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Monte-Carlo based random passive energy beamforming for reconfigurable intelligent surface assisted wireless power transfer
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作者 Ziyang Lu Yubin Zhao xiaofan li 《Digital Communications and Networks》 SCIE CSCD 2023年第3期667-676,共10页
Reconfigurable intelligent surface(RIS)employs passive beamforming to control the wireless propagation channel,which benefits the wireless communication capacity and the received energy efficiency of wireless power tr... Reconfigurable intelligent surface(RIS)employs passive beamforming to control the wireless propagation channel,which benefits the wireless communication capacity and the received energy efficiency of wireless power transfer(WPT)systems.Such beamforming schemes are classified as discrete and non-convex integer program-ming problems.In this paper,we propose a Monte-Carlo(MC)based random energy passive beamforming of RIS to achieve the maximum received power of electromagnetic(EM)WPT systems.Generally,the Gibbs sampling and re-sampling methods are employed to generate phase shift vector samples.And the sample with the maximum received power is considered the optimal solution.In order to adapt to the application scenarios,we develop two types of passive beamforming algorithms based on such MC sampling methods.The first passive beamforming uses an approximation of the integer programming as the initial sample,which is calculated based on the channel information.And the second one is a purely randomized algorithm with the only total received power feedback.The proposed methods present several advantages for RIS control,e.g.,fast convergence,easy implementation,robustness to the channel noise,and limited feedback requirement,and they are applicable even if the channel information is unknown.According to the simulation results,our proposed methods outperform other approxi-mation and genetic algorithms.With our methods,the WPT system even significantly improves the power effi-ciency in the nonline-of-sight(NLOS)environment. 展开更多
关键词 Reconfigurable intelligence surface Wireless power transfer Monte-carlo algorithm Passive beamforming Gibbs sampling
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Retrospective Analysis of the Effect of Auricular Acupuncture on Pain and Gastrointestinal Motility Recovery After Laparoscopic Surgery for Colorectal Cancer
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作者 xiaofan li Ni Yang +5 位作者 Lei Yu lingzhi Nie Zhixin Xue Yansong Pu Min Wu Junyan Wang 《Proceedings of Anticancer Research》 2023年第3期64-69,共6页
Objective:To investigate the effect of auricular acupuncture on postoperative pain and gastrointestinal motility recovery after laparoscopic surgery for colorectal cancer.Methods:The clinical data of patients who unde... Objective:To investigate the effect of auricular acupuncture on postoperative pain and gastrointestinal motility recovery after laparoscopic surgery for colorectal cancer.Methods:The clinical data of patients who underwent laparoscopic radical surgery for colorectal cancer in our hospital from April 2020 to December 2021 were collected.Based on the inclusion and exclusion criteria,76 patients were included in the retrospective analysis.Depending on whether they received auricular acupuncture or not,the patients were divided into two groups:46 patients in the experimental group(auricular acupuncture)and 30 patients in the control group.The differences between the two groups were analyzed.Results:The time to first flatus of the experimental group was significantly shorter than that of the control group(52.2±7.36 h versus 66.3±7.83 h;P<0.001).Similarly,the time to first defecation of the experimental group was significantly shorter than that of the control group(76.3±7.76 h versus 86.1±10.79 h;P<0.001).The time to first fluid intake of the auricular group was significantly shorter than that of the control group(90.4±8.92 h versus 107.3±9.66 h,P<0.001).Compared with the control group,the experimental group scored significantly lower on the visual analogue scale on postoperative days 2 and 3(P<0.001).Conclusion:Auricular acupuncture is an effective traditional Chinese medicine external treatment method.It can promote gastrointestinal motility recovery in patients after laparoscopic radical surgery for colorectal cancer and also reduce postoperative pain and discomfort.Furthermore,this therapy is easy to operate and well-accepted by patients.Therefore,it should be strongly promoted in clinical practice. 展开更多
关键词 Auricular acupuncture Colorectal cancer LAPAROSCOPY PAIN Postoperative gastrointestinal motility
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Local Torrential Rainfall Event within a Mei-Yu Season Mesoscale Convective System:Importance of Back-Building Processes
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作者 Honglei ZHANG Ming XUE +2 位作者 Hangfeng SHEN xiaofan li Guoqing ZHAI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期847-863,共17页
An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June 2013.This event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 mm.T... An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June 2013.This event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 mm.This rainfall event had two major rainbands.One was caused by a quasi-stationary convective line,and the other by a backbuilding convective line related to the interaction of the outflow boundary from the first rainband and an existing low-level mesoscale convergence line associated with a mei-yu frontal system.The rainfall event lasted 4 h,while the back-building process occurred in 2 h when the extreme rainfall center formed.So far,few studies have examined the back-building processes in the mei-yu season that are caused by the interaction of a mesoscale convergence line and a convective cold pool.The two rainbands are successfully reproduced by the Weather Research and Forecasting(WRF)model with fourlevel,two-way interactive nesting.In the model,new cells repeatedly occur at the west side of older cells,and the backbuilding process occurs in an environment with large CAPE,a low LFC,and plenty of water vapor.Outflows from older cells enhance the low-level convergence that forces new cells.High precipitation efficiency of the back-building training cells leads to accumulated precipitation of over 150 mm.Sensitivity experiments without evaporation of rainwater show that the convective cold pool plays an important role in the organization of the back-building process in the current extreme precipitation case. 展开更多
关键词 torrential rainfall back-building processes numerical simulation trigger mechanism convergence line convective cold pool
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A Modeling Study of Diurnal Rainfall Variations during the 21-Day Period of TOGA COARE 被引量:8
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作者 高守亭 崔晓鹏 xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第5期895-905,共11页
The surface rainfall processes and diurnal variations associated with tropical oceanic convection are examined by analyzing a surface rainfall equation and thermal budget based on hourly zonal-mean data from a series ... The surface rainfall processes and diurnal variations associated with tropical oceanic convection are examined by analyzing a surface rainfall equation and thermal budget based on hourly zonal-mean data from a series of two-dimensional cloud-resolving simulations. The model is integrated for 21 days with imposed large-scale vertical velocity, zonal wind, and horizontal advection obtained from the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) in the control experiment. Diurnal analysis shows that the infrared radiative cooling after sunset, as well as the advective cooling associated with imposed large-scale ascending motion, destabilize the atmosphere and release convective available potential energy to energize nocturnal convective development. Substantial local atmospheric drying is associated with the nocturnal rainfall peak in early morning, which is a result of the large condensation and deposition rates in the vapor budget. Sensitivity experiments show that diurnal variations of radiation and large-scale forcing can produce a nocturnal rainfall peak through infrared and advective cooling, respectively. 展开更多
关键词 diurnal rainfall variation cloud-resolving simulation tropical oceanic convection TOGACOARE
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Clinical antiangiogenic effect of recombinant adenovirus-p53 combined with hyperthermia for advanced cancer 被引量:6
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作者 xiaofan li Shaowen Xiao +1 位作者 Yongheng li Shanwen Zhang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第6期749-755,共7页
Objective: To assess the safety and clinical antiangiogenic effect of recombinant adenovirus-p53 (rAd-p53) combined with hyperthermia plus or not plus radiotherapy in advanced cancer. Methods: Expression of Vascul... Objective: To assess the safety and clinical antiangiogenic effect of recombinant adenovirus-p53 (rAd-p53) combined with hyperthermia plus or not plus radiotherapy in advanced cancer. Methods: Expression of Vascular epithelial growth factor (VEGF) after intratumoral injection of rAd-p53 was assayed by immunohistochemistry (IHC) imaging. Forty-four patients with advanced cancer were enrolled into this clinical study. The patients were intratumorally injected with rAd-p53 (Gendicine) at a dose of 1×1012 vp once a week, with a total of 4-54 (mean 7.7) times. Total of 4-29 (mean 8.5) times of hyperthermia was given to the patients. Among the 44 patients, 30 patients were concurrently added with radiotherapy of a total dose 30-76 Gy/15-38 f/3-8 w (mean 58 Gy). Results: Before and after intratumoral injection of rAd-p53, the VEGF IHC positive cell scores were 2.80 and 1.50, respectively (P=0.031). The treatment of rAd-p53 combined with hyperthermia plus or not plus radiotherapy in advanced cancer achieved CR rate of 13.60% (6/44), and PR rate of 29.6% (13/44), and thus the effective rate was 43.2%. In addition to 6 patients with CR, 19 patients (19/38, 50.0%) had low density area (LDA) of more than 50% area on CT image within tumor indicating tumor tissue necrosis. Conclusions: Our data indicate that rAd-p53 inhibits VEGF expression and angiogenesis, and promotes tumor necrosis and shrinkage induced by hyperthermia plus or not plus radiotherapy in advanced cancer. 展开更多
关键词 Vascular epithelial growth factor (VEGF) recombinant adenovirus-p53 (rAd-p53) advanced cancer HYPERTHERMIA radiotherapy
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Responses of Vertical Structures in Convective and Stratiform Regions to Large-Scale Forcing during the Landfall of Severe Tropical Storm Bilis (2006) 被引量:5
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作者 王东海 xiaofan li Wei-Kuo TAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第1期33-46,共14页
The responses of vertical structures, in convective and stratiform regions, to the large-scale forcing during the landfall of tropical storm Bilis (2006) are investigated using the data from a two-dimensional cloud-... The responses of vertical structures, in convective and stratiform regions, to the large-scale forcing during the landfall of tropical storm Bilis (2006) are investigated using the data from a two-dimensional cloud-resolving model simulation. An imposed large-scale forcing with upward motion in the mid and upper troposphere and downward motion in the lower troposphere on 15 July suppresses convective clouds, which leads to -100% coverage of raining stratiform clouds over the entire model domain. The imposed forcing extends upward motion to the lower troposphere during 16-17 July, which leads to an enhancement of convective clouds and suppression of raining stratiform clouds. The switch of large-scale lower-tropospheric vertical velocity from weak downward motion on 15 July to moderate upward motion during 16-17 July produces a much broader distribution of the vertical velocity, water vapor and hydrometeor fluxes, perturbation specific humidity, and total hydrometeor mixing ratio during 16-17 July than those on 15 July in the analysis of contoured frequency-altitude diagrams. Further analysis of the water vapor budget reveals that local atmospheric moistening is mainly caused by the enhancement of evaporation of rain associated with downward motion on 15 July, whereas local atmospheric drying is mainly determined by the advective drying associated with downward motion over raining stratiform regions and by the net condensation associated with upward motion over convective regions during 16-17 July. 展开更多
关键词 cloud-resolving simulation large-scale vertical velocity water vapor and hydrometeor mass fluxes heat budgets
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Water Vapor,Cloud,and Surface Rainfall Budgets Associated with the Landfall of Typhoon Krosa(2007):A Two-Dimensional Cloud-Resolving Modeling Study 被引量:3
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作者 岳彩军 寿绍文 xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第6期1198-1208,共11页
Water vapor, cloud, and surface rainfall budgets associated with the landfall of Typhoon Krosa on 6-8 October 2007 are analyzed based on a two-dimensional cloud-resolving model simulation. The model is integrated with... Water vapor, cloud, and surface rainfall budgets associated with the landfall of Typhoon Krosa on 6-8 October 2007 are analyzed based on a two-dimensional cloud-resolving model simulation. The model is integrated with imposed zonally-uniform vertical velocity, zonal wind, horizontal temperature, and vapor advection from NCEP/Global Data Assimilation System (GDAS) data. The simulation data that are validated with observations are examined to study physical causes associated with surface rainfall processes during the landfall. The time- and domain-mean analysis shows that when Krosa approached the eastern coast of China on 6 October, the water vapor convergence over land caused a local atmospheric moistening and a net condensation that further produced surface rainfall and an increase of cloud hydrometeor concentration. Meanwhile, latent heating was balanced by advective cooling and a local atmospheric warming. One day later, the enhancement of net condensation led to an increase of surface rainfall and a local atmospheric drying, while the water vapor convergence weakened as a result of the landfall-induced deprivation of water vapor flux. At the same time, the latent heating is mainly compensated the advective cooling. Further weakening of vapor convergence on 8 October enhanced the local atmospheric drying while the net condensation and associated surface rainfall was maintained. The latent heating is balanced by advective cooling and a local atmospheric cooling. 展开更多
关键词 BUDGET cloud-resolving modeling Typhoon Krosa
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The coefficient of variation representing the non-uniformity of the strain field and its implication to detect earthquake precursor
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作者 Yonghong Zhao Yue Zhao +3 位作者 xiaofan li Zhongcheng Cao Zhen li Muhammad Irfan Ehsan 《Earthquake Science》 2020年第5期246-255,共10页
Before the major earthquake or rock damage occurs,it is often accompanied by a sudden change in the degree of non-uniformity of the strain field.In order to find a stronger non-uniformity signal before the rock failur... Before the major earthquake or rock damage occurs,it is often accompanied by a sudden change in the degree of non-uniformity of the strain field.In order to find a stronger non-uniformity signal before the rock failure,the coefficient of variation(Cv)is examined and reformed in this study.We test the Cv calculation way of the"normal-abnormal"model proposed in the previous studies.Based on the analysis of the physical process of rock failure and its relationship to the shear strain field,we construct a new way to calculate the Cv value.The variation of shear strain field on rock sample with the increase of stress is obtained by the digital speckle correlation method(DSCM).The new Cv value calculation way is used to study the non-uniformity of the spatial distribution for the shear strain field.The results show that this Cv calculation way can get more obvious abnormal signals.When the number of observation points are limited,the specific distribution of points can increase the signal strength,which may provide reference for the research on precursor detection of earthquakes. 展开更多
关键词 rock failure shear strain field NON-UNIFORMITY coefficient of variation
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山东地区一次夏季极端暴雨中尺度系统发展演变过程及机理分析 被引量:4
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作者 龚琬丁 周玉淑 +3 位作者 钟珊珊 沈新勇 李小凡 邓国 《大气科学》 CSCD 北大核心 2023年第3期786-804,共19页
对2020年7月22日山东半岛一次极端暴雨天气过程开展观测分析,并利用中尺度模式WRF对此次局地降水过程进行了高分辨率数值模拟,对暴雨过程进行了天气背景和中尺度降雨的诊断。WRF模式较好地再现了此次极端暴雨过程,结果表明:此次极端暴... 对2020年7月22日山东半岛一次极端暴雨天气过程开展观测分析,并利用中尺度模式WRF对此次局地降水过程进行了高分辨率数值模拟,对暴雨过程进行了天气背景和中尺度降雨的诊断。WRF模式较好地再现了此次极端暴雨过程,结果表明:此次极端暴雨过程短时降水强度大且局地性强,在时空上具有明显中尺度特征。降水发生在北抬副热带高压与华北低涡底部之间的西南气流中,强低涡与低空急流是影响此次降水的重要天气系统。西南急流为本次暴雨过程极端水汽的主要输送载体;在弱高空辐散场下,从地表延伸至500 hPa高空的深厚低涡是造成本次暴雨的主要影响因子,其时空演变特征与中尺度云团变化一致,与暴雨的发生直接相关。低涡、低空急流和副高之间的相互作用使低涡加强发展,低涡南部有暖湿气流入流,北部有干冷气流流入,比湿梯度基本呈现为自南向北递减分布,是典型的伴有低空急流的中尺度低涡流场分布;低涡辐合及其与副热带高压边缘强风速带的共同作用,导致强垂直运动发展并维持,是造成本次山东半岛极端暴雨的重要原因。 展开更多
关键词 山东半岛 极端暴雨 中尺度低涡 低空急流 发展演变过程
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气候态调整对华北冬、夏季气候监测的影响研究 被引量:1
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作者 李晓帆 于长文 +3 位作者 龚志强 封国林 车少静 李天宇 《大气科学》 CSCD 北大核心 2023年第3期599-615,共17页
本研究对比分析了不同气候态下,华北冬、夏季降水及气温的差异,分析了气候平均值的改变对历史极端事件监测的可能影响。研究结果发现,1991~2020年(简称气候Ⅱ态)的冬季和夏季的平均降水量均略多于1981~2010年(简称气候Ⅰ态),但接近或略... 本研究对比分析了不同气候态下,华北冬、夏季降水及气温的差异,分析了气候平均值的改变对历史极端事件监测的可能影响。研究结果发现,1991~2020年(简称气候Ⅱ态)的冬季和夏季的平均降水量均略多于1981~2010年(简称气候Ⅰ态),但接近或略少于1961~2020年的平均降水量,平均降水量逐年变化幅度冬季Ⅱ态小于Ⅰ态,夏季反之。气候Ⅱ态冬季降水空间分布不均,夏季较Ⅰ态呈“中部减少,东西增加”的分布型。冬季和夏季极端降水阈值Ⅱ态(0.86 mm和22.0 mm)较Ⅰ态(0.83 mm和21.6 mm)均略有提高,造成近60年华北大部基于Ⅱ态阈值的冬、夏季极端降水日数较Ⅰ态略减少。此外,气候Ⅱ态的华北冬、夏季平均气温均明显高于Ⅰ态,也高于1961~2020年平均值。Ⅱ态气温较Ⅰ态基本呈全区增加特征,但空间分布不均匀。冬季极端低温和夏季极端高温阈值Ⅱ态(-9.8℃和27.9℃)较Ⅰ态(-10.2℃和27.5℃)均有所有所提高,造成华北大部分地区基于Ⅱ态阈值的近60年冬季极端低温日数较Ⅰ态有所增加,夏季极端高温日数较Ⅰ态存在不同程度的减少。因此,新气候态下华北气温和降水均值,华北大部极端降水阈值和极端气温阈值均有所提高,造成气候监测中更容易出现气温偏低,降水偏少,历史极端事件监测中极端事件略减少的情况,在未来10年的气候监测预测业务中要充分考虑新气候态可能造成的影响。 展开更多
关键词 华北 冬季 夏季 气候态差异
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Predecessor Rain Events in the Yangtze River Delta Region Associated with South China Sea and Northwest Pacific Ocean(SCS-WNPO)Tropical Cyclones 被引量:2
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作者 Huiyan XU xiaofan li +1 位作者 Jinfang YIN Dengrong ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第6期1021-1042,共22页
Predecessor rain events(PREs) in the Yangtze River Delta(YRD) region associated with the South China Sea and Northwest Pacific Ocean(SCS-WNPO) tropical cyclones(TCs) are investigated during the period from 2010 to 201... Predecessor rain events(PREs) in the Yangtze River Delta(YRD) region associated with the South China Sea and Northwest Pacific Ocean(SCS-WNPO) tropical cyclones(TCs) are investigated during the period from 2010 to 2019.Results indicate that approximately 10% of TCs making landfall in China produce PREs over the YRD region;however,they are seldom forecasted. PREs often occur over the YRD region when TCs begin to be active in the SCS-WNPO with westward paths, whilst the cold air is still existing or beginning to be present. PREs are more likely to peak in June and September. The distances between the PRE centers and the parent TC range from 900 to 1700 km. The median value of rain amounts and the median lifetime of PREs is approximately 200 mm and 24 h, respectively. Composite results suggest that PREs form in the equatorward jet-entrance region of the upper-level westerly jet(WJ), where a 925-hPa equivalent potential temperature ridge is located east of a 500-hPa trough. Deep moisture is transported from the TC vicinity to the remote PREs region. The ascent of this deep moist air in front of the 500-hPa trough and frontogenesis beneath the equatorward entrance region of the WJ is advantageous for the occurrence of PREs in the YRD region. The upper-level WJ may be affected by the subtropical high and westerly trough in the Northwest Pacific Ocean, and the occurrence of PREs may favor the maintenance of the upper-level WJ. The upper-level outflow of TCs in the SCS plays a secondary role. 展开更多
关键词 tropical cyclone heavy rain westerly trough upper-level jet stream
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Kinetic Energy Budgets during the Rapid Intensification of Typhoon Rammasun (2014)
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作者 Xin QUAN xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期78-94,共17页
In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the ... In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the typhoon,the conversion from symmetric divergent kinetic energy associated with the collocation of strong cyclonic circulation and inward flow led to an increase in the symmetric rotational kinetic energy in the lower troposphere.The increase in the symmetric rotational kinetic energy in the mid and upper troposphere resulted from the upward transport of symmetric rotational kinetic energy from the lower troposphere.In the outer area,both typhoon and Earth’s rotation played equally important roles in the conversion from symmetric divergent kinetic energy to symmetric rotational kinetic energy in the lower troposphere.The decrease in the symmetric rotational kinetic energy in the upper troposphere was caused by the conversion to asymmetric rotational kinetic energy through the collocation of symmetric tangential rotational winds and the radial advection of asymmetric tangential rotational winds by radial environmental winds. 展开更多
关键词 Typhoon Rammasun(2014) rapid intensification kinetic energy budget symmetric and asymmetric winds divergent and rotational circulations environmental flows
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Experimental study on strain field evolution around a simulated thrust fault
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作者 Yonghong Zhao Yanjun Xiao +2 位作者 Jiaying Yang xiaofan li Andong Xu 《Earthquake Science》 2023年第1期40-51,共12页
Earthquakes result from continuous geodynamic processes.A topic of significant interest for the scientific community is to elaborate on the phenomena governing the faulting and fracturing of crustal rocks.Therefore,in... Earthquakes result from continuous geodynamic processes.A topic of significant interest for the scientific community is to elaborate on the phenomena governing the faulting and fracturing of crustal rocks.Therefore,in this study,uniaxial compressive shear failure experiments were conducted on Fangshan marble rock samples with a prefabricated slot to simulate thrust faulting.The center of each marble plate(105 mm × 80 mm × 5 mm) was engraved with a 30-mm long double-sided nonpenetrating slot(depth:2 mm,width:0.5 mm).The deformation and destruction processes of the rock surface were recorded using a high-speed camera.The digital image correlation method was used to calculate the displacement and strain distribution and variation at different loading stages.The accumulative and incremental displacement fields u and v,strain field exand e_(y),and shear strain e_(xy) were analyzed.When the loading level reached its ultimate value,the strain field was concentrated around the prefabricated slot.The concentration reached a maximum at the ends of the prefabricated slot.The magnitude of shear strain reached 0.1.This experiment contributes to our understanding of the dynamic process of active faulting. 展开更多
关键词 experimental study deformation field evolution fracture process EARTHQUAKE
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Achieving robust synthetic tolerance in industrial E.coli through negative auto-regulation of a DsrA-Hfq module
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作者 Xiaofeng Yang Jingduan Yang +3 位作者 Haozheng Huang xiaofang Yan xiaofan li Zhanglin lin 《Synthetic and Systems Biotechnology》 SCIE CSCD 2024年第3期462-469,共8页
In industrial fermentation processes,microorganisms often encounter acid stress,which significantly impact their productivity.This study focused on the acid-resistant module composed of small RNA(sRNA)DsrA and the sRN... In industrial fermentation processes,microorganisms often encounter acid stress,which significantly impact their productivity.This study focused on the acid-resistant module composed of small RNA(sRNA)DsrA and the sRNA chaperone Hfq.Our previous study had shown that this module improved the cell growth of Escherichia coli MG1655 at low pH,but failed to obtain this desired phenotype in industrial strains.Here,we performed a quantitative analysis of DsrA-Hfq module to determine the optimal expression mode.We then assessed the po-tential of the CymR-based negative auto-regulation(NAR)circuit for industrial application,under different media,strains and pH levels.Growth assay at pH 4.5 revealed that NAR-05D04H circuit was the best acid-resistant circuit to improve the cell growth of E.coli MG1655.This circuit was robust and worked well in the industrial lysine-producing strain E.coli SCEcL3 at a starting pH of 6.8 and without pH control,resulting in a 250%increase in lysine titer and comparable biomass in shaking flask fermentation compared to the parent strain.This study showed the practical application of NAR circuit in regulating DsrA-Hfq module,effectively and robustly improving the acid tolerance of industrial strains,which provides a new approach for breeding in-dustrial strains with tolerance phenotype. 展开更多
关键词 Acid-resistant Synthetic tolerance DsrA-Hfq Negative auto-regulation Robustness
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Radiative Effects on Torrential Rainfall during the Landfall of Typhoon Fitow(2013) 被引量:3
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作者 lingyun LOU xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第1期101-109,共9页
Cloud microphysical and rainfall responses to radiative processes are examined through analysis of cloud-resolving model sensitivity experiments of Typhoon Fitow(2013) during landfall.The budget analysis shows that ... Cloud microphysical and rainfall responses to radiative processes are examined through analysis of cloud-resolving model sensitivity experiments of Typhoon Fitow(2013) during landfall.The budget analysis shows that the increase in the mean rainfall caused by the exclusion of radiative effects of water clouds corresponds to the decrease in accretion of raindrops by cloud ice in the presence of radiative effects of ice clouds,but the rainfall is insensitive to radiative effects of water clouds in the absence of radiative effects of ice clouds.The increases in the mean rainfall resulting from the removal of radiative effects of ice clouds correspond to the enhanced net condensation.The increases(decreases) in maximum rainfall caused by the exclusion of radiative effects of water clouds in the presence(absence) of radiative effects of ice clouds,or the removal of radiative effects of ice clouds in the presence(absence) of radiative effects of water clouds,correspond mainly to the enhancements(reductions) in net condensation.The mean rain rate is a product of rain intensity and fractional rainfall coverage.The radiation-induced difference in the mean rain rate is related to the difference in rain intensity.The radiation-induced difference in the maximum rain rate is associated with the difference in the fractional coverage of maximum rainfall. 展开更多
关键词 radiative effects RAINFALL maximum rainfall rain intensity fractional rainfall coverage net condensation hydrometeor change
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Torrential Rainfall Responses to Ice Microphysical Processes during Pre-Summer Heavy Rainfall over Southern China 被引量:5
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作者 沈新勇 刘佳 xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第3期493-500,共8页
In this study, the effects of key ice microphysical processes on the pre-summer heavy rainfall over southern China during 3-8 June 2008 were investigated. A series of two-dimensional sensitivity cloud-resolving model ... In this study, the effects of key ice microphysical processes on the pre-summer heavy rainfall over southern China during 3-8 June 2008 were investigated. A series of two-dimensional sensitivity cloud-resolving model simulations were forced with zonally uniform vertical velocity, zonal wind, horizontal temperature, and water vapor advection data from the National Centers for Environmental Prediction (NCEP)/Global Data Assimilation System (GDAS). The effects of key ice microphysical processes on the responses of rainfall to large-scale forcing were analyzed by comparing two sensitivity experiments with a control experiment. In one sensitivity experiment, ice crystal radius, associated with depositional growth of snow from cloud ice, was reduced from 100 #m in the control experiment to 50 #m, and in the other sensitivity experiment the efficiency of the growth of graupel from the accretion of snow was reduced to 50~ from 100% in the control experiment. The results show that the domain-mean rainfall responses to these ice microphysical processes are stronger during the decay phase than during the onset and mature phases. During the decay phase, the increased mean rain rate resulting from the decrease in ice crystal radius is associated with the enhanced mean local atmospheric drying, the increased mean local hydrometeor loss, and the suppressed mean water vapor divergence. The increased mean rain rate caused by the reduction in accretion efficiency is related to the reduced mean water vapor divergence and the enhanced mean local hydrometeor loss. 展开更多
关键词 ice crystal radius accretion efficiency cloud-resolving model simulation
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A Review of Cloud-Resolving Model Studies of Convective Processes 被引量:4
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作者 Xiaoqing WU xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第2期202-212,共11页
Convective processes affect large-scale environments through cloud-radiation interaction, cloud micro- physical processes, and surface rainfall processes. Over the last three decades, cloud-resolving models (CRMs) h... Convective processes affect large-scale environments through cloud-radiation interaction, cloud micro- physical processes, and surface rainfall processes. Over the last three decades, cloud-resolving models (CRMs) have demonstrated to be capable of simulating convective-radiative responses to an imposed large-scale forcing. The CRM-produced cloud and radiative properties have been utilized to study the convective- related processes and their ensemble effects on large-scale circulations. This review the recent progress on the understanding of convective processes with the use of CRM simulations, including precipitation processes; cloud microphysical and radiative processes; dynamical processes; precipitation efficiency; diurnal variations of tropical oceanic convection; local-scale atmosphere-ocean coupling processes; and tropical convective-radiative equilibrium states. Two different ongoing applications of CRMs to general circulation models (GCMs) are discussed: replacing convection and cloud schemes for studying the interaction between cloud systems and large-scale circulation, and improving the schemes for climate simulations. 展开更多
关键词 cloud-resolving models (CRMs) convective processes simulations of convection and clouds
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Age-related modifications of macrophages influenced by “inflammageing”in graft vs. host disease 被引量:2
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作者 YAQUN HONG BO WAN xiaofan li 《BIOCELL》 SCIE 2020年第2期237-246,共10页
Most studies focus on the adaptive immune cells in the GVHD pathogenesis,while little is known about innate immune cells in GVHD occurrence and development,especially macrophages.Meanwhile,a higher incidence of graft ... Most studies focus on the adaptive immune cells in the GVHD pathogenesis,while little is known about innate immune cells in GVHD occurrence and development,especially macrophages.Meanwhile,a higher incidence of graft versus host disease(GVHD)is also found in the elderly patients.Though advances have been made in the modification of macrophages influenced by the inflamm-ageing,there is still no review on the role of macrophages in GVHD and the association between GVHD and the altered macrophages by inflamm-ageing.In this review,we focus on the potential age-related modifications of macrophage in GVHD,which contributes to the change of morbidity and mortality of GVHD.Via literature review,we found that the infiltration of macrophages is associated with GVHD and macrophages are modified in inflamm-ageing state,including the proliferation,migration,phagocytosis,antigen presentation,interaction with other immune cells,and pro-fibrosis.We suppose that altered macrophage functions in inflamm-ageing state contribute to GVHD in elderly patients. 展开更多
关键词 MACROPHAGES Inflamm-ageing GRAFT VS HOST DISEASE Hematopoietic stem cell transplantation Age Innate immune cells
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Impacts of Initial Conditions on Cloud-Resolving Model Simulations 被引量:3
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作者 高守亭 xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第5期737-747,共11页
Impacts of initial conditions on cloud-resolving model simulations are investigated using a series of sensitivity experiments. Five experiments with perturbed initial temperature, moisture, and cloud conditions are co... Impacts of initial conditions on cloud-resolving model simulations are investigated using a series of sensitivity experiments. Five experiments with perturbed initial temperature, moisture, and cloud conditions are conducted and compared to the control experiment. The model is forced by the large-scale vertical velocity and zonal wind observed and derived from NCEP/Global Data Assimilation System (GDAS). The results indicate that model predictions of rainfall are much more sensitive to the initial conditions than those of temperature and moisture. Further analyses of the surface rainfall equation and the moisture and cloud hydrometeor budgets reveal that the calculations of vapor condensation and deposition rates in the model account for the large sensitivities in rainfall simulations. 展开更多
关键词 cloud-resolving model initial conditions sensitivity experiments
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An Analysis of Thermally-Related Surface Rainfall Budgets Associated with Convective and Stratiform Rainfall 被引量:2
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作者 周玉淑 xiaofan li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第5期1099-1108,共10页
Both water vapor and heat processes play key roles in producing surface rainfall.While the water vapor effects of sea surface temperature and cloud radiative and microphysical processes on surface rainfall have been i... Both water vapor and heat processes play key roles in producing surface rainfall.While the water vapor effects of sea surface temperature and cloud radiative and microphysical processes on surface rainfall have been investigated in previous studies,the thermal effects on rainfall are analyzed in this study using a series of two-dimensional equilibrium cloud-resolving model experiments forced by zonally-uniform,constant,large-scale zonal wind and zero large-scale vertical velocity.The analysis of thermally-related surface rainfall budget reveals that the model domain mean surface rain rate is primarily associated with the mean infrared cooling rate.Convective rainfall and transport of hydrometeor concentration from convective regions to raining stratiform regions corresponds to the heat divergence over convective regions,whereas stratiform rainfall corresponds to the transport of hydrometeor concentration from convective regions and heat divergence over raining stratiform regions.The heat divergence over convective regions is mainly balanced by the heat convergence over rainfall-free regions,which is,in turn,offset by the radiative cooling over rainfall-free regions.The sensitivity experiments of rainfall to the effects of sea surface temperature and cloud radiative and microphysical processes show that the sea surface temperature and cloud processes affect convective rainfall through the changes in infrared cooling rate over rainfall-free regions and transport rate of heat from convective regions to rainfall-free regions. 展开更多
关键词 surface rainfall infrared cooling heat divergence cloud-resolving model simulation
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