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1Pathogenic T-cells and inflammatory monocytes incite inflammatory storms in severe COVID-19 patients显示文摘Pathogenic human coronavirus infections,such as severe acute respiratory syndrome CoV(SARS-CoV)and Middle East respiratory syndrome CoV(MERS-CoV),cause high morbidity and mortality[1,2].Recently,a severe pneumonia-associated respiratory syndrome caused by a new coronavirus(SARS-CoV-2)was reported in December 2019 in the city of Wuhan,Hubei province,China[3-5],which was also named as pneumonia-associated respiratory syndrome(PARS)[6]and can cause coronavirus disease 2019(COVID-19)to seriously endanger human health.Yonggang Zhou Binqing Fu Xiaohu Zheng Dongsheng Wang Changcheng Zhao Yingjie Qi Rui Sun Zhigang Tian Xiaoling Xu Haiming Wei 2020National Science Review2020,7,6:54
2A 4-bp Insertion at ZmPLA 1 Encoding a Putative Phospholipase A Generates Haploid Induction in Maize显示文摘Chenxu Liu Xiang Li Dexuan Meng Yu Zhong Chen Chen Xin Dong Xiaowei Xu Baojian Chen Wei Li Liang Li Xiaolong Tian Haiming Zhao Weibin Song Haishan Luo Qinghua Zhang Jinsheng Lai Weiwei Jin Jianbing Yan Shaojiang Chen 2017Molecular Plant2017,10,3:39
3Immunotherapeutical Potential of Mycobacterium Vaccae on M. Tuberculosis Infection in Mice显示文摘Tuberculosis remains the worldwide infectious disease. To identify the therapeutic potential of M. vaccae in treating tuberculosis,M. vaccae was injected into Mycobacterium tuberculosis(M. tuberculosis) infected mice. The optimal dose of M. vaccae(22.5 μg/mouse) treated mice showed lower pathological change index,spleen weight index,lung weight index and vital M. tuberculosis count than those of the untreated group. Treatment with M. vaccae enhanced the percentages of CD3+ and CD4+ T cells,IFN-γ+CD4+ T cells,innate immune cells including NK cells,NK1.1+ T cells and γδ T cells,and reduced the percentage of IL-4+CD4+ T cells. Therefore,M. vaccae could protect the mice from M. tuberculosis infection and improved mouse innate and adaptive cell-mediated immunity,suggesting that M. vaccae is a potential immunotherapeutic agent in pulmonary tuberculosis.Lijun Xu Yanyan Wang Xiaodong Zheng Xiangdong Gui Lifeng Tao Haiming Wei 2009Cellular & Molecular Immunology2009,6,1:11
4Low-dose real-time X-ray imaging with nontoxic double perovskite scintillators显示文摘X-rays are widely used in probing inside information nondestructively,enabling broad applications in the medical radiography and electronic industries.X-ray imaging based on emerging lead halide perovskite scintillators has received extensive attention recently.However,the strong self-absorption,relatively low light yield and lead toxicity of these perovskites restrict their practical applications.Here,we report a series of nontoxic double-perovskite scintillators of Cs_(2)Ag_(0.6)Na_(0.4)In_(1-y)Bi_(y)Cl_(6).By controlling the content of the heavy atom Bi^(3+),the X-ray absorption coefficient,radiative emission efficiency,light yield and light decay were manipulated to maximise the scintillator performance.A light yield of up to 39,000±7000 photons/MeV for Cs_(2)Ag_(0.6)Na_(0.4)In_(0.85)Bi_(0.15)Cl_(6) was obtained,which is much higher than that for the previously reported lead halide perovskite colloidal CsPbBr_(3)(21,000 photons/MeV).The large Stokes shift between the radioluminescence(RL)and absorption spectra benefiting from self-trapped excitons(STEs)led to a negligible selfabsorption effect.Given the high light output and fast light decay of this scintillator,static X-ray imaging was attained under an extremely low dose of ∼1μGy_(air),and dynamic X-ray imaging of finger bending without a ghosting effect was demonstrated under a low-dose rate of 47.2μGy_(air) s^(−1).After thermal treatment at 85℃ for 50 h followed by X-ray irradiation for 50 h in ambient air,the scintillator performance in terms of the RL intensity and X-ray image quality remained almost unchanged.Our results shed light on exploring highly competitive scintillators beyond the scope of lead halide perovskites,not only for avoiding toxicity but also for better performance.Wenjuan Zhu Wenbo Ma Yirong Su Zeng Chen Xinya Chen Yaoguang Ma Lizhong Bai Wenge Xiao Tianyu Liu Haiming Zhu Xiaofeng Liu Huafeng Liu Xu Liu Yang(Michael)Yang 2020Light(Science & Applications)2020,9,1:9
5Theoretical prediction,synthesis,and crystal structure determination of new MAX phase compound V2SnC显示文摘Guided by the theoretical prediction,a new MAX phase V2SnC was synthesized experimentally for the first time by reaction of V,Sn,and C mixtures at 1000°C.The chemical composition and crystal structure of this new compound were identified by the cross-check combination of first-principles calculations,X-ray diffraction(XRD),energy dispersive X-ray spectroscopy(EDS),and high resolution scanning transmission electron microscopy(HR-STEM).The stacking sequence of V2C and Sn layers results in a crystal structure of space group P63/mmc.The a-and c-lattice parameters,which were determined by the Rietveld analysis of powder XRD pattern,are 0.2981(0)nm and 1.3470(6)nm,respectively.The atomic positions are V at 4f(1/3,2/3,0.0776(5)),Sn at 2d(2/3,1/3,1/4),and C at 2a(0,0,0).A new set of XRD data of V2SnC was also obtained.Theoretical calculations suggest that this new compound is stable with negative formation energy and formation enthalpy,satisfied Born-Huang criteria of mechanical stability,and positive phonon branches over the Brillouin zone.It also has low shear deformation resistance c44(second-order elastic constant,cij)and shear modulus(G),positive Cauchy pressure,and low Pugh’s ratio(G/B=0.500<0.571),which is regarded as a quasi-ductile MAX phase.The mechanism underpinning the quasi-ductility is associated with the presence of a metallic bond.Qiang Xu Yanchun Zhou Haiming Zhang Anna Jiang Quanzheng Tao Jun Lu Johanna Rosén Yunhui Niu Salvatore Grasso Chunfeng Hu 2020Journal of Advanced Ceramics2020,9,4:8
6Gentiopicroside targets PAQR3 to activate the PI3K/AKT signaling pathway and ameliorate disordered glucose and lipid metabolism显示文摘The obstruction of post-insulin receptor signaling is the main mechanism of insulin-resistant diabetes.Progestin and adipoQ receptor 3(PAQR3),a key regulator of inflammation and metabolism,can negatively regulate the PI3 K/AKT signaling pathway.Here,we report that gentiopicroside(GPS),the main bioactive secoiridoid glycoside of Gentiana manshurica Kitagawa,decreased lipid synthesis and increased glucose utilization in palmitic acid(PA) treated HepG2 cells.Additionally,GPS improved glycolipid metabolism in streptozotocin(STZ) treated high-fat diet(HFD)-induced diabetic mice.Our findings revealed that GPS promoted the activation of the PI3 K/AKT axis by facilitating DNA-binding protein 2(DDB2)-mediated PAQR3 ubiquitinated degradation.Moreover,results of surface plasmon resonance(SPR),microscale thermophoresis(MST) and thermal shift assay(TSA) indicated that GPS directly binds to PAQR3.Results of molecular docking and cellular thermal shift assay(CETSA) revealed that GPS directly bound to the amino acids of the PAQR3 NH2-terminus including Leu40,Asp42,Glu69,Tyr125 and Ser129,and spatially inhibited the interaction between PAQR3 and the PI3 K catalytic subunit(P110α) to restore the PI3 K/AKT signaling pathway.In summary,our study identified GPS,which inhibits PAQR3 expression and directly targets PAQR3 to restore insulin signaling pathway,as a potential drug candidate for the treatment of diabetes.Haiming Xiao Xiaohong Sun Zeyuan Lin Yan Yang Meng Zhang Zhanchi Xu Peiqing Liu Zhongqiu Liu Heqing Huang 2022Acta Pharmaceutica Sinica B2022,12,6:7
7Prehistoric agriculture development in the Yunnan-Guizhou Plateau, southwest China: Archaeobotanical evidence显示文摘The origin, development and expansion of prehistoric agriculture in East Asia have been widely investigated over the past two decades using archaeobotanical analysis from excavated Neolithic and Bronze Age sites. Research on prehistoric agriculture has predominantly focused in the valleys of the Yellow River and the Yangtze River. Agricultural development during the Neolithic and Bronze Age periods in the Yunnan-Guizhou Plateau of southwest China, an important passageway for human migration into Southeast Asia, still remains unclear. In this paper, based on macrofossil and microfossil analysis and radiocarbon dating at the Shilinggang site, we investigate plant subsistence strategies in the Nujiang River valley during the Bronze Age period. Combined with previous archaeobotanical studies in the Yunnan-Guizhou Plateau, we explore agricultural development processes in this area during the Neolithic and Bronze Age. Our results indicate that rice and foxtail millet were cultivated in Shilinggang around 2500 cal a BP. Three phases of prehistoric agricultural development in the Yunnan-Guizhou Plateau can be identified: rice cultivation from 4800–3900 cal a BP, mixed rice and millet crop(foxtail millet and broomcorn millet) cultivation from 3900–3400 cal a BP, and mixed rice, millet crop and wheat cultivation from 3400–2300 cal a BP. The development of agriculture in the Yunnan-Guizhou Plateau during the Neolithic and Bronze Age periods was primarily promoted by prehistoric agriculture expansion across Eurasia, agricultural expansion which was also affected by the topographic and hydrological characteristics of the area.LI HaiMing ZUO XinXin KANG LiHong REN LeLe LIU FengWen LIU HongGao ZHANG NaiMeng MIN Rui LIU Xu DONG GuangHui 2016Science China Earth Sciences2016,59,8:6
8Nonlinear quantum interferometry with Bose condensed atoms显示文摘在量 interferometry,为高精确的大小的成就控制并且利用非线性的相互作用是重要的。由于他们的长连贯时间和高可控制性,包括 Bose 的 ultracold 原子压缩了原子广泛地为量 interferometry 被使用了。这里,我们与 Bose 在量 interferometry 的理论研究考察最近的进步压缩原子。特别地,我们集中于原子原子相互作用导致的非线性的现象,并且怎么控制并且利用这些非线性的现象。与吝啬地的描述,由于原子原子相互作用,事波浪 solitons 出现在干扰模式,和宏观的量自我套住在 Bose-Josephson 连接存在。与许多身体描述,原子原子相互作用能产生非古典的纠纷,它能被利用在标准量限制以外完成高精确的大小。Chaohong Lee (1) Jiahao Huang (1) Haiming Deng (1) Hui Dai (1) Jun Xu (1) 2012Frontiers of physics2012,7,1:6
9Artificial periosteum in bone defect repair--A review显示文摘Periosteum is a thin membrane that encases the surfaces of most bones.It is composed of an outer fibrous layer contains longitudinally oriented cells and collagen fibers and an inner cambial layer that consists of multipotent mesenchymal stem cells(MSCs)and osteogenic progenitor cells.Periosteum has a function of regulating cell and collagen arrangement,which is important to the integrity,modelling and remodelling of bone,particularly during bone defect repair.Apart from autograft and allograft,artificial periosteum,or tissue-engineered periosteum mimicking native periosteum in structure or function,made up of small intestinal submucosa,acellular dermis,induced membrane,cell sheets,and polymeric scaffolds,and so on,has been developed to be used in bone defect repair.In this review,we classify the artificial periosteum into three approaches based on the material source,that is,native tissues,scaffoldfree cell sheets and scaffold-cell composites.Mechanisms,methods and efficacy of each approach are provided.Existing obstacles and enabling technologies for future directions are also discussed.Quan Wang Jianxiang Xu Haiming Jin Wenhao Zheng Xiaolei Zhang Yixing Huang Zhiyong Qian 2017Chinese Chemical Letters2017,28,9:6
10Discrimination for ablative control mechanism in solid-propellant rocket nozzle显示文摘The ablation in solid-propellant rocket nozzle is a coupling process resulted by chemistry, heat and mass transfer. Based on the heat and mass transfer theory, the aero-thermo-dynamic, and thermo-chemical kinetics, the thermal-chemical ablation model is established. Simulations are completed on the heat flow field and chemical ablation in the nozzle with different concentrations, frequency factors and activation energy of H2. The calculation results show that the concentration and the activation energy of H2 can provoke the transformation of control mechanism, whereas the influence brought by the frequency factor of H2 is feeble under a high-temperature and high-pressure combustion circumstance. The discrimination for ablative control mechanism is dependent on both concentration and activation energy of H2. This study will be useful in handling ablation and thermal protection problem in the design of solid-propellant rocket.HUANG HaiMing XU XiaoLiang JIANG GuiQing 2009Science China(Technological Sciences)2009,52,10:6
11Cartilage-targeting peptide-modified dual-drug delivery nanoplatform with NIR laser response for osteoarthritis therapy显示文摘Cartilage-targeting delivery of therapeutic agents is still an effective strategy for osteoarthritis(OA)therapy.Recently,scavenging for reactive oxygen species(ROS)and activating autophagy have been increasingly reported to treat OA effectively.In this study,we designed,for the first time,a dual-drug delivery system based on metal organic framework(MOF)-decorated mesoporous polydopamine(MPDA)which composed of rapamycin(Rap)loaded into the mesopores and bilirubin(Br)loaded onto the shell of MOF.The collagen II-targeting peptide(WYRGRL)was then conjugated on the surface of above nanocarrier to develop a cartilage-targeting dual-drug delivery nanoplatform(RB@MPMW).Our results indicated the sequential release of two agents from RB@MPMW could be achieved via near-infrared(NIR)laser irritation.Briefly,the rapid release of Br from the MOF shell exhibited excellent ROS scavenging ability and anti-apoptosis effects,however responsively reduced autophagy activity,to a certain extent.Meanwhile,following the NIR irradiation,Rap was rapidly released from MPDA core and further enhanced autophagy activation and chondrocyte protection.RB@MPMW continuously phosphorylated AMPK and further rescued mitochondrial energy metabolism of chondrocytes following IL-1βstimulation via activating SIRT1-PGC-1αsignaling pathway.Additionally,the cartilage-targeting property of peptide-modified nanocarrier could be monitored via Magnetic Resonance(MR)and IVIS imaging.More significantly,RB@MPMW effectively delayed cartilage degeneration in ACLT rat model.Overall,our findings indicated that the as-prepared dual-drug delivery nanoplatform exerted potent anti-inflammation and anti-apoptotic effects,rescued energy metabolism of chondrocytes in vitro and prevented cartilage degeneration in vivo,which thereby showed positive performance for OA therapy.Song Xue Xiaojun Zhou Weilin Sang Cong Wang Haiming Lu Yiming Xu Yiming Zhong Libo Zhu Chuanglong He Jinzhong Ma 2021Bioactive Materials2021,6,8:5
12High Expression of NKG2A/CD94 and Low Expression of Granzyme B Are Associated with Reduced Cord Blood NK Cell Activity显示文摘Human umbilical cord blood (CB) has recently been used as a source of stem cells in transplantation. NK cells derived from CB are the key effector cells involved in graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL). It was reported that the activity of CB NK cells was lower than that of adult peripheral blood (PB) NK cells. In this study,we analyzed the expression of some NK cell receptors and cytotoxicity-related molecules in CB and PB NK cells. The expressions of activating NK receptors,CD16,NKG2D and NKp46,did not show significant difference between CB and PB NK cells. But the expression of inhibitory receptor NKG2A/CD94 was significantly higher on CB NK cells. As to the effector function molecules,granzyme B was expressed significantly lower in CB NK cells,but the expressions of intracellular perforin,IFN-γ,TNF-α and cell surface FasL and TRAIL did not show difference between CB and PB NK cells. The results indicated that the high expression of NKG2A/CD94 and low expression of granzyme B may be related with the reduced activity of CB NK cells.Yanyan Wang1,2,Han Xu1,2,Xiaodong Zheng1,Haiming Wei1,Rui Sun1 and Zhigang Tian1,31Institute of Immunology,Hefei National Laboratory for Physical Materials at Microscale and School of Life Sciences,University of Science and Technology of China,Hefei 230027,China 2Yanyan Wang and Han Xu equally contributed to the present study 2007Cellular & Molecular Immunology2007,4,5:5
13Observed oceanic feedback to the atmosphere over the Kuroshio Extension during spring time and its possible mechanism显示文摘High-resolution satellite measurements are used to study the air-sea interaction over the Kuroshio Extension (KE) region during spring time. There are two oceanic fronts in the KE region off the east coast of Japan. These fronts are generally associated with strong ocean currents, which may display unstable meander, resulting in remarkable warm sea surface temperature (SST) ridges and cold SST troughs. Analyses of these satellite observations reveal a significantly positive correlation between sea surface wind speed and its underlying SST along these fronts. This positive SST-wind correlation be-comes even more significant when strong meanders occur along the fronts. This positive SST-wind correlation indicates an ocean-to-atmosphere feedback over the KE region during spring time. A high-resolution regional atmospheric model is used to investigate the atmospheric response to SST changes along the two fronts.XU HaiMing WANG LinWei HE JinHai 2008Chinese Science Bulletin2008,53,12:5
14Geochemistry of Pyrite from the Gangcha Gold Deposit, West Qinling Orogen, China: Implications for Ore Genesis显示文摘The Gangcha gold deposit was discovered in 2011 in the Xiahe-Hezuo region, West Qinling Orogen, China. Five types of pyrite have been identified in the ore according to the detailed mineral paragenetic studies. Geochemical data are presented for type I pyrite(py1) rim-core zonation and for the different types of pyrite based on in-situ laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) and electron probe microanalysis(EPMA). The results show that pyrites are characterized with heterogeneous Au concentrations, which indicate that Au occurs mainly as micro-or nano-particle native inclusions. Time-resolved depth profiles demonstrate that As, Co and Ni occur as solid solutions in pyrite, whereas Cu, Pb, Zn and Ag occur mainly as inclusions. Trace element concentrations differ between rims and cores in py1, and the differences also exist within different pyrite types. These differences indicate complex chemical evolution of the ore-forming fluids, and the overall geology, geochronology, and stable isotope and pyrite data suggest that the ore-forming fluids were closely linked to magmatic activity during the Triassic Period in West Qinling orogenic belt.NIE Xiao SHEN Junfeng LIU Haiming DU Baisong WANG Shuhao LI Jie XU Liwei WANG Ran 2017Acta Geologica Sinica(English Edition)2017,91,6:5
15Polybrominated diphenyl ether (PBDE) in blood from children (age 9–12) in Taizhou, China显示文摘Polybrominated diphenyl ethers (PBDEs) as ubiquitous persistent organic pollutants have attracted much attention in recent years. Exposure to PBDEs could induce a high health risk for children. The aim of this study was to investigate the PBDEs exposure of children (9–12 years) from Taizhou, China. Fifty-eight blood samples were collected in one school in a mountainous area in Taizhou. The concentrations of ∑9PBDEs (sum of BDE-28, -47, -99, -100, -153, -154, -183, -197 and -209) ranged from 2.66 to 33.9 ng/g lipid wet (lw) with a median of 7.22 ng/g lw. These concentrations were lower than those of children in USA, but close to European and Asian general population levels. The results showed that children in Taizhou countryside were at a low level of PBDEs exposure. The predominant congener was BDE-209, followed by BDE-28, -47, -197 and -153. High abundance of BDE-209 was consistent with the pollution background of PBDEs in China characterized by high brominated congeners as main pollutants.Xiaoyou Zhang Xianli Ruan Minchan Yan Yaxian Zhao Wuji Wei Zhanfen Qin Yongjian Yang Haiming Xu Yan Li 2011Journal of Environmental Sciences2011,23,7:5
16Gas stunning with CO_2 affected meat color,lipid peroxidation, oxidative stress, and gene expression of mitogen-activated protein kinases, glutathione S-transferases,and Cu/Zn-superoxide dismutase in the skeletal muscles of broilers显示文摘Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the effect and mechanism of CO_2 stunning on meat color and lipid peroxidation during long-term storage remain poorly studied. We aimed to study the effects of GS methods, especial y CO_2 concentration, on meat color and meat lipid peroxidation in broilers during long-term storage at 4 °C and to explore the potential mechanism of meat color change via lipid peroxidation and the inner lipid peroxide scavenging system.Methods: Eighteen broilers were sacrificed after exposure to one of the following gas mixtures for 90 s: 40% CO_2+21% O_2+ 39% N2(G40%), 79% CO_2+ 21% O_2(G79%), or no stunning(0% CO_2, control). Meat color, serum variables,enzyme activities, and the gene expression of mitogen-activated protein kinase(MAPK), nuclear factor-erythroid2-related factor 2(Nrf2), glutathione S-transferase(GST) and superoxide dismutase(SOD) were determined.(Continued on next page)Results: The concentrations of serum triiodothyronine(T3, P = 0.03) and the ratio of serum free triiodothyronine/free thyroxine(FT3/FT4, P < 0.01) were decreased, whereas levels of serum cortisol(P < 0.01) were increased in the 40%CO_2 group compared with the control group. Additionally, the thiobarbituric acid-reactive substances(TBARS)3 d(P < 0.01) and TBARS6 d(P = 0.01) in breast meat and the TBARS3 din thigh meat(P < 0.01) were increased in the40% CO_2 group compared with the control group. Serum T3 was negatively correlated with TBARS6 dboth in the breast and thigh meat(r =-0.63, P < 0.01 and r =-0.47, P = 0.05 respectively). T3/T4 was negatively correlated with TBARS6 din the breast meat and in the thigh meat(r =-0.57, P = 0.01; and r =-0.53, P = 0.03 respectively). Compared with the control group, Lightness(L*)1 d(P = 0.03) and L*9 d(P < 0.01) were increased, whereas total chromatic aberration(E*)1 d(P = 0.05) and E*3 d(P < 0.01) were decreased in the breast meat of both the G40% and G79% groups. The values of yel owness(b*)3 d(P = 0.01), b*6 d(P < 0.01) and E*6 d(P < 0.01) in the thigh meat were lower in both the G40% and G79% groups than in the control group. In the breast muscle, the m RNA levels of c-Jun N-terminal kinase 2(JNK2, P = 0.03),GSTT1(P = 0.04), and SOD1(P = 0.05) were decreased, and the m RNA levels of JNK1(P = 0.07), Nrf2(P = 0.09), and GSTA3(P = 0.06) were slightly lower in both the G40% and G79% groups compared with the control group. However, among these genes, only the m RNA level of JNK1 was decreased in the G40% group compared with the control group and the G79% group(P = 0.03) in the thigh muscle.Conclusions: Compared with the control group, meat color quality in the breast meat was decreased, and the expression of genes in the MAPK/Nrf2/ARE(antioxidant responsive element) antioxidant pathway in breast muscle was partly suppressed by GS of both 40% and 79% CO_2. However, oxidative stress and meat lipid peroxidation during storage were aggravated by GS with 40% CO_2 compared to GS with 79% CO_2 and no GS.Lei Xu Haijun Zhang Hongyuan Yue Shugeng Wu Haiming Yang Zhiyue Wang Guanghai Qi 2018Journal of Animal Science and Biotechnology2018,9,3:5
17The boreal spring stratospheric final warming and its interannual and interdecadal variability显示文摘Based on the daily NCEP/DOE reanalysis II data,dates of the boreal spring Stratospheric Final Warming(SFW) events during 1979–2010 are defined as the time when the zonal-mean zonal wind at the central latitudes(65°–75°N) of the westerly polar jet drops below zero and never recovers until the subsequent autumn.It is found that the SFW events occur successively from the mid to the lower stratosphere and averagely from the mid to late April with a temporal lag of about 13 days from 10 to 50 hPa.Over the past 32 years,the earliest SFW occurs in mid March whereas the latest SFW happens in late May,showing a clear interannual variability of the time of SFW.Accompanying the SFW onset,the stratospheric circulation transits from a winter dynamical regime to a summertime state,and the maximum negative tendency of zonal wind and the strongest convergence of planetary-wave are observed.Composite results show that the early/late SFW events in boreal spring correspond to a quicker/slower transition of the stratospheric circulation,with the zonal-mean zonal wind reducing about 20/5 m s-1 at 30 hPa within 10 days around the onset date.Meanwhile,the planetary wave activities are relatively strong/weak associating with an out-of-/in-phase circumpolar circulation anomaly before and after the SFW events in the stratosphere.All these results indicate that,the earlier breakdown of the stratospheric polar vortex(SPV),as for the winter stratospheric sudden warming(SSW) events is driven mainly by wave forcing;and in contrast,the later breakdown of the SPV exhibits more characteristics of its seasonal evolution.Nevertheless,after the breakdown of SPV,the polar temperature anomalies always exhibit an out-of-phase relationship between the stratosphere and the troposphere for both the early and late SFW events,which implies an intimate stratosphere–troposphere dynamical coupling in spring.In addition,there exists a remarkable interdecadal change of the onset time of SFW in the mid 1990s.On average,the SFW onset time before the mid 1990s is 11 days earlier than that afterwards,corresponding to the increased/decreased planetary wave activities in late winter-early spring before/after the 1990s.HU JingGao REN RongCai YU YueYue XU HaiMing 2014Science China Earth Sciences2014,57,4:4
18Enhanced ozonation degradation of atrazine in the presence of nano-ZnO: Performance, kinetics and effects显示文摘Enhanced ozonation degradation of atrazine(ATZ) with nano-ZnO(nZnO) as catalyst and the influences of the operational parameters have been investigated through semi-continuous experiments in this study. The results demonstrated that the combination of ozone(O_3) and nZnO showed an obvious synergetic effect and the ATZ degradation conformed to pseudo-first-order kinetics. An improvement of ATZ degradation efficiency by 41.8% and pseudo-first-order rate constant by more than a factor of four was obtained in the O_3/nZnO process after 5 min of reaction compared to O_3 alone. Meanwhile, the degradation efficiency of ATZ was gradually enhanced with increasing nZnO dosage and initial pH in the range from 3.0 to 8.0, and a higher amount of ATZ was degraded when the initial concentration of ATZ rose from 0.5 to 5 mg/L. Additionally, sulfate ion, chloride ion, nitrate ion and low concentrations of humic acid substances led to enhancement of the ATZ degradation. The notable decrease of ATZ removal efficiency observed in the presence of radical scavengers and the results of free radical tests indicated thatUOH is the dominant active radical species. The mechanism investigation demonstrated that the enhancement effect could be attributed to the introduction of nZnO,which could promote the utilization of O_3, enhance the formation of superoxide radical, and further accelerate the production of hydrogen peroxide and the generation of OH/O_2^-.Xiangjuan Yuan Xuan Yan Haiming Xu Dongya Li Lei Sun Gang Cao Dongsheng Xia 2017Journal of Environmental Sciences2017,29,11:4
19Spatial distribution of IL4 controls iNKT cell-DC crosstalk in tumors显示文摘The spatiotemporal distribution of cytokines orchestrates immune responses in vivo,yet the underlying mechanisms remain to be explored.We showed here that the spatial distribution of interleukin-4(IL4)in invariant natural killer T(iNKT)cells regulated crosstalk between iNKT cells and dendritic cells(DCs)and controlled iNKT cell-mediated T-helper type 1(Th1)responses.The persistent polarization of IL4 induced by strong lipid antigens,that is,α-galactosylceramide(αGC),caused IL4 accumulation at the immunological synapse(IS),which promoted the activation of the IL4R-STAT6(signal transducer and activator of transcription 6)pathway and production of IL12 in DCs,which enhanced interferon-γ(IFNγ)production in iNKT cells.Conversely,the nonpolarized secretion of IL4 induced by Th2 lipid antigens with a short or unsaturated chain was incapable of enhancing this iNKT cell-DC crosstalk and thus shifted the immune response to a Th2-type response.The nonpolarized secretion of IL4 in response to Th2 lipid antigens was caused by the degradation of Cdc42 in iNKT cells.Moreover,reduced Cdc42 expression was observed in tumorinfiltrating iNKT cells,which impaired IL4 polarization and disturbed iNKT cell-DC crosstalk in tumors.Lu Wang Zhilan Liu Lili Wang Qielan Wu Xiang Li Di Xie Huimin Zhang Yongdeng Zhang Lusheng Gu Yanhong Xue Ting Yue Gang Liu Wei Ji Haiming Wei Tao Xu Li Bai 2020Cellular & Molecular Immunology2020,17,5:4
20Seasonal timing of stratospheric final warming associated with the intensity of stratospheric sudden warming in preceding winter显示文摘The association of seasonal timing of stratospheric final warming events(SFWs) in spring and the occurrence of major and minor stratospheric sudden warming events(SSWs) in midwinter were investigated through statistical analysis, parallel comparison, and composite analysis, based on the NCEP-NCAR reanalysis dataset covering 1958–2012. It was found that the intensity and occurrence of winter SSW events can largely affect the timing of spring SFWs. Specifically, the SFW onset dates tend to be later(earlier) after the occurrence(absence) of winter major SSWs. However, the occurrence or absence of minor SSWs does not change the frequency of early and late SFWs. A parallel comparison of the temporal evolution of the anomalous circulation and planetary-waves between major SSW and minor SSW winters indicates that the stratospheric polar vortex(polar jet) will keep being anomalously stronger 30 days after major SSW onset. And the associated significant negative Eliassen-Palm(EP) flux anomalies can persist for as long as 45 days after major SSW events. In contrast, the circulation anomalies around the occurrence of minor SSW events can last only a few days. To further verify the possible influence of the occurrence of major SSWs on the seasonal timing of SFWs, composite analysis was performed respectively for the 21 major-SSW years, 15 minor-SSW years, and the 15 non-SSW years. Generally, planetary-wave activity in the extratropical stratosphere tends to be stronger(weaker) and the westerly polar jet is anomalously weaker(stronger) in major-SSW(non-SSW) winters. But in the following spring, the planetary-wave activity is weaker(stronger) accompanied with an anomalously stronger(weaker) stratospheric polar vortex. In spring after minor-SSW years, however, the stratospheric polar vortex and the westerly polar jet exhibit a state close to climatology with relatively gentle variations.HU JingGao REN RongCai XU HaiMing YANG ShuangYan 2015Science China Earth Sciences2015,58,4:4
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