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ObjectiveTo identify high-risk factors and high-risk process of nosocomial infection， and then take targeted prevention and control measures to improve nosocomial infection management.MethodsWe identified and determined the risk factors associated with nosocomial infection by using an expert brainstorming method， and then conducted risk assessment of the factors in the outcomes and process by using a semi-quantitative method.ResultsA total of 31 experts participated in the risk factor assessment. Risk assessment scores showed that nosocomial infection due to multi-drug resistant bacteria was the highest risk in the outcomes of nosocomial infection. Lack of isolation for airborne/droplet transmission， needle/sharp instrument injury， inadequate identification of infection risk and response measures in construction engineering， and insufficient implementation of infection control system were extremely high risk factors in the process of nosocomial infection.ConclusionPrevention and control should be strengthened on multi-drug resistant bacteria and catheter-related infections. The role of multidisciplinary team （MDT） in the prevention and control of nosocomial infection should be enhanced in medical practice. Risk assessment may facilitate the resource allocation and improve hand hygiene behavior.

Liability attribution for crashes involving automated vehicles (AVs), if applied improperly, is a factor which can potentially hinder acceptance. The present study investigated the impact of liability attribution on intention to buy an AV. A vignette-based survey was implemented with a hypothetical crash similar to the 2018 Uber crash (which was jointly caused by driver distraction and the malfunctioning of the automated system) leading to a pedestrian's fatality. Respondents (N = 1524) chose their preferred liability attribution, ranging from human driver exclusively liable to AV manufacturer exclusively liable. Respondents were then randomly allocated to different conditions of actual liability attribution by the local authority. These conditions were then combined into, negative misattribution (the authority assigned more liability to the human driver, compared to the respondent), positive misattribution (the authority assigned less liability to the human driver), and no misattribution. Negative misattribution negatively affected intention to buy; however, positive misattribution did not have a significant impact. The results of a multiple-mediator model indicated that negative misattribution affects intention to buy through the mediating effects of trust, negative affect, and crash acceptability. Theoretical and practical implications of our results are discussed. [ABSTRACT FROM AUTHOR]

In order to reduce the thickness of the frozen shaft and avoid shaft cracking caused by hydration heat of mass concrete, C100 high-performance concrete is adopted as the deep shaft material in the west air shaft of Zhaogu No.2 mine. After multiple and multi-site comparison of raw materials, P.II52.5 portland cement, basalt gravel with compressive strength of 148 MPa, mechanism sand without fineness modulus of 2.8 and low-temperature early-strength collapse-protected polycarbarate high-performance water reducer were determined as the raw materials for C100 high-performance concrete. By mixture ratio test, the C100 concrete cement∶ sand∶ gravel∶ admixture∶ mineral powder∶ water∶ water reducing agent is 395∶600∶1 100∶120∶100∶105∶29. Ultimately, no cracks appeared in the borehole wall of C100 freezing section, which ensured good performance of pressure bearing and water sealing. After 28 days of shaft lining casting, field sampling was conducted to measure the strength. The test results showed that the C100 high-performance concrete reached 117% of the designed strength level, which exceeded the standard of 1.15 times of the designed strength as the minimum requirement for the concrete strength of shaft engineering.

Urban public transportation is inseparably related to people’s travel and life. Prioritizing the development of public transportation is a major national policy proposed by the Chinese government, especially to actively promote the development of intelligent public transportation systems. Developing and building advanced intelligent public transport operation and scheduling management system, designing efficient, flexible and low-cost operation and scheduling mode, improving the management level and service quality of public transport enterprises, and thus improving the road traffic condition of the whole city, is undoubtedly the future development direction of public transport enterprises. This paper combines the problems of bus operation and scheduling in China at the present stage, and proposes the operation and scheduling model and method of the intelligent urban public transportation planning system, with a view to realizing a flexible public transportation operation model suitable for different service situations and providing systematic theoretical support for solving the imbalance between supply and demand of public transportation.

A novel material, i.e. 2.5D three-harness-twill warp-reinforced woven composites (2.5D-THT-WR-WC), is proposed, which has wide engineering applications. In this work, geometrical relationships with different meso features are discussed through X-CT characterization. On this basis, six unit-cell models with different meso geometrical features are established considering different weft yarn arrangement densities MF, and numerical simulations are carried out combined with a developed progressive damage model. Comparison with the experimental results shows that the maximum prediction errors of modulus and strength are 6.3% and 11.7%, respectively. Therefore, the developed numerical simulation model can reasonably predict the mechanical behavior of 2.5D-THT-WR-WC. Additionally, as the MF increases, the mechanical properties in the warp and weft directions decrease and increase, respectively, owing to the inclination angle and the extrusion condition between adjacent layers of the binder yarns. This work provides a design reference for the structural application of 2.5D-THT-WR-WC, which has a significant engineering value. [ABSTRACT FROM AUTHOR]

High-power diesel engine turbochargers predominantly utilize floating ring bearings as their primary supporting components. To further enhance their load capacity, multi-lobe noncircular bearings have been progressively employed. This study focuses on the investigation of noncircular three-lobe SFRBs (semi-floating ring-bearing structures) in marine turbochargers. Employing the half-step center Finite Difference Method (FDM) and the Newton–Raphson iterative procedure, the impact of operational parameters such as the journal speed, external load, oil supply pressure, and oil supply temperature on the static and dynamic characteristics of the inner oil film is analyzed. Subsequently, the accuracy of the theoretical model is validated through a comparative analysis of simulation results obtained from Dyrobes and Fluent. The findings indicate that as the oil supply pressure and temperature increase, the temperature rise and maximum oil film pressure of the three-lobe SFRBs gradually decrease, while the oil film thickness progressively increases, thereby significantly improving the lubrication state. The load capacity of the three-lobe SFRBs is primarily sustained by the bottom tile, where wall friction is most likely to occur. Additionally, within the actual speed range, the stiffness and damping of the three-lobe SFRBs exhibit noticeable nonlinear characteristics. [ABSTRACT FROM AUTHOR]

This study investigates the responses of the depositional environments of Soda Lake sediments to climatic shifts from the Last Glacial Maximum to the Holocene epoch based on the results of major and trace elements of the North Soda Lake (NSL) NSL1A core. The NSL1A core records the sedimentary evolution of the Soda Lake watershed since at least 25 cal ka BP. Element analyses provide evidence that Soda Lake sediments are mostly derived from marine sequences in the Southern Coast Ranges of California. Variation in proxies for paleoweathering, paleoclimate, paleosalinity, paleoproductivity, paleoredox, and water depth is utilized to reconstruct the evolution of the sedimentary environment. The Chemical Index of Alteration (CIA) values indicate low to moderate chemical weathering in the sediment source regions. Paleoredox proxies indicate that the NSL1A core formed in a mainly subreduction environment. The NSL1A core is divided into four zones based on the results of the proxies. Zone 4 (5.0–5.8 m) of the sediment core indicates stable hydroclimatic conditions with low and constant sand and silt content, suggesting a warm and relatively humid environment. Zone 3 (3.35–5.0 m) represents the early half of the Last Glacial Maximum interval and a high lake stand. The elevated sand content suggests postflood events due to the northerly migration of westerly storm tracks. Zone 2 (1.075–3.35 m) reveals nuanced changes, including decreasing salinity, slight increases in wetness, detrital trace metals, and paleoproductivity. These subtle shifts suggest a multifaceted environmental evolution: a trend toward wetter conditions alongside a prolonged shift from cooler to warmer periods. Zone 1 (0.15–1.075 m) spans the Lateglacial to Holocene transition as well as Early and Middle Holocene, marked by significant hydrologic and ecologic variability including rapid warming during the Bølling–Allerød and rapid cooling linked to the Younger Dryas. [ABSTRACT FROM AUTHOR]

As an important component of inlet and exhaust mufflers, the acoustic characteristics of perforated components are inevitably affected by the flow of air. Therefore, obtaining the acoustic impedance of the perforated element under airflow conditions is a prerequisite for accurate calculation of the muffler's muffling performance. In this work, the frequency domain linear Navier–Stokes (L-NS) method is used to extract the acoustic impedance of perforated plates under grazing flow. The predicted perforated acoustic impedance is consistent with the calculation results of published acoustic impedance expression, and the impedance boundary condition is defined to calculate the transmission loss (TL) of the perforated muffler, which agrees well with the experimental results and verifies the accuracy of the method. The effect of perforation angles on the transmission loss of mufflers in different Mach numbers (Ma) and aperture plate thickness ratio (d h/ t p) is analyzed by the frequency domain L-NS method. The results show that when 1≤ d h/ t p<2 and Ma ≤2, the effect of perforation angles on the muffler performance is obvious, and the angle tilted upstream shifts the resonant frequency to a lower frequency while its corresponding peak value is also increased. As an engineering application, it has certain significance for the prediction of muffler muffling performance and the regulation of the muffling frequency band. [ABSTRACT FROM AUTHOR]