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2023年营养健康领域发展态势

生命科学 2024年第1期36卷 21-29页

作者：朱成姝阮梅花刘晓马雪晴熊燕张学博中国科学院上海生命科学信息中心中国科学院上海营养与健康研究所上海200031 中国科学院大学北京100049

营养健康一直是各国关注的核心议题。2023年,全球主要国家(地区)出台了多个促进国民营养健康、保障食品安全和完善食品系统的政策规划;聚焦科学合理膳食改善营养健康,利用食品营养干预辅助疾病治疗,以及通过健康生活方式来延缓衰老等重... 详细信息

营养健康一直是各国关注的核心议题。2023年,全球主要国家(地区)出台了多个促进国民营养健康、保障食品安全和完善食品系统的政策规划;聚焦科学合理膳食改善营养健康,利用食品营养干预辅助疾病治疗,以及通过健康生活方式来延缓衰老等重点领域,并建立新的技术创新中心和研究所,启动新的研究项目推动该领域的科技发展。本文从科技布局与政策监管、重点领域进展与趋势、产品研发与产业发展等角度,对该领域在2023年的进展进行系统梳理,并对领域未来的发展趋势进行展望。

关键词：营养健康食品安全营养干预

Theoretical and experimental study on frequency pushing effect of magnetron

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Chinese Physics B 2019年第11期28卷 377-381页

作者： Kang Li Yi Zhang Hua-cheng zhu Ka-Ma Huang Yang Yang School of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Key Laboratory of Wireless Power Transmission of Ministry of Education Chengdu 610064China

The applications of magnetrons are greatly limited because of the poor output spectrum of the free-running ***, one of the best ways to solve this problem is injection locking. However, the injection locking theory which is widely used nowadays is based on the simplified oscillator, which does not include the frequency pushing effect of the magnetron. In this paper, the theory of injection locking magnetrons with frequency pushing effect is systematically *** analysis shows that the locking bandwidth turns larger with the consideration of the pushing parameter(α), and the increase of locking bandwidth is expanded with α increasing. Experimental results show that the locking bandwidth is expanded by 0.3 MHz, 1 MHz, and 1.6 MHz compared with the locking bandwidth from the conventional locking theory under an injection ratio(ρ) of 0.05, 0.075, and 0.1, respectively. This research provides a more accurate prediction of the properties of the injection-locked magnetron.

关键词： magnetron injection locking pushing effect

The Stability of Multi-modal Traffic Network

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Communications in Theoretical Physics 2013年第7期60卷 48-54页

作者： HAN Ling-Hui Sun Hui-Jun zhu cheng-Juan WU Jian-Jun JIA Bin MOE Key Laboratory for Urban Transportation Complex Systems Theory Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China

There is an explicit and implicit assumption in multimodal traffic equilibrium models, that is, if the equilibrium exists, then it will also occur. The assumption is very idealized; in fact, it may be shown that the quite contrary could happen, because in multimodal traffic network, especially in mixed traffic conditions the interaction among traffic modes is asymmetric and the asymmetric interaction may result in the instability of traffic system. In this paper, to study the stability of multimodal traffic system, we respectively present the travel cost function in mixed traffic conditions and in traffic network with dedicated bus lanes. Based on a day-to-day dynamical model, we study the evolution of daily route choice of travelers in multimodal traffic network using 10000 random initial values for different cases. From the results of simulation, it can be concluded that the asymmetric interaction between the cars and buses in mixed traffic conditions can lead the traffic system to instability when traffic demand is larger. We also study the effect of travelers' perception error on the stability of multimodal traffic network. Although the larger perception error can alleviate the effect of interaction between cars and buses and improve the stability of traffic system in mixed traffic conditions, the traffic system also become instable when the traffic demand is larger than a number. For all cases simulated in this study, with the same parameters, traffic system with dedicated bus lane has better stability for traffic demand than that in mixed traffic conditions. We also find that the network with dedicated bus lane has higher portion of travelers by bus than it of mixed traffic network. So it can be concluded that building dedicated bus lane can improve the stability of traffic system and attract more travelers to choose bus reducing the traffic congestion.

关键词： multi-modal traffic network day-to-day dynamical model stability

Archaeological sites distribution and its physical environmental settings between ca 260-2.2 ka BP in Guizhou, Southwest China

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Journal of Geographical Sciences 2014年第3期24卷 526-538页

作者： LI Kaifeng zhu cheng JIANG Fengqing LI Bing WANG Xinhao CAO BO ZHAO Xiaofan School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China Xinjiang Institute of Ecology and Geography CAS Urumqi 830011 China College of Hydrology and Water Resources Hohai University Nanjing 210098 China Guizhou Provincial Institute of Cultural Relics and Archaeology Guiyang 550004 China

This study presents an analysis of the spatial-temporal distribution of 230 ar- chaeological sites in Guizhou Province, Southwest China for three selected time periods from the Paleolithic Age to the Shang-Zhou Dynasties. The relationship between archaeological sites distribution and environmental changes is also discussed based on paleo-environmental proxies of 6480 and δ3C recorded in stalagmites from Southwest China. The results show that： in the Paleolithic Age （260-10 ka BP）, archaeological sites were concentrated in the central, northwestern and southwestern parts of Guizhou, where the high-altitudinal karst landforms with many natural caves suitable for human habitation are developed. In the Neo- lithic Age （10-3.6 ka BP）, most of human settlements were concentrated in the central, northwestern and southwestern parts, while, a fewer sites were found on river terraces in the southern and eastern parts, and the intermontane basins in the central and western Guizhou. During the Shang-Zhou Dynasties （3.6-2.2 ka BP）, the sites were mainly distributed in the intermontane basins and on river terraces, which were suitable for primitive aerial farming. The analysis of paleo-environmental proxies of 6180 and δ3C since 260 ka BP suggested that climate fluctuations had little imPact on human settlements in this study area. The distinct physical environment, especially the spatial patterns of karst landforms and arable land played an important role in the archaeological sites distribution of Guizhou.

关键词： Guizhou Province archaeological sites temporal-spatial distribution the Paleolithic Age to theShang-Zhon Dynasties physical environment

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飞机燃油箱参数化布局及结构设计

制造业自动化 2024年第4期46卷 209-215页

作者：钟若瑛宋伟许贝朱成业邓维南昌航空大学通航学院南昌330063 南昌航空大学飞行器工程学院南昌330063

针对飞机燃油系统方案设计阶段的重心计算及详细设计阶段截面轮廓具有明确变化规律的金属燃油箱基体结构设计,提出了一种基于知识工程,以设计流程化和模型参数化为典型特征的飞机燃油箱参数化布局及结构建模方法,定制了标准化的飞机燃... 详细信息

针对飞机燃油系统方案设计阶段的重心计算及详细设计阶段截面轮廓具有明确变化规律的金属燃油箱基体结构设计,提出了一种基于知识工程,以设计流程化和模型参数化为典型特征的飞机燃油箱参数化布局及结构建模方法,定制了标准化的飞机燃油箱建模流程,并在建模流程化的基础上实现飞机燃油箱布局及结构建模参数化,通过对具有典型结构特征的飞机燃油箱进行参数化设计和重心计算,该技术针对截面轮廓具有明确变化规律的燃油箱进行建模,能够提高飞机燃油系统的设计柔性,提高设计效率。

关键词：燃油箱设计流程化设计参数化设计知识工程 CATIA

Utility and Safety of Intrathecal Methotrexate Treatment in Severe Anti-N-methyI-D-aspartate Receptor Encephalitis： A Pilot Study

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Chinese Medical Journal 2018年第2期131卷 156-160页

作者： Xun-Zhe Yang Hua-Dong zhu Hai-Tao Ren Yi-cheng zhu Bin Peng Li-Ying Cui Hong-Zhi Guan Department of Neurology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Department of Emergency Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Center of Neuroscience Chinese Academy of Medical Sciences Beijing 100730 China

Background： Anti-N-methyl-D-aspartate receptor （anti-NMDAR） encephalitis is a treatable autoimmune neurologic syndrome that occurs with or without tumor association. However, some severe cases are refractory to systemic immunotherapy. This pilot study aimed to evaluate the utility and safety of intrathecal methotrexate injection for severe patients with anti-NMDAR encephalitis who did not respond to first-line immunotherapy. Methods： Intrathecal injections with methotrexate and dexamethasone were performed weekly in four legible patients within consecutive 4 weeks. Cerebrospinal fluid （CSF） was collected at baseline and each time of intrathecal injection lbr identification of anti-NMDAR antibody titers. Results： Significant clinical improvement was observed in three patients associated with a stepwise decrease of CSF anti-NMDAR antibody titers （maximum： 1/320 to minimum： 1/10）. After 2 months of follow-up, they were able to follow simple commands and had appropriate interactions with people （modified Rankin scale [mRS] of 0-2）. At 12 months of follow-up, they all had returned to most activities of daily life （.mRS of 0）, and no relapses were reported. One patient showed no clinical improvement and died of neurologic complications. Conclusions： lntrathecal treatment may be a potentially useful supplementary therapy in severely affected patients with anti-NMDAR encephalitis. Further large cohort study and animal experiment may help us elaborate the utility of intrathecal injection of methotrexate and its mechanism of action.

关键词： Anti-N-methyl-D-aspartate Receptor Encephalitis Injections Methotrexate

Drainage-induced ground response in a twin-tunnel system through analytical prediction over the seepage field

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Underground Space 2022年第3期7卷 408-418页

作者： cheng-wei zhu Wei Wu Hong-wei Ying Xiao-nan Gong Pan-pan Guo Research Center of Coastal and Urban Geotechnical Engineering HangzhouChina Institut fur Geotechnik Universitat fur BodenkulturFeistmantelstrasse 4A-1180 ViennaAustria Institute of Geotechinical Engineering Hohai UniversityNanjingChina

Leakage-induced hydraulic and ground responses in a twin-tunnel system are analyzed via the proposed analytical solution on the seepage *** seepage continuity conditions are rigorously satisfied at the interface between the ground and the tunnel lining,in terms of both water pressure and seepage *** analytical solution is verified by comparing the results of numerical simulations.A detailed parametric analysis is carried out to explore the effect of tunnels’spatial layouts and degraded waterproof facilities on leakageinduced hydraulic and ground response,including head decline,water inflow and ground surface *** results show that the often used single tunnel model tends to overestimate the pore pressure on the lining along with water inflow into the tunnel,and underestimate the leakage-induced ground settlement.

关键词： Twin tunnel Leakage Head decline Water inflow Ground settlement

Discrimination of Transgenic Rice Based on Near Infrared Reflectance Spectroscopy and Partial Least Squares Regression Discriminant Analysis

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Rice science 2015年第5期22卷 245-249页

作者： ZHANG Long WANG Shan-shan DING Yan-fei PAN Jia-rong zhu cheng College of Ecology Lishui University College of Life Sciences Zhejiang University College of Life Sciences China Jiliang University

Near infrared reflectance spectroscopy （NIRS）, a non-destructive measurement technique, was combined with partial least squares regression discrimiant analysis （PLS-DA） to discriminate the transgenic （TCTP and mi166） and wild type （Zhonghua 11） rice. Furthermore, rice lines transformed with protein gene （OsTCTP） and regulation gene （Osmi166） were also discriminated by the NIRS method. The performances of PLS-DA in spectral ranges of 4 000-8 000 cm-1 and 4 000-10 000 cm-1 were compared to obtain the optimal spectral range. As a result, the transgenic and wild type rice were distinguished from each other in the range of 4 000-10 000 cm-1, and the correct classification rate was 100.0% in the validation test. The transgenic rice TCTP and mi166 were also distinguished from each other in the range of 4 000-10 000 cm-1, and the correct classification rate was also 100.0%. In conclusion, NIRS combined with PLS-DA can be used for the discrimination of transgenic rice.

关键词： near infrared reflectance spectroscopy genetically-modified food regulation gene protein gene partial least squares regression discrimiant analysis

Palladium-catalyzed Cascade Cyclization-Coupling Reaction of Benzyl Halides with N, N-Diallylbenzoylamide

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Chinese Chemical Letters 2003年第8期14卷 771-772页

作者： Yi Min HU Yu ZHANG Jian Lin HAN cheng Jian zhu Yi PAN School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093

A novel type of palladium-catalyzed cascade cyclization-coupling reaction has been found. Reaction of N, N-diallylbenzoylamide 1 with benzyl halides 2 afforded the corresponding dihydropyrroles 3 in moderate to excel... 详细信息

关键词： Palladium Heck reaction benzyl halides cyclization cascade reaction.