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Brain regulates weight bearing bone through PGE2 skeletal interoception: implication of ankle osteoarthritis and pain

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Bone Research 2024年第1期12卷 107-121页

作者： Feng Gao Qimiao Hu Wenwei chen jilong Li cheng Qi Yiwen Yan cheng Qian Mei Wan James Ficke Junying Zheng Xu Cao Department of Orthopedic Surgery Johns Hopkins University School of MedicineBaltimoreMaryland 21205USA Department of Biomedical Engineering Johns Hopkins University School of MedicineBaltimoreMaryland 21205USA

Bone is a mechanosensitive tissue and undergoes constant remodeling to adapt to the mechanical loading environment.However,it is unclear whether the signals of bone cells in response to mechanical stress are processed and interpreted in the brain.In this study,we found that the hypothalamus of the brain regulates bone remodeling and structure by perceiving bone prostaglandin E2(PGE2)concentration in response to mechanical loading.Bone PGE2 levels are in proportion to their weight bearing.When weight bearing changes in the tail-suspension mice,the PGE2 concentrations in bones change in line with their weight bearing changes.Deletion of cyclooxygenase-2(COX2)in the osteoblast lineage cells or knockout of receptor 4(EP4)in sensory nerve blunts bone formation in response to mechanical loading.Moreover,knockout of TrkA in sensory nerve also significantly reduces mechanical load-induced bone formation.Moreover,mechanical loading induces cAMP-response element binding protein(CREB)phosphorylation in the hypothalamic arcuate nucleus(ARC)to inhibit sympathetic tyrosine hydroxylase(TH)expression in the paraventricular nucleus(PVN)for osteogenesis.Finally,we show that elevated PGE2 is associated with ankle osteoarthritis(AOA)and pain.Together,our data demonstrate that in response to mechanical loading,skeletal interoception occurs in the form of hypothalamic processing of PGE2-driven peripheral signaling to maintain physiologic bone homeostasis,while chronically elevated PGE2 can be sensed as pain during AOA and implication of potential treatment.

关键词： pain elevated PGE2

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Small water bodies in China:Spatial distribution and influencing factors

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Science China Earth Sciences 2022年第8期65卷 1431-1448页

作者： Mingquan LV Shengjun WU Maohua MA Ping HUANG Zhaofei WEN jilong chen Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 401122China

Inland water bodies,including ponds,lakes,reservoirs,and rivers,provide extensive ecosystem services for human beings.Among these,small water bodies(SWBs),such as ponds and small reservoirs,are more common landscape features and important biogeochemical reactors.SWBs can significantly influence biogeochemical processes and hydrologic cycles.However,due to their small size,SWBs(0.1 ha)cover approximately 179300 km^(2),which is approximately 1.8%of the land area in China.In addition,the combined shoreline length of the water bodies was approximately 2157400 km.Of these water bodies,96.85%were SWBs,accounting for 17.85%of the total water area and 76.4% of the total shoreline length.Precipitation,terrain,and human activity cumulatively explained 45% of the variance in SWB distribution,with precipitation being the strongest climatic explanatory factor.Our results provide important data for determining the roles of SWBs in biogeochemical cycles,habitat protection,and hydrological cycles.

关键词： Small water body Pond Small reservoir China Spatial distribution

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Improve meat production and virus resistance by simultaneously editing multiple genes in livestock using Cas12i^(Max)

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Science China(Life Sciences) 2024年第3期67卷 555-564页

作者： jilong Ren Tang Hai Yangcan chen Ke Sun Zhiqiang Han Jing Wang Chongyang Li Qingwei Wang Leyun Wang Huabing Zhu Dawei Yu Wei Li Shanjiang Zhao State Key Laboratory of Animal Nutrition Key Laboratory of Animal GeneticsBreeding and Reproduction of Ministry of Agriculture and Rural AffairsInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China State Key Laboratoryf Stem Cell and Reproductive Biology Instituteof ZooogyChinese Academyof SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Beijing Farm Animal Research Center Institute of ZoologyChinese Academy of SciencesBeijing 100101China

The clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated gene(Cas) system is continually optimized to achieve the most efficient gene editing effect. The Cas12i^(Max), a Cas12i variant, exhibits powerful DNA editing activity and enriches the gene editing toolbox. However, the application of Cas12i^(Max)in large domestic animals has not yet been reported. To verify the efficiency and feasibility of multiple gene editing in large animals, we generated porcine fibroblasts with simultaneous knockouts of IGF2, ANPEP, CD163,and MSTN via Cas12i^(Max)in one step. Phenotypically stable pigs were created through somatic cell nuclear transfer technology. They exhibited improved growth performance and muscle quality. Furthermore, we simultaneously edited three genes in bovine fibroblasts. A knockout of MSTN and PRNP was created and the amino acid Q-G in CD18 was precisely substituted. Meanwhile, no off-target phenomenon was observed by sum-type analysis or off-target detection. These results verified the effectiveness of Cas12i^(Max)for gene editing in livestock animals and demonstrated the potential application of Cas12i^(Max)in the field of animal trait improvement for agricultural production.

关键词： Cas12i^(Max) gene editing livestock multiple trait improvement

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Monitoring forest dynamics in Africa during 2000- 2020 using a remotely sensed fractional tree cover dataset

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International Journal of Digital Earth 2023年第1期16卷 2212-2232页

作者： Xuexin Wei Yang Liu Lin Qi jilong chen Guoqin Wang Linxiu Zhang Ronggao Liu Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijingPeople’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijingPeople’s Republic of China United Nations Environment Programme-International Ecosystem Management Partnership BeijingPeople’s Republic of China

Africa is covered with extensive woodlands,savannas and rainforests.The tree cover of these biomes has been undergoing substantial changes in recent decades.However,the dynamics of forests in Africa are currently unclear,particularly in the woodlands and savanna areas covered by sparse trees.Here,we assessed the spatio-temporal trend of African forests from 2000 to 2020,using a 250-m resolution fractional tree cover product that can capture the variation of forest density in the widespread mixed vegetation landscapes of the continent.The tree cover trends,interannual change and hotspots of forest gain and loss were evaluated.Results showed that the African forest area increased at a rate of 3.59 million ha/year over the study period,reaching 589 million ha in 2020.Considerable forest gain and loss both occurred in Africa.The net change rate in woodlands’forest area was the fastest(2.28 million ha/year),followed by rainforests(0.80 million ha/year)and savannas(0.34 million ha/year).Hotspots of forest gain were concentrated in the north belt of woodlands and savannas,while forest loss primarily clustered in East and South Africa.This work would help African countries to monitor forest change and promote forest management to achieve the Sustainable Development Goals.

关键词： Forest gain forest loss tree cover Africa spatio-temporal dynamic

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Differences and Links between the East Asian and South Asian Summer Monsoon Systems:Characteristics and Variability

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Advances in Atmospheric Sciences 2017年第10期34卷 1204-1218页

作者： Ronghui HUANG Yong LIU Zhencai DU jilong chen Jingliang HUANGFU Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China Institute of Earth Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper analyzes the differences in the characteristics and spatio–temporal variabilities of summertime rainfall and water vapor transport between the East Asian summer monsoon（EASM） and South Asian summer monsoon（SASM） systems. The results show obvious differences in summertime rainfall characteristics between these two monsoon systems. The summertime rainfall cloud systems of the EASM show a mixed stratiform and cumulus cloud system, while cumulus cloud dominates the SASM. These differences may be caused by differences in the vertical shear of zonal and meridional circulations and the convergence of water vapor transport fluxes. Moreover, the leading modes of the two systems＇ summertime rainfall anomalies also differ in terms of their spatiotemporal features on the interannual and interdecadal timescales. Nevertheless, several close links with respect to the spatiotemporal variabilities of summertime rainfall and water vapor transport exist between the two monsoon systems. The first modes of summertime rainfall in the SASM and EASM regions reveal a significant negative correlation on the interannual and the interdecadal timescales. This close relationship may be linked by a meridional teleconnection in the regressed summertime rainfall anomalies from India to North China through the southeastern part over the Tibetan Plateau, which we refer to as the South Asia/East Asia teleconnection pattern of Asian summer monsoon rainfall. The authors wish to dedicate this paper to Prof. Duzheng YE, and commemorate his 100 thanniversary and his great contributions to the development of atmospheric dynamics.

关键词： East Asian summer monsoon South Asian summer monsoon spatiotemporal variability rainfall water vapor transport

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航道工程围堰施工技术应用研究

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现代工程科技 2024年第5期3卷 97-100页

作者：陈基隆广西壮族自治区桂林航道养护中心广西桂林541002

随着社会经济不断发展,港口航道工程项目也逐渐增多,对航道工程施工质量和使用性能提出了更高的要求。特别是在围堰施工方面,若该项工作落实不够到位,就会对航道施工及功能发挥造成极大的影响。因此,要结合区域地形条件和水文环境,对围... 详细信息

随着社会经济不断发展,港口航道工程项目也逐渐增多,对航道工程施工质量和使用性能提出了更高的要求。特别是在围堰施工方面,若该项工作落实不够到位,就会对航道施工及功能发挥造成极大的影响。因此,要结合区域地形条件和水文环境,对围堰类型进行确定,然后遵照工艺流程科学开展围堰桩体施工、围堰土方填筑等工作,为航道工程如期竣工提供有力保证。阐述了围堰的主要类型,对航道工程围堰施工技术要点进行了探究,并围绕实际工程案例探讨了围堰施工的具体方法,以保证围堰的施工质量。

关键词：航道工程围堰施工具体方法

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Establishment and application of both FLP and Cre site-specific recombination systems at the same position in the genome

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Chinese Science Bulletin 2000年第5期45卷 456-460页

作者： jilong chen Jie Liu Yulian Zhang Zhiwei chen Zhenhua Jin Chinese Acad Sci Inst Dev Biol Beijing 100080 Peoples R China

Both FRT-FRT and LoxP-LoxP sites that are the target sepuences of site-specific recombinases have been constructed in a vector, called C4LFY, using the recombinant DNA technigue. C4LFY also contains P elements, 2 exons and 1 intron of Drosophila yellow gene, yellow promoter and enhancers, and flanking DNA. Since C4LFY made use of two pairs of FRT and LoxP sites, this vector included two site-specific recombination systems. C4LFY was then integrated into Drosophila genome by P-element-mediated germ line transformation. in the presence of the FLP or Cre recombinase, either FLP/FRT or Cre/LoxP recombination reaction was successfully created at the same position in the genome. Using this system, the molecular basis of yellow gene expression and regulation during development have been investigated. Results indicate that the tissue-specific expression of yellow gene is directly regulated by transcriptional enhancers. in addition, the 5’ and 3’ genomic sequences flanking the yellow gene have been

关键词： site-specific recombination transgene gene expression and regulation cis-acting elements.

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竖直铯热管传热特性的实验和数值模拟

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化工进展 2024年第4期43卷 1711-1719页

作者：赵吉隆郭宇翔陈宏霞袁达忠杜小泽华北电力大学电站能量传递转化与系统教育部重点实验室北京102206 华北电力大学能源动力与机械工程学院北京102206 中国科学院工程热物理研究所北京100190 中国科学院大学北京100049

近年来,有关中温铯热管的研究较少,主要因为铯热管造价昂贵且铯金属化学性质活泼,开展实验难度较大,因此通过数值模拟方法对铯热管启动特性与内部相变等过程进行分析预测具有重要意义。首先,本文开展铯热管冷启动实验,并基于目前的热管... 详细信息

近年来,有关中温铯热管的研究较少,主要因为铯热管造价昂贵且铯金属化学性质活泼,开展实验难度较大,因此通过数值模拟方法对铯热管启动特性与内部相变等过程进行分析预测具有重要意义。首先,本文开展铯热管冷启动实验,并基于目前的热管模拟模型,利用UDF建立蒸发与冷凝的自适应模型,对比实验热管稳态壁温与数值模拟计算壁温,最大温差小于20K,且较好地呈现了热管末端的温度突降,证明了模型的准确性。其次,基于竖直铯热管变功率冷态启动实验,模拟获得铯热管启动过程中热管壁面温度及内部工质相态分布的演变过程;并利用壁面温度的平均差数值评价有效长度上的均温性。最后,通过模拟研究改变热管蒸发段长度(200mm和120mm)、加热功率(1028.2W和844.4W)及充液率(8.8%、12%和15%),对比分析其相态分布、温度分布及压力分布;综合热管有效工作长度、壁面均温性、蒸发段液相堆积与干烧现象,分析蒸发段长度与充液率的最佳配比,为热管的优化设计提供基础。

关键词：传热多相流数值模拟热管相分布均温性

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SiC MOSFET高温栅氧可靠性研究

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电源学报 2024年第1期22卷 147-152页

作者：刘建君陈宏丁杰钦白云郝继龙韩忠霖中国科学院大学微电子学院北京100049 中国科学院微电子研究所北京100029 株洲中车时代半导体有限公司株洲412001

碳化硅SiC(silicon carbide)具有优良的电学和热学特性,是一种前景广阔的宽禁带半导体材料。SiC材料制成的功率MOSFET(metal-oxide-semiconductor field-effect transistor)非常适合应用于大功率领域,而高温栅氧可靠性是大功率MOSFET最... 详细信息

碳化硅SiC(silicon carbide)具有优良的电学和热学特性,是一种前景广阔的宽禁带半导体材料。SiC材料制成的功率MOSFET(metal-oxide-semiconductor field-effect transistor)非常适合应用于大功率领域,而高温栅氧可靠性是大功率MOSFET最需要关注的特性之一。通过正压高温栅偏试验和负压高温栅偏试验对比了自研SiC MOSFET和国外同规格SiC MOSFET的高温栅氧可靠性。负压高温栅偏试验结果显示自研SiC MOSFET与国外SiC MOSFET的阈值电压偏移量基本相等,阈值电压偏移量百分比最大相差在4.52%左右。正压高温栅偏试验的结果显示自研SiC MOSFET的阈值电压偏移量较小,与国外SiC MOSFET相比,自研SiC MOSFET的阈值电压偏移量百分比最大相差11%。自研器件占优势的原因是在SiC/SiO2界面处引入了适量的氮元素,钝化界面缺陷的同时,减少了快界面态的产生,使总的界面态密度被降到最低。

关键词： SiC MOSFET 可靠性栅氧高温栅偏

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黑土区玉米生理生长特性及产量对不同秸秆覆盖与施肥量的响应

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排灌机械工程学报 2024年第6期42卷 627-632页

作者：刘继龙陈俊丰曹晓强李济桢吴耀宇东北农业大学水利与土木工程学院黑龙江哈尔滨150030 东北农业大学农业农村部农业水资源高效利用重点实验室黑龙江哈尔滨150030

为揭示秸秆覆盖量与施肥量对东北黑土区玉米生理生长特性的影响机制,设置3种秸秆覆盖量(0.5,1.0和1.5倍)和3种施肥量(80%,100%和120%)的交互试验和常规施肥无覆盖对照处理CK共10种处理,研究分析不同秸秆覆盖量与施肥量下玉米叶片净光合... 详细信息

为揭示秸秆覆盖量与施肥量对东北黑土区玉米生理生长特性的影响机制,设置3种秸秆覆盖量(0.5,1.0和1.5倍)和3种施肥量(80%,100%和120%)的交互试验和常规施肥无覆盖对照处理CK共10种处理,研究分析不同秸秆覆盖量与施肥量下玉米叶片净光合速率Pn、气孔导度Gs、胞间CO_(2)浓度Ci和叶绿素SPAD等光合特性指标及株高、产量及其构成要素等生长指标的变化规律,分析各处理生长指标与光合特性参数和产量之间的相关关系,并通过综合指数法优选出效果最优的秸秆覆盖与施肥模式.结果表明:秸秆覆盖和施肥均能提高叶片Pn,Gs和叶绿素SPAD,降低Ci,玉米功能叶片Pn和Gs均随生育时期先增加后减少,而Ci随生育时期先增加后降低;叶绿素整体变化趋势与Pn一致;各处理玉米产量随秸秆覆盖量增加先增加后减少,随施肥量增加而增加,除80%施肥量处理组外其他处理玉米产量较CK处理增加8.9%~21.7%;秸秆覆盖量为8000 kg/hm^(2),施肥量为336 kg/hm^(2)时对研究区域内玉米生长生理及增产效果最佳.

关键词：东北黑土区秸秆覆盖施肥量生长生理特性综合指数法

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