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Abstract Acute gastrointestinal injury (AGI) is common in mechanically ventilated (MV) patients, but the potential association between ventilatory pressure parameters and AGI grade and their impact on mortality remains unclear. This study aimed to explore the association between ventilatory pressure parameters and AGI grade, and their interaction on all-cause mortality in MV patients. This study was a secondary analysis of a multicenter, prospective, observational study that enrolled adult patients with an expected duration of mechanical ventilation ≥ 48 h from 14 general intensive care units in Zhejiang Province between March and August 2014. The AGI grade was assessed daily on the basis of gastrointestinal symptoms, intra-abdominal pressures, and feeding intolerance in the first week of admission to the ICU. This study included 331 patients (69.2% men; mean age, 64.6 ± 18.9 years). Multivariate regression analysis showed that plateau pressure (Pplat) (OR 1.044, 95% CI 1.009–1.081, P = 0.013), serum creatinine (OR 1.003, 95% CI 1.001–1.006, P = 0.042) and APACHE II score (OR 1.035, 95% CI 1.021–1.072, P = 0.045) were independently associated with global AGI grade III/IV within 7 days of ICU admission. Moreover, global AGI grade (HR 2.228, 95% CI 1.561–3.182, P

Objective In order to solve the TBS (torsion bar shaft) torsional stiffness and strength for the outer support anti-rolling device in railway vehicles, an analytical method of introducing the TBS deformation coordination conditions is proposed. Method Taking 1/2 TBS for the outer support anti-rolling device as an example, based on its stress state and load distribution, the structural symmetry and the characteristics of bearing anti-symmetric working loads are used to introduce structural deformation coordination conditions for solving the unknown forces and moments of a primary statically indeterminate system, obtaining the shear force and bending moment distribution of the TBS, and deriving calculation formulas for the torsional stiffness and strength of the anti-rolling torsion bar device. Using the outer support anti-rolling torsion bar device made of 52CrMoV4 spring steel as an example, a comparative analysis is conducted between the analytical solution calculation results and the finite element model calculation results of the outer support TBS. Result & Conclusion The proposed analytical solution method can conveniently determine the stress levels and stress states at different TBS cross-sectional positions, providing a theoretical basis for determining the TBS cross-sectional geometric parameters, the equivalent stress calculation method of different critical cross-sections, and the analysis of TBS fatigue failure mechanism. Compared with the finite element method, the proposed analytical method features simple calculation principle and fast calculation speed.

In this study, 12 phenolic acids were theoretically calculated using the M06-2X functional. To explain their antioxidant and solvation effects, bond dissociation enthalpy (BDE), ionization potential (IP), proton dissociation enthalpy (PDE), proton affinity (PA) and electron transfer enthalpy (ETE) were calculated for each phenolic acid in the gas phase and solvents. The results showed that the BDE of gentianic acid (C5) in the gas phase was the lowest. In terms of BDE, caffeic acid (C6) had the strongest antioxidant effect in benzene, gentianic acid (C5) in acetone, and 3,4-dihydroxybenzyl alcohol (C2) in ethanol and water. In terms of IP, resveratrol had the best antioxidant activity in 4 solvents and in the gas phase. The antioxidant mechanism of phenolic acids was mainly related to hydrogen atom transfer (HAT). It was found that the ability of dehydrogenated anions and cations of phenolic acids to generate dehydrogenated free radicals was consistent with the influence of solvent polarity on IP, BDE, PDE, PA and ETE. In general, the antioxidant capacity of phenolic acids was the strongest in the weakly polar solvent acetone, followed by the strongly polar solvents water and ethanol, and phenolic acids had the weakest antioxidant capacity in non-polar solvents.

Traditional Chinese medicine (TCM) syndrome differentiation, as the core of the traditional Chinese medical system, has played an indispensable role in guaranteeing the health of the Chinese nation for thousands of years. Recently, with the collaborative promotion of multiple departments, the TCM technology innovation capability of China has been continuously enhanced. The integration of TCM syndrome differentiation with artificial intelligence AI, big data, and other fields has made new progress. Engineering frontier methods and technologies have provided an effective route for breaking through the theoretical bottlenecks of TCM syndrome differentiation. Against the backdrop of the modernization and intelligent development of TCM diagnosis in the new era, this study summarizes the fundamental theories, basic processes, and key technical links of AI-assisted TCM syndrome differentiation. The key technical links include multimodal data fusion, symptom correlation analysis, syndrome quantification, syndrome reasoning, and large-scale TCM models. It also expounds on the research ideas and development status of each link and summarizes the challenges faced by AI-assisted TCM syndrome differentiation. For instance, publicly available data are insufficient and have a poor quality; syndrome differentiation models are inadequate, have poor universality, and lack interpretability and consistency; and the evaluation of syndrome differentiation model results is limited and lack credibility. Therefore, the following suggestions are proposed for reference: (1) strengthening data integration and quality control; (2) deeply integrating AI with TCM syndrome differentiation to enhance model interpretability; (3) developing large language models for the subdivisions of TCM; (4) strengthening the construction of intelligent TCM talent teams and encouraging cooperation among experts in multiple fields; and (5) improving international standards and regulations to strengthen international cooperation and exchanges. These efforts aim to provide references for the technological exploration and innovation of AI-assisted TCM diagnosis and treatment.

Fast scanning speed and low-power consumption are becoming progressively more and more important in realizing high-performance chiplet optical phased arrays (OPAs). Here, we successfully demonstrated integrated OPAs with multiple waveguides channels based on thin-film lithium niobate-on-insulator (LNOI) platform. Specifically, two lithium niobate (LN) OPA chips have been implemented with 32 and 48 channels LN waveguides, respectively, enabled by electro-optic modulations, which showcases the low power consumption (1.11 nJ/π) and fast operation speed (14.4 ns), showing obvious advantage of the LNOI platform over others. As results, we experimentally achieved a beam steering with a 62.2° × 8.8° field of view (FOV) and a beam divergence of 2.4° × 1.2° for 32 channels, and a FOV of 40° × 8.8° and a beam divergence of 0.33° × 1.8° for 48 channels. This work also demonstrates the feasibility of LNOI platform in scalable OPA chips.

With the sustained growth of renewable energy, the flexibility of the power system has emerged as a critical indicator, influenced by frequent peak regulation. However, a dilemma exists between maximizing flexibility and optimizing economy, and a multi-objective optimization can serve as means of coordinating conflicts. In this study, condensing cogeneration units equipped with a molten salt heat storage system is research object, an optimization model for day-ahead scheduling is established, with flexibility and economy as the primary optimization objectives. To account for various constraint condition such as unit ramp rate, unit output and thermoelectric coupling properties, an enhanced version of the non-dominated sorting genetic algorithm-Ⅱ (NSGA-Ⅱ) is proposed to efficiently solve the optimization problem of a molten salt heat storage system. Flexibility and economy are used to compare and analyze the non dominated solution set obtained from the Pareto front. At the same time, the heat storage and release characteristics of a molten salt heat storage system are analyzed. The findings reveal that a focus on flexibility necessitates great motten salt heat storage to manage insufficient heating during low-load operations. Conversely, an emphasis on economy leads to frequent adjustments in heat storage to maintain optimal unit performance.

The electro-dynamic braking capacity of hydrogen-powered autonomous-rail rapid tram is severely limited by the state of charge (SOC) of the energy storage battery and the operational status of the hydrogen fuel cell. When the energy storage battery is near its full charge state and the hydrogen fuel cell continues to generate power, the storage battery is unable to store the electrical energy generated from electro-dynamic braking, leading to the failure of the electro-dynamic braking function. To maximize the electro-dynamic braking capacity of hydrogen-powered autonomous-rail rapid trams, this paper proposes an electro-dynamic braking control strategy based on pedal deceleration demand. It firstly calculates the total vehicle electro-dynamic braking force based on brake pedal stroke and load status. It then combines the current energy status of the storage system and the hydrogen fuel cell system to initiate a brake torque request to the traction system. It also calculates the electro-dynamic braking force corresponding to the deceleration required by the brake pedal stroke, optimizing the output of electro-dynamic braking force under different load, intermediate gear placement, and medium-low speed conditions. The test results show that with this electro-dynamic braking control strategy, the train fully exploits its electro-dynamic braking capacity under medium-low gear placement and medium-low speed working conditions in AW0 circumstances. It meets the design requirements for regenerative braking energy recovery of hydrogen-powered autonomous-rail rapid tram under the current electro-dynamic braking system architecture.

Objective: To develop pigmented rice lactic acid beverage with good antioxidant and hypoglycemic activity. Methods: Taking black and purple rice as the main material, the effect of mass ratio of purple rice to black rice, the addition amount of Lactobacillus bacteria, fermentation time and solid-liquid ratio on the sensory evaluation value, total phenolics content, ferric ion reducing antioxidant power （FRAP）, ABTS free radical scavenging ability, and the inhibition rate of α-glucosidase of pigmented rice lactic acid beverage were explored. Results: The optimal technology of pigmented rice lactic acid beverage was as follows: the mass ratio of purple rice to black rice was 1∶5, the solid-liquid ratio was 1∶8 （g/mL）, the addition amount of lactic acid bacteria was 5%, and the fermentation time was 40 h. Under these conditions, the sensory score of pigmented rice lactic acid beverage was 83.6±2.51, ABTS radical scavenging capacity was （145.02±7.88） mmol TE/g·DW, FRAP was （33.41±1.70） mmol Fe2+/g·DW, total phenolics were （4 208.78±281.26） μg GAE/g·DW, α-glucosidase inhibitory rate activity was （13.94±0.01）%. Conclusion: The pigmented rice lactic acid beverage possessed purplish red color, soft in taste, moderate in sour and sweet taste, with good antioxidant activity and α-glucosidase inhibition effect.

Two-pole structures refer to the fact that two dynamically generated states are located close to each other between two coupled channels and have a mass difference smaller than the sum of their widths. Thus, the two poles overlap in the invariant mass distribution of their decay products, creating the impression that only one state exists. This phenomenon was first noticed for the Λ(1405) and the K1(1270), and then for several other states. This report explicitly shows how the two-pole structures emerge from the underlying universal chiral dynamics describing the coupled-channel interactions between a heavy matter particle and a pseudo-Nambu-Goldstone boson. Furthermore, we predict similar two-pole structures in other systems dictated by chiral symmetry, such as the isospin 1/2 K¯∑c − πΞ′c coupled channel, awaiting experimental discoveries.

The integration of underwater detection and communication uses communication signals to detect a target actively, but the Doppler effect deteriorates the parameter estimation performance of the integrated system. To eliminate the influence of the Doppler effect, a joint Doppler estimation and compensation method based on spectrum zooming and correction is proposed. Firstly, the synchronization signal is used to obtain the signal receiving delay and intercept the single-frequency signal segment in the received signal. Then, the discrete Fourier transform is used to find the frequency that corresponds to the maximum amplitude of the single-frequency signal segment. Finally, the frequency spectrum is refined and corrected within the range near the frequency. The Doppler factor is estimated and the received signal is compensated by the Doppler estimation value. The simulation results show that the proposed method improves Doppler factor estimation accuracy, increases the cross-correlation processing gain and improves DOA (direction of arrival) estimation performance, thus being robust to different Doppler effects.

The aim of this work was to investigate the volatile compositions of four Chinese functional liquors. For this purpose, volatile compounds of four liquors were extracted with head-space solid-phase microextraction (HS-SPME) and analyzed with gas chromatography-mass spectrometry (GC-MS) along with the determination of odor activity value (OAV) and relative odor contribution (ROC). Sixty volatiles were tentatively identified and categorized into the following seven groups: alcohols, esters, fatty acids, carbonyl compound, hydrocarbons, phenols, and other components. The differences in chemical composition of volatile compounds were visualized with heat maps. Odorants were compared with different samples using a statistical analysis of Venn diagrams and a multivariate principal component analysis, and ethyl hexanoate, ethyl acetate, and ethyl octanoate were found to be the key odorants. Besides, abundant phenolic contents and high antioxidant ability of four Chinese functional liquors could potentially bring better health-boosting effects.

The land–sea–air–space integrated information network is capable of providing globally accessible, safe, and reliable information services for land-, sea-, space-, and air-based users; it is an important infrastructure for China to maintain independence in the field and to become a cyberpower. This study uses literature research and expert consultation as the main research methods to summarize the development requirements of the land–sea–air–space integrated information network. After a detailed study on typical domestic and foreign systems, the major weaknesses of China’s land–sea–air–space integrated information network are summarized. Moreover, an integrated information network architecture and development routes are proposed. Specifically, we suggest that China should focus on the deep integration in terms of network architecture, technical system, and application services; integrate the communication, navigation, and remote sensing systems; promote technical independence and industrial upgrade of space-based networks; and strengthen its system security protection capabilities.

WSN (Wireless Sensor Network) is an important way to transmit intelligent electricity business data, but it is more and more difficult to meet different performance requirements of different businesses. In the view of WSN power control problem, an adaptive power control algorithm based on intelligent electricity business classification was proposed in this paper. Firstly, the theory of node power control was analyzed. Secondly, the business classification and interference power adjustment factors were increased, to combine intelligent electricity business with network topology of WSN and realize the modeling of business classification based adaptive power control algorithm. Finally, this algorithm was compared with optimal power algorithm and LINT algorithm by simulation experiment in the performance of packet loss rate, delay and throughput. Simulation results showed that the algorithm proposed in this paper is better than others.

Objective To investigate the relation between vasculogenic mimicry (VM) and MIG-7 in osteosarcoma, as well as their roles in the prognosis, and to establish a model for predicting the prognosis of osteosarcoma. Methods VM was identified by CD31/PAS double-staining in 156 cases of AJCC stage Ⅱ extremity osteosarcoma. Tumor samples were also immunohistochemically stained for MIG-7 to determine whether it was associated with the occurrence of VM. Univariate and multivariate Cox regression analyses were used to identify prognostic factors and a prognostic nomogram for predicting 3- and 5-year OS and MFS was constructed. C-index and calibration curves were used to verify the predictive accuracy of the model. Results The MIG-7 expression in osteosarcoma tissues was associated with VM formation, but MIG-7 expression was not associated with gender, age, AJCCⅡA/ⅡB stage, tumor location, surgical type or histological response to pre-operative chemotherapy. Survival analysis showed that MIG-7 expression, VM and pre-operative chemotherapy were identified as three independent prognostic factors. The value of C-index in nomogram was greater than 0.7. The predicted calibration curve was similar to the standard curve. Conclusion MIG-7 accelerates the progression of osteosarcoma by promoting VM formation, and may also affect prognosis through other mechanisms. The nomogram could afford accurate prognosis prediction and individualized diagnosis and treatment for osteosarcoma patients.

With the rapid development of the Internet, each platform often uses metadata to organize and manage system data resources. The system within the platform is closed so that metadata resources are dispersed and stored repeatedly, which increases the difficulty of metadata sharing and reduces the utilization of metadata. In order to solve this problem, this paper proposes a public metadata configuration management platform, which provides unified configuration and management of public metadata, provides configuration and shared metadata services by using Web Service technology, and improves data sharing efficiency by using Redis memory database. At present, a configuration management platform based on meteorological public metadata has been used in the meteorological big data platform, which not only improves the utilization of the platform common metadata, saves storage, but also improves the response speed of the service. This article abstracts the main functions of the configuration management platform, making the system design applicable to other similar metadata-based data sharing platforms.

This paper investigates the influence of carrier gas flow on the external flow field of coaxial powder feeding nozzle. FLUENT software was adopted to establish gas-solid two-phase flow. The simulation of powder stream field under different carrier gas flow was also carried out. Results show that the larger the flow of carrier gas is, the higher the gas flow field velocity at the nozzle outlet is. At the same time, the concentration at the convergence point is lower, and the convergent point is maintained at 0.015 m. Under the condition of 4 L/min, the powder flow convergence is good. When it exceeds 4 L/min, powder spot diameter increases. The experiment of powder aggregation and laser cladding forming were completed, which shows that the forming effect is the best one under the condition of 4 L/min. It is consistent with the simulation analysis results and has a high reference to the optimization of the process parameters of coaxial nozzle.

A theoretical model of a vibrating electret electrostatic energy harvester for a double-ended fixed beam was established herein for a low-frequency vibration energy in the environment. The key parameters of the electrostatic energy harvester were optimized by a MATLAB/Simulink numerical analysis. The relationship between the output power, resonant frequency, and half-power bandwidth and the electret surface potential, air gap, and load resistance was also studied. The magnitude of the external excitation acceleration and the size of the electret remained constant. The numerical results are as follows:(1) the existence of an optimal surface potential makes the output power of the electrostatic energy harvester reach the maximum value. The soft spring effect gradually increases with the increase of the surface potential, making the resonant frequency of the energy harvester device shift. The bandwidth also gradually increases. (2) An optimal initial air gap maximizes the power when the surface potential is constant. The half-power bandwidth decreases as the gap increases. (3) An optimal load maximizes the power when the surface potential and the air gap remains constant. The resonant frequency is offset as the load decreases. (4) An optimal load is used to maximize the half-power bandwidth when the air gap is constant. The larger the surface potential, the greater the half-power bandwidth under the same load. Experiments show that the output characteristics of the energy harvester under different load resistances have the following characteristics:with the increase of the load resistance, the output power and the half-power bandwidth increase at the beginning, then decrease. The maximum output power is 0.188 mW when the load resistance is 90 MΩ. In addition, the half-power bandwidth reaches the maximum value of 4.7 Hz when the load resistance is 330 MΩ.

Taking the dual clutch transmission as analysis object,a three-state dynamics model is built.The theoretical expressions of the shifting jerk of each states during the shifting process also are deduced. Considering the circulating power and the order of the operations of two clutches,the effects of above two factors on the shift jerk during the shifting process is analyzed detailedly. A control strategy of clutches basing on the speed adjustment of engine for dual clutch transmission is proposed. After that,a simulation model is built based on Matlab/Simulink platform. The result of the simulation shows that the control strategy coming from the theory can reduce the shift jerk effectively.

The effects of limestone, Cl-, Fe3+ and Mn2+ in slurry on the characteristics of calcium sulfate dehydrate (DH) in flue gas desulfurization (FGD) process were investigated. The moisture content, particle size distribution, and crystal morphology were considered as end use characteristics of DH. As a result, the number of needle-like DH crystals was increased with increasing total contents of MgCO3, Al2O3 and Fe2O3 in limestone. Cl ions were reported to distort the crystal structure and change the crystals from orthorhombic to irregular. Mn2+ can increase the desulfurization efficiency by catalyzing the oxidation of SO2. Finally, Fe3+ will inhibit crystal growth of all faces, except {011} and {111}.