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A comparative biochemical characterization of Allium genetic resources of Türkiye
No full textThe present study aimed to determine the variation in onion and garlic genetic resources collected from the Kelkit Valley, a unique biodiversity concerved region in Türkiye. For this purpose, 17 onion genotypes and 12 garlic genotypes were collected from local growers. A total of 9 biochemical analyses (total phenolic matter, total soluble protein, total dry matter, total flavonoid matter, ferric reducing antioxidant power, cupric reducing antioxidant capacity, 2,2-diphenyl-1-picrylhydrazylradical scavenging activity, hydrogen peroxide scavenging capacity and ascorbic acid) were performed on bulb and leaf extracts of all genotypes. According to variance analysis of the biochemical results from the samples, the differences between genotypes for all parameters were found to be significant (p < 0.05). A post-hoc test (Tukey) and multiple means comparison were performed to analyze the results between groups in cases of significant differences. The results indicated that there is a large variation between different genotypes of both species and between both species and organs.</p
Switchable solvent-based liquid phase microextraction of Sudan dyes in food and water samples with HPLC-DAD
No full textIn this study, an environmentally friendly switchable hydrophilicity solvent (SHS) which is a hydrophilic N,N-dimethylbenzylamine carbonate compound in two forms, polar and non-polar, was used in liquid-liquid microextraction (LLME) before HPLC-DAD analysis to separate and preconcentrate Sudan I, Sudan II, Sudan III, and Sudan IV dyes from food and water samples. The optimization of the microextraction process was performed by studying the effects of various parameters such as pH, SHS volume, phase transition triggering agent volume, sonication, and centrifugation times. In this study, where 300 µL SHS was used, LLME total analysis time was performed in 4.5 minutes with high recovery at pH 8.0. The SHS-LLME procedure's preconcentration factor is 50. This SHS-LPME method offers an environmentally friendly option for the extraction of Sudan dyes from food and water samples
Çevre Vergileri, Hava Taşımacılığı ve CO2 Emisyonları İlişkisi: Avrupa Ülkeleri Üzerine Bir Çalışma
No full textHava taşımacılığından kaynaklanan CO2 emisyonları konusu önemli çevresel kaygılar yaratmaya devam etmektedir. Havacılık sektörü büyüdükçe karbon ayak izi de büyümekte ve iklim değişikliğine katkıda bulunmaktadır. Bunu ele almak için hükümetler ve politika yapıcılar hava taşımacılığına çevre vergileri uygulamayı düşünmektedir. Bu vergiler, havayolu şirketlerini daha temiz teknolojilere yatırım yaparak ve verimliliği artırarak emisyonları azaltmaya teşvik etmeyi amaçlamaktadır. Ancak, çevresel sürdürülebilirlik ve ekonomik uygulanabilirlik arasında bir denge bulmak, bu karmaşık ve birbirine bağlı küresel sektörde bir zorluk olmaya devam etmektedir. Bu çalışma, 1995-2021 yılları arasında 25 Avrupa ülkesinde CO2 emisyonları, çevre vergileri, fosil yakıt tüketimi, turizm ve hava taşımacılığı arasındaki ilişkiyi incelemektedir. Korelasyonu tahmin etmek için Panel Vektör Otoregresyon modeli kullanılmaktadır. Sonuçlar, mevcut çevre vergilerinin CO2 emisyonlarını azaltmak için yeterli olmadığını desteklemektedir. Bulgular ayrıca fosil yakıt tüketimi, turizm ve hava taşımacılığının CO2 emisyonlarında artışa yol açtığını göstermektedir. Ayrıca, hava taşımacılığı, turizm, çevre vergileri ve CO2 emisyonları arasında çeşitli nedensellikler bulunmaktadır.The topic of CO2 emissions from air transportation remains a major environmental concern. As the aviation industry expands, so does its carbon footprint, which contributes to climate change. To tackle this issue, policymakers and governments are exploring the possibility of implementing environmental taxes on air transportation. The objective of these taxes is to encourage airlines to invest in cleaner technologies and improve efficiency to reduce emissions. However, achieving a balance between environmental sustainability and economic viability remains a challenge in the complex and interconnected global sector of air transport. This study analyzes the relationship between CO2 emissions, environmental taxes, fossil fuel consumption, tourism, and air transport in 25 European countries from 1995 to 2021. To estimate the correlation, a Panel Vector Autoregression model is used. The results indicate that current environmental taxes are inadequate in reducing CO2 emissions. Additionally, the findings demonstrate that CO2 emissions increase due to fossil fuel consumption, tourism, and air transportation. Furthermore, there are several causal connections between air transportation, tourism, environmental taxes, and CO2 emissions
The Role of Diaphragmatic Ultrasound in Identifying Sarcopenia in COPD Patients: A Cross-Sectional Study
No full textEnterococcus faecalis and E. faecium in dairy production line: Antibiotic resistance profile and virulence characteristics
No full textThis study investigated the prevalence, antimicrobial resistance and virulence of Enterococcus faecalis and E. faecium, in two dairy plants, posing public health risks. Overall, from 219 samples, 42 were contaminated with E. faecium (26/42, 62%) or E. faecalis (16/42, 38%), which confirmed via PCR and BD Phoenix automated system. Antibiotic resistance was found in 48% of the enterococci isolates, with high rates for azithromycin (31% E. faecalis, 27% E. faecium), erythromycin (44% E. faecalis, 27% E. faecium), and tetracycline (19% E. faecalis, 12% E. faecium). ciprofloxacin and vancomycin resistances were rare (below 10% for both). Notably, 25% of the resistant isolates were multidrug-resistant (MDR) with a Multiple Antibiotic Resistance (MAR) index of 0.3. Virulence analysis showed that 69% of 42 isolates harboured at least one esp or efaA, or both genes which are essential for enterococcal pathogenesis, while 67% of isolates produced biofilms. Most antibiotic-resistant isolates (60%) were biofilm producers and harboured associated virulence genes. In conclusion, antibiotic-resistant E. faecalis and E. faecium along the dairy production line might pose potential food safety and public health concerns, due to their presence in biofilm communities, which enhance antibiotic resistance and facilitate horizontal gene transfer
Temporal land use change and its effects on climate in Elmalı basin using GIS and remote sensing
No full textLand use is vital in sustaining human activities, particularly in rapidly urbanizing regions like the Istanbul Metropolitan Area, where large-scale projects such as the Canal Istanbul, Third Airport, and Yavuz Sultan Selim Bridge have significantly impacted land use. These developments have driven population growth, leading to unplanned urbanization and environmental degradation, particularly in watersheds. In this study, the Elmal & imath; Basin, a critical water source on the Anatolian side of Istanbul, was analyzed using Landsat-8 satellite imagery with a spatial resolution of 30 m for multispectral bands, covering the years 2013, 2015, 2018, and 2020. The results reveal a 36% increase in settlement areas, a decline in forest cover, and an increase in surface runoff from 78.76% in 2013 to 80.56% in 2020, mainly due to unplanned construction and climate changes. Temperature trends from 1979 to 2023 show an increase from 14.7 degrees C to 16.1 degrees C, while monthly precipitation anomalies highlight increasing variability in rainfall patterns. Moreover, the frequency distributions of monthly precipitation at the Florya and G & ouml;ztepe stations show that low-intensity precipitation events are expected. In contrast, high-intensity events are rare, signaling drought and flood risks, which underscore the need for effective water management strategies. This study, which investigates the temporal changes in land use and their effects on climate, is crucial for providing preliminary insights that can inform future planning efforts
DFT and molecular docking research on the effects of lichen metabolites
No full textBreast cancer remains a significant public health problem worldwide and requires the investigation of new treatment methods. Lichens, symbiotic organisms rich in bioactive compounds, have emerged as promising sources of natural anticancer agents. This study investigates the anticancer effects of lichen metabolites derived from Xanthoparmelia taractica on breast cancer cell lines MCF-7 and MDA-MB231. High-performance liquid chromatography (HPLC) was used to measure specific lichen acids in the extract; this revealed the presence of Gyrophoric acid (GA), Norstictic acid (NA), Protocetraric acid (PA), Stictic acid (SA), and Usnic acid (UA). Cytotoxicity analysis showed significant reductions in cell viability, particularly in the MDA-MB231 cell line, with IC50 values ranging from 21.67 to 36.71 µg/mL. Molecular docking studies elucidated the interaction mechanisms between these metabolites and target proteins, highlighting NA as the most promising compound with the lowest binding energy (−9.5 kcal/mol) and inhibition constant (0.108755 μM). ADMET analysis of the molecules was then performed. Molecular electrostatic potential (MEP) and HOMO-LUMO analysis provided further information about the reactivity and electron distribution of the compounds. This study has the potential to provide novel therapeutic agents for breast cancer to tackle the increasing resistance to conventional therapies. Lichen metabolites enable the development of effective therapies in targeting aggressive subtypes such as triple-negative breast cancer with limited treatment options. This research highlights the anticancer properties of lichen metabolites and their potential in the development of innovative strategies for breast cancer treatment. The findings offer a promising avenue to address the urgent need for effective therapies in oncology
Antioxidant capacity, biochemical composition, and nutrient content of leaves in two apple species (Malus domestica Borkh. and M. kirghisorum Al. Fed. & Fed.)
No full textA comprehensive performance evaluation of phase change materials for cold energy storage systems
No full textThe increasing need for cooling, particularly air conditioning, is driving a significant rise in building energy consumption. This surge in demand often leads to peak loads, straining power grids and increasing costs. Cold thermal energy storage systems, especially those utilizing phase change materials, offer a promising solution to mitigate these challenges. This study presents a comprehensive investigation and performance assessment of various phase change materials for efficient cold energy storage applications. Phase change materials are considered encapsulated, one of the most common techniques in cold thermal energy storage applications. The primary objective is to develop a comprehensive methodology for the system's design and then identify the most suitable phase change material for better system performance. The research also studies the impact of storage tank porosity, diameter-to-height ratio, and pressure drop on system performance for a 1 MWh cooling capacity. The performance assessment considers all essential power drivers of the practical systems. The findings reveal that water/ice is the most efficient phase change material, requiring the smallest mass and exhibiting the highest overall system COP values by lowering the heat transfer fluid pump and chiller powers. Specifically, it has been determined that water/ice is the most efficient phase change material, requiring the smallest mass quantity of 10.4 tons and demonstrating overall coefficient of performance values ranging from approximately 3.98 to 4.37 for different heat transfer fluid options. This research contributes to the development of sustainable and cost-effective cooling solutions, addressing the growing energy demands of the building sector and promoting a more resilient and efficient energy infrastructure
