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Near-Net-Shaped Objects of RE123 Superconductors byInfiltration Processing

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Tsinghua Science and Technology 2003年第3期8卷 292-306页

作者： E.S.Reddy G.J.schmitz ACCESS Materials and Processes D-52056 AachenGermanyACCESS Materials and ProcessesD-52056 AachenGermany

The fabrication of near-net-shaped objects of RE123 superconductors by 'infiltration processing' is discussed. Near-net-shape processing involves the infiltration of preshaped porous green bodies of either 211 or yttria phases by liquids containing barium cuprates and copper oxides followed by a controlled peritectic solidification. The process yields poly- and also single-crystalline superconducting objects with a shrinkage of less than half of one percent of the green bodies. The preservation of the initial structure of the green bodies results in fabrication of RE 123 in a wide variety of dimensions and complex shapes. The demonstrated products include bulk components like cylinders, single domain thick films on a variety of substrates, freestanding fabrics and open porous superconducting foams. This paper presents a comprehensive description of the infiltration processing technique and the resulting microstructures of the superconducting bodies. The advantages of this technique and practical applications of the processed superconducting structures are highlighted.

关键词： infiltration processing near-net shape shaping joining single domain crystal growth thick films foams applications

Genevestigator Transcriptome Meta-Analysis and Biomarker Search Using Rice and Barley Gene Expression Databases

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Molecular Plant 2008年第6期1卷 851-857页

作者： Philip Zimmermann Oliver Laule Josy schmitz Tomas Hruz Stefan Bleuler Wilhelm Gruissema Department of Biology ETH Zurich Universitaetstrasse 2 8092 Zurich Switzerland Institute of Theoretical Computer Science ETH Zurich Universitaetsstrasse 6 8092 Zurich Switzerland

The wide-spread use of microarray technologies to study plant transcriptomes has led to important discoveries and to an accumulation of profiling data covering a wide range of different tissues, developmental stages, perturbations, and genotypes. Querying a large number of microarray experiments can provide insights that cannot be gained by analyzing single experiments. However, such a meta-analysis poses significant challenges with respect to data comparability and normalization, systematic sample annotation, and analysis tools. Genevestigator addresses these issues using a large curated expression database and a set of specifically developed analysis tools that are accessible over the internet. This combination has already proven to be useful in the area of plant research based on a large set of Arabidopsis data （Grennan, 2006）. Here, we present the release of the Genevestigator rice and barley gene expression databases that con- tain quality-controlled and well annotated microarray experiments using ontologies. The databases currently comprise experiments from pathology, plant nutrition, abiotic stress, hormone treatment, genotype, and spatial or temporal analysis, but are expected to cover a broad variety of research areas as more experimental data become available. The transcriptome meta-analysis of the model species rice and barley is expected to deliver results that can be used for functional genomics and biotechnological applications in cereals.

关键词： Meta-Analysis wide-spread

Lithocholic acid induction of the FGF19 promoter in intestinal cells is mediated by PXR

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World Journal of Gastroenterology 2007年第31期13卷 4230-4235页

作者： Wolfgang Wistuba Carsten Gnewuch Gerhard Liebisch Gerd schmitz Thomas Langmann Institute of Clinical Chemistry and Laboratory Medicine University of Regensburg Regensburg 93053 Germany

To study the effect of the toxic secondary bile acid lithocholic acid （LCA） on the expression of fibroblast growth factor 19 （FGF19） in intestinal cells and to characterize the pregnane-X-receptor （PXR） response of the FGF19 promoter region. METHODS： The intestinal cell line LS174T was stimulated with various concentrations of chenodeoxy- cholic acid and lithocholic acid for several time points. FGF19 mRNA levels were determined with quantitative realtime RT-PCR. FGF19 deletion promoter constructs were generated and the LCA response was analzyed in reporter assays. Co-transfections with PXR and RXR were carried out to study FGF19 regulation by these factors, RESULTS： LCA and CDCA strongly up-regulate FGF19 mRNA expression in LS174T cells in a time and dose dependent manner. Using reporter gene assays with several deletion constructs we found that the LCA responsive element in the human FGF19 promoter maps to the proximal regulatory region containing two poten- tial binding sites for PXR. Overexpression of PXR and its dimerization partner retinoid X receptor （RXR） and stimulation with LCA or the potent PXR ligand rifampicin leads to a significant induction of FGF19 promoter activ- ity in intestinal cells. CONCLUSION： LCA induced feedback inhibition of bile acid synthesis in the liver is likely to be regulated by PXR inducing intestinal FGF19 expression.

关键词： Pregnane X receptor Detoxification Fibroblast growth factor 19 Lithocholic acid

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工作场所噪声职业接触限值制定的研究进展

工业卫生与职业病 2024年第4期50卷 368-373页

作者：曾安可辛佳芮孙新张美辨中国疾病预防控制中心职业卫生与中毒控制所北京100050

目的回顾国内外工作场所噪声职业接触限值研究进展,为进一步修订我国工作场所噪声职业接触限值标准和完善噪声性听力损失的防控提供科学依据。方法本研究检索并比较分析36个国家规定的噪声职业接触限值以及峰度对修订噪声职业接触限值... 详细信息

目的回顾国内外工作场所噪声职业接触限值研究进展,为进一步修订我国工作场所噪声职业接触限值标准和完善噪声性听力损失的防控提供科学依据。方法本研究检索并比较分析36个国家规定的噪声职业接触限值以及峰度对修订噪声职业接触限值标准作用相关中英文文献。结果各国采用噪声能量指标制定了不同噪声类型的噪声职业接触限值,均未考虑噪声时域结构特征。此外,许多欧美国家要求,除了考虑噪声职业接触限值,在应用噪声职业接触限值时还需要考虑噪声与耳毒性物质等有害因素的联合暴露、高危人群易感性、护听器等因素;国内外学者建议,噪声峰度作为听力损失的危险因素之一,应被纳入噪声职业接触限值标准。结论我国工作场所噪声标准亟待完善,应进一步丰富工作场所噪声职业接触限值指标,综合考虑噪声峰度、护听器佩戴、有害因素与噪声的联合暴露、个体易感性等影响因素。

关键词：噪声工作场所职业接触限值职业噪声性听力损失

Measurement of Non-Steady Noise and Assessment of Occupational Hearing Loss Based on the Temporal Structure of Noise

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China CDC weekly 2023年第3期5卷 63-67页

作者： Meibian Zhang anke Zeng Jiarui Xin Xiangjing Gao Wei Qiu Xin Sun National Institute of Occupational Health and Poison Control Chinese Center for Disease Control and PreventionBeijing MunicipalityChina Occupational Health and Radiation Protection Institute Zhejiang Provincial Center for Disease Control and PreventionHangzhou CityZhejiang ProvinceChina Zhejiang Lab Hangzhou CityZhejiang ProvinceChina

Noise-induced hearing loss(NIHL)has become a global public health problem,and the economic burden of hearing loss caused by noise exposure accounts for 19.6%of the economic burden of all risk factors in the workplace(1).The prevalence of occupational NIHL was estimated to be 10%in relevant occupational population in developed countries and 17%–39%(e.g.,textile and petrochemical industries),and 53%–67%(e.g.,cement and automobile industries)in developing countries in Asia,respectively.(2).In China,occupational noiseinduced deafness has become the second primary occupational disease after pneumoconiosis,with the number of reported cases increasing at an average annual rate of 18.68%from 2010 to 2019(3–4).The prevalence of occupational NIHL in the Chinese occupational population was 21.3%,of which 30.2%was related to high-frequency NIHL(an early sign of NIHL)(2).

关键词： occupational prevalence deafness

How Sugars Might Coordinate Chloroplast and Nuclear Gene Expression during Acclimation to High Light Intensities

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Molecular Plant 2014年第7期7卷 1121-1137页

作者： Rainer E. Haiusler Luisa Heinrichs Jessica schmitz Ulf-Ingo Flugge Department of Botany II Cologne Biocenter University of Cologne ZuIpicherstr. 47b 50674 Cologne Germany Present address: Plant Molecular Physiology and Biotechnology Heinrich-Heine-University Universitatsstrasse 1 40225 D~sseldorfGermany

The concept of retrograde control of nuclear gene expression assumes the generation of signals inside the chloroplasts, which are either released from or sensed inside of the organelle. In both cases, downstream signaling path- ways lead eventually to a differential regulation of nuclear gene expression and the production of proteins required in the chloroplast. This concept appears reasonable as the majority of the over 3000 predicted plastidial proteins are encoded by nuclear genes. Hence, the nucleus needs information on the status of the chloroplasts, such as during acclimation responses, which trigger massive changes in the protein composition of the thylakoid membrane and in the stroma. Here, we propose an additional control mechanism of nuclear- and plastome-encoded photosynthesis genes, taking advantage of pathways involved in sugar- or hormonal signaling. Sugars are major end products of photosynthesis and their con- tents respond very sensitively to changes in light intensities. Based on recent findings, we ask the question as to whether the carbohydrate status outside the chloroplast can be directly sensed within the chloroplast stroma. Sugars might syn- chronize the responsiveness of both genomes and thereby help to coordinate the expression of piastome- and nuclear- encoded photosynthesis genes in concert with other, more specific retrograde signals.

关键词： acclimation--physiological assimilate allocation/partitioning carbohydrate metabolism molecular physiology membrane proteins Arabidopsis.

Exogenous sphingomyelinase causes impaired intestinal epithelial barrier function

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World Journal of Gastroenterology 2007年第39期13卷 5217-5225页

作者： Jürgen Bock Gerhard Liebisch Joachim Schweimer Gerd schmitz Gerhard Rogler Department of Internal Medicine I University of RegensburgGermany Institute for Clinical Chemistry University of Regensburg Germany

AIM: To test the hypothesis that hydrolysis of sphingomyelin to ceramide changes the composition of tight junctions (TJs) with increasing permeability of the intestinal epithelium. METHODS: Monolayers of Caco-2 cells were used as an in vitro model for the intestinal barrier. Permeability was determined by quantifi cation of transepithelialflux and transepithelial resistance. Sphingolipid-rich membrane microdomains were isolated by a discontinuous sucrose gradient and characterized by Western-blot. Lipid content of microdomains was analysed by tandem mass spectrometry. Ceramide was subcellularly localized by immunofluorescent ***: Exogenous sphingomyelinase increased transepithelial permeability and decreased transepithelial resistance at concentrations as low as 0.01 U/mL. Lipid analysis showed rapid accumulation of ceramide in the membrane fractions containing occludin and claudin-4, representing TJs. In these fractions we observed a concomitant decrease of sphingomyelin and cholesterol with increasing concentrations of ceramide. Immunofluorescent staining confirmed clustering of ceramide at the sites of cell-cell contacts. Neutralization of surface ceramide prevented the permeability-increase induced by platelet activating factor. CONCLUSION: Our findings indicate that changes in lipid composition of TJs impair epithelial barrier functions. Generation of ceramide by sphingomyelinases might contribute to disturbed barrier function seen in diseases such as inflammatory, infectious, toxic or radiogenic bowel disease.

关键词： Ceramide Cholesterol Tight-junction Caco-2 cells Permeability Inflammatory bowel disease

Separate basolateral and apical phosphatidylcholine secretion routes in intestinally differentiated tumor cells

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World Journal of Gastroenterology 2009年第46期15卷 5821-5826页

作者： Daniel Gotthardt Annika Braun anke Tietje Karl Heinz Weiss Robert Ehehalt Wolfgang R Stremmel Department of Gastroenterology University Hospital Heidelberg

AIM:To investigate whether the secretion of phospha-tidylcholine(PC)in intestinal mucus occurs by apical secretion or via basolateral excretion and to determine its subsequent passage across the tight junctions to the apical ***:We addressed this question using the po-larized intestinally differentiated tumor cell line CaCo-2 grown on filters to confluence in Transwell culture *** released PC and sphingomyelin(Sph)from apical and basolateral media were analyzed by mass ***:The secreted PC species were identical in both compartments indicating the same intracellular origin of ***,PC secretion into the basolateral compart-ment was more effective,and the PC:Sph ratio in the ba-solateral compartment was signif icantly higher than that in the apical compartment(8.18 ± 1.84 vs 4.31 ± 1.22,P = 0.01).Both pathways were temperature sensitive and were unaltered in the presence of ***:The data demonstrate the PC secre-tion capacity of CaCo-2 cells and indicate two sepa-rated apical and basolateral release mechanisms.

关键词： CaCo-2 cells Epithelial cells Mass spectrometry Phosphatidylcholine Secretion Sphingomyelin

Alternative feedstock for the production of activated carbon with ZnCl_(2):Forestry residue biomass and waste wood

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Carbon Resources Conversion 2022年第4期5卷 299-309页

作者： Dominik Bosch Jan OBack David Gurtner Sara Giberti Angela Hofmann anke Bockreis Josef Ressel Centre for Production of Activated Carbon from Municipal Residues Department of EnvironmentalProcess and Energy EngineeringMCI–The Entrepreneurial SchoolUniversitaetsstrasse 156020 InnsbruckAustria Unit of Environmental Engineering Department for InfrastructureUniversity of InnsbruckTechnikerstrasse 136020 InnsbruckAustria Department of Environmental Process and Energy EngineeringMCI–The Entrepreneurial SchoolUniversitaetsstrasse 156020 InnsbruckAustria Institute for Chemical and Energy Engineering BOKU-University of Natural Resources and Life ScienceGregor-Mendel-Strasse 331160 ViennaAustria Department of Civil ChemicalEnvironmentaland Materials EngineeringUniversit`a di BolognaVia Zamboni 3340126 BolognaItaly

In order to substitute fossil resources in activated carbon(AC)production,recent efforts have focused on the utilization of renewable raw *** with important wood industries offer two potentially underestimated resource types:forestry residue biomass(FRB)and waste wood(WW).Although these materials are widely available(approx.130 mio.m3a-1 FRB,approx.50 ***^(-1) WW in the EU),they are mostly valorised through energy production,as they are high in ashes and may be contaminated with organics and heavy *** this study,both FRB and WW were treated via one-step pyrolysis for AC ***_(2) was applied as activating agent at pyrolysis temperatures varying from 400 to 600℃ and residence times between 1 and 3 ***,76 samples were prepared and characterized thoroughly via elemental analysis,N_(2)/CO_(2) ad/-desorption,thermogravimetric analysis(TGA),scanning electron microscopy(SEM),and infrared spectroscopy(FTIR).The produced carbons showed specific surface areas of up to 1430 m2g􀀀1 and a pore size distribution with a micropore share of up to 80%.The presence of oxygen-containing functional groups was confirmed via *** feedstock contamination can be mitigated,as minerals and heavy metals could be leached out(up to-99.15%)by an additional wash step and organic contamination undergoes thermal cracking during *** presented study could be a next step in upcycling considerable waste streams from the wood sector through localised and non-fossil-based AC production.

关键词： Sustainable resources Waste wood Forestry residue Activated carbon Chemical activation Pyrolysis Porosity Functionalized surface