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| 1 | Roles of a sustained activation of NCED3 and the synergistic regulation of ABA biosynthesis and catabolism in ABA signal production in Arabidopsis显示文摘ABA, acting as a stress signal, plays crucial roles in plant resistance to water stress. Because ABA signal production is based on ABA biosynthesis, the regulation of NCED, a key enzyme in the ABA biosynthesis pathway, is normally thought of as the sole factor controlling ABA signal production. Here we demonstrate that ABA catabolism in combination with a synergistic regulation of ABA biosynthesis plays a crucial role in governing ABA signal production. Water stress induced a significant accumulation of ABA, which exhibited different patterns in detached and attached leaves. ABA catabolism followed a temporal trend of exponential decay for both basic and stress ABA, and there was little difference in the catabolic half-lives of basic ABA and stress ABA. Thus, the absolute rate of ABA catabolism, i.e. the amount of ABA catabolized per unit time, increases with increased ABA accumulation. From the dynamic processes of ABA biosynthesis and catabolism, it can be inferred that stress ABA accumulation may be governed by a synergistic regulation of all the steps in the ABA biosynthesis pathway. Moreover, to maintain an elevated level of stress ABA sustained activation of NCED3 should be required. This inference was supported by further findings that the genes encoding major enzymes in the ABA biosynthesis pathway, e.g. NCED3, AAO3 and ABA3 were all activated by water stress, and with ABA accumulation progressing, the expressions of NCED3, AAO3 and ABA3 remained activated. Data on ABA catabolism and gene expression jointly indicate that ABA signal production is controlled by a sustained activation of NCED3 and the synergistic regulation of ABA biosynthesis and catabolism. | REN HuiBo FAN YiJian GAO ZhiHui WEI KaiFa LI GuiFen LIU Jing CHEN Lin LI BingBing HU JianFang JIA WenSuo | 2007 | Chinese Science Bulletin2007，52，4： | 12 |
| 2 | Contribution of ultrasonic surface rolling process to the fatigue properties of TB8 alloy with body-centered cubic structure显示文摘The effect of ultrasonic surface rolling process(USRP) as a severe plastic deformation technology was investigated on the evolution of microstructure, residual stress and surface morphology of TB8 alloys with body-centered cubic structure. Stress-controlled rotating-bending fatigue tests indicated increased fatigue strength in USRP samples prepared using different number of passes compared to the base material, which was attributed to the presence of gradient structure surface layers. Five subsequent USRP passes resulted in the highest fatigue strength, due to the optimal surface properties including higher extent of grain refinement, larger compressive residual stresses, 'smoother' surface morphology and increased micro-hardness. However, the effect of USRP technology on improving fatigue strength of TB8 alloy was not significant in comparison with that of other titanium alloys(for example, Ti6 Al4 V), which was attributed to the notable surface residual stresses relaxation revealed from measurements on postfatigued USRP samples. Electron backscatter diffraction analysis confirmed that fatigue crack initiation occurred in the larger grains on the surface with high Schmid factor. Small cracks were found to propagate into the core material in a mixed transgranular and intergranular mode. Further analysis indicated that grain growth existed in post-fatigued USRP-treated TB8 samples and that the average geometrically necessary dislocations value reduced after fatigue loading. | Dan Liu Daoxin Liu Mario Guagliano Xingchen Xu Kaifa Fan Sara Bagherifard | 2021 | Journal of Materials Science & Technology2021，，2： | 5 |
| 3 | Global dynamics of a viral infection model with full logistic terms and antivirus treatments显示文摘 | Lijuan Song Cui Ma Qiang Li Aijun Fan Kaifa Wang | 2017 | International Journal of Biomathematics2017，10，1： | 1 |
| 4 | Global prop- erties of an improved hepatitis B virus model 显示文摘 | Wang Kaifa Fan Aijun Torres Angela | 2010 | Nonlinear Analysis: RWA2010，11，： | 1 |
| 5 | A viral infection model with immune circadian rhythms显示文摘 | Fan Aijun Wang Kaifa | 2010 | Applied Mathematics and Computation2010，215，9： | 1 |
| 6 | Assessing the mechanism of citywide test-trace-isolate Zero-COVID policy and exit strategy of COVID-19 pandemic显示文摘Background:Countries that aimed for eliminating the cases of COVID-19 with test-trace-isolate policy are found to have lower infections,deaths,and better economic performance,compared with those that opted for other mitigation strategies.However,the continuous evolution of new strains has raised the question of whether COVID-19 eradication is still possible given the limited public health response capacity and fatigue of the epidemic.We aim to investigate the mechanism of the Zero-COVID policy on outbreak containment,and to explore the possibility of eradication of Omicron transmission using the citywide test-trace-isolate(CTTI)strategy.Methods:We develop a compartmental model incorporating the CTTI Zero-COVID policy to understand how it contributes to the SARS-CoV-2 elimination.We employ our model to mimic the Delta outbreak in Fujian Province,China,from September 10 to October 9,2021,and the Omicron outbreak in Jilin Province,China for the period from March 1 to April 1,2022.Projections and sensitivity analyses were conducted using dynamical system and Latin Hypercube Sampling/Partial Rank Correlation Coefcient(PRCC).Results:Calibration results of the model estimate the Fujian Delta outbreak can end in 30(95%confdence interval CI:28–33)days,after 10(95%CI:9–11)rounds of citywide testing.The emerging Jilin Omicron outbreak may achieve zero COVID cases in 50(95%CI:41–57)days if supported with sufcient public health resources and population compliance,which shows the efectiveness of the CTTI Zero-COVID policy.Conclusions:The CTTI policy shows the capacity for the eradication of the Delta outbreaks and also the Omicron outbreaks.Nonetheless,the implementation of radical CTTI is challenging,which requires routine monitoring for early detection,adequate testing capacity,efcient contact tracing,and high isolation compliance,which constrain its benefts in regions with limited resources.Moreover,these challenges become even more acute in the face of more contagious variants with a high proportion of asymptomatic cases.Hence,in regions where CTTI is not possible,personal protection,public health control measures,and vaccination are indispensable for mitigating and exiting the COVID-19 pandemic. | Pei Yuan Yi Tan Liu Yang Elena Arufo Nicholas H.Ogden Guojing Yang Haixia Lu Zhigui Lin Weichuan Lin Wenjun Ma Meng Fan Kaifa Wang Jianhe Shen Tianmu Chen Huaiping Zhu | 2022 | Infectious Diseases of Poverty2022，11，5： | 0 |
| 7 | Eliminating carbon contamination with improved one-step electrochemical preparation of refractory high-entropy alloy TiZrHfNbTa显示文摘Creating refractory high-entropy alloys(RHEAs)effectively without impurities is a momentous challenge.Conventional methods for the preparation of RHEAs have exacting requirements for raw material purity and energy consumption.Molten salt electrolytic oxides are applied to the preparation of HEAs by virtue of their low cost and high efficiency.However,the use of graphite anodes in electrolysis will result in the carbon contamination of the products due to the deposition of CO_(3)^(2−)at the cathode.Increasing the reaction temperature accelerates the deoxidation of the oxide,thus reducing the amount of carbide but not eliminating it.Switching HfH_(2)instead of HfO_(2)and using Nb_(2)O_(5)to shield the precursor can effectively remove carbon contamination.However,this leads to a complicated preparation process and energy waste.Herein,we use the solid oxygen ion-conducting membrane(SOM)containing graphite and Sn(named as SOM@C/Sn)anode to separate the carbon from the molten salt and prevent the circulation of CO_(3)^(2−).The pure single-phase TiZrHfNbTa RHEA can be produced in only one-step with the SOM@C/Sn anode,which completely solves the problem of carbon contamination in the molten salt electrolysis preparation of HEAs.This work provides a feasible solution for the preparation of novel complex alloys such as carbon-free RHEAs in a low-cost short process. | Peng Li Jinhang Fan Kaifa Du Peilin Wang Ao Liu Huayi Yin Dihua Wang | 2023 | Journal of Materials Science & Technology2023，，32： | 0 |
| 8 | Deformation mechanism and in-situ TEM compression behavior of TB8βtitanium alloy with gradient structure显示文摘Severe plastic deformation is known to induce grain refinement and gradient structure on metals’surfaces and improve their mechanical properties.However,the fundamental mechanisms behind the grain refinement and micromechanical properties of materials subjected to severe plastic deformation are not still well studied.Here,ultrasonic surface rolling process(USRP)was used to create a gradient microstructure,consisting of amorphous,equiaxed nano-grained,nano-laminated,ultrafine laminated and ultrafine grained structure on the surface of TB8βtitanium alloy.High energy and strain drove element co-segregation on sample surface leading to an amorphous structure during USRP processing.In situ transmission electron microscope compression tests were performed in the submicron sized pillar extracted from gradient structure and coarse grain,in order to reveal the micromechanics behavior of different grain morphologies.The ultrafine grained layer exhibited the lowest yield stress in comparison with single crystal and amorphous-nanocrystalline layers;the ultrafine grained layer and single crystal had an excellent strain hardening rate.The discrepancy among the grain sizes and activated dislocation sources led to the above mentioned different properties.Dislocation activities were observed in both compression test and microstructure evolution of USRP-treated TB8 alloy.An evolution of dislocation tangles and dislocation walls into low angle grain boundaries and subsequent high angle grain boundaries caused the grain refinement,where twinning could not be found and no phase transformation occurred. | Dan Liu Daoxin Liu Junfeng Cui Xingchen Xu Kaifa Fan Amin Ma Yuting He Sara Bagherifard | 2021 | Journal of Materials Science & Technology2021，，25： | 0 |
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