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Recent results of zebra patterns in solar radio bursts

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Research in Astronomy and Astrophysics 2010年第9期10卷 821-866页

作者： Gennady P.chernov Key Laboratory of Solar Activity National Astronomical ObservatoryChinese Academy of Science Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences (IZMIRAN)

This review covers the most recent experimental results and theoretical research on zebra patterns （ZPs） in solar radio bursts. The basic attention is given to events with new peculiar elements of zebra patterns received over the last few years. All new properties are considered in light of both what was known earlier and new theoretical models. Large-scale ZPs consisting of small-scale fiber bursts could be explained by simultaneous inclusion of two mechanisms when whistler waves ＂high- light＂ the levels of double plasma resonance （DPR）. A unique fine structure was observed in the event on 2006 December 13： spikes in absorption formed dark ZP stripes against the absorptive type Ⅲ-like bursts. The spikes in absorption can appear in accordance with well known mechanisms of absorptive bursts. The additional injection of fast particles filled the loss-cone （breaking the loss-cone distribution）, and the generation of the continuum was quenched at these moments. The maximum absorptive effect occurs at the DPR levels. The parameters of millisecond spikes are determined by small dimensions of the particle beams and local scale heights in the radio source. Thus, the DPR model helps to understand severai aspects of unusual elements of ZPs. However, the simultaneous existence of several tens of the DPR levels in the corona is impossible for any realistic profile of the plasma density and magnetic field. Three new theories of ZPs are examined. The formation of eigenmodes of transparency and opac- ity during the propagation of radio waves through regular coronal inhomogeneities is the most natural and promising mechanism. Two other models （nonlinear periodic space - charge waves and scattering of fast protons on ion-sound harmonics） could happen in large radio bursts.

关键词： Sun general -- Sun flare -- Sun radio radiation

Cranial nerve monitoring in endoscopic endonasal surgery of skull base tumors (observing of 23 cases)

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Chinese Neurosurgical Journal 2019年第1期5卷 21-29页

作者： A.N.Shkarubo I.V.chernov A.A.Ogurtsova V.E.chernov O.V.Borisov K.V.Koval D.N.Andreev Department of Neurooncology Federal State Autonomous Institution"N.N.Burdenko National Medical Research Center of Neurosurgery"of the Ministry of Health of the Russian FederationMoscowRussia Department of Neurophysiology Federal State Autonomous Institution"N.N.Burdenko National Medical Research Center of Neurosurgery"of the Ministry of Health of the Russian FederationMoscowRussia Department of Neurosurgery N.N.Burdenko Main Military Clinical Hospital of the Ministry of Defense of the Russian FederationMoscowRussia Laboratory of Molecular Human Genetics Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological AgencyMoscowRussia

Background:Preservation of anatomic integrity and function of the cranial nerves during the removal of skull base tumors is one of the most challenging procedures in endoscopic endonasal surgery.It is possible to use intraoperative mapping and identification of the cranial nerves in order to facilitate their preservation.The purpose of this study was to evaluate the effectiveness of intraoperative trigger electromyography in prevention of iatrogenic damage to the cranial nerves.Methods:Twenty three patients with various skull base tumors(chordomas,neuromas,pituitary adenomas,meningiomas,cholesteatomas)underwent mapping and identification of cranial nerves during tumor removal using the endoscopic endonasal approach in Department of Neurooncology of Federal State Autonomous Institution"N.N.Burdenko National Medical Research Center of Neurosurgery"of the Ministry of Health of the Russian Federation from 2013 to 2018.During the surgical interventions,mapping and identification of the cranial nerves were carried out using electromyography in triggered mode.The effectiveness of the method was evaluated based on a comparison with a control group(41 patients).Results:In the main group of patients,44 nerves were examined during surgery using triggered electromyography.During the study,the III,V,VI,VII,and XII cranial nerves were identified intraoperatively.Postoperative cranial nerve deficiency was observed in 5 patients in the study group and in 13 patients in the control group.The average length of hospitalization was 9 days.Conclusion:We did not receive statistically significant data supporting the fact that intraoperative identification of cranial nerves using trigger electromyography reduces the incidence of postoperative complications in the form of cranial nerve deficits(p=0.56),but the odds ratio(0.6)suggests a less frequent occurrence of complications in the study group.Based on our experience,the trigger electromyography methodology appears quite promising and requires further research.

关键词： Electromyography T-EMG Intraoperative cranial nerve identification Endoscopic endonasal approach Skull base tumor surgery

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The importance of source positions during radio fine structure observations

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Research in Astronomy and Astrophysics 2014年第7期14卷 831-842页

作者： Guennadi P.chernov Yi-Hua Yan Qi-Jun Fu Key Laboratory of Solar Activity National Astronomical ObservatoryChinese Academy of Sciences Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences (IZMIRAN)TroitskMoscow region142190Russia

The measurement of positions and sizes of radio sources in the observations of the fine structure of solar radio bursts is a determining factor for the selection of the radio emission mechanism. The identical parameters describing the radio sources for zebra structures（ZSs） and fiber bursts confirm there is a common mechanism for both structures. It is very important to measure the size of the source in the corona to determine if it is distributed along the height or if it is point-like. In both models of ZSs（the double plasma resonance（DPR） and the whistler model） the source must be distributed along the height, but by contrast to the stationary source in the DPR model, in the whistler model the source should be moving. Moreover, the direction of the space drift of the radio source must correlate with the frequency drift of stripes in the dynamic spectrum. Some models of ZSs require a local source, for example,the models based on the Bernstein modes, or on explosive instability. The selection of the radio emission mechanism for fast broadband pulsations with millisecond duration also depends on the parameters of their radio sources.

关键词： solar flare -- radio emission -- zebra-pattern -- spike-bursts

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俄罗斯高等旅游人才培养现状及其对策

旅游纵览(下半月) 2015年第14期 257-258页

作者： SKAVRONSKAYA LIUBOV chernov VLADSLAV 华南理工大学经济与贸易学院俄罗斯哈巴罗夫斯科市远东国立交通大学国际商务服务及旅游系经济学院

俄罗斯的旅游业发展迅速,旅游人才的培养出现了诸多问题。本文以俄罗斯远东国立交通大学的旅游教育为例,分析俄罗斯旅游人才培养现状,找出人才培养存在的问题,并提出解决方法和对策,希望对俄罗斯旅游教育的理论研究提供帮助。

关键词：俄罗斯交通大学远东旅游旅游人才培养教师培训机制专业课程旅游业旅游产业

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软土地基上地表建筑系统的强震反应(英文)

西北地震学报 2005年第1期27卷 30-35页

作者： POTAPOV V.A. chernov E.A 俄罗斯科学院西伯利亚分院地壳研究所伊尔库茨克格勃64033俄罗斯

本文导出了一种给出相对烈度在lg R^0之间的收敛解(忽略震级)的小震方程式。结合在贝加尔地区岩石抗震特性调查与文字资料和统一理论,使人们可对震源等势面进行评估。确定了在震源区边界处的地震烈度稳定性和弹性波在地壳中的传播,使得... 详细信息

本文导出了一种给出相对烈度在lg R^0之间的收敛解(忽略震级)的小震方程式。结合在贝加尔地区岩石抗震特性调查与文字资料和统一理论,使人们可对震源等势面进行评估。确定了在震源区边界处的地震烈度稳定性和弹性波在地壳中的传播,使得推导出从地震主要参数震级向随震中距不同的烈度定量计算的转换成为可能。获得了烈度(能通量的密度)对距离的双线性相关,给出了能通量密度和相对烈度之间的关系。求出了取决于地表建筑地基的物理特性的振动载荷烈度。在地震学角度,这种强震的定量预测方法是一种提供详细地震区划和场地小区划的可能手段之一。

关键词：地震烈度地震反应抗震

Envelope Soliton in Solar Radio Emission

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Chinese Physics Letters 2000年第5期17卷 355-357页

作者：王德焴 G.P.chernov Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 National Astronomical Observatories Chinese Academy of Sciences IZMIRAN 142092 TroitaskMoscow RegionRussia

Several envelope soliton fine structures have been observed in solar radio metric-wave emission.present a model of longitudinal modulational instability to explain these fine structures.It is found that this instability can only occur in the condition of sound velocity being larger than Alfvin velocity in corona.Therefore,the envelope soliton fine structures should display in the coronal region with high temperature and low magnetic 6eld,which corresponds to the solar radio emission in the region of meter and decameter wavelength.

关键词： soliton envelope Soliton

Flare evolution and polarization changes in fine structures of solar radio emission in the 2013 April 11 event

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Research in Astronomy and Astrophysics 2016年第2期16卷 69-80页

作者： Gennady chernov Robert Sych Bao-Lin Tan Yi-Hua Yan Cheng-Ming Tan Qi-Jun Fu Marian Karlicky Valery Fomichev Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences(IZMIRAN)TroitskMoscow region142190Russia Yunnan Observatories Chinese Academy of SciencesKunming 650011China Institute of Solar-Terrestrial Physics Russian Academy of SciencesSiberian BranchIrkutsk 664033Russia Astronomical Institute of the Academy of Sciences of the Czech Republic Ondrejov 15165Czech Republic

The measurement of positions and sizes of radio sources in observations is important for un- derstanding of the flare evolution. For the first time, solar radio spectral fine structures in an M6.5 flare that occurred on 2013 April 11 were observed simultaneously by several radio instruments at four different observatories： Chinese Solar Broadband Radio Spectrometer at Huairou （SBRS/Huairou）, Ondrejov Radio Spectrograph in the Czech Republic （ORSC/Ondrejov）, Badary Broadband Microwave Spectropolarimeter （BMS/Irkutsk）, and spectrograph/IZMIRAN （Moscow, Troitsk）. The fine structures included microwave zebra patterns （ZPs）, fast pulsations and fiber bursts. They were observed during the flare brightening lo- cated at the tops of a loop arcade as shown in images taken by the extreme ultraviolet （EUV） telescope onboard NASA＇s satellite Solar Dynamics Observatory （SDO）. The flare occurred at 06：58-07：26 UT in solar active region NOAA 11719 located close to the solar disk center. ZPs appeared near high frequency boundaries of the pulsations, and their spectra observed in Huairou and Ondrejov agreed with each other in terms of details. At the beginning of the flare＇s impulsive phase, a strong narrowband ZP burst occurred with a moderate left-handed circular polarization. Then a series of pulsations and ZPs were observed in almost unpolarized emission. After 07：00 UT a ZP appeared with a moderate right-handed polarization. In the flare decay phase （at about 07：25 UT）, ZPs and fiber bursts become strongly right-hand polarized. BMS/Irkutsk spectral observations indicated that the background emission showed a left-handed circular polarization （similar to SBRS/Huairou spectra around 3 GHz）. However, the fine structure appeared in the right-handed polarization. The dynamics of the polarization was associated with the motion of the flare ex- citer, which was observed in EUV images at 171 A and 131 A by the SDO Atmospheric Imaging Assembly （AIA）. Combining magnetograms observed by the SDO Helioseismic and Magnetic Imager （HMI） wi

关键词： Sun activity -- Sun flares -- Sun particle emission -- Sun radio radiation -- zebra-pattern

Endoscopic endonasal transclival removal of tumors of the clivus and anterior region of the posterior cranial fossa (results of surgical treatment of 140 patients)

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Chinese Neurosurgical Journal 2018年第4期4卷 219-232页

作者： Alexey N. Shkarubo Konstantin V. Koval Ilia V. chernov Dmitry N. Andreev Alexey B. Kurnosov Andrey A. Panteleyev Federal State Autonomous Institution N.N. Burdenko National Medical Research Center of Neurosurgery of the Ministry of Health of the Russian Federation (N.N. Burdenko NMRCN) 4-ya Tverskaya-YAmskaya street 16 Moscow Russian Federation

Background: Until recently, tumors of the clivus and the anterior region of the posterior cranial fossa were considered extremely difficult to access and often inoperable using standard transcranial approaches. With the introduction into the neurosurgical practice of minimally invasive methods utilizing endoscopic techniques, it became possible to effectively remove hard-to-reach tumors, including central tumors of the anterior region of the posterior cranial fossa. Methods: From 2008 to the present time, the inpatient institution has operated on 140 patients with various tumors of the base of the skull, localized to the clivus and anterior region of the posterior cranial fossa (65 men and 75 women). The age of patients ranged from 3 to 74 years. Tumor distribution according to the histopathological features was as follows: chordomas, 103 (73.57%);meningiomas, 12 (8.57%);pituitary adenomas, 9 (6.43%);fibrous dysplasia, 4 (2.86%);cholesteatoma, 3 (2.14%);craniopharyngiomas, 2 (1.43%);plasmacytomas, 2 (1.43%);and other tumors (giant cell tumor, neurohypophyseal glioma, osteoma, carcinoid, chondroma), 5 (3.57%). The tumors had the following size distribution: giant (more than 60 mm), 35 (25%);large (35–59 mm), 83 (59.3%);medium (21–35 mm), 21 (15%);and small (less than 20 mm), 1 (0.7%). In 11 cases, intraoperative monitoring of the cranial nerves was performed (21 cranial nerves were identified). Results: Upper, middle, and lower transclival approaches provide access to the anterior surface of the upper, middle, and lower neurovascular complexes of the posterior cranial fossa. The chordoma cases were distributed as follows according to extent of removal: total removal, 68 (66.02%);subtotal removal, 25 (24.27%);and partial removal, 10 (9.71%). The adenomas of the pituitary gland were removed totally in 6 cases, subtotally in 1 case and partially in 2 cases. The meningiomas were removed totally in 1 case, subtotally in 5 cases, and partially in 5 cases, with less than 50% of the tumor removed in 1 case. Other tumors (

关键词： Clivus Clival chordoma Endoscopic endonasal transclival approach Monitoring of cranial nerves Posterior cranial fossa Skull base anatomy Skull base surgery

Concerning spikes in emission and absorption in the microwave range

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Research in Astronomy and Astrophysics 2013年第1期13卷 115-128页

作者： Gennady P.chernov Robert A.Sych Guang-Li Huang Hai-Sheng Ji Yi-Hua Yan Cheng-Ming Tan Key Laboratory of Solar Activity National Astronomical ObservatoryChinese Academy of Sciences Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences (IZMIRAN) Institute of Solar-Terrestrial Physics Purple Mountain Observatory Chinese Academy of Sciences

In some events, weak fast solar bursts （near the level of the quiet Sun） were observed in the background of numerous spikes in emission and absorption. In such a case, the background contains the noise signals of the receiver. In events on 2005 September 16 and 2002 April 14, the solar origin of fast bursts was confirmed by simultaneous recording of the bursts at several remote observatories. The noisy background pixels in emission and absorption can be excluded by subtracting a higher level of continuum when constructing the spectra. The wavelet spectrum, noisy pro- files in different polarization channels and a spectrum with continuum level greater than zero demonstrates the noisy character of pixels with the lowest levels of emission and absorption. Thus, in each case, in order to judge the solar origin of all spikes, it is necessary to determine the level of continuum against the background of which the solar bursts are observed. Several models of microwave spikes are discussed. The electron cyclotron maser emission mechanism runs into serious problems with the in- terpretation of microwave millisecond spikes： the main obstacles are too high values of the magnetic field strength in the source （Pe 〈 uB）. The probable mechanism is the interaction of plasma Langmuir waves with ion-sound waves （l ＋ s → t） in a source related to shock fronts in the reconnection region.

关键词： solar flare -- radio emission -- spike-bursts