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Transcriptional Regulation of Nutrient Exchange in Arbuscular Mycorrhizal Symbiosis

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Molecular Plant 2018年第12期11卷 1421-1423页

作者： Erik Limpens rene geurts Laboratory of Molecular Biology Department of Plant SciencesWageningen UniversityWageningen 6708PBThe Netherlands

Most land plants rely on the symbiosis with arbuscular mycor- rhizal (AM)fungi to acquire sufficient mineral nutrients from soils. Plants host AM fungi inside root cortex cells,where the fungus forms highly branched structures called *** are surrounded by a specialized host membrane across which nutrients are exchanged in a cooperative *** return for mineral nutrients,the fungus obtains sugars and fatty acids from the plant (Luginbuehl and Oldroyd,2017).

关键词： Transcriptional Regulation Nutrient Exchange

Rhizobium Lipo-chitooligosaccharide Signaling Triggers Accumulation of Cytokinins in Medicago truncatula Roots

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Molecular Plant 2015年第8期8卷 1213-1226页

作者： Arjan van Zeijl Rik H.M. Op den Camp Eva E. Deinum Tatsiana Charnikhova Henk Franssen Huub J.M. Op den Camp Harro Bouwmeester Wouter Kohlen Ton Bisseling rene geurts Department of Plant Sciences Laboratory of Molecular Biology Wageningen University Droevendaalsesteeg 16708 PB Wageningen The Netherlands Department of Systems Biophysics FOM institute AMOLF Science Park 104 1098 XG Amsterdam The Netherlands Department of Plant Sciences Laboratory of Plant Physiology Wageningen University Droevendaalsesteeg 1 6708 PB Wageningen The Netherlands Department of Microbiology IWWR Radboud University Nijmegen Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands College of Science King Saud University Post Office Box 2455 Riyadh 11451 Saudi Arabia

Legume rhizobium symbiosis is initiated upon perception of bacterial secreted lipo-chitooligosaccharides （LCOs）. Perception of these signals by the plant initiates a signaling cascade that leads to nodule formation. Several studies have implicated a function for cytokinin in this process. However, whether cytokinin accu- mulation and subsequent signaling are an integral part of rhizobium LCO signaling remains elusive. Here, we show that cytokinin signaling is required for the majority of transcriptional changes induced by rhizo- bium LCOs. In addition, we demonstrate that several cytokinins accumulate in the root susceptible zone 3 h after rhizobium LCO application, including the biologically most active cytokinins, trans-zeatin and iso- pentenyl adenine. These responses are dependent on calcium- and calmodulin-dependent protein kinase （CCaMK）, a key protein in rhizobial LCO-induced signaling. Analysis of the ethylene-insensitive Mtein21 Mtsickle mutant showed that LCO-induced cytokinin accumulation is negatively regulated by ethylene. Together with transcriptional induction of ethylene biosynthesis genes, it suggests a feedback loop negatively regulating LCO signaling and subsequent cytokinin accumulation. We argue that cytokinin accumulation is a key step in the pathway leading to nodule organogenesis and that this is tightly controlled by feedback loops.

关键词： Medicago truncatula cytokinin ethylene rhizobium lipo-chitooligosaccharides CRE1

MODELING SPATIAL AND TEMPORAL VARIATION OF A POLLUTANT IN WATER ENVIRONMENT USING THE CUBIC SPLINE SCHEME

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Journal of Hydrodynamics 2006年第6期18卷 688-697页

作者： YAN Min KAHAWITA rene College of Architecture and Civil Engineering Zhejiang University of Technology Hangzhou 310014 China Department of Civil Geological and Mining Engineering Ecole Polytechnique de Montréal Université deMontr6al Quebec H3C 3A7 Canada Department of Civil Geological and Mining Engineering Ecole Polytechnique de Montréal Université de Montréal Quebec H3C 3A7 Canada

The cubic spline integration scheme has been successfully applied for the first time to obtain solutions for the two-dimensional shallow water wave and transport equations. Its principal advantages are its high accuracy, low computational cost, and flexibility of application. The study quantitatively analyzed and predicted the variation in time and space of a solid pollutant in water environment. The infiltration, adsorption, solubility, advection, and diffusion related factors at different spatial and temporal scales were taken into consideration in the model. Experiments were conducted in this study to examine the capabilities of the cubic spline scheme, The correspondence between the numerical results and the experimental data was fair, The results were also compared with the numerical results obtained using finite difference schemes with good agreement.

关键词： numerical model cubic spline scheme,hydraulics environment pollution

Hepatic organ protection:From basic science to clinical practice

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World Journal of Gastroenterology 2010年第48期16卷 6044-6045页

作者： rene Schmidt Department of Anesthesiology and Critical Care Medicine Freiburg University Medical Center

Hepatic ischemia and reperfusion (I/R) injury during liver surgery is still the main cause of postoperative liver failure and the subsequent rise of mortality in these patients. During the last few years, a multitude of underlying mechanisms have been extensively characterized and many different protective approaches have been evaluated under experimental conditions. Some of them have already found their way into small sized clinical trials. In this Topic Highlight series of articles, we present recent insights into promising protective concepts including the regulation and optimization of hepatic blood flow, molecular mechanisms of preconditioning and pharmacological approaches with the aim of limiting hepatic I/R injury. Leading international experts present the latest experimental evidence in their fields stressing clinically relevant ideas, which are now on the edge of entering clinical practice.

关键词： Heme oxygenase-1 Hepatectomy Hepatic organ protection Ischemia/reperfusion injury Liver blood flow Liver transplantation Preconditioning

Do people communicate about their whereabouts? Investigating the relation between user-generated text messages and Foursquare check-in places

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Geo-Spatial Information Science 2018年第3期21卷 159-172页

作者： Ming Li rene Westerholt Alexander Zipf Institute of Geography Heidelberg UniversityHeidelbergGermany

The social functionality of places(***,restaurant)partly determines human behaviors and reflects a region’s functional *** descriptions of places are thus valuable to a range of studies of humans and geographic *** their potential impacts on human verbalization behaviors,one possibility is to link the functions of places to verbal representations such as users’postings in location-based social networks(LBSNs).In this study,we examine whether the heterogeneous user-generated text snippets found in LBSNs reliably reflect the semantic concepts attached with check-in *** investigate Foursquare because its available categorization hierarchy provides rich a-priori semantic knowledge about its check-in places,which enables a reliable verification of the semantic concepts identified fromuser-generated text snippets.A latent semantic analysis is conducted on a large Foursquare check-in *** results confirm that attached text messages can represent semantic concepts by demonstrating their large correspondence to the official Foursquare venue *** further elaborate the representativeness of text messages,this work also performs an investigation on the textual terms to quantify their abilities of representing semantic concepts(i.e.,representativeness),and another investigation on semantic concepts to quantify how well they can be represented by text messages(i.e.,representability).The results shed light on featured terms with strong locational characteristics,as well as on distinctive semantic concepts with potentially strong impacts on human verbalizations.

关键词： Text mining latent semantic analysis semantic concepts Foursquare location-based social network(LBSN)

Taking advantage of drug resistance, a new approach in the war on cancer

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Frontiers of Medicine 2018年第4期12卷 490-495页

作者： Liqin Wang rene Bernards Division of Molecular Carcinogenesis Oncode Institute The Netherlands Cancer Institute Plesmanlaan 121 1066 CX Amsterdam The Netherlands

Identification of the driver mutations in cancer has resulted in the development of a new category of molecularly targeted anti-cancer drugs. However, as was the case with conventional chemotherapies, the effectiveness of these drugs is limited by the emergence of drug-resistant variants. While most cancer therapies are given in combinations that are designed to avoid drug resistance, we discuss here therapeutic approaches that take advantage of the changes in cancer cells that arise upon development of drug resistance. This approach is based on notion that drug resistance comes at a fitness cost to the cancer cell that can be exploited for therapeutic benefit. We discuss the development of sequential drug therapies in which the first therapy is not given with curative intent, but to induce a major new sensitivity that can be targeted with a second drug that selectively targets the acquired vulnerability. This concept of collateral sensitivity has hitherto not been used on a large scale in the clinic and holds great promise for future cancer therapy.

关键词： cancer drug resistance genetic screens senescence targeted therapy

Alternative approaches for estimating missing climate data:application to monthly precipitation records in South- Central Chile

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Forest Ecosystems 2018年第4期5卷 390-399页

作者： Alonso Barrios Guillermo Trincado rene Garreaud Escuela de Graduados Facultad de Ctencias Forestales y Recursos Naturales Universidad Austral de ChileBox 567ValdiviaChile Departamento de Ciencias Forestales Facuitad de Ingenieria ForestalUnlversidad del Tolima Box 6299 Ibague Colombia Instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austraide ChileBox 567 ValdiviaChile Departamento de Geofistca Facultad de Ciencias Fisicas y MatematicasUniversidad de ChileSantiagoChile

Background: Over the last decades interest has grown on how climate change impacts forest resources. However,one of the main constraints is that meteorological stations are riddled with missing climatic data. This study compared five approaches for estimating monthly precipitation records: inverse distance weighting(IDW), a modification of IDW that includes elevation differences between target and neighboring stations(IDW_m), correlation coefficient weighting(CCW), multiple linear regression(MLR) and artificial neural networks(ANN).Methods: A complete series of monthly precipitation records(1995-2012) from twenty meteorological stations located in central Chile were used. Two target stations were selected and their neighboring stations, located within a radius of25 km(3 stations) and 50 km(9 stations), were identified. Cross-validation was used for evaluating the accuracy of the estimation approaches. The performance and predictive capability of the approaches were evaluated using the ratio of the root mean square error to the standard deviation of measured data(RSR), the percent bias(PBIAS), and the NashSutcliffe efficiency(NSE). For testing the main and interactive effects of the radius of influence and estimation approaches,a two-level factorial design considering the target station as the blocking factor was ***: ANN and MLR showed the best statistics for all the stations and radius of influence. However, these approaches were not significantly different with IDW_m. Inclusion of elevation differences into IDW significantly improved IDW_m estimates. In terms of precision, similar estimates were obtained when applying ANN, MLR or IDW_m, and the radius of influence had a significant influence on their estimates, we conclude that estimates based on nine neighboring stations located within a radius of 50 km are needed for completing missing monthly precipitation data in regions with complex ***: It is concluded that approaches based on ANN

关键词： Climatological data Cross-validation Artificial neural networks Multiple linear regression

Influence of the Iron Anisothermal Sintering on the Characteristic of the Hollow Cathode Discharge

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材料热处理学报 2004年第5期25卷 83-87页

作者： BRUNATTO Silvio Francisco MUZART Joel Louis rene Department of Mechanical Engineering UFPR 81531-990 Curitiba-PR BrazilDepartment of Mechanical Engineering UFSC 88040-900 Florianopolis-SC Brazil

This work studies the influence of anisothermal iron sintering process on hollow cathode discharge characteristics. Two independent cathodes form an annular discharge. The pressed cylindrical iron powder sample, acting as central cathode, was placed concentrically in the interior of an external cathode. The external cathode, machined from an AISI 310 steel bar, besides acting to confine the geometry of the plasma, can also acts as a source of alloying elements. The sample heating is a function of the ion bombardment energy and, so, of the discharge electrical parameters: current (or current density) and the effective potential applied to the cathode. Successive anisothermal sintering is performed in a same sample until the reproducibility of the electrical parameters being obtained. The heating experiments up to 1250 °C, in a gas mixture of 80% Ar + 20% H2, at pressure of 133 Pa, at flow of 2xlO"6 mV, with an inter-cathode radial space of 5.8 mm, were carried out. It was verified the metallurgical evolution of the iron sample sintering process influences the current-?0n (time switched-on of the pulse) characteristics of the discharge.

关键词：空心阴极放电等离子体焊结烧结铁溅射非等温焙烧

High-voltage direct current fault current interruption:A technology review

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High Voltage 2021年第2期6卷 171-192页

作者： rene P.P.Smeets Nadew A.Belda Innovation KEMA LabsArnhemNetherlands

This review paper describes fault current interruption principles and various high-voltage direct currrent(HVDC)circuit breaker ***,fundamentals of HVDC fault current interruption and a generic set of requirements of HVDC circuit breakers are *** critical parameters during fault current interruption are assessed using a simplified mathematical ***,the state-of-the-art of HVDC circuit breaker technologies and their application in actual HVDC multi-terminal projects is *** sub-components of HVDC circuit breakers are standard components used in a non-standard application and,hence,have to face non-standard *** of today's HVDC circuit breaker technologies consist of mechanical switching devices and metal-oxide surge arresters,which are used in an unconventional way.A critical analysis of these stresses compared to the stresses in a conventional application is ***-mendations on testing supported with examples of actual full-power‘complete’demonstration of HVDC circuit breakers up to 350 kV/20 kA are ***,the actual status of standardisation activities is presented.

关键词： fault critical hence