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Surveillance colonoscopy practice in Lynch syndrome in the Netherlands:A nationwide survey

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World journal of Gastroenterology 2007年第34期13卷 4658-4659页

作者： jan j Koornstra hans FA Vasen Department of Gastroenterology and Hepatology University Medical Centre Groningen University of Groningen Groningen The Netherlands The Netherlands Foundation for the Detection of Hereditary Tumors Department of Gastroenterology Leiden University Medical Centre Leiden The Netherlands

Lynch syndrome, or hereditary nonpolyposis colorectal cancer (HNPCC), is the most common genetic disorder predisposing to colorectal cancer. As regular colonoscopic surveillance has been shown to reduce the incidence of colorectal cancer, this strategy is recommended worldwide. Recently, several advances in colonoscopic techniques have improved detection rates of neoplasia in Lynch syndrome. In this nationwide survey, we evaluated current surveillance colonoscopy practices for Lynch syndrome in the Netherlands and the extent to which advanced techniques have been adopted in routine clinical practice.

关键词： Lynch syndrome Hereditary nonpolyposiscolorectal cancer Colonoscopy Surveillance Chromoendoscopy

AtGGM2014, an Arabidopsis gene co-expression network for functional studies

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Science China(Life Sciences) 2015年第3期58卷 276-286页

作者： MA ShiSong BOHNERT hans j DINESH-KUMAR Savithramma P Department of Plant Biology and the Genome Center College of Biological Sciences University of California Departments of Plant Biology and of Crop Sciences University of Illinois at Urbana-Champaign

Gene co-expression networks provide an important tool for systems biology studies. Using microarray data from the Array Express database, we constructed an Arabidopsis gene co-expression network, termed At GGM2014, based on the graphical Gaussian model, which contains 102,644 co-expression gene pairs among 18,068 genes. The network was grouped into 622 gene co-expression modules. These modules function in diverse house-keeping, cell cycle, development, hormone response, metabolism, and stress response pathways. We developed a tool to facilitate easy visualization of the expression patterns of these modules either in a tissue context or their regulation under different treatment conditions. The results indicate that at least six modules with tissue-specific expression pattern failed to record modular regulation under various stress conditions. This discrepancy could be best explained by the fact that experiments to study plant stress responses focused mainly on leaves and less on roots, and thus failed to recover specific regulation pattern in other tissues. Overall, the modular structures revealed by our network provide extensive information to generate testable hypotheses about diverse plant signaling pathways. At GGM2014 offers a constructive tool for plant systems biology studies.

关键词： Arabidopsis gene co-expression network graphical Gaussian model plant development stress response hormone response

Modeling slow deformation of polygonal particles using DEM

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Particuology 2008年第6期6卷 506-514页

作者： Andrés A. Pea Pedro G. Lind hans j. Herrmann Institute for Computational Physics Universitt Stuttgart Computational Physics IfB HIF E12 ETH Hnggerberg CH-8093 Zrich Switzerland Departamento de Física Universidade Federal do Ceará

We introduce two improvements in the numerical scheme to simulate collision and slow shearing of irregular particles. First, we propose an alternative approach based on simple relations to compute the frictional contact forces. The approach improves efficiency and accuracy of the Discrete Element Method （DEM） when modeling the dynamics of the granular packing. We determine the proper upper limit for the integration step in the standard numerical scheme using a wide range of material parameters. To this end, we study the kinetic energy decay in a stress controlled test between two particles. Second, we show that the usual way of defining the contact plane between two polygonal particles is, in general, not unique which leads to discontinuities in the direction of the contact plane while particles move. To solve this drawback, we introduce an accurate definition for the contact plane based on the shape of the overlap area between touching particles, which evolves continuously in time.

关键词： Granular media Discrete element method Slow deformation Contact forces

CALCULATION OF THE YOUNG'S MODULUS OF AN ADSORBED POLYMER LAYER

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Chinese journal of Polymer Science 2007年第1期25卷 95-105页

作者： Rüdiger Stark Michael Kappl hans-jürgen Butt Max-Planck-Institute for Polymer Research Ackermannweg 1055128 MainzGermany

Polymer layers adsorbed to a surface or in a confined environment often change their mechanical properties. There is even the possibility of solidification of the confined layer. To judge the stiffness of such a layer, we used the Hertz model to calculate the Young＇s modulus of the polymer layer in the confinement of AFM experiments with silicon nitride tip with a radius of curvature ofR ≈ 50 nm and a glass sphere attached to the cantilever R =5 μm. Since there is no visible indentation of the layer in the AFM experiments, the layer is either penetrated very easily, or the indentation is too small to be seen in a force curve. The latter would be the case for a polymer layer with a Young＇s modulus above 4 × 10^8 Pa in case of an experiment with a silicon nitride tip and 4×10^5 Pa in case of a glass sphere.

关键词： AFM PDMS PI Confined polymer Young's modulus Solidification.

Linking monitoring and modelling for river basin management:Danish experience with combating nutrient loadings to the aquatic environment from point and non-point sources

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Science China(Technological Sciences) 2009年第11期52卷 3335-3347页

作者： KRONVANG Brian WINDOLF jФrgen GRANT Ruth ANDERSEN hans E THODSEN hans OVESEN Niels B LARSEN SФren E National Environmental Research Institute Aarhus University VejlsФvej 25 DK-8600 Silkeborg Denmark

Nationwide monitoring of the aquatic environment was initiated in 1988 in Denmark as a means to follow the outcome of the Action Plans for nutrient pollution of the aquatic environment. Five Action Plans have been adopted by the Danish Parliament since 1985 and the nationwide monitoring programme can be used to quantify the outcome as shown by reductions in nutrient discharges from both point and non-point sources. Moreover, the empirical experience gathered from nearly 20 years of monitoring is assisting the development and calibration of models for simulation of nitrogen leaching, nitrogen removal in groundwater and surface waters and the establishment of a P-index all covering the entire land area of Denmark.

关键词： nitrogen phosphorus monitoring data point sources non-point sources models Action Plans Danish experience

Progastrin-releasing peptide and gastrin-releasing peptide receptor mRNA expression in non-tumor tissues of the human gastrointestinal tract

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World journal of Gastroenterology 2006年第16期12卷 2574-2578页

作者： hans-jürg Monstein Niclas Grahn Mikael Truedsson Bodil Ohisson Molecular Biology Laboratory-LMC University HospitalDepartment of Biomedicine and SurgeryFaculty of Health SciencesS-581 85 LinkpingSweden Department of Clinical Sciences University Hospital MalmS-205 02 MalmSweden

AIM： To investigate the expression of gastrin-releasing peptide （GRP） and GRP-receptor mRNA in non-tumor tissues of the human esophagus, gastrointestinal tract, pancreas and gallbladder using molecular biology techniques. METHODS： Poly A^＋ mRNA was isolated from total RNA extracts using an automated nucleic acid extractor and, subsequently, converted into single-stranded cDNA （sscDNA）. PCR amplifications were carried out using genespecific GRP and GRP-receptor primers. The specificity of the PCR amplicons was further confirmed by Southern blot analyses using gene-specific GRP and GRP-receptor hybridization probes. RESULTS： Expression of GRP and GRP-receptor mRNA was detected at various levels in nearly all segments of the non-tumor specimens analysed, except the gallbladder. In most of the biopsy specimens, coexpression of both GRP and GRP-receptor mRNA appeared to take place. However, expression of GRP mRNA was more prominent than was GRP-receptor mRNA. CONCLUSION： GRP and GRP-receptor mRNAs are expressed throughout the gastrointestinal tract and provides information for the future mapping and determination of its physiological importance in normal and tumor cells.

关键词： Gastrin releasing peptide (GRP) Gastrinreleasing peptide receptor (GRPR) mRNA expression Morphogenesis Gastrointestinal tract

Preface: Metamorphism and Orogenic Belts——Response from Micro-to Macro-Scale

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journal of Earth Science 2019年第6期30卷 1075-1083页

作者： Xu-Ping Li hans-Peter Schertl jürgen Reinhardt Shandong Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdao 266590China Ruhr-University Bochum Institute of GeologyMineralogy and GeophysicsD-44780 BochumGermany College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Department of Earth Sciences University of the Western CapeBellville 7535South Africa

The geological toolbox for the analysis of orogenic processes has seen substantial additions over the recent *** advances have been made in the ability to simulate geological conditions and processes by computer modeling,we have a much improved knowledge of geochemical processes(trace elements and isotopes in particular),and,last but not least,the range and versatility of micro-analytical methods and instrumentation available to us has been expanded *** latter aspect has had a particular impact on metamorphic petrology as the conventional tools to determine pressure-temperaturetime paths via rock and mineral analysis combined with isotope geochronology have generally gained in precision and accuracy through a much improved *** has moved from whole-grain analysis to spot analyses on zoned single grains while analyzing trace elements and isotopes at the same *** is therefore possible to recognize complex multi-stage orogenic events in single samples or single *** profiles in minerals provide us with time-scales of metamorphic and magmatic *** and trace elements as well as isotope profiles of mineral grains give us insight into changing ambient conditions during mineral *** special issue focuses on pressure-temperature conditions and geochronology of metamorphic rocks,isotope studies of magmatic rocks,partial melting and metasomatic processes,all with a view at tectonic implications and *** of the evidence has been gained from small-scale observation and *** field work and detailed microscopic examination remain indispensable,though,as demonstrated clearly by the"expansion"of the P-T space as applicable to crustal metamorphic processes towards extreme pressures and *** a consequence,much interest has thus focused on UHP and UHT rocks and the orogenic processes that generate *** is petrological evidence for subduction to,and subsequent exhumation fr

关键词： orogeny metasomatism UHP metamorphism UHT metamorphism geochemistry geochronology

Interference from HONO in the measurement of ambient air NO2 via photolytic conversion and quantification of NO

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journal of Environmental Sciences 2021年第9期33卷 184-193页

作者： Nicholas j.Gingerysty Charles A.Odame-Ankrah Nick jordan hans D.Osthoff Department of Chemistry University of CalgaryCalgary AB T2N 1N4Canada Global Analyzer Systems Ltd. Calgary AB T2E 7L6Canada

The reference method to quantify mixing ratios of the criteria air pollutant nitrogen dioxide(NO_(2)) is NO-O_(3) chemiluminescence(CL), in which mixing ratios of nitric oxide(NO) are measured by sampling ambient air directly, and mixing ratios of NO_(x)(= sum of NO and NO_(2))are measured by converting NO_(2) to NO using, for example, heated molybdenum catalyst or,more selectively, photolytic conversion(P-CL).In this work, the nitrous acid(HONO) interference in the measurement of NO_(2) by P-CL was *** with two photolytic NO2 converters are *** first used radiation centered at 395 nm, a wavelength region commonly utilized in *** second used light at 415 nm, where the overlap with the HONO absorption spectrum and hence its photolysis rate are *** ratios of NO_(2),NO_(x) and HONO entering and exiting the converters were quantified by Thermal Dissociation Cavity Ring-down Spectroscopy(TD-CRDS).Both converters exhibited high NO_(2) conversion efficiency(CF_(NO2);> 90%) and partial conversion of *** of CF against flow rate were consistent with photolysis frequencies of 4.2 s^(-1) and 2.9 s^(-1) for NO_(2) and 0.25 s^(-1) and 0.10 s^(-1) for HONO at 395 nm and 415 nm, *** larger than predicted from the overlap of the emission and HONO absorption *** results imply that measurements of NO2 by P-CL marginally but systematically overestimate true NO_(2) concentrations,and that this interference should be considered in environments with high HONO:NO_(2) ratios such as the marine boundary layer or in biomass burning plumes.

关键词： Photolytic conversion of NO_(2) HONO interference

Evolution and stability of holographic soliton pairs

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Chinese Science Bulletin 2006年第10期51卷 1174-1179页

作者： LIU jinsong WANG Cheng ZHANG Huilan hans j. Eichler State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China Optisches Institut Technische Universitaet Berlin Strasse des 17. Juni 135 D-10623 Berlin Germany

The dynamical evolution and the stabiity property of both bright and dark holographic solton pairs have been investigated numerically. Resultshow that mutual trapping between two beams in pair is balanceable and both ... 详细信息

关键词：空间光孤子非线性光学稳定性全息光学