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Yield and quality properties of silage maize and their influencing factors in China

Science China(Life Sciences) 2022年第8期65卷 1655-1666页

作者： Mengying Zhao Yinping Feng Yue Shi Haihua Shen Huifeng Hu Yongkai Luo Longchao Xu Jie Kang aijun xing Shaopeng Wang Jingyun Fang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Silage maize(Zea mays L.) is one of the most important forages in the world, and its yield and quality properties are critical parameters for livestock production and assessment of forage values. However, relationships between its yield and quality properties and the controlling factors are not well documented. In this study, we collected 5,663 observations from 196 publications across the country to identify the relationships between yield and quality properties of silage maize and to assess the impact of management practices and climatic factors on its yield and quality in China. The average dry matter yield of silage maize was(19.98±6.93) Mg ha^(-1), and the average value of crude protein, ether extract, crude ash, crude fiber, acid detergent fiber, neutral detergent fiber, nitrogen-free extract, and relative feed value was 7.86%±1.71%, 2.53%±1.01%, 5.05%±1.66%,23.97%±6.34%, 27.62%±7.12%, 51.60%±9.85%, 59.68%±7.72%, and 131.17±31.49, respectively. In general, its nutritive value decreased as its yield increased. Increasing planting density could increase the yield but inhibit the nutritive values, while increasing fertilization could benefit the nutritive values. Geographically, the yield increased and the nutritive value decreased from warm(south) to cold(north) regions. The length of growth duration was a major controlling factor for the patterns of these properties. Our findings provide insights for police-makers to make strategy for achieving high yield and good quality of silage maize and help local people to implement better management practices.

关键词： silage maize yield quality management practices climatic factors

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Species richness and composition of shrub-encroached grasslands in relation to environmental factors in northern China

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Journal of Plant Ecology 2019年第1期12卷 56-66页

作者： Luhong Zhou Haihua Shen Leiyi Chen He Li Pujin Zhang Xia Zhao Taoyu Liu Shangshi Liu aijun xing Huifeng Hu Jingyun Fang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyThe Chinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China University of Chinese Academy of Sciences No.19A Yuquan RdShijingshan DistrictBeijing 100049China Inner Mongolia Prataculture Research Center Chinese Academy of SciencesHohhot 010031China Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory of Earth Surface Processes of the Ministry of EducationPeking UniversityNo.5 Yiheyuan RdHaidian DistrictBeijing 100871China

Aims Shrub encroachment has taken place in many of China’s northern grasslands.This study attempts to answer the following questions:which plant communities are present in these shrub-encroached grasslands(SEGs)?What are the species richness and composition of these communities?Which environmental factors determine the spatial distribution thereof?Methods We investigated the community characteristics of 255 SEG plots with a size of 20 m×20 m at 69 locations across grasslands in northern China.In each plot,paired 1-m^(2) quadrats were estab-lished within shrub patches and the neighbouring grassy matrix to record herb species composition.The quantitative character-istics(abundance,coverage and height)of herbs were meas-ured in 0.25-m2 subquadrats,and soil samples were collected in the quadrats.Two-way indicator species analysis(TWINSPAN),detrended canonical analysis(DCA)and canonical correspond-ence analysis(CCA)were used for community clustering and ordination.Important Findings The DCA and TWINSPAN results suggested that the SEGs in northern China can be divided into six community types:Potentilla fruticosa+Carex atrofusca,Spiraea hypericifolia+Festuca ovina,Caragana acanthophylla+Stipa sareptana,Caragana microphylla+Leymus chinensis,Caragana microphylla+Stipa klemenzii and Caragana tibetica+Cleistogenes songorica.At a regional scale,climate and soil nutrients controlled the spatial patterns of species richness and community composition of the SEGs in northern China.Temperature exerted a negative impact,whereas precipitation and nutrients had positive effects on species richness.Among the environmental factors used,climate was the major controller of the variations in commu-nity structure.These results provide new insights into the community composition of SEGs in China and enrich the global dataset of SEGs.

关键词： CCA community composition northern China shrub-encroached grasslands TWINSPAN

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江西常绿阔叶林分类及其分布格局

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Journal of Plant Ecology 2023年第1期16卷 123-134页

作者： Yizhen Liu Haihua Shen Gang Ge aijun xing Zhiyao Tang Jingyun Fang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China School of Life Science Nanchang UniversityNanchang 330031China College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

常绿阔叶林是中国东部的演替顶极植被。江西省位于中国亚热带东部湿润常绿阔叶林区的腹心,拥有该区第二大面积的常绿阔叶林。尽管江西常绿阔叶林已有大量的研究,但其主要类型和分布格局与主要驱动因素仍不清楚。本研究采用植物群落清查... 详细信息

常绿阔叶林是中国东部的演替顶极植被。江西省位于中国亚热带东部湿润常绿阔叶林区的腹心,拥有该区第二大面积的常绿阔叶林。尽管江西常绿阔叶林已有大量的研究,但其主要类型和分布格局与主要驱动因素仍不清楚。本研究采用植物群落清查法调查了205个常绿阔叶林样方,样方包含了江西常绿阔叶林主要群系类型。采用双向指示种(TWINSPAN)和去趋势对应分析(DCA)进行了数量分类,确定各群落类型的标志种、指示种。使用Kruskal–Wallis非参数检验比较了不同群落类型的地形和气候差异,并采用冗余分析(RDA)和变差分解的方法,区分地形、气候以及样方间距离对不同类型群落分布的影响。研究结果表明,江西常绿阔叶林可分为丘陵常绿阔叶林、沟谷季雨林、山地典型常绿阔叶林和山地云雾常绿阔叶林。这4类常绿阔叶林的分布受地形和气候条件的驱动,其分布格局也反映了这4类常绿阔叶林类型间的生物地理差异。本研究为构建中国东部湿润区常绿阔叶林的高级分类系统提供基础资料和重要参考。同时,本研究还发现丘陵常绿阔叶林易受人为活动干扰,沟谷季雨林和山地典型常绿阔叶林拥有非常丰富的第三纪孑遗植物等,这些特征都暗示江西常绿阔叶林亟需开展更严格的保护实践。

关键词：亚热带常绿阔叶林指示种诊断种森林分类排序

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不同实习医务人员职业防护能力知信行现况调查

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现代医药卫生 2024年第3期40卷 421-426页

作者：郑杏王艾君于明光赵存跃山东大学护理与康复学院山东济南250012 山东大学齐鲁医院肿瘤内科山东济南250012 山东电力中心医院脊柱外科山东济南250001

目的对不同实习医务人员职业防护知信行能力进行横断面调查研究。方法 2021年3-9月采取方便整群抽样方法选取山东省2所医学院校正在临床实习的护士及医生进行职业防护知信行能力问卷调查,采取问卷星方式进行线上调查,共收集有效问卷452... 详细信息

目的对不同实习医务人员职业防护知信行能力进行横断面调查研究。方法 2021年3-9月采取方便整群抽样方法选取山东省2所医学院校正在临床实习的护士及医生进行职业防护知信行能力问卷调查,采取问卷星方式进行线上调查,共收集有效问卷452份,其中实习护士187名(本科64名、专科123名),实习医生265名(本科221名、专科44名)。应用SPSS25.0统计软件进行数据分析。结果实习医务人员职业防护知识与防护态度、防护知识与防护行为总体分布比较,差异均有统计学意义(P<0.05);不同类别实习医务人员职业防护知识、态度、行为总体分布比较,差异均有统计学意义(H=33.733、29.158、28.740,P<0.001);专科实习医生与本科实习护士及专科实习护士职业防护知识5个维度、职业防护态度2个维护及职业防护行为4个维护的总体分布比较,差异均有统计学意义(P<0.05)。结论管理者应加强对实习医务人员职业防护知识的培训,尤其是加强对实习医生职业防护能力的培训,从而降低其职业暴露发生率。

关键词：实习医务人员职业防护知信行横断面调查

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Synergistic modulation of Li nucleation/growth enabled by CNTswrapped lithiophilic CoP/Co_(2)P decorated hollow carbon polyhedron host for stable lithium metal anodes

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Nano Research 2023年第4期16卷 4961-4969页

作者： Zhicui Song Yuchi Liu Zihao Wang Jianxiong xing Chaohui Wei Wei Zou aijun Zhou Jingze Li School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Research and Development Center Tianqi Lithium Co.Ltd.Chengdu 610093China Lithium Resources and Lithium Materials Key Laboratory of Sichuan Province Tianqi Lithium CorporationChengdu 610000China

Infinite volume expansion and uncontrolled lithium dendrite growth are the main bottlenecks that greatly hinder the commercial application of lithium metal anodes.Herein,derived from zeolitic imidazolate framework(ZIF)-67,carbon nanotubes(CNTs)-wrapped and CoP/Co_(2)P uniformly distributed nitrogen-doped hollow porous polyhedron carbon(CNT-CoP@NC)is elaborately designed as lithium metal host.A hybrid of N-doping and metallic phosphides modifications improves the lithiophilicity and reduces the nucleation barrier,consequently leading to homogeneous nucleation and smooth deposition of metallic lithium,thus suppresses the growth of Li dendrites.Meanwhile,self-generated CNTs arrays efficiently reduce the local current density.Moreover,the reduced lithium is preferentially deposited into the hollow structure of CNT-CoP@NC and then filled the voids among the CNT-CoP@NC particles.This all-pervasive Li plating design can not only alleviate the volume effect,but also maximize the anode space utilization.Benefiting from these synergistic modulations,even with an ultra-thin(7.2μm)anode layer of CNT-CoP@NC host,a high Coulombic efficiency for more than 400 cycles and an extended lifespan of 1,700 h under 1 mA·cm^(−2)can be achieved.When paired with a competitive high mass loading(17.1 mg·cm^(−2))LiFePO4 cathode,a superb cycling stability(126.7 mAh·g^(−1)over 550 cycles)is recorded at 1 C.

关键词： lithium metal anodes metal organic framework hollow structure dendrite-free synergistic modulations

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Effects of seismic devices on transverse responses of piers in the Sutong Bridge

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Earthquake Engineering and Engineering Vibration 2015年第4期14卷 611-623页

作者： Shen xing Alfredo Camara Ye aijun State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Department of Civil and Engineering City UniversityLondonUnited Kingdom PhD

The Sutong Bridge in China opened to traffic in 2008, and is an arterial connection between the cities of Nantong and Suzhou. It is a cable-stayed bridge with a main span of 1,088 m. Due to a tight construction schedule and lack of suitable seismic devices at the time, fixed supports were installed between the piers and the girder in the transverse direction. As a result, significant transverse seismic forces could occur in the piers and foundations, especially during a return period of a 2500-year earthquake. Therefore, the piers, foundations and fixed bearings had to be designed extraordinarily strong. However, when larger earthquakes occur, the bearings, piers and foundations are still vulnerable. The recent rapid developments in seismic technology and the performance-based design approach offer a better opportunity to optimize the transverse seismic design for the Sutong Bridge piers. The optimized design can be applied to the Sutong Bridge(as a retrofit), as well as other bridges. Seismic design alternatives utilizing viscous fluid dampers(VFD), or friction pendulum sliding bearings(FPSB), or transverse yielding metallic dampers(TYMD) are thoroughly studied in this work, and the results are compared with those from the current condition with fixed transverse supports and a hypothetical condition in which only sliding bearings are provided on top of the piers(the girder can move "freely" in the transverse direction during the earthquake, except for frictional forces of the sliding bearings). Parametric analyses were performed to optimize the design of these proposed seismic devices. From the comparison of the peak bridge responses in these configurations, it was found that both VFD and TYMD are very effective in the reduction of transverse seismic forces in piers, while at the same time keeping the relative transverse displacements between piers and the box girder within acceptable limits. However, compared to VFD, TYMD do not interact with the longitudinal displacements of the girder, and have simpler detail

关键词： Sutong Bridge cable-stayed bridge seismic devices transverse response bridge piers viscous fluid dampers(VFD) friction pendulum sliding bearings(FPSB) transverse yielding metallic dampers(TYMD)

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急性缺血性脑卒中患者睡眠-觉醒生物节律变化与预后的关系研究

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天津医药 2024年第6期52卷 614-619页

作者：薛晶元小冬邢爱君王连辉马倩符永山张萍淑华北理工大学附属开滦总医院神经内科 063000 河北省神经生物机能重点实验室华北理工大学附属开滦总医院心内科

目的探讨大脑中动脉急性缺血性脑卒中患者昼夜睡眠-觉醒生物节律变化与预后的关系。方法选取大脑中动脉急性缺血性脑卒中患者71例为病例组,根据患者出院时改良Rankin评分,将其分为预后良好组(53例)和预后不良组(18例)。另纳入同期无急... 详细信息

目的探讨大脑中动脉急性缺血性脑卒中患者昼夜睡眠-觉醒生物节律变化与预后的关系。方法选取大脑中动脉急性缺血性脑卒中患者71例为病例组,根据患者出院时改良Rankin评分,将其分为预后良好组(53例)和预后不良组(18例)。另纳入同期无急性缺血性脑卒中且无脑血管狭窄者67例作为对照组。收集患者一般资料,比较2组昼夜生物节律、日间睡眠-觉醒节律、夜间睡眠-觉醒节律、昼夜睡眠-觉醒节律指标的差异。多因素Logistic逐步回归分析大脑中动脉急性缺血性脑卒中预后的影响因素。受试者工作特征(ROC)曲线分析相关变量的预测价值。结果病例组年龄、男性、高血压、糖尿病、高脂血症、吸烟及饮酒史比例均高于对照组。病例组日间稳定性低于对照组(P<0.05)。日间总睡眠时间、入睡后清醒时间、浅睡眠期、深睡眠期、非快速眼动(NREM)睡眠期、快速眼动(REM)睡眠期及深睡眠期占比、REM睡眠期占比均高于对照组,而REM睡眠潜伏期、浅睡眠期占比低于对照组(P<0.05)。夜间总睡眠时间、入睡后清醒时间、浅睡眠期、NREM睡眠期、REM睡眠期高于对照组,而入睡潜伏期、REM睡眠期占比低于对照组(P<0.05)。昼夜睡眠增多、日间睡眠增多、夜间睡眠效率低下比例高于对照组(P<0.05)。Logistic回归分析显示日间REM睡眠潜伏期是大脑中动脉急性缺血性脑卒中预后的影响因素。日间REM睡眠期ROC曲线下面积(AUC)为0.705,敏感度为0.811,特异度为0.611。结论大脑中动脉急性缺血性脑卒中后昼夜睡眠-觉醒节律呈失平衡状态,表现为日间稳定性差,日间睡眠增多,昼夜睡眠增多,夜间睡眠效率低下,日间REM睡眠期对大脑中动脉急性缺血性脑卒中预后有预测价值。

关键词：大脑中动脉卒中睡眠障碍昼夜节律性生物节律预后

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送端电网新能源承载能力研究

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山西电力 2024年第3期 30-34页

作者：闫桂红刘向民武海燕邢华栋张爱军慕腾内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司内蒙古呼和浩特010020 内蒙古自治区电力系统智能化电网仿真企业重点实验室内蒙古呼和浩特010020 内蒙古电力(集团)有限责任公司乌海超高压供电分公司内蒙古乌海016000

随着“碳达峰、碳中和”及构建以新能源为主体的新型电力系统战略目标的提出,国家将大力促进新能源的发展,西北部地区作为国家重要能源基地和“西电东送”重要送电端电网,“双高三低”特性明显,其新能源承载能力的研究显得尤为重要。针... 详细信息

随着“碳达峰、碳中和”及构建以新能源为主体的新型电力系统战略目标的提出,国家将大力促进新能源的发展,西北部地区作为国家重要能源基地和“西电东送”重要送电端电网,“双高三低”特性明显,其新能源承载能力的研究显得尤为重要。针对送端电网,提出一种考虑多种影响因素的新能源承载能力综合评估方法,依托综合仿真试验研究系统,统筹考虑常规机组开机水平、调峰能力(旋转备用容量)、负荷水平、断面潮流及新能源消纳优先级等实际运行因素,在满足电网安全稳定约束、电力平衡约束条件下,利用时域仿真法求得新能源承载能力,实现多种影响因素的解耦分析。通过对比论证,提出制约送端电网新能源承载能力的主要影响因素及对应承载规模,并提出新能源承载能力提升措施。

关键词：新能源承载能力评估方法影响因素送端电网

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Characterization and influencing factors of visit-to-visit blood pressurevariability of the population in a northern Chinese industrial city

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Chinese Medical Journal 2014年第6期127卷 1022-1026页

作者： Cao Huijun Wu Shouling Li Shuqiang Zhao Haiyan Ruan Chunyu Wu Yuntao xing aijun Department of Cardiology Chaoyang Hospital Capital Medical University Beijing 100020 China Department of Cardiology Kailuan Hospital Hebei United University Tangshan Hebei 063000 China Department of Cancer Immunology and AIDS Dana-Farber Cancer Institute Harvard Medical School Boston MA 02115 USA

Background Blood pressure variability(BPV) is a reliable prognostic factor for cardiovascular events. Currently there is a worldwide lack of large sample size studies in visit-to-visit BPV. Based on the Kailuan Study, we analyzed the visit-to-visit BPV of patients to investigate the range and influencing factors of BPV.Methods In 11 hospitals in the Kailuan Company, 4 441 patients received routine health checkups. Physical examination measured blood pressure(BP), body height, body weight, and waist circumference, and body mass index was calculated. Blood samples were analyzed for plasma total cholesterol(TC), triglyceride(TG), high-density lipoprotein cholesterol(HDL-C), low-density lipoprotein cholesterol(LDL-C), fasting blood glucose(FBG), and high-sensitivity c-reactive protein(hs-CRP). Results The effect of gender on systolic BPV was investigated. The average systolic BPV was 10.35 mmHg(1 mmHg=0.133 kPa) overall, 10.54 mmHg in males and 10.06 mmHg in females. Multivariate Logistic regression analysis revealed that the age(RR=1.022), systolic BP(SBP, RR=1.007), LDL-C(RR=1.098), and history of hypertension(RR=1.273) were significant risk factors for higher systolic BPV. We found that aging(RR=1.022), increased SBP(RR=1.007), and a history of hypertension(RR=1.394) were determinants of systolic BPV in males. The risk factors for systolic BPV of females were aging(RR=1.017), increased SBP(RR=1.009), increased LDL(RR=1.136), and increased TG(RR= 1.157).Conclusion Our findings indicated that the systolic BPV is closely associated with age, SBP and history of hypertension.

关键词： blood pressure variability age influencing factors

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基于冲击特征提取的旋转机械智能故障诊断

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航空动力学报 2023年第12期38卷 2973-2981页

作者：胡爱军孙俊豪邢磊向玲华北电力大学能源动力与机械工程学院机械工程系河北省电力机械装备健康维护与失效预防实验室河北保定071003

针对齿轮、轴承故障,提出了基于冲击特征提取胶囊网络的旋转机械智能故障诊断模型。在胶囊网络的构架基础上,将原始故障振动信号作为输入,通过构造首层小波核卷积层,针对性提取冲击故障特征,提高深度学习网络特征提取的可解释性。在小... 详细信息

针对齿轮、轴承故障,提出了基于冲击特征提取胶囊网络的旋转机械智能故障诊断模型。在胶囊网络的构架基础上,将原始故障振动信号作为输入,通过构造首层小波核卷积层,针对性提取冲击故障特征,提高深度学习网络特征提取的可解释性。在小波核卷积层之后扩展一层卷积层,强化首层小波核卷积层提取的特征,将强化的特征经初级胶囊层、数字胶囊层输出分类结果,从而构造了“端到端”的小波卷积胶囊网络模型。通过对各层提取的特征可视化分析,证明了该模型对故障振动信号的冲击特征具有良好的提取能力。3个不同实验平台的数据集验证结果表明不同故障类型、不同故障程度的齿轮及轴承的识别精度最高可达到100%,并具有良好的泛化能力。

关键词：冲击特征胶囊网络小波卷积核齿轮箱滚动轴承

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