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Global leaf nitrogen and phosphorus stoichiometry and their scaling exponent

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National Science Review 2018年第5期5卷 728-739页

作者： Di Tian Zhengbing Yan Karl J.niklas Wenxuan Han Jens Kattge Peter B.Reich Yongkai Luo Yahan Chen Zhiyao Tang Huifeng Hu Ian J.Wright Bernhard Schmid Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Max-Planck-Institute for Biogeochemistry State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of Life Sciences Capital Normal University Department of Plant Biology Cornell University Department of Forest Resources University of Minnesota Department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia10 Department of Evolutionary Biology and Environmental StudiesUniversity of Zurich Hawkesbury Institute for the Environment Western Sydney University Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural University

Leaf nitrogen(N) and phosphorus(P) concentrations constrain photosynthetic and metabolic processes,growth and the productivity of plants. Their stoichiometry and scaling relationships regulate the allocation of N and P from subcellular to organism, and even ecosystem levels, and are crucial to the modelling of plant growth and nutrient cycles in terrestrial ecosystems. Prior work has revealed a general biogeographic pattern of leaf N and P stoichiometric relationships and shown that leaf N scales roughly as two-thirds the power of P. However, determining whether and how leaf N and P stoichiometries, especially their scaling exponents, change with functional groups and environmental conditions requires further verification. In this study, we compiled a global data set and documented the global leaf N and P concentrations and the N:P ratios by functional group, climate zone and continent. The global overall mean leaf N and P concentrations were 18.9 mg gand 1.2 mg g, respectively, with significantly higher concentrations in herbaceous than woody plants(21.72 mg gvs. 18.22 mg gfor N; and 1.64 mg gvs. 1.10 mg gfor P). Both leaf N and P showed higher concentrations at high latitudes than low latitudes. Among six continents, Europe had the highest N and P concentrations(20.79 and 1.54 mg g) and Oceania had the smallest values(10.01 and 0.46 mg g). These numerical values may be used as a basis for the comparison of other individual studies. Further, we found that the scaling exponent varied significantly across different functional groups,latitudinal zones, ecoregions and sites. The exponents of herbaceous and woody plants were 0.659 and0.705, respectively, with significant latitudinal patterns decreasing from tropical to temperate to boreal zones. At sites with a sample size ≥10, the values fluctuated from 0.366 to 1.928, with an average of *** factors including the intrinsic attributes of different life forms, P-related growth rates and relative nutrient availa

关键词： leaf nitrogen phosphorus stoichiometry scaling exponent functional group biogeography

木焦油污染土壤中微生物特性的空间变异性研究

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应用生态学报 2005年第5期16卷 939-944页

作者：杨秀虹李适宇 Gran Bengtsson niklas Trneman 中山大学环境科学与工程学院环境科学系 Department of Ecology Lund UniversityS lvegatan37SE22362 LundSweden

运用地统计学方法研究了木焦油污染土壤中微生物量、微生物群落结构、微生物活性等的空间变异特征.分别采用26种主要磷脂类脂肪酸(PLFA)的总含量(totPLFA)、PLFA的第一主成分和第二主成分(PLFAPC1和PC2)以及土壤培养过程中CO2C的累积释... 详细信息

运用地统计学方法研究了木焦油污染土壤中微生物量、微生物群落结构、微生物活性等的空间变异特征.分别采用26种主要磷脂类脂肪酸(PLFA)的总含量(totPLFA)、PLFA的第一主成分和第二主成分(PLFAPC1和PC2)以及土壤培养过程中CO2C的累积释放量(Cre)来表征土壤中的微生物量、微生物群落结构以及微生物活性.结果表明,多数微生物特性指标均存在不同程度的空间自相关性,其半变异函数曲线可用带块金效应的球状模型进行拟合.变量的空间相关距离在2.50～16.60m之间.PLFAPC1、totPLFA和Cre均具有较强的空间依赖性,其相对结构变差(由结构性因素引起的空间变异)分别为82.3%、79.6%和64.7%,而PLFAPC2不存在明显的空间依赖性.克立格空间插值图表明,样地中存在几处微生物相对密集分布且代谢活性较高的区域,其中优势微生物菌群是由PLFAs16:1ω7t,cy17:0,18:1ω7和cy19:0所表征的革兰氏阴性细菌.土壤中主要污染物多环芳烃含量和空间分布是影响微生物特性空间分布格局的重要因素之一.

关键词：空间变异性微生物特性地统计学污染土壤磷脂类脂肪酸

Comparison of Different Immunologic Assays for Quantification of Human IL21 Production

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Comparison of Different Immunologic Assays for Quantificatio...

Robust Multi-Objective Optimization of Chromatographic Rare Earth Element Separation

第八届全国免疫学学术大会

作者： Jenny Huang Theresa Bengtsson niklas Ahlborg Mabtech AB SE-131 28 Stockholm Nacka Strand SwedenPh.D

IL-21 is primarily secreted by activated T cells, in particular CD4+ follicular and Th17 T cells, and regulates the development of T cells, B cells, NK cells and dendritic *** of IL-21 has been reported to contribute to diseases such as SLE and *** fundamental relevance of IL-21 as well as its involvement in inflammatory and autoimmune diseases highlights the need for development and evaluation of suitable immunoassays facilitating analysis of *** antibodies to human IL-21 were generated and used to develop sensitive capture ELISA and ELISpot *** assays were used to analyze IL-21 secretion by peripheral blood mononuclear cells(PBMC) after polyclonal(PHA) or specific stimulation(Tetanus toxoid;Candida albicans extract).Polyclonal activation of PBMC induced IL-21 production detectable by ELISpot and *** PBMC concentrations and pro-longed incubation times increased the number of IL-21-secreting cells found by ***-21 levels in supernatants, analyzed by ELISA, showed a reversed relationship with increasing cell concentrations and incubation times associated with a decrease in *** PBMC activated with specific stimuli, IL-21-producing cells could be detected by ELISpot whereas IL-21 levels in supernatants were not measurable by *** parallel, IL-17 production after specific stimuli, on the other hand, was detectable both by ELISpot and *** to enable detection of antigen-specific IL-21 responses by ELISA were *** were cultured in the presence of a m Ab blocking IL-21 from binding its *** that, antigen-specific IL-21 could be measured by *** results show that although IL-21 secretion is specifically induced by antigen, as seen in ELISpot, the secreted IL-21 is below detection limits and/or consumed by binding to ***, by preventing secreted IL-21 from binding to its receptor, antigen-specific IL-21 responses can be detected also by ELISA.

关键词： human IL21 human IL17 ELISpot ELISA

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Advances in Chemical Engineering and Science 2017年第4期7卷 477-493页

作者： Hans-Kristian Knutson Anders Holmqvist niklas Andersson Bernt Nilsson Department of Chemical Engineering Centre for Chemistry and Chemical Engineering Lund University Lund Sweden

Rare earth elements are strategic commodities in many countries, and an important resource for the growing modern technology industry. As such, there is an increasing interest for development of rare earth element processing, and this work is a part of further development of chromatography as a rare earth element separation process method. Process optimization is pivotal for process development, and it is common that several competing objectives must be regarded. Chromatographic separation processes often consider competing objectives, such as productivity, yield, pool concentration and modifier consumption, which leads to Pareto optimal solutions. Adding robustness to a process is of great importance to account for process disturbances and uncertainties but generally comes with reduced performance of the other process objectives as a trade off. In this study, a model-based robust multi-objective optimization was carried out for batch-wise chromatographic separation of the rare earth elements samarium, europium and gadolinium, which was considered highly un-robust due to the neighbouring peaks proximity to the product pooling horizon. The results from the robust optimization were used to chart the required operation point changes for keeping the amount of failed batches at an acceptable level when a certain level of process disturbance was introduced. The loss of process performance due to the gained robustness was found to be in the range of 10% - 20% reduced productivity when comparing the robust and un-robust Pareto solutions at Pareto points with identical yield. The methodology presented shows how to increase robustness to a highly un-robust system while still keeping multiple objectives at their optima.

关键词： Rare Earth Elements Chromatography Multi-Objective Optimization Robust Optimization

Highly conformable chip-in-foil implants for neural applications

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微系统与纳米工程(英文) 2023年第3期9卷 245-257页

作者： Thomas Stieglitz Calogero Gueli Julien Martens niklas Floto Max Eickenscheidt Markus Sporer Maurits Ortmanns Laboratory for Biomedical Microtechnology Department of Microsystems Engineering-IMTEKUniversity of FreiburgD-79110 FreiburgGermany BrainLinks-BrainTools//IMBIT University of FreiburgD-79110 FreiburgGermany Institute of Microelectronics University of UlmD-89081 UlmGermany

Demands for neural interfaces around functionality,high spatial resolution,and longevity have recently *** requirements can be met with sophisticated silicon-based integrated *** miniaturized dice in flexible polymer substrates significantly improves their adaptation to the mechanical environment in the body,thus improving the systems’structural biocompatibility and ability to cover larger areas of the *** work addresses the main challenges in developing a hybrid chip-in-foil neural *** considered(1)the mechanical compliance to the recipient tissue that allows a long-term application and(2)the suitable design that allows the implant’s scaling and modular adaptation of chip *** element model studies were performed to identify design rules regarding die geometry,interconnect routing,and positions for contact pads on *** edge fillets in the die base shape proved an effective measure to improve die-substrate integrity and increase the area available for contact ***,routing of interconnects in the immediate vicinity of die corners should be avoided,as the substrate in these areas is prone to mechanical stress *** pads on dice should be placed with a clearance from the die rim to avoid delamination when the implant conforms to a curvilinear body.A microfabrication process was developed to transfer,align,and electrically interconnect multiple dice into conformable polyimide-based *** process enabled arbitrary die shape and size over independent target positions on the conformable substrate based on the die position on the fabrication wafer.

关键词： neural positions shape

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固体火箭推进新型含能组分（英文）

固体火箭技术 2016年第6期39卷 765-774页

作者： Luigi T DeLuca Ilaria Palmucci Andrea Franzin Volker Weiser Volker Gettwert niklas Wingborg Marita Sjoblom 米兰理工大学航天科技系意大利米兰I-20156 弗劳恩霍夫化学技术研究所德国D-76327 瑞典国防研究机构瑞典通巴SE-14725

针对2种含金属粉的固体推进剂——用于空间推进的标准AP/HTPB推进剂及ADN/GAP新体系的推进剂,分析了其配方,比较了这2种配方的理论热化学和实验燃烧性能的优缺点。分析结果表明,含双金属燃料和双氧化剂及活性粘合剂的体系被认为是空间... 详细信息

针对2种含金属粉的固体推进剂——用于空间推进的标准AP/HTPB推进剂及ADN/GAP新体系的推进剂,分析了其配方,比较了这2种配方的理论热化学和实验燃烧性能的优缺点。分析结果表明,含双金属燃料和双氧化剂及活性粘合剂的体系被认为是空间探测任务的优化配方。仅讨论了实验室水平的测试,对于发动机的应用,需要进行全尺寸测试,以确保全面掌握此过程。

关键词：固体推进剂固体氧化剂金属燃料稳态燃速

世界卫生组织药品不良反应数据库全球信号管理方法简述

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中国药物警戒 2024年第7期21卷 836-840页

作者：彼得·希尔姆斯特伦姆杰弗里·鲍林岳群英 G.尼克拉斯·诺伦乌普萨拉监测中心瑞典乌普萨拉

世界卫生组织(WHO)药品不良反应病例报告数据库(VigiBase)自1978年起由乌普萨拉监测中心(UMC)开发和维护。目前VigiBase保存着超过3900万份匿名的患者疑似药品和疫苗不良反应报告(截至2024年6月)。为支持世界卫生组织国际药物监测计划(W... 详细信息

世界卫生组织(WHO)药品不良反应病例报告数据库(VigiBase)自1978年起由乌普萨拉监测中心(UMC)开发和维护。目前VigiBase保存着超过3900万份匿名的患者疑似药品和疫苗不良反应报告(截至2024年6月)。为支持世界卫生组织国际药物监测计划(WHO PIDM)成员国制定、实施和加强安全监测计划,UMC开发了多个系统、工具和方法,以促进VigiBase的使用。本文描述了6种vigi方法(vigiMethods):vigiGrade、vigiMatch、vigiRank、vigiPoint、vigiGroup和vigiVec。VigiBase数据来源依靠主动报告的药品不良反应,但药品不良反应漏报是一个主要问题。为提高大型数据库(如VigiBase)中病例处理的效率、质量和能力,人工智能增强方法正在不断发展,以满足管理日益增长的数据量需求。继续开发现有的和新的方法,将VigiBase和其他数据库中的报告内容转化为有价值的信息,对于全球所有国家的患者更安全地使用药物和疫苗至关重要。

关键词：药品不良反应数据库世界卫生组织全球不良反应信号安全数据库管理方法

The 2/3 scaling of twig nitrogen to phosphorus in woody plants

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Forest Ecosystems 2022年第4期9卷 521-528页

作者： Zhiqiang Wang Karl Jniklas Zeqing Ma Dechun Jiang Jianming Deng Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station Southwest Minzu UniversityChengdu610041China Institute of Qinghai-Tibetan Plateau Southwest Minzu UniversityChengdu610041China Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY14853USA Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China Chengdu Institute of Biology Chinese Academy of SciencesChengdu610041China State Key Laboratory of Grassland Agro-Ecosystem College of EcologyLanzhou UniversityLanzhou730000China

Background:Nitrogen(N)and phosphorus(P)are important elements for plant metabolism and ***fore,the quantification of the scaling relationship of N to P in plant organs can help us understand many fundamental ecological *** general scaling relationships between N and P in leaves and in fine roots have been *** compared to leaves and fine roots,however,little information is available on the N versus P scaling relationship in the stems of woody plants,especially for *** this study,a comprehensive dataset comprising 2,038 N=P paired observations for a total of 536 woody species was compiled and analyzed to determine whether a general scaling relationship ***:The global mean values of twig N and P concentrations and N:P ratios were 9.33 mg⋅g^(-1),1.12 mg⋅g^(-1) and 10.16,*** N and P concentrations and N:P ratios differed significantly within and across functional groups and *** all of the species,a uniform 0.67 scaling exponent of twig N to P was observed across different functional groups and biomes,i.e.,a 2/3-power scaling relationship was ***,this numerical value differed across different sites,albeit converging onto 0.67 with increasing sample *** total phosphorus was the largest contributor to the variation in the numerical value of the scaling ***:These results provide useful parameters for stoichiometric growth models,and advance our understanding of the mechanisms underlying plant nutrient *** study has potential implications in predicting responses of nutrient cycling in terrestrial ecosystem responses to changes in the environment.

关键词： Nitrogen Phosphorus Scaling exponents Twigs Woody plants

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针对航空航天领域进行外形优化的铣刀

现代制造 2015年第6期 72-72,74,75页

作者： niklas Lehming

耐热钢材、钛、复合材料和铝，这些都是航空和航天领域制造商所面临的一种挑战，即在大多数情况下很难用涂层刀具对这些材料进行经济性的切削加工。而这些敏感的零件需要的是一种安全且精确的加工。航空航天工业领域通过国际间技术引导... 详细信息

耐热钢材、钛、复合材料和铝，这些都是航空和航天领域制造商所面临的一种挑战，即在大多数情况下很难用涂层刀具对这些材料进行经济性的切削加工。而这些敏感的零件需要的是一种安全且精确的加工。航空航天工业领域通过国际间技术引导和策略性关键技术的融合，目前正以每年约28．4亿欧元的销售额成为推动欧洲经济增长的一个重要引擎。根据联邦德国航空航天工业联合会（BDLI）统计，仅在德国就有100000多人直接在该领域工作。

关键词：航空航天工业航天领域外形优化铣刀复合材料切削加工联邦德国涂层刀具