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The psyche and the gut

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World Journal of Gastroenterology 2007年第25期13卷 3405-3408页

作者： Paul Enck ute Martens Sibylle Klosterhalfen University Hospitals Tübingen Department of Internal Medicine Ⅵ Psychosomatic Medicine and Psychotherapy Germany

Research on gut-brain interactions has increased over the last decade and has brought about a number of new topics beyond ＂classical＂ subjects, such as ＂stress＂ and personality; which have dominated the psychosomatic literature on gastrointestinal disorders over the past century. These novel topics include brain imaging of intestinal functions, placebo responses in gastroenterology, learning of gastrointestinal symptoms, quality of life in patients with intestinal complaints, and psychotherapy and familial aggregation of functional intestinal disorders. Currently, these new topics appear with a frequency of 1% to 3% in leading gastroenterological journals, either as data presentation or review papers. Increasing focus underlines the importance of enhandng our understanding on how the psyche and the brain communicate in order to better meet the needs of our patients.

关键词： Gut-brain interactions Psyche Functionalbowel disorders Irritable bowel syndrome

A Population Balance Model for Disperse Systems:Particle Size Distribution in Suspension Polymerization

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Chinese Journal of Chemical Engineering 1999年第4期7卷 332-344页

作者：陈中 Werner Pauer H.-U.Moritz Jan Prss Hans-Joachim warnecke Chemical Engineering University of PaderbornPaderborn 33098Germany

On the basis of population balance a mathematical model is developed to describe the formation of polymer particle in styrene suspension polymerization. The characteristics of coalescence and breakage of droplets and the gel effect are analyzed in particular. Parameters of the models are estimated by experimental data on reaction conversion and particle size distribution. The results show that the model is suitable for predicting polymerization processes.

关键词： population balance model styrene suspension polymerization particle size distribution

Explaining the influence of dopant concentration and excitation power density on the luminescence and brightness of β-NaYF4:Yb^3+,Er^3+ nanoparticles:Measurements and simulations

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Nano Research 2019年第8期12卷 1871-1879页

作者： Martin Kaiser Christian Wurth Marco Kraft Tero Soukka ute Resch-Genger Division Biophotonics Federal Institute for Materials Research and Testing (BAM)Richard-Willstaetter-Str. 11D-12489 BerlinGermany Department of Biotechnology University of TurkuKiinamyllynkatu 10TurkuFI-20520Finland

We assessed the influence of Yb^3+ and Er34 dopant concentration on the relative spectral distribution, quantum yield (Фuc), and decay kinetics of the upconversion luminescence (UCL) and particle brightness (BUC) for similarly sized (33 nm) oleate-capped p-NaYF4:Yb3t,Er^3+ upconversion (UC) nanoparticles (UCNPs) in toluene at broadly varied excitation power densities (F). This included an Yb^3+ series where the Yb^3+ concentration was varied between 11%—21% for a constant Er^3+ concentration of 3%, and an Er^3+ series, where the Er^3+ concentration was varied between 1%-4% for a constant Yb^3+ concentration of 14%. The results were fitted with a coupled rate equation model utilizing the UCL data and decay kinetics of the green and red Er34 emission and the Yb34 luminescence at 980 nm. An increasing Yb34 concentration favors a pronounced triphotonic population of 4F9/2 at high P by an enhanced back energy transfer (BET) from the 4G11/2 level. Simultaneously, the Yb^3+-controlled UCNPs absorption cross section overcompensates for the reduction in Фuc with increasing Yb^3+ concentration at high P, resulting in an increase in Sue. Additionally, our results show that an increase in Yb34 and a decrease in Er^3+ concentration enhance the color tuning range by P. These findings will pave the road to a deeper understanding of the energy transfer processes and their contribution to efficient UCL, as well as still debated trends in green-to-red intensity ratios of UCNPs at different P.

关键词： upconversion quantum yield color tuning nanoparticles dopant concentration rate equation model

In vitro Response of Human Mesenchymal Stromal Cells to Titanium Coated Peek Films and Their Suitability for Magnetic Resonance Imaging

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Journal of Materials Science & Technology 2015年第5期31卷 427-436页

作者： Cindy Elschner Carolin Noack Carolin PreilBler Andreas Krause Ulrich Scheler ute Hempel Leibniz-Institut fr Polymerforschung Dresden e.V. Hohe Str.601069 DresdenGermany CRTD/DFG-Center for Regenerative Therapies Dresden Fetscherstr.10501307 DresdenGermany Institut fr Physiologische Chemie Technische Universitt DresdenFiedlerstr.4201307 DresdenGermany NaMlab gGmbH Nthnitzer Str.6401187 DresdenGermany

Medical imaging is an important tool for the post-operative checkup of an accurate position of an implant as well as for monitoring the integration in the adjacent tissue that may influence the success of a medical ***,the possibility to use imaging methods is associated with the implant material and all the established metallic materials for surgery do not show a proper 'imaging compatibility'.The present study is a combined investigation of the in vitro response to human mesenchymal stromal cells（hMSC） and magnetic resonance imaging（MRI） compatibility of the potential material combination polyetheretherketone/titanium（PEEK/Ti） for medical *** of the advantageous imaging properties and the mechanical and chemical stability,PEEK becomes more and more an alternative to common metallic implant materials like titanium or ***,PEEK is a bioinert material having a limited ability for direct bone *** to its excellent biocompatibility,Ti was chosen as coating material to enhance the cellular *** result is a combination with advantageous properties:the magnetic susceptibility and elastic modulus close to bone,corrosion resistance and mechanical flexibility of PEEK and the excellent biocompatibility of *** appearance of metal-related artifact was discussed in electrical resistivity and magnetic ***,two titanium coatings have been investigated:a complete coating and a structured surface avoiding surface *** determine the in vitro biocompatibility,the cell responses were assessed in terms of the overall morphology of the hMSC and their cell area distribution,proliferation,osteogenic differentiation and mineral *** cellular stress was evaluated by the prostaglandin *** bonded materials both produced no disturbing artifacts in magnetic resonance *** to the pure PEEK material,the titanium coated specimens showed an enhanced biocompatibilit

关键词： Polyetheretherketone Titanium coating Biocompatibi

Polarity,intramolecular charge transfer,and hydrogen bond comediated solvent effects on the optical properties of graphene quantum dots

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Nano Research 2023年第1期16卷 45-52页

作者： Yalei Hu Christof Neumann Lena Scholtz Andrey Turchanin ute Resch-Genger Siegfried Eigler Institute of Chemistry and Biochemistry Freie Universität BerlinTakustraße 314195 BerlinGermany Institute of Physical Chemistry and Abbe Center of Photonics Friedrich Schiller University JenaLessingstraße 1007743 JenaGermany Federal Institute for Materials Research and Testing(BAM) Division BiophotonicsRichard Willstätter Straße 1112489 BerlinGermany

Graphene quantum dots(GQDs)have attracted increasing attention due to their favorable optical properties and have been widely used,e.g.,in the biomedical ***,the properties related to the chemical structure of GQDs,resulting in solventdependent optical properties,still remain ***,we present the synthesis of long-wavelength emitting GQDs with a size of about 3.6 nm via a solvothermal method using oxo-functionalized graphene(oxo-G)and p-phenylenediamine as precursors and their structural and surface chemical analysis by transmission electron and atomic force microscopy(TEM;AFM)as well as Fourier-transform infrared,Raman,and X-ray photoelectron spectroscopy(FTIR;Raman;XPS).Subsequently,the influence of solvent polarity and proticity on the optical properties of the as-prepared GQDs bearing–OH,–NH_(2),–COOH and pyridine surface groups was *** on the results of the absorption and fluorescence(FL)studies,a possible luminescence mechanism is *** observed solvent-induced changes in the spectral position of the FL maximum,FL quantum yield,and FL decay kinetics in protic and aprotic solvents of low and high polarity are ascribed to a combination of polarity effects,intramolecular charge transfer(ICT)processes,and hydrogen ***,the potential of GQDs for the optical sensing of trace amount of water was *** results of our systematic spectroscopic study will promote the rational design of GQDs and shed more light on the FL mechanism of carbon-based fluorescent nanomaterials.

关键词： graphene quantum dots(GQDs) polarity intramolecular charge transfer(ICT) hydrogen bond optical properties

Arabidopsis OBG-Like GTPase （AtOBGL）Is Localized in Chloroplasts and Has an Essential Function in Embryo Development

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Molecular Plant 2009年第6期2卷 1373-1383页

作者： Fatima Chigri Claudia Sippel Manuela Kolb ute C. Vothknecht Center for Integrated Protein Science (Munich) Department of Biology LMU Munich D-81377 Munich Germany Department of Biology I Botany LMU Munich D-82152 Planegg-Martinsried Germany

OBG-like GTPases, a subfamily of P-loop GTPases, have divers and important functions in bacteria, including initiation of sporulation, DNA replication, and protein translation. Homologs of the Bacillus subtilis spo0B GTP-binding protein （OBG） can be found in plants and algae but their specific function in these organisms has not yet been elucidated. Here, it is shown that ATSG18570 encodes an Arabidopsis thaliana OBG-like protein （AtOBGL） that is localized in chlor- oplasts. In contrast to the bacterial members of this protein family, AtOBGL and other OBG-like proteins from green algae and plants possess an additional N-terminal domain, indicating functional adaptation. Disruption of the gene locus of ATOBGL by TDNA insertion resulted in an embryo-lethal phenotype and light microscopy using Normarski optics revealed that embryo maturation in the atobgl mutant is arrested at the late globular stage before development of a green embryo. Expression of 35S：：ATOBGL within the atobgl mutant background could rescue the mutant phenotype, confirming that embryo-lethality is caused by the loss of AtOBGL. Together, the data show that the bacterial-derived OBG-like GTPases have retained an essential role in chloroplasts of plants and algae. They furthermore corroborate the significance of chloroplast functions for embryo development -- an important stage within the Arabidopsis lifecycle.

关键词： GTPase OBG embryo development chloroplast.

Particle-size-dependent upconversion luminescence of NaYF4:Yb,Er nanoparticles in organic solvents and water at different excitation power densities

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Nano Research 2018年第12期11卷 6360-6374页

作者： Marco Kraft Christian Würth Verena Muhr Thomas Hirsch ute Resch-Genger Federal Institute for Matefiab Research and Testing (BAM) Division1.2BiophotonicsRichard-Willstaetter-Str.1112489BerlinGermany Institute of Analytical Chemistry Chemo-and BiosensorsUniversity of Regensburg93040RegensburgGermany

A systematic study of the luminescence properties of monodisperse β-NaYF4: 20% Yb3+, 2% Er3+ upconversion nanoparticles (UCNPs) with sizes ranging from 12–43 nm is presented utilizing steady-state and time-resolved fluorometry. Special emphasis was dedicated to the absolute quantification of size- and environment-induced quenching of upconversion luminescence (UCL) by high-energy O–H and C–H vibrations from solvent and ligand molecules at different excitation power densities (P). In this context, the still-debated population pathways of the 4F9/2 energy level of Er3+ were examined. Our results highlight the potential of particle size and P value for color tuning based on the pronounced near-infrared emission of 12 nm UCNPs, which outweighs the red Er3+ emission under “strongly quenched” conditions and accounts for over 50% of total UCL in water. Because current rate equation models do not include such emissions, the suitability of these models for accurately simulating all (de)population pathways of small UCNPs must be critically assessed. Furthermore, we postulate population pathways for the 4F9/2 energy level of Er3+, which correlate with the size-, environment-, and P-dependent quenching states of the higher Er3+ energy levels.

关键词： upconversion nanoparticle quenching diameter water cyclohexane

Differential c-erbB-1 and c-erbB-2 mRNA expression in cancer of the pancreas compared with cancer of the papilla of Vater

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World Journal of Gastroenterology 2006年第3期12卷 437-442页

作者： KlausLPrenzel utewarnecke-eberz JanBrabender StephanEBaldus ElfriedeBollschweiler ChristianAGutschow UtaDrebber ArnulfHHoelscher PaulMSchneider Department of Visceral and Vascular Surgery University of Cologne50931 CologneGermany Institute of PathologyUniversity of Cologne50931 CologneGermany

AIM： We examined quantitative mRNA expression of growth factor receptors （c-erbB-1, c-erbB-2） and the anti-apoptosis gene survivin known to be regulated in pancreatic adenocarcinomas and compared the expression pattern with that in carcinomas of the papilla of Vater. METHODS： Quantitative real-time reverse transcriptase- PCR （QRT-PCR, Taqman^TM） was performed to analyze mRNA expression levels of c-erbB-1, c-erbB-2 and survivin in normal and corresponding tumor samples of 31 pancreatic adenocarcinomas and 8 cancers of the papilla of Vater. RESULTS： The overall median mRNA expression of survivin was significantly increased in both adenocarcinoma of the pancreas （P〈0.01） and papilla of Vater （P〈0.008） compared with uninvolved normal control tissue. In pancreatic cancer, expression of c-erbB-1 was significantly decreased compared with the normal pancreatic tissue （P〈0.03）, whereas in the cancer of the papilla of Vater expression of c-erbB-2 was significantly downregulated （P〈0.05） compared with the paired normal samples. Gene expression was not associated with tumor stage, differentiation or prognosis. CONCLUSION： The common anti-apoptosis gene survivin is overexpressed both in the cancer of the papilla of Vater and pancreas. In contrast, the growth factor receptor genes c-erbB-1 and c-erbB-2 are differentially regulated in both tumor entities adding further evidence that pancreatic cancer is biologically different from the cancer of papilla of Vater.

关键词： Pancreatic cancer Ampullary cancer Growth factor receptor Gene expression RT-PCR Survivin

Seed selections for crystallization of calcium phosphate for phosphorus recovery

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Journal of Environmental Sciences 2007年第5期19卷 591-595页

作者： SONG Yong-hui Dietfried DONNERT ute BERG Peter G. WEIDLER Rolf NUEESCH Chinese Research Academy of Environmental Sciences Beijing 100012 China Institute for Technical Chemistry-Section of Water- and Geo-technology （ITC-WGT） Research Centre of Karlsruhe Karlsruhe D-76021 Germany

Seed induces and promotes the crystallization of calcium phosphate, and acts as carrier of the recovered phosphorus （P）. In order to select suitable seed for P recovery from wastewater, three seeds including Apatite （AP）, Juraperle （JP） and phosphate-modified Juraperle （M-JP） were tested and compared. Batch and fixed-bed column experiments of seeded crystallization of calcium phosphate were undertaken by using synthetic wastewater with 10 mg/L P phosphate. It shows that AP has bad enduring property in the crystallization process, while JP has better performance for multiple uses, and M-JP is a hopeful seed for P recovery by crystallization of calcium phosphate.

关键词： crystallization seed phosphorus recovery Juraperle Apatite