Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Kent İçi Arkeolojik Alanlarda Katmanlaşmanın Analizi ve Koruma Sorunları: Foça Örneği(Türk Tarih Kurumu, 2018) Taşcı, Burcu; Akyüz Levi, EtiFoça Batı Anadolu’da Prehistorik dönemden başlayarak Arkaik, Klasik, Helenistik, Roma, Bizans, Ceneviz kolonisi ve Osmanlı dönemlerinde sürekli iskân görmüş, çok katmanlı bir yerleşimdir. Kentte arkeolojik kazı çalışmaları 20. yüzyıl başından günümüze aralıklarla devam etmektedir. Üçüncü dönem kazı çalışmaları Prof. Dr. Ömer Özyiğit başkanlığında 1989 yılından beri sürmektedir. Modern Foça kenti, tarihi yaklaşık M.Ö. 3000’lere dek uzanan antik Phokaia kentinin üstünde bir katman olarak bulunmakta ve kazı çalışmaları da kent içi arkeolojik alanlarda yoğunlaşmaktadır. Kentin tarihi katmanlaşmasında en üst tabaka olarak Osmanlı dönemi sivil mimarlık örnekleri öne çıkmaktadır. Bununla birlikte modern kent dokusunu az katlı, niteliksiz betonarme yapılar oluşturmaktadır. Kentte ilk sit kararlarının belirlendiği 1977 yılından günümüze dek sit sınırları pek çok kez değişmiş ve bu durum yeni yapılaşmanın önünü açmıştır. Özellikle turizmin ve ikincil konut yapımının artması ise kültür varlıklarına zarar vermiştir. Bu olumsuz durum kent içi arkeolojik alanlarda katmanlaşmanın zarar görmemesi için farklı yaklaşımlara gereksinim duyulduğunu göstermektedir. Kentsel arkeoloji çalışmaları bu gereksinime yanıt verecek nitelikte olup, kapsamlı tarih araştırmaları ile desteklenen kazı çalışmalarında ortaya çıkan verilerin, kentlerin koruma, planlama ve gelişim süreçlerine eklenmesini öngörmektedir.Article Citation - WoS: 42Citation - Scopus: 48The Roles of Bioactive Sphingolipids in Resveratrol-Induced Apoptosis in Hl60 Acute Myeloid Leukemia Cells(Springer Verlag, 2011) Çakır, Zeynep; Saydam, Güray; Şahin, Fahri; Baran, YusufPurpose Acute promyelocytic leukemia results from a translocation between 15 and 17 chromosomes that produce PML/RARa fusion protein. PML/RARa inhibits differentiation of myeloid precursor cells at stem cell level. Resveratrol is a phytoalexin that exerts cytotoxic effects on cancer cells. Ceramides have crucial roles in cell growth, proliferation, differentiation, drug resistance, and apoptosis. In this study, we examined the possible cytotoxic effects of resveratrol on acute myeloid leukemia cells and determined the roles of ceramide-metabolizing genes in resveratrol-induced apoptosis, in addition to investigating the possibility of increasing the sensitivity of HL60 cells to resveratrol by manipulating sphingolipids. Methods Cytotoxic effects of resveratrol, C8:ceramide, PDMP, and SK-1 inhibitor were determined by XTT cell proliferation assay. Changes in caspase-3 enzyme activity and mitochondrial membrane potential (MMP) were measured using caspase-3 colorimetric assay and JC-1 MMP detection kit. Expression levels of ceramide-metabolizing genes were examined by RT-PCR. Results The results revealed that manipulations of ceramide metabolism toward generation or accumulation of apoptotic ceramides increased apoptotic effects of resveratrol in HL60 cells, synergistically. More importantly, gene expression analyses revealed that resveratrol-induced apoptosis via increasing expression levels of ceramide generating genes and decreasing expression levels of antiapoptotic sphingosine kinase-1 and glucosylceramide synthase genes. Conclusion These results showed for the first time that increasing intracellular levels of ceramides by biochemical approaches has also increased sensitivity of HL60 cells to resveratrol. We also showed that resveratrol induces apoptosis through manipulating ceramide-metabolizing genes that resulted in the accumulation of ceramides in HL60 cells.Article Citation - WoS: 3Citation - Scopus: 2Prediction of Microdrill Breakage Using Rough Sets(Cambridge University Press, 2011) Sevil, Hakkı Erhan; Özdemir, SerhanThis study attempts to correlate the nonlinear invariants’ with the changing conditions of a drilling process through a series of condition monitoring experiments on small diameter (1 mm) drill bits. Run-to-failure tests are performed on these drill bits, and vibration data are consecutively gathered at equal time intervals. Nonlinear invariants, such as the Kolmogorov entropy and correlation dimension, and statistical parameters are calculated based on the corresponding conditions of the drill bits. By intervariations of these values between two successive measurements, a drop–rise table is created. Any variation that is within a certain threshold (+-20% of the measurements in this case) is assumed to be constant. Any fluctuation above or below is assumed to be either a rise or a drop. The reduct and conflict tables then help eliminate incongruous and redundant data by the use of rough sets (RSs). Inconsistent data, which by definition is the boundary re-gion, are classified through certainty and coverage factors. By handling inconsistencies and redundancies, 11 rules are ex-tracted from 39 experiments, representing the underlying rules. Then 22 new experiments are used to check the validity of the rule space. The RS decision frame performs best at predicting no failure cases. It is believed that RSs are superior in dealing with real-life data over fuzzy set logic in that actual measured data are never as consistent as here and may dominate the monitoring of the manufacturing processes as it becomes more widespread.