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Construction of daily precipitation series and the observational characteristics of extreme precipitation in Tianjin,China during 1888-2022

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Advances in Climate Change Research 2024年第1期15卷 52-61页

作者： peng SI Qing-Xiang LI Xiao-Yang CHEN Min WANG Chuan-Jun luo Tianjin Meteorological Information Center Tianjin Meteorological BureauTianjin 300074China Research Centerfor Ecology and Environment of Central Asia Chinese Academy of SciencesWulumuqi 830011China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 528478China Key Laboratory of Tropical Amosphere-Ocean System Ministry of EducationZhuhai 528478China Shaoguan Meteorological Service Shaoguan 512028China

Given the difficulties in rescuing and ensuring the quality of long-term climate data,current studies on century-scale climate change are usually limited to annual and monthly data,resulting in the poor detection of extreme climate events and their changes before *** this study,we reconstructed a daily precipitation series for Tianjin from 15 September 1887 to 31 December 2022 on the basis of the most comprehensive daily precipitation records collected from the Tianjin Meteorological Archive,China,and in reference to the precipitation analysis results based on the datasets developed by the Climatic Research Unit Time-Series version 4.06,Global Precipitation Climatology Centre and University of Delaware along with the application of various homogenisation methods for climate *** approach provides a complete and reliable century-long daily precipitation series for the study of regional or local extreme weather and climate *** reconstructed daily dataset reveals that the annual precipitation amount and R95 intensity in Tianjin during 1888-2022 lack significant trends and have values of 0.74±6.99 and-1.84±3.22 mm per decade,*** the annual and seasonal scales,the precipitation amount and R95 intensity,particularly those in autumn,have increased since the latter half of the 20th century relative to those in ***,the increase in precipitation amount and R95 intensity is relatively limited compared with that in atmospheric water vapour content due to surface warming,indicating the highly sensitive response of extreme precipitation events to *** addition,the estimates for the return periods of 5,10,20,50 and 100 years covering 1888-2022,1888-1950 and 1951-2022 depict that the intensity of heavy rain and above magnitude was highest in 1888-1950 and decreased in 1951-2022.

关键词： Over a century-long timescale Daily precipitation series Extreme precipitation Return period

用于新能源发电的新型升降压转换器及其控制策略

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郑州大学学报（工学版） 2024年第2期45卷 97-105页

作者：罗朋陈光浩杨东红郭磊广东海洋大学电子与信息工程学院广东湛江524088

针对新能源发电装置输出电压变化大难以实现储能的问题,提出一种基于PI控制器结合前馈控制的新型单管耦合型升降压转换器,通过调节耦合电感的变比灵活调节电压转换比,同时降低了开关器件电压应力,采用无源钳位电路,起到回收漏感能量和... 详细信息

针对新能源发电装置输出电压变化大难以实现储能的问题,提出一种基于PI控制器结合前馈控制的新型单管耦合型升降压转换器,通过调节耦合电感的变比灵活调节电压转换比,同时降低了开关器件电压应力,采用无源钳位电路,起到回收漏感能量和抑制开关管电压尖峰的作用,与传统升降压转换器相比具有更宽电压转换比,输入电流连续和开关管电压应力小等优势;利用PI控制器结合前馈控制策略实现闭环控制,保证了转换器整个输入电压范围内良好的输入暂态响应。详细分析了转换器的工作原理并推导了转换器稳态特性,将所提转换器与其他单管升降压转换器的各项性能进行比较。推导了转换器的小信号模型,同时利用伯德图验证PI参数设计的正确性,分析了PI控制器结合前馈控制策略的设计过程。最后,搭建了一台额定功率100 W,20~60 V输入、48 V输出的实验样机,通过升压和降压模式下的实验来验证所提转换器的性能,同时验证了PI控制器结合前馈控制策略的可行性,其中升压模式最大效率为97.08%,降压模式最大效率为97.10%。

关键词：耦合电感升降压转换器小信号模型 PI控制器前馈控制

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Wide Stopband Substrate Integrated Waveguide Filter Using Bisection and Trisection Coupling in Multilayer

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Chinese Journal of Electronics 2024年第2期33卷 436-442页

作者： peng CHU Jianguo FENG peng ZHU Lei GUO Long ZHANG Leilei LIU Guoqing luo Ke WU College of Electronic and Optical Engineering Nanjing University of Posts and Telecommunications National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology School of Information and Communication Engineering Dalian University of Technology Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen University College of Electronics and Information Engineering Shenzhen University School of Electronics and Information Hangzhou Dianzi University Poly-Grames Research Center Polytechnique Montreal

This article presents a highly efficient method for substrate-integrated-waveguide（SIW） filters to achieve very wide stopbands. By employing the proposed trisection slots in addition to the bisection slots as the inter-coupling structures, all spurious modes below TE505 of a SIW filter working in the fundamental mode TE101（f0）can be eliminated without requiring additional structure or complex theoretical analysis, without affecting the design of the fundamental passbands, and without degrading the performance of the filters. For verification, two prototype filters are designed, fabricated, and measured with wide stopbands up to 4.15f0 and 4.83f0, respectively. The proposed technique could facilitate the development of high-performance wide-stopband SIW filters for microwave/wireless circuits and systems.

关键词： Microwave measurement Couplings Filters Prototypes Nonhomogeneous media Microwave theory and techniques Microwave circuits

Mutations in the DNA polymerase binding pathway affect the immune microenvironment of patients with small-cell lung cancer and enhance the efficacy of platinum-based chemotherapy

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Cancer Innovation 2023年第6期2卷 500-512页

作者： Anqi Lin Weiming Mou Lingxuan Zhu Tao Yang Chaozheng Zhou Jian Zhang peng luo Department of Oncology Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdongChina The First Clinical Medical School Southern Medical UniversityGuangzhouGuangdongChina Department of Urology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Etiology and Carcinogenesis National Cancer CenterNational Clinical Research Center for CancerCancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Medical Oncology National Cancer CenterNational Clinical Research Center for CancerCancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background:Small-cell lung cancer(SCLC)is characterized by its high malignancy and is associated with a poor *** the early stages of the disease,platinum-based chemotherapy is the recommended first-line treatment and has demonstrated ***,SCLC is prone to recurrence and is generally resistant to chemotherapy in its later ***:Here,we collected samples from SCLC patients who received platinum-based chemotherapy,performed genomic and transcriptomic analyses,and validated our results with publicly available ***:SCLC patients with DNA polymerase binding pathway mutations had an improved prognosis after platinum chemotherapy compared with patients without such *** in the mutant(MT)group had higher infiltration of T cells,B cells,and M1 macrophages compared with patients without DNA polymerase binding pathway ***:DNA polymerase binding pathway mutations can be used as prognostic markers for platinum-based chemotherapy in SCLC.

关键词： chemotherapy resistance platinum prognosis small-cell lung cancer tumor microenvironment

Interface Design Strategy for GNS/AZ91 Composites with Semi-Coherent Structure

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 467-483页

作者： Jing-peng Xiong Yi-Qi Zeng Jin-Long Liu Wei-Cheng Wang Lan luo Yong Liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China School of Physics and Materials Science Nanchang UniversityNanchang 330031China

The interfacial structure plays an important role in the mechanical properties of magnesium matrix composite(MMCs)reinforced with graphene nanosheet(GNS)due to their poor wettability with the Mg *** interface design strategy was proposed to form the semi-coherent interfacial structure with superior bonding *** lattice mismatch and interfacial bonding strength between Mg/rare earth oxide/carbon were utilized as key characteristics to evaluate the interfacial *** oxide(La2O3)was selected as the intermediate candidate due to its low lattice mismatch and high interfacial bonding *** identify the interfacial structure of Mg/La2O3/graphene,first-principles calculations were conducted to calculate the ideal work of separation and electronic structure of the *** demonstrated the presence of strong ionic and covalent interactions at the interface,which theoretically verified the strong interfacial bonding strength among Mg/La2O3/graphene *** experimentally validate the interface strength,MMCs with the interface structure of Mg/La2O3/GNS were *** formation of in-situ La2O3 led to the successful attainment of semi-coherent structures between Mg/La2O3 and La2O3/GNS,resulting in high strength and good ductility of the ***,this work proposes a new approach to interface design in MMCs with an enhancement of mechanical properties.

关键词： Interface design strategy Magnesium matrix composite Graphene nanosheets Semi-coherent interface Mechanical properties

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盐酸乌拉地尔的新合成工艺研究

中国医药工业杂志 2024年第4期55卷 501-505页

作者：王栋蒋海婷罗鹏陆俊王玲李友军金悦江苏润安制药有限公司研发部江苏淮安223299 江苏正大清江制药有限公司研究所江苏淮安223001

以3-[(叔丁氧羰基)氨基]丙酸(2)和1-(2-甲氧基苯基)哌嗪盐酸盐(3)为起始原料,通过活性酯法进行酰胺合成,得[3-[4-(2-甲氧基苯基)哌嗪-1-基]-3-氧代丙基]氨基甲酸叔丁酯(4),再经脱保护得3-[4-(2-甲氧基苯基)哌嗪-1-基]丙胺三盐酸盐(6盐酸... 详细信息

以3-[(叔丁氧羰基)氨基]丙酸(2)和1-(2-甲氧基苯基)哌嗪盐酸盐(3)为起始原料,通过活性酯法进行酰胺合成,得[3-[4-(2-甲氧基苯基)哌嗪-1-基]-3-氧代丙基]氨基甲酸叔丁酯(4),再经脱保护得3-[4-(2-甲氧基苯基)哌嗪-1-基]丙胺三盐酸盐(6盐酸盐),最后与6‑氯‑1,3‑二甲基尿嘧啶-2,4(1H,3H)-二酮(7)缩合得盐酸乌拉地尔(1盐酸盐)。目标产物经HPLC、^(1)H NMR、^(13)C NMR、MS和元素分析确证。总收率达61.2%(以2计),纯度99.95%。改进后的工艺解决了关键中间体6国产化的技术难题,适合工业化生产。

关键词：乌拉地尔 α受体阻滞剂 N,N-羰基二咪唑合成

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Identifiability of intermediate variables on causal paths

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Frontiers of Mathematics in China 2013年第3期8卷 517-539页

作者： Wanlu DENG Zhi GENG peng luo School of Mathematical Sciences Peking University Beijing 100871 China

We discuss the discovery of causal mechanisms and identifiability of intermediate variables on a causal path. Different from variable selection, we try to distinguish intermediate variables on the causal path from other variables. It is also different from ordinary model selection approaches which do not concern the causal relationships and do not contain unobserved variables. We propose an approach for selecting a causal mechanism depicted by a directed acyclic graph （DAG） with an unobserved variable. We consider several causal networks, and discuss their identifiability by observed data. We show that causal mechanisms of linear structural equation models are not identifiable. Furthermore, we present that causal mechanisms of nonlinear models are identifiable, and we demonstrate the identifiability of causal mechanisms of quadratic equation models. Sensitivity analysis is conducted for the identifiability.

关键词： Causal network directed acyclic graph (DAC) identifiability intermediate variable structural equation model

Quantitative proteomic and phosphoproteomic analyses of the hippocampus reveal the involvement of NMDAR1 signaling in repetitive mild traumatic brain injury

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Neural Regeneration Research 2023年第12期18卷 2711-2719页

作者： Zhicheng Tian Zixuan Cao Erwan Yang Juan Li Dan Liao Fei Wang Taozhi Wang Zhuoyuan Zhang Haofuzi Zhang Xiaofan Jiang Xin Li peng luo Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina The Sixth Regiment School of Basic MedicineFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Neurobiology School of Basic MedicineFourth Military Medical UniversityXi’anShaanxi ProvinceChina Medical Experiment Center Shaanxi University of Chinese MedicineXianyangShaanxi ProvinceChina Department of Anesthesiology The Second Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina School of Life Science Northwest UniversityXi’anShaanxi ProvinceChina Department of Anesthesiology Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina

The cumulative damage caused by repetitive mild traumatic brain injury can cause long-term neurodegeneration leading to cognitive *** cognitive impairment is thought to result specifically from damage to the *** this study,we detected cognitive impairment in mice 6 weeks after repetitive mild traumatic brain injury using the novel object recognition test and the Morris water maze *** staining showed that p-tau expression was increased in the hippocampus after repetitive mild traumatic brain *** staining showed a significant decrease in the total density of neuronal dendritic spines in the hippocampus,as well as in the density of mature dendritic *** investigate the specific molecular mechanisms underlying cognitive impairment due to hippocampal damage,we performed proteomic and phosphoproteomic analyses of the hippocampus with and without repetitive mild traumatic brain *** differentially expressed proteins were mainly enriched in inflammation,immunity,and coagulation,suggesting that non-neuronal cells are involved in the pathological changes that occur in the hippocampus in the chronic stage after repetitive mild traumatic brain *** contrast,differentially expressed phosphorylated proteins were mainly enriched in pathways related to neuronal function and structure,which is more consistent with *** identified N-methyl-D-aspartate receptor 1 as a hub molecule involved in the response to repetitive mild traumatic brain injury,and western blotting showed that,while N-methyl-D-aspartate receptor 1 expression was not altered in the hippocampus after repetitive mild traumatic brain injury,its phosphorylation level was significantly increased,which is consistent with the omics *** of GRP78608,an N-methyl-D-aspartate receptor 1 antagonist,to the hippocampus markedly improved repetitive mild traumatic brain injury-induced cognitive *** conclusion,our findings

关键词： cognitive impairment Grin1 hippocampus learning memory N-methyl-D-aspartate N-methyl-D-aspartate receptor 1 phosphoproteomic proteomic repetitive mild traumatic brain injury(rmTBI) secondary injury

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An alternative surgical technique for varicoceles:a preliminary experience of the microsurgical spermatic(distal end)-inferior or superficial epigastric vein anastomosis in symptomatic varicoceles associated with perineal pain

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Asian Journal of Andrology 2022年第6期24卷 624-627页

作者： Zi Wan Hai-Ming Cao Bi-Cheng Yang Yong Gao Li Ding peng luo Guang-Wen Yang Lin Ma Chun-Hua Deng The Andrology Department The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China The Andrology Department The Reproductive Medicine CenterThe Seventh Affiliated HospitalSun Yat-sen UniversityShenzhen 518107China The Reproductive Medicine Center The Key Laboratory for Reproductive Medicine of Guangdong ProvinceThe First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China The Pathology Department The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China The Urology Department Tongren Municipal People's HospitalTongren 554399China The Reproductive Medicine Center The Seventh Affiliated HospitalSun Yat-sen UniversityShenzhen 518107China

Many therapies are effective in treating varicoceles,including dilation of the pampiniform plexus in *** most common method of treatment is *** aimed to assess an alternative technique(microsurgical spermatic[distal end]-superficial or inferior epigastric vein anastomosis)that preserves the normal blood flow pattern for varicocele *** retrospectively analyzed 27 men with varicocele between October 2019 and July *** patients underwent microsurgical spermatic(distal end)-superficial or inferior epigastric vein *** prognosis was reviewed retrospectively with an additional survey conducted 3 months after *** mean±standard deviation of the age was 26.1±7.3 years in patients with microsurgical spermatic(distal end)-superficial or inferior epigastric vein *** maximum diameter of the varicocele vein,perineal pain score,sperm density,and forward movement of sperm improved over 3 months after *** spermatic(distal end)-superficial or inferior epigastric vein anastomosis is a safe and efficient surgical treatment for varicoceles.

关键词： microsurgery pain varicocele vein anastomosis