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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

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.

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.

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 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.

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.

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.

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}.

In the study, the optimal experimental conditions for gypsum crystals formation were 323 K, 300 rpm stirring speed. The major impurities of Mg2+, Al3+ and Fe3+ were found to inhibit calcium sulfate crystals formation. Fe3+ caused the strongest inhibition, followed by Mg2+ and Al3+. The influence of desulfurization additives on the gypsum crystals formation was explored with the properties of moisture content, particle size distribution and crystal morphology. The organic desulfurization additives of adipic acid, citric acid, sodium citrate and benzoic acid were investigated. Citric acid and sodium citrate were found to improve the quality of gypsum. Moisture contents were reduced by more than 50%, gypsum particle sizes were respectively enlarged by 9.1 and 22.8%, induction time extended from 4.3 (blank) to 5.3 and 7.8 min, and crystal morphology trended to be thicker.

Hybrid power system which consists of a proton exchange membrane fuel cell and a battery has great perspective for Unmanned Underwater Vehicles (UUVs). As fuel cell’s working point has a direct relationship with its efficiency and lifetime, a key concern of the hybrid power system is the power distribution between the two parts. Aiming at minimizing the equivalent hydrogen cost, this work presents an optimal real-time energy management strategy based on the Pontryagin’s minimum principle. Compared with some other methods, this method possesses shorter calculation time and smaller storing space, which is helpful for online optimization in actual applications. In this research, a typical UUV working profile is tested with different initial co-state values to evaluate the proposed method, and the results indicate good robustness and effectiveness.

Accurately estimating the state of charge (SOC) of lithium-ion is very important to improving the dynamic performance and energy utilization efficiency. In order to reduce the influence of model parameters and system coloured noise on SOC estimation accuracy, this paper proposes the SOC estimation based on online identification. Based on the mixed simplified electrochemical model, the forgetting factor recursive least squares (FFRLS) method was used to identify the parameters online, and the SOC estimation was carried out in combination with Unscented Kalman Filter (UKF). Finally, the accuracy and feasibility of the method are verified by Federal Urban Driving Schedule (FUDS), the online identification and SOC estimation are carried out. The experimental results show that the SOC estimation of online parameter identification is more accurate, the system stability is faster and the error is smaller.

A process for simultaneous desulfurization and denitrification was proposed, which was made up of ozone as the oxidizing agent for NO and ammonia solution as absorbent. The results showed that the presence of SO2 and the concentration changes of NO and SO2 have little impact on the oxidation of NO, the oxidation efficiency of NO can achieve over 90% when the molar ratio of O3/NO is 1.0. The presence of NOx had little effects on the absorption of SO2, an appropriate increase of SO2 concentration was favorable to the NOx absorption. The removal efficiency of SO2 and NOx reached 99.34% and 90.01% at pH 10, flow rate 0.95 Nm3/h, n[O3]/n[NO] 1.0, initial SO2 concentration 2000 mg/Nm3, initial NO concentration 200 mg/Nm3, ammonia concentration 0.3%, oxygen content of the simulated flue gas 12%, oxidation reaction temperature 423K and absorption reaction temperature 298K in the experimental system.