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    Basel II Kriterlerinin Reel Sektöre Etkileri ve Basel III Kriterlerinin Bankalar Üzerine Etkilerinin Araştırılması
    (Selçuk Üniversitesi, 2019) Doğan, Ahmet; İlleez, Hatice
    Çalışmanın amacı, Basel II Kriterlerinin ülkemizdeki reel sektöre muhtemel etkileri ile Basel III Kriterlerinin bankalar üzerindeki etkilerini araştırmaktır. İstanbul Sanayi Odası’nın yayınladığı ilk 1000 firma arasındaki Kayseri’deki 30 firmanın soru formu ve birebir görüşme yoluyla 17’sinden elde edilen veriler SPSS programı kullanılarak değerlendirilmiştir. Reel sektörün Basel II’ye bakış açısı konusunda firmaların Basel II’den beklentilerinin, kısa vadede %82,4’ünün olumlu, Orta ve uzun vadede ise bütün firmaların olumlu beklentileri olduğu sonucuna ulaşılmıştır. Basel II Kriterlerinde risk yönetimi önemli bir konudur. Firmaların %23,5’i risk yönetimi bölümünün olduğunu, %76,5’i risk yönetimi bölümünün olmadığını belirtmiştir. Bankacılık sektörünün Basel III Kriterlerinden Sermaye Yeterlilik Oranı, Likidite ve Kârlılık oranları konularında etkilendiği belirlenmiştir. Türkiye’de faaliyet gösteren aktif büyüklüğü sıralamasındaki ilk beş bankanın finansal tablolarından yararlanılarak analizler yapılmıştır. Analizler sonucunda Basel III’ün oran kriterlerine bankaların uyumlu olduğu ve sektör ortalamalarının genellikle üzerinde oldukları tespit edilmiştir. Bu bankaların Basel III’e hazır oldukları görülmüştür.
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    Bioactivities of Achillea phrygia and Bupleurum croceum based on the composition of phenolic compounds: In vitro and in silico approaches
    (PERGAMON-ELSEVIER SCIENCE LTD, 2017) Zengin, Gökhan; Bulut, Gizem; Mollica, Adriano; Haznedaroğlu, Mehmet Zeki; Doğan, Ahmet; Aktümsek, Abdurrahman
    This study presents the effects of the Achillea phrygia Boiss. et Bal. and Bupleurum croceum Fenzl. extracts obtained by different solvents (ethyl acetate, methanol and water) on selected enzyme inhibitory effects and antioxidant ability with screening bioactive compounds. Total and individual bioactive compounds were detected by spectrophotometric and HPLC-DAD techniques. Antioxidant abilities were evaluated by different methods including free radical scavenging (ABTS and DPPH), reducing power (CUPRAC and FRAP), phosphomolybdenum and metal chelating. Enzyme inhibitory effects were tested against cholinesterases, tyrosinase, amylase, glucosidase and lipase. Total phenolic contents were ranged from 20.52 mgGAE/g extract (B. croceum methanol extract) to 41.13 mgGAE/g extract (A. phrygia methanol extract). Generally, methanol and water extracts showed the strongest antioxidant abilities, while the ethyl acetate extracts had the most promising enzyme inhibitory effects. HPLC analysis revealed the abundance of some phenolics including rutin, quercetin, sinapic acid and chlorogenic acid, respectively. These components were also assessed using molecular modelling with the aim to study their docking properties on a set of six enzymes used in this study. Overall, these species could be suggested as valuable sources of natural-bioactive agents for developing new functional, pharmacological and health promoting ingredients. (C) 2017 Elsevier Ltd. All rights reserved.
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    Genel liselerde okutulan trigonometri konularının öğretiminde öğrencilerin yanılgıları, yanlışları ve trigonometri konularına karşı öğrenci tutumları üzerine bir araştırma
    (Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2001-09-12) Doğan, Ahmet; Şenay, Hasan
    Bu araştırmada; Genel Liselerde okutulan trigonometri konuları hakkında öğrencilerin düşünceleri ve trigonometri konularının işlenişi ile ilgili olarak öğrencilerin görüşleri alındı. Trigonometri konuların da hangi yanılgılara sahip oldukları ve alınması gereken tedbirlerin neler olacağı sorularına cevap arandı. Araştırmada Konya İli Evren olarak seçildi. Konya'nın kazaları sosyo-ekonomik seviyelerine göre A, B, C olmak üzere üç gruba ayrıldı. İlçe merkezlerindeki genel liselerin 2. sınıf öğrencilerinden toplam 1316 öğrenciye; araştırmacı tarafından çoktan seçmeli olarak geliştirilmiş olan, "Trigonometri Düşünceler Anketi (B-l), Trigonometri Bilgi Formu (B-2) ve Trigonometri Teşhis Testi (B-3)" olmak üzere üç ayn test uygulandı. Elde edilen veriler değerlendirildi. Öğrencilerin %21,89'unun trigonometri konularını sevdiği, % 45,52 oranında öğrencinin de trigonometri konularını sevmediği tespit edildi. "Trigonometrinin adını bile duymak istemem" diyen öğrenciler % 30,93 oranındadır. "Elimde olsa trigonometri okumazdım diyen öğrencilerin oram % 46,43 'tür. Öğrencilerin; trigonometri konularını mecbur oldukları için oku dukları, hayatta bir işlerine yaramayacağı, okutulmasının bile anlamsız olduğu gibi kaygı verici saplantı lar içinde oldukları görüldü. % 51,75 oranında öğrenci derslerin işlenişinde, konu ile ilgili materyallerin kullanılmadığını belirtmiştir. ÖSS.de trigonometriden soru sorulmayışınm, trigonometri konularını öğ renme isteğini azalttığını belirten öğrenciler % 65,35 oranındadır. Öğrencilerin toplam % 65,96'sı, seviye gruplarında öğrenmenin daha kolay olduğu düşüncesindedir. öğrencilerin trigonometrik kavramları karıştırdıkları, trigonometrik denklemlerin çözümünde, öz deşliklerin kullanılmasında, birim çemberin kullanılmasında, trigonometrik fonksiyon değeri ile açmm ölçüsünü ayırmada ciddi güçlükler içinde oldukları tespit edildi, özellikle sadeleştirme işlemlerinde, sayılarla ilgili yanılgılarından kaynaklanan yanlışlar yaptıkları görüldü. Geometrik şekillere dayalı trigo nometri sorularında öğrencilerin başarısız oldukları, formüllere uygulayabilecekleri sorulan daha kolay yaptıkları tespit edildi.
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    HPLC-MS/MS-based metabolic profiling and pharmacological properties of extracts and infusion obtained from Amelanchier parviflora var. dentata
    (ELSEVIER SCIENCE BV, 2018) Zengin, Gökhan; Diuzheva, Alina; Jeko, Jozsef; Cziaky, Zoltan; Bulut, Gizem; Doğan, Ahmet; Haznedaroğlu, Mehmet Zeki
    Arnelanchierparviflora var. dentata is an endemic medicinal plant traditionally consumed to treat stomach pain, cardiovascular diseases, and urinary tract infections in Turkey's folk medicine. Although Amelanchier genus is an excellent source of phytochemicals with a panoply of biological activities, no report has been made available on Amelanchier parviflora var. dentata. Thus, the metabolic profiles of methanol, ethyl acetate, and water extracts were obtained using HPLC-MS/MS. Besides, the pharmacological properties such as antioxidant activity and enzyme inhibition effects against acetyl/butyrylcholinesterase, tyrosinase, alpha-amylase, and alpha-glucosidase were evaluated. In total, 62, 38, and 16 metabolites were Identified from the methanolic, water, and ethyl acetate extracts, respectively. The identified metabolites belong to anthocyanins, phenolic acids, and flavonoids. The tested extracts exhibited different enzyme inhibitory activity against cholinesterases (acetylcholinesterase: 0.52-2.47 mg GEs/g extract and butyrylcholinesterase: 0.47-3.59 mg GEs/g extract), tyrosinase (19,0-145.54 mg KAEs/g extract), alpha-amylase (0.23-1.10 mmol ACEs/g extract), and alpha-glucosidase (8.89-9.92 mmol ACEs/ g extract). Evidence from the present study supports the necessity for more research in an endeavor to discover biologically active secondary metabolites from A. parviflora to manage specific ailments.
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    Influence of different extraction techniques on the chemical profile and biological properties of Anthemis cotula L.: Multifunctional aspects for potential pharmaceutical applications
    (ELSEVIER SCIENCE BV, 2019) Sut, Stefania; Dall'Acqua, Stefano; Zengin, Gökhan; Şenkardeş, İsmail; Bulut, Gizem; Cvetanovic, Aleksandra; Stupar, Alena; Mandić, Anamarija; Picot-Allain, Carene; Doğan, Ahmet; Sinan, Kouadio Ibrahime; Mahomoodally, Fawzi
    The phytochemical composition of different extracts obtained from stinking chamomile (Anthemis cotula L) was investigated. Ethanol was used as solvent and accelerated solvent extraction (ASE), microwave assisted extraction (MAE), maceration, soxhlet extraction (SE), and ultrasound assisted extraction (UAE) were applied on plant material. Comparison of the phytochemical contents, antioxidant, and enzyme inhibitory properties were performed. The most abundant sesquiterpene in the extracts was anthecotuloide, while the most present phenolics were caffeoyl quinic acid, quercetin, and kaempferol derivatives. UAE extract was the most efficient in the extraction of sesquiterpenoids and polyphenols. Considering the assays on antioxidant activity and enzyme inhibition, ASE extract showed highest phenolic content (62.92 mg gallic acid equivalent/g extract). Likewise, this extract showed highest radical scavenging (103.44 mg trolox equivalent [TE]/g extract and 155.70 mg TE/g extract, for DPPH and ABTS assays respectively) and reducing power potential (435.32 and 317.89 mg TE/g extract, for CUPRAC and FRAP assays, respectively). The different extracts showed similar results in the enzyme inhibition assays suggesting that the extraction methods used have no effect on observed enzyme activities. Novelty of our findings are the inhibitory action of the ethanol extract of A. cotula aerial parts on key enzymes associated with Alzheimer's disease (acetyl cholinesterase, butyryl cholinesterase), type 2 diabetes (alpha-amylase, alpha-glucosidase), and skin hyperpigmentation disorders (tyrosinase). Data collected from the present work further appraises the multiple potential biological properties of stinking chamomile suggesting the need for further investigation on its constituents. (C) 2019 Elsevier B.V. All rights reserved.
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    New insights into the in vitro biological effects, in silico docking and chemical profile of clary sage - Salvia sclarea L.
    (ELSEVIER SCI LTD, 2018) Zengin, Gökhan; Şenkardeş, İsmail; Mollica, Adriano; Picot-Allain, Carene Marie Nancy; Bulut, Gizem; Doğan, Ahmet; Mahomoodally, M. Fawzi
    Salvia sclarea L. is traditionally used to manage common human ailments and is consumed as a food product. This study aimed to establish the phytochemical profile and antioxidant potential of ethyl acetate, methanol, and water extracts of Salvia sclarea. The inhibitory action of the extracts against alpha-amylase, alpha-glucosidase, acetyicholinesterase, butyrylcholinesterase, and tyrosinase was also investigated. Methanol extract showed the highest phenolic and fiavonoid contents (81.78 mg GAE/g extract and 40.59 mg RE/g extract, respectively). Reversed phase high performance liquid chromatography with diode array detector analysis revealed that S. sclarea was rich in rosmarinic acid. The water extract exhibited the lowest inhibitory activity against alpha-amylase but the upmost activity against alpha-glucosidase (0.19 and 18.24 mmol ACAE/g extract, respectively). Experimental data showed that only the water extract (8.86 mg KAE/g extract) significantly inhibited tyrosinase. Docking studies showed that quercetin binds to tyrosinase by two hydrogen and a pi-pi bonds. Salvia sclarea showed interesting biological activity against key enzymes involved in the pathogenesis of common ailments. (C) 2018 Elsevier Ltd. All rights reserved.
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    Paeonia arietina and Paeonia kesrounansis bioactive constituents: NMR, LC-DAD-MS fingerprinting and in vitro assays
    (ELSEVIER SCIENCE BV, 2019) Sut, Stefania; Zengin, Gökhan; Dall'Acqua, Stefano; Gazdova, Marketa; Smejkal, Karel; Bulut, Gizem; Doğan, Ahmet; Haznedaroğlu, Mehmet Zeki; Aumeeruddy, Muhammad Zakariyyah; Maggi, Filippo; Mahomoodally, Mohamad Fawzi
    Paeonia species have been valued for their ethnomedicinal uses in various countries and received much interest among the scientific community for their therapeutic properties, including anti-microbial, anti-inflammatory, anti-cancer, nephroprotective and hepatoprotective effects. The multiple phytother-apeutical applications of Paeonia species inspired us to establish the phytochemical fingerprint and to evaluate the biological properties of ethyl acetate, methanol, and aqueous extracts from the roots and aerial parts of two Paeonia species (P. arietina G. Anderson and P. kesrounansis Thiebaut). Phytoconstituents of P. arietina and P. kesrounansis extracts were analyzed using 1D and 2D NMR and LC-DAD-ESI-MS. The total content of phenolics (TPC) and flavonoids (TFC) in the extracts was also evaluated. The antioxidant activity was profiled using DPPH, ABTS, CUPRAC, FRAP, phosphomolybdenum, and metal chelation assays. Enzyme inhibitory properties were evaluated against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, alpha-amylase, and alpha-glucosidase. Phytochemical analysis of P. arietina and P. kesrounansis extracts showed the presence of galloyl esters of sugars, galloyl monoterpenes, and glycosylated flavonoids. The three solvent extracts presented different behavior in the bioassays. The highest antioxidant activity, tyrosinase and AChE inhibition were observed for the methanolic extract of the aerial parts of P. kesrounansis. In addition, the ethyl acetate extracts of the aerial parts of both plants were the most effective inhibitors of alpha-amylase. The highest BChE inhibition was observed for root methanolic extract of P. kesrounansis while the root ethyl acetate extract of P. arietina exerted the strongest inhibition of alpha-glucosidase. Methanol extract of P. kesrounansis aerial parts presented the highest TPC, while TFC was greatest in the corresponding extract of P. arietina. Our findings can be considered as a starting point for future studies to further validate the effectiveness and safety profiles of these plants in folk medicine. (C) 2018 Elsevier B.V. All rights reserved.