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  • Article
    Citation - WoS: 15
    Citation - Scopus: 17
    Pei Modifiednatural Sands of Florida as Catalysts for Hydrogen Production From Sodium Borohydride Dehydrogenation in Methanol
    (Wiley-hindawi, 2021) Inger, Erk; Demirci, Sahin; Can, Mehmet; Sunol, Aydin K.; Philippidis, George; Sahiner, Nurettin
    Sand samples from Tampa (T) and Panama (P) City beaches in Florida were used as catalysts for dehydrogenation of NaBH4 in methanol. T and P sand samples were sieved to <250, 250 to 500, and >500 mu m sizes, and the smallest fractions resulted in faster hydrogen generation rates (HGR), 565 +/- 18 and 482 +/- 24 mL H-2 (min.g of catalyst)(-1), respectively. After various base/acid treatments, HGR values of 705 +/- 51 and 690 +/- 47 mL H-2 (min g of catalyst)(-1) for HCl-treated T and P sand samples were attained, respectively. Next, T and P sand samples were modified with polyethyleneimine (PEI) that doubled the HGR values, 1344 +/- 103, and 1190 +/- 87 mL H-2 (min.g of catalyst)(-1) and increased similar to 8-fold, 4408 +/- 187, and 3879 +/- 169 mL H-2 (min g of catalyst)(-1), correspondingly after protonation (PEI+). The Ea values of T and P sand samples were calculated as 24.6 and 25.9 kJ/mol, and increased to 36.1, and 36.6 kJ/mol for T-PEI(+)and P-PEI(+)samples, respectively.
  • Article
    Citation - WoS: 56
    Citation - Scopus: 58
    Reliability Analysis Under Marshall-Olkin Run Shock Model
    (Elsevier, 2019) Ozkut, Murat; Eryilmaz, Serkan
    In this paper, a new shock model called Marshall-Olkin run shock model is defined and studied. According to the model, two components are subject to shocks that may arrive from three different sources, and component i fails when it is subject to k consecutive critical shocks from source i or k consecutive critical shocks from source 3, i = 1, 2. Reliability and mean residual life functions of such components are studied when the times between shocks follow phase-type distribution. (C) 2018 Elsevier B.V. All rights reserved.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 10
    The Role of Environmental Factors in the Investment Prioritization of Facilities Using Recycled Pvc
    (Hard, 2021) Bac, Ugur
    There 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: 5
    Citation - Scopus: 5
    Aptamer decorated PDA@magnetic silica microparticles for bacteria purification
    (Springer Wien, 2024) Kavruk, Murat; Babaie, Zahra; Kibar, Gunes; Cetin, Barbaros; Yesilkaya, Hasan; Amrani, Yassine; Ozalp, V. Cengiz
    One significant constraint in the advancement of biosensors is the signal-to-noise ratio, which is adversely affected by the presence of interfering factors such as blood in the sample matrix. In the present investigation, a specific aptamer binding was chosen for its affinity, while exhibiting no binding affinity towards non-target bacterial cells. This selective binding property was leveraged to facilitate the production of magnetic microparticles decorated with aptamers. A novel assay was developed to effectively isolate S. pneumoniae from PBS or directly from blood samples using an aptamer with an affinity constant of 72.8 nM. The capture experiments demonstrated efficiencies up to 87% and 66% are achievable for isolating spiked S. pneumoniae in 1 mL PBS and blood samples, respectively.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Incidence 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, Engin
    Introduction:
    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.
  • Article
    Citation - WoS: 5
    Evaluation of the Efficacy of Silymarin and Dexmedetomidine on Kidney and Lung Tissue in the Treatment of Sepsis in Rats With Cecal Perforation
    (Spandidos Publ Ltd, 2024) Yavuz, Aydin; Kucuk, Aysegul; Ergorun, Aydan Iremnur; Dursun, Ali Dogan; Yigman, Zeynep; Alkan, Metin; Arslan, Mustafa
    Sepsis is a systemic inflammatory response syndrome that develops in the host against microorganisms. This response develops away from the primary infection site and results in end-organ damage. The present study aimed to investigate the protective and therapeutic effects on lung and kidney tissue of silymarin (S) and dexmedetomidine (DEX) applied 1 h before and after sepsis induced by the cecal ligation and puncture (CLP) method in rats. A total of 62 rats was randomly divided into eight groups: i) Control (n=6); ii) cecal perforation (CLP; n=8); iii) S + CLP (n=8; S + CLP; S administered 1 h before CPL); iv) CLP + S (n=8; S administered 1 h after CLP); v) DEX + CLP (n=8; D + CLP; DEX administered 1 h before CLP); vi) CLP + D (n=8; DEX administered 1 h after CLP); vii) SD + CLP (n=8; S and DEX administered 1 h before CLP) and viii) CLP + SD (n=8; S and DEX administered 1 h after CLP). After the cecum filled with stool, it was tied with 3/0 silk under the ileocecal valve and the anterior surface of the cecum was punctured twice with an 18-gauge needle. A total of 100 mg/kg silymarin and 100 mu g/kg DEX were administered intraperitoneally to the treatment groups. Lung and kidney tissue samples were collected to evaluate biochemical and histopathological parameters. In the histopathological examination, all parameters indicating kidney injury; interstitial edema, peritubular capillary dilatation, vacuolization, ablation of tubular epithelium from the basement membrane, loss of brush border in the proximal tubule epithelium, cell swelling and nuclear defragmentation; were increased in the CLP compared with the control group. Silymarin administration increased kidney damage, including ablation of tubular epithelium from the basement membrane, compared with that in the CLP group. DEX significantly reduced kidney damage compared with the CLP and silymarin groups. The co-administration of DEX + silymarin decreased kidney damage, although it was not as effective as DEX-alone. To conclude, intraperitoneal DEX ameliorated injury in CLP rats. DEX + silymarin partially ameliorated injury but silymarin administration increased damage. As a result, silymarin has a negative effects with this dosage and DEX has a protective effect. In the present study, it was determined that using the two drugs together had a greater therapeutic effect than silymarin and no differences in the effects were not observed any when the application times of the agents were changed.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 3
    Modeling of Asymmetric Shear Wall-Frame Building Structures
    (Architectural inst Japan, 2009) Akis, Tolga; Tokdemir, Turgut; Yilmaz, Cetin
    Based on the conventional wide column analogy, two different three-dimensional shear wall models for open and closed sections are proposed. These approximate models are verified in comparison to not only the results available in the literature but also the ones obtained by Using models containing shell elements. With the help of these new models five different groups of shear wall-frame structures with different floor plans and different heights are analyzed. The first three natural vibration periods are determined and time history analyses are performed. The results Of these computations are observed to be in good agreement with those obtained by detailed models containing shell elements.
  • Article
    Citation - WoS: 18
    Citation - Scopus: 19
    A Generalization of Ciric Quasicontractions
    (Hindawi Publishing Corporation, 2012) Karapinar, Erdal; Kieu Phuong Chi; Tran Duc Thanh
    We 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: 10
    Citation - Scopus: 9
    The 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 Figen
    Objective: 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: 2
    Citation - Scopus: 2
    Synthesis, 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, Fatih
    The 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.