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Rotavirus (RV) vaccines have demonstrated substantial effectiveness in reducing the healthcare burden caused by gastroenteritis (RVGE) worldwide. This study aims to understand the differential impact of RV vaccination in reducing RVGE burden in children under 7 years old in China. A Markov Model was used to investigate the health impact of introducing two different RV vaccines into the Chinese population. The analysis was conducted for RV5, a live pentavalent human-bovine reassortant vaccine, and Lanzhou Lamb RV (LLR), a live-attenuated monovalent RV vaccine, separately, by comparing the strategy of each vaccine to no vaccination within a Chinese birth cohort, including 100,000 children modeled until 7 years of age. The vaccination scenario assumed a vaccination coverage of 2.5%, 2.5%, 90% and 5% for doses one, two, three and no vaccine, respectively, for both vaccines. Strategies with RV5, LLR, and no vaccination were associated with 9,895, 49,069, and 64,746 symptomatic RV infections, respectively. RV5 and LLR were associated with an 85% and 24% reduction in the total symptomatic RV infections, respectively, suggesting that the health benefits of RV5 are at least three-fold greater than those associated with the LLR. Further, strategies with RV5 and LLR resulted in an estimated 206 and 59-year increase in quality-adjusted life years (QALYs), respectively. Sensitivity and scenario analyses supported the robustness of the base-case findings. Use of RV vaccine is expected to improve RV-associated health outcomes and its adoption will help alleviate the burden of RVGE in China. RV5 use will result in significantly better health outcomes.

According to the characteristics of the actual service environment of inner cavity of automobile, the damp heat test, salt spray test and electrochemical AC impedance technology were used to evaluate the coating and establish the aging kinetic equation. Results showed that under the accelerated aging test, the coating was intact within 600 h of the damp heat test and 360 h of the salt spray test. The failure aging of the inner cavity coating in 3.5% (mass fraction) NaCl solution at 25 ℃ could be divided into three stages: the initial stage , the middle stage and the late stage of aging; the initial stage of aging (the 0th to 2nd cycle) had good corrosion resistance, and low frequency electrochemical impedance|Z| 0.01 Hz was on the order of 109 Ω·cm2 or more; in the middle stage (the 4th to 6th cycle), |Z|0.01 Hz was on the order of 105～108 Ω·cm2, the size and quantity of internal micropores increased, and the corrosion resistance was obviously attenuated; in the late stage (8th cycle), local bulges appeared on the surface, |Z|0.01 Hz was on the order of 105 Ω·cm2 and below, and the coating failed. Based on this, establishing the aging kinetic equation could predict and evaluate the service life and protective performance of the inner cavity anti-corrosive coatings.

Natural gas is a stable and flexible low-carbon fossil energy. It has comparative advantages on both supply and consumption sides. It can be used as a transitional energy for constructing a clean, low-carbon, safe, and efficient new energy system and for achieving carbon peak and carbon neutrality. Currently, China’s energy transition has many scheme designs. Huge differences exist in the development prospects of natural gas. In this study, we analyze the relationship, challenges, and principles of carbon peak and carbon neutrality. Based on these analyses, we study the opportunities for natural gas development in China, explore the comparative advantages of natural gas in key areas such as power generation, transportation, city gas, and industry, and summarize the constraints in terms of terminal prices, infrastructure, pricing mechanism, and development speed. We also propose the development goals and key tasks of China’s natural gas. Finally, five recommendations are proposed for China’s natural gas development under the carbon goals. The first is to strengthen top-level coordination and leadership to clarify the development positioning and ideas of natural gas.The second is to maximize the comparative advantages to promote natural gas consumption. The third is to rationally use domestic and foreign resources to ensure sufficient and reliable supply. The fourth is to promote infrastructure construction to improve the supply efficiency. The fifth is to strengthen the policies and mechanisms for land, finance, taxation.

Western China is an important area for increasing oil and gas reserves and production in China, and it is also the most arid and water-deficient area in the country; there is a complex linkage between energy and water resources in this region. Hence, it is important to promote the coordinated management of energy and water resources. In this article, we review the prospects and deployment of oil and gas production in Western China, investigate the development mode and water utilization status of different oil and gas fields from seven companies of China National Petroleum Corporation in Western China, and analyze the guarantee risks of water resource and water environment during gas and oil development. The research shows that oil and gas production has steadily increased in Western China in recent years, and the consumption of fresh water in oil and gas fields has changed little, owing to the continuous improvement in sewage treatment and recycling efficiency. However, considering the progressive development of unconventional oil and gas resources, future oil and gas development in Western China is likely to significantly affect the surface and underground water systems. It is suggested to develop precise water injection and waterless fracturing technology to stabilize oil production and control water use, increase the recycling of produced water to strengthen scientific water management, and improve the comprehensive allocation guarantee system of water resources, so as to reduce the impact of oil and gas development on water system while ensuring water use security for energy industry, thereby realizing the coordinated development of energy and water resources in Western China.

Objective To assess the value of real-time three-dimensional transoesophageal echocardiography (RT-3DTEE) in the diagnosis of pannus of prosthetic aortic valve. Methods A total of 89 patients with valve obstruction after receiving aortic valve replacement in our hospital were recruited between September, 2017 and September, 2019. All the patients underwent a second valve replacement, and the data of transthoracic echocardiography (TTE), transesophageal echocardiography (TEE) and RT-3DTEE of these patients were analyzed. Results Of the 89 patients with valve obstruction, 51 were diagnosed to have pannus with a mean thickness of 6.5±1.1 mm in the prosthetic aortic valve as confirmed by pathological examination of the surgical specimen. The thickness of the pannus measured by RT-3DTEE, TTE and TEE were 6.2±1.2 mm, 5.1±1.2 mm, and 5.5±1.3 mm, respectively. The measurement by RT-3DTEE was well correlated with that on the surgical specimens (P < 0.01), and the correlation was significantly better that of TTE and TEE (P < 0.05). The thickness of the pannus measured by RT-3DTEE also differed significantly from that by TTE and TEE (P < 0.05). For the diagnosis of pannus, the sensitivity, specificity, positive predictive value and negative predictive value of RT-3DTEE were 84.3% 92.1%, 93.5% and 81.4%, respectively, significantly higher than those of TTE (41.1%, 89.5%, 84.0% and 53.1%, respectively) and TEE (64.1%, 89.5%, 89.2% and 64.4%, respectively; P < 0.05). The pannus detected by RT-3DTEE occurred most commonly in the right anterior quadrant, with a circumference of 18.4±5.2 mm, an area of 0.79±0.28 cm2, and a mean transaortic pressure gradient of 38±12 mmHg. The pannus area measured by RT-3DTEE was well correlated with the mean transaortic pressure gradient of the prosthetic valve; the degree of valve occlusion could be assessed based on the measured pannus area and the mean transaortic pressure gradient of the prosthetic aortic valve. Conclusion RT-3DTEE can improve the sensitivity and specificity of ultrasonic diagnosis of pannus in the prosthetic aortic valve and allows accurate evaluation of the degree of valve obstruction caused by the pannus, thus providing reliable evidence to facilitate the diagnosis and treatment of the condition.

Rice and flour products are a type of major food in China, which is abundant in nutrients and humidity and thus is suitable for microbial growth. Spoilage microbes could shorten the shell life of food, and pathogenic microbes could cause food poisoning cases. In recent years, rapid detection on food borne microbes includes traditional and nucleic acids amplification methods, of which PSR is advantageous on sensitivity, specificity and reproducibility, showing a promising application prospect. In addition, viable but non-culturable (VBNC) microbial cells is incapable of being detected by “Golden standard” culturing methodology, and thus becomes an important threat for food safety. This review has summarized the major microbes in rice and flour products, currently available detection methodologies, as well as the biological characteristics and detection method of VBNC, which will provide significant information on further safety control of microbes in rice and flour products.

The rheological properties of cement grouts are significantly affected by the changes of the time and the water-cement ratio, which determine the diffusion state of grouts in rocks and soils and influence the outcome of projects. In this study, Portland cement grouts with water-cement ratios of 0.50, 0.55, 0.60, 0.65, 0.70, and 0.75 at six moments, including 0 minutes, 5 minutes, 10 minutes, 20 minutes, 30 minutes, and 60 minutes, were evaluated to figure out the comprehensive effect of the time and the water-cement ratio on the rheological properties of power-law cement grouts. The results showed that the water-cement ratio had a great influence on both the consistency coefficient and the rheological index of the power-law cement grouts. The former appeared to have a downward trend with the increase of the water-cement ratio, and the latter appeared to have an upward trend. There was a rising tendency between the time and the consistency coefficient, while the rheological index was less affected by time. The difference between its maximum and minimum values was within 5%. Combined with the perspectives of statistical theory, practical applicability, and accuracy, the exponential model was the optimal model for showing the relationship between the comprehensive effects of the time, water-cement ratio, and consistency coefficient of the power-law cement grouts. The linear model was the optimal model of the rheological index based on the comprehensive effect of time and the water-cement ratio. Based on this, a power-law rheological equation with consideration of the comprehensive effect of time and water-cement ratio was established. The research results could not only improve the rheological theory of power-law cement grouts but also provide technical support for engineering practice.

In September 1987 an accident occurred with a cesium chloride (CsCl) teletherapy source taken from a cancer therapy institute in Goiânia, Brazil. Misuse of the abandoned source caused widespread contamination of radioactive material (about 50 TBq of 137Cs) in the town of Goiânia. Decontamination of affected areas did lead to about 3,500 m3 of solid radioactive wastes, which were disposed in two near-surface repositories built in concrete in 1995. This paper documents a safety assessment of one of the low-level radioactive waste deposits containing 137Cs over a time period of 600 years. Using HYDRUS-1D, we first obtained estimates of water infiltrating through the soil cover on top of the repository into and through the waste and its concrete liners and the underlying vadose zone towards groundwater. Calculations accounted for local precipitation and evapotranspiration rates, including root water uptake by the grass cover, as well as for the effects of concrete degradation on the hydraulic properties of the concrete liners. We next simulated long-term water fluxes and 137Cs transport from the repository towards groundwater. Simulations accounted for the effects of 137Cs sorption and radioactive decay on radionuclide transport from the waste to groundwater, thus permitting an evaluation of potential consequences to the environment and long-term exposure to the public. Consistent with previous assessments, our calculations indicate that very little if any radioactive material will reach the water table during the lifespan of the repository, also when accounting for preferential flow through the waste.

This paper studies the reliability evaluation technology of regional energy Internet and represents a reliability evaluation method considering the optimal load reduction strategy. The application scenario of regional Energy Internet with power system as the core is built. The specific form is that multiple Integrated Energy systems are connected to the superior distribution network through the tie line. The reliability evaluation index system of power system and regional energy Internet is introduced. Based on the modelling of components in the regional energy Internet application scenario in this paper, the operation model and two-state Markov model are mainly established for the renewable energy power generation devices, energy coupling devices and energy storage devices in IES. The optimal load reduction models based on load classification are established for the faults of distribution network lines and the faults of IES internal components connected to the distribution network in regional energy Internet respectively. Through the construction of different application scenarios, the load reduction situation under different faults and different component parameters is analysed, and the corresponding reliability index calculation and result analysis are carried out.

We present a reliable calibration method using the constraint of 2D projective lines and 3D world points to elaborate the accuracy of the camera calibration. Based on the relationship between the 3D points and the projective plane, the constraint equations of the transformation matrix are generated from the 3D points and 2D projective lines. The transformation matrix is solved by the singular value decomposition. The proposed method is compared with the point-based calibration to verify the measurement validity. The mean values of the root-mean-square errors using the proposed method are 7.69×10−4, 6.98×10−4, 2.29×10−4, and 1.09×10−3 while the ones of the original method are 8.10×10−4, 1.29×10−2, 2.58×10−2, and 8.12×10−3. Moreover, the average logarithmic errors of the calibration method are evaluated and compared with the former method in different Gaussian noises and projective lines. The variances of the average errors using the proposed method are 1.70×10−5, 1.39×10−4, 1.13×10−4, and 4.06×10−4, which indicates the stability and accuracy of the method.

The Miniature Air Launched Decoy (MALD) flies cooperatively with a true target and construct unresolved targets within the radar beam. The unresolved targets and decoy result in echoes aliasing and observation merging, which causes serious measurement error and traditional track processing failure. Based on the analysis of jamming patterns and characteristics, the signal model of the unresolved targets is proposed. Combining jamming detection, echoes observation, and likelihood function characteristics, the proposed approach directly operates on the monopulse sum and difference returns and uses the particles propagating and evolving in the state space to obtain the conditional state probability density of the unresolved targets and decoy. This method effectively bypasses measurement extraction and parameter measurement, and realizes the joint tracking of the target and decoy. Furthermore, it provides the necessary conditions for target selection to the radar based on track and trajectory data. Simulation experiments illustrate the effectiveness of the proposed method.

Accuracy and precision of the analytical results for major and minor components in copper ores by the X-ray Fluorescence Spectrometry (XRF) fusion method can be seriously affected by the type of copper ore being analysed and the complex components it contains. The existing XRF analysis method is limited by the following factors: only having a small number of reference materials and ore types, single and wide scope of analysis not matching the actual samples, and low quality of pellet. In this study, we choose 24 ores of reference materials including copper, gold, silver, lead, zinc, molybdenum, copper and nickel which has a good range of copper content with common Cu levels. Lithium tetraborate-lithium metaborate-lithium fluoride was used as flux, the ratio of flux and sample being 30:1. Using LiBr as the release agent, the high quality melt sheet was prepared by adding later mixed flux which completely covered the release agent, but not by adding release agent after the pre-oxidation or during molten, as is the most common method used. The quantitative analytical method for determination of 16 elements including Cu, Zn, Pb, SiO2, Al2O3, TFe2O3, TiO2, MnO, CaO, K2O, MgO, Mo, Bi, Sb, Co and Ni in copper ore by X-ray fluorescence spectrometry with fused pellet was established. The method was verified by the analysis of the copper ore certified reference materials of GBW 07164 and GBW 07169, and the relative standard deviations (RSD) were from 0.1% to 5.4%. Analysis results of certified reference materials (GBW 07163, GBW 07170) which did not participate in regression were basically in good agreement with certified values. The results of Cu, Zn, Pb, Mo, Bi, Sb, Co and Ni for practical samples by the proposed method were consistent with those obtained by Inductively Coupled Plasma Spectrometry and other analysis methods. The method expanded the adaptability of ore matrix and improved value in the practical application.

The study revisited the community of inquiry (CoI) instrument for construct revalidation. To that end, the study used confirmatory factor analysis (CFA) to examine four competing models (unidimensional, correlated-factor, second-order factor, and bifactor models) on model fit statistics computed using parameter estimates from a statistical estimator for ordinal categorical data. The CFA identified as the optimal structure the bifactor model where all items loaded on their intended domains and the existence of the general factor was supported, essentially evidence of construct validity for the instrument. The study further examined the bifactor model using mostly model-based reliability measures. The findings confirmed the contributions of the general factor to the reliability of instrument scores. The study concluded with validity and reliability evidence for the bifactor model, supported the model as a valid and reliable representation of the CoI instrument and a fuller representation of the CoI theoretical framework, and recommended its use in CoI-related research and practice in online education.

In-wheel motor drives electric vehicles are becoming more and more widely used due to their unique advantages. This paper addresses the problem of in-wheel motor drive electric vehicle wheels slipping on low-attached roads. An active disturbance rejection controller is designed to control the inwheel motor torque and prevent the wheel slipping. The co-simulation is carried out between the adams and Matlab, and the results of simulation demonstrated that the controller which can prevent the wheel slipping effectively was perfect. The most important is that the controller can be implemented easily.

The SMS4 cryptosystem has been used in the Wireless LAN Authentication and Privacy Infrastructure (WAPI) standard for providing data confidentiality in China. So far, reliability has not been considered a primary objective in original version. However, a single fault in the encryption/decryption process can completely change the result of the cryptosystem no matter the natural or malicious injected faults. In this paper, we proposed low-cost structure-independent fault detection scheme for SMS4 cryptosystem which is capable of performing online error detection and can detect a single bit fault or odd multiple bit faults in coverage of 100 percent. Finally, the proposed techniques have been validated on Virtex-7 families FPGA platform to analyze its power consumption, overhead and time delay. It only needs 85 occupied Slices and 8.72mW to run a fault-tolerant scheme of SMS4 cryptosystem with 0.735ns of detection delay. Our new scheme increases in minimum redundancy to enhance cryptosystem’s reliability and achieve a better performance compared with the previous scheme.

Construction safety monitoring is an important approach to prevent collapse of scaffold shoring system during concrete formwork. In this article, the causes of the collapse of scaffold shoring system are investigated. A monitoring system based on the Internet of Things(IoT) is then proposed, consisting of wireless sensors, wireless monitor, wireless alarm, monitoring cloud platform and mobile client. The monitoring system is then put into practical application and has successfully detected the malfunction of the monitored system, which proves the efficiency and reliability of the monitoring system.