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Biogenesis,action and biological functions of an Arabidopsis 5' t RF,5' ts R-Ala

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Science China(Life Sciences) 2022年第5期65卷 1050-1052页

作者： Chunyan Liu bo cao Xiaofeng cao State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing) Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Microbial Metabolism School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200030China Center for Excellence in Molecular Plant Sciences Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Transfer RNAs(tRNAs) are one class of most conserved and abundant RNA species with 76–90 nucleotides(nt) in *** constitute approximately 4%–15% of total cellular RNAs and are well known for translating the codons on... 详细信息

关键词： action translating Toll

Effect of impact deformation on shape recovery behavior in Fe-Mn-Si shape memory alloy under shape memory training process with cyclic thermo-mechanical loading

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Science China(Technological Sciences) 2021年第7期64卷 1389-1400页

作者： SUN Qian cao bo IWAMOTO Takeshi SUO Tao Graduate School of Engineering Hiroshima UniversityHigashi-Hiroshima739-8527Japan Cluster of Excellence livMatS@FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies University of FreiburgFreiburgD-79110Germany Academy of Science and Technology Hiroshima UniversityHigashi-Hiroshima739-8527Japan School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China

In the past studies, it has been discovered that the shape memory effect(SME) in the Fe-Mn-Si shape memory alloy(Fe-SMA)can gradually be enhanced by a pre-process called as shape memory training process under cyclic thermo-mechanical *** the other hand, it has been shown that the SME of Fe-SMA can also be affected by changing the strain rate. Therefore, it is possible to improve the SME by combining the strain rate sensitivity and shape memory training process. However, the improvement of SME caused by the training process under impact condition is still unclear. For the training process under impact condition, it is difficult to interrupt the test at the desired strain level due to many reflections of stress waves, which reload the specimen from the free ends. In this paper, to obtain reliable experimental results of SME after the training process under impact condition, the stress waves after first loading are eliminated by the double momentum-trap structure introduced into the impact tensile testing apparatus based on the split Hopkinson pressure bar method. In order to achieve an optimum design of the structure used in experiments, the finite element simulation of the structure is performed. Then, tensile tests in the training process of Fe-28Mn-6Si-5Cr alloy at different strain rates including the impact level are conducted and temperature change of the specimen is measured during training and heating process. As a result, the improvement of SME in the alloy after the training process under quasi-static and impact loading is compared with that under quasi-static loading through verification processes.

关键词： Fe-Mn-Si shape memory alloy training cyclic thermo-mechanical process split Hopkinson pressure bar momentumtrap impact deformation

Negative auto-regulators trap p53 in their web

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Journal of Molecular Cell Biology 2017年第1期9卷 62-68页

作者： Xiang Zhou bo cao Hua Lu Fudan University Shanghai Cancer Center and the Institutes of Biomedical Sciences Fudan University Shanghai 200032 China Department of Biochemistry & Molecular Biology and Tulane Cancer Center Tulane University School of Medicine New Orleans LA 70112 USA

The transcriptional factor p53 activates the expression of a myriad of target genes involving a complicated signalling network, resulting in various cellular outcomes, such as growth arrest, senescence, apoptosis, and metabolic changes, and leading to con- sequent suppression of tumour growth and progression. Because of the profoundly adverse effect of p53 on growth and prolifer- ation of cancer cells, several feedback mechanisms have been employed by the cells to constrain p53 activity. Two major antagonists MDM2 and MDMX （the long forms） are transcriptionally induced by p53, but in return block p53 activity, forming a negative feedback circuit and rendering chemoresistance of several cancer cells. However, they are not alone, as cancer cells also employ other proteins encoded by p53 target genes to inhibit p53 activity at transcriptional, translational, and posttransla- tional levels. This essay is thus composed to review a recent progress in understanding the mechanisms for how cancer cells hijack the p53 autoregulation by these proteins for their growth advantage and to discuss the clinical implications of these auto- regulatory loops.

关键词： p53 MDM2 NGFR transcription feedback loop chemoresistance

Review of Grid-forming Inverters in Support of Power System Operation

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Chinese Journal of Electrical Engineering 2022年第1期8卷 1-15页

作者： Guanhong Song bo cao Liuchen Chang Emera and NB Power Research Centre for Smart Grid Technologies University of New BrunswickFredericton E3B 5A3Canada

The penetration of distributed energy resources in electrical grids has been steadily increasing in an effort to reduce greenhouse gas ***,as interfaces between distributed energy resources and grids,have become critical assets in modern power *** recent years,the development and application of grid-forming inverters have gained significant traction due to their capability of supporting power grid operations.A comprehensive review of grid-forming inverters is presented for power system applications.A comparison between grid-forming inverters and grid-following inverters is conducted in terms of their functionalities to highlight the potential of grid-forming inverter technologies in support of power system stability and *** addition,advanced control strategies integrated into grid-forming inverters under various operation conditions are presented through reviewing the innovations introduced in recent literature and in industrial *** paper is intended to provide an updated reference regarding grid-forming inverters for power system applications to researchers and practitioners in the field of power electronics.

关键词： Grid-forming inverters grid-forming functions power conversion

Physical activity among Chinese school-aged children:National prevalence estimates from the 2016 Physical Activity and Fitness in China The Youth Study

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Journal of Sport and Health Science 2017年第4期6卷 388-394页

作者： Xiang Fan Zhen-bo cao Department of Physical Education Shanghai Jiao Tong University Shanghai 200240 China Shanghai Research Center for Physical Fitness and Health of Children and Adolescents Shanghai University of Sport Shanghai 200438 China School of Kinesiology Shanghai University of Sport Shanghai 200438 China

Purpose: This study was to present national estimates of participating in moderate-to-vigorous physical activity(MVPA) and adherence to the recommendations of 60 min/day of MVPA among Chinese school-aged children and to assess demographic differences in ***: Cross-sectional analyses of data from the 2016 Physical Activity and Fitness in China—The Youth Study. Participants were 90,712 primary, junior middle, and junior high school children(boy: 47%; girl: 53%), recruited from 1204 rural and urban schools across 32 administrative provinces and regions in the Mainland of China. Main outcomes were(a) average MVPA minutes per day in the previous 7 days by self-reports and(b) percentage meeting MVPA ***: Average MVPA time was 45.4 min/day, with boys having more MVPA(47.2 min/day) than girls(43.7 min/day) overall and across the 3 school grade categories. About 30% of participants met MVPA recommendations, with a higher percentage of boys(32%) than girls(28%) overall and across the 3 grades categories. Urban school children outperformed rural children in terms of MVPA time. Overall, boys were more likely to meet MVPA recommendations(adjusted odds ratio(a OR) = 1.19, 95% confidence interval(CI): 1.16–1.22) compared with girls; children in higher grades(junior middle(a OR = 0.92, 95%CI: 0.87–0.98) and junior high(a OR = 0.59, 95%CI: 0.53–0.66)) were less likely to meet recommendations compared with primary school children. The odds of meeting recommendations did not differ between urban and rural children(p = 0.07),but urban boys were found to be more likely to meet recommendations compared with rural boys(a OR = 1.14, 95%CI: 1.06–1.19).Conclusion: Overall, the average MVPA minutes per day among Chinese school-aged children is low, and less than one-third of them meet MVPA recommendations. These results were most evident among junior middle and junior high school children and those living rural areas.

关键词： Children and adolescents Exercise Moderate-to-vigorous physical activity Sedentary behavior

Single-phase Grid-connected PV System with Golden Section Search-based MPPT Algorithm

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Chinese Journal of Electrical Engineering 2021年第4期7卷 25-36页

作者： Shuang Xu Riming Shao bo cao Liuchen Chang School of Electrical and Control Engineering North China University of TechnologyBeijing 100144China R&D Department Alpha Technologies Inc.Bellingham 98226USA Emera and NB Power Research Centre for Smart Grid Technologies University of New BrunswickFredericton E3B5A3Canada

Maximum power point tracking(MPPT)is a technique employed for with variable-power sources,such as solar,wind,and ocean,to maximize energy extraction under all *** commonly used perturb and observe(P&O)and incremental conductance(INC)methods have advantages such as ease of implementation,but they also have the challenge of selecting the most optimized perturbation step or increment size while considering the trade-off between convergence time and *** address these issues,an MPPT solution for grid-connected photovoltaic(PV)systems is proposed that combines the golden section search(GSS),P&O,and INC methods to simultaneously achieve faster convergence and smaller oscillation,converging to the MPP by repeatedly narrowing the width of the interval at the rate of the golden *** proposed MPPT technique was applied to a PV system consisting of a PV array,boost chopper,and *** and experimental results verify the feasibility and effectiveness of the proposed MPPT technique,by which the system is able to locate the MPP in 36 ms and regain a drifting MPP in approximately 30 ms under transient *** overall MPPT efficiency is 98.99%.

关键词： Grid-connected system maximum power point tracking(MPPT) photovoltaic(PV)system single-phase inverter

Amending Research on the Expression of the Contact Force of the Spindle Barrel Finishing Based on EDEM Simulation

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 105-117页

作者： Na Wang Shengqiang Yang Tingting Zhao bo cao Chengwei Wang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024China Shanxi Key Laboratory of Precision Machining Taiyuan University of TechnologyTaiyuan030024China

The spindle barrel finishing is commonly used to improve the surface integrity of the important parts of the high-end equipment while it is difficult to provide enough test artifacts for the traditional trial and error experiment to obtain the desirable processing *** EDEM simulation of the spindle barrel finishing can provide effective help for the process design,however,the difference between the simulation and experiment is closely related to the selection of the contact model during *** this paper,simulations and experiments are conducted based on the identical apparatus and conditions to facilitate the comparison and validation between each *** on the Hertz contact theory,the effect of the material properties of contact objects and the relative position of the workpiece on the contact force is *** expression of the correlation coefficient of the contact model is *** the formula for calculating the contact force between the barrel finishing abrasive and the workpiece that includes influence coefficient of the material properties and the relative positions is ***,the contact force calculation formula is verified by changing the rotating *** result shows that the material correction coefficient ranges from 1.41 to 2.38,which is inversely related to the equivalent modulus *** position correction coefficient ranges from 2.0 to *** relative error value between the calculation result and the experimental test result is from 0.58%to 14.07%.This research lay a theoretical foundation for the correction theory of the core elements of the spindle barrel finishing process.

关键词： Spindle barrel finishing processing EDEM simulation Hertz-Mindlin(no slip)contact model Average contact force Modified coefficient

New insights into p53 functions through its target microRNAs

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Journal of Molecular Cell Biology 2014年第3期8卷 206-213页

作者： Jun-Ming Liao bo cao XiangZhou Hua Lu Department of Biochemistry & Molecular Biology and Tutane Cancer Center Tulane University School of Medicine New Orleans LA 70112 USA

The tumor suppressor p53 pathway, whose alterations are highly associated with all types of human cancers, plays an essential role in preventingtumor development and progression mostly through its downstream target genes. Over the last decade, a growing list of p53 microRNA （miRNA） targets has been identified as additional downstream players of this pathway. Further studies ofthese miRNAs have revealed their more complicated regulations and functions in executing and/or regulating p53 activity. Here, we review the p53 miRNA targets identified thus far, and discuss how they fine-tune p53 stress responses, mediate the crosstalk between p53 and other signaling pathways, and expand the role of p53 in other human diseases in addition to cancers.

关键词： miRNA p53 tumorigenesis cancer

Status quo and future prospects of artificial neural network from the perspective of gastroenterologists

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World Journal of Gastroenterology 2021年第21期27卷 2681-2709页

作者： bo cao Ke-Cheng Zhang bo Wei Lin Chen Department of General Surgery&Institute of General Surgery Chinese People’s Liberation Army General HospitalBeijing 100853China

Artificial neural networks(ANNs)are one of the primary types of artificial intelligence and have been rapidly developed and used in many *** recent years,there has been a sharp increase in research concerning ANNs in gastrointestinal(GI)*** state-of-the-art technique exhibits excellent performance in diagnosis,prognostic prediction,and *** between ANNs and GI experts suggest that efficiency and accuracy might be compatible in virtue of technique ***,the shortcomings of ANNs are not negligible and may induce alterations in many aspects of medical *** this review,we introduce basic knowledge about ANNs and summarize the current achievements of ANNs in GI diseases from the perspective of *** limitations and future directions are also proposed to optimize ANN’s clinical *** consideration of barriers to interdisciplinary knowledge,sophisticated concepts are discussed using plain words and metaphors to make this review more easily understood by medical practitioners and the general public.

关键词： Artificial neural network Gastrointestinal disease Diagnosis Treatment Prognosis Endoscopy