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Selection of suitable internal controls for gene expression normalization in rats with spinal cord injury

Neural Regeneration Research 2022年第6期17卷 1387-1392页

作者： Wei Liu Jie Yu Yi-Fan Wang qian-qian shan Ya-Xian Wang Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education Co-innovation Center of NeuroregenerationNational Medical Products Administration(NMPA)Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Department of Nursing The Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Clinical Medicine Medical School of Nantong UniversityNantongJiangsu ProvinceChina Department of Radiotherapy and Oncology The Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

There is a lack of systematic research on the expression of internal control genes used for gene expression normalization in real-time reverse transcription polymerase chain reaction in spinal cord injury *** this study,we used rat models of spinal cord hemisection to analyze the expression stability of 13 commonly applied reference genes:Actb,Ankrd27,CypA,Gapdh,Hprt1,Mrpl10,Pgk1,Rictor,Rn18s,Tbp,Ubc,Ubxn11,and *** results show that the expression of Ankrd27,Ubc,and Tbp were stable after spinal cord injury,while Actb was the most unstable internal control ***27,Ubc,Tbp,and Actb were consequently used to investigate the effects of internal control genes with differing stabilities on the normalization of target gene *** gene expression levels and changes over time were similar when Ankrd27,Ubc,and Tbp were used as internal controls but different when Actb was used as an internal *** recommend that Ankrd27,Ubc,and Tbp are used as internal control genes for real-time reverse transcription polymerase chain reaction in spinal cord injury *** study was approved by the Administration Committee of Experimental Animals,Jiangsu Province,China(approval No.20180304-008)on March 4,2018.

关键词： geNorm analysis reference genes internal control genes normalization NormFinder analysis reverse transcription-quantitative polymerase chain reaction spinal cord injury stability of gene expression

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Model fitting of the kinematics of ten superluminal components in blazar 3C 279

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Research in Astronomy and Astrophysics 2013年第7期13卷 783-802页

作者： shan-Jie qian National Astronomical Observatories Chinese Academy of Sciences

The kinematics of ten superluminal components （C11-C16, C18, C20, C21 and C24） of blazar 3C 279 are studied from VLBI observations. It is shown that their initial trajectory, distance from the core and apparent speed can be well fitted by the precession model proposed by qian. Combined with the results of the model fit for the six superluminal components （C3, C4, C7a, C8, C9 and C10） already pub-lished, the kinematics of sixteen superluminal components can now be consistently interpreted in the precession scenario with their ejectiontimes spanning more than 25 yr （or more than one precession period）. The results from model fitting show the possible existence of a common precessing trajectory for these knots within a pro- jected core distance of ～0.2-0.4 mas. In the framework of the jet-precession scenario, we can, for the first time, identify three classes of trajectories which are character-ized by their collimation parameters. These different trajectories could be related to the helical structure of magnetic fields in the jet. Through fitting the model, the bulk Lorentz factor, Doppler factor and viewing angle of these knots are derived. It is found that there is no evidence for any correlation between the bulk Lorentz factor of the components and their precession phase （or ejection time）. In a companion paper, the kinematics of another seven components （C5a, C6, C7, C17, C19, C22 and C23） have been derived from model fitting, and a binary black-hole/jet scenario was envisaged. The precession model proposed by qian would be useful for understanding the kine- matics of superluminal components in blazar 3C 279 derived from VLBI observations, by disentangling different mechanisms and ingredients. More generally, it might also be helpful for studying the mechanism of jet swing （wobbling） in other blazars.

关键词： radio continuum - galaxies jets - galaxies kinematics - galaxies individual (blazar 3C 279)

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Model simulation for periodic double-peaked outbursts in blazar OJ 287: binary black hole plus lighthouse effect

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Research in Astronomy and Astrophysics 2015年第5期15卷 687-712页

作者： shan-Jie qian National Astronomical Observatories Chinese Academy of Sciences

The mechanism of formation for double-peaked optical outbursts observed in blazar OJ 287 is studied. It is shown that they could be explained in terms of a light- house effect for superluminal optical knots ejected from the center of the galaxy that move along helical magnetic fields. It is assumed that the orbital motion of the secondary black hole in the supermassive binary black hole system induces the 12-year quasi-periodicity in major optical outbursts by the interaction with the disk around the primary black hole. This interaction between the secondary black hole and the disk of the primary black hole （e.g. tidal effects or magnetic coupling） excites or injects plas- mons （or relativistic plasmas plus magnetic field） into the jet which form superluminal knots. These knots are assumed to move along helical magnetic field lines to produce the optical double-peaked outbursts by the lighthouse effect. The four double-peaked outbursts observed in 1972, 1983, 1995 and 2005 are simulated using this model. It is shown that such lighthouse models are quite plausible and feasible for fitting the double-flaring behavior of the outbursts. The main requirement may be that in OJ 287 there exists a rather long （～40-60 pc） highly collimated zone, where the lighthouse effect occurs.

关键词： optical continuum -- galaxies jets -- galaxies kinematics -- galaxies variability -- galaxies individual (blazar OJ 287)

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Non-ballistic motion and precessing helical trajectory in quasar NRAO 150

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Research in Astronomy and Astrophysics 2016年第1期16卷 175-189页

作者： shan-Jie qian National Astronomical Observatories Chinese Academy of Sciences

NRAO 150 is a very special radio quasar in which prominent non-ballistic superluminal motion has been observed in its inner-jet region. We apply model-fittings to the kinematics of the superluminal knots（trajectory, distance from the core and apparent velocity） in terms of a helical precessing jet-nozzle *** cases are considered in which the angle between the jet axis and the line of sight is assumed to be 6？,3？, 1？, 0.6？ and 0.12？, respectively. It is shown that the superluminal components have intrinsic acceleration in the innermost regions（≤0.2 mas from the core）. The phenomenon of precessing nozzle/trajectory can be understood on the basis of relativistic magnetohydrodynamic theories for relativistic jets.

关键词： radio continuum: galaxies -- galaxies: jets -- galaxies: kinematics -- galaxies: individual(quasar NRAO 150)

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A possible precession period for superluminal ejection in QSO 3C 279

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Research in Astronomy and Astrophysics 2011年第1期11卷 43-62页

作者： shan-Jie qian National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

The search for periodic features in fiux variability and superluminal ejection in blazars has been an important subject, which is helpful for providing significant clues to the understanding of the structure and kinematics of relativistic jets （physical processes of acceleration and collimation） and their association with central energy engines （black hole/accretion disk systems）. The wobbling of the ejection position angle of VLBI knots in superluminal sources has been interpreted in terms of the precession of the jet ejection nozzle as one of the alternative interpretations. We study the change with time of the initial position angle of superluminal knots in QSO 3C 279, using VLBI-data collected from the literature spanning more than ～30 yr and propose a jet-nozzle precession model which has very small viewing angles （less than 2°） to fit the long-term trends in both variations in the inner-jet position angle （Chatterjee et al.） and the ejection position angle of the VLBI components. It is shown that an ejection-nozzle precession period of ～25 yr could be appropriate to fit the long-term trend in the variation of the ejection position angle. However, the short-term swings and fluctuations in the ejection position angle cause some uncertainties. We also fit a model to the trajectory of component C4, correcting its non-ballistic motion near the core.

关键词： radio continuum -- quasars -- jets -- kinematics -- individual: 3C 279

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Model-fitting of the kinematics of superluminal components in blazar 3C 279

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Research in Astronomy and Astrophysics 2012年第1期12卷 46-62页

作者： shan-Jie qian National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

A precessing jet-nozzle model with a precession period of about 25 yr has been proposed by qian to interpret the change with time of the ejection position an- gle of the superluminal components observed using very long baseline interferometry （VLBI） in the blazar 3C 279. We discuss the kinematic properties of six superluminal knots （C3, C4, C7a, C8, C9 and C10） and show that their trajectory, core-distance and apparent speed, derived from VLBI observations, can be consistently well fitted by the model. Their intrinsic Lorentz factors of bulk superluminal motion are thus derived, and the evidence shows no relation between Lorentz factor and the precession phase. Interestingly, for the C7a and C8 knots, the fitted core-distance ranges from ,,～0.1 mas to ～0.4 mas and for knots C9 and C10 from ～0.2mas to ～1.0-1.5 mas. For knot C4, its trajectory and apparent velocity are well fitted in the core-distance range from H1 mas to ～5 mas, taking into account a curvature of the trajectory at core-distance larger than ,,～3 mas. The consistent fitting of the kinematics of these components clearly demonstrates that the amplitude function and collimation param- eter adopted in the precession model are appropriate and applicable for both the in- ner and outer parts of the jet in 3C 279, but in some cases the jet curvature in the outer parts （or deviation from the model trajectory） needs to be seriously taken into consideration. With the exception of C4, the ejection position angles derived from the precession model are consistent with the values measured by VLBI observations （within about 3° - 6°）. Undoubtedly, the consistent interpretation of the kinematics in terms of the precession model for these superluminal components, with their ejection time spanning -～24 yr, significantly expands its applicability and implies that regular patterns of trajectories （or rotating channels） could exist in some periods.

关键词： radio continuum -- galaxies: jets -- galaxies: kinematics -- galaxies:individual (blazar 3C 279)

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引用

Chinese Journal of Astronomy and Astrophysics 2008年第2期8卷 219-229页

作者： shan-Jie qian National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

Correlated radio-optical variations on intraday timescales have been observed （e.g. in BLO 0716＋714） and such radio intraday variability is suggested to have an intrinsic origin. Recently, multi-wavelength observations, simultaneous at radio, mm-submm, optical and hard X-rays, of 0716＋714, show that during a period of intraday/interday variations at radio and mm wavelengths, the apparent brightness temperature of the source exceeded the Compton-limit （-10^12 K） by 2-4 orders of magnitude, but no Compton catastrophe （or no high luminosity of inverse-Compton radiation） was detected. It is also found that the intraday/interday variations at mm-submm wavelengths are consistent with the evolutionary behavior of a standard synchrotron source and for the intraday/interday variations at centimeter wavelengths opacity effects can play a significant role, which is consistent with the interpretation suggested previously by qian et al. Thus the apparent high brightness temperatures may probably be explained in terms of Doppler boosting effects due to bulk relativistic motion of the source. We will argue a scenario to simulate the correlations between the radio and optical variations on intraday timescales observed in BLO 0716＋714 in terms of a relativistic shock propagating through a jet with a dual structure.

关键词： optical and radio continuum: galaxies -- galaxies: intraday variability -- quasars: individual: BLO 0716+71

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Three-dimensional coordinates test method with uncertain projectile proximity explosion position based on dynamic seven photoelectric detection screen

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Defence Technology（防务技术） 2022年第9期18卷 1643-1652页

作者： Han-shan Li Xiao-qian Zhang School of Electronic and Information Engineering Xi'an Technological UniversityXi'an710021China

To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is *** to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters.

关键词： Dynamic multi-screen array plane Flash photoelectric detection target Projectile signal processing Particle swarm Proximity explosion fuze Three-dimensional coordinate

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Flight parameter calculation method of multi-projectiles using temporal and spatial information constraint

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Defence Technology（防务技术） 2023年第1期19卷 63-75页

作者： Han-shan Li Xiao-qian Zhang School of Electronic and Information Engineering Xi'an Technological UniversityXi'an710021China

The dynamic parameters of multiple projectiles that are fired using multi-barrel weapons in highfrequency continuous firing modes are important indicators to measure the performance of these *** characteristics of multiple projectiles are high randomness and large numbers launched in a short period of time,making it very difficult to obtain the real dispersion parameters of the projectiles due to the occlusion or coincidence of multiple *** six intersecting-screen testing system,in this paper,we propose an association recognition and matching algorithm of multiple projectiles using a temporal and spatial information constraint *** extract the output signal from each detection screen and then use the wavelet transform to process the output *** present a method to identify and extract the time values on which the projectiles pass through the detection screens using the wavelet transform modulus maximum *** then use the correlation of the output signals of three parallel detection screens to establish a correlation coefficient recognition constraint function for the multiple *** on the premise of linear projectile motion,we establish a temporal and spatial constraint matching model using the projectile’s position coordinates in each detection screen and the projectile’s time constraints within the multiple intersecting-screen *** then determine the time values of the multiple projectiles in each detection screen using an iterative search cycle registration,and finally obtain the flight parameters for the multiple projectiles in the presence of *** proposed method and algorithm were verified experimentally and can solve the problem of uncertainty in projectiles flight parameter under different multiple projectile firing states.

关键词： Six detection screen array Multi-projectile Recognition and matching Temporal and spatial information constraint Wavelet transform

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Multi-area detection sensitivity calculation model and detection blind areas influence analysis of photoelectric detection target

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Defence Technology（防务技术） 2022年第4期18卷 547-556页

作者： Han-shan Li Xiao-qian Zhang Hui Guan School of Electronic and Information Engineering Xi’an Technological UniversityXi’an710021China

Multi-element array photoelectric detector is the core devices to form a photoelectric detection target with a large field of *** photoelectric detection target brings about the problem of uneven detection sensitivity distribution in the detection *** improve the uneven detection sensitivity of this photoelectric detection target,this paper analyzes the distribution law of the uneven detection sensitivity of the photoelectric detection target using the multi-element array photoelectric detector,dissects the main factors affecting the detection sensitivity according to the photoelectric detection principle,establishes the calculation model of detection sensitivity of the photoelectric detection target in the different detection areas and proposes a method to improve the detection sensitivity by compensating the gain of each unit photoelectric *** analysis of simulation and experimental results show that the proposed method of photoelectric detection target can effectively improve the output signal amplitude of the projectile under the certain detection distance,in particular,the output signal amplitude of the projectile is significantly increased when the projectile passes through the detection blind *** experimental results are consistent with the simulation results,which verify the effectiveness of the proposed improvement method.

关键词： Projectile Photoelectric detection target Multi-element array photoelectric detector Detection sensitivity Detection screen

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