This paper investigates the dry climatology of Sahara and Northwest China deserts from the viewpoint of local meridional circulation with Xie and Arkin rainfall dada and NCAR/NCEP reanalysis data. Results show that th...This paper investigates the dry climatology of Sahara and Northwest China deserts from the viewpoint of local meridional circulation with Xie and Arkin rainfall dada and NCAR/NCEP reanalysis data. Results show that there are very dry centers with annual rainfall less than 50 mm over these two deserts while the rainy seasons are very different. In the south part of Sahara desert center and Northwest China desert, over 70% rainfall takes place in June, July and August (JJA). While in the north part of Sahara, rainfall mainly concentrates in December, January and February (DJF). The local biosphere-radiation mechanism proposed by Charney cannot explain the climatology of such very dry centers. Neither can the monsoon-desert mechanism proposed by Rodwell and Hoskins do for the strongest descent center is much more northward than the driest center over Sahara in JJA. From the viewpoint of local meridional circulation, the dryness climatology of Sahara and Northwest China deserts is investigated and compared. It is shown that in DJF, descent of local meridional circulation dominates the two deserts and very dry climate is unavoidable although the relative wet season is weak over the northern part of Sahara due to Mediterranean climate. While in JJA, there is ascent over the two deserts especially over Northwest China. Such ascent can explain the rainy season in south part of Sahara and Northwest China deserts. However, it is the local meridional circulation that takes strong and dry northerly from higher latitudes. The northerly either takes little moisture to the centers or prevents deep and strong convection over the centers. Such local meridional circulation leads to the dry climatology over the two deserts.展开更多
The 1979-2001 ERA-40 monthly mean meridional winds are used to calculate the mass streamfunctions in the monsoon region (60-140° E) and Nio zone (160° E-120° W),with which the climate characteristics an...The 1979-2001 ERA-40 monthly mean meridional winds are used to calculate the mass streamfunctions in the monsoon region (60-140° E) and Nio zone (160° E-120° W),with which the climate characteristics and intensity variation of the localized Hadley circulation (LHC) are analyzed over the two regions and the linkage of this LHC to Pacific SST is explored.Evidence suggests as follows.1) The climatological LHC is stronger in the monsoon than in the Nio zone,with its position in the former northward of the latter,especially in the summer half-year.The resulting difference is due mainly to the land-sea heterogeneous distribution and the existence of a cold pool in the equatorial eastern Pacific.2) The LHC experiences a distinct interannual variability in intensity and during 1979-2001 the LHC strength of the two regions changes broadly in an anti-phase manner.3) The LHC has its intensity associated closely with Pacific SST in such a way that its strength anomaly in the monsoon (Nio) band in January is correlated negatively (positively) with the SSTA over the all-Nio (1-4) zone (ANZ) in the equatorial middle and eastern Pacific but positively (negatively) correlated to SSTA in the C-shaped area that surrounds the ANZ.The pattern of July is in rough agreement with that of January,except for more feeble correlativity in July,especially over the monsoon region;4) The ENSO episode has different impacts on the LHC vigor in the two regions.With the occurrence of an El Nio,the LHC is weakened (strengthened) in the monsoon (Nio) region,and the reversal takes place during the La Nia year,with greater anomaly in the Nio area.展开更多
In an earlier study, the Atmospheric Models Intercomparison Program (AMIP) simulations of African climate using the nine-layer gridpoint atmospheric general circulation model were found to be closely related to the ob...In an earlier study, the Atmospheric Models Intercomparison Program (AMIP) simulations of African climate using the nine-layer gridpoint atmospheric general circulation model were found to be closely related to the observed European Centre for Medium Range Weather Forecast (ECMWF) temperature data at 500 and 850 hPa. This paper presents the analysis of the simulation of African climate using the Global Ocean-Atmosphere-Land System Model (IAP/LASG GOALS) and the nine-layer spectral general circulation model rhomboidally truncated at zonal wave number 15 (L9R15) developed at the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, Beijing. Both model simulations were not significantly different from the National Center for Environmental Prediction (NCEP) Reanalysis monthly mean data for 1980-1995 in the case of surface air temperature, sea level pressure and precipitation, with the GOALS reproducing the seasonal mean climate over Africa better. The implications of the encouraging results in developing a local area model for Nigeria have been discussed. The great role of topography in the developing of general circulation models for numerical modelling of weather and climate has been stressed.展开更多
BACKGROUND The poly(ADP-ribose)polymerase(PARP)inhibitor olaparib has displayed superior clinical effect in metastatic castration-resistant prostate cancer(mCRPC)patients with the homologous recombination repair(HRR)g...BACKGROUND The poly(ADP-ribose)polymerase(PARP)inhibitor olaparib has displayed superior clinical effect in metastatic castration-resistant prostate cancer(mCRPC)patients with the homologous recombination repair(HRR)genes mutations.However,when a patient’s tumor tissue volume is insufficient for genomic profiling of HRR gene mutations,circulating tumor DNA(ctDNA)may be useful in helping to determine and monitor the efficacy of olaparib,as well as in abiraterone-combination treatment,and for understanding any resistance mechanism related to such mutations.CASE SUMMARY A 61-year-old man who was diagnosed with metastatic prostate adenocarcinoma was initially hormone sensitivity,showing high Gleason score(5+5=10)and absolute positive rate(14/14 biopsied specimens).Following failure of several standard therapies,the patient progressed to mCRPC.Surprisingly,the patient showed good response to olaparib-abiraterone-prednisone combination treatment(an androgen-deprivation therapy,provided as the‘final choice’in China).Serum total prostate-specific antigen(TPSA)level reduced and symptoms remitted for 4 months.However,thereafter,serum TPSA levels began slowly increasing,indicating development of olaparib resistance.Subsequent comprehensive genomic profiling of ctDNA, screening 508 cancer-related genes by next-generation sequencing,identified 10 somatic variants as well as 3 copy number alterations. Two identified reversemissense mutations in partner and localizer of BRCA2 (PALB2) may have recovered the readingframe, restoring function of the primary germline PALB2 mutation and causing resistance to thePARP inhibitor olaparib.CONCLUSIONReverse mutations in PALB2, discovered via genomic profiling of ctDNA, may represent apotential resistance mechanism against olaparib in mCRPC.展开更多
Radial profiles of local gas and solid holdups and liquid interstitial velocity were measured in a largediameter three-phase fluidized bed, and a systematic study was carried out in comparing the present data with tho...Radial profiles of local gas and solid holdups and liquid interstitial velocity were measured in a largediameter three-phase fluidized bed, and a systematic study was carried out in comparing the present data with those obtained in small-diameter beds. Radial profiles of local gas holdup were found to be parabolic; the distribution of local solid particle holdup could be expressed by Eq. (9); liquid interstitial velocity was well described by the modified circulating flow model.展开更多
利用第二次青藏高原科学考察及其他数据,结合5层网格嵌套、高分辨率(最高333 m)的WRF(Weather Research and Forecasting)可分辨云数值模拟,研究了局地山谷风环流在青藏高原东南林芝地区2019年9月17~18日一次地形云和降水形成过程中的...利用第二次青藏高原科学考察及其他数据,结合5层网格嵌套、高分辨率(最高333 m)的WRF(Weather Research and Forecasting)可分辨云数值模拟,研究了局地山谷风环流在青藏高原东南林芝地区2019年9月17~18日一次地形云和降水形成过程中的作用。结果表明,此次降水过程由西风槽天气过境造成,林芝位于西风槽底部,具有弱不稳定层结,云和降水过程呈现明显的午后、傍晚和凌晨三个阶段的变化特征,并且发现局地山谷风环流在这三个阶段的变化中具有重要作用。午后阶段,由于山区强烈的太阳辐射加热,首先产生明显的上坡风和强上谷风环流,在山坡迎风坡受阻挡抬升,并激发出强的地形波,产生了强对流云和降水;傍晚阶段,由于山脉强烈的长波辐射冷却效应,产生的强下坡风在谷底辐合抬升,促进了山谷上空的弱对流、层状云发展;凌晨阶段,下坡风达到最强,产生了强下谷风环流(山风),下坡风在谷底产生强烈的抬升作用,形成深厚的层状云降水过程。展开更多
基金This study was supported by the National Key Programme for Developing Basic Sciences underGrant No. G1998040900-Part 1, and NS
文摘This paper investigates the dry climatology of Sahara and Northwest China deserts from the viewpoint of local meridional circulation with Xie and Arkin rainfall dada and NCAR/NCEP reanalysis data. Results show that there are very dry centers with annual rainfall less than 50 mm over these two deserts while the rainy seasons are very different. In the south part of Sahara desert center and Northwest China desert, over 70% rainfall takes place in June, July and August (JJA). While in the north part of Sahara, rainfall mainly concentrates in December, January and February (DJF). The local biosphere-radiation mechanism proposed by Charney cannot explain the climatology of such very dry centers. Neither can the monsoon-desert mechanism proposed by Rodwell and Hoskins do for the strongest descent center is much more northward than the driest center over Sahara in JJA. From the viewpoint of local meridional circulation, the dryness climatology of Sahara and Northwest China deserts is investigated and compared. It is shown that in DJF, descent of local meridional circulation dominates the two deserts and very dry climate is unavoidable although the relative wet season is weak over the northern part of Sahara due to Mediterranean climate. While in JJA, there is ascent over the two deserts especially over Northwest China. Such ascent can explain the rainy season in south part of Sahara and Northwest China deserts. However, it is the local meridional circulation that takes strong and dry northerly from higher latitudes. The northerly either takes little moisture to the centers or prevents deep and strong convection over the centers. Such local meridional circulation leads to the dry climatology over the two deserts.
基金Natural Science Foundation of China (NSFC,40975057)The Structure of Tibetan Heat Sources and Oscillation Properties in Conjunction with the Mechanism for the Heat Propagating and Influencing as a key project of the NSFC (40633018)Hadley Circulation Anomaly with Its relation to the Anomaly of Summer Climate in China (E3000008098005)
文摘The 1979-2001 ERA-40 monthly mean meridional winds are used to calculate the mass streamfunctions in the monsoon region (60-140° E) and Nio zone (160° E-120° W),with which the climate characteristics and intensity variation of the localized Hadley circulation (LHC) are analyzed over the two regions and the linkage of this LHC to Pacific SST is explored.Evidence suggests as follows.1) The climatological LHC is stronger in the monsoon than in the Nio zone,with its position in the former northward of the latter,especially in the summer half-year.The resulting difference is due mainly to the land-sea heterogeneous distribution and the existence of a cold pool in the equatorial eastern Pacific.2) The LHC experiences a distinct interannual variability in intensity and during 1979-2001 the LHC strength of the two regions changes broadly in an anti-phase manner.3) The LHC has its intensity associated closely with Pacific SST in such a way that its strength anomaly in the monsoon (Nio) band in January is correlated negatively (positively) with the SSTA over the all-Nio (1-4) zone (ANZ) in the equatorial middle and eastern Pacific but positively (negatively) correlated to SSTA in the C-shaped area that surrounds the ANZ.The pattern of July is in rough agreement with that of January,except for more feeble correlativity in July,especially over the monsoon region;4) The ENSO episode has different impacts on the LHC vigor in the two regions.With the occurrence of an El Nio,the LHC is weakened (strengthened) in the monsoon (Nio) region,and the reversal takes place during the La Nia year,with greater anomaly in the Nio area.
文摘In an earlier study, the Atmospheric Models Intercomparison Program (AMIP) simulations of African climate using the nine-layer gridpoint atmospheric general circulation model were found to be closely related to the observed European Centre for Medium Range Weather Forecast (ECMWF) temperature data at 500 and 850 hPa. This paper presents the analysis of the simulation of African climate using the Global Ocean-Atmosphere-Land System Model (IAP/LASG GOALS) and the nine-layer spectral general circulation model rhomboidally truncated at zonal wave number 15 (L9R15) developed at the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, Beijing. Both model simulations were not significantly different from the National Center for Environmental Prediction (NCEP) Reanalysis monthly mean data for 1980-1995 in the case of surface air temperature, sea level pressure and precipitation, with the GOALS reproducing the seasonal mean climate over Africa better. The implications of the encouraging results in developing a local area model for Nigeria have been discussed. The great role of topography in the developing of general circulation models for numerical modelling of weather and climate has been stressed.
基金Supported by the Natural Science Foundation of Chongqing,No. cstc2018jcyj AX0781the Major Project of Chongqing Health Committee,No. cstc2016 shmszx130033031+1 种基金the National Natural Science Foundation of China,No. 81302316the Chongqing technological innovation and application development-Major theme projects,No. cstc2019jscxfxydx0008
文摘BACKGROUND The poly(ADP-ribose)polymerase(PARP)inhibitor olaparib has displayed superior clinical effect in metastatic castration-resistant prostate cancer(mCRPC)patients with the homologous recombination repair(HRR)genes mutations.However,when a patient’s tumor tissue volume is insufficient for genomic profiling of HRR gene mutations,circulating tumor DNA(ctDNA)may be useful in helping to determine and monitor the efficacy of olaparib,as well as in abiraterone-combination treatment,and for understanding any resistance mechanism related to such mutations.CASE SUMMARY A 61-year-old man who was diagnosed with metastatic prostate adenocarcinoma was initially hormone sensitivity,showing high Gleason score(5+5=10)and absolute positive rate(14/14 biopsied specimens).Following failure of several standard therapies,the patient progressed to mCRPC.Surprisingly,the patient showed good response to olaparib-abiraterone-prednisone combination treatment(an androgen-deprivation therapy,provided as the‘final choice’in China).Serum total prostate-specific antigen(TPSA)level reduced and symptoms remitted for 4 months.However,thereafter,serum TPSA levels began slowly increasing,indicating development of olaparib resistance.Subsequent comprehensive genomic profiling of ctDNA, screening 508 cancer-related genes by next-generation sequencing,identified 10 somatic variants as well as 3 copy number alterations. Two identified reversemissense mutations in partner and localizer of BRCA2 (PALB2) may have recovered the readingframe, restoring function of the primary germline PALB2 mutation and causing resistance to thePARP inhibitor olaparib.CONCLUSIONReverse mutations in PALB2, discovered via genomic profiling of ctDNA, may represent apotential resistance mechanism against olaparib in mCRPC.
文摘Radial profiles of local gas and solid holdups and liquid interstitial velocity were measured in a largediameter three-phase fluidized bed, and a systematic study was carried out in comparing the present data with those obtained in small-diameter beds. Radial profiles of local gas holdup were found to be parabolic; the distribution of local solid particle holdup could be expressed by Eq. (9); liquid interstitial velocity was well described by the modified circulating flow model.
文摘利用第二次青藏高原科学考察及其他数据,结合5层网格嵌套、高分辨率(最高333 m)的WRF(Weather Research and Forecasting)可分辨云数值模拟,研究了局地山谷风环流在青藏高原东南林芝地区2019年9月17~18日一次地形云和降水形成过程中的作用。结果表明,此次降水过程由西风槽天气过境造成,林芝位于西风槽底部,具有弱不稳定层结,云和降水过程呈现明显的午后、傍晚和凌晨三个阶段的变化特征,并且发现局地山谷风环流在这三个阶段的变化中具有重要作用。午后阶段,由于山区强烈的太阳辐射加热,首先产生明显的上坡风和强上谷风环流,在山坡迎风坡受阻挡抬升,并激发出强的地形波,产生了强对流云和降水;傍晚阶段,由于山脉强烈的长波辐射冷却效应,产生的强下坡风在谷底辐合抬升,促进了山谷上空的弱对流、层状云发展;凌晨阶段,下坡风达到最强,产生了强下谷风环流(山风),下坡风在谷底产生强烈的抬升作用,形成深厚的层状云降水过程。
