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Abstract The norovirus (NoV) genome is diverse. Therefore, this study explored the epidemiological characteristics and genetic features of NoV in Ningxia Hui Autonomous Region, China, from 2011 to 2022 to clarify the genetic diversity in this region. Stool samples were screened for NoV and then sequenced and genotyped. In total, 1,788 of 13,083 specimens were NoV -positive (13.67%); 204 (1.56%) and 1,584 (12.11%) cases were GI and GII, respectively. Additionally, 559 were NoV infection with other viruses (4.27%), primarily with rotavirus (277/559, 49.55%). The NoV incidence rate was the highest among children aged 0–2 years (18.09%, 1054/5,828) and lowest among adults aged 45–64 years (110/1,495, 7.36%); it was also higher in the winter and spring than in the other seasons. GI.3[P3] was the dominant GI genotype. The dominant GII genotype changed roughly every two years. In the GII group, GII.4 was the most common genotype (46.79%), followed by GII.3 (21.34%), GII.2 (12.34%), and GII.17 (9.77%). There were three variants of GII.4 Den Haag, GII.4 New Orleans and GII.4 Sydney identified in the detected GII.4 strains, with GII.4 Sydney dominating. The GII.4 (87.36%), GII.3 (86.35%), and GII.2 (72.92%) strains were primarily detected in children, whereas it was the GII.17 (52.63%) strain in adults. Overall, the NoV genotypes in the Ningxia Hui Autonomous Region were diverse. Primarily, GII groups were dominant, but this changed over time.

Among the existing insulator defect detection methods, the automatic detection of inspection robots based on the instance segmentation algorithm is relatively more efficient, but the problem of the limited accuracy of the segmentation algorithm is still a bottleneck for increasing inspection efficiency. Therefore, we propose a single-stage insulator instance defect segmentation method based on both an attention mechanism and improved feature fusion network. YOLACT is selected as the basic instance segmentation model. Firstly, to improve the segmentation speed, MobileNetV2 embedded with an scSE attention mechanism is introduced as the backbone network. Secondly, a new feature map that combines semantic and positional information is obtained by improving the FPN module and fusing the feature maps of each layer, during which, an attention mechanism is introduced to further improve the quality of the feature map. Thirdly, in view of the problems that affect the insulator segmentation, a Restrained-IoU (RIoU) bounding box loss function which covers the area deviation, center deviation, and shape deviation is designed for object detection. Finally, for the validity evaluation of the proposed method, experiments are performed on the insulator defect data set. It is shown in the results that the improved algorithm achieves a mask accuracy improvement of 5.82% and a detection speed of 37.4 FPS, which better complete the instance segmentation of insulator defect images.

Purpose of Review: The effect of continuous positive airway pressure (CPAP) on resistant hypertension in patients at high risk with obstructive sleep apnea (OSA) needs further investigation. We aimed to determine the effect of CPAP on blood pressure in patients with resistant hypertension and OSA. Databases including PubMed, EMBASE, MEDLINE, the Cochrane Library, and CMB were searched. Data were pooled using a random-effects or fixed-effects model to derive weighted mean differences (WMDs) and 95% confidence intervals (CIs). Recent Findings: A total of 12 trials and 718 participants were included. Compared with control, CPAP significantly reduced 24-h systolic blood pressure (SBP) (WMD: − 5.92 mmHg [ − 8.72, − 3.11]; P＜0.001), 24-h diastolic blood pressure (DBP) (WMD: − 4.44 mmHg [− 6.26 , − 2.62]; P ＜0.001), daytime SBP (WMD: − 5.76 mmHg [ − 9.16, − 2.36]; P ＜0.001), daytime DBP (WMD: − 3.92 mmHg [− 5.55, − 2.30]; nighttime SBP (WMD: − 4.87 mmHg [ − 7.96 , − 1.78]; P = 0.002), and nighttime DBP (WMD: − 2.05 mmHg [− 2.99, − 1.11]; P＜0.001) in patients with resistant hypertension and OSA. CPAP improved the blood pressure both in the short (＜3 months) and long term (≥ 3 months). No significant impact on mean heart rate was noted (WMD: -2.76 beats per min [− 7.50, 1.97]; P = 0.25). Summary: CPAP treatment was associated with BP reduction in patients with resistant hypertension and OSA. [ABSTRACT FROM AUTHOR]

The rapid growth of grain yield in China accelerates a discussion on whether the grain system in China is sustainable. To answer the question, a comprehensive assessment from economic and environmental points is necessary. This study jointly used economic analysis (ECA), emergy evaluation (EME) and carbon footprint (CF) to analyze the environmental and economic sustainability of the grain production system in China based on the national statistical data during 2000–2015. Results showed that the costs of maize, wheat, rice and soybean had increased by 252–346% from 2000 to 2015, causing the lower profit of grain system in recent years. The situation resulted in a serious problem on economic sustainability of grain system in China. Meanwhile, the emergy sustainability index (ESI) of maize, wheat, rice and soybean systems were increasing during 2000–2015, and the CF on unit yield of the crops had been reduced by 10–30% in the study period. The results reflected the improved environmental sustainability of grain system in China during 2000–2015. Nevertheless, the emergy flow of industrial inputs for the crops were increased by 4–22% in the study period, and the CF from the inputs presented a growth rate of 16–23% as well during the same period. The results implied that the grain system in China was relying more on fossil-based inputs. Finally, according to the key points of cost, emergy and CF, we suggest that improving labor efficiency, advanced agricultural practices and optimizing cropping pattern will be effective ways to further improve the economic and environmental sustainability of grain system in China.

In solar observations, the vertical distribution of turbulence can be detected with a multidirectional Shack–Hartmann wavefront sensor, based on SLODAR or S-DIMM+. By expressing the measured cross-correlation as a linear combination of theoretical correlation functions for various height layers, the distribution of turbulence intensity can be obtained through fitting. The theoretical correlation functions in different heights are employed to describe the slope correlation and calculated based on the phase structure function corresponding to classical turbulence statistical theories such as Kolmogorov or von Karman. However, for turbulence that does not obey classical theory, this deviation of the statistical characteristics would result in the measurement accuracy degradation of seeing profiles. A method, so-called AutoCorrelation-SLODAR (AC-SLODAR), is proposed. The feasibility of transforming cross-correlation into autocorrelation is analysed theoretically. Then, the autocorrelation function is calculated based on the actual data to avoid the deviation introduced by the theoretical turbulence statistical model. Extracting statistical characteristics from data also simplifies measurements, without requiring the evaluation of whether the data conforms to a particular classical statistical model. AC-SLODAR was validated with simulation data generated by the open-source emulator SOAPY. The measured error was reduced by 10 per cent compared with SLODAR for the situation of turbulence model deviation. The performance of AC-SLODAR was further compared with those of SLODAR based on the actual data collected in 2016 and 2017 on the New Vacuum Solar Telescope. The corresponding results of AC-SLODAR are consistent with those of SLODAR using a pre-evaluated turbulent model. [ABSTRACT FROM AUTHOR]

Measuring the intensity and distribution of atmospheric optical turbulence at large-aperture astronomical telescope sites is crucial to optimizing turbulence correction for different layers. A real-time measurement of turbulence distribution in large-aperture telescopes would be valuable for the parameter optimization of adaptive optics (AO) systems, especially for large field-of-view AO systems such as multi-conjugate adaptive optics (MCAO) and ground-layer adaptive optics (GLAO). Based on the GLAO system of NVST at FSO, a real-time measurement system was deployed to assess the site's atmospheric turbulence intensity and distribution. This system is, to our knowledge, the first real-time turbulence parameter measurement system in the world with an AO system. We adopt pseudo-open loop methods to restore the turbulence information from the close-loop data of GLAO and measure the turbulence strength and distribution. Multiple subaperture pairs are used instead of a pair of subapertures for fitting calculation to increase the measurement accuracy. Two conventional measurement algorithms, SLODAR and S-DIMM+, are compared with the data from the open-source simulator SOAPY, to cross-verify the correctness of our calculation based on the data process of pseudo-open loop data and multiple subaperture pairs. The simulation results show that for two layers' turbulence input, approximately 93% of the turbulence is correctly detected with the SLODAR method and the given parameters of wavefront sensors and correctors, while the S-DIMM+ is 87%. Real-time measurements of atmospheric turbulence at the NVST site were carried out on 28 May 2023. The observation results indicated that approximately 80% of the turbulence was located below an altitude of 2000 m; only a few appear in the upper height. [ABSTRACT FROM AUTHOR]

We investigate the transport properties of a graphene nanoribbon with a tilted p-n junction. The conductance versus the Fermi energy shows step structures when the tilt angle is small. For the large tilt angles, the conductance oscillates rapidly with the tilt angle increasing, and the conductance decays non-monotonically with the longitudinal length of the p-n junction area. Based on the subband analysis, we explain these effects by the mix and the interference between different subbands of the ribbon. [ABSTRACT FROM AUTHOR]

Highlights • We formulize the terminal current in language of non-equilibrium Green's function for the systems with the Hamiltonian changed abruptly. • We find that the terminal current has a delay to the Hamiltonian change and estimate the amount of delay per bond. • We explain all our results by means of semiclassical picture. Abstract The current response for the parameter change of a mesoscopic system is a practical issue for future's circuit design. Nowadays most considered cases are various types of bias modulation, while the effect of change of conductor Hamiltonian is seldom addressed. In this paper, we investigate the response of ballistic transport induced by a sudden change of the conductor Hamiltonian. We formulize the terminal current in language of non-equilibrium Green's function. Our method is applied to one-dimensional tight-binding chains and we find that the terminal current has a delay to the Hamiltonian change. The amount of delay is not determined by the velocity of incident electrons in the bias window, but depends on the tight-binding hopping energy γ. The delay of current response at the detecting point away from where the Hamiltonian changes is C γ − 1 , where C is a constant independent of the system. [ABSTRACT FROM AUTHOR]

We investigate the transport properties of a four-terminal graphene device of which two terminals are beneath a pair of reversal top gate voltages. We find there exists quantum Hall-like effect without magnetic field applied. The curve of Hall conductance versus the Fermi energy shows steps, and the disorder can make the steps clearer. The average length of Hall conductance plateaus is of the order meV for the devices with the terminal widths of the order μm, which is within the scope of the experimental observation. The influences of gate voltage, device dimensions, and dispersion gap are also discussed. [ABSTRACT FROM AUTHOR]

Sublimation energy is the latent heat of phase transition from solid state directly to gas state, but it is difficult to measure experimentally. We propose a new method to determine the sublimation energy of materials by using the experimental data of blow-off impulse induced by electron beam and the computer program DRAM. With this new method, the sublimation energy of polyester is finally determined to be about 1.1 kJ/g. [ABSTRACT FROM AUTHOR]

Laser-directed energy deposition (LDED) is an effective method to fabricate structural gradient materials, which can be applied to the blisk (an integrated structure of blades and turbine disk) in the aero-engine. High-temperature mechanical properties are important to evaluate the performance of the blisk. However, the high-temperature performances of high-temperature titanium alloys such as TC25G alloy are difficult to meet the demands of the new generation of turbine materials. In this work, the mechanical properties at 550 °C of the TC25G/Ti 2 AlNb gradient material prepared by LDED were investigated. The results show that the gradient material can be divided into three parts: the TC25G alloy, the transition zone (TZ), and the Ti 2 AlNb alloy. The ultimate tensile strength of the gradient material at 550 °C was 846 MPa, which was improved compared to the as-forged TC25G substrate, and the elongation of the gradient material was 16.5 %. During the tensile test at 550 °C, the strain was mainly concentrated in the TC25G alloy part, in which the necking and final failure took place. [ABSTRACT FROM AUTHOR]