Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(82)
- Akkurt, Nevzat(67)
- Güler, Ömer(66)
- Baskonus, Haci Mehmet(62)
- Bulut, Hasan(60)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(43)
- Yildirim, Numan(42)
- Yildirim, Nuran Cikcikoglu(38)
- Paksoy, Mehmet Yavuz(36)
- Serdar, Osman(36)
- Zengin, Gokhan(36)
- Ince, Muharrem(34)
- Celik, Erkan(33)
- Benzer, Fulya(32)
- Kocabaş, Mehmet(30)
- Sulaiman, Tukur Abdulkadir(30)
- Tanyol, Mehtap(29)
- Yildirim, Ozal(28)
- Aslan, Naim(26)
- Kök, Mediha(26)
- Özkul, İskender(26)
- Ates, Mehmet(25)
- Danabas, Durali(25)
- Kutluyer, Filiz(25)
- Can, Erkan(24)
- Kutlu, Banu(23)
- Onat, Onur(23)
- Demir, Veysel(22)
- Erten, Fusun(22)
- Guler, Omer(22)
- Say, Yakup(22)
- Güler, Seval Hale(21)
- Yaman, Mehmet(21)
- Baykal, Duygu Sen(20)
- Sançar, Taylan(20)
- Susam, Selim Orhun(20)
- Cakilcioglu, Ugur(19)
- Orhan, Cemal(19)
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ3Ten-Year Trends in Kidney Transplantation by Donor Type, Age, Dialysis, and Sex/Gender Inequality in Turkiye
Ordin, Yaprak Sarigol; Kankaya, Eda Ayten; Celik, Buket
Introduction: Gender disparity remains a global issue in access to renal replacement therapy and kidney transplantation among patients with end-stage kidney disease. Aim: This study examined trends in donor type, recipient age, and dialysis modality in kidney transplantation in T & uuml;rkiye from 2013 to 2022. A secondary aim was to explore gender disparities in kidney transplantation and treatment modalities for end-stage kidney disease using registry data. Methods: This descriptive and cross-sectional study analyzed the distribution and trends of kidney transplants in T & uuml;rkiye between 2013 and 2022. The data were obtained from the publicly accessible Registry of Nephrology, Dialysis, and Transplantation reports in Turkiye. Per million population increase/decrease rate, chi(2) linear trend, and chi(2) R by C were used. Results: Overtime, transplants from living donors increased, while deceased donor transplants decreased. The highest rates of living donor transplants were in 2022, 2021, and 2019. Transplants in high-risk age groups increased significantly. There were differences in donor type among patients receiving hemodialysis, peritoneal dialysis, or preemptive transplantation (p < .001). Preemptive transplants showed the most significant increase, especially from living donors in 2022. Between 2013 and 2022, kidney transplantation increased by 24.67% in men and 19.94% in women. Female transplant rates were lowest in 2016, 2020, and 2021, indicating a persistent gender gap. There was no significant gender difference in the incidence of hemodialysis or peritoneal dialysis. Conclusion: Living donor transplants, especially preemptive ones, increased markedly over the past decade. Gender disparities persist, and efforts should focus on improving access for women and promoting deceased donor programs to ensure equity.
AtıfWoS1OpenAlex1
İncele - MakaleAçık Erişim2026Piezoelectric energy harvesters in bridge structures: Evaluation of optimal placement and energy harvesting
Sen, Bugra; Polat, Alper; Kapicioglu, Abdullah; Esen, Hikmet
In the present study, energy is harvested from vibrations in bridge structures caused by vehicle passages using piezoelectric energy harvesters (PEHs). In order to maximize the energy harvested, it was aimed to specify the optimal locations of PEHs. In the study, energy harvesting from vibrations in bridge structures was achieved using three different vehicle loads and three different piezoelectric materials. The project of the Ku & scedil;saray & imath;-2 bridge, located in Ku & scedil;saray & imath; village in Baskil, Elaz & imath;& gbreve;, was modelled in the ANSYS program using real measurements. The bridge was analyzed for modal, harmonic, and piezoelectric energy harvesting, respectively. The type with the highest energy production was determined using three different piezoelectric materials (PZT-4, PZT-5A, and PZT-8) for a total of 9 PEHs, and a total of 13 different analyses were performed under three different vehicle loads (60 kN, 90 kN, and 120 kN) to compare the results. The maximum total power obtained from all nine PEHs was 1.484 & micro;W under the 120 kN load with PZT-5A. The maximum power obtained from a single PEH (PEH-1) was 0.49 & micro;W. This power achieved will be adequate for wireless sensor systems used for monitoring the structural health of bridges, and considering that energy harvesting through vibration is independent of meteorological elements, unlike energy sources such as solar and wind, the environmental damage caused by waste batteries in existing systems will be prevented with the dissemination of these systems. With the development of these systems, the energy needs of services such as lighting and traffic signs can be supplied. The results provide an important foundation for the development of vibration-based energy harvesting systems in bridge structures. Thus, the study stands out as an innovative step toward sustainable energy generation in structural engineering.
- MakaleYayıncıda açık erişim2026Scopus SJRQ1Effects of 8-week plyometric training program on balance, reaction time, and attention on elite adolescent female taekwondo athletes
Genç, Harun; Türkmen, Mustafa; Tekin, Irem; Cigerci, Ali Erdem; Gürses, Veli Volkan; Kizar, Oktay; Ökmen, Mehmet Serif; Polatcan, Ismail; Gündogdu, Serhat Dogu
Introduction: Taekwondo is a complex combat sport requiring high levels of strength, balance, reaction time, attention, agility, and endurance for effective performance under rapid offensive and defensive conditions. This study aimed to investigate the effects of an 8-week plyometric training program on static balance (SB), dynamic balance (DB), reaction time (RT), and attention (AT) in adolescent female taekwondo athletes. Methods: Twenty female athletes (age: 14.85 +/- 1.53 years; height: 162.27 +/- 7.12 cm; body mass: 56.69 +/- 6.45 kg) voluntarily participated in the study at Mardin Halit Demir Martial Arts Club. Participants were randomly assigned to either an experimental group (EG, n = 10) or a control group (CG, n = 10). The EG performed plyometric training twice weekly for 8 weeks in addition to regular taekwondo training, while the CG continued only taekwondo training. Static balance was defined as the primary outcome, whereas dynamic balance, reaction time, and attention were considered secondary outcomes. A 2 & times; 2 repeated-measures analysis of variance (group & times; time) was used to examine intervention effects. Results: Significant group & times; time interactions were observed for static balance and dynamic balance (p < 0.05), favoring the experimental group. However, no significant group & times; time interactions were found for reaction time or attention (p > 0.05). Discussion: These findings suggest that plyometric training may effectively improve balance performance in adolescent female taekwondo athletes, particularly static and dynamic balance. However, no significant effects were observed for reaction time or attention. Further studies with larger sample sizes are needed to clarify the potential effects of plyometric training on cognitive performance.
- MakaleYalnız künye2026Examining the Effect of Digital Sports Games on the Motivation Levels of Secondary School Students Regarding Participation in Sports Activities
Bozkurt, Eyup; Toker, Oguzhan; Aldim, Umit Ferit; Akgün, Tarik Fikret; Tümen, Tugba; Erdogan, Ramazan
The aim of this research is to examinethe effect of digital sports games on themotivation levels of secondary school students in participating in sports activities.The research was conducted using a correlational survey model, one of the quantitative research methods, and the researchgroup consisted of 141 volunteer students(80 male, 61 female) studying at the secondary school level in different provincesduring the 2024-2025 academic year. Apersonal information form and the DigitalSports Games Motivation Scale, developedby Kim and Ross (2006) and expanded byCianfrone et al. (2011), were used as datacollection tools. The SPSS software package was used for data analysis, and significance was accepted as p < 0.05. According to the research findings, it was determined that the students' motivation levels for digital sports games were generallyat a moderate level. The sub-dimensionswith the highest motivation were identified as team commitment, entertainment,and socialization. No statistically significant difference was found in digital sportsgame motivation levels according to gender, height, body weight, place of residence, income level, and parental educa-tion level variables (p > 0.05). Regarding the weekly digital game playing timevariable, a significant difference was foundonly in the entertainment sub-dimension;students who played digital sports gamesfor 5-8 hours a week had higher entertainment levels than the other groups (p <0.05). In conclusion, it can be said thatdigital sports games play a motivating rolefor secondary school students, especially inthe dimensions of entertainment and teamcommitment, but this effect is related togame time and the quality of interactionwith the game rather than demographicvariables. It is suggested that digital sportsgames should be considered not as an alter-native to physical sports activities, but as asupportive and complementary element tointerest in sports.
- MakaleAçık Erişim2026Scopus SJRQ1Ellagic Acid Mitigates Lead (Pb)-Induced Toxicity in Cyprinus carpio: A Multi-Biomarker Assessment of Hematological, Immunological, and Oxidative Stress Responses Supported by Molecular Docking
Eroglu, Mucahit; Cakmak, Mehmet Nuri; Pala, Aysegul; Uslu, Harun; Yonar, Serpil Mise; Ispir, Unal; Orhan, Cemal; Yonar, Muhammet Enis
Lead (Pb) is a widespread environmental pollutant that induces systemic toxicity in aquatic organisms primarily through oxidative stress, hematological disruption, and immune dysfunction. This study investigated the protective effects of ellagic acid (EA) against Pb-induced toxicity in common carp (Cyprinus carpio) using a multi-biomarker approach and molecular docking. Fish were assigned to six experimental groups: control, EA-treated, Pb-I, Pb-I + EA, Pb-II, and Pb-II + EA. Fish in the Pb-I and Pb-II groups were exposed to 2.5 and 5 mg/L Pb, respectively, while EA was administered via diet at 100 mg/kg for 14 days. At the end of the exposure period, hematological indices, innate immune parameters, and oxidative stress biomarkers were assessed in blood, liver, kidney, and gill tissues. Pb exposure caused marked hematological impairment, suppressed immune responses, increased malondialdehyde levels, and disrupted antioxidant defense by reducing SOD, CAT, GSH-Px, and GSH levels while increasing GST activity. In contrast, dietary EA supplementation significantly mitigated Pb-induced alterations, improved hematological and immunological responses, reduced lipid peroxidation, restored antioxidant capacity, and normalized GST activity to control levels. Molecular docking analyses further showed that EA interacts with hemoglobin and immunoglobulin M, supporting its potential role in preserving oxygen transport and immune functions under Pb-induced stress. Overall, the findings demonstrate that Pb-induced toxicity involves coordinated disruption of redox homeostasis and immune function, whereas EA exerts a multi-target protective effect through biochemical and molecular mechanisms. This study provides mechanistic insight into chemical-biological interactions and supports the potential application of natural bioactive compounds in mitigating heavy metal-induced toxicity.
- MakaleAçık Erişim2026Scopus SJRQ2A New Metacognitive Confidence Calculation Approach Based on Large Language Models for Natural Language Explanations
Yilmazer Gundem, Merve; Sahin, Simay; Karakose, Mehmet
Traditional methods used to measure metacognitive confidence rely on superficial features such as word count and ambiguity and therefore fail to adequately reflect the level of metacognitive confidence in statements. In this study, in addition to traditional text-based confidence measures, we used a Large Language Model (LLM) to directly analyze confidence and its ratio in statements. LLM-based confidence scores were calculated on statements from the e-SNLI and CoS-E open-source datasets, and the prediction performance obtained with traditional features was compared. The results indicate that traditional surface-level text features explain the variance in LLM-generated confidence scores to a limited extent, and that LLM-based scores are significantly correlated with independent researcher evaluations. This study contributes to the literature by offering a scalable and reproducible analytical framework for measuring metacognitive confidence. It is believed that the findings can be directly applied, particularly in applications where trust is critical, such as automated software test scenario generation, decision support systems, and risk management. The use of LLMs offers a framework for the LLM-based analysis of potential metacognitive confidence signals in natural language explanations by examining the sense of confidence and certainty with which statements are presented, rather than their factual accuracy.
- MakaleAçık Erişim2026Scopus SJRQ1A multi-evidence computational and experimental strategy for Silene nerimaniae: combining phytochemical characterization, bioactivity assessment, and ADEFRank-HCT-116-based metabolite prioritization
Erharman, Ahmet; Yagi, Sakina; Uba, Abdullahi Ibrahim; Nikolić, Filip; Gašić, Uroš; Acar, Mikail; Dogan, Nurettin; Koyuncu, Ismail; Yapıcı, Ismail; Gulcin, Ilhami
This study presents the first comprehensive evaluation of the phytochemical composition, antioxidant properties, enzyme inhibitory effects, and cytotoxic potential of Silene nerimaniae G.E.Genç, Kandemir & İ.Genç (family Caryophyllaceae). Ethyl acetate, acetone, 70% acetone, and aqueous extracts were obtained from the aerial parts of the plant through maceration. Among the tested extracts, the acetone extract contained the highest total phenolic (24.37 mg GAE per g) and flavonoid (24.64 mg RE per g) contents. LC–MS analysis identified 52 bioactive constituents, including sugars, organic acids, phenolic acids, flavonoids, and fatty acids. The aqueous extract demonstrated the strongest radical scavenging activity against DPPH (23.02 mg TE per g) and ABTS (55.76 mg TE per g), as well as the highest Fe3+ reducing power (37.53 mg TE per g). In combination with the acetone extract, it also exhibited notable Cu2+ reducing activity (47.78 mg TE per g). Regarding enzyme inhibition, the ethyl acetate, acetone, and hydroacetone extracts displayed the strongest inhibitory activities against acetylcholinesterase (1.87 mg GALA per g), butyrylcholinesterase (2.92 mg GALA per g), and tyrosinase (60.44 mg KAE per g), respectively. All three extracts also inhibited α-amylase activity within the range of 0.73–0.77 mmol ACAE per g (p ≥ 0.05). In addition, the hydroacetone extract showed considerable inhibition of human carbonic anhydrase isoenzymes I (IC50 = 38.78 μg mL−1) and II (IC50 = 19.59 μg mL−1). The ethyl acetate extract exhibited the strongest cytotoxic effect against the colorectal cancer cell line HCT-116, with an IC50 value of 0.639 μg mL−1 and a selectivity index of 1.7. To contextualize this HCT-116-associated activity at the metabolite level, an ADEFRank-HCT116 (abundance–domain–evidence fusion ranking) workflow was applied by integrating EtOAc abundance, HCT-116-oriented QSAR evidence, applicability-domain confidence, and structure-assignment reliability. This analysis prioritized diosmetin, luteolin, eriodyctiol, acacetin, and isorhamnetin as core candidates for structure-based follow-up. Molecular docking screening predicted favorable docking profiles for the prioritized candidates, while 100 ns molecular dynamics simulations were used to assess the dynamic stability of the representative luteolin–PI3Kα, diosmetin–AKT1, and isorhamnetin–GSK-3β complexes. Taken together, these results indicate that S. nerimaniae may represent a valuable source of active compounds for various functional nutraceutical, cosmetic and pharmaceutical uses. This journal is
- MakaleAçık Erişim2026Scopus SJRQ1Integrating experimental and atomistic insights into the rejuvenation of aged binder using bio-based rejuvenators
Kurban, Mustafa; Yalcin, Beyza Furtana; Yilmaz, Mehmet; Akpinar, Sinan; Kök, Baha Vural; Hekim, Seda; Özdemir, Ahmet Münir; Yalcin, Erkut; Göktaş, Fahrettin
This study integrates experimental and computational methods to evaluate the rejuvenation performance of an aged asphalt binder using two novel bio-based additives, 1T and 2T. The aged binder, sourced from reclaimed asphalt pavement (RAP), was modified with 25 wt% of each rejuvenator (denoted as 1T25 and 2T25, respectively). SARA (Saturates, Aromatics, Resins, Asphaltenes) fractionation and colloidal indices were used to assess compositional recovery. Both additives increased aromatic and resin contents while reducing asphaltenes. The 2T-modified binder achieved the highest colloidal stability (Ic = 0.29) and the most pronounced improvement in stability indicators (CI and Ic) among the tested systems. Complementary molecular dynamics (MD) simulations using the COMPASSII force field modeled the structural and thermodynamic behavior of RAP and rejuvenated systems. The 2T25 system exhibited higher density and more compact molecular packing, suggesting stronger cohesive organization and reduced free volume, whereas 1T25 showed greater molecular spacing and flexibility. RDF analysis and converged thermodynamic/structural trajectories (energy, temperature, cell length, and density stabilization) further supported rejuvenator-dependent rearrangement of packing during equilibration. Overall, MD acts as a mechanistic bridge that interprets experimental SARA/CI/Ic trends and supports design-oriented development of sustainable rejuvenators.
AtıfScopus2OpenAlex1
İncele - MakaleAçık Erişim2026Scopus SJRQ3Determination of Oxidative Stress Responses Induced by the Combination of 4 Different Rare Earth Elements in Dreissena polymorpha; [Determinacija odgovorov na oksidativni stres, ki ga povzroča kombinacija 4 različnih redkih zemljinskih elementov v Dreissena polymorpha]
Serdar, Osman; Aydin, Ayşe Nur
Rare Earth Elements (REE), whose usage areas are increasing day by day, are increasing in the amount of mixing with the environment, causing changes in antioxidant enzyme activities by causing oxidative stress in living organisms. In this study, it was aimed to examine the oxidative stress responses induced by the mixture of 4 different REEs (terbium, gadolinium, Lanthanum, Praseodymium) in Dreissena polymorpha. For this purpose, sublethal concentration values were determined by literature review. Experimental application was carried out within 24 and 96 hours. In the analyzes performed to determine biomarker responses, samples taken from living organisms were weighed and homogenization processes were performed for the analysis of samples taken from the experimental groups, including the control group. After homogenization, samples were centrifuged at 4.000 rpm for 15 minutes. Supernatants were kept at -86 °C until measurements were made. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities, and glutathione (GSH) and thiobarbituric acid reactive substances (TBARS) levels were determined using ELISA kits. Statistical analyses were performed using SPSS. One-way ANOVA (Duncan’s multiple range test; p < 0.05) was used for comparison of measured parameters among groups. As a result of the application, a decrease in CAT activity and GSH level and an increase in TBARS levels were observed after 96 hours compared to the control group, while no statistically significant difference was detected in SOD and GPx activities.
- MakaleYalnız künye2026Scopus SJRQ2An Investigation of the Variability of Short-Term Drought with SPEI-Based Severity, Duration and Magnitude Parameters in a Transboundary Basin
Akbas, Ergun; Acar, Ramazan; Eşit, Musa; Koycegiz, Cihangir
Climate change-induced variability in the water budget leads to significant drought events. In this study, severity, duration, and magnitude parameters obtained from 1-month and 3-month series of the Standardized Precipitation Evapotranspiration Index (SPEI) were used to investigate short-term drought from different perspectives. The lower part of the Euphrates-Tigris Basin, which is a transboundary basin, was preferred as the study area within the borders of Türkiye. In this study, monthly total precipitation and monthly mean temperature data for the period 1963–2021 were used. Both graphical (Şen Innovative Trend Analysis) and statistical (Mann–Kendall, Spearman’s Rho, Sen’s Slope Estimator) trend analysis methods were applied to detect, categorize, and analyze the variability of drought. The Combination of Wilcoxon Test and Scatter Diagram (CWTSD) method, which offers both graphical and statistical trend analysis capabilities, was preferred to enhance consistency and facilitate comparison of results. According to the findings, more severe droughts are observed in the eastern part of the basin compared to the western part. Across the basin, severity and magnitude are decreasing, while duration is increasing. The increase in duration indicates that droughts are shifting from short-term to long-term periods. This situation is of great importance in terms of planning agricultural strategies.
AtıfOpenAlex3İncele - MakaleYalnız künye2026Scopus SJRQ1Compositionally segmented thermoelectric BiSbTe thin films on Cr/Si(100)
Yüzüak, G. Durak; Yüzüak, E.
Compositionally segmented thermoelectric (CS-TE) structures improve thermal energy conversion efficiency across large thermal gradients. However, their increased design complexity complicates performance modeling and optimization. In this study, we fabricate CS-TE BiSbTe thin films on Cr-buffered Si(100) substrates. By adopting a multidisciplinary approach, we aim to broaden the technological applicability and strategic relevance of advanced TE systems. We systematically analyze the influence of deposition pressures (5, 7, and 10 mTorr) on TE performance. Variations in working pressure alter the Bi/Sb atomic ratio in the films, while the Te content remains stable. This enables the controlled formation of CS structures. At 323 K, the power factor (PF) of TE thin films reaches 0.7, 2.4, and 7.3 mW/mK2 under 5, 7, and 10 mTorr deposition conditions, respectively. The Cr-buffered layer significantly improves the electrical conductivity of CS-TE BiSbTe films. We further engineer a p-type single-leg device integrating nanostructured Bi0.35Sb1.65Te3, Bi0.37Sb1.63Te3, and Bi0.4Sb1.60Te3 layers. These materials are optimized to achieve peak TE PF values across a wide temperature range (320 to 500 K) while ensuring robust interfacial adhesion. The CS-TE device generates 3 mW/cm2, showing a 15% improvement over single-composition samples at a 100 K temperature difference.
AtıfScopus3WoS3OpenAlex2İncele - MakaleYalnız künye2026Scopus SJRQ1Innovative solutions for aquaculture: detecting fish diseases with hybrid deep learning model and explainable artificial intelligence
Utku, Anıl; Barut, Abdulkadir; Alofaysan, Hind
Early identification of fish diseases is critical to maintain aquaculture and minimize its financial burden. In the diagnosis of diseases, time is critical and scientists’ experience is imperative, which makes the artificial intelligence-based models necessary. It is intended by this study to integrate deep learning with explainable artificial intelligence methods to establish an artificial intelligence-powered framework for early detection of disease in fish. In this study, we developed a hybrid artificial intelligence system designed to detect diseases in freshwater fish by analyzing skin images. The primary objectives of the system are to minimize economic losses, prevent further disease spread, and ultimately increase aquaculture productivity. For this purpose, we used a dataset consisting of images from seven different disease categories, with 250 images in each class. A new hybrid model, Residual Network-50–Vision Transformer, was developed by integrating the strengths of Residual Network-50 and Vision Transformer architectures to improve classification accuracy. The proposed model was subjected to rigorous comparison with established architectures, including Visual Geometry Group 16, Mobile Convolutional Neural Network Version 2, Efficient Neural Network–Baseline Model B0, standalone Vision Transformer, and the original Residual Network-50. The results demonstrated that Residual Network-50–Vision Transformer outperformed the model, achieving an impressive 99.14% accuracy rate. Furthermore, the study employed local interpretable model-independent explanations to explain which image features most significantly influence the model’s classification decisions, thereby enhancing the interpretability and confidence in the model’s output. The application of such advanced image processing models in combination with explainable AI techniques demonstrates significant potential to support sustainable aquaculture by reducing disease outbreaks and associated financial losses.
AtıfScopus3OpenAlex2İncele - MakaleAçık Erişim2026Scopus SJRQ1Optimization, high-temperature resistance, and sulfate durability of basalt powder–blended alkali-activated slag mortars
Arslan, Furkan; Dener, Murat; Karataş, Mehmet; Benli, Ahmet
This study investigates the feasibility of using basalt powder (BP), an industrial by-product with limited reactivity, as a partial substitute for granulated blast furnace slag (GBFS) in alkali-activated systems. A comprehensive experimental program was conducted in two stages: first, a systematic optimization was performed by varying mixture parameters, including BP content, alkali dosage, activator modulus, and curing temperature to evaluate compressive strength development; second, selected binder compositions were used to produce self-compacting mortars, which were further examined for flexural strength, high-temperature resistance, and sulfate durability. The results demonstrated that moderate substitution levels (up to 20–30 % BP) could achieve satisfactory compressive strength, particularly under elevated curing temperature (60 °C) with 8 % Na2O and low to moderate modulus values. At 300 °C, mixtures with 20 % BP exhibited strength enhancement due to additional geopolymerization, demonstrating superior thermal stability compared to the control. Crucially, the incorporation of BP enhanced sulfate resistance, with the 40 % BP mixture exhibiting a slight increase in compressive strength after long-term exposure, in contrast to the marked deterioration of the GBFS-only system. Consequently, this study demonstrates that BP can be effectively utilized as a sustainable binder component, offering a practical solution for waste management while enhancing the durability of alkali-activated mortars against aggressive conditions.
AtıfScopus15WoS13OpenAlex10İncele - MakaleAçık Erişim2026Scopus SJRQ2Microstructure and Dry-Sliding Tribology of HVOF-Sprayed NiCrBSi/WC-Co Coatings on AZ91D
Gürgenç, Turan; Macit, Cevher Kürşat; Sömer, Medeni; Aksakal, Bünyamin; Ayık, Merve; Say, Yakup
High-velocity oxy-fuel (HVOF)-sprayed NiCrBSi coatings containing 0, 10, 30, and 50 wt.% WC-Co were evaluated on AZ91D magnesium alloy to determine how the discrete reinforcement level affects surface topography, phase constitution, Vickers microhardness, dry-sliding friction, mass loss, and wear-track microchemistry. As-sprayed surfaces were characterized by three-dimensional profilometry; coating cross-sections and worn surfaces by optical microscopy and SEM/EDS; phase constitution by XRD; and mechanical response by HV0.1 indentation. Dry-sliding tests were performed at 10, 30, and 50 N over 100–1000 m. Increasing WC-Co content raised Sa from 8.8 ± 0.3 to 13.0 ± 0.5 µm and Vickers microhardness from 776 ± 4 to 959 ± 5 HV0.1. XRD indicated a γ-Ni-based matrix containing boride/carbide constituents, while WC, W2C, and Co became increasingly prominent in the reinforced coatings. Boride assignments are based on diffraction evidence, whereas B and C EDS signals were treated semi-quantitatively. The 50 wt.% WC-Co coating exhibited the lowest mass loss and mean coefficient of friction at every load. Its mean friction coefficients were 0.31, 0.35, and 0.41 at 10, 30, and 50 N, corresponding to reductions of 40.1%, 38.9%, and 36.2% relative to AZ91D. At 1000 m, its mass-normalized wear rate indices were 9.0 × 10−4, 4.0 × 10−4, and 5.3 × 10−4 mg N−1 m−1, respectively. Post-wear mapping showed the largest field-scale W-Co-rich fraction in the 50 wt.% coating; however, isolated spectra containing more than 94 wt.% Mg are compatible with local coating penetration/substrate exposure and/or Mg-rich debris. The 50 wt.% composition therefore provided the best combined response among the four tested levels, while intermediate compositions are required to identify a continuous-composition optimum.
- MakaleYalnız künye2026Scopus SJRQ3New national and regional bryophyte records, 86
Wilbraham, J.; Abdirasulov, F.; Aguirre, J.; Alataş, M.; Álvaro Alba, W.R.; Aslan Ergenekon, Z.; Aswathy Raj, K.; Ayhan, E.; Batan, N.; Bednarek-Ochyra, H.
- MakaleYalnız künye2026Scopus SJRQ3Impact of ZnF2 and PbF2 on the radiation attenuation performance of the fluoride-based bismuth borate glass system
Aşkın, A.
Among the various types of glasses, fluoride-based glasses stand out due to their chemical and mechanical stability, low refractive indices, low phonon energies, and low transition temperatures. In this study, key radiation shielding parameters, including the mass attenuation coefficient (µm), half-value thickness (HVL), mean free path (MFP), transmission fraction (T), effective atomic number (Zeff), exposure build-up factors (EBF) and fast neutron removal cross-section (∑R), of the newly developed fluoride-based glass system, xZnF2—(25-x)PbF2—25Bi2O3—49.8B2O3—0.2Cr2O3 (where x is between 0, and 25 mol%), were evaluated. The data was gathered through Monte Carlo simulations, utilizing the Geant4 framework for a germanium detector and the PHY-X/PSD software. The parameters were assessed for gamma-ray energies ranging from 0.284 to 1.33 MeV across all glass samples. The results clearly show that the presence of PbF2 significantly enhances radiation shielding, owing to the high atomic number (Z) of lead. The highest µm and Zeff values were found to be highest and MFP, HVL, and T values were found to be lowest for the glass sample with the highest PbF2 content. Furthermore, the ∑R values of the glasses were observed to decrease as the PbF2 content reduced, highlighting the importance of high-Z elements in neutron absorption. Therefore, gamma and neutron shielding abilities of the studied glasses improve with the addition of PbF2 into the glass structure and glass system containing 25% mole PbF2 exhibits superior gamma and neutron shielding performance compared to shielding concrete.
AtıfScopus1WoS1İncele - MakaleYalnız künye2026Scopus SJRQ2A Bernstein polynomial estimation of the moment generating function
Susam, Selim Orhun
We study Bernstein polynomial smoothing for nonparametric estimation of the moment generating function (MGF) of a distribution supported on (Formula presented.). We prove strong consistency of the Bernstein-smoothed MGF estimator and show that, when the smoothing degree m grows sufficiently fast, it shares the same (Formula presented.) asymptotic normal distribution as the empirical MGF estimator, with variance (Formula presented.). A second-order bias–variance expansion reveals that Bernstein smoothing yields a bias of order (Formula presented.) and a variance-reduction term of order (Formula presented.). This leads to the optimal smoothing rate (Formula presented.) for pointwise mean squared error (MSE) minimization. Simulation results confirm that the Bernstein estimator is especially effective in challenging boundary-dominated settings, notably for U-shaped beta models and for larger positive t values. Overall, Bernstein polynomial smoothing provides a simple, theoretically justified, and practically effective tool for nonparametric MGF estimation on compact supports.
- MakaleAçık Erişim2026Scopus SJRQ2Which implant for Pauwels type 2 femoral neck fractures: a biomechanical study
Aydın, Oğuz; Kazez, Muhammed; Say, Yakup; Belhan, Oktay
Objective: Femoral neck fractures (FNF) in young patients are relatively rare but can lead to severe complications if not treated appro-priately. Pauwels type 2 fractures, characterized by moderate inclination, require surgical stabilization. However, no consensus exists regarding the optimal implant that provides superior biomechanical stability. This study aims to compare the biomechanical properties of 3 different fixation systems for the surgical treatment of Pauwels type 2 FNF. Methods: A total of 21 bovine femurs of similar age and size were selected and divided into 3 fixation groups: dynamic hip screw (DHS), cannulated screws (CS), and major plate (MP). Each specimen underwent axial compression testing to assess the maximum load-bearing capacity, shear force resistance, and deformation characteristics of the fixation methods. Results: The results showed that the CS group exhibited the highest shear stress resistance, followed by the DHS group, while the MP group showed significantly lower mechanical strength and elongation (P <.05). Although DHS provided substantial stability, CS demon-strated superior overall mechanical performance. In contrast, the MP system showed significantly lower resistance compared to the other 2 fixation methods. Conclusion: This biomechanical study highlights the importance of implant selection in the management of Pauwels type 2 FNF. Although previous investigations have questioned the adequacy of CS fixation in highly unstable Pauwels type 3 fractures, the results suggest that CS may be a reliable and effective option for the relatively more stable Pauwels type 2 pattern. Because the tests were performed on bovine femur models, which do not fully reflect the structural characteristics of human bone, these findings should be interpreted with caution. Further biomechanical studies using human cadaveric specimens are required to confirm the applicability of these results to clinical practice.
- MakaleAçık Erişim2026Scopus SJRQ1Effects of Melatonin Formulations on Caffeine-Evoked Cortical Activity and Pentobarbital-Induced Sleep in Mice
Sahin, Nurhan; Yabas, Mehmet; Er, Besir; Erten, Fusun; Kursun, Oznur Ece Durmaz; Cikim, Ismail Gurkan; Kaplan, Berkan; Erek, Gozde; Ozmen, Busra; Orhan, Cemal
Melatonin has chronobiotic, antioxidant, anti-inflammatory, and neuromodulatory properties, and its oral effects may vary according to formulation. This study compared conventional melatonin with a lipid-multiparticulate (LMP) formulation in two acute pharmacological mouse paradigms. Eighty-four male BALB/c mice were assigned to caffeine-evoked cortical activity or pentobarbital-induced sedative-hypnotic experiments. Mice received caffeine (7.5 mg/kg, i.p.) alone or with standard or LMP-melatonin (10 or 20 mg/kg, oral). ECoG recorded cortical electrical activity under urethane anaesthesia. In a separate cohort, latency to and duration of pentobarbital-induced loss of the righting reflex were measured. Circulating neurochemical and redox markers, as well as neurotransmitter- and inflammation-related gene and protein expression, were evaluated. Caffeine increased spike frequency and altered ECoG amplitude, together with unfavorable changes in circulating neurochemical and redox markers and in neurotransmitter receptor- and inflammation-related outcomes. Both melatonin formulations attenuated several of these changes in a dose-dependent manner, with the strongest effects generally observed in the high-dose LMP-melatonin group. Compared with conventional melatonin, LMP-melatonin produced greater modulation of ECoG activity, circulating biochemical markers, neurotransmitter-receptor expression, and IL-6 and TNF-α-related outcomes. LMP-melatonin also produced a greater reduction in the latency to and a greater prolongation of the duration of pentobarbital-induced loss of the righting reflex. LMP-melatonin produced greater formulation-dependent effects than conventional melatonin on caffeine-evoked cortical electrical activity, pentobarbital-induced sedative-hypnotic responses, and selected biochemical and molecular outcomes. However, pharmacokinetic exposure, physiological sleep stages, sleep architecture, sleep quality, and direct measures of neuronal injury were not assessed. Therefore, the findings do not directly establish enhanced bioavailability, physiological sleep promotion, or neuroprotection.
- MakaleYalnız künye2026Scopus SJRQ1Impact of hybrid Er2O3 and B4C additions on structural characteristics and experimental gamma-ray transmission behavior of Ni–Co–Fe–Cr–Mo high-entropy alloys
Özkul, İskender; Güler, Ömer; Durmus, Hasan; Camgoz, Berkay; ALMisned, G.; Yaprak, Gunseli; Tekin, H.O.
This study examines how Er2O3 and B4C additions affect the structural, microstructural, mechanical, and gamma-ray attenuation behaviour of Ni–Co–Fe–Cr–Mo high-entropy alloy composites. Five samples, labelled S0–S4, were produced by vacuum arc melting with different single and combined reinforcement contents. Thermodynamic calculations showed that the metallic matrix meets the general conditions expected for solid-solution HEA formation. XRD results indicated that an FCC-based matrix remained dominant in all samples. Reflections related to Er2O3 were identified in the Er2O3-containing compositions, while several weak secondary reflections could not be assigned with certainty because of their low intensity and peak overlap. SEM-EDS analysis confirmed the presence of Er-, O-, B-, and C-containing regions and also revealed local compositional variations within the microstructure. The reinforcement additions produced a clear increase in microhardness, with the highest value of 693 ± 51 HV0.5 obtained for the hybrid-reinforced S3 sample. Gamma-ray attenuation was measured at 276, 302, 356, and 383 keV using a high-purity germanium (HPGe) detector under narrow-beam condition. S4 showed the lowest nominal transmission factor at most energies at its actual sample thickness. However, after correcting for thickness using the Beer-Lambert relationship, S2 generally showed the highest nominal linear attenuation coefficient, while S4 gave closely comparable values at several energies. Some of the differences between samples were within the propagated counting uncertainties and were therefore interpreted with caution. Overall, the results show that the composition giving the highest hardness does not necessarily provide the strongest thickness-normalized gamma-ray attenuation. The attenuation behaviour is influenced by several factors, including reinforcement composition, sample thickness, density, phase distribution, microstructural heterogeneity, and measurement uncertainty. These findings highlight the need to optimize reinforced HEA composites according to the specific mechanical and radiation-related property being targeted.
