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UGT74AF3 enzymes specifically catalyze the glucosylation of 4-hydroxy-2,5-dimethylfuran-3(2H)-one,an important volatile compound in Camellia sinensis

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Horticulture Research 2020年第1期7卷 2433-2443页

作者： Yongxian Chen Xiangyang Guo Ting Gao Na Zhang Xiaochun Wan Wilfried schwab Chuankui Song State Key Laboratory of Tea Plant Biology and Utilization International Joint Laboratory on Tea Chemistry and Health EffectsAnhui Agricultural University230036 HefeiAnhuiP.R.China Biotechnology of Natural Products Technische Universität MünchenLiesel-Beckmann-Str.185354 FreisingGermany

4-Hydroxy-2,5-dimethylfuran-3(2H)-one(HDMF)is an important odorant in some fruits,and is proposed to play a crucial role in the caramel-like notes of some ***,its biosynthesis and metabolism in tea plants are still ***,HDMF glucoside was unambiguously identified as a native metabolite in tea plants.A novel glucosyltransferase UGT74AF3a and its allelic protein UGT74AF3b specifically catalyzed the glucosylation of HDMF and the commercially important structural homologues 2(or 5)-ethyl-4-hydroxy-5(or 2)-methylfuran-3(2H)-one(EHMF)and 4-hydroxy-5-methylfuran-3(2H)-one(HMF)to their correspondingβ-***-directed mutagenesis of UGT74AF3b to introduce a single A456V mutation resulted in improved HDMF and EHMF glucosylation activity and affected the sugar donor preference compared with that of the wild-type control *** accumulation of HDMF glucoside was consistent with the transcript levels of UGT74AF3 in different tea *** addition,transient UGT74AF3a overexpression in tobacco significantly increased the HDMF glucoside contents,and downregulation of UGT74AF3 transcripts in tea leaves significantly reduced the concentration of HDMF glucoside compared with the levels in the *** identification of HDMF glucoside in the tea plant and the discovery of a novel-specific UDP-glucose:HDMF glucosyltransferase in tea plants provide the foundation for improvement of tea flavor and the biotechnological production of HDMF glucoside.

关键词： metabolism volatile sugar

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The Strawberry Fruit Fra a Allergen Functions in Flavonoid Biosynthesis

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Molecular Plant 2010年第1期3卷 113-124页

作者： Cristina Munoz Thomas Hoffmann Nieves Medina Escobar Felix Ludemann Miguel A. Botella Victoriano Valpuesta Wilfried schwab Departamento de Biologia Molecular y Bioquimica Universidad de Malaga 29071 Malaga Spain Biomolecular Food Technology Technische Universit~t M0nchen Hochfeldweg 1 85354 Freising Germany

The strawberry Fra a I allergen is a homolog of the major birch pollen allergen Bet v 1. It is synthesized by red ripe fruits of Fragaria x ananassa while white fruits of a mutant genotype, which is known to be tolerated by individuals affected by allergy, are devoid of it. Proteomic analyses have shown that Fra a 1 is down-regulated in the tolerated white- fruited genotype along with enzymes of the anthocyanin pigment pathway. In this study, we report the spatial and tem- poral expression of three Fra a genes that encode different isoforms, and the transient RNAi-mediated silencing of the Fra a genes in strawberry fruits of the red-fruited cultivar Elsanta with an ihpRNA construct. As a consequence of reduced levels of Fra a mRNAs, fruits were obtained that produced significantly decreased levels of anthocyanins and upstream metabolites. This effect is consistent with the parallel down-regulation of the phenylalanine ammonia lyase （FaPAL） and to a lesser extent of the chalcone synthase （FaCHS） transcript levels also found in these fruits. In naturally occurring white- fruited genotypes of F. chiloensis and F. vesca, Fra a transcript levels are higher than those of the red-fruited varieties, likely to compensate for the low expression levels of FaPAL and FaCHS in these mutant genotypes. The results demonstrate that Fra a expression is directly linked to flavonoid biosynthesis and show that the Fra a allergen has an essential biological function in pigment formation in strawberry fruit.

关键词： Fragaria flavonoid anthocyanin phenylpropanoid allergen pathogenesis-related proteins.

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Risk of conduction disturbances following different transcatheter aortic valve prostheses:the role of aortic valve calcifications

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Journal of Geriatric Cardiology 2022年第3期19卷 167-176页

作者： Francesco Pollari Ferdinand Vogt Irena Großmann Jill Marianowicz Marie Claes Steffen Pfeiffer Johannes schwab Theodor Fischlein Cardiac Surgery Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Cardiology Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Radiology Klinikum NürnbergParacelsus Medical UniversityNurembergGermany

OBJECTIVES To assess the impact of prosthesis choice and aortic valve calcifications on the occurrence of conduction disturb-ances after transcatheter aortic valve implantation(TAVI).METHODS We retrospectively analyzed the preoperative clinical characteristics,electrocardiograms,contrast-enhanced mul-tidetector computed tomography scans and procedural strategies of patients who underwent TAVI in our center between January 2012 and June *** of calcium volume was performed for each aortic cusp above(aortic valve)and below(left ventricular outflow tract,LVOT)the basal *** analysis was performed to evaluate risk factors for the onset of new bundle branch block(BBB),transient and permanent atrioventricular block(tAVB,pAVB).RESULTS A total of 569 patients were included in the *** different prostheses were implanted(Edwards Sapien XT,n=162;Edwards Sapien 3,n=240;Medtronic CoreValve,n=27;Medtronic CoreValve Evolut R,n=21;Symetis Acurate,n=56;Sy-metis Acurate neo,n=63).The logistic regression analysis for BBB showed association with baseline left anterior *** logistic regression for tAVB,found the prior valvuloplasty and the balloon post-dilatation associated with the *** left and right BBB,degree of oversizing,and LVOT calcification beneath the non-coronary cusp were associated with *** the prosthesis model,nor the use of a self-expandable prosthesis showed statistical significance with the above-men-tioned outcomes on univariate *** LVOT calcification beneath the non-coronary cusp,baseline left anterior hemiblock,right BBB,balloon post-dilatation,prior valvuloplasty and oversizing are independently associated with postprocedural conduction disturbances after *** of a self-expandable prosthesis may show a lower incidence of AVB,if applied in lower calcified aortic valves.

关键词： aortic balloon conduction

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Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change

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Journal of Mountain Science 2017年第3期14卷 453-473页

作者： Niels schwab Udo SCHICKHOFF Birgit BURZLE Michael MULLER Jurgen BOHNER Ram Prasad CHAUDHARY Thomas SCHOLTEN Jens OLDELAND CEN Center for Earth System Research and Sustainability Institute of GeographyUniversity of HamburgBundesstrafle 5520146 HamburgGermany Department of Geosciences Chair of Soil Science and CeomorphologyUniversity of TübingenGermany Research Centre for Applied Science and Technology&Central Department of Botany Tribhuvan UniversityNepal Biocentre Klein Flottbek University of HamburgOhnhorststr.1822609 HamburgGermany

Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths （3700-4200 m） at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions （e.g., nutrient and thermal deficits, plant interactions） across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran＇s eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.

关键词： Himalaya Nepal Population structure Rhododendron campanulatum Spatial patterns Species-environment relationships Stand density Variation partitioning

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Inverse Problem on Heat Conduction in Heterogeneous Medium

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American Journal of Computational Mathematics 2014年第1期4卷 30-36页

作者： Albert schwab M.A. Lavrentiev Institute of Hydrodynamics Siberian Branch Russian Academy of Sciences Novosibirsk Russia

Under consideration is a nonclassical stationary problem on heat conduction in a body with the pre-set surface temperature and heat flow. The body contains inclusions at unknown locations and with unknown boundaries. The body and inclusions have different constant thermal conductivities. The author explores the possibility of locating inclusions. The article presents an integral criterion based on which a few statements on identification of inclusions in a body are proved.

关键词： Heat Conduction Inclusions Defect Heterogeneous Medium Inverse Problem

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Adolescent Reproductive Health: Challenges and Change

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Journal of Reproduction and Contraception 2004年第3期15卷 172-180页

作者： Laurie schwab Zabin School of Public Health Johns Hopkins University USA

The field of reproductive health has had long ronnaents in ways that other health fields have not experience negotiating challenging enviperhaps because other health fields usually deal with illness which everyone agrees is not a good thing. Or maybe because we have all been born, we all think we know something about reproduction. Whatever the reason, we have over the years seen bitter political and ideological debates over population and family planning, abortion, the treatment of HIV/AIDS, in vitro fertilization, new contraceptive technologies--and now adolescent reproductive health. We shouldn＇t be surprised. But just as we have had to prevail in those debates in the past, they are crucial today： the numbers of young people entering their reproductive years throughout the world, especially the developing world, make it essential that youth be reached not only with messages and services crafted in the last 40 years but also with new messages, new ideas and new services.

关键词： Adolescent Reproductive Health Challenges and Change

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Opening Address of Annual Meeting 2000 of World Economic Forum

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中国远洋海运 2000年第3期 17-18页

作者： Klaus schwab World Economic Forum Founder and President

We are all here together for the first global Summit of the 21st century —a global gathering bringing together political, business, intellectual and civic leaders to define the new beginnings and to make a positive contribution. "New beginnings: making a difference" is, as you know, the theme of our Annual Meeting. There is one striking feature that differentiates this year’s Annual Meeting from the last ones: at this particular moment, we are not confronted with any overwhelming crisis. You will recall that in 1999 we were deeply worried about the global economic outlook; and two years ago, it was the Asian crisis which was at the centre of our attention. This year, witlhout such a crisis preoccupying our minds, we have even more reasons to look at the truly important fundamental, long-term challenges of our world at the beginning of the new millennium.

关键词： World Opening Address of Annual Meeting 2000 of World Economic Forum

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Anti-microtubule activity of the traditional Chinese medicine herb Northern Ban Lan(Isatis tinctoria)leads to glucobrassicin

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Journal of Integrative Plant Biology 2021年第12期63卷 2058-2074页

作者： Pingyin Guan Jianning Zhou Sergey Girel Xin Zhu Marian schwab Kunxi Zhang Qiyan Wang-Müller Laurent Bigler Peter Nick Molecular Cell Biology Botanical InstituteKarlsruhe Institute of TechnologyFritz-Haber-Weg 4Karlsruhe 76131Germany Department of Chemistry University of ZürichWinterthurerstr.190CH-8057ZurichSwitzerland Research Institute of Organic Agriculture FiBL Ackerstrasse 113CH-5070FrickSwitzerland College of Horticulture China Agricultural UniversityBeijing 100193China Institute of Pharmaceutical Sciences of Western Switzerland University of GenevaRue Michel-Servet 1CH-1211Geneva 4Switzerland Swiss Chinese Herbal Medicine and Functional Food Innovation Center Mainaustrasse 21CH-8046ZurichSwitzerland

Traditional Chinese medicine(TCM)belongs to the most elaborate and extensive systems of plant-based *** herb Northern Ban Lan(Isatis tinctoria)is famous for its antiviral and anti-inflammatory *** numerous components isolated from *** have been characterized so far,their modes of action have remained ***,we show that extracts from *** exert antimicrotubular *** time-lapse microscopy in living tobacco BY-2(Nicotiana tabacum ***2)cellsexpressing greenfluorescentprotein-tubulin,weuse activity-guided fractionation to screen out the biologically active compounds of *** 54 fractions obtained from either leaves or roots of *** by methanol(MeOH/H_(2)O 8:2),or ethyl acetate extraction,one specific methanolic root fraction was selected,because it efficiently and rapidly eliminated *** combination of further purification with ultrahigh-performance liquid chromatography and high-resolution tandem mass spectrometry most of the bioactivity could be assigned to the glucosinolate compound *** can also affect microtubules and induce apoptosis in HeLa *** the light of these findings,the antiviral activity of Northern Ban Lan is discussed in the context of microtubules being hijacked by many viral pathogens for cell-to-cell spread.

关键词： anti-microtubule activity cytoskeleton glucobrassicin high-performance liquid chromatography(HPLC) high-resolution tandem mass spectrometry(HRMS/MS) Isatis tinctoria Northern Ban Lan traditional Chinese medicine(TCM)

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Learn More about Your Data: A Symbolic Regression Knowledge Representation Framework

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International Journal of Intelligence Science 2012年第4期2卷 135-142页

作者： Ingo schwab Norbert Link Karlsruhe University of Applied Sciences Karlsruhe Germany

In this paper, we propose a flexible knowledge representation framework which utilizes Symbolic Regression to learn and mathematical expressions to represent the knowledge to be captured from data. In this approach, learning algorithms are used to generate new insights which can be added to domain knowledge bases supporting again symbolic regression. This is used for the generalization of the well-known regression analysis to fulfill supervised classification. The approach aims to produce a learning model which best separates the class members of a labeled training set. The class boundaries are given by a separation surface which is represented by the level set of a model function. The separation boundary is defined by the respective equation. In our symbolic approach, the learned knowledge model is represented by mathematical formulas and it is composed of an optimum set of expressions of a given superset. We show that this property gives human experts options to gain additional insights into the application domain. Furthermore, the representation in terms of mathematical formulas (e.g., the analytical model and its first and second derivative) adds additional value to the classifier and enables to answer questions, which sub-symbolic classifier approaches cannot. The symbolic representation of the models enables an interpretation by human experts. Existing and previously known expert knowledge can be added to the developed knowledge representation framework or it can be used as constraints. Additionally, the knowledge acquisition framework can be repeated several times. In each step, new insights from the search process can be added to the knowledge base to improve the overall performance of the proposed learning algorithms.

关键词： Classification Symbolic Regression Knowledge Management Data Mining Pattern Recognition

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Amplification of early drought responses caused by volatile cues emitted from neighboring tea plants

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Horticulture Research 2021年第1期8卷 3337-3348页

作者： Jieyang Jin Mingyue Zhao Ting Gao Tingting Jing Na Zhang Jingming Wang Xianchen Zhang Jin Huang Wilfried schwab Chuankui Song State Key Laboratory of Tea Plant Biology and Utilization International Joint Laboratory on Tea Chemistry and Health EffectsAnhui Agricultural University230036 HefeiAnhuiP.R.China Biotechnology Institute Chengdu Newsun Crop Science Co.Ltd610212 ChengduP.R.China Biotechnology of Natural Products Technische Universität MünchenLiesel-Beckmann-Str.185354 FreisingGermany

Plants have developed sophisticated mechanisms to survive in dynamic *** can communicate via volatile organic compounds(VOCs)to warn neighboring plants of *** most cases,VOCs act as positive regulators of plant ***,the communication and role of volatiles in response to drought stress are poorly ***,we showed that tea plants release numerous *** them,methyl salicylate(MeSA),benzyl alcohol,and phenethyl alcohol markedly increased under drought ***,further experiments revealed that drought-induced MeSA lowered the abscisic acid(ABA)content in neighboring plants by reducing 9-cis-epoxycarotenoid dioxygenase(NCED)gene expression,resulting in inhibition of stomatal closure and ultimately decreasing early drought tolerance in neighboring *** application of ABA reduced the wilting of tea plants caused by MeSA *** of Nicotiana benthamiana to MeSA also led to severe wilting,indicating that the ability of drought-induced MeSA to reduce early drought tolerance in neighboring plants may be conserved in other plant *** together,these results provide evidence that drought-induced volatiles can reduce early drought tolerance in neighboring plants and lay a novel theoretical foundation for optimizing plant density and spacing.

关键词： drought neighboring volatile

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