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Changes of smooth muscle contractile filaments in small bowel atresia

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World Journal of Gastroenterology 2012年第24期18卷 3099-3104页

作者： stefan Gfroerer Henning Fiegel Priya Ramachandran Udo Rolle Roman Metzger Department of Paediatric Surgery Goethe-University Frankfurt60590 FrankfurtGermany Kanchi Kamakoti Childs Trust Hospital Chennai 600034India Department of Paediatric Surgery University of Leipzig04317 LeipzigGermany

AIM:To investigate morphological changes of intestinal smooth muscle contractile fibres in small bowel atresia ***:Resected small bowel specimens from small bowel atresia patients(n = 12) were divided into three sections(proximal,atretic and distal).Standard histology hematoxylin-eosin staining and enzyme immunohistochemistry was performed to visualize smooth muscle contractile markers-smooth muscle actin(SMA) and desmin using conventional paraffin sections of the proximal and distal *** bowel from agematched patients(n = 2) undergoing Meckel's diverticulum resection served as ***:The smooth muscle coat in the proximal bowel of small bowel atresia patients was thickened compared with control tissue,but the distal bowel was *** of smooth muscle contractile fibres SMA and desmin within the proximal bowel was slightly reduced compared with the distal bowel and control *** were no major differences in the architecture of the smooth muscle within the proximal bowel and the distal *** proximal and distal bowel in small bowel atresia patients revealed only minimal differences regarding smooth muscle morphology and the presence of smooth muscle contractile filament ***:Changes in smooth muscle contractile filaments do not appear to play a major role in postoperative motility disorders in small bowel atresia.

关键词： Small bowel atresia Enteric nervous sys-tem Smooth muscle Motility disorder

Luminescence study of europium(III) tris(β-diketonato)/phosphonate complexes in chloroform

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Journal of Rare Earths 2008年第2期26卷 185-191页

作者： stefan Lis Zbigniew Piskula Krzysztof Staninski Sayaka Tamaki Masayuki Inoue Yuko Hasegawa Department of Rare Earths Faculty of Chemistry Adam Mickiewicz University Grunwaldzka 6 Department of Chemistry Faculty of Science Science University of Tokyo

The extraction of Eu（Ⅲ） with β-diketone, HA, and monodentate or bidentate Lewis bases, B, into chloroform and the luminescence properties of the extracted species were studied. Pivaloyltrifluoroacetone, Hpta, and 2-thenoyltfifluoroacetone, Htta, were used as the β-diketones. The Lewis bases, B, were tetraethyl methylene diphosphonate, POPO, which was bidentate, and diethyl benzylphosphonate, PhPO which was monodentate. Based on the extraction data, the stability constants, log β, of the first complexes between tfis（β-diketonato）Eu（Ⅲ） and the phosphonate, EuA3B, were determined to be 6.0 for the POPO complex and 3.40 for the PhPO complex. The Eu（Ⅲ） luminescence intensity in the EuA3POPO was larger than EuA3 where A was either pta or tta at similar concentrations of Eu（Ⅲ）, while that in Eu（pta）3PhPO was stronger than EuA3; however, in Eu（tta）3PhPO, it was weaker than Eu（tta）3. The POPO functions as a sensitizer, and the PhPO functions as a quencher for the tta chelate and as a sensitizer for the pta chelate. From the lifetime and quantum yield, φ, of the Eu（Ⅲ） luminescence in the complexes as well as the observation of the extractability of Eu（Ⅲ） with the Hpta and the phosphonates and of the luminescence spectra of the complexes, it was confirmed that the extraction of Eu（Ⅲ） was remarkably enhanced with a β-diketonate and a strong Lewis base, and also the ternary complex that was formed as the extracted species, showed luminescence enhancement. This phenomenon may be due the formation of a strong bond between the Eu（Ⅲ） and the strong Lewis base leading to more hydrophobicity in the extracted species and also to more effective energy transfer from the Lewis base to the Eu（Ⅲ）. It was not significant whether the donor atoms were n or O.

关键词： tris(β-diketonato)Eu(Ⅲ) extraction luminescence phosphonate ligands rare earths

Channel-resolved subcycle interferences of electron wave packets emitted from H_(2) in two-color laser fields

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High Power Laser Science and Engineering 2016年第4期4卷 1-7页

作者： Xinhua Xie stefan Roither Daniil Kartashov Li Zhang Andrius Baltuska Markus Kitzler Photonics Institute Technische Universitat Wien Institute of Theoretical Chemistry University of Vienna

We report on the observation of subcycle interferences of electron wave packets released during strong field ionization of H_2 with cycle-shaped two-color laser fields. With a reaction microscope we measure three-dimensional momentum distributions of photoelectrons correlated with either H_2^+ or protons within different energy ranges generated by dissociation of H_2^+. We refer to these different types of photoelectrons as channels. Our results show that the subcycle interference structures of electron wave packets are very sensitive to the cycle shape of the two-color laser field. We explain this behavior by the dependence of the ionization time within an optical cycle on the shape of the laser field cycle. The subcycle interference structures can be further used to obtain insight into the subcycle dynamics of molecules during strong field interaction.

关键词： molecular dynamics strong field ionization wave packet interference

Assessing stress conditions and impact velocities in fluidized bed opposed jet mills

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Particuology 2020年第6期18卷 12-22页

作者： Alexander Strobel Benedikt Koninger stefan Romeis Florian Schott Karl-Ernst Wirth Wolfgang Peukert Institute of Particle Technology(LFG) Friedrich-Alexander-Universitat Erlangen-NiirnbergCauerstrae 491058 ErlangenGermany

Fluidized bed opposed jet mills are capable of meeting the continuously growing dema nd for contamination-free fine *** this type of jet mill,the solid material is entrained and accelerated by expanding gas jets that are focused onto a focal point in side a fluidized *** resulting particle collisions induce *** process is affected by the relative particle velocities and the number of particle-particle ***,both quantities are ***,to date,neither relative particle velocities nor collision frequencies in such units have been *** present work introduces an innovative method to assess the stressing conditions in jet mills *** this end,mixtures of glass and ductile metal microspheres were used,with the latter employed in small ***-particle collisions between the aluminum and glass spheres lead to the formation of dents on the *** size and number of these dents are associated with the individual collision velocities and overall collision *** correlation between dent size and collision velocity was obtained from finite element calculations based on empirical *** proposed approach was validated using particle image velocimetry during secondary gas injection into a fluidized bed *** this case the effect of the distance between two opposed nozzles was *** a lab-scaled fluidized bed opposed jet mill the effects of gas pressure and hold-up were *** particle velocities were found to be sign ificantly lower tha n the gas velocities,while the nu mber of contacts per particle was determined to be extremely high.

关键词： Fluidized bed opposed jet mill Single particle probes Finite element modeling Stress number distribution Relative velocity distribution

Landslide susceptibility: a statistically-based assessment on a depositional pyroclastic ramp

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Journal of Mountain Science 2019年第3期16卷 561-580页

作者： Franny G.MURILLO-GARCíA stefan STEGER Irasema ALCánTARA-AYALA Institute of Geography National Autonomous University of Mexico (UNAM) Institute for Earth Observation Eurac Research

This study aimed to produce a high-quality landslide susceptibility map for Teziutlán municipality, a landslide-prone region in Mexico, which is characterised by a depositional pyroclastic ramp. The heterogeneous quality of available topographic information(i.e. higher resolution digital elevation model only for a sub-region) encouraged to confront modelling results based on two different study area delineations and two raster resolutions. Input data was based on the larger modelling region L15(163 km2) and smaller S(70 km2; located inside L15) with an associated raster cell size of 15 m(region L15 and S15) and 5 m(region S5). The resulting three data sets(L15, S15 and S5) were included into three differently flexible modelling techniques(Generalized Linear Model-GLM, General Additive Model-GAM, Support Vector Machine-SVM) to produce nine landslide susceptibility models. Preceding variable selection was performed heuristically and supported by an exploratory data analysis. The final models were based on the explanatory variables slope angle, slope aspect, lithology, relative slope position, elevation, convergence index, distance to streams, distance to springs and topographic wetness index. The ability of the models to classify independent test data was elaborated using a k-fold cross validation procedure and the AUROC(Area Under the Receiver Operating Characteristic) metric. In general, all produced landslide susceptibility maps depicted the hillslopes of the ravines, which cut the pyroclastic ramp, as prone to landsliding. The modelling results showed that predictive performances(i.e. AUROC values) slightly increased with an increasing flexibility of the applied modelling technique. Thus, SVM performed best, while the GAM outperformed the GLM. This tendency was most distinctive when modelling with the largest landslide sample size(i.e. data set L15; n = 662 landslides). non-linear classifiers(GAMs, SVMs) performed slightly better when trained on the basis of lower

关键词： Landslide susceptibility Pyroclastic ramp Logistic regression Generalized Additive Model Support Vector Machine Cross validation

Preparing for a “dirty bomb” attack: The optimum mix of medical countermeasure resources

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Military Medical Research 2021年第3期8卷 336-351页

作者： Alexis Rump Patrick Ostheim stefan Eder Cornelius Hermann Michael Abend Matthias Port Bundeswehr Institute of Radiobiology Neuherberg Str.n80937 MunichGermany

Background: In radiological emergencies with radionuclide incorporation, decorporation treatment is particularly effective if started early. Treating all people potentially contaminated("urgent treatment") may require large antidote stockpiles. An efficacious way to reduce antidote requirements is by using radioactivity screening equipment. We analyzed the suitability of such equipment for triage purposes and determined the most efficient mix of screening units and antidote daily ***: The committed effective doses corresponding to activities within the detection limits of monitoring portals and mobile whole-body counters were used to assess their usefulness as triage tools. To determine the optimal resource mix, we departed from a large-scale scenario(60,000 victims) and based on purchase prices of antidotes and screening equipment in Germany, we calculated efficiencies of different combinations of medical countermeasure resources by data envelopment analysis. Cost-effectiveness was expressed as the costs per life year saved and compared to risk reduction opportunities in other sectors of society as well as the values of a statistical ***: Monitoring portals are adequate instruments for a sensitive triage after cesium-137 exposure with a high screening throughput. For the detection of americium-241 whole-body counters with a lower daily screening capacity per unit are needed. Assuming that 1% of the potentially contaminated patients actually need decorporation treatment, an efficient resource mix includes 6 monitoring portals and 25 mobile whole-body counters. The optimum mix depends on price discounts and in particular the fraction of victims actually needing treatment. The costeffectiveness of preparedness for a "dirty bomb" attack is less than for common health care, but costs for a life year saved are less than for many risk-reduction interventions in the environmental ***: To achieve economic efficiency a high daily screening ca

关键词： Radiological emergency Dirty bomb Medical countermeasures Radionuclide incorporation Decorporation treatment Screening Efficiency Data envelopment analysis

A theoretical model for pattern discovery in visual analytics

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Visual Informatics 2021年第1期5卷 23-42页

作者： natalia Andrienko Gennady Andrienko Silvia Miksch Heidrun Schumann stefan Wrobel Fraunhofer Institute IAIS Sankt-AugustinGermany City University of LondonLondonUK TU Wien ViennaAustria University of Rostock RostockGermany University of Bonn BonnGermany

The word‘pattern’frequently appears in the visualisation and visual analytics literature,but what do we mean when we talk about patterns?We propose a practicable definition of the concept of a pattern in a data distribution as a combination of multiple interrelated elements of two or more data components that can be represented and treated as a unified *** theoretical model describes how patterns are made by relationships existing between data *** the types of these relationships,it is possible to predict what kinds of patterns may *** demonstrate how our model underpins and refines the established fundamental principles of *** model also suggests a range of interactive analytical operations that can support visual analytics workflows where patterns,once discovered,are explicitly involved in further data analysis.

关键词： Visual analytics Data distribution Pattern Abstraction Data organisation Data arrangement Data variation Pattern discovery

The Chemistry and Biological Activities of natural Products from northern African Plant Families:From Taccaceae to Zygophyllaceae

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natural Products and Bioprospecting 2016年第2期6卷 63-96页

作者： Fidele ntie-Kang Leonel E.njume Yvette I.Malange stefan Gunther Wolfgang Sippl Joseph n.Yong Department of Pharmaceutical Chemistry Martin-Luther University of Halle-WittenbergWolfgang-Langenbeck-Str.406120 Halle(Saale)Germany Department of Chemistry Faculty of ScienceUniversity of BueaP.O.Box 63BueaCameroon Department of Chemistry Faculty of ScienceChemical and Bioactivity Information CentreUniversity of BueaP.O.Box 63BueaCameroon Institute of Pharmaceutical Sciences Research Group Pharmaceutical BioinformaticsAlbert-Ludwigs-Universitat FreiburgHermann-Herder-Strasse 979104 FreiburgGermany

Traditional medicinal practices have a profound influence on the daily lives of people living in developing countries,particularly in Africa,since the populations cannot generally afford the cost of Western *** have undertaken to investigate the correlation between the uses of plants in Traditional African medicine and the biological activities of the derived natural products,with the aim to validate the use of traditional medicine in northern African *** literature is covered for the period 1959-2015 and part III of this review series focuses on plant families with names beginning with letters T to *** authors have focused on curating data from journals in natural products and *** each journal home page,a query search based on country name was *** articles‘‘hits’’were then verified,one at a time,that the species was harvested within the northern African geographical *** current data partly constitutes the bases for the development of the northern African natural compounds *** review discusses 284 plant-based natural compounds from 34 species and 11 *** was observed that the ethnobotanical uses of less than 40%of the plant species surveyed correlated with the bioactivities of compounds identified.

关键词： Africanflora Biologicalactivities Ethnobotany naturalproducts Traditionalmedicine

neutralization of the SARS-CoV-2 Delta variant after heterologous and homologous BnT162b2 or ChAdOx1 nCoV-19 vaccination

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Cellular & Molecular Immunology 2021年第10期18卷 2455-2456页

作者： Swantje I.Hammerschmidt Berislav Bosnjak Günter Bernhardt Michaela Friedrichsen Inga Ravens Alexandra Dopfer-Jablonka Markus Hoffmann stefan Pöhlmann Georg M.n.Behrens Reinhold Förster Institute of Immunology Hannover Medical SchoolHannoverGermany Department for Rheumatology and Immunology Hannover Medical SchoolHannoverGermany Infection Biology Unit German Primate Center-Leibniz Institute for Primate ResearchGöttingenGermany Faculty of Biology and Psychology Georg-August-University GöttingenGöttingenGermany German Center for Infection Research(DZIF) Partner Site Hannover-BraunschweigHannoverGermany German Center for Lung Research(DZL) HannoverGermany Cluster of Excellence RESIST(EXC 2155) Hannover Medical SchoolHannoverGermany

Since the beginning of the COVID-19 pandemic,divergent variants of concern(VoCs)of SARS-CoV-2 have evolved and become the most prevalent SARS-CoV-2 variants in distinct locations at different ***,the Delta variant(B.1.617.2)dominates infection events in large parts of the *** campaigns,however,still use SARS-CoV-2 vaccines based on the spike(S)protein of the original Wuhan virus.

关键词： Delta homologous campaign