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Significance of scintigraphy for the localisation of obscure gastrointestinal bleedings

World Journal of Gastroenterology 2008年第32期14卷 5015-5019页

作者： tanja brünnler Frank Klebl Sascha Mundorff Christoph Eilles Michael Reng Hans von Korn Jürgen Schlmerich Julia Langgartner Stefan Grüne Department of Internal Medicine I University of Regensburg Department of Surgery Hospital Neumarkt Department of Nuclear Medicine University of Regensburg Department of Internal Medicine Hospital Bogen Department of Internal Medicine II Hospital Hetzelstift

AIM： To determine the role of scintigraphy in patients with gastrointestinal （GI） bleeding of unknown Iocalisation. METHODS： We performed retrospective analyses on 92 patients receiving scintigraphies from 1993 to 2000 in the University of Regensburg hospital, which were done for Iocalisation of GI bleeding as a diagnostic step after an unsuccessful endoscopy. In addition to the scintigraphies, further diagnostic steps such as endoscopy, angiography or operations were performed. In some of the scintigraphies with negative results, a provocation test for bleeding with heparinisation was carried out. RESULTS： 73% of all scintigraphies showed a positive result. In 4.5% of the positive results, the source was located in the stomach, in 37% the source was the small bowel, in 25% the source was the right colon, in 4.5% the source was the left colon, and in 20% no clear Iocalisation was possible. Only 4% of all scintigraphies were false positive. A reliable positive scintigraphy was independent of the age of the examined patient. A provocation test for bleeding with heparin resulted in an additional 46% of positive scintigraphies with a reliable Iocalisation in primary negative scintigraphies. CONCLUSION- Our results show that scintigraphy and scintigraphy with heparin provocation tests are reliable procedures. They enable a reliable Iocalisation in about half of the obscure GI-bleeding cases. Scintigraphy is superior to angiography in locating a bleeding. It is shown that even in the age of video capsule endoscopy and double-balloon enteroscopy, scintigraphy provides a reliable and directed localization of GI bleeding and offers carefully targeted guidance for other procedures.

关键词： Gastrointestinal bleeding Scintigraphy Localisation Angiography

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Activation of commercial Pt/C catalyst toward glucose electro-oxidation by irreversible Bi adsorption

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Journal of Energy Chemistry 2018年第5期27卷 1446-1452页

作者： Petri Kanninen tanja Kallio Department of Chemistry and Material Science Aalto University P.O. Box 16100 00076 Aalto. Finland Applied Electrochemistry KTH-Royal Institute of Technology Teknikringen 42 10044 Stockholm Sweden

The effect of irreversibly adsorbed Bi on commercial Pt/C catalyst toward glucose electro-oxidation re- action （GOR） in different electrolytes （acidic, neutral, alkaline） is studied. Bi is successfully deposited on Pt/C from Bi3＋ containing acidic solution from 0 to 90% coverage degree. The stability of the Bi layer in acid and alkaline corresponded to previous studies and started to dissolve at 0.7 V and 0.8 V versus re- versible hydrogen electrode （RIIE）, respectively. However, in neutral phosphate buffer the layer showed remarkable stability to at least 1.2V versus RHE. Bi modification at low （20%） and high （80%） coverage showed the highest increase in the activity of Pt/C toward GOR by a factor up to 7 due to the increased poisoning resistance of the modified catalyst. The effect of poisoning was especially reduced at high Bi coverage （80%）, which shows that adsorbate blocked by Bi through the third-body effect is effective. Finally, with or without Bi modification GOR on PtIC was most active in alkaline conditions.

关键词： Glucose electro-oxidation Platinum Bismuth Catalyst poisoning Renewable resources

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Tendril-Based Climbing Plants to Model, Simulate and Create Bio-Inspired Robotic Systems

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Journal of Bionic Engineering 2015年第2期12卷 250-262页

作者： Renato Vidoni tanja Mimmo Camilla Pandolfi Faculty of Science and Technology Free University of Bolzano Piazza universith 3 91 O0 Bolzano Italy European Space Agency-Advanced Concepts Team Estec Noordwjik Netherlands

Bioinspiration can be considered one of the keys for future smart and versatile robotic systems. Plants could be an im- portant source of ideas despite the fact that they have not yet been deeply observed and considered. In this paper, climbing tendril-bearer plants that, by means of irritable filiform organs called tendrils, search for a support, grasp it and climb to gain height, have been used to study and develop an effective climbing robot. The study aimed first to evaluate the main movements and behaviors of the tendril from a biomimetic point of view. The tendril complexity was then simplified, a robotic model was developed and a kinematic simulator was designed and implemented to visualize and evaluate the chosen system. Finally, based on the biological, technical and numerical evaluations, the main tendril behaviors were replicated by proof of concept devices made of smart materials to move towards a practical realization and to replicate the simulated results. The designed proof of concept prototypes showed food repeatability and feasibility.

关键词： climbing plants robotic tendril kinematic model Shape-Memory-Alloy (SMA) grasping

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Synthesis of iron（ll） complexes with asymmetric N2O2 coordinating Schiff base-like ligands and their spin crossover properties

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Frontiers of Chemical Science and Engineering 2018年第3期12卷 400-408页

作者： Wolfgang Bauer tanja Ossiander Birgit Weber Department of Chemistry University of Bayreuth 95440 Bayreuth Germany

The synthesis of new Schiff base-like ligands with asymmetric substituents pattern and their iron complexes with pyridine as axial ligand is described. Two of the ligands and one of the iron（II） complexes were characterized by single crystal X-ray structure analysis. One of the the iron（II） complexes shows spin crossover behavior while the others remain in the high spin state. The influence of the reduced symmetry of the ligand on the properties of the complexes is discussed.

关键词： iron Schiffbase-like ligands magnetism spin crossover X-ray structures

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Artemisinin and artemisinin derivatives as anti-fibrotic therapeutics

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Acta Pharmaceutica Sinica B 2021年第2期11卷 322-339页

作者： David Dolivo Pamela Weathers tanja Dominko Department of Surgery Northwestern University-Feinberg School of MedicineChicagoIL 60611USA Department of Biology and Biotechnology Worcester Polytechnic InstituteWorcesterMA 01609USA

Fibrosis is a pathological reparative process that can occur in most organs and is responsible for nearly half of deaths in the developed *** considerable research,few therapies have proven effective and been approved clinically for treatment of *** compounds are best known as antimalarial therapeutics,but they also demonstrate antiparasitic,antibacterial,anticancer,and antifibrotic *** we summarize literature describing anti-fibrotic effects of artemisinin compounds in in vivo and in vitro models of tissue fibrosis,and we describe the likely mechanisms by which artemisinin compounds appear to inhibit cellular and tissue processes that lead to *** consider alternative routes of administration of artemisinin for treatment of internal organ fibrosis,we also discuss the potential for more direct oral delivery of Artemisia plant material to enhance bioavailability and efficacy of artemisinin compared to administration of purified artemisinin drugs at comparable *** is our hope that greater understanding of the broad anti-fibrotic effects of artemisinin drugs will enable and promote their use as therapeutics for treatment of fibrotic diseases.

关键词： Fibrosis Artemisia Artemisinin Artesunate Fibroblast Myofibroblast Scar TGF-β

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Types of lime binders in mortars used for the construction of the Ming Great Wall of China and their importance for the development of a conservation strategy

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Built Heritage 2022年第1期6卷 55-75页

作者： tanja Dettmering Shibing Dai Architectural Conservation Laboratory CAUP Tongji University No.1239 Siping RoadShanghai 200092China

The most obvious characteristics of the Ming Great Wall are external masonry walls made of natural stones,bricks and lime *** to the chemical and mineralogical compositions of the original bedding and pointing mortars,dolomitic lime binder was used dominantly in the construction of the Ming Great Wall in provinces such as those around Beijing and ***-rich lime and air lime with low natural hydraulically reactive phases,which are hydrated and react slowly with the carbon dioxide in air to form calcium carbonate,were used in some western *** and microscopic investigations show that both dolomitic and calcium-rich lime mortars are almost *** dolomitic lime mortars are characterised by high strengths,low porosities and dense micro-scale *** most recent conservation principle is to preserve the Ming Great Wall as a ***,the conservation strategy should be redefined in terms of *** some of the damage to the Great Wall is related to reactions between dolomitic lime mortars and air pollutants,calcium-rich lime binders should be used for conservation and even for restoration of those parts of the Great Wall that were originally built with dolomitic *** based on natural hydraulic lime and calcium-rich lime gauged with natural pozzolana might be more compatible than other binders"for the structural consolidation of the ruins of the GreatWall.

关键词： Great Wall Masonry ruins Lime mortars Dolomitic lime Deterioration Conservation

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Modernised Traditional Lime Plasters for Modern Historic Living of Built Heritage:Case Studies from Germany and Reflection for China

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Built Heritage 2019年第1期3卷 26-36页

作者： tanja Dettmering August-Bebel-Schule Berufliche Schule des Kreises Offenbach am MainGermany

Traditional plasters were generally produced until about the middle of the 20^(th) *** traditional plasters,lime plaster in Europe occupies a position of outstanding *** play a key role as a protective and decorative outer layer in the care and rehabilitation of the built *** meet the needs for protecting masonry and living in historic buildings in the modern age,traditional lime plasters can be modified to fulfill technical and aesthetic *** paper makes an assessment of the use of traditional and modern lime plasters in *** rediscovery of lime plaster as a material for use in cultural heritage conservation has led to the application of traditional and modern plasters along with advanced guidelines and standards for their production and *** China,a kind of lime-system has recently been developed that is historically and technically compatible with the types used historically;the new types lend itself well to use in modern conservation.

关键词： traditional plaster lime built heritage modern living in historic structures

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The future of underground spatial planning and the resulting potential risks from the point of view of mining subsidence engineering

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International Journal of Mining Science and Technology 2020年第1期30卷 93-98页

作者： Carolina brücker Axel Preuβe Institute for Mine Surveying Mining Subsidence Engineering and Geophysics in MiningRWTH Aachen UniversityWüllnerstr.2Aachen 52062Germany

The topic of ground movements in Germany has been studied extensively in the past,especially in the field of active *** active hard coal mines in Germany were finally shut down in 2018 and lignite mining is expected to take place only until *** so-called long-term liabilities of the mine operators in Germany include,among other things,the long-term guarantee of stability and thus the monitoring of ground *** far,the economic use of underground mining in Germany was mainly the supply of raw *** the future,the underground storage of compressed air,methane or hydrogen will play an important role in renewable energy supply and climate ***,the underground storage space will become more important and the spatial planning is essential to ensure availability of safe underground openings for the various options of environmentally friendly energy ***,this renewed usage of underground openings may also bring new and sometimes unknown challenges of geomechanical *** aftermath of hard coal and lignite mining will be an increasing challenge in mining subsidence *** the other hand,new possibilities due to underground spatial planning may lead to subsidence and/or heaving of the upper surface.

关键词： Mining Surveying Underground spatial planning Mining engineering Renewable energies

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Developing molecular-level models for organic field-effect transistors

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National Science Review 2021年第4期8卷 167-180页

作者： Haoyuan Li Jean-Luc brédas School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics Georgia Institute of Technology Department of Chemistry and Biochemistry University of Arizona

Organic field-effect transistors(OFETs) are not only functional devices but also represent an important tool for measuring the charge-transport properties of organic semiconductors(OSs). Thus, efforts to understand the performance and characteristics of OFET devices are not only useful in helping achieve higher device efficiencies but also critical to ensuring accuracy in the evaluations of OS charge *** studies rely on OFET device models, which connect the measured current characteristics to the properties of the OSs. Developing such OFET models requires good knowledge of the charge-transport processes in OSs. In device active layers, the OS thin films are either amorphous(e.g. in organic light-emitting diodes and organic solar cells) or crystalline(e.g. those optimized for charge transport in OFETs). When the electronic couplings between adjacent OS molecules or polymer chain segments are weak, the charge-transport mechanism is dominated by hopping processes, which is the context in which we frame the discussion in this Review. Factors such as disorder, mobility anisotropy, traps, grain boundaries or film morphology all impact charge transport. To take these features fully into account in an OFET device model requires considering a nano-scale, molecular-level resolution. Here, we discuss the recent development of such molecular-resolution OFET models based on a kinetic Monte Carlo approach relevant to the hopping regime. We also briefly describe the applicability of these models to high-mobility OFETs,where we underline the need to extend them to incorporate aspects related to charge delocalization.

关键词： organic semiconductors charge transport kinetic Monte Carlo simulations mobility measurements gradual channel approximation

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Prediction of the biogas production using GA and ACO input features selection method for ANN model

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Information Processing in Agriculture 2019年第3期6卷 349-356页

作者： tanja Beltramo Michael Klocke Bernd Hitzmann Institute of Food Science and Biotechnology University of HohenheimStuttgart 70599Germany Leibniz Institute for Agricultural Engineering and Bioeconomy Potsdam 14469Germany

This paper presents a fast and reliable approach to analyze the biogas production process with respect to the biogas production *** experimental data used for the developed models included 15 process variables measured at an agricultural biogas plant in *** this context,the concentration of volatile fatty acids,total solids,volatile solids acid detergent fibre,acid detergent lignin,neutral detergent fibre,ammonium nitrogen,hydraulic retention time,and organic loading rate were *** neural networks(ANN)were established to predict the biogas production *** ant colony optimization and genetic algorithms were implemented to perform the variable *** identified the significant process variables,reduced the model dimension and improved the prediction capacity of the ANN *** best prediction of the biogas production rate was obtained with an error of prediction of 6.24%and a coefficient of determination of R2=0.9.

关键词： Ant colony optimization Artificial neural networks Biogas Genetic algorithm

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