEO-5G downlink synchronization algorithm with Field Programmable Gate Array (FPGA). The feasibility and effectiveness of the algorithm were verified by simulation using Vivado and Matlab. The results show that the synchronization algorithm has good real-time performance and high stability. The accuracy rate of the downstream time-frequency synchronization FPGA module with Management Information Base (MIB) parsing is about 83.07%. The chip storage resource consumption for the evaluation of timing and resource consumption is only 11.7%. All indicators meet the indicator requirements.

CeO2-8YSZ (CYSZ) composite agglomerated powder was synthesized by spray drying of 20% micron-scale CeO2 powder doped with nano-ZrO2-8 mol% Y2O3 (8YSZ) powder. The effect of the binder (carboxymethyl cellulose, CMC) ratio on the properties of the composite agglomerated powder was investigated with the aid of a laser particle size tester, scanning electron microscopy (SEM) and incidental energy spectrometry (EDS). A CYSZ thermal barrier coating with a columnar structure was prepared by PS-PVD, and EDS analysis of the coating cross-section and surface was carried out. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze the physical phases of the coating. The results show that agglomerated powder with high sphericity, good flowability and uniform particle size distribution can be obtained with a binder ratio of 2%, the prepared coating has a uniform distribution of Ce element, and the coating phase is basically a t-phase structure, in which Ce4+ replaces Zr4+ and enters into the ZrO2 lattice to form a homogeneous solid solution structure, showing the inhibition of the transition from t-phase to m-phase by CeO2 doping. In addition, the prepared CYSZ coating remained intact after 100 cycles of water cooling at 1100 °C, showing high thermal shock resistance.

The SHARK program (Simulation-based High-fidelity Advanced Reactor physics Kit) is a high-fidelity heterogeneous neutronics code for the numerical reactor system being developed at the Nuclear Power Institute of China (NPIC). The program uses a Constructive Solid Geometry (CSG) framework to model various complex geometries. To enhance the flexibility and robustness during continuous development process, SHARK program attempts to support a rich set of methods, tools and library options within a unified general framework as a “toolkit”. For the multi-core clustered supercomputer architectures that are commonly used today, the SHARK program adopts a hybrid parallel strategy of MPI and OpenMP to achieve complementary advantages between them. In addition, the framework of SHARK program is designed with a true object-oriented manner. Through reasonable abstraction, inheritance and encapsulation, the maintainability and extensibility of the code are improved, and long-term team development is facilitated. Up to now, key modules for cross-section generation, heterogeneous transport calculation and microscopic depletion have been developed under the general frameworks. The main features of SHARK’s “resonance-transport-depletion” coupling system are elaborated in this paper, and some verification and validation (V&V) results in the current phase are presented and discussed.

Objective: To solve the problems of low whole rate of the tobacco shredded from the cabinet, high rate of broken shreds and high concentration of regional dust. Methods: A flexible feeding and discharging system of the wire storage cabinet was designed, which effectively reduced the shredded tobacco and the regional dust concentration through the automatic telescopic sliding plate and the sliding and lifting raking roller. Results: After adopting the flexible feeding and discharging system of the wire storage cabinet, the change rate of the whole wire rate increased by 1.1%, from 80.2% to 81.1%, and the broken wire rate decreased to 2.2%; The regional dust concentration C-TWA decreased to 0.5 mg/m3. Conclusion: The improved wire storage cabinet achieves the purpose of cleaner production, cost reduction and efficiency enhancement.

Container technology promotes the rapid development of cloud computing with its flexible and efficient features, but it also introduces security threats such as co-resident attacks, escape attacks, and common mode attacks. In response to these security threats, a dynamic heterogeneous scheduling method based on Stackelberg game in the container cloud was proposed. First, a heterogeneous mirrored resource pool is constructed to suppress the spread of attacks based on common-mode vulnerabilities on the cloud. Then, the offensive and defense interaction process is modeled as a Stackelberg game model. Finally, the offensive and defensive model is analyzed, and the system scheduling problem is modeled as a mixed integer non-linear programming problem to solve the system's optimal scheduling strategy. Experiments show that the proposed method can improve the defense effect of the cloud platform and reduce the system defense overhead.

Fast charge transfer and lithium-ion transport in the electrodes are necessary for high performance Li–S batteries. Herein, a N-doped carbon-coated intercalated-bentonite (Bent@C) with interlamellar ion path and 3D conductive network architecture is designed to improve the performance of Li–S batteries by expediting ion/electron transport in the cathode. The interlamellar ion pathways are constructed through inorganic/organic intercalation of bentonite. The 3D conductive networks consist of N-doped carbon, both in the interlayer and on the surface of the modified bentonite. Benefiting from the unique structure of the Bent@C, the S/Bent@C cathode exhibits a high initial capacity of 1,361 mA h g−1 at 0.2C and achieves a high reversible capacity of 618.1 m Ah g−1 at 2C after 500 cycles with a sulfur loading of 2 mg cm−2. Moreover, with a higher sulfur loading of 3.0 mg cm−2, the cathode still delivers a reversible capacity of 560.2 mA h g−1 at 0.1C after 100 cycles.

The behavior of the room temperature tensile of the FGH96 P/M superalloys connected by the inertia friction welding before and after the aging treatment was investigated, and the failure mechanism of the FGH96 P/M superalloys was evaluated. The results show that, for the FGH96 P/M superalloy samples in the as-welded (original) state, the strength of the superalloy samples in the welding line zone (WLZ) and the heat affected zone (HAZ) is lower than that of the parent alloys, and the plastic strain is the largest during the room temperature tensile process, due to the weak comprehensive strengthening effect of γ′ phase and the straight grain boundaries in WLZ and HAZ. Because of the large grain size in HAZ, the weak strengthening effect of grain boundaries, and the lower dislocation density than that of WLZ, the strength of the superalloy samples in HAZ becomes the weakest, where the cracks originate and show a certain plastic characteristic of the fracture. For the FGH96 P/M superalloy samples after the aging treatment, the comprehensive strengthening effect of γ′ phase is improved, due to the coarsening of γ′ phase, the increase of the strengthened phase volume fraction, and the mismatch increase between γ and γ′, compared with the superalloy samples in the as-welded state, the strength of the superalloy samples after the aging treatment in WLZ and HAZ is higher than that of the parent alloys, and the plastic strain of the parent alloys is larger during the room temperature tensile process. The M23C6 carbide precipitated continuously or semi-continuously weakens the bonding strength of grain boundary in the as-welded state, leading to the sample fracture and showing the characteristic of brittle fracture. The results of microhardness test verify the strength distribution of the FGH96 P/M superalloy samples in the as-welded state and after the aging treatment.

ObjectiveThis study systematically reviews the clinical efficacy and safety of twist-drill craniostomy with hollow screws in chronic subdural hematoma treatment.MethodsA computerized search of PubMed, Embase, Web of Science, Cochrane Library, World Health Organization International Trial Registry platform, CBM, CNKI, and Wanfang Database was performed to retrieve randomized controlled trials or case-control trials using twist-drill craniostomy (TDC) with hollow screws for the evacuation of chronic subdural hematoma from the date of databases' inception to July 2021. Two investigators independently screened the studies and extracted data in strict accordance with pre-established inclusion and exclusion criteria. RevMan 5.3 software or STATA was used for meta-analysis after evaluating the methodological quality of the included studies.ResultsA total of 4 randomized controlled trials and 16 case-control trials with a total of 2,536 cases were included. Results of the meta-analysis showed that the surgical success rate and postoperative recurrence rate of TDC with hollow screws were slightly higher compared to the burr hole craniostomy (BHC) group, but showed no statistical significance (RR = 1.03, P = 0.05; RR = 1.13, P = 0.50). However, subgroup analysis showed that the use of YL-1 needle had a higher success rate and lower recurrence rate (RR = 1.05, P = 0.02 < 0.05; RR = 0.584, P = 0.002), and TDC with hollow screws had a lower incidence rate of postoperative complications and postoperative acute intracranial hemorrhage compared with BHC, also revealing an overall shorter hospital stay (RR = 0.57, P = 0.0002 < 0.05; RR = 0.584, P = 0.027 < 0.05; WMD = −3.752, P < 0.001). However, the postoperative mortality rate was practically the same between the two groups (OR = 1.01, P = 0.95 > 0.05).ConclusionTwist-drill craniostomy with hollow screws is not inferior or superior to BHC in efficacy, and this strategy is safer and minimally invasive, which is reflected in a lower incidence of acute intracranial hemorrhage, overall complication rate, and length of hospital stay.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/, identifier: CRD42021270835.

Coalbed methane development primarily relies on hydraulic fracturing and drainage gas extraction processes. The intrusion of external fluids and long-term drainage and extraction contribute to the water blocking effect, which becomes one of the crucial factors affecting production capacity. In this study, the coal reservoir of a certain coalbed methane in Hancheng, Shaanxi Province, was selected as the research object. The experimental method was employed to comprehensively evaluate the correlation between factors such as coal sample moisture content, permeability, porosity, properties of external liquids, and water blocking damage. The results indicated that there was a positive correlation between coal sample moisture content, liquid surface tension, and water blocking damage. On the other hand, coal sample pore permeability characteristics, liquid contact angle with rock samples, and water blocking damage showed a negative correlation. Building upon the aforementioned research, an investigation into remedial measures for water blocking damage was conducted. Additionally, a chemical treatment study using the compound surfactant system JSS-1 as a water-blocking agent was performed to manage the water blocking effect. The results demonstrated that JSS-1 as a water-blocking agent significantly reduced the surface tension of the wellbore fluid and improved its wetting behavior on the coal-rock surface. The laboratory experiments confirmed the capability of JSS-1 in managing the water blocking effect.

During postulated severe accident, large amount of hydrogen-vapor mixture will be released into the containment and inflammable gas mixture may form. Once the gas will be ignited, the generated pressure loads can jeopardize the integrity of the internal structures. As the local accumulation of high content hydrogen related much to the stratification and erosion mechanism, it is therefore of interest whether a stratification of gas layers will form within small containment. In this study, a stratification/erosion experiment is performed and the criteria under which the steady stratification will be destroyed by steam jet discussed. Then the simulation method is validated by the experimental data. At last, several severe accident scenarios for Chinese SMR performed and one of them is adopted for containment hydrogen CFD analysis. It is shown that high content of hydrogen will form in the upper part of the containment, and clear gas stratification will form, such stratification will be enhanced due to the condensation effect of steel containment wall.

The effect of surface roughness based on PS-PVD process on the structure of YSZ ceramic coating was studied. The influence mechanism of surface roughness on gas-phase deposition and structure formation of ceramic coating was discussed. YSZ ceramic coating was prepared by PS-PVD process on K417G superalloy prefabricated with NiCoCrAlYTa bond coating. The morphology and structural characteristics of PS-PVD YSZ coating were analyzed by means of SEM, roughness detector and 3D surface topography instrument. Substrate surface roughness has a great influence on PS-PVD coating structure. When the surface roughness of the substrate is Ra ≤ 2μm, 2μm < Ra < 6μm, and Ra ≥ 6μm, respectively, the coating roughness is in the range of 3.5-5, 6-10μm and 10-15μm, respectively. The diameter of cauliflower head increases with the increase of the surface roughness of substrate. The dP=38.5μm, d280S=25.5μm, d60S=38.7μm, d24S=102μm and dS=137μm. In the process of PS-PVD gas-phase deposition, surface roughness mainly affects the growth and formation of coating differential structures through shadow effect. With the increase of substrate surface roughness, YSZ ceramic coating is affected by shadow effect and the size of cauliflower head and the gap width between columnar structures are increased, forming a relatively loose structure.

The study was aimed at exploring the effects of applying ordinary and nano zeolite on the soil pH, soil available cadmium (Cd) content, soil Cd speciation and Cd uptakes by tobacco using pot experiment with simulated Cd contaminated soil indoors. The results showed that soil pH increased and available Cd content reduced with the amount of ordinary and nano zeolite increasing. Compared with the control, the application of ordinary and nano zeolite increased soil pH at 0.47 - 1.05 and 0.73 - 1.57, respectively, and reduced the available Cd contents at 19.3% - 32.7% and 23.2% - 40.5%, respectively. In addition, soil pH had significantly negative correlation with available Cd content in each treatment (p

For an atomic system with cascade four-level type, a useful scheme about three-dimensional (3D) atom localization is proposed. In our scheme the atomic system is coherently controlled by using a radio-frequency field to couple with two-folded levels under the condition of the existence of probe absorption. Our results show that detecting precision of 3D atom localization may be obviously improved by properly adjusting the frequency detuning and strength of the radio-frequency driving field. So our scheme could be helpful to realize 3D atom localization with high-efficiency and high-precision . In the field of laser cooling or the atom nano-lithography, our studies provide potential applications.

In the past decades, much attention has been paid to toxicity assessment of nanoparticles prior to clinical and biological applications. While in vitro studies have been increasing constantly, in vivo studies of nanoparticles have not established a unified system until now. Predictive models and validated standard methods are imperative. This review summarizes the current progress in approaches assessing nanotoxicity in main systems, including the hepatic and renal, gastrointestinal, pulmonary, cardiovascular, nervous, and immune systems. Histopathological studies and specific functional examinations in each system are elucidated. Related injury mechanisms are also discussed.