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Luminescence study of europium(III) tris(β-diketonato)/phosphonate complexes in chloroform

Journal of Rare Earths 2008年第2期26卷 185-191页

作者： Stefan lis Zbigniew Piskula Krzysztof Staninski Sayaka Tamaki Masayuki Inoue Yuko Hasegawa Department of Rare Earths Faculty of Chemistry Adam Mickiewicz University Grunwaldzka 6 Department of Chemistry Faculty of Science Science University of Tokyo

The extraction of Eu（Ⅲ） with β-diketone, HA, and monodentate or bidentate Lewis bases, B, into chloroform and the luminescence properties of the extracted species were studied. Pivaloyltrifluoroacetone, Hpta, and 2-thenoyltfifluoroacetone, Htta, were used as the β-diketones. The Lewis bases, B, were tetraethyl methylene diphosphonate, POPO, which was bidentate, and diethyl benzylphosphonate, PhPO which was monodentate. Based on the extraction data, the stability constants, log β, of the first complexes between tfis（β-diketonato）Eu（Ⅲ） and the phosphonate, EuA3B, were determined to be 6.0 for the POPO complex and 3.40 for the PhPO complex. The Eu（Ⅲ） luminescence intensity in the EuA3POPO was larger than EuA3 where A was either pta or tta at similar concentrations of Eu（Ⅲ）, while that in Eu（pta）3PhPO was stronger than EuA3; however, in Eu（tta）3PhPO, it was weaker than Eu（tta）3. The POPO functions as a sensitizer, and the PhPO functions as a quencher for the tta chelate and as a sensitizer for the pta chelate. From the lifetime and quantum yield, φ, of the Eu（Ⅲ） luminescence in the complexes as well as the observation of the extractability of Eu（Ⅲ） with the Hpta and the phosphonates and of the luminescence spectra of the complexes, it was confirmed that the extraction of Eu（Ⅲ） was remarkably enhanced with a β-diketonate and a strong Lewis base, and also the ternary complex that was formed as the extracted species, showed luminescence enhancement. This phenomenon may be due the formation of a strong bond between the Eu（Ⅲ） and the strong Lewis base leading to more hydrophobicity in the extracted species and also to more effective energy transfer from the Lewis base to the Eu（Ⅲ）. It was not significant whether the donor atoms were N or O.

关键词： tris(β-diketonato)Eu(Ⅲ) extraction luminescence phosphonate ligands rare earths

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Impact of Background Dynamic and Thermodynamic States on Distinctive Annual Cycle of Near-Equatorial Tropical Cyclogenesis over the Western North Pacific

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Journal of Meteorological Research 2020年第4期34卷 822-835页

作者： Liyuan DENG tim LI Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044China International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of HawaiiHonoluluHI 96822USA

In a sharp contrast to tropical cyclone(TC) genesis over the main development region of the western North Pacific(WNP), near-equatorial(0°-5°N) TCs exhibit a distinctive annual cycle, peaking in boreal winter and being inactive in boreal summer. The relative roles of dynamic and thermodynamic background states on near-equatorial TCs formation were investigated based on the observational diagnosis of the genesis potential index(GPI) and high-resolution model simulations. It is found that the background vorticity makes a major contribution to the distinctive annual cycle, while mean temperature and specific humidity fields are not critical. Numerical simulations further indicate that seasonal mean cyclonic vorticity in boreal winter has three effects on TC genesis near the equator. First, the environmental cyclonic vorticity interacts with TC vortex to promote a mid-level outflow, which strengthens boundary layer friction induced ascending motion and thus condensational heating. Second, it produces an equivalent Coriolis effect(via enhanced absolute vorticity), which strengthens positive feedback between primary and secondary circulation. Third, it helps to merge small-scale vortical hot towers(VHTs) into a mesoscale core through vorticity segregation process. However, background vorticity in boreal summer has an opposite effect on TC development near the equator.

关键词： near-equatorial tropical cyclone(TC) equivalent Coriolis effect vorticity segregation

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An Empirical Model of Tropical Cyclone Intensity Forecast in the Western North Pacific

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Journal of Meteorological Research 2022年第5期36卷 691-702页

作者： Chen MA tim LI Jiangsu Meteorological Observatory Jiangsu Meteorological BureauNanjing 210019China Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)NanjingUniversityof Information Science&TechnologyNanjing210044China International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversityofHawaiiHI96822USA Key Laboratory of Transportation Meteorology China Meteorological AdministrationNanjing 210019China

The relative impact of environmental parameters on tropical cyclone(TC) intensification rate(IR) was investigated through a box difference index(BDI) method, using TC best track data from Joint Typhoon warning Center and environmental fields from the NCEP final analysis data over the western North Pacific(WNP) during 2000–*** are total 6307 TC samples with a 6-h interval, of which about 14% belong to rapid intensification(RI) category. The analysis shows that RI occurs more frequently with higher environmental sea surface temperature, higher oceanic heat content, and lower upper-tropospheric temperature. A moderate easterly shear is more favorable for TC intensification. TC intensification happens mostly equatorward of 20°N while TC weakening happens mostly when TCs are located in the northwest of the basin. Mid-tropospheric relative humidity and vertical velocity are good indicators separating the intensification and non-intensification groups. A statistical model for TC intensity prediction was constructed based on six environmental predictors, with or without initial TC intensity. Both models are skillful based on Brier skill score(BSS) relative to climatology and in comparison with other statistical models, for both a training period(2000–2018) and an independent forecast period(2019–2020).

关键词： tropical cyclone rapid intensification prediction model

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Increasing Trend of Summertime Synoptic wave Train Activity over the Western North Pacific since 1950

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Journal of Meteorological Research 2020年第5期34卷 1013-1024页

作者： Xinyi ZHOU tim LI Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of HawaiiHonoluluHI 96822USA

The change of summertime synoptic-scale wave train(SWT) activity over the western North Pacific(WNP) since1950 was investigated based on the NCEP–NCAR reanalysis data. It is found that the intensity of SWT has a rising trend, while its structure and phase propagation characteristics remain unchanged. Environmental factors responsible for the rising trend are investigated. By separating the whole period into three warming phases(P1: 1950–1958, P2:1978–1986, and P3: 2006–2014), we found that even though the vertical velocity shows a rising trend, the background low-level vorticity over the monsoon trough region increases from P1 to P2 but decreases from P2 to P3, and so is the low-level barotropic energy conversion(CK). Thus, just the environmental dynamic factor could not explain the continuous rising SWT trend. On the other hand, thermodynamic factor, such as the sea surface temperature(SST), moisture, and atmospheric instability, shows a clear step-by-step increasing trend. A non-dimensional synoptic activity index(SAI) that combines the dynamic and thermodynamic factors is then proposed. This index well captures the observed long-term trend of the SWT intensity.

关键词： global warming synoptic wave train barotropic energy conversion(CK) atmospheric instability parameter synoptic activity index(SAI)

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An Improved Method for Defining Short-Term Climate Anomalies

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Journal of Meteorological Research 2021年第6期35卷 1012-1022页

作者： Xuan CHEN tim LI Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii atManoaHonoluluHI 96822USA

A conventional method to define short-term climate anomalies for atmospheric and oceanic variables,recommended by the World Meteorological Organization(WMO),is the departure from a 30-yr climatological mean in the preceding three *** a method,however,introduces spurious errors such as sudden jumps and artificial trends.A new method,named a trend correctional method,is introduced to eliminate the *** demonstrate the capability of this new method,we examine a set of idealized cases first by superposing a"true"interannual or interdecadal signal onto a linear or a nonlinear *** to the conventional method,the trend correctional method is able to retain,to a large extent,the"true"anomaly ***,we examined real-time *** anomaly time series derived based on the trend correctional method show a better agreement with the observed anomaly *** rootmean-square error is greatly improved,comparing to that calculated based on the conventional ***,the results from both the idealized and real cases demonstrate that the new method has a clear advantage to the conventional method in deriving true climate anomalies,in particular under the ongoing global warming circumstance.

关键词： long-term trend climate anomaly definition trend correctional method

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Sensitivity of the Size of a TC to Sea Surface Temperatures in Its Outer Region

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Journal of Meteorological Research 2023年第6期37卷 829-840页

作者： Mingyu BI tim LI Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing210044China Key Laboratory for Typhoon Monitoring&Forecasting of Zhejiang Province Wenzhou325000China International Pacific Research Center and Department of Atmospheric Sciences University of Hawaii at ManoaHonoluluHawaii96822USA

We investigated the sensitivity of the size of a tropical cyclone(TC) to warming or cooling sea surface temperatures(SST) in its outer region by simulating the SST beyond a radius of 200 km from the TC *** experiments showed that an increased SST outside the core region of the TC had a negative effect on its *** in the outer region contributed to the local enhancement of the latent heat flux from sea surface,which promoted the development of small-scale convection and warmed the lower and *** warming altered the local pressure gradient force in the upper and lower troposphere in such a way that it weakened the secondary circulation of the TC and led to suppression of the spiral rainbands outside the *** analysis showed that the outward-propagating rainband structure favored an increase in the size of the *** diabatic heat released by the rainbands induced an inflow at lower levels,facilitating expansion of the *** greater the distance of the rainbands from the center of the TC,given the same amplitude of diabatic heating,the stronger the forced inflow,resulting in a faster increase in the size of the TC.

关键词： tropical cyclones(TCs) size rainbands sea surface temperature(SST)

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Physical Processes Responsible for the Interannual Variability of Sea Ice Concentration in Arctic in Boreal Autumn since 1979

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Journal of Meteorological Research 2017年第3期31卷 468-475页

作者： Lei ZHANG tim LI Climate Dynamics Research Center and Earth System Modeling Center International Laboratory on Climate and Environment ChangeNanjing University of Information Science & Technology Department of Atmospheric Sciences University of Hawaii

Arctic sea ice concentration （ASIC） in boreal autumn exhibits prominent interannual variability since 1979. The physical mechanism responsible for the year-to-year variation of ASIC is investigated through observational data analyses and idealized numerical modeling. It is found that the ASIC interannual variability is closely associated with the anomalous meridional circulations over the Northern Hemisphere, which is further linked with the tropical sea surface temperature （SST） forcing. A tropics-wide SST cooling anomaly leads to an enhanced meridional SST gradi- ent to the north of the equator in boreal summer, generating strengthened and northward shifting Hadley circulation over the Northern Hemisphere. Consequently, the meridional circulations are enhanced and pushed poleward, lead- ing to an enhanced descending motion at the North Pole, surrounded by an ascending motion anomaly; the surface outflow turns into easterly anomalies, opposing the mean-state winds. As a result, positive cloudiness and weakened surface wind speed emerge, which reduce ASIC through changes in the surface latent heat flux and the downward longwave radiation.

关键词： Arctic sea ice variability interannual variability tropical forcing meridional circulations

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转录组和代谢组分析盐度对盐单胞菌合成羟基四氢嘧啶的影响

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水生生物学报 2024年第7期48卷 1193-1204页

作者：张蔓邢江娃朱德锐李永臻青海大学医学部基础医学研究中心西宁810016

为了明确不同盐度对Halomonas campaniensis XH26合成羟基四氢嘧啶(5-hydroxyectoine,5-HE)代谢通路和基础代谢的影响,研究采用无NaCl作为对照组,以12%、14%和16%NaCl浓度梯度作为高盐组。利用转录组测序和液质联用技术(LC-MS)分析了***... 详细信息

为了明确不同盐度对Halomonas campaniensis XH26合成羟基四氢嘧啶(5-hydroxyectoine,5-HE)代谢通路和基础代谢的影响,研究采用无NaCl作为对照组,以12%、14%和16%NaCl浓度梯度作为高盐组。利用转录组测序和液质联用技术(LC-MS)分析了*** XH26在不同NaCl浓度条件下的差异表达基因和差异代谢物,并利用qPCR对与Ectoine和5-HE合成密切相关的差异基因的表达量进行了相对定量分析验证。结果显示,5-HE合成量在高盐组间随盐梯度先增加后降低,并在14%NaCl浓度时达到最高。转录组结果显示,在186个KEGG代谢通路中,差异表达基因在ABC转运蛋白、双组分系统、鞭毛组装等通路中高度富集。筛选到与5-HE合成代谢相关的7个关键基因表达存在差异,包括lysC、ectA、ectB、ectC、ectD、doeC和doeD。qPCR验证结果与转录组学分析结果基本一致。代谢组分析共发现了1159个差异代谢物,主要富集在氨基酸代谢、辅因子-维生素代谢和碳水化合物等代谢通路。研究还筛选出了显著差异的相容性溶质,包括四氢嘧啶、羟基四氢嘧啶和甜菜碱。研究分析了菌株*** XH26的耐盐特性及盐适应机制,初步明确了5-HE产量及合成基因簇表达随盐度变化的规律,为高产5-HE的野生菌的优化和基因工程菌的构建提供了理论基础。

关键词：转录组学代谢组学盐单胞菌羟基四氢嘧啶

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Utility of direct 3D co-culture model for chondrogenic differentiation of mesenchymal stem cells on hyaluronan scaffold(Hyaff-11)

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Regenerative Biomaterials 2020年第6期7卷 543-552页

作者： Iwona Deszcz Anna lis-Nawara Piotr Grelewski Szymon Dragan Julia Bar Department of Immunopathology and Molecular Biology Wroclaw Medical UniversityBujwida 4450-345 WroclawPoland Department and Clinic of Orthopedic and Traumatologic Surgery Wroclaw Medical UniversityBujwida 4450-345 WroclawPoland

This study presents direct 2D and 3D co-culture model of mesenchymal stem cells(MSCs)line with chondrocytes isolated from patients with osteoarthritis(unaffected area).MSCs differentiation into chondrocytes after 14,17 days was checked by estimation of collagen Ⅰ,Ⅱ,Ⅹ,aggrecan expression using ***,localization of cells on Hyaff-11 was performed using enzymatic technique and THUNDER Imaging *** showed,that MSCs/chondrocytes 3D co-culture induced suitable conditions for chondrocytes grow and MSCs differentiation than 2D *** that differentiated cells on Hyaff-11 expressed collagen Ⅹ,they showed high collagen Ⅱ(80%)and aggrecan(60%)expression with simultaneous decrease of collagen Ⅰ expression(10%).The high concentration of differentiated cells on Hyaff-11,indicate that this structure has an impact on cells cooperation and *** conclusion,we suggest that high expression of collagen Ⅱ and aggrecan in 3D co-culture model,indicate that cooperation between different subpopulations may have synergistic impact on MSCs chondrogenic *** the high concentration and localization of cells growing in deeper layers of membrane in 3D co-culture,indicate that induced microenvironmental enhance cell migration within ***,we suggest that co-culture model might be useful for construction a bioactive structure for cartilage tissue regeneration.

关键词： articular cartilage regeneration chondrogenesis direct co-culture Hyaff-11

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Prenatal multiple micronutrient-fortified balanced energy-protein supplementation and newborn telomere length and mitochondrial DNA content: a randomized controlled efficacy trial in rural Burkina Faso

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Food Science and Human Wellness 2024年

作者： Giles T.Hanley-Cook Yuri Bastos-Moreira Dries S.Martens Trenton Dailey-Chwalibóg Laeticia Celine Toe Brenda de Kok Lionel Ouédraogo Alemayehu Argaw Kokeb Tesfamariam Patrick Kolsteren Lieven Huybregts tim S.Nawrot Sarah De Saeger Marthe De Boevre Carl Lachat Department of Food Technology， Safety and Health， Faculty of Bioscience Engineering， Ghent University Center of Excellence in Mycotoxicology and Public Health， MYTOXSOUTH~(?) Coordination Unit， Faculty of Pharmaceutical Sciences， Ghent University Centre for Environmental Sciences， Hasselt University Unité Nutrition et Maladies Métaboliques， Institut de Recherche en Sciences de la Santé (IRSS) Centre Muraz Center of Excellence in Mycotoxicology and Public Health， MYTOXSOUTH? Coordination Unit， Faculty of Pharmaceutical Sciences， Ghent University Nutrition， Diets， and Health Unit， Department of Food and Nutrition Policy， International Food Policy Research Institute (IFPRI) Department of Public Health & Primary Care， University of Leuven Department of Biotechnology and Food Technology， Faculty of Science， University of Johannesburg， Doornfontein Campus

Background: Evidence regarding the effectiveness of prenatal nutritional supplements has mainly considered anthropometric pregnancy outcomes. The effect on markers of health and disease， such as offspring telomere length (TL) and mitochondrial DNA content (mtDNAc) is unknown. Objectives: We assessed the efficacy of maternal multiple micronutrient (MMN)-fortified balanced-energy protein (BEP) and iron-folic acid (IFA) supplementation on newborn TL as a secondary outcome and mtDNAc as a non-declared outcome. Design: We conducted a randomized controlled trial in rural Burkina Faso， among pregnant females (15-40 years old) enrolled at 0.05) by adjusting the regression models for potential prognostic factors of study outcomes at enrollment. Exploratory analyses indicated higher， but non-significantly different mtDNAc among children born either small-for-gestational age， low birthweight， or preterm. Conclusions: Newborns from mothers who received daily nutritional supplements across gestation did not have different relative TL or mtDNAc.

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