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现代雷达 1990年第3期12卷 60-67页

作者： Robert j.sanders 陈能秋 ITT Gilfillan

正确选择结构形式,改进功率分配/合成网络,提高晶体管的功率电平和工作频率,指明了设计先进雷达发射机的方法。

关键词：雷达元器件接收机

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SV2B defines a subpopulation of synaptic vesicles

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journal of Molecular Cell Biology 2023年第9期15卷 1-13页

作者： Isabelle Paulussen Hannes Beckert Timothy FMusial Lena j.Gschossmann julia Wolf Mathieu Schmitt jérôme Clasadonte Georges Mairet-Coello christian Wolff Susanne Schoch Dirk Dietrich Synaptic Neuroscience Team Department of NeurosurgeryUniversity Hospital BonnBonn 53127Germany Synaptic Neuroscience Team Department of NeuropathologyUniversity Hospital BonnBonn 53127Germany Microscopy Core Facility Medical FacultyUniversity of BonnBonn 53127Germany UCB Pharma Braine l’Alleud 1420Belgium

Synaptic vesicles can undergo several modes of exocytosis,endocytosis,and trafficking within individual synapses,and their fates may be linked to different vesicular protein ***,we mapped the intrasynaptic distribution of the synaptic vesicle proteins SV2B and SV2A in glutamatergic synapses of the hippocampus using three-dimensional electron ***2B was almost completely absent from docked vesicles and a distinct cluster of vesicles found near the active *** contrast,SV2A was found in all domains of the synapse and was slightly enriched near the active ***2B and SV2A were found on the membrane in the peri-active zone,suggesting the recycling from both clusters of ***2B knockout mice displayed an increased seizure induction threshold only in a model employing high-frequency *** data show that glutamatergic synapses generate molecularly distinct populations of synaptic vesicles and are able to maintain them at steep spatial *** almost complete absence of SV2B from vesicles at the active zone of wildtype mice may explain why SV2A has been found more important for vesicle release.

关键词： 3D electron microscopy synaptic vesicles synaptic vesicle proteins endocytosis trafficking spatial organization

Mitotic Spindle Organization by the Preprophase Band

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Molecular Plant 2008年第6期1卷 950-960页

作者： j. christian Ambrose Richard Cyr The Pennsylvania State University Department of Biology The Huck Institutes of the Life Sciences Integrative Biosciences Graduate Degree Program PlantPhysiology Program University Park PA 16802 USA Present address: Department of Botany University of British Columbia Vancouver British Columbia V6T 1Z4 Canada

In higher plants, the preprophase band （PPB） of microtubules （MTs） forecasts the cell division site prior to mitosis and specifies the organization of MTs into a bipolar prophase spindle surrounding the nucleus. However, the mechanisms governing this PPB-dependent establishment of bipolarity are unclear. Here, we present evidence from live cell imaging studies that suggest a role for the MTs bridging the PPB and the prophase nucleus in mediating this function. Results from drug treatments, along with genetic evidence from null kinesin plants, suggest that these MTs contribute to the bipolarity, orientation, and position of the prophase spindle. Specifically, the absence of these bridge MTs is associated with lack of bipolarity, while non-uniform distributions of bridge MTs correlate with prophase spindle migration, deformation, and enhanced bipolarity toward the region of highest bridge MT density. This behavior does not require actomyosin-based forces, and is enhanced by suppressing MT dynamics with taxol. These observations occur during late prophase, and are coincident with the gradual closing of annular spindle poles. Based on these data, we describe a hypothetical mechanism for bridge MT-dependent organization of prophase spindles.

关键词： preprophase band mitosis acentrosomal spindle microtubule kinesin ATK5 cytokinesis.

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美国除草剂开发使用概况

世界农药 1982年第6期 7-12页

作者： Howard j.sanders 黄汉生美国《C.&E.N.》编辑部

杂草是农业生产的一个难对付的问题。据美国农业部估计,美国农业因杂草而每年要损失约10％,达120亿美元以上,此外为防止草害每年还要花费62亿美元。因此,杂草每年给美国农业造成的经济损失共达180亿美元以上。估计有1,500种左右的杂草... 详细信息

杂草是农业生产的一个难对付的问题。据美国农业部估计,美国农业因杂草而每年要损失约10％,达120亿美元以上,此外为防止草害每年还要花费62亿美元。因此,杂草每年给美国农业造成的经济损失共达180亿美元以上。估计有1,500种左右的杂草危害于美国农业,差不多每一种主要食用作物都有10～50种的杂草危害。

关键词：除草剂作物作用机制农田农业用地杂草危害美利坚合众国北美洲美国

The nucleolus as a genomic safe harbor for strong gene expression in Nannochloropsis oceanica

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Molecular Plant 2022年第2期15卷 340-353页

作者： christian Südfeld Ana Pozo-Rodríguez Sara A.Manjavacas Díez RenéH.Wijffels Maria j.Barbosa Sarah D'Adamo Wageningen University Bioprocess EngineeringPO Box 166700 AA WageningenNetherlands Faculty of Biosciences and Aquaculture Nord University8049 BodøNorway

Microalgae are used in food and feed,and they are considered a potential feedstock for sustainably pro-duced chemicals and ***,production of microalgal-derived chemicals is not yet economically *** engineering could bridge the gap to industrial application and facilitate the production of novel products from ***,we report the discovery of a novel gene expression system in the oleaginous microalga Nannochloropsis that exploits the highly efficient transcriptional activity of RNA po-lymerase I and an internal ribosome entry site for *** identified the nucleolus as a genomic safe harbor for Pol I transcription and used it to construct transformant strains with consistently strong trans-gene *** new expression system provides an outstanding tool for genetic and metabolic en-gineering of microalgae and thus will probably make substantial contributions to microalgal research.

关键词： Nannochloropsis gene expression nucleolus RNA polymerase I IRES aIRES

Molecular docking study of xylogranatins binding to glycogen synthase kinase-3β

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Digital Chinese Medicine 2022年第1期5卷 9-17页

作者： christian Baillya Gérard Vergoten Scientific Consulting Office OncoWitanWasquehalLille 59290France University of Lille InsermINFINITE-U1286Institut de Chimie Pharmaceutique Albert Lespagnol(ICPAL)Faculty of Pharmacy3 rue du Professeur LaguesseBP-83F-59006LilleFrance

Objective The mangrove tree Xylocarpus granatum ***(***)is a medicinal plant used to treat various diseases in several Asian *** bioactive natural products have been isolated from the plants,particularly several groups of limonoids,including 18 xylogranatins(Xyl-A to R),all of which bear a furyl-δ-lactone core commonly found in *** on a structural analogy with the limonoids obacunone and gedunin,we hypothesized that xylogranatins could target the enzyme glycogen synthase kinase-3β(GSK-3β),a major target for the treatment of neurodegenerative pathologies,viral infections,and *** We investigated the binding of the 18 xylogranatins to GSK-3βusing molecular docking in comparison with two known reference GSK-3βATP-competitive inhibitors,LY2090314 and *** each compound bound to GSK-3β,the empirical energy of interaction(ΔE)was calculated and compared to that obtained with known GSK-3βinhibitors and limonoid triterpenes that target this *** Five compounds were identified as potential GSK-3βbinders,Xyl-A,-C,-j,-N,and-O,for which the calculated empiricalΔE was equivalent to that calculated using the best reference molecule *** best ligand is Xyl-C,which is known to have marked anticancer *** of Xyl-C to the ATP-binding pocket of GSK-3βpositions the furyl-δ-lactone unit deep into the binding-site *** xylogranatin derivatives bearing a central pyridine ring or a compact polycyclic structure are much less adapted for GSK-3β***-binding relationships are *** GSK-3βmay contribute to the anticancer effects of *** *** study paves the way for the identification of other furyl-δ-lactone-containing limonoids as GSK-3βmodulators.

关键词： Natural products Xylocarpus granatum Xylogranatins Glycogen synthase kinase-3β(GSK-3β) Limonoids Cancer Molecular modelling Structure-activity relationship

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Characterization of Compositionally Complex Hydrides in a Metastable Refractory High-Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2023年第7期36卷 1173-1178页

作者： jikui Liu junhua Hou Fengchao An Bingnan Qian christian H.Liebscher Wenjun Lu Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen518055China Max-Planck-Institut Für Eisenforschung Max-Planck-Straße 140237DüsseldorfGermany

Here,we study the hydride formation in a metastable Ti-33Zr-22Hf-11Ta(at.%)refractory high entropy alloy(RHEA).Deviating to non-equiatomic compositions of RHEAs promotes the formation of transformation-induced plasticity where the body-centered cubic phase transforms to hexagonal close-packed(HCP)*** is found that the phase transformation capability assists the hydride formation due to the low solubility of hydrogen within the HCP *** this study,hydrogen is charged via electrochemical polishing and the corresponding phase transformation is activated in the metastable *** newly formed HCP phase interacts with hydrogen to form a face-centered cubic hydride verified by electron energy loss *** work provides a primary exploration of the formation of compositionally complex metal hydrides in the metastable RHEAs,which are potential candidates for future hydrogen storage material design.

关键词： Refractory high entropy alloy Compositionally complex hydrides Electrochemical polishing Phase transformation Scanning transmission electron microscopy(STEM)/electron energy loss spectroscopy(EELS)

Machine Learning Models of Plastic Flow Based on Representation Theory

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Computer Modeling in Engineering & Sciences 2018年第12期117卷 309-342页

作者： R.E.jones j.A.Templeton C.M.sanders j.T.Ostien Sandia National Laboratories P.O.Box 969LivermoreCA 94551USA.

We use machine learning(ML)to infer stress and plastic flow rules using data from representative polycrystalline *** particular,we use so-called deep(multilayer)neural networks(NN)to represent the two response *** ML process does not choose appropriate inputs or outputs,rather it is trained on selected inputs and ***,its discrimination of features is crucially connected to the chosen inputoutput ***,we draw upon classical constitutive modeling to select inputs and enforce well-accepted symmetries and other *** the context of the results of numerous simulations,we discuss the design,stability and accuracy of constitutive NNs trained on typical experimental *** these developments,we enable rapid model building in real-time with experiments,and guide data collection and feature discovery.

关键词： Machine learning constitutive modeling plasticity invariance.

A guide for selecting the appropriate plot design to measure ungulate browsing

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Forest Ecosystems 2023年第6期10卷 732-742页

作者： Suzanne T.S.van Beeck Calkoen jerome Milch Andrea D.Kupferschmid christian Fiderer Marco Heurich Department of Visitor Management and National Park Monitoring Bavarian Forest National ParkFreyunger Straße 294481 GrafenauGermany Wildlife Ecology and Management Albert-Ludwigs-University of FreiburgTennenbacher Str.479106 FreiburgGermany Swiss Federal Research Institute WSL Zürcherstrasse 1118903 BirmensdorfSwitzerland Faculty of Applied Ecology Agricultural Sciences and BiotechnologyInstitute for Forest and Wildlife ManagementCampus EvenstadKoppangNorway

Ungulate browsing often impairs tree regeneration,thus preventing the achievement of economic or conservation *** ungulate management would thus benefit from a practical decision tool that facilitates method selection from a wide range of monitoring methods and indicators currently *** this study,we first provide an overview of the different browsing-impact monitoring methods and indicators currently *** then present a newly developed decision matrix for method evaluation that can assist forest stakeholders in choosing the browsing-impact monitoring method best suited to their needs,based on the selected *** first step involved two separate literature reviews to create an overview of the currently applied methods and to select the indicators best suited for measuring browsing *** types of indicator groups with their respective parameters were considered important for method evaluation:browsing indicators(*** density,browsing incidents),performance indicators(***,expertise)and data quality indicators(*** to measurement errors).Subsequently,all parameters defined within each indicator group were categorised and a grade was assigned to each *** create the final method-indicator matrix,each browsing-impact monitoring method received a grade for each parameter within all indicator groups,reflecting the specific advantages and disadvantages of implementing the respective parameter within a specific *** utility of the matrix in selecting the most suitable monitoring method was then demonstrated using the example of Germany's national *** on the weights added to the method-indicator matrix,as defined by national park representatives,and considering local requirements the nearest-tree method was favoured over the other two *** newly developed matrix provides a more scientific objectification of ungulate browsing-impact measures and can be easily used by forest man

关键词： Ungulate Browsing impact Monitoring Indicator Decision matrix Forest management

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Intraprocedural gastric juice analysis as compared to rapid urease test for real-time detection of Helicobacter pylori

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World journal of Gastroenterology 2023年第10期29卷 1638-1647页

作者： Riccardo Vasapolli Florent Ailloud Sebastian Suerbaum jens Neumann Nadine Koch Lukas Macke jörg Schirra julia Mayerle Peter Malfertheiner christian Schulz Medical DepartmentⅡ University Hospital LMU MunichMunich 81377Germany Deutsches Zentrum für Infektionsforschung Partner Site MunichMunich 81377Germany Max von Pettenkofer Institute Faculty of MedicineLudwig-Maximilians University of MunichMunich 80336Germany National Reference Center for Helicobacter pylori Munich 81377Germany Institute of Pathology Faculty of MedicineLudwig-Maximilians-University of MunichMunich 81377Germany

BACKGROUND Endofaster is an innovative technology that can be combined with upper gastrointestinal endoscopy(UGE)to perform gastric juice analysis and real-time detection of Helicobacter pylori(***).AIM To assess the diagnostic performance of this technology and its impact on the management of *** in the real-life clinical *** Patients undergoing routine UGE were prospectively *** were taken to assess gastric histology according to the updated Sydney system and for rapid urease test(RUT).Gastric juice sampling and analysis was performed using the Endofaster,and the diagnosis of *** was based on real-time ammonium *** detection of *** served as the diagnostic gold standard for comparing Endofaster-based *** diagnosis with RUT-based *** *** A total of 198 patients were prospectively enrolled in an *** diagnostic study by Endofasterbased gastric juice analysis(EGjA)during the *** for RUT and histological assessment were performed on 161 patients(82 men and 79 women,mean age 54.8±19.2 years).*** infection was detected by histology in 47(29.2%)***,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value(NPV)for *** diagnosis by EGjA were 91.5%,93.0%,92.6%,84.3%,and 96.4%,*** patients on treatment with proton pump inhibitors,diagnostic sensitivity was reduced by 27.3%,while specificity and NPV were *** and RUT were comparable in diagnostic performance and highly concordant in *** detection(κ-value=0.85).CONCLUSION Endofaster allows for rapid and highly accurate detection of *** during *** may guide taking additional biopsies for antibiotic susceptibility testing during the same procedure and then selecting an individually tailored eradication regimen.

关键词： Helicobacter pylori diagnostic Chronic gastritis Gastric juice Endofaster Rapid urease test Antimicrobial susceptibility testing