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Kinetic Alfven Waves excited by Cometary Newborn Ions with Large Perpendicular energies

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Plasma Science and Technology 2011年第2期13卷 135-139页

作者： george SAMUeL Devi e SAVITHRI Venugopal CHANDU School of Pure and Applied Physics Mahatma Gandhi University

Stability of the kinetic Alfven wave in a plasma of hydrogen, oxygen and electrons is studied. each species is modeled by drifting ring distributions in the direction parallel to the magnetic field, while in the perpendicular direction the distribution is simulated with a loss cone type distribution obtained through the subtraction of two Maxwellian distributions with different temperatures. It is found that for frequencies ω＊〈 ωcH with ω＊ and ωcH the Doppler shifted and hydrogen ion gyro-frequencies, respectively, the growth rate of the kinetic Alfven wave increases with the increase in propagation angles and density of oxygen ions. On the other hand, for frequencies ω＊〈 ωco with ωco the oxygen ion gyro-frequency the growth rate is independent of the oxygen ion density.

关键词： kinetic Alfven wave stability multi-ion cometary plasma

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H3亚型禽流感流行的潜在危害和防控建议

科学通报 2024年第10期69卷 1315-1319页

作者：刘金华孙洪磊高福中国农业大学动物医学院兽医公共卫生安全全国重点实验室农业农村部禽流感等家禽重大疾病防控重点实验室北京100193 中国科学院微生物研究所病原微生物与免疫学重点实验室北京100101 中国疾病预防控制中心病毒病预防控制所中国国家流感中心北京102206

21世纪短短的20年间,人类已经历了两次大流行传染病,即2009年甲型H1N1大流行流感和2019年新型冠状病毒感染.另外发生了5次世界卫生组织宣布的“全球关注的公共卫生应急事件”,给全球经济发展、社会稳定和人类健康造成了严重危害(https:/... 详细信息

21世纪短短的20年间,人类已经历了两次大流行传染病,即2009年甲型H1N1大流行流感和2019年新型冠状病毒感染.另外发生了5次世界卫生组织宣布的“全球关注的公共卫生应急事件”,给全球经济发展、社会稳定和人类健康造成了严重危害(https://***/emergencies/situations).大流行传染病的频繁出现警示我们,人兽共患性病毒是引发大流行疫病的重要病原.动物源性流感病毒在历史上导致了至少5次流感大流行,尤其是最近几年,动物流感病毒频繁跨种感染人类的现象让人们担忧其可能催生下一次人类流感大流行[1].

关键词：冠状病毒感染流感病毒防控建议禽流感 H3亚型跨种感染动物源性流感大流行

Instantaneous frequency and wave mode identification in a magnetosheath using few spatial points

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Chinese Physics B 2013年第8期22卷 496-501页

作者： Nathaniel e U Beloff N george N J Department of Physics Akwa Ibom State UniversityNigeria University of Sussex Brighton UK

Observational data such as those obtained from the magnetosheath in the downstream of earth＇s bow shock have waveforms that differ from those of sinusoidal signals. In practice, they are not even aggregates of sinusoidal signals. Therefore, the frequency decomposition for the data requires technique that will account for the time-varying features of the data that will lead to deduction of physical meaning of the observations. The combination of empirical mode decompo- sition （eMD） and Hilbert transform has been used for extracting the various contributing oscillatory modes （eMDs） and the instantaneous frequency determination （Hilbert transform） of every physically meaningful mode called intrinsic mode func- tion （IMF）. The resulting instantaneous frequencies are used to determine instantaneous wave vectors. The combination of the instantaneous frequencies and wave vectors is useful in the identification of wave modes based on the characteristics of the waves. The results show that eMD-Hilbert can be more reliable than simple Hilbert transform alone.

关键词： eMD-Hilbert transform instantaneous frequency and wave vector

Late Cryogenian glaciation in South Australia:Fluctuating ice margin and no extreme or rapid post-glacial sea-level rise

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Geoscience Frontiers 2019年第4期10卷 1397-1408页

作者： george e.Williams Victor A.Gostin Department of earth Sciences University of Adelaide

Postulated extreme sea-level rise of up to 1-1.5 km with the late Cryogenian Ghaub deglaciation in Namibia is contentious,as is the great rapidity(<104 yr)of the sea-level *** extreme glacioeustatic events,if real,wou... 详细信息

Postulated extreme sea-level rise of up to 1-1.5 km with the late Cryogenian Ghaub deglaciation in Namibia is contentious,as is the great rapidity(e sea-level *** extreme glacioeustatic events,if real,would have been global and affected all *** South Australia,up to six glacial advances and retreats during the late Cryogenian elatina glaciation indicate a fluctuating ice *** latter stage of the elatina glaciation and the immediate post-glacial environment are examined here for evidence of extreme and rapid sea-level *** the central Adelaide Rift Complex,diamictite with faceted and striated clasts occurs at the top of the elatina Formationeneath the early ediacaran Nuccaleena Formation’cap carbonate’.One hundred kilometres to the south,~30 m of siltstone and sandstone followed by^6 m of clast-poor diamictite with clasts 10+cm long occur between tidal rhythmites and the cap *** hundred kilo metres further south,~70 m of siltsto ne,dolo mitic siltstone and minor dolomite separate tidal rhythmites and early ediacaran *** the rhythmites were deposited during a high stand(interstadial or interglacial),not during post-glacial sea-level ***-generated erosional surfaces within tidal rhythmites at Warren Gorge indicate intermittent rhythmite deposition,and water depth and other palaeoenvironmental factors are uncertain,casting doubt on a published estimate of rapid sea-level rise during rhythmite *** lack of late Cryogenian deeply incised valleys and thick valley-fill deposits in South Australia and central Australia argues against extreme sea-level variations.A hiatus occurred between elatina deglaciation and deposition of the Nuccaleena cap carbonate,and three palaeomagnetic polarity chrons identified in the cap carbonate imply slow deposition spanning 10^5-10^6 *** is supported by independent evidence from magnetic chronostratigraphy for ediacaran strata in South Australia and Califo

关键词： Late Cryogenian glaciation Sea level Adelaide Rift Complex elatina Formation Nuccaleena Formation

elimination of Quench Cracking by Controlling Agitation Uniformity

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材料热处理学报 2004年第5期25卷 457-461页

作者： CANALe Lauralice C.F TOTTeN george e Departamento de Materials Automobilistica e Aerondutica da EESC da Universidade de Sao Paulo - USP Sao Carlos SP BrazilPortland State University USA

Uniform agitation of the quenchant is a critically important control parameter in optimizing distortion control and reducing steel cracking. Quenching with ultrasonic agitation or in the presence of electrical and magnetic fields provide uniform agitation leading to improved uniformity of the stress fields within the metal not readily achievable with more traditional agitation methods such as propeller pumps and sprays. These methods provide the additional potential advantage of varying agitation throughout the cooling cycle to achieve a wide range of cooling profiles not readily achievable with quenchants and more traditional agitation systems currently in use.

关键词：热处理淬火裂纹搅拌均匀性超声搅拌

柴达木盆地东部基底花岗岩类岩浆活动的化学地球动力学

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地质学报 2011年第2期85卷 157-171页

作者：陈宣华尹安 George.gehrels 李丽蒋荣宝国土资源部新构造运动与地质灾害重点实验室北京100081 中国地质科学院地质力学研究所北京100081 Department of earth and Space Sciences University of CaliforniaLos Angeles Department of Geosciences University of Arizona

柴达木盆地东部是连接秦岭、祁连、昆仑三大造山带的关键构造部位,发育了以晚二叠世—中三叠世(P-T)花岗岩类为主的古特提斯域深成岩浆活动。岩石地球化学分析表明,柴达木盆地东部基底P-T花岗岩类形成于大洋环境,主要为I型花岗岩类。该... 详细信息

柴达木盆地东部是连接秦岭、祁连、昆仑三大造山带的关键构造部位,发育了以晚二叠世—中三叠世(P-T)花岗岩类为主的古特提斯域深成岩浆活动。岩石地球化学分析表明,柴达木盆地东部基底P-T花岗岩类形成于大洋环境,主要为I型花岗岩类。该期花岗岩类可分为两个时间演化系列,早期为钾长花岗岩—花岗闪长岩—英云闪长岩—闪长岩系列,晚期为碱性花岗岩—钾长花岗岩—花岗闪长岩系列,均具有与经典的鲍文反应系列相反(即反鲍文系列)的演化趋势,反映了深成岩浆的动态混合作用模式。Nd-Sr-Pb-O同位素组成特征说明,柴达木盆地东部基底P-T花岗岩类具有年轻地壳的特征,其来源主要与富集地幔eMⅡ源区有关,具明显的造山带与上地壳Pb同位素特征。柴达木盆地东部基底与西秦岭及扬子块体中生代花岗岩类的Pb同位素组成具有相似性,说明了柴达木盆地基底与扬子地块具有亲缘性。研究表明,来自地幔的基性岩浆底侵作用,以及幔源镁铁质岩浆与壳源长英质岩浆之间的混合作用,可能是柴达木盆地东部基底地壳生长的重要方式。

关键词：化学地球动力学深成岩浆活动二叠纪—三叠纪柴达木盆地东部秦-祁-昆接合带

Polyethylene glycol fusion repair of severed sciatic nerves accelerates recovery of nociceptive sensory perceptions in male and female rats of different strains

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Neural Regeneration Research 2025年第09期 2667-2681页

作者： Liwen Zhou Karthik Venkudusamy emily A.Hibbard Yessenia Montoya Alexa Olivarez Cathy Z.Yang Adelaide Leung Varun Gokhale Guhan Periyasamy Zeal Pathak Dale R.Sengelaub george D.Bittner Department of Neuroscience University of Texas Program in Neuroscience Indiana University Department of Molecular Biosciences University of Texas

Successful polyethylene glycol fusion(PeG-fusion) of severed axons following peripheral nerve injuries for PeG-fused axons has been reported to:(1) rapidly restore electrophysiological continuity;(2) prevent distal Wallerian Degeneration and maintain their myelin sheaths;(3) promote primarily motor,voluntary behavioral recoveries as assessed by the Sciatic Functional Index;and,(4) rapidly produce correct and incorrect connections in many possible combinations that produce rapid and extensive recovery of functional peripheral nervous system/central nervous system connections and reflex(e.g.,toe twitch) or voluntary *** preceding companion paper describes sensory terminal field reo rganization following PeG-fusion repair of sciatic nerve transections or ablations;howeve r,sensory behavioral recovery has not been explicitly explored following PeG-fusion *** the current study,we confirmed the success of PeG-fusion surgeries according to criteria(1-3) above and more extensively investigated whether PeG-fusion enhanced mechanical nociceptive recovery following sciatic transection in male and female outbred Sprague-Dawley and inbred Lewis *** nociceptive responses were assessed by measuring withdrawal thresholds using von Frey filaments on the dorsal and midplantar regions of the *** von Frey filament tests were a more reliable method than plantar von Frey filament tests to assess mechanical nociceptive sensitivity following sciatic nerve *** withdrawal thresholds of the sciatic-mediated lateral dorsal region differed significantly across strain but not *** thresholds did not change significantly from baseline in chronic Unoperated and Sham-operated *** sciatic transection,all rats exhibited severe hyposensitivity to stimuli at the lateral dorsal region of the hindpaw ipsilateral to the ***,PeG-fused rats exhibited significantly earlier return to baseline withdrawal thresholds than N

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Shuram-Wonoka carbon isotope excursion:ediacaran revolution in the world ocean's meridional overturning circulation

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Geoscience Frontiers 2018年第2期9卷 391-402页

作者： george e.Williams Phillip W.Schmidt Department of earth Sciences University of Adelaide Magneticearth

The late ediacaran Shuram-Wonoka excursion, with δ^(13)C_(carb) values as low as-12‰(PDB) in marineshelf deposits and spanning up to 10 Myr, is the deepest and most protracted δ^(13)C_(carb) negative anomaly recognised in earth history. The excursion formed on at least four continents in low(≤32°) palaeolatitudes, and in China is associated with a major phosphogenic event. Global and intrabasinal correlation, magnetostratigraphy, isotope conglomerate tests and further geochemical data are consistent with a primary or syn-depositional origin for the excursion. Continental-margin phosphorites are generated by oceanic upwelling driven by surface winds, and δ^(13)C_(carb) negative anomalies are explicable by oceanic upwelling of 13 C-depleted deep oceanic waters, arguing that a feature common to these exceptional ediacaran events was unprecedented perturbation of the world ocean. These events occurred during the transition from an alien Proterozoic world marked by low-palaeolatitude glaciation near sea level and strong seasonality to the familiar Phanerozoic earth with circum-polar glaciation and temperate climate, suggesting that the Shuram-Wonoka excursion is related to this profound change in earth's climate system. Of various hypotheses for Proterozoic low-palaeolatitude glaciation, only the high obliquity(>54°) hypothesis, which posits secular decrease in obliquity to near the present-day value(23.5°) during the ediacaran, predicts an unparalleled revolution in the ediacaran world ocean. The obliquity controls the sense of the world ocean's meridional overturning circulation, which today is driven by the sinking of cold, dense water at the poles and upwelling driven by zonal surface *** the decreasing obliquity passed the critical value of 54° during the ediacaran the meridional temperature gradient reversed, with the equator becoming warmer than the poles and Hadley lowlatitude(eric zonal circulation reversing. This reversal of the temperat

关键词： ediacaran Shuram-Wonoka carbon isotope excursion Oceanic meridional circulation Atmospheric circulation Proterozoic paleoclimate Obliquity of the ecliptic

Design of Industrial Quenching Processes

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材料热处理学报 2004年第5期25卷 527-530页

作者： Nikolai. I. KOBASKO george .e. TOTTeN Intensive Technologies Ltd Kiev UKRAINEG.E.Totten & Associate LLC Seattle USA

The method of designing industrial processes of quench cooling, in particular, the speed of the conveyor movement with regard to shape and sizes of parts to be quenched, thermal and physical properties of material and cooling capacity of quenchants has been developed. The suggested designing method and databases are the basis for the complete automation of industrial processes of quench cooling, especially for continuous conveyor lines, with the purpose of making high-strength materials. The process is controlled by infrared technique.

关键词：淬火速度控制数据库冷却能力质量控制