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A Least-Squares/Fictitious Domain Method for Linear Elliptic Problems with Robin Boundary Conditions

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Communications in Computational Physics 2011年第3期9卷 587-606页

作者： roland Glowinski Qiaolin He Department of Mathematics University of HoustonHoustonTX 77204USA Institute of Advanced Study The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong Department of Mathematics The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong Department of Mathematics Sichuan UniversityChengdu 610064China

In this article,we discuss a least-squares/fictitious domain method for the solution of linear elliptic boundary value problems with Robin boundary ***Ωandωbe two bounded domains of R d such thatω⊂Ω.For a linear elliptic problem inΩ\ωwith Robin boundary condition on the boundaryγofω,our goal here is to develop a fictitious domain method where one solves a variant of the original problem on the fullΩ,followed by a well-chosen correction overω.this method is of the virtual control type and relies on a least-squares formulation making the problem solvable by a conjugate gradient algorithm operating in a well chosen control *** results obtained when applying our method to the solution of two-dimensional elliptic and parabolic problems are given;they suggest optimal order of convergence.

关键词： Least-Square methods fictitious domain methods finite element methods Robin boundary conditions

Radiofrequency ablation or percutaneous ethanol injection for the treatment of liver tumors

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World Journal of Gastroenterology 2012年第10期18卷 1003-1008页

作者： Daniel Ansari roland Andersson Department of Surgery Clinical Sciences Lund Skane University Hospital and Lund University

the liver is a common location of both primary and secondary malignancies. For unresectable liver cancer, many local ablative therapies have been developed. these include e.g., percutaneous ethanol injection (PEI), percutaneous acetic acid injection, radiofrequency ablation (RFA), cryoablation, microwave ablation, laserinduced thermotherapy, and high-intensity focused ultrasound. RFA has recently gained interest and is the most widely applied thermoablative technique. RFA allows more effective tumor control in fewer treatment sessions compared with PEI, but with a higher rate of complications. However, there are certain circumstances where PEI therapy represents a better strategy to control liver tumors than RFA, especially in situations where RFA is difficult, for example when large vessels surround the tumor. In the context of hepatocellular carcinoma (HCC), both RFA and PEI are feasible and of benefit in non-operable patients. RFA seems superior to PEI in HCC > 2 cm, and the combination of interventions may be of benefit in selected patients. Liver resection is superior to RFA for patients with HCC meeting the Milan criteria, but RFA can be employed in tumors ≤ 3 cm and where there is an increased expected operative mortality. In addition, some lines of evidence indicate that RFA and PEI can be employed as a bridge to liver transplantation. the use of RFA in colorectal liver metastases is currently limited to unresectable disease and for patients unfit for surgery. the aim of this article is to summarize the current status of RFA in the management of liver tumors and compare it to the cheap and readily available technique of PEI.

关键词： Colorectal liver metastases Hepatocellular cancer Liver resection Percutaneous ethanol injection Radiofrequency ablation

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-tALOOKOLAEI H.GHANDVAR E.JUMAEV S.KHAtIR t.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and technology Solutions Ho Chi Minh City Open University

this paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. the strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. the curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. the accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Intervention on toll-like receptors in pancreatic cancer

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World Journal of Gastroenterology 2014年第19期20卷 5808-5817页

作者： Juan Vaz roland Andersson Department of Surgery Clinical Sciences LundSkne University Hospital LundLund UniversitySE-221 85 LundSweden

Pancreatic ductal adenocarcinoma(PDA)is a devastating disease with pronounced morbidity and a high mortality *** available treatments lack convincing cost-efficiency determinations and are in most cases not associated with relevant success *** stimulation of the immune system in murine PDA models has revealed some promising *** receptors(tLRs)are pillars of the immune system that have been linked to several forms of malignancy,including lung,breast and colon *** humans,tLRs are expressed in the pancreatic cancer tissue and in several cancer cell lines,whereas they are not expressed in the normal *** the present review,we explore the current knowledge concerning the role of different tLRs associated to *** if almost all known tLRs are expressed in the pancreatic cancer microenvironment,there are only five tLRs suggested as possible therapeutic *** data points at tLR2 and tLR9 as effective tumor markers and agonists could potentially be used as *** adjuvant *** elucidation of the role of tLR3 in PDA is only in its initial *** inhibition/blockage of tLR4-related pathways has shown some promising effects,but there are still many steps left before tLR4 inhibitors can be considered as possible therapeutic ***,tLR7 antagonists seem to be potential candidates for *** of their potential in immunotherapies,all existing data indicate that tLRs are strongly involved in the pathophysiology and development of PDA.

关键词： Pancreatic cancer Pathophysiological mechanism toll-like receptor Intervention Adjuvant therapy

A Double-Phase High-Frequency traveling Magnetic Field Developed for Contactless Stirring of Low-Conducting Liquid Materials

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Computer Modeling in Engineering & Sciences 2021年第5期127卷 469-486页

作者： Xiaodong Wang Ernst roland Fautrelle Yves College of Material Science and Opto-Electronic technology University of the Chinese Academy of ScienceBeijingChina Guangwei(Zhongshan)Intelligent technology Co. Ltd.Huairou Science CityBeijingChina SIMAP/EPM Universite Grenoble AlpesGrenobleFrance

the use of low electrically conducting liquids is more and more *** is the case for molten glass,salt or slag processing,ionic liquids used in biotechnology,batteries in energy storage and *** present paper deals with the design of a new electromagnetic induction device that can heat and stir low electricallyconducting *** consists of a resistance-capacity-inductance circuit coupled with a low-conducting liquid *** device is supplied by a unique electric power source delivering a single-phase high frequency electric *** main working principle of the circuit is based on a double oscillating circuit inductor connected to the solid-state transistor *** technique,which yields a set of coupled oscillating circuits,consists of coupling a forced phase and an induced phase,neglecting the influence of the electric parameters of the loading part(i.e.,the low-conductivity liquid).It is shown that such an inductor is capable to provide a two-phase AC traveling magnetic field at high *** better understand the working principle,the present work improves a previous existing simplified theory by taking into account a complex electrical equivalent diagram due to the different mutual couplings between the two inductors and the two corresponding induced current sets.A more detailed theoretical model is provided,and the key and sensitive elements are *** on this theory,equipment is designed to provide a stirring effect on sodium chloride-salted water at 40 S/*** is shown that such a device fed by several hundred kiloHertz electric currents is able to mimic a linear motor.A set of optimized operating parameters are proposed to guide the experiment.A pure electromagnetic numerical model is *** modelling of the load is performed in order to assess the efficiency of the stirrer with a salt water *** a device can generate a significant liquid motion with both controlled flow patterns and adjus

关键词： Alternating magnetic field electromagnetic stirring low electrically conducting liquids ionic liquid

Escape to the high canopy thermal deficiency causes niche expansion in a forest-floor ant

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Insect Science 2017年第4期24卷 699-707页

作者： Bernhard Seifert Patrick Fiedler roland Schultz Senckenberg Museum of Natural History Gorlitz 02826 Gorlitz Germany Faculty of Environmental Sciences Technical University Dresden 01069 Dresden Germany

the small formicoxenine ant temnothorax saxonicus was known from about 40 localities in Central Europe nesting in anorganie substrates on floor of xerothermous forests whereas investigations of 198 tree canopies in 19 forest sites of the same region provided no indication for arboreal nesting or foraging. We present the first evidence for canopy-nesting populations of t. saxonicus on old Quercus trees in 3 sites having maximum calibrated topsoil temperatures of 17.9 ± 0.3 ℃ which were significantly （P 〈 0.007） lower than 22.8 ± 2.0 ℃ measured in 5 sites with ground-nesting populations. the thermal deficit on forest floor inhibits brood development in ground nests and caused a moving to canopy were maximum calibrated temperatures of the, now wooden, substrates are at least 26.1 ℃for the whole canopy and 30.8 ℃ in more sun-exposed spots. t. saxonieus competed here successfully with the obligatory canopy ants t. affinis and t. cortiealis. the distributional data of this rope-climbing study support former results that highest nest densities of small arboreal ants occur in temperate climate over the entire canopy mantle of single trees situated in open land or in park-like environments but occur in the top of the canopy in tree stands with high degree of canopy closure.

关键词： canopy temperature foraging distance microhabitat selection soil temper-ature soil temperature calibration temnothorax

Nano-Morphology of a Polymer Electrolyte Fuel Cell Catalyst Layer Imaging, Reconstruction and Analysis

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Nano Research 2011年第9期4卷 849-860页

作者： Simon thiele roland Zengerle Christoph Ziegler Laboratory for MEMS Applications Department of Microsystems Engineering--IMTEK University of Freiburg Georges-Koehler-Allee106 79110 Freiburg Germany

the oxygen reduction reaction （ORR） in the cathode catalyst layer （CCL） of polymer electrolyte fuel cells （PEFC） is one of the major causes of performance loss during operation. In addition, the CCL is the most expensive component due to the use of a Pt catalyst. Apart from the ORR itself, the species transport to and from the reactive sites determines the performance of the PEFC. the effective transport properties of the species in the CCL depend on its nanostructure. therefore a three-dimensional reconstruction of the CCL is required. A series of two-dimensional images was obtained from focused ion beam- scanning electron microscope （FIB-SEM） imaging and a segmentation method for the two-dimensional images has been developed. the pore size distribution （PSD） was calculated for the three-dimensional geometry. the influence of the alignment and the anisotropic pixel size on the PSD has been investigated. Pores were found in the range between 5 nm and 205 nm. Evaluation of the Knudsen number showed that gas transport in the CCL is governed by the transition flow regime. the liquid water transport can be described within continuum hydrodynamics by including suitable slip flow boundary conditions.

关键词： Cathode catalyst layer (CCL), polymer electrolyte fuel cell (PEFC), tomograph three-dimensional reconstruction

Role of CD20^+ t cells in multiple sclerosis:implications for treatment with ocrelizumab

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Neural Regeneration Research 2020年第4期15卷 663-664页

作者： Stefan Gingele thomas Skripuletz roland Jacobs Department of Neurology Hannover Medical SchoolHannoverGermany Department of Clinical Immunology&Rheumatology Hannover Medical SchoolHannoverGermany

Features of CD20^+t cells:CD20 is a membrane-spanning hosphoprotein strongly expressed on the cell surface of B lineage cells and is widely regarded as a B cell specific ***,CD20(Figure 1)is also expressed at a low level on a small subset of CD3^+t cells which therefore are sometimes referred to as CD20dimCD3^+t cells in contrast to CD20brightCD19^+B cells which represent the majority of cells expressing CD20(Hultin et al.,1993).the amount of the CD20 antigen has been assessed to be 25 to 50 times higher on CD20^+CD19^+B cells compared to CD20^+CD3^+t cells(Hultin et al.,1993).At first description of this cell population the frequency of these CD20^+t cells has been described to represent an average of 2.4%of all peripheral blood lymphocytes(50 healthy controls)(Hultin et al.,1993).

关键词： al. CD20 assessed

Buoyancy and turbulence-driven atmospheric circulation over urban areas

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Journal of Environmental Sciences 2017年第9期29卷 63-71页

作者： Yifan Fan Julian Charles roland Hunt Yuguo Li Department of Mechanical Engineering The University of Hong KongHong KongChina Department of Earth Sciences University College LondonLondonWC1E6BTUK Malaysian Commonwealth Studies Centre CambridgeCB23RFUK

In the buoyancy and turbulence-driven atmospheric circulations（BtDAC） that occur over urban areas where the approach means wind speeds are very low（less than turbulent fluctuations and typically 3 m/sec）, the surface temperatures are significantly higher than those in the external rural areas, and the atmosphere above the mixing layer is stably stratified. In this paper, the mechanisms of BtDAC formation are studied through laboratory experiments and modelling, with additional low-level inflow from external rural areas and a divergent outflow in the opposite direction in the upper part of the mixed layer. Strong turbulent plumes in the central region mix the flow between lower and higher levels up to the inversion height. there are shear-driven turbulent eddies and weaker buoyant plumes around the periphery of the urban area. As the approach flow is very weak,the recirculating streamlines within the dome restrict the ventilation, and the dispersion of pollution emitted from sources below the inversion height leading to a rise in the mean concentration. Low-level air entrained from rural areas can, however, improve ventilation and lower this concentration. this trend can also be improved if the recirculating structure of the BtDAC flow pattern over urban areas breaks down as a result of the surface temperature distribution not being symmetrical, or as the approach wind speed increases to a level comparable with the mean velocity of circulation, or（except near the equator） the urban area is large enough that the Coriolis acceleration is significant.

关键词： Urban heat island Buoyancy and turbulence-driven Eddy structures Atmospheric circulation Pollutant dispersion