Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(74)
- Akkurt, Nevzat(39)
- Celik, Erkan(35)
- Serdar, Osman(35)
- Güler, Ömer(33)
- Kutlu, Banu(32)
- Paksoy, Mehmet Yavuz(32)
- Yucesan, Melih(31)
- Tekin, H.O.(30)
- Yildirim, Numan(30)
- Yildirim, Nuran Cikcikoglu(30)
- ALMisned, Ghada(28)
- Mete, Suleyman(26)
- Danabas, Durali(20)
- Ince, Muharrem(20)
- Serin, Faruk(20)
- Ates, Mehmet(19)
- Can, Erkan(19)
- Onat, Onur(18)
- Benzer, Fulya(17)
- Kocabaş, Mehmet(17)
- Tanyol, Mehtap(17)
- Kizak, Volkan(16)
- Alataş, Mevlüt(15)
- Aydin, Rahmi(15)
- Kahraman, Gökhan(15)
- Kilic, G.(15)
- Polat, Alper(15)
- Susam, Selim Orhun(15)
- Xu, Qian(15)
- Aslan, Naim(14)
- Guler, Omer(14)
- Gürler, Nedim(14)
- Karatay, Gülnaz(14)
- Utku, Anıl(14)
- Yildirim, N. C.(14)
- Özkul, İskender(14)
- Demirol, Ferhat(13)
- Erguven, Gokhan Onder(13)
- Firat, Erhan(13)
Yayınlar
- MakaleYalnız künye2022Scopus SJRQ3Identification of Potential Inhibitors for Severe Acute Respiratory Syndrome-related Coronavirus 2 (SARS-CoV-2) Angiotensin-converting Enzyme 2 and the Main Protease from Anatolian Traditional Plants
Kılınç, Namık; Açar, Mikail; Tuncay, Salih; Karasakal, Ömer Faruk
Background: The 2019 novel coronavirus disease (COVID-19) has caused a global health catastrophe by affecting the human population around the globe. Unfortunately, there is no specific medi-cation or treatment currently available for COVID-19. Objective: It is extremely important to find effective drug treatment in order to put an end to this pandemic period and return to normal daily life. In this context and considering the urgency, rather than focusing on the discovery of novel compounds, it is critical to explore the effects of existing herbal agents with proven antiviral properties on the virus. Methods: Molecular docking studies were carried out employing three different methods, Glide extra precision (XP) docking, induced fit docking (IFD), and molecular mechanics/generalized born surface area (MM/GBSA), to determine the potential antiviral and antibacterial effects of 58 phytochemicals present in Rosmarinus officinalis, Thymbra spicata, Satureja thymbra, and Stachys lavandulifolia plants against the main protease (Mpro) and angiotensin-converting enzyme 2 (ACE2) enzymes. Results: 7 compounds stood out among all the molecules, showing very high binding affinities. Accord-ing to our findings, the substances chlorogenic acid, rosmarinic acid, and rosmanol exhibited extremely significant binding affinities for both Mpro and ACE2 enzymes. Furthermore, carnosic acid and alpha-cadinol showed potent anti-Mpro activity, whereas caffeic acid and carvacrol exhibited promising anti-ACE2 activity. Conclusion: Chlorogenic acid, rosmarinic acid, rosmanol, carnosic acid, alpha-cadinol, caffeic acid, and carvacrol compounds have been shown to be powerful anti-SARS-CoV-2 agents in docking simulations against Mpro and ACE2 enzymes, as well as ADME investigations.
AtıfScopus32WoS30OpenAlex31
İncele - MakaleYalnız künye2022Scopus SJRQ2Naphthol green B Removal using a Novel Hydrogel Composite: Thermodynamics, Isotherms, Kinetics and Optimization by RSM
Pıhtılı, Güzin; Tanyol, Mehtap; Birkan, Kubra
In this study, the efficiency of the Poly(4-vinylpyridine-co-acrylamide) doped with EuCl3 {(Poly(4-VP-co-AAM)/EuCl3)} hydrogel synthesized in the laboratory by free radical in-situ polymerization method in removing naphthol green B (NGB) from wastewater was investigated. The structural properties of the adsorbent have been described by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The dependence of NGB adsorption performance on varying such as the amount of adsorbent, initial NGB concentration and contact time were investigated in a batch system. To determine the interaction effects of the selected parameters on the adsorption process and to optimize the adsorption capacity of the process, the central composite design (CCD) in the response surface methodology (RSM) was used. Optimum conditions were found to be 110 mg/L NGB concentration, 0.05 g/100 mL Poly(4-VP-co-AAM)/EuCl3/EuCl3 dosage and 165.81 min contact time. The adsorption capacity and removal efficiency under these conditions were 206.46 mg/g and 92.50 %, respectively. Experimental equilibrium data were in better agreement with the Langmuir isotherm. The kinetic results indicated that the adsorption process can be defined by pseudo-second-order kinetic with internal diffusion as one of the rate-determining steps. The adsorption process was found to be exothermic and spontaneous. Experimental results showed that dye can be successfully removed from wastewaters using Poly(4-VP-co-AAM)/EuCl3 hydrogel as adsorbent.
AtıfScopus5WoS5OpenAlex6İncele - MakaleYalnız künye2022Scopus SJRQ3Plug-in Estimation of Dependence Characteristics of Archimedean Copula via Bézier Curve
Susam, Selim Orhun; Erdoğan, Mahmut Sami
• This article introduces measurement of the dependence between variables with a dependence structure defined by Archimedean copulas. The estimation of the dependence measure, such as Kendall’s tau as well as the lower and upper tail dependence, is investigated by using estimation of the Kendall distribution function based on the Bézier curve. A Monte Carlo study is performed to measure the performance of the new estimation method. The simulation results showed that the proposed methods has good results in terms of estimation performance. The new estimators are also used to estimate the dependence coefficients for three sets of real data.
AtıfScopus1WoS1İncele - MakaleYalnız künye2022Scopus SJRQ2Investigation of electrical conductivity and bioactive quality during ohmic evaporation process of Apple juice
Karakavuk, Emrah; Goksu, Ali; Sabanci, Serdal
In this study, the evaporation of apple juice was completed with ohmic heating to eliminate some problems with conventional evaporation methods. Ohmic evaporation (OE) was performed at different voltage gradients (13–17 V/cm) for determining electrical conductivity (EC), Hydroxymethylfurfural (HMF), and the total phenolic content (TPC) changes. The voltage gradient affected the total consumed energy, average power, and specific water removal ratio (SWRR) values (p <.05). The shortest time was obtained at 17 V/cm, while the longest time was 13 V/cm during the OE process. The EC value varies between 0.19–0.85 S/m for the voltage gradients. EC and current values increase with temperature until boiling starts, then decrease, and the EC value tends to increase slightly. The TPC value ranged between 587.4–716,4 mg GAE/100 g and was higher at OE than in the conventional process. As a result, the OE process preserves the TPC value of apple juice better while shortening the processing time. Novelty impact statement: The ohmic evaporation process is an alternative method that can be preferred in concentrating fruit juices with consuming less energy and obtaining higher quality products. In addition, considering the phenolic distribution, it was determined in this study that the products were better preserved in the ohmic evaporation process. It is predicted that it will provide important data for both pilot and industrial designs for the establishment of any ohmic evaporation systems.
AtıfScopus6WoS5OpenAlex9İncele - MakaleYalnız künye2022Scopus SJRQ1Occupational health, safety and environmental risk assessment in textile production industry through a Bayesian BWM-VIKOR approach
Ak, M. Fatih; Yucesan, Melih; Gul, Muhammet
Occupational risk assessment (ORA) is a process that consists of evaluating, ranking, and classifying the hazards and associated risks arising in any workplace from the viewpoint of occupational health and safety. Many ORA methods have been proposed in the literature, from a single independent expert to participatory methodologies made by group decision and simple to complex ones. In this paper, a holistic ORA is presented, which uses two important multi-attribute decision methods named Bayesian Best-Worst Method (Bayesian BWM) and VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR). Bayesian BWM is used to determine the importance weights of six different assessment criteria, which are the probability of hazardous event (P), frequency (F), severity (S), detectability (D), cost (C) and sensitivity not to use personal protective equipment (SNP). Since the classical BWM finds solution to the weights of a number of criteria from only one expert's judgment, Bayesian BWM is preferred in this paper (1) to enable participation of a group of experts, (2) to aggregate the preferences of these multiple experts into consensus without loss of information and (3) to follow a probabilistic way for solving the ORA problem. The hazards are then ranked by VIKOR. The approach is implemented in the ORA process of a textile production plant. Results of risk analysis showed that electricity hazard and associated risks constitute the highest risk ratings. These hazards arise from the product, process, human and working environment. The associated risks are evaluated, prioritized, and detailed control measures are proposed. This study made comparisons with the classical BWM-VIKOR approach to demonstrate the proposed approach's difference and practicality. Results can also help practitioners and risk analysts in formulating the improvement measures to increase the overall safety of the working environment further.
AtıfScopus87WoS78OpenAlex87İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ2Dental Material Detection based on Faster Regional Convolutional Neural Networks and Shape Features
Imak, Andaç; Çelebi, Adalet; Türkoğlu, Muammer; Şengür, Abdulkadir
In this paper, a novel approach is proposed to detect the dental materials in dental Panoramic images. In general, dental Panoramic images are examined by the dentists to detect the dental materials of the patients. Examining the dental Panoramic images is a time-consuming procedure and necessitates highly skilled dentists. Thus, computer imaging and decision support systems based on machine learning are in demand for dental applications. In this study, a semi-automatic, image processing and machine learning based approach is proposed for detection of dental materials in dental Panoramic images. More specifically, the dental materials namely dental filling, dental bridge and tooth crown are targeted by the proposed approach. Within the approach developed, the dental Panoramic images used as input are initially pre-processed for noise removal and tooth region is determined using a deep learning approach. To this end, a faster Regional Convolutional Neural Networks (RCNN) method is employed. A tooth region correction procedure is applied after application of faster RCNN to determine the exact location of the tooth region as faster RCNN may produce more tooth regions than one correct tooth region. Graph cut (GC) based image segmentation is applied to segment the tooth region into foreground and background regions. Shape based feature extraction and classification are applied to determine the tooth problem. A dataset has been established in dental faculty hospital of private dental clinics. The proposed approach is simple yet quite effective. In all classification methods, the average accuracy scores were around 90%.
AtıfScopus9WoS7OpenAlex10İncele - MakaleYalnız künye2022Scopus SJRQ2Performance evaluation of pectin extraction from grapefruit peel powder by ohmic heating
Goksu, Ali; Duran, Gülseven; Çilingir, Seda; Çevik, Mutlu; Sabanci, Serdal
This study is to investigate the performance properties during the extraction of pectin from grapefruit peel powder using ohmic heating. Pectin extraction was carried out under different voltage gradients (7–11 V/cm), different solid: liquid ratios (1:20–1:60), and different holding times (0–180 min) at constant pH and temperature (80°C). The voltage gradient and solid: liquid ratio affected the time to reach the target temperature. The highest energy efficiency value for all voltage gradients and solid: liquid ratios were obtained in the 0 min holding time, and the efficiency value, which changed between 89.47% and 56.02%, was negatively affected by the increase in the holding time. The exergy efficiency was lower than the energy efficiency and decreased due to the increasing holding time and decreasing voltage gradient. Also, the exergy efficiency was found to be between 73.69% and 18.09%. Determining the performance characteristics of the system will make a significant contribution to pilot and industrial-scale system/process applications for the future. Practical application: In this study, pectin was successfully obtained from grapefruit powder using an ohmic heating system. The operating conditions for the obtained pectin include constant pH (pH:1) and temperature (80°C) but various voltage gradients, solid: liquid ratios, and extraction times. It has been observed that voltage gradient and extraction time were effective on energy efficiency. When looking at exergy efficiency, voltage gradient, solid: liquid ratio, and extraction time were effective. It has been observed that the improvement potential (IP) value calculated for the system decreases depending on the increasing voltage gradient. The results obtained in this study are thought to be an important data source for literature, pilot, and industrial-scale production systems. It has been realized that ohmic heating, which is increasingly used, is an alternative technique for pectin production.
AtıfScopus13WoS12OpenAlex16İncele - MakaleYalnız künye2022Scopus SJRQ1Cooling of non-sloped, positively sloped, and negatively sloped arrangements of Li-ion batteries with a phase change material connected to a solar system
Akkurt, Nevzat; Aghakhani, S.; Mahmoud, Mustafa Z.; Abdelrahman, Anas
Three cylindrical Li-ion batteries are simulated using COMSOL Multiphysics in this study. A circular PCM layer is used to cover the batteries. A battery pack connected to a solar system is tested to store energy in a residential building. The PCM is 100% melted at the beginning, and the frozen PCM volume fraction (PVOF) is studied over time. In addition, the temperatures of individual batteries in three different configurations are analyzed at air velocities 1 and 3 mm/s. The three battery configurations included a positive slope, a negative slope, and no slope. The finite element method (FEM) is utilized to derive algebraic equations. The test results are given to the network as training data, and different neural network architectures are tested in terms of the number of layers and the number of neurons in each layer, and finally a structure that has a minimum mean squared error as a network. Battery behavior predictor is selected. Finally, this model is given to the optimization algorithm as an optimization function to investigate the point at which the maximum voltage is obtained. The results showed that the positively sloped battery configuration decreased the temperatures of the batteries, while the non-sloped configuration increased the temperatures. In addition, the positively sloped configuration resulted in more frozen PCM than non-sloped and negatively sloped configurations at a given time. The minimum frozen PCM was observed in the non-sloped configuration. A change in the air velocity from 1 to 3 mm/s increased the frozen PCM and improved the cooling of the batteries.
AtıfScopus15OpenAlex13İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ1Self healing of alkali active mortars with expanded perlite aggregate
Yılmazer Polat, Berivan
The use of alkali-activated mortars instead of cemented mortars provides an advantage in terms of various properties such as high strength, fast curing, and high durability by terminating cement production. However, concrete cracks reduce durability and strength, thus, it is crucial that they be healed. This study aimed to investigate the healing of early microcracks in geopolymer mortars by using Sporasarcina pasteurii, which makes carbonate precipitation, and expanded perlite aggregate as the bacteria carrier. This is the first study to investigate the bacterial healing of an alkali-activated geopolymer mortar using expanded perlite aggregate without applying a complex encapsulation process to the bacterial agents. For this purpose, optical, physical, and mechanical changes caused by self-healing were observed ahead of and after the cure period with tests like water absorption, compressive strength, UPV, SEM, FTIR, and optical microscope images. The results showed that bacterial cells could sporulate directly on the expanded perlite aggregate, visually improving the crack closure rate of the samples by a majority to 100 %, and the unit weights of all samples healed in DM and containing bacteria increased by up to 5 %.
AtıfScopus33WoS31OpenAlex28İncele - MakaleYalnız künye2022Scopus SJRQ2Characterization of the mechanical and thermal properties of rape short natural-fiber reinforced thermoplastic composites
Kısmet, Yılmaz; Dogan, Akar
In this study, the effects of filler amounts were studied on the mechanical and thermal properties of high-density polyethylene (HDPE), polystyrene (PS) and polyoxymethylene (POM) polymers reinforced with short rape fibers. HDPE-rape, POM-rape and PS-rape fiber composite materials were prepared with different fiber contents and their tensile, flexural, Izod impact and TGA/DTA properties were examined. When tensile and Izod impact properties were compared, it was observed that an increase in the amount of filling in HDPE-based composites did not cause any significant changes in these peoperties, while they were decreased for POM- and PS-based composites. On the contrary to tensile and impact strengths, when the three-point flexural properties were examined, it was observed that the strength values of all these materials increased with increasing the amount of fillers. However, a pronounced increase was observed in the three-point flexural strength of the HDPE-based composite materials. The flexural strength of 30 wt% rape-reinforced HDPE composite was found to be twice that of the pure HDPE. The results of TGA and DTA analyses revealed that the reinforcement element started to burn before the matrix material and therefore burning was delayed in these thermoplastics. As a result, the mechanical properties of HDPE composite materials improved with rape reinforcement. In this way, by using approximately 30 wt% natural filling material in a polymeric matrix, an environmentally friendly material, as well as, significant advantages in cost can be obtained. Graphic abstract: [Figure not available: see fulltext.].
AtıfScopus25WoS25OpenAlex33İncele - MakaleYalnız künye2022Scopus SJRQ2The effects of different packaging methods and sous vide cooking on chemical, sensory, and microbiological changes of marinated crayfish (Astacus leptodactylus Esch., 1823)
Kurt Kaya, Gülderen
Chemical and sensory parameters and the microbiological condition of marinated crayfish (Astacus leptodactylus), with emphasis on the quality and safety parameters, in brine, vacuum packaging (VP), and sous-vide cooking were investigated. Quality assessment of crayfish stored in in brine, vacuum packaging (VP), and sous-vide (SV) for up to 120 days at 4 ± 1°C was done by the monitoring of sensory parameters, microbiological condition, pH value, total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA), and peroxide value (PV). The highest concentration of TVB-N was recorded in the marinated crayfish stored under brine whereas the lowest TVB-N in the marinated crayfish stored under SV packed conditions. The concentration of TBA increased and its level reached over 5.44 mg MA/kg for crayfish stored in brine, 3.57 mg MA/kg for VP and 2.54 mg MA/kg for SV at 120 days. The formation of PV increased with the time of storage and was the lowest in the marinated crayfish stored in SV packed. During storage period, aerobic and anaerobic colony count, Escherichia coli, Coagulase positive staphylococcus, Listeria monocytogenes, Salmonella, and Clostridium perfringens were not found in any of samples. The marinated crayfish packed in sous-vide had extended shelf life at 4 ± 1°C compared to that packaged in brine and VP according to physicochemical analysis. Novelty impact statement: The biochemical quality degradation was considerably inhibited in SV-processed samples. Sous-vide packaging style had antioxidant activity. Crayfish processed by sous vide extended shelf-life to 120 days.
AtıfScopus5WoS5OpenAlex4İncele - MakaleYalnız künye2022Scopus SJRQ2Boron nitride nanosheet-reinforced WNiCoFeCr high-entropy alloys: the role of B4C on the structural, physical, mechanical, and radiological shielding properties
Kavaz, Esra; Gul, Ali Oktay; Basgoz, Oykum; Guler, Omer; ALMisned, Ghada; Bahceci, Ersin; Guler, Seval Hale; Tekin, H.O.
The synthesis and extensive characterization of newly developed boron nitride nanosheet (BNNSs)-reinforced WNiCoFeCr high-entropy alloys (HEAs) are presented. The influence of B4C on the structural, physical, mechanical, and nuclear shielding characteristics of synthesized HEAs has been widely examined in terms of its monotonic effects on the behavior changes. The internal morphology and structural characteristics of the fabricated composites are first investigated using X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. Wear testing is used to determine the coefficient of friction as a function of sliding distance. Experimental gamma ray and neutron setups are created to determine their shielding characteristics against nuclear radiation. Finally, the shielding characteristics of nuclear radiation for gamma ray and fast neutrons are compared extensively to those of many existing and new-generation shielding materials. Among the examined samples, the S2 sample with B4C and BNNSs reinforcement had the greatest mechanical characteristics. Our findings imply that increasing B4C directly contributes to the shielding qualities of nuclear radiation. The B4C created in the structure of BNNSs contributes to the overall properties of HEAs, which are crucial for nuclear applications, since HEAs are being examined as a component of future nuclear reactors. Additionally, B4C is a very versatile material that may be used in circumstances where mechanical and nuclear shielding properties need to be enhanced for a variety of radiation energies.
AtıfScopus11OpenAlex12İncele - MakaleYalnız künye2022Scopus SJRQ2A mathematical programming model for facility location optimization of hydrogen production from renewable energy sources
Derse, Onur; Göçmen, Elifcan; Yılmaz, Ebru; Erol, Rızvan
Fossil fuels are the primary energy sources and meet the global energy demands. However, environmental and health problems related with these sources boosted the demand for renewable energy sources. Hydrogen, as an energy carrier has a growing potential for solving these problems. In this article, a mathematical programming model that integrates the production, storage and transportation, safety, location, and staff assignment decisions is presented considering minimization of costs. Although most of the studies focus on location, distribution, storage decisions of hydrogen energy networks, the article also includes production, safety and staff assignment decisions to make this problem more practical. Furthermore, we also investigate the set covering constraint will ensure that each region is covered by minimum number of the hydrogen facilities. The developed model ensures a balance between location, distribution, storage, production, safety and staff decisions by installing two production facilities by assigning total 9 warehouses, 22 tank trucks, 12100 km pipeline, 35 staffs under distance constraint 2000 km in regions 1 and 5. The computational results indicate that the proposed model produces effective solutions for the coverage to all region and minimum total cost for real-case situations.
AtıfScopus20WoS16OpenAlex29İncele - MakaleYalnız künye2022Scopus SJRQ1The effect of pungency perception and personality traits on consumer's preferences from various regions of Türkiye for cig kofte, a traditional Turkish food
Boran, O.S.; Omac, B.; Gokce, Y.; Hayaloglu, A.A.
The aim of this study was to test whether personality traits influenced liking and choice of pungent foods such as cig kofte for Turkish population. In addition, we explored the role of demographic variables (gender and regions of Türkiye) and various concentration of capsaicin in cig kofte on the relation between personality traits and the frequency of annual cig kofte intake and liking of a spicy meal. Data of 316 participants from different region of Türkiye (47% women and 53% men) were examined. Participants were categorized for demographics, region, and personality traits (sensitivity seeking (AISS), sensitivity to reward (SR) and sensitivity to punishment (SP). They tasted cig kofte including various concentrations of capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide; 50, 75, 100, and 150 μM) and then evaluated liking and perceived intensity in it. A significant positive correlation was found between the liking of a spicy meal and frequency of annual cig kofte intake. Although a significant negative correlation was observed between the liking of a spicy meal and each concentration of capsaicin in cig kofte, no correlation was seen between the frequency of annual cig kofte intake and each concentration of capsaicin. In addition, the liking of a spicy meal was only associated with a personality trait, AISS, but the frequency of annual cig kofte intake was related to personality traits, AISS and SR. Besides, the relations between the frequency of annual cig kofte intake, liking of a spicy meal, personality traits (AISS, SR, and SP) and various concentration of capsaicin were influenced by both gender and region. Finally, no clear relationship was observed between liking and perceived intensity in cig kofte.
AtıfScopus4WoS4OpenAlex4İncele - MakaleYalnız künye2022Scopus SJRQ2Investigation of the changes in rheological properties and some quality characteristics of probiotic fermented almond milk with added different ratios of orange juice
Duran, Gülseven; Cevik, Mutlu
In this study, the changes in pH, titratable acidity, survival of Lactobacillus acidophilus, mold and yeast counts, rheological properties, and sensory evaluation of fermented almond milk samples with and without added 100% orange juice at three different ratios (10%, 20%, and 30%) were investigated. pH and titratable acidity values of fermented almond milk samples varied between 3.97–4.40 and 0.178%–0.478% at the end of the fermentation process, respectively. It was determined that the survival of L. acidophilus content of fermented samples varied between 7.58 and 7.95 log CFU/ml. The best suitable rheological model for the flow behavior of all fermented almond milk samples was the Power-Law model. Fermented almond milk samples with added 20% and 30% orange juice was more preferred by the panelists. It is thought that the results of this study could provide valuable information for equipment and pumping systems that can be installed on an industrial scale. Practical applications: In recent years, cereals (oats, rice, corn), legumes (soybean, cowpea, chickpea), oilseeds (sesame, sunflower, flaxseed), and hard-shelled fruits (almond, coconut, hazelnut, peanut, walnut) is widely used in the production of plant milk. In this study, the changes in some quality and rheological properties of fermented almond milk samples with added different ratios of orange juice were investigated. It was determined that all fermented almond milk samples had high probiotic content at the end of the fermentation stage. As a result of the sensory evaluation, it was determined that the acceptability of fermented almond milk with added 20% and 30% orange juice was very high compared to other samples.
AtıfScopus2WoS2OpenAlex2İncele - MakaleYalnız künye2022Scopus SJRQ2Synthesis, characterization, pH-sensitive swelling and antimicrobial activities of chitosan–graft-poly(hydroxyethyl methacrylate) hydrogel composites for biomedical applications
Torğut, Gülben; Yazdıç, Ferit Can; Gürler, Nedim
In this paper, 2-hydroxyethyl methacrylate (HEMA) was graft copolymerized onto chitosan (CHI) at different ratios using a radical initiator. The grafted hydrogel composites were then characterized by attenuated total reflection Fourier transform ınfrared spectroscopy (ATR-FTIR) and thermo-gravimetric analysis (TGA). Swelling behavior of the hydrogels was investigated at different pH and different times. The antimicrobial activity of the chitosan-graft-HEMA (CHI-HEMA) against gram-negative bacteria and gram-positive bacteria was studied by the standard agar well diffusion assay method. The CHI-HEMA 1:1 and CHI-HEMA 1:2 showed an obvious antimicrobial effect against six test strains. The CHI-HEMA 1:1 and CHI-HEMA 1:2 exhibited a highly significant increase (p < 0.01) in diameter of the inhibition zones compared with the standard antibiotics. Furthermore, CHI-HEMA 1:1 presented the highest antimicrobial activity against all test strains with a significant difference (p < 0.01) compared with CHI-HEMA 1:2. Meanwhile, the decreasing order of the average sensitivity to CHI-HEMA 1:1 and CHI-HEMA 1:2 was observed to be S. marcescens > E. coli > S. aureus subsp. aureus > S. enteritidis > E. faecalis > E. aerogenes. These results indicate potential application of CHI-HEMA 1:1 and CHI-HEMA 1:2 graft hydrogels as a novel and efficient antimicrobial agent in biomedical fields.
AtıfScopus40WoS36İncele - Kitap BölümüYalnız künye2022Metastasis inhibitory role of blueberries: time to play gooseberry with oncogenic cascades and metastasis
Farooqi, Ammad Ahmad; Ozbey, Ulku; Pimentel, Tatiana Colombo; Attar, Rukset
The magical little fruits have started to gain attention because of their cancer chemopreventive roles against different cancers. More recently, cancer inhibitory properties of blueberry extracts and isolated bioactive constituents have been described that provide new mechanistic insights. However, there are visible knowledge gaps in our understanding about metastasis inhibitory role of blueberries in xenografted mice. Despite mainstream popularization of cancer chemopreventive role of blueberries, many questions remain about their precise role in the regulation of deregulated oncogenic cascades in metastasis. It will be really exciting to consider how new scientific breakthroughs in future might propel the science of nutrigenomics to a more sophisticated level of inquiry.
AtıfScopus2OpenAlex1İncele - MakaleYalnız künye2022Scopus SJRQ1The influence of battery distance on a hybrid air-cooled cylindrical lithium-ion battery phase change material thermal management system for storing solar energy
Akkurt, Nevzat; Aghakhani, S.; Mahmoud, Mustafa Z.; Tag El Din, ElSayed M.
The cooling of a lithium-ion battery pack made up of three cylindrical batteries in a channel is studied using the finite element technique in this research. The phase change material (PCM) is surrounded by a laminar flow of air. The solid PCM fraction values and the average temperature of each battery and battery pack at various periods were studied by varying the distance between the batteries from 7 to 10 mm and adjusting the speed from 0.1 to 0.3 cm/s. When compared to other batteries surrounding this battery, the left battery had the lowest temperature and the maximum quantity of solid PCM was generated at various periods, according to the findings of this article. At 0.1 cm/s, the distance 7 mm is the greatest and the distance 8 mm is the lowest in the left battery, the distance 10 mm is the largest in the center battery, the distance 8 mm is the lowest in the right battery, and the distance 8 mm generates the least amount of solid PCM in the battery pack. The second and third batteries, as well as the battery pack, have the lowest average temperature across various distances of the batteries due to a distance of 10 mm between them. Increasing the speed from 0.1 to 0.3 cm/s causes the temperature to decrease in a time-dependent manner.
AtıfScopus37OpenAlex38İncele - MakaleYalnız künye2022Scopus SJRQ2Fault location method on two-terminal transmission line using synchronized time information of traveling waves
Akmaz, Düzgün; Mamiş, Mehmet Salih
In this study, approximate derivative (AD) signal processing method using synchronous voltages data, based on the traveling wave theory, was developed to determine fault locations in transmission lines. The first aerial mode voltage signals were obtained by applying the Clarke transformation to the voltage signals that occur after a short circuit fault. Then, by taking the first AD of the aerial mode voltage signals, the traveling waves were obtained. Finally, the location of the fault was found by using the time difference information of the traveling waves, wave velocity value and transmission line length. The proposed signal processing method was found to be effective in determining the location of faults. It was tested and compared to the discrete wavelet transform (DWT) for various fault conditions. Based on the simulation results, the proposed method was found to have a slightly higher success rate than DWT, in general. Moreover, it can work with low sampling frequencies, and it provides a better resolution than DWT to display the traveling waves in noise conditions.
AtıfScopus9WoS8OpenAlex7İncele - MakaleYalnız künye2022Scopus SJRQ1When did the North Anatolian fault reach southern Marmara, Turkey?
Karabacak, Volkan; Sançar, Taylan; Yildirim, Gökhan; Uysal, I. Tonguç
We dated syntectonic calcites on fault planes from the southern branch of the western North Anatolian fault (NAF) in northern Turkey using U-Th geochronology. We selected strike-slip faults that are kinematically related to the current regional strain field. The isotopic ages cluster around different periods during the past ~700 k.y. The most prominent cluster peak of 510.5 ± 9.5 ka (1σ) is consistent with the maximum cumulative strike-slip offset data and tectonic plate motions measured by GPS data, highlighting the fact that the present configuration of the NAF in the southern Marmara region started at ca. 500 ka or earlier. These new isotopic ages, combined with previous considerations of regional tectonics, reveal that faulting along the western NAF initiated primarily in the southern Marmara region at least a few hundred thousand years earlier than the timing suggested for the northern branch of the western NAF. This study presents an innovative approach to constrain the timing of initiation of currently active fault segments along the NAF in southern Marmara. U-Th geochronology of fault-hosted calcite thus has a wide application in determining absolute ages of fault episodes in wider shear zones along plate boundaries
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