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Green-synthesized Co@VHE nanocatalyst from Verbascum insulare for enhanced hydrogen generation and biological applications
No full textIn this study, a novel multifunctional material was synthesized by decorating the hydrothermal extract obtained from Verbascum insulare Boiss. & Heldr (VHE) with metallic cobalt nanoclusters (Co@VHE) via in situ reduction using sodium borohydride (NaBH4). The material was first evaluated for its biological activity, including antimicrobial and antioxidant properties. While VHE exhibited antifungal activity only against Y. lipolytica, Co@VHE demonstrated broad-spectrum antimicrobial activity, with the highest zone of inhibition against B. subtilis (26.67 ± 1.16 mm). Co@VHE also exhibited superior antioxidant capacity, showing the strongest DPPH radical scavenging activity (IC50: 4.30). LC-MS/MS analysis confirmed the presence of quinic acid and protocatechuic acid in Vrb-1, along with 17 phenolic compounds in VHE. Additionally, Co@VHE's catalytic performance was evaluated for hydrogen generation through sodium borohydride (NaBH4) hydrolysis. Under optimal conditions (7.5 % NaOH, 15 mg catalyst, 3 % NaBH4), a successful hydrogen generation rate of 36,624 mL g−1 min−1 was achieved. Kinetic and reusability studies further demonstrated the material's high efficiency, moderate activation energy (55 kJ mol−1), and excellent stability over six cycles. Comparative analysis revealed that Co@VHE outperformed several previously reported synthetic cobalt-based catalysts. This work not only introduces V. insulare extract as an effective and eco-friendly catalyst support for the first time, but also highlights its multifunctional potential in both biomedical and energy applications. © 2025 Elsevier B.V., All rights reserved
Impact of exposure to extremely low-frequency electromagnetic fields prior to application of X-rays on the viability of cancerous and healthy cells
No full textThe purpose of this study is to examine the effect of exposing healthy and cancerous cells to extremely low-frequency electromagnetic fields (ELF-EMFs) before the application of ionized X-rays on the viability of the cells. The study was performed on a cancerous (U2OS, osteosarcoma) and a healthy (L-929, fibroblast) cell line. Cells were subjected to different treatment conditions such as 0.6 mT (mT) EMF (EMF1), 1.1 mT EMF (EMF2), 60 kV-X ray (X-ray), EMF1+X-ray (0.6 mT EMF applied before X-ray) and EMF2+X-ray (1.1 mT EMF applied before X-ray). The effects of these applications on cell viability were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. Our findings showed that pre-exposure to ELF-EMF significantly increased in cell viability of both cell lines compared to X-ray alone (p < 0.05). However, it was observed that the cell viability percentage of L-929 cells was higher compared to U2OS cells in EMF1, X-ray and EMF2+X-ray groups (p < 0.05). The outcomes of this study suggest a potential protective effect, as indicated by increased resistance to ionizing X-rays in U2OS and L-929 cells pre-exposed to ELF-EMF radiation
Impact of hydrogen-rich-oxygenated ethyl acetate usage as a dual fuel in diesel engines on combustion stability and exhaust emissions under varying EGR rates
No full textDiesel engines, due to their reliance on petroleum-derived fuels for power generation, not only emit high levels of nitrogen oxides and smoke but also contribute significantly to greenhouse gas emissions that drive climate change. Therefore, the use of alternative fuels has become essential to reduce dependency on petroleum-based fuels in these engines. Oxygenated fuels can be effective in minimizing emissions. In this study, ethyl acetate-which is rich in hydrogen and oxygen and considered a potential hydrogen carrier-is used in dual-fuel mode to improve combustion performance and reduce exhaust emissions. Experimentally, the effects of different exhaust gas recirculation rates and injection durations on the combustion and emission characteristics of a compression-ignition engine operating in a diesel-ethyl acetate dual-fuel mode are investigated. The exhaust gas recirculation rates vary as 0 %, 5 %, 10 %, and 20 %, while the ethyl acetate injection duration changes as 1 ms, 2 ms, and 3 ms. Additionally, experiments are conducted at different engine loads (5 kg, 10 kg, 15 kg, and 20 kg) and a constant engine speed of 1800 rpm. The results indicate that increasing the ethyl acetate injection duration reduces the maximum pressure at low loads but increases it at high loads. Moreover, the use of ethyl acetate increases the ignition delay by approximately 11 % and raises the cycle-to-cycle variation to around 23 %. Regarding emissions, increases in injection duration and exhaust gas recirculation rate reduce nitrogen oxides emissions by an average of approximately 39 % and smoke emissions by an average of around 75 %
Arazi Kullaniminin Cografi Bilgi Sistemleri (CBS) ile Haritalanmasi ve Analizi: Van Sehri Örnegi
No full textBu çalismada, Van merkez ilçeleri ve bunlarin sehir merkezi ile yakin çevresinin alindigi arazi kullanim durumunun analizi amaçlanmistir. Çalismada Cografi Bilgi Sistemleri (CBS) ile Corin haritalarinin manuel çizimi ve sayisallastirma yöntemiyle bazi haritalar olusturulurken, diger bazi haritalar ise uzaktan algilama ve kontrollü siniflandirma metoduyla yapilmistir. Van sehrinin ekonomik, sosyal ve kültürel yönleriyle gelismesi ilin kirsal yerlesmelerinden ve çevre illerden göç almasina neden olmustur. Bu durum arazi kullanimini etkilemistir. Sehirde, 1990, 2010 ve 2024 yillarindaki arazi kullaniminda degisme oldugu görülmüs ve en önemli degisimin tarim arazileri, çiplak alan ve yerlesme alanlarinda oldugu gözlemlenmistir. 1990 yilinda sehir merkezinde tarim alani (%72), yerlesim alani (%11) iken 2024 yilinda tarim alani (%62)’ye düsmüs, yerlesim alani ise (%27)’ye yükselmistir. Yerlesmelerin daha çok ovada kurulmasi tarimsal arazilerin yok olmasina neden olmakta ve yapilasmaya uygun olmayan ovada depremden kaynakli riskleri arttirmaktadir. 2011 yilinda yasanan Van Depremi’nden sonra yeni yerlesim yerleri TOKI konut uygulamalariyla daha çok çiplak alan niteliginde olan ve daha saglam olan arazilere kaydirilmistir. Ancak depremin unutulmasiyla birlikte tekrar ovadaki tarim arazileri üzerinde yapilasma hiz kazanmistir. Bu arastirma arazi kullaniminda yasanan birtakim sorunlarin irdelenmesi ve yapilasmaya uygun olmayan arazilerin amaci disinda kullanilmasinin gelecekte sorunlari daha da büyütebileceginin vurgulanmasi bakimindan önemlidir
Novel 1-morpholine-3-substituted triazol-5-ones: Synthesis and multi-biological evaluation on HepG2 and U87 cells with SAR and DFT studies
No full textThe biologically active novel 1-morpholine-3-substitue-4-(4-phenylacetoxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 4(a-f) were successfully synthesized and structurally characterized by 1H /13C NMR, and FT-IR spectroscopy. Concentration ranges of 31.25, 62.5, 125, 250, and 500 µg/mL were applied to determine the anti-cancer properties of compund. Significant results were obtained against the human hepatoma cells HepG2 and human glioblastoma cell line U87. Antioxidant activities were assessed in vitro using DPPH radical scavenging and metal chelation assays and it was seen that compounds 4(a-f) had metal chelating properties. Furthermore, the enzyme inhibitory effect of compounds on α-amylase (α-Amy), α-glucosidase (α-Gly), glutathione S-transferase (GST), acetylcholinesterase (AChE) enzymes were studied. IC50 values were calculated in different ranges. The antimicrobial properties were investigated using the Agar-well diffusion technique. The compounds had antimicrobial activity against 5 bacteria except Escherichia coli, and especially the inhibition zone diameter of compound 4e against Bacillus cereus was found to be the highest with a measurement of 24 mm. Complementary density functional theory (DFT) calculations and structure-activity relationship (SAR) analyses were performed to provide insights into the molecular properties and biological activities of the synthesized Mannich bases. © 2025 Elsevier B.V., All rights reserved
Investigating the Effect of Different Types of Vinegar on Echinococcus granulosus Protoscolexes
No full textBackground and objectives: Echinococcus granulosus is one of the most common parasitic diseases worldwide. Numerous scientific studies have examined the effects of vinegar on foodborne parasitic diseases. In our research, we aimed to investigate the effect of different vinegar varieties (fig, strawberry, grape, pomegranate, apple, rose, medlar, and hawthorn vinegar) on Echinococcus granulosus protoscolex. Methods: The study was carried out on live protoscolex isolated from cystic organs obtained from regional slaughterhouses, which were used as study material to determine the scolicidal effects of eight different types of natural vinegar. Solutions of 1%, 3%, 5%, and 10% concentrations were prepared for each vinegar type, and their effects on live E. granulosus protoscolexes were monitored according to timing (0, 60, 120, 180, and 240. min) using a computer-aided microscope with camera and software. Results: Based on time and concentration, fig (74.16±4.24%) and strawberry (65.5±2.39%) vinegar were found to have the highest scolicidal effect. This was followed by grape (65.56±12.31%), pomegranate (64.08±3.15%), apple (54.34±2.62%), and rose (47.79±5.28%) vinegar, respectively. On the other hand, medlar (41.15±4.54%) and hawthorn (24.65±1.8%) vinegars were found to have the lowest killing rates for E. granulosus protoscolexes. Conclusions: This research highlights the potential of various vinegars as scolicidal agents and suggests further studies to understand the mechanism behind their effectiveness, which could significantly contribute to medical and parasitological applications. © 2025. Open access
Thermodynamic, thermoeconomic, and exergoeconomic analysis of a UAV two stroke engine fueled with gasoline-octanol and gasoline-hexanol blends
No full textIn recent years, as the use of Unmanned Aerial Vehicle (UAV) engines has increased in various application areas such as military fields, defense, emergencies, and mapping, the use of these engines with fossil-based fuels has raised environmental concerns. The addition of heavy alcohols such as octanol and hexanol, which have high energy densities, to the fossil-based fuels used may help reduce environmental concerns and contribute to performance improvement. In this study, the performance, emissions, thermodynamic, thermoeconomic, and exergoeconomic analysis of a two-stroke engine operating with gasoline-octanol and gasoline-hexanol fuels in a UAV is conducted. There are no studies in the literature that examine the energy, exergy, thermoeconomic, and exergoeconomic aspects of a two-stroke UAV engine operating with gasoline-octanol and gasoline-hexanol fuel mixtures. The aim of this study is to understand the performance and emission characteristics of used heavy alcohols such as octanol and hexanol in a two-stroke UAV engine, and to examine them from a thermodynamic perspective. The experiments are carried out at different shaft speed ranges (3250, 3750, 4500, 5250, and 6250 rpm). Additionally, seven different fuels are used in the experiments: gasoline, gasoline-octanol mixtures (volumetrically 10 %, 20 %, and 30 %), and gasoline-hexanol mixtures (volumetrically 10 %, 20 %, and 30 %). The results show that increasing the octanol content in gasoline to 30 % (OC30) reduces the specific fuel consumption (SFC) by up to 5.5 % (at 6250 shaft speed), while increasing the hexanol content to 30 % (HX30) increases it by 6 % (at 5250 shaft speed). CO emissions decrease by an average of 5.3 % and 9.2 % with OC30 and HX30 fuels, respectively (both at 6250 shaft speed), while CO2 emissions increase by an average of 3 % and 10 % with OC30 and HX30 fuels, respectively. With OC30 fuel, the exergetic destruction decreases by an average of 6 % compared to gasoline, while with HX30 fuel, it increases by an average of 3.3 %. OC30 increases the exergetic efficiency by an average of 5.4 % compared to gasoline, whereas HX30 decreases it by 2.9 %
Investigation of Plastic Ball Bearing Production by Additive Manufacturing
No full textThe aim of this study is to understand whether 3D-produced plastic bearings can replace those produced by plastic injection. First, bearings are produced with SLA and FDM and manufactured with these machines to determine which one is more suitable for bearing production. Then, four different resin types are developed for the inner and outer rings of 6205 polymer hybrid ball bearings with SLA. The findings showed that bearings produced with low elongation resins are not suitable for applications involving loads, as they are broken and fragmented during the tight-fit assembly. In addition, bearings produced with high-viscosity resins failed faster with increased wear and quantity of material during the operating period. These results show that manufacturing and material constraints increase when applying SLA to loading solutions. Nonetheless, the study shows that additive manufacturing has the possibility of specialized, low-volume bearing applications where complicated geometries and quick prototyping are required, provided that resin selection and process modifications are addressed.Gazi University Scientific Research Projects Unit [06/2018-08]Gazi University Scientific Research Projects Unit funded the presented study with Grant No. 06/2018-08
Benzothiophene semiconductor polymer design by machine learning with low exciton binding energy: A vast chemical space generation for new structures
No full textThe development of new organic semiconductors with low exciton binding energies (Eb) is crucial for improving the efficiency of organic photovoltaic (PV) devices. Here, we report the generation of a chemical space of benzothiophene (BDT)-based organic semiconductors with lowest Eb energies using machine learning (ML). Our study involves the design of over 500 organic semiconductor structures with low Eb energies and their synthetic accessibility scores. For this, we collect 1061 BDT based compounds from literature, calculated their Eb energies, and predicted them using ML with Random Forest (RF) regression, yielding the best results. Our analysis, using SHAP values, reveals that heavy atoms are the main factors in lowering Eb values. Furthermore, we tested new organic chromophore structures, which showed an efficient shift of their molecular charges. The UV-Vis spectra of these structures exhibits a redshift in the range of 358-667 nm, while their open-circuit voltage (Voc) and lightharvesting efficiency (LHE) ranges from 1.64 to 1.954 V and 52-91 %, respectively. Current study provides a valuable chemical space for the development of new organic semiconductors with improved efficiency.Taif University, Saudi Arabia [TU-DSPP-2024-76]Funding This research was funded by Taif University, Saudi Arabia, Project No. (TU-DSPP-2024-76)
Promising Antidepressant Potential: The Role of Lactobacillus rhamnosus GG in Mental Health and Stress Response
Full text linkChronic stress is linked to changes in brain physiology and functioning, affects the central nervous system (CNS), and causes psychiatric diseases such as depression and anxiety. In this study, antidepressant effects of the probiotic bacterium Lactobacillus rhamnosus GG (ATCC 53103) (LGG) (15 x 10(8) cfu/ml/day) on the mechanisms playing a role in the pathophysiology of depression were investigated, and the results were compared with the effects of bupropion (20 mg/kg/day) and venlafaxine (20 mg/kg/day). A total of 56 male Wistar Albino rats were used in control, stress, bupropion, venlafaxine, LGG, bupropion + stress, venlafaxine + stress, LGG + stress groups, n = 7 each. Changes in the body weight of the rats during the experiment were determined by weight measurement. Gene expression levels were determined by the RT-PCR method. Four different behavioral tests were performed to evaluate depressive behaviors (sucrose preference test, three-chamber sociability test (social interaction test), elevated plus maze test, forced swim test). LGG treatment was effective in reducing depressive-like behaviors, increased BDNF level, 5-HT1A, DRD1, ADRA-2A, GABA-A alpha 1, CNR1 expression levels in the hippocampus and NOD1 receptor expression level in the small intestine (p < 0.05), and also decreased neurodegeneration level, glial cell activity, and intestinal permeability in depressed rats. As a result, it was revealed in this study for the first time that the LGG probiotic bacterium has antidepressant properties and was found to be more effective than the antidepressant drugs bupropion and venlafaxine. Our results suggest that LGG is a potential psychobiotic bacterium and can be useful to treat depression. It may be an effective and useful option in combating depression.Istanbul Aydimath;n University [2022-9-32-13]; Sakarya University Scientific Research Projects UnitI would like to thank all participants for their contribution to the study. This study was supported by Sakarya University Scientific Research Projects Unit (Project No: 2022-9-32-13)