Browsing by Author "Topal A."

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    Use of recycled concrete aggregates in Hot-Mix Asphalt
    (American Concrete Institute, 2006) Topal A.; Öztürk A.U.; Baradan B.
    The rubble from construction is generally used in landfill or thrown to natural areas at the end of their service life. Because continuously increasing production of concrete consumption, recycling of concrete waste materials will provide environmental protection and economical benefits. In this study, effects of fine and coarse recycled concrete aggregates on Hot-Mix Asphalt (HMA) performance were investigated. In performed experiments, Marshall Mixtures were prepared by using recycled concrete aggregates in the proportion of 10%, 20%, and 30% by mixture weight for the replacement of limestone in suitable gradation. Six different bitumen ratios were added to each mixture, respectively. Void %, flow and stability values were examined on 54 specimens. Furthermore, indirect tensile strength experiments were examined on the specimens having optimum 4.5% bitumen content and 30% recycled concrete aggregates. The results indicate that waste concrete can be used in HMA as aggregate to obtain the required Marshall stability and indirect tensile strength of the mixtures. However, the void percent of the mixture are not desirable due to the dense gradation of aggregate. Hence, gradation change is needed to Marshall Design criteria. © 2006 American Concrete Institute. All rights reserved.
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    Preparation and Performance Testing of SBS Modified Bitumens Reinforced with Halloysite and Sepiolite Nanoclays
    (Turkish Chamber of Civil Engineers, 2022) Uncu D.; Topal A.; Seydi̇Beyoğlu M.Ö.
    In this study, halloysite and sepiolite nanoclays were used to reinforce SBS modified bitumens. The nanoclays used are different from the materials in the literature and have properties such as easy to find, economical and available from local sources. The mixing parameters were determined before production process. The polymer additive SBS was added into base bitumen at 3% and 5%, while the nanoclay additives were added into polymer modified bitumen at 2% and 4% ratios. The morphological structures were investigated under fluorescence microscope. Physical and rheological properties of the samples were compared. The phase separation cases were investigated by storage stability test. Furthermore, rutting performance of samples was measured with zero shear viscosity (ZSV) and multi stress creep recovery (MSCR) test methods. © 2022 Turkish Chamber of Civil Engineers. All rights reserved.
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    Efficacy of first-line CDK 4-6 inhibitors in premenopausal patients with metastatic breast cancer and the effect of dose reduction due to treatment-related neutropenia on efficacy: a Turkish Oncology Group (TOG) study
    (Taylor and Francis Ltd., 2025) Yildirim H.C.; Kapar C.; Koksal B.; Seyyar M.; Sanci P.C.; Guliyev M.; Perkin P.; Buyukkor M.; Yaslikaya S.; Majidova N.; Keskinkilic M.; Ozaskin D.; Avci T.; Gunes T.K.; Arcagok M.; Topal A.; Keskin G.S.Y.; Kavgaci G.; Yildirim N.; Celayir O.M.; Avci N.; Aslan F.; Alkan A.; Erciyestepe M.; Cengiz M.; Pehlivan M.; Gulmez A.; Beypinar I.; Basoglu Tuylu T.; Kayikcioglu E.; Chalabiyev E.; Turhal S.; Guzel H.G.; Ayas E.; Sahbazlar M.; Dulgar O.; Demir H.; Yavuzsen T.; Bayoglu V.; Kivrak Salim D.; Ozturk B.; Ozdemir F.; Kara O.; Oksuzoglu B.; Bal O.; Demirci N.S.; Yilmaz M.; Cabuk D.; Aksoy S.
    The only phase 3 study on the effectiveness of CDK 4-6 inhibitors in first-line treatment in premenopausal patients with hormone receptor (HR) positive, HER2 negative metastatic breast cancer is the MONALEESA-7 study, and data on the effectiveness of palbociclib is limited. Data are also limited regarding the effectiveness of CDK 4-6 inhibitors in patients whose dose was reduced due to neutropenia, the most common side effect of CDK 4-6 inhibitors. In our study, we aimed to evaluate the effectiveness of palbociclib and ribociclib in first-line treatment in patients with premenopausal metastatic breast cancer and the effect of dose reduction due to neutropenia on progression-free survival. Our study is a multicenter, retrospective study, and factors affecting progression-free survival (PFS) were examined in patients diagnosed with metastatic premenopausal breast cancer from 29 different centers and receiving combination therapy containing palbociclib or ribociclib in the metastatic stage. 319 patients were included in the study. The mPFS for patients treated with palbociclib was 26.83 months, and for those receiving ribociclib, the mPFS was 29.86 months (p = 0.924). mPFS was 32.00 months in patients who received a reduced dose, and mPFS was 25.96 months in patients who could take the initial dose, and there was no statistical difference (p = 0.238). Liver metastasis, using a fulvestrant together with a CDK 4-6 inhibitor, ECOG PS 1 was found to be a negative prognostic factor. No new adverse events were observed. In our study, we found PFS over 27 months in patients diagnosed with premenopausal breast cancer with CDK 4-6 inhibitors used in first-line treatment, similar to post-menopausal patients. We did not detect any difference between the effectiveness of the two CDK 4-6 inhibitors, and we showed that there was no decrease in the effectiveness of the CDK 4-6 inhibitor in patients whose dose was reduced due to neutropenia. © 2024 Edizioni Scientifiche per l'Informazione su Farmaci e Terapia (Italian Society of Chemotherapy).