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Problems of Lifts in Symplectic Geometry

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Chinese Annals of Mathematics,Series B 2019年第3期40卷 321-330页

作者： Arif SALIMOV Manouchehr BEHBOUDI ASL sevil KAZIMOVA Department of Algebra and Geometry Baku State University Department of Mathematics Salmas Branch Islamic Azad University

Let(M,ω)be a symplectic *** this paper,the authors consider the notions of musical(bemolle and diesis)isomorphisms ω~b:T M→T~*M and ω~?:T~*M→TM between tangent and cotangent *** authors prove that the complete lifts of symplectic vector field to tangent and cotangent bundles is ω~*** consequence of analyze of connections between the complete lift ~cω_(T M )of symplectic 2-form ω to tangent bundle and the natural symplectic 2-form dp on cotangent bundle,the authors proved that dp is a pullback o f^cω_(TM)by ω~?.Also,the authors investigate the complete lift ~cφ_T~*_M )of almost complex structure φ to cotangent bundle and prove that it is a transform by ω~?of complete lift^cφ_(T M )to tangent bundle if the triple(M,ω,φ)is an almost holomorphic *** transform of complete lifts of vector-valued 2-form is also studied.

关键词： Symplectic manifold Tangent bundle Cotangent bundle Transform of tensor fields Pullback Pure tensor Holomorphic manifold

Comparison of phenolic components and biological activities of two Centaurea *** by three extraction techniques

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 669-676页

作者： sevil Albayrak Bayram Atasagun Ahmet Aksoy Erciyes University Science FacultyDepartment of Biology38039 KayseriTurkey Akdeniz University Science FacultyDepartment of Biology07058 AntalyaTurkey

Objective: The present study aimed to compare the polyphenol content, total phenolic, total flavonoid, antioxidant and antimicrobial activity of the extracts obtained from Centaurea amaena Boiss. & Balansa and Centaurea aksoyi Hamzao?lu & Budak. Methods: Both species were subjected to maceration, Soxhlet and ultrasonication extractions with methanol in order to macerated(ME), Soxhlet(SE) and ultrasonicated(UE) extracts. Their phenolic profiles were qualitatively examined by LC-MS. Their antioxidant activities were determined by phosphomolybdenum, β-carotene bleaching and DPPH assays. Agar diffusion and broth dilution methods were carried out to find the antimicrobial activity of these extracts against fifteen microorganisms. Results: Quercetin, quercetin-3-β-D-glucoside and protocatechuic acid were the main components of the both extracts obtained by Soxhlet extraction. The highest phenolic and flavonoid contents were found in the UE for both species. All the extracts exhibited good total antioxidant and DPPH radical scavenging activity. UE obtained from C. amaena showed the highest antioxidant activity with the highest phenolic and flavonoid contents. The antibacterial activity of UE obtained from C. amaena was better than other extracts and antibacterial activity of C. amaena was also better than C. aksoyi. Discussion: This study confirms that ultrasonic extraction may be an ideal, simple and rapid method to obtain polyphenol-rich extracts have antioxidant as well as antibacterial activity from both Centaureaspecies especially from C. amaena.

关键词： Centaurea aksoyi Centaurea amaena LC-MS Antioxidant activity Antimicrobial activity

Corresponding author:Yixing Duan,E-mail address:duanyixing666@***

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Frontiers of Architectural Research 2024年第6期13卷 1308-1326页

作者： sevil Yazici Department of Architecture Istanbul Technical UniversityIstanbul 34367Turkey

Various parameters can be integrated in material-based computational design in *** are the main driver of these processes and evaluated with the constraints related to the form,performance,and fabrication ***,current methodologies mostly involve investigating already existing *** on computational material design,in which new materials are developed by designing their microstructures in response to the performative issues,are generally undertaken at the material scale,and not adopted to the architectural design process *** resolve this issue,the methodology titled Interscalable Material Microstructure Organization in Performance-based Computational Design(I2MO_PCD)is developed and presented in three stages,including(1)identification of different types of material microstructures,(2)computational material design,and(3)***-based material modelling and visualization,and algorithmic modelling techniques are utilized,followed by various performance simulations as a part of an iterative *** microstructure organizations are designed computationally,organized under three main groups as linear-curvilinear,crystal and *** outcomes of different performance analyses,including structure,radiation,direct sun hours,acoustics and thermal bridge were ***,the role of geometrical organization of microstructures,scales and material types in different performance computations were identified,by designing and fabricating synthetic materials.

关键词： Material microstructure Computational design Performance computation Architectural design

Chemical Effect Analyses of 3d Elements by Study of X-Ray Fluorescence Spectra

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光谱学与光谱分析 2018年第8期38卷 2630-2637页

作者： sevil(Porikli) DURDAGI Faculty of Arts and Sciences Department of Physics Erzincan University Erzincan 24030 Turkey

Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed using a ZSX-100 esequential spectrometer equipped with an RhX-ray tube *** accurate analytical representation of each line was obtained by a fit to a Lorentz *** spectra were analyzed in order to examine the KX-ray peak parameters such as asymmetry index,peak energy and relative intensity *** energy shifts and relative intensities weredetermined tobetter understand the chemical effect.

关键词： Asymmetry index Relative intensity ratio Chemical effect Wavelength dispersive X-ray spectroscopy(WDXRF)

Biological activities of Wiedemannia multifida(Linnaeus) Bentham and Wiedemannnia orientalis Fisch.& Mey.

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Asian Pacific Journal of Tropical Biomedicine 2013年第3期3卷 196-201页

作者： sevil Albayrak Ahmet Aksoy Department of Biology Science FacultyErciyes University

Objective:To evaluate total phenolic,antioxidant and antimicrobial activities of methanolic extracts of the Wiedemannia multifida(***)and Wiedemannnia orientalis(***).Methods:Phosmomolybdenum assay,DPPH radical scavenging activity andβ-carotent-linoleate bleaching were used to evaluate the antioxidant ***:The total phenolics were found to be(22.45±0.60)and(9.53±0.00)mg gallic acid equivalents(GAE)/g in *** and *** extracts,*** predominant phenolic compounds identified by HPLC-DAD in the both extracts were rutin+ellagic acid and *** antioxidant capacity and DPPH radical scavenging activity of *** were higher than ***β-carotene-linoleic acid system,both extracts exhibited strong inhibition against linoleic acid *** activity was assessed by the agar diffusion method against fifteen *** extracts exhibited remarkable antibacterial ***:The present study suggests that methanolic extracts of *** and *** could be a good source of antioxidant and antimicrobial agents in foods,pharmaceuticals preparations.

关键词： Wiedemannia Antimicrobial activity Antioxidant activity Phenolic

Bayesian analysis of time‑varying interactions between stock returns and foreign equity flows

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Financial Innovation 2021年第1期7卷 1075-1099页

作者： Boubekeur Baba Güven sevil Graduate School of Social Sciences Anadolu UniversityEskişehirTepebaşı26470Turkey Open Education Faculty Anadolu UniversityEskişehirTepebaşı26470Turkey

This study discusses the trading behavior of foreign investors with respect to economic uncertainty in the South Korean stock market from a time-varying *** employ a news-based measure of economic uncertainty along with the model of time-varying parameter vector autoregression with stochastic *** empirical analysis reveals several new findings about foreign investors’trading ***,we find evidence that positive feedback trading often appears during periods of high economic uncertainty,whereas negative feedback trading is exclusively observable during periods of low economic ***,the foreign investors’feedback trading appears mostly to be well-timed and often leads the time-varying economic uncertainty except in periods of global ***,lagged negative(positive)response of net flows to economic uncertainty is found to be coupled with lagged positive(negative)feedback ***,the study documents an asymmetric response of foreign investors with regard to negative and positive shocks of economic ***,we find that they instantly turn to positive feedback trading after a negative contemporaneous response of net flows to shocks of economic *** contrast,they move slowly toward negative feedback trading after a positive response of net flows to uncertainty shocks.

关键词： Stock returns Net foreign equity flows Time-varying parameter VAR Feedback trading Forecast ability Economic policy uncertainty

Neuroprotective effect of systemic and/or intravitreal rosuvastatin administration in rat glaucoma model

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 340-347页

作者： Metin Unlu Zeynep Aktas Pinar Uyar Gocun sevil Ozger Ilhan Murat Hasanreisoglu Berati Hasanreisoglu Department of Ophthalmology Erciyes University Schoolof Medicine Kayseri 38039 Turkey Department of Ophthalmology Gazi University School of Medicine Besevler Ankara 06560 Turkey Department of Pathology Gazi University School of Medicine Besevler Ankara 06560 Turkey Department of Pharmacology Gazi University School of Medicine Besevler Ankara 06560 Turkey

AIM： To evaluate the neuroprotective effect of rosuvastatin, in a rat experimental glaucoma model. METHODS： Ocular hypertension was induced in right eyes of Long-Evans rats （n=30） by cauterization of three episcleral veins. Left eyes were defined as controls. Rats were divided into five groups： oral rosuvastatin, intravitreal rosuvastatin, oral ＋intravitreal rosuvastatin, intravitreal sham and glaucoma without intervention. Rats were sacrificed at day 14. Retinal ganglion cell （RGC） number was assessed by histopathological analysis. Terminal deoxynucleotidyl transferase-mediated dUTP-nick end-labeling （TUNEL） staining and the expression of glial fibrillary acidic protein （GFAP） in RGC layer was also examined. RESULTS： A significant intraocular pressure （lOP） elevation was seen （P=0.002）. Elevated lOP resulted in a significant decrease in number of RGCs in group 5 （70.33 ±8.2 cells/mm2） when compared with controls （92.50 ±13.72 cells/mm2; P=0.03）. The RGC number in group 1 （92.4±7.3 cells/mm2） was significantly higher than group 5 （ρ=0.03）. The numbers of RGC in groups 2, 3 （57.3±8.2 cells/mm2, 60.5±12.9 cells/mm2） were comparable with that of group 5 （ρ=0.18 and P=0.31）. The apoptosis rates with TUNEL staining were also parallel to RGC number. Animals with experimentally induced glaucoma showed an increase in retinal GFAP immunoreacUvity. CONCLUSION： Decrease in RGC loss and apoptosis suggest the neuroprotective potential of oral rosuvastatin treatment in a rat model of ocular hypertension. Howeverintravitreal rosuvastatin showed a contrary effect and further studies are required.

关键词： KEYWORDS: rat glaucoma model retinal ganglion cellnumber rosuvastatin neuroprotection

Interaction between seed size and NaCl on germination and early seedling growth of some Turkish cultivars of chickpea(Cicer arietinum L.)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第5期9卷 371-377页

作者： Muharrem KAYA Gamze KAYA Mehmet Demir KAYA Mehmet ATAK sevil SAGLAM Khalid Mahmood KHAWAR Cemalettin Yasar CIFTCI Department of Field Crops Faculty of AgricultureSuleyman Demirel University Central Research Institute for Field Crops Ministry of Agriculture and Rural Affairs Department of Field Crops Faculty of AgricultureMustafa Kemal University Department of Field Crops Faculty of AgricultureUniversity of Ankara

Chickpea is an important food legume crop of Turkey and is largely grown for human consumption on low moisture or salt-affected soils. The objective of the study was to find the effects of NaCl stress at electrical conductivities of 4.5, 8.6, 12.7 and 16.3 dS/m and seed sizes （7, 8 and 9 mm） on germination and early seedling growth of three popular chickpea cultivars （AKN-97, Gokce and Uzunlu-99）. Mean frequency of germination, germination time, germination index, root length, shoot length and seedling fresh weight showed seed size-dependent responses ofcultivars to salt stress. In general, small seeds germinated and grew more rapidly compared to medium and large seeds of the same cultivars against all levels of salt stress, with the best results in cultivar Uzunlu-99. No effect of NaCl treatments was observed on frequency of germination; however, a drastic decrease in early seedling growth was recorded at increased NaC1 concentrations. Regression analysis results showed a significantly positive relationship （P〈0.01） between seed size and mean germination time, whereas a significantly negative relationship was recorded between seed size and germination index, root length, shoot length. Moreover, linear regression values apparently confirmed that increased seed size in each cultivar affected decreased germination index, root and shoot lengths with enhanced mean germination time. Thus, it was concluded that the use of small seeds could considerably reduce the production costs of chickpea in salt-affected soils.

关键词： Chickpea (Cicer arietinum L.) NaCl stress Cultivar Seed size Germination

Role of magnesium and aluminum substitution on the structural properties and bioactivity of bioglasses synthesized from biogenic silica

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Bioactive Materials 2020年第1期5卷 66-73页

作者： Burcu Karakuzu-Ikizler Pınar Terzioğlu Yeliz Basaran-Elalmis Bilge Sema Tekerek sevil Yücel Department of Bioengineering Faculty of Chemistry and MetallurgyYildiz Technical UniversityIstanbulTurkey Department of Fiber and Polymer Engineering Faculty of Engineering and Natural SciencesBursa Technical UniversityBursaTurkey Department of Genetics and Bioengineering Faculty of Engineering and ArchitectureNişantaşıUniversityIstanbulTurkey

The objective of this study was to investigate the effect of magnesium(1 wt%)and aluminum(1 wt%)incorporation on the in vitro bioactivity and biodegradation behavior of 45S5 bioactive glasses synthesized from rice husk biogenic *** performance of biogenic silica-based samples was compared well with commercial silica-based *** in vitro biodegradation behavior of bioactive glasses was evaluated by the weight loss of samples and pH variation in the Tris buffer *** on composition,bioglasses possessed different properties before and after simulated body fluid(SBF)*** incorporation of magnesium(Mg)and aluminum(Al)enhanced the Vickers hardness of *** the bioglasses showed the hydroxyapatite layer formation after SBF treatment as confirmed by the dissolution,FTIR,SEM and XRD analysis,however it was more prominent in the rice husk silica-based 45S5 *** biogenic silica seems to be a promising starting material for bioglass systems to be used in bone tissue engineering applications.

关键词： Bioactivity Biodegradation Biomaterial Rice husk silica SBF