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Grain boundary serration and its effect on creep property in LPBF-built Inconel 718 alloy was investigated systematically. By considering the variation of the wavelength and amplitude with processing parameters, this study elucidates the evolution of the serration degree with changes in the intermediate solution treatment and cooling rate. A processing map for the serrated grain boundaries is presented. Three distinct formation mechanisms arise which rely upon grain boundary interaction with δ phase and element segregation: (i) specific direction of δ phase growth induced serration, (ii) the pinning of separated δ phase which hinders the grain boundaries movement, and (iii) lattice distortion resulting from element segregation induced serration. The creep tests under 650 °C/750 N have been performed on samples with different microstructure, one featuring non-serrated and the other with serrated grain boundaries, while keeping other aspects of the microstructure invariant. Compared to non-serrated grain boundary samples, the creep life of serrated grain boundary samples is increased by 56%, the creep strain is increased by 19%, and creep strain rate is decreased by 26%. Grain boundary serration can improve both creep life and creep ductility. The failure modes and accumulated damage were performed using SEM and EBSD technique. It can be found that serrated grain boundaries play a more crucial role in delaying cracks initiation due to it can alleviate the intensity of stress concentration.

Abstract With the rapid development of renewable energy, photovoltaic energy storage systems (PV-ESS) play an important role in improving energy efficiency, ensuring grid stability and promoting energy transition. As an important part of the micro-grid system, the energy storage system can realize the stable operation of the micro-grid system through the design optimization and scheduling optimization of the photovoltaic energy storage system. The structure and characteristics of photovoltaic energy storage system are summarized. From the perspective of photovoltaic energy storage system, the optimization objectives and constraints are discussed, and the current main optimization algorithms for energy storage systems are compared and evaluated. The challenges and future development of energy storage systems are briefly described, and the research results of energy storage system optimization methods are summarized. This paper summarizes the application of swarm intelligence optimization algorithm in photovoltaic energy storage systems, including algorithm principles, optimization goals, practical application cases, challenges and future development directions, providing new ideas for better promotion and application of new energy photovoltaic energy storage systems and valuable reference.

Reaction characteristics in pyrometallurgical treatment for aluminum dross were studied qualitatively and quantitatively by thermal analysis. The transformation of aluminum nitride (AlN), volatilization of chlorides and fluorides in two kinds of dross under both argon (Ar) and Ar-Oxygen (O2) atmospheres were in detail analyzed and compared. Gas species including water vapor (H2O(g)), ammonia (NH3), nitrogen (N2), nitric oxide (NO), and carbon dioxide (CO2) were clearly identified. The study indicated that N2 and small amount of NO were produced from AlN–O2 reaction while NH3 from AlN–H2O(g) reaction, and H2O(g) and CO2 were necessarily from thermal decomposition of hydroxides and carbonates. Calculation indicated that the AlN–O2 reaction, AlN–H2O(g) reaction, and volatilization of chlorides or fluorides were remarkably slow, for around 30 mg raw material with taking about 37 min to finish the AlN–O2 reaction in 500–1000°C, 60 min to the AlN–H2O(g) reaction in 130–500 °C, and 30 min to the volatilization of chlorides or fluorides in 760–1000°C. Kinetics study indicated that the Ginstling-Brounshtein's diffusion model and Jander's diffusion model were most appropriate for describing the kinetics, respectively with an apparent activation energy of 273.2 kJ mol−1 and 307.4 kJ mol−1 for the AlN–O2 reaction, and with that of 182.0 kJ mol−1 and 194.0 kJ mol−1 for AlN–H2O(g) reaction. The study will be beneficial for design, optimization of pyrometallurgical routes of aluminum dross treatment and for evaluating its environmental effect.

Objective This case–control study tested a crisis awareness-based chain warning management model for patients with difficulties cooperating with magnetic resonance imaging (MRI) examinations. Methods All participants experienced difficulties cooperating with MRI examinations and underwent cranial magnetic resonance spectroscopy (MRS) and MRI at the same hospital in China. The control group (n = 1233) underwent examinations from January to June 2023 and received routine nursing care (pre-examination safety notification, instructions on cooperating during the examination, post-examination observation). A crisis awareness chain warning management model was implemented for the intervention group (n = 1352), who underwent examinations from July to December 2023. The groups were compared on average time for examination completion, quality of care and occurrence of complications. Data were collected using a self-devised data collection form. Results The average length of time to complete MRS and MRI was shorter for intervention group patients than for control group patients. The intervention group showed better pre-examination preparation, examination success rate, image quality attainment rate, and one-time examination success rate, and lower incidence of examination-related complications. Conclusion This management model could increase MRI examination efficiency, improve quality of care, reduce complications and increase nurses’ understanding of nursing continuity and crisis awareness.

Microwave heating has the characteristics of simple control and high efficiency, in which electromagnetic force plays an important role. Using the UDF function and energy equation in FLUENT software, the electromagnetic force model in the tube is established. The mixing process of cerium chloride solution under different heating modes, the mixing effect of Lorentz force and the preparation process of cerium oxide under different inlet material velocities were numerically simulated. CFD-Post and MATLAB software are used to post-process the data of the whole fluid area. Through the above analysis, the best process conditions of numerical simulation and experiment are finally determined. The results show that microwave heating has better mixing effect and lower material loss compared with conventional heating, in which electromagnetic force plays a promoting role; Under the condition of microwave heating, the product conversion rate is high, and the concentration of cerium oxide is high and distributed evenly. The more appropriate mixing method of cerium chloride and preparation method of cerium oxide are microwave heating, and the more appropriate inlet velocity of materials is 0.15 m/s.

Persistent organic pollutants seriously affect the growth and development of crops. 1,2,4-Trichlorobenzene (TCB), as one of the most widely used chlorobenzenes, can affect the yield of japonica rice. However, existing research on the effect of TCB on japonica rice yield is not in-depth, and a basic understanding of commonality has not yet been formed. In this study, 28 conventional japonica rice varieties were selected to investigate the effects of TCB stress on their yield, yield composition, and TCB accumulation. This study also evaluated the efficiency of conventional tolerance indices in evaluating the TCB stress tolerance of japonica rice. The results showed that TCB caused sustained inhibition of the growth of japonica rice, which was considerably manifested in plant height, root length, soil plant analysis development (SPAD), and dry weight at different growth stages. Under TCB stress, TCB accumulation in various tissues of japonica rice increased sharply. TCB stress reduces the yield of japonica rice by reducing the number of panicles per hill, the number of spikelets per panicle, the grain filling percentage, and the grain weight. Overall, the results of this study indicate that TCB stress can cause a decrease in the yield of japonica rice, and the decrease in panicle number is the main reason. The conventional tolerance index can effectively evaluate the tolerance of japonica rice to TCB. The results of this study are substantial for the breeding and cultivation of japonica rice.

The separator is one of the core inner components of the lithium-ion battery, and its performance directly affects the electrochemical properties, life, and safety performance of the battery. In this research, the physical and electrochemical properties of polyethylene (PE), polypropylene (PP) / PE/PP multilayer, (PP), and aluminum oxide ceramic-coated PE (PE–Al2O3) separators were analyzed and compared in detail. Among the separators, the PE–Al2O3 separator exhibited better performance pertaining to puncture strength, thermal stability, wettability, and ionic conductivity. However, its tensile strength is slightly lower than that of the PP/PE/PP separator. The surface of the PE, PP, and PP/PE/PP separators exhibited a large number of submicron pores. Alumina particles were uniformly distributed on the surface of the PE–Al2O3 separator, and a large number of clear pores were presented between the alumina particles. The PP/PE/PP separator exhibited the best tensile properties among the separators in the mechanical direction; the tensile strength of the PP/PE/PP separator was 247.53 MPa, which is higher than that of the PE–Al2O3 (197.58 MPa), PP (119.06 MPa), and PE (147.69 MPa) separators. Meanwhile, the puncture strength of the PE separator was the lowest among the separators at 144.26 N·mm−1 whereas that of the PE–Al2O3 separator was the highest at 426.91 N·mm−1, which was attributed to the high hardness of alumina particles. The melting temperature of the PE–Al2O3 separator was 140.9 ℃, which is lower than that of the PP and PP/PE/PP separators but higher than that of the PE separator. Further, it exhibited no heat shrinkage with heat treatment at 140 ℃ for 1 h. Accordingly, the PE–Al2O3 separator exhibited the best thermal stability compared to the PP, PP/PE/PP, and PE separators. The unique hydrophilic properties of alumina particles improved the wettability between the separator and electrolyte; the wetting angle between the PE–Al2O3 separator and the electrolyte was 12.3°, which was considerably smaller than that for the PP (35.9°), PE (38.3°), and PP/PE/PP (35.3°) separators. The electrolyte wettability of the PE–Al2O3 separator effectively reduced the transmission resistance of lithium ions between the anode and cathode, enabling the separator to exhibit an excellent ionic conductivity (0.719 mS·cm−1). After 100 cycles at 1 C, the capacity retention rate of the PE Al2O3 separator was 91.19%, which was considerably better than the other three types of separators. To summarize, this study reveals that the PE–Al2O3 separator has the best application prospect in high power, long-term stability, and high-safety lithium-ion batteries.

Abstract Background Sensory stimulation can play a fundamental role in the activation of the primary sensorimotor cortex (S1-M1), which can promote motor learning and M1 plasticity in stroke patients. However, studies have focused mainly on investigating the influence of brain lesion profiles on the activation patterns of S1-M1 during motor tasks instead of sensory tasks. Therefore, the objective of this study is to explore the lesion-specific activation patterns due to different brain lesion profiles and types during focal vibration (FV). Methods In total 52 subacute stroke patients were recruited in this clinical experiment, including patients with basal ganglia hemorrhage/ischemia, brainstem ischemia, other subcortical ischemia, cortical ischemia, and mixed cortical–subcortical ischemia. Electroencephalograms (EEG) were recorded following a resting state lasting for 4 min and three sessions of FV. FV was applied over the muscle belly of the affected limb’s biceps for 3 min each session. Beta motor-related EEG power desynchronization overlying S1-M1 was used to indicate the activation of S1-M1, while the laterality coefficient (LC) of the activation of S1-M1 was used to assess the interhemispheric asymmetry of brain activation. Results (1) Regarding brain lesion profiles, FV could lead to the significant activation of bilateral S1-M1 in patients with basal ganglia ischemia and other subcortical ischemia. The activation of ipsilesional S1-M1 in patients with brainstem ischemia was higher than that in patients with cortical ischemia. No activation of S1-M1 was observed in patients with lesions involving cortical regions. (2) Regarding brain lesion types, FV could induce the activation of bilateral S1-M1 in patients with basal ganglia hemorrhage, which was significantly higher than that in patients with basal ganglia ischemia. Additionally, LC showed no significant correlation with the modified Barthel index (MBI) in all patients, but a positive correlation with MBI in patients with basal ganglia lesions. Conclusions These results reveal that sensory stimulation can induce lesion-specific activation patterns of S1-M1. This indicates FV could be applied in a personalized manner based on the lesion-specific activation of S1-M1 in stroke patients with different lesion profiles and types. Our study may contribute to a better understanding of the underlying mechanisms of cortical reorganization.

Pre-aging treatment before cold rolling and final aging was introduced to optimize the mechanical properties and electrical conductivity properties of Cu-0.75Fe-0.35Ti alloy. The alloy was pre-aged at 540 °C for 6 h, then cold rolled with thickness reduction of 80%, followed by aging at 460 °C for 2 h (SARA). Vickers hardness, electronic conductivity and uniaxial tensile tests were conducted to measure the mechanical and electrical conductivity properties. Electron backscatter diffraction and transmission electron microscope were used to characterize the microstructural evolution. The results showed that the hardness, tensile strength and electrical conductivity of SARA were up to 198.2 ± 4.8 HV, 622.6 ± 6.3 MPa and 63.8% IACS, respectively, which were superior to those achieved without pre-aging. The enhanced mechanical properties of SARA were attributed to an increase in low angle boundaries (LABs), geometrically necessary dislocation (GND) density and volume fraction of precipitates, while the favorable electrical conductivity was ascribed to the enhancement of precipitation and resultant matrix purification.

The aluminum dross generated during the aluminum alloy processing and regeneration process contains a large amount of harmful highly reactive aluminum nitride and salts, which can cause environmental pollution. A novel method for preparing calcium aluminate by dry calcification of aluminum dross is proposed in this paper to extract valuable aluminum resources while achieving efficient detoxification. Detection methods such as XRD, XRF, and standard dissolution procedures have been applied to characterize the phase transition and reaction behavior of the aluminum extraction process. The results indicate that calcium additives can react with aluminum components in aluminum dross to generate 12CaO·7Al2O3 (C12A7), which is soluble in sodium carbonate solution, thereby separating it from other impurities. Under the optimal roasting conditions, the leaching rate of alumina is 87.89%, and the removal rate of nitrogen, chlorine, and soluble fluorine elements exceeds 99%.Excessive sodium carbonate is required to ensure that the hydrolysis product of C12A7 is calcium carbonate, avoiding the formation of hydrated calcium aluminate precipitates. The optimal leaching conditions are sodium carbonate concentration of 80 g L−1, caustic soda concentration of 5 g L−1, liquid-solid ratio of 8 mL g−1, and leaching time of 30 min. The leaching reaction of calcium aluminate conforms to the unreacted core model controlled by internal diffusion, and the apparent activation energy of the reaction is 18.05 kJ mol−1.

Agrobacterium tumefaciens is a soil-borne pathogenic bacterium that causes crown gall disease in many plants. Chemotaxis offers A. tumefaciens the ability to find its host and establish infection. Being an aerobic bacterium, A. tumefaciens possesses one chemotaxis system with multiple potential chemoreceptors. Chemoreceptors play an important role in perceiving and responding to environmental signals. However, the studies of chemoreceptors in A. tumefaciens remain relatively restricted. Here, we characterized a cytoplasmic chemoreceptor of A. tumefaciens C58 that contains an N-terminal globin domain. The chemoreceptor was designated as Atu1027. The deletion of Atu1027 not only eliminated the aerotactic response of A. tumefaciens to atmospheric air but also resulted in a weakened chemotactic response to multiple carbon sources. Subsequent site-directed mutagenesis and phenotypic analysis showed that the conserved residue His100 in Atu1027 is essential for the globin domain’s function in both chemotaxis and aerotaxis. Furthermore, deleting Atu1027 impaired the biofilm formation and pathogenicity of A. tumefaciens. Collectively, our findings demonstrated that Atu1027 functions as an aerotaxis receptor that affects agrobacterial chemotaxis and the invasion of A. tumefaciens into its host.

Unconventional double-peak age strengthening phenomenon has occasionally been observed in some alloys, yet the underlying mechanism responsible for this phenomenon are still unclear. Here, we for the first time report the double-peak age strengthening phenomenon in the Cu–Be–Ni–Co alloys and try to unveil the underlying mechanism. Both the theoretical and experimental analyses demonstrate that the strong coherency strengthening effect of tiny nanoprecipitates (

The black aluminum dross (BAD) from aluminum recycling industry is considered to be a hazardous material due to containing a large amount of AlN and fluoride salt. The potential environmental problems caused by BAD restrict the sustainable development of the aluminum recycling industry. A calcining-leaching process for preparing α-Al2O3 by using BAD is proposed in this paper. The transformation mechanism of toxic substances is discussed in detail based on the analysis of TG-DTG-DSC&MS. The results show that the reaction between AlN and O2 occurs in the range of 500–1000 °C. Most of the gaseous products are N2, and there is also a small amount of NO. The average conversion rate is 0.087 mg/min. The average volatilization rate of chloride salt in BAD under Ar atmosphere is 0.065 mg/min, and the average volatilization rate under Ar + O2 atmosphere is 0.089 mg/min, which is slightly higher than that of pure Ar atmosphere. The BAD processed by calcination-leaching process contain more than 95 % corundum and magnesia-aluminum spinel, which can be used as high-quality raw materials for the preparation of refractory materials.

The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure–property correlations at the nanoscale. However, a serious problem for metal nanocluster catalysts is that the ligands inhibit the catalytic activity through deactivating the surface of the nanoclusters. Here, we introduce a novel catalytic mode for metal nanoclusters, in which the nanoclusters initiate the catalysis via single electron transfer (SET) without destroying the integrity of nanoclusters, providing a solution for the contradiction between activity and stability of metal nanoclusters. We illustrated that the novel activation mode featured low catalyst loading (0.01 mol %), high TOF, mild reaction conditions, and easy recycling of catalyst in alkyne hydroborylation, which often suffered from poor selectivity, low functional group tolerance, etc. Furthermore, the catalyst [Au1Cu14(TBBT)12(PPh3)6]+ (TBBTH: p-tert-butylthiophenol) can be applied in highly efficient tandem processes such as hydroborylation–deuteration and hydroborylation–isomerization, demonstrating the utility of the introduced activation mode for metal nanoclusters.

BackgroundAging is an inescapable process, but it can be slowed down, particularly facial aging. Sex and growth hormones have been shown to play an important role in the process of facial aging. We investigated this association further, using a two-sample Mendelian randomization study.MethodsWe analyzed genome-wide association study (GWAS) data from the UK Biobank database comprising facial aging data from 432,999 samples, using two-sample Mendelian randomization. In addition, single-nucleotide polymorphism (SNP) data on sex hormone-binding globulin (SHBG) and sex steroid hormones were obtained from a GWAS in the UK Biobank [SHBG, N = 189,473; total testosterone (TT), N = 230,454; bioavailable testosterone (BT), N = 188,507; and estradiol (E2), N = 2,607)]. The inverse-variance weighted (IVW) method was the major algorithm used in this study, and random-effects models were used in cases of heterogeneity. To avoid errors caused by a single algorithm, we selected MR-Egger, weighted median, and weighted mode as supplementary algorithms. Horizontal pleiotropy was detected based on the intercept in the MR-Egger regression. The leave-one-out method was used for sensitivity analysis.ResultsSHBG plays a promoting role, whereas sex steroid hormones (TT, BT, and E2) play an inhibitory role in facial aging. Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels had no significant effect on facial aging, which is inconsistent with previous findings in vitro.ConclusionRegulating the levels of SHBG, BT, TT, and E2 may be an important means to delay facial aging.

The spray pyrolysis method has the disadvantage of nozzle plugging, and the conventional heating model causes a large temperature gradient, which leads to unevenly heated reactants. This study used cerium chloride heptahydrate and Venturi reactor as raw material and core equipment. The technology of microwave heating was combined to prepare single-phase sphere-like cerium oxide. The mean size of the particles was near 80nm. The product was characterized via XRD, SEM, and EDS technologies. The purity, morphology, and energy consumption were compared with the conventional spray pyrolysis. Fluent software coupled with HFSS was employed to simulate the effects of different process conditions on products’ purity and temperature field in the reactor. There was good correspondence between experimental and simulated results. The results showed that as gas velocity Vg increased, the tendency of the temperature field distribution did not change. The lowest mass fraction of chlorine element reached 0.13% when the gas inlet velocity reached 1.7 m/s. When the material inlet velocity was 0.05 m/s, the mass fraction of the chlorine element was below 0.1%, which indicated that the reactants had a complete reaction. It has been calculated that the heating cost, energy consumption, and CO2 emission decreased sharply compared with the spray pyrolysis method.

Objectives: Acute type A aortic dissection (ATAAD) with severe stenosis or occlusion of the true lumen of aortic arch branch vessels often leads to an increased incidence of severe postsurgical neurological complications and mortality rate. In this study, we aimed to introduce our institutional extra-anatomic revascularization and cannulation strategy with improved postoperative outcomes for better management of patients with cerebral malperfusion in the setting of ATAAD. Methods: Twenty-eight patients with ATAAD complicated by severe stenosis or occlusion of the aortic arch branch vessels, as noted on combined computed tomography angiography of the aorta and craniocervical artery, between January 2021 and June 2022 were included in this study. Basic patient characteristics, surgical procedures, hospitalization stays, and early follow-up results were analyzed. Results: The median follow-up duration was 16.5 months (interquartile range: 11.5–20.5), with a 100% completion rate. The 30-day mortality rates was 7.1% (2/28 patients); two patients had multiple cerebral infarctions on preoperative computed tomography and persistent coma. Postoperative transient neurological dysfunction occurred in 10.7% (3/28) of the patients, and no new permanent neurological dysfunction occurred. Of all the patients, 3.6% (1/28) had novel acute renal failure. No other deaths, secondary surgeries, or serious complications occurred during the early follow-up period. Conclusions: Use of extra-anatomic revascularization and a new cannulation strategy before cardiopulmonary bypass is safe and feasible and may reduce the high incidence of postoperative neurological complications in patients with ATAAD and cerebral malperfusion.

Cu-Be alloys exhibit excellent comprehensive performance in electrics, thermotics, and mechanics, and hence, they attract much attention. Among them, low-Be copper alloys are more environmentally friendly and promising. This study explores the effects of different Ni contents and heat treatment parameters on the properties, microstructures, and precipitates of Cu-0.2 wt% Be-x wt% Ni (0 < x < 2.0) alloys. The experimental results demonstrate that the fast cooling rate of cast alloys during solidification contributes to retention of the solute atoms in the copper matrix, which is beneficial for subsequent solid solution treatment. Furthermore, solid solution treatment slightly reduces the electrical conductivities, microhardness values, and compressive yield strengths of Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The optimal solution temperature and time are about 925 ℃ and 60 min, respectively. Aging treatment significantly increases the electrical conductivities, microhardness values, and compressive yield strengths of Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The best aging temperature is around 450 ℃. However, the properties of Cu-0.2 wt%Be-0.4 wt%Ni alloys remain unaffected by solution and aging treatments. Around x = 1.0, Cu-0.2 wt% Be-x wt% Ni alloys possess the best comprehensive properties, which are about 72%IACS of electrical conductivity, 241 HV of microhardness, and 281MPa of compressive yield strength, respectively. TEM and EDS analyses reveal that the precipitate evolution of Cu-0.2 wt% Be-1.0 wt% Ni alloys with aging time is GP zones → γ″ → γ′. Notably, a distinct double-peak age strengthening phenomenon emerges with Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The precipitation of plenty of GP zones at the early stage of aging should account for the first strengthening peak, and the strengthening mechanism transformation of the γ″ or γ′ phase from shear to Orowan should induce the second strengthening peak. This work may help to design new low-Be copper alloys and their preparation processes.

Abstract With the advent of the 5G era, the design of electronic equipment is developing towards thinness, intelligence and multi-function, which requires higher cooling performance of the equipment. Micro-channel heat sink is promising for the heat dissipation of super-thin electronic equipment. In this study, thermal resistance theoretical model of the micro-channel heat sink was first established. Then, fabrication process of the micro-channel heat sink was introduced. Subsequently, heat transfer performance of the fabricated micro-channel heat sink was tested through the developed testing platform. Results show that the developed micro-channel heat sink has more superior heat dissipation performance over conventional metal solid heat sink and it is well suited for high power LEDs application. Moreover, the micro-channel structures in the heat sink were optimized by orthogonal test. Based on the orthogonal optimization, heat dissipation performance of the micro-channel radiator was further improved.

Elderly people usually have poorer surgical tolerance and a higher incidence of complications when undergoing revision surgery after posterior instrumented lumbar fusion (PILF). Full-endoscopic transforaminal surgery is a safe and effective option, but sometimes, it is difficult to revise L5-S1 foraminal stenosis (FS) after PILF. Therefore, we developed full-endoscopic lumbar decompression (FELD) at the arthrodesis level via a modified interlaminar approach under local anesthesia. This study aimed to describe the technical note and clinical efficacy of the technique. Eleven patients with unilateral lower limb radiculopathy after PILF underwent selective nerve root block and then underwent FELD. Magnetic resonance imaging (MRI) and computer tomography (CT) were performed on the second postoperative day. Their clinical outcomes were evaluated with a Visual analog scale (VAS) of low back pain and sciatica pain, Oswestry disability index (ODI), and the MacNab score. Complete decompression was achieved in every case with FELD without serious complications. Postoperative VAS of sciatica pain and ODI at each time point and VAS of low back pain and ODI after three months postoperatively were significantly improved compared with those preoperative (p < 0.05). According to the MacNab criteria, seven patients (63.6%) had excellent results at the two-year follow-up, and four patients (36.4%) had good results. No patients required further revision surgery. FELD, via a modified interlaminar approach, is effective for treating unilateral L5-S1 FS after PILF in elderly people.

In order to diagnose the location and severity of radial friction of centrifugal compressor set in the long-distance gas pipeline accurately, identify causes of radial friction in time, treat the radial friction quickly and properly, and guarantee the safe and stable operation of the long-distance gas pipelines, the mechanism of radial friction was studied. The vibration state of the centrifugal compressor set as a result of fraction faults, such as the local radial friction, local frictional thermal bending and all-round friction was analyzed. Meanwhile, the radial friction of centrifugal compressor set was judged and evaluated according to the abnormal vibration shown by the centrifugal compressor set. Further, it was verified by the fault cases, and the relevant solutions were proposed based on various radial friction types. Conclusively, the research results could provide basis and experience for the identification, analysis, diagnosis, troubleshooting, treatment and overhaul scheme formulation of radial friction fault of centrifugal compressor sets in the long-distance natural gas pipeline, which is helpful to ensure the stable operation of the centrifugal compressor set.

IntroductionBurns are a common trauma associated with considerable mortality and morbidity. Although a lot is known regarding burns' pathogenesis, the involvement of ferroptosis is uncertain. Here, we aimed to explore vital ferroptosis-related genes and molecules in burns, through bioinformatics analysis, to uncover new effective therapeutic targets.MethodsThe FerrDb database was used to acquire ferroptosis-related genes and GSE19743 was downloaded from Gene Expression Omnibus (GEO), a dataset with analysis of control and burned individuals. Hub genes were selected with Cytoscape software, and Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted. Cox proportional hazard function and Kaplan-Meier survival analyses were implemented to screen prognosis-related genes. Additionally, the miRWalk database was used to acquire the miRNAs relevant to our hub genes function and analyzed for enrichment.ResultWe identified 64 differentially expressed genes and through the intersection with ferroptosis-related genes, 10 were selected as hub genes. GO analysis revealed that the hub genes' most enriched activities were response to oxidative stress, pyridine-containing compound metabolic processes, and reactive oxygen species metabolic processes. KEGG pathways' analysis showed that these overlapped genes were enriched in several pathways, namely, in VEGF signaling. Furthermore, the molecular miRNA functions significantly enriched were signal transduction and cell communication, namely, the biological pathways of the glypican pathway and the ErbB receptor signaling network. SLC40A1 and GPT2 genes were found to be associated with overall survival, suggesting an important role in burn prognosis.DiscussionThis study may improve our understanding of the underlying burn mechanisms and provide a new direction for the prevention of poor outcomes, advances in burns treatment, and drug development.

PURPOSE :Bone tracers have been validated for many years in detecting transthyretin cardiac amyloidosis (TTR-CA). However, several new studies suggest conflicting results. Our study aimed to systematically evaluate the accuracy of bone radiotracers for diagnosis and differentiation of TTR-CA via a systematic review and meta-analysis.METHODS:We retrieved articles assessing the performance of bone tracer in diagnosing and differentiating TTR-CA from PubMed, the Cochrane Library, ScienceDirect, and DOAJ databases, dating up to 10 July 2020. The meta-analysis was conducted through Stata 16 software, and the risk of bias for the included studies was assessed by the QUADAS-2 tool. Moreover, we made a comprehensive review.RESULTS:Fourteen articles were included in the systematic review, and 9 in the meta-analysis. The pooled sensitivity was 0.97 (95% confidence interval [95% CI] 0.85–0.99) with heterogeneity (I2=73.5, 95% CI 55.6–91.2), and the specificity was 0.92 (95% CI 0.82–0.96) with heterogeneity (I2=42.0, 95% CI 0.0–86.9). The pooled positive and negative likelihood ratios were 11.49 (95% CI 5.07–26.0) and 0.03 (95% CI 0.01–0.18), respectively. The diagnostic odds ratio was 341 (95% CI 53–2194), and the area under the receiver operating characteristic curve was 0.96 (95% CI 0.94–0.97).CONCLUSION:The findings evidence that the bone radiotracer is a valuable noninvasive approach that provides high accuracy for diagnosing TTR-CA and plays a modest role in differentiating TTR-CA from immunoglobulin amyloid light-chain cardiac amyloidosis. 99mTc-HMDP may be more accurate than 99mTc-PYP, 99mTc-DPD, and 18F-NaF in the TTR-CA detecting process, and 18F-NaF is a promising bone tracer to diagnose and differentiate TTR-CA.

Coal gangue is the solid waste from the coal mining process. About 1 billion tons of coal gangue is discharged every year in the world. Coal gangue is usually piled up in the large areas and difficult to be used. Phase transformation and separation of alumina and silica minerals in coal gangue are studied in this paper in order to prompt the resource utilization of coal gangue. The results show that the phase transformation of kaolinite in coal gangue during high-temperature calcination is in the following way: kaolinite → metakaolin → spinel → mullite. Active silica mineral is released during the phase transition process, which can be separated from other minerals by caustic leaching. The optimal calcination temperature of coal gangue is 1050 ± 50 °C while the caustic leaching temperature is 85 °C and the leaching time should be kept between 60 and 80 min. The modulus of the sodium silicate solution can reach 1.0–1.1 and the alumina to silica ratio (A/S) of the desilicated residue can be raised to 1.7.

ObjectiveLiquid metal (LM) nowadays is considered a new biomedical material for medical treatment. The most common application of LM in medical therapy is taking LM as a carrier for oncology therapeutics. However, the feasibility and direct effect of LM in tumor treatment are still unknown, and how to delineate the negative resection margin (NRM) of the tumor is also a crucial problem in surgery. We aimed to inject LM into interstitial channels of extremities of mice to overlay the surface of the primary tumor to investigate the effect of LM on inhibiting tumor growth and highlight the NRM of the tumor.MethodsIn this study, all 50 BALB/c-nude female mice were used to construct the transplanted HepG2-type hepatocellular carcinoma model. One week after the establishment of the model, the mice were divided into three groups, named LM group, PBS group and Control group by injecting different liquid materials into the forelimb interstitial channel of the mice. T2WI image on MRI and Magneto-acoustic tomography (MAT) were used to show the distribution of LM and PBS in vivo. The group comparisons of tumor growth and blood tests were evaluated by one-way ANOVA and post-hoc analysis. And the biocompatibility of LM to BALB/c nude mice was evaluated by histopathological analysis of LM group and control group.ResultsThe volume change ratio of tumor was significantly lower in LM group than in PBS and Control group after 10 days of grouping. Compared with PBS and Control group, the main indexes of blood tests in LM group were significantly lower and close to normal level. In addition, the distribution of LM in vivo could be clearly observed under T2WI anatomic images and the crossprofile of the tumor in MAT. LM also has a obvious contrast in MRI T2WI and enhanced the amplitude of imaging signal in MAT.ConclusionLM may inhibit the growth of transplanted hepatoma tumor through tumor encapsulation. In vivo, tumor imaging and LM distribution imaging were achieved by MRI T2WI, which verified that LM injected with interstitial injection made the NRM of tumor more prominent and had the potential of being MRI contrast agent. At the same time, LM could also be a new conductive medium to improve the imaging quality of MAT. Moreover, LM performed mild biocompatibility.

Resistive random-access memory (RRAM) is a new memory technology that can not only realize high-density storage, but also can simulate the neural synapse for use in artificial intelligence applications. In this study, we propose an RRAM device that shows competitive resistive memory characteristics and can similarly be used as a synapse in simulation of the human visual perception nervous system. First, we demonstrate that the polyvinyl alcohol-graphene oxide (PVA@GO) hybrid material-based RRAM device offers competitive resistive memory characteristics, including long retention capability, high durability, repeatability, and mechanical flexibility. Second, we integrate the RRAM (as the artificial synapse) with a light-sensitive electronic component (a photoreceptor cell) to construct an artificial visual perception system, and realize effective emulation of light perception and conversion of light signals into synaptic signals. Under light irradiation at 532 nm, a range of versatile synaptic functions, including short-term plasticity (STP), long-term plasticity (LTP), and paired pulse facilitation (PPF), was imitated. This work provides valuable insight into the development path for next-generation high-density data storage technology, and also offers a new way to imitate the human visual neural network for multi-functional humanoid robots.

Stimuli-responsive actuating hydrogels response to the external stimulus with complex deformation behaviors based on the programmable anisotropic structure design are one of the most important smart soft materials, which have great potential applications in artificial muscles, smart values, and mini-robots. However, the anisotropic structure of one actuating hydrogel can only be programmed one time, which can only provide single actuating performance, and subsequently, has severely limited their further applications. Herein, we have explored a novel SMP/hydrogel hybrid actuator through combining polyurethane shape memory polymer (PU SMP) layer and pH-responsive polyacrylic-acid (PAA) hydrogel layer by a napkin with UV-adhesive. Owing to both the super-hydrophilicity and super-lipophilicity of the cellulose-fiber based napkin, the SMP and the hydrogel can be bonded firmly by the UV-adhesive in the napkin. More importantly, this bilayer hybrid 2D sheet can be programmed by designing a different temporary shape in heat water which can be fixed easily in cool water to achieve various fixed shapes. This hybrid with a fixed temporary shape can achieve complex actuating performance based on the bi-functional synergy of temperature-triggered SMP and pH-responsive hydrogel. The relatively high modulus PU SMP achieved high to 87.19% and 88.92% shape-fixing ratio, respectively, correspond to bending and folding shapes. The hybrid actuator can actuate with the 25.71 °/min actuating speed. Most importantly, one SMP/hydrogel bi-layer hybrid sheet was repeatedly programmed at least nine times in our research to fix various temporary 1D, 2D and 3D shapes, including bending, folding and spiraling shapes. As a result, only one SMP/hydrogel hybrid can provide various complex stimuli-responsive actuations, including the reversable bending-straightening, spiraling-unspiraling. A few of the intelligent devices have been designed to simulate the movement of the natural organisms, such as bio-mimetic “paw”, “pangolin” and “octopus”. This work has developed a new SMP/hydrogel hybrid with excellent multi-repeatable (≥9 times) programmability for high-level complex actuations, including the 1D to 2D bending and the 2D to 3D spiraling actuations, which also provides a new strategy to design other new soft intelligent materials and systems.

Hydrogel-based wet electrodes are the most important biosensors for electromyography (EMG), electrocardiogram (ECG), and electroencephalography (EEG); but, are limited by poor strength and weak adhesion. Herein, a new nanoclay-enhanced hydrogel (NEH) has been reported, which can be fabricated simply by dispersing nanoclay sheets (Laponite XLS) into the precursor solution (containing acrylamide, N, N′-Methylenebisacrylamide, ammonium persulfate, sodium chloride, glycerin) and then thermo-polymerizing at 40 °C for 2 h. This NEH, with a double-crosslinked network, has nanoclay-enhanced strength and self-adhesion for wet electrodes with excellent long-term stability of electrophysiology signals. First of all, among existing hydrogels for biological electrodes, this NEH has outstanding mechanical performance (93 kPa of tensile strength and 1326% of breaking elongation) and adhesion (14 kPa of adhesive force), owing to the double-crosslinked network of the NEH and the composited nanoclay, respectively. Furthermore, this NEH can still maintain a good water-retaining property (it can remain at 65.4% of its weight after 24 h at 40 °C and 10% humidity) for excellent long-term stability of signals, on account of the glycerin in the NEH. In the stability test of skin–electrode impedance at the forearm, the impedance of the NEH electrode can be stably kept at about 100 kΩ for more than 6 h. As a result, this hydrogel-based electrode can be applied for a wearable self-adhesive monitor to highly sensitively and stably acquire EEG/ECG electrophysiology signals of the human body over a relatively long time. This work provides a promising wearable self-adhesive hydrogel-based electrode for electrophysiology sensing; which, will also inspire the development of new strategies to improve electrophysiological sensors.

Aluminum dross, a harmful and abundant solid waste generated in aluminum industry, releases toxic ammonia and causes severe environmental pollution and public health disaster. Secondary aluminum dross (SAD) can be effectively treated by the efficient and complete decomposition of aluminum nitride (AlN). The hydrolysis behavior of AlN in SAD was evaluated by thermodynamic analysis and kinetic leaching experiments. Various factors such as temperature, time, liquid-to-solid ratio, additive type, and additive dosage were evaluated to optimize the hydrolysis of AlN. The chemical composition, mineralogical phases, particle size distribution, and morphology of SAD and leaching residue were determined by X-ray diffraction, X-ray fluorescence spectroscopy, laser particle size analysis, and scanning electron microscopy, respectively. The decomposition of AlN reached 96.24% under the following optimum conditions: leaching time of 180 min, leaching temperature of 95 °C, additive of 4 wt% sodium hydroxide, and liquid-to-solid ratio of 6 mL g−1. Meanwhile, the removal efficiency of chlorine and fluorine during leaching reached 95.63% and 69.17%, respectively. The hydrolysis data indicate that the effects of relevant factors on AlN removal are consistent with the shrinking unreacted-core model, where internal layer diffusion is the rate-controlling step. The rate-controlling step was changed to chemical reaction control with the addition of sodium hydroxide, which corrodes bayerite on the surface of AlN. The activation energy of AlN hydrolysis in SAD is 38.64 kJ mol−1.

The motion of the floating platform is one of the important factors influencing the safety of testing string. The allowable motion limits of various floating drilling platforms are discussed and their calculation formulas are presented, based on which the nonlinear dynamic response characteristics of the testing tube are investigated through ABAQUS software. Results show that an excessive offset of floating platform will cause many problems to testing tube, such as operation difficulty in rising and landing pipe string, disconnection difficulty of testing tree in case of emergency. Under heave motion and slow drift motion condition, the maximum Mises stress appears in the part closed to the upper end. The heave and horizontal motions of the platform have a superposition influence on the axial force of the pipe. So, a more precise dynamic theoretical model should be developed to study the longitudinal-transverse coupled vibration of testing string in the future.

Abstract Background Increasing studies have suggested that aberrant expression of microRNAs might play essential roles in the progression of cancers. In this study, we sought to construct a high-specific and superior microRNAs signature to improve the survival prediction of colon adenocarcinoma (COAD) patients. Methods The genome-wide miRNAs, mRNA and lncRNA expression profiles and corresponding clinical information of COAD were collected from the TCGA database. Differential expression analysis, Kaplan–Meier curve and time-dependent ROC curve were calculated and performed using R software and GraphPad Prism7. Univariate and multivariate Cox analysis was performed to evaluate the prognostic ability of signature. Functional enrichment analysis was analyzed using STRING database. Results We identified ten prognosis-related microRNAs, including seven risky factors (hsa-miR-197, hsa-miR-32, hsa-miR-887, hsa-miR-3199-2, hsa-miR-4999, hsa-miR-561, hsa-miR-210) and three protective factors (hsa-miR-3917, hsa-miR-3189, hsa-miR-6854). The Kaplan–Meier survival analysis showed that the patients with high risk score had shorter overall survival (OS) in test series. And the similar results were observed in both validation and entire series. The time-dependent ROC curve suggested this signature have high accuracy of OS for COAD. The Multivariate Cox regression analysis and stratification analysis suggested that the ten-microRNA signature was an independent factor after being adjusted with other clinical characteristics. In addition, we also found microRNA signature have higher AUC than other signature. Furthermore, we identified some miRNA-target genes that affect lymphatic metastasis and invasion of COAD patients. Conclusion In this study, we established a ten-microRNA signature as a potentially reliable and independent biomarker for survival prediction of COAD patients.

Objective: To establish a pre-operative acute ischemic stroke risk (AIS) prediction model using the deep neural network in patients with acute type A aortic dissection (ATAAD).Methods: Between January 2015 and February 2019, 300 ATAAD patients diagnosed by aorta CTA were analyzed retrospectively. Patients were divided into two groups according to the presence or absence of pre-operative AIS. Pre-operative AIS risk prediction models based on different machine learning algorithm was established with clinical, transthoracic echocardiography (TTE) and CTA imaging characteristics as input. The performance of the difference models was evaluated using the receiver operating characteristic (ROC), precision-recall curve (PRC) and decision curve analysis (DCA).Results: Pre-operative AIS was detected in 86 of 300 patients with ATAAD (28.7%). The cohort was split into a training (211, 70% patients) and validation cohort (89, 30% patients) according to stratified sampling strategy. The constructed deep neural network model had the best performance on the discrimination of AIS group compare with other machine learning model, with an accuracy of 0.934 (95% CI: 0.891–0.963), 0.921 (95% CI: 0.845–0.968), sensitivity of 0.934, 0.960, specificity of 0.933, 0.906, and AUC of 0.982 (95% CI: 0.967–0.997), 0.964 (95% CI: 0.932–0.997) in the training and validation cohort, respectively.Conclusion: The established risk prediction model based on the deep neural network method may have the big potential to evaluate the risk of pre-operative AIS in patients with ATAAD.

Stimulus-responsive hydrogels are an important member of smart materials owing to their reversibility, soft/wet properties, and biocompatibility, which have a wide range of applications in the field of intelligent actuations. However, poor mechanical property and complicated fabrication process limit their further applications. Herein, we report a light-responsive tissue paper/hydrogel composite actuator which was developed by combining inkjet-printed tissue paper with poly(N-isopropylacrylamide) (PNIPAM) hydrogel through simple in situ polymerization. Due to the high strength of natural tissue paper and the strong interaction within the interface of the bilayer structure, the mechanical property of the composite actuator was highly enhanced, reaching 1.2 MPa of tensile strength. Furthermore, the light-responsive actuation of remote manipulation can be achieved because of the stamping graphite with high efficiency of photothermal conversion. Most importantly, we also made a few remotely controlled biomimetic actuating devices based on the near-infrared (NIR) light response of this composite actuator. This work provides a simple strategy for the construction of biomimetic anisotropic actuators and will inspire the exploration of new intelligent materials.

This study focused on the intelligent model for ore pulp density in the hydrometallurgical process. However, owing to the limitations of existing instruments and devices, the feed ore pulp density of thickener, a key hydrometallurgical equipment, cannot be accurately measured online. Therefore, aiming at the problem of accurately measuring the feed ore pulp density, we proposed a new intelligent model based on the long short-term memory (LSTM) and hybrid genetic algorithm (HGA). Specifically, the HGA refers to a novel optimization search algorithm model that can optimize the hyperparameters and improve the modeling performance of the LSTM. Finally, the proposed intelligent model was successfully applied to an actual thickener case in China. The intelligent model prediction results demonstrated that the hybrid model outperformed other models and satisfied the measurement accuracy requirements in the factory well.

Abstract Background Triple negative breast cancer (TNBC) is a specific subtype of breast cancer with a poor prognosis due to its aggressive biological behaviour and lack of therapeutic targets. We aimed to explore some novel genes and pathways related to TNBC prognosis through bioinformatics methods as well as potential initiation and progression mechanisms. Methods Breast cancer mRNA data were obtained from The Cancer Genome Atlas database (TCGA). Differential expression analysis of cancer and adjacent cancer, as well as, triple negative breast cancer and non-triple negative breast cancer were performed using R software. The key genes related to the pathogenesis were identified by functional and pathway enrichment analysis and protein–protein interaction network analysis. Based on univariate and multivariate Cox proportional hazards model analyses, a gene signature was established to predict overall survival. Receiver operating characteristic curve was used to evaluate the prognostic performance of our model. Results Based on mRNA expression profiling of breast cancer patients from the TCGA database, 755 differentially expressed overlapping mRNAs were detected between TNBC/non-TNBC samples and normal tissue. We found eight hub genes associated with the cell cycle pathway highly expressed in TNBC. Additionally, a novel six-gene (TMEM252, PRB2, SMCO1, IVL, SMR3B and COL9A3) signature from the 755 differentially expressed mRNAs was constructed and significantly associated with prognosis as an independent prognostic signature. TNBC patients with high-risk scores based on the expression of the 6-mRNAs had significantly shorter survival times compared to patients with low-risk scores (P

Salt stress severely restricts the growth of plants and threatens the development of agriculture throughout the world. Worldwide studies have shown that exogenous melatonin (MT) can effectively improve the growth of plants under salt stress. Through a meta-analysis of 549 observations, this study first explored the effects of salt stress characteristics and MT application characteristics on MT regulated plant growth under salt stress. The results show that MT has a wide range of regulatory effects on plant growth indicators under salt stress, of which the regulatory effect on root indexes is the strongest, and this regulatory effect is not species-specific. The intensity of salt stress did not affect the positive effect of MT on plant growth, but the application effect of MT in soil was stronger than that in rooting medium. This meta-analysis also revealed that the foliar application of a concentration between 100–200 μM is the best condition for MT to enhance plant growth under salt stress. The results can inspire scientific research and practical production, while seeking the maximum improvement in plant salt tolerance under salt stress.

Secondary aluminum dross (SAD) is a hazardous solid waste discharged from aluminum electrolysis and processing and the secondary aluminum industries, which causes severe environmental pollution and public health disasters. The stable presence of the α-Al2O3 and MgAl2O4 phases in SAD makes it difficult for it to be efficiently utilized. A combined dry pressing and alkaline roasting process was proposed for extracting the valuable Al element from SAD. Two alkaline additives (NaOH and Na2CO3) were selected as a sodium source for extracting the aluminum source from SAD in order to perform the thermodynamic analysis and roasting experiments. The phase transition behavior and the leaching performance tests were conducted using X-ray diffraction, scanning electron microscopy, X-ray fluorescence, leaching kinetics and thermal analysis. The recovery of Al and Na reached the values of 90.79% and 92.03%, respectively, under the optimal conditions (roasting temperature of 1150 °C, Na2CO3/Al2O3 molar ratio of 1.3, roasting time of 1 h, leaching temperature of 90 °C, L/S ratio of 10 mL·g−1 and leaching time of 30 min). Meanwhile, the removal efficiency of N and Cl reached 98.93% and 97.14%, respectively. The leaching kinetics indicated that the dissolution of NaAlO2 clinkers was a first-order reaction and controlled by layer diffusion process. The green detoxification and effective extraction of the Al element from SAD were simultaneously achieved without any pretreatments.

Aiming to address the disadvantages of the low automation degree of the traditional steel measuring tape verification device, as well as the high labor intensity of metrologists, high time costs, and low measurement accuracy, this paper develops a new automatic steel measuring tape calibration device based on machine vision technology. In this study, the key components, such as the tape-winding mechanism, machine vision system, force measuring device, and tape-retracting device, were designed. Three different scribed line identification and location algorithms, processing the longest line, the closest to the starting line, the highest line, etc., were designed to adapt to different types of steel measuring tape. Lastly, indication error and measurement repeatability tests were carried out. The results showed that the standard device can carry out the verification and calibration of steel measuring tape, and the maximum repeatability of the indication error of the test objects was 0.025 mm, 0.038 mm, and 0.030 mm, respectively, and the indication error of each object was within the allowable error limits. The uncertainty evaluation of the indication error of each test object was 0.16 mm, 0.54 mm, 0.78 mm, which was not more than one third of the maximum permissible error value. Hence, the measuring principle, method, and procedure of the calibration device are shown to be scientific and feasible.

Objectives. The purpose of this study was to review the experiences with transcatheter closure of mitral PVL after surgical valve replacement. Background. Transcatheter closure of paravalvular leak (PVL) is an intricate alternative to surgical closure. But it represents one of the most intricate procedures in the field of structural heart interventions, especially for patients with mitral PVL. Methods. From January 2015 through January 2019, 35 patients with mitral PVL after valve replacement underwent transcatheter closure. We reviewed the catheter techniques, perioperative characteristics, and prognosis. The median follow-up was 26 (3–48) months. Results. Acute procedural success was achieved in 33/35 (94.3%) patients. Twenty-five patients had single mitral prosthetic valve replacements; 10 had combined aortic and mitral prosthetic valve replacements previously; 28 had mechanical valves; and 7 had bioprosthetic valves. All percutaneous procedures were performed with local anesthesia except for seven transapical cases with general anesthesia. Multiple approaches were used: transfemoral, transapical, and transseptal via an arteriovenous loop. Multiple devices were deployed. There were no hospital deaths. The procedural time was 67–300 (124 ± 62) minutes. Fluoroscopic time was 17–50 (23.6 ± 12.1) minutes. The hospital stay was 5–17 (8.3 ± 3.2) days. Complications included recurrent hemolysis, residual regurgitation, acute renal insufficiency, and anemia. Twenty-seven (77.1%) patients improved by ≥1 New York Heart Association functional class at the 1-year follow-up. Conclusions. Transcatheter mitral PVL closure requires complex catheter techniques. However, this minimally invasive treatment could provide reliable outcomes and shorter hospital stays in selected patients. This trial is registered with NCT02917980.

Background: Stroke is a common postoperative complication in patients with acute type A aortic dissection (ATAAD). We aimed to explore the preoperative imaging risk findings for postoperative new stroke in patients with ATAAD.Methods: From January 2015 to December 2018, 174 patients with ATAAD who underwent preoperative aortic computed tomography angiography (CTA) and cerebral diffusion-weighted imaging (DWI) as well as postoperative brain CT were included, and divided into DWI (+) and DWI (–) groups. Pre- and intraoperative variables were collected, and logistic regression analysis was used to determine the independent risk predictors of postoperative new stroke.Results: The incidence of postoperative new stroke was 18.4% (32/174) in patients with ATAAD. Postoperative stroke was detected in 13 (31.0%) patients in the DWI (+) group and in 19 (14.4%) patients in the DWI (–) group with significant difference (P = 0.016). In the DWI (+) group, the lesions of the cerebral infarction located in the unilateral cerebral hemisphere and distributed more than three lobes (P = 0.007) were an independent risk factor for postoperative new stroke. Hypotension (P = 0.002), retrograde ascending aorta dissection with thrombosis of the false lumen (P = 0.010), aortic arch entry (P = 0.035), and coronary artery involvement (P = 0.001) were independent risk factors for postoperative stroke in the DWI (–) cohort.Conclusions: Patients with ATAAD with cerebral infarction are more likely to develop postoperative new stroke; thus, a preoperative DWI examination may be necessary. DWI lesions distributed more than 3 lobes in the unilateral hemisphere suggest a high possibility of postoperative stroke. For patients with ATAAD with normal brain, particular attention should be given to the CTA findings of false lumen thrombosis, aortic arch entry, and coronary artery involvement to avoid postoperative stroke.

Sepsis is a prevalent severe syndrome in clinic. Vascular leakage and lung injury are important pathophysiological processes during sepsis, but the mechanism remains obscure. Microvesicles (MVs) play an essential role in many diseases, while whether MVs participate in vascular leakage and lung injury during sepsis is unknown. Using cecal ligation and puncture induced sepsis rats and lipopolysaccharide stimulated vascular endothelial cells (VECs), the role and the underlying mechanism of endothelial microvesicles (EMVs) in pulmonary vascular leakage and lung injury were observed. The role of MVs from sepsis patients was verified. The results showed that the concentration of MVs in blood was significantly increased after sepsis. MVs from sepsis rats and patients induced apparent pulmonary vascular leakage and lung injury, among which EMVs played the dominant role, in which miR-23b was the key inducing factor in vascular leakage. Furthermore, downregulation and upregulation of miR-23b in EMVs showed that miR-23b mainly targeted on ZO-1 to induce vascular leakage. MVs from sepsis patients induced pulmonary vascular leakage and lung injury in normal rats. Application of classic antidepressants amitriptyline reduced the secretion of EMVs, and alleviated vascular leakage and lung injury. The study suggests that EMVs play an important role in pulmonary vascular leakage and lung injury during sepsis by transferring functional miR-23b. Antagonizing the secretion of EMVs and the miR-23b might be a potential target for the treatment of severe sepsis.

BackgroundVascular leakage is a common complication of hemorrhagic shock. Endothelial glycocalyx plays a crucial role in the protection of vascular endothelial barrier function. Hydroxyethyl starch (HES) is a commonly used resuscitation fluid for hemorrhagic shock. However, whether the protective effect of HES on vascular permeability after hemorrhagic shock is associated with the endothelial glycocalyx is unclear.MethodsUsing hemorrhagic shock rat model and hypoxia treated vascular endothelial cells (VECs), effects of HES (130/0.4) on pulmonary vascular permeability and the relationship to endothelial glycocalyx were observed.ResultsPulmonary vascular permeability was significantly increased after hemorrhagic shock, as evidenced by the increased permeability of pulmonary vessels to albumin-fluorescein isothiocyanate conjugate (FITC-BSA) and Evans blue, the decreased transendothelial electrical resistance of VECs and the increased transmittance of FITC-BSA. The structure of the endothelial glycocalyx was destroyed, showing a decrease in thickness. The expression of heparan sulfate, hyaluronic acid, and chondroitin sulfate, the components of the endothelial glycocalyx, was significantly decreased. HES (130/0.4) significantly improved the vascular barrier function, recovered the thickness and the expression of components of the endothelial glycocalyx by down-regulating the expression of heparinase, hyaluronidase, and neuraminidase, and meanwhile increased the expression of intercellular junction proteins ZO-1, occludin, and VE-cadherin. Degradation of endothelial glycocalyx with degrading enzyme (heparinase, hyaluronidase, and neuraminidase) abolished the beneficial effect of HES on vascular permeability, but had no significant effect on the recovery of the expression of endothelial intercellular junction proteins induced by HES (130/0.4). HES (130/0.4) decreased the expression of cleaved-caspase-3 induced by hemorrhagic shock.ConclusionsHES (130/0.4) has protective effect on vascular barrier function after hemorrgic shock.The mechanism is mainly related to the protective effect of HES on endothelial glycocalyx and intercellular junction proteins. The protective effect of HES on endothelial glycocalyx was associated with the down-regulated expression of heparinase, hyaluronidase, and neuraminidase. HES (130/0.4) had an anti-apoptotic effect in hemorrhagic shock.

Myocardial ischemia is a condition with insufficient oxygen supporting the heart tissues, which may result from myocardial infarction or trauma-induced hemorrhagic shock. In order to develop better preventive and therapeutic strategies for myocardial ischemic damage, it is important that we understand the mechanisms underlying this type of injury. Mitochondrial-derived vesicles (MDVs) have been proposed as a novel player in maintaining mitochondrial quality control. This study aimed to investigate the role and possible mechanisms of MDVs in ischemia/hypoxia-induced myocardial apoptosis. H9C2 cardiomyocytes were used for the cellular experiments. A 40% fixed blood volume hemorrhagic shock rat model was used to construct the acute general ischemic models. MDVs were detected using immunofluorescence staining with PDH and TOM20. Exogenous MDVs were reconstituted in vitro from isolated mitochondria under different hypoxic conditions. The results demonstrate that MDV production was negatively correlated with cardiomyocyte apoptosis under hypoxic conditions; exogenous MDVs inhibited hypoxia-induced cardiomyocyte apoptosis; and MDV-mediated protection against hypoxia-induced cardiomyocyte apoptosis was accomplished via Bcl-2 interactions in the mitochondrial pathway. This study provides evidence that MDVs protect cardiomyocytes against hypoxic damage by inhibiting mitochondrial apoptosis. Our study used a novel approach that expands our understanding of MDVs and highlights that MDVs may be part of the endogenous response to hypoxia designed to mitigate damage. Strategies that stimulate cardiomyocytes to produce cargo-specific MDVs, including Bcl-2 containing MDVs, could theoretically be helpful in treating ischemic/hypoxic myocardial injury.

Brain computer interface (BCI)-based training is promising for the treatment of stroke patients with upper limb (UL) paralysis. However, most stroke patients receive comprehensive treatment that not only includes BCI, but also routine training. The purpose of this study was to investigate the topological alterations in brain functional networks following comprehensive treatment, including BCI training, in the subacute stage of stroke. Twenty-five hospitalized subacute stroke patients with moderate to severe UL paralysis were assigned to one of two groups: 4-week comprehensive treatment, including routine and BCI training (BCI group, BG, n = 14) and 4-week routine training without BCI support (control group, CG, n = 11). Functional UL assessments were performed before and after training, including, Fugl-Meyer Assessment-UL (FMA-UL), Action Research Arm Test (ARAT), and Wolf Motor Function Test (WMFT). Neuroimaging assessment of functional connectivity (FC) in the BG was performed by resting state functional magnetic resonance imaging. After training, as compared with baseline, all clinical assessments (FMA-UL, ARAT, and WMFT) improved significantly (p < 0.05) in both groups. Meanwhile, better functional improvements were observed in FMA-UL (p < 0.05), ARAT (p < 0.05), and WMFT (p < 0.05) in the BG. Meanwhile, FC of the BG increased across the whole brain, including the temporal, parietal, and occipital lobes and subcortical regions. More importantly, increased inter-hemispheric FC between the somatosensory association cortex and putamen was strongly positively associated with UL motor function after training. Our findings demonstrate that comprehensive rehabilitation, including BCI training, can enhance UL motor function better than routine training for subacute stroke patients. The reorganization of brain functional networks topology in subacute stroke patients allows for increased coordination between the multi-sensory and motor-related cortex and the extrapyramidal system. Future long-term, longitudinal, controlled neuroimaging studies are needed to assess the effectiveness of BCI training as an approach to promote brain plasticity during the subacute stage of stroke.

A circular grating angle encoder is a key component in the dynamic torque calibration system. To improve the accuracy of an angle measurement, in this paper, the source of the angle measurement error of the circular grating is analyzed; an eccentricity error model and an inclination error model are proposed, respectively; further, these two models are combined to establish a total error model. Through the simulation study with the models, the conditions, in which the eccentricity error or inclination error can be ignored, are discussed. The calibration and compensation methods of the angle measurement error are given, and a progressive error compensation function which integrates the first harmonic fitting and the second harmonic fitting is obtained. An experiment is performed to verify the proposed calibration and compensation methods. The peak-to-peak value of the compensated angle measurement error of the single reading head can be reduced by about 93.76%, which approximates to the error of the mean value of the double reading heads. The experimental results show that the error calibration and compensation method based on the proposed error model can effectively compensate the angle measurement error of the circular grating with a single reading head, and obtain a high-precision measurement angle.

The landing string is an important component of deepwater riserless drilling systems. Determination of the dynamic characteristics of the landing string plays an essential role in its design for ensuring its safe operation. In this paper, a dynamic model is developed to investigate the dynamic response characteristics of a landing string, where a landing string in a marine environment is modeled as a flexible slender tube undergoing coupled transverse and axial motions. The heaving motion of the drilling platform is taken as the upper boundary condition and the motion of the drilling bit caused by the interaction between the rock and the bit as the lower boundary condition. A semiempirical Morison equation is used to simulate the effect of the load imposed by the marine environment. The dynamic model, which is nonlinearly coupled and multibody, is discretized by a finite element method and solved by the Newmark technique. Using the proposed model, the dynamic responses of the displacement, axial force, and moment in the landing string are investigated in detail to find out the influences of driving depth of surface catheter, platform motion, bit movement, and marine environment on the dynamical characteristics of the landing string.

In this study, a water-model experiment and numerical simulation were carried out in a pilot ISASMELT furnace to study the factors affecting mixing time. The experimental results were compared to the simulation results to test the accuracy of the latter. To study the internal factors that affect the mixing time, the turbulent viscosity and flow field were calculated using simulation. In addition, following previous research, external factors that influence the mixing time including the depth of the submerged lance, lance diameter, gas flow rate, and the presence of a swirler were studied to investigate their effect on the flow regime. The results indicated that the mixing time is controlled by the turbulent viscosity and velocity vector. In addition, it was found that the lance diameter should not exceed 3.55 cm to maintain sufficient energy for stirring the bath. Finally, the optimal gas flow rate that offers the best mixing efficiency was found to be 50 Nm3/h.

Mitogen-activated protein kinases (MAPKs) play central roles in plant developmental processes, hormone signaling transduction, and responses to abiotic stress. However, no data are currently available about the MAPK family in cassava, an important tropical crop. Herein, 21 MeMAPK genes were identified from cassava. Phylogenetic analysis indicated that MeMAPKs could be classified into four subfamilies. Gene structure analysis demonstrated that the number of introns in MeMAPK genes ranged from 1 to 10, suggesting large variation among cassava MAPK genes. Conserved motif analysis indicated that all MeMAPKs had typical protein kinase domains. Transcriptomic analysis suggested that MeMAPK genes showed differential expression patterns in distinct tissues and in response to drought stress between wild subspecies and cultivated varieties. Interaction networks and co-expression analyses revealed that crucial pathways controlled by MeMAPK networks may be involved in the differential response to drought stress in different accessions of cassava. Expression of nine selected MAPK genes showed that these genes could comprehensively respond to osmotic, salt, cold, oxidative stressors, and abscisic acid (ABA) signaling. These findings yield new insights into the transcriptional control of MAPK gene expression, provide an improved understanding of abiotic stress responses and signaling transduction in cassava, and lead to potential applications in the genetic improvement of cassava cultivars.