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Article Citation - WoS: 24Citation - Scopus: 27The Pimpled Gold Nanosphere: a Superior Candidate for Plasmonic Photothermal Therapy(Dove Medical Press Ltd, 2020) Nasseri, Behzad; Turk, Mustafa; Kosemehmetoglu, Kemal; Kaya, Murat; Piskin, Erhan; Rabiee, Navid; Webster, Thomas J.Background: The development of highly efficient nanoparticles to convert light to heat for anti-cancer applications is quite a challenging field of research. Methods: In this study, we synthesized unique pimpled gold nanospheres (PGNSs) for plasmonic photothermal therapy (PPTT). The light-to-heat conversion capability of PGNSs and PPTT damage at the cellular level were investigated using a tissue phantom model. The ability of PGNSs to induce robust cellular damage was studied during cytotoxicity tests on colorectal adenocarcinoma (DLD-1) and fibroblast cell lines. Further, a numerical model of plasmonic (COMSOL Multiphysics) properties was used with the PPTT experimental assays. Results: A low cytotoxic effect of thiolated polyethylene glycol (SH-PEG400-SH-) was observed which improved the biocompatibility of PGNSs to maintain 89.4% cell viability during cytometry assays (in terms of fibroblast cells for 24 hrs at a concentration of 300 mu g/mL). The heat generated from the nanoparticle-mediated phantom models resulted in Delta T=30 degrees C, Delta T=23.1 degrees C and Delta T=21 degrees C for the PGNSs, AuNRs, and AuNPs, respectively (at a 300 mu g/mL concentration and for 325 sec). For the in vitro assays of PPTT on cancer cells, the PGNS group induced a 68.78% lethality (apoptosis) on DLD-1 cells. Fluorescence microscopy results showed the destruction of cell membranes and nuclei for the PPTT group. Experiments further revealed a penetration depth of sufficient PPTT damage in a physical tumor model after hematoxylin and eosin (H&E) staining through pathological studies (at depths of 2, 3 and 4 cm). Severe structural damages were observed in the tissue model through an 808-nm laser exposed to the PGNSs. Conclusion: Collectively, such results show much promise for the use of the present PGNSs and photothermal therapy for numerous anti-cancer applications.Article Citation - WoS: 58Fast Neutron Imaging With Semiconductor Nanocrystal Scintillators(Amer Chemical Soc, 2020) McCall, Kyle M.; Sakhatskyi, Kostiantyn; Lehmann, Eberhard; Walfort, Bernhard; Losko, Adrian S.; Montanarella, Federico; Kovalenko, Maksym, VFast neutrons offer high penetration capabilities for both light and dense materials due to their comparatively low interaction cross sections, making them ideal for the imaging of large-scale objects such as large fossils or as-built plane turbines, for which X-rays or thermal neutrons do not provide sufficient penetration. However, inefficient fast neutron detection limits widespread application of this technique. Traditional phosphors such as ZnS:Cu embedded in plastics are utilized as scintillators in recoil proton detectors for fast neutron imaging. However, these scintillation plates exhibit significant light scattering due to the plastic-phosphor interface along with long-lived afterglow (on the order of minutes), and therefore alternative solutions are needed to increase the availability of this technique. Here, we utilize colloidal nanocrystals (NCs) in hydrogen-dense solvents for fast neutron imaging through the detection of recoil protons generated by neutron scattering, demonstrating the efficacy of nanomaterials as scintillators in this detection scheme. The light yield, spatial resolution, and neutron-vs-gamma sensitivity of several chalcogenide (CdSe and CuInS2)-based and perovskite halide-based NCs are determined, with only a short-lived afterglow (below the order of seconds) observed for all of these NCs. FAPbBr(3) NCs exhibit the brightest total light output at 19.3% of the commercial ZnS:Cu(PP) standard, while CsPbBrCl2:Mn NCs offer the best spatial resolution at similar to 2.6 mm. Colloidal NCs showed significantly lower gamma sensitivity than ZnS:Cu; for example, 79% of the FAPbBr(3) light yield results from neutron-induced radioluminescence and hence the neutron-specific light yield of FAPbBr(3) is 30.4% of that of ZnS:Cu(PP). Concentration and thickness-dependent measurements highlight the importance of increasing concentrations and reducing self-absorption, yielding design principles to optimize and foster an era of NC-based scintillators for fast neutron imaging.Article Citation - WoS: 39Citation - Scopus: 44A Novel Treatment Strategy for Preterm Birth: Intra-Vaginal Progesterone-Loaded Fibrous Patches(Elsevier, 2020) Cam, Muhammet Emin; Hazar-Yavuz, Ayse Nur; Cesur, Sumeyye; Ozkan, Ozan; Alenezi, Hussain; Sasmazel, Hilal Turkoglu; Edirisinghe, MohanProgesterone-loaded poly(lactic) acid fibrous polymeric patches were produced using electrospinning and pressurized gyration for infra-vaginal application to prevent preterm birth. The patches were intravaginally inserted into rats in the final week of their pregnancy, equivalent to the third trimester of human pregnancy. Maintenance tocolysis with progesterone-loaded patches was elucidated by recording the contractile response of uterine smooth muscle to noradrenaline in pregnant rats. Both progesterone-loaded patches indicated similar results from release and thermal studies, however, patches obtained by electrospinning had smaller average diameters and more uniform dispersion compared to pressurized gyration. Patches obtained by pressurized gyration had better results in production yield and tensile strength than electrospinning; thereby pressurized gyration is better suited for scaled-up production. The patches did not affect cell attachment, viability, and proliferation on Vero cells negatively. Consequently, progesterone-loaded patches are a novel and successful treatment strategy for preventing preterm birth.Article Citation - WoS: 11Citation - Scopus: 20The Taylor Series Method and Trapezoidal Rule on Time Scales(Elsevier Science inc, 2020) Georgiev, Svetlin G.; Erhan, Inci M.The Taylor series method for initial value problems associated with dynamic equations of first order on time scales with delta differentiable graininess function is introduced. The trapezoidal rule for the same types of problems is derived and applied to specific examples. Numerical results are presented and discussed. (c) 2020 Elsevier Inc. All rights reserved.Article Queer Lives in the Social Media Prism: Precarious LGBTQIA Plus Visibility and Lateral Surveillance in Azerbaijan(Sage Publications Inc, 2025) Seyidov, Ilgar; Pentzold, ChristianIn countries where state institutions and the public largely reject LGBTQIA+ identities and issues, queer people struggle with visibility. Next to governments and technology providers, what queer people do, who they connect to, and how they express themselves is being watched and scrutinized by their families and proximate relations. This lateral surveillance is afforded by social media that establish, as we argue in this article, a prism. Here, LGBTQIA+ lives become refracted as extensive though incoherent patterns of digital traces. How queer people respond to this situation where the binary of visible versus invisible falls apart is poorly understood. To address that gap, we interrogate the precarious management of visibility attempted by LGBTQIA+ people in Azerbaijan with its heteropatriarchal, honor-driven culture. Based on our exploratory interview study, we find that queer Azerbaijanis were confronted with a highly ambivalent scopic setup where context collision loomed large. In effect, they supported LGBTQIA+ visibility but had personally decided not to live or promote it. Yet whilst their attempts to remain opaque may contradict their activistic compliancy, this was a logical reaction to too hard to handle terms of visibility.Article Citation - WoS: 27Citation - Scopus: 28Generalized Meir-Keeler Type Contractions on g-metric Spaces(Elsevier Science inc, 2013) Mustafa, Zead; Aydi, Hassen; Karapinar, ErdalIn this manuscript, we introduce generalized Meir-Keeler type contractions over G-metric spaces. Moreover, we show that every orbitally continuous generalized Meir-Keeler type contraction has a unique fixed point on complete G-metric spaces. We illustrate our results by some given examples. (C) 2013 Elsevier Inc. All rights reserved.Article Citation - WoS: 33Citation - Scopus: 37Discrete Sizing Optimization of Steel Trusses Under Multiple Displacement Constraints and Load Cases Using Guided Stochastic Search Technique(Springer, 2015) Azad, S. Kazemzadeh; Hasancebi, O.The guided stochastic search (GSS) is a computationally efficient design optimization technique, which is originally developed for discrete sizing optimization problems of steel trusses with a single displacement constraint under a single load case. The present study aims to investigate the GSS in a more general class of truss sizing optimization problems subject to multiple displacement constraints and load cases. To this end, enhancements of the GSS are proposed in the form of two alternative approaches that enable the technique to deal with multiple displacement/load cases. The first approach implements a methodology in which the most critical displacement direction is considered only when guiding the search process. The second approach, however, takes into account the cumulative effect of all the critical displacement directions in the course of optimization. Advantage of the integrated force method of structural analysis is also utilized for further reduction of the computational effort in these approaches. The proposed enhancements of GSS are investigated and compared with some selected techniques of design optimization through six truss structures that are sized for minimum weight. The numerical results reveal that both enhancements generally provide promising solutions with an insignificant computational effort.Article Citation - WoS: 31Citation - Scopus: 30Structure of the Ξb< Resonance(Amer Physical Soc, 2018) Aliev, T. M.; Azizi, K.; Sarac, Y.; Sundu, H.We explore the recently observed Xi(b)(6227)(-) resonance to fix its quantum numbers. To this end, we consider various possible scenarios: It can be considered as either a 1P or 2S excitation of the Xi(b) and Xi'(b)(5935) ground-state baryons with spin-1/2 or the 1P or 2S excitation of the ground-state Xi(b)(5955) with spin-3/2. We calculate the masses of the possible angular-orbital 1P and 2S excited states corresponding to each channel employing the QCD sum rule technique. It is seen that all the obtained masses are in agreement with the experimentally observed value, implying that the mass calculations are not enough to determine the quantum numbers of the state under question. Therefore, we extend the analysis to investigate the possible decays of the excited states into Lambda K-b(0)- and Xi(-)(b) pi. Using the light cone QCD sum rule method, we calculate the corresponding strong coupling constants, which are used to extract the decay widths of the modes under consideration. Our results on decay widths indicate that the Xi(b)(6227)(-) is a 1P angular-orbital excited state of the Xi(b)(5955) baryon with quantum numbers J(P) = 3/2(-).Article Citation - WoS: 6Citation - Scopus: 10Male and Female Differences in the Use of Social Media for Learning Purposes(Routledge Journals, Taylor & Francis Ltd, 2018) Akman, Ibrahim; Turhan, CigdemThis study aims to explore the differences between male and female users' behaviour with regard to acceptance of social media for learning in higher educational institutions. For this purpose, a survey was conducted and the least square regression analysis approach was utilised to investigate the relationships among the constructs in the research model for male and female users from a general and ethical perspective, focusing on the reliability, performance and awareness factors. The findings from the analysis reveal that a significant degree of diversity is present in the factors represented by general reliability', ethical reliability', ethical performance', ethical awareness' and ethical intention'.Article Citation - WoS: 45Citation - Scopus: 49Recrystallization and Grain Growth Kinetics of In718 Manufactured by Laser Powder Bed Fusion(Elsevier, 2022) Dogu, Merve Nur; Davut, Kemal; Obeidi, Muhannad Ahmed; Yalcin, Mustafa Alp; Gu, Hengfeng; Low, Thaddeus Song En; Brabazon, DermotThe recrystallization and grain growth behaviour of IN718 alloy additively manufactured by laser powder bed fusion (L-PBF) is presented herein. The effects of three different temperatures (1050, 1150 and 1250 degrees C) and holding times (15, 45 and 90 min) were investigated. The texture evolution of the samples was recorded via electron backscatter diffraction (EBSD). The as-built sample is composed of bowl-shaped melt pools, a chessboard-like grain pattern and has a cube texture {100}<001>. Recrystallized grains were observed in the samples treated at 1150 degrees C for 15 min, as well as the samples treated for longer periods and at higher temperatures. Recrystallization was observed to start from high dislocation density regions, including the overlapping melt pools and the borders of the chessboard-like pattern. The initial cube texture transforms into a first-generation cube-twin texture {122}<212> via a twinning-assisted recrystallization mechanism. Then, those recrystallization nuclei sweep through the high defect density matrix; during which almost no new twins are formed. The samples treated at 1250 degrees C are almost completely recrystallized, which forms a weaker cube texture and a stronger P-orientation {011}<112>. However, the growth of recrystallized grains is very limited due to the presence of non-coherent precipitates. (C) 2022 The Author(s). Published by Elsevier B.V.
