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The clinical impact of bacterial biofilms

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International Journal of Oral Science 2011年第2期3卷 55-65页

作者： Niels Hoiby Oana Ciofu Helle Krogh Johansen Zhi-jun Song Claus Moser Peter Ostrup Jenser soren molin Michael Givskov Tim Tolker-Nieisen Thomas Bjamsholt Department of Clinical Microbiology Rigshospitalet Institute for International Health Medical Microbiology and Immunology BloScience and Technology Biocentrum Danish Technical University

Bacteria survive in nature by forming biofilms on surfaces and probably most, if not all, bacteria （and fungi） are capable of forming biofilms. A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and extracellular DNA. Bacterial biofilms are resistant to antibiotics, disinfectant chemicals and to phagocytosis and other components of the innate and adaptive inflammatory defense system of the body. It is known, for example, that persistence of staphylococcal infections related to foreign bodies is due to biofilm formation. Likewise, chronic Pseudomonas aeruginosa lung infections in cystic fibrosis patients are caused by biofilm growing mucoid strains. Gradients of nutrients and oxygen exist from the top to the bottom of biofilms and the bacterial cells located in nutrient poor areas have decreased metabolic activity and increased doubling times. These more or less dormant cells are therefore responsible for some of the tolerance to antibiotics. Biofilm growth is associated with an increased level of mutations. Bacteria in biofilms communicate by means of molecules, which activates certain genes responsible for production of virulence factors and, to some extent, biofilm structure. This phenomenon is called quorum sensing and depends upon the concentration of the quorum sensing molecules in a certain niche, which depends on the number of the bacteria. Biofilms can be prevented by antibiotic prophylaxis or early aggressive antibiotic therapy and they can be treated by chronic suppressive antibiotic therapy. Promising strategies may include the use of compounds which can dissolve the biofilm matrix and quorum sensing inhibitors, which increases biofilm susceptibility to antibiotics and phagocytosis.

关键词： bacterial biofilm biofilm infection antibiotic resistance quorum sensing

Tuning beneficial calcineurin phosphatase activation to counterα-synuclein toxicity in a yeast model of Parkinson’s disease

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Neural Regeneration Research 2025年第1期20卷 199-200页

作者： Srishti Chawla Mikael molin Thomas Nystrom Institute for Biomedicine Sahlgrenska AcademyCentre for Ageing and Health-AgeCapUniversity of GothenburgGothenburgSweden Department of Life Sciences Chalmers University of TechnologyGothenburgSweden

Calcineurin(CN)is a calcium-and calmodulindependent serine/threonine that has been studied in many model organisms including yeast,filamentous fungi,plants,and *** biological functions range from ion homeostasis and virulence in lower eukaryotes to T-cell activation in humans by human nuclear factors of activated *** is a heterodimeric protein consisting of a catalytic subunit,calcineurin A(Cna1p),which contains an active site with a dinuclear metal center,and a regulatory Ca^(2+) binding subunit called calcineurin B(Cnb1p)required to activate *** calcineurin B subunit has been highly conserved through evolution:For example,the mammalian calcineurin B shows 54%identity with calcineurin B from Saccharomyces cerevisiae.

关键词： activation dinuclear conserved

Conductivity improvement of Ce_(0.8)Gd_(0.2)O_(1.9) solid electrolyte

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Journal of Rare Earths 2009年第4期27卷 655-660页

作者： Sebastian molin Maria Gazda Piotr Jasinski Faculty of Electronics Telecommunications and Informatics Gdansk University of Technology ul.Narutowicza 11/12 80-952 Gdansk Poland Faculty of Applied Physics and Mathematics Gdansk University of Technology ul.Narutowicza 11/12 80-952 Gdansk Poland

Solid oxide fuel cells based on doped cefia electrolytes offer operating temperatures of -600℃. During recent years much atten- tion was aimed at successful powder preparation with high sinter activity and high conductivity. The properties of ceria electrolyte are very sensitive to impurities introduced during powder and electrolyte fabrication. One of the most successful and commercially available processes for the production of clean powders is based on the addition of several percent metallic cations that will react with impurities and segregate into the triple points of grain boundaries. In this work the results obtained from doping of CGO20 by 2% Ca and prepared by different routes were presented. The way of introducing Ca seemed to play an important role.

关键词： rare earth solid elecllolyte electrical properties impedance spectroscopy fuel cell solid oxide fuel cells (SOFC)

Quantum Group Construction of Non-standard R-matrix for Yang-Baxter Equation

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Chinese Physics Letters 1991年第10期8卷 495-498页

作者： GE molin SUN Changpi XUE Kang Theoretical Physics Division Nanlrai Institute of MathematicsTianjin 300071 Department of Physics Northeast Normal UniversityChangchun 130024

By taking the concept of weight conservation into account,new solations of Yang-Baxter equation without spectral parameter are obtained through the non-standard A-matrix on the feensorial space V^(1/2) (j≠1/2)in terms of the irreducible representation of the quantum universal enveloping algebra SLq(2).The non-standard R-matrix J?1/21 is obtained in an explicit form for j=1.

关键词： matrix algebra irreducible

Separating polydisperse particles using electrostatic precipitators with wire and spiked-wire discharge electrode design

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Particuology 2018年第3期16卷 10-17页

作者： soren Sander Steffen Gawor Udo Fritsching Process Engineering Stiftung Institut ffir Werlcstofftechnik Badgasteiner Strasse 3 28359 Bremen Germany Particles and Process Engineering University of Bremen Bibliothekstrasse 1 28359 Bremen. Germany

Numerical simulations of electrostatic precipitators featuring wire and spiked electrode designs were performed to determine particle behavior and separation efficiency. The applied-voltage mechanism that alters the flow structure of particles through ionic winds and mean electric fields are revealed. Numeri- cal studies throughout the past years have shown these structures for channel and pipe configurations. However, less attention was given to field averaging for the ni,~r-product and electric field. Our study focuses on this averaging and illustrates relevant differences between multidimensional setups concern- ~ng these fields. Turbulence was modeled using the Reynolds-averaged Navier-Stokes equations with a second-order Reynolds-stress-model closure. A high three-dimensionality of the ionic wind-induced turbulence is presented. This leads to an increase in the submicron-particle precipitation rate. The results confirm the dependence of separation efficiency on particle density and permittivity, thereby showing the advantages of spiked wires compared with wire-plate setups used in electrostatic precipitators.

关键词： Electro-hydrodynamic CFD simulation Electrostatic particle precipitation Electrode design Collection efficiency

Landing gear noise control using perforated fairings

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Acta Mechanica Sinica 2010年第2期26卷 159-174页

作者： K. Boorsma X. Zhang N. molin University of Southampton Southampton SO171BJ UK Airbus Operations S.A.S 316 Route de Bayonne 31060 Toulouse Cedex 03 France

Landing gears of commercial aircraft make an important contribution to total aircraft noise in the approach configuration. Using fairings to shield components from high speed impingement reduces noise. Furthermore, perforating these fairings has been confirmed by flight tests to further enable noise reduction. Following an earlier fundamental study of the application of perforated fairings, a study has been performed to investigate and optimize the benefits of bleeding air through landing gear fairings. By means of wind tunnel tests, an aerodynamic and acoustic survey has been performed on a simplified generic main landing gear to explore the influence of （perforated） fairings on the lower part of the gear. The results show that for this specific case, the application of impermeable fairings reduces noise in the mid- and high frequency range by shielding sharp edged components from high velocity impingement. However, below 1 kHz the noise is shown to increase significantly. Application of the perforations is shown to diminish this low frequency increase whilst maintaining the reduction in the mid- and high frequency range. The aerodynamic and acoustic measurements point in the direction of the separated flow of the fairings interacting with the downstream gear components responsible for the low frequency noise increase. Bleeding of the air through the fairings reduces the large scale turbulence in the proximity of these components and hence diminishes the low frequency noise increase.

关键词： Landing gear · Aerodynamics · Acoustics

Dynamic flowsheet simulation of re-entrainment from particle layers formed inside electrostatic precipitators

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Particuology 2020年第6期18卷 41-47页

作者： soren Sander Udo Fritsching Particles and Process Engineering University of BremenBibliothekstrasse 128359 BremenGermany Process Engineering Leibniz-lnstitutfiir Werkstofforientierte Technologien-IWTBadgasteiner Strasse 328359 BremenGermany

Electrostatic precipitators clean away the particulate matter of exhaust gases in manifold industrial *** studies of particle separation in the size range of several 100 nm to 25μm is of particular interest for the prediction of precipitation efficiencies and *** typically cover the transport of particles towards walls of the ***,no model yet covers the possible re-entrainment of particles from layers formed at the walls back into the gas *** study presents the implementation of a new time-resolving model for electrostatic precipitation utilizing a re-entrainment *** data support the results of *** model uses a statistical approach based on properties of the particulate layer forming at the precipitator *** model is used for the analysis of the redispersion of particles in a laboratory-scale electrostatic precipitator(Sander,Gawor,&Fritsching,2018).Results show reduced precipitation efficiencies for particles larger than 5μm as particles have higher kinetic impact energies and lower bounding energy at the layer *** dynamics reveal a steady-state behavior of the separation for CaCO3(limestone,trademark"Ulmer WeissR")while Al2O3(trademark"Pural NFR")precipitation is affected by layer buildup at the walls increasing over several minutes.

关键词： Electrostatic precipitator Flow sheet model Redispersion and re-entrainment Gas cleaning Particle layer

Liver cirrhosis and arterial hypertension

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World Journal of Gastroenterology 2006年第5期12卷 678-685页

作者： Jens H Henriksen soren Moller Department of Clinical Physiology 239University of CopenhagenH:S Hvidovre HospitalCopenhagenDenmark

Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems （renin-angiotensin-aldosterone system, sympathetic nervous system, release of vasopressin）, and resistance to vasopressors. The vasodilatory state is mediated through adrenomedullin, calcitonin generelated peptide, nitric oxide, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective （although relative） counterbalance to increased arterial blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension （essential, secondary） may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most likely includes the combination of vasodilatation and vasoconstriction in parallel.

关键词： Arterial compliance Central vascular filling Chyperdynamic circulation Kidney function, Nitric oxide Blood pressure regulation Renin-angiotensin-aldosterone system Sympathetic nervous system Vasodilatation Vasoconstriction

Product portfolio map:a visual tool for supporting product variant discovery and structuring

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Advances in Manufacturing 2014年第2期2卷 179-191页

作者： soren Ulonska Torgeir Welo Faculty of Engineering Science and Technology Norwegian University of Science and TechnologyTrondheimNorway Department of Engineering Design and Materials Norwegian University of Science and TechnologyTrondheimNorway

A fundamental criterion for reusing and continuously improving knowledge in product development is ensuring that the knowledge is explicit and *** paper is based on the situation of an engineer-to-order（ETO） manufacturing company,where historically grown product variety and related knowledge are diffuse（tacit）.Consequently,several resources are used in（re）developing derivatives of previous products rather than innovating new *** establish a more competitive configure-to-order（CTO） product strategy,product knowledge needs to be revealed,systemized,and structured,and thus made ***,product-specific knowledge and product variants have been analyzed and subsequently mapped at architectural,functional,and physical levels in one unified map and tested in the form of a proof-of-concept（POC）demonstrator with the introduced SME *** result is a product portfolio map that forms a base for defining a systemized,transparent,unified product variant overview,which can be used as a basis for implementing a cross-variant product architecture and supporting knowledge-based approaches.

关键词： Knowledge-based development(KBD) Knowledge discovery Product architecture Product portfolio mapping