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Science China(Life Sciences) 2019年第12期62卷 1638-1654页

作者： Hanye Guan Yue Li Jiazhen zheng ning liu Jihui Zhang Huarong Tan State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

Staurosporine, belonging to indolocarbazole compounds, is regarded as an excellent lead compound for synthesizing antitumor agents as a potent inhibitor against various protein kinases. In this study, two separate clusters(cluster A and cluster B),corresponding to biosyntheses of K-252 c(staurosporine aglycone) and sugar moiety, were identified in Streptomyces fradiae CGMCC 4.576 and heterologously expressed in Streptomyces coelicolor M1146 separately or together. Sta R, a cluster-situated LAL family regulator, activates staurosporine biosynthesis by binding to the promoter regions of sta O-sta C and sta G-sta N. The conserved sequences GGGGG and GCGCG were found through gradually truncating promoters of sta O and sta G, and further determined by mutational experiments. Overexpression of sta R with the supplementation of 0.01 g L^–1 Fe SO4 increased staurosporine production to 5.2-fold compared with that of the parental strain Streptomyces fradiae CGMCC 4.576 in GYM medium. Our results provided an approach for improvement of staurosporine production mediated by a positive regulator and established the basis for dissecting the regulatory mechanisms of other indolocarbazole compounds with clinical application value.

关键词： transcriptional regulation lead compound antibiotics antitumor gene cluster

Efficacy of Lubeikangru formulation in mice with hyperplasia of the mammary glands induced by estrogen and progesterone

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Journal of Traditional Chinese Medicine 2019年第2期39卷 174-180页

作者： Sun Li Guo Donghui liu Qian Xue Yanan Jiang ning zheng Hongxin Department of Basic Medicine Liaoning University of Traditional Chinese Medicine

OBJECTIVE: To evaluate the protective effects of Lubeikangru formula(LF) on hyperplasia of the mammary glands(HMG) induced by estrogen and progesterone in ***: Female mice were divided randomly into five groups: normal, model, tamoxifen(3 mg/kg),Rupixiao(900 mg/kg) and LF(900 mg/kg). All mice except those in the normal group were treated sequentially with estradiol and progesterone to induce HMG. From the tenth day of induction, mice in normal and model groups received distilled water and mice in the other groups were given the corresponding drugs by gavage, once a day, for 30 *** the end of treatment, the mammary glands, ovaries, hypothalamus, and serum was collected for whole-mount and hematoxylin and eosin(HE)staining, enzyme-linked immunosorbent assays(ELISAs), or western ***: Whole-mount and HE staining of mammary glands showed that LF rescued(at least in part) the hyperplasic morphology of the mammary glands, and the number of branch points decreased after LF treatment(P < 0.05). ELISAs revealed that levels of estrogen and progesterone were decreased following LF treatment, whereas levels of gonadotropin-releasing hormone, follicle-stimulating hormone, and luteinizing hormone were increased in serum and tissues. Western blotting confirmed that LF treatment led to a reduction in expression of phosphorylated(p)-Erk, p-p38 and p-c-Jun N-terminal kinase. LF was also confirmed to be safe by acute-toxicity ***: LF can protect the mammary glands of mice from estrogen-and progesterone-induced hyperplasia by adjusting hormone levels and regulating the mitogen-activated protein kinase pathway.

关键词： Hyperplasia Mammary glands,animal Hormones Tamoxifen Mitogen-activated protein kinases Lubeikangru formulation

Computational protein design and structure prediction—the 2024Nobel prize in chemistry

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Science China Chemistry 2025年

作者： Peilong Lu Lei liu School of Life Sciences and Research Center for Industries of the Future Westlake University Tsinghua-Peking Joint Center for Life Sciences Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Center for Synthetic and Systems Biology Department of Chemistry Tsinghua University

The 2024 Nobel prize in chemistry recognizes groundbreaking advancements in protein science, highlighting the power of artificial intelligence (AI) to decipher and design the molecular machinery of life. Half of the prize was awarded to David Baker for the computational design of proteins; the other to Demis Hassabis and John Jumper for their AI-driven predictions of protein structures. This article briefly reviews their achievements, and discusses the opportunities and directions that their work has enabled (Figure1).

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Precipitation scale effect of the TRMM satellite in Tianshan,China

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Journal of Mountain Science 2023年第5期20卷 1349-1368页

作者： ning Shan ZHOU Hong-wu ZHANG zheng-yong BAI Shi-biao liu Lin College of Marine Sciences and Engineering Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationNanjing Normal UniversityNanjing 210000China College of Sciences Shihezi UniversityShihezi 832000China

High-resolution precipitation data is conducive to objectively describe the spatial-temporal variability of regional precipitation,and the study of downscaling techniques and spatial scale effects can provide technical and theoretical support to improve the spatial resolution and accuracy of satellite precipitation *** this study,we used a machine learning algorithm combined with a regression algorithm RF-PLS(Random Forest-Partial Least Squares)to construct a downscaling model to obtain three types of high-resolution TRMM(Tropical Rainfall Measuring Mission)downscaled precipitation data for the years 2000-2017 at 250 m,500 m,and *** scale effects with topographic and geomorphological features in the study area were ***,we described the spatial and temporal variation of precipitation based on the optimal TRMM downscaled precipitation *** results showed that:1)The linear relationships between the TRMM downscaled precipitation data obtained by each of the three downscaled models(PLS,RF,and RF-PLS)and the precipitation at the observation stations were improved compared to the linear relationships between the original TRMM data and the precipitation at the observation *** accuracy of the RF-PLS model was better than the other two models.2)Based on the RF-PLS model,the resolution of the TRMM data was increased to three different scales(250 m,500 m,and 1 km),considering the scale effects with topographic and geomorphological *** precipitation simulation effect with a spatial resolution of 500 m was better than the other two scales.3)The annual precipitation was the highest in the areas with extremely high mountains,followed by the mediumhigh mountain,high mountain,medium mountain,medium-low mountain,plain,low mountain,and basin.

关键词： TRMM data Scale effect Landform Tianshan Mountains

Beyond Performance of Learning Control Subject to Uncertainties and Noise: A Frequency-Domain Approach Applied to Wafer Stages

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 198-214页

作者： Fazhi Song ning Cui Shuaiqi Chen Kai Zhang Yang liu Xinkai Chen Jiubin Tan IEEE the Center of Ultra-precision Optoelectronic Instrument Engineering Harbin Institute of Technology the Key Laboratory of Ultra-Precision Intelligent Instrumentation Ministry of Industry and Information Technology the State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of Technology the Center of Ultraprecision Optoelectronic Instrument Engineering Harbin Institute of Technology the Key Laboratory of UltraPrecision Intelligent Instrumentation Ministry of Industry and Information Technology the Department of Electronic and Information Systems Shibaura Institute of Technology

The increasingly stringent performance requirement in integrated circuit manufacturing, characterized by smaller feature sizes and higher productivity, necessitates the wafer stage executing a extreme motion with the accuracy in terms of nanometers. This demanding requirement witnesses a widespread application of iterative learning control(ILC), given the repetitive nature of wafer scanning. ILC enables substantial performance improvement by using past measurement data in combination with the system model knowledge. However, challenges arise in cases where the data is contaminated by the stochastic noise, or when the system model exhibits significant uncertainties, constraining the achievable performance. In response to this issue, an extended state observer(ESO) based adaptive ILC approach is proposed in the frequency *** being model-based, it utilizes only a rough system model and then compensates for the resulting model uncertainties using an ESO, thereby achieving high robustness against uncertainties with minimal modeling effort. Additionally, an adaptive learning law is developed to mitigate the limited performance in the presence of stochastic noise, yielding high convergence accuracy yet without compromising convergence speed. Simulation and experimental comparisons with existing model-based and data-driven inversion-based ILC validate the effectiveness as well as the superiority of the proposed method.

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Multi-receptive field interaction network for shape from polarization

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Science China(Information Sciences) 2025年第1期68卷 394-395页

作者： Yini PENG Rui liu Zhiyuan ZHANG Zhongyuan WANG Jiayi MA Xin TIAN Electronic Information School Wuhan University Computer Science School Wuhan University Wuhan Institute of Quantum Technology

Shape from polarization (SfP) method can use the polarization information in reflected light to estimate the surface normal of the target,which can further reconstruct the shape of the *** a simple image capture process,it can use low-cost equipment to meet a high precision imaging requirement,which can be used in remote scenes and other applications.

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The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

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Neural Regeneration Research 2025年第5期20卷 1513-1520页

作者： Xueyun Shao Longfei He Yangyang liu Physical Education School Shenzhen UniversityShenzhenGuangdong ProvinceChina Shenzhen Institute of Neuroscience ShenzhenGuangdong ProvinceChina

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67,

关键词： adolescents brain-derived neurotrophic factor children exercise meta-analysis randomized controlled trials

Deep eutectic solvents for separation and purification applications in critical metal metallurgy:Recent advances and perspectives

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 1-19页

作者： Shuo Chen Shengpeng Su Yanfang Huang Bingbing liu Hu Sun Shuzhen Yang Guihong Han School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metals Laboratory Henan ProvinceZhengzhou 450001China

Solvent extraction,a separation and purification technology,is crucial in critical metal *** solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental *** solvents have been recognized as potential alternatives to these harmful organic *** the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low *** this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically ***,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively ***,future opportunities and challenges of DESs were explored in the current research *** conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy.

关键词： deep eutectic solvents preparations properties separation and purification critical metal metallurgy

Cyber-physical-social-thinking space based science and technology framework for the Internet of Things

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Science China(Information Sciences) 2015年第3期58卷 17-35页

作者： ning HuanSheng liu Hong School of Computer and Communication Engineering University of Science and Technology Beijing Engineering Laboratory RUN Technologies Co. Ltd. Beijing

The Internet of Things(Io T)as an emerging network paradigm is bringing the next scientific and technological revolution for ubiquitous things’interactions in cyber-physical-social *** Io T influences the current science and technology system by enabling its relatively stable interrelations for an inevitable architecture *** this paper,we aim to explore an updated science and technology framework for the Io ***,a novel cyber-physical-social-thinking(CPST)space is established by involving an attractive concept of the Internet of Thinking(Io Tk),and a science and technology framework is accordingly proposed referring to both scientific aspect(i.e.,cyber-physical,social,and noetic sciences)and technological aspect(i.e.,fundamental,physical,cyber,and social technologies).According to the perspective of the traditional Chinese culture,we explain the established science and technology framework,in which the"Five Elements"(i.e.,wood,fire,earth,metal,and water)have common properties with the restructured cyber-physical science in the Io ***,we introduce a scenario of smart city to identify the technological aspect in the Io T,and discuss the key enabling technologies,including resource management,energy management,data management,session management,security and privacy,loop control,space-time consistency,nanotechnology,and quantum *** turns out that the established science and technology framework will launch an innovation for academia and industry communities.

关键词： Internet of Things(Io T) cyber-physical-social-thinking science technology discipline

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压电-光催化材料的研究进展

现代化工 2025年第1期45卷 24-28页

作者：张悦刘鹏霄张旭柳李雨洋刘宁中北大学环境与安全工程学院山西太原030051

基于压电光催化技术的发展背景总结了其工作原理;对几种不同的压电光催化材料进行了介绍,并综述了其在环境水处理、气体净化、能源析氢等领域的研究进展;阐明了压电-光催化材料面临的问题并对其未来发展提出了建议,为压电光催化材料的... 详细信息

基于压电光催化技术的发展背景总结了其工作原理;对几种不同的压电光催化材料进行了介绍,并综述了其在环境水处理、气体净化、能源析氢等领域的研究进展;阐明了压电-光催化材料面临的问题并对其未来发展提出了建议,为压电光催化材料的设计和深入研究提供参考。

关键词：压电光催化基本原理环境修复能源析氢