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Isolation and characterization of three pairs of verrucosidin epimers from the marine sediment‑derived fungus Penicillium cyclopium and confguration revision of penicyrone A and related analogues

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Marine Life Science & Technology 2023年第2期5卷 223-231页

作者： Yan-He Li Attila Mándi Hong-Lei Li Xiao-Ming Li Xin Li Ling-Hong Meng Sui-Qun Yang Xiao-Shan Shi tibor Kurtán Bin-Gui Wang CAS and Shandong Province Key Laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of Sciencesand Laboratory of Marine Biology and Biotechnology at the Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China School of Marine Science University of Chinese Academy of SciencesBeijing 100049China Department of Organic Chemistry University of DebrecenEgyetem Tér 1Debrecen 4032Hungary Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Verrucosidins,a methylatedα-pyrone class of polyketides rarely reported upon,have been implicated in one or more neurological *** the signifcance of verrucosidins as neurotoxins,the absolute confgurations of most of the derivatives have not been accurately characterized *** this study,three pairs of C-9 epimeric verrucosidin derivatives,including the known compounds penicyrones A and B(1a/1b)and 9-O-methylpenicyrones A and B(2a/2b),the new compounds 9-O-ethylpenicyrones A and B(3a/3b),together with the related known derivative verrucosidin(4),were isolated and identifed from the culture extract of Penicillium cyclopium SD-413,which was obtained from the marine sediment collected from the East China *** structures were established based on an in-depth analysis of nuclear magnetic resonances(NMR)and mass spectroscopic *** of the absolute confgurations of these compounds was accomplished by Mosher’s method and time-dependent density functional theory(TDDFT)calculations of electronic circular dichroism(ECD)and optical rotation(OR).The confgurational assignment of penicyrone A demonstrated that the previously reported C-6 absolute confguration of verrucosidin derivatives needs to be revised from(6S)to(6R).The 9R/9S epimers of compounds 1–3 were found to exhibit growth inhibition against some pathogenic bacteria,indicating that they have potential as lead compounds for the creation of antimicrobial agents.

关键词： Marine-derived fungus Penicillium cyclopium Verrucosidin derivatives TDDFT-ECD calculations Mosher’s method Antimicrobial activity

使用扫描隧道显微镜(STM)研究石墨及碳纤维的表面结构特征

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现代地质 1990年第1期4卷 58-63,T004页

作者：马喆生 tibor Zoltai 中国地质大学美国明尼苏达大学

本文所介绍的扫描隧道显微镜是一种用于表面研究的新技术,它可以实时地观察到物质表面原子在真实空间的排列及其电子性质。作者采用这种技术观察了天然石墨的(001)表面结构并首次拍摄了垂直于(001)方向的石墨的STM图象。在对碳纤维的观... 详细信息

本文所介绍的扫描隧道显微镜是一种用于表面研究的新技术,它可以实时地观察到物质表面原子在真实空间的排列及其电子性质。作者采用这种技术观察了天然石墨的(001)表面结构并首次拍摄了垂直于(001)方向的石墨的STM图象。在对碳纤维的观察中发现了一种类似于金刚石型的表面结构。

关键词：表面结构扫描隧道显微镜隧道效应石墨碳纤维变形四面体

Are Mikvehs Responsible for GBS Carriers among Orthodox Jewish Women?—A Prospective Observational Study

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Open Journal of Obstetrics and Gynecology 2020年第7期10卷 909-913页

作者： Jacky Herzlich Daniel Lubin Yehudit Schindler Osnat wittmann Ronella Marom Departments of Neonatology Mahayanei Hayeshua Center Bney Brak Israel Departments of Neonatology Lis Maternity Hospital Tel Aviv Sourasky Medical Center Tel Aviv Israel Sackler Faculty of Medicine Tel Aviv University Tel Aviv Israel Departments of Microbiology Mahayanei Hayeshua Center Bney Brak Israel

Background: Maternal colonization with group B streptococcus (GBS) is an important risk factor for neonatal sepsis. A “mikveh” is a pool of water for ritual immersion by Jewish women. It had been reported to be a risk factor for GBS colonization. Objective: To determine whether there is an association between ritual immersion in the mikveh pools and GBS carriership. Methods: Water samples and bacterial swabs were taken from eight mikveh pools centers at two separate occasions and tested for GBS growth. For determination of the total number of live, aerobic bacteria, each sample was grown on strep selective agar for 48 hours at 37°C and CO2 5%. Results: All the samples were tested. No trace of GBS was found in any of the samples. Conclusions: The findings of this study refute earlier findings and suggest that there is no association between ritual immersion in mikvehs and GBS carriership.

关键词： Group B Streptococcus Carrier Mikveh Colonization Religiosity Early on Set Sepsis

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复碱化混凝土孔溶液的pH值(英文)

建筑材料学报 2003年第2期6卷 111-117页

作者： A. Gerdes F. H. wittmann Research Center Karlsruhe KarlsruheAedificat Institute Freiburg Germany Germany

碳化混凝土的复碱化是用碳酸钙缓冲溶液浸渍混凝土的电化学过程,目的是使混凝土孔溶液的pH值稳定在10以上,从而防止混凝土的进一步碳化.然而,该方法的实际应用表明:虽然孔溶液中已明显含有足量的碱(Na+,K+,Li+),但pH值仍降到10以下.本... 详细信息

碳化混凝土的复碱化是用碳酸钙缓冲溶液浸渍混凝土的电化学过程,目的是使混凝土孔溶液的pH值稳定在10以上,从而防止混凝土的进一步碳化.然而,该方法的实际应用表明:虽然孔溶液中已明显含有足量的碱(Na+,K+,Li+),但pH值仍降到10以下.本文通过试验提出了一个用以解释pH值随时间降低的假说,结果表明:由于混凝土孔溶液中存在溶解的硫酸盐,因此单纯提高孔溶液的碱离子(碳酸盐)相对含量,不能确保其pH值高于10.用提出的化学机理可解释混凝土电化学复碱化技术实际应用中观察到的现象,但是,由于混凝土孔溶液中溶解离子相互作用十分复杂,目前还不能在复碱化技术中对其加以考虑,因此复碱化技术尚不能被进一步推荐应用.

关键词：碳化混凝土复碱化硫酸盐孔溶液 pH值

基于氯离子分布的氯离子渗透参数计算的新方法

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港工技术 2006年第3期43卷 19-22页

作者：范宏赵铁军 F H wittmann 西安建筑科技大学西安710055 青岛理工大学青岛266033

根据混凝土中氯离子的分布对氯离子侵入性能进行评价时,混凝土粉末样品的采集,氯离子含量的测试和表达方式,均可对评价结果产生影响。在干湿循环条件下,以理论上的表面氯离子浓度为主要评价参数对氯离子的渗透性能进行评价的方法不尽合... 详细信息

根据混凝土中氯离子的分布对氯离子侵入性能进行评价时,混凝土粉末样品的采集,氯离子含量的测试和表达方式,均可对评价结果产生影响。在干湿循环条件下,以理论上的表面氯离子浓度为主要评价参数对氯离子的渗透性能进行评价的方法不尽合理。通过对暴露26年后的青岛北海船厂码头中大量的混凝土芯样中氯离子分布的分析和计算,结合其它文献中氯离子分布的数据,提出了以扩散区与对流区界面为扩散表面,以界面处的氯离子浓度为扩散表面浓度,评价氯离子侵入性能和进行寿命预测的方法。

关键词：氯离子分布拟合扩散系数

Minimization vs tailoring:Where do we stand with personalized immunosuppression during renal transplantation in 2015?

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World Journal of Transplantation 2015年第3期5卷 73-80页

作者： Lajos Zsom László Wagner tibor Fül?p Division of Transplantation Institute of SurgeryUniversity of Debrecen Department of Transplantation and Surgery Semmelweis University Division of Nephrology Department of MedicineUniversity of Mississippi Medical Center

The introduction of novel immunosuppressive agents over the last two decades and the improvement of our diagnostic tools for early detection of antibodymediated injury offer us an opportunity, if not a mandate, to better match the immunosuppression needs of the individual patients with side effects of the therapy. However, immunosuppressive regimens in the majority of programs remain mostly protocol-driven, with relatively little inter-program heterogeneity in certain areas of the world. Emerging data showing different outcomes with a particular immunosuppressive strategy in populations with varying immunological risks underscore a real potential for "personalized medicine" in renal transplantation. Studies demonstrating marked differences in the adverse-effect profiles of individual drugs including the risk for viral infections, malignancy and renal toxicity call for a paradigm shift away from a "one size fits all" approach to an individually tailored immunosuppressive therapy for renal transplant recipients, assisted by both screening for predictors of graft loss and paying close attention to dose or class-related adverse effects. Our paper explores some of the opportunities during the care of these patients. Potential areas of improvements may include:(1) a thorough assessment of immunological and metabolic risk profile of each renal transplant recipient;(2) screening for predictors of graft loss and early signs of antibody-mediated rejection with donor-specific antibodies, protocol biopsies and proteinuria(including close follow up of adverse effects with dose adjustments or conversions as necessary); and(3) increased awareness of the possible link between poor tolerance of a given drug at a given dose and non-adherence with the prescribed regimen. Altogether, these considerations may enable the most effective use of the drugs we already have.

关键词： Glucocorticoids Donor-specific antibodies Kidney transplantation Mechanistic(mammalian)target of rapamycin inhibitor Mycophenolate mofetil Nonadherence Calcineurin inhibitor Sirolimus

实时热中子成像对多孔水泥基材料水分运动的可视化与量化：理论分析与试验研究

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中国科学：技术科学 2010年第6期40卷 657-665页

作者：张鹏 wittmann F H 赵铁军 LEHMANN E 金祖权青岛理工大学山东省耐久性与可持续发展研究中心青岛266033 弗莱堡Aedificat研究所德国弗莱堡D-79100 Paul Scherrer Institute裂变中子源中心 Villigen PSI瑞士CH-5232

多孔水泥基材料中的水分运动对研究其劣化过程和耐久性非常重要.一些传统的测定水泥基材料中水分运动的方法大都基于材料的质量变化、电学或者核磁共振等特性.本文应用先进的实时热中子成像技术,通过理论分析和试验研究,对水泥基材料中... 详细信息

多孔水泥基材料中的水分运动对研究其劣化过程和耐久性非常重要.一些传统的测定水泥基材料中水分运动的方法大都基于材料的质量变化、电学或者核磁共振等特性.本文应用先进的实时热中子成像技术,通过理论分析和试验研究,对水泥基材料中的水分运动包括水分向内部渗透和向外部扩散进行了可视化再现和定量测定.由于热中子对氢原子强烈的衰减特性,热中子成像表现出对材料中水分存在的高度敏感性.基于点散射函数(PScF)建立了对原始成像所含中子传输信息的定量分析方法.对未开裂和开裂砂浆试件的水分渗透过程以及干燥失水过程进行了实时热中子成像试验.结果显示,热中子成像是可视化观测和定量测定多孔水泥基材料中水分运动特性的有力工具,试验结果将有助于更好地理解水泥基材料的劣化规律以寻求提高其耐久性的措施.

关键词：热中子成像水分运动可视化水分运动量化水分渗透水汽扩散水泥基材料

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冻融和碳化作用对混凝土氯离子侵蚀的影响

东南大学学报（自然科学版） 2006年第S2期36卷 238-242页

作者：张鹏赵铁军郭平功 wittmann Folker H 青岛理工大学土木工程学院青岛266033

对4种不同配比混凝土先后进行冻融循环(0,50,150次)、加速碳化(0,1,2星期)和氯离子侵蚀,以研究冻融、碳化作用对混凝土氯离子侵蚀的影响.通过压汞法和选择电极法分别测定不同作用后混凝土的孔径分布和氯离子含量及其毛细吸收变化情况.... 详细信息

对4种不同配比混凝土先后进行冻融循环(0,50,150次)、加速碳化(0,1,2星期)和氯离子侵蚀,以研究冻融、碳化作用对混凝土氯离子侵蚀的影响.通过压汞法和选择电极法分别测定不同作用后混凝土的孔径分布和氯离子含量及其毛细吸收变化情况.结果表明:冻融循环增大混凝土孔隙率,作为混凝土损伤的动力源,为氯离子侵蚀创造更为有利的条件;冻融次数越多,造成的氯离子侵蚀越严重;碳化反应破坏混凝土基体原有的过滤机制,并促进Friedel盐分解,使氯离子含量增多;冻融与碳化均不同程度增大混凝土毛细吸水性能,两者共同作用较单独作用时的氯离子侵蚀严重得多.对混凝土结构进行耐久性设计和使用寿命预测时,必须考虑和引进冻融、碳化及其他因素的复合作用.

关键词：冻融循环碳化氯离子侵蚀毛细吸收

Meiotic behavior and pollinic viability in bean cultivars

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BIOCELL 2014年第1期38卷 33-38页

作者： Gracieli DALLA NORA Solange Bosio TEDESCO Tamara PASTORI Viviane Dal-Souto FRESCURA Nerinéia Dalfollo RIBEIRO Haywood Dail LAUGHINGHOUSE IV Sidinei JoséLOPES Maria Teresa SCHIFINO-wittmann Laboratory of Cytogenetics and Plant Genotoxicity Department of BiologyCenter for Natural and Exact SciencesFederal University of Santa Maria(UFSM)Rio Grande do SulBrazil

The aims of this study were to determine the meiotic behavior and to estimate pollen grains via-bility in bean(Phaseolus vulgaris L.)*** buds were collected during different developmental stages of the Mesoamerican bean cultivars IAPAR 44,Guapo Brilhante,BRS Expedito,BRS Valente,Guateian 6662 and Pérola,and the Andean bean cultivar Iraí,grown in a *** meiotic index was determined by anther squashing of material fixed in absolute ethanol-glacial acetic acid(3:1)and stained with acetic *** meiotic abnormalities were observed and the meiotic indices were high for all cultivars,indicating that the mismatch generated during crosses is not related to any meiotic *** of pollen viability was made by comparing acetic orcein staining ***’s reactive:pollen viability was high in all cultivars with either stain,but was significantly higher when using the acetic orcein stain(>99%).Though some cultivar showed a significantly smaller pollen size,the range of variation among cultivars was low(means’range 51-66μm).

关键词： Acetic orcein Phaseolus vulgaris pollen Alexander’s reactive