Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation

Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury.

Large eddy simulation of supersonic flow in ducts with complex cross-sections

Large Eddy Simulation(LES)has been employed for the investigation of supersonic flow characteristics in five ducts with varying cross-sectional geometries.The numerical results reveal that flow channel configurations exert a considerable influence on the mainstream flow and the near-wall flow behavior.In contrast to straight ducts,square-to-circular and rectangular-to-circular ducts exhibit thicker boundary layers and a greater presence of vortex structures.Given the same inlet area,rectangular-to-circular ducts lead to higher flow drag force and total pressure loss than square-to-circular ducts.Characterized by the substantial flow separation and shock waves,the"S-shaped duct shows significant vertically-asymmetric characteristics.

Low complexity MIMO sonar imaging using a virtual sparse linear array

A multiple-input multiple-output（MIMO） sonar can synthesize a large-aperture virtual uniform linear array（ULA） from a small number of physical elements. However, the large aperture is obtained at the cost of a great number of matched filters with much heavy computation load. To reduce the computation load, a MIMO sonar imaging method using a virtual sparse linear array（SLA） is proposed, which contains the offline and online processing. In the offline processing, the virtual ULA of the MIMO sonar is thinned to a virtual SLA by the simulated annealing algorithm, and matched filters corresponding to inactive virtual elements are removed. In the online processing, outputs of matched filters corresponding to active elements are collected for further multibeam processing and hence, the number of matched filters in the echo processing procedure is effectively reduced. Numerical simulations show that the proposed method can reduce the computation load effectively while obtaining a similar imaging performance as the traditional method.

Compensating for intensity loss in a large-aperture MIMO sonar imaging system

To reduce the computation burden of a large-aperture multiple-input multiple-output（MIMO） sonar imaging system,the phase-shift beamformer（PSBF） is used at the cost of bringing the intensity loss（IL）.The cause of the IL is analyzed in detail and a variable termed as IL factor is defined to quantify the loss amount.To compensate for the IL,two methods termed as intensity compensation for the PSBF（IC-PSBF） and the hybrid beamforming（HBF）,respectively,are proposed.The IC-PSBF uses previously estimated IL factors to compensate for output intensities of all PSBFs;and the HBF applies the IC-PSBF to the center beam region and the shifted-sideband beamformer（SSBF） to the side beam region,respectively.Numerical simulations demonstrate the effectiveness of the two proposed methods.

马赫数6飞行条件圆截面超燃冲压发动机流动燃烧特征分析

本文基于RANS方法对马赫数6飞行条件下的乙烯燃料圆截面超燃冲压发动机燃烧流场开展了数值研究,计算中采用了压力相关的火焰面/进度变量模型,得到的数值结果与试验吻合,并据此分析了0.18和0.06当量比工况的火焰结构和燃烧特征。计算表明,0.18当量比工况释热强度高,在流场中形成了热壅塞,并且预混燃烧和扩散燃烧共同主导了整体的释热。而0.06当量比工况流道中心仍是超声速状态,扩散火焰主导了整体的释热。2个工况中,射流背风区和轴对称凹腔都是重要的反应区,其中射流背风区释热强度高,而凹腔起到了增强混合和提高燃烧效率的重要作用。

Effect of kerosene injection states on mixing and combustion characteristics in a cavity-based supersonic combustor

It has been found that the static pressure distribution along the axial direction of liquid kerosene is lower than that of the gaseous kerosene under the same flow condition and overall equivalent ratio from previous studies.To further investigate this phenomenon,a compressible two-phase parallel simulation method is utilized to analyze the mixing and combustion characteristics of gaseous and liquid kerosene jets in a cavity-based supersonic combustor.The numerical results are consistent with the experiments and demonstrate that gaseous injection leads to a cavity shear layer that dives deeper into the cavity,forming two recirculation zones in the front and rear of the cavity.In contrast,the cavity shear layer is closer to the mainstream during liquid injection,and only a large recirculation zone is formed in the rear of the cavity.As a result of the cavity shear layer and the recirculating flow,the fuel vapor of gaseous injection accumulates in the front of the cavity,while for the liquid injection,the fuel vapor disperses in the cavity,cavity shear layer,and the region above,and the rear of the cavity has a higher fuel vapor concentration than the front.This unique fuel distribution causes the combustion area to be concentrated in the cavity during the gaseous injection but dispersed inside and downstream of the cavity during the liquid injection.As a result,forming a thermal throat under the same conditions is more challenging during liquid injection,and the generated static pressure distribution is lower than that during the gaseous injection.

Chemical oxygen demand oxidation via sustained-release persulfate balls: a rate-compatibility study of flow velocity, releasing, and oxidation

Identification of chemical oxygen demand(COD)in municipal solid waste(MSW)landfill leachates is a challenging problem.This paper investigated the feasibility of using sodium persulfate(PS),a strong oxidant,as a permeable reactive barrier(PRB)filling material.Firstly,sustained-release persulfate balls were manufactured to adjust the release rate of persulfate,the oxidation agent.In addition,Fe(II)-loaded activated carbon(Fe-AC)was used to help with an even distribution of Fe(II)in the porous medium(PRB in this case).Then,the oxidation efficiency and kinetic rate of COD removal by the sustained-release balls were subjected to batch tests.A mass ratio of 1:1.4:0.24:0.7 for PS:cement:sand:water was the most efficient for COD removal(95%).The breakthrough curve for a 5 mm sustained-release ball revealed that the retardation factor was 1.27 and that the hydrodynamic dispersion coefficient was 15.6 cm^(2)/d.The corresponding half-life of COD oxidation was 0.43 d,which was comparable with the half-life of PS release from sustained-release balls(0.56 d).The sustained-release persulfate balls were shown to be an economical material with a simple recipe and production method when catalyzed by Fe-AC.Compared with cutting-edge methods,sustained-release balls used in PRBs offer significant advantages in terms of both effectiveness and economy for the preparation of sustained-release and catalytic materials.These results verified the feasibility of using sustained-release persulfate balls as a PRB material for COD removal.

Predesigned covalent organic framework with sulfur coordination: Anchoring Au nanoparticles for sensitive colorimetric detection of Hg(Ⅱ)

Targeted construction of new covalent organic frameworks(COFs)with specific purposes and rationalities to build colorimetric assay platform for environmental pollutant monitoring have attracted increasing interest.However,it is still challenging due to lack of available coordination sites inside COFs pores and only a slight bonding ability for anchoring metal.In this work,a two-dimensional(2D)COFs(termed as Tz-COF)with high crystallinity,excellent chemical stability,and abundant sulfur coordination in its skeletons was synthesized and used for the confined growth of Au NPs.It was found that the Au NPs showed significant dispersibility for the support of Tz-COF.The proposed Tz-COF@Au NPs possessed outstanding Hg^(2+)-activated peroxidase-like activity benefited from physicochemical properties of gold amalgam and synergistic effect between COFs and Au NPs to oxidize chromogenic substrate.Based on highly efficient activity and distinctive color evolution,the strategy for detecting Hg^(2+)was developed and successfully applied to determine the content of Hg^(2+)in real environmental samples.This work manifests that a potential strategy to establish a colorimetric assay platform for environmental pollutant monitoring based on the targeted manufacturing of novel COFs with specific functions.

Molecular-scale co-assembly membranes derived from keplerate cluster:carbonic anhydrase-mimicking nanocapsules for enhanced CO_(2)/N_(2)separation

The development of CO_(2)separation membranes with high permeability and high selectivity,as well as ultra-thin selective layers,has always been challenging.Herein,a molecular-scaled co-assembly strategy is employed to fabricate the Pebax-Mo_(132)(Pebax=polyether-block-amide copolymer;Mo_(132)=(NH_(4))_(42)[Mo_(72)^(Ⅵ)Mo_(60)^(Ⅴ)O_(372)(CH_(3)COO)_(30)(H_(2)O)_(72)])membranes.The optimal selfstanding membrane,Pebax-Mo_(132)-5%,shows a CO_(2)permeability of~384 Barrer and an ultra-high ideal CO_(2)/N_(2)selectivity of~244,outperforming most membranes reported in the literature.The CO_(2)permeability and ideal CO_(2)/N_(2)selectivity are increased by 70%and 367%,respectively,compared with the pristine Pebax membrane.A thin-film composite membrane prepared by spin-coating technique on a support membrane with gutter layers also exhibits a CO_(2)permeance of 838 GPU and a CO_(2)/N_(2)selectivity of 136.Such excellent performance can be attributed to the following reasons:(1)strong hydrogen bonding interactions between{Mo_(132)}clusters and Pebax confer excellent interfacial compatibility to the mixed matrix membranes;(2)incorporation of hollow{Mo_(132)}clusters into the Pebax molecular chain decreases the crystallinity of Pebax,and thereby accelerates the chain dynamics and increases the free volume of the membrane;(3)in situ diffuse reflectance infrared Fouriertransform spectroscopy demonstrates that the{Mo_(132)}clusters can effectively catalyze the hydration reaction of CO_(2)and promote the transport of CO_(2);(4)furthermore,the 0.35 nm pores of the crown ether-type{Mo_(9)O_(9)}allow the accurate size sieving of CO_(2)(0.33 nm)and N_(2)(0.36 nm)molecules.

双圆盘Hardy空间上的子模[q(θ,φ)]的Hilbert-Schmidt性

设M是双圆盘Hardy空间H^(2)(D^(2))上的一个闭子空间,如果M在坐标函数z和w的作用下不变,则称M为子模.“是否每个有限生成的子模都是Hilbert-Schmidt的”是一个尚未解决的公开问题.本文证明由q(θ(z),φ(w))生成的子模都是Hilbert-Schmidt的,其中,q是任意齐次多项式,θ和φ是两个内函数.

Thiophene-based covalent organic frameworks for highly efficient iodine capture

Development of adsorbent materials for highly efficient iodine capture is high demand from the perspective of ecological environment and human health. Herein, the two kinds of thiophene-based covalent organic frameworks(COFs) with different morphologies were synthesized by solvothermal reaction using thieno[3,2-b]thiophene-2,5-dicarbaldehyde(TT) as the aldehyde monomer and tri(4-aminophenyl)benzene(PB) or tris(4-aminophenyl)amine(PA) as the amino monomer(denoted as PB-TT COF and PA-TT COF) and the as-prepared two heteroatoms-rich COFs possessed many excellent properties,including high thermal stability and abundant binding sites. Among them, PB-TT COF exhibited ultra-high iodine uptake up to 5.97 g/g in vapor, surpassing most of adsorbents previously reported, which was ascribed to its high specific surface(1305.3 m2/g). Interestingly, PA-TT COF with low specific surface(48.6m2/g) showed good adsorption ability for iodine in cyclohexane solution with uptake value of 750 mg/g,which was 2.38 times higher than that obtained with PB-TT COF due to its unique sheet-like morphology.Besides, the two COFs possessed good reusability, high selectivity and iodine retention ability. Based on experimental results, the adsorption mechanisms of both COFs were studied, revealing that iodine was captured by the physical-chemical adsorption. Furthermore, the both COFs showed excellent adsorption ability in real radioactive seawater treated safely, demonstrating their great potential in real environment.

Review on recent progress in on-line monitoring technology for atmospheric pollution source emissions in China

Emissions from mobile sources and stationary sources contribute to atmospheric pollution in China,and its components,which include ultrafine particles(UFPs),volatile organic compounds(VOCs),and other reactive gases,such as NH3and NOx,are the most harmful to human health.China has released various regulations and standards to address pollution from mobile and stationary sources.Thus,it is urgent to develop online monitoring technology for atmospheric pollution source emissions.This study provides an overview of the main progress in mobile and stationary source monitoring technology in China and describes the comprehensive application of some typical instruments in vital areas in recent years.These instruments have been applied to monitor emissions from motor vehicles,ships,airports,the chemical industry,and electric power generation.Not only has the level of atmospheric environment monitoring technology and equipment been improving,but relevant regulations and standards have also been constantly updated.Meanwhile,the developed instruments can provide scientific assistance for the successful implementation of regulations.According to the potential problem areas in atmospheric pollution in China,some research hotspots and future trends of atmospheric online monitoring technology are summarized.Furthermore,more advanced atmospheric online monitoring technology will contribute to a comprehensive understanding of atmospheric pollution and improve environmental monitoring capacity.

Retrieval of refractive index of ultrafine single particle using hygroscopic growth factor obtained by high sensitive surface plasmon resonance microscopy

When exposed to different relative humidities (RHs),the optical properties of atmospheric aerosols will change because of changes in the aerosol particle size and complex refractive index (RI),which will affect haze formation and global climate change.The potential contributions of ultrafine particles to the atmospheric optical characteristics and to haze spreading cannot be ignored because of their high particle number concentrations and strong diffusibility;measurement of the optical properties of wet ultrafine particles is thus highly important for environmental assessment.Therefore,a surface plasmon resonance microscopy with azimuthal rotation illumination (SPRM-ARI) system is designed to determine the RIs of single particle aerosols with diameters of less than 100 nm in the hygroscopic growth process.Measurements are taken using mixed single particles with different mass ratios.The RIs of mixed single aerosols at different RHs are retrieved by measuring the scattering light intensity using the SPRM-ARI system and almost all the RIs of the bicomponent particles with different mass ratios decrease with increasing water content under high RH conditions.Finally,for each of the bicomponent particles,the maximum standard deviations for the retrieved RI values are only 2.06×10^(-3),3.08×10^(-3)and 3.83×10^(-3),corresponding to the NaCl and NaNO_(3)bicomponent particles with a 3:1 mass ratio at 76.0%RH,the NaCl and glucose particles with a 1:3 mass ratio at 89.0%RH,and the NaCl and OA particles with a 1:1 mass ratio at 78.0%RH,respectively;these results indicate that the high-sensitivity SPRM-ARI system can measure the RI effectively and accurately.

Hilbert-Schmidtness of Submodules in H^(2)(D^(2))Containing(z)-β(w)

A closed subspace M of the Hardy space H^(2)(D^(2))over the bidisk is called submodule if it is invariant under multiplication by coordinate functions z and w.Whether every finitely generated submodule is Hilbert-Schmidt is an unsolved problem.This paper proves that every finitely generated submodule M containing(z)-Φ(w)is Hilbert-Schmidt,where 0(z),p(w)are two finite Blaschke products.

投影谱的光滑性

算子组的联合谱研究是算子理论的一个重要而充满挑战的研究方向.本文研究算子组的投影联合谱的相关问题.本文的主要结果肯定地回答了He等(2017)提出的一个公开问题,并利用截断Toeplitz算子具体地构造了相关的例子.

Facile preparation of nano-g-C_(3)N_(4)/UiO-66-NH_(2) composite as sorbent for high-efficient extraction and preconcentration of food colorants prior to HPLC analysis

In this work,the nano-g-C_(3)N_(4)/Ui O-66-NH_(2)composite was prepared by one-step solvothermal method.The as-prepared composite was characterized by scanning electron microscopy,Brunner-Emmet-Teller measurement,energy dispersive spectrometer,X-ray diffraction,and Fourier transform infrared spectroscopy.By using nano-g-C_(3)N_(4)/Ui O-66-NH_(2)composite as sorbent,a dispersive solid-phase extraction coupled with high-performance liquid chromatography was developed to sensitive analysis of food colorants including tartrazine,amaranth,carmine,sunset yellow,allura red and bright blue.The experiment parameters including the amount of sorbent,adsorption time,the p H of adsorption solution,desorption time,desorption solvent,the p H of desorption solution as well as the proportion between desorption solvent and buffer solvent were investigated.Under the optimized conditions,the limits of detection(S/N=3) and limits of quantitation (S/N=10) were determined in the ranges of 0.08-0.8 and 0.2-2.0 ng/m L,respectively.With the developed sample pretreatment method,carmine and brilliant blue were determined from blueberry juice by HPLC-DAD.The contents were calculated as 1.53μg/m L and0.17μg/mL,respectively.

Experimental study on oxidative decomposition of nitrobenzene in aqueous solution by honeycomb ceramic-catalyzed ozonation

The ozonation of nitrobenzene in aqueous solu-tion was carried out in a semi-batch reactor to investigate the degradation efficiency,the effect factors,and the reaction mechanism,where honeycomb ceramic was used as a cata-lyst.The presence of honeycomb ceramic could improve the degradation rate of nitrobenzene by 15.46%compared to the results of ozonation alone.Under the conditions of this exper-iment,the degradation rate of honeycomb ceramic-catalyzed ozonation increased by 12.94%with the increase of the amount of catalyst from 1 to 5 blocks.The degradation rates all increased greatly with the increase of temperature and pH of the solution in the processes of honeycomb ceramic-catalyzed ozonation and ozonation alone.But,when the pH of the solution increased to 9.50,the advantage of the honey-comb ceramic-catalyzed ozonation process would be lost.The experimental findings indicated that in the processes of ozonation alone and honeycomb ceramic-catalyzed ozona-tion,nitrobenzene was primarily oxidized by•OH free radical in aqueous solution.The adsorption of nitrobenzene was too limited to have an important influence on the degradation rate of nitrobenzene.With the same total dosage of applied ozone,the multiple step addition of ozone showed much higher removal efficiency than that obtained by one step in the two processes.

Bifurcation analysis of dual-sidestay landing gear locking performance considering joint clearance

Sidestay lock mechanism is an important part of landing gear system,and the locking performance can be analyzed based on changes in its stability.However,during numerical continuation analysis of fully-rigid dual-sidestay landing gear without clearance,it has been found that the appearance of bifurcation points does not necessarily imply that both sidestay links can be locked synchronously.This problem reveals the limitations of fully-rigid model with ideally-articulated in solving dual-sidestay mechanisms with extremely high motion sensitivity.Therefore,this study proposes a bifurcation analysis method for synchronous locking of dual-sidestay landing gears,which takes into consideration the joint clearance.For in-depth analysis of this problem,we initially build kinematic and mechanical models of a landing gear mechanism that consider joint clearance.Then,the models are solved based on continuation.The fundamental causes of synchronous locking are discussed in detail,and the number of bifurcation points is found to be closely related to whether the landing gear is completely locked.Finally,the effects of structural parameters on the synchronous locking are analyzed,and the feasible region of parameters satisfying synchronous locking condition is given,which agrees well with the test results.

Adenylate cyclase activity of TIR1/AFB links cAMP to auxin-dependent responses

The phytohormone auxin is essential for plant growth and development as well as cellular and systemic responses to environmental cues.The auxin receptor TRANSPORT INHIBITOR RESPONSE 1/AUXIN-SIGNALING F-BOX(TIR1/AFB)lies within an E3 ubiquitin ligase complex(SCF^(TIR1/AFB))consisting of Skp,Cullin,and F-box proteins.Auxin brings together TIR1/AFB and the transcriptional repressor Auxin/INDOLE-3-ACETIC ACID(Aux/IAA),which allows the SCF^(TIR1/AFB) complex to transfer activated ubiquitin to Aux/IAA,thereby targeting it for proteasomal degradation.This liberates the transcription factors AUXINRESPONSE FACTORs for auxin-dependent transcription(Lavy and Estelle,2016).

Identification of potential nitric oxide-sensing proteins using the H-NOX motif

NO Sensing Is Universal and Ancient During the anoxic stages of the early Earth,nitric oxide(NO)served as a major nitrogen source for prokaryotes,which,against a backdrop of an increasingly oxygen-rich atmosphere,evolved NO signaling mechanisms for processes including the regulation of communal behavior(Plate and Marietta,2012).In humans,NO lowers blood pressure,acts as neurotransmitter,and activates macrophages during immune responses(Farah et al.,2018).Animal NO-sensing proteins share structural similarity with those of early prokaryotes,as exemplified by the activation of soluble guanylate cyclases(sGCs),in which a heme-containing domain enables NO sensing by the heme NO/oxygen(H-NOX),thus indicating ancient evolutionary origin.In plants,NO signals for defense,growth,and developmental processes(Durner et al.,1998;Domingos et al.,2015)appeared to occur mainly through protein S-nitrosation,where the redox changes of sensing proteins could directly modulate enzymatic activities thereby causing the release of reactive oxygen intermediates,or by alteration of methylation patterns of defense genes that,in turn,affect programmed cell death during stress responses(Tada et al.,2008;Yun et al.,2011;Hu et al.,2017).