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World Journal of Gastroenterology 2006年第36期12卷 5875-5877页

作者： Jrg Bojunga Christoph Sarrazin georg hess Stefan Zeuzem Internal Medicine Ⅱ Saarland University Hospital 66421 Homburg/Saar Germany Roche Diagnostics 68305 Mannheim Germany

AIM: To investigate plasma levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), an established marker of cardiac function, in patients with chronic hepatitis C during interferon-based antiviral therapy. METHODS: Using a sandwich immunoassay, plasma levels of NT-proBNP were determined in 48 patients with chronic hepatitis C at baseline, wk 24 and 48 during antiviral therapy and at wk 72 during ***: Plasma NT-proBNP concentrations were significantly increased (P < 0.05) at wk 24, 48 and 72 compared to the baseline values. NT-proBNP concentrations at baseline and wk 24 were closely correlated (r = 0.8; P < 0.001). At wk 24, 7 (14.6%) patients had NT-proBNP concentrations above 200 ng/L compared to 1 (2%) patient at baseline (P = 0.059). Six of these 7 patients had been treated with high-dose IFN-α induction therapy. In multiple regression analysis, NT-proBNP was not related to other clinical parameters, biochemical parameters of liver disease or virus load and response to ***: Elevated levels of NT-proBNP during and after interferon-based antiviral therapy of chronic hepatitis C may indicate the presence of cardiac dysfunction, which may contribute to the clinical symptoms observed in patients during therapy. Plasma levels of NT-proBNP may be used as a diagnostic tool and for guiding therapy in patients during interferon-based antiviral therapy.

关键词： Hepatitis C N-terminal pro-brain natriuretic peptide Interferon Cardiomyopathy Treatment side effects

CO_2 mitigation potential in farmland of China by altering current organic matter amendment pattern

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Science China Earth Sciences 2010年第9期53卷 1351-1357,1407-1417页

作者： CADISCH georg Institute of Plant Production and Agroecology in the Tropics and Subtropics University of Hohenheim

The estimation of the global warming mitigation potential in terrestrial ecosystems is of great importance for decision makers to adopt measures to increase soil organic carbon (SOC) as well as to reduce greenhouse gas (GHGs) emissions. In this paper, we compiled data published in peer-reviewed journals, and conducted a holistic analysis of the effects of organic matter amendment on soil organic carbon sequestration, methane (CH4) and nitrous oxide (N2O) emissions in paddy and upland systems. Results showed that organic matter amendment increased soil organic carbon content, and apparent conversion rate of organic matter carbon to soil organic carbon in paddies was constant, while that in uplands decreased along with amendment years at 25 years time scale. Organic matter amendment during the rice season led to large CH4-C emissions, e.g on average 99.5 g CH4-C per kg organic carbon input under intermittent flood conditions, and 191.7 g CH4-C per kg organic carbon input under continuous flood conditions, respectively. By alteration of organic matter amendment from rice season to off-rice upland crop season, estimated CH4-C emissions in China could be cut by 3.5 Tg yr-1, accounting for 63% of current CH4-C emissions (5.5 Tg). If organic matter amendment percentage was increased from current 30% to future 50% of organic matter production and by alteration of organic matter amendment from rice season to off-rice upland crop season, the equivalent CO2-C mitigation potential in farmland of China would be 49.2 Tg yr-1 at the 10th year organic matter amendment and 36.0 Tg yr-1 at the 30th year amendment. These findings are important not only for China but also for the other rice production countries to increase farmland global warming mitigation.

关键词： climate change global warming radiative forcing SOC GHGs CH4 N2O

Yield Improvement and Advanced Defect Control——Driving Forces for Modeling of Bulk Crystal Growth

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Journal of Rare Earths 2006年第Z1期24卷 200-207页

作者： georg Mueller Jochen Friedrich Crystal Growth Laboratory University Erlangen-Nürnberg (WW6) and Fraunhofer Institute of Integrated Systems and Device Technology (IISB) Martensstrasse 7 D-91058 Erlangen Germany Crystal Growth Laboratory University Erlangen-Nürnberg (WW6) and Fraunhofer Institute of Integrated Systems and Device Technology (IISB) Martensstrasse 7 D-91058 Erlangen Germany

Yield improvement and advanced defect control can be identified as the driving forces for modeling of industrial bulk crystal growth. Yield improvement is mainly achieved by upscaling of the whole crystal growth apparatus and increased processing windows with more tolerances for parameter variations. Advanced defect control means on one hand a reduction of the number of deficient crystal defects and on the other hand the formation of beneficial crystal defects with a uniform distribution and well defined concentrations in the whole crystal. This "defect engineering" relates to the whole crystal growth process as well as the following cooling and optional annealing processes, respectively. These topics were illustrated in the paper by examples of modeling and experimental results of bulk growth of silicon (Si), gallium arsenide (GaAs), indium phosphide (InP) and calcium fluoride (CaF2). These examples also involve the state of the art of modeling of the most important melt growth techniques, crystal pulling (Czochralski methods) and vertical gradient freeze (Bridgman-type methods).

关键词： yield improvement advanced defect control crystal growth

RESILIENCE 2.0： COMPUTER-AIDED DISASTER MANAGEMENT

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Journal of Systems Science and Systems Engineering 2017年第3期26卷 321-335页

作者： Gerhard Chroust georg Aumayr Institute for Telecooperation Johannes Kepler University Linz Austria Johanniter Osterreich Ausbildung und Forschung Vienna Austria

Many factors （larger population, more dependency on technology, more human-caused interference in the natural systems and equilibria, climate changes,... ） contribute to the seemingly growing number and severity of disasters. Additional exaggeration is generated by public media. As a consequence Disaster Prevention and Disaster Management must be given increased attention. The ultimate goal of Disaster Management is resilience of the affected system and thus the adequate and acceptable survival of the affected population. We discuss system behavior in the case of an assault or disturbance： from being fragile （loss of their functionality due to the assault） to being resilient （having the capacity ... of bouncing back to dynamic stability after a disturbance）, or even antifragile （being able to ＂learn＂ so as to improve disaster resilience）. Resilience 2. 0 identifies a new paradigm： modem Information and Communication Technologies （ICT） are employed as a basis for enabling and improving resilience of a system. ICT provide the basis for sufficient preparation before an assault, for quick recognition of, and for effective, efficient reactions to disasters. Only the coordinated intra- and interphase deployment of ICT promises sufficient success and can bring resilience to currently as yet fragile systems. We discuss stressors （time and performance pressure, physical and psychological stress on personnel） and problems due to damaged ICT-platforms and communication infrastructure. The basic message is that computer-aided Disaster Management is able to offers a new level of reactivity： Resilience 2.0.

关键词： Disaster vulnerability resilience human reaction hazard threat systemic reaction

On the Connection Between the Spectral Difference Method and the Discontinuous Galerkin Method

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Communications in Computational Physics 2011年第4期9卷 1071-1080页

作者： georg May Aachen Institute for Advanced Study in Computational Engineering Sciences RWTH Aachen UniversitySchinkelstr.252062 AachenGermany

In this short note we present a derivation of the Spectral Difference Scheme from a Discontinuous Galerkin(DG)discretization of a nonlinear conservation *** allows interpretation of the Spectral Difference Scheme as a particular discretization under the quadrature-free nodal DG ***,it enables identification of the key differences between the Spectral Difference Scheme and standard nodal DG schemes.

关键词： Spectral difference method discontinuous Galerkin method hyperbolic conservation laws quadrature-free schemes nodal schemes

Introducing robustness in model predictive control with multiple models and switching

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Control Theory and Technology 2014年第3期12卷 284-303页

作者： Sachin PRABHU Koshy georg Department of Telecommunication Engineering PES Institute of Technology Bangalore 560085 India PES Centre for Intelligent Systems Bangalore 560085 IndiaE

Model predictive control is model-based. Therefore, the procedure is inherently not robust to modelling uncertainties. Further, a crucial design parameter is the prediction horizon. Only offline procedures to estimate an upper bound of the optimal value of this parameter are available. These procedures are computationally intensive and model-based. Besides, a single choice of this horizon is perhaps not the best option at all time instants. This is especially true when the control objective is to track desired trajectories. In this paper, we resolve the issue by a time-varying horizon achieved by switching between multiple model-predictive controllers. The stability of the overall system is discussed. In addition, an introduction of multiple models to handle modelling uncertainties makes the overall system robust. The improvement in performance is demonstrated through several examples.

关键词： Receding horizon control Time-varying horizon Multiple models Switching Tracking Robustness

The quest for conditional independence in prospectivity modeling： weights-of-evidence, boost weights-of-evidence, and logistic regression

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Frontiers of Earth Science 2016年第3期10卷 389-408页

作者： Helmut SCHAEBEN georg SEMMLER Department of Geophysics and Geoinformatics TU Bergakademie Freiberg Freiberg 09596 Germany

The objective of prospectivity modeling is prediction of the conditional probability of the presence T = 1 or absence T = 0 of a target T given favorable or prohibitive predictors B, or construction of a two classes {0,1} classification of T. A special case of logistic regression called weights-of-evidence （WofE） is geolo- gists＇ favorite method of prospectivity modeling due to its apparent simplicity. However, the numerical simplicity is deceiving as it is implied by the severe mathematical modeling assumption of joint conditional independence of all predictors given the target. General weights of evidence are explicitly introduced which are as simple to estimate as conventional weights, i.e., by counting, but do not require conditional independence. Complementary to the regres- sion view is the classification view on prospectivity modeling. Boosting is the construction of a strong classifier from a set of weak classifiers. From the regression point of view it is closely related to logistic regression. Boost weights-of-evidence （BoostWofE） was introduced into prospectivity modeling to counterbalance violations of the assumption of conditional independence even though relaxation of modeling assumptions with respect to weak classifiers was not the （initial） purpose of boosting. In the original publication of BoostWofE a fabricated dataset was used to ＂validate＂ this approach. Using the same fabricated dataset it is shown that BoostWofE cannot generally compensate lacking condi- tional independence whatever the consecutively proces- sing order of predictors. Thus the alleged features of BoostWofE are disproved by way of counterexamples, while theoretical findings are confirmed that logistic regression including interaction terms can exactly com- pensate violations of joint conditional independence if the predictors are indicators.

关键词： general weights of evidence joint conditionalindependence naive Bayes model Hammersley-Cliffordtheorem interaction terms statistical significance

Recent Progress in Deciphering the Biosynthesis of Aspartate-Derived Amino Acids in Plants

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Molecular Plant 2010年第1期3卷 54-65页

作者： georg Jander Vijay Joshi Boyce Thompson Institute for Plant Research 1 Tower Road Ithaca NY 14850 USA

Plants are either directly or indirectly the source of most of the essential amino acids in animal diets. Four of these essential amino acids--methionine, threonine, isoleucine, and lysine--are all produced from aspartate via a well studied biosynthesis pathway. Given the nutritional interest in essential amino acids, the aspartate-derived amino acid pathway has been the subject of extensive research. Additionally, several pathway enzymes serve as targets for econom- ically important herbicides, and some of the downstream products are biosynthetic precursors for other essential plant metabolites such as ethylene and S-adenosylmethionine. Recent and ongoing research on the aspartate-derived family of amino acids has identified new enzyme activities, regulatory mechanisms, and in vivo metabolic functions. Together, these discoveries will open up new possibilities for plant metabolic engineering.

关键词： Metabolic regulation primary metabolism Arabidopsis.

Ethylene Controls Autophosphorylation of the Histidine Kinase Domain in Ethylene Receptor ETR1

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Molecular Plant 2008年第2期1卷 380-387页

作者： Jan Voet-van-Vormizeele georg Groth Heinrich-Heine-Universitat Biochemie der Pflanzen Universitatsstr. 1 40225 Duisseldorf Germany

Perception of the phytohormone ethylene is accomplished by a small family of integral membrane receptors. In Arabidopsis, five ethylene receptor proteins are known, including ethylene resistant I （ETR1）. The hydrophobic aminoterminal domain of these receptors contains the ethylene-binding site while the carboxyl-terminal part consists of a histidine kinase domain and a response regulator domain, which are well known elements found in bacterial two-component signaling. The soluble membrane-extrinsic carboxyl-terminal part of the receptor, which is likely to play an important role in signal transduction, showed intrinsic kinase activity when expressed and purified on its own. However, a correlation between signal input and autokinase activity was not established in these studies, as receptors were missing the trans- membrane amino-terminal sensor domain. Thus, it is still unclear whether autophosphorylation occurs in response to perception of the ethylene signal. Here, we report on autophosphorylation studies of purified full-length ETR1. Autoki- nase activity of the purified receptor is controlled by ethylene or by ethylene agonists like the π-acceptor compound cyanide. In fact, both signal molecules were able to completely turn off the intrinsic kinase activity, Furthermore, the observed inhibition of autophosphorylation in ETR1 by both molecules could be prevented when the ethylene antagonist 1-methyl-cyclopropene （MOP） was applied.

关键词： ethylene pathway phytohormone receptor membrane protein two-component system signaltransduction Arabidopsis thaliana,

Regulation of RNase E during the UV stress response in the cyanobacterium Synechocystis *** 6803

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mLife 2023年第1期2卷 43-57页

作者： Satoru Watanabe Damir Stazic Jens georg Shota Ohtake Yutaka Sakamaki Megumi Numakura Munehiko Asayama Taku Chibazakura Annegret Wilde Claudia Steglich Wolfgang R.hess Faculty of Biology Genetics and Experimental BioinformaticsUniversity of FreiburgFreiburgGermany Department of Bioscience Tokyo University of AgricultureSetagayakuTokyoJapan School of Agriculture Molecular GeneticsIbaraki UniversityIbarakiJapan Faculty of Biology Molecular GeneticsUniversity of FreiburgFreiburgGermany Nexxiot Prime Tower(Hardstrasse 201)ZurichSwitzerland.

Endoribonucleases govern the maturation and degradation of RNA and are indispensable in the posttranscriptional regulation of gene expression.A key endoribonuclease in Gram-negative bacteria is RNase *** ensure an appropriate supply of RNase E,some bacteria,such as Escherichia coli,feedback-regulate RNase E expression via the rne 5′-untranslated region(5′UTR)in ***,the mechanisms involved in the control of RNase E in other bacteria largely remain *** rely on solar light as an energy source for photosynthesis,despite the inherent ultraviolet(UV)*** this study,we first investigated globally the changes in gene expression in the cyanobacterium Synechocystis *** ^(6)803 after a brief exposure to *** the 407 responding genes 2 h after UV exposure was a prominent upregulation of rne mRNA ***,the enzymatic activity of RNase E rapidly increased as well,although the protein stability *** unique response was underpinned by the increased accumulation of full-length rne mRNA caused by the stabilization of its 5′UTR and suppression of premature transcriptional termination,but not by an increased transcription *** of RNA 3′ends and in vitro cleavage assays revealed that RNase E cleaves within a stretch of six consecutive uridine residues within the rne 5′UTR,indicating *** observations suggest that RNase E in cyanobacteria contributes to reshaping the transcriptome during the UV stress response and that its required activity level is secured at the RNA level despite the enhanced turnover of the protein.

关键词： cyanobacteria protein turnover ribonuclease stress response