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Background: The purpose is to formulate a modified screening protocol for acute respiratory distress syndrome (ARDS) in patients with respiratory support based on saturation of pulse oximetry (SpO2) and inspired oxygen concentration (FiO2). Methods: This prospective observational study was conducted from August to October 2020 at the Department of Critical Care Medicine of Yijishan Hospital Affiliated with Wannan Medical College. All patients admitted during the study period and required arterial blood gas analysis and electrocardiogram monitoring were included in this study. Patients with contraindications to arterial puncture, methemoglobinemia, carbon monoxide poisoning, and other factors that could affect data collection were excluded. The demographic and clinical data, immediate percutaneous SpO2, FiO2, arterial oxygen partial pressure (PaO2), and respiratory rate were recorded; and the SpO2/FiO2 ratio (SFR) and PaO2/FiO2 ratio (PFR) values were calculated according to the above information. The patients were divided into two cohorts by random number table: the establishment cohort and the verification cohort. In the established part, data were divided into group H and group N according to whether SpO2 >97 %. For group H (SpO2 ≤97 %), the regression equation was established between SFR and PFR. For group N (SpO2 >97 %), the correlation between each observation data and PFR was analyzed. Then, a new diagnostic process was established, and the reliability was verified with the Berlin definition set as the gold standard for diagnosis and classification. Results: There were 341 patients were included. Among them, 161 patients were used to establish the model, and 180 patients were used to verify the validity of the model. In this new diagnosis progress, when SpO2 ≤97 %, if SFR ≤352, ARDS may exist; when SpO2 >97 %, if FiO2min >39 %, there may be ARDS. The sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of the new diagnosis progress for ARDS were 91.1 %, 76.7 %, 89.6 %, 79.6 %, and 83.9 %, respectively. Conclusion: The SpO2/FiO2 ratio demonstrates notable sensitivity and specificity in diagnosing ARDS, presenting as a credible alternative to PFR.Trail Registration Chinese Clinical Trial Registry Identifier: ChiCTR2000029217

Current lidar-inertial SLAM algorithms mainly rely on the geometric features of the lidar for point cloud alignment. The issue of incorrect feature association arises because the matching process is susceptible to influences such as dynamic objects, occlusion, and environmental changes. To address this issue, we present a lidar-inertial SLAM system based on the LIO-SAM framework, combining semantic and geometric constraints for association optimization and keyframe selection. Specifically, we mitigate the impact of erroneous matching points on pose estimation by comparing the consistency of normal vectors in the surrounding region. Additionally, we incorporate semantic information to establish semantic constraints, further enhancing matching accuracy. Furthermore, we propose an adaptive selection strategy based on semantic differences between frames to improve the reliability of keyframe generation. Experimental results on the KITTI dataset indicate that, compared to other systems, the accuracy of the pose estimation has significantly improved.

A profound comprehension of friction and wear mechanisms is essential for the design and development of high-performance polymeric materials for tribological application. However, it is difficult to deeply investigate the polymer friction process in situ at the micro/mesoscopic scale by traditional research methods. In recent years, molecular dynamics (MD) simulation, as an emerging research method, has attracted more and more attention in the field of polymer tribology due to its ability to show the physicochemical evolution between the contact interfaces at the atomic scale. Herein, we review the applications of MD in recent studies of polymer tribology and their research focuses (e.g., tribological properties, distribution and conformation of polymer chains, interfacial interaction, frictional heat, and tribochemical reactions) across three perspectives: all-atom MD, reactive MD, and coarse-grained MD. Additionally, we summarize the current challenges encountered by MD simulation in polymer tribology research and present recommendations accordingly, aiming to provide several insights for researchers in related fields.

Canine cachavirus is a novel parvovirus belonging to the genus Chaphamaparvovirus that was first detected in dogs in the United States. However, our knowledge of the prevalence and genetic characteristics of cachavirus is relatively limited. In this study, 325 canine fecal specimens collected from healthy and diarrheic dogs in northeastern China were screened with PCR. Twenty-two of the 325 (6.8%) samples were positive for cachavirus. The diarrhea samples showed high viral coinfection rates, and we detected coinfections with canine astrovirus (CaAstV) and cachavirus for the first time. A sequence analysis revealed that the Chinese cachavirus strains have point mutations in four consecutive amino acid codons relative to the original American strain. A codon usage analysis of the VP1 gene showed that most preferred codons in cachavirus were A- or T-ending codons, as in traditional canine parvovirus 2. A co-evolutionary analysis showed that cachavirus has undergone cospeciation with its hosts and has been transmitted among different host species. Our findings extend the limited cachavirus sequences available, and provide detailed molecular characterization of the strains in northeastern China. Further epidemiological surveillance is required to determine the significance and evolution of cachavirus.

Corruption is one of the thorny issues in any modern society, especially in China. The new leadership of the Communist Party of China (CPC) led by President Xi Jinping robustly initiated an anti-corruption campaign as soon as he took over as the party chief in the end of 2012. Several legal reforms aiming at fighting harder against corruption crimes drew attention from home and abroad, including foreign investors. These reforms include the enactment of the National Supervision Law in 2018, the establishment of a special proceeding of confiscation of illegal gains in the 2012 amendment to Criminal Procedure Law (CPL), and the introduction of “trial in absentia” procedure in the 2018 CPL amendment. Another ongoing reform is the corporate compliance non-prosecution pilot. China used to adopt a dual-penalty approach upon corporate crimes, imposing punishments on both the directly responsible persons and the enterprises. However, the traditional sanction against enterprises tends to cause secondary harms to the society. For example, when a corporation goes bankrupt, thousands of innocent people will be unemployed. Therefore, non-prosecution might be a more effective way of ensuring corporate compliance as well as minimalizing the harms mentioned above. This paper explores the anti-corruption mechanisms Chinese government has created or improved over the past decade and attempts to provide a bird’s eye view of China’s anti-corruption law.

Carbon flow in forest products trade will affect the report of a country's carbon stock. This will have an impact on a country's contribution of carbon flows. Based on the analysis of China’s forest product trade, this paper uses the stock-change approach, the production approach and the atmospheric-flow approach to calculate the changes of China's forest products trade carbon flows. Different carbon flow measurement approaches have very different results. From the perspective of the contribution of forest products to carbon flow, the production approach of calculation for forest products trade carbon flow has the largest contribution to atmospheric carbon flows. However, the calculation results of the stock-change approach and the atmospheric-flow approach are just the opposite, that is, the calculation for forest products trade has a negative contribution to China's carbon sinks, and forest products trade has become a source of carbon emissions.

Bi-Sb alloys are appealing anode materials for potassium ion batteries (PIBs) but challenged by their enormous volumetric variation during operation. Herein, a facile one-step dealloying protocol was devised and utilized to prepare the Bi-Sb alloys that manifest an exotic bicontinuous hierarchical nanoporous (np) microstructure ideal for volume-change mitigation and K+ transport percolation. The growth mechanism fostering the peculiar morphology of the np-(Bi,Sb) alloys was investigated and clarified via operando X-ray (XRD) and ex-situ scanning electron microscopy (SEM). In particular, the np-Bi6Sb2 electrode, optimized for comprehensive electrochemical performance, achieves decent reversible capacities and a superior lifespan, as benchmarked with the monometallic references and other Bi-Sb alloy electrodes. The (de)potassiation mechanism of the np-(Bi,Sb) alloys was studied by operando XRD and further rationalized by density functional theory (DFT) calculations, whereby a homogeneous (segregation-free) and robust two-step electrochemically-driven phase transformations’ catenation of (Bi,Sb) ↔ K(Bi,Sb)2 ↔ K3(Bi,Sb) was reliably established to substantiate the outstanding reversibility of the np-(Bi,Sb) anodes in PIBs.

The use of augmented reality head-up displays (AR-HUD) in automobile safety driving has drawn more and more interest in recent years. An AR-HUD display system should be developed to fit the vehicle and the complicated traffic environment in order to increase the driver’s driving concentration and improve the man–vehicle synchronization. In this article, we suggest an AR-HUD display system with dual-layer virtual-image displays for the near field and far field, as well as further research and design of the adjustment system for multi-depth displays of far-field images. It also examines the EYEBOX horizontal adjustment margin of the dual light path. The analysis results show that the scale of EYEBOX is 120 × 60 mm2, the modulation transfer function (MTF) of near-field light path > 0.2 @ 6.7 lp/mm, and the MTF of far-field optical path > 0.4 @ 6.7 lp/mm. The distortion of the near-field optical path is less than 0.86%, and that of the far-field optical path is less than 2.2%. By modifying the folding mirror, the far-field optical path creates an 8 m to 24 m multi-depth virtual picture display. Image quality can be maintained when the near-field and far-field optical paths are moved horizontally by 25 mm and 100 mm, respectively. This study offers guidelines for the multi-depth display, EYEBOX horizontal adjustment, and optical layout of augmented reality head-up displays.

Due to the poor stability of the loose sandy soil layer, if the support force is not properly controlled during the construction process of the shield tunnel using the earth pressure balance method, it is easy to cause the ground to collapse or uplift. Therefore, understanding the support force of the excavation surface of shield tunneling in sandy soil layer is very vital to ensure the stability of the excavation surface. Firstly, it is assumed that the damaged soil is a three-dimensional wedge and a modified three-dimensional wedge in the active and passive failure modes, respectively. The shallow soil pressure theory and the soil plastic limit equilibrium theory are derived by analyzing the stress distribution on the damaged soil. The equation for revealing the inner essence between the support force of the shield excavation surface and excavation surface displacement under the condition of sand-covered soil is used. Secondly, the numerical simulation method analyzes the displacement of the excavation surface when the support force changes under different working conditions, and the relationship curve between the excavation surface support force and the shield tunneling displacement is obtained. The comparison and analysis between the numerical simulation calculation and the theoretical analysis indicate that the deduced calculation equation for the excavation surface support force based on the displacement earth pressure is reasonable.

Aim of study: To investigate the content, contamination levels and potential sources of five heavy metals (Hg, Pb, Cd, Cr, As) in sewage sludge from eight wastewater treatment plants (W1 to W8). Area of study: Wuhu, located in southeastern Anhui Province, southeastern China. Material and methods: The sewage sludge pollution assessment employed the single-factor pollution index, Nemerow’s synthetic pollution index, monomial potential ecological risk coefficient and potential ecological risk index. The potential sources among the five heavy metals were determined using the Pearson’s correlation analysis and principal component analysis (PCA). Main results: The mean concentrations of the heavy metals were 0.27 mg/kg (Hg), 70.78 mg/kg (Pb), 3.48 mg/kg (Cd), 143.65 mg/kg (Cr) and 22.17 mg/kg (As). W1, W5 and W6 sewage sludge samples showed the highest levels of heavy metal contamination, and cadmium had the highest contamination level in the study area. Pearson’s correlation analysis and PCA revealed that Pb and Cd mainly derived from traffic emissions and the manufacturing industry and that As and Cr originated from agricultural discharges. Research highlights: The pollution of cadmium in Wuhu should be controlled preferentially. The heavy metal pollution of W1, W5 and W6 sewage treatment plants is relatively high, they should be key prevention targets.

In addition to the micro-topography of machined surfaces, plastic deformation is an important factor affecting the machined surface integrity and the fatigue performance of specimens. For 20Cr and TC17 materials, the effect law of milling surface plastic deformation on high- and low-cycle fatigue performance of specimens was studied. Experimental results show that the effect law of milling surface plastic deformation on high- and low-cycle fatigue performance of specimens is different. When the high-cycle fatigue life is about 2 × 105 cycles, severe surface plastic deformation can increase the maximum stress suffered by TC17 specimens from 1060 MPa to 1080 MPa; when the low-cycle fatigue life is about 6 × 104 cycles, severe surface plastic deformation can reduce the maximum stress suffered by 20Cr specimens from 680 MPa to 660 MPa. Therefore, severe surface plastic deformation can improve the high-cycle fatigue performance and, on the contrary, it has a negative effect on the low-cycle fatigue performance. Combined with the analysis of the surface integrity index and the fatigue fracture topography of specimens, it is concluded that the machined surface plastic deformation significantly reduces the plastic deformation capacity of surface layer material and enhances the stress concentration phenomenon caused by the surface micro-topography, so that when a specimen is subjected to a large load, it is very easy to make microcracks appear on the machined surface and form the “over-plastic deformation” phenomenon, resulting in a sharp decrease in the low-cycle fatigue performance of specimens. This suggests that the plastic deformation degree of machined surfaces needs to be optimized depending on the magnitude of the working load and the micro-topography.

Utilization of waste dregs, e.g. Huaimi dregs, is an important issue. Huaimi is a traditional Chinese medicine and 20,000 tons of dregs are annually produced. This study optimized the production of L-lactic acid through solid-state fermentation of Huaimi dregs using uniform and orthogonal experimental designs. Among three tested parameters, fermentation time and substrate ratio (wheat bran:Huaimi dregs) were found to have a significant effect on the production of lactic acid. Using fermentation time of 41.6 h, substrate ratio of 4.26:1, inoculum size of 6.1% and fermentation temperature of 28 °C, 1 kg Huaimi dregs could produce 286.6 mg lactic acid.

As a core component of SPN block cipher and hash function, diffusion layer is mainly introduced by matrices built from maximum distance separable (MDS) codes. Up to now, most MDS constructions require to perform an equivalent or even exhaustive search. In this paper, we study the cyclic structure of rotational-XOR diffusion layer, a commonly used diffusion primitive over (

The development of high efficient stacks is critical for the wide spread application of proton exchange membrane fuel cells (PEMFCs) in transportation and stationary power plant. Currently, the favorable operation conditions of PEMFCs are with single cell voltage between 0.65 and 0.7 V, corresponding to energy efficiency lower than 57%. For the long term, PEMFCs need to be operated at higher voltage to increase the energy efficiency and thus promote the fuel economy for transportation and stationary applications. Herein, PEMFC single cell was investigated to demonstrate its capability to working with voltage and energy efficiency higher than 0.8 V and 65%, respectively. It was demonstrated that the PEMFC encountered a significant performance degradation after the 64 h operation. The cell voltage declined by more than 13% at the current density of 1000 mA cm−2, due to the electrode de-activation. The high operation potential of the cathode leads to the corrosion of carbon support and then causes the detachment of Pt nanoparticles, resulting in significant Pt agglomeration. The catalytic surface area of cathode Pt is thus reduced for oxygen reduction and the cell performance decreased. Therefore, electrochemically stable Pt catalyst is highly desirable for efficient PEMFCs operated under cell voltage higher than 0.8 V.

The tweakable Even-Mansour construction generalizes the conventional Even-Mansour scheme through replacing round keys by strings derived from a master key and a tweak. Besides providing plenty of inherent variability, such a design builds a tweakable block cipher from some lower level primitive. In the present paper, we evaluate the multi-key security of TEM-1, one of the most commonly used one-round tweakable Even-Mansour schemes (formally introduced at CRYPTO 2015), which is constructed from a single n-bit permutation P and a function f(k, t) linear in k from some tweak space to {0, 1} n. Based on giant component theorem in random graph theory, we propose a collision-based multi-key attack on TEM-1 in the known-plaintext setting. Furthermore, inspired by the methodology of Fouque et al. presented at ASIACRYPT 2014, we devise a novel way of detecting collisions and eventually obtain a memory-efficient multi-key attack in the adaptive chosen-plaintext setting. As important applications, we utilize our techniques to analyze the authenticated encryption algorithms Minalpher (a second-round candidate of CAESAR) and OPP (proposed at EUROCRYPT 2016) in the multi-key setting. We describe knownplaintext attacks on Minalpher and OPP without nonce misuse, which enable us to recover almost all O(2n/3) independent masks by making O(2n/3) queries per key and costing O(22n/3) memory overall. After defining appropriate iterated functions and accordingly changing the mode of creating chains, we improve the basic blockwiseadaptive chosen-plaintext attack to make it also applicable for the nonce-respecting setting. While our attacks do not contradict the security proofs of Minalpher and OPP in the classical setting, nor pose an immediate threat to their uses, our results demonstrate their security margins in the multi-user setting should be carefully considered. We emphasize this is the very first third-party analysis on Minalpher and OPP.

The article delves into the reform of lay participation in China's judicial system, examining the historical background, recent legislative developments, and the challenges faced in implementing these reforms. It explores China's adoption of a mixed tribunal system akin to civil law countries, analyzes the People's Assessors Law enacted in 2018, and reflects on the limitations and future prospects of lay participation in China's legal system.