Summary: This study was designed to determine the effects of the recombinant adeno-associated virus vector containing sense CD151 gene (rAAV-CD151) and antisense CD151 gene (rAAV-antiCD151) on the migration of Tca8113...Summary: This study was designed to determine the effects of the recombinant adeno-associated virus vector containing sense CD151 gene (rAAV-CD151) and antisense CD151 gene (rAAV-antiCD151) on the migration of Tca8113 cell. Functional fragment of CD151 gene was amplified by RT-PCR, and inserted into the vector pAAV in the sense direction and antisense direction, respectively. The rAAV-CD151 and rAAV-antiCD151 were produced and the titers were determined by dot blot. The CD151, at protein level, was detected by Western blot. The Transwell chamber was used to detect the effects of the rAAV-CD151 and rAAV-antiCD151 on the tumor cell migration. The titers of the rAAV-CD151 and rAAV-antiCD151 were 2×10~11 pfu/ml and 1.0×10~11 pfu/ml, respectively. The expression of CD151 was increased by 108 % in the cells transfected with rAAV-CD151 and decreased by 79 % in the cells transfected with rAAV-antiCD151, as compared with non-transfected cells, respectively. The number of the migrating cells was significantly increased in the cells transfected with rAAV-CD151 (93.56±11.59) and decreased in the cells transfected with rAAV-antiCD151 (24.00±4.36) as compared with non-transfected and rAAV-GFP transfected cells (53.00±6.56 and 46.00±7.00, P<0.05). It is an important molecular mechanism of the tumor metastasis that the overexpression of CD151 promotes the migration of the tumor cells. The rAAV-antiCD151 is a novel tool, which can reduce the expression of CD151 and inhibit the migration of the tumor cells, and brings us a new approach of anti-sene gene therapy targeted at CD151 in human carcinoma.展开更多
Knowledge of the statistical characteristics of inversions and their effects on aerosols under different large-scale synoptic circulations is important for studying and modeling the diffusion of pollutants in the boun...Knowledge of the statistical characteristics of inversions and their effects on aerosols under different large-scale synoptic circulations is important for studying and modeling the diffusion of pollutants in the boundary layer. Based on results gen- erated using the self-organizing map （SOM） weather classification method, this study compares the statistical characteristics of surface-based inversions （SBIs） and elevated inversions （EIs）, and quantitatively evaluates the effect of SBIs on aerosol condensation nuclei （CN） concentrations and the relationship between temperature gradients and aerosols for six prevailing synoptic patterns over the the Southern Great Plains （SGP） site during 2001-10. Large-scale synoptic patterns strongly influ- ence the statistical characteristics of inversions and the accumulation of aerosols in the low-level atmosphere. The activity, frequency, intensity, and vertical distribution of inversions are significantly different among these synoptic patterns. The verti- cal distribution of inversions varies diurnally and is significantly different among the different synoptic patterns. Anticyclonic patterns affect the accumulation of aerosols near the ground more strongly than cyclonic patterns. Mean aerosol CN con- centrations increase during SBIs compared to no inversion cases by 16.1%, 22.6%, 24.5%, 58.7%, 29.8% and 23.7% for the six synoptic patterns. This study confirms that there is a positive correlation between temperature gradients and aerosol CN concentrations near the ground at night under similar large-scale synoptic patterns. The relationship is different for different synoptic patterns and can be described by linear functions. These findings suggest that large-scale synoptic patterns change the static stability of the atmosphere and inversions in the lower atmosphere, thereby influencing the diffusion of aerosols near the ground.展开更多
The electrodes for hardfacing medium carbon steel with six additions of rare earth oxide were developed in this work. By means of optical microscopy and scanning electron microscopy, the microstructure, inclusion and ...The electrodes for hardfacing medium carbon steel with six additions of rare earth oxide were developed in this work. By means of optical microscopy and scanning electron microscopy, the microstructure, inclusion and the fractograph of the hardfacing metal were observed. Then, the effects of rare earth oxide on microstructure and inclusions in hardfacing metal were analyzed. The effectiveness of rare earth oxide as heterogeneous nuclei of δ-Fe was calculated with the misfit theory. The results showed that, the microstructure of hardfacing metal was composed of ferrite and small amount of pearlite. The microstructure was refined at first and then coarsened with the increase of rare earth oxide addition. The fractograph was changed from brittle to equiaxed dimples, then became quasi-cleavage and cleavage gradually. The calculated results showed that, the ferrite grain size could be refined because that LaAlO3 as heterogeneous nuclei of δ-Fe was moderately effective, and the ferrite grain size was coarsened because the misfits between Ce2O3 and δ-Fe, Ce2O2S and δ-Fe were increased with futher increase of rare earth oxide addition.展开更多
The tip-leakage vortex(TLV)cavitation is a challenging issue for a variety of axial hydraulic turbines and pumps from both technical and scientific viewpoints.The flow characteristics of the TLV cavitation were widely...The tip-leakage vortex(TLV)cavitation is a challenging issue for a variety of axial hydraulic turbines and pumps from both technical and scientific viewpoints.The flow characteristics of the TLV cavitation were widely studied in the past decades,but the knowledge about the tip-leakage cavitating flow is still limited.The present paper reviews the progresses in the researches of the TLV cavitation,including the numerical methods for the TLV cavitation,the flow characteristics of the TLV,the influences of the TLV cavitation on the local flow field and the control strategies of the TLV cavitation.It is indicated that the non-condensable gas may play an important role in the development of the TLV cavitation,and this fact should be considered during a careful simulation of the TLV cavitation.It is also suggested that the development of the TLV cavitation will significantly influence the distributions of the vorticity and the turbulence kinetic energy.Due to the complexity of the TLV cavitation,it is still an open question how to suppress the TLV cavitation in a simple but effective way.Finally,based on these understandings,some advanced topics for the future work are suggested to further promote the study of the TLV cavitation,for a deeper knowledge about the TLV cavitation.展开更多
Peripheral and central sensitizations are phenomena that occur during migraine. The role of gabapentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was ...Peripheral and central sensitizations are phenomena that occur during migraine. The role of gabapentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was established by electrical stimulation of the trigeminal ganglion, and the animals were given intragastric gabapentin. Changes in amino acid content in the cerebrospinal fluid and protein kinase C membrane translocation in the spinal trigeminal nucleus were examined to clarify the mechanisms underlying the efficacy of gabapentin in the treatment of central sensiti- zation during migraine. Electrophysiology, liquid chromatography-mass spectrometry and western blot analysis results revealed that gabapentin reduces neuronal excitability in the spinal nucleus in the trigeminal nerve, decreases excitatory amino acid content and inhibits the activation of protein kinase C. This provides evidence that excitatory amino acids and protein kinase C are involved in the formation and maintenance of central sensitization during migraine. Gabapentin inhibits mi- graine by reducing excitatory amino acid content in the cerebrospinal fluid and inhibiting protein kinase C activation.展开更多
To construct eukaryotic expression vector expressing full length anti-sense pituitary tumor transforming gene (PTTG) mRNA and observe its blocking effect on the potential invasion of human ovarian carcinoma cell line ...To construct eukaryotic expression vector expressing full length anti-sense pituitary tumor transforming gene (PTTG) mRNA and observe its blocking effect on the potential invasion of human ovarian carcinoma cell line SK-OV-3. PCR primers containing designed enzyme cut sites were used for cloning full-length PTTG gene fragment, and the resulting PCR product was inserted into the eukaryotic vector pcDNA3.1 in the antisense direction. The recombinant vector was then transfected into SK-OV-3 by Lipofectamine. The positive cell clone was screened by G418, PTTG and bFGF at protein level expression were detected by Western blot. The biological behavior change of transfection positive cells was observed by colony formation in soft agar assay. Our results showed that SK-OV-3 clones stably expressing full-length recombinant pcDNA3.1-PTTGas were obtained. The expressions of PTTG and bFGF protein in transfected cells were decreased by 61.5 % and 52.3%, respectively as compared with non-transfected ones. The number of colony formation was reduced significantly in transfected cells as compared with empty vector transfected and non-transfected cells. It is concluded that the recombinant vector pcDNA3.1-PTTGas is a novel tool and provides an alternative anti-sense gene therapy targeted at PTTG in human carcinoma.展开更多
Black carbon （BC） concentration and meteorological data are measured discontinuously from May 2009 to March 2011,at the Qilian Shan Station of Glaciology and Ecologic Environment （hereafter ＂QSSGEE＂）,located nea...Black carbon （BC） concentration and meteorological data are measured discontinuously from May 2009 to March 2011,at the Qilian Shan Station of Glaciology and Ecologic Environment （hereafter ＂QSSGEE＂）,located near the terminal of the Laohugou No.12 Glacier in northwestern Qilian Shan,China.We measured the daily,monthly and seasonal variations of BC concentration in the atmosphere and discussed the possible emission sources.Black carbon background concentration in this region varied in the range of 18–72 ng/m 3 with the highest in summer and the lowest in autumn.The relations between BC concentration and surface wind direction indicated that BC concentration was higher when northwest wind prevails while lower when southeast wind prevails.Air masses backward trajectories showed the potential emission sources in the northwest.Significant positive correlations between daily mean BC concentration and relative humidity indicated that BC might be one of important cloud condensation nuclei.This hypothesis needs to be confirmed further through cloud microphysical features in this region.展开更多
The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei...The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei.The development of rare isotope accelerators offers opportunities for such studies.To date,many relevant measurements have been performed at accelerators using the projectile fragmentation technique,while the measurements at accelerators using isotope separator on-line(ISOL)systems are still quite scarce.In this work,we present the first proof-of-principle experiment with a post-accelerated ISOL beam at the Beijing Radioactive Ion Beam Facility(BRIF)by measuring the angular distribution of elastic scattering for the stable nucleus^(23)Na from the doubly magic nucleus^(40)Ca at energies above the Coulomb barrier.The angular distribution measured by a silicon strip detector array in a scattering chamber using the ISOL beam at BRIF is in good agreement with that measured by the high-precision Q3 D magnetic spectrograph using the nonISOL beam at nearly the same energy.This work provides useful background for making BRIF a powerful tool for the investigation of the reaction dynamics of exotic nuclei.展开更多
Along with the development of the radioactive nuclear beam facility, the study of the structure of unstable nuclei has progressed rapidly over the last few decades. Due to the weakly binding property, the structure in...Along with the development of the radioactive nuclear beam facility, the study of the structure of unstable nuclei has progressed rapidly over the last few decades. Due to the weakly binding property, the structure information of the unstable nuclei comes primarily from the scattering or reaction experiments. Therefore it would be very important to understand clearly the reaction mechanism involved in the experiment. We outlined here the major reaction mechanisms which are adequate to the study of unstable nuclei, with the focus on the new phenomena and methods in comparison with those with traditional stable nucleus beam. Especially emphasized are the breakup and knockout reactions, developed as accurate tools for spectroscopy investigation into the nuclear structure with low intensity secondary beam. Couplings of the breakup channel to the elastic scattering and the fusion and transfer reactions are also reviewed.展开更多
文摘Summary: This study was designed to determine the effects of the recombinant adeno-associated virus vector containing sense CD151 gene (rAAV-CD151) and antisense CD151 gene (rAAV-antiCD151) on the migration of Tca8113 cell. Functional fragment of CD151 gene was amplified by RT-PCR, and inserted into the vector pAAV in the sense direction and antisense direction, respectively. The rAAV-CD151 and rAAV-antiCD151 were produced and the titers were determined by dot blot. The CD151, at protein level, was detected by Western blot. The Transwell chamber was used to detect the effects of the rAAV-CD151 and rAAV-antiCD151 on the tumor cell migration. The titers of the rAAV-CD151 and rAAV-antiCD151 were 2×10~11 pfu/ml and 1.0×10~11 pfu/ml, respectively. The expression of CD151 was increased by 108 % in the cells transfected with rAAV-CD151 and decreased by 79 % in the cells transfected with rAAV-antiCD151, as compared with non-transfected cells, respectively. The number of the migrating cells was significantly increased in the cells transfected with rAAV-CD151 (93.56±11.59) and decreased in the cells transfected with rAAV-antiCD151 (24.00±4.36) as compared with non-transfected and rAAV-GFP transfected cells (53.00±6.56 and 46.00±7.00, P<0.05). It is an important molecular mechanism of the tumor metastasis that the overexpression of CD151 promotes the migration of the tumor cells. The rAAV-antiCD151 is a novel tool, which can reduce the expression of CD151 and inhibit the migration of the tumor cells, and brings us a new approach of anti-sene gene therapy targeted at CD151 in human carcinoma.
基金sponsored by the U.S. Department of Energy (DOE)supported by the Ministry of Science and Technology of China (Grant Nos. 2010CB950804 and 2013CB955801)+1 种基金the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDA05100300)the National Natural Science Foundation of China (Grant No. 41305011)
文摘Knowledge of the statistical characteristics of inversions and their effects on aerosols under different large-scale synoptic circulations is important for studying and modeling the diffusion of pollutants in the boundary layer. Based on results gen- erated using the self-organizing map （SOM） weather classification method, this study compares the statistical characteristics of surface-based inversions （SBIs） and elevated inversions （EIs）, and quantitatively evaluates the effect of SBIs on aerosol condensation nuclei （CN） concentrations and the relationship between temperature gradients and aerosols for six prevailing synoptic patterns over the the Southern Great Plains （SGP） site during 2001-10. Large-scale synoptic patterns strongly influ- ence the statistical characteristics of inversions and the accumulation of aerosols in the low-level atmosphere. The activity, frequency, intensity, and vertical distribution of inversions are significantly different among these synoptic patterns. The verti- cal distribution of inversions varies diurnally and is significantly different among the different synoptic patterns. Anticyclonic patterns affect the accumulation of aerosols near the ground more strongly than cyclonic patterns. Mean aerosol CN con- centrations increase during SBIs compared to no inversion cases by 16.1%, 22.6%, 24.5%, 58.7%, 29.8% and 23.7% for the six synoptic patterns. This study confirms that there is a positive correlation between temperature gradients and aerosol CN concentrations near the ground at night under similar large-scale synoptic patterns. The relationship is different for different synoptic patterns and can be described by linear functions. These findings suggest that large-scale synoptic patterns change the static stability of the atmosphere and inversions in the lower atmosphere, thereby influencing the diffusion of aerosols near the ground.
基金Project supported by One Hundred Excellent Talents of Hebei Province of China (SPRC021)Key Project of Science and Technology of Hebei Province (09215106D)
文摘The electrodes for hardfacing medium carbon steel with six additions of rare earth oxide were developed in this work. By means of optical microscopy and scanning electron microscopy, the microstructure, inclusion and the fractograph of the hardfacing metal were observed. Then, the effects of rare earth oxide on microstructure and inclusions in hardfacing metal were analyzed. The effectiveness of rare earth oxide as heterogeneous nuclei of δ-Fe was calculated with the misfit theory. The results showed that, the microstructure of hardfacing metal was composed of ferrite and small amount of pearlite. The microstructure was refined at first and then coarsened with the increase of rare earth oxide addition. The fractograph was changed from brittle to equiaxed dimples, then became quasi-cleavage and cleavage gradually. The calculated results showed that, the ferrite grain size could be refined because that LaAlO3 as heterogeneous nuclei of δ-Fe was moderately effective, and the ferrite grain size was coarsened because the misfits between Ce2O3 and δ-Fe, Ce2O2S and δ-Fe were increased with futher increase of rare earth oxide addition.
基金the National Natural Science Foundation of China(Grant Nos.51822903,1772239)the China Postdoctoral Science Foundation(Grant No.2020M682471).
文摘The tip-leakage vortex(TLV)cavitation is a challenging issue for a variety of axial hydraulic turbines and pumps from both technical and scientific viewpoints.The flow characteristics of the TLV cavitation were widely studied in the past decades,but the knowledge about the tip-leakage cavitating flow is still limited.The present paper reviews the progresses in the researches of the TLV cavitation,including the numerical methods for the TLV cavitation,the flow characteristics of the TLV,the influences of the TLV cavitation on the local flow field and the control strategies of the TLV cavitation.It is indicated that the non-condensable gas may play an important role in the development of the TLV cavitation,and this fact should be considered during a careful simulation of the TLV cavitation.It is also suggested that the development of the TLV cavitation will significantly influence the distributions of the vorticity and the turbulence kinetic energy.Due to the complexity of the TLV cavitation,it is still an open question how to suppress the TLV cavitation in a simple but effective way.Finally,based on these understandings,some advanced topics for the future work are suggested to further promote the study of the TLV cavitation,for a deeper knowledge about the TLV cavitation.
基金financially sponsored by the Natural Science Foundation of Shandong Province,No.ZR2012HQ014a grant from the Science and Technology Plan Program of Universities in Shandong Province,No.J10LF14
文摘Peripheral and central sensitizations are phenomena that occur during migraine. The role of gabapentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was established by electrical stimulation of the trigeminal ganglion, and the animals were given intragastric gabapentin. Changes in amino acid content in the cerebrospinal fluid and protein kinase C membrane translocation in the spinal trigeminal nucleus were examined to clarify the mechanisms underlying the efficacy of gabapentin in the treatment of central sensiti- zation during migraine. Electrophysiology, liquid chromatography-mass spectrometry and western blot analysis results revealed that gabapentin reduces neuronal excitability in the spinal nucleus in the trigeminal nerve, decreases excitatory amino acid content and inhibits the activation of protein kinase C. This provides evidence that excitatory amino acids and protein kinase C are involved in the formation and maintenance of central sensitization during migraine. Gabapentin inhibits mi- graine by reducing excitatory amino acid content in the cerebrospinal fluid and inhibiting protein kinase C activation.
文摘To construct eukaryotic expression vector expressing full length anti-sense pituitary tumor transforming gene (PTTG) mRNA and observe its blocking effect on the potential invasion of human ovarian carcinoma cell line SK-OV-3. PCR primers containing designed enzyme cut sites were used for cloning full-length PTTG gene fragment, and the resulting PCR product was inserted into the eukaryotic vector pcDNA3.1 in the antisense direction. The recombinant vector was then transfected into SK-OV-3 by Lipofectamine. The positive cell clone was screened by G418, PTTG and bFGF at protein level expression were detected by Western blot. The biological behavior change of transfection positive cells was observed by colony formation in soft agar assay. Our results showed that SK-OV-3 clones stably expressing full-length recombinant pcDNA3.1-PTTGas were obtained. The expressions of PTTG and bFGF protein in transfected cells were decreased by 61.5 % and 52.3%, respectively as compared with non-transfected ones. The number of colony formation was reduced significantly in transfected cells as compared with empty vector transfected and non-transfected cells. It is concluded that the recombinant vector pcDNA3.1-PTTGas is a novel tool and provides an alternative anti-sense gene therapy targeted at PTTG in human carcinoma.
基金supported by the Global Change Research Program of China (No. 2010CB951401)the "Talent Project" of Chinese Academy of Sciences,National Natural Science Foundation of China (No. 40901046)+1 种基金the State Key Laboratory of Cryospheric Sciences (No. SKLCS-ZZ-2008-01)the China Meteorological Administration (No. GYHY201106023)
文摘Black carbon （BC） concentration and meteorological data are measured discontinuously from May 2009 to March 2011,at the Qilian Shan Station of Glaciology and Ecologic Environment （hereafter ＂QSSGEE＂）,located near the terminal of the Laohugou No.12 Glacier in northwestern Qilian Shan,China.We measured the daily,monthly and seasonal variations of BC concentration in the atmosphere and discussed the possible emission sources.Black carbon background concentration in this region varied in the range of 18–72 ng/m 3 with the highest in summer and the lowest in autumn.The relations between BC concentration and surface wind direction indicated that BC concentration was higher when northwest wind prevails while lower when southeast wind prevails.Air masses backward trajectories showed the potential emission sources in the northwest.Significant positive correlations between daily mean BC concentration and relative humidity indicated that BC might be one of important cloud condensation nuclei.This hypothesis needs to be confirmed further through cloud microphysical features in this region.
基金supported by the National Natural Science Foundation of China(Nos.11490561,11635015,11961141003,11805280,11975316,12075045,12005304,U1867212,U1867214)the National Key Research and Development Project(Nos.2016YFA0400502,2018YFA0404404)+1 种基金the Continuous Basic Scientific Research Project(No.WDJC-2019-13)the Leading Innovation Project(Nos.LC192209000701,LC202309000201).
文摘The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei.The development of rare isotope accelerators offers opportunities for such studies.To date,many relevant measurements have been performed at accelerators using the projectile fragmentation technique,while the measurements at accelerators using isotope separator on-line(ISOL)systems are still quite scarce.In this work,we present the first proof-of-principle experiment with a post-accelerated ISOL beam at the Beijing Radioactive Ion Beam Facility(BRIF)by measuring the angular distribution of elastic scattering for the stable nucleus^(23)Na from the doubly magic nucleus^(40)Ca at energies above the Coulomb barrier.The angular distribution measured by a silicon strip detector array in a scattering chamber using the ISOL beam at BRIF is in good agreement with that measured by the high-precision Q3 D magnetic spectrograph using the nonISOL beam at nearly the same energy.This work provides useful background for making BRIF a powerful tool for the investigation of the reaction dynamics of exotic nuclei.
基金supported by the National Basic Research Program of China(Grant No. 2007CB815002)the National Natural Science Foundation ofChina (Grant Nos. 11035001, 10775003,10827505 and 10821140159)the Fundamental Research Funds for the Central Universities of China
文摘Along with the development of the radioactive nuclear beam facility, the study of the structure of unstable nuclei has progressed rapidly over the last few decades. Due to the weakly binding property, the structure information of the unstable nuclei comes primarily from the scattering or reaction experiments. Therefore it would be very important to understand clearly the reaction mechanism involved in the experiment. We outlined here the major reaction mechanisms which are adequate to the study of unstable nuclei, with the focus on the new phenomena and methods in comparison with those with traditional stable nucleus beam. Especially emphasized are the breakup and knockout reactions, developed as accurate tools for spectroscopy investigation into the nuclear structure with low intensity secondary beam. Couplings of the breakup channel to the elastic scattering and the fusion and transfer reactions are also reviewed.
