The functions of exosomes targeting astrocytes and astrocyte-derived exosomes targeting other cell types

Astrocytes are the most abundant glial cells in the central nervous system;they participate in crucial biological processes,maintain brain structure,and regulate nervous system function.Exosomes are cell-derived extracellular vesicles containing various bioactive molecules including proteins,peptides,nucleotides,and lipids secreted from their cellular sources.Increasing evidence shows that exosomes participate in a communication network in the nervous system,in which astrocyte-derived exosomes play important roles.In this review,we have summarized the effects of exosomes targeting astrocytes and the astrocyte-derived exosomes targeting other cell types in the central nervous system.We also discuss the potential research directions of the exosome-based communication network in the nervous system.The exosome-based intercellular communication focused on astrocytes is of great significance to the biological and/or pathological processes in different conditions in the brain.New strategies may be developed for the diagnosis and treatment of neurological disorders by focusing on astrocytes as the central cells and utilizing exosomes as communication mediators.

Experimental study of the effect of gas discharge on ionic liquid electrospray

Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parameters. In this study, electrospray experiments were conducted on the ionic liquid EMI-BF4. The observations revealed that the operating modes of the ionic liquid depend on the voltage polarity at high voltages. Additionally, a correspondence between the operating mode of ILE and the current signal in the circuit was established. The shape of the liquid cone formed at the needle tip bore a striking resemblance to the plume of corona discharge, suggesting that the motion trajectory of electrons influenced the curvature of the liquid cone. Steamer theory provided a clear explanation for the change in curvature as the voltage increased.

Co-Ru alloy nanoparticles decorated onto two-dimensional nitrogen doped carbon nanosheets towards hydrogen/oxygen evolution reaction and oxygen reduction reaction

Constructing highly-efficient electrocatalysts toward hydrogen evolution reaction(HER)/oxygen evolution reaction(OER)/oxygen reduction reaction(ORR)with excellent stability is quite important for the development of renewable energy-related applications.Herein,Co-Ru based compounds supported on nitrogen doped two-dimensional(2D)carbon nanosheets(NCN)are developed via one step pyrolysis procedure(Co-Ru/NCN)for HER/ORR and following low-temperature oxidation process(Co-Ru@RuO_(x)/NCN)for OER.The specific 2D morphology guarantees abundant active sites exposure.Furthermore,the synergistic effects arising from the interaction between Co and Ru are crucial in enhancing the catalytic performance.Thus,the resulting Co-Ru/NCN shows remarkable electrocatalytic performance for HER(70 mV at 10 mA cm^(-2))in 1 M KOH and ORR(half-wave potential E_(1/2)=0.81 V)in 0.1 M KOH.Especially,the Co-Ru@RuO_(x)/NCN obtained by oxidation exhibits splendid OER performance in both acid(230 mV at 10 mA cm^(-2))and alkaline media(270 mV at 10 mA cm^(-2))coupled with excellent stability.Consequently,the fabricated two-electrode water-splitting device exhibits excellent performance in both acidic and alkaline environments.This research provides a promising avenue for the advancement of multifunctional nanomaterials.

Growing Biomorphic Transition Metal Dichalcogenides and Their Alloys Toward High Permeable Membranes and Efficient Electrocatalysts Applications

3D architecratured transition metal dichalcogenides constructed by atomically thin layers are appealing building blocks in various applications,such as catalysts,energy storage,conversions,sensors,and so on.However,the direct growth of 3D transition metal dichalcogenides architectures with high crystal quality and well-controlled size/thickness remains a huge challenge.Herein,we report a facile,highly-repeatable,and versatile chemical vapor deposition strategy,for the mass production of high-quality 3D-architecratured transition metal dichalcogenides(e.g.,MoS_(2),WS_(2),and ReS_(2))and their alloys(e.g.,W_(x)Mo(1–x)S_(2)and Rex Mo_((1–x))S_(2))nanosheets on naturally abundant and low-cost diatomite templates.Particularly,the purified transition metal dichalcogenides products exhibit unique and designable 3D biomorphic hierarchical microstructures,controllable layer thicknesses,tailorable chemical compositions,and good crystallinities.The weak interlayer interactions endow them with good dispersity in solutions to form stable additive-free inks for solution-processing-based applications,for example,high-permeable and high-stable separation membranes for water purification,and efficient electrocatalysts for hydrogen evolution reactions.This work paves ways for the low-cost,mass production of versatile transition metal dichalcogenides powder-like materials with designable structures and properties,toward energy/environmental-related applications and beyond.

Recent advancements in metal-organic frameworks for green applications

A series of environmental and energy issues,such as global warming,water pollution,acid rain,and energy shortage,have to be settled urgently.Metal-organic frameworks(MOFs)are compounds consisting of metal ions or clusters coordinated to organic ligands,which show great promise for alleviating or mitigating these challenges owing to their outstanding physical and chemical properties.In this review,we summarize the recent advances of MOFs in the fields of green applications,including carbon capture,harmful gas removal,sewage treatment,and green energy storage.In addition,the challenges and prospects of the large-scale commercialized use of MOFs in handling environmental issues are also discussed.

Dynamic Performance of Straddle Monorail Curved Girder Bridge

In this work,a monorail vehicle-bridge coupling(VBC)model capable of accurately considering curve alignment and superelevation is established based on curvilinear moving coordinate system,to study the VBC vibration of straddlemonorail curved girder bridge and the relevant factors influencing VBC.While taking Chongqing Jiao Xin line as an example,the VBC program is compiled using Fortran,where the reliability of algorithm and program is verified by the results of Chongqing monorail test.Moreover,the effects of curve radius,vehicle speed,and track irregularity on the corresponding vehicle and bridge vibrations are compared and analyzed.It is observed that the test results of lateral vibration acceleration(LVA)and vertical vibration acceleration(VVA)of track beam,and LVA of vehicle,are consistent with the simulation results.Owing to the track irregularity,vibration of track beam and vehicle increases significantly.Besides,an increase in vehicle speed gradually increases the vibration of track beam and vehicle.For the curve radius(R)≤200 m,lateral and vertical vibrations of the track beam and vehicle decrease significantly with an increasing curve radius.Alternatively,when 200 m<R<600 m,the lateral vibration of the track beamand vehicle decreases slowly with an increasing curve radius,while the relevant vertical vibration remains stable.Similarly,when R≥600 m,the lateral and vertical vibrations of the track beam and vehicle tend to be stable.Accordingly,the results presented here can provide a strong reference for the design,construction,and safety assessment of existing bridges.

Bioinspired supramolecular macrocycle hybrid membranes with enhanced proton conductivity

Enhancing the proton conductivity of proton exchange membranes(PEMs)is essential to expand the applications of proton exchange membrane fuel cells(PEMFCs).Inspired by the proton conduction mechanism of bacteriorhodopsin,cucurbit[n]urils(CB[n],where n is the number of glycoluril units,n=6,7,or 8)are introduced into sulfonated poly(ether ether ketone)(SPEEK)matrix to fabricate hybrid PEMs,employing a nature-inspired chemical engineering(NICE)methodology.The carbonyl groups of CB[n]act as proton-conducting sites,while the host–guest interaction between CB[n]and water molecules offers extra protonconducting pathways.Additionally,the molecular size of CB[n]aids in their dispersion within the SPEEK matrix,effectively bridging the unconnected proton-conducting sulfonic group domains within the SPEEK membrane.Consequently,all hybrid membranes exhibit significantly enhanced proton conductivity.Notably,the SPEEK membrane incorporating 1 wt.%CB[8](CB[8]/SPEEK-1%)demonstrates the highest proton conductivity of 198.0 mS·cm^(−1) at 60°C and 100%relative humidity(RH),which is 228%greater than that of the pure SPEEK membrane under the same conditions.Moreover,hybrid membranes exhibit superior fuel cell performance.The CB[8]/SPEEK-1%membrane achieves a maximum power density of 214 mW·cm^(−2),representing a 140%improvement over the pure SPEEK membrane(89 mW·cm^(−2))at 50°C and 100%RH.These findings serve as a foundation for constructing continuous proton-conducting pathways within membranes by utilizing supramolecular macrocycles as fuel cell electrolytes and in other applications.

CD36 promotes tubular ferroptosis by regulating the ubiquitination of FSP1 in acute kidney injury

Reactive oxidative species(ROos)production-driven ferroptosis plays a role in acute kidney injury(Akl).However,its exact molecular mechanism is poorly understood.Scavenger receptor CD36 has important roles in oxidizing lipids,lipid accumulation,metabolic syndrome,and insulin resistance in chronic kidney disease,but its roles remain unexplored in AKl.The present study investigated the role and mechanism of CD36 in regulating proximal tubular cell ferroptosis and AKl.The expression of CD36 was found to be significantly up-regulated in AKI renal tissues and correlated with renal function,which might serve as an independent biomarker for AKl patients.Moreover,in adult mice subjected to AKl,deletion of CD36(CD36-/-)induced tubular cell Ros accumulation,ferroptosis activation,and renal injury.Mechanistically,combining LC-MS/MS,co-IP,and ubiquitination analyses revealed that CD36 could specifically bind to ferroptosis suppressor protein 1(FSP1)and regulate its ubiquitination at sites K16 and K24,leading to FSP1 degradation and progression of ferroptosis in AKl.The present results emphasize a novel mechanism of CD36 in cisplatin-induced AKl.The discovery of the special CD36 roles in promoting ferroptosis and AKI development by regulating the ubiquitination of FSP1 in proximal tubular cells may be potential therapeutic targets for AKl.Moreover,CD36 may play a key role in the progression of AKl.Therefore,targeting CD36 may provide a promising treatment option for AKI.

QCD sum rule study for hidden-strange pentaquarks

Inspired by the LHCb observations of hidden-charm Pc(s)states,we study their hidden-strange analog Psstates in both the[udu][■s]and[uds][■u]configurations.We investigate Ps pentaquark states in the pη′,pφ,ΛK,ΣK,andΣ*K*structures with JP=1/2-andΣ*K andΣK*with JP=3/2-and calculate their masses in the framework of QCD sum rules.Our numerical results show that the extracted hadron masses for all the pη′,pφ,ΛK,ΣK,andΣ*K*structures are significantly higher than theΣK mass threshold,and the masses forΣ*K andΣK*are also higher than the threshold of the corresponding hadron;hence,no bound state exists in such channels,which is consistent with the current experimental status.

Therapeutic strategies for acute basilar-artery occlusion

To the editor:Acute basilar-artery occlusion(aBAO)is one of the most severe forms of stroke,with an incidence of severe disability and death of up to 80%.^([1,2,3])Although several previous prospective multicenter randomized controlled trials(RCTs)involving patients with acute stroke due to large-artery occlusion in the anterior circulation have shown that endovascular thrombectomy(EVT)dramatically improves prognosis over best medical management(BMM),^([4,5])the efficacy and safety of EVT for aBAO remain controversial.

超重力环境下O3/Fenton法处理含硝基苯废水

在旋转填充床（RPB）中超重力环境下采用O3/Fenton法处理含硝基苯废水,考察了Fenton试剂投加次数、超重力因子β、液体流量、初始pH值、Fe2＋投加量、H2O2与Fe2＋摩尔比对硝基苯去除率的影响.结果表明,在硝基苯浓度175 mg/L、反应温度25℃、气体流量75 L/h、臭氧浓度40 mg/L、分3次投加Fenton试剂、溶液初始pH值4.5、超重力因子β=80、液体流量140 L/h和Fe2＋总投加量1 mmol/L、摩尔比H2O2：Fe2＋=5、循环处理40 min的条件下,硝基苯去除率和化学需氧量（COD）去除率分别为99.6%和87.6%.相近条件下,与RPB-Fenton法相比,硝基苯去除率和COD去除率分别提高了36.3%和4.5%,与RPB-O3法相比分别提高了7.2%和47.1%,与BR（鼓泡反应器）-O3/Fenton法相比分别提高了11.3%和47.8%.

等离激元增强金属-硅组合微结构近红外吸收

亚波长光栅结构的光学表面具有减反特性,这种特性在光电转换效率的应用方面具有重要意义。为了提高硅基光栅结构在近红外波段(0.78~2.50μm)的吸收率,采用在硅表面光栅空隙处加入金属Ag纳米颗粒和Al2O3介质层的方法,利用FDTD软件仿真研究不同的组合结构及颗粒的直径对光吸收率的影响,分析不同的工作波长下组合结构中特征截面的光强分布。实验结果表明,当光栅线/间比为1∶1、周期为1μm、周期凹槽内放置两层直径为0.25μm的金属Ag颗粒、且凹槽内金属颗粒上方填充覆盖Al2O3介质层时,该组合微结构在近红外波段范围内的平均吸收率理论上可达到0.463,实现吸收增强的效果。在光电转换器件的应用方面,金属颗粒-硅光栅-介质层组合微结构可以增强光吸收,进而提高光电转换效率。

强磁场生命科学与健康医疗的机遇和挑战

基于第620次香山科学会议的研讨主题和内容,从强磁设备平台、强磁场生命科学研究、铁代谢与铁磁纳米药物、强磁场健康调控等方面论述了强磁场生命科学与健康医学领域的新问题、新机遇以及面临的挑战.

金属-有机骨架材料水相合成路线研究进展

金属-有机骨架材料具有优异的物理化学性质,因而在气体储存、吸附分离、药物传输、超级电容器、催化等领域具有广阔的应用前景.然而大多数金属-有机骨架材料的合成通常需要用到大量的有机溶剂,而这些有机溶剂的使用不仅会增加金属-有机骨架材料的生产成本,且极易对环境造成影响.基于此,理想的合成路线是用水代替有害的有机溶剂,以降低成本及减轻其对环境的影响.本文总结了近期金属-有机骨架材料水相合成路线的研究进展,重点概括了不同水相合成法制备金属-有机骨架材料的机理,并分析了各种方法的优缺点.此外,还讨论了当前绿色且低成本工业化生产金属-有机骨架材料存在的问题以及未来可能的发展方向.

Safety and efficacy of stent-assisted coiling for acutely ruptured wide-necked intracranial aneurysms:comparison of LVIS stents with laser-cut stents

Background:To compare the safety and efficacy of LVIS stent-assisted coiling with those of laser-cut stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms.Methods:Patients with acutely ruptured wide-necked intracranial aneurysms treated with LVIS stent-assisted coiling(LVIS stent group)and laser-cut stent-assisted coiling(laser-cut stent group)were retrospectively reviewed from January 2014 to December 2017.Propensity score matching was used to adjust for potential differences in age,sex,aneurysm location,aneurysm size,neck width,Hunt-Hess grade,and modified Fisher grade.Perioperative procedure-related complications and clinical and angiographic follow-up outcomes were compared.Univariate and multivariate analyses were performed to determine the associations between procedure-related complications and potential risk factors.Results:A total of 142 patients who underwent LVIS stent-assisted coiling and 93 patients who underwent laser-cut stent-assisted coiling were enrolled after 1:2 propensity score matching.The angiographic follow-up outcomes showed that the LVIS stent group had a slightly higher complete occlusion rate and lower recurrence rate than the laser-cut stent group(92.7%vs 80.6%;3.7%vs 9.7%,P=0.078).The clinical outcomes at discharge and follow-up between the two groups demonstrated no significant differences(P=0.495 and P=0.875,respectively).The rates of intraprocedural thrombosis,postprocedural thrombosis,postoperative early rebleeding,and procedure-related death were 0.7%(1/142),1.4%(2/142),2.8%(4/142),and 2.1%(3/142)in the LVIS stent group,respectively,and 4.3%(4/93),2.2%(2/93),1.1%(1/93),and 3.2%(3/93)in the laser-cut stent group,respectively(P=0.082,0.649,0.651,and 0.683).Nevertheless,the rates of overall procedure-related complications and intraprocedural rupture in the LVIS stent group were significantly lower than those in the laser-cut stent group(5.6%vs 14.0%,P=0.028;0.7%vs 6.5%,P=0.016).Multivariate analysis showed that laser-cut stent-assisted coiling was an independent predictor for overall procedurerelated complications(OR=2.727,P=0.037);a history of diabetes(OR=7.275,P=0.027)and other cerebrovascular diseases(OR=8.083,P=0.022)were independent predictors for ischemic complications,whereas none of the factors were predictors for hemorrhagic complications.Conclusions:Compared with laser-cut stent-assisted coiling,LVIS stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms could reduce the rates of overall procedure-related complications and intraprocedural rupture.

Space-confined growth of monolayer ReSe2 under a graphene layer on Au foils

Vertical heterostructures based on two-dimensional(2D)materials have attracted widespread interest for their numerous applications in electronic and optoelectronic devices.Herein,we report the direct construct!on of an abnormal graphene/ReSe2 stack on Au foils by a two-step chemical vapor deposition(CVD)strategy.During the second growth stage,mono layer ReSe2 is found to prefere ntially evolve at the irUerface between the first-grown graphene layer and the Au substrate.The unusual stacking behavior is unraveled by in-situ"cutting open"the upper graphene from the defects to expose the lower ReSe2 using scanning tunneling microscopy(STM).From combination of these results with density functional theory calculations,the domain boundaries and edge sites of graphene are proposed to be adsorption sites for Re and Se precursors,further facilitating the growth of ReSe2 at the van der Waals gap of graphene/Au.This work hereby offers an intriguing strategy for obtaining vertical 2D heterostructures featured with an ultra-clean interface and a designed stacking geometry.

Scalable salt-templated directed synthesis of high-quality MoS_(2) nanosheets powders towards energetic and environmental applications

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)have emerged as perfect platforms for developing applications in nano-electronics,catalysis,energy storage and environmental-related fields due to their superior properties.However,the low-cost,batch production of high-quality 2D TMDCs remains a huge challenge with the existing synthetic strategies.Herein,we present a scalable chemical vapor deposition(CVD)approach for the batch production of high-quality MoS_(2) nanosheet powders,by using naturally abundant,water-soluble and recyclable NaCl crystal powders as templates.The high-quality MoS_(2) nanosheets powders are achieved by a facile water dissolution-filtration process,by virtue of the excellent dispersibility of the as-grown products in water.The internal mechanism for the scalable synthesis strategy is explored.The applications of the MoS_(2) nanosheets powders are also demonstrated as catalysts or adsorbents in hydrogen evolution reaction(HER)and organic dyes adsorption,respectively.This work should hereby pave ways for the mass production and application of powdery TMDCs in energetic and environmental related fields.

Salt-assisted growth and ultrafast photocarrier dynamics of large-sized monolayer ReSe2

Owing to its anisotropic optical and electrical properties,rhenium diselenide(ReSe2)has garnered considerable attention recently as a candidate material for polarization-sensitive photodetectors.However,the direct and controllable synthesis of large-sized ReSe2 with a uniform thickness is still a great challenge.Herein,we have refined the synthesis method to obtain uniform monolayer ReSe2 flakes with a size of up to^106μm on sapphire via an ambient-pressure chemical vapor deposition technique using Na promoter from sodium chloride.Interestingly,optical pump-probe spectroscopy revealed a fast switching from saturable absorption(SA)to absorption enhancement(AE)in subpicosecond time scale,followed by a slower decay induced by exciton recombination.Furthermore,both AE and SA signals exhibited clear angular dependence with a periodicity of 180°,which reflected the dichroism in nonlinear absorption dynamics.In addition,the photocarrier dynamics including free-carrier transport and subpicosecond relaxation due to exciton formation or surface trapping was probed using time resolved terahertz spectroscopy.We believe that our study serves as a reference for atomically controlled synthesis of large-sized ReSe2 and provides useful insights on its optoelectronic properties for novel device applications.

Oblique detonation wave triggered by a double wedge in hypersonic flow

Pressure-gain combustion has gained attention for airbreathing ramjet engine applications owing to its better thermodynamic efficiency and fuel consumption rate. In contrast with traditional detonation induced by a single wedge, the present study considers oblique shock interactions attached to double wedges in a hypersonic combustible flow. The temperature/pressure increases sharply across the interaction zone that initiates an exothermic reaction, finally resulting in an Oblique Detonation Wave(ODW). Compared with the case for a single-wedge ODW, the double-wedge geometry has great potential to control the initiation of the ODW. As a tentative study, two-dimensional compressible Euler equations with a two-step induction-reaction kinetic model are used to solve the detonation dynamics triggered by a double wedge. The effects of the wedge angles and wedge corner locations on the initiation structures are investigated numerically.The results show an ODW complex comprising three Oblique Shock Waves(OSWs), an induction zone, a curved detonation front, and an unburned/low-temperature gas belt close to the surface of the second wedge. Both the increasing wedge angle and downstream wedge corner location lead to an abrupt OSW–ODW transition type, whereas the former corresponds to the shock–shock interaction and the later has a greater effect on the exothermic chemical process. Analysis of the shock polar and flow scale confirms that the OSW–ODW initiation structure mainly depends on the coupling of shocks and heat release in a confined initiation zone.

The biology of bone morphogenetic protein signaling pathway in cerebrovascular system

Bone morphogenetic protein belongs to transcription growth factor superfamilyβ;bone morphogenetic protein signal pathway regulates cell proliferation,differentiation,and apoptosis among different tissues.Cerebrovascular system supplies sufficient oxygen and blood into brain to maintain its normal function.The disorder of cerebrovascular system will result into serious cerebrovascular diseases,which is gradually becoming a major threat to human health in modern society.In recent decades,many studies have revealed the underlying biology and mechanism of bone morphogenetic protein signal pathway played in cerebrovascular system.This review will discuss the relationship between the two aspects,aiming to provide new perspective for non-invasive treatment and basic research of cerebrovascular diseases.