Understanding ozone(O_(3))formation regime is a prerequisite in formulating an effective O_(3)pollution control strategy.Photochemical indicator is a simple and direct method in identifying O_(3)formation regimes.Most...Understanding ozone(O_(3))formation regime is a prerequisite in formulating an effective O_(3)pollution control strategy.Photochemical indicator is a simple and direct method in identifying O_(3)formation regimes.Most used indicators are derived from observations,whereas the role of atmospheric oxidation is not in consideration,which is the core driver of O_(3)formation.Thus,it may impact accuracy in signaling O_(3)formation regimes.In this study,an advanced three-dimensional numerical modeling system was used to investigate the relationship between atmospheric oxidation and O_(3)formation regimes during a long-lasting O_(3)exceedance event in September 2017 over the Pearl River Delta(PRD)of China.We discovered a clear relationship between atmospheric oxidative capacity and O_(3)formation regime.Over eastern PRD,O_(3)formation was mainly in a NO x-limited regime when HO_(2)/OH ratio was higher than 11,while in a VOC-limited regime when the ratio was lower than 9.5.Over central and western PRD,an HO_(2)/OH ratio higher than 5 and lower than 2 was indicative of NO x-limited and VOC-limited regime,respectively.Physical contribution,including horizontal transport and vertical transport,may pose uncertainties on the indication of O_(3)formation regime by HO_(2)/OH ratio.In comparison with other commonly used photochemical indicators,HO_(2)/OH ratio had the best performance in differentiating O_(3)formation regimes.This study highlighted the necessities in using an atmospheric oxidative capacity-based indicator to infer O_(3)formation regime,and underscored the importance of characterizing behaviors of radicals to gain insight in atmospheric processes leading to O_(3)pollution over a photochemically active region.展开更多
Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly und...Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an analy- sis of an image sequence obtained by the X-Ray Telescope onboard the Hinode spacecraft, we found that quasi-periodic outflows are present in the boundary of an active region. The flows are observed to occur intermittently, often with a period of 5-10 min. The proj ected flow speed can reach more than 200 km s^-1, while its distribution peaks around 50 km s^-1. This sporadic high-speed outflow may play an important role in the mass loading process of the slow solar wind. Our results may imply that the outflow of the slow solar wind in the boundary of the active region is intermittent and quasiperiodic in nature.展开更多
We present a detailed investigation of the evolution of observed net vertical current using a time series of vector magnetograms of the active region （AR） NOAA 11158 obtained from the Helioseismic and Magnetic Image...We present a detailed investigation of the evolution of observed net vertical current using a time series of vector magnetograms of the active region （AR） NOAA 11158 obtained from the Helioseismic and Magnetic Imager. We also discuss the relation of net current to the observed eruptive events. The AR evolved from the βγ to βγδ3 configuration over a period of six days. The AR had two sub-regions of activity with opposite chirality： one dominated by sunspot rotation producing a strong CME, and the other showing large shear motions producing a strong flare. The net current in each polarity over the CME producing sub-region increased to a maximum and then decreased when the sunspots were separated. The time profile of net current in this sub-region followed the time profile of the rotation rate of the south-polarity sunspot in the same sub-region. The net current in the flaring sub-region showed a sudden increase at the time of the strong flare and remained unchanged until the end of the observation, while the sunspots maintained their close proximity. The systematic evo- lution of the observed net current is seen to follow the time evolution of total length of strongly sheared polarity inversion lines in both of the sub-regions. The observed photospheric net current could be explained as an inevitable product of the emergence of a twisted flux rope, from a higher pressure confinement below the photosphere into the lower pressure environment of the photosphere.展开更多
Radio observations of some active regions (ARs) obtained with the Nobeyama radioheliograph at λ=1.76 cm are used for estimating the magnetic field strength in the upper chromosphere, based on thermal bremsstrahlung. ...Radio observations of some active regions (ARs) obtained with the Nobeyama radioheliograph at λ=1.76 cm are used for estimating the magnetic field strength in the upper chromosphere, based on thermal bremsstrahlung. The results are compared with the magnetic field strength in the photosphere from observations with the Solar Magnetic Field Telescope (SMFT) at Huairou Solar Observing Station of Beijing Astronomical Observatory. The difference in the magnetic field strength between the two layers seems reasonable. The solar radio maps of active regions obtained with the Nobeyama radioheliograph, both in total intensity (I-map) and in circular polarizations (V-map), are compared with the optical magnetograms obtained with the SMFT. The comparison between the radio map in circular polarization and the longitudinal photospheric magnetogram of a plage region suggests that the radio map in circular polarization is a kind of magnetogram of the upper chromosphere. The comparison of the radio map in total intensity with the photo-spheric vector magnetogram of an AR shows that the radio map in total intensity gives indications of magnetic loops in the corona, thus we have a method of defining the coronal magnetic structure from the radio I-maps at λ=1.76 cm. Analysing the I-maps, we identified three components: (a) a compact bright source; (b) a narrow elongated structure connecting two main magnetic islands of opposite polarities (observed in both the optical and radio magnetograms); (c) a wide, diffuse, weak component that corresponds to a wide structure in the solar active region which shows in most cases an S or a reversed S contour, which is probably due to the differential rotation of the Sun. The last two components suggest coronal loops on different spatial scales above the neutral line of the longitudinal photospheric magnetic field.展开更多
While we process observational data of the Flares 22, two rare phenomena of microwave ultra fast absorption (MUFA) are found for the first time. They occurred at 3 67 GHz and 4 00 GHz in the atmospheric layers above b...While we process observational data of the Flares 22, two rare phenomena of microwave ultra fast absorption (MUFA) are found for the first time. They occurred at 3 67 GHz and 4 00 GHz in the atmospheric layers above both active regions of NOAA/USAF 4808 and 5060 in the interval 05 h50 m17 s～05 h50 m25 s UT on May 19, 1987 and 07 h38 m50 s～07 h38 m58 s UT on June 29, 1988, respectively. These absorption phenomena were observed with Phoenix Ⅱ Micowave Spectrometer at three frequencies (1 42, 2 84 and 3 67 GHz) and (1 42, 2 84 and 4 00 GHz) at Yunnan observatory. Spike emissions appeared at both 2 84 GHz and 1 42 GHz. The notable observational characteristics of both absorption phenomena are given. A possible absorption mechanism of MUFA is discussed.展开更多
In this paper, solar active region (AR) 6891 is studied. The long term temporal (over a 8 day period) relationahip between vertical current evolution and flare are examined. We found that the day to day variation of t...In this paper, solar active region (AR) 6891 is studied. The long term temporal (over a 8 day period) relationahip between vertical current evolution and flare are examined. We found that the day to day variation of the flare number in the active region is more closly associated with the variation of net current intensity than that of total current intensity. The increase in negative current in the weak following polarity area is due to the reduction in negative current in the strong preceding area.展开更多
Airport active region is the airport's busiest areas, it is the groundwork of the study of the aircraft to the ground waiting to optimization problems and air traffic flow management. However, the concept of the a...Airport active region is the airport's busiest areas, it is the groundwork of the study of the aircraft to the ground waiting to optimization problems and air traffic flow management. However, the concept of the active region model is quite a lot of operations research, physics and other fields related to model and the interface between them is quite complex, difficult to use a uniform standard for effective modeling. In this paper, to research the model framework of airport active region based on the SMP2 standard, a good solution present to the above problems. And this paper discusses the SMP2 development methods and procedures. Then the research abstracts the airport active region into five sub-systems to design and integration the entire model and format a complete model framework.展开更多
In this paper, the theory and method of the fuzzy mathematics areused to probe the connection between the activity of the active region and characterizat ion of the sunspot groups, to build the subordinating function ...In this paper, the theory and method of the fuzzy mathematics areused to probe the connection between the activity of the active region and characterizat ion of the sunspot groups, to build the subordinating function according to the rela tionship between them and to evaluate comprehensively the activity of the active region on t he solar disk. The precise prediction of activity of the active regions has been obta ined by data reduction and analysis. The predicting accuracy is higher th an 95% . Forecast results indicate that the method of the fuzzy comprehensive evaluatio n is a good one for the solar activity prediction.展开更多
Using observations from the EUV Imaging Spectrometer （EIS） onboard Hinode, we exam the plasma dynamics around the edge of the active region 10977, possibly associated with the source of nascent slow/intermediate sol...Using observations from the EUV Imaging Spectrometer （EIS） onboard Hinode, we exam the plasma dynamics around the edge of the active region 10977, possibly associated with the source of nascent slow/intermediate solar wind. The correlation between the temporal profiles of the radiation intensity and Doppler shift for each emission line are analyzed. And three small regions with positive correlations for all the five emission lines are selected for a detailed analysis. In this work, Doppler blue （red） shift is defined as negative （positive）. We find that in Region 1, the radiation intensity （Doppler velocity） decreases by about 15% （about 3 km s-X）, and logarithmical differential emission measures （lg（DEMs）） reduces by about 0.06-0.10% at all temperatures, called ＂weak dimming＂, during a 30-min interval. In Region 2 and Region 3, however, the radiation intensity （Doppler velocity） increases by about 15% （about 3 km s-l）, and lg（DEMs） increases by about 0.06%~0.10% at all tempera- tures, called ＂weak brightening＂. Such weak dimming （weak brightening） could reflect a slow draining （replenishing） of plas- ma in the solar wind flux tubes, possibly due to a larger （smaller） outflow flux at high altitude than at low altitude. These sug- gest that the plasma supply could be intermittent with an alternation of draining and replenishing, for which the underlying physical process is yet unknown, at the source region of slow/intermediate solar wind.展开更多
Deep-seated catastrophic landslides,particularly rock or debris avalanches,travel extremely rapidly for long distances,causing severe damage over wide areas.This paper summarizes the geological and geomorphological fe...Deep-seated catastrophic landslides,particularly rock or debris avalanches,travel extremely rapidly for long distances,causing severe damage over wide areas.This paper summarizes the geological and geomorphological features of such events,which were induced by earthquakes and rainstorms in Asia,and then uses these features to predict future potential sites of failures.Most of the rock avalanches are preceded by gravitational slope deformation with topographic features,in which small scarps along future head of landslide are the most representative;the scarps can be identified in topographic images made by highresolution airborne LiDAR DEMs and may suggest the instability just before catastrophic failure.展开更多
The present study induced in vitro-cultured passage 4 bone marrow-derived mesenchymal stem cells to differentiate into neural-like cells with a mixture of alkaloid, polysaccharide, aglycone, glycoside, essential oils,...The present study induced in vitro-cultured passage 4 bone marrow-derived mesenchymal stem cells to differentiate into neural-like cells with a mixture of alkaloid, polysaccharide, aglycone, glycoside, essential oils, and effective components of Buyang Huanwu decoction （active principle region of decoction for invigorating yang for recuperation）. After 28 days, nestin and neuron-specific enolase were expressed in the cytoplasm. Reverse transcription-PCR and western blot analyses showed that nestin and neuron-specific enolase mRNA and protein expression was greater in the active principle region group compared with the original formula group. Results demonstrated that the active principle region of Buyang Huanwu decoction induced greater differentiation of rat bone marrow-derived mesenchymal stem cells into neural-like cells in vitro than the original Buyang Huanwu decoction formula.展开更多
There is chaos in the Gulf region. Saudi Arabia in conjunction with the United Arab Emirates, Bahrain, Egypt and other gulf countries,suddenly cut off diplomatic relations with Qatar expelling diplomats and citizens, ...There is chaos in the Gulf region. Saudi Arabia in conjunction with the United Arab Emirates, Bahrain, Egypt and other gulf countries,suddenly cut off diplomatic relations with Qatar expelling diplomats and citizens, exerting blockades on land, sea and aviation on June 5, 2017, with the excuse that Qatar supports terrorism- and damages regional security. Sandi Arabia and other gulf countries have issued an ultimatum on June 23, giving Qatar to 10 days to meet their 13 requirements. For a time, the Saudi-led group became the media hot word. The Gulf, once a rare peaceful land under the impact of the Arab Spring, now falls into chaos. The GCC in fact has split. This is another major diplomatic adventure that Saudi Arabia has taken in recent years.展开更多
The Funan-Huoqiu area is located in the border tectonic belt between the North China and South China active block regions. By means of seismological and geological surveys and synthetic analysis, evidences of tectonic...The Funan-Huoqiu area is located in the border tectonic belt between the North China and South China active block regions. By means of seismological and geological surveys and synthetic analysis, evidences of tectonic deformation in lower intensity have been found in the area since Late Pleistocene, where small earthquakes are distributed linearly along the main faults, conjugate shear joints are developed in the Upper Pleistocene nearby the faults. In the south of the studied region, fissures with different lengths, widths and directions occurred successively in Gushi, Huoqiu, Funan and other places of the area, in the 1970’s, and the direction of the fissures is approximately consistent with that of the Feizhong fault and Wanglaorenji fault. The authors hold that the clustering of small earthquakes, the conjugate shear joints developed in the Upper Pleistocene, the crumpled deformation of materials on fault plane, and the development of modern surface fissures in the area all reflect that the energy in the crust was slowly released, and that the weak deformation took place in corresponding faults. There was only one destructive earthquake taking place in the area (the Jiangkouji {M_S43/4} earthquake). Altogather, there has been weak activity in the area since the Late Quaternary, and it is mainly shown as a creep-slip.展开更多
Taking a typical active export-oriented region Zhejiang as an example, this paper tries to evaluate its Coordinated Development Degree （CDD） form 1997, focusing on the characteristics of its export-oriented econom〉...Taking a typical active export-oriented region Zhejiang as an example, this paper tries to evaluate its Coordinated Development Degree （CDD） form 1997, focusing on the characteristics of its export-oriented econom〉 and regional environment. The results show that Zhejiang ＇s CDD has kept increasing steadily after its slight drop in 1998. Finally, four measurements are proposed to promote sustainable development, including increasing and equalizing region＇s environmental investment, changing pollution-intensive export structure to avoid restricting the whole industrial structure, restricting simple spatial translocation of high-material consumption, high-energy consumption and high-pollution industries, etc.展开更多
A Chinese delegation of 24 persons headed by Mr. Luan Enjie, Vice Administrator of China National Space Administration (CNSA) attended the Second Asia-Pacific Conference on Multilateral Cooperation in Space Technology...A Chinese delegation of 24 persons headed by Mr. Luan Enjie, Vice Administrator of China National Space Administration (CNSA) attended the Second Asia-Pacific Conference on Multilateral Cooperation in Space Technology and Applications held at Islamabad, the Capital of Pakistan from April 22 to 26, 1995. Following the First AsiaPacific Workshop held in Beijing in December, 1992, and the First Asia-Pacific Conference on Multilateral Cooperation in展开更多
This study examines cloud radiative forcing （CRF） in the Asian monsoon region （0° 50°N, 60° 150°E） simulated by Intergovernmental Panel on Climate Change （IPCC） Fourth Assessment Report （AR4...This study examines cloud radiative forcing （CRF） in the Asian monsoon region （0° 50°N, 60° 150°E） simulated by Intergovernmental Panel on Climate Change （IPCC） Fourth Assessment Report （AR4） AMIP models. During boreal winter, no model realistically reproduces the larger long-wave cloud radiative forcing （LWCF） over the Tibet Plateau （TP） and only a couple of models reasonably capture the larger short-wave CRF （SWCF） to the east of the TP. During boreal summer, there are larger biases for central location and intensity of simulated CRF in active convective regions. The CRF biases are closely related to the rainfall biases in the models. Quantitative analysis further indicates that the correlation between simulated CRF and observations are not high, and that the biases and diversity in SWCF are larger than that in LWCF. The annual cycle of simulated CRF over East Asia （0°-50°N, 100°-145°E） is also examined. Though many models capture the basic annual cycle in tropics, strong LWCF and SWCF to the east of the TP beginning in early spring are underestimated by most models. As a whole, GFDL-CM2.1, MPI-ECHAM5, UKMO-HadGAM1, and MIROC3.2 （medres） perform well for CRF simulation in the Asian monsoon region, and the multi-model ensemble （MME） has improved results over the individual simulations. It is suggested that strengthening the physical parameterizations involved over the TP, and improving cumulus convection processes and model experiment design are crucial to CRF simulation in the Asian monsoon region.展开更多
BACKGROUND： An increasing number of studies have shown the effects of aging in basic cognitive processing and higher cognitive functions using functional magnetic resonance imaging （fMRI）. However, little is known ...BACKGROUND： An increasing number of studies have shown the effects of aging in basic cognitive processing and higher cognitive functions using functional magnetic resonance imaging （fMRI）. However, little is known about the aging effects in diverse cognitive abilities, such as spatial learning and reasoning. OBJECTIVE： To investigate the effect of aging on spatial cognitive performance and regional brain activation based on fMRI. DESIGN, TIME, AND SETTING： A block design for fMRI observation. This study was performed at the fMRI Laboratory, Brain Science Research Center, Korea Advanced Institute of Science and Technology from March 2006 to May 2009. PARTICIPANTS： Eight right-handed, male, college students in their 20s （mean age 21.5 years） and six right-handed, male, adults in their 40s （mean age 45.7 years）, who graduated from college, participated in the study. All subjects were healthy and had no prior history of psychiatric or neurological disorders. METHODS： A spatial task was presented while brain images were acquired using a 3T fMRI system （ISOL Technology, Korea）. The spatial tasks involved selecting a shape that corresponded to a given figure using four examples, as well as selecting a development figure of a diagram. MAIN OUTCOME MEASURES： The accuracy rate （number of correct answers/total number of items x 100%） of spatial tasks was calculated. Using the subtraction procedure, the activated areas in the brain during spatial tasks were color-coded by T-score. The double subtraction method was used to analyze the effect of aging between the two age groups （20s versus 40s）. RESULTS： The cerebellum, occipital lobe, parietal lobe, and frontal lobe were similarly activated in the two age groups. Increased brain activations, however, were observed in bilateral parietal and superior frontal lobes of the younger group. More activation was observed in bilateral middle frontal and right inferior frontal lobes in the older group. Compared with the older group, the younger men exhibited greater spatial performance （P = 0.012）. CONCLUSION： Reduced cognitive function correlated with decreased activation areas in the parietal lobe and altered activation in the frontal lobe.展开更多
Recent rapid progress in cyberinfrastructure in geosciences is providing seismologists an enormous boost for addressing multi-physical phenomena of regional seismic activities. The inherent nature of their multi-scale...Recent rapid progress in cyberinfrastructure in geosciences is providing seismologists an enormous boost for addressing multi-physical phenomena of regional seismic activities. The inherent nature of their multi-scale properties, from temporal to spatial spaces, makes it inevitably to be solved using large-scale computations and distributed parallel data processing schemes. Under such circumstance, using the advanced numerical algorithms and unstructured mesh generation technologies become the obstacles for modern seismologists. The main objective of this paper is to present a framework, which includes a parallel finite element simulation and distributed data infrastructure, to address the novel algorithms, state-of-the-art modeling and their implementation in regional seismicgenic systems. We also discuss and implement this framework to analyze the strong earthquake evolution processes in the Sichuan-Yunnan region. This study is the key to long-term seismic risk by estimates, providing a platform for predictive large-scale numerical simulation modeling of regional earthquake activities.展开更多
The multifunctional trans-activator Tat is an essential regulatory protein for HIV-1 replication and is characterized by high sequence diversity. Numerous experimental studies have examined Tat in HIV-1 subtype B, but...The multifunctional trans-activator Tat is an essential regulatory protein for HIV-1 replication and is characterized by high sequence diversity. Numerous experimental studies have examined Tat in HIV-1 subtype B, but research on subtype C Tat is lacking, despite the high prevalence of infections caused by subtype C worldwide. We hypothesized that amino acid differences contribute to functional differences among Tat proteins. In the present study, we found that subtype B NL4-3Tat and subtype C isolate HIV1084 i Tat exhibited differences in stability by overexpressing the fusion protein Tat-Flag. In addition, 1084 i Tat can activate LTR and NF-κB more efficiently than NL4-3 Tat. In analyses of the activities of the truncated forms of Tat, we found that the carboxylterminal region of Tat regulates its stability and transactivity. According to our results, we speculated that the differences in stability between B-Tat and C-Tat result in differences in transactivation ability.展开更多
基金sponsored by the National Natural Science Foundation of China(Nos.91644221,41575009)。
文摘Understanding ozone(O_(3))formation regime is a prerequisite in formulating an effective O_(3)pollution control strategy.Photochemical indicator is a simple and direct method in identifying O_(3)formation regimes.Most used indicators are derived from observations,whereas the role of atmospheric oxidation is not in consideration,which is the core driver of O_(3)formation.Thus,it may impact accuracy in signaling O_(3)formation regimes.In this study,an advanced three-dimensional numerical modeling system was used to investigate the relationship between atmospheric oxidation and O_(3)formation regimes during a long-lasting O_(3)exceedance event in September 2017 over the Pearl River Delta(PRD)of China.We discovered a clear relationship between atmospheric oxidative capacity and O_(3)formation regime.Over eastern PRD,O_(3)formation was mainly in a NO x-limited regime when HO_(2)/OH ratio was higher than 11,while in a VOC-limited regime when the ratio was lower than 9.5.Over central and western PRD,an HO_(2)/OH ratio higher than 5 and lower than 2 was indicative of NO x-limited and VOC-limited regime,respectively.Physical contribution,including horizontal transport and vertical transport,may pose uncertainties on the indication of O_(3)formation regime by HO_(2)/OH ratio.In comparison with other commonly used photochemical indicators,HO_(2)/OH ratio had the best performance in differentiating O_(3)formation regimes.This study highlighted the necessities in using an atmospheric oxidative capacity-based indicator to infer O_(3)formation regime,and underscored the importance of characterizing behaviors of radicals to gain insight in atmospheric processes leading to O_(3)pollution over a photochemically active region.
基金supported by the National Natural Science Foundation of China (Grant Nos.40874090 and 40931055)
文摘Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an analy- sis of an image sequence obtained by the X-Ray Telescope onboard the Hinode spacecraft, we found that quasi-periodic outflows are present in the boundary of an active region. The flows are observed to occur intermittently, often with a period of 5-10 min. The proj ected flow speed can reach more than 200 km s^-1, while its distribution peaks around 50 km s^-1. This sporadic high-speed outflow may play an important role in the mass loading process of the slow solar wind. Our results may imply that the outflow of the slow solar wind in the boundary of the active region is intermittent and quasiperiodic in nature.
基金supported by an INSPIRE grant under the AORC scheme of the Department of Science and Technology
文摘We present a detailed investigation of the evolution of observed net vertical current using a time series of vector magnetograms of the active region （AR） NOAA 11158 obtained from the Helioseismic and Magnetic Imager. We also discuss the relation of net current to the observed eruptive events. The AR evolved from the βγ to βγδ3 configuration over a period of six days. The AR had two sub-regions of activity with opposite chirality： one dominated by sunspot rotation producing a strong CME, and the other showing large shear motions producing a strong flare. The net current in each polarity over the CME producing sub-region increased to a maximum and then decreased when the sunspots were separated. The time profile of net current in this sub-region followed the time profile of the rotation rate of the south-polarity sunspot in the same sub-region. The net current in the flaring sub-region showed a sudden increase at the time of the strong flare and remained unchanged until the end of the observation, while the sunspots maintained their close proximity. The systematic evo- lution of the observed net current is seen to follow the time evolution of total length of strongly sheared polarity inversion lines in both of the sub-regions. The observed photospheric net current could be explained as an inevitable product of the emergence of a twisted flux rope, from a higher pressure confinement below the photosphere into the lower pressure environment of the photosphere.
文摘Radio observations of some active regions (ARs) obtained with the Nobeyama radioheliograph at λ=1.76 cm are used for estimating the magnetic field strength in the upper chromosphere, based on thermal bremsstrahlung. The results are compared with the magnetic field strength in the photosphere from observations with the Solar Magnetic Field Telescope (SMFT) at Huairou Solar Observing Station of Beijing Astronomical Observatory. The difference in the magnetic field strength between the two layers seems reasonable. The solar radio maps of active regions obtained with the Nobeyama radioheliograph, both in total intensity (I-map) and in circular polarizations (V-map), are compared with the optical magnetograms obtained with the SMFT. The comparison between the radio map in circular polarization and the longitudinal photospheric magnetogram of a plage region suggests that the radio map in circular polarization is a kind of magnetogram of the upper chromosphere. The comparison of the radio map in total intensity with the photo-spheric vector magnetogram of an AR shows that the radio map in total intensity gives indications of magnetic loops in the corona, thus we have a method of defining the coronal magnetic structure from the radio I-maps at λ=1.76 cm. Analysing the I-maps, we identified three components: (a) a compact bright source; (b) a narrow elongated structure connecting two main magnetic islands of opposite polarities (observed in both the optical and radio magnetograms); (c) a wide, diffuse, weak component that corresponds to a wide structure in the solar active region which shows in most cases an S or a reversed S contour, which is probably due to the differential rotation of the Sun. The last two components suggest coronal loops on different spatial scales above the neutral line of the longitudinal photospheric magnetic field.
文摘While we process observational data of the Flares 22, two rare phenomena of microwave ultra fast absorption (MUFA) are found for the first time. They occurred at 3 67 GHz and 4 00 GHz in the atmospheric layers above both active regions of NOAA/USAF 4808 and 5060 in the interval 05 h50 m17 s～05 h50 m25 s UT on May 19, 1987 and 07 h38 m50 s～07 h38 m58 s UT on June 29, 1988, respectively. These absorption phenomena were observed with Phoenix Ⅱ Micowave Spectrometer at three frequencies (1 42, 2 84 and 3 67 GHz) and (1 42, 2 84 and 4 00 GHz) at Yunnan observatory. Spike emissions appeared at both 2 84 GHz and 1 42 GHz. The notable observational characteristics of both absorption phenomena are given. A possible absorption mechanism of MUFA is discussed.
文摘In this paper, solar active region (AR) 6891 is studied. The long term temporal (over a 8 day period) relationahip between vertical current evolution and flare are examined. We found that the day to day variation of the flare number in the active region is more closly associated with the variation of net current intensity than that of total current intensity. The increase in negative current in the weak following polarity area is due to the reduction in negative current in the strong preceding area.
文摘Airport active region is the airport's busiest areas, it is the groundwork of the study of the aircraft to the ground waiting to optimization problems and air traffic flow management. However, the concept of the active region model is quite a lot of operations research, physics and other fields related to model and the interface between them is quite complex, difficult to use a uniform standard for effective modeling. In this paper, to research the model framework of airport active region based on the SMP2 standard, a good solution present to the above problems. And this paper discusses the SMP2 development methods and procedures. Then the research abstracts the airport active region into five sub-systems to design and integration the entire model and format a complete model framework.
基金This work was supported by the National Weighty Natural Science Foundation of China (Grant No. 49990451).
文摘In this paper, the theory and method of the fuzzy mathematics areused to probe the connection between the activity of the active region and characterizat ion of the sunspot groups, to build the subordinating function according to the rela tionship between them and to evaluate comprehensively the activity of the active region on t he solar disk. The precise prediction of activity of the active regions has been obta ined by data reduction and analysis. The predicting accuracy is higher th an 95% . Forecast results indicate that the method of the fuzzy comprehensive evaluatio n is a good one for the solar activity prediction.
基金supported by the National Natural Science Foundation of China(Grant Nos.41174148,41222032,40931055,41231069,41274172)supported by a foundation for the Author of National Excellent Doctoral Dissertation of China(FANEDD)(Grant No.201128)
文摘Using observations from the EUV Imaging Spectrometer （EIS） onboard Hinode, we exam the plasma dynamics around the edge of the active region 10977, possibly associated with the source of nascent slow/intermediate solar wind. The correlation between the temporal profiles of the radiation intensity and Doppler shift for each emission line are analyzed. And three small regions with positive correlations for all the five emission lines are selected for a detailed analysis. In this work, Doppler blue （red） shift is defined as negative （positive）. We find that in Region 1, the radiation intensity （Doppler velocity） decreases by about 15% （about 3 km s-X）, and logarithmical differential emission measures （lg（DEMs）） reduces by about 0.06-0.10% at all temperatures, called ＂weak dimming＂, during a 30-min interval. In Region 2 and Region 3, however, the radiation intensity （Doppler velocity） increases by about 15% （about 3 km s-l）, and lg（DEMs） increases by about 0.06%~0.10% at all tempera- tures, called ＂weak brightening＂. Such weak dimming （weak brightening） could reflect a slow draining （replenishing） of plas- ma in the solar wind flux tubes, possibly due to a larger （smaller） outflow flux at high altitude than at low altitude. These sug- gest that the plasma supply could be intermittent with an alternation of draining and replenishing, for which the underlying physical process is yet unknown, at the source region of slow/intermediate solar wind.
文摘Deep-seated catastrophic landslides,particularly rock or debris avalanches,travel extremely rapidly for long distances,causing severe damage over wide areas.This paper summarizes the geological and geomorphological features of such events,which were induced by earthquakes and rainstorms in Asia,and then uses these features to predict future potential sites of failures.Most of the rock avalanches are preceded by gravitational slope deformation with topographic features,in which small scarps along future head of landslide are the most representative;the scarps can be identified in topographic images made by highresolution airborne LiDAR DEMs and may suggest the instability just before catastrophic failure.
基金supported by the Natural Science Foundation of Anhui Province (Role of substance P in electroacupuncture for focal brain ischemia in rats), No. 050431003the National Natural Science Foundation of China (Target point and signal transduction pathway of Yangxin Tongmai active principle region for BMSCs), No. 81102595
文摘The present study induced in vitro-cultured passage 4 bone marrow-derived mesenchymal stem cells to differentiate into neural-like cells with a mixture of alkaloid, polysaccharide, aglycone, glycoside, essential oils, and effective components of Buyang Huanwu decoction （active principle region of decoction for invigorating yang for recuperation）. After 28 days, nestin and neuron-specific enolase were expressed in the cytoplasm. Reverse transcription-PCR and western blot analyses showed that nestin and neuron-specific enolase mRNA and protein expression was greater in the active principle region group compared with the original formula group. Results demonstrated that the active principle region of Buyang Huanwu decoction induced greater differentiation of rat bone marrow-derived mesenchymal stem cells into neural-like cells in vitro than the original Buyang Huanwu decoction formula.
文摘There is chaos in the Gulf region. Saudi Arabia in conjunction with the United Arab Emirates, Bahrain, Egypt and other gulf countries,suddenly cut off diplomatic relations with Qatar expelling diplomats and citizens, exerting blockades on land, sea and aviation on June 5, 2017, with the excuse that Qatar supports terrorism- and damages regional security. Sandi Arabia and other gulf countries have issued an ultimatum on June 23, giving Qatar to 10 days to meet their 13 requirements. For a time, the Saudi-led group became the media hot word. The Gulf, once a rare peaceful land under the impact of the Arab Spring, now falls into chaos. The GCC in fact has split. This is another major diplomatic adventure that Saudi Arabia has taken in recent years.
文摘The Funan-Huoqiu area is located in the border tectonic belt between the North China and South China active block regions. By means of seismological and geological surveys and synthetic analysis, evidences of tectonic deformation in lower intensity have been found in the area since Late Pleistocene, where small earthquakes are distributed linearly along the main faults, conjugate shear joints are developed in the Upper Pleistocene nearby the faults. In the south of the studied region, fissures with different lengths, widths and directions occurred successively in Gushi, Huoqiu, Funan and other places of the area, in the 1970’s, and the direction of the fissures is approximately consistent with that of the Feizhong fault and Wanglaorenji fault. The authors hold that the clustering of small earthquakes, the conjugate shear joints developed in the Upper Pleistocene, the crumpled deformation of materials on fault plane, and the development of modern surface fissures in the area all reflect that the energy in the crust was slowly released, and that the weak deformation took place in corresponding faults. There was only one destructive earthquake taking place in the area (the Jiangkouji {M_S43/4} earthquake). Altogather, there has been weak activity in the area since the Late Quaternary, and it is mainly shown as a creep-slip.
基金supported by the National Natural Science Foundation of China (Grant No. 40671062)the third stage of Knowledge In-novation Project of Institute of Geographic Sciences and Natural Resources Research, CAS.
文摘Taking a typical active export-oriented region Zhejiang as an example, this paper tries to evaluate its Coordinated Development Degree （CDD） form 1997, focusing on the characteristics of its export-oriented econom〉 and regional environment. The results show that Zhejiang ＇s CDD has kept increasing steadily after its slight drop in 1998. Finally, four measurements are proposed to promote sustainable development, including increasing and equalizing region＇s environmental investment, changing pollution-intensive export structure to avoid restricting the whole industrial structure, restricting simple spatial translocation of high-material consumption, high-energy consumption and high-pollution industries, etc.
文摘A Chinese delegation of 24 persons headed by Mr. Luan Enjie, Vice Administrator of China National Space Administration (CNSA) attended the Second Asia-Pacific Conference on Multilateral Cooperation in Space Technology and Applications held at Islamabad, the Capital of Pakistan from April 22 to 26, 1995. Following the First AsiaPacific Workshop held in Beijing in December, 1992, and the First Asia-Pacific Conference on Multilateral Cooperation in
基金supported by the CAS project under Grant No. KZCX2-YW-Q11-01the Major State Basic Research Development Program of China under Grant No. 2006CB403607the National Natural Science Foundation of China (Grant Nos.40523001, 40821092, 40875034)
文摘This study examines cloud radiative forcing （CRF） in the Asian monsoon region （0° 50°N, 60° 150°E） simulated by Intergovernmental Panel on Climate Change （IPCC） Fourth Assessment Report （AR4） AMIP models. During boreal winter, no model realistically reproduces the larger long-wave cloud radiative forcing （LWCF） over the Tibet Plateau （TP） and only a couple of models reasonably capture the larger short-wave CRF （SWCF） to the east of the TP. During boreal summer, there are larger biases for central location and intensity of simulated CRF in active convective regions. The CRF biases are closely related to the rainfall biases in the models. Quantitative analysis further indicates that the correlation between simulated CRF and observations are not high, and that the biases and diversity in SWCF are larger than that in LWCF. The annual cycle of simulated CRF over East Asia （0°-50°N, 100°-145°E） is also examined. Though many models capture the basic annual cycle in tropics, strong LWCF and SWCF to the east of the TP beginning in early spring are underestimated by most models. As a whole, GFDL-CM2.1, MPI-ECHAM5, UKMO-HadGAM1, and MIROC3.2 （medres） perform well for CRF simulation in the Asian monsoon region, and the multi-model ensemble （MME） has improved results over the individual simulations. It is suggested that strengthening the physical parameterizations involved over the TP, and improving cumulus convection processes and model experiment design are crucial to CRF simulation in the Asian monsoon region.
文摘BACKGROUND： An increasing number of studies have shown the effects of aging in basic cognitive processing and higher cognitive functions using functional magnetic resonance imaging （fMRI）. However, little is known about the aging effects in diverse cognitive abilities, such as spatial learning and reasoning. OBJECTIVE： To investigate the effect of aging on spatial cognitive performance and regional brain activation based on fMRI. DESIGN, TIME, AND SETTING： A block design for fMRI observation. This study was performed at the fMRI Laboratory, Brain Science Research Center, Korea Advanced Institute of Science and Technology from March 2006 to May 2009. PARTICIPANTS： Eight right-handed, male, college students in their 20s （mean age 21.5 years） and six right-handed, male, adults in their 40s （mean age 45.7 years）, who graduated from college, participated in the study. All subjects were healthy and had no prior history of psychiatric or neurological disorders. METHODS： A spatial task was presented while brain images were acquired using a 3T fMRI system （ISOL Technology, Korea）. The spatial tasks involved selecting a shape that corresponded to a given figure using four examples, as well as selecting a development figure of a diagram. MAIN OUTCOME MEASURES： The accuracy rate （number of correct answers/total number of items x 100%） of spatial tasks was calculated. Using the subtraction procedure, the activated areas in the brain during spatial tasks were color-coded by T-score. The double subtraction method was used to analyze the effect of aging between the two age groups （20s versus 40s）. RESULTS： The cerebellum, occipital lobe, parietal lobe, and frontal lobe were similarly activated in the two age groups. Increased brain activations, however, were observed in bilateral parietal and superior frontal lobes of the younger group. More activation was observed in bilateral middle frontal and right inferior frontal lobes in the older group. Compared with the older group, the younger men exhibited greater spatial performance （P = 0.012）. CONCLUSION： Reduced cognitive function correlated with decreased activation areas in the parietal lobe and altered activation in the frontal lobe.
基金supported by National Basic Research Program of China(2008cb425701)National Science Foundation of China under grants number(40774049)Knowledge Innovation Project of Chinese Academyof Sciences(kzcx2-yw-123)
文摘Recent rapid progress in cyberinfrastructure in geosciences is providing seismologists an enormous boost for addressing multi-physical phenomena of regional seismic activities. The inherent nature of their multi-scale properties, from temporal to spatial spaces, makes it inevitably to be solved using large-scale computations and distributed parallel data processing schemes. Under such circumstance, using the advanced numerical algorithms and unstructured mesh generation technologies become the obstacles for modern seismologists. The main objective of this paper is to present a framework, which includes a parallel finite element simulation and distributed data infrastructure, to address the novel algorithms, state-of-the-art modeling and their implementation in regional seismicgenic systems. We also discuss and implement this framework to analyze the strong earthquake evolution processes in the Sichuan-Yunnan region. This study is the key to long-term seismic risk by estimates, providing a platform for predictive large-scale numerical simulation modeling of regional earthquake activities.
基金supported by grants from the National Natural Science Foundation of China (No.81571987 and 81371820)the Ph.D. Candidate Research Innovation Fund of Nankai University (2015) (No.68150003)
文摘The multifunctional trans-activator Tat is an essential regulatory protein for HIV-1 replication and is characterized by high sequence diversity. Numerous experimental studies have examined Tat in HIV-1 subtype B, but research on subtype C Tat is lacking, despite the high prevalence of infections caused by subtype C worldwide. We hypothesized that amino acid differences contribute to functional differences among Tat proteins. In the present study, we found that subtype B NL4-3Tat and subtype C isolate HIV1084 i Tat exhibited differences in stability by overexpressing the fusion protein Tat-Flag. In addition, 1084 i Tat can activate LTR and NF-κB more efficiently than NL4-3 Tat. In analyses of the activities of the truncated forms of Tat, we found that the carboxylterminal region of Tat regulates its stability and transactivity. According to our results, we speculated that the differences in stability between B-Tat and C-Tat result in differences in transactivation ability.
