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Plant population and weeds influence stalk insects, soil moisture, and yield in rainfed sunflowers

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Insect Science 2007年第5期14卷 425-435页

作者： j.WWAD A. qureshi PHILLIP W. STAHLMAN j. P. MICHAUD Department of Entomology Kansas State University Agricultural Research Center Hays Kansas USA Department of Agronomy Kansas State University Agricultural Research Center Hays Kansas USA

Insect infestation, soil moisture, and yield were examined in populations of≈33 140 plants/ha （low） and ≈ 40 340 plants/ha （high） of an oilseed sunflower, Helianthus annuus L, cv. ＇ Triumph 660CL＇ with two levels of weediness. Less weedy plots resulted from the application of herbicide combination of S-metolachlor and sulfentrazone, whereas more weedy plots resulted from application of sulfentrazone alone. Among the 12 weed species recorded, neither plant numbers nor biomass differed between crop plant densities. Larvae of the stalk-boring insects Cylindrocopturus adspersus （Coleoptera： Curculionidae） and Mordellistena sp. （Coleoptera： Mordellidae） were less abundant in high density sunflowers, ostensibly due to reduced plant size. However, the same effect was not observed for Dectes texanus （Coleoptera： Cerambycidae） or Pelochrista womanana （Lepidoptera： Tortricidae）, two other stalk-boring insects. Soil moisture was highest in low density and lowest in the high density sunflowers that were less weedy. Stalk circumference, head diameter, and seed weight were reduced for sunflower plants with short interplant distances （mean = 20 cm apart） compared to plants with long interplant distances （mean = 46 cm apart）. These three variables were greater in less weedy plots compared with more weedy plot〉 and positively correlated with interplant distance. Yields on a per-hectare basis paralleled those on a per-plant basis but were not different among treatments. The agronomic implications of planting density are discussed in the context of weed and insect management.

关键词： Cylindrocopturus adspersus Dectes texanus Mordellistena sp. neutron probe Pelochrista womanana plant population soil moisture sunflower yield weed control

A CsI(Tl) detector array used in the experiment of the proton-rich nucleus ^(17)Ne

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Chinese Physics C 2009年第S1期33卷 176-178页

作者：马立英华辉卢飞陈东姜希遥叶沿林江栋兴 qureshi faisal-j.mil School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University

To investigate the configurations of the valence protons in Borromean nucleus 17Ne, a CsI(Tl) detector array, which consists of 9 CsI crystals (26×26×20mm3) coupled with photodiodes, has been successfully used in the 17Ne experiment to measure the energy of protons. In order to find the optimal working conditions and get the best energy resolutions, several technologies (including various wrapping materials, wrapping and coupling methods) have been used. The testing results showed that the best energy resolution of the CsI(Tl) is about 3.3% using the 241Am α-source. The primary testing results with the proton beam were also provided.

关键词： CsI(Tl) energy resolution proton

Differential colonization of wheat cultivars by two biotypes of Russian wheat aphid （Homoptera： Aphididae）

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Insect Science 2005年第5期12卷 341-349页

作者： j.WWAD A. qureshi j.WAHAR L. j.OTI j. P. MICHAUD Department of Entomology Kansas State University Agricultural Research Center Hays Kansas USA

Susceptible and resistance wheat cultivars, Triticum aestivum L, were presented to two biotypes of Russian wheat aphid, Diuraphis noxia （Mordvilko）, in multiple choice tests to assay their relative acceptability as host plants. Both apterae （third and fourth instars） and alate adults were offered plants at the two-leaf stage in different cultivar combinations at 22±1℃ and 16：8 （L： D） hour photoperiod. Apterae were released from Petri dishes in the center of a circle of test plants, whereas alatae dispersed from a mature aphid colony to settle on plants arranged in rows. Both alatae and apterous nymphs of both biotypes readily colonized all cultivars tested：‘2137＇, ‘Akron＇,‘Ankor’,‘ Halt’ ,‘ j.gger’ ,‘ Prairie Red’ , ‘Stanton＇,‘TAM 107＇,‘TAM 110＇,‘Trego＇, ‘ Yuma＇, and ‘Yumar＇. Fewer biotype I apterae responded （settled and fed） in the combination containing more resistant （Dn4- and Dny-expressing） cultivars, compared to the combinations that had fewer. The reverse was true for biotype 2 apterae; more aphids responded in the combination containing the largest number of Dn4 expressing cultivars. Differential colonization of cultivars was observed in only one combination, in which biotype 2 apterae colonized Akron and Yumar in larger numbers than they did Stanton and Yuma. A separate experiment confirmed that, 48 hours after infestation, more biotype 2 apterae abandoned plants of Yuma than plants of Yumar. This differential response was likely due to genetic differences between the two ＇ near isogenic＇ lines that include the lack of Dn4 expression in Yuma. Choice tests with alatae did not result in differential rates of cultivar colonization by either biotype in any combination tested. These results suggest that young wheat plants appear to lack any meaningful antixenosis toward D. noxia, even though the aphids appear to perceive, and sometimes respond to, certain differences in cultivar suitability.

关键词： antixenosis biotypes colonization preference Russian wheat aphid Triticum aestivum

Study of the structure of borromean nucleus ^(17)Ne

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Chinese Physics C 2009年第S1期33卷 170-172页

作者：卢飞华辉叶沿林李智焕江栋兴马立英葛愉成郑涛宋玉收李湘庆 qureshi faisal-j.mil School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University

The 17Ne nucleus is a possible candidate with a two-proton borromean halo structure. Since the theoretical model is diffcult to handle the three-body system, it is diffcult to determine the two-proton halo structure in 17Ne. In the present research, we try to study the breakup reaction of 17Ne. For the Borromean nuclei, one-proton knockout results in an unstable nucleus which is decaying further by proton emission. This process will result in an angular correlation between the direction of the aligned recoiling unstable nucleus and its decay products. The angular correlations can give us information about the configuration of the valence proton in the 17Ne. Furthermore, theoretical calculations indicate that the momentum distributions of 16F c.m are sensitive to the structure of the halo in 17Ne. Thus the measurement of momentum distributions of 16F c.m may also give us conclusive information on the structure of 17Ne. The present experiment has been done at IMP in Lanzhou using the radioactive beam 17Ne at 30.8 MeV/u on a 43mg/cm2 12C target. The data analysis is under procedure and the primary results are provided.

关键词： two-proton halo 17Ne breakup reaction

Nonlinear Landau damping of high frequency waves in non-Maxwellian plasmas

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Chinese Physics B 2013年第11期22卷 385-389页

作者： M.N.S.qureshi Sumbul Sehar j.K.Shi H.A.Shah Department of Physics GC University Center for Space Science and Applied Research Chinese Academy of Sciences

Space plasmas often possess non-Maxwellian distribution functions which have a significant effect on the plasma waves. When a laser or electron beam passes through a dense plasma, hot low density electron populations can be generated to alter the wave damping/growth rate. In this paper, we present theoretical analysis of the nonlinear Landau damping for Langmuir waves in a plasma where two electron populations are found. The results show a marked difference between the Maxwellian and non-Maxwellian instantaneous damping rates when we employ a non-Maxwellian distribution function called the generalized （r, q） distribution function, which is the generalized form of the kappa and Maxwellian distribution functions. In the limiting case of r = 0 and q→∞, it reduces to the classical Maxwellian distribution function, and when r = 0 and q→k ＋1, it reduces to the kappa distribution function.

关键词： nonlinear Landau damping non-Maxwellian distribution function nonlinear Langmuir waves,wave-particle interaction

Effect on Landau damping rates for a non-Maxwellian distribution function consisting of two electron populations

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Chinese Physics B 2013年第3期22卷 358-365页

作者： M.N.S.qureshi S.Sehar H.A.Shah j.B.Cao Space Science Institute Beihang University Department of Physics Government College University

In many physical situations where a laser or electron beam passes through a dense plasma,hot low-density electron populations can be generated,resulting in a particle distribution function consisting of a dense cold population and a small hot *** of such low-density electron distributions can alter the wave damping rate.A kinetic model is employed to study the Landau damping of Langmuir waves when a small hot electron population is present in the dense cold electron population with non-Maxwellian distribution *** of plasma from Maxwellian distributions significantly alters the damping rates as compared to the Maxwellian *** damping is found for highly nonMaxwellian distributions as well as plasmas with a higher density and hot electron *** of weak damping is also established when the distribution contains broadened flat tops at the low energies or tends to be *** results may be applied in both experimental and space physics regimes.

关键词： Landau damping Langmuir waves two electron populations non-Maxwellian distribution function

The Soft X-ray Imager(SXI)on the SMILE Mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sembay A.L.Alme D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont T.Crawford j.P.Breuer T.Buggey G.Butcher R.Canchal j.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi j.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson j.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.j.Hubbard H.j.szenszky M.j.nes T.Kennedy K.Koch-Mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.Martindale j.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel j.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.qureshi W.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit j.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun j.Thornhill W.Thomas K.Ullaland B.Walsh D.Walton C.Wang S.Yang School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK Space Park Leicester University of LeicesterLeicesterLE17RHUK Mullard Space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for Space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria Space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State Key Laboratory of Space Weather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northwestern Switzerland CH-5210 WindischSwitzerland Koegl Space GmbH CH-8157 DielsdorfSwitzerland Space Acoustics GmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland Genov Solutions N-5172 LoddefjordNorway STM Engineering N-5165 LaksevagNorway j.hn Hopkins University Applied Physics Laboratory MD 20723USA NASA/Goddard Space Flight Centre MD 20771USA Center for Space Physics Boston UniversityBostonMA 02215USA Department of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)*** is a j.int science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in *** is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE *** is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s *** provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field *** sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many *** is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States.

关键词： Soft X-ray Imaging micropore optics large area CCD

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利用中高能破碎和敲出反应研究非稳定核结构

原子核物理评论 2010年第4期27卷 390-398页

作者：叶沿林 faisal j.mil-qureshi 楼建玲葛愉成吕林辉曹中鑫肖军李奇特陈天逸杨帆北京大学物理学院和核物理与核技术国家重点实验室北京100871

中高能区的破碎和敲出反应,由于机制相对简单、对核的表面敏感、理论处理比较成熟等原因,在非稳定核的晕结构、壳移动等奇特性质研究中发挥了独到作用。针对次级束流强度较弱、能散较大等特点,实验上发展和应用了逆运动学有效立体角完... 详细信息

中高能区的破碎和敲出反应,由于机制相对简单、对核的表面敏感、理论处理比较成熟等原因,在非稳定核的晕结构、壳移动等奇特性质研究中发挥了独到作用。针对次级束流强度较弱、能散较大等特点,实验上发展和应用了逆运动学有效立体角完全测量、轻重靶结合、高精度消色差磁谱仪、前向中子谱仪、在束γ测量等技术手段,大大提升了实验的探测能力和选择性。从物理问题探索和实验路线演变的角度,回顾了非稳定核破碎和敲出反应的发展过程与启示,并探讨未来的走向。

关键词：破碎反应非稳定核核结构反应机制核探测技术

Optic Neuritis in Acute Neuroborreliosis (Lyme Disease) in the U.S.-Mexican Border: Case Report

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World j.urnal of Neuroscience 2016年第2期6卷 126-130页

作者： Ihtesham A. qureshi Michael F. Maldonado Gustavo j. Rodriguez Salvador Cruz-Flores Alberto Maud Neurology Department Texas Tech University Health Sciences Center El Paso USA Ophthalmology Department Texas Tech University Health Sciences Center El Paso USA

Obj.ctive: We describe a patient diagnosed with acute neuroborreliosis presenting with anterior optic neuritis (papillitis) in a non-endemic region. Case Presentation: A 43-year-old previously healthy right handed man admitted due to an insidious onset of severe headache and spells of ascending paresthesias from his right foot into his right arm and face followed by speech arrest and clumsiness of his right hand. His neurologic exam was significant for somnolence, nuchal rigidity and Kernig and Brudzinski signs were present. MRI of the brain with gadolinium showed diffuse hyperintense signal involving the supra and infratentorial cortical sulci, with associated faint diffuse leptomeningeal enhancement, consistent most likely with diffuse leptomeningoencephalitis. EEG: normal. CSF VDRL was negative. Dilated fundus exam revealed mild optic nerve edema more significant to the left than to the right eye, confirmed and measured by spectral domain OCT (Optical Coherence Tomography). There was an evidence of posterior uveitis with an early vitreous hemorrhage superficial to the left optic nerve. Lyme disease serum antibody (IgM) Immunoblotting was positive in 2 bands confirming the diagnosis of neuroborreliosis. Conclusion: Optic nerve involvement in Lyme disease is an uncommon complication that should be confirmed by specific diagnostic criteria to establish its causal relation.

关键词： Optic Neuritis Lyme Disease Non-Endemic Papillitis