Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

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Citation - WoS: 3
Citation - Scopus: 4
1,2-Diboranes With Strong Donor Substitutes: Synthesis, Ovicidal and Larvicidal Effect on Important Vector Species
(Elsevier, 2024) Bursali, Fatma; Sahin, Yueksel; Aygun, Muhittin; Sevincek, Resul; Biyik, H. Halil; Özgener, Hüseyin; Gurbuz, Burcin
Novel control products are needed in the control of important insects like mosquitoes which are developing resistance to insecticides and larvicides currently in the market. Boron compounds have been demonstrated to exhibit antibacterial and anticancer effects. 1,2-diboranes with a long history and importance in boron chemistry have been described. These compounds are synthesized from reactions of 1,2-dichlordiborane derivatives with lidium amides (ArNHLi/Et2NLi, etc.). In addition to the three previously synthesized diborane compounds, five novel 1,2-diborane compounds were synthesized in good yield using the same method for the first time. The structures of the novel derivatives were characterized by nuclear magnetic resonance spectroscopy, and the molecular structure of one of them (2a) was also demonstrated using single crystal X-ray diffraction. In this preliminary study, the ovicidal and larvicidal effects of new 1,2-diamino-1,2-diborane derivatives against Aedes aegypti and Aedes albopictus eggs and larvae were investigated for the first time. Of these, 2a and 2e showed the highest ovicidal activity against both species, while 7, 4 and 2d showed particularly high larvicidal activity. Some 1,2-diborane derivatives were found to be significantly toxic, with LC50 values ranging from 14,930 to 27,975 mu g/mL. Some derivatives (6, 2a, 2c) were less effective against mosquito larvae. 1,2-Diborane derivatives have high ovicidal and larvicidal effects on mosquitoes and are therefore potential candidates for the development of new larvicides. Further studies are needed to evaluate its mode of action and safety. Understanding their mode of action against mosquito development is crucial to optimizing their use and reducing the potential development of resistance. Their potential effects on other mosquito species and non -target organisms need to be investigated.
Citation - WoS: 6
Citation - Scopus: 7
1,2-Diborolanes With Strong Donor Substituents: Synthesis and High Antimicrobial Activity
(Academic Press, 2021) Şahin, Yüksel; Poyrazoğlu Çoban, Esin; Sevinçek, Resul; Bıyık, Halil H.; Özgener, Hüseyin; Aygün, Muhittin
1,2-diborolanes with strong and without strong donor substituents have been described, and are also referred to as 1,2-diboracyclopentane. The 1,2-diaryl/alkyl-amino-1,2-diboracyclopentanes 2, 3, and 4 were obtained in good yield after the reaction of 1,2-dichloro-1,2-diboracyclopentane 1 with ArNHLi and Me3Si-NR2. The structures of these new derivatives were characterized by nuclear magnetic resonance spectroscopy. The molecular structures of 2b, 2c, 2e, 4, and 5f were also determined by single-crystal X-ray diffraction. The newly synthesized 1,2-borolanes are stable in air and showed particularly high activity against some Gram-positive bacteria. © 2020 Elsevier Inc.
Citation - WoS: 2
Citation - Scopus: 3
1-Octanol Is a Functional Impurity Modifying Particle Size and Photophysical Properties of Colloidal Zncdsse/Zns Nanocrystals
(American Chemical Society, 2021) Sevim Ünlütürk, Seçil; Çağır, Ali; Varlıklı, Canan; Özçelik, Serdar
Impurities in trioctylphophine (TOP) strongly affect nanocrystal synthesis. 1-Octanol among other contaminants in TOP is identified for the first time as a functional impurity by H-1 NMR. The deliberate addition of 1-octanol into trioctylphosphine reduced particle size and modified photophysical properties of ZnCdSSe/ZnS colloidal nanocrystals. NMR analysis furthermore revealed that 1-octanol is bonded to the nanocrystal surfaces. The ratio of integrals for the O-CH2 protons of 1-octanol, which is the lowest compared to the other ligands, suggests that 1-octanol plays a critical role to tune the particle size of nanocrystals. The increased amount of 1-octanol added into TOP reduces the particle size from 9.8 to 7.2 nm, causing a progressive blue shift in the UV-vis and PL spectra but leaving the alloy composition unaffected. The rate of nonradiative processes is enhanced with the amount of 1-octanol added into TOP, correlating with higher dislocation density observed in the nanocrystals. As a conclusion, 1-octanol is proposed as a functional impurity that varies particle size and nonradiative photophysical processes in the ZnCdSSe/ZnS colloidal nanocrystals.
1960s Tax Law and Non-Muslim Exodus From Istanbul: Turkification of the City
(Taylor & Francis, 2023) Akpınar, İpek
This chapter discusses the urban consequences of the expulsion of Istanbul Greeks in 1964. It demonstrates the urban impact of the 16 March 1964 decree that terminated the residence of 12, 000 Greek passport holders in Istanbul (a population of 40, 000 with their relatives), who were given 24 hours to leave the city and allowed to carry only 20 kilograms of belongings or US$22 with them. The event also alarmed many other non-Muslim families to emigrate from Istanbul, while the city was receiving a large influx of immigrants from rural lands due to the growing industrialization and urbanization. Akpinar discusses the urban planning interventions in Istanbul under the Menderes and subsequent governments throughout the 1950s and 1960s as ad-hoc or intentional steps toward Turkification, in which discrimination and the resulting emigration of Istanbul Greeks played a significant part. © 2024 selection and editorial matter, Esra Akcan and Iftikhar Dadi; individual chapters, the contributors.
Citation - Scopus: 1
3-D Switching Fabric Node Design
(ACTA Press, 2004) Dinleyici, Mehmet Salih; Akın, Osman
In this work we investigate an all-optical switching node that can be controlled by means of a transient grating, which is formed by interference of two Gaussian beams. This design considers 3-D architecture of switching fabrics.. real profile of Gaussian beams and fast switching time requirements. Four Wave Mixing (FWM) technique is applied in the evanescent field region of waveguide, showing chi((3)) nonlinearity. The formed grating is analysed by standart methods to obtain reflection coefficient and then coupling coefficient for power exchange between waveguides.
3d Modeling of a Historical Mine Waste Site Using Uav Images: Estimation of Stockpile Volumes
(Springer, 2023) Önal, Okan; Gündüz, Orhan
In recent decades, the use of Unmanned Aerial Vehicles (UAV) for land surveying became very popular because of their simplicity and low cost. Aerial images of the site can be used for the reconstruction of the site’s 3D digital model. Once proper calibrations are made, these digital models can be used for several purposes including stockpile volume estimation, stability analyses, forensic engineering and archiving, etc. In this study, the 3D model of an abandoned historical mine waste disposal site located in Balıkesir-Turkey was reconstructed for the estimation of the waste stockpile volumes. The historical mine site is a facility that was abandoned more than 80 years ago. Mine wastes of different quality were disposed of in and around the site along the hydrologically intermittent creek that passes through the site. No engineered precautions were taken at the site to reduce the environmental impacts and all waste piles were exposed to the natural eroding effect of precipitation and wind. The total amount of the waste volume is not known accurately, which prevents researchers to quantify the potential impacts associated with different waste stockpiles. Thus, a 3D digital model of the site was created by using UAV data obtained from a quadcopter and later processed to obtain a digital topography of the site with an improved accuracy value of ± 2 cm. The stockpiles were later analyzed with geographic information systems to characterize the magnitude of mine wastes and to propose alternative engineering solutions for environmental mitigation. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2023.
Citation - WoS: 4
Citation - Scopus: 4
3d Modelling of Surface Spreading and Underground Dam Groundwater Recharge: Egri Creek Subbasin, Turkey
(Springer, 2023) Şahin, Yavuz; Tayfur, Gökmen
This study investigated surface spreading and underground dam recharge methods to replenish groundwater in Turkey's Egri Creek Sub-basin of the Kucuk Menderes River Basin. A three-dimensional numerical model was employed for this purpose. Field and lab data are provided to the model for realistic simulations. Pumping test results were used to determine the aquifer parameters. The laboratory works involved sieve analysis, permeability tests, and porosity and water content prediction. The numerical model's boundary conditions were determined from the geological and hydrogeological characteristics of the study area. Initial conditions were expressed regarding water content and pressure head in the vadose zone. The numerical model was satisfactorily validated by simulating water levels in three different pumping wells in the study area. Seven different scenarios, each having a different pool size, were investigated for the surface spreading recharge method. The results showed that a pool size of 30 x 30 m with a 6-m depth basin was the most optimal choice, raising the groundwater level to about 29.3 m. On the other hand, it was found that an underground dam could raise the levels by an average of 9.5 m, which might not be significant to warrant the construction.
Citation - Scopus: 4
44 Current Challenges in Mirnomics
(Humana Press, 2022) Akgül, Bünyamin; Stadler, Peter F.; Hawkins, Liam J.; Hadj-Moussa, Hanane; Storey, Kenneth B.; Ergin, Kemal; Allmer, Jens
Mature microRNAs (miRNAs) are short RNA sequences about 18–24 nucleotide long, which provide the recognition key within RISC for the posttranscriptional regulation of target RNAs. Considering the canonical pathway, mature miRNAs are produced via a multistep process. Their transcription (pri-miRNAs) and first processing step via the microprocessor complex (pre-miRNAs) occur in the nucleus. Then they are exported into the cytosol, processed again by Dicer (dsRNA) and finally a single strand (mature miRNA) is incorporated into RISC (miRISC). The sequence of the incorporated miRNA provides the function of RNA target recognition via hybridization. Following binding of the target, the mRNA is either degraded or translation is inhibited, which ultimately leads to less protein production. Conversely, it has been shown that binding within the 5? UTR of the mRNA can lead to an increase in protein product. Regulation of homeostasis is very important for a cell; therefore, all steps in the miRNA-based regulation pathway, from transcription to the incorporation of the mature miRNA into RISC, are under tight control. While much research effort has been exerted in this area, the knowledgebase is not sufficient for accurately modelling miRNA regulation computationally. The computational prediction of miRNAs is, however, necessary because it is not feasible to investigate all possible pairs of a miRNA and its target, let alone miRNAs and their targets. We here point out open challenges important for computational modelling or for our general understanding of miRNA-based regulation and show how their investigation is beneficial. It is our hope that this collection of challenges will lead to their resolution in the near future. © 2022, Springer Science+Business Media, LLC, part of Springer Nature.
A Capsular Polysaccharide From a Healthy Human Microbiota Member Activates a Lag-3 Cell Axis To Restrain Colon Cancer and Augment Immunotherapy
(Elsevier B.V., 2025) Weis, Allison M.; Bauer, Kaylyn M.; Tang, William Weihao; Stephen Victor, Emmanuel; Bell, Rickesha S.; Brown, David Garrett; Swanson, Eric A.
Colorectal cancer (CRC) is increasing globally, making identification of preventative measures necessary. Transplantation of the microbiota from CRC and non-CRC patients into mice demonstrates that non-diseased individuals possess organisms that reduce tumor formation and highlights Bacteriodes uniformis as protective. B. uniformis is reduced in humans with CRC, and proactive treatment with B. uniformis slows tumor growth in mice. Natural killer (NK) cells, but not T cells, are required for B. uniformis-mediated protection. CRC is recalcitrant to immunotherapies; however, addition of B. uniformis restores response to α-CTLA-4 treatment in an NK cell-dependent manner. We report that high Lag-3 expression is associated with greater survival in CRC patients and that B. uniformis-mediated protection is reliant on Lag-3 in innate cells. Induction of NK cell activity and reduced tumor growth is dependent on a specific B. uniformis capsular polysaccharide. Thus, healthy individuals possess tumor suppressor microbes that prevent cancer development and can be harnessed therapeutically. © 2025 Elsevier B.V., All rights reserved.
A Chebyshev Wavelet Approach to the Generalized Time-Fractional Burgers-Fisher Equation
(Univ Tabriz, 2025) Aghazadeh, Nasser
This work proposes a new method for obtaining the approximate solution of the time-fractional generalized BurgersFisher equation. The method's main idea is based on converting the nonlinear partial differential equation to a linear partial differential equation using the Picard iteration method. Then, the second kind Chebyshev wavelet collocation method is used to solve the linear equation obtained in the previous step. The technique is called the Chebyshev Wavelet Picard Method (CWPM). The proposed method successfully solves the time fractional generalized Burgers-Fisher equation. The obtained numerical results are compared with the exact solutions and with the solutions obtained using the Haar wavelet Picard method and the homotopy perturbation method.
A Comparative Study on Experimental and FEA-Based Simulation of Dry Sliding Wear Behavior of Boronized AISI 304 Stainless Steel at Elevated Temperatures
(Pleiades Publishing Ltd, 2025) Gok, Mustafa Sabri; Kucuk, Yilmaz; Khosravi, Farshid; Gunen, Ali; Karakas, Mustafa Serdar; Guden, Mustafa
In this study, the influence of boronizing on the high-temperature wear behavior of AISI 304 was examined experimentally and with FEA simulation. Boronizing, conducted at 950 degrees C for 3 h using the powder-pack boronizing technique, showed an approximately 7-fold increase in hardness compared to untreated sample. Boride layer characterization was performed using XRD, SEM, and EDS line analyses. Wear tests were performed at ambient temperatures of 25, 250, and 500 degrees C. While the wear rates of the untreated sample increased dramatically with increasing temperature, those of the boronized samples were significantly limited. FEA simulation using the Johnson-Cook fracture model demonstrated a high degree of consistency with the experimental wear profiles and this alignment enables reliable wear predictions. The oxide layer formation was observed on the worn surface of boronized samples during the tests at elevated temperatures, resulting in less plastic deformation.
A Comprehensive Database and a New Model for the Axial Response of Heat-Damaged Concrete Before and After FRP Confinement
(Springer, 2025) Akdag, Nefise; Demir, Ugur
In this study, a total of 330 concrete specimens, compiled from existing experimental data, are systematically reviewed to assess their post-fire axial stress-strain behavior before and after circumferential confinement with fiber-reinforced polymers (FRPs). The selection criteria for the database are as follows: (i) studies had to be published in English, (ii) both lateral and axial ultimate strains must have been measured, (iii) the use of additional strengthening materials in combination with FRPs was excluded, (iv) only plain concrete specimens were considered, and (v) specimen dimensions and instrumentation details had to be explicitly reported. The dataset is structured to include heating/cooling and curing conditions, specimen properties, and FRP characteristics. Subsequently, the predictive accuracy of available models for post-fire axial strength and ultimate strain of concrete members, both before and after FRP confinement, is evaluated. The results based on the reviewed comprehensive database indicate that these models are inadequate in capturing the observed behavior in the experiments. As such, a new analytical model is developed based on the compiled dataset. The proposed model demonstrated reliable predictive performance in terms of post-fire axial response of concrete before and after FRP confinement while remaining user-friendly for practical engineering applications. This is done such that universal design guidelines on the behavior of heat-damaged concrete strengthened by FRP composites can be reliably formulated.
A Critical Analysis of Pulverization Mechanism During Hydrogen Decrepitation of End-Of Ndfeb Magnets
(Elsevier Science Sa, 2025) Habibzadeh, Alireza; Gokelma, Mertol
Given the increasing demand and limited availability of rare earth elements (REEs), innovative solutions are critical to managing supply risks. Recycling is a key strategy in mitigating these risks, particularly for NdFeB magnets, which consume a large portion of REEs. Among the various recycling processes, hydrogen decrepitation (HD) has gained popularity due to its efficiency in producing fine powders for magnet-to-magnet recycling. While the HD mechanism is commonly attributed to hydride formation in the Nd-rich grain boundary phase, this study presents new findings that challenge this assumption. Through the hydrogenation of End-of-Life (EoL) NdFeB magnets at temperatures ranging from 25 to 400 & ring;C, the results indicate that the primary mechanism of pulverization arises from hydride formation in the Nd2Fe14B matrix rather than in the Nd-rich phase, especially at low temperatures where NdH2 formation is kinetically unfavorable. This revised mechanism was supported by evidence from X-ray diffraction, BSE and SE-SEM imaging, particle size analysis, diffusion modeling, and stress analysis.
A Green Route to Albumin/Albumin Polyelectrolyte Complex Nanoparticles in Water With High Drug Loading for Drug Delivery
(Elsevier, 2025) Sozer-Demirdas, Sumeyra Cigdem; Erez, Ozlem; Cakan-Akdogan, Gulcin; Akdogan, Yasar
A polyelectrolyte complex (PEC) formation offers a simple and green approach to obtaining albumin nanoparticles (NPs) without the use of organic solvents, crosslinkers and specialized equipment. The prepared cationic albumin proteins interact with anionic albumin proteins to form albumin PEC NPs (110 nm) with +37 mV surface zeta potential. Furthermore, albumin PEC NPs preparation in water alone achieves chlorambucil (CHL) loading up to 17 times higher than the conventional desolvation method, largely due to the elimination of drug loss to organic solvents. CHL loaded albumin PEC NPs also decreased the cell viability (Huh-7) to 44 % within 24 h. This study demonstrates that high drug-loaded albumin NPs can be alternatively synthesized by using albumin polyelectrolyte properties, and applied in drug delivery applications.
A Hybrid Actuation System for Enhancing the Performance Metrics Related to Kinesthetic-Type Haptic Devices
(IEEE-Inst Electrical Electronics Engineers Inc, 2025) Kucukoglu, Sefa Furkan; Can Dede, Mehmet ismet
High torque to volume ratio, fast response, and high dynamic range are some of the desired performance metrics for kinesthetic-type haptic device actuation systems. In this article, we present a hybrid actuation system consisting of an active actuator and a magnetorheological fluid-based brake (MRF brake). MRF brake's tradeoffs, namely, off-state torque and slow response (compared to an electric motor), are investigated and resolved by this hybrid actuation system. First, the transient behavior of the MRF brake is investigated and an mathematical model is proposed to mimic its transient response behavior. It is found that the performance of the proposed model performs better than the conventionally used first-order transfer function. Second, hybrid actuation system is constructed. The active actuator is used for compensating for the speed of the response and the off-state torque based on the proposed mathematical model of the MRF brake. It is measured that the off-state torque is largely eliminated from 0.178 to 0.008 N center dot m, the dynamic range is enlarged from 15 to 42.4 dB, and its time constant is improved from 69.6 to 4.4 ms when the hybrid actuation system is used instead of just an MRF brake.
A Just Co-City
(TU Delft, 2025) Keskin, Eylem; Köse, Süheda; Yalçın, Zeynep Özge; Gürman, Aysu; Buldan, Ece
A Proposal of Indoor Air Pollutant Limit Values for Turkish Schools Based on a Literature Review of Emission Sources, Concentrations, Health Effects, and Limits/Guidelines
(Elsevier B.V., 2025) Sofuoglu, S.C.; Arı, A.; Ylmaz Civan, M.; Dumanoğlu, Y.; Güllü, G.; Menteşe, S.; Toksoy, M.
Limit Values Working Group (LVWG) was established under Indoor Air Quality Committee of Turkish Climatization Assembly of the Union of Chambers and Commodity Exchanges of Türkiye. LVWG was tasked with reviewing the pertinent literature on indoor emission sources, concentrations in schools, health effects, and existing limit and guideline values to identify the indoor air pollutants that need to be addressed and to be recommended a limit value for Turkish schools. LVWG members took responsibilities based on their individual expertise. The recommendations were concluded in consensus decision-making after in-group discussions. A total of 19 pollutants/pollutant groups (carbon dioxide, carbon monoxide, nitrogen dioxide, ozone, radon, volatile organic compounds, formaldehyde, trihalomethanes, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, brominated flame retardants, organophosphate esters, phthalate esters, particulate matter, bioaerosols (bacteria, fungi, viruses), microbial pollutants and allergens) were reviewed. Limit values were recommended for 11 pollutants/groups based on the current knowledge, i.e. pollutant health effects and indoor air concentrations taking into account the exposure duration, the prevalence of existing limit/guideline values and the health effects on which they are based. © 2025 Elsevier B.V., All rights reserved.
Citation - Scopus: 1
Abnormally Accumulated Gm2 Ganglioside Contributes To Skeletal Deformity in Tay-Sachs Mice
(Springer Heidelberg, 2024) Demir, Secil Akyildiz; Seyrantepe, Volkan
Tay-Sachs Disease is a rare lysosomal storage disorder caused by mutations in the HEXA gene, responsible for the degradation of ganglioside GM2. In addition to progressive neurodegeneration, Tay-Sachs patients display bone anomalies, including kyphosis. Tay-Sachs disease mouse model (Hexa-/-Neu3-/-) shows both neuropathological and clinical abnormalities of the infantile-onset disease phenotype. In this study, we investigated the effects of GM2 accumulation on bone remodeling activity. Here, we evaluated the bone phenotype of 5-month-old Hexa-/-Neu3-/- mice with age-matched control groups using gene expression analysis, bone plasma biomarker analysis, and micro-computed tomography. We demonstrated lower plasma alkaline phosphatase activity and calcium levels with increased tartrate-resistant acid phosphatase levels, indicating reduced bone remodeling activity in mice. Consistently, gene expression analysis confirmed osteoblast reduction and osteoclast induction in the femur of mice. Micro-computed tomography and analysis show reduced trabecular bone volume, mineral density, number, and thickness in Hexa-/-Neu3-/- mice. In conclusion, we demonstrated that abnormal GM2 ganglioside accumulation significantly triggers skeletal abnormality in Tay-Sachs mice. We suggest that further investigation of the molecular basis of bone structure anomalies is necessary to elucidate new therapeutic targets that prevent the progression of bone symptoms and improve the life standards of Tay-Sachs patients.
Citation - WoS: 7
Citation - Scopus: 9
Absorbance-Based Detection of Arsenic in a Microfluidic System With Push-And Pumping
(Elsevier, 2021) Karakuzu, Betül; Gülmez, Yekta; Tekin, H. Cumhur
Rapid and portable analysis of arsenic (As) contamination in drinking water is very important due to its adverse health effects on humans. Available commercial detection kits have shown low sensitivity and selectivity in analysis, and also they can generate harmful by-products. Microfluidic-based approaches allow portable analysis with gold nanoparticles (AuNPs) as labels. However, they need complex surface modification steps that complicate detection protocols. Due to the lack of precise sensing and affordable solution, we focused on developing a microfluidic platform that uses a push-and-pull pumping method for sensitive detection of As. In this detection principle, a sample is introduced in the microfluidic channel modified with -SH functional groups where As can bind. Then, AuNPs are given in the channel and AuNPs bind on free -SH functional groups which are not allocated with As. Absorbance measurements are conducted to detect AuNPs absorbed on the surfaces and the resulting absorbance value is inversely proportional with As concentration. The method enables detection of As down to 2.2 mu g/L concentration levels in drinking water, which is well-below the allowed maximum As concentration of 10 mu g/L in the drinking waters by the World Health Organization (WHO). The paper reveals that multiple push-and-pull pumping of fixed volume of sample and AuNPs with a syringe pump can improve the binding efficiency in the microfluidic channel. With this technique, low amounts of sample (1 mL) and short total assay time (25 min) are sufficient to detect As.
Citation - WoS: 3
Citation - Scopus: 9
An Acceptance Model for the Adoption of Smart Glasses Technology by Healthcare Professionals
(Springer, 2020) Ozdemir-Gungor, Dilek; Goken, Muge; Basoglu, Nuri; Shaygan, Amir; Dabic, Marina; Daim, Tugrul U.

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