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    Biosynthesis of gold nanoparticles using marine bacteria and Box-Behnken design optimization
    (Taylor & Francis Inc, 2019) Camas, Mustafa; Celik, Fatih; Camas, Anil Sazak; Ozalp, Hasan Baris
    Gold nanoparticles are exciting materials because of their potential applications in optics, electronics, biomedical, and pharmaceutical fields. In recent years, environmentally friendly, low-cost biosynthesis methods with bio-applicable features have continued to be developed for the synthesis of gold nanoparticles. In the present study, an actinobacterial strain was isolated from the Petrosia ficiformis (Poiret 1798) sponge, which was collected from a marine environment, and the gold nanoparticle synthesis was performed for the first time from the bacteria type belonging to the Citricoccus genus. The synthesis conditions were optimized using the Box-Behnken experimental design, with a statistical method that included three independent variables (temperature, time, and mixture ratio) to affect the synthesis at three levels (+1, 0, and -1). Accordingly, the conditions proposed for the biosynthesis of gold nanoparticles at the maximum optical density values that are specific for the Citricoccus sp. K1D109 strain were estimated as 35 degrees C temperature, 24 h, and 1/5 mixture ratio (cell-free extract/HAuCl4 center dot 3H(2)O). When recommended conditions were applied, it was determined that the maximum absorbance of the synthesized gold nanoparticles is 1.258 at 545 nm, and their sizes are in the range of 25-65 nm, according to transmission electron microscopy (TEM) data.
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    Does three-dimensional prenatal ultrasound necerrasy: pregnant women's point of view
    (Via Medica, 2014) Koken, Gulengul; Gungor, Ayse Nur Cakir; Celik, Fatih; Batmaz, Gonca; Unlu, Serdar; Arioz, Dagistan; Yilmazer, Mehmet
    Objectives: The role and applicability of three-dimensional ultrasound (3D-US) in perinatology has been repeatedly discussed in the literature. Regardless, our knowledge about patient expectations remains limited. We aimed at determining the expectations, perception and knowledge of pregnant women about 3D-US. Material and Methods: Upon admission to the labor unit, the women filled out a questionnaire, with the help of a doctor, investigating sociodemographic data, pregnancy and delivery history previous experiences and expectations for US imaging. Results: A total of 644 pregnant women were included in the study Respondents declared that approximately 70% of all kinds of structural abnormalities could be detected by 3D-US and estimated its reliabilityat nearly 70%. While 60% of the participants underwent 3D-US, 70% of them believed that every pregnant woman should undergo such test. Also, 457 (70.9%) of the participants were of the opinion that every pregnant woman must undergo 3D-US imaging, whereas 173 (26.8%) did not think 3D-US imaging was necessary Conclusions: To the best of our knowledge, this has been the first study on patient opinions regarding the need for 3D-US imaging during pregnancy Although the participants were not certain about the harmful effects of 3D-US, the majority believed that it was necessary for every pregnant woman to undergo such testing. Obviously patients must be instructed on the limitations of US imaging before the examination to clarify any misunderstandings about the possibilities such a technique may offer.
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    Uranium (VI) Biosorption on Marine Sponge, Sarcotragus foetidus (Schmidt, 1862) and Its Statistical Investigation Using Central Composite Design
    (Central Fisheries Research Inst, 2016) Celik, Fatih; Camas, Mustafa; Camas, Anil Sazak; Ozalp, Hasan Baris
    The biosorption of heavy metals, radionuclides, uranium and thorium for the recovery or removal from aqueous systems using various micro-organisms and biological substances has been investigated by several groups of workers. In this paper, the uptake of uranium (VI) from aqueous systems by a marine sponge, Sarcotragus foetidus (Schmidt, 1862) has been investigated. S. foetidus samples were collected from Babakale/Ayvacik/Canakkale in Turkey. Uranium (VI) uptake experiments were carried out by the batch technique. The affecting parameters were analyzed using Central Composite Design (CCD) as the experimental method. Four independent variables such-pH, temperature, contact time, and initial uranium concentration were selected for this study. The influences of initial pH, contact time, and initial uranium concentration on the biosorption process were considered statistically significant as main effects. On the other hand, interaction effects of pH and contact time, as well as pH and initial uranium concentration, were considered as significant parameters on the biosorption process. The optimum condition of biosorption process was found to be at initial pH: 4, temperature: 35 degrees C, initial uranium concentration: 20 mg/L, and contact time: 31 minutes. At these conditions, the biosorption yield of uranium (VI) ions was obtained to be 93.29 +/- 2%.