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Spectro-Microscopy of Living Plant Cells

Molecular Plant 2012年第1期5卷 14-26页

作者： klaus Hatter Alfred J. Meixner Frank Schleifenbaum Center for Plant Molecular Biology （ZMBP） Plant Physiology and Biophysical Chemistry University of Tubingen Auf der Morgenstelle 1 72076 Tuebingen Germany Institute for Physical and Theoretical Chemistry （IPTC） Nano-Optics University of Tubingen Auf der Morgenstelle 8 72076 Tubingen Germany

Spectro-microscopy, a combination of fluorescence microscopy with spatially resolved spectroscopic techni- ques, provides new and exciting tools for functional cell biology in living organisms. This review focuses on recent devel- opments in spectro-microscopic applications for the investigation of living plant cells in their native tissue context. The application of spectro-microscopic methods led to the recent discovery of a fast signal response pathway for the brassi- nosteroide receptor BRI1 in the plasma membrane of living plant cells. Moreover, the competence of different plant cell types to respond to environmental or endogenous stimuli was determined in vivo by correlation analysis of different optical and spectroscopic readouts such as fluorescence lifetime （FLT）. Furthermore, a new spectro-microscopic technique, fluorescence intensity decay shape analysis microscopy （FIDSAM）, has been developed. FIDSAM is capable of imaging low- expressed fluorophore-tagged proteins at high spatial resolution and precludes the misinterpretation of autofluorescence artifacts. In addition, FIDSAM provides a very effective and sensitive tool on the basis of F6rster resonance energy transfer （FRET） for the qualitative and quantitative determination of protein-protein interaction. Finally, we report on the quan- titative analysis of the photosystem I and II （PSI/PSII） ratio in the chloroplasts of living Arabidopsis plants at room tem- perature, using high-resolution, spatially resolved fluorescence spectroscopy. With this technique, it was not only possible to measure PSI/PSII ratios, but also to demonstrate the differential competence of wild-type and carbohydrate-deficient plants to adapt the PSI/PSII ratio to different light conditions. In summary, the information content of standard microscopic images is extended by several dimensions by the use of spectro-microscopic approaches. Therefore, novel cell physiolog- ical and molecular topics can be addressed and valuable insigh

关键词： Fluorescence microscopy FLIM FRET photosystems protein-protein interaction FIDSAM.

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Dynamic Analogue Initialization for Ensemble Forecasting

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Advances in Atmospheric Sciences 2013年第5期30卷 1406-1420页

作者：李珊容新尧刘赟刘征宇 klaus FRAEDRICH Department of Atmospheric and Oceanic Sciences School of Physics Peking University Chinese Academy of Meteorological Sciences Center for Climatic Research and Department of Atmospheric and Oceanic Sciences University of Wisconsin-Madison Max Planck Institute for Meteorology

This paper introduces a new approach for the initialization of ensemble numerical forecasting： Dynamic Analogue Initialization （DAI）. DAI assumes that the best model state trajectories for the past provide the initial conditions for the best forecasts in the future. As such, DAI performs the ensemble forecast using the best analogues from a full size ensemble. As a pilot study, the Lorenz63 and Lorenz96 models were used to test DAI＇s effectiveness independently. Results showed that DAI can improve the forecast significantly. Especially in lower-dimensional systems, DAI can reduce the forecast RMSE by ~50% compared to the Monte Carlo forecast （MC）. This improvement is because DAI is able to recognize the direction of the analysis error through the embedding process and therefore selects those good trajectories with reduced initial error. Meanwhile, a potential improvement of DAI is also proposed, and that is to find the optimal range of embedding time based on the error＇s growing speed.

关键词： initialization ensemble forecast analogue error growth

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Elliptic flow of direct photons in Au+Au collisions at 200 GeV

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Chinese Physics C 2010年第9期34卷 1433-1435页

作者：刘复明 Tetsufumi Hirano klaus Werner 朱燕 Institution of particle physics Huazhong Normal University Department of Physics The University of Tokyo Laboratoire SUBATECH University of Nantes-IN2P3/CNRS-Ecole desMines

The rapidity dependence of the elliptic flow of direct photons in Au＋Au collisions at√ s NN = 200 GeV are predicted,based on a three-dimensional ideal hydrodynamic description of the hot and dense *** rapidity dependence of the elliptic flow v 2 （y） of direct photons （mainly thermal photons） is very sensitive to the initial energy density distribution along longitudinal direction,which provides a useful tool to extract the realistic initial condition from measurements.

关键词： thermal photons elliptic flow hydrodynamics

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Rock Plasticity from Microtomography and Upscaling

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Journal of Earth Science 2015年第1期26卷 53-59页

作者： Jie Liu Reem Freij-Ayoub klaus Regenauer-Lieb School of Earth Science and Geological Engineering Sun Yat-Sen University School of Earth and Environment the University of Western AustraliaPerth WA 6000Australia Earth Science and Resource Engineering CSIROKensington WA 6151Australia School of Petroleum Engineering University of New South WalesSydney NSW 2052Australia

We present a workflow for upscaling of rock properties using microtomography and percolation theory. In this paper we focus on a pilot study for assessing the plastic strength of rocks from a digital rock image. Firstly, we determine the size of mechanical representative volume ele- ment （RVE） by using upper/lower bound dissipation computations in accordance with thermody- namics. Then the mechanical RVE is used to simulate the rock failure at micro-scale using FEM. Two cases of different pressures of linear Drucker-Prager plasticity of rocks are computed to compute the macroscopic cohesion and the angle of internal friction of the rock. We also detect the critical exponents of yield stress for sealing laws from a series of derivative models that are created by a shrinking/expanding algorithm. We use microtomographic data sets of two carbonate samples and compare the results with previous results. The results show that natural rock samples with irregular structures may have the critical exponent of yield stress different from random models. This unexpected result could have significant ramifications for assessing the stability of solid materials with internal structure. Therefore our pilot study needs to be extended to investigate the scaling laws of strength of many more natural rocks with irregular microstructure.

关键词： plastic strength rock mierotomography percolation theory upscaling.

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Deciphering fluid inclusions in high-grade rocks

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Geoscience Frontiers 2014年第5期5卷 683-695页

作者： Alfons van den Kerkhof Andreas Kronz klaus Simon Geowissenschaftliches Zentrum der Universitat Gottingen Goldschmidtstr.1-3 D 37073 GottingenGermany

The study of fluid inclusions in high-grade rocks is especially challenging as the host minerals have been normally subjected to deformation, recrystallization and fluid-rock interaction so that primary in- clusions, formed at the peak of metamorphism are rare. The larger part of the fluid inclusions found in metamorphic minerals is typically modified during uplift. These late processes may strongly disguise the characteristics of the ＂original＂ peak metamorphic fluid. A detailed microstructural analysis of the host minerals, notably quartz, is therefore indispensable for a proper interpretation of fluid inclusions. Cathodoluminescence （CL） techniques combined with trace element analysis of quartz （EPMA, LA- [CPMS） have shown to be very helpful in deciphering the rock-fluid evolution. Whereas high-grade metamorphic quartz may have relatively high contents of trace elements like Ti and A1, low- temperature re-equilibrated quartz typically shows reduced trace element concentrations. The result- ing microstructures in CL can be basically distinguished in diffusion patterns （along microfractures and grain boundaries）, and secondary quartz formed by dissolution-reprecipitation. Most of these textures are formed during retrograde fluid-controlled processes between ca. 220 and 500 ℃, i.e. the range of semi-brittle deformation （greenschist-facies） and can be correlated with the fluid inclusions. In this way modified and re-trapped fluids can be identified, even when there are no optical features observed under the microscope.

关键词： Fluid inclusionsGranuliteCharnockiteCathodoluminescenceLA-ICPMSQuartz

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Analysis of the Vibrissa Parametric Resonance Causing a Signal Amplification during Whisking Behaviour

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Journal of Bionic Engineering 2016年第2期13卷 312-323页

作者： Tatiana Volkova Igor Zeidis Hartmut Witte Manuela Schmidt klaus Zimmermann Technische Universiat Ilmenau Technical Mechanics Group 98693 Max-Planck-Ring 12 Ilmenau Germany Technische Universitat Ilmenau Biomechatronics Group 98693 Max-Planck-Ring 12 Ilmenau Germany Friedrich-Schiller-Universitat Jena Institute of Systematic Zoology and Evolutionary Biology with Phyletic Museum 07743 Erbertstrafle 1 Jena Germany

The paper deals with the mechanical vibrational motion ofvibrissae during natural exploratory behaviour of mammals. The theoretical analysis is based on a mechanical model of a cylindrical beam with circular natural configuration under an applied periodic force at the tip, which corresponds to the surface roughness of an investigated object. The equation of motion of the beam is studied using the Euler-Bemoulli beam theory and asymptotic methods of mechanics. It is shown that from the me- chanical point of view the phenomenon of parametric resonance of the vibrissa is possible. It means that the amplitude of forced vibrations of a vibrissa increases exponentially with time, if it is stimulated within a specific resonance frequency range, which depends on biomechanical parameters of the vibrissa. The most intense parametric resonance occurs, when the excitation frequency is close to the doubled natural frequency of free vibrations. Thus, it may be used to distinguish and amplify specific periodic components of a complex roughness profile during texture discrimination.

关键词： vibrissa whisking vibration tactile sensor beam theory parametric resonance

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Effects of lag time in forest restoration and management

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森林生态系统:英文版 2023年第4期10卷 504-515页

作者： klaus J.Puettmann Jürgen Bauhus Department of Forest Ecosystem and Society Oregon State UniversityCorvallisOR97331USA University of Freiburg Tennenbacherstr.479085FreiburgGermany

The increased speed of global change and associated high severity disturbances,in conjunction with the increasing suite of societal expectations on forests,suggest that the timeliness of interventions to encourage the adaptive capacity of ecosystems and to reduce negative impacts in regards to provision of ecosystem services is increasingly *** address this issue,we expand the concept of lag time as used in ecological discussions into a forest management *** this context,lag times have earlier starting and later ending points and can be separated into different *** components include the delay till detection,decision making,and implementation,followed by ecological lag time and the time till ecosystem services are provided at acceptable *** first three components are influenced by the availability of information,the lack of which can extend lag ***,the lengths of components are not simply additive but they *** example,treatment preparation due to a quicker detection can lead to shorter decision and implementation lag *** highlight the benefits of addressing the various components of lag time in forestry *** when considering adaptive capacity in times of global change,our analysis suggests that all aspects of the forestry sector are challenged to consider how to optimize lag ***,we propose that such issues need to be considered with any management action and are especially relevant in discussions whether the best strategy after disturbances or in the light of global change is to adopt a passive approach and let natural ecosystem processes play out on their own or whether active management is better suited to ensure a more rapid and fitting ecosystem response to facilitate the continued provision of ecosystem services.

关键词： Active versus passive restoration Management decisions Global change

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Borehole deformation based in situ stress estimation using televiewer data

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2475-2481页

作者： Hamid Roshan Danqi Li Ismet Canbulat klaus Regenauer-Lieb School of Minerals and Energy Resources Engineering University of New South WalesSydneyNSW2052Australia WA School of Mines MineralsEnergy and Chemical EngineeringCurtin UniversityPerthWA6102Australia

The knowledge of in situ stress is critical in safe and optimised extraction of minerals and energy *** situ stresses are either measured directly(***)or estimated indirectly(*** breakouts).Borehole breakout analysis for in situ stress estimation is considered a relatively simple and cost-efficient *** technique,however,poses certain limitations such as complexities with progressive formation of breakouts and it requires inputs such as rock failure parameters that are not often *** a result,significant effort has been made to develop new indirect methods for in situ stress *** deformation analysis using four-arm caliper has been recently proposed for in situ stress estimation and has shown promising *** this study,we demonstrate a new methodology that analyses the borehole televiewer data with the technique of borehole deformation analysis to estimate the in situ stresses through a field case *** advantages and challenges of using borehole televiewer data for stress estimation based on borehole deformation analysis are discussed and the best practice to obtain the reliable results is *** limitations of using fourarm caliper and borehole deformation analysis for in situ stress estimation are also discussed and it is shown how televiewer data can overcome such ***,the in situ stress results obtained from televiewer data and borehole deformation analysis are compared with independent in situ stress measurements to show the robustness and reliability of the proposed methodology.

关键词： In situ stress Borehole deformation Televiewer Elastic properties Downhole logging

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Structure complexity is the primary driver of functional diversity in the temperate forests of northeastern China

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Forest Ecosystems 2022年第4期9卷 511-520页

作者： Zhenghua Lian Juan Wang Chunyu Fan klaus von Gadow Research Center of Forest Management Engineering of State Forestry and Grassland Administration Beijing Forestry UniversityBeijing100083China Department of Forest Ecology School of Ecology and Nature ConservationBeijing Forestry UniversityBeijing100083China Faculty of Forestry and Forest Ecology Georg-August-University G€ottingenBüsgenweg 5D-37077GottingenGermany Department of Forest and Wood Science University of StellenboschStellenbosch7600South Africa

Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change. However, until now, these mechanisms were poorly understood in the temperate forests of northeastern China, which prevented the development of new management methods aimed at increasing functional trait diversity and thus ecological ***:In this study, we mapped functional diversity distributions using a Kriging Interpolation Method. A specific random forest model approach was adopted to test the importance ranking of 18 variables in explaining the spatial variation of functional diversity. Three piecewise structural equation models (pSEMs) with forest types as random effects were constructed for testing the direct effects of climate, and the indirect effects of stand structure on functional diversity across the large study region. Specific causal relationships in each forest type were also examined using 15 linear structural equation ***:Although environmental filtering by climate is important, stand structure explains most of the functional variation of the forest ecosystems in northeastern China. Our study thus only partially supports the stressdominance hypothesis. Several abundant species determine most of the functional diversity, which supports the mass ratio ***:Our results suggest that forest management aimed at increasing structural complexity can contribute to increased functional diversity, especially regarding the mixing of coniferous and broad-leaved tree species.

关键词： Functional diversity distribution Forest types Forest management Random forest Stand structure attributes Structural equation modeling

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Omega-3 fatty acids and mental health

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Global Health Journal 2020年第1期4卷 18-30页

作者： klaus W.Lange Institute of Psychology University of Regensburg93040 RegensburgGermany

Nutrition plays a key role in brain development,mental health,and psychiatric *** role of omega-3 polyunsaturated fatty acids in physical health is well established,and their role in mental health is becoming increasingly ***-3 fatty acids are involved in a wide range of physiological functions that are related to neurogenesis,neurotransmission,and neuroinflammation;therefore,they play fundamental roles in the development,functioning,and aging of the *** humans,dietary deficiencies of omega-3 fatty acids are associated with an increased risk of developing various psychiatric disorders,including depression,bipolar disorder,schizophrenia,dementia,attention-deficit/hyperactivity disorder,and *** particular,eicosapentaenoic and docosahexaenoic acid have been linked to the maintenance of mental health,and their deficits have been implicated in the pathophysiology of mental *** may be mediated by the modulation of inflammatory processes and their direct effects on neuronal membrane fluidity and receptor ***,randomized clinical trials that have investigated the therapeutic effects of omega-3 fatty acids have yielded inconclusive results,thereby limiting the use of these nutrients in psychiatric ***-quality clinical trials should be conducted to examine the efficacy of omega-3 fatty acids in preventing and treating mental *** undesirable side effects of omega-3 fatty acid supplementation should also be *** effects may become apparent after many years of administration,and therefore,they may not be detected in most cases.

关键词： Omega-3 fatty acids Mental health Neurodevelopmental disorders Dementia Depression Schizophrenia

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