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| 1 | Homocysteine-mediated cholesterol efflux via ABCA1 and ACAT1 DNA methylation in THP-1 monocyte-derived foam cells显示文摘Homocysteine (Hcy ) 为心血管的事件作为一个流行风险因素被认出了。装载胆固醇的泡沫房间是动脉粥样硬化患者损害的一个中央部件。ATP 有约束力的盒子 transporter A1 (ABCA1 ) 它调停细胞的胆固醇和 phospholipids 的流出,是在类脂化合物的限制率的步新陈代谢。酰辅酶 A:cholesterol acyltransferase-1 (ACAT1 ) 在巨噬细胞支持胆固醇酉旨的累积,从而导致泡沫房间形成,在动脉粥样硬化的早舞台的一个特点。在这研究,有教养的导出单核白血球的泡沫房间为 24 h 与 Hcy 的临床的相关集中被孵化。胆固醇的房间和累积被发现的泡沫的两个都增加的数字,和 ABCA1 的 mRNA 和蛋白质表示层次被减少,当 ACAT1 表示面对 Hcy 被增加时。而且,而 ACAT1 DNA methylation 被使用 Hcy 的不同集中减少, ABCA1 基因的 DNA methylation 水平被增加。而且,我们的结果显示出那项 DNA methyltransferase (DNMT ) 活动和 DNA methyltransferase 1 (DNMT1 ) mRNA 表示被 Hcy 增加。DNA methylation 有功能经由 DNMT 调整 ABCA1 和 ACAT1 的表示,这被显示。在结论,这些结果建议 Hcy 导致的 ABCA1 和 ACAT1 DNA methylation 可以在导出单核白血球的泡沫房间在 ABCA1 和 ACAT1 表示和胆固醇的累积起一个潜在的作用。 | Yu Liang Xiaoling Yang Linna Ma Xin Cai Lei Wang Cheng Yang Guizhong Li Minghao Zhang Weiwei Sun Yideng Jiang | 2013 | Acta Biochimica et Biophysica Sinica2013,45,3: | 26 |
| 2 | Design and Experiment of PZT Network-based Structural Health Monitoring Scanning System显示文摘基于主动Lamb波和压电传感器网络的结构健康监测技术是一种评估航空结构健康状态的有效方法。在实际应用中,监测大型结构需要使用压电传感器网络。扫查这些压电传感器网络中的压电激励-传感通道以达到在线的结构健康监测是非常重要的。基于PXI(PCI eXtensions for Instrumentation)平台,研发了一套基于主动Lamb波和压电传感器网络的集成多通道扫查系统,该系统结构紧凑、便于携带,能大规模自动扫查激励-传感通道并进行损伤评估。提出和讨论了该系统中:4通道PXI程控增益电荷放大器的实现、支持276个激励-传感通道的外部扫查模块和集成的结构健康监测软件的实现。最后,主要讨论了系统在某型无人机碳纤维复合材料机翼盒段上的功能验证实验,包括:压电贴层的设计、激励信号频率的选择方法、损伤成像的功能性测试、系统稳定性测试和载荷对信号的影响。实验结果验证了该系统的稳定性和损伤监测功能。 | Qiu Lei Yuan Shenfang Wang Qiang Sun Yajie Yang Weiwei | 2009 | Chinese Journal of Aeronautics2009,22,5: | 23 |
| 3 | Uterine Rbpj is required for embryonic-uterine orientation and decidual remodeling via Notch pathway-independent and -dependent mechanisms显示文摘协调的子宫胚胎的轴形成并且蜕膜的改变是哺乳动物的培植以后的胚胎开发的特点。胚胎子宫的取向在起始的培植被决定并且与蜕膜的开发同步。然而,控制这些事件的分子的机制留下尽管有它的发现逃犯很长时间以前。在现在的学习,我们发现了 Rbpj 的那子宫特定的删除,槽口发信号的原子变换器,在培植以后的阶段导致了反常胚胎子宫的取向和蜕膜的 patterning,导致实质的胚胎损失。我们进一步表明在胚胎附件以前, Rbpj 授与在时间上经由身体上与子宫的雌激素受体交往的子宫的腔形状转变(ERα) 以一种槽口小径无关的方式,它为在有子宫的轴的排列的胚胎取向的起始的建立是必要的。当时在培植以后的阶段, Rbpj 直接以一种槽口小径依赖者方式调整子宫的矩阵 metalloproteinase 的表示,它为正常被要求培植以后的蜕膜的改变。这些结果证明子宫的 Rbpj 为经由指示起始的胚胎子宫的取向并且以一种阶段特定的方式保证正常蜕膜的 patterning 的正常胚胎开发是必要的。我们的数据也证实正常哺乳动物的胚胎子宫的取向要求的概念合适的指导从发展地控制了子宫的发信号。 | Shuang Zhang Shuangbo Kong Bingyan Wang Xiaohong Cheng Yongjie Chen Weiwei Wu Qiang Wang Junchao Shi Ying Zhang Shumin Wang Jinhua Lu John P Lydon Francesco DeMayo Warren S Pear Hua Han Haiyan Lin Lei Li Hongmei Wang Yan-ling Wang Bing Li Qi Chen Enkui Duan Haibin Wang | 2014 | Cell Research2014,24,8: | 12 |
| 4 | Unruptured pregnancy in a noncommunicating rudimentary horn at37 weeks with a live fetus:a case report显示文摘We report an extremely rare case of an unruptured non-communicating rudimentary horn full-term pregnancy.A woman who had a uterine malformation was misdiagnosed as uterus didelphys and gave birth to a live,healthy fetus.The correct diagnosis was not made until cesarean section at 37 4/7 weeks.The case suggests that women who are pregnant in a rudimentary horn could obtain a full-term delivery and give birth to a live and healthy baby. | Chen Cheng Weiwei Tang Lei Zhang Mei Luo Meihua Huang Xiuling Wu Guiping Wan | 2015 | The Journal of Biomedical Research2015,29,1: | 11 |
| 5 | Mortality outcomes of low-dose computed tomography screening for lung cancer in urban China:a decision analysis and implications for practice显示文摘Background: Mortality outcomes in trials of low-dose computed tomography(CT) screening for lung cancer are inconsistent. This study aimed to evaluate whether CT screening in urban areas of China could reduce lung cancer mortality and to investigate the factors that associate with the screening effect.Methods: A decision tree model with three scenarios(low-dose CT screening, chest X-ray screening, and no screening) was developed to compare screening results in a simulated Chinese urban cohort(100,000 smokers aged45-80 years). Data of participant characteristics were obtained from national registries and epidemiological surveys for estimating lung cancer prevalence. The selection of other tree variables such as sensitivities and specificities of low-dose CT and chest X-ray screening were based on literature research. Differences in lung cancer mortality(primary outcome), false diagnoses, and deaths due to false diagnosis were calculated. Sensitivity analyses were performed to identify the factors that associate with the screening results and to ascertain worst and optimal screening effects considering possible ranges of the variables.Results: Among the 100,000 subjects, there were 448,541, and 591 lung cancer deaths in the low-dose CT, chest X-ray, and no screening scenarios, respectively(17.2% reduction in low-dose CT screening over chest X-ray screening and 24.2% over no screening). The costs of the two screening scenarios were 9387 and 2497 false diagnoses and 7and 2 deaths due to false diagnosis among the 100,000 persons, respectively. The factors that most influenced death reduction with low-dose CT screening over no screening were lung cancer prevalence in the screened cohort, lowdose CT sensitivity, and proportion of early-stage cancers among low-dose CT detected lung cancers. Considering all possibilities, reduction in deaths(relative numbers) with low-dose CT screening in the worst and optimal cases were16(5.4%) and 288(40.2%) over no screening, respectively.Conclusions: In terms of mortality outcomes, our findings favor conducting low-dose CT screening in urban China.However, approaches to reducing false diagnoses and optimizing important screening conditions such as enrollment criteria for screening are highly needed. | Zixing Wang Wei Han Weiwei Zhang Fang Xue Yuyan Wang Yaoda Hu Lei Wang Chunwu Zhou Yao Huang Shijun Zhao Wei Song Xin Sui Ruihong Shi Jingmei Jiang | 2017 | Chinese Journal of Cancer2017,36,8: | 9 |
| 6 | Volumetric imaging of flame refractive index, density, and temperature using background-oriented Schlieren tomography显示文摘Volumetric imaging represents one of the major development trends of flow diagnostics due to both the advancement in hardware and the requirement for more information to further understand complicated turbulent and/or reactive flows. Backgroundoriented Schlieren tomography(BOST) has become increasingly popular due to its experimental simplicity. It has been demonstrated to be capable of simultaneously recovering the distributions of refractive index, density, and temperature of flows.However, its capability in thermometry has only been demonstrated under the axisymmetric assumption, which greatly limits its applicability. In this work, we dedicated to developing a cost-effective BOST system for the simultaneous retrieval of refractive index, density, and temperature distributions for the asymmetric flame. A few representative tomographic inversion algorithms were assessed as well. Both numerical and experimental demonstrations were conducted and the results show that our implemented BOST can successfully reconstruct the three-dimensional temperature distribution with a satisfactory accuracy. | LIU HeCong HUANG JianQing LI Lei CAI WeiWei | 2021 | Science China(Technological Sciences)2021,64,1: | 8 |
| 7 | Atomistic insight into ordered defect superstructures at novel grain boundaries in CuO nanosheets: From structures to electronic properties显示文摘Determining atomistic structures of grain boundaries (GBs) is essential to understand structure--property interplay in oxides.Here,different GB superstructures in CuO nanosheets,including (111) and (114) twinning boundaries (TBs) and (002)/(223) GB,are investigated.Unlike the lower-energy stoichiometric (111) TB,both experimental and first-principles investigations reveal a severe segregation of Cu and O vacancies and a nonstoichiometric property at (114) TB,which may facilitate ionic transportation and provide space for elemental segregation.More importantly,the calculated electronic structures have shown the increased conductivity as well as the unanticipated magnetism in both (114) TB and (002)/(223) GB.These findings could contribute to the race towards the property-directing structural design by GB engineering. | Lulu Zhao Lei Li Huaping Sheng He Zheng Shuangfeng Jia Weiwei Meng Huihui Liu Fan Cao Huayu Peng Jianbo Wang | 2019 | Nano Research2019,12,5: | 5 |
| 8 | Auranofin mitigates systemic iron overload and induces ferroptosis via distinct mechanisms显示文摘Iron homeostasis is essential for health;moreover,hepcidin-deficiency results in iron overload in both hereditary hemochromatosis and iron-loading anemia.Here,we identified iron modulators by functionally screening hepcidin agonists using a library of 640 FDA-approved drugs in human hepatic Huh7 cells.We validated the results in C57BL/6J mice and a mouse model of hemochromatosis(Hfe^(−/−)mice).Our screen revealed that the anti-rheumatoid arthritis drug auranofin(AUR)potently upregulates hepcidin expression.Interestingly,we found that canonical signaling pathways that regulate iron,including the Bmp/Smad and IL-6/Jak2/Stat3 pathways,play indispensable roles in mediating AUR’s effects.In addition,AUR induces IL-6 via the NF-κB pathway.In C57BL/6J mice,acute treatment with 5 mg/kg AUR activated hepatic IL-6/hepcidin signaling and decreased serum iron and transferrin saturation.Whereas chronically treating male Hfe^(−/−)mice with 5 mg/kg AUR activated hepatic IL-6/hepcidin signaling,decreasing systemic iron overload,but less effective in females.Further analyses revealed that estrogen reduced the ability of AUR to induce IL-6/hepcidin signaling in Huh7 cells,providing a mechanistic explanation for ineffectiveness of AUR in female Hfe^(−/−)mice.Notably,high-dose AUR(25 mg/kg)induces ferroptosis and causes lipid peroxidation through inhibition of thioredoxin reductase(TXNRD)activity.We demonstrate the ferroptosis inhibitor ferrostatin significantly protects liver toxicity induced by highdose AUR without comprising its beneficial effect on iron metabolism.In conclusion,our findings provide compelling evidence that TXNRD is a key regulator of ferroptosis,and AUR is a novel activator of hepcidin and ferroptosis via distinct mechanisms,suggesting a promising approach for treating hemochromatosis and hepcidin-deficiency related disorders. | Lei Yang Hao Wang Xiang Yang Qian Wu Peng An Xi Jin Weiwei Liu Xin Huang Yuzhu Li Shiyu Yan Shuying Shen Tingbo Liang Junxia Min Fudi Wang | 2020 | Signal Transduction and Targeted Therapy2020,5,1: | 5 |
| 9 | Technique for image fusion based on non-subsampled contourlet transform domain improved NMF显示文摘To overcome the problem of multi-sensor image fusion,a technique for image fusion based on non-subsampled contourlet transform(NSCT) domain improved nonnegative matrix factorization(NMF) is presented.Firstly,by using NSCT,multi-scale and multi-direction sparse decompositions of source images are performed.Then,an improved NMF technique is utilized to complete the fusion of low-frequency sub-images.The low-frequency fused image can be produced fast by the process which does not involve the randomization of the vectors W and H at all,in addition,the fusion course of high-frequency sub-images can be dealt with by use of the model of adaptive unit-fast-linking pulse coupled neural network(AUFLPCNN).Finally,the ultimate fused image can be obtained by synthesizing all sub-images with inverse NSCT.The simulated experiments show that the technique is effective. | KONG WeiWei LEI YingJie LEI Yang ZHANG Jie | 2010 | Science China(Information Sciences)2010,53,12: | 5 |
| 10 | A general strategy for bimetallic Pt-based nano-branched structures as highly active and stable oxygen reduction and methanol oxidation bifunctional catalysts显示文摘The morphology and size of Pt-based bimetallic alloys are known to determine their electrocatalytic performance in reactions relevant to fuel cells.Here,we report a general approach for preparing Pt-M(M=Fe,Co and Ni)bimetallic nano-branched structure(NBs)by a simple high temperature solution-phase synthesis.As-prepared Pt-M NBs show a polycrystalline structure and are rich in steps and kinks on the surface,which promote them favorable bifunctional catalytic properties in acidic electrolytes,specifically in terms of the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR).Specially,Pt-Co NBs/C catalyst shows 6.1 and 5.3 times higher in specific activity(SA)and mass activity(MA)for ORR than state-of-the-art commercial Pt/C catalysts,respectively.Moreover,it exhibits a loss of 4.0%in SA and 14.4%in MA after 10,000 cycles of accelerated durability tests(ADTs)compared with the initial activities.In addition,we also confirmed the superior MOR activity of Pt-Co NBs/C catalyst in acidic electrolytes.For Pt-M NBs with other alloying metals,the ORR and MOR activities are both higher than commercial catalysts and are in the sequence of Pt-Co/C>Pt-Fe/C>Pt-Ni/C>commercial Pt/C(or PtRu/C).The improved activities and durability can benefit from the morphological and compositional effects.This synthesis approach may be applied to develop bifunctional catalysts with enhanced ORR and MOR properties for future fuel cells designs. | Wenjuan Lei Menggang Li Lin He Xun Meng Zijie Mu Yongsheng Yu Frances MRoss Weiwei Yang | 2020 | Nano Research2020,13,3: | 5 |
| 11 | Design and synthesis by redox polymerization of a bio-based carboxylic elastomer for green tire显示文摘Poly(dibutyl itaconate-co-isoprene-co-methacrylic acid)(PDIM) elastomer was designed and synthesized by redox emulsion polymerization under mild conditions. PDIM has high molecular weight, relatively high yield, and low glass transition temperature(Tg). The structure of PDIM was determined by FTIR and NMR, and the carboxyl content was obtained by titration in a non-proton solvent. Tensile strength and elongation at break increased with increasing carboxyl content. In addition, the interaction between PDIM and silica was elucidated by rubber process analyzer(RPA) and TEM, and the results showed that the silica-PDIM interaction was strong, but the silica-silica interaction was weak. | Xinxin Zhou Runguo Wang Weiwei Lei He Qiao Haoling Ji Liqun Zhang Kuo-Chih Hua Joseph Kulig | 2015 | Science China Chemistry2015,58,10: | 4 |
| 12 | Self-transforming ultrathin α-Co(OH)2 nanosheet arrays from metal-organic framework modified graphene oxide with sandwichlike structure for efficient electrocatalytic oxygen evolution显示文摘Developing efficient and low-cost electrocatalysts for oxygen evolution reaction(OER)with high electrochemical activity and durability for diverse renewable and sustainable energy technologies remains challenging.Herein,an ultrasonic-assisted and coordination modulation strategy is developed to construct sandwich-like metal-organic framework(MOF)derived hydroxide nanosheet(NS)arrays/graphene oxide(GO)composite via one-step self-transformation route.Inducing from unsteady state,the dodecahedral ZIF-67 with Co^2+in tetrahedral coordination auto-converts into defect-rich ultrathin layered hydroxides with the interlayered ion NO3-.The self-transforming a-Co(OH)2/GO nanosheet arrays from ZIF-67(Co(OH)2-GNS)change the coordination mode of Co^2+and bring about the exposure of more metal active sites,thereby enhancing the spatial utilization ratio within the framework.As monometal-based electrocatalyst,the optimized Co(OH)2-GNS exhibits remarkable OER catalytic performance evidenced by a low overpotential of 259 mV to achieve a current density of 10 mA·cm-2 in alkaline medium,even exceeding commercial RuO2.During the oxygen evolution process,electron migration can be accelerated by the interfacial/in-plane charge polarization and local electric field,corroborated by the off-axis electron holography.Density functional theory(DFT)calculations further studied the collaboration between ultrathin Co(OH)2 NS and GO,which leads to lower energy barriers of intermediate products and greatly promotes electrocatalytic property. | Mengqiu Huang Weiwei Liu Lei Wang Jiwei Liu Guanyu Chen Wenbin You Jie Zhang Lijun Yuan Xuefeng Zhang Renchao Che | 2020 | Nano Research2020,13,3: | 4 |
| 13 | First-principles study of lithium intercalated bilayer graphene显示文摘Lithium intercalated bilayer graphene has been investigated using first-principles density functional theory calculations. Results show that there exist AB and AA stacking sequences for bilayer graphene in which the latter is more favorable for the Li storage and the former will evolve into the latter with the intercalation of Li ions. The relationship between the interlayer distance of two graphene sheets and the intercalated capacity of Li ions is discussed. It is found that structural defect is identified to store Li ions more favorably than pristine bilayer graphene and an isolated C atom vacancy in bilayer graphene can capture three Li ions between two graphene sheets. | ZHOU JingJing ZHOU WeiWei GUAN ChunMei SHEN JingQin OUYANG ChuYing LEI MinSheng SHI SiQi TANG WeiHua | 2012 | Science China(Physics,Mechanics & Astronomy)2012,55,8: | 4 |
| 14 | Vertical Structure of the Tidal Currents on the Continental Shelf of the East China Sea显示文摘The available data on tidal currents spanning periods greater than six months for the continental shelf of the East China Sea (26°30.052′N, 122°35.998′E) were analyzed using several methods. Tidal Current Harmonic Analysis results demonstrated that semi-diurnal tides dominated the current movement. The tidal currents of the principal diurnal and semidiurnal rotated clockwise with depth, with the deflection of the major semi-axes to the right in the upper layer and to the left in the lower layer. The vertical structures of two principal semi-diurnal constituents-M2 and S2-were similar, which indicates that the tidal currents are mainly barotropic in this area. The main features of the variation of the four principal tidal constituents with depth demonstrate that the currents in this region are influenced by the upper and lower boundary layers. Therefore, the tidal constituents of the shallow water are similar. Different vertical modes were calculated based on the Empirical Orthogonal Function (EOF) analysis of the Eastern and Northern components of the tidal currents, with a variance contribution for the zero-order model of at least 90%. The variance contribution of the baroclinic model is minimal, which further reveals a strong barotropic character for the tidal currents of this region. | LI Lei JIANG Weiwei LI Peiliang YANG Bo | 2012 | Journal of Ocean University of China2012,11,3: | 4 |
| 15 | Magnetic-field enhanced high-thermoelectric performance in topological Dirac semimetal Cd3As2 crystal显示文摘Thermoelectric materials can be used to convert heat to electric power through the Seebeck effect. We study magneto-thermoelectric figure of merit(ZT) in three-dimensional Dirac semimetal Cd_3As_2 crystal.It is found that enhancement of power factor and reduction of thermal conductivity can be realized at the same time through magnetic field although magnetoresistivity is greatly increased. ZT can be highly enhanced from 0.17 to 1.1 by more than six times around 350 K under a perpendicular magnetic field of 7 T. The huge enhancement of ZT by magnetic field arises from the linear Dirac band with large Fermi velocity and the large electric thermal conductivity in Cd_3As_2. Our work paves a new way to greatly enhance the thermoelectric performance in the quantum topological materials. | Honghui Wang Xigang Luo Weiwei Chen Naizhou Wang Bin Lei Fanbao Meng Chao Shang Likuan Ma Tao Wu Xi Dai Zhengfei Wang Xianhui Chen | 2018 | Science Bulletin2018,63,7: | 4 |
| 16 | Direct Observation of the Strong Interaction Between Carbon Nanotubes and Quartz Substrate显示文摘We present a chemical vapor deposition(CVD)method for the growth of uniform single-walled carbon nanotube(SWNT)arrays on a stable temperature(ST)-cut single crystal quartz substrate using a mixture of methanol and ethanol as carbon source.It is found that introducing methanol during the growth can improve the density and the length of the well-aligned SWNTs in the arrays as well as increase the SWNT/quartz interaction.Obvious“up-shifts”of G-band frequencies in the Raman spectra have been found for the aligned SWNTs.A well-designed control experiment shows that the G-band“up-shifts”originate from the strong interaction between SWNTs and the quartz substrate.It is believed that exploring this interaction will help to elucidate the growth mechanism;ultimately,this will help realize the promise of controlling the chirality of SWNTs. | Lei Ding Weiwei Zhou Thomas P.McNicholas Jinyong Wang Haibin Chu Yan Li Jie Liu | 2009 | Nano Research2009,2,11: | 4 |
| 17 | Abutment pressure distribution for longwall face mining through abandoned roadways显示文摘Abutment pressure distribution is different when a longwall panel is passing through the abandoned gate roads in a damaged coal seam. According to the geological condition of panel E13103 in Cuijiazhai Coal Mine in China, theoretical analysis and finite element numerical simulation were used to determine the front pressure distribution characteristics when the longwall face is 70, 50, 30, 20, 10, and 5 m from the abandoned roadways. The research results show that the influence range of abutment pressure is 40 to 45 m outby the face, and the peak value of front abutment pressure is related to the distance between the face and abandoned roadways. When the distance between the longwall face and abandoned roadways is reduced from 50 to 10 m, the front abutment pressure peak value kept increasing. When the distance is 10 m, it has reached the maximum. The peak value is located in 5 to 6 m outby the faceline. When the distance between the longwall face and abandoned roadways is reduced from 10 to 5 m, the front abutment pressure sharply decreases, the intact coal yields and is even in plastic state. The peak value transfers to the other side of the abandoned roadways. The research results provide a theoretical basis for determining the advance support distance of two roadways in the panel and the reinforcement for face stability when the longwall face is passing through the abandoned roadways. | Yang Li Mingxing Lei Haosen Wang Cheng Li Weiwei Li Yang Tao Jingyi Wang | 2019 | International Journal of Mining Science and Technology2019,29,1: | 4 |
| 18 | Long noncoding RNA AANCR modulates innate antiviral responses by blocking miR-210-dependent MITA downregulation in teleost fish,Miichthys miiuy显示文摘Viral infection induces the initiation of antiviral effectors and cytokines which are critical mediators of innate antiviral responses.The critical molecular determinants are responsible for triggering an appropriate immune response.Long noncoding RNAs(lncRNAs)have emerged as new gene modulators involved in various biological processes,while how lncRNAs operate in lower vertebrates are still unknown.Here,we discover a long noncoding RNA,termed antiviral-associated long noncoding RNA(AANCR),as a novel regulator for innate antiviral responses in teleost fish.The results indicate that fish MITA plays an essential role in host antiviral responses and inhibition of Siniperca chuatsi rhabdovirus(SCRV)production.miR-210 reduces MITA expression and suppress MITA-mediated antiviral responses,which may help viruses evade host antiviral responses.Further,AANCR functions as a competing endogenous RNA(ceRNA)for miR-210 to control protein abundance of MITA,thereby inhibiting SCRV replication and promoting antiviral responses.Our data not only shed new light on understanding the function role of lncRNA in biological processes in teleost fish,but confirmed the hypothesis that ceRNA networks exist widely in vertebrates. | Qing Chu Tianjun Xu Weiwei Zheng Renjie Chang Lei Zhang | 2021 | Science China(Life Sciences)2021,64,7: | 3 |
| 19 | Responses of nighttime sap flow to atmospheric and soil dryness and its potential roles for shrubs on the Loess Plateau of China显示文摘Aims Nocturnal sap flow(E_(night))has been observed in a variety of plant species and environmental conditions.In water-limited environ-ments,E_(night) is important in the regulation of plant water’s physi-ology.This study was designed to evaluate the way in which E_(night)(defined as sap flow from 20:30 to 06:00)responded to changes in the atmospheric vapor pressure deficit(VPD)and the soil water con-tent(SWC),and explored its potential physiological significance for different plant species in a semi-arid area.Methods We selected three shrub species:Vitex negundo L.(VN),Hippophae rhamnoides L.(HR)and Spiraea pubescens Turcz(SP)in the semi-arid Loess Plateau of China.The plots of the three communities dominated by each of three species were on the same hill slope.Half-hourly sap flow density was measured in six to seven sample stems for each species during the main grow-ing season(June to August 2015).VPD,SWC,leaf water potential(Ψleaf)and stomatal conductance(G_(s))were measured at the same time.Regression analyses were conducted to determine the rela-tionships between E_(night),E_(day),E_(night)/E_(daily),VPD and SWC at half-hourly and daily time scales,as well as between E_(night),E_(day) andΨleaf.Important Findings The mean values of E_(night) and E_(day) were higher,but E_(night)/E_(daily) val-ues were lower for VN compared to HR and SP.The responses of sap flow density to VPD and SWC varied at different temporal scales.VPD was the dominant factor that affected E_(night) and E_(day) at the half-hourly scale for all three species.In contrast,SWC was the key factor that influenced E_(day) at the daily time scale.The values of E_(day) and E_(night)/E_(daily) correlated negatively with SWC because the effect of SWC was stronger on E_(day) than on E_(night).Although the low fraction of E_(night)/E_(daily)(4%-7%)may indicate a minor short-term effect of E_(night) on the standing water balance,E_(night) had eco-physiologically significance to the plants.The discrepancy inΨleaf between sunset and the following day’s predawn(ΔΨ)indicated that stem refilling occurred during this period.SP had the higher fraction of recharge water among the three species,as it had the relatively higher value ofΔΨ/E_(night).E_(night) had positive relation-ship with predawn Gs.The increased Gs facilitated rapid onset of photosynthesis in the early morning.In addition,the positive correlation between E_(night) and E_(day) from 06:00 to 10:30 suggested that E_(night) was beneficial for transpiration in the following morning.The responses of E_(night) to VPD and SWC indicated differences in plant adaptation to drought stress,which provides important infor-mation for our understanding of the reactions to climate changes among species in semi-arid areas. | Weiwei Fang Nan Lu Yu Zhang Lei Jiao Bojie Fu | 2018 | Journal of Plant Ecology2018,11,5: | 3 |
| 20 | 中国城市人群低剂量计算机断层扫描筛查肺癌的死亡率结果:决策分析和实践意义显示文摘背景与目的不同低剂量计算机断层扫描(computed tomography,CT)筛查肺癌试验得出的死亡率结果不一致。本研究旨在评价中国城市CT筛查是否能够降低肺癌死亡率,并探讨影响筛查效果的因素。方法建立了3种场景(低剂量CT筛查、胸部X线筛查和无筛查)的决策树模型来比较模拟的中国城市人群(100,000例年龄45–80岁的吸烟者)的筛查结果。从国家登记和流行病学调查中获得了参与者特征数据并估算了肺癌患病比例。根据文献调研选择了低剂量CT和胸部X线筛查的灵敏度和特异度等其他树变量。计算了3种筛查方法间肺癌死亡率(主要结局)、误诊和误诊导致死亡的差异。通过敏感性分析找出了与筛查结果相关的因素,并确定了在变量可能范围内的最差和最优筛查效果。结果 100,000例研究对象中,低剂量CT、胸部X线和无筛查场景分别有448例、541例和591例肺癌死亡(低剂量CT筛查比胸部X线筛查死亡人数减少17.2%,比无筛查减少24.2%)。100,000例研究对象中,2种筛查场景的代价分别为9387例和2497例误诊及7例和2例误诊导致的死亡。低剂量CT筛查比无筛查的死亡数降低,影响最大的因素是筛查人群的肺癌患病比例、低剂量CT的灵敏度和低剂量CT检出肺癌中早期癌的比例。综合了所有可能性,低剂量CT筛查肺癌的死亡人数(相对数)在最坏和最好情况下分别比无筛查降低了16例(5.4%)和288例(40.2%)。结论就死亡率结局而言,我们的研究结果支持在中国城市人群中进行低剂量CT筛查。然而,急需策略来减少误诊和优化纳入标准等重要筛查条件。 | Zixing Wang Wei Han Weiwei Zhang Fang Xue Yuyan Wang Yaoda Hu Lei Wang Chunwu Zhou Yao Huang Shijun Zhao Wei Song Xin Sui Ruihong Shi Jingmei Jiang | 2018 | 癌症2018,37,8: | 3 |