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Recent result from the A2 real photon facility at MAMI

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Chinese Physics C 2009年第12期33卷 1120-1126页

作者： andreas Thomas Institut fr Kernphysik University Mainz J.-J. Becherweg 45 D-55099 Mainz Germany

The upgraded MAMI C accelerator is delivering electrons with an energy of 1558 MeV routinely. The A2 collaboration is doing experiments with energy marked polarised real photons produced via ＂Bremsstrahlung＂. Recent results from the GDh-experiment using a longitudinal polarised frozen spin target in combination with the DAPhNE detector and from the Crystal Ball experiment at MAMI are presented.

关键词： photonuclear reactions polarization phenomena in reactions polarized and other targets leptoninduced reactions

high performance computation on beam dynamics problems in high intensity compact cyclotrons

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 249-254页

作者： ADELMANN andreas Paul Scherrer Institut Villigen CH-5234 Switzerland

This paper presents the research progress in the beam dynamics problems for future high intensity compact cyclotrons by utilizing the state-of-the-art high performance computation technology. A "Start-to-Stop" model, which includes both the interaction of the internal particles of a single bunch and the mutual interaction of neighboring multiple bunches in the radial direction, is established for compact cyclotrons with multi-turn extraction. This model is then implemented in OPAL-CYCL, which is a 3D object-oriented parallel code for large scale particle simulations in cyclotrons. In addition, to meet the running requirement of parallel computation, we have constructed a small scale hPC cluster system and tested its performance. Finally, the high intensity beam dynamics problems in the 100 MeV compact cyclotron, which is being constructed at CIAE, are studied using this code and some conclusions are drawn.

关键词： compact cyclotron space charge effects parallel computation beam dynamics cluster system

Tyrosine kinase of insulin-like growth factor receptor as target for novel treatment and prevention strategies of colorectal cancer

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World Journal of Gastroenterology 2006年第35期12卷 5635-5643页

作者： Michael hpfner andreas P Sutter Alexander huether Viola Baradari hans Scherübl Charité-Universittsmedizin Berlin Campus Benjamin Franklin Medical Clinic I Gastroenterology/Infectious Diseases/ Rheumatology Berlin Germany Klinik für Gastroenterologie und Gastrointestinale Onkologie Vivantes-Klinikum Am Urban Dieffenbachstr. 1 Berlin 10967 Germany

AIM： To investigate the antineoplastic potency of the novel insulin-like growth factor 1 receptor （IGF-1R） tyrosine kinase inhibitor （TKI） NVP-AEW541 in cell lines and primary cell cultures of human colorectal cancer （CRC）. METhODS： Cells of primary colorectal carcinomas were from 8 patients. Immunostaining and crystal violet staining were used for analysis of growth factor receptor protein expression and detection of cell number changes, respectively. Cytotoxicity was determined by measuring the release of the cytoplasmic enzyme lactate dehydrogenase （LDh）. The proportion of apoptotic cells was determined by quantifying the percentage of sub-G1 （hypodiploid） cells. Cell cycle status reflected by the DNA content of the nuclei was detected by flow cytometry. RESULTS： NVP-AEW541 dose-dependently inhibited the proliferation of colorectal carcinoma cell lines and primary cell cultures by inducing apoptosis and cell cycle arrest. Apoptosis was characterized by caspase-3 activation and nuclear degradation. Cell cycle was arrested at the G1/S checkpoint. The NVP-AEW541-mediated cell cycle-related signaling involved the inactivation of Akt and extracellular signal-regulated kinase （ERK） 1/2, the upregulation of the cyclin-dependent kinase inhibitors p21^waf1/CIP1 and p27^kjp1, and the downregulation of the cell cycle promoter cyclin D1. Moreover, BAX was upregulated during NVP-AEW541-induced apoptosis, whereas Bcl-2 was downregulated. Measurement of LDh release showed that the antineoplastic effect of NVP-AEW541 was not due to general cytotoxicity of the compound. however, augmented antineoplastic effects were observed in combination treatments of NVP-AEW541 with either 5-FU, or the EGFR-antibody cetuximab, or the hMG-CoA-reductase inhibitor fluvastatin. CONCLUSION： IGF-1R-TK inhibition is a promising novel approach for either monoor combination treatment strategies of colorectal carcinoma and even for CRC chemoprevention.

关键词： Insulin-like growth factor receptor Tyrosine kinase Colorectal cancer Apoptosis Cell cycle arrest

Impact of surface phase coexistence on the development of step-free areas on Si（111）

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Frontiers of Materials Science 2015年第2期9卷 141-146页

作者： andreas FISSEL Ayan Roy ChAUDhURI Jan KRUGENER Philipp GRIBISCh h. Jorg OSTEN Institute of Electronic Materials and Devices Leibniz University Hannover Schneiderberg 32 30167 Hannover Germany

The step-flow growth condition of Si on Si（111） near the （7×7）-＂1×1＂ surface phase transition temperature Tc are analyzed within the framework of Burton- Cabrera-Frank theory. In particular, coexistence of both surface phases well below Tc and their specific influence on the step-flow growth behavior are considered. We presume that under dynamical condition of growth, the surface initially covered by only the （7×7） phase separates into domains surrounded by ＂1×1＂ areas. On such a surface, the overall supersaturation should be reduced drastically compared to a surface with only （7×7）, resulting in much larger critical terrace width for nucleation.

关键词： molecular beam epitaxy step-flow growth mode surface superstructure silicon

Liver Fat Scores for Noninvasive Diagnosis and Monitoring of Nonalcoholic Fatty Liver Disease in Epidemiological and Clinical Studies

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Journal of Clinical and Translational hepatology 2023年第5期11卷 1212-1227页

作者： Mona Reinshagen Stefan Kabisch andreas F.h.Pfeiffer Joachim Spranger Department of Endocrinology and Metabolism Campus Benjamin FranklinCharitéUniversity MedicineBerlinGermany Deutsches Zentrum für Diabetesforschung e.V. Geschäftsstelle am Helmholtz-Zentrum MünchenNeuherbergGermany

Nonalcoholic fatty liver disease(NAFLD)is strongly associated with the metabolic syndrome and type 2 diabetes and independently contributes to long-term *** often asymptomatic but reversible,it would require population-wide screening,but direct diagnostics are either too invasive(liver biopsy),costly(MRI)or depending on the examiner’s expertise(ultrasonography).hepatosteatosis is usually accommodated by features of the metabolic syndrome(***,disturbances in triglyceride and glucose metabolism),and signs of hepatocellular damage,all of which are reflected by biomarkers,which poorly predict NAFLD as single item,but provide a cheap diagnostic alternative when integrated into composite liver fat *** liver index,NAFLD LFS,and hepatic steatosis index are common and accurate indices for NAFLD prediction,but show limited accuracy for liver fat *** indices are rarely *** fibrosis scores are commonly used in clinical practice,but their mandatory reflection of fibrotic reorganization,hepatic injury or systemic sequelae reduces sensitivity for the diagnosis of simple ***-induced liver fat changes are poorly reflected by liver fat indices,depending on the intervention and its specific impact of weight loss on *** limited validity in longitudinal settings stimulates research for new ***,hepatokines,markers of cellular integrity,genetic variants but also simple and inexpensive routine parameters might be potential ***,liver fat indices lack precision for NAFLD prediction or monitoring in individual patients,but in large cohorts they may substitute nonexistent imaging data and serve as a compound biomarker of metabolic syndrome and its cardiometabolic sequelae.

关键词： NAFLD Liver fat indices Fatty liver index Prediction Dietary intervention

The fate of the herbicide propanil in plants of the littoral zone of the Three Gorges Reservoir(TGR),China

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Journal of Environmental Sciences 2016年第10期28卷 24-33页

作者： Zhongli Chen andreas Schaffer Institute for Environmental Research(Biology V) RWTH Aachen UniversityAachen 52074Germany. Nanjing University School of the Environment Nanjing 210023China Chongqing University College of Resource and Eavironmental ScienceChongqing 400030China

The anti-seasonal hydrology with 30 m water fluctuations in the Three Gorges Reservoir(TGR)of China attracts growing environmental and ecological *** investigated the biotransformation of the herbicide propanil in plants dominating in the littoral zone of the TGR by applying the 14C-ring-labeled herbicide into non-aseptic hydroponic plant systems(Cynodon dactylon,Nelumbo nucifera and Bidens pilosa),aseptic plants(Lemna minor and Lemna gibba)and cell suspension cultures(*** and ***).(1)Propanil absorbed in plants of the hydroponic systems was(12.46±1.63)%of applied radioactivity(AR)(***),(52.36±6.38)%(***)and(76.55±6.07)%(***),*** 14C-residues in the plant extractable fractions and the corresponding media were confirmed by radio-Thin Layer Chromatography(TLC),radio-high Performance Liquid Chromatography(hPLC)and Gas Chromatography-Electron Ionization Mass Spectrometry(GC-EIMS)as propanil,3,4-dichloroaniline(DCA)and N-(3,4-dichlorophenyl)-β-D-glucopyranosylamine(Glu-DCA).(2)About 8%of AR was taken up by both aseptic plants,from which 7.0%of AR was extracted and identified also as propanfl,DCA and Glu-DCA.(3)Concerning cell suspension cultures,(39.22±9.39)%of AR was absorbed by *** after 72 hr,whereas the accumulated 14C-propanil by *** cell suspension culture amounted to(65.04±1.72)%after 7 *** identified compounds in cell cultures are consistent with those in the tested *** of the pesticide residues in the intact plants were un-extractable,which are recognized as the end of the detoxificafion *** therefore consider these plants as suitable for the phytoremediation of the herbicide propanil in the TGR region.

关键词： Three Gorges Reservoir(TGR) Propanil Plant degradation Non-extractable residues(NER)

REGENERATION FACTOR 1, a peptide boost for wound healing and plant biotechnology

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Molecular Plant 2024年第9期17卷 1333-1334页

作者： andreas Schaller University of hohenheim Department of Plant Physiology and Biochemistry70593 StuttgartGermany

Plants respond to wounding such as caused by insect herbivores by activating their defenses and thus increasing their resistance against attacking pests and opportunistic pathogens(howe and Schaller,2008).The phenomenon was first described more than 50 years ago by Green and Ryan,who reported that wounding triggers tomato and potato plants to produce proteinase inhibitors that inhibit digestive proteases in the gut of leaf-eating insects to starve them of nutrients(Green and Ryan,1972).They also observed that the accumulation of proteinase inhibitors is not restricted to wounded leaves but occurs throughout the aerial parts of the *** search for a chemical signal that is released locally in response to wounding and that mediates systemic activation of defense gene expression led to the identification of systemin,the first ever peptide with hormonelike activity in plants(Pearce et al.,1991).These seminal findings sparked much research into systemic defense responses and peptide signaling in general,and we know now that systemin is one of many phytocytokines that regulate a multitude of immune responses in plants(Schilmiller and howe,2005;Gust et al.,2017).

关键词： wound activation defense

Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： andreas Döpp Ludwig-Maximilian-Universität München Am Coulombwall 185748GarchingGermany Max Planck Institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

Characteristics of elution profile in radial chromatography under linear conditions

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Science China Chemistry 2005年第4期48卷 352-360页

作者： andreas Seidel-Morgenstern Max-Planck-Institut für Dynamik Komplexer Technischer Systeme 39106MagdeburgGermany

Based on the mass balance equations of solute transfer in the radial chroma-tographic column,the theoretical expression to describe the column efficiency and shape of elu-tion profile is obtained under linear isotherm ***,the tendency for the variation of column efficiency and symmetry of peak profile is systematically *** results showed that in radial chromatography the relationship between the column efficiency and volumetric flow rate is similar with that relationship in axial chromatography;relatively high column efficiency still can be obtained under high flow rate in radial *** the increase of retention factor of solutes and injection time,the column efficiency decreases *** effect of column diameter and column length on the column efficiency interfere with each *** is more advantageous to increase the column efficiency by applying columns with larger column diameter and shorter column *** to the discussion of the effect of diffusion on the column efficiency,radial chromatography is proved to be suitable for the separation of samples with relatively high diffusion coefficient,which predicts its obvious advantage in the preparative separation of samples such as proteins and DNA.

关键词： radial chromatography, column efficiency, elution profile, symmetry.