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Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter

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Earth and Planetary Physics 2024年第1期8卷 173-183页

作者： Hyangpyo Kim Hyunju K.Connor Jaewoong Jung Brian M.Walsh David Sibeck Kip D.Kuntz Frederick S.porter Catriana K.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura Michael Collier Space Research Institute Austrian Academy of Sciences8042 GrazAustria Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA National Aeronautics and Space Administration(NASA)Goddard Space Flight Center GreenbeltMaryland 20771USA Astronomy Department University of Maryland College ParkCollege ParkMaryland 20742USA Center for Space Physics Boston UniversityBostonMassachusetts 02215USA Department of Physics and Astronomy Johns Hopkins UniversityBaltimoreMaryland 21218USA Howard University WashingtonDC 20059USA

The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind *** suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray *** this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is *** assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause *** create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson *** then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea *** the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground *** method estimates RS with an accuracy of10 *** accuracy improves for greater solar wind densities and during southward interplanetary magnetic *** method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field ***,the technique will enable quantitative analysis of the magnetopause motion and help reveal the daysi

关键词： soft X-ray magnetopause reconnection low-pass filter LEXI SMILE

Expression of proline-rich Akt-substrate PRAS40 in cell survival pathway and carcinogenesis

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Acta Pharmacologica Sinica 2005年第10期26卷 1253-1258页

作者： Gavin porter Department of Pharmacology Emory University School of Medicine Atlanta GA 30032 USA

Aim: To study the expression of proline-rich Akt-substrate PRAS40 in the cell survival pathway and tumor progression. Methods: The effects of three key kinase inhibitors on PRAS40 activity in the cell survival pathway, serum withdrawal,U2O2and overexpression of Akt were tested. The expression of PRAS40, Akt, Raf and 14-3-3 in normal cells and cancer cell lines was determined by Western blot. Results: The PI3K inhibitors worthmannin and Ly294002, but not rapamycin, completely inhibited the phosphorylation of Akt and PRAS40. The phosphorylation level of Akt decreased after serum withdrawal and treatment with the MEK inhibi tor Uo 126, but increased after treatment with H2O2at low concentration, whereas none of these treatments changed PRAS40 activity. 14-3-3 is a PRAS40 binding protein, and the expression of 14-3-3, like that of PRAS40, was higher in HeLa cells than in HEK293 cells; PRAS40 had a stronger phosphorylation activity in A549 and HeLa cancer cells than in HEK293 normal cells. In the breast cancer model (MCF10A/MCF7) and lung cancer model (BEAS/H1198/H1170) we also found the same result: PRAS40 was constitutively active in H1198/H1170 and MCF7 premalignant and malignant cancer cells, but weakly expressed in MCF10A and BEAS normal cell. We also discussed PRAS40 activity in other NSCLC cell lines. Conclusion: The PI3K-Akt survival pathway is the main pathway that PRAS40 is involved in; PRAS40 is a substrate for Akt, but can also be activated by an Akt independent mechanisms. PRAS40 activation is an early event during breast and lung carcinogenesis.

关键词： PRAS40 PI3K-Akt pathway kinase inhibitors 14-3-3 protein

From filaments to function: The role of the plant actin cytoskeleton in pathogen perception,signaling and immunity

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Journal of Integrative Plant Biology 2016年第4期58卷 299-311页

作者： Katie porter Brad Day Graduate Program in Cell and Molecular Biology Michigan State University Department of Plant Soil and Microbial Sciences Michigan State University Graduate Program in Genetics Michigan State University

The eukaryotic actin cytoskeleton is required for numerous cellular processes, including cell shape, development and movement, gene expression and signal transduction, and response to biotic and abiotic stress. In recent years,research in both plants and animal systems have described a function for actin as the ideal surveillance platform, linking the function and activity of primary physiological processes to the immune system. In this review, we will highlight recent advances that have defined the regulation and breadth of function of the actin cytoskeleton as a network required for defense signaling following pathogen infection. Coupled with an overview of recent work demonstrating specific targeting of the plant actin cytoskeleton by a diversity of pathogens,including bacteria, fungi and viruses, we will highlight the importance of actin as a key signaling hub in plants, one that mediates surveillance of cellular homeostasis and the activation of specific signaling responses following pathogen perception. B4 ased on the studies highlighted herein, we propose a working model that posits changes in actin filament organization is in and of itself a highly specific signal, which induces, regulates and physically directs stimulus-specific signaling processes, most importantly, those associated with response to pathogens.

关键词： Actin cytoskeleton immunity pathogen plant Pseudomonas syringae surveillance

The geology, structure and mineralisation of the Oyu Tolgoi porphyry copper-gold-molybdenum deposits, Mongolia： A review

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Geoscience Frontiers 2016年第3期7卷 375-407页

作者： T.M.(Mike) porter porter CeoConsultancy Ply Ltd. Linden Park 5065 SA Australia

The Oyu Tolgoi cluster of seven porphyry Cu-Au-Mo deposits in southern Mongolia,define a narrow,linear,12 km long,almost continuously mineralised trend,which contains in excess of 42 Mt of Cu and1850 t of Au,and is among the largest high grade porphyry Cu-Au deposits in the *** deposits lie within the Gurvansayhan island-arc terrane,a fault bounded segment of the broader Silurian to Carboniferous Kazakh-Mongol arc,located towards the southern margin of the Central Asian Orogenic Belt,a collage of magmatic arcs that were periodically active from the late Neoproterozoic to PermoTriassic,extending from the Urals Mountains to the Pacific *** at Oyu Tolgoi is associated with multiple,overlapping,intrusions of late Devonian（～372 to 370 Ma） quartzmonzodiorite intruding Devonian（or older） juvenile,probably intra-oceanic arc-related,basaltic lavas and lesser volcaniclastic rocks,unconformably overlain by late Devonian（～370 Ma） basaltic to dacitic pyroclastic and volcano sedimentary *** quartz-monzodiorite intrusions range from earlymineral porphyritic dykes,to larger,linear,syn-,late- and post-mineral dykes and *** was deposited within syn-mineral quartz-monzodiorites,but is dominantly hosted by augite basalts and to a lesser degree by overlying dacitic pyroclastic *** ore deposition,an allochthonous plate of older Devonian（or pre-Devonian） rocks was overthrust and a post-ore biotite granodiorite intruded at～365 *** is characterised by varying,telescoped stages of intrusion and *** A-type quartz veined dykes were followed by Cu-Au mineralisation associated with potassic alteration,mainly K-feldspar in quartz-monzodiorite and biotite-magnetite in basaltic *** reflux of cooled,late-magmatic hydrothermal fluid resulted in intense quartz-sericite retrograde alteration in the upper parts of the main syn-mineral intrusions,and an equivalent chlorite-muscovite/illite-hematite assemblage in bas

关键词： Tectonic setting Porphyry copper-gold-molybdenum deposit High sulphidation Geology Alteration Structure

Regional tectonics, geology, magma chamber processes and mineralisation of the Jinchuan nickel-copper-PGE deposit, Gansu Province, China： A review

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Geoscience Frontiers 2016年第3期7卷 431-451页

作者： T.M. (Mike) porter porter GeoConsultancy Pry Ltd. Linden Park 5065 SA Australia

The Jinchuan Ni-Cu-PGE deposit（〉500 Mt @1.2%Ni,0.7%Cu,～0.4 g/t PGE）,one of the largest magmatic sulphide deposits in the world,is located within the westernmost terrane of the North China *** is hosted within the 6.5 km long,Neoproterozoic（～0.83 Ga） Jinchuan ultramafic intrusion,emplaced as a sill-like body into a Palaeoproterozoic suite of gneisses,migmatites,marbles and amphibolites,below an active intracratonic *** parental magma was high-Mg basalt,generated through melting of subcrustal lithospheric mantle by a mantle plume during the initiation of Rodinia supercontinent *** lower Palaeozoic collision of the exotic Qilian Block with the breakup-related southern margin of the craton accreted a subduction complex,and emplaced voluminous granitic intrusions and foreland basin sequences within the craton,to as far north as *** the Cainozoic,allochthonous lower Palaeozoic rocks were thrust up to 300 km to the northeast over cratonic basement,to within 25 km of the Jinchuan *** Jinchuan ultramafic intrusion was injected into three interconnected sub-chambers,each containing a separate *** essentially comprises an olivine-orthopyroxene-chromite cumulate,with interstitial orthopyroxene,clinopyroxene,plagioclase and phlogopite,and is predominantly composed of lherzolite（～80%）,with an outer rim of olivine pyroxenite and cores of mineralised *** occurs as disseminated and net-textured sulphides,predominantly within the dunite,with lesser,PGE rich lenses,late massive sulphide accumulations,small copper rich pods and limited mineralised diopside skarn in wall rock *** principal ore minerals are pyrrhotite（the dominant sulphide）,pentlandite,chalcopyrite,cubanite,mackinawite and pyrite,with a variety of platinum group minerals and minor *** deposit underwent significant post-magmatic tremolite-actinolite,chlorite,serpentine and magnetite *** volume of thejinchuan intrusion accounts for 〈3%

关键词： Rodinia break-up rifting Plume related Deep staging chamber Olivine-orthopyroxene-chromite cumulate Net textured and disseminated sulphides Post-magmatic alteration

Development of high damage threshold laser-machined apodizers and gain filters for laser applications

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High Power Laser Science and Engineering 2016年第3期4卷 113-119页

作者： Patrick Rambo Jens Schwarz Mark Kimmel John L.porter Sandia National Laboratories

We have developed high damage threshold filters to modify the spatial profile of a high energy laser beam. The filters are formed by laser ablation of a transmissive window. The ablation sites constitute scattering centers which can be filtered in a subsequent spatial filter. By creating the filters in dielectric materials, we see an increased laser-induced damage threshold from previous filters created using ‘metal on glass' lithography.

关键词： apodization laser beam shaping laser micro-machining spatial filtering

TRAINING　OF　AN　ORTHOPEDIC　SURGEON

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中华骨科杂志 1996年第8期 56-59页

作者：ＲｉｃｈａｒｄＷ．Ｐｏｒｔｅｒ

ＴＲＡＩＮＩＮＧＯＦＡＮＯＲＴＨＯＰＥＤＩＣＳＵＲＧＥＯＮＡｓｐｅｅｃｈｇｉｖｅｎａｔｔｈｅ＇９５ＩｎｔｅｒｎａｔｉｏｎａｌＣｏｎｇｒｅｓｏｎＯｒｔｈｏｐｅｄｉｃｓ，Ｑｉｎｇｄａｏ，Ｃｈｉｎａ．ＲｉｃｈａｒｄＷ．Ｐｏ... 详细信息

ＴＲＡＩＮＩＮＧＯＦＡＮＯＲＴＨＯＰＥＤＩＣＳＵＲＧＥＯＮＡｓｐｅｅｃｈｇｉｖｅｎａｔｔｈｅ＇９５ＩｎｔｅｒｎａｔｉｏｎａｌＣｏｎｇｒｅｓｏｎＯｒｔｈｏｐｅｄｉｃｓ，Ｑｉｎｇｄａｏ，Ｃｈｉｎａ．ＲｉｃｈａｒｄＷ．ＰｏｒｔｅｒＡｒａｐｉｄｅｘｐａｎｓｉ...

关键词：矫形外科外科医生创伤 AN OF ORTHOPEDIC SURGEON TRAINING 外科大夫

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奥运会给巴黎留下宝贵遗产

新体育 2024年第9期 16-16页

作者： Catherine porter 不详

在巴黎奥运会闭幕式上,一群法国消防员像杂技演员那样舞动身体,一位音乐家弹奏着垂悬于半空的钢琴,奥运选手们成了舞台中央的主角,与法国电子流行乐队一起狂欢。2024年巴黎奥运以与开始时相似的方式落幕,欢乐的人群制造出喧闹景象,场面... 详细信息

在巴黎奥运会闭幕式上,一群法国消防员像杂技演员那样舞动身体,一位音乐家弹奏着垂悬于半空的钢琴,奥运选手们成了舞台中央的主角,与法国电子流行乐队一起狂欢。2024年巴黎奥运以与开始时相似的方式落幕,欢乐的人群制造出喧闹景象,场面充满了闪光灯、烟雾和烟花等元素。

关键词：奥运选手奥运会杂技演员消防员闪光灯巴黎

Opinion: Agriculture Green Development

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Frontiers of Agricultural Science and Engineering 2020年第1期7卷 117-119页

作者： John R.porter Department of Life Sciences University of CopenhagenDK-1017 Copenhagen KDenmark University of Montpellier 34090 MontpellierFrance

Charles Dickens’novel A Tale of Two Cities begins with the words,"It was the best of times,it was the worst of times,it was the age of wisdom,it was the age of foolishness,it was the epoch of belief,it was the epoch of incredulity."We live in the best of times and simultaneously we live in the worst of times—the best of times because.

关键词： Development Opinion foolishness