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| 1 | A new approach to the generation of initial perturbations for ensemble prediction:Conditional nonlinear optimal perturbation显示文摘Conditional nonlinear optimal perturbation (CNOP),which is a natural extension of singular vector (SV) into the nonlinear regime,is applied to ensemble prediction study by using a quasi-geostrophic model under the perfect model assumption. SVs and CNOPs have been utilized to generate the initial pertur-bations for ensemble prediction experiments. The results are compared for forecast lengths of up to 14 d. It is found that the forecast skill of samples,in which the first SV is replaced by CNOP,is com-paratively higher than that of samples composed of only SVs in the medium range (day 6―day 14). This conclusion is valid under the condition that analysis error is a kind of fast-growing ones regardless of its magnitude,whose nonlinear growth is faster than that of SV in the later part of the forecast. Fur-thermore,similarity index and empirical orthogonal function (EOF) analysis are performed to explain the above numerical results. | MU Mu JIANG ZhiNa | 2008 | Chinese Science Bulletin2008，53，13： | 39 |
| 2 | IL-37b suppresses T cell priming by modulating dendritic cell maturation and cytokine production via dampening ERK/NF-κB/S6K signalings显示文摘Interleukin 37b (IL-37b ) 在压制有免疫力的回答起一个关键作用,部分由 modulating 树枝状的房间(DC ) 的功能。然而,精确机制大部分仍然是未知的。这里,我们在回答由 DC 导致了的 DC 成熟和 T 房间上调查了 IL-37b 的效果,并且探索了深奥发信号的小径。它被发现那 IL-37b 下面调整在 vitro 的 DC 上的 co-stimulatory 分子 CD80 和 CD86 的表情。同时,支持 inflammatory cytokines 的表情例如 TNF-6, 和 IL-6,被压制,当时 T 房间的表示禁止的 cytokine TGF- 在 IL-37b-treated DC 被增加。另外, T 房间上的 DC 的激活效果被 IL-37b 损害。我们进一步表明细胞外的调整单人赛的 kinase (英皇家空军之阶级最低之兵) ,原子 factor-B (NF-B ) ,和表明小径的 mTOR-S6K 涉及 IL-37b 导致的 DC 的抑制。这被化学禁止者的同样镇压的效果在 DC 在 IL-6 和 TNF- 的表情上对 NF-B,英皇家空军之阶级最低之兵,和 S6K 证实。在结论,这些结果证明 IL-37b 由在英皇家空军之阶级最低之兵, NF-B,和基于 S6K 的禁止的发信号小径包含在 T 房间 priming 压制了 DC 成熟和 immunostimulatory 能力。 | Wantong Wu Weiqiang Wang Yun Wang Wenwen Li Gang Yu Zhonglong Li Chunmin Fang Yue Shen Zhina Sun Ling Han Juan Yu Lijun Fang Song Chen Kui Dong Zhongchao Han Hanzhi Liu Yuechen Luo Xiaoming Feng | 2015 | Acta Biochimica et Biophysica Sinica2015，47，8： | 8 |
| 3 | Surface effects on a mode-III reinforced nano-elliptical hole embedded in one-dimensional hexagonal piezoelectric quasicrystals显示文摘To effectively reduce the field concentration around a hole or crack,an anti-plane shear problem of a nano-elliptical hole or a nano-crack pasting a reinforcement layer in a one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)is investigated subject to remotely mechanical and electrical loadings.The surface effect and dielectric characteristics inside the hole are considered for actuality.By utilizing the technique of conformal mapping and the complex variable method,the phonon stresses,phason stresses,and electric displacements in the matrix and reinforcement layer are exactly derived under both electrically permeable and impermeable boundary conditions.Three size-dependent field intensity factors near the nano-crack tip are further obtained when the nano-elliptical hole is reduced to the nano-crack.Numerical examples are illustrated to show the effects of material properties of the surface layer and reinforced layer,the aspect ratio of the hole,and the thickness of the reinforcing layer on the field concentration of the nano-elliptical hole and the field intensity factors near the nano-crack tip.The results indicate that the properties of the surface layer and reinforcement layer and the electrical boundary conditions have great effects on the field concentration of the nano-hole and nano-crack,which are useful for optimizing and designing the microdevices by PQC nanocomposites in engineering practice. | Zhina ZHAO Junhong GUO | 2021 | Applied Mathematics and Mechanics(English Edition)2021，42，5： | 6 |
| 4 | Ensemble prediction experiments using conditional nonlinear optimal perturbation显示文摘Two methods for initialization of ensemble forecasts are compared, namely, singular vector (SV) and conditional nonlinear optimal perturbation (CNOP). The comparison is done for forecast lengths of up to 10 days with a three-level quasi-geostrophic (QG) atmospheric model in a perfect model scenario. Ten cases are randomly selected from 1982/1983 winter to 1993/1994 winter (from December to the following February). Anomaly correlation coefficient (ACC) is adopted as a tool to measure the quality of the predicted ensembles on the Northern Hemisphere 500 hPa geopotential height. The results show that the forecast quality of ensemble samples in which the first SV is replaced by CNOP is higher than that of samples composed of only SVs in the medium range, based on the occurrence of weather re-gime transitions in Northern Hemisphere after about four days. Besides, the reliability of ensemble forecasts is evaluated by the Rank Histograms. The above conclusions confirm and extend those reached earlier by the authors, which stated that the introduction of CNOP improves the forecast skill under the condition that the analysis error belongs to a kind of fast-growing error by using a barotropic QG model. | JIANG ZhiNa MU Mu WANG DongHai | 2009 | Science China Earth Sciences2009，52，4： | 4 |
| 5 | Roles of Synoptic to Quasi-Monthly Disturbances in Generating Two Pre-Summer Heavy Rainfall Episodes over South China显示文摘In this study,power spectral analysis and bandpass filtering of daily meteorological fields are performed to explore the roles of synoptic to quasi-monthly disturbances in influencing the generation of pre-summer heavy rainfall over South China.Two heavy rainfall episodes are selected during the months of April-June 2008-15,which represent the collaboration between the synoptic and quasi-biweekly disturbances and the synoptic and quasi-monthly disturbances,respectively.Results show that the first heavy rainfall episode takes place in a southwesterly anomalous flow associated with an anticyclonic anomaly over the South China Sea(SCS)at the quasi-biweekly scale with 15.1%variance contributions,and at the synoptic scale in a convergence zone between southwesterly and northeasterly anomalous flows associated with a southeastward-moving anticyclonic anomaly on the leeside of the Yungui Plateau and an eastwardpropagating anticyclonic anomaly from higher latitudes with 35.2%variance contribution.In contrast,the second heavy rainfall episode takes place in southwest-to-westerly anomalies converging with northwest-to-westerly anomalies at the quasi-monthly scale with 23.2%variance contributions to the total rainfall variance,which are associated with an anticyclonic anomaly over the SCS and an eastward-propagating cyclonic anomaly over North China,respectively.At the synoptic scale,it occurs in south-to-southwesterly anomalies converging with a cyclonic anomaly on the downstream of the Yungui Plateau with 49.3%variance contributions.In both cases,the lower-tropospheric mean south-to-southwesterly flows provide ample moisture supply and potentially unstable conditions;it is the above synoptic,quasi-biweekly or quasimonthly disturbances that determine the general period and distribution of persistent heavy rainfall over South China. | Zhina JIANG Da-Lin ZHANG Hongbo LIU | 2020 | Advances in Atmospheric Sciences2020，37，2： | 2 |
| 6 | Exploring the Phase-Strength Asymmetry of the North Atlantic Oscillation Using Conditional Nonlinear Optimal Perturbation显示文摘Negative-phase North Atlantic Oscillation(NAO) events are generally stronger than positive-phase ones, i.e., there is a phase-strength asymmetry of the NAO. In this work, we explore this asymmetry of the NAO using the conditional nonlinear optimal perturbation(CNOP) method with a three-level global quasi-geostrophic spectral model. It is shown that, with winter climatological flow forcing, the CNOP method identifies the perturbations triggering the strongest NAO event under a given initial constraint. Meanwhile, the phase-strength asymmetry characteristics of the NAO can be revealed. By comparing with linear results, we find that the process of perturbation self-interaction promotes the onset of negative NAO events, which is much stronger than during positive NAO onset. Results are obtained separately using the climatological and zonal-mean flows in boreal winter(December–February) 1979–2006 as the initial basic state. We conclude, based on the fact that NAO onset is a nonlinear initial-value problem, that phase-strength asymmetry is an intrinsic characteristic of the NAO. | JIANG Zhina WANG Xin WANG Donghai | 2015 | Advances in Atmospheric Sciences2015，32，5： | 2 |
| 7 | Growth asymmetry precedes differential auxin response during apical hook initiation in Arabidopsis显示文摘The development of a hook-like structure at the apical part of the soil-emerging organs has fascinated botanists for centuries,but how it is initiated remains unclear.Here,we demonstrate with highthroughput infrared imaging and 2-D clinostat treatment that,when gravity-induced root bending is absent,apical hook formation still takes place.In such scenarios,hook formation begins with a de novo growth asymmetry at the apical part of a straightly elongating hypocotyl.Remarkably,suchde novo asymmetric growth,but not the following hook enlargement,precedes the establishment of a detectable auxin response asymmetry,and is largely independent of auxin biosynthesis,transport and signaling.Moreover,we found that functional cortical microtubule array is essential for the following enlargement of hook curvature.When microtubule array was disrupted by oryzalin,the polar localization of PIN proteins and the formation of an auxin maximum became impaired at the to-be-hook region.Taken together,we propose a more comprehensive model for apical hook initiation,in which the microtubuledependent polar localization of PINs may mediate the instruction of growth asymmetry that is either stochastically taking place,induced by gravitropic response,or both,to generate a significant auxin gradient that drives the full development of the apical hook. | Yang Peng Dan Zhang Yuping Qiu Zhina Xiao Yusi Ji Wenyang Li Yiji Xia Yichuan Wang Hongwei Guo | 2022 | Journal of Integrative Plant Biology2022，64，1： | 1 |
| 8 | A Possible Mechanism for Winter Sea Ice Decline over the Bering Sea and Its Relationship with Cold Events over North America显示文摘In this study,the mechanism for the sea ice decline over the Bering Sea and its relationship with cold events over North America are investigated based on the daily ERA-Interim data during the winter(December-February)of1979-2016.The results show that the sea ice decline over western(eastern)Bering Sea is mainly contributed by(1)the strengthened southerly(southeasterly)wind near the surface,which possibly pushes the sea ice to move northward,and(2)the intensified downward infrared radiation(IR),which is closely related to the local increasing surface air temperature(SAT)and the intensified moisture convergence mostly induced by the anomalous southeasterly wind associated with an anticyclonic anomaly over the Alaska Bay.During the sea ice decline over the Bering Sea,a cold SAT anomaly is simultaneously found over North America.It is proved that the occurrence of such a cold event is driven by the atmospheric internal variation,but not the forcing of sea ice decline over the Bering Sea.This study deepens our understanding of sea ice decline and its relationship with contemporary cold events in winter. | Wenqin ZHUO Zhina JIANG | 2020 | Journal of Meteorological Research2020，34，3： | 1 |
| 9 | Improvement of straw surface characteristics via thermomechanical and chemical treatments显示文摘 | Mingzhu Pan Dingguo Zhou Xiaoyan Zhou Zhina Lian | 2010 | Bioresource Technology2010，，20： | 1 |
| 10 | Wheat yield convergence and its driving factors in countries along the Belt and Road显示文摘Improving the wheat yield of countries along the Belt and Road(BR)plays a core role in ensuring global food security.However,little attention has been paid to the wheat yield variation and the determinants across these countries.This paper analyzes wheat yield convergence in countries along the BR using the club-convergence test.The empirical results show that instead of one convergence for all countries along the BR,the wheat yields are converging into three clubs.Furthermore,we investigate the impact of climate change and agricultural production technology on wheat yield convergence,and find that countries along the BR with a one degree Celsius increase in temperature are 36.5%(32.7%)more likely to converge to the high-level yield club.This may be related to the lower frequency of frost and higher photosynthetic capacity of wheat.We also find that a one kilogram increase in fertilizer application per hectare will result in a 0.4%(0.5%)higher probability of countries along the BR converging to the high-level yield club.Countries along the BR should pay more attention to coordinating production technologies and climate change to ensure food security. | Xiaoheng Zhang Zhina Wang Ping Qing Dieter Koemle Xiaohua Yu | 2020 | Ecosystem Health and Sustainability2020，6，1： | 1 |
| 11 | Possible Links between Arctic Sea Ice Loss Events and Cold Eurasian Anomalies in Winter显示文摘Recently,there have been two competing perspectives on the links of rapid sea ice retreat over the Barents–Kara Seas(BKS)and in midlatitude severe cold winters over Eurasia.By using the daily ECMWF reanalysis(ERA)-Interim dataset during 1979–2016,we reconcile two contrasting viewpoints,namely,if an upward turbulent heat flux appears and maintains several days after the rapid sea ice loss over the BKS in winter,a dipole structure which consists of a primary positive center of action around the Barents Sea with the other opposite-sign center of action over Eurasian continent is easily amplified,and consequently a cold anomaly over Eurasia will occur,but not vice versa.Our work casts light on the links between the Arctic sea ice loss and Eurasian cold winter anomalies by revealing the different responses of the surface turbulent heat flux(STHF)after rapid sea ice retreat on a daily basis. | Wenqin ZHUO Zhina JIANG | 2020 | Journal of Meteorological Research2020，34，6： | 1 |
| 12 | Effects of quenching rate on the microstructure of a rapidly solidified Zn-5wt%Al alloy显示文摘 | Zhang Lin Wu Youshi Bian Xiufang Xing Zhina | 1999 | Journal of Materials Science Letters1999，，23： | 1 |
| 13 | Hyperparameter Optimization for Capsule Network Based Modified Hybrid Rice Optimization Algorithm显示文摘Hyperparameters play a vital impact in the performance of most machine learning algorithms.It is a challenge for traditional methods to con-figure hyperparameters of the capsule network to obtain high-performance manually.Some swarm intelligence or evolutionary computation algorithms have been effectively employed to seek optimal hyperparameters as a com-binatorial optimization problem.However,these algorithms are prone to get trapped in the local optimal solution as random search strategies are adopted.The inspiration for the hybrid rice optimization(HRO)algorithm is from the breeding technology of three-line hybrid rice in China,which has the advantages of easy implementation,less parameters and fast convergence.In the paper,genetic search is combined with the hybrid rice optimization algorithm(GHRO)and employed to obtain the optimal hyperparameter of the capsule network automatically,that is,a probability search technique and a hybridization strategy belong with the primary HRO.Thirteen benchmark functions are used to evaluate the performance of GHRO.Furthermore,the MNIST,Chest X-Ray(pneumonia),and Chest X-Ray(COVID-19&pneumonia)datasets are also utilized to evaluate the capsule network learnt by GHRO.The experimental results show that GHRO is an effective method for optimizing the hyperparameters of the capsule network,which is able to boost the performance of the capsule network on image classification. | Zhiwei Ye Ziqian Fang Zhina Song Haigang Sui Chunyan Yan Wen Zhou Mingwei Wang | 2023 | Intelligent Automation & Soft Computing2023，37，8： | 0 |
| 14 | Influence of Arctic Sea-ice Concentration on Extended-range Forecasting of Cold Events in East Asia显示文摘Utilizing the Community Atmosphere Model,version 4,the influence of Arctic sea-ice concentration(SIC)on the extended-range prediction of three simulated cold events(CEs)in East Asia is investigated.Numerical results show that the Arctic SIC is crucial for the extended-range prediction of CEs in East Asia.The conditional nonlinear optimal perturbation approach is adopted to identify the optimal Arctic SIC perturbations with the largest influence on CE prediction on the extended-range time scale.It shows that the optimal SIC perturbations are more inclined to weaken the CEs and cause large prediction errors in the fourth pentad,as compared with random SIC perturbations under the same constraint.Further diagnosis reveals that the optimal SIC perturbations first modulate the local temperature through the diabatic process,and then influence the remote temperature by horizontal advection and vertical convection terms.Consequently,the optimal SIC perturbations trigger a warming center in East Asia through the propagation of Rossby wave trains,leading to the largest prediction uncertainty of the CEs in the fourth pentad.These results may provide scientific support for targeted observation of Arctic SIC to improve the extended-range CE prediction skill. | Chunxiang LI Guokun DAI Mu MU Zhe HAN Xueying MA Zhina JIANG Jiayu ZHENG Mengbin ZHU | 2023 | Advances in Atmospheric Sciences2023，40，12： | 0 |
| 15 | The Influence of Arctic Sea Ice Concentration Perturbations on Subseasonal Predictions of North Atlantic Oscillation Events显示文摘The influence of Arctic sea ice concentration (SIC) on the subseasonal prediction of the North Atlantic Oscillation (NAO) event is investigated by utilizing the Community Atmospheric Model version 4. The optimal Arctic SIC perturbations which exert the greatest influence on the onset of an NAO event from a lead of three pentads (15 days) are obtained with a conditional nonlinear optimal perturbation approach. Numerical results show that there are two types of optimal Arctic SIC perturbations for each NAO event, with one weakening event (marked as type-1) and another strengthening event (marked as type-2). For positive NAO events, type-1 optimal SIC perturbations mainly show positive SIC anomalies in the Greenland, Barents, and Okhotsk Seas, while type-2 perturbations mainly feature negative SIC anomalies in these regions. For negative NAO events, the optimal SIC perturbations have almost opposite patterns to those in positive events, although there are some differences among these SIC perturbations due to different atmospheric initial conditions. Further diagnosis reveals that the optimal Arctic SIC perturbations first modify the surface turbulent heat flux and the temperature in the lower troposphere via diabatic processes. Afterward, the temperature in the low troposphere is mainly affected by dynamic advection. Finally, potential vorticity advection plays a crucial role in the 500-hPa geopotential height prediction in the northern North Atlantic sector during pentad 4, which influences NAO event prediction. These results highlight the importance of Arctic SIC on NAO event prediction and the spatial characteristics of the SIC perturbations may provide scientific support for target observations of SIC in improving NAO subseasonal predictions. | Guokun DAI Mu MU Zhe HAN Chunxiang LI Zhina JIANG Mengbin ZHU Xueying MA | 2023 | Advances in Atmospheric Sciences2023，40，12： | 0 |
| 16 | Evaluation of the Forecast Performance for North Atlantic Oscillation Onset显示文摘By utilizing operational forecast products from TIGGE(The International Grand Global Ensemble) during 2006 to 2015,the forecasting performances of the European Centre for Medium-Range Weather Forecasts(ECMWF), National Centers for Environmental Prediction(NCEP), Japan Meteorology Agency(JMA) and China Meteorological Administration(CMA) for the onset of North Atlantic Oscillation(NAO) events are assessed against daily NCEP–NCAR reanalysis data. Twenty-two positive NAO(NAO+) and nine negative NAO(NAO-) events are identified during this time period. For these NAO events,control forecasts, one member of the ensemble that utilizes the currently most proper estimate of the analysis field and the best description of the model physics, are able to predict their onsets three to five days in advance. Moreover, the failure proportion for the prediction of NAO-onset is higher than that for NAO+ onset, which indicates that NAO-onset is harder to forecast. Among these four operational centers, ECMWF has performs best in predicting NAO onset, followed by NCEP,JMA, and then CMA.The forecasting performance of the ensemble mean is also investigated. It is found that, compared with the control forecast, the ensemble mean does not improve the forecasting skill with respect to the onset time of NAO events. Therefore,a confident forecast of NAO onset can only be achieved three to five days in advance. | Guokun DAI Mu MU Zhina JIANG | 2019 | Advances in Atmospheric Sciences2019，36，7： | 0 |
| 17 | Ab initio Study of Mechanism of Cycloaddition Reaction be- tween Germylene Silylene (H2Ge=Si:) and Acetone显示文摘在汗衫 germylene silylene 之间的 cycloaddition 反应的机制(H2GeSi :) 并且丙酮与 CCSD (T)/6-31G 被调查了 *// MP2/6-31G * 方法。从势能侧面,我们能预言反应有二条竞争主导的反应隧道。这反应的现在的规则是[2+2 ] cycloaddition 反应二(在 germylene silylene 结合,丙酮与 Ge 产生四成员的戒指 silylene。因为在有 Ge 的四成员的戒指 silylene 的 Si 原子的不饱和的性质,它能进一步与丙酮反应,导致有 Si 和 Ge 的二度杂环的混合物的产生。同时,有 Ge 的四成员的戒指 silylene 的戒指紧张使它成为 isomerize 到一个扭曲的四成员的戒指产品。 | Lu, Xiuhui Han, Junfeng Li, Yongqing Wang, Zhina | 2011 | Chinese Journal of Chemistry2011，29，9： | 0 |
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