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The heat treatment process is a vital step for manufacturing high-speed railway spring fasteners. In this study, orthogonal experiments were carried out to obtain reliable optimised heat treatment parameters through a streamlined number of experiments. Results revealed that a better comprehensive mechanical performance could be obtained under the following combination of heat treatment parameters: quenching temperature of 850 °C, holding time of 35 min, medium of 12% polyalkylene glycol (PAG) aqueous solution, tempering temperature of 460 °C, and holding time of 60 min. As one of the most important testing criteria, fatigue performance would be improved with increasing strength. Additionally, a high ratio of martensite to ferrite is proven to improve the fatigue limit more significantly. After this heat treatment process, the metallographic microstructure and mechanical properties satisfy the technical requirements for the high-speed railway practical operation. These findings provide a valuable reference for the practical forming process of spring fasteners.

Summary Statement Simulation played a critical role in our institution's response to the COVID-19 pandemic in New York City. With the rapid influx of critically ill patients, resource limitations, and presented safety concerns, simulation became a vital tool that provided solutions to the many challenges we faced. In this article, we describe how simulation training was deployed at our institution throughout the course of the pandemic, which included the period of our medical surge. Simulation helped refine protocols, facilitate practice changes, uncover safety gaps, and train redeployed healthcare workers in unfamiliar roles. We also discuss the obstacles we encountered with implementing simulations during the pandemic, the measures we took to adapt to our limitations, and the simulation strategies and end products that were derived from these adaptations.

National data on patient characteristics, treatment, and outcomes of critically ill coronavirus disease 2019 (COVID-19) solid organ transplant (SOT) patients are limited. We analyzed data from a multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units (ICUs) at 68 hospitals across the United States from March 4 to May 8, 2020. From 4153 patients, we created a propensity score matched cohort of 386 patients, including 98 SOT patients and 288 non-SOT patients. We used a binomial generalized linear model (log-binomial model) to examine the association of SOT status with death and other clinical outcomes. Among the 386 patients, the median age was 60 years, 72% were male, and 41% were black. Death within 28 days of ICU admission was similar in SOT and non-SOT patients (40% and 43%, respectively; relative risk [RR] 0.92; 95% confidence interval [CI]: 0.70-1.22). Other outcomes and requirement for organ support including receipt of mechanical ventilation, development of acute respiratory distress syndrome, and receipt of vasopressors were also similar between groups. There was a trend toward higher risk of acute kidney injury requiring renal replacement therapy in SOT vs. non-SOT patients (37% vs. 27%; RR [95% CI]: 1.34 [0.97-1.85]). Death and organ support requirement were similar between SOT and non-SOT critically ill patients with COVID-19.

Supplemental material, sj-docx-1-trr-10.1177_03611981221121270 for Probabilistic Prediction of Collisions between Cyclists and Vehicles Based on Uncertainty of Cyclists’ Movements by Di Pan, Yong Han, Qianqian Jin, Jin Kan, Hongwu Huang, Koji Mizuno and Robert Thomson in Transportation Research Record

A new kavalactone, 4'-hydroxyl dihydro-5, 6-dehydrokavain (1) was isolated from the petroleum ether partition of leaves of Alpinia zerumbet (Pers.) Burtt. et Smith, together with four known kavalactone dimers, rel-1,trans-3-bis-(4-methoxy-2-oxopyran-6-yl)-cis-2,trans-4-diphenyl cyclobutene (2), aniba dimer A (3), aniba dimer C (4), 6,6'-(3,4-diphenylcyclobutane-1,2-diyl)bis(4-methoxy-2H-pyran-2-one (5). The structure of compound 1 was characterized by its MS, 1D-NMR, and 2D-NMR data, and the structures of the known compounds were determined by comparison of their spectroscopic data with those reported by the literatures. The obtained compounds were evaluated for their protective activities on human umbilical vein endothelial cells (HUVECs) damaged by high glucose (35 mM, cell viability at 70.10%). Compounds 3 and 5 could increase the cell viability at the concentration of 12.5 μΜ (83.12%) and 25 μΜ (75.02%), whereas at the concentration of 12.5 μΜ, compounds 1, 2, and 4 didn’t reverse cell damage (cell viability at 38.58%, 54.80% and 58.16%).

Supplemental material, sj-docx-1-pid-10.1177_09544070221128173 for Comparative analysis of AEB effectiveness based on typical and atypical scenarios of electric two-wheeler accidents in China by Di Pan, Yong Han, Qianqian Jin, He Wu, Bingyu Wang, Hongwu Huang and Koji Mizuno in Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering

Additional file 1: Sepsis Subphenotyping Based on Organ Dysfunction Trajectory.

Supplemental material, sj-docx-1-pid-10.1177_09544070221128173 for Comparative analysis of AEB effectiveness based on typical and atypical scenarios of electric two-wheeler accidents in China by Di Pan, Yong Han, Qianqian Jin, He Wu, Bingyu Wang, Hongwu Huang and Koji Mizuno in Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering

Supplemental material, sj-docx-1-trr-10.1177_03611981221121270 for Probabilistic Prediction of Collisions between Cyclists and Vehicles Based on Uncertainty of Cyclists’ Movements by Di Pan, Yong Han, Qianqian Jin, Jin Kan, Hongwu Huang, Koji Mizuno and Robert Thomson in Transportation Research Record

Antimalarial drugs Dihydroartemisinin (DHA) and chloroquine phosphate (CQ) exhibit evident anti-cancer activity, particularly as combination therapy. DHA and CQ combination therapy has been proved to exhibit higher cytotoxic effect in tumor cells and lower toxicity to normal cells than combination of artemisinin derivatives (ARTs) and anticancer chemotherapy drugs. However, different physiochemical properties of DHA and CQ, leading to distinctive in vivo outcomes, considerably limited their synergistic effect in cancer treatment. Herein, we developed a lipid nanoparticle (LNP) for co-delivery of DHA and CQ to inhibit proliferation and metastasis of colorectal cancer. Considering the beneficial effects of acid/reactive oxide species (ROS)-sensitive phospholipids and targeting ligands for colorectal cancer cells, an RGD peptide-modified pH/ROS dual-sensitive LNP loaded with DHA and CQ (RLNP/DC) was prepared. It exhibited optimal cytotoxicity and suppression of invasion and metastasis in HCT116 cells in vitro, attributable to irreversible upregulation of intracellular ROS levels, downregulation of VEGF expression, and upregulation of paxillin expression. A mouse model of orthotopic metastasis of colorectal cancer was established to evaluate anti-proliferation and anti-metastasis effects of RLNP/DC in vivo. Thus, an optimized nanoplatform for DHA and CQ combination therapy was developed in this study that offered potential antitumor efficacy against colorectal cancer.

At present, the traditional ICP (Iterative Closest Point) algorithm used by TOF (Time-Of-Flight) cameras has the problem of high time-consuming in nearest point search process, resulting in low data update rate. Therefore, based on the characteristics of the data structure of the ICP algorithm, a multi-stage pipeline acceleration system is proposed, and the point cloud registration algorithm used in this system is studied. Firstly, design multiple units to store point cloud data and serve as the main search module. Secondly, make each group of units perform parallel operations, input the stored point clouds into their respective calculation modules, select a model point, traverse all query points, and perform subtraction. Then replace the model point and repeat the process until all model points are calculated. Finally, the query point corresponding to the minimum value in each model point difference data is selected and the model point is output as a point pair to the CPU to complete the final algorithm iteration. The experimental results show that at 30000 points, a single closest point search takes 25.65ms; at 20000 points, a single closest point search takes 11.65ms; at 10000 points, a single closest point search takes 2.88ms. It basically meets the requirements of TOF camera on-orbit measurement for the stability and reliability of point cloud registration and high data update rate.

In high dynamic conditions, star spot exhibits a tailing phenomenon, which makes it impossible to accurately extract the star centroid. Adjusting the exposure time can shorten the tail length but it will reduce the energy received by the detector, which also makes it difficult to extract the star target. Aiming at the above two problems, this paper proposes a star spot centroid extraction method under high dynamic conditions based on different hash algorithm. The method is divided into three steps. Firstly, establish a mathematical model of dynamic star spots. Then using difference hash algorithm and Hamming distance to realize coarse positioning of star targets in star tracking window. Finally, adopt threshold segmentation and connected domain method to extract star spot centroid in the coarse location area. The experimental results show that the proposed method can adapt to various exposure time, making the star sensor realize the stable tracking at the angular velocity of 3°/s. When the exposure time is 50ms and the angular velocity is 3°/s, the angular distance error is 13 arcseconds, the average extraction rate is 96%, which is 29.6% and 29.7% better than the traditional method.

With electricity as the main power energy, the UAV has been affected by the impact of battery storage on the flight time and flight time, which makes the UAV need to constantly replace the battery to ensure the long-term operation. The automatic endurance system takes the remaining power of the UAV as the independent variable, and the average value of the flight data of the UAV battery for nearly three times as the judgment basis. It realizes the automatic navigation in the UAV area, charges the base station after landing accurately, and improves the endurance time of the UAV.

IMPORTANCE: Therapies that improve survival in critically ill patients with coronavirus disease 2019 (COVID-19) are needed. Tocilizumab, a monoclonal antibody against the interleukin 6 receptor, may counteract the inflammatory cytokine release syndrome in patients with severe COVID-19 illness. OBJECTIVE: To test whether tocilizumab decreases mortality in this population. DESIGN, SETTING, AND PARTICIPANTS: The data for this study were derived from a multicenter cohort study of 4485 adults with COVID-19 admitted to participating intensive care units (ICUs) at 68 hospitals across the US from March 4 to May 10, 2020. Critically ill adults with COVID-19 were categorized according to whether they received or did not receive tocilizumab in the first 2 days of admission to the ICU. Data were collected retrospectively until June 12, 2020. A Cox regression model with inverse probability weighting was used to adjust for confounding. EXPOSURES: Treatment with tocilizumab in the first 2 days of ICU admission. MAIN OUTCOMES AND MEASURES: Time to death, compared via hazard ratios (HRs), and 30-day mortality, compared via risk differences. RESULTS: Among the 3924 patients included in the analysis (2464 male [62.8%]; median age, 62 [interquartile range {IQR}, 52-71] years), 433 (11.0%) received tocilizumab in the first 2 days of ICU admission. Patients treated with tocilizumab were younger (median age, 58 [IQR, 48-65] vs 63 [IQR, 52-72] years) and had a higher prevalence of hypoxemia on ICU admission (205 of 433 [47.3%] vs 1322 of 3491 [37.9%] with mechanical ventilation and a ratio of partial pressure of arterial oxygen to fraction of inspired oxygen of

Introduction: Cervical cancer is the second largest tumor disease threatening female reproductive tract health. AS2O3 is a multi-directional and multi-target anti-cervical cancer drug. It can be combined with platinum drugs to treat cervical cancer. The literatures of AS2O3 combined with platinum drugs related to cervical cancer have shown inconsistent results, and there is currently no high quality of systematic review to evaluate the effects of AS2O3 combined with platinum drugs in cervical cancer patients. Methods and analysis: English and Chinese literature about AS2O3 combined with platinum drugs treatment for cervical cancer published before August 31, 2020 will be systematic searched in PubMed, Embase, Web of Science, Cochrane Library, Open Grey, Clinicaltrials.gov, Chinese Clinical Trial Registry, WANFANG, VIP Chinese Science and Technology Journal Database, CNKI, Chinese biomedical document service system (SinoMed). Only randomized controlled trials (RCTs) of patients with cervical cancer will be included. Literature screening, data extraction, and the assessment of risk of bias will be independently conducted by 2 reviewers, and the 3rd reviewer will be consulted if any different opinions existed. Clinical total effective rate, adverse events, SCCAg, CYFRA21-1, quality of life, and immune function will be evaluated. Systematic review and meta-analysis will be produced by RevMan 5.3 and Stata 14.0. This protocol reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) statement, and we will report the systematic review by following the PRISMA statement. Results: The current study is a protocol for systematic review and meta-analysis without results, and data analysis will be carried out after the protocol. We will share our findings in the fourth quarter of 2021. Conclusion: Efficacy and safety of AS2O3 combined with platinum drugs in the treatment of cervical cancer will be assessed. The results will be published in a public issue journal to provide evidence-based medical evidence for Obstetrician and Gynecologists to make clinical decisions. Ethics and dissemination: Ethical approval is not required as the review is a secondary study based on published literature. The results of the study will be published in peer-reviewed publications and disseminated electronically or in print. Protocol registration number: INPLASY202080130.

The equivalent parameters of converter for power flow calculation will be affected by the actual operating conditions. Meanwhile, the power flow calculation models of ACDC hybrid distribution networks are different. Aiming at above problems, this paper proposes a power flow calculation method of chain-type AC-DC hybrid distribution network based on converter parameter identification. First, the online parameters identification of AC-DC and DC-DC converter for power flow calculation is realized based on the least square method. Furthermore, the identified values are brought into the general power flow calculation model of AC-DC system, and then the Newton- Raphson algorithm is used to solve it. Thus, the power flow calculation of the chain AC-DC hybrid distribution network is realized. Finally, the simulation results show the effectiveness of the proposed method and the power flow calculation results after online identification are more accurate.

Graphene-based strain sensors have attracted tremendous interest due to their potential application as intelligent wearable sensing devices. However, for graphene-based strain sensors, it is found that the sensing property at the beginning of the tensile cycle is not stable. Concretely, the peak resistance value gradually declines in the first dozens of cycles in every cyclic test. This is a problem that obviously affects the measurement accuracy but is rarely investigated so far. In this paper, this phenomenon is for the first time systematically studied. According to the reliable experimental results, it can be concluded that the decline of resistance is caused by the evolution of wrinkle morphologies in the graphene layer, which is essentially attributed to the temporary slippage of the graphene sheets under external stress. Based on the analyzed mechanism, a targeted improvement solution was proposed and verified. By the combined effects of polydopamine and Ni2+, the slippage among the rGO sheets was suppressed and a strain sensor with excellent sensing stability was obtained as expected. Furthermore, the sensitivity of the modified sensor was six times higher than that of the pristine one due to the change in the crack form, demonstrating it to be an effective method to obtain a graphene-based strain sensor with comprehensively high performance.

Background Computer-assisted electroencephalography (EEG) systems may improve the likelihood of detecting abnormal EEGs in adult patients with severe disease. Case presentation We implemented long-range EEG monitoring in a patient with large hemispheric infarction (LHI) and explored its real-time changes in reflecting the patient's brain function. The bands of Alpha, Beta, Delta, Theta, DAR (Delta/Alpha), DTABR (Delta+Theta/Alpha+Beta), and brain symmetry index (BSI) were calculated as a ratio of total power. The test results showed that this patient presents a progressive worsening trend and developed brain herniation. The sigh at the electrophysiological level of brain herniation could be seen 6 h in advance based on the quantitative EEG (QEEG) parameters test. We calculated QEEG at both C3 and C4, electrode locations simultaneously, and the results showed that the trend of QEEG at both electrodes was consistent with the global, affected, and unaffected side. Conclusions QEEG parameters can reflect the trend of LHI patients in real-time and may predict the occurrence of LHI brain herniation. For LHI patients, monitoring with fewer EEG electrodes can be tried to predict the changes in conditions.

Accurate description of visual effect of colored moire pattern caused by layered optical structures consisting of gratings and Fresnel lens is proposed in this work. The colored moire arising from the periodic and quasi-periodic structures is numerically simulated and experimentally verified. It is found that the visibility of moire pattern generated by refractive optical elements is related to not only the spatial structures of gratings but also the viewing angles. To effectively control the moire visibility, two constituting gratings are slightly separated. Such scheme is proved to be effective to globally eliminate moire pattern for displays containing refractive optical films with quasi-periodic structures.

In this paper, an augmentation strategy is designed for the steady-state error caused by the coupling between ballistic and attitude. It can process and transform a class of nonlinear systems. Based on this, a slip form controller is designed. In the design process of the controller, a sliding surface that can be damped is calculated, and precise control of the system is realized. Then it is applied to the attitude control of the reentry vehicle, which effectively solves the problem of attitude angle control accuracy caused by the coupling between the ballistic and the attitude.

In order to enhance the robustness of reentry vehicles and improve the security of its control system, a general robustness enhancement strategy based on variable structure control is designed in this paper. Improve super-twist sliding mode reaching law, design a new type fast super-twist sliding mode reaching law. Combining strategies and methods can make robust improvements to existing control methods, thereby avoiding the need to redesign the controller.

Importance: The US is currently an epicenter of the coronavirus disease 2019 (COVID-19) pandemic, yet few national data are available on patient characteristics, treatment, and outcomes of critical illness from COVID-19. Objectives: To assess factors associated with death and to examine interhospital variation in treatment and outcomes for patients with COVID-19. Design, Setting, and Participants: This multicenter cohort study assessed 2215 adults with laboratory-confirmed COVID-19 who were admitted to intensive care units (ICUs) at 65 hospitals across the US from March 4 to April 4, 2020. Exposures: Patient-level data, including demographics, comorbidities, and organ dysfunction, and hospital characteristics, including number of ICU beds. Main Outcomes and Measures: The primary outcome was 28-day in-hospital mortality. Multilevel logistic regression was used to evaluate factors associated with death and to examine interhospital variation in treatment and outcomes. Results: A total of 2215 patients (mean [SD] age, 60.5 [14.5] years; 1436 [64.8%] male; 1738 [78.5%] with at least 1 chronic comorbidity) were included in the study. At 28 days after ICU admission, 784 patients (35.4%) had died, 824 (37.2%) were discharged, and 607 (27.4%) remained hospitalized. At the end of study follow-up (median, 16 days; interquartile range, 8-28 days), 875 patients (39.5%) had died, 1203 (54.3%) were discharged, and 137 (6.2%) remained hospitalized. Factors independently associated with death included older age (≥80 vs

The visual effect in a directional backlight auto-stereoscopic display is analyzed with Monte Carlo ray-tracing technique. The effect of microstructures on the luminescence uniformity on a liquid crystal screen is simulated and experimentally investigated. Linear Fresnel focusing lens deviating from the ideal case is studied specifically as an image focusing element.

Objectives To estimate the incidence, risk factors, and outcomes associated with in-hospital cardiac arrest and cardiopulmonary resuscitation in critically ill adults with coronavirus disease 2019 (covid-19). Design Multicenter cohort study. Setting Intensive care units at 68 geographically diverse hospitals across the United States. Participants Critically ill adults (age ≥18 years) with laboratory confirmed covid-19. Main outcome measures In-hospital cardiac arrest within 14 days of admission to an intensive care unit and in-hospital mortality. Results Among 5019 critically ill patients with covid-19, 14.0% (701/5019) had in-hospital cardiac arrest, 57.1% (400/701) of whom received cardiopulmonary resuscitation. Patients who had in-hospital cardiac arrest were older (mean age 63 (standard deviation 14) v 60 (15) years), had more comorbidities, and were more likely to be admitted to a hospital with a smaller number of intensive care unit beds compared with those who did not have in-hospital cardiac arrest. Patients who received cardiopulmonary resuscitation were younger than those who did not (mean age 61 (standard deviation 14) v 67 (14) years). The most common rhythms at the time of cardiopulmonary resuscitation were pulseless electrical activity (49.8%, 199/400) and asystole (23.8%, 95/400). 48 of the 400 patients (12.0%) who received cardiopulmonary resuscitation survived to hospital discharge, and only 7.0% (28/400) survived to hospital discharge with normal or mildly impaired neurological status. Survival to hospital discharge differed by age, with 21.2% (11/52) of patients younger than 45 years surviving compared with 2.9% (1/34) of those aged 80 or older. Conclusions Cardiac arrest is common in critically ill patients with covid-19 and is associated with poor survival, particularly among older patients.

Predicting the heat generation and dissipation characteristics accurately is vital for the lithium-ion battery management system applied in electric vehicles. To achieve such goal, an electro-thermal coupling model is established by measuring the key parameters including the open circuit voltage, entropy coefficient and internal resistance. The internal resistance is further measured by three different methods, namely the constant-current discharge (V–I) method, the difference between the OCV and the cell voltage (OCV–V) method, and the voltage drop during the 30 s intermittent discharge (HPPC) method, which is used as the input of electro-thermal coupling model. The comparatively analysis between the output results from modeling and the testing results of lithium-ion battery, such as discharge curve, temperature distribution diagram and discharged temperature rise curves, shows that HPPC method is the best internal resistance acquisition method as compared with the others.

An ultra HD, low crosstalk, high luminance uniformity, and wide field of view auto-stereoscopic display is demonstrated with the use of novel free-form surface backlight array (FFSBA) and mix-teeth Fresnel lens (MTFL) technology, in conjunction with a hybrid spatial and temporal control scenario. The luminance uniformity is shown to be higher than 95.3% even within a wide viewing angle, and the minimum achievable crosstalk can be as small as 2.2%. The moire pattern is avoided by an equivalent anisotropic film (EAF).

The FAD3000/50 safety valve is researched that is newly developed by Zhengzhou Coal Mining Machinery Group Co.,Ltd with high water-based pressure ultra great current capacity. The mathematical model is fistly established according to the study of its structure and the practical system on hydraulic support. The simulation computation has carried under the MATLAB software, and this simulation model has confirmed through the test result. After a comparison of multiple sets of simulation results, the influence of primary structure parameter’s change in safety valve to dynamic characteristics is gived.

a b s t r a c t The structure and properties of public transportation networks have great implications for urban planning, public policies and infectious disease control. We contribute a complex weighted network analysis of travel routes on the Singapore rail and bus transportation systems. We study the two networks using both topological and dynamical analyses. Our results provide additional evidence that a dynamical study adds to the information gained by traditional topological analysis, providing a richer view of complex weighted networks. For example, while initial topological measures showed that the rail network is almost fully connected, dynamical measures highlighted hub nodes that experience disproportionately large traffic. The dynamical assortativity of the bus networks also differed from its topological counterpart. In addition, inspection of the weighted eigenvector centralities highlighted a significant difference in traffic flows for both networks during weekdays and weekends, suggesting the importance of adding a temporal perspective missing from many previous studies.

According to the shearing force character and the deformation coordination condition of shell at the station of supports, the mathematical models to calculate contact angle and contact pressure distribution between tyre and shell were set up, the formulae of bending moment and bending stress of tyre were obtained. Taking the maximum of tyre fatigue life as the optimal objective, the optimization model of tyre support angle was built. The computational results show that when tyre support angle is 30°, tyre life is far less than that when tyre support angle is optimal, which is 35.6°, and it is unsuitable to stipulate tyre support angle to be 30° in traditional design. The larger the load, the less the nominal stress amplitude increment of tyre, the more favorable the tyre fatigue life when tyre support angle is optimal.

Based on the measurement of soil CO2 evolution with the Li-8150 from June 2009 to June 2010, the characteristics of soil CO2 flux from the Stipa baicalensis meadow steppe in the Hulunbeir, Inner Mongolia were analyzed. The daily dynamics of soil respiration rate in this study area presented a peak curve in growing season, the daily maximum value appeared in 13:00-15:00 p. m., while the minimum value appeared in 5:00-6:00 a. m. The soil respiration had obviously seasonal dynamics, similar with the dynamics of soil temperature and soil water content. The relationships of soil respiration with soil temperature and soil water content could be better expressed with linear or exponential-power equation. Using the Van' t Hoff exponential equation to fit soil respiration and soil temperature, the results showed that they all had good exponential regression relationships in growing season and in non-growing season. Q10 was slightly different at different depths, varying from 1.68 to 2.14 in growing season and from 3.03 to 3.60 in non-growing season. The effect of soil temperature on soil respiration was more sensitive in non-growing season than in growing season. There was significant a correlation between soil respiration and soil water content at the depth of 10 cm. The annual soil CO2 fluxes were 488.47 g C x a(-1) and 507.20 g C x a(-1) in 2009 and 2010, respectively. The contribution of soil respiration in growing season to the annual soil CO2 flux was about 90%.