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Graph Theory Based Traffic Light Management
Master Thesis
403
Recent Submitted Publications
Escherichia Coli Konak Organizmada GLP-1 Analoğunun Rekombinant Üretimi
(Abdullah Gül Üniversitesi, Fen Bilimleri Enstitüsü, 2024) Çalış, Burak; Fidan, Özkan
Diabetes is the most serious metabolic disorder correlated with obesity, hypertension and cardiovascular conditions. High prevalence of Type II Diabetes Mellitus (T2DM) indicates the need for new medication development. In developing therapeutics, higher efficiency and fewer adverse effect features are targeted primarily. Recombinant protein-based biotechnological drug molecules have been developed and used for the treatment of T2DM. Especially, GLP-1 analogues are known by their self-limiting mechanism and insulinotropic effect. In this study, a novel GLP-1 analogue with increased stability and efficiency is produced using recombinant E. coli. The expression plasmid was constructed and confirmed by restriction digestion and whole plasmid sequencing. Then, itwas transformed into various E. coli strains followed by optimized lysis, growth and expression conditions to maximize the yield of the GLP-1 analogue. Various parameters such as pre-induction time, induction point, induction IPTG concentration and post-induction temperature were tested for the succesfull expression with maximum yield. Consequently, it was achieved that E. coli BL21(DE3) as strain, 0.2 mM IPTG induction at OD600nm of 0.6 and 18 °C overnight post-induction growth was the most promising conditions. Under these conditions, the GLP-1 analogue was obtained in the insoluble fraction. Following protein analysis and purification, quantification was performed and the highest titer of GLP-1 analogue was measured as 626 µg/ml. As future prospect, using another host organism and changing growth conditions can provide obtaining target protein in the soluble form. Keywords: T2DM, GLP-1 analogue, recombinant DNA technology, protein expression, E. coli
Agency Theory: A Review in Finance
(2020) Polat, Ali Yavuz; Tekin, Hasan
Temsil ve risk paylaşımı problemleri büyük firmalarda sahiplik ve kontrolün ayrılmış olmasından dolayı, müvekkil (sahipler) ve vekil (yöneticiler) arasında çıkar çatışması olduğunda ortaya çıkmaktadır. Bu problemler temel olarak bilgi asimetrisinden kaynaklanmaktadır. Bu da müvekkil için vekalet maliyeti ortaya çıkarmaktadır. Halihazırdaki önemli teorilerden biri olan Vekil Teorisi vekalet ilişkilerindeki maliyetleri minimize etmeye odaklanmaktadır. Bu çalışma müvekkil-vekil ilişkilerini daha iyi anlamak için, kurumsal finans alanındaki hissedar-yönetici ve tahvil sahibi-hissedar ilişkilerine odaklanarak, müvekkil-vekil ilişkilerini kritik bir şekilde değerlendirmektedir.
Citation - WoS: 6
Citation - Scopus: 5
Amorphous Boron Carbide From Ab Initio Simulations
(Elsevier, 2020) Yildiz, Tevhide Ayca; Durandurdu, Murat
An amorphous boron carbide (a-B4C) model is generated by means of ab-initio molecular dynamics calculations within a generalized gradient approximation and its structural, mechanical and electrical features are discussed in details. The mean coordination number of B and C atoms is estimated to be 5.29 and 4.17, respectively. The pentagonal pyramid-like motifs for B atoms, having sixfold coordination, are the main building units in a-B4C and some of which involve with the development of B-12 icosahedra. On the other hand, the fourfold-coordinated units are the leading configurations for C atoms. Surprisingly the formation of C-C bonds is found to be less favorable in the noncrystalline network, compared to the crystal. a-B4C is a semiconducting material having an energy band gap considerably less than that of the crystal. A noticeably decrease in the mechanical properties of B4C is observed by amorphization. Nonetheless a-B4C is categorized as a hard material due to its high Vickers hardness of about 24 GPa.
Citation - WoS: 13
Citation - Scopus: 12
Organic and Inorganic Semiconducting Materials-Based SERS: Recent Developments and Future Prospects
(Royal Soc Chemistry, 2024) Ozdemir, Resul; Ozkan Hukum, Kubra; Usta, Hakan; Demirel, Gokhan
Surface-enhanced Raman spectroscopy (SERS) with high sensitivity/selectivity is a powerful analytical tool and has been widely used, particularly in the fields of chemistry, spectroscopy, molecular detection, food safety, anti-counterfeiting, and environmental monitoring. Conventional SERS detection relies on plasmonic materials (e.g., Au and Ag nanostructures) with exceedingly high enhancement factors up to 1012. However, these substrates encounter significant limitations, including poor reproducibility, high cost, lack of selectivity, limited SERS active area leading to inconsistent field enhancement and SERS signals, and the possibility of the photothermal decomposition of the analyte species. These drawbacks have the potential to impede detection accuracy and hinder large-scale practical applications. This review focuses on alternative approaches based on noble metal-free SERS substrates. Considering recent advancements in the field of SERS active platforms, we first introduce the implementation of inorganic compounds, including metal oxides, transition metal sulfides/-selenides/-tellurides, 2-D layered transition metal carbides and nitrides (Mxenes), metal-organic frameworks (MOFs), and single elemental inorganic materials for Raman signal enhancement applications. In the second part of the review, we highlight the fast-growing field of SERS-active organic platforms. Moreover, we discuss the promises and challenges for the future direction of organic and inorganic material-based SERS. Surface-enhanced Raman spectroscopy (SERS) is a powerful analytical tool and has been widely used, in different fields including molecular detection, food safety, anti-counterfeiting, and environmental monitoring.
Editoryal: Grup Dinamikleri Bağlamında Çatışma Çözümü ve Barış İnşası
(Türk Psikoloji Dergisi, 2020) Çoymak, Ahmet; Uluğ, Özden Melis; Göregenli, Melek; Çakal, Hüseyin
Çatışmanın insanın doğası olduğuna yönelik teorilerin (örn. Berkowitz, 1990; Fiske, 2012) adeta toplumsal tezahürü gibi, geçtiğimiz yüzyıldan günümüze dünya birçok kanlı çatışmaya sahne oldu. Devam eden uluslararası kanlı savaşların yanı sıra, ortaya çıktığı 19. yüzyıldan bugüne farklılıkları bir milli kimlik potasında eritmeyi amaçlayan ulus devletlerde etnik, dini, mezhep ve cinsiyet grupları gibi farklı vatandaş grupları arasında; sonu, kimi zaman insanlığın en karanlık yüzünü gösteren soykırımlara varan çatışmalar yaşandı. Ancak bu acı deneyimlerin yanında insan ve farklı özellikleri olan gruplar, yine hem uzlaşı hem de barış süreçlerinden geçtiler. Bu nedenle, insanın kendi türüne karşı işlediği suçların (örn. Staub, 2001), biz ve öteki inşası ile yaşanan çatışmaların (Demirdağ ve Hasta, 2020; Fisher, 2006); bu deneyimlerin ortaya çıkardığı uzlaşı ve ortaklıkların psikolojik dinamiklerini, hem çok çeşitli ve zengin kuramsal perspektifler hem de ampirik bulgularla, gruplar arası ilişkilere odaklanarak anlamayı amaçladık.