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Journal of Plant Ecology 2022年第6期15卷 1227-1240页

作者： xinran ke Huixing Kang Yanhong Tang Department of Ecology College of Urban and Environmental SciencesPeking UniversityBeijing 100871China

Leaf size varies conspicuously within and among species under different ***,it is unclear how leaf size would change with elevation,whether there is a general elevational pattern,and what determines the altitudinal variation of leaf *** thus aimed to address these questions by focusing on the broad-leaved herbaceous species at high altitudes on the northeastern Qinghai-Tibetan *** measured the leaf size,leaf length,leaf width and leaf mass per area for 39 broad-leaved herbaceous species inhabited in the open areas along two mountain slopes from 3200 to 4400 m at the Lenglongling and the Daban Mountain,the northeastern Qinghai-Tibetan *** analyzed the altitudinal patterns in leaf size in relation to leaf inclination and leaf surface features,and applied a leaf energy balance model to discuss the underlying *** size decreased significantly at higher *** altitudinal reduction of leaf size was mainly attributed to the reduction of leaf length,and differed in different species,and in leaves with different inclination and leaf surface features.A leaf energy balance model with local environmental measurements demonstrates that leaf temperature tracks air temperature more closely in small than in large leaves,and that the leaf-size impact is stronger at higher *** on the observational findings,we propose that the distribution upper-limit for broad-leaved herbaceous species would be at an elevation of about 5400 m on the northeastern Qinghai-Tibetan Plateau.

关键词： elevation leaf area leaf energy balance leaf length leaf mass per area

Contrasting altitudinal patterns of leaf UV reflectance and absorbance in four herbaceous species on the Qinghai-Tibetan Plateau

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Journal of Plant Ecology 2019年第2期12卷 245-254页

作者： Xin Li xinran ke Huakun Zhou Yanhong Tang Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityNo.5 Yiheyuan RoadHaidian DistrictBeijing 100871China key Laboratory of Cold Regions Restoration Ecology Qinghai ProvinceNorthwest Plateau Institute of BiologyChinese Academy of SciencesNo.23 Xinning RoadXining 810008China

Aims Alpine plants have to cope with intense ultraviolet(UV)radiation and its altitudinal *** has been argued that leaf UV reflec-tance and absorbance should play a central role in acclimation and adaptation to changes in UV radiation,but evidence is lim-ited from high altitudinal *** this study,we assessed whether leaf UV reflectance and leaf pigments jointly vary with altitude in alpine broadleaved herbaceous *** primary hypothesis is that leaves with higher UV reflectance should have lower UV absorbance and/or lower contents of photosynthetic *** Leaf UV reflectance,leaf UV absorbance and photosynthetic pig-ments(chlorophyll a and b,carotenoids)were examined in four broadleaved herbaceous species in relation to their habitat *** leaf surface reflectance and leaf extract absorbance at wavelengths of 305 and 360 nm were measured to examine the leaf optical and photochemical characteristics in the UV-B and UV-A bands,*** species included Saussurea katochaete Maxim.,Saussurea pulchra Lipsch.,Anaphalis lactea *** Rheum pumilum Maxim.,which are distributed along the same slope from 3200 to 4200 m in the Qilian Mountains,Qinghai-Tibetan *** Findings The leaf UV absorbance was approximately twice as high at 305 nm(UV-B)than at 360 nm(UV-A)for all species except *** the four species,the leaf UV absorbance was the highest and almost all values were within 2-6 Abs cm^(−2)(absorbance cm^(−2))in ***,but the lowest(frequently<1 Abs cm^(−2))were observed in *** *** showed significantly higher values at higher *** UV reflectance was generally higher at higher elevations for all species except for ***,and exhibited much larger altitudinal variations compared to leaf UV *** lactea showed a very high UV reflectance even at low *** the four species,photosynthetic pigments tended to decrease with an increase in leaf UV refl

关键词： altitudinal pattern leaf UV reflectance UV absorbance photosynthetic pigment UV environment

水稻冠层不同高度光合有效辐射动态与叶片光合作用特性研究

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北京大学学报（自然科学版） 2021年第4期57卷 723-732页

作者：朱婷康辉星柯心然张炎北京大学城市与环境学院生态学系北京100871

在当前CO_(2)环境以及600μmol/mol air的开顶箱中,测量水稻冠层离水田泥土45 cm和90 cm处光合有效辐射的变动以及叶片的动态光合速率,探讨高CO_(2)环境下光强变动与光合作用关系的潜在变化。结果表明:1)水稻冠层90 cm处的平均光强是45... 详细信息

在当前CO_(2)环境以及600μmol/mol air的开顶箱中,测量水稻冠层离水田泥土45 cm和90 cm处光合有效辐射的变动以及叶片的动态光合速率,探讨高CO_(2)环境下光强变动与光合作用关系的潜在变化。结果表明:1)水稻冠层90 cm处的平均光强是45 cm处的3~4倍,但晴天光强的时间变异系数比45 cm处低55%~60%;2)上部叶片有更高的饱和光合速率以及照后CO_(2)固定,下部叶片有较高的低光光合速率;3)高CO_(2)开顶箱冠层内部的光衰减百分比倾向于增大,上,下叶片的光合能力差异增大。因此,冠层不同高度的光环境可能同时影响叶片的稳定态和动态光合特性,高CO_(2)可能加大由不同冠层光环境差异造成的光合特性差异。

关键词：动态光合 CO_(2)升高光驯化水稻

Single-cell analyses reveal cannabidiol rewires tumor microenvironment via inhibiting alternative activation of macrophage and synergizes with anti-PD-1 in colon cancer

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药物分析学报:英文版 2023年第7期13卷 726-744页

作者： Xiaofan Sun Lisha Zhou Yi Wang Guoliang Deng xinran Cao Bowen ke Xiaoqi Wu Yanhong Gu Haibo Cheng Qiang Xu Qianming Du Hongqi Chen Yang Sun Department of Rheumatology and Immunology Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing UniversityNanjing210008China State key Laboratory of Pharmaceutical Biotechnology School of Life SciencesNanjing UniversityNanjing210023China Colon and Rectal Surgery Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing210001China Laboratory of Anesthesia and Critical Care Medicine Department of AnesthesiologyTranslational Neuroscience CenterWest China Hospital and State Key Laboratory of BiotherapySichuan UniversityChengdu610044China Genergy Bio-technology(Shanghai)Co. LtdShanghai200241China The First Affiliated Hospital of Nanjing Medical University Jiangsu Province HospitalNanjing210029China Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor The First Clinical College of Nanjing University of Chinese MedicineNanjing210023China General Clinical Research Center Nanjing First HospitalNanjing Medical UniversityNanjing210006China School of Basic Medicine&Clinical Pharmacy China Pharmaceutical UniversityNanjing210009China Department of General Surgery Shanghai Jiao Tong University Affiliated Sixth People's HospitalShanghai200030China Jiangsu key Laboratory of New Drug Research and Clinical Pharmacy Xuzhou Medical UniversityXuzhouJiangsu221004China

Colorectal tumors often create an immunosuppressive microenvironment that prevents them from responding to ***(CBD)is a non-psychoactive natural active ingredient from the cannabis plant that has various pharmacological effects,including neuroprotective,antiemetic,anti-inflammatory,and antineoplastic *** study aimed to elucidate the specific anticancer mechanism of CBD by single-cell RNA sequencing(scRNA-seq)and single-cell ATAC sequencing(scATAC-seq)***,we report that CBD inhibits colorectal cancer progression by modulating the suppressive tumor microenvironment(TME).Our single-cell transcriptome and ATAC sequencing results showed that CBD suppressed M2-like macrophages and promoted M1-like macrophages in tumors both in strength and ***,CBD significantly enhanced the interaction between M1-like macrophages and tumor cells and restored the intrinsic anti-tumor properties of macrophages,thereby preventing tumor ***,CBD altered the metabolic pattern of macrophages and related anti-tumor signaling *** found that CBD inhibited the alternative activation of macrophages and shifted the metabolic process from oxidative phosphorylation and fatty acid oxidation to glycolysis by inhibiting the phosphatidylinositol 3-kinase-protein kinase B signaling pathway and related downstream target ***,CBD-mediated macrophage plasticity enhanced the response to anti-programmed cell death protein-1(PD-1)immunotherapy in xenografted *** together,we provide new insights into the anti-tumor effects of CBD.

关键词： scRNA-seq scATAC-seq Cannabidiol Colorectal cancer Tumor microenvironment Macrophage

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PA热熔胶颗粒的压缩空气干燥模型

塑料工业 2023年第2期51卷 96-99,139页

作者：黄欣然朱建晓王克杨洁包建东南京理工大学自动化学院江苏南京210094 苏州康尼格电子科技股份有限公司江苏常熟215562

针对塑料工业中塑料颗粒干燥问题,研究了以压缩空气作为风源的热风干燥特性及其数学模型,为聚酰胺(PA)热熔胶颗粒干燥工艺提供参考。采用正交试验探索温度及风压对干燥的影响,比较了11种薄层干燥模型的适用性。结果得出不同风温下的水... 详细信息

针对塑料工业中塑料颗粒干燥问题,研究了以压缩空气作为风源的热风干燥特性及其数学模型,为聚酰胺(PA)热熔胶颗粒干燥工艺提供参考。采用正交试验探索温度及风压对干燥的影响,比较了11种薄层干燥模型的适用性。结果得出不同风温下的水分有效扩散系数Deff为1.0×10^(-9)~3.2×10^(-9)m^(2)/s。PA热熔胶颗粒的干燥活化能Ea为36.438 kJ/mol。描述干燥特性的最佳模型为Logarithmic模型,并进一步给出了0.25 MPa风压下与温度相关的干燥数学模型。

关键词：聚酰胺热熔胶塑料颗粒压缩空气干燥特性干燥模型

MRI表现为垂体后叶高信号消失的先天性肾性尿崩症1例

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中华全科医师杂志 2023年第6期22卷 644-646页

作者：张红鄢力冷洁许珂程昕然电子科技大学附属妇女儿童医院、成都市妇女儿童中心医院儿童遗传与内分泌代谢科成都611731

报道1例影像学表现为中枢性尿崩症的先天性肾性尿崩症患儿诊治经过。患儿因反复发热、呕吐于院外对症治疗后无明显好转,后因再次发热就诊,入院后发现血钠升高,多饮多尿,诊断为尿崩症。头颅MRI提示垂体后叶高信号消失,予以去氨加压素对... 详细信息

报道1例影像学表现为中枢性尿崩症的先天性肾性尿崩症患儿诊治经过。患儿因反复发热、呕吐于院外对症治疗后无明显好转,后因再次发热就诊,入院后发现血钠升高,多饮多尿,诊断为尿崩症。头颅MRI提示垂体后叶高信号消失,予以去氨加压素对症治疗后疗效欠佳,经基因检查提示先天性肾性尿崩症。

关键词：尿崩症,肾性儿童影像学

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CRH5A动车组制动安全环路优化方案研究

铁道机车车辆 2023年第6期43卷 146-151页

作者：刘克思张远东栾珂张欣冉中国铁路济南局集团有限公司青岛动车段山东青岛266011 中国铁路北京局集团有限公司北京100860 中车南京浦镇车辆有限公司南京210031 中车青岛四方车辆研究所有限公司山东青岛266031

针对CRH5A动车组运用过程中安全环路多次异常断开导致紧急制动施加且无法缓解的问题,阐述了CRH5A动车组紧急制动控制和制动安全环路的工作原理,对各触发源断开安全环路导致的紧急制动通过旁路实施缓解的可行性进行了分析,归纳了既有安... 详细信息

针对CRH5A动车组运用过程中安全环路多次异常断开导致紧急制动施加且无法缓解的问题,阐述了CRH5A动车组紧急制动控制和制动安全环路的工作原理,对各触发源断开安全环路导致的紧急制动通过旁路实施缓解的可行性进行了分析,归纳了既有安全环路方案通过旁路实施缓解方面存在的问题,提出了在CRH5A动车组既有制动安全环路中增设旁路开关的优化方案,可在特殊情况下旁路安全环路中的故障点对其触发的紧急制动实施缓解;同时还对旁路开关投用后动车组安全环路控制功能受限情况及其对行车安全影响进行了分析,给出了应急处置操作建议。

关键词： CRH5A动车组紧急制动制动安全环路旁路开关

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改进跟踪微分器在喷头墨点补偿中的应用

工业仪表与自动化装置 2023年第2期 34-40页

作者：杨洁朱建晓黄欣然王克包建东南京理工大学自动化学院江苏南京210094 苏州康尼格电子科技股份有限公司江苏常熟215562

3D打印封装技术是电子封装保护领域的新型工艺,双向打印过程中喷头平移和墨滴喷射之间的相对运动使墨滴实际位置与期望位置产生偏差,影响封装效果。在喷头到达打印位置前一段时间(墨滴飞行时间T f)喷射可以消除偏差,因此准确获取墨点具... 详细信息

3D打印封装技术是电子封装保护领域的新型工艺,双向打印过程中喷头平移和墨滴喷射之间的相对运动使墨滴实际位置与期望位置产生偏差,影响封装效果。在喷头到达打印位置前一段时间(墨滴飞行时间T f)喷射可以消除偏差,因此准确获取墨点具体喷射时间至关重要。提出一种改进跟踪微分器估计喷头速度,通过估计的速度值计算采样点到打印位置的移动时间进而得到各墨点喷射时刻,实现喷头墨点补偿。该方法基于位移信息可快速估计速度,有效滤除位置测量时带有的噪声,速度估计比较准确,无需基于对象模型,易于实现。仿真与实验验证该速度估计方法可较准确估计喷头速度值,响应速度较快,有效减小喷头双向打印过程中的墨点偏差,双向打印对准精度在23μm以内。

关键词：改进跟踪微分器速度估计墨点补偿 3D封装

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一种熔融单元的LQG伺服控制系统设计

工业仪表与自动化装置 2023年第1期 16-20页

作者：王克朱建晓杨洁黄欣然包建东南京理工大学自动化学院江苏南京210094 苏州康尼格电子科技股份有限公司江苏常熟215500

熔融单元是低压注塑设备的核心器件。为了更加稳定、精准的控制熔融单元的温度,该文研究熔融单元的温度控制特性,建立熔融单元温度控制的近似模型,通过绝对误差积分准则IAE性能指标对比pade近似和smith预估器下的PID控制器性能。选取pad... 详细信息

熔融单元是低压注塑设备的核心器件。为了更加稳定、精准的控制熔融单元的温度,该文研究熔融单元的温度控制特性,建立熔融单元温度控制的近似模型,通过绝对误差积分准则IAE性能指标对比pade近似和smith预估器下的PID控制器性能。选取pade近似进行线性二次型调节器LQR控制器设计,并将误差e作为中间状态量进行最优化控制,通过卡尔曼滤波器降低控制器输出电压扰动和温度传感器测量误差对控制器输出和系统输出的影响。通过仿真实验证明,该方法可将系统超调量降低为0,IAE指标表明系统可快速跟随设定值变化,且不存在稳态误差;LQR控制器性能指标达0.865;且控制器具有一定的鲁棒性能。

关键词：熔融单元 smith预估器 pade近似 LQR控制卡尔曼滤波器

基于神经网络的分布式电源统一等效建模及其在PSASP中的应用

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电网技术 2016年第4期40卷 1224-1230页

作者：李培强曾小军李欣然胡泽柯飞谭庄熙湖南大学电气与信息工程学院湖南省长沙市410082

随着分布式电源(distributed generation,DG)在电网中渗透率的日趋增大,分布式电源的统一等效建模成为目前电力系统仿真领域的基础研究,人工神经网络(artificial neural network,ANN)以其强非线性映射能力和自适应自学习能力为此问题的... 详细信息

随着分布式电源(distributed generation,DG)在电网中渗透率的日趋增大,分布式电源的统一等效建模成为目前电力系统仿真领域的基础研究,人工神经网络(artificial neural network,ANN)以其强非线性映射能力和自适应自学习能力为此问题的研究提供了有效途径,综述了各种神经网络模型在电力系统负荷建模中的应用,并比较其优劣。对Elman神经网络的反馈支路进行了改进,使之适应分布式电源统一等效建模的需要,提出了一种改进Elman神经网络模型接入电力系统分析综合程序PSASP的思路,仿真实例表明改进Elman神经网络能有效描述各种分布式电源的外特性,能够满足工程仿真的需要。

关键词：神经网络分布式电源等效建模 PSASP