Wos İndekslenen Yayınlar

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12597/3196

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Some Approximation Properties of the (p,q)-Stancu-Schurer-Bleimann-Butzer-Hahn Operators
(2024.01.01) Torun, G.
In this article, the p,q-Stancu-Schurer-Bleimann-Butzer-Hahn (p,q-SSBBH) operators are introduced. The Korovkin-type theorem is obtained to show the approximation properties of these operators. Then, the rate of convergence of these operators with the help of the modulus of continuity and Lipschitz-type maximal functions is calculated, respectively. Finally, for the asymptotic behavior of these operators, the Voronovskaja-type theorem is given. Furthermore, the convergence of these operators to the considered function f by plotting the graphs is demonstrated. And, this convergence is compared with the convergence of the p,q-Bleimann-Butzer-Hahn (p,q-BBH) operators to the same function.
Environmental effects of acid mine drainage and rehabilitation options at closed mine site: a case study
(2024.01.01) Konanç, M.U.; Degermenci, G.D.
rregular waste storage at closed mine sites poses severe environmental problems. This study evaluates the concentrations and effects of trace elements released into the environment by mining activity by analyzing soil, water, and sediment samples taken from a copper mining site. According to the data, acidic mine drainage was the main cause of the high concentrations of trace elements in the soil and sediments, including arsenic (As), cadmium (Cd), lead (Pb), and copper (Cu). The concentrations of As, Cd, Pb, and Cu in soil and sediments were 2734-times, 1189-times, 157-times and 32 times higher, respectively, in comparison to the background values of averaged concentrations of these elements in the upper crust. Geological and statistical studies indicate that the primary constituents of these pollutants are chalcopyrite and pyrite derivatives present in the primary rock structure. Using water analysis data from 2011 to 2020, the release of essential trace element into water was investigated to monitor the environmental effects of acidic mine drainage (AMD) from the closed Kuvarshan copper mine in the Artvin region of Turkey. This study demonstrates that trace elements concentrations may change according to local and seasonal factors and highlights the importance of conducting routine environmental monitoring studies.
Multi-dimensional analysis of land use/land cover and urbanization on seasonal variation of land surface temperature in İzmir, Türkiye
(2024.01.01) Isinkaralar, O.; Isinkaralar, K.; Yilmaz, D.; Öztürk, S.
Climate change-induced extreme meteorological phenomena, such as sudden temperature fluctuations, are raising global concerns. Increasing their adaptation capacity against temperature changes between seasons is becoming a more critical issue. The aim of this paper is to explore the association between surface temperature (ST) during the four seasons and urban geography in the city center of Izmir. The study identifies built environment parameters that impact seasonal land surface temperatures (LST) through spatial and statistical analysis at the local scale. At the same time, QUADRANT analysis revealed the spatial distinction between neighborhoods showing high LST compliance on a local scale (cooler summers and warm winters as well as neighborhoods showing LST sensitivity (hotter summers and colder winters. A spatial distinction is also revealed, showing significant differences in vegetation, number of buildings, building heights, and land use/cover change types. Geographic regression simulations show that the density of vegetation is vital in mitigating seasonal LST values, especially in making summers cooler and winters warmer. At the same time, population and built-up area density also play a role in increasing LST. Findings are consistent for neighborhood-scale analyses. Variables explain 26% in autumn, 31% in winter, 34% in spring, and 43% in summer. The study, which reveals the pressure of population and urbanization on temperatures, also highlights the adaptive character of the environment in adjusting the temperatures.
Impact of Acadian Marine Plant Extract Powder (AMPEP) concentration in nutrient medium on the growth and lipid accumulation of Chlorella sp. Culture
(2024.01.01) Sarri, J.H.; Erbil, G.C.; Elp, M.
Microalga of the genus Chlorella has developed a stable industry as dietary supplements for humans and animals based on their scientific and commercial interests. The growth of Chlorella sp. cultures has been enhanced by using a variety of nutrients to improve pigmentation, lipid content, and growth. Acadian Marine Plant Extract Powder (AMPEP) improves crops and macroalgae production, such as seaweeds. However, AMPEP has not yet been studied as a means of producing microalgae. Therefore, this study investigates microalgae production in a nutrient medium containing AMPEP. Three concentrations of AMPEP were prepared: group A (125 mg L-1 AMPEP), group B (625 mg L-1 AMPEP), and group C (0 mg L-1 AMPEP) as control. Experiments were conducted for each group for 21 days in triplicate. Results revealed that lower AMPEP (125 mg L-1) concentration added to the nutrient medium provides higher cell densities in Chlorella sp. culture. 125 mg L-1 AMPEP in a nutrient medium reached the highest cell density of 1.28 fold cell mL- 1 than the control group. Additionally, the dry weight of groups A, B, and C were calculated as 2.57 +/- 0.12 g L-1, 1.37 +/- 0.06 g L-1, and 1.58 +/- 0.16 g L-1, respectively. The cell sizes of groups A, B, and C were 4.80 +/- 1.32 mu m, 5.20 +/- 1.87 mu m, and 3.80 +/- 0.79 mu m, respectively. Moreover, the highest level of lipid accumulation of Chlorella sp. culture was achieved by group B with a lipid content of 10.44 +/- 1.28 %, followed by group A with a lipid content of 8.55 +/- 0.80 %, which was higher than the control group (group C) with a lipid content of 7.04 +/- 0.93 %. Hence, the present study shows that AMPEP used in microalgae production may improve growth and lipid accumulation.
Prevalence, molecular identification and genotyping of the crayfish plague pathogen, Aphanomyces astaci in major narrow-clawed crayfish (Pontastacus leptodactylus Eschscholtz, 1823) populations from Türkiye
(2024.01.01) Akhan, S.; Çagatay, I.T.; Berber, S.; Tastan, B.; Tastan, Y.; Dalar, T.
Introduction Crayfish plague is considered the most important crayfish disease globally. It is caused by the fungus-like agent, Aphanomyces astaci. This study aimed to identify and determine the prevalence of A. astaci using PCR in narrow-clawed crayfish (Pontastacus leptodactylus) populations from across T & uuml;rkiye.Material and Methods A PCR was carried out with primers specific to the internal transcribed spacer region of the A. astaci pathogen on both telson and abdominal cuticle tissues from crayfish individuals from 41 different locations.Results Aphanomyces astaci was detected in the crayfish from 34 of the locations. Molecular diagnosis showed the prevalence rates of A. astaci to be between 0% and 68.2%. For 7 of the 34 locations, the strain of A. astaci was determined. Microsatellite analysis of tissue from individuals with positive PCR results revealed the A. astaci genotypes in seven populations. Genotype B was found to be the predominant genotype responsible for crayfish plague in Turkish crayfish populations. The Psl genotype (genotype B) was determined in six of the populations, and the As genotype (genotype A) was detected in only one.Conclusion Crayfish plague poses a significant threat to crayfish populations, necessitating the development of rapid, highly sensitive diagnostic methods. An understanding of the sensitivity of the PCR detection method and of the prevalence and genotyping of A. astaci in Turkish crayfish populations has been gained from this study.
Simultaneous clavicular hook plate fixation in bilateral distal clavicle fractures (Neer type II): A case report
(2024.01.01) Akar, B.; Ugur, F.
Rationale:Bilateral distal clavicle fractures (BDCF) are exceedingly rare types of fractures. This study aimed to evaluate the surgical treatment under a single anesthesia for trauma-induced BDCF (Neer type II) through a case report.Patient concerns:The patient brought to the emergency department due to a motor vehicle accident exhibited severe pain, tenderness, swelling, and deformity in both shoulder regions upon physical examination. No significant pain or tenderness was detected in other areas of the body. There were also no signs of additional neurological deficits or vascular pathology in the extremities.Diagnoses:Radiographic examinations led to a diagnosis of BDCF (Neer type II).Interventions:Surgical intervention involved the simultaneous application of a neutral-angled hook plate to both clavicles via open reduction.Outcomes:Postoperative radiographs taken at the 12th week demonstrated complete healing in both fractures and no functional limitations in shoulder movements.Lessons:BDCF can compromise the stability of the shoulder girdle, necessitating surgical intervention with anatomical reduction and rigid fixation.
Preliminary study on the impact of 900 MHz radiation on human sperm: An in vitro molecular approach
(2024.01.01) Keskin, I.; Karabulut, S.; Kaplan, A.A.; Alagöz, M.; Akdeniz, M.; Tüfekci, K.K.; Davis, D.L.; Kaplan, S.
The use of technologies that produce and emit electromagnetic fields (EMF) is growing exponentially worldwide. The biological effects of EMF-emitting equipment, such as mobile phones and other wireless devices, have been studied in the last decade using in vitro and in vivo methods. Infertility is a growing health problem, and nearly half of cases are because of male-factor. This study investigated the direct in vitro effects of 900 MHz radiation exposure on sperm parameters, genetic status, apoptotic markers, and the PI3K/AKT signaling pathway in healthy normozoospermic men. Semen samples were divided into four groups, two control (30 min and 1 h) and two EMF exposure (30 min and 1 h). Sperm parameters (motility, progressive motility, acrosomal index, morphology), genetic status (DNA fragmentation and chromatin integrity), apoptotic markers (cytokine-c and caspase-3 expression) and the PI3K/AKT signaling pathway (phosphoinoitide 3-kinase-PI3K- and phosphorylated AKT- p-AKT-) were analysed. Sperm motility were significantly reduced in 30 min EMF exposure while a significant increase in the expression of p-AKT were observed in 1 h EMF exposure group. An increased vacuolisation, acrosomal defect, extension of subacrosomal space, uncondensed chromatin structure, apoptotic signs and disrupted axoneme were observed in both EMF groups which were not observed in the control group. Other sperm parameters (morphology and acrosomal index), genetic status, apoptotic markers and the PI3K expression rates had no significant change.
Theoretical Structure of Circular Intuitionistic Fuzzy C Control Charts
(2024.01.01) Sentürk, S.; Gökkus, Z.; Atalik, G.; Ince, N.; Yazicioglu, A.Ö.
The fuzzy control charts are available tools for monitoring and evaluating the process, if the process includes vagueness. The main contribution of fuzzy control charts is to provide flexibility to the control limits. In the literature, there are many fuzzy control charts that conducted using various fuzzy numbers. In this paper, the statistical base of circular intuitionistic fuzzy c control charts were being proposed to the literature for the first time. In addition, an application was executed on a data set, and results were interpreted.
Determination of Sixteen Woody Species' Ability to Sequester Sr, Mo, and Sn Pollutants
(2024.01.01) Yigit, N.
This study aimed to determine the most suitable woody species that can be used to reduce the pollution of Sr, Mo, and Sn, which are heavy metals that are harmful to the ecosystem and human and environmental health. Within the study's scope, samples were taken from the wood parts of 16 woody species growing under similar conditions in D & uuml;zce province, which is among the five cities with the most polluted air in Europe. The wood part is the largest organ of higher plants in terms of mass; it traps heavy metals within itself for many years and can remove heavy metals to a great extent. Therefore, plants with a high potential for heavy metal accumulation in the wood part are among the most suitable plants for phytoremediation studies. The study determined Sr, Mo, and Sn concentrations in the wood parts of 16 tree species via inductively coupled plasma optical emission spectroscopy and compared them using statistical methods. Results indicate that Robinia pseudoacacia and Cedrus atlantica species were suitable for reducing pollution by Mo and Sn, while Platanus orientalis and Populus alba species were suitable for reducing Sr pollution.
Variations in Sr, Tl, and V Concentrations at Copper Mining Sites Based on Soil Depth, Plant Species, and Plant Organ
(2024.01.01) Ergül, H.A.; Kuscü, I.S.K.
The concentrations of Sr, Tl, and V in soils and plant organs were evaluated at a copper mining site. These are heavy metals that are extremely dangerous and harmful to human and environmental health and, therefore, are on the ATSDR substance priority list. Within the scope of the study, soil samples were taken from different soil depths in the spoil area, the rehabilitation area where planting was performed and adult trees that were at least 20 years old, and the forest area. Soil samples were taken from the rehabilitation and forest areas where Pinus nigra Arnold., Pinus sylvestris L., and Robinia pseudoacacia L. species grow, and leaf, bark, wood, and root samples were taken from trees in the same areas. The study evaluated variations in heavy metal concentrations in soils based on species and soil depth and in plants based on plant species and organs. The study found that the heavy metal concentrations in soils and plant organs generally varied depending on plant species, while these variations were insignificant depending on soil depth. The highest concentrations by species were generally obtained for Sr in Robinia pseudoacacia and for Tl and V in Pinus nigra.
Phase change material incorporated paper pulp sludge/gypsum composite reinforced by slag and fly ash for energy efficient buildings: Solar thermal regulation, embody energy, sustainability index and cost analysis
(2024.01.01) Kucukdogan, N.; Sutcu, M.; Ozturk, S.; Yaprak, H.; Memis, S.; Gencel, O.; Ustaoglu, A.; Sari, A.; Hekimoglu, G.; Erdogmus, E.
This study focuses on the reuse of some industrial wastes in the development of innovative building materials and the thermal performance, environmental impacts and cost estimates of the gypsum composite material developed in the case of a phase change material impregnation. Lauryl alcohol (LA) was impregnated into paper pulp sludge (PPS) up to 45 % by weight without leakage to obtain shape-stable composites. The LA impregnated PPS (PPS/ LA) was replaced with PPS at 50 % and 100 % by weight in gypsum composite. Characteristics of shape-stable composites were studied. Also, the physical, mechanical, thermal properties and solar thermoregulation tests of the produced gypsum composites were examined in addition to the embodied energy, CO2 emissions and cost analysis. The melting and solidification enthalpies of PPS/LA were found to be 100.4-100.1 J/g, with only a 0.5 % reduction in latent heat storage capacity after 500 cycles, and approximately 3 % after 1500 cycles. Although the presence of PPS/LA in the gypsum composite caused a slight decrease in compressive strength, it significantly improved solar thermoregulation performance, maintaining ambient temperatures 2.55 degrees C to 5 degrees C warmer at night and 5.3 degrees C to 13.8 degrees C cooler during the day. Gypsum composites containing the PPS/LA offer a suitable alternative for energy-efficient sustainable building application by reusing around 57 % of three different industrial wastes providing a waste-reducing environmental approach and a high level of indoor thermal comfort.
Sustainable Reinforcement of PLA Composites with Waste Beech Sawdust for Enhanced 3D-Printing Performance
(2024.01.01) Kartal, F.; Kaptan, A.
This study investigates the incorporation of waste beech sawdust (WBS) into polylactic acid (PLA) composites for use in additive manufacturing, with a focus on enhancing the mechanical performance and sustainability of 3D-printed components. WBS, a byproduct of industrial timber processing, was used in varying concentrations (0-20%) to produce PLA composite filaments through a single-screw extrusion process, which were subsequently used in fused filament fabrication (FFF). Mechanical properties including tensile, flexural, and impact strengths were evaluated alongside thermal stability and microstructural analysis. The results indicated that the addition of WBS led to increased stiffness and hardness of the PLA composites, with optimal mechanical performance observed at 5-10% WBS content. Beyond this concentration, significant reductions in tensile, flexural, and impact strengths were noted, likely due to poor particle dispersion and inadequate interfacial adhesion, as confirmed by scanning electron microscopy (SEM) analysis. Thermal stability analysis via thermogravimetric analysis (TGA) revealed a reduction in degradation temperature with increased WBS content, which may limit the use of these composites in high-temperature applications. Despite certain limitations, this research underscores the potential of WBS as a sustainable reinforcing agent in 3D-printed PLA composites. The incorporation of WBS contributes to environmental sustainability by utilizing waste materials while also reducing the dependence on non-renewable resources. The findings suggest that PLA-WBS composites, particularly at lower WBS concentrations, offer an effective balance between improved sustainability and mechanical performance, making them suitable for a range of 3D printing applications. Future studies should focus on enhancing filler dispersion and interfacial bonding to further optimize the properties of PLA-WBS composites.
SUSTAINABLE MOBILITY AND ELECTRIC VEHICLE ADOPTION: A STUDY ON THE IMPACT OF PERCEIVED BENEFITS AND RISKS
(2024.01.01) Yildiz, B.; Çigdem, S.; Meidute-Kavaliauskiene, I.
The shift towards sustainable transportation is becoming increasingly important as the negative impact of traditional fuel-powered vehicles on the environment becomes more evident. Electric Vehicles (EVs) are considered a viable solution to this problem, and understanding the factors that influence consumer intention to purchase EVs is crucial for their widespread adoption. This study investigates the factors that influence individuals' intention to purchase EVs. 4 independent variables were considered: Perceived Environmental Benefit (PEB), Perceived Performance Benefit (PPB), Perceived Performance Risk (PPR), and Perceived Financial Risk (PFR). A survey was conducted with 398 respondents, and the data collected were analysed using Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), and Structural Equation Modelling (SEM). The results indicate that PEB, PPB, PPR, and PFR have significant effects on Purchase Intention (PI). Specifically, PEB and PPB positively affect PI, while PPR and PFR negatively affect it. These findings suggest that improving the PEBs and PPBs of EVs and reducing perceived performance and financial risks could encourage more individuals to purchase them.
The Effect of Different Doses of Salt Stress on Germination and Emergence in Cannabis ( Cannabis sativa L.) Seed Treated with Pre-Salicylic Acid
(2024.01.01) Gul, V.; Sefaoglu, F.; Cetinkaya, H.; Dinler, B.S.
It is known that salinity stress, one of the abiotic stress factors, significantly limits the germination, growth, development, and crop yield of plants. Therefore, this study was conducted to evaluate the effects of salinity (control, 50, 100 ve 150 mM) on seed germination and the effect of salicylic acid (control, 0.25, 0.50, 0.75 ve 1.00 mM) on seed germination to improve salt tolerance in cannabis seeds. The physiological characteristics of the plant, such as germination percentage, germination duration, germination index, radicle length, plumule length, wet radicle weight, dry radicle weight, wet plumule weight, and dry plumule weight, were analyzed. Depending on the salinity application dose, it was observed that there was a significant decrease in the germination parameters of cannabis seeds compared to the control. It was observed that salicylic acid treatments under salinity stress positively affected all the characters examined and reduced germination arrest due to increasing concentration levels. Although it is recommended to prepare seeds with 0.5 mM salicylic acid pre-application dose against salt stress of the cannabis plant,it is essential to expand the studies on its transfer to practice. As a result, salicylic acid will provide positive results that can be transferred to practice by increasing the resistance of cannabis plants against salinity, especially in agricultural soils with salt problems, as it will be more sensitive to pests and diseases.
Investigation of the miRNA levels changes to acceptable daily intake dose pesticide mixture exposure on rat mesentery and pancreas
(2024.01.01) Sevim, C.; Tsatsakis, A.; Taghizadehghalehjoughi, A.; Ozkaraca, M.; Kara, M.; Genc, S.; Mendil, A.S.; Yeni, Y.; Nikolouzakis, T.K.; Ozcagli, E.
On the Properties of the Modified λ-Bernstein-Stancu Operators
(2024.01.01) Lin, Z.P.; Torun, G.; Kangal, E.; Kantar, U.D.; Cai, Q.B.
In this study, a new kind of modified lambda-Bernstein-Stancu operators is constructed. Compared with the original lambda-B & eacute;zier basis function, the newly operator basis function is more concise in form and has certain symmetry beauty. The moments and central moments are computed. A Korovkin-type approximation theorem is presented, and the degree of convergence is estimated with respect to the modulus of continuity, Peetre's K-functional, and functions of the Lipschitz-type class. Moreover, the Voronovskaja type approximation theorem is examined. Finally, some numerical examples and graphics to show convergence are presented.
Preparation and Characterization of Pyridin-2-amine Functionalized Thiadiazole-Embedded Polymer Inclusion Membrane and Utilization of Its Heavy Metal Transport Efficiency (vol 94, pg 2038, 2024)
(2024.01.01) Cicek, M.; Cay, S.; Engin, M.S.; Sener, N.; Aldwib, A.E.O.; Kalkan, S.; Gür, M.
Phylogenetic characterization of Cochroaches (Insecta: Blattaria) in Türkiye and determination of their vector potential for medically important parasites
(2024.01.01) Cevahir, F.; Düzlü, Ö.; Atelge, M.; Yildirim, A.
This study was performed to investigate the phylogenetic characters of the cockroaches in the Kayseri region for mitochondrial cytochrome c oxidase subunit I (mt-COI), mt-COII, and internal transcribed spacer-2 (ITS-2) gene regions. It was also aimed to determine their mechanical transmission of medically important parasites. PCR-restriction fragment length polymorphism (RFLP) was performed by using mt-COI, mt-COII, and ITS-2 DNA gene regions to identify cockroach species (n=220) collected from different regions. Differentiation of cockroach species was based on RFLP models using two restriction enzymes: AvaI and EciI. For phylogenetic analysis, mt-COI, mt-COII, and ITS-2 DNA barcode regions were amplified with standard primers. The obtained amplicons were purified and sequenced using the PCR primers. According to PCR-RFLP, the cockroach species were identified as Blattella germanica (n=105), Blatta orientalis (n=86), and Periplaneta americana (n=29). A total of 13 haplotypes were detected and maximum likelihood (ML) analyses revealed that the sequences of all three species showed a monophyletic structure for the three gene regions. The cockroaches were examined for the presence of parasites. It was found that of the 58 parasitic forms identified, 46 (79.3%) belonged to helminth species and 12 (20.7%) to protozoan species. The results showed that B. germanica (58.6%) had the highest prevalence, followed by Bl. orientalis (32.8%) and P. americana (8.6%). The results of the study not only contribute to the molecular epidemiology of cockroaches but also confirm their important role as mechanical vectors of protozoan and helminth parasites.
Synthesis, spectroscopic characterization, DFT studies and antioxidant activity of new 5-substituted isatin/thiosemicarbazones
(2025.01.01) Muglu, H.
A new series of thiosemicarbazone derivatives (1-8) were prepared and elucidated by FT-IR, 1H NMR, and 13C NMR spectroscopic methods and elemental analysis. In this study, in which the antiradical activities of 1,1diphenyl-2-picrylhydrazil (DPPH) were investigated, ascorbic acid was used as a reference antioxidant. Also, density functional theory (DFT) calculations were employed to investigate the structural and electronic properties of compounds, and the obtained data were utilized to elucidate antioxidant activity. In summary, the half maximal inhibitory concentration (IC50) values were calculated and had lower antioxidant activity than the standard ascorbic acid.
Genomic diversity of major tree species in the Eurasian relict forests of northern Iran (vol 20, 35, 2024)
(2024.01.01) Vatanparast, M.; Madsen, P.; Sagheb-Talebi, K.; Larsen, J.B.; Ayan, S.; Hansen, O.K.

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