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From green hydrogen Hubs to electric vehicle Highways: Crafting feasible sustainable solutions for clean transportation
No full textThe global transportation sector is responsible for nearly a quarter of global carbon emissions, and finding cleaner mobility solutions is essential. By examining how budget allocations for green hydrogen technology influence the adoption of electric vehicles, this research addresses a key sustainability challenge: integrating complementary low-carbon technologies into transportation systems. Despite growing interest in both hydrogen and electric vehicles, little is known about how uneven funding levels shape their joint diffusion across different economic contexts. To fill this gap, we pose the question: How do variations in green hydrogen technology budgets impact electric vehicle stock across ten leading adopters? We address this issue using the Quantile-on-Quantile method, transforming annual R&D and electric vehicle data (2012–2023) into a monthly series, testing for nonlinearity and structural breaks, and estimating asymmetric, quantile-specific effects. The findings reveal that green hydrogen budgets significantly boost electric vehicle adoption in most selected nations, uncover strong positive effects at upper quantiles, and highlight mixed patterns in the UK and France. This asymmetric insight provides policymakers with a nuanced framework for tailoring incentives for hydrogen and electric vehicles. It contributes to the sustainable transport literature by demonstrating the added value of Quantile-on-Quantile analysis in assessing joint technology diffusion
Salmo emireae (Salmoniformes, Salmonidae), a new trout species from the Lake Balık, northeastern Turkey
No full textTrout species of the genus Salmo in Eastern Anatolia offer valuable insights into the evolution and diversity of freshwater fishes in the Caspian Sea basin. In the present study, we describe a new trout species, Salmo emireae sp. nov., from Lake Balık in northeastern Turkey, based on combined morphological and mitochondrial (cytochrome b) data. Phylogenetic analyses using maximum likelihood and Bayesian inference methods revealed that S. emireae belongs to the Danubian lineage and forms a well-supported monophyletic clade, closely related to S. ischchan, S. aestivalis, and S. gegarkuni from Lake Sevan. Moreover, unique morphological traits—by a shorter head, a slenderer caudal peduncle, a shorter maxilla, and a shorter mouth gape—distinguish S. emireae from its congeners. Given its limited distribution and pressure from overfishing, S. emireae may be considered endemic and potentially vulnerable. Our findings highlight the need for further taxonomic and conservation studies on endemic trout species in the region. The study provides a detailed diagnosis, morphometric description, distribution map for the new species, and an extensive phylogeny for genus Salmo, contributing to the growing biodiversity knowledge of Anatolian trout. The new species is endemic to a single, isolated lake that is subject to regular commercial fishing and recent drought-related habitat changes. These pressures, together with its restricted range, make S. emireae potentially vulnerable and of conservation concern
Turkish hazelnut extracts exert anti-proliferative and anti-cancer effects on colorectal cancer HCT-116 cells
No full textThe rising incidence of cancer has demanded the development of new anti-cancer chemical sources. The presence of phenolics in hazelnut cell cultures has led to the development of new and potential pharmacotherapeutic uses. Hazelnut extract has emerged as a promising candidate due to its high phytochemical content. HCT-116 colorectal cancer IC50 cell viability of Palaz and Tombul hazelnut extracts was determined as 400 μg/mL and 200 μg/mL, respectively. Flow cytometry annexin V-fluorescein isothiocyante (FITC) apoptosis detection indicated apoptosis of Tombul hazelnut extract and Palaz hazelnut extract as 23.53% and 17.47%, respectively. The apoptosis result of flow cytometry was also supported at the protein level. Hazelnut extracts resulted in an increased loss of MMP as well. The loss of MMP has significantly increased from an average of 0.61% to 16.17% in Tombul hazelnut extract and to 20.38% in Palaz hazelnut extract. This is further supported by screening MICU1, MICU2, PPAR-γ, PPARGC1A, UCP1, UCP2, and UCP3 gene expressions. Targeting apoptosis pathways, particularly MMP, is an effective strategy for cancer prevention and treatment. Hazelnut extract contains phenolic compounds, which activate these pathways, resulting in enhanced apoptosis in colorectal cancer cells. The phenolic contents of Palaz and Tombul hazelnut extracts were determined as 271.72 ± 5.3 mg gallic acid equivalent (GAE)/100 g sample dry weight (DW) and 85.23 ± 2.2 mg GAE/100 g sample DW, respectively. Further, hazelnut extract may reduce oxidative stress, contributing to its anti-cancer properties. The extracts could be utilized as functional ingredients in foods and nutraceuticals to assist with cancer prevention and treatment
Analytical-to-AI pipeline: Modeling and optimization of entropy generation in pulsating non-Newtonian heat flow
No full textThis study introduces an integrated analytical-to-AI framework for modeling and optimizing entropy generation in pulsating non-Newtonian heat and fluid flow specifically within two basic geometries: circular pipe and plane duct geometries. A semi-analytical model, based on the second law of thermodynamics, is first developed using the perturbation method to evaluate entropy generation under fully developed laminar flow and constant heat flux conditions. The model is validated against existing benchmark solutions, confirming its accuracy. Using this model, a comprehensive dataset is created by varying key dimensionless numbers: Brinkman number ( Br ), power-law index ( n ), pulsation amplitude (ε), and frequency ( F ). Four machine learning (ML) models are then trained to predict entropy generation, among which Gaussian Process Regression (GPR) shows the highest accuracy and is selected as the surrogate ML model for optimization. It is performed using the Grey Wolf Optimization (GWO) algorithm under different flow scenarios. The results indicate that shear-thinning fluids, especially with high amplitude (ε = 0.3) and moderate-to-high frequency pulsation ( F = 60.803 for the circular pipe and F = 53.843 for the plane duct), yield the lowest entropy generation (Nsavg = 1.850 for the circular pipe and Nsavg = 0.911 for the plane duct), while an increase in the power-law index leads to higher Nsavg. The frequency range where entropy generation is significantly affected expands with increasing power-law index. These findings demonstrate the combined effect of fluid rheology and pulsation in reducing entropy generation. Furthermore, they emphasize that the proposed framework offers a reliable and efficient approach for analyzing and improving thermal systems using a combination of analytical modeling, machine learning, and optimization
Identification of potential entomopathogenic bacteria in the culturable bacterial flora of the Brown Marmorated Stink Bug (Halyomorpha halys, Stål, 1885) (Hemiptera: Pentatomidae)
No full textThe Brown Marmorated Stink Bug (Halyomorpha halys) has become a major invasive agricultural pest in Türkiye, particularly threatening hazelnut production in the Black Sea Region. This study aimed to isolate and identify culturable bacterial flora from H. halys populations in Türkiye and assess their potential as biological control agents. A total of nine bacterial isolates were obtained from diseased individuals and identified using morphological, biochemical, and 16 S rRNA gene sequencing analyses. A total of nine bacterial isolates were obtained and identified as belonging to six genera: Bacillus, Staphylococcus, Mammaliicoccus, Enterobacter, Acinetobacter, and Lysinibacillus. Insecticidal bioassays revealed that all isolates exhibited varying levels of pathogenicity against H. halys, with Bacillus thuringiensis (Hh18) causing 100% mortality in nymphs and 66% in adults at 1 × 10⁷ CFU/mL after 10 days. Staphylococcus aureus and Acinetobacter sp. caused 86% mortality in nymphs, while Mammaliicoccus sciuri achieved 53% mortality in adults. These quantitative results provide strong evidence for the entomopathogenic potential of native bacterial isolates against H. halys
Enhancing thermo-aerodynamic performance of solar chimney power plants
No full textRenewable energy technologies, including Solar Chimney Power Plants (SCPP), harness natural resources to produce clean energy. SCPPs use solar energy to heat air, generating an upward flow that drives turbines to produce electricity. This study, conducted at the University of Ouargla, Algeria, explores design improvements to enhance SCPP performance. The study found that a collector opening height of 0.05 m provided the highest efficiency, achieving an air velocity of 5.8 m s−1 and a maximum collector temperature of 68.3 °C, with a temperature difference of 51.2 °C relative to the ambient air. In comparison, opening heights of 0.15 m and 0.20 m resulted in lower airflow velocities of 4.2 m s−1 and 3.8 m s−1, respectively, causing heat loss. The use of a curved junction between the collector and chimney improved airflow, reaching 6.7 m s−1 at the chimney entrance, outperforming straight junctions. Incorporating an air guide further enhanced airflow, with a peak velocity of 6.7 m s−1 for a guide height of 1.0 m. The innovative helical collector design extended the airflow path to 10 m, improving energy output. When combined with an air guide, the helical collector system achieved the highest air velocity of 7.2 m s−1. These findings demonstrate that thoughtful structural enhancements significantly boost SCPP performance
Changing political boundaries in the black sea and fisheries: Turkish-Russian fishing practices in crimea and its surroundings (1774-1917)
No full textThis study aims to examine the transformation of the Black Sea from a "Turkish lake" into an arena of rivalry between the Ottoman Empire and the Russian Empire through the lens of fishing activities, thereby revealing the local-level impacts of this broader geopolitical shift. In the eighteenth and nineteenth centuries, the population policies implemented by Russia along the Crimean coast resulted in the relocation of local communities to inland areas, which in turn weakened the existing fishing culture and reduced production capacity. Although this economic and demographic vacuum was initially filled by Ottoman fishermen from Anatolia, Russia's long-term objective was to develop fishing activities conducted by its own subjects. To this end, the empire pursued scientific research, made targeted investments, and introduced legal regulations to consolidate its economic autonomy in the region. These developments are evaluated comparatively based on archival documents, consular reports, and other primary written sources from the period. The findings indicate that the initial cooperation between Ottoman fishermen and Russian authorities gradually gave way to mounting conflicts over issues such as territorial waters, border violations, citizenship status, taxation practices, and coastal security. This process suggests that the Black Sea was not merely a resource-rich fishing ground but also a fluid and dynamic frontier, where the struggle for influence between the Ottoman Empire and Russia unfolded. In this context, fishermen appear not as passive victims of imperial competition, but as active agents capable of adapting to changing and often challenging circumstances
Pandemic panic and financial predation: the strategic evolution of financial crimes in uncertain times
No full textThe varying impact of pandemic uncertainty significantly influenced the patterns of financial crimes, as economic instability and disrupted oversight systems provided new opportunities for fraud and embezzlement. Conversely, sectors with enhanced digital surveillance saw a notable decrease in such crimes, highlighting the varying effects across different economies. This research assesses the impact of pandemic uncertainty on financial crimes in ten selected economies (the USA, Germany, China, India, Brazil, Australia, South Africa, Japan, the UK, and Russia). Previous works have predominantly used panel data techniques, overlooking the distinct characteristics of various economies. Contrarily, this research employs the Quantile-on-Quantile methodology. It enables the investigation of relationships between variables within each specific country. Consequently, the study offers a comprehensive global perspective, revealing nuanced insights into the unique characteristics of individual economies. The findings show a positive relationship between pandemic-induced uncertainty and financial crimes across various quantiles in most selected economies. Moreover, the study reveals varying trends in these relationships within specific quantiles of the variables in sample countries. These insights accentuate policymakers' need to conduct comprehensive assessments and formulate resilient strategies to monitor shifts in both financial crimes and pandemic uncertainty
The role of docosahexaenoic acid in the development of preeclampsia and perinatal outcomes
No full textBackground/Objectives: Preeclampsia is a leading cause of maternal and perinatal morbidity worldwide, yet its underlying mechanisms remain unclear. Polyunsaturated fatty acids, particularly docosahexaenoic acid (DHA), are essential for placental development and vascular function, but evidence on their role in preeclampsia is inconsistent. This study aimed to compare serum DHA levels between women with preeclampsia and normotensive pregnant women and to examine their association with disease severity and maternal and perinatal outcomes. Methods: A total of 145 pregnant women aged 18–40 years were enrolled, including 47 with newly diagnosed preeclampsia (PE) and 98 normotensive controls. PE was defined according to the ACOG 2019 criteria. Serum DHA levels were measured using ELISA in fasting blood samples collected at the first visit. Results: Maternal serum DHA levels did not differ significantly between preeclampsia and control groups (p = 0.571); they were similar across control, mild PE, and severe PE groups. DHA showed a negative correlation with neutrophil-to-lymphocyte ratio (r = −0.305) and maternal hospitalization duration (r = −0.334). Independent predictors of PE included nulliparity (OR: 4.43), advanced age (OR: 1.14), elevated BMI (OR: 1.29), and low albumin (OR: 0.77). After adjusting for age and BMI, DHA was an independent negative predictor of IUGR (OR: 0.65). Conclusions: DHA levels: Placental and/or fetal DHA metabolism may be impaired in patients with preeclampsia. Although DHA was not associated with the development of PE, it was a negative predictor of IUGR. DHA reduces the length of maternal hospital stay through its anti-inflammatory effect
