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Thorium/uranium mixed oxide nanocrystals： Synthesis, structural characterization and magnetic properties

Nano Research 2014年第1期7卷 119-131页

作者： Damien hudry Jean-Christophe Griveau Christos Apostolidis Olaf Walter Eric Colineau gert Rasmussen Di wang Venkata Sai Kiran Chakravadhaluna Eglantine Courtois Christian Kubel Daniel Meyer European Commission: Joint Research Centre Institute for Transuranium Elements P. O. Box 2340 76125 Karlsruhe Germany Karlsruhe Institute of Technology Institute ofNanotechnology Hermann-von-Helmholtz-Platz1 76344 Eggenstein-Leopoldshafen Germany Karlsruhe Institute of Technology Karlsruhe Nano Micro Facility Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany helmholtz Institute UIm for Electrochemical Energy Storage Albert-Einstein-Allee 11 89069 UIm Germany Institut de Chimie Separative de Marcoule UMR 5257 BP 1717 1 30207 Bagnols sur Ceze Cedex France Karlsruhe Institute of Technology Institute for Catalysis Research and Technology Hermann-von-Helmholtz-Platz 1 76344 Eggenstein Leopoldshafen Germany

One of the primary aims of the actinide community within nanoscience is to develop a good understanding similar to what is currently the case for stable elements. As a consequence, efficient, reliable and versatile synthesis techniques dedicated to the formation of new actinide-based nano-objects （e.g., nanocrystals） are necessary. hence, a ＂library＂ dedicated to the preparation of various actinidebased nanoscale building blocks is currently being developed. Nanoscale building blocks with tunable sizes, shapes and compositions are of prime importance. So far, the non-aqueous synthesis method in highly coordinating organic media is the only approach which has demonstrated the capability to provide size and shape control of actinide-based nanocrystals （both for thorium and uranium, and recently extended to neptunium and plutonium）. In this paper, we demonstrate that the non-aqueous approach is also well adapted to control the chemical composition of the nanocrystals obtained when mixing two different actinides. Indeed, the controlled hot co-injection of thorium acetylacetonate and uranyl acetate （together with additional capping agents） into benzyl ether can be used to synthesize thorium/uranium mixed oxide nanocrystals covering the full compositional spectrum. Additionally, we found that both size and shape are modified as a function of the thorium：uranium ratio. Finally, the magnetic properties of the different thorium/uranium mixed oxide nanocrystals were investigated. Contrary to several reports, we did not observe any ferromagnetic behavior. As a consequence, ferromagnetism cannot be described as a universal feature of nanocrystals of non-magnetic oxides as recently claimed in the literature.

关键词： thorium uranium mixed oxide non-aqueous synthesis nanoparticle nanocrystal magnetism

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A Receiver Model for Ultrasonic Ray Tracing in an Inhomogeneous Anisotropic Weld

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Journal of Modern Physics 2014年第13期5卷 1186-1201页

作者： Q. Liu gert Persson hakan Wirdelius Department of Materials and Manufacturing Technology Chalmers University of Technology Goteborg Sweden

In this paper, a receiver model for ultrasonic ray tracing simulation is described. This is a complementary part of an existing simulation model and is the next step towards a numerical solution to the inverse problem and thus a NDT methodology for characterization of the dendrite orientation in a weld. The establishment of the receiver model is based on the electromechanical reciprocity principle. A concise retrospect of the weld model and the 2D model is made. The reciprocity principle is applied in an original way to handle the model problem including the back wall. Experimental qualitative validations for both P and SV waves on a specific weld are also made for C-scans included in this paper. Two different cases are studied. The first is a direct incidence of an ultrasonic ray towards the weld, and the second is a reflection from the back surface in the base material followed by an incidence to the weld. Even though mode-converted rays are excluded in the simulations, both the P and SV probe-models show the same behavior as the experimental results. The qualitative validation though reveals that it even if a thorough time-gating of received information would enable exclusion of mode-conversion in the model, inaccuracy of experimental results is affecting the evaluation of the weld model.

关键词： Ultrasonic Receiver Model Reciprocity Principle 2D Ray Tracing

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国外信息系统审计规范、国家文化差异与制度移植

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审计研究 2012年第5期 14-21,35页

作者：张文秀 gert Van Der Pijl 南京审计学院国际审计学院荷兰鹿特丹伊拉斯姆斯大学经济学院

我国在借鉴国外信息系统审计规范的过程中需注意国家文化差异对制度移植的影响。本文选取当前国际上比较典型的可用于信息系统审计的标准、框架和指南进行综合比较,用hofstede的国家文化模型分析我国与这些制订规范国家的文化差异及其... 详细信息

我国在借鉴国外信息系统审计规范的过程中需注意国家文化差异对制度移植的影响。本文选取当前国际上比较典型的可用于信息系统审计的标准、框架和指南进行综合比较,用hofstede的国家文化模型分析我国与这些制订规范国家的文化差异及其对信息系统审计规范的影响,并探讨在信息系统审计规范移植过程中超越简单的制度移植,考虑国家文化特点进行规范的选择、完善与实施策略。

关键词：信息系统审计审计准则准则比较文化差异制度移植

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Uptake of citrate-coated iron oxide nanoparticles into atherosclerotic lesions in mice occurs via accelerated transcytosis through plaque endothelial cells

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Nano Research 2016年第11期9卷 3437-3452页

作者： Wolfram C. Poller Evelyn Ramberger Philipp Boehm-Sturm Susanne Mueller Konstantin Moller Norbert Lowa Frank Wiekhorst Susanne Wagner Matthias Taupitz Eyk Schellenberger gert Baumann Karl Stangl Verena Stangl Antje Ludwig Medizinische Klinik mit Schwerpunkt Kardiologie und Angiologie Charite-Universitatsmedizin Berlin Campus Mitte Chariteplatz 1 10117 Berlin Germany Abteilung fur Experimentelle Neurologie Center for Stroke Research Charite-Universitatsmedizin Berlin Chariteplatz 1 10117 Berlin Germany Charite Core Facility '7 T experimental MRIs' Charite-Universitatsmedizin Berlin Chariteplatz 1 10117 Berlin Germany Physikalisch-Technische Bundesanstalt Abbestr. 2-12 10587Berlin Germany Institut fur Radiologie Charite-Universitatsmedizin Berlin Campus Mitte Charit@platz 1 10117 Berlin Germany DZhK (German Centre for Cardiovascular Research) partner site Berlin 10115 Berlin Germany Berlin Institute of health (BIh) 10117 Berlin Germany

Very small superparamagnetic iron oxide nanoparticles （VSOPs） rapidly accumulate in atherosclerotic lesions, thereby enabling plaque visualization by magnetic resonance imaging （MRI）. This study was performed to identify the uptake mechanisms of VSOPs into atherosclerotic plaques. Low-density lipoprotein receptor-deficient （LDLR^-/-） mice with advanced atherosclerosis were analyzed using MRI and transmission electron microscopy （TEM） at various time points after intravenous administration of VSOPs. Post-mortem MRI detected VSOP labeling of atherosclerotic plaques 10 min after injection, and the signal increased over the first 3 h. TEM revealed that the intensive plaque labeling was mediated by accelerated transcytosis of VSOPs through endothelial cells overlaying atherosclerotic lesions. Experiments with endocytosis inhibitors and small interfering RNA （siRNA） revealed a dynamin-dependent mechanism involving both clathrin- and caveolin-mediated processes. In cell culture experiments, endothelial VSOP uptake was enhanced under proatherogenic flow and TNFα stimulation, conditions that are both present in plaque areas. Our study demonstrates that VSOPs enable non-invasive MRI assessment of accelerated endothelial transcytosis, an important pathomechanism in atherosclerotic plaque formation.

关键词： atherosclerosis,unstable plaques,magnetic resonanceimaging decreased endothelial barrier function,superparamagnetic ironoxide nanoparticles

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Window Effect in the Power Spectrum Analysis of a Galaxy Redshift Survey

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International Journal of Astronomy and Astrophysics 2013年第3期3卷 243-256页

作者： Takahiro Sato gert hutsi Gen Nakamura Kazuhiro Yamamoto Graduate School of Physical Sciences Hiroshima UniversityHigashi-HiroshimaJapan Tartu Observatory TorevereEstonia

We investigate the effect of the window function on the multipole power spectrum in two different ways. First, we consider the convolved power spectrum including the window effect, which is obtained by following the familiar (FKP) method developed by Feldman, Kaiser and Peacock. We show how the convolved multipole power spectrum is related to the original power spectrum, using the multipole moments of the window function. Second, we investigate the deconvolved power spectrum, which is obtained by using the Fourier deconvolution theorem. In the second approach, we measure the multipole power spectrum deconvolved from the window effect. We demonstrate how to deal with the window effect in these two approaches, applying them to the Sloan Digital Sky Survey (SDSS) luminous red galaxy (LRG) sample.

关键词： Cosmology Large-Scale Structure of Universe

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Value of macrobiopsies and transanal endoscopic microsurgery in the histological work-up of rectal neoplasms:A retrospective study

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World Journal of Gastrointestinal Oncology 2017年第6期9卷 251-256页

作者： Guus MJ Bokkerink gert-Jan van der Wilt Dirk de Jong han hJM van Krieken Robert P Bleichrodt Johannes hW de Wilt Andreas JA Bremers Department of Surgery Radboud University Nijmegen Medical Center Department of health Evidence Radboud University Nijmegen Medical Center Department of Gastroenterology Radboud Uni-versity Nijmegen Medical Center Department of Pathology Radboud University Nijmegen Medical Center Department of of Surgery Saint Francis Hospital

To evaluate a step up approach: Taking macrobiopsies and performing excision biopsies in patients with suspected rectal cancer in which biopsies taken though the flexible endoscope showed benign histology. METhODSPatients with a rectal neoplasm who underwent flexible endoscopy and biopsies were included. In case of benign biopsies rigid rectoscopy and macrobiopsies were employed. If this failed to prove malignancy, transanal endoscopic microsurgery (TEM) was used in a final effort to establish a certain preoperative diagnosis. The preoperative results were compared with the findings after surgical excision and follow up to calculate the reliability of this algorithm. RESULTSOne hundred and thirty-two patients were included. One hundred and ten patients with a carcinoma and 22 with an adenoma. Seventy-five of 110 carcinomas were proven malignant after flexible endoscopy. With the addition of rigid endoscopy and taking of macrobiopsies, this number increased to 89. Performing TEM excision biopsies further enlarged the number of proven malignancies to 100. CONCLUSIONThe step-up approach includes taking macrobiopsies through the rigid rectoscope and performing excision biopsies using transanal endoscopic microsurgery in addition to flexible endoscopy. This approach, reduced the number of missed preoperative malignant diagnoses from 32% to 9%.

关键词： Rectal cancer histology Biopsy Macrobiopsy Transanal endoscopic microsurgery Sampling error

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Impact of black cherry on pedunculate oak vitality in mixed forests:Balancing benefits and concerns

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Forest Ecosystems 2023年第6期10卷 690-699页

作者： Ellen Desie Bart Muys Jan den Ouden Bart Nyssen Rita Sousa-Silva Leon van den Berg Arnold van den Burg gert-Jan van Duinen Koenraad Van Meerbeek Maaike Weijters Karen Vancampenhout Division Forest Nature and LandscapeKU Leuven Campus GeelKleinhoefstraat 4B-2240 GeelBelgium Division Forest Nature and LandscapeKU LeuvenCelestijnenlaan 200EBox 2411B-3001 LeuvenBelgium KU Leuven Plant Institute B-3001 LeuvenBelgium Forest Ecology and Management Group Wageningen UniversityP.O.Box 47Wageningenthe Netherlands Bosgroep Zuid-Nederland Huisvenseweg 145591 VD Heezethe Netherlands Young Academy for Sustainability Research University of Freiburg79104 Freiburg im BreisgauGermany Aquatic Ecology&Environmental Biology Radboud University NijmegenHeyendaalseweg 1356525 AJ Nijmegenthe Netherlands Biosphere/Zoological Museum Netherlands Onderlangs 176731 BK Otterlothe Netherlands Stichting Bargerveen Toernooiveld 16525 ED Nijmegenthe Netherlands B-WARE Research Centre/Radboud University Nijmegen Toernooiveld 16525 ED Nijmegenthe Netherlands

The vitality of European forests continues to decline due to new pests and diseases,climate-change related disturbances and high loads of atmospheric nitrogen *** soil health is a major factor underpinning the low vitality of West-European *** tree species with soil ameliorative traits is proposed as an avenue to counteract soil acidification and improve overall forest *** we evaluate the impact of black cherry(Prunus serotina Ehrh.),a known rich litter species,on the vitality of neighboring pedunculate oak(Quercus robur L.)in ten mixed forests on sand in Germany,Belgium and the *** found that black cherry admixture increases foliar N and P to a surplus whereas it causes deficiencies in foliar Mg,thereby resulting in an overall negative effect on oak foliar nutrient ***,defoliation of oak leaves by herbivory decreases with the proximity of black *** structural equation modelling(SEM),we tested the hypothesized‘improved soil health’*** analyses showed that black cherry admixture leads to lower accumulation in the humus layer,resulting in higher soil base saturation which has a positive effect on foliar Ca yet a negative effect on total ***,the SEM illustrated that herbivory of oak leaves decreases when black cherry is admixed,both via dilution and improved soil *** effects of black cherry on oak vitality via“improved soil health”in our SEM are however small in comparison to direct ***,our study showed that the combined positive and negative impacts of black cherry on oak vitality are limited,which tempers the potential benefits of using the rich litter species to counteract oak decline via improved soil health–yet,the concern of black cherry as an invasive alien species negatively affecting the vitality of mature pedunculate oak trees may also be exaggerated.

关键词： Rich litter species Black cherry Nutrient cycling Insect herbivory Dilution effect humus type Pedunculate oak Plant-soil interaction

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Species-specific,pan-European diameter increment models based on data of 2.3 million trees

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Forest Ecosystems 2018年第3期5卷 277-295页

作者： Mart-Jan Schelhaas Geerten M hengeveld Nanny heidema Esther Thurig Brigitte Rohner Giorgio Vacchiano Jordi Vayreda John Redmond Jaroslaw Socha Jonas Fridman Stein Tomter heino Polley Susana Barreiro gert-Jan Nabuurs Wageningen University and Research Wageningen Environmental Research(WENR)Droevendaalsesteeg 36708PB WageningenThe Netherlands Wageningen University and Research BiometrisDroevendaalsesteeg 16708PB WageningenThe Netherlands Wageningen University and Research Forest and Nature Conservation Policy GroupDroevendaalsesteeg 36708PB WageningenThe Netherlands Swiss Federal Institute for Forest Snow and Landscape Research WSLResource AnalysisZuercherstrasse 111CH-8903 BirmensdorfSwitzerland European Commission Joint Research CentreDirectorate DSustainable Resources-Bio-Economy UnitIspraItaly CREAF 08193 Cerdanyola del VallesSpain Univ Autonoma Barcelona 08193 Cerdanyola del VallesSpain Forest Service Department of AgricultureFood and the MarineJohnstown Castle EstateCo.WexfordIreland Department of Biometry and Forest Productivity Institute of Forest Resources ManagementFaculty of ForestryUniversity of Agriculture in KrakowAI.29Listopada 4631-425CracowPoland Swedish University of Agricultural Sciences (SLU) 90183 UmeaSweden Norwegian Institute of Bioeconomy Research P.O.Box 115N-143 1AsNorway Thunen Institute Institute of Forest EcosystemsAlfred-Mo1ler-Strabe 1Haus41/4216225 EberswaldeGermany Forest Research Centre (CEF) Instituto Superior de AgronomiaUniversidade de LisboaTapada da Ajuda1349-017Lisbon.Portugal Wageningen University and Research Forest Ecology and Forest Management GroupDroevendaalsesteeg 36708PBWageningenThe Netherlands

Background: Over the last decades, many forest simulators have been developed for the forests of individual European countries. The underlying growth models are usually based on national datasets of varying size, obtained from National Forest Inventories or from long-term research plots. Many of these models include country-and location-specific predictors, such as site quality indices that may aggregate climate, soil properties and topography effects. Consequently, it is not sensible to compare such models among countries, and it is often impossible to apply models outside the region or country they were developed for. however, there is a clear need for more generically applicable but still locally accurate and climate sensitive simulators at the European scale, which requires the development of models that are applicable across the European continent. The purpose of this study is to develop tree diameter increment models that are applicable at the European scale, but still locally accurate. We compiled and used a dataset of diameter increment observations of over 2.3 million trees from 10 National Forest Inventories in Europe and a set of 99 potential explanatory variables covering forest structure, weather, climate, soil and nutrient ***: Diameter increment models are presented for 20 species/species groups. Selection of explanatory variables was done using a combination of forward and backward selection methods. The explained variance ranged from10% to 53% depending on the species. Variables related to forest structure(basal area of the stand and relative size of the tree) contributed most to the explained variance, but environmental variables were important to account for spatial patterns. The type of environmental variables included differed greatly among ***: The presented diameter increment models are the first of their kind that are applicable at the European scale. This is an important step towards the development of a new ge

关键词： European forests Diameter increment model Climate change Growth modelling National forest inventory

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Ultra-fast Maize （Zea mays L.） hybrid Growth Response to Plant Population Density

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Journal of Agricultural Science and Technology(B) 2013年第5期3卷 334-343页

作者： Gobeze Loha Yada gert Michael Ceronio Leon Daniel Van Rensburg Department of Soil Crop and Climate Sciences P.O. Box 339 University of the Free State Bloemfontein South Africa Awassa Agricultural Research Center P.O. Box 06 Awassa Ethiopia

Current arable land and increasing food demand necessitates the practice of double and multiple cropping systems with inclusion of ultra-fast maize hybrids, which are characterized by smaller size, fewer leaves per plant, lower leaf area and fewer self-shading problems, under irrigation. In this context, a field experiment was conducted for two successive cropping seasons 2008/2009 to 2009/2010 at Kenilworth Experimental Station to evaluate the effect of row spacings and plant density on growth. Three row spacing （0.225, 0.45 and 0.90 m） and five plant densities （5, 7.5, 10, 12.5 and 15 plants m^-2） were used. Treatments were combined in a factorial combination and laid out in a completely randomized design with replications consisting of five single plants randomly selected from each treatment for destructive sampling. Growth factors reacted differently to row spacing by plant density. At crop establishment, growth indicators were not significantly affected by either main effects or a combination thereof. however, at the end of the vegetative phase, almost all growth indicators reached a maximum and were significantly affected by treatment interactions. Growth analysis showed that there was an interaction effect of row spacing by plant density on plant height, dry matter （DM） accumulation, leaf area index （LAI）, crop growth rate （CGR） and net assimilation rate （NAR） of maize. Therefore, the current investigation demonstrated that a row spacing of 0.45 m or 0.90 m with a plant density of 10 plants m^-2 was optimum for the selected ultra-fast maize hybrid under irrigation.

关键词： Maize irrigation plant population yield row spacing

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Can inhibin-B predict the outcome of microsurgical epididymal sperm aspiration in patients with suspected primary obstructive azoospermia？

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Asian Journal of Andrology 2007年第3期9卷 382-387页

作者： Marij Smit gert R. Dohle Mark F. Wildhagen Rob F. A. Weber Andrology Unit of the Department of Urology Erasmus MC 3000 CA Rotterdam the Netherlands Department of Urology and Gynecology Erasmus MC 3000 CA Rotterdam the Netherlands

Aim： To evaluate whether inhibin-B can predict the outcome of a microsurgical epidymal sperm aspiration （MESA） procedure in patients with suspected primary obstructive azoospermia （OA） and if inhibin-B can replace testicular biopsy in the diagnostic work-up of these patients. Methods： Inhibin-B levels and testicular biopsy scores were related to the outcome of MESA in 43 patients with suspected primary OA. MESA was considered to be successful when epididymal sperm could be identified during the procedure. Results： Spermatozoa were present in the epididymal aspirate in 28 out of the 43 patients （65%）. lnhibin-B values were not significantly different in patients with successful or unsuccessful MESA. The modified Johnsen score, however, was significantly lower in patients with unsuccessful MESA （P = 0.003）. A rete testis obstruction or epididymal malfunctioning was found in 15% of patients with suspected primary OA, reflected by unsuccessful MESA despite normal inhibin-B levels and normal testicular histology. Conclusion： Inhibin-B cannot replace testicular biopsy as a diagnostic tool in the work-up of patients with suspected primary OA. Testicular biopsy is useful in identifying patients with spermatogenic arrest, who might have normal inhibin-B values.

关键词： Inhibin B male infertility microsurgical epididymal sperm aspiration primary obstructive azoospermia

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