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A Simple, Fast and Stabilized Flowing Finite Volume Method for Solving General Curve Evolution Equations

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Communications in Computational Physics 2010年第1期7卷 195-211页

作者： Karol Mikula Daniel Sevcovic Martin Balazovjech Department of Mathematics Slovak University of TechnologyRadlinskeho 1181368 BratislavaSlovak Republic Department of Applied Mathematics and Statistics Comenius University84248 BratislavaSlovak Republic

A new simple Lagrangian method with favorable stability and efficiencyproperties for computing general plane curve evolutions is presented. The methodis based on the flowing finite volume discretization of the intrinsic partial differentialequation for updating the position vector of evolving family of plane curves. A curvecan be evolved in the normal direction by a combination of fourth order terms relatedto the intrinsic Laplacian of the curvature, second order terms related to the curva-ture, first order terms related to anisotropy and by a given external velocity field. Theevolution is numerically stabilized by an asymptotically uniform tangential redistri-bution of grid points yielding the first order intrinsic advective terms in the governingsystem of equations. By using a semi-implicit in time discretization it can be numer-ically approximated by a solution to linear penta-diagonal systems of equations (inpresence of the fourth order terms) or tri-diagonal systems (in the case of the secondorder terms). Various numerical experiments of plane curve evolutions, including, inparticular, nonlinear, anisotropic and regularized backward curvature flows, surfacediffusion and Willmore flows, are presented and discussed.

关键词： Geometric partial differential equations evolving plane curves mean curvature flow anisotropy Willmore flow surface diffusion finite volume method semi-implicit scheme tangen-tial redistribution

Circulating tumor cells and drug history in primary breast cancer patients

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Cancer Drug Resistance 2020年第1期3卷 98-109页

作者： Silvia Jurisova Marián Karaba Gabriel Minarik Juraj Benca Tatiana Sedlackova Daniela Manasova Katarina Kalavska Daniel Pindak Jozef Mardiak Michal Mego nd Department of Oncology Faculty of MedicineComenius UniversityBratislava 83310Slovakia National Cancer Institute Bratislava 83310Slovakia Slovak Medical University Bratislava 83101Slovakia Institute of Molecular Biomedicine Faculty of MedicineComenius UniversityBratislava 83172Slovakia Department of Medicine St.Elizabeth UniversityBratislava 81250Slovakia

Aim:Different types of chronic medication may affect breast cancer *** tumor cells(CTCs)play an important role in cancer metastasis *** is no evidence of how chronic medication affects CTCs and breast cancer *** aim of this study was to evaluate association between chronic medication and CTCs in patients with primary breast ***:This study involved 414 patients with stage I-III primary breast *** drug history was collected from patients’medical records and included all drugs that were prescribed for patients over at least the last 6 months prior to CTCs *** were detected using a quantitative real-time polymerase chain reaction(qRT-PCR)-based method at the time of breast ***:There was no association between CTCs,including their different subpopulations and chronic *** medication using angiotensin-converting-enzyme inhibitors(ACEi),metformin,and insulin were associated with inferior disease-free survival(HR=0.49,95%CI 0.26-0.94,P=0.007 for ACEi;HR=0.27,95%CI 0.08-0.91,P<0.001 for metformin;and HR=0.12,95%CI 0.01-2.91,P<0.001 for insulin)and this was most pronounced in patients with epithelial to mesenchymal transition(CTC_EMT)*** multivariate analysis,chronic administration of metformin and/or insulin was an independent predictor of inferior ***:Our findings show that there was no association between chronically used medication and CTCs in primary breast cancer ***,administration of ACEi,metformin,and/or insulin could negatively affect prognosis of patients with CTC_EMT.

关键词： Circulating tumor cells chronic medication epithelial-to-mesenchymal transition early breast cancer

Plasma activated water prepared by different plasma sources:physicochemical properties and decontamination effect on lentils sprouts

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Plasma Science and Technology 2022年第1期24卷 108-117页

作者： Veronika MEDVECKA Samuel OMASTA Matej KLAS Silvia MOSOVSKA Stanislav KYZEK Anna ZAHORANOVA Department of Experimental Physics Faculty of MathematicsPhysics and InformaticsComenius UniversityMlynska Dolina FI84248 BratislavaSlovakia Department of Nutrition and Food Quality Assessment Faculty of Chemical and Food TechnologySlovak University of TechnologyRadlinskeho 981107 BratislavaSlovakia Department of Genetics Faculty of Natural SciencesComenius UniversityIlkovicova 6Mlynska dolina84215 BratislavaSlovakia

The pulsed corona discharge(CD)generated in contact with water and directly in water,and high-power air plasma jet(APJ)were studied for production of plasma activated water(PAW).The changes of physical(pH,redox potential,conductivity,temperature)and chemical(peroxides,nitrites,nitrates concentrations)properties of treated water were *** comparison of CD generated in gas/water interface and underwater configuration in the same system showed that the interaction of reactive oxygen and nitrogen species formed in ambient air in gas/water system induces different chemical processes,leading to lower pH,higher oxidation-reduction potential(ORP)and higher conductivity of PAW than in underwater *** yield of peroxide was observed in both *** PAW prepared by APJ exhibits high concentration of nitrites and nitrates according to supplied energy,and related significant decrease of pH and increase of ORP and conductivity after *** antimicrobial effect of PAW prepared by CD and plasma jet on lentils sprouts was studied in different treatment and washing *** APJ appears to have great efficacy on water activation resulted in strong decontamination *** PAW treated by APJ for 10 min led to bacterial reduction from initial 8.3 to 5.9 and 4.0 log10 CFU g^(-1)after 10 and 30 min of washing,respectively.

关键词： plasma activated water physicochemical properties air plasma jet underwater plasma decontamination effect

Effect of Osmotic Stress in Early Stages of Ontogenesis on Root Respiration, Growth, Sugar Content,and Cell Injury in Maize Seedlings Differing in Drought Sensitivity

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Journal of Integrative Plant Biology 2006年第7期48卷 814-822页

作者： Lukás, Kolarovic Miroslava Luxová Peter Valentovic Institute of Botany Slovak Academy of Sciences Dubravská cesta 14 Bratislava 84523 Slovakia

Cultivars of maize （Zea mays L.） with different sensitivity to drought were exposed to 0.3 mol/L sorbitol （-1.4 MPa water potential） for 24 h. Exposure to water deficiency significantly reduced the growth of both shoots （coleoptile and hypocotyl） and roots. Shoot growth was inhibited more than the growth of roots. Osmotic stress enhanced accumulation of soluble sugars. Electrolyte leakage, a cell injury index, was slightly increased after 0.3 mol/L sorbitoh Respiration was measured in the presence and absence of 2,6-dlchloro-phenol indophenoh 2,6-Dichloro-phenol indophenol did not influence respiration rates, because statistically equal results were observed under both conditions. Total respiration （VT） decreased after osmoticum treatment. There were no significant differences in the VT among the cultlvars analysed. The decrease In VT was caused by a decline In the activities and capacities of both cytochrome （Vcyt, Vcyt） and alternative pathway （Valt, Valt） of respiration. A high residual respiration （Vres） was observed, up to 27% of total uninhibited respiration. The result of uncoupler use clearly indicated that coupling was maintained after 24 h of osmotic stress. The recovery of the respiration rate was comparable with that of non-stressed control rates. According to these observations, no possible mltochondrial damage is expected. Water deficiency did not induce a stimulation of the alternative oxidase, so we assume that the stimulation of the alternative pathway is not related to drought stress resistance; rather, the function of the alternative pathway is to balance carbon metabolism and electron transport in a response to a changing environment.

关键词： alternative oxidase (AOX) alternative respiration 2,6-dichloro-phenol indophenol (DCPIP) maize osmotic stress sugars uncoupler.

Skeletal faunas from the Qiongzhusian of southern Shaanxi: biodiversity and lithofacies-biofacies links in the Lower Cambrian carbonate settings

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Progress in Natural Science:Materials International 2004年第1期14卷 92-97页

作者： Michael STEINER 13355 Berlin Ackerstrasse 71～76 Germany Technische Universitt Berlin Sekr.ACK 14

The Xiaoyang section, located in Zhenba County of Shaanxi Province, is important both for documenting the biodiversity of the Qiongzhusian Stage (Lower Cambrian) and for analyzing lithofacies biofacies links in carbonate depositing environments on the Yangtze Platform. The skeletal fossils from the Xihaoping Member, including linguloid valves, cambroclavid and chancelloriid sclerites, genal and occipital spines of polymerid trilobites, and tubular fossils, are described here as the Eoobolus Cambroclavus fauna, which mainly occurred in peritidal environments. The fossils from the argillaceous limestones of the lower Shuijingtuo Formation, containing lingulate brachiopods, eodiscoid trilobites, bivalved arthropods, microdictyoniid sclerites and siliceous sponge spicules, are regarded as the Palaeobolus Hupeidiscus Kunmingella fauna, which presumably lived in subtidal or deeper water environments. The faunal diversity in the Xihaoping Member is lower than that in the lower Shuijingtuo Formation. The investigations of the skeletal fossil assemblages from carbonate lithofacies in southern Shaanxi will significantly contribute to a detailed documentation of the biodiversity during the Qiongzhusian interval on the Yangtze Platform and add new knowledge on the Cambrian bioradiation.

关键词： skeletal fauna Xihaoping Member Shuijingtuo Formation Lower Cambrian Shaanxi

Support points for families of univalent mappings on bounded symmetric domains

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Science China Mathematics 2020年第12期63卷 2379-2398页

作者： Hidetaka Hamada Gabriela Kohr Faculty of Science and Engineering Kyushu Sangyo UniversityFukuoka 813-8503Japan Faculty of Mathematics and Computer Science Babecs-Bolyai UniversityCluj-Napoca 400084Romania

In this paper,we study some extremal problems for the family Sg^0(BX)of normalized univalent mappings with g-parametric representation on the unit ball BX of an n-dimensional JB*-triple X with r≥2,where r is the rank of X and g is a convex(univalent)function on the unit disc U,which satisfies some natural *** obtain sharp coefficient bounds for the family Sg^0(BX),and examples of bounded support points for various subsets of Sg^0(BX).Our results are generalizations to bounded symmetric domains of known recent results related to support points for families of univalent mappings on the Euclidean unit ball B^n and the unit polydisc U^n in C^*** questions will be also ***,we point out sharp coefficient bounds and bounded support points for the family Sg^0(B^n)and for special compact subsets of Sg^0(B^n),in the case n≥2.

关键词： bounded symmetric domain Carathéodory family g-Loewner chain parametric representation starlike mapping support point

Neoadjuvant radiotherapy for rectal cancer management

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World Journal of Gastroenterology 2019年第33期25卷 4850-4869页

作者： Gerard Feeney Rishabh Sehgal Margaret Sheehan Aisling Hogan Mark Regan Myles Joyce Michael Kerin Department of General/Colorectal Surgery Galway University HospitalGalway H91 YR71Ireland Department of Histopathology Galway University HospitalGalway H91 YR71Ireland

Thirty per cent of all colorectal tumours develop in the *** location of the rectum within the bony pelvis and its proximity to vital structures presents significant therapeutic challenges when considering neoadjuvant options and surgical *** patients with early rectal cancer can be adequately managed by surgery ***,a significant proportion of patients with rectal cancer present with locally advanced disease and will potentially benefit from down staging prior to *** therapy involves a variety of options including radiotherapy,chemotherapy used alone or in *** radiotherapy in rectal cancer has been shown to be effective in reducing tumour burden in advance of curative *** gold standard surgical rectal cancer management aims to achieve surgical removal of the tumour and all draining lymph nodes,within an intact mesorectal package,in order to minimise local *** is critically important that all rectal cancer cases are discussed at a multidisciplinary meeting represented by all relevant ***-operative staging including CT thorax,abdomen,pelvis to assess for distal disease and magnetic resonance imaging to assess local involvement is *** radiology and MDT discussion are integral in identifying patients who require neoadjuvant *** Neoadjuvant radiotherapy is potentially beneficial it may also result in morbidity and thus should be reserved for those patients who are at a high risk of local failure,which includes patients with nodal involvement,extramural venous invasion and threatened circumferential *** aim of this review is to discuss the role of neoadjuvant radiotherapy in the management of rectal cancer.

关键词： Rectal cancer Neoadjuvant therapy Low anterior resection syndrome Stoma Transanal endoscopic microsurgery Trans-anal total mesorectal excision Robotic surgery Watch and wait

Improvement of PCR reaction conditions for site-directed mutagenesis of big plasmids

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第4期13卷 244-247页

作者： Bogdan MUNTEANU Mario BRAUN Kajohn BOONROD RLP AgroScience GmbH AlPlanta-Institute for Plant ResearchBreitenweg 71D-67435 NeustadtGermany

QuickChange mutagenesis is the method of choice for site-directed mutagenesis （SDM） of target sequences in a plasmid. It can be applied successfully to small plasmids （up to 10 kb）. However, this method cannot efficiently mutate bigger plasmids. Using KOD Hot Start polymerase in combination with high performance liquid chromatography （HPLC） purified primers, we were able to achieve SDM in big plasmids （up to 16 kb） involving not only a single base change but also multiple base changes. Moreover, only six polymerase chain reaction （PCR） cycles and 0.5μI of polymerase （instead of 18 PCR cycles and 1.0 μI of enzyme in the standard protocol） were sufficient for the reaction.

关键词： Site-directed mutagenesis (SDM) Mutant Plasmid

Pulse electrodecontamination of the surface of steel

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Nuclear Science and Techniques 2004年第5期15卷 312-316页

作者： LU Chun-Hai SUN Ying LANG Ding-Mu ZHU Xiao-Hong FEI Yue GAO Ge XIE Wei-Hua China Academy of Engineering Physics.P.O.Box919-71 Mianyang621900

Electrochemical decontamination is a new technology for removing heavy metal from the surface of conductor. The optimum parameters are explored by studying the working mode with pulsed power supply. For test- ing and verifying advantages of this technology, we have made an experment on removing uranium pollution from metal surface of a polluted equipment, which has been used for over 20 years. A good decontamination result has been obtained even if a lower current density is supplied.

关键词：铀污染净化核能利用电化学