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Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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Matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt M.Gyrdymov S.Zähter P.Tavana M.M.Günther N.Bukharskii N.Borisenko J.jacoby X.F.Shen A.Pukhov N.E.Andreev O.N.Rosmej Faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany Focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany National Research Nuclear University MEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation Moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 MeV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHM of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

Collective Forms and Collective Spaces: A Discussion of Urban Design Thinking and Practice Based on Research in Chinese Cities

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China City Planning Review 2019年第4期28卷 8-17页

作者： Sam jacoby the School of Architecture Royal College of Art

The paper examines how social projects,social spaces,and social realities define three contexts and shifts critical to understanding urban design in China,which are the transformations from collective forms to community building,from government to governance,and from urban versus rural development to urban-rural *** argument presented is that a unique unification of administration,production,and reproduction spaces into one institution,produced collective forms in China,whose collective spaces and collective subjectivities contrast with Western-centric explanations of urban design and urban sociology that depend on abstract notions of the public,public space,community,and place ***,collective forms and collective spaces are defined by concrete activities,interests,and benefits that provide social networks of support and care to clearly identifiable *** collective and the community in China are thus always legibly spatialized and develop in parallel to a socialized model of governance that derives from a“differential mode of association.”This creates a spatialized governmentality,an instrumentalization of spatial design by government that brings spatial and social problems of governance closely together.A brief discussion of the historical formations of these changing contexts is the basis to outlining an interdisciplinary urban design approach that deals with spatial and social environments,practices,and *** paper brings together research conducted in Chinese cities including Wuhan,Beijing,and Shanghai.

关键词： collective forms collective spaces people's commune danwei xiaoqu urban design spatialized governmentality

Temperature and precipitation in Mongolia based on dendroclimatic investigations

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Chinese Science Bulletin 2003年第14期48卷 1474-1479页

作者： G.jacoby N.Pederson R.D'A rrigo Lamont-Doherty Earth Observatory Palisades NY 10964 USALamont-Doherty Earth Observatory Palisades NY 10964 USALamont-Doherty Earth Observatory Palisades NY 10964 USA

Recent tree-ring studies in Mongolia provide evidence of unusual warming that is in agreement with large-scale reconstructed and recorded temperatures for the Northern Hemisphere and the Arctic. One Mongolian proxy record for temperature extends back over 1000 years and several others are over 350 years in length. Precipitation reconstructions based on tree rings reflect recent increases but also indicate that the increases are within the long-term range of variations. Spectral analyses of recorded precipitation data and the reconstructions support the hypotheses of quasi-solar periodicity in precipitation variation, previously suggested by others.

关键词：蒙古年轮气候学温度降雨量古气候气候变化

Value investing or investing in illiquidity?The profitability of contrarian investment strategies, revisited

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Financial Innovation 2017年第1期3卷 494-505页

作者： Aron A.Gottesman Gady jacoby Huijing Li Department of Finance Lubin School of BusinessPace UniversityOne Pace PlazaNew YorkNY 10038USA Department of Accounting and Finance I.H.Asper School of BusinessUniversity of ManitobaR3T5V4WinnipegMBCanada

Background:We investigate whether the success of contrarian investment strategies can be attributed to differences in the relative illiquidity of stocks categorized as value investments versus those categorized as glamour ***:Following Lakonishok et al.(J Financ 49:1541–1578,1994),we assess the illiquidity characteristics of portfolios that underlie contrarian investment strategies that are based on the level of stock’s book to ***:We find strong evidence that those portfolios characterized as value investments are associated with dramatically greater levels of illiquidity than glamour *** further demonstrate that strategies based on the illiquidity in the year prior to portfolio formation result in return characteristic of ostensibly contrarian ***:These results suggest that the higher returns associated with contrarian investment strategies are the result of the higher illiquidity associated with value portfolios and represent compensation that the investor receives for accepting *** also suggest that researchers should be cautious before attributing apparent anomalies to behavior-driven expectational errors rather than to other attributes unrelated to behavior,such as illiquidity.

关键词： Contrarian investment strategies Illiquidity Value portfolios Growth portfolios Book to market ratio

Asymmetric variability between maximum and minimum temperatures in Northeastern Tibetan Plateau:Evidence from tree rings

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Science China Earth Sciences 2008年第1期51卷 41-55页

作者： jacoby GORDON Tree-Ring Laboratory Lamont-Doherty Earth Observatory Columbia University NY 10964 USA

Ecological systems in the headwaters of the Yellow River, characterized by hash natural environmental conditions, are very vulnerable to climatic change. In the most recent decades, this area greatly attracted the public's attention for its more and more deteriorating environmental conditions. Based on tree-ring samples from the Xiqing Mountain and A'nyêmagên Mountains at the headwaters of the Yellow River in the Northeastern Tibetan Plateau, we reconstructed the minimum temperatures in the winter half year over the last 425 years and the maximum temperatures in the summer half year over the past 700 years in this region. The variation of minimum temperature in the winter half year during the time span of 1578―1940 was a relatively stable trend, which was followed by an abrupt warming trend since 1941. However, there is no significant warming trend for the maximum temperature in the summer half year over the 20th century. The asymmetric variation patterns between the minimum and maximum temperatures were observed in this study over the past 425 years. During the past 425 years, there are similar variation patterns between the minimum and maximum temperatures; however, the minimum temperatures vary about 25 years earlier compared to the maximum temperatures. If such a trend of variation patterns between the minimum and maximum temperatures over the past 425 years continues in the future 30 years, the maximum temperature in this region will increase significantly.

关键词： Tibetan Plateau tree-ring minimum temperature maximum temperature asymmetric variability warming trend

Reducing dietary sodium of dairy cows fed a low-roughages diet affect intake and feed efficiency,but not yield

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Animal Nutrition 2023年第1期12卷 1-6页

作者： Yehoshav A.Ben Meir Yoav Shaani Daniel Bikel Yuri Portnik Shamai jacoby Uzi Moallem Joshua Miron Eyal Frank Department of Ruminant Science Institute of Animal ScienceAgricultural Research Organization(ARO)Rishon Lezion 7528809Israel Department of Animal Production Extension ServiceMinistry of AgricultureRishon Lezion 7528809Israel

Wastewater from dairy farms has become a major environmental and economical *** residue in treated and untreated wastewater from dairy farms used for irrigation can lead to soil and groundwater salinization,with the risk of soil *** examined the effect of reducing sodium fed to mid to late lactating cows from 0.61%(high sodium[HS])to 0.45%(low sodium[LS])of dry matter on dry matter intake(DMI),milk and milk-component yields,eating behavior,apparent total track digestibility,feed efficiency,and sodium excretion into the *** randomly assigned 28 multiparous high-yielding(>35 kg milk/d)cows to 1 of 2 treatment groups(LS or HS)in a crossover design,with 7 d of adaptation and 28 d of data *** sodium in the diet reduced sodium intake from 171 to 123 g/d while lowering sodium excreted in the manure by 22%.Energy corrected milk(ECM)yield(37.4 kg/d)and sodium excretion in the milk(33.7 g/d)were similar for both *** DMI of LS cows was lower than that of HS cows(27.3 vs.28 kg/d)and consequently,feed efficiency of the LS cows was higher(1.40 vs.1.35 ECM/DMI).Eating rate,meal and visit frequency,and eating time were similar for both treatments;meal and visit duration were longer for the HS cows,and meal and visit sizes tended to be *** of DM and amylase-treated neutral detergent fiber remained *** on the results of this study,and discussed considerations,we recommend lowering the dietary sodium content for mid to late lactating cows in commercial herds to 0.52%of DM,in order to reduce sodium excretion to the environment via urine.

关键词： Mineral absorption Sodium Eating behavior Environmentally friendly dairy farm

Mitochondrial Composition,Function and Stress Response in Plants

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Journal of Integrative Plant Biology 2012年第11期54卷 887-906页

作者： Richard P. jacoby Lei Li Shaobai Huang Chun Pong Lee A. Harvey Millar Nicolas L. Taylor ARC Centre of Excellence in Plant Energy Biology Centre for Comparative Analysis of Biomolecular Networks (CABiN) MCS Building M316 The University of Western Australia 35 Stirling Highway Crawley WA 6009 Western Australia Australia Department of Plant Sciences University of Oxford South Parks Road Oxford OX1 3RB United Kingdom

The primary function of mitochondria is respiration, where catabolism of substrates is coupled to ATP synthesis via oxidative phosphorylation. In plants, mitochondrial composition is relatively complex and flexible an... 详细信息

关键词： Plant mitochondria respiration oxidative stress electron transport chain complex assembly ROS signaling carbon.

Extended-spectrum β-lactamase controversies

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中国感染与化疗杂志 2006年第6期6卷 361-370页

作者： Georgea.jacoby Lahey Clinic BurlingtonMassachusetts 01805USA

*** 教授毕业于美国哈佛医学院,为国际知名的传染病学、微生物学和免疫学专家,曾长期担任美国麻省总医院传染病科医师,现任麻省 Lahey 医学中心传染病实验室主任,中国感染与化疗杂志特邀编委。长期以来 jacoby 教授对细菌耐药机制有深... 详细信息

*** 教授毕业于美国哈佛医学院,为国际知名的传染病学、微生物学和免疫学专家,曾长期担任美国麻省总医院传染病科医师,现任麻省 Lahey 医学中心传染病实验室主任,中国感染与化疗杂志特邀编委。长期以来 jacoby 教授对细菌耐药机制有深入研究,尤其对细菌(肺炎克雷伯菌、大肠埃希菌等)产生质粒介导的超广谱β内酰胺酶(ESBL)以及喹诺酮类的耐药机制研究。曾发表多篇有关上述专题的权威性论著。此次本刊特邀 jacoby 教授撰写有关 ESBL 的新进展,文中阐述目前 ESBLs 除通常所指质粒介导β内酰胺酶中扩大了酶水解的底物谱导致细菌对头孢噻肟、头孢他啶、氨曲南等抗生素耐药外,还包括许多具有不同特点的β内酰胺酶,其中某些酶产自共生菌。除 ESBL 外,AmpC 酶和各种碳青霉烯β内酰胺酶也可导致细菌对上述抗生素耐药,因此临床微生物实验室准确检出和鉴别各种β内酰胺酶,对于临床选用适宜的抗茵药十分重要。美国 CLSI(过去称为 NCCLS)推荐采用两步法(筛选及确证)检测细菌产 ESBL;但有的学者认为测定抗茵药物对细菌的 MIC,如用药后 T>MIC 在50%以上即可达到满意疗效,无需检测细菌是否产 ESBL。目前认为碳青霉烯类抗生素治疗产 ESBL 菌感染的疗效最为满意,但由此可能引起细菌对该类药物耐药,值得关注。采用大剂量头孢吡肟或哌拉西林-三唑巴坦治疗产ESBL 菌感染是否有效尚有争论,临床上对β内酰胺类最为耐药的菌株往往对几乎所有现用抗菌药耐药。黏菌素(或多黏菌素 B)曾成功的用于治疗此种多重耐药菌感染。此外替莫西林(temocillin,一种对β内酰胺酶稳定的青霉素类)与替加环素(tigecvcline,为米诺环素衍生物)体外对产 ESBL 菌有抗菌作用,但尚无临床研究资料。

关键词： ESBLs lactamase controversies Extended-spectrum 中国感染与化疗杂志 MIC AmpC

大肠埃希菌临床分离株对喹诺酮类抗菌药的质粒介导耐药

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中国感染与化疗杂志 2006年第4期6卷 217-221页

作者：王明贵 JohnH.Tran Georgea.jacoby 张婴元汪复 DavidC.Hooper 复旦大学附属华山医院抗生素研究所上海200040 美国哈佛医学院麻省总医院感染科美国Lahey医学中心感染科

目的了解近年来发现的质粒介导耐药机制在大肠埃希菌临床株对喹诺酮类耐药中所起的作用。方法78株环丙沙星耐药菌株分离自上海5所教学医院。以克隆斑点杂交及Southern杂交方法筛选质粒介导耐药基因qnr；以接合试验了解喹诺酮耐药的可转... 详细信息

目的了解近年来发现的质粒介导耐药机制在大肠埃希菌临床株对喹诺酮类耐药中所起的作用。方法78株环丙沙星耐药菌株分离自上海5所教学医院。以克隆斑点杂交及Southern杂交方法筛选质粒介导耐药基因qnr；以接合试验了解喹诺酮耐药的可转移性；对qnr基因进行序列分析,以引物步移法对qnr周边质粒DNA进行测序、分析。结果78株大肠埃希菌中,6株(7．7%)qnr检测阳性。在6株阳性菌中,喹诺酮耐药性均可通过质粒转移,接合子对环丙沙星的MIC较受体菌上升16～250倍。qnr基因与最早报道的序列一致,qnr位于In4族的Ⅰ类整合子上,本研究中的2个新整合子命名为In36及In37。结论与qnr相关的质粒介导喹诺酮类耐药性在大肠埃希菌临床分离株中有一定程度流行,这可能是我国细菌对喹诺酮类耐药性上升迅速的原因之一。

关键词：大肠埃希菌质粒介导耐药喹诺酮类 qnr