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广东河源市2024年4月暴雨洪水成因分析

中国防汛抗旱 2024年第10期34卷 96-101页

作者：陈宇曾丹丹林浩广东省水文局惠州水文分局惠州516000 河源市气象局河源517000 河源市应急管理局河源517000

2024年4月,广东河源市出现持续强降水过程,具有强对流猛烈、累计雨量大、超警戒河流多、极端性显著、致灾风险高等特点。多项气象水文特征值均突破4月同期历史极值,东江近年来首次发生编号洪水。面对严峻形势,河源市各级部门通力合作,... 详细信息

2024年4月,广东河源市出现持续强降水过程,具有强对流猛烈、累计雨量大、超警戒河流多、极端性显著、致灾风险高等特点。多项气象水文特征值均突破4月同期历史极值,东江近年来首次发生编号洪水。面对严峻形势,河源市各级部门通力合作,成功防御强降雨,实现不死人、少损失目标。对河源市2024年4月暴雨洪水进行总结并剖析成因,为今后河源市水灾害防御提供参考。

关键词：暴雨洪水气候成因水灾害防御广东河源市

合成生物学策略发现新型核糖体肽Xenopeptide

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科学通报 2024年第10期69卷 1361-1372页

作者：莫天录曾丹丹马溯泽贾一飞韩沅均丁伟张琪上海理工大学健康科学与工程学院上海200093 复旦大学化学系上海200433 上海交通大学生命科学技术学院微生物代谢国家重点实验室上海200240

S-腺苷甲硫氨酸自由基(rSAM)酶家族是目前已知的最大酶超家族之一,由22000多个成员组成.这些酶在大自然中广泛存在,被认为是地球上最早的生物催化剂之一.随着大量的微生物基因组信息被解析,分析显示,微生物中大量核糖体肽类天然产物的... 详细信息

S-腺苷甲硫氨酸自由基(rSAM)酶家族是目前已知的最大酶超家族之一,由22000多个成员组成.这些酶在大自然中广泛存在,被认为是地球上最早的生物催化剂之一.随着大量的微生物基因组信息被解析,分析显示,微生物中大量核糖体肽类天然产物的生物合成基因簇中含有rSAM酶;其中Xenorhabdus、Yersinia和Erwinia三个属的基因组中均含有一个高度保守的rSAM酶负责其相邻核糖体肽的前体修饰,此类前体肽和rSAM酶构成的XYE系统所合成的化合物鲜有报道.本研究合成一个来源于Xenorhabdus ***12.1的XYE系统的前体肽和rSAM修饰酶基因,在大肠杆菌中进行共表达,得到新型核糖体肽Xenopeptide,通过结构解析发现,rSAM酶XenB负责分子内2个碳碳键的形成.本研究为微生物中此类化合物的深度挖掘和合成生物学改造提供了理论支撑.

关键词： S-腺苷甲硫氨酸自由基酶核糖体肽翻译后修饰合成生物学

珠三角城市群建设用地开发强度时空格局演化及影响因素分析

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时空信息学报 2024年第2期31卷 248-258页

作者：董泽楷王海军彭小桃孙端谭紫玲王权曾丹旦武汉大学资源与环境科学学院武汉430079 自然资源部华南热带亚热带自然资源监测重点实验室广州510663 广东省国土资源测绘院广州510663 贵州财经大学公共管理学院贵阳550025 武汉东湖学院经济学院武汉430212

建设用地开发强度作为区域城市现代化水平的综合反映及衡量指标,进行其时空变化的测度及影响因素的分析对国土空间合理优化管控具有重要作用;虽然相关研究日益丰富完善,但研究尺度多以城市为单位,方法层面多利用地理加权回归模型进行要... 详细信息

建设用地开发强度作为区域城市现代化水平的综合反映及衡量指标,进行其时空变化的测度及影响因素的分析对国土空间合理优化管控具有重要作用;虽然相关研究日益丰富完善,但研究尺度多以城市为单位,方法层面多利用地理加权回归模型进行要素空间异质性的探究。本文以珠三角城市群为研究区域,构建建设用地开发强度模型体系,计算2010~2020年珠三角各县(区)建设用地开发强度指数,通过空间自相关分析、普通最小二乘法与多尺度地理加权回归对开发强度空间特征以及各影响因素的时空格局演化进行探究。结果表明:①2010~2020年珠三角城市群建设用地开发强度总体呈增长态势,空间差异显著;高强度区主要集中于广州市、深圳市等中心地区,低强度区主要集中于肇庆市、江门市等周围地区;②珠三角建设用地开发强度正向空间集聚效益显著,冷热点空间分布格局与对应开发强度数值空间分布格局基本一致;③固定资产投资、地方财政支出及社会消费品零售总额是影响珠三角建设用地开发强度时空异质性的主导因素,三者均为社会经济影响要素,在各县区中影响程度存在差异性与不稳定性。

关键词：建设用地开发强度时空格局影响因素多尺度地理加权回归珠三角城市群

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Plasmon coupling-driven enhanced high-order multiphoton excited fluorescent performance of metal-organic frameworks

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Nano Research 2024年第7期17卷 6502-6508页

作者： Tong Meng Bo Li Linlin zeng Xianshun Sun Yupeng Tian Hongping Zhou Meng Zhou dandan Li Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid MaterialsMinistry of EducationAnhui UniversityHefei 230601China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Accessing high-order multiphoton excited fluorescence(H-MPEF)materials is challenging yet and needs complicated synthesis *** this study,we successfully assembled plasmonic Au nanorods(Au NRs)with multiphoton responsive metalorganic frameworks(MOFs),resulting in a significant several-fold enhancement of *** extent of multiphoton enhancement was found to be strongly dependent on the degree of overlap between the multiphoton excitation wavelength of MOFs and the localized surface plasmon resonance absorbance of Au NRs,indicating the importance of plasmon-induced resonance energy ***,plasmon-induced hot electron transfer played a vital role in enhanced multiphoton activity as ***,the optimum H-MPEF enhancement occurs at the second near-infrared(NIR-II)region,which provides a promising platform for fluorescent *** findings provide a feasible and practical method to fabricate optimized H-MPEF materials for biological imaging using tissue-penetrating NIR-II light.

关键词： metal-organic framework(MOF) plasmon resonance multiphoton activity fluorescence imaging

Fusarium-produced vitamin B6 promotes the evasion of soybean resistance by Phytophthora sojae

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植物学报:英文版 2023年第9期65卷 2204-2217页

作者： Shuchen Wang Xiaoyi Zhang Zhichao Zhang Yun Chen Qing Tian dandan zeng Miao Xu Yan Wang Suomeng Dong Zhonghua Ma Yuanchao Wang Xiaobo Zheng Wenwu Ye Department of Plant Pathology Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Plant Immunity Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Soybean Disease and Pest Control(Ministry of Agriculture and Rural Affairs) Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of BiotechnologyZhejiang UniversityHangzhou 310058China

Plants can be infected by multiple pathogens concurrently in natural systems. However,pathogen–pathogen interactions have rarely been studied. In addition to the oomycete Phytophthora sojae, fungi such as Fusarium spp. also cause soybean root rot. In a 3-year field investigation, we discovered that P. sojae and Fusarium spp. frequently coexisted in diseased soybean roots. Out of 336 P. sojae–soybean–Fusarium combinations,more than 80% aggravated disease. Different Fusarium species all enhanced P. sojae infection when co-inoculated on soybean. Treatment with Fusarium secreted non-proteinaceous metabolites had an effect equal to the direct pathogen coinoculation. By screening a Fusarium graminearum mutant library, we identified Fusarium promoting factor of Phytophthora sojae infection 1(Fpp1),encoding a zinc alcohol dehydrogenase. Fpp1 is functionally conserved in Fusarium and contributes to metabolite-mediated infection promotion, in which vitamin B6(VB6) produced by Fusarium is key. Transcriptional and functional analyses revealed that Fpp1 regulates two VB6 metabolism genes, and VB6 suppresses expression of soybean disease resistance-related genes. These results reveal that co-infection with Fusarium promotes loss of P. sojae resistance in soybean, information that will inform the sustainable use of diseaseresistant crop varieties and provide new strategies to control soybean root rot.

关键词： fungal metabolites pathogen–host interaction Phytophthora sojae soybean root rot vitamin B6

Wide spectrum and rapid calculation model for atmospheric radiative transfer in limb remote sensing

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遥感学报 2015年第1期19卷 93-99页

作者： GUO Jing YANG Chunping zeng dandan YE Yutang RAO Changhui School of Opto-electronic Information University of Electronic Science and Technology of China Institute of Optics and Electronics Chinese Academy of Sciences

We proposed a wide spectrum and rapid calculation model FALTRAN( Fast Atmospheric Limb TRANsmission),to solve the problems of current radiative transfer model in limb remote sensing. In FALTRAN:( 1) Band model algorithm was employed and the molecular spectroscopy database was based on HITRAN2008.( 2) Limb radiative transfer equation consists of scattering and thermal radiation was established,and according to the limb geometry characteristic,a Hemisphere Radiation Adding( HRA) approach based on finite difference method was proposed to solve it. We investigated the atmospheric limb radiations under typical atmospheric modes in several commonly used remote sensing bands. Moreover,radiation contribution by two hemispheres was quantitative analyzed as well. Validation results show that the relative differences between FALTRAN and Combining Differential-Integral( CDI) model are within 2%,and calculation results by FALTRAN have good agreement with Michelson Interferometer for Passive Atmospheric Sounding( MIPAS) measurements. FALTRAN is proven to be reliable in the limb radiative transfer calculation.

关键词： limb remote sensing band model algorithm limb radiative transfer equation Hemisphere Radiation Adding radiance contribution

Low friction under ultrahigh contact pressure enabled by self-assembled fluorinated azobenzene layers

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Friction 2024年第7期12卷 1434-1448页

作者： dandan XUE Zhi XU Linyuan GUO Wendi LUO Liran MA Yu TIAN Ming MA Qingdao zeng Ke DENG Wenjing ZHANG Yichun XIA Shizhu WEN Jianbin LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China National Center for Nanoscience and Technology Beijing 100190China

Extensive efforts have been made to pursue a low-friction state with promising applications in many fields,such as mechanical and biomedical *** which,the load capacity of the low-friction state has been considered to be crucial for industrial ***,we report a low friction under ultrahigh contact pressure by building a novel self-assembled fluorinated azobenzene layer on an atomically smooth highly-oriented pyrolytic graphite(HOPG)*** friction coefficients could be as low as 0.0005 or even lower under a contact pressure of up to 4 *** demonstrates that the low friction under ultrahigh contact pressure is attributed to molecular *** fluorination leads to effective and robust lubrication between the tip and the self-assembled layer and enhances tighter rigidity which can reduce the stress concentration in the substrate,which was verified by density functional theory(DFT)and molecular dynamics(MD)*** work provides a new approach to avoid the failure of ultralow friction coefficient under relatively high contact pressure,which has promising potential application value in the future.

关键词： ultrahigh contact pressure self-assembled layer fluorination robust lubrication

Application Effect of External Diaphragm Pacemaker Combined with Active Respiratory Circulation Technology in Pulmonary Rehabilitation of Perioperative Lung Cancer Patients

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Journal of Cancer Therapy 2024年第4期15卷 190-200页

作者： Linjuan zeng Gaoyang Duan dandan Liu Heping Wu Cancer Prevention and Treatment Center Department of Thoracic Surgery Sun Yat-sen University Guangzhou China

Aim: To explore the application effect of external diaphragm pacemaker combined with active respiratory circulation technology in pulmonary rehabilitation of perioperative lung cancer patients. Methods: A total of 98 lung cancer patients admitted to our hospital from April 2020 to November 2021 were selected as the observation objects, and then divided into a control group and an observation group using the random number table method, with 49 cases in each group. The control group received routine admission guidance and active respiratory circulation training, while the observation group was supplemented with external diaphragm pacemaker on the basis of the control group. The intervention effect was evaluated by blood gas indicators, pulmonary function indicators, diaphragm function indicators, sputum comfort degree, and activity tolerance indicators before and after intervention. Results: Before intervention, there were no significant differences in blood gas analysis indicators, pulmonary function indicators, diaphragm function indicators, sputum comfort degree, and activity tolerance indicators between the two groups (P > 0.05). After intervention, the improvement degree of the above indicators in the observation group was higher than that in the control group (P < 0.05). Conclusions: The application of external diaphragm pacemaker combined with active respiratory circulation technology in pulmonary rehabilitation of perioperative lung cancer patients is significant, which can effectively improve the pulmonary function, blood gas function, and diaphragm function of lung cancer patients after surgery, and improve the activities of daily living and quality of life of patients.

关键词： The Extracorporeal Diaphragm Pacemaker Active Breathing and Circulation Training Lung Cancer Diaphragmatic Mobility Pulmonary Function

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临近空间大气密度时空扰动规律及建模研究

力学学报 2022年第11期54卷 2984-2993页

作者：曾丹丹万田李帅辉中国科学院力学研究所高温气体动力学国家重点实验室北京100190 中国科学院大学工程科学学院北京100049

大气密度是飞行器能源动力设计、飞行控制中的重要输入参数.近年来,多项研究发现,对于临近空间高层大气,常用经验模型如USSA-76, NRLMSISE-00的密度预示值偏大.另外,随着飞行器精细化设计趋势,要求经验模型可预示不同纬度、昼夜和季节... 详细信息

大气密度是飞行器能源动力设计、飞行控制中的重要输入参数.近年来,多项研究发现,对于临近空间高层大气,常用经验模型如USSA-76, NRLMSISE-00的密度预示值偏大.另外,随着飞行器精细化设计趋势,要求经验模型可预示不同纬度、昼夜和季节条件下的密度特性.基于此,本文利用卫星观测数据全面分析了临近空间大气密度随纬度、地方时、日期的变化规律,包括变化模式和变化幅度.纬度、日期引起的变化幅度大于地方时引起的变化幅度.纬度、日期引起的密度变化在不同高度范围表现出不同模式;变化幅度在78 km附近达最大值,在22 km和92 km附近达局部极小值.地方时引起的密度变化随高度递增.根据大气密度的时空变化特性,本文提出了临近空间大气密度的时空扰动模型,该模型能描述临近空间大气密度及其随纬度、地方时、日期的变化规律.与以往经验模型相比,时空扰动模型可更好地描述不同高度下密度的时空变化规律.在相同误差带条件下,本文模型的置信度明显优于NRLMSISE-00.本文建模方法合理,模型结果对临近空间飞行器设计有应用价值.

关键词：临近空间大气密度时空扰动规律卫星观测数据经验模型