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Asymptomatic pancreatic lesions: New insights and clinical implications

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World Journal of Gastroenterology 2012年第33期18卷 4474-4477页

作者： Martin Loos Christoph W Michalski Jrg Kleeff Department of Surgery Klinikum rechts der Isar Technische Universitt München 81675 München Germany

Despite great efforts in experimental and clinical research, the prognosis of pancreatic cancer (PC) has not changed significantly for decades. Detection of pre-invasive lesions or early-stage PC with small resectable cancers in asymptomatic individuals remains one of the most promising approaches to substantially improve the overall outcome of PC. Therefore, screening programs have been proposed to identify curable lesions especially in individuals with a familial or genetic predisposition for PC. In this regard, Canto et al recently contributed an important article comparing computed tomography, magnetic resonance imaging, and endoscopic ultrasound for the screening of 216 asymptomatic high-risk individuals (HRI). Pancreatic lesions were detected in 92 of 216 asymptomatic HRI (42.6%). The high diagnostic yield in this study raises several questions that need to be answered of which two will be discussed in detail in this commentary: First: which imaging test should be performed? Second and most importantly: what are we doing with incidentally detected pancreatic lesions? Which ones can be observed and which ones need to be resected?

关键词： Pancreatic cancer Early-stage pancreatic cancer Asymptomatic high-risk individuals Preinvasive pancreatic lesions Cystic pancreatic tumors Screening Computed tomography Magnetic resonance imaging Endoscopic ultrasound

Cast iron-a predictable material

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China Foundry 2011年第1期8卷 51-61页

作者： Jrg C.Sturm Guido Busch MAGMA Gieβereitechnologie GmbH

High strength compacted graphite iron (CGI) or alloyed cast iron components are substituting previously used non-ferrous castings in automotive power train *** mechanical engineering industry has recognized the value in substituting forged or welded structures with stiff and light-weight cast iron *** products such as wind turbines have opened new markets for an entire suite of highly reliable ductile iron cast *** the last 20 years,casting process simulation has developed from predicting hot spots and solidification to an integral assessment tool for foundries for the entire manufacturing route of *** support of the feeding related layout of the casting is still one of the most important duties for casting process *** on the alloy poured,different feeding behaviors and self-feeding capabilities need to be considered to provide a defect free ***,it is not enough to base the prediction of shrinkage defects solely on hot spots derived from temperature *** be able to quantitatively predict these defects,solidification simulation had to be combined with density and mass transport calculations,in order to evaluate the impact of the solidification morphology on the feeding behavior as well as to consider alloy dependent feeding *** cast iron foundries,the use of casting process simulation has become an important instrument to predict the robustness and reliability of their processes,especially since the influence of alloying elements,melting practice and metallurgy need to be considered to quantify the special shrinkage and solidification behavior of cast *** allows the prediction of local structures,phases and ultimately the local mechanical properties of cast irons,to asses casting quality in the foundry but also to make use of this quantitative information during design of the *** quality issues related to thermally driven stresses in castings are also gaining inc

关键词： casting process simulation cast iron defects casting performance development

A machine learning approach to model solute grain boundary segregation

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npj Computational Materials 2018年第1期4卷 130-137页

作者： Liam Huber Raheleh Hadian Blazej Grabowski Jörg Neugebauer Max-Planck-Institut für Eisenforschung GmbH D-40237 DüsseldorfGermany

Even minute amounts of one solute atom per one million bulk atoms may give rise to qualitative changes in the mechanical response and fracture resistance of modern structural *** changes are commonly related to enrichment by several orders of magnitude of the solutes at structural defects in the host *** underlying concept—segregation—is thus fundamental in materials *** include it in modern strategies of materials design,accurate and realistic computational modelling tools are ***,the enormous number of defect configurations as well as sites solutes can occupy requires models which rely on severe *** the present study we combine a high-throughput study containing more than 1 million data points with machine learning to derive a computationally highly efficient framework which opens the opportunity to model this important mechanism on a routine basis.

关键词： grain solute boundary

A user perspective on future cloud-based services for Big Earth data

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International Journal of Digital Earth 2021年第12期14卷 1758-1774页

作者： Julia Wagemann Stephan Siemen Bernhard Seeger Jörg Bendix Laboratory of Climatology and Remote Sensing(LCRS) Faculty of GeographyUniversity of Marburg Forecast Department European Centre for Medium-Range Weather Forecasts(ECMWF) Department of Mathematics and Computer Science University of Marburg

Cloud-based services introduce a paradigm shift in how users access,process and analyse Big Earth data.A key challenge is to align the current state of how users access,process and analyse the data with trends and roadmaps large data organisations *** addition,due to the increased availability of open data,a more diverse user base wants to take advantage of Earth science data leading to new user *** run a web-based survey among Big Earth data users to better understand the motivation to migrate to cloud-based services as well as the challenges and opportunities that might *** show an overall interest in moving to cloud-based services but air an insufficient literacy in cloud systems and a lack of trust due to security concerns and opacity of emerging *** gaps demand efforts on three ***,cloud services shall be targeted at intermediate users instead of policy-and decision-makers and over-engineered systems with a high level of abstraction should be ***,more substantial capacity-building efforts are required to decrease the existing gap in cloud skills and ***,a cloud certification mechanism could help in building up overall trust in cloud-based services.

关键词： User requirements cloudbased services Big Earth data open data

A CONVENIENT AND EFFICIENT SYNTHESIS OF BIS-IMIDAZOLES

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Chinese Chemical Letters 1996年第4期7卷 321-324页

作者： Zhou, CH Guo, SJ Xie, rg Zhao, HM SICHUAN UNION UNIV FAC SCIDEPT CHEMCHENGDU 610064PEOPLES R CHINA

A simpler convenient and high-yield preparation for bis-imidazoles, which have a wide range of applications, from imidazole and dibromides in the presence of strong base is reported.

关键词： METAL

Analysis of arch dam deformations

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Frontiers of Structural and Civil Engineering 2010年第1期4卷 102-108页

作者： franz PERNER Pius OBERNHUBER Verbund-Austrian Hydro Power AG ViennaAustria

Predicting“regular”dam deformations for prevailing conditions and comparing them with observed deformations is an essential part of dam *** many cases prediction and comparison are carried out automatically and an alarm is triggered in the case of larger *** main contributors to the deformations of arch dams are water loading and the fluctuation of concrete *** general,the deformations exhibit an instantaneous elastic part,a time dependent reversible part and an irreversible *** of dam deformations can be based on deterministic models,purely statistical models or so-called hybrid models,which are a combination of the first *** models rely on static analyses,statistical models on the statistical analysis of previous deformation *** annual reservoirs,both water loading and temperature vary in cycles over a period of one year and it is extremely difficult to identify the various factors contributing to an observed *** is particularly true for time-dependent reversible displacements due to the water loading and the portion caused by temperature *** present article deals with the analysis of arch dam deformations based on hybrid *** attention is given to the analysis of the deformations due to temperature fluctuation and to the long-term *** proposed procedure is employed for the analysis of the deformations of the 186 m high Zillergruendl arch dam.

关键词： arch dam analysis Zillergruendl concrete temperature hybrid model

Recent weakening of seasonal temperature difference in East Asia beyond the historical range of variability since the 14th century

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Science China Earth Sciences 2023年第5期66卷 1133-1146页

作者： Jianglin WANG Bao YANG Zhiyuan WANG Jürg LUTERBACHER Fredrik Charpentier LJUNGQVIST Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China School of Geography and Ocean Science Nanjing UniversityNanjing210023China College of Geography and Environmental Science Zhejiang Normal UniversityJinhua321004China Science and Innovation Department World Meteorological Organization(WMO)Geneva1211Switzerland Department of History Stockholm UniversityStockholm10691Sweden Bolin Centre for Climate Research Stockholm UniversityStockholm10691Sweden Swedish Collegium for Advanced Study LinneanumThunbergsvägen 2Uppsala75238Sweden

Seasonal differences of temperature are crucial components of the Earth's climate ***,the relatively short observational record,especially for East Asia,has limited progress in understanding seasonal *** this study,we identify ten tree-ring chronologies separately correlated with local winter(December-February)temperatures and twelve different tree-ring chronologies separately correlated with summer(June-August)temperatures across East *** these discrete seasonal tree-ring chronologies,we develop two independent winter and summer temperature reconstructions covering the period 1376-1995 CE for East Asia,and compare them with model *** reconstructions show a more significant volcanic cooling and earlier onset of modern warming in summer than in *** reconstructed summer-minus-winter temperature decreased since as early as the late 19th century,which has driven the current state of seasonal temperature difference to out of the natural variability since the *** models could generally reproduce the variability and trends in seasonal reconstructions,but might largely underestimate seasonal differences due to the fact that seasonal expressions on external forcing and modes of internal variability are too *** study highlights the importance of using proxy-based seasonal reconstructions to evaluate the performance of climate models,and implies a substantial weakening of seasonal temperature differences in the future.

关键词： Seasonal temperature differences Temperature reconstruction East Asia Tree rings Recent warming

The Role of the European Pharmacopoeia(Ph Eur)in Quality Control of Traditional Chinese Herbal Medicine in European Member States

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World Journal of Traditional Chinese Medicine 2015年第1期1卷 5-15页

作者： Mei Wang Gerhard franz Sino-Dutch Centre for Preventive and Personalised Medicine/SU BioMedicine University of Regensburg Department of Pharmacy

In order to assure the safety and efficacy of the Chinese Medicines in Europe, the quality of TCM herbals should be guaranteed so that they can be freely imported in the European Union and other Western European Countries which are signatories of the European Pharmacopoeia Convention. Consequently, new Ph Eur TCM herbal drug Monographs should be elaborated, based on preexisting Monographs in the Chinese Pharmacopoeia(Ch P) *** a program has been inaugurated in 2005 by the Ph Eur Groups of Experts 13 A and B(Phytochemistry). Since then good progress has been made, elaborating of about one third of the originally proposed 100 TCM herbals being identified as important monographs for the European Market. Taking into account the many challenges still laying ahead, the establishment of a specialized Working Party(WP) on TCM with specialists and experts from many EU Member States has been decided by the Ph Eur Commission in 2008 which is highly active ever since in the examination and elaboration of new TCM herbal drug monographs, primarily to assure the safety of the European patient and further to provide quality parameters extremely important for all registration and licensing procedures of the respective National Authorities all over *** paper is a survey of results and difficulties obtained so far which has been encountered meanwhile in the elaboration process by the Ph Eur TCM WP of these monographs and will discuss these in detail. Moreover the role of Ph Eur TCM monographs in the European community is addressed.

关键词： European Pharmacopeia(Ph Eur) Chinese Pharmacopoeia(ChP) Traditional Chinese Medicine(TCM) TCM monographs herbal drugs and quality control

PROSPECTS AND NEW PROBLEMS OF SEDIMENT RESEARCH

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International Journal of Sediment Research 1997年第1期12卷 1-15页

作者： Wang, Zhaoyin Lin, Bingnan Nestmann, franz