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Effects of plant intraspecific variation on the prediction of C_(3)/C_(4)vegetation ratio from carbon isotope composition of topsoil organic matter across grasslands

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Journal of Plant Ecology 2021年第4期14卷 628-637页

作者： Wentao Luo Xiaoguang Wang karl Auerswald Zhengwen Wang Michael I.Bird Christopher J.Still Xiao-Tao Lv Xingguo Han Erguna Forest-Steppe Ecotone research Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China College of Environment and resources Dalian Minzu UniversityDalian 116600China Technische Universität München Lehrstuhl für GrünlandlehreAlte Akademie 1285350 Freising-WeihenstephanGermany College of Science and Engineering and ArC Centre of Excellence for Australian Biodiversity and Heritage James Cook UniversityCairnsQueensland 4870Australia Department of Forest Ecosystems and Society Oregon State UniversityCorvallisORUSA State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

Aims Understanding the patterns and drivers of carbon isotope discrimination(13Δ)in C_(3)and C_(4)functional groups is critical for predicting C_(3)/C_(4)vegetation ratio from the isotopic composition of soil organic *** this study,we aimed to evaluate how intraspecific variation will modify functional group-level 13Δvalues and the associated prediction of C_(3)/C_(4)vegetation *** We investigated 13Δof 726 individual plants(96 species;C_(3)and C_(4)functional groups)and topsoil organic matter in 26 grassland communities along an aridity gradient in northern *** fraction of C_(4)contribution was calculated with mixing models that considered:(i)both intra-and interspecific effects on the 13Δvalues of C_(3)and C_(4)functional groups;(ii)only interspecific effects;or(iii)none of these *** Findings We found divergent responses of plant 13Δat the intraspecific level to the changes of aridity across the *** 13Δof both C_(3)and C_(4)functional groups was negatively correlated with an aridity index,with higher sensitivity for C_(3)than for C_(4)functional *** 13Δvariation played a key role in driving the total 13Δvariations of C_(3)*** such intraspecific effect in mixing models led to a greatly increased fraction of C_(4)contribution to soil organic carbon.A correction for the effects of intraspecific variation is therefore essential for correctly inferring C_(3)/C_(4)vegetation ratio in the *** findings provide basic information for the reconstruction of past vegetation change from bulk materials in arid and semiarid biomes.

关键词： arid and semiarid grasslands interspecific variation intraspecific variation soil organic matter two-member mixing models vegetation ratio

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Sugar concentration influences decision making in Apis mellifera *** during early-stage honey storage behaviour

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Open Journal of Animal Sciences 2013年第3期3卷 210-218页

作者： Mark K.Greco Johann Lang Peter Gallmann Nicholas Priest Edward Feil karl Crailsheim Department of Biology and Biochemistry University of BathBathUK INVErT Group Department of Electrical and Electronic EngineeringUniversity of BathBathUK Department für Klinische Veterinarmedizin Vetsuisse-FakultatUniversitat BernBernSwitzerland Swiss Bee research Institute Agroscope Liebefeld-Posieux Research Station(ALP)BernSwitzerland Institute for Zoology at the karl-Franzens-Universitat Graz Austria

Decision making in honeybees is based on information which is acquired and processed in order to make choices between two or more alternatives. These choices lead to the expression of optimal behaviour strategies such as floral constancy. Optimal foraging strategies such as floral constancy improve a colony’s chances of survival, however to our knowledge, there has been no research on decision making based on optimal storage strategies. Here we show, using diagnostic radioentomology, that decision making in storer bees is influenced by nectar sugar concentrations and that, within 48 hours of collection, honeybees workers store carbohydrates in groups of cells with similar sugar concentrations in a nonrandom way. This behaviour, as evidenced by patchy spatial cell distributions, would help to hasten the ripening process by reducing the distance between cells of similar sugar concentrations. Thus, colonies which exhibit optimal storage strategies such as these would have an evolutionary advantage and im- prove colony survival expectations over less efficient colonies and it should be plausible to select colonies that exhibit these preferred traits.

关键词： Honey Floral Constancy Nectar Foraging Behaviour Decision Making

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半透膜仪采集空气中多氯联苯采样速度与其结构和性质定量构效关系研究(英文)

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计算机与应用化学 2011年第1期28卷 6-10页

作者：朱秀华丁光辉 Walkiria Levy karl-Werner Schramm 王炜穆军中国大连交通大学环境与化学工程学院辽宁大连116028 中国大连海事大学环境科学与工程学院辽宁大连116026 Helmholtz Zentrum Munchen-German research Center for Environmental Health Institute of EcologicalChemistryIngolstadter Landstr.1D-85764 NeuherbergMunichGermany TUM Wissenschaftszentrum Weihenstephan fuer Emaehnmg und LandnutzungDepartment fuer Biowissenschaftliche GrundlagenWeihenstephaner Steig 2385350 FreisingGermany

根据MOPAC2009软件包中PM6算法得到的分子描述符研究半透膜仪(SPMDs)采集大气中多氯联苯(PCBs)采样速度(r_(air))的定量构效关系(QSPr)模型,并分析影响r_(air)的关键因素。以半经验PM6算法得到的分子量子化学描述符作为预测变量,采用偏... 详细信息

根据MOPAC2009软件包中PM6算法得到的分子描述符研究半透膜仪(SPMDs)采集大气中多氯联苯(PCBs)采样速度(r_(air))的定量构效关系(QSPr)模型,并分析影响r_(air)的关键因素。以半经验PM6算法得到的分子量子化学描述符作为预测变量,采用偏最小二乘算法(PLS)构建了r_(air)的QSPr模型。根据交叉验证,所得到的最佳模型中PLS成分解释的因变量的累积变异(Q^2_(cum))为0.683,这表明该模型具有良好的预测能力和稳健性。通过外部验证和将实验测得的r_(air)与预测得到的r_(air)进行比较,对所构建模型的稳定性和可靠性进行了验证,结果表明无论是训练组还是预测组,其预测值与实测值间均具有较好的线性关系,线性相关系数均大于0.8376。对PCBs采样速度r_(air)的主要影响因素为PCBs与SPMDs中甘油三油酸酯分子间的相互作用大小和为将PCBs溶解在甘油三油酸酯中形成洞穴所需能量要求。

关键词：空气采样速度 SPMD PCB PLS QSPr

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Genotype and Environment Interactions of Yields and Yield Components of Tea (Camellia sinensis) Cultivars in Kenya

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American Journal of Plant Sciences 2016年第6期7卷 855-869页

作者： karl W. Nyabundi P. Okinda Owuor Godfrey W. Netondo John K. Bore Tea research Institute Kenya Agricultural and Livestock Research Organization Kericho Kenya Department of Chemistry School of Physical and Biological Sciences Maseno University Maseno Kenya Department of Botany School of Physical and Biological Sciences Maseno University Maseno Kenya

The tea crop provides income and employment to rural populations in many countries. In Kenya, tea, which is the leading export commodity crop, is grown in highlands east and west of the rift Valley at altitudes ranging from 1300 m to 2700 m above mean sea level. Variable responses of tea genotypes to different environments have been demonstrated. This affects the growth, productivity, and quality of tea. However, most tea husbandry practices are uniform across tea growing regions leading to variations in yields and quality in the different environments. Understanding causes of variations in tea growth parameters and yields to varying environments is vital to optimizing husbandry practices for maximization of productivity. The responses in growth and yield parameters of clonal tea to locations of production and their contribution to yields were compared. A genotype × environment trial was conducted in three sites (Kangaita, Timbilil and Kipkebe). At each site, a trial comprising 20 cultivars was laid in a randomized complete design replicated 3 times. Yields, yield components and climatic data were collected then subjected to analysis of variance and regression analysis. There were significant (p ≤ 0.05) yield variations between clones and locations. Yields ranged from 5162 kg mt/ha on clone TrFK 303/577 at Kipkebe to 935 kg mt/ha/year on clone TrFK 7/3 in Kangaita, surpassing the maximum variation possible postulated in earlier studies. The responses of the tea yield components to weather parameters varied with genotypes and environments. Shoot growth rates in Timbilil (r = 0.476)) and shoot density (Kangaita (r = 0.652) significantly (p ≤ 0.05)) correlated with yields. Yield components and weather parameters contribution to the total yield also varied with locations. The variations demonstrated that not all yield components can be used universally as yield indicators for clonal selection in different locations. For optimal production, selected tea clones should the

关键词： Genotype Environment Weather Parameters Yields Yield Components

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Towards Green Electronics Packaging Technologies

Towards Green Electronics Packaging Technologies

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第四届电子封装国际研讨会

作者： Hansjrg Griese Jutta Mller karl-Heinz Zuber Herbert reichl Fraunhofer-Institut fr Zuverlssigkeit und Mikrointegration IZM Berlin/Germany(Fraunhofer Institute for Reliability and Microintegration) Technical University of Berlin/Germany

＜正＞Trends of growing consumption,decreasing product lifetime and new application fields in nearly all leading industry segments lead to an enormous increase of product numbers in electronics *** production,use as well as the end of life treatment of these products cause considerable environmental *** prevent damages of human health and the environment,a sustainable economic growth has to be realized and new products and process technologies should proof that they contribute to the solution of globai environmental *** this paper two new results in the field of board interconnection technology show how to do it.

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Acute and Sub-Acute Toxicity of Ethanolic Leaf Extracts of <i>rumex abyssinica</i>Jacq. (Polygonaceae) and <i>Mentha spicata</i>L. (Lamiaceae)

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Pharmacology & Pharmacy 2014年第3期5卷 309-318页

作者： Maud Kamatenesi Mugisha James Gakunga Ndukui Agnes Namutembi Paul Waako Ann-karl Borg karlson Patrick Vudriko Department of Biological Sciences School of Biosciences College of Natural Sciences Makerere University Kampala Uganda Department of Chemistry KTH Stockholm Sweden Department of Food Technology and Nutrition College of Agriculture and Environmental Sciences Makerere University Kampala Uganda Department of Pharmacology and Therapeutics College of Health Sciences Makerere University Kampala Uganda Department of Veterinary Pharmacy Clinics and Comparative Medicine College of Veterinary Medicine Animal Resources and Biosecurity Makerere University Kampala Uganda Department of Veterinary Pharmacy Clinics and Comparative Medicine College of Veterinary Medicine Animal Resources and Biosecurity Makerere Uni-versity Kampala Uganda

rumex abyssinica Jacq. (Polygonaceae) is locally used in management of allergies and female reproductive healthcare;whereas Mentha spicata L. (Lamiaceae) is used to treat gastrointestinal and respiratory distress, dandruff, halitosis and malaria in Uganda. Owing to the paucity of data on their safety profiles, this study evaluated the acute and sub-acute toxicities of 70% ethanolic leaf extracts of both plants in mice and Wistar albino rats. The oral acute toxicity of both plants was evaluated in Swiss mice of 7-8 weeks old (16-22 g) body weight and LD50 determined. Sub-acute toxicity was evaluated in Wistar albino rats (6 per group) at dose rates of 500, 1000 and 1500 mg/kg for 28 days. The LD50 of r. abyssinica and M. spicata in mice was 7727 mg/kg and 13,606 mg/kg body weight, respectively. General signs of toxicity due to large doses of both plants extract included hyperurination, abdominal muscle twitches and convulsions. In the sub-acute toxicity test, rats treated with both extracts did not exhibit any clinical signs of toxicity;no mortality and changes in body weight were observed. r. abyssinica did not cause significant changes in haematological indices, except a significant increase in HCT (p 0.05). However, a dose dependant significant decrease in HCT (p 0.05) and a significant increase (p 0.05) in the levels of WBC, LMY and MCHC were observed in rats treated with M. spicata extract. Biochemical test showed that both extracts caused a significant dose dependent increase (p 0.05) in levels of ALT and ALP. Marked increase in the levels of AST was also observed in rats treated with M. spicata extract. Of the two extracts, only rats treated with

关键词： Histopathology Mentha spicata rumex abyssinica Toxicity

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喷灌防止柑桔六月落果的效应

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东南园艺 1980年第4期 30-34页

作者： r.F Brewr karl Opitz F.Aljibury ken Hench 邵蕙超克恩县农场顾问美国加利福尼亚大学kearney田间试验站

六月落果长期以来一直是加利福尼亚柑桔栽培者的祸害,当气温骤然升高时,他们束手无策,只好听天由命。本文论述一个可能防止柑桔六月落果的办法。这篇文章在国际柑桔会议上介绍过。五十年来,种植在加利福尼亚和亚利桑那谷地的华盛顿脐橙... 详细信息

六月落果长期以来一直是加利福尼亚柑桔栽培者的祸害,当气温骤然升高时,他们束手无策,只好听天由命。本文论述一个可能防止柑桔六月落果的办法。这篇文章在国际柑桔会议上介绍过。五十年来,种植在加利福尼亚和亚利桑那谷地的华盛顿脐橙,幼果过量脱落曾被公认是栽培上的一个主要问题。

关键词：六月落果叶温试验结果植物表面温度水果柑桔果实产量

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用于智能卡的热活化胶膜（HAF）

用于智能卡的热活化胶膜（HAF）

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2001北京国际粘接技术研讨会

作者： karl Engeldinger r＆D tesa AG Hamburg（Germany）

＜正＞1.智能卡的现状2.模件埋置过程及控制3.用于埋置模件的胶粘剂体系4.用于DI卡的新型导电胶膜5.用于智能卡的胶膜的前景展望

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“Alas poor Yorick”: What retrospective analysis of canine skulls can tell us about the impact of environmental factors on health

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Open Journal of Animal Sciences 2013年第3期3卷 12-18页

作者： Luciano O. Valenzuela Kevin Chase Lawrence McGill Shawn Miller Mark Nielsen karl G. Lark ArUP Animal Reference Pathology Division Salt Lake City USA Department of Biology University of Utah Salt Lake City USA Department of Biology University of Utah Salt Lake City USA Laboratorio de Ecología Evolutiva Humana CONICET Universidad Centro de la Provincia de Buenos Aires Buenos Aires Argentina

Necropsies and extensive histological evaluation for clinical and sub-clinical disease of approximately three hundred Portuguese Water dogs are available as part of an ongoing study to assess their state of health at the end of life. Throughout life these dogs enjoyed a variety of lifestyles and environments. Here we carry out retrospective quantitative assessments of life-time dietary input and physical activity for each dog. To do this, collagens from skull vault bone and from dentine have been analyzed for ratios of stable isotopes to determine differences in diet that individual dogs experienced during late or early life respectively. robustness of skull bone (weight/unit of skull size) was used as a relative indicator of the amount of physical activity experienced during a dog’s lifetime. These environmental parameters were correlated with the frequency and severity of specific disease processes determined at necropsy. Both measures were shown to exert significant low-level

关键词： Portuguese Water Dog Necropsy Histopathology Exercise Nutrition Stable Isotope Skull Dentine Collagen

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核天体物理学──核物理和天体物理的相互影响(Ⅱ)

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物理 1993年第2期22卷 67-74页

作者：王荣平吕南姚冯达璇 Friedrich-karl Thielemann 彭秋和南京大学天文系

4.慢中子俘获过程直到现在,一个显而易见的问题是象锡、稀土族元素以及锕素等这些比铁还重的元素是如何形成的?结果证明是,这些元素的形成不可能是前面我们已经讨论过的带电原子核间的聚变过程.它们是通过一系列中子俘获和β衰变过程(... 详细信息

4.慢中子俘获过程直到现在,一个显而易见的问题是象锡、稀土族元素以及锕素等这些比铁还重的元素是如何形成的?结果证明是,这些元素的形成不可能是前面我们已经讨论过的带电原子核间的聚变过程.它们是通过一系列中子俘获和β衰变过程(分别简记为“s-过程”和“r-过程”),现在我们来讨论它们是怎样的过程.要克服重原子核的库仑位垒所需要的温度超过5×10～9K,如此高温之下将产生许多高能光子,它的效果是引起更多的光致裂变反应而不是结合成重原子核(参看关于II型超新星的讨论).因此,重于铁的元素主要是通过铁族元素作为种子核的中子俘获过程来产生.在氦燃烧(典型动能为30keV)时,由于在～(22)Ne和～(13)C核的(α,n)反应中产生的热中子是S-过程的主要中子源,很低的巾子丰度导致r。,,。,即两次接连俘获中子的时间间隔远远长于所涉及的不稳定核的卢衰变半衰期这个条件将确定S-过程沿着卢稳定的路径,正如图5所示.这个过程可以简要地描述如下.一个种子’‘Fe核,受到中子流的辐照,俘获一个中子形成”Fe.这个同仕素对于卢衰变是稳定的,所以它将俘获另一个中子.如此方式生成的同位素序列将继续下去,直到形成短寿命的”Fe.此...

关键词：核物理空间物理学核反应中微子

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