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Catalytic Asymmetric[3+2]Cycloaddition of Exocyclic Enol Ethers for the Synthesis of Spiroketals

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Precision Chemistry 2023年第7期1卷 423-428页

作者： Fengcai Zhang Yuqiao Zhou hansen Zhao Long Chen weidi Cao Xiaoming Feng key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China

An efficient synthesis of chiral benzannulated spiroketals via catalytic asymmetric[3+2]cycloaddition of exocyclic enol ethers with p-quinones was *** transformation was enabled by a chiral N,N′-dioxides/Tm^(Ⅲ)complex as the Lewis acid catalyst and afforded a series of enantiomerically enriched benzannulated spiroketal derivatives in good yields(up to 99%)and enantioselectivities(up to 98%ee).Topographic steric maps and distribution of the buried volumes of the catalysts via Cavallo’s SambVca 2 tool were used to elucidate the enantioinduction raised by the ligands and the metal ions.

关键词： asymmetric catalysis [3+2]-cycloaddition spiroketals exocyclic enol ethers quinones

精细农业机械化作物生产计算机集成技术(英文)

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农业工程学报 2006年第11期22卷 152-159页

作者：何勇张勤 Alan hansen Noboru Noguchi Beom-soo Shin 浙江大学生物系统工程与食品科学学院杭州310029 美国伊利诺依大学农业与生物工程系厄尔巴纳il61801 日本北海道大学农业研究生院韩国江原道大学农业工程系

介绍了一项适用于精细农业机械化的新技术计算机集成作物生产技术(CCP)。该技术融合信息采集、网络通讯、数据处理、过程决策、自动执行等功能,能有效地完成作物生产的精确机械化作业。计算机集成作物生产技术的3个主要功能是先根据需... 详细信息

介绍了一项适用于精细农业机械化的新技术计算机集成作物生产技术(CCP)。该技术融合信息采集、网络通讯、数据处理、过程决策、自动执行等功能,能有效地完成作物生产的精确机械化作业。计算机集成作物生产技术的3个主要功能是先根据需要实时采集传感数据,然后根据传感信息构建合理的行动决策,最后将传递上述决策并付诸实施。为了说明CCP的工作原理和结构设计,介绍了由伊利诺依大学机械电子系统实验室设计开发的CCP技术系统的关键功能。研究结果表明,在车辆自动导航,主从机械控制,在线式变量作业等利用农业机械实施田间作物生产作业的领域,有必要在农业机械上集成CCP技术,使机械自动地完成各项最优化项目作业。最后,根据以往工作中的经验,简要讨论了目前CPP技术发展所面临的问题和挑战。

关键词：精细农业计算机集成作物生产机械电子信息采集网络自动化

Growth trends and environmental drivers of major tree species of the northern hardwood forest of eastern North America

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Journal of Forestry Research 2023年第1期34卷 37-50页

作者： Rebecca L.Stern Paul G.Schaberg Shelly A.Rayback Christopher F.hansen Paula F.Murakami Gary J.Hawley Rubenstein School of Environment and Natural Resources The University of VermontBurlingtonVT 05405USA ERM MalvernPA 19355USA Forest Service United States Department of AgricultureNorthern Research StationBurlingtonVT 05405USA Department of Geography The University of VermontBurlingtonVT 05405USA

The future health and productivity of tree species in the northern hardwood forest of eastern North America are uncertain considering changes in climate and pollution loading *** better understand the trajectory of the northern hardwood forest,we studied the growth of three tree species emblematic of it:sugar maple(Acer saccharum Marsh),American beech(Fagus grandifolia Ehrh.),and yellow birch(Betula alleghaniensis Britton),plus a fourth species,red maple(Acer rubrum L.),whose abundance has increased in the *** also analyzed the link between growth and several factors for690 trees in 45 plots throughout Vermont,USA:tree age and size,site elevation,and climate and acid deposition *** their chronologies(1945-2014),all four species exhibited increasing growth followed by plateaued growth indicative of a maturing *** all species,summer moisture was positively correlated with growth,summer temperature was negatively associated with growth,and winter moisture or snow were positively correlated with *** last association was expected for sugar ***,our data suggest that winter snowpack may be more broadly relevant in sustaining tree growth in a region where snow has historically insulated the soil from freezing that can damage roots and lead to reduced aboveground *** of pollution deposition were also correlated with growth for all species except American beech—a species with documented tolerance to pollutant *** the four species studied,red maple had the fewest associations with environmental variables,which suggests that it may be less susceptible to growth reductions as the climate changes.

关键词： Climate change Sugar maple Yellow birch American beech Red maple

Better parameters of ventilation-CO2 output relationship predict death in CHF patients

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中国应用生理学杂志 2015年第6期31卷 508-516页

作者： You-xiu YAO Xing-guo SUN Zhe ZHENG Gui-zhi wANG James E. hansen william w.Stringer karlman wasserman Sheng-shou HU State key Laboratory of Cardiovascular Disease Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China Peking University Third Hospital Beijing 100191 China Respiratory and Critical Care Physiology and Medicine Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Cente St. John's Cardiovascular Research Center Torrance CA 90502 USA Department of Anesthesiology Weifang Medical College Weifang 261061 China

Objective: Measures of ventilation-co_2 output relationship have been shown to be more prognostic than peak O_2 uptake in assessing life expectancy in patients with chronic heart failure(CHF). Because both the ratios(V4e/V4co_2) and slopes(V4e-vs-V4co_2) of ventilation-co_2 output of differing durations can be used, we aim to ascertain which measurements best predicted CHF life expectancy. Methods: Two hundred and seventy-one CHF patients with NYHA class II-IV underwent incremental cardiopulmonary exercise testing(CPET) and were followed-up for a median duration of 479 days. Four different linear regression V4e-vsV4co_2 slopes were calculated from warm-up exercise onset to: 180 s, anaerobic threshold(AT), ventilatory compensation point(VCP); and peak exercise. Five V4e/V4co_2 ratios were calculated for the following durations: rest(120 s), warm-up(30 s), AT(60 s), lowest value(90 s), and peak exercise(30 s). Death or heart transplant were considered end-points. Multiple statistical analyses were performed. Results: CHF patients had high lowest V4e/V4co_2(41.0±9.2, 141±30%pred), high V4e/V4co_2 at AT(42.5±10.4, 145±35%pred), and high V4e-vs-V4co_2 slope to VCP(37.6±12.1, 126±41%pred). The best predictor of death was a higher lowest V4e/V4co_2(≥42, ≥141%pred), whereas the V4e-vs-V4co_2 slope to VCP was less variable than other slopes. For death prognosis in 6 months, %pred values were superior: for longer times, absolute values were superior. Conclusion: The increased lowest V4e/V4co_2 ratio easily identifiable and simply measured during exercise, is the best measurement to assess the ventilation-co_2 output relationship in prognosticating death in CHF patients.

关键词：参数预测二氧化碳 CHF 死亡通气患者输出运动试验

Stellar interiors 2ed.

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SUPPLIER PERSPECTIVE kilned Versus Roasted: A Differentiation of Caramelized Specialty Malts

丛书名： Astronomy and astrophysics library

2004年

作者： Carl J. hansen Steven D kawaler Virginia Trimble

来源：畅想之星图书光盘版（南... 评论

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中外酒业 2019年第13期 63-68页

作者： Cassandra Liscomb Robert hansen Briess Malt & Ingredients Co.

"The term ucaramel malt” is used worldwide to describe a specialty malt that exhibits at least some degree of caramelization. The exact methods of caramel malt production are proprietary to the maltsters that make them, but these specialty malts are generally produced by means of drying green malt on a kiln or in a roaster. This article will provide readers with a clear understanding of the physical, sensorial, and fimctional differences that distinguish kilned and roasted caramel malts from one another.

关键词： Caramelized Specialty Malts Differentiation term ucaramel malt

Three-dimensional structures of virulence proteins of Legionella establish targets for new antibacterials

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微生物与感染 2012年第1期7卷 2-12页

作者： Guido hansen Rolf Hilgenfeld Institute of Biochemistry Center for Structural and Cell Biology in MedicineUniversity of LübeckLübeck 23538Germany German Centre for Infection Research(DZIF) University of LübeckLübeck 23538Germany Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China Laboratory for Structural Biology of Infection and Inflammation c/o DESYHamburg 22603Germany

Legionella pneumophila,the causative agent of Legionnaires' disease,has been recognized as a major health problem responsible for an estimated number of 15 000-30 000 cases of severe pneumonia per year in Germany *** of the high clinical relevance,many aspects of the intracellular life cycle of Legionella,especially details on interactions with host cells,are not well *** information on virulence proteins helps unravel basal pathogenicity mechanisms and is a prerequisite for the rational development of effective drug *** we discuss structures of three important virulence proteins of Legionella that have been determined in our *** structure of the macrophage infectivity potentiator(Mip) protein of Legionella pneumophila is the first of a novel subgroup within the family of Fk506-binding protein(FkBP) peptidyl-prolyl cis/trans *** the basis of the Mip structure,promising antibacterial agents are being ***,structures of two equally exciting Legionella proteins have been *** ferrous iron transport protein FeoB is a transmembrane protein responsible for Fe2+ aquisition after entry of the pathogen into the host *** structure of the cytoplasmic domain of FeoB provides insights into the family of prokaryotic G proteins and allows a detailed comparison with structures of related ***,the characterization of DegQ,a periplasmatic chaperone-protease involved in protein quality control represents an intriguing example of how enzymatic activity is regulated by oligomerization as well as by an intrinsic loop activation cascade,depending on subtle conformational rearrangements.

关键词：摘要编辑部编辑工作读者

A FAIR-compliant parts catalogue for genome engineering and expression control in Saccharomyces cerevisiae

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Synthetic and Systems Biotechnology 2022年第2期7卷 657-663页

作者： Vasil D’Ambrosio Lea G.hansen Jie Zhang Emil D.Jensen Dushica Arsovska Marcos Laloux Tadas Jakociunas Pernille Hjort Davide De Lucrezia Serena Marletta Jay D.keasling Michael k.Jensen Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKgs.LyngbyDenmark Explora Biotech Srl Italy Joint BioEnergy Institute EmeryvilleCAUSA Biological Systems and Engineering Division Lawrence Berkeley National LaboratoryBerkeleyCAUSA Department of Chemical and Biomolecular Engineering Department of BioengineeringUniversity of CaliforniaBerkeleyCAUSA Center for Synthetic Biochemistry Institute for Synthetic BiologyShenzhen Institutes of Advanced TechnologiesShenzhenChina

The synthetic biology toolkit for baker’s yeast,Saccharomyces cerevisiae,includes extensive genome engineering toolkits and parts ***,with the increasing complexity of engineering tasks and versatile applications of this model eukaryote,there is a continued interest to expand and diversify the rational engineering capabilities in this chassis by FAIR(findable,accessible,interoperable,and reproducible)*** this study,we designed and characterised 41 synthetic guide RNA sequences to expand the CRISPR-based genome engineering capabilities for easy and efficient replacement of genomically encoded ***,we characterize in high temporal resolution 20 native promoters and 18 terminators using fluorescein and LUDOX CL-X as references for GFP expression and OD600 measurements,***,all data and reported analysis is provided in a publicly accessible jupyter notebook providing a tool for researchers with low-coding skills to further explore the generated data as well as a template for researchers to write their own *** expect the data,parts,and databases associated with this study to support a FAIR-compliant resource for further advancing the engineering of yeasts.

关键词： gRNA Promoter Terminator Yeast Standardization

Pringsheim Convergence and the Dirichlet Function

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Advances in Pure Mathematics 2016年第6期6卷 441-445页

作者： Thomas Beatty Bradley hansen Department of Mathematics Florida Gulf Coast University Ft. Myers FL USA

Double sequences have some unexpected properties which derive from the possibility of commuting limit operations. For example, may be defined so that the iterated limits and exist and are equal for all x, and yet the Pringsheim limit does not exist. The sequence is a classic example used to show that the iterated limit of a double sequence of continuous functions may exist, but result in an everywhere discontinuous limit. we explore whether the limit of this sequence in the Pringsheim sense equals the iterated result and derive an interesting property of cosines as a byproduct.

关键词： Convergence Pointwise Limit Double Sequence Pringsheim Dirichlet Function Baire Category Theorem Cosine