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Chinese Journal of Chem.cal Engineering 2019年第7期27卷 1690-1698页

作者： Vlada B.Veljkovic Ana V. Velickovic jelena m. avramovic Olivera S. Stam.nkovic University of Nis Faculty of TechnologyBulevar oslobodenja 124Leskovac 16000Serbia Research&Developm.nt Center "Alfatec" Bulevar Nikole Tesle 63/5Nis 18000Serbia

The perform.nces of the response surface m.thodology(RSm.in connection with the Box–Behnken,face central com.osite or full factorial design(BBD,FCCD or FFD,respectively)were com.ared for the use in m.deling of the NaOH-catalyzed sunflower oil *** influence of tem.erature,catalyst loading,and ethanol-to-oil m.lar ratio(EOm.)on fatty acid ethyl esters(FAEE)content was *** three m.ltivariate strategies were efficient in the statistical m.deling and optim.zation of the influential process variables but BBD and FCCD realization involved less num.er of experim.nts,generating sm.ller costs,requiring less work and consum.ng shorter tim. than the corresponding *** three designs resulted in the sam. optim.l catalyst loading(1.25%of oil)and EOm.(12:1).The reduced two-factorinteraction(2 FI)m.dels based on the BBD and FCCD defined a range of optim.l reaction tem.erature(25℃–75℃)and 25℃,respectively while the sam. m.del based on the 33 FFD appointed 75℃.The predicted FAEE content of about 97%–98.0%was close to the experim.ntally obtained FAEE content of about 97.0%–97.6%under the optim.l reaction ***,the sim.ler BBD or FCCD m.ght successfully be applied for statistical m.deling of biodiesel production processes instead of the m.re extensive,m.re laborious and m.re expensive FFD.

关键词： Biodiesel Box-Behnken design m.del reduction Face central com.osite design Full factorial design Optim.zation

Seism.c loss assessm.nt of RC high-rise buildings designed according to Eurocode 8

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 807-824页

作者： jelena Pejovic Nina Serdar Faculty of Civil Engineering University of MontenegroBulevar Dzordza Vasingtona bbPodgorica 81000Montenegro

A probabilistic seism.c loss assessm.nt of RC high-rise(RCHR)buildings designed according to Eurocode 8 and located in the Southern Euro-m.diterranean zone is presented *** loss assessm.nt m.thodology is based on a com.rehensive sim.lation approach which takes into account ground m.tion(Gm.uncertainty,and the random.effects in seism.c dem.nd,as well as in predicting the dam.ge states(DSs).The m.thodology is im.lem.nted on three RCHR buildings of 20-story,30-story and 40-story with a core wall structural *** loss functions described by a cum.lative lognorm.l probability distribution are obtained for two intensity levels for a large set of sim.lations(NLTHAs)based on 60 Gm.records with a wide range of m.gnitude(m.,distance to source(R)and different site soil conditions(SS).The losses expressed in percent of building replacem.nt cost for RCHR buildings are *** the estim.tion of losses,both structural(S)and nonstructural(NS)dam.ge for four DSs are *** effect of different Gm.characteristics(m.R and SS)on the obtained losses are ***,the estim.ted perform.nce of the RCHR buildings are checked to ensure that they fulfill lim.t state requirem.nts according to Eurocode 8.

关键词： RC high-rise buildings seism.c loss assessm.nt loss functions nonlinear tim.-history analysis(NLTHA) cum.lative lognorm.l probability distribution random.effects Eurocode 8

Inverse-designed silicon carbide quantum.and nonlinear photonics

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Light(Science & Applications) 2023年第9期12卷 1886-1892页

作者： Joshua Yang m.lissa A.Guidry Daniil m.Lukin Kiyoul Yang jelena Vučković E.L.Ginzton Laboratory Stanford UniversityStanfordCAUSA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMAUSA

Inverse design has revolutionized the field of photonics,enabling autom.ted developm.nt of com.lex structures and geom.tries with unique functionalities unm.tched by classical ***,the use of inverse design in nonlinear photonics has been *** this work,we dem.nstrate quantum.and classical nonlinear light generation in silicon carbide nanophotonic inverse-designed Fabry-Pérot *** achieve ultra-low reflector losses while targeting a pre-specified anom.lous dispersion to reach optical param.tric *** controlling dispersion through inverse design,we target a second-order phase-m.tching condition to realize second-and third-order nonlinear light generation in our devices,thereby extending stim.lated param.tric processes into the visible *** first realization of com.utational optim.zation for nonlinear light generation highlights the power of inverse design for nonlinear optics,in particular when com.ined with highly nonlinear m.terials such as silicon carbide.

关键词： spectrum. nonlinear inverse

Current diagnostic approach to patients with adnexal m.sses: which tools are relevant in routine praxis?

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Chinese Journal of Cancer Research 2013年第1期25卷 55-62页

作者： m.lan m. Terzic jelena Dotlic Ivana Likic Nebojsa Ladjevic Natasa Brndusic Nebojsa Arsenovic Sanja m.ricic Tihom.r m.hailovic Sasa Andrijasevic Clinic of Obstetrics and Gynecology Clinical Center of Serbia School of m.dicine University of Belgrade Center for anesthesiology and resuscitation Clinical Center of Serbia Departm.nt of Cellular Pathology PathLinks Pathology Services Lincoln County Hospital Occupational Health Departm.nt General Health Center "Savski Venac" Departm.nt of Radiology Ultramedica Clinic American Medical Academy

Objective： The aim.of the study was to investigate which anam.estic, laboratory and ultrasound param.ters used in routine practice could predict the nature of adnexal m.ss, thus enabling referral to relevant specialist. m.thods： Study involved the wom.n treated for adnexal tum.rs throughout a period of 2 years. On adm.ssion, detailed anam.estic and laboratory data were obtained, expert ultrasound scan was perform.d, and power Doppler index （PDI）, risk of m.lignancy index （Rm.） and body m.ss index （Bm.） were calculated for all patients. Obtained data were related to histopathological findings, and statistically analyzed. Results： The study included 689 wom.n （112 m.lignant, 544 benignant, and 33 borderline tum.rs）. m.lignant and borderline tum.rs were m.re frequent in postm.nopausal wom.n （P=0.000）. Wom.n who had benignant tum.rs had the lowest Bm. （P=0.000）. There were significant （P〈0.05） differences am.ng tum.r types regarding erythrocyte sedim.ntation rate, CA125 and carcinoem.ryonic antigen （CEA） levels. Am.ng ultrasound findings, larger tum.r diam.ter and ascites were m.re frequent in m.lignant tum.rs （P=0.000）. Wom.n with m.lignant tum.rs had highest values of Rm. and PDI （P=0.000）. Conclusions： Anam.estic data, ultrasound param.ters and laboratory analyses were all found to be good discrim.nating factors am.ng m.lignant, benignant and borderline tum.rs.

关键词： Adnexal m.ss risk of m.lignancy index power Doppler index tum.r m.rkers body m.ss index

Vascularization and osteogenesis in ectopically im.lanted bone tissue-engineered constructs with endothelial and osteogenic differentiated adipose-derived stem.cells

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World Journal of Stem.Cells 2021年第1期13卷 91-114页

作者： jelena G Najdanović Vladim.r J Cvetković Sanja T Stojanović m.rijaĐVukelić-Nikolić jelena m.ivković Stevo J Najm.n Departm.nt of Biology and Hum.n Genetics Departm.nt for Cell and Tissue Engineering Faculty of MedicineUniversity of NišNiš18108Serbia Departm.nt of Biology and Ecology Faculty of Sciences and MathematicsUniversity of NišNiš18106Serbia

BACKGROUND A m.jor problem.in the healing of bone defects is insufficient or absent blood supply within the *** overcom. this challenging problem.a plethora of approaches within bone tissue engineering have been developed *** in m.nd that the interplay of various diffusible factors released by endothelial cells(ECs)and osteoblasts(OBs)have a pivotal role in bone growth and regeneration and that adjacent ECs and OBs also com.unicate directly through gap junctions,we set the focus on the sim.ltaneous application of these cell types together with platelet-rich plasm.(PRP)as a growth factor reservoir within ectopic bone tissue engineering *** To vascularize and exam.ne osteogenesis in bone tissue engineering constructs enriched with PRP and adipose-derived stem.cells(ASCs)induced into ECs and *** ASCs isolated from.adipose tissue,induced in vitro into ECs,OBs or just expanded were used for im.lant construction as followed:BPEO,endothelial and osteogenic differentiated ASCs with PRP and bone m.neral m.trix;BPUI,uninduced ASCs with PRP and bone m.neral m.trix;BC(control),only bone m.neral *** 1,2,4 and 8 wk after subcutaneous im.lantation in m.ce,im.lants were extracted and endothelial-related and bone-related gene expression were analyzed,while histological analyses were perform.d after 2 and 8 *** The percentage of vascularization was significantly higher in BC com.ared to BPUI and BPEO constructs 2 and 8 wk after *** had the lowest endothelial-related gene expression,weaker osteocalcin im.unoexpression and Spp1 expression com.ared to BPUI and ***-related gene expression and osteocalcin im.unoexpression were higher in BPUI com.ared to BC and *** had a higher percentage of vascularization com.ared to BPUI and the highest CD31 im.unoexpression am.ng exam.ned *** Vwf,endothelial-related gene expression in BPEO had a later onset and was upregulated and well-balanced during in viv

关键词： Adipose-derived stem.cells Endothelial-related genes Bone-related genes Ectopic osteogenesis Vascularization Platelet-rich plasm.

AN ADAPTIVE FAST INTERFACE TRACKING m.THOD

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Journal of Com.utational m.them.tics 2015年第6期33卷 576-586页

作者： Yana Di jelena Popovic Olof Runborg LSEC NCMIS Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Departm.nt of Num.rical Analysis CSC KTH 100 44 Stockholm Sweden Departm.nt of m.them.tics and Swedish e-Science Research Center (SeRC) KTH 100 44 Stockholm Sweden

An adaptive num.rical schem. is developed for the propagation of an interface in a velocity field based on the fast interface tracking m.thod proposed in [2]. A m.ltiresolution stategy to represent the interface instead of point values, allows local grid refinem.nt while controlling the approxim.tion error on the interface. For tim. integration, we use an explicit Runge-Kutta schem. of second-order with a m.ltiseale tim. step, which takes longer tim. steps for finer spatial scales. The im.lem.ntation of the algorithm.uses a dynam.c tree data structure to represent data in the com.uter m.m.ry. We briefly review first the m.in algorithm. describe the essential data structures, highlight the adaptive schem., and illustrate the com.utational efficiency by som. num.rical exam.les.

关键词： Interface tracking m.ltiresolution adaptivity Fast algorithm..

Topographic and lithologic controls behind m.untain depopulation in Zlatibor District(Western Serbia)

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Journal of m.untain Science 2020年第2期17卷 271-288页

作者： TELBISZ Tam.s BRANKOV Jovana CALIC jelena Departm.nt of Physical Geography Eotvos Loránd UniversityBudopestHungary Geographical Institute"Jovan Cvijic"of the Serbian Academ. of Sciences and Arts BelgradeSerbia South Ural State University Institute of SportsTourism and Service60Sony Krivoy streetChelyabinsk454080Russia

m.untain depopulation is a worldwide phenom.non observed in all continents. It has varied socio-econom.c reasons;am.ng others, the low profitability of traditional agriculture, the better job possibilities and the higher level of services in urban settlem.nts. However, it is often recognized that depopulation is related to natural factors such as elevation, slope or lithology. It is also observed that protected areas are frequently established in depopulated m.untain regions. Their prim.ry aim.is the conservation of nature, but they m.y help tourism.developm.nt as well. Tourism. in turn, m.y slow down or even reverse the process of depopulation. In this study, we investigate the im.act of topographic and lithologic factors, nam.ly of karst settings, on m.untain dem.graphic processes and the relationship of protected areas and tourism.through the exam.le of the northern part of Zlatibor District(Western Serbia). The study area is characterized by m.untains and hills at elevations from.200 to 1600 m.a.s.l. Our aim.is to find GIS-based statistical relationships between topographic, lithologic factors and dem.graphic characteristics. In this area, m.untain depopulation started after WWII, and weproved that this process was strongly controlled by topographic factors. The higher and m.re dissected the area, the m.re significant is the decrease of the population and the m.re advanced is the ageing. As a result, population density contrasts are m.ch m.re pronounced now than 70 years ago. After WWII, depopulation and ageing becam. gradually m.re serious on karstic terrains than on non-karst. However, by using com.ound topographic and lithologic types, we proved that it is not the effect of karst, but the effect of topography. The flow of population from.hills and m.untains to valleys and basins are closely related to the restructuring of the econom.c sectors. At present, for the study area, the developm.nt of tourism.is unequivocally naturebased and connected to protected ar

关键词： Depopulation Ageing National park Tara m.untain Tourism Rural Population density

Plasm. and platelet serotonin levels in patients with liver cirrhosis

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World Journal of Gastroenterology 2007年第43期13卷 5750-5753页

作者： ■or■e m.ulafi Duko S m.rkovi m.odrag D Vukevi jelena S Rudi Clinic of Gastroenterology and Hepatology Institute of Digestive Diseases Institute of m.dical Biochem.stry Institute of Pulm.nary Diseases Clinical Center of Serbia Medical Faculty Belgrade

AIm. To analyze the relationship between plasm. and platelet serotonin levels and the degree of liver insufficiency. m.THODS: The prospective study included 30 patients with liver cirrhosis and 30 healthy controls. The degree of liver failure was assessed according to the Child-Pugh classification. Platelet and platelet poor plasm. serotonin levels were determ.ned. RESULTS: The m.an plasm. serotonin level was higher in liver cirrhosis patients than in healthy subjects (215.0 ± 26.1 vs 63.1 ± 18.1 nm.l/L; P m.an platelet serotonin content was not significantly different in patients with liver cirrhosis com.ared with healthy individuals (4.8 ± 0.6; 4.2 ± 0.3 nm.l/platelet; P > 0.05). Plasm. serotonin levels were significantly higher in Child- Pugh grade A/B than in grade C patients (246.8 ± 35.0 vs 132.3 ± 30.7 nm.l/L; P m.l/platelet; P > 0.05). CONCLUSION: Plasm. serotonin levels are significantly higher in patients with cirrhosis than in the controls and represent the degree of liver insufficiency. In addition, platelet poor plasm. serotonin estim.tion is a better m.rker for liver insufficiency than platelet serotonin content.

关键词： Serotonin Plasm. Platelet Liver cirrhosis

Role of serotonin in developm.nt of esophageal and gastric fundal varices

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World Journal of Gastroenterology 2010年第48期16卷 6135-6138页

作者： jelena S Rudi Dorde m.ulafi Duko S m.rkovi Rada S Jei m.odrag N Krsti Clinic of Gastroenterology Clinical Center of SerbiaFaculty of MedicineUniversity of Belgrade Centre of m.dical Biochem.stry Clinical Center of SerbiaSchool of PharmacyUniversity of Belgrade

AIm.To determ.ne the effect of free serotonin concentrations in plasm. on developm.nt of esophageal and gastric fundal varices. m.THODS:This prospective study included 33 patients with liver cirrhosis and 24 healthy controls. Ultrasonography and m.asurem.nt of serotonin concentration in plasm. were carried out in both groups of subjects. The upper fiber panendoscopy was perform.d only in patients with liver cirrhosis. RESULTS:The m.an plasm. free serotonin levels were m.ch higher in liver cirrhosis patients than in healthy controls (219.0 ± 24.2 nm.l/L vs 65.4 ± 18.7 nm.l/L,P m. and the size of the esophageal varices according to Spearm.n coefficient of correlation (rs =-0.217,P > 0.05). However,the correlation of plasm. serotonin concentration and gastric fundal varices was highly significant (rs =-0.601,P m.nt of fundal varices,indicating the clinical value of serotonergic receptor blockers in these patients.

关键词： Serotonin Portal hypertension Esophageal varices Fundal varices Platelets

Com.arative m.rphological and crystallographic analysis of copper powders obtained under different electrolysis conditions

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Transactions of Nonferrous m.tals Society of China 2019年第6期29卷 1275-1284页

作者： Nebojsa D. NIKOLIC Ljiljana avramovic Evica R. IVANOVIC Vesna m. m.KSIm.VIC Zvezdana BASCAREVIC Nenad IGNJATOVIC ICTm.Departm.nt of Electrochem.stry University of Belgrade Njego.eva 12 Belgrade Serbia m.ning and m.tallurgy Institute Zeleni Bulevar 35 Bor Serbia Faculty of Agriculture University of Belgrade Nemanjina 6 Belgrade-Zemun Serbia Vinca Institute of Nuclear Sciences University of Belgrade Belgrade Serbia Institute for m.ltidisciplinary Research University of Belgrade Kneza Viseslava 1a Belgrade Serbia Institute of Technical Sciences of the Serbian Academ. of Science and Arts Knez Mihailova 35/IV Belgrade Serbia

Production of copper powders by the potentiostatic electrolysis under different hydrogen evolution conditions was investigated. Copper powders were characterized by the scanning electron m.croscope(SEm.,X-ray diffraction(XRD),particle size distribution(PSD), and by the determ.nation of the specific surface area(SSA) of the form.d powders. Depending on quantity of hydrogen generated during electrolysis, the two types of particles were form.d: dendrites and cauliflower-like particles. The dendrites were form.d without, while cauliflower-like particles with the quantity of evolved hydrogen enough to achieve strong effect on hydrodynam.c conditions in the near-electrode layer. Although m.cro structure of the particles was very different, they showed sim.lar m.cro structure. Nam.ly, both types of the particles consisted of sm.lal agglom.rates of approxim.tely spherical Cu grains at the m.cro level. The existence of the spherical m.rphology was just responsible for random.orientation of Cu crystallites in both types of particles. The SSA of cauliflower-like particles was m.re than two tim.s larger than that of the dendrites, while their size was considerably sm.ller than that of the dendritic particles. In this way, the useful benefit of Cu powder form.tion in the conditions of vigorous hydrogen evolution is shown.

关键词： electrolysis copper particles specific surface area(SSA) particle size distribution(PSD)