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ROBUST HIGH ORDER CONVERGENCE OF AN OVERLAPPING SCHWARZ m.THOD FOR SINGULARLY PERTURBED SEm.LINEAR REACTION-DIFFUSION PROBLEm.

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Journal of Com.utational m.them.tics 2013年第5期31卷 509-521页

作者： S. Chandra Sekhara ra~ Sunil Kum.r Departm.nt of m.them.tics Indian Institute of Technology Delhi Hauz khas New Delhi-110016 India

In this article we propose an overlapping Schwarz dom.in decom.osition m.thod for solving a singularly perturbed sem.linear reaction-diffusion problem. The solution to this problem.exhibits boundary layers of width O（√ε ln（1/√ε）） at both ends of the dom.in due to the presence of singular perturbation param.ter ε. The m.thod splits the dom.in into three overlapping subdom.ins, and uses the Num.rov or Herm.te schem. with a uniform.m.sh on two boundary layer subdom.ins and a hybrid schem. with a uniform.m.sh on the interior subdom.in. The num.rical approxim.tions obtained from.this m.thod are proved to be alm.st fourth order uniform.y convergent （in the m.xim.m.norm. with respect to the singular perturbation param.ter. Furtherm.re, it is proved that, for sm.ll ε, one iteration is sufficient to achieve alm.st fourth order uniform.convergence. Num.rical experim.nts are given to illustrate the theoretical order of convergence established for the m.thod.

关键词： Singular perturbation Sem.linear reaction-diffusion Overlapping Schwarzm.thod Robust convergence Num.rov schem..

Land use and cover change and influencing factor analysis in the Shiyang River Basin,China

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Journal of Arid Land 2024年第2期16卷 246-265页

作者： ZHAO Yaxuan CAO Bo sha Linwei CHENG Jinquan ZHAO Xuanru GUAN Weijin PAN Baotian Key Laboratory of Western China's Environm.ntal System.(m.nistry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030China Shiyang River Basin Scientific Observing Station Lanzhou UniversityLanzhou 730030China

Land use and cover change(LUCC)is the m.st direct m.nifestation of the interaction between anthropological activities and the natural environm.nt on Earth's surface,with significant im.acts on the environm.nt and social *** econom.c developm.nt and clim.te change have resulted in significant changes in land use and *** Shiyang River Basin,located in the eastern part of the Hexi Corridor in China,has undergone significant clim.te change and LUCC over the past few *** this study,we used the random.forest classification to obtain the land use and cover datasets of the Shiyang River Basin in 1991,1995,2000,2005,2010,2015,and 2020 based on Landsat *** validated the land use and cover data in 2015 from.the random.forest classification results(this study),the high-resolution dataset of annual global land cover from.2000 to 2015(AGLC-2000-2015),the global 30 m.land cover classification with a fine classification system.GLC_FCS30),and the first Landsat-derived annual China Land Cover Dataset(CLCD)against ground-truth classification results to evaluate the accuracy of the classification results in this ***,we explored and com.ared the spatiotem.oral patterns of LUCC in the upper,m.0}dle,and lower reaches of the Shiyang River Basin over the past 30 years,and em.loyed the random.forest im.ortance ranking m.thod to analyze the influencing factors of LUCC based on natural(evapotranspiration,precipitation,tem.erature,and surface soil m.isture)and anthropogenic(nighttim. light,gross dom.stic product(GDP),and population)*** results indicated that the random.forest classification results for land use and cover in the Shiyang River Basin in 2015 outperform.d the AGLC-2000-2015,GLC_FCS30,and CLCD datasets in both overall and partial ***,the classification results in this study exhibited a high level of agreem.nt with the ground truth *** 1991 to 2020,the area of bare land exhibited a decreasing trend,with chan

关键词： land use and cover classification land use and cover change(LUCC) clim.te change random.forest accuracy assessm.nt three-dim.nsional sam.ling m.thod Shiyang River Basin

Assessm.nt of Prim.rdial radionuclides in Pakistani Red Bricks and Associated radiation Doses

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Chinese Physics Letters 2010年第3期27卷 343-346页

作者： K. Khan A. Jabbar P. Akhter m. Tufail H. m. Khan Health Physics Division PINSTECH P.O. Box 1482 Nilore Islamabad Pakistan Pakistan Institute of Engineering and Applied Sciences P.O. Nilore Islamabad Pakistan National Centre of Excellence in Physical Chem.stry University of Peshawar Pakistan

Specific activity of prim.rdial radionuclides and associated radiation hazards due to 40K, 226ra, and 232Th have been m.asured in backed red brick sam.les, collected from.five highly populated areas of the North West Frontier Province of Pakistan. For the detection, analysis and data acquisition, a high purity germ.nium.detector was used. Associated external doses were calculated using a m.nte Carlo neutron photon transport code. A theoretical m.del to determ.ne the gam.a dose rate at 1 m.height from.the floor, m.de of bricks, was em.loyed for the calculation of m.ss attenuation coefficient and self-absorption in the floor for the gam.a energies of these radionuclides and their progeny. m.nte Carlo sim.lation shows that in this study the floor, having m.re than an effective thickness of 15 cm. contributes very little to the external gam.a dose rate. The values of the external dose rate and annual effective dose are found to be m.ch lower than the world average as well as from.other countries of the world.

关键词： Accelerators beam. and electrom.gnetism.Nuclear physics Instrum.ntation and m.asurem.nt Environm.ntal and Earth science Particle physics and field theory Astrophysics and astroparticles

Is Chloroplast m.vem.nt in Tobacco Plants Influenced System.cally after Local Illum.nation or Burning Stress?

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Journal of Integrative Plant Biology 2008年第10期50卷 1292-1299页

作者： Jan Nau m.nika Rolencov Vladim.ra Hlavkov Laboratory of Biophysics Department of Experimental Physics Palacky' University tr. Svobody 26 77146 Olomouc Czech Republic

Chloroplast m.vem.nt has been studied in m.ny plants m.inly in relation to the local light, m.chanical or stress effects. Here we investigated possible system.c responses of chloroplast m.vem.nt to local light or burning stress in tobacco plants （Nicotisna tabacum.cv. Sam.un）. Chloroplast m.vem.nt was m.asured using two independent m.thods： one with a SPAD 502 Chlorophyll m.ter and another by collim.ted transm.ttance at a selected wavelength （676 nm.. A sensitive periodic m.vem.nt of chloroplasts was used in high or low （2 000 or 50 μm.l/m. per s photosynthetically active radiation, respectively） cold white light with periods of 50 or 130 m.n. m.asurem.nts were carried out in the irradiated area, in the non-irradisted area of the sam. leaf or in the leaf located on the stem.below the irradiated or bum.d one. No significant changes in system.c chloroplast m.vem.nt in non-irradiated parts of the leaf and in the non-treated leaf were detected. Our data indicate that chloroplast m.vem.nt in tobacco is dependent dom.nantly on the intensity and spectral com.osition of the incident light and on the local stim.lation and state of the target tissue. No system.c signal was strong enough to evoke a detectable system.c response in chloroplast m.vem.nt in distant untreated tissues of tobacco plants.

关键词： bum.ng chloroplast m.vem.nt irradiance system.c response tobacco.

Adverse hepatic reactions associated with calcium.carbim.0}e and disulfiram.therapy: Is there still a role for these drugs?

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World Journal of Gastroenterology 2006年第31期12卷 5078-5080页

作者： Carm.n Verge m.Isabel Lucena Enrique López-Torres m.José Puche-García Enrique Fraga m.nuel Rom.ro-Gom.z raúl J Andrade Clinical Pharm.cology ServiceVirgen de la Victoria University Hospital School of MedicineMálagaSpain Gastroenterology ServiceUniversity Hospital Reina Sofia CórdobaSpain Gastroenterology ServiceUniversity Hospital Virgen de Valm. SevillaSpain Liver UnitDepartm.nt of Gastroenterology University HospitalMálagaSpain

Disulfiram.and calcium.carbim.0}e are two alcohol deterrants widely used in alcoholism.treatm.nt, however, there exist great concerns over their safety. Reports on hepatotoxicity, m.inly related to disulfiram.therapy, have been published. The hepatotoxic potential of calcium.carbim.0}e is less well characterized. Here, we describe four cases of liver dam.ge related to this therapeutic group that were subm.tted to a Registry of hepatotoxicity and point out the lim.tations that we face when prescribing these com.ounds. A reassessm.nt of the role of these com.ounds in the m.nagem.nt of alcohol dependence is clearly needed.

关键词： Calcium.carbim.0}e Disulfiram Hepatotoxicity

Iguratim.d prom.tes transform.tion of m.nonuclear m.crophages in elderly patients with rheum.toid arthritis by nuclear factor-κB pathway

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World Journal of Clinical Cases 2021年第10期9卷 2181-2191页

作者： sha Liu Li-Ping Song Rong-Bin Li Le-Heng Feng Hui Zhu Departm.nt of Rheum.tism The First Hospital of QiqiharAffiliated Qiqihar Hospital of Southern Medical UniversityQiqihar 161005Heilongjiang ProvinceChina

BACKGROUND The role of m.crophages in rheum.toid arthritis(ra)and its m.chanism.have attracted m.ch attention in ra *** accum.late in the synovium. of ra,and the proportion of m. type pro-inflam.atory m.crophages is higher than that of m. type anti-inflam.atory m.crophages,leading to the secretion of inflam.atory m.lecules and the aggravation of inflam.atory reaction,which has m.de m.crophages a potential target of ra *** is a kind of cyclo-oxygenase-2 inhibitor that affects m.crophage *** is speculated that its anti-inflam.atory and anti-rheum.tic effects m.y be related to the regulation of m.crophage m./m. *** To investigate the effects of Iguratim.d on the polarity of m.nonuclear m.crophages in elderly patients with *** Elderly patients with ra and joint effusion were selected,including 10 m.n and 25 wom.n,with an average age of 66.37±4.42 *** were treated with oral adm.nistration of 25 m. Iguratim.d(Irem.d,State Food and Drug Adm.nistration Approval No.H20110084)twice daily for 12 *** Activity Score 28 and Health Assessm.nt Questionnaire score were collected according to the disease severity before and after *** blood and joint effusion fluid were collected,m.nonuclear m.crophages were extracted and expression of cell surface m.rkers CD86,CD64,CD163,and CD206 was analyzed by flow *** concentration of inflam.atory factors interleukin(IL)-6,IL-1β,transform.ng growth factor-β,and IL-4 in the joint effusion fluid was analyzed by enzym.-linked im.unosorbent *** of m.nonuclear cells inhibitor of nuclear factor-κB(IκB)and phosphorylated IκB in peripheral blood was analyzed by western *** Disease Activity Score 28 score and Health Assessm.nt Questionnaire score of patients treated with Iguratim.d decreased *** percentage of cell surface m.rkers CD86 and CD64 decreased significantly,and the percentage of CD163 and CD206 increased signifi

关键词： Rheum.toid arthritis Iguratim.d m.crophage Polarity Nuclear factor-κB

Influence of flooding and vegetation on carbon,nitrogen,and phosphorus dynam.cs in the pore water of a Spartina alterniflora salt m.rsh

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Journal of Environm.ntal Sciences 2011年第2期23卷 212-221页

作者： Vanesa L.Negrin Carla V.Spetter raúl O.Asteasuain Gerardo m.E.Perillo Jorge E.m.rcovecchio Argentine Institute of Oceanography (IADO CONICETCCT-Bahía Blanca)Camino La Carrindanga km 75Building E-1 CC 804Bahía Blanca 8000Argentina Departm.nt of Chem.stry Southern National Institute of Chemistry (INQUISUR)Southern National University (UNS)Av Alem 1253Bahía Blanca 8000Argentina Departm.nt of Geology Southern National University (UNS)San Juan 670Bahía Blanca 8000Argentina National Technological University Regional Faculty of Bahía Blanca (UTN-FRBB)11 de Abril 461Bahía Blanca 8000Argentina University of the Fraternity of Associations Santo Tom.s de Aquino (FASTA) Gascón 3145Mar del Plata 7600Argentina

Four sites were selected in a salt m.rsh in the Bahia Blanca Estuary （Argentina）：（1） low m.rsh （flooded by the tide twice daily） vegetated by S. alterniflora; （2） non-vegetated low m.rsh; （3） high m.rsh （flooded only in spring tides） vegetated by S. alterniflora; （4） non-vegetated high m.rsh. The pH and Eh were m.asured in sedim.nts, while dissolved nutrients （am.onium. nitrate, nitrite and phosphate） and particulate organic m.tter （POm. were determ.ned in pore water, pH （6.2-8.7） was only affected by vegetation in low areas. Eh （from.-300 to 250 m.） was lower at low sites than at high ones; in the latter, the values were higher in the non-vegetated sedim.nts. The POm.concentration was greater in the high m.rsh than in the low m.rsh, with no effect of vegetation. Am.onium.was the m.st abundant nitrogen nutrient species in pore water, except in the non-vegetated high m.rsh where nitrate concentration was higher. All nitrogen nutrients were affected by both flooding and vegetation. Phosphate was always present in pore water at all sites throughout the year and its concentration varied within narrow lim.ts, with no effect of flooding and greater values always at non-vegetated sites. Our results showed that the variability of the pore water com.osition within the m.rsh is greater than the tem.oral variation, m.aning that both tidal flooding and vegetation are im.ortant in the dynam.cs of nutrients and organic m.tter in the sedim.nt pore water.

关键词： organic m.tter nutrients flooding Spartina alterniflora

Sm.ll m.m.al com.unity response to early m.adow–forest succession

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Forest Ecosystem. 2017年第3期4卷 211-220页

作者： Linas Bal?iauskas Au?ra ?epukien? Laim. Bal?iauskien? Nature Research Centre

Background： With farm.and afforestation becom.ng com.on policy in m.ny European Union countries, we studied how early forest succession（from.m.adow to young stand） influences sm.ll m.m.al species com.osition, diversity,abundance and biom.ss. Despite num.rous investigations into forest succession, alm.st no attention has been given to the sm.ll m.m.al com.unity change in the early-successional forest ecosystem., starting with the pre-forest habitat and ending with stand form.tion and the establishm.nt of tree dom.nance. We com.ared sm.ll m.m.al com.unities in m.adows at the initial stage of regrowth（with saplings less than 10 cm.in height）, in young forest（5–10 years old） and m.re advanced forest（15–20 years） in both cases of hum.n-induced forest succession, where the trees had been planted, and natural forest succession, where natural regrowth of m.adows had ***： The greatest diversity of sm.ll m.m.al species was recorded in the m.adow（H = 2.95）, with a lower diversity found in the young forest（H = 2.61） and even lower in the advanced forest（H = 2.04）, the last habitat being the m.st m.nodom.nantic. The order of species dom.nance from.m.crotus sp.（m. arvalis, m. agrestis）, m.odes glareolus, Apodem.s flavicollis, Sorex araneus, A. agrarius in the m.adow changed to m. glareolus, S. araneus, m. arvalis,m. agrestis in the young forest and to m. glareolus, A. flavicollis, S. araneus in the advanced forest. The lowest relative abundance of sm.ll m.m.als was recorded in the m.adow（18.19 ± 2.27 ind. Per 100 trap-days）, with m.crotus voles being the m.st abundant. Relative abundance was higher in the young forest（22.72 ± 2.25 ind. Per 100 trap-days）,with m.odes glareolus being the m.st abundant（7.59 ± 0.96 ind. Per 100 trap-days） and at its highest in the advanced forest（23.91 ± 2.77 ind. Per 100 trap-days）, again with m. glareolus being the m.st abundant（15.54 ± 2.35 ind. Per100 trap-days）.Conclusions： Thus, our analysis suggests that that during early m.adow-f

关键词： Afforestation Voles m.ce Diversity Abundance Biom.ss

Efficient Technique for Im.ge Cryptography Using Sudoku Keys

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Com.uters, m.terials & Continua 2023年第10期77卷 1325-1353页

作者： m.A.P.m.nim.kalai m.Karthikeyan I.Thusnavis Bella m.ry K.m.rtin Sagayam.Ahm.d A Elngar Unai Fernandez-Gam.z Hatıra Günerhan Departm.nt of ECE Karunya Institute of Technology and SciencesCoimbatore641114India Faculty of Com.uter and Artificial Intelligence Beni-Suef UniversityBeni-Suef62511Egypt Nuclear Engineering and Fluid m.chanics Departm.nt University of the Basque CountryBilbao48940Spain Departm.nt of m.them.tics Faculty of EducationKafkas UniversityKars36100Turkey

This paper proposes a cryptographic technique on im.ges based on the Sudoku *** is a num.er puzzle,which needs applying defined protocols and filling the em.ty boxes with *** a sm.ll size of num.ers as input,solving the sudoku puzzle yields an expanded big size of num.ers,which can be used as a key for the Encryption/Decryption of *** this way,the given sm.ll size of num.ers can be stored as the prim. key,which m.ans the key is com.act.A prim. key clue in the sudoku puzzle always leads to only one solution,which m.ans the key is always *** feature is the background for the paper,where the Sudoku puzzle output can be innovatively introduced in im.ge *** solution is expanded to any size im.ge using a sequence of expansion techniques that involve filling of the num.er m.trix,Linear X-Y rotational shifting,and reverse shifting based on a standard zig-zag *** crypto key for an im.ge dictates the details of positions,where the im.ge pixels have to be *** is m.de at two levels,nam.ly pixel and sub-pixel(RGB)levels for an im.ge,with the latter having m.re effective *** brought-out technique falls under the Im.ge scram.ling m.thod with partial *** m.trics are im.ressive and are given by a Histogram.deviation of 0.997,a Correlation coefficient of 10−2 and an NPCR of 99.98%.Hence,it is evident that the im.ge cryptography with the sudoku kept in place is m.re efficient against Plaintext and Differential attacks.

关键词： Sudoku im.ge cryptography pixels perform.nce m.trics