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Science China Chemistry 2024年第2期67卷 558-567页

作者： Shan-Shan Li Yu-Shi Jiang xue-Ling Luo Xuming Ran Yuqiang Li Dong Wu cheng-xue pan Peng-Ju Xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China Shanghai Artificial Intelligence Laboratory Shanghai200433China The Institute for Advanced Studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer catalysis.The reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated manner.The strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and anti-stereoselectivity.Through the utilization of a combination of experimental techniques and density functional theory(DFT),we delved deeper into the mechanistic intricacies of this distinctive system.Results revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl radicals.This discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling DFT studies regio-and anti-stereoselectivity multisubstituted alkenes

A Time-Domain Numerical Simulation for Free Motion Responses of Two Ships Advancing in Head Waves

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China Ocean Engineering 2024年第3期38卷 519-530页

作者： pan Su-yong cheng Yong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The constant panel method within the framework of potential flow theory in the time domain is developed for solving the hydrodynamic interactions between two parallel ships with forward speed.When solving problems within a time domain framework,the free water surface needs to simultaneously satisfy both the kinematic and dynamic boundary conditions of the free water surface.This provides conditions for adding artificial damping layers.Using the Runge−Kutta method to solve equations related to time.An upwind differential scheme is used in the present method to deal with the convection terms on the free surface to prevent waves upstream.Through the comparison with the available experimental data and other numerical methods,the present method is proved to have good mesh convergence,and satisfactory results can be obtained.The constant panel method is applied to calculate the hydrodynamic interaction responses of two parallel ships advancing in head waves.Numerical simulations are conducted on the effects of forward speed,different longitudinal and lateral distances on the motion response of two modified Wigley ships in head waves.Then further investigations are conducted on the effects of different ship types on the motion response.

关键词： ship motions time domain simulation forward speed different distances wave loads

Channel Estimation for Reconfigurable Intelligent Surface Aided Multiuser Millimeter-Wave/THz Systems

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China Communications 2024年第3期21卷 91-103页

作者： Chu Hongyun pan xue Li Baijiang School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

It is assumed that reconfigurable intelligent surface(RIS)is a key technology to enable the potential of mmWave communications.The passivity of the RIS makes channel estimation difficult because the channel can only be measured at the transceiver and not at the RIS.In this paper,we propose a novel separate channel estimator via exploiting the cascaded sparsity in the continuously valued angular domain of the cascaded channel for the RIS-enabled millimeter-wave/Tera-Hz systems,i.e.,the two-stage estimation method where the cascaded channel is separated into the base station(BS)-RIS and the RIS-user(UE)ones.Specifically,we first reveal the cascaded sparsity,i.e.,the sparsity exists in the hybrid angular domains of BS-RIS and the RIS-UEs separated channels,to construct the specific sparsity structure for RIS enabled multi-user systems.Then,we formulate the channel estimation problem using atomic norm minimization(ANM)to enhance the proposed sparsity structure in the continuous angular domains,where a low-complexity channel estimator via Alternating Direction Method of Multipliers(ADMM)is proposed.Simulation findings demonstrate that the proposed channel estimator outperforms the current state-of-the-arts in terms of performance.

关键词： atomic norm minimization cascaded channel estimation convex optimization mmWave/THz reconfigurable intelligent surface(RIS) sparsity

Top Five Stories of the Cellular Landscape and Therapies of Atherosclerosis:Current Knowledge and Future Perspectives

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Current Medical Science 2024年第1期44卷 1-27页

作者： Qi pan cheng CHEN Yue-jin YANG State Key Laboratory of Cardiovascular Disease Department of CardiologyFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100037China

Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional cellular paradigm.However,the mechanisms appear much more complicated than we thought since a bulk of studies on efferocytosis,transdifferentiation and novel cell death forms such as ferroptosis,pyroptosis,and extracellular trap were reported.Discovery of novel pathological cellular landscapes provides a large number of therapeutic targets.On the other side,the unsatisfactory therapeutic effects of current treatment with lipid-lowering drugs as the cornerstone also restricts the efforts to reduce global AS burden.Stem cell-or nanoparticle-based strategies spurred a lot of attention due to the attractive therapeutic effects and minimized adverse effects.Given the complexity of pathological changes of AS,attempts to develop an almighty medicine based on single mechanisms could be theoretically challenging.In this review,the top stories in the cellular landscapes during the initiation and progression of AS and the therapies were summarized in an integrated perspective to facilitate efforts to develop a multi-targets strategy and fill the gap between mechanism research and clinical translation.The future challenges and improvements were also discussed.

关键词： atherosclerosis transdifferentiation extracellular traps efferocytosis stem cell nanoparticles

Deep insight of unique phase transition behaviors and mechanism in Zr_(2)Co-H isotope system with ultra-low equilibrium pressure

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Rare Metals 2024年第1期43卷 212-224页

作者： Yang Liu pan-pan Zhou xue-Zhang Xiao Jia-cheng Qi Jia-Peng Bi Tiao Ying Xing-Wen Feng Yan Shi Wen-Hua Luo Li-Xin Chen State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Institute of Materials China Academy of Engineering PhysicsMianyang 621907China Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province Hangzhou 310013China

Efficient capture,safe storage and release of tritium from the international thermonuclear experimental reactor(ITER) reaction exhaust gas is a perplexing problem,and the development of an efficient tritium-getter material with ultra-low hydrogenation equilibrium pressure is considered as a reliable way.In this work,Zr_(2)Co alloy was selected as a tritium-getter material and prepared through induction levitation melting.Fundamental performance test results show that Zr_(2)Co exhibits an ultra-low hydrogenation equilibrium pressure of 3.22 × 10^(-6) Pa at 25℃ and excellent hydriding kinetics under a low hydrogen pressure of 0.005 MPa.Interestingly,unique phase transition behaviors were presented in Zr_(2)Co-H system.Specifically,Zr_(2)CoH_(5) formed by Zr_(2)Co hydrogenated at room temperature is initially decomposed into ZrH_(2) and ZrCoH_(3) at200 ℃.With the temperature increasing to 350 ℃,ZrCoH_(3)is dehydrogenated to ZrCo,and then ZrCo further reacts with ZrH_(2) at 650 ℃ to reform Zr_(2)Co and hydrogen.Among the staged phase transition pathways during dehydrogenation,the decomposition of Zr_(2)CoH_(5) occurs preferentially,which is well accordance with both the smallest reaction energy barrier and the maximum reaction spontaneity that are determined respectively from kinetics activation energy and thermodynamics Gibbs free energy.Furthermore,first principles calculation results indicate that the stronger binding of hydrogen in interstitial environments of ZrCoH_(3)and ZrH_(2) triggers the hydrogen-stabilized phase transformation of Zr_(2)CoH_(5).The unique phase transition mechanisms in Zr_(2)Co-H system can shed light on the further exploration and regulation of analogous staged phase transition of hydrogen storage materials.

关键词： Zr_(2)Co alloy Tritium-getter materials Ultralow equilibrium hydrogen pressure Phase transition mechanism

CD3ε of a pan T cell marker involved in mouse Aspergillus fumigatus keratitis

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 616-624页

作者： Wen-Hao Shi Li-Mei Wang Hai-Jing Yan Shi-Long Liu Xian Yang xue-JiaoYang cheng-Ye Che Department of Ophthalmology the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina Weifang Medical University Weifang 261053Shandong ProvinceChina Eye Hospital of Wenzhou Medical University Wenzhou 325027Zhejiang ProvinceChina Department of Medical Engineering the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

AIM:To explore whether CD3ε is involved in the adaptive immunity of Aspergillus fumigatus(A.fumigatus)keratitis in mice and the role of innate and adaptive immunity in it.METHODS:Mice models of A.fumigatus keratitis were established by intra-stromal injection and corneal epithelial scratching.Subconjunctival injections of natamycin,wedelolactone,LOX-1 inhibitor(poly I)or Dectin-1 inhibitor(laminarin)were used to treat mice with A.fumigatus keratitis.Mice were pretreated by intraperitoneal injection of anti-mouse CD3ε.We observed the corneal infection of mice under the slit lamp microscope and made a clinical score.The protein expression of CD3ε and interleukin-10(IL-10)was determined by Western blotting.RESULTS:With the disease progresses,the degree of corneal opacity and edema augmented.In the intrastromal injection models,CD3εprotein expression began to increase significantly on the 2^(nd) day.However,in the scraping epithelial method models,CD3ε only began to increase on the 3^(rd) day.After natamycin treatment,the degree of corneal inflammation in mice was significantly attenuated on the 3^(rd) day.After wedelolactone treatment,the severity of keratitis worsened.And the amount of CD3ε protein was also reduced,compared with the control group.By inhibiting LOX-1 and Dectin-1,there was no significant difference in CD3ε production compared with the control group.After inhibiting CD3ε,corneal ulcer area and clinical score increased,and IL-10 expression was downregulated.CONCLUSION:As a pan T cell marker,CD3ε participate in the adaptive immunity of A.fumigatus keratitis in mice.In our mice models,the corneas will enter the adaptive immune stage faster.By regulating IL-10,CD3ε exerts antiinflammatory and repairs effects in the adaptive immune stage.

关键词： CD3ε adaptive immunity Aspergillus fumigatus keratitis interleukin-10

Significant contribution of carbonyls to atmospheric oxidation capacity(AOC)during the winter haze pollution over North China Plain

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Journal of Environmental Sciences 2024年第5期139卷 377-388页

作者： xue Yang Gen Zhang Guang pan Guolan Fan Houyong Zhang Xuan Ge Mingyue Du School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China Shandong Jinan Ecological Environment Monitoring Center Ji’nan 250101China

Atmospheric carbonyl compounds play significant roles in the cycling of radicals and have exhibited surprisingly high levels in winter that were well correlated to particulate matter,for which the reason have not been clearly elucidated.Here we measured carbonyl compounds and other trace gasses together with PM_(2.5)over urban Jinan in North China Plain during the winter.Markedly higher carbonyl concentrations(average:14.63±4.21 ppbv)were found during wintertime haze pollution,about one to three-times relative to those on nonhaze days,with slight difference in chemical composition except formaldehyde(HCHO).HCHO(3.68 ppbv),acetone(3.17 ppbv),and acetaldehyde(CH_3CHO)(2.83 ppbv)were the three most abundant species,accounting for~75% of the total carbonylson both haze and non-haze days.Results from observational-based model(OBM)with atmospheric oxidation capacity(AOC)indicated that AOC significantly increased with the increasing carbonyls during the winter haze events.Carbonyl photolysis have supplied key oxidants such as RO_(2) and HO_(2),and thereby enhancing the formation of fine particles and secondary organic aerosols,elucidating the observed haze-carbonyls inter-correlation.Diurnal variation with carbonyls exhibiting peak values at early-noon and night highlighted the combined contribution of both secondary formation and primary diesel-fuel sources.1-butene was further confirmed to be the major precursor for HCHO.This study confirms the great contribution of carbonyls to AOC,and also suggests that reducing the emissions of carbonyls would be an effective way to mitigate haze pollution in urban area of the NCP region.

关键词： Carbonyls Haze Observation-based model Source apportionment Atmospheric oxidation capacity

Shape optimisation of basin insulator for DC gas insulated switchgear/gas insulated transmission lines based on artificial bee colony algorithm

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High Voltage 2024年第2期9卷 275-286页

作者： Yi Luo Shiyi Mao Ju Tang Zijun pan cheng pan State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

The surface charge accumulation on the basin insulator is a particular problem in high-voltage direct current(HVDC)gas insulated switchgears(GIS)and gas insulated trans-mission lines(GIL),which restricts the development and application of extra/ultra high-voltage(EHV/UHV)technology.The surface charge distribution and anti-flashover performance are closely related to the insulator shape.To obtain the optimal basin insulator,a shape optimisation model based on artificial bee colony algorithm was established,and the minimisation objective functions based on capacitive(initial)electric field distribution and resistive(steady-state)electric field distribution were respectively constructed.The optimisation results of the two objective functions were calculated,and the electric field and charge distribution on the surface of the insulator before and after optimisation were evaluated and compared using the simulation model.The results indicated that the optimisation based on the capacitive electric field can significantly inhibit the surface charge accumulation,and the optimised insulator can significantly reduce the surface normal electric field and make the distribution of the tangential electric field more uniform,and the maximum tangential electric field can be reduced by 10%;the optimisation based on resistive electric field can achieve similar results,but requires more computational resources.Based on the results,the‘anti-charge’basin insulator structure suitable for the DC field was given.

关键词： insulator artificial charge

Toughening additive manufactured Zr-based bulk metallic glass composites by martensite phase transformation

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Journal of Materials Science & Technology 2024年第3期170卷 95-102页

作者： Pengcheng Zhang cheng Zhang Jie pan Di Ouyang Lin Liu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Additive manufacturing technology based on laser powder bed fusion(LPBF)offers a novel approach for fabricating bulk metallic glass(BMG)products without restriction in size and geometry.Nevertheless,the BMGs prepared by LPBF usually suffered from less plasticity and poorer fracture toughness as compared to their cast counterparts due to partial crystallization in heat-affected zones(HAZs).Since crystallization in HAZs is hard to avoid completely in LPBF BMGs,it is desirable to design a suitable alloy system,in which only ductile crystalline phase,instead of brittle intermetallics,is formed in HAZs.This unique structure could effectively increase the toughness/plasticity of the LPBF BMGs.To achieve this goal,a quaternary BMG system with a composition of Zr_(47.5)Cu_(45.5)Al_(5)Co_(2)is adopted and subjected to LPBF.It is found that nearly a single phase of B_(2)-ZrCu is precipitated in HAZs,while a fully amorphous phase is formed in molten pools(MPs).This B_(2)phase reinforced BMG composite exhibits excellent mechanical properties with enhanced plasticity and toughness.Furthermore,it is easy to modulate the mechanical properties by altering the amount of the B_(2)phase via adjusting the laser energy input.Finally,the best combination of strength,plasticity,and notch toughness is obtained in the BMG composite containing 27.4%B_(2)phase and 72.6%amorphous phase,which exhibits yield strength(σ_(s))of 1423 MPa,plastic strain(ε_(p))of 4.65%,and notch toughness(K_(q))of 53.9 MPa m 1/2.Furthermore,a notable strain-hardening is also observed.The improvement of plasticity/toughness and appearance of strain-hardening behavior are mainly due to the martensite phase transformation from the B_(2)phase to the Cm phase during plastic deformation(i.e.,the phase transformation-induced plasticity effect).The current work provides a guide for making advanced BMGs and BMG composites by additive manufacturing.

关键词： Laser powder bed fusion Bulk metallic glass composites Phase transformation-induced plasticity Deformation mechanism

Dietary Macleaya cordata extract supplementation improves the growth performance and gut health of broiler chickens with necrotic enteritis

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Journal of Animal Science and Biotechnology 2024年第1期15卷 374-395页

作者： Bochen Song Jie He xue pan Linglian Kong Chuanpi Xiao Chake Keerqin Zhigang Song Key Laboratory of Efficient Utilization of Non‑Grain Feed Resources College of Animal Science and TechnologyShandong Agricultural UniversityTaian 271018ShandongChina Center for Mitochondria and Healthy Ageing College of Life SciencesYantai UniversityYantai 264005ShandongChina Precision Livestock and Nutrition Unit University of LiègeGembloux Agro‑Bio TechGemblouxBelgium Phytobiotics(Jiangsu)Biotech Co. Ltd.Jintan 213200China

Background The poultry industry needs effective antibiotic alternatives to control outbreaks of necrotic enteritis(NE)caused by Clostridium perfringens.Methods The aim of this study was to investigate the effects of dietary supplementation with Macleaya cordata extract(MCE)on the immune function and gut microbiota of broilers with NE.A total of 2881-day-old broiler chicks were randomly assigned to a 2×2 factorial arrangement with two concentrations of dietary MCE supplementation(0 or 350 mg/kg of diet)and two disease challenge statuses(control or NE).Results The results revealed that NE significantly increased the feed conversion rate(FCR),mortality,intestinal lesion score,the levels of IL-1β,IL-17 and IFN-γ/IL-4 in serum and IL-17/IL-10 in the jejunal mucosa,m RNA levels of TLR2,IFN-γand p Ig R in the jejunum,and Clostridium perfringens concentrations in the cecum.NE significantly decreased the body weight(BW),body weight gain(BWG),jejunal villus height,V/C,m RNA level of AMPK-α1 in jejunum,IL-4 level in the jejunal mucosa and lactic acid bacteria abundance in the cecum.MCE significantly increased BW,BWG,jejunal villus height,V/C,m RNA levels of occludin,ZO-1 and AMPK-α1 in the jejunum,the levels of Ig A and Ig G in serum and IL-10 in the jejunal mucosa and m RNA levels of NF-κB,IL-10 and MHC-II in the jejunum.Additionally,MCE significantly decreased the FCR,mortality,intestinal lesion score,jejunal crypt depth,the levels of IFN-γand IL-17 in serum and IL-17/IL-10 in the jejunal mucosa,Clostridium perfringens concentrations in the cecum,and m RNA levels of IL-17/IL-10 in the jejunum.Moreover,NE significantly increased the abundance of bacteria that are associated with inflammation,obesity and depression(Alistipes,Barnesiella,Intestinimonas,RF39 and UCG-005)and significantly decreased the abundance of short-chain fatty acid(SCFA)-producing bacteria(Anaerotruncus,Butyricicoccus and Bacteroides)in the cecum.MCE significantly increased the abundance of SCFA-producing bacteria(Streptococcus,Ruminococcus_torques_group

关键词： Broiler chicken Gut microbiota Immune function Macleaya cordata extract Necrotic enteritis