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Article Citation - WoS: 5Citation - Scopus: 5Structural and Electrical Characterizations of the as Grown and Annealed Au/Mοo3< Bandpass Filters(Wiley, 2019) Khanfar, Hazem K.; Qasrawi, Atef; Daraghmeh, Masa; Abusaa, MuayadIn this work, the structural, morphology, and electrical properties of two 500 nm thick molybdenum trioxide layers that are sandwiched with indium slab of thickness of 200 nm (MoO3/In/MoO3 [MIM]) to form a bandpass filter are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and impedance spectroscopy techniques, respectively. The MIM films which coated onto Au thin film substrates by the thermal evaporation technique under vacuum pressure of 10(-5) mbar was post annealed at 250 degrees C in air atmosphere. While the XRD analysis revealed polycrystalline hexagonal lattice structure of the Au/MLM samples, the SEM and EDS analysis displayed grains of sizes of 350 nm and stoichiometric structure of MoO3. Electrically, indium layer which caused n-type conduction with donor level of 299 meV, forced the material to exhibit negative capacitance (NC) effect at high frequencies (above 1.1 GHz). The impedance spectroscopy which was recorded in the frequency domain of 0.01 to 1.80 GHz, also revealed low pass and high pass filters characteristics in the low and high frequency domains, respectively. The annealing of the Au/MIM samples, decreased the crystallite and grain sizes and increased the microstrain, the defect density and the stacking faults. Small amount of excess oxygen and some indium deficiency are observed upon annealing. In addition, the annealing shifted the donor level closer to the bottom of the conduction band and inverted the NC effect from high to low frequency regions. The study indicates the applicability of the Au/MIM/C structures as microwave cavities and parasitic capacitance cancellers in electronic circuits.Article Does Dexmedetomidine Induce Bone Regeneration in Cranial Defects in Rabbits(Taylor & Francis Ltd, 2025) Erkan, Gozde Nur; Tekin, Umut; Boyacioglu, Ozge; Korkusuz, Petek; Orhan, Kaan; Kirman, Betul; Onder, Mustafa ErcumentDexmedetomidine has been shown to exert protective and curative effects on various tissues and organs in different pathological processes. This study aimed to investigate the effect of dexmedetomidine on the regeneration process after making holes in the parietal bones of rabbits. Twenty-four male Oryctolagus cuniculus rabbits were allocated to three groups, and an 8-mm circular parietal critical-sized bone defect was induced in each animal. Group_C (control) received saline; Group_LD (low dose) was given dexmedetomidine 2.75 mu g/kg; Group_HD (high dose), dexmedetomidine 5.5 mu g/kg; all were administered intraperitoneally for 7 days. After 8 weeks the bones were examined by micro-computed tomography (micro-CT) and histomorphometry. The results indicated that regeneration was improved in both the dexmedetomidine-treated groups. The lower dose increased the bone volume ratio (BV/TV) more than the higher dose. Trabecular thickness, connectivity value, and connectivity density were also higher in Group_LD than in Group_HD. Significant intramembranous ossification was observed in the dexmedetomidine-treated groups, and active osteoblasts were seen at the margins of new bone trabeculae. We conclude that dexmedetomidine, especially at the lower dosage, increases osteoblastic activity and regeneration quality.Article Citation - WoS: 10Citation - Scopus: 10The Role of Environmental Factors in the Investment Prioritization of Facilities Using Recycled Pvc(Hard, 2021) Bac, UgurThere are many types of solid wastes however, plastic wastes are among the ones which have several harmful effects on the environment. Plastic wastes have a long decomposition time in nature and the dangerous chemical compounds in them make them a threat for the environment along with other types of waste. Contamination caused by the plastic wastes attracts worldwide attention nowadays. As a member of thermoplastic polymers family, polyvinyl chloride (PVC) products are one of the most preferred type of plastic composition, which holds an important ratio in the total plastic waste amount. PVC wastes should either be disposed or recycled to minimize their harmful effects on the environment. The disposal approach is easy and cheap, but recycling alternative requires the investment on special facilities hence, a more expensive solution. However, disposal alternatives, such as landfilling and incineration, may also cause pollution due to high chlorine content of PVC; whereas, mechanical and chemical recycling options reduce many environmental problems. There is a clear tradeoff in the decision of handling PVC waste between the costs and environmental effects. The purpose of this study is to evaluate the factors considered during the investment decisions of PVC manufacturers to find out the importance of environmental factors by using a multi-criteria group decision making method.Article Citation - WoS: 4Citation - Scopus: 4Incidence and Predictors of Permanent Pacemaker Implantation After Transcatheter Aortic Valve Implantation With a Balloon-Expandable Biosprosthesis in Patients With Bicuspid Aortic Valves(Termedia Publishing House Ltd, 2024) Suygun, Hakan; Kasapkara, Haci Ahmet; Guney, Murat Can; Polat, Melike; Bozkurt, EnginIntroduction:
There are few data on permanent pacemaker implantation (PPMI) in patients who have undergone transcatheter aortic valve implantation (TAVI) for bicuspid aortic valve (BAV) stenosis.
Aim:
The purpose of this study was to evaluate the predictors and incidence of PPMI in bicuspid patients using a balloon-expandable (BE) TAVI device.
Material and methods:
A total of 62 patients with bicuspid morphology who had undergone successful TAVI using a BE device without previous PPMI were included (retrospectively). Their baseline clinical, electrocardiographic (ECG), echocardiographic, and multislice computed tomography (MSCT) details were collected.
Results:
The incidence of PPMI after TAVI in this BAV cohort was 12.9%. All eight patients with PPMs were found to have type 1 left-right (LR) fusion morphology. In univariate analysis, the presence of right bundle branch block (RBBB) in preprocedural ECG ( p < 0.0001), short membraneous septum (MS) evaluated in MSCT ( p < 0.0001), and increased annulus-left main coronary artery distance ( p = 0.02) were statistically significant for PPMI. Among these parameters included in the model using multivariate Firth logistic regression analysis, the presence of preprocedural RBBB ( p = 0.001) and shortness of the MS in MSCT ( p = 0.004) were independent risk factors for predicting postprocedural PPMI in patients who underwent TAVI among those with BAV.
Conclusions:
Preprocedural RBBB on ECG and shorter MS are independent risk factors for PPMI after TAVI in BAV patients and these parameters should be considered before the procedure to guide clinical decision making. Type 1 LR patients may be considered at increased risk of PPMI.Conference Object Citation - Scopus: 64Performance Analysis of Ad-Hoc Networks Under Black Hole Attacks(Institute of Electrical and Electronics Engineers Inc., 2007) Dokurer,S.; Erten,Y.M.; Acar,C.E.A wireless ad-hoc network is a temporary network set up by wireless nodes usually moving randomly and communicating without a network infrastructure. Due to security vulnerabilities of the routing protocols, however, wireless ad-hoc networks may be unprotected against attacks by the malicious nodes. In this study we investigated the effects of Black Hole attacks on the network performance. We simulated black hole attacks in Network Simulator 2 (ns-2) and measured the packet loss in the network with and without a black hole. We also proposed a simple solution against black hole attacks. Our solution improved the network performance in the presence of a black hole by about 19%. © 2007 IEEE.Article Citation - WoS: 18Citation - Scopus: 19A Generalization of Ciric Quasicontractions(Hindawi Publishing Corporation, 2012) Karapinar, Erdal; Kieu Phuong Chi; Tran Duc ThanhWe proved a fixed point theorem for a class of maps that satisfy Ciric's contractive condition dependent on another function. We presented an example to show that our result is a real generalization.Article Citation - WoS: 2Citation - Scopus: 3Physical and Biological Characteristics of Electrospun Poly (vinyl Alcohol) and Reduced Graphene Oxide Nanofibrous Structure(Taylor & Francis Ltd, 2024) Sasmazel, Hilal Turkoglu; Alazzawi, Marwa; Gozutok, Melike; Sadhu, VeeraThe fabrication of graphene-based nanocomposites has been a topic of increasing interest due to graphene's exceptional physical properties and the ability to enhance the properties of various polymeric materials. Evaluating the biocompatibility of these nanocomposites is crucial to ensure their safe and effective use in biomedical applications. This study characterized and assessed the biocompatibility of previously fabricated electrospun polyvinyl alcohol (PVA)/reduced graphene oxide rGO fibrous structures by conducting a comprehensive assessment of their physical and biological characteristics. Contact angle measurements revealed that adding rGO to electrospun PVA fibers enhanced the surface wettability, improving the fibrous structure's PBS absorption capacity and degradation behavior. Including the rGO content resulted in a higher water vapor transmission rate, reaching similar to 48 g/m2day for PVA + 0.5 wt.% rGO and similar to 45 g/m2day for PVA + 1.0 wt.% rGO, compared to similar to 40 g/m2day for electrospun PVA fibers. Cell culture studies, including MTT assay, alkaline phosphatase (ALP) activity analysis, alizarin red staining, fluorescence microscopy, and SEM analyses, demonstrated that electrospun PVA + 1.0 wt.% rGO nanocomposites exhibited superior cell viability, proliferation, and growth compared to other samples, due to the improved physical properties of the PVA + 1.0 wt.% rGO fibrous structure.Article Citation - WoS: 10Citation - Scopus: 9The Randomized Controlled Study of Low-Level Laser Therapy, Kinesio-Taping and Manual Lymphatic Drainage in Patients With Stage Ii Breast Cancer-Related Lymphedema(Galenos Publ House, 2023) Yılmaz, Sedef Selçuk; Ayhan, Fikriye FigenObjective: To compare the effects of low-level laser therapy, kinesio-taping and manual lymphatic drainage (MLD) on the affected arm volume, quality of life, arm function, neuropathic pain and shoulder mobility in patients with stage II breast cancer-related lymphedema. Materials and Methods: Forty-five breast cancer patients with stage II lymphedema were included. The patients were randomized to three groups and treated with MLD, kinesio-taping or low-level laser therapy. After these different therapeutic modalities, all patients received multilayer compression bandaging, lymphedema remedial exercises, skin care, and a patient education program by the same lymphedema therapist. All treatments were applied 5-days a week for three weeks. The lymphedema compression garments were prescribed to all patients and follow-up visits were planned at the end of the treatment, and at four and 12 weeks. The efficacy of the treatments was evaluated by volumetric calculations based on circumferential measurements using the formula for a truncated cone, in addition to goniometric assessments for shoulder joint ROM, and questionnaires: Quick-disability of arm, shoulder and hand for arm disability; pain-detect for neuropathic pain; and quality of life for arm lymphedema (LYMQOL-arm). Results: The baseline patient and disease characteristics, and outcome measures were similar between groups. All treatment modalities were found to be effective in decreasing arm volume, and improving quality of life, upper extremity disability and neuropathic pain. The percentage of decreased arm volume or treatment success was better in kinesio-taping group than in the MLD group at the end of the treatment, and at four and 12 weeks after treatment (p = 0.009, p = 0.039, and p = 0.042, respectively). Conclusion: Kinesio-taping led to better results than MLD and was similarly effective compared with low-level laser in stage II breast cancer-related lymphedema at the twelfth week of follow-up. Kinesio-taping and low-level laser should be considered as alternative treatments in early-moderate stages of lymphedema. After these modalities, multi-layer compression and compression bandaging remain cornerstones of lymphedema treatment.Article Citation - WoS: 2Citation - Scopus: 2Synthesis, Properties, and Electrochemistry of a Photochromic Compound Based on Dithienylethene and Prodot(Tubitak Scientific & Technological Research Council Turkey, 2015) Algi, Melek Pamuk; Cihaner, Atilla; Algi, FatihThe synthesis, photochromic features, and electrochemistry of a novel material based on dithienylethene (DTE) and 3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine (didecyl-ProDOT) units are described. It is noteworthy that 1,2-bis (5-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-2-methylthiophen-3-yl)cyclopent-1-ene can be efficiently switched between open and closed states by light in both solution and in the solid poly(methyl metacrylate) (PMMA) matrix. It is also found that the emission of this novel compound can be switched on and off upon irradiation.Conference Object Measuring Complexity of Object Oriented Programs(2008) Misra,S.; Akman,I.In this paper, a metric for object oriented language is formulated and validated. On the contrary of the other metrics used for object oriented programming (OOPs), the proposed metric calculates the complexity of a class at method level and hence considers the internal architecture of the classes, subclasses and member functions. The proposed metric is evaluated against Weyuker's proposed set of measurement principles through examples and validated through experimentation, case study and comparative study with similar measures. The practical usefulness of the metric is evaluated by a practical framework. © 2008 Springer-Verlag Berlin Heidelberg.
