25 results on '"Korkmaz, Büşra"'
Search Results
2. Evaluation of cariogenic and erosive potential of prescribed pediatric medicaments in Northeast of Turkey: An in vitro study
- Author
-
YILMAZ, Nagehan, primary, KORKMAZ, Büşra, additional, ERBEK, Şengül, additional, BAYGİN, Ozgul, additional, KORKMAZ, Fatih Mehmet, additional, and TUZUNER, Tamer, additional
- Published
- 2022
- Full Text
- View/download PDF
3. Antimicrobial and lipase inhibition of essential oil and solvent extracts of Cota tinctoria var. tinctoria and characterization of the essential oil
- Author
-
ERİK, İSHAK, primary, BOZDAL, GÖZDE, additional, ŞENER, SILA ÖZLEM, additional, KORKMAZ, BÜŞRA, additional, KARAOĞLU, ŞENGÜL ALPAY, additional, TERZİOĞLU, SALİH, additional, and YAYLI, NURETTİN, additional
- Published
- 2022
- Full Text
- View/download PDF
4. Karaciğer kanserinde ilaç taramalari için in vivo model olarak zebra baliğinin incelenmesi: fenotiyazinlerin rolü
- Author
-
Korkmaz, Büşra and Karakayalı, Özlen Konu
- Subjects
Cholesterol ,Hepatocellular carcinoma ,Phenothiazines ,Xenograft ,Drug repurposing ,Sorafenib ,Zebrafish ,In vivo drug screening - Abstract
Cataloged from PDF version of article. Thesis (Master's): Bilkent University, Department of Molecular Biology and Genetics, İhsan Doğramacı Bilkent University, 2021. Includes bibliographical references (leaves 103-113). Hepatocellular carcinoma (HCC) is one of the most dangerous cancer types and sorafenib (SFB) is a commonly used drug against HCC, being the only FDA-approved medication until 2018. However, its limited efficacy and severe side effects emphasize the importance of developing alternative approaches. Regulation of cholesterol has been implicated in the progression of various cancers including HCC. Phenothiazines, which are in use as antipsychotic drugs and with effects on cholesterol biosynthesis, have drawn recent attention as anti-cancer drugs against different cancers. The elucidation of how phenothiazines exert their effects at cellular level might pave the way for proposing better strategies for HCC treatment. Zebrafish serves as a good cancer model for in vivo validations, since it enables efficient tumor formation and tracking. Its conserved genes and similar organ system to human make it even better of a model to reveal both molecular and morphological alterations caused by drugs. Based on previous cell viability studies from our lab, the combination of trifluoperazine (TFP) with SFB was found to exhibit synergism in Hep3B cells, while it was antagonistic in SkHep1 cells. Moreover, RNA-seq analysis on Hep3B cells has demonstrated that steroid biosynthesis and cholesterol metabolism was among the modulated pathways. Therefore, in the present thesis, the regulation of cholesterol levels in response to phenothiazine derivatives was investigated in HCC cell lines SkHep1 and Hep3B. The combinatorial approach was examined on Huh7 cells in terms of the expression of cholesterol biosynthesis genes based on RT-qPCR. After showing the ability of phenothiazine derivatives and TFP-SFB combinations to modulate cellular cholesterol, zebrafish drug screens were performed to determine applicable derivative and combination doses. Assessment of safe doses for TFP, SFB and their combination directed us for xenograft studies, which resulted in enhanced Hep3B cell survival by the combination of low dose (6 μM) TFP and 1 μM of SFB. This finding was further validated based on Alu-based DNA quantifiation, a powerful method we have established. With the help of RNA-seq analysis results, orthologous zebrafish genes, involved in cholesterol biosynthesis were identified and used in cross-species testing. The impact of TFP on liver vasculature was evaluated using transgenic (Fli1a:EGFP) zebrafish and found insignificant. Overall, the findings presented in this thesis highlight that TFP alone or in combination was able to change cellular cholesterol levels and tumor growth. by Büşra Korkmaz M.S.
- Published
- 2021
5. SHIGERU BAN AND 'TEMPORARY SHELTER' CONCEPT
- Author
-
ÖZCAN, Uğur, GÜLER, Betül, and KORKMAZ, Büşra
- Subjects
Social ,Sustainable Architecture,Earthquake,Temporary Shelter,Shigeru Ban ,Sürdürülebilir Mimarlık,Deprem,Geçici Barınak,Shigeru Ban ,Sosyal - Abstract
Doğal afetler, insan yaşamında olumsuz etkilere sebep olmaktadır. Ne zaman meydana geleceği öngörülemeyen doğal afetlerin olası sonuçlarına karşı, her zaman tedbirli olmak gerekmektedir. Afet anında, öncesinde ve sonrasında pek çok sorun ile karşılaşılsa da bunlardan en önemlisi 'barınacak yer' sorunudur. Çünkü deprem, sel, kasırga gibi yıkıcı sonuçlar doğuran doğal afetler, insanların en temel ihtiyaçlarından birisi olan barınma ihtiyacının karşılanamamasına sebep olabilmektedir. Genellikle, yardım kuruluşları tarafından dağıtılan, çadır tipi ba-rınaklar, tüm ihtiyaçlara cevap verebilecek ve uzun süreli kullanımlarda konfor sağlayabilecek nitelikte değildir. Bu sebeple, mevcut koşullara uyum sağlayabi-lecek şekilde tasarlanmış olan 'geçici barınaklar' ön plana çıkmaktadır. Bu barı-nakların, acil durumlarda hızlıca inşa edilebilir özellikte olması gerekmektedir. Dolayısıyla, yapımında basit çözümler ve ekonomik yöntemlerle, kolay ulaşılabi-lir malzemelerden faydalanılması önem teşkil eder. Geri dönüştürülebilir ve sür-dürülebilir tasarımları ile adından sıkça söz ettiren ünlü mimar Shigeru Ban, afet sonrası ihtiyaçlar sonucunda tasarladığı barınak sistemleriyle, afet bölgelerinde yaşanılan barınak sorununa da çözüm üretmiştir. Tasarımlarını oluştururken afet-lerin meydana geldiği bölgede bulunabilecek malzemeleri, bölgenin iklimini ve bölge halkının kültürünü göz önünde bulunduran mimar, barınakların inşa süre-cinde yerel halkın katıldığı, katılımcı üretim biçimine önem vermiştir. Bu sayede barınakların tasarımında olduğu kadar, inşa aşamasında da sürdürülebilirliğin sağlanması mümkün olmaktadır. İnşa faaliyetlerine katılan yerel halk, geçici ba-rınak konusunda bilinç, yapım yöntemleri konusunda bilgi ve beceri kazanmak-tadır. Bu çalışma kapsamında, Ban'ın farklı afet bölgeleri için tasarladığı, farklı barınak tipleri incelenmiş, bu inceleme sonucunda, söz konusu örneklerin ortak noktaları belirlenmiştir. Seçilen geçici barınak tasarımlarının yapım yöntemleri benzer ol-makla birlikte, yerel özelliklere bağlı olarak farklılıklar da göstermektedir. Ça-lışmada ele alınan örneklerin, afet sonrası istenmeyen bir durum oluşması halin-de, yaşanabilecek barınma problemlerine geçici çözümler olabileceği düşünül-mektedir. Bu barınakların üretim yöntemlerinin basit eğitim faaliyetleri ile öğre-tilmesi ve üretime yerel katılım bilincinin sağlanması, afet sonrasında elde olabi-lecek en etkili toplumsal avantajlardan biri olacaktır., Natural disasters cause adverse impact on human life. It is always necessary to be cautious about the possible consequences of natural disasters that cannot be predicted as to when they will occur. Even though many problems are encoun-tered during, before and after the disaster, the most important of these problems is ‘sheltering’. Because natural disasters such as earthquakes, floods, and hurri-canes, that have destructive outcomes, can result in the failure to provide shelter which is one of the most fundamental needs of human beings. Tent type shelters, that are usually distributed by charities, are not capable of meeting all needs and providing comfort for long-term use. Therefore, ‘temporary shelters’ that are designed to adapt to existing conditions rise to prominence. It is necessary for these shelters to be rapidly buildable in emergencies. Hence, it is important to benefit from easily accessible materials with simple solutions and economic methods in its construction. Famous architect Shigeru Ban, who has made a name for himself with his recyclable and sustainable designs, has also generated a solution for sheltering problems in disaster areas, with a sheltering system he designed as a result of post-disaster needs. He considered the materials that can be found in the region where the disaster occurred, climate of the region, and the culture of the local people while creating his design. He emphasized the partici-patory production style that the local people participate in the construction pro-cess of the shelters. Thus, it is possible to provide sustainability in the construc-tion process as well as in the design of the shelters. Local community, that partic-ipate in the construction, gain awareness on temporary sheltering, and knowledge and skills on construction methods. Within the scope of this study, different type of shelters for different disaster areas designed by Ban were ana-lyzed, and as a result of this analysis common points of these examples were es-tablished. While the construction methods of the chosen temporary shelter de-signs are similar, they also differ depending on local characteristics. It is thought that the examples discussed in the study can be temporary solutions to the shel-tering problems that may be experienced in the event of an undesirable situation after a disaster. Teaching the production methods of these shelters with simple educational activities and providing awareness of local participation in the pro-duction will be one of the most effective social advantages that can be obtained after the disaster.
- Published
- 2021
6. Volatile and Phenolic Contents, Antimicrobial and Tyrosinase activities of Two Endemic Species Scorzonera pisidica and Scorzonera sandrasica L. Grown in Turkey
- Author
-
Yaylı, Nurettin, primary, Öksüz, Enes, additional, Korkmaz, Büşra, additional, Erik, İshak, additional, Fandaklı, Seda, additional, Faiz, Özlem, additional, and Coşkunçelebi, Kamil, additional
- Published
- 2021
- Full Text
- View/download PDF
7. Evaluation of the Expenditures Made in the Repairs of the 19th Century Hagia Sophia Mosque and Complex
- Author
-
AKKOYUN, Bayram, KORKMAZ, Büşra, and TORAMAN, Fatma Esra
- Subjects
Architecture ,Ayasofya,onarım,19. yüzyıl,para,tağşiş ,Hagia Sophia,repair,19th century,money,adulteration ,Mimarlık - Abstract
19. yüzyılda Osmanlı Devleti’nde siyasal, toplumsal ve hukuksal birçok alanda, büyük çapta değişim ve dönüşümlerin yaşanmaya başladığı görülmektedir. Devletin ve halkın yaşamış olduğu sıkıntılar, reformların hayata geçirilmesi ihtiyacını doğurmuştur. 1839 yılında Tanzimat Fermanı’nın ilan edilmesiyle devlet işleyişinde Batı modeli tercih edilmiş ve büyük reformlar yapılmıştır. Devlet mali açıdan büyük sıkıntılara girmiş olmasına rağmen, eldeki belgelerden yola çıkılarak, Ayasofya Camii ve Külliyesi’ne kapsamlı onarımlar yapıldığı bilinmektedir. Bu durum, Ayasofya’nın ne denli önemsendiğini ispatlar niteliktedir. Onarımlar boyunca yapılan harcamaların büyüklüğünü anlayabilmek adına, tarihsel süreç içerisinde değişmeyen bir iş kolu seçilmiş ve düz inşaat işçisinin günlük kazancı üzerinden bir inceleme yapılarak; 19. yüzyılda Ayasofya Camii ve Külliyesi’nde yapılan onarımların maliyet karşılaştırması bir tablo halinde oluşturulmaya çalışılmıştır., In the 19th century, it is seen that large-scale changes and transformations began to occur in many political, social and legal areas in the Ottoman State. The difficulties experienced by the state and the public, led to the need for reforms to be implemented. With the proclamation of the Tanzimat edict in 1839, the Western model was preferred in state which led to the proclamation of major reforms. Although the state was in great financial difficulties, it is known that extensive amounts were spent for the Hagia Sophia Mosque and complex, based on the documents available. This proves the significance of Hagia Sophia for the Ottoman State. In order to understand the amount of the expenses incurred during the repairs, the daily earnings of an ordinary construction worker, as a line of position that remained constant in the historical process, had been selected and a review had been carried out. Thus, it was possible to prepare a table comparing the expenses for the repairs of Hagia Sophia Mosque and Complex.
- Published
- 2021
8. Evaluation of cariogenic and erosive potential of prescribed pediatric medicaments in Northeast of Turkey: An in vitro study
- Author
-
YILMAZ, Nagehan, KORKMAZ, Büşra, ERBEK, Şengül, BAYGİN, Ozgul, KORKMAZ, Fatih Mehmet, and TUZUNER, Tamer
- Subjects
Diş Hekimliği ,Erozyon ,Mine ,Oral likit ilaç ,Dental ,Erosion ,Enamel ,Oral liquid medicament - Abstract
Amaç: Çalışmanın amacı, Türkiye Kuzeydoğu bölgesinde pediatrik kullanım için reçete edilen ilaçların karyojenik ve eroziv potansiyelini in vitro olarak değerlendirilmesidir. Gereç ve yöntem: Çalışmada pediatristler tarafından reçete edilen ilaçlar arasından 14 farklı ilaç grubuna ait 30 farklı ilaç seçildi. İlaçların pH, total titrasyon asitliği (TTA), toplam çözünebilir katı içeriği (TSSC), toplam şeker içeriği (TSC) ölçüldü. Elde edilen veriler SPSS istatistik yazılımı kullanılarak analiz edildi. Tüm gruplarda pH ve TTA, TSSC değerleri açısından karşılaştırma yapılırken Pearson ki-kare testi uygulandı. Bulgu:Test edilen ilaçların pH ortanca değerleri 3.11 ile 7.62 arasında değiştiği; ilaçların % 53.3’nün pH ortanca değerinin kritik pH (5.5) in altında olduğu tespit edildi. Ortanca değere göre TTA değerleri tüm gruplarda düşük olarak bulgulandı. En yüksek TTA değeri 23.8770 ve ikinci olarak 22.9540 olarak ölçüldü. En düşük TSSC değerinin 1.3320 ve en yüksek TSSC değerinin 1.4450 olduğu saptandı. Toplam şeker içerikleri analizinde kullanılan ilaçların %33 ‘ünde şeker içeriği tespit edildi. Sonuç: Analiz edilen ilaçlar, diş dokularında karyojenik ve eroziv potansiyel gösteren fizikokimyasal özellikler gösterdi. Bu doğrultuda sağlık profesyonelleri, ilaç üreticileri ve ebeveynler diş dokularına potansiyel olarak zararlı ilaçların tüketilmesinden kaynaklanan riskler hakkında bilinçlendirilmelidir., Aim: To purpose of the present study is to evaluate in vitro the cariogenic and erosive potential of the medicaments prescribed for pediatric use in the Northeastern Region of Turkey. Material and Methods: In the present study, 30 different medicaments of 14 different drug groups were selected among the medicaments prescribed by pediatricians. The pH, Total Titration Acidity (TTA), Total Soluble Solid Content (TSSC), Total Sugar Content (TSC) of the medicaments were measured. The data obtained in this way were analyzed by using the SPSS Statistics Software. The Pearson Chi-Square Test was used in all groups when comparing the pH, TTA and TSSC values. Results: It was determined that the median pH values of the medicaments that were tested ranged between 3.11 and 7.62; and 53.3 % of the medicaments had pH levels below the critical median value (5.5). It was found that the TTA values were low in all groups according to the median value. The highest TTA value was measured 23.8770 and the second was 22.9540.The lowest TSSC was found to be 1.3320, and the highest TSSC was 1.4450. Sugar content was detected in 33 % of the medicaments that were used in total sugar content analysis. Conclusions: The medicaments that were analyzed showed physical chemical properties showing cariogenic and erosive potentials in dental tissues. In this respect, healthcare professionals, drug manufacturers, and parents must be informed about the risks caused by the consumption of potentially harmful medicaments in dental tissues.
- Published
- 2021
9. Chemical variation, antimicrobial, nitric oxide scavenging activities and tyrosinase inhibition of essential oils and solvent extracts from filipendula vulgaris moench growing in Turkey
- Author
-
Fandaklı, Seda, Korkmaz, Büşra, Faiz, Özlem, Kılıç, Gözde, Erik, İshak, Terzioğlu, Salih, Yaylı, Nurettin, RTEÜ, Fen - Edebiyat Fakültesi, Kimya Bölümü, and Faiz, Özlem
- Subjects
Biological activity ,Filipendula vulgaris ,SPME ,MS ,GC-FID ,Essential oil - Abstract
Volatile organic compositions of the essential oils (EOs), solid-phase microextraction (SPME) and SPME of n-hexane extracts from the flower and stem-leaf of Filipendula vulgaris (F. vulgaris) were analyzed by GC-FID/MS. A total of 107 constituents were characterized, flower and stem leaf parts of the plant were found to contain different volatile organic compounds. Tricosane (29.6%), n-nonanal (20.5%) were identified as the main components in the essential oil of the flower, while phytol (35.2%) was found to be a major constituent in the essential oil of stem-leaf. Benzaldehyde (56.0%) and n-nonanal (31.6%) were the major groups in the SPME of stem-leaf and flower, respectively. The volatiles for the SPME of n-hexane extracts of the flower and stem leaf of F. vulgaris were predominated by aromatic compounds (75.0% and 78.5%) and ketones (18.1% and 10.1%), respectively. On the other hand, a total of terpene compounds was found at the most in the EO of the stem-leaf part of the plant (48.6%). In addition, antimicrobial, tyrosinase inhibition, and nitric oxide scavenging activities of the n-hexane (H), methanol (M), aqueous extracts (A) and EOs of F. vulgaris were investigated. EOs and methanol extracts of flower and stem-leaf had high antimicrobial activity against tested various microorganisms. However, n-hexane extracts of the flower and stem-leaf only displayed activity against Mycobacterium smegmatis. Methanol extracts of flower and stem-leaf possessed the best tyrosine inhibition and NO scavenging activity. Karadeniz Technical University Research Fund KTU-BAP-6714
- Published
- 2021
10. Bir Havayolu İşletmesinde Kabin Ekiplerinin Performans Değerlendirmesine İlişkin bir Veri Madenciliği Uygulaması
- Author
-
ÖZCAN, UĞUR and Yıldız Korkmaz, Büşra
- Subjects
airline ,veri madenciliği ,data mining ,kabin memuru ,performance evaluation ,performans değerlendirme ,lcsh:TA1-2040 ,decision tree ,cabin crew ,lcsh:Q ,karar ağaçları ,lcsh:Engineering (General). Civil engineering (General) ,lcsh:Science ,havayolu - Abstract
Günümüzde işletmeler gerek piyasaya tutunmak gerekse her geçen gün gelişmekte olan teknolojiyi yakalamak adına yoğun bir rekabet içerisindedirler. Yoğun rekabet ortamı mevcut müşteriyi tutma ve yeni müşteri kazanma amacını da beraberinde getirmektedir. Havayolu işletmelerinde yolculara beklentilerinin ötesinde hizmet sunma noktasında kabin ekibinin etkisi büyüktür. Bir havayolu işletmesinde 3764 kabin memurunun 2015 yılında performans değerlendirmeleri incelenmiştir. Yapılan bu performans değerlendirmelerinin sonucunda karne düzeyleri belirlenmektedir. Bu çalışmanın amacı 2015 yılındaki karne düzeyleri için; kabin memurlarının yetkinlik bazlı değerlendirme puanları ile demografik özellikleri arasında anlamlı bir kural oluşturmaktır. Bu çalışmada, açık kaynak kodlu JAVA dilinde geliştirilmiş WEKA programı ile veri madenciliği yöntemlerinden karar ağacı algoritmaları kullanılmıştır. Oluşturulan karar ağacı algoritmalarından sınıflandırma doğruluğu açısından en başarılı algoritma olarak Random Forest ve ikinci olarak J48 algoritması tespit edilmiştir. Random Forest algoritma çıktısı görsel bir sonuç vermeyip algoritma adımlarını görülmeyecek şekilde vererek karmaşık bir yapı oluşmasından dolayı çalışma J48 algoritmasına göre yorumlanmıştır. Ayrıca, WEKA programında nitelik seçimi özelliği ile InfoGainAttributeEval algoritması ile “Ranker” metodu uygulanması sonucunda çıktıların J48 algoritması çıktıları ile aynı doğrultuda olduğu tespit edilmiştir. Bu bağlamda kabin memurlarının karne düzeylerini en çok etkileyen niteliğin “sürekli öğrenme ve kişisel gelişim” olduğu ve demografik özellikler ile karne düzeyi arasında anlamlı kural olmadığı tespit edilmiştir.
- Published
- 2018
11. Bir havayolu işletmesinde kabin ekiplerinin performans değerlendirmesine ilişkin bir veri madenciliği uygulaması
- Author
-
Yildiz Korkmaz, Büşra, Özcan, Uğur, and Endüstri Mühendisliği Anabilim Dalı
- Subjects
Endüstri ve Endüstri Mühendisliği ,Industrial and Industrial Engineering - Abstract
Günümüzde işletmeler gerek piyasaya tutunmak gerekse her geçen gün gelişmekte olan teknolojiyi yakalamak adına yoğun bir rekabet içerisindedirler. Yoğun rekabet ortamı mevcut müşteriyi tutma ve yeni müşteri kazanma amacını da beraberinde getirmektedir. Havayolu işletmelerinde yolculara beklentilerinin ötesinde hizmet sunma noktasında kabin ekibinin etkisi büyüktür. Bir havayolu işletmesinde 3764 kabin memurunun 2015 yılında performans değerlendirmeleri incelenmiştir. Yapılan bu performans değerlendirmelerinin sonucunda karne düzeyleri belirlenmektedir. Bu çalışmanın amacı 2015 yılındaki karne düzeyleri için; kabin memurlarının yetkinlik bazlı değerlendirme puanları ile demografik özellikleri arasında anlamlı bir kural oluşturmaktır. Bu çalışmada, açık kaynak kodlu JAVA dilinde geliştirilmiş WEKA programı ile veri madenciliği yöntemlerinden karar ağacı algoritmaları kullanılmıştır. Oluşturulan karar ağacı algoritmalarından sınıflandırma doğruluğu açısından en başarılı algoritma olarak Random Forest ve ikinci olarak J48 algoritması tespit edilmiştir. Random Forest algoritma çıktısı görsel bir sonuç vermeyip algoritma adımlarını görülmeyecek şekilde vererek karmaşık bir yapı oluşmasından dolayı çalışma J48 algoritmasına göre yorumlanmıştır. Ayrıca, WEKA programında nitelik seçimi özelliği ile InfoGainAttributeEval algoritması ile `Ranker` metodu uygulanması sonucunda çıktıların J48 algoritması çıktıları ile aynı doğrultuda olduğu tespit edilmiştir. Bu bağlamda kabin memurlarının karne düzeylerini en çok etkileyen niteliğin `sürekli öğrenme ve kişisel gelişim` olduğu ve demografik özellikler ile karne düzeyi arasında anlamlı kural olmadığı tespit edilmiştir. Nowadays, the companies are in competition fiercely both for keeping market and catching the developing technology. The fierce competition environment aims to keep current customers and gain new customers. In airline companies, the cabin crew has great affect on providing passengers with services beyond their expectations. Performance evaluations of 3764 cabin crew members were examined in 2015 in an airline company. The levels of scorecard are determined as a result of making these evaluations. The objective of this study is making a meaningful rule between evaluation scores based on competence and demographic features for the levels of scorecard in 2015. In this study, WEKA was used, which is developed in open source code JAVA, and decision tree algorithms which is one of data mining methods. It was explored that Random Forest algorithm was the best algorithm and second one was J48 algorithm in terms of true positive rate in generated decision tree algorithms. This study was interpreted according to the J48 algorithm because Random Forest algorithm output was not suitable for this study due to nonvisual output and complex structure in steps of the algorithm. In addition, it was used for attribute selection with Ranker method in ` Info Gain Attribute Eval` algorithm and the results was detected similar to J48 algorithm outputs. In this regard, it was determined that the most important attribute affecting cabin crew scorecard levels was `Continuous learning and personnel development` and was also determined no meaningful rule between demographic attributes and scorecard level. 101
- Published
- 2019
12. Elektrik dağıtım şirketleri performanslarının analitik hiyerarşi süreci ve veri zarflama analizi ile değerlendirilmesi
- Author
-
Korkmaz, Büşra, Yüksel Özkaya, Banu, and Endüstri Mühendisliği Anabilim Dalı
- Subjects
Analytical hierarchy process ,Data envelopment analysis ,Endüstri ve Endüstri Mühendisliği ,Performance evaluation ,Industrial and Industrial Engineering - Abstract
Türkiye'de elektrik sektörü üretim-iletim-dağıtım olarak 3 ana faaliyetten oluşmaktadır. 2013 yılında elektrik dağıtım sektörü özelleşmesinin tamamlanması sonucunda elektrik dağıtım faaliyeti Türkiye'de 21 bölgede özel dağıtım şirketleri tarafından yapılmaya başlanmıştır. Özelleştirme, rekabet oluşturarak hizmet kalitesini arttırmayı amaçlamaktaydı. Artan rekabet ortamında işletmeler birbirleriyle kıyasıya mücadele etmektedirler ve performans değerlendirme sistemi bu mücadelenin sonuçlarını ortaya koymada önemli bir uygulama olarak görülmektedir. Enerji Piyasası Düzenleme Kurumu elektrik dağıtım şirketlerini periyodik olarak izlemekte ve denetlemektedir. Bunun yanı sıra, Türkiye Elektrik Dağıtım A.Ş.'de elektrik dağıtım şirketlerine periyodik veya kısmi denetimler gerçekleştirmekte ve sonuçlarını Enerji Piyasası Düzenleme Kurumu'na raporlamaktadır. Ancaki tüm faaliyetler için çok kriterli bir yaklaşım kullanılarak dağıtım şirketlerinin performanslarının değerlendirildiği bir performans değerlendirme sistemi bulunmamaktadır. Bu nedenlerle, bu çalışmada elektrik dağıtım sektörüne yönelik detaylı incelemelerde bulunulması, Türkiye'de faaliyet gösteren 21 elektrik dağıtım şirketinin performanslarının değerlendirilmesi için analitik hiyerarşi süreci temelli performans değerlendirme sistemi kurulması ve veri zarflama analiz yaklaşımıyla daha önce yapılan çalışmalar elde edilen yeni verilerle tekrarlanarak bu iki yöntemin sonuçlarının karşılaştırılması amaçlanmıştır. Electricity sector in Turkey has three main activities as generation, tranmission and distribution. After the completion of privalization of electricity distribution sector in 2013, the electricity distribution activities in Turkey. Started to be carried out by private electricity distribution companies in 21 areas. The privatization aimed to increase service quality through competition. Businesses are struggling with each other in an increasingly competitive environment and the performance evaluation systems are considered to be an important practice to demonstrate the results of this struggle. The Energy Market Regulatory Authority monitors and supervises the electricity distribution companies on a periodic basis. In addition, Turkey Electricity Distribution Company Inc. conducts regular or partial audits for electricity distribution companies and reports the results to the Energy Market Regulatory Authority. However, there are no performance evaluation systems where the performance of distribution companies are evaluated using a multiple criteria approach for all activities. Therefore, in this study, it is intended to make a detailed investigation for electricity distribution sector, to establish a performance evaluation system based on analytic hierarchy process for the evaluation of 21 electricity distribution companies in Turkey and to compare the results of the two methods upon the replication of the previous work for data envelopment analysis with recent data. 116
- Published
- 2019
13. Beş Scrophularia L. Türünün Antimikrobiyal Aktivitesi Ve Fenolik Profili
- Author
-
RENDA, Gülin, KORKMAZ, Büşra, YILDIRIM, Sercan, REİS, Ahu, BEKTAŞ, Nurdan Yazici, SEVGİ, Serhat, TÜRKİŞ, Sevda, UZUNHİSARCIKLI, M. Erkan, YAŞAR, Ahmet, and TOSUN, İlknur
- Subjects
Antimikrobiyal aktivite,HPLCDAD,mikrodilüsyon yöntemi,tıbbi bitkiler,Scrophulariatürleri ,Antimicrobial activity,HPLC-DAD,microtiter-plate assay,medicinal plants,Scrophularia species - Abstract
Scrophularia L. genus (Scrophulariaceae) has 310 taxa worldwide. Some Scrophularia species are used in folk medicine for the treatment of different skin inflammatory diseases and as antibacterial. The aim of the study was to investigate the antimicrobial activity and determine the phenolic profile of S. kotscyhana Bentham, S. cinarescens Boiss., S. catariifolia Boiss. & Heldr., S. chrysantha Jaub&Spach and S. scopolii var. adenocalyx Hoppe. ex Pers. Phenolic components were analyzed by an HPLC-DAD method. Disk diffusion method and microtiter-plate assay were used to determine the antimicrobial activities of the aerial parts methanolic extracts of the species. Our results revealed that all of the tested species contain caffeic acid and ferulic acid in varied concentrations and none of them have chlorogenic acid. All of the plant species exhibited moderate activity against Candida albicans (MIC values; 0.3125 mg/mL). Besides, S. cinarescens exhibited moderate activity against Enterococcus faecalis (MIC value; 0.3125 mg/ mL) and S. chrysantha exhibited moderate activity against Pseudomonas aeruginosa (MIC value; 0.3125 mg/mL). The results of this study showed that further studies were needed to identify the secondary metabolites of the species and evaluate their antimicrobial activities., Scrophularia L. cinsi (Scrophulariaceae) dünya üzerinde 310 taksona sahiptir. Bazı Scrophularia türleri halk arasında çeşitli iltihaplı cilt hastalıklarının tedavisinde ve antibakteriyel olarak kullanılır. Çalışmanın amacı, S. kotscyhana Bentham, S. cinarescens Boiss., S. catariifolia Boiss. & Heldr., S. chrysantha Jaub&Spach ve S. scopolii var. adenocalyx Hoppe. ex Pers. türlerinin antimikrobiyal aktivitesini araştırmak ve fenolik profilini belirlemektir. Fenolik bileşenler bir HPLC-DAD yöntemi ile analiz edildi. Türlerin toprak üstü kısımlarının metanol ekstrelerinin antimikrobiyal aktivitelerini belirlemek için disk difüzyon yöntemi ve mikrodilüsyon yöntemi kullanıldı. Bulgularımız, test edilen tüm türlerin, çeşitli konsantrasyonlarda kafeik asit ve ferulik asit içerdiğini ve hiçbirinin klorojenik asit içermediğini ortaya koymuştur. Çalışılan tüm türler, Candida albicans'a (MIC değerleri; 0.3125 mg / mL) karşı orta derecede aktivite göstermiştir. Ayrıca, S. cinarescens, Enterococcus faecalis’e karşı (MIC değeri; 0.3125 mg/mL) ve S. chrysantha Pseudomonas aeruginosa’ya karşı (MIC değeri; 0.3125 mg/mL) orta derecede aktivite gösterdi. Bu çalışmanın sonuçları, türlerin sekonder metabolitlerinin aydınlatılması ve antimikrobiyal etkinliklerinin değerlendirilmesi için daha ileri çalışmalara ihtiyaç duyulduğunu gösterdi.
- Published
- 2018
14. Chemical composition and antimicrobial activity of the essential oils of five Scrophularia L. Species from Turkey
- Author
-
Renda, Gülin, Kalaycı, Yalçın, Korkmaz, Büşra, Karaoğlu, Şengül Alpay, Yaylı, Nurettin, RTEÜ, Fen - Edebiyat Fakültesi, Biyoloji Bölümü, and Karaoğlu, Şengül Alpay
- Subjects
Scrophularia ,SPME GC-FID/MS ,Anti-Tüberküloz Aktivitesi ,Agar Kuyusu Difüzyonu ,Uçucu Organik Bileşikler ,Geleneksel Tıp - Abstract
The essential oils of the five Scrophularia species; Scrophularia chrysantha Jaub. et Spach, Scrophularia kotschyana Benth., Scrophularia olympica Boiss., Scrophularia cinerascens Boiss. and Scrophularia zuvandica Grossh. were obtained by hydrodistillation (HD) with a range of 0.10% to 0.16% yield and analazsed by GC-FID/MS. In the meantime, the volatile organic compounds (VOCs) of S. chrysantha, S. kotschyana, S. olympica, S. cinerascens and S. zuvandica were also identified with the technique of SPME GCFID/MS and the phytochemical results were evaluated. The experimental results of this study showed that the major compounds of essential oils which were taken by the hydrodistillation were carvacrol (52.4%), 2pentadecanone (26.7%), 2-pentadecanone (12.2%), (Z)-2-nonenal (11.2%) and carvacrol (69.1%) respectively. Isovaleraldehyde (37.1%, 27.9%), eucalyptol (13.8%), 2-ethyl furan (14.8%) and 3(Z)-hexenol (91.3%) were respectively found as the main constituents of the five Scrophularia species with SPME method. Also antimicrobial activities of the essential oils of the five Scrophularia species were screened by using agar well diffusion method. It was identified that S. olympica, S.chrysantha, and S. kotschyana, have anti-tuberculosis activity, whereas, the essential oils gained from S. zuvandica and S. cinerascens have anti-fungal activity
- Published
- 2017
15. α-Glucosidase inhibitory effects of polyphenols from Geranium asphodeloides: Inhibition kinetics and mechanistic insights through in vitro and in silico studies
- Author
-
Renda, Gülin, primary, Sari, Suat, additional, Barut, Burak, additional, Šoral, Michal, additional, Liptaj, Tibor, additional, Korkmaz, Büşra, additional, Özel, Arzu, additional, Erik, İshak, additional, and Şöhretoğlu, Didem, additional
- Published
- 2018
- Full Text
- View/download PDF
16. Comparison of phenolic profiles and antioxidant activity of three Ornithogalum L. species
- Author
-
Renda, Gülin, primary, Özel, Arzu, additional, Akyüz Turumtay, Emine, additional, Barut, Burak, additional, Korkmaz, Büşra, additional, Çol Ayvaz, Melek, additional, and Demir, Adem, additional
- Published
- 2018
- Full Text
- View/download PDF
17. The in vitro protection by Crataegus microphylla extracts against oxidative damage and enzyme inhibition effects
- Author
-
Renda, Gülin, primary, Özel, Arzu, additional, Barut, Burak, additional, Korkmaz, Büşra, additional, and Yaylı, Nurettin, additional
- Published
- 2018
- Full Text
- View/download PDF
18. Bioassay Guided Isolation of Active Compounds from Alchemilla barbatiflora Juz.
- Author
-
Renda,, Gülin, primary, Özel, Arzu, additional, Barut, Burak, additional, Korkmaz, Büşra, additional, Šoral, Michal, additional, Kandemir, Ümmühan, additional, and Liptaj, Tibor, additional
- Published
- 2017
- Full Text
- View/download PDF
19. Chemical Composition and Antimicrobial Activity of the Essential Oils of Five Scrophularia L. Species from Turkey
- Author
-
Renda, Gülin, primary, Kalaycı, Yalçın, additional, Korkmaz, Büşra, additional, Alpay Karaoglu, Sengül, additional, and Yaylı, Nurettin, additional
- Published
- 2017
- Full Text
- View/download PDF
20. The Volatile Chemical Compositions of the Essential Oil/SPME and Enzyme Inhibitory and Radical Scavenging Activities of Solvent Extracts and the Essential oils from Coronilla orientalis Miller and C. varia L. grows in Turkey.
- Author
-
Renda, Gülin, Özel, Arzu, Barut, Burak, Korkmaz, Büşra, and Yayli, Nurettin
- Subjects
ESSENTIAL oils ,GLUCOSIDASES ,PHENOL oxidase ,VOLATILE organic compounds ,ENZYMES ,ETHYL acetate ,EXTRACTS - Abstract
The volatile organic compounds (VOCs) of two Coronilla species (Coronilla orientalis Miller and Coronilla varia L.) obtained by hydrodistillation (HD) and solid phase microextraction (SPME) techniques were identified by GC-FID/MS. The major compounds identified in the SPME extracts were limonene (43.4%) in Coronilla orientalis (C. orientalis), (Z)-ß-ocimene and (E)-ß-ocimene (34.3% and 32.4%) in Coronilla varia (C. varia), whereas, the essential oils of C. orientalis and C. varia were rich with γ-terpinene (22.4%) and phytol (30.7%), respectively. In addition, acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), tyrosinase, α-glucosidase enzyme inhibitory, and radical scavenging activities (DPPH) of chloroform, ethyl acetate, methanol, and water extracts, and also essential oils obtained from C. orientalis and C. varia were investigated. The tyrosinase activity was studied at the doses of 25 µg/mL, 50 µg/mL and 100 µg/mL. Tyrosinase inhibition percentage was observed to increase by dose and methanol extracts of the both species were found to have the highest activity. Essential oils of the both species were found to have significant acetylcholinesterase and butyrylcholinesterase inhibition activities. a-Glucosidase enzyme inhibition of the ethyl acetate and water extracts of C. orientalis was determined as 80.11 ± 4.07% and 80.32 ± 3.47% at the 100 µg/mL concentration, respectively. Essential oils, chloroform, ethyl acetate, methanol, and water extracts were determined to have moderate DPPH radical scavenging activities. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
21. Comparison of phenolic profiles and antioxidant activity of three Ornithogalum L. species.
- Author
-
Renda, Gülin, Özel, Arzu, Akyüz Turumtay, Emine, Barut, Burak, Korkmaz, Büşra, Çol Ayvaz, Melek, and Demir, Adem
- Subjects
PLANT phenols ,PHENOLIC acids ,PHENOLS ,OXIDANT status ,ANTIOXIDANTS ,TRADITIONAL medicine ,SPECIES - Abstract
Copyright of Turkish Journal of Biochemistry / Turk Biyokimya Dergisi is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
- Full Text
- View/download PDF
22. In Vitro Protection by Crataegus microphylla Extracts Against Oxidative Damage and Enzyme Inhibition Effects.
- Author
-
RENDA, Gülin, ÖZEL, Arzu, BARUT, Burak, KORKMAZ, Büşra, and YAYLI, Nurettin
- Subjects
TRADITIONAL medicine ,ENZYMES ,ACETYLCHOLINESTERASE ,PHENOL oxidase ,OXIDATIVE stress ,DNA damage - Abstract
Copyright of Turkish Journal of Pharmaceutical Sciences is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
- Full Text
- View/download PDF
23. Comparison of phenolic profiles and antioxidant activity of three OrnithogalumL. species
- Author
-
Renda, Gülin, Özel, Arzu, Akyüz Turumtay, Emine, Barut, Burak, Korkmaz, Büşra, Çol Ayvaz, Melek, and Demir, Adem
- Published
- 2019
- Full Text
- View/download PDF
24. Volatile and Phenolic Contents, Antimicrobial and Tyrosinase activities of Two Endemic Species Scorzonera pisidica and Scorzonera sandrasica L. Grown in Turkey.
- Author
-
Yaylı, Nurettin, Öksüz, Enes, Korkmaz, Büşra, Erik, Ishak, Fandaklı, Seda, Faiz, Özlem, and Coşkunçelebi, Kamil
- Subjects
- *
PHENOL oxidase , *ESSENTIAL oils , *VOLATILE organic compounds , *GALLIC acid , *AROMATIC compounds , *ALDEHYDES - Abstract
Phytochemical analysis of two endemic Scorzonera pisidica Hub.-Mor. and Scorzonera sandrasica Hartvig & Strid species have not been mentioned before. In this work, volatile organic compounds, phenolic contents, antimicrobial, and tyrosinase inhibition activities of two endemic S. pisidica and S. sandrasica grown in Turkey were investigated. Aldehydes were the primary chemical class for the volatile organic compounds in the essential oils (EOs, 49.5%, and 44.9%) and SPME (85.8% and 56.9%) of S. pisidica and S. sandrasica, and aromatic compounds were the main class for the SPME of the n-hexane extracts of S. pisidica (86.9%) and S. sandrasica (86.3%), respectively. The phenolic constituent analysis for the methanol extract of S. pisidica and S. sandrasica gave gallic acid (6.33 mg/g and 2.63 mg/g) as the primary compound. The antimicrobial activity of the EOs and solvent extract (methanol and n-hexane) of S. pisidica and S. sandrasica were tested against nine microorganisms. Furthermore, the inhibitory potential for the methanol extract of the S. pisidica and S. sandrasica showed tyrosinase activity, and IC50 values were found as 0.495±0073 µg/mL and 0.699±0.86 µg/mL, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
25. Chemical Variation, Antimicrobial, Nitric Oxide Scavenging Activities and Tyrosinase Inhibition of Essential Oils and Solvent Extracts from Filipendula vulgaris Moench Growing in Turkey.
- Author
-
Fandakli S, Korkmaz B, Faiz Ö, Kiliç G, Erik İ, Terzioğlu S, and Yaylı N
- Abstract
Volatile organic compositions of the essential oils (EOs), solid-phase microextraction (SPME) and SPME of n -hexane extracts from the flower and stem-leaf of Filipendula vulgaris (F. vulgaris) were analyzed by GC-FID/MS. A total of 107 constituents were characterized, flower and stem-leaf parts of the plant were found to contain different volatile organic compounds. Tricosane (29.6%), n -nonanal (20.5%) were identified as the main components in the essential oil of the flower, while phytol (35.2%) was found to be a major constituent in the essential oil of stem-leaf . Benzaldehyde (56.0%) and n -nonanal (31.6%) were the major groups in the SPME of stem-leaf and flower, respectively. The volatiles for the SPME of n -hexane extracts of the flower and stem-leaf of F. vulgaris were predominated by aromatic compounds (75.0% and 78.5%) and ketones (18.1% and 10.1%), respectively. On the other hand, a total of terpene compounds was found at the most in the EO of the stem-leaf part of the plant (48.6%). In addition, antimicrobial, tyrosinase inhibition, and nitric oxide scavenging activities of the n -hexane (H), methanol (M), aqueous extracts (A) and EOs of F. vulgaris were investigated. EOs and methanol extracts of flower and stem-leaf had high antimicrobial activity against tested various microorganisms . However, n -hexane extracts of the flower and stem-leaf only displayed activity against Mycobacterium smegmatis . Methanol extracts of flower and stem-leaf possessed the best tyrosine inhibition and NO scavenging activity.
- Published
- 2021
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.