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Acoustic Transformation of Rock-Cut Caves Into Performance Spaces
(European Acoustics Association, EAA, 2023) Aslan, Ahmet; Şaher, Konca; Tozoğlu, Ahmet Erdem
Cappadocia Region in Turkey is a center of attention as a tourism destination with its rock-cut caves, some of which are being used as performance spaces for concerts, festivals and local entertainment activities. However, these spaces are not fully investigated for their acoustic performance before being transformed into performance venues. This paper reports on the findings of an initial survey which presents a systematic mapping of the rock-cut caves used as performance spaces to locate, explore and document a sample of structures scattered in this historic district. A typological classification based on volume, size, type of tuff rock material and historical original use has been proposed and an acoustic analysis of some selected rock-cut caves has been carried out. The acoustic analysis included reverberation time calculations and simulations based on apparent volume, and tuff stone absorption characteristics, which were studied by other researchers in the area. © 2024 Elsevier B.V., All rights reserved.
Active Control of the Nanoparticle Self-Assembly for Photonic Applications
(META Conference, 2023) Erdem, Talha
Colloidal nanoparticles enable collective utilization of the inherent properties of the nanoparticles. Furthermore, their collective optical response can be fine-tuned employing DNA-driven self-assembly. Here, we present that the optical transmission of self-assembled DNA-functionalized gold nanoparticle network can be actively manipulated using an external optical excitation. We also show control of optical polarization of emitted light from semiconducting supraparticle networks hybridized with magnetic supraparticles. These results prove the potential of programmed nanoparticle self-assembly in tailoring optical features of colloidal systems. © 2023 Elsevier B.V., All rights reserved.
Citation - Scopus: 1
AlN Piezoelectric Quad-Actuators for 2D Optical Micro Scanning
(Taylor & Francis Ltd, 2022) Hah, Dooyoung
Piezoelectric actuation has been one of the frequent choices for optical micro scanning. In most of the cases, lead zirconate titanate (PZT) has been used as the piezoelectric material. However, PZT has a potential issue in biomedical applications due to the content of lead. For this, AlN can be used as an alternative. The main drawback of AlN is its low piezoelectric coefficients. In order to overcome such a drawback, this paper presents a novel actuator configuration, designed for a quasi-static operation mode. Quad-actuators and meander-shaped hinges are the essence of the proposed actuator configuration. Numerical simulation study is carried out to prove the concept of the device. The study also shows that the proposed scanner can have the optical scan angle of 9 degree at a quasi-static mode. Two different scan modes, a raster-like mode and a Lissajous mode are tested, demonstrating the two-dimensional scanning capability of the device.
Citation - WoS: 2
Citation - Scopus: 2
Analysis of the Motion of a Rigid Rod on a Circular Surface Using Interpolated Variational Iteration Method
(Yildiz Technical Univ, 2022) Coskun, Safa Bozkurt; Senturk, Erman; Atay, Mehmet Tarik
In this paper, interpolated variational iteration method (IVIM) is applied to investigate the vibration period and steady-state response for the motion of rigid rod rocking back and forth on a circular surface without slipping. The problem can be considered as a strongly nonlinear oscillator. In this solution procedure, analytical variational iteration technique is utilized by evaluating the integrals numerically. The approximate analytical results produced by the presented method are compared with the other existing solutions available in the literature. The advantage of using numerical evaluation of integrals, the method becomes fast convergent and a highly accurate solution can be obtained within seconds. The authors believe that the presented technique has potentially wide application in the other nonlinear oscillation problems.
Citation - Scopus: 7
ANT-M: Design of Passive Lower-Limb Exoskeleton for Weight-Bearing Assistance in Industry
(Springer International Publishing, 2019) Guncan, Berkay; Unal, Ramazan
This study describes the optimized design of a passive lower limb exoskeleton for workers in the industry. The exoskeleton is aimed at helping workers who carry heavy loads, by supporting their posture and reducing stress in their knees which would prevent future injuries. However, most of the previous passive designs are insufficient in a way that they are bulky. Therefore, this study is focused on achieving lightweight passive exoskeleton. Topology optimization has been carried out to reach this goal. The results are validated using finite elements methods, in ANSYS environment. © 2018 Elsevier B.V., All rights reserved.
Anticancer Effect of Ethanolic Yellow Hawthorn Extract on Chronic Myeloid Leukemia Cells and Acute Myeloid Leukemia Cells
(Ondokuz Mayis Universitesi, 2025) Arslan, Ayşe Nur; Akçok, Ismail
Cancer is a disease characterized by abnormal cell growth and invasion and metastasis of these cells to other tissues or organs of the body. Natural products have been used for centuries as drugs or in drug development, especially for the treatment of cancer. Besides, extracting natural products with several bioactive compounds has a promising effect on cancer treatment. In this study, we aimed to investigate the anticancer effect of the ethanolic extract of yellow hawthorn fruits on K562 (Chronic Myeloid Leukemia) and MOLM-13 (Acute Myeloid Leukemia) cell lines. The antiproliferative effect of the ethanolic extract of yellow hawthorn fruits was investigated in time-and dose-dependent manners. The Annexin-V/Propidium Iodide (PI) double staining was used to examine the apoptosis. Furthermore, cell cycle analysis is conducted by PI staining. The cell viability of K562 and MOLM-13 cell lines was significantly reduced by the ethanolic extract of yellow hawthorn fruits with IC50 values of 9144 µg/mL and 3515 µg/mL in 48-hour incubation time, respectively. Moreover, the results showed that the ethanolic extract of yellow hawthorn fruits caused an increased apoptosis by 12.7-and 8.87-fold changes in K562 and MOLM-13 cell lines compared to control groups, respectively. Ethanolic extract of yellow hawthorn fruit has reduced cell proliferation, induced apoptosis and arrested the cell cycle at G0/G1 phase by 71% in MOLM-13 and at G2/M phase by 80.3% and G0/G1 phase by 38.2 % in K562 cells. Further studies should be conducted to elucidate the mechanism of the effect of yellow hawthorn fruit on these cancer cells. © 2025 Elsevier B.V., All rights reserved.
Apatinib Sensitizes Human Breast Cancer Cells Against Navitoclax and Venetoclax Despite Up-Regulated Bcl-2 and Mcl-1 Gene Expressions
(Kare Publ, 2021) Kavakcioglu Yardimci, Berna; Ozgun Acar, Ozden; Semiz, Asli; Sen, Alaattin; Acar, Ozden Ozgun; Yardımcı, Berna Kavakcıoğlu
OBJECTIVE Defects in apoptotic cell death which restrict the success of conventional cytotoxic therapies have pivotal roles in a number of pathological conditions including cancer. However, a novel drug class targeting pro-survival Bcl-2 protein family members has been developed with the understanding of the structures and interactions of Bcl-2 proteins. Within this new class, Bcl-2/Bcl-xL inhibitor Navitoclax and Bcl-2 specific inhibitor Venetoclax have been shown to demonstrate strong anticancer activities on several types of cancers. But their low affinity to other anti-apoptotic proteins limits their clinical usage. Here, we investigated the cytotoxic and apoptotic effects of Navitoclax/Venetoclax and their combinations with specific tyrosine kinase inhibitor Apatinib on estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 breast cancer cell lines. METHODS MTT assay was used for the evaluation of the inhibition of cancer cell proliferation. ELISA test and Quantitative real-time PCR assay was performed to determine the role of caspase-3, Bak, Bax, Bcl-2, Bcl-xL and Mcl-1 proteins in the inhibition of cell proliferation triggered by the tested agents. RESULTS We found that aggressive MDA-MB-231 cell line was more sensitive to all tested agents. Apatinib significantly enhanced Navitoclax/Venetoclax mediated inhibition of cell viability in both cancer cell lines despite up-regulation in the expression levels of Bcl-2 and Mcl-1 genes. We further demonstrated significant Bak/Bax and caspase-3 expression in less aggressive MCF-7 cells. CONCLUSION Our findings have impacts on Navitoclax/Venetoclax plus Apatinib based therapy for breast adenocarcinoma. On the other hand, further studies should be conducted to elucidate the mechanisms underlying synergistic effects of Navitoclax/Venetoclax plus Apatinib combinations.
Citation - WoS: 3
Citation - Scopus: 3
Artificial Cells: A Potentially Groundbreaking Field of Research and Therapy
(Sciendo, 2024) Dundar, Mehmet Sait; Yildirim, A. Baki; Yildirim, Duygu T.; Akalin, Hilal; Dundar, Munis
Artificial cells are synthetic constructs that mimic the architecture and functions of biological cells. Artificial cells are designed to replicate the fundamental principles of biological systems while also have the ability to exhibit novel features and functionalities that have not been achieved before. Mainly, Artificial cells are made up of a basic structure like a cell membrane, nucleus, cytoplasm and cellular organelles. Nanotechnology has been used to make substances that possess accurate performance in these structures. There are many roles that artificial cells can play such as drug delivery, bio-sensors, medical applications and energy storage. An additional prominent facet of this technology is interaction with biological systems. The possibility of synthetic cells being compatible with living organisms opens up the potential for interfering with specific biological activities. This element is one of the key areas of research in medicine, aimed at developing novel therapies and comprehending life processes. Nevertheless, artificial cell technology is not exempt from ethical and safety concerns. The interplay between these structures and biological systems may give rise to questions regarding their controllability and safety. Hence, the pursuit of artificial cell research seeks to reconcile ethical and safety concerns with the potential advantages of this technology.
Atatürk’ün Esir Aldığı Yunan General Nikolaos Trikupis ve Talas Üsera Garnizonu
(Sabit Dokuyan, 2023) Karataş, Murat; Metin, Mehmet
After the First World War, especially with the support of England, the Greek army invaded Anatolian lands on the way to realize Megali Idea (Greater Greece). The regular army of the Turkish Grand National Assembly established on the Western Front dealt the final blow to the Greek army with The Great Offensive and the Battle of the Commander –in-Chief. In addition to the Greek soldiers captured in the wars before this victory, many Greek soldiers, as well as the commander –in-chief of the Greek army, General Trikupis, and her entourage were also captured after the said victory. As the number of prisoners increased rapidly after The Great Offensive and the Battle of the Commander –in-Chief, the captive officers were transferred to Afyon, Kırşehir and Kayseri. Other military and civilian prisoners were transferred to different parts of Anatolia. Greek prisoners of war were kept in the prisoner garrisons until the implementation of the document on the mutual release of prisoners signed between the states of Turkey and Greece at the Lausanne Peace Conference. Only Greek Officers remained in Talas Prisoner Garrison, one of these prisoner garrisons. The Talas Prisoner Garrison was inspected twice by international Committee of the Red Cross. The delegation prepared reports on the condition of the prisoners and the garrison. In this study, the captivity of General Trikupis on the battlefield, the Talas Prisoner Garrison and situation of the captive Greek officers staying here, the aid of the Red Crescent Society to the prisoners will be emphasized. The Study was planned to be prepared by making use archival resources, memoirs, newspapers and copyright-reviewed works. © 2023 Elsevier B.V., All rights reserved.
Bazı geleneksel Türk gıdalarından laktik asit bakterilerinin izolasyonu
(2021) DOĞAN Osman; CEBECİ Aysun
Amaç: Bu çalışma ülkemizde geleneksel yöntemlerle üretilen gıda ürünlerindenlaktik asit bakterilerinin izolasyonunu ve tanımlanmasını sağlamak amacıylayapılmıştır.Materyal ve Yöntem: Çalışma kapsamında Van otlu peynir ve ekşi hamur örneğikullanılmıştır. Bu örnekler içerdikleri laktik asit bakterileri için çalışılmış vetanımlanmaları için biyokimyasal ve PCR bazlı moleküler biyolojik tekniklere tabitutulmuşlardır. Biyokimyasal testler kapsamında örnekler, Gram reaksiyonları,katalaz aktivitesi, gaz üretimi, 10oC ve 45oC'de, %6 ve %16 NaCl konsantrasyonda,pH 4.4 ve pH 9.6’da gelişim göstermeleri açısından incelenmiştir. Moleküler biyolojideneyleri kapsamında ise tür ve suş düzeyinde tanımlama için PCR-RFLP, 16SrRNA gen dizileme ve RAPD-PCR teknikleri kullanılmıştır.Araştırma Bulguları: Bir dizi mikrobiyolojik deneylerin sonucunda 26 adet bakteripotansiyel laktik asit bakterisi olarak izole edilmiştir. Bunlardan 25 adedininLactobacillus, Pediococcus ve Enterococcus cinslerine ait olduğu tespit edilmiş vetür ve suş düzeyinde tanımlanmaları sağlanmıştır. Kalan bir adet izolat iseStaphylococcus hominis olarak tanımlanmıştır.Sonuç: Çalışmamız sonucunda 25 adet laktik asit bakterisi gen dizileme ve RAPDPCR teknikleri kullanılarak tür ve suş düzeyinde başarıyla tanımlanmıştır.
Citation - WoS: 1
Citation - Scopus: 3
Biosynthesis of Novel Naphthoquinone Derivatives in the Commonly-Used Chassis Cells Saccharomyces Cerevisiae and Escherichia Coli
(Pleiades Publishing inc, 2021) Wu, W.; Wang, S.; Zhang, H.; Guo, W.; Lu, H.; Xu, H.; Sun, L.
Naphthoquinones harboring 1,4-naphthoquinone pharmacophore are considered as privileged structures in medicinal chemistry. In pharmaceutical industry and fundamental research, polyketide naphthoquinones were widely produced by heterologous expression of polyketide synthases in microbial chassis cells, such as Saccharomyces cerevisiae and Escherichia coli. Nevertheless, these cell factories still remain, to a great degree, black boxes that often exceed engineers' expectations. In this work, the biotransformation of juglone or 1,4-naphthoquinone was conducted to generate novel derivatives and it was revealed that these two naphthoquinones can indeed be modified by the chassis cells. Seventeen derivatives, including 6 novel compounds, were isolated and their structural characterizations indicated the attachment of certain metabolites of chassis cells to naphthoquinones. Some of these biosynthesized derivatives were reported as potent antimicrobial agents with reduced cytotoxic activities. Additionally, molecular docking as simple and quick in silico approach was performed to screen the biosynthesized compounds for their potential antiviral activity. It was found that compound 11 and 17 showed the most promising binding affinities against Nsp9 of SARS-CoV-2, demonstrating their potential antiviral activities. Overall, this work provides a new approach to generate novel molecules in the commonly used chassis cells, which would expand the chemical diversity for the drug development pipeline. It also reveals a novel insight into the potential of the catalytic power of the most widely used chassis cells.
Citation - WoS: 12
Citation - Scopus: 15
CO2 Emissions, Real GDP, Renewable Energy and Tourism: Evidence From Panel of the Most-Visited Countries
(Cesky Statistical office, 2017) Dogan, Eyup
Previous studies on the energy-environment-growth literature overlook the investigation of the most-visited countries. Since these countries do not only belong to the largest economies and the top carbon dioxide (CO2) emitters in the world but are also listed in renewable energy country attractiveness index, this study analyzes the impacts of real GDP, renewable energy and tourism on the level of CO2 emissions for the top 10 most-visited countries. Applying several panel econometric approaches, we find out that renewable energy mitigates the pollution whereas real GDP and tourism contribute to the level of emissions. Thus, regulatory policies are necessary to increase the awareness of sustainable tourism. In addition, the use of renewable energy and the adoption of clean technologies in tourism sector as well as in producing goods and services play a significant role in CO2 mitigation.
Citation - Scopus: 2
Colibri: An International Blended Learning Experience Based on Real-World Problems
(University of Minho, 2016) Pedersen, Jens Myrup; Kuran, Mehmet Şükrü; Frick, Jan; Mank, Lea
Colibri is a European project funded by Erasmus+, where seven universities, a governmental organisation and two enterprises work together and explore new and innovative approaches to teaching. As part of the project we offer a joint course during the spring semester which was followed by 30 students in 2015. It contains both course and project activities. In this paper we describe our experiences from the project work, from the initial formulation of the project problems by the companies, over the organisation of the seminars and virtual collaboration phase to the final exams. The whole course was organised as follows: First there was a virtual kick-off meeting for all students and teachers. This was followed by a phase where students studied different modules online. Each student chooses an individual combination of modules that fits his/her background while also supporting the later project work. After the online modules, the students and teachers all meet physically for a week in Istanbul to finalize the modules and begin working on the real life projects provided by the enterprises. Then there was a period of virtual collaboration in the groups followed by the final seminar in Riga where everyone (students, teachers, and company representatives) met to finalize the projects, prepare for presentations/exams, and conduct examinations. Overall, the project was successful and received positive evaluations from the students, particularly regarding the international and interdisciplinary dimensions. On the other hand, we also learned how important it is to facilitate the collaboration, group work, and project planning during the first physical seminar. We found that it is both challenging and important to be very explicit about what exactly is expected from the students, as both students and supervisors have differing understandings of what a project is. Discussing the learning objectives with the students to obtain a common understanding can be a useful tool. © 2017 Elsevier B.V., All rights reserved.
Colorectal Cancer Prediction via Applying Recursive Cluster Elimination With Intra-Cluster Feature Elimination on Metagenomic Pathway Data
(Springer International Publishing AG, 2024) Temiz, Mustafa; Kuzudisli, Cihan; Yousef, Malik; Bakir-Gungor, Burcu
Advances in next-generation sequencing and in "-omics" technologies enable the characterization of the human gut microbiome. Colorectal cancer (CRC), the third most common cancer worldwide, is caused by genetic mutations, environmental influences, and abnormalities in the gut microbiota. The aim of this study is to identify pathways that influence host metabolism in CRC patients. The CRC-related metagenomic dataset used in this study contains the relative abundance values of 551 pathways calculated for 1262 samples. Here, two different approaches based on the feature grouping reduce the number of features by considering relevant features as groups, eliminate irrelevant features, and perform classification. The recursive cluster elimination with intra-cluster feature elimination (RCE-IFE) approach achieves anAUCof 0.72 using an average of 66.2 features on CRC-associated metagenomics dataset. In these experiments, P163-PWY: L-lysine fermentation to acetate and butanoate and PWY-6151: S-adenosyl-L-methionine cycle I pathways are identified as potential biomarkers associated with CRC. These experiments also reduce the number of features reported by both approaches in P163-PWY: L-lysine fermentation to acetate and butanoate and PWY-6151: Sadenosyl-L-methionine cycle I pathways reported by both approaches are considered possible CRC-related biomarkers. This study contributes to the molecular diagnosis and treatment of colorectal cancer by revealing the pathways associated with CRC. Our results are promising for the study of the gut microbiota and its role in CRC.
Citation - WoS: 3
Combined Effect of Midostaurin and Sphingosine Kinase-1 Inhibitor on FMS-Like Tyrosine Kinase 3 (FLT3) Wild Type Acute Myeloid Leukemia Cells
(Walter de Gruyter Gmbh, 2022) Sahin, Hande Nur; Adan, Aysun
Objectives Therapeutic potential of clinically approved FLT3 inhibitor midostaurin has been neglected in wild-type FLT3 positive acute myeloid leukemia (AML). Sphingosine kinase-1 (SK-1) having anti-proliferative functions is studied in various cancers, but not in FLT3 wild-type AML. We aimed to develop new therapeutic strategies to combat FLT3 wild-type AML by combining midostaurin with SK-1 inhibitor (SKI II) in THP1 cells. Methods The anti-proliferative effects of midostaurin, SKI II and in combination on THP1 cells were determined by MTT assay. The combination indexes were calculated using calcusyn software. SK-1 expression and PARP cleavage were checked by western blot. Cell cycle distributions (PI staining) and apoptosis (annexin-V/PI dual staining) were assessed by flow cytometry for each agent alone and in combinations. Results Midostaurin decreased SK-1 protein level. Midostaurin, SKI II and certain combinations decreased cell viability in a dose dependent manner. The combined anti-leukemic effects of the aforementioned drug combination afforded additive effect. Co-administration induced both necrosis and apoptosis via phosphatidylserine externalization, PARP cleavage and cell cycle arrest at G0/G1 and S phases. Conclusions Targeting sphingosine kinase-1 together with FLT3 inhibition could be a novel mechanism to increase limited clinic response to midostaurin in wild-type FLT3 overexpressing AML after further pre-clinical studies.
Citation - Scopus: 3
Combined Effect of Midostaurin and Sphingosine Kinase-1 İnhibitor on FMS-Like Tyrosine Kinase 3 (FLT3) Wild Type Acute Myeloid Leukemia Cells
(De Gruyter Open Ltd, 2022) Şahin, Hande Nur; Adan, Aysun
Objectives: Therapeutic potential of clinically approved FLT3 inhibitor midostaurin has been neglected in wild-type FLT3 positive acute myeloid leukemia (AML). Sphingosine kinase-1 (SK-1) having anti-proliferative functions is studied in various cancers, but not in FLT3 wild-type AML. We aimed to develop new therapeutic strategies to combat FLT3 wild-type AML by combining midostaurin with SK-1 inhibitor (SKI II) in THP1 cells. Methods: The anti-proliferative effects of midostaurin, SKI II and in combination on THP1 cells were determined by MTT assay. The combination indexes were calculated using calcusyn software. SK-1 expression and PARP cleavage were checked by western blot. Cell cycle distributions (PI staining) and apoptosis (annexin-V/PI dual staining) were assessed by flow cytometry for each agent alone and in combinations. Results: Midostaurin decreased SK-1 protein level. Midostaurin, SKI II and certain combinations decreased cell viability in a dose dependent manner. The combined anti-leukemic effects of the aforementioned drug combination afforded additive effect. Co-administration induced both necrosis and apoptosis via phosphatidylserine externalization, PARP cleavage and cell cycle arrest at G0/G1 and S phases. Conclusions: Targeting sphingosine kinase-1 together with FLT3 inhibition could be a novel mechanism to increase limited clinic response to midostaurin in wild-type FLT3 overexpressing AML after further pre-clinical studies. © 2022 Elsevier B.V., All rights reserved.
A Comparative Study of Unet Variants for Low-Grade Glioma Segmentation in Magnetic Resonance Imaging
(Inonu University, 2025) Guzel, Yasin; Aydin, Zafer
Brain tumors originating from glial cells are pathological entities that significantly impact quality of life and are classified based on their malignancy into low-grade gliomas (LGGs) and high-grade gliomas (HGGs). While the more aggressive HGGs have been extensively studied, LGGs are of critical importance for early diagnosis due to their potential progression to HGGs if left untreated. This has driven researchers to develop methods for the rapid and consistent diagnosis of LGGs. In this study, three models—UNet, Transformer UNet, and Super Vision UNet—were comparatively evaluated for the automatic segmentation of LGGs using magnetic resonance imaging (MRI) data. Multimodal MRI scans from 110 patients, retrieved from The Cancer Imaging Archive (TCIA), were used to train the models. Performance was evaluated using Dice Coefficient, Tversky Index, and Intersection over Union (IoU) metrics. The Super Vision UNet achieves the highest Dice (0.9115) and Tversky (0.9154) scores, while the Transformer UNet attains the highest IoU (0.8789). Both advanced models demonstrate superior segmentation performance with lower loss values compared to the conventional UNet. Visual outputs indicate that the modern architectures delineate tumor contours with greater precision. These results highlight the effectiveness and reliability of contemporary UNet-based and Transformer-based architectures in segmenting complex tumor structures such as LGGs. Integrating these models into clinical decision support systems holds promise for enhancing the speed and accuracy of the diagnostic process. © 2025 Elsevier B.V., All rights reserved.
Citation - WoS: 2
Comparison of Deep Learning and Conventional Machine Learning Methods for Classification of Colon Polyp Types
(Sciendo, 2021) Dogan, Refika Sultan; Yilmaz, Bulent
Determination of polyp types requires tissue biopsy during colonoscopy and then histopathological examination of the microscopic images which tremendously time-consuming and costly. The first aim of this study was to design a computer-aided diagnosis system to classify polyp types using colonoscopy images (optical biopsy) without the need for tissue biopsy. For this purpose, two different approaches were designed based on conventional machine learning (ML) and deep learning. Firstly, classification was performed using random forest approach by means of the features obtained from the histogram of gradients descriptor. Secondly, simple convolutional neural networks (CNN) based architecture was built to train with the colonoscopy images containing colon polyps. The performances of these approaches on two (adenoma & serrated vs. hyperplastic) or three (adenoma vs. hyperplastic vs. serrated) category classifications were investigated. Furthermore, the effect of imaging modality on the classification was also examined using white-light and narrow band imaging systems. The performance of these approaches was compared with the results obtained by 3 novice and 4 expert doctors. Two-category classification results showed that conventional ML approach achieved significantly better than the simple CNN based approach did in both narrow band and white-light imaging modalities. The accuracy reached almost 95% for white-light imaging. This performance surpassed the correct classification rate of all 7 doctors. Additionally, the second task (three-category) results indicated that the simple CNN architecture outperformed both conventional ML based approaches and the doctors. This study shows the feasibility of using conventional machine learning or deep learning based approaches in automatic classification of colon types on colonoscopy images.
Citation - Scopus: 1
Comparison of Mechanical and Physical Properties of Screed With and Without Expanded Polystyrene (EPS) Particles
(Yildiz Technical University, 2022) Kiliç, Fikret Merih; Yorulmaz, Hediye; Özuzun, Sümeyye; Durak, Uğur; İLkentapar, Serhan; Karahan, Okan; Atis, C. D.
In this study, in order to observe the mechanical and physical properties of ordinary screed, sandy-lightweight screed and lightweight screed samples, expanded polystyrene (EPS) was used as fine aggregate and lightweight screed systems were produced by replacing sand at 100%, 50% and 0%. Samples of cement dosages of 250, 300, 350 kg/m3 were produced for lightweight screeds, sandy-lightweight screeds and ordinary screeds. Unit weight, water absorption capacity, flexural strength, compressive strength, fire resistance, abrasion and thermal conductivity tests were performed on the produced screed systems. As a result of the research, it was determined that as EPS ratio increases in screed system; unit weights decreased, water absorption rates increased. Besides, the flexural and compressive strengths, fire and abrasion resistance are also decreased. However, it was observed that the thermal conductivity coefficient reduced with the increment of EPS particles in the screed. In normal, sandy-lightweight and lightweight screeds, it was determined that as the cement dosage increased; the unit weights, flexural and compressive strengths, fire and abrasion resistance increased, water absorption capacity and the thermal conductivity coefficient decreased. © 2022 Elsevier B.V., All rights reserved.
Citation - WoS: 11
Citation - Scopus: 15
A Comparison of Proactive and Reactive Environmental Strategies in Green Product Innovation
(Inderscience Publishers, 2019) Genç, Ebru; Di Benedetto, C. Anthony; Anthony Di Benedetto, C.
Companies are exposed to different kinds of pressures to respond to environmental sustainability issues. It is critical to understand how firms integrate environmental issues into their corporate agendas and how these integration strategies affect corporate performance. This paper investigates factors that motivate firms to adopt environmental marketing strategies and their relative impact on green product innovation performance. A comprehensive conceptual framework is developed and tested that portrays the antecedents and consequences of environmental marketing strategy (EMS). The results show that developing environmental strategies that exceed regulations (proactive strategies) leads to better new product performance than those that only adhere to regulations (reactive strategies). In addition, we find that commitment from top management becomes critical only for proactive strategies, not for reactive strategies. Finally, with regard to the consequences, we show that environmental marketing strategies lead to new product advantage and, ultimately, improved sustainable new product performance. © 2021 Elsevier B.V., All rights reserved.

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