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Dynamic modeling of the CNG fast-filling process with a buffer storage system for various natural gas mixtures
No full textCNG, or compressed natural gas, is a clean alternative fuel for transport vehicles. CNG offers several advantages, including as lower expenses, less emissions, and simpler vehicle maintenance. Natural gas vehicles, or NGVs, are vehicles equipped with high-pressure tanks that hold compressed natural gas (CNG). This work presents a mathematical simulation model to investigate the fast-filling procedure for buffer storage at CNG refueling stations. To represent the process, the conservation equations of mass, momentum, and energy are discretized and solved in an iterative manner. Heat transfer between the vehicle tank and the environment prevents the temperature rise so more gas mass could be filled to the tank. The heavier gases in the gas mixture cause the mass to be higher. This can be a disadvantage for fuel quality, but it seems to be useful for the filling process
The mediating role of emotion dysregulation (difficulties in emotion regulation) in the relationship between cyber dating abuse and negative affect
No full textBu çalışmada, siber flört istismarı ile negatif duygu durumu arasındaki ilişkide duygu düzenleme güçlüğünün aracılık rolü incelenmiştir. Araştırma kapsamında 526 katılımcıdan toplanan veriler, Siber Flört İstismarı Ölçeği, Pozitif ve Negatif Duygu Ölçeği ve Duygu Düzenleme Ölçeği-Kısa Formu kullanılarak elde edilmiş ve SPSS 25.0 programı ile analiz edilmiştir. Negatif duygu durumu ile maruz kalınan ve uygulanan siber flört istismarı arasında pozitif yönlü anlamlı bir ilişki bulunmuştur. Siber flört istismarı arttıkça bireylerin negatif duygu durumları da yükselmektedir. Aynı zamanda, duygu düzenleme güçlüğü ile negatif duygu durumu arasında da pozitif yönlü anlamlı bir ilişki tespit edilmiştir. Aracılık analizi sonuçlarına göre, duygu düzenleme güçlüğü, siber flört istismarının negatif duygu durumu üzerindeki etkisinde kısmi bir aracılık rolü üstlenmektedir. Bu bulgu, siber flört istismarına maruz kalmanın ve bunu uygulamanın bireylerin duygularını düzenlemede zorlanmasına ve negatif duygulanım düzeylerinin artmasına yol açtığını ortaya koymaktadır. Bu çalışmanın sonuçları, siber flört istismarı ile psikolojik iyi oluş arasındaki ilişkiyi anlamak açısından önemli olup, özellikle duygu düzenleme becerilerini geliştirmeye yönelik müdahalelerin bu alanda faydalı olabileceğini göstermektedir.In this study, the mediating role of emotion regulation difficulties in the relationship between cyber dating abuse and negative affect was examined. Data were collected from 526 participants using the Cyber Dating Abuse Scale, the Positive and Negative Affect Schedule (PANAS), and the Difficulties in Emotion Regulation Scale–Short Form (DERS-SF), and analyzed with SPSS 25.0. The findings revealed a significant and positive relationship between negative affect and both victimization and perpetration of cyber dating abuse. As levels of cyber dating abuse increased, individuals’ negative affect also increased Additionally, a significant positive relationship was found between emotion regulation difficulties and negative affect. According to the mediation analysis results, emotion regulation difficulties partially mediated the effect of cyber dating abuse on negative affect. This suggests that experiencing or perpetrating cyber dating abuse may impair individuals’ ability to regulate emotions, thereby increasing their levels of negative affect. Overall, the findings highlight the importance of understanding the connection between cyber dating abuse and psychological well-being, suggesting that interventions aimed at improving emotion regulation skills may be beneficial in mitigating the negative emotional consequences associated with cyber dating abuse
Determination of the cecal microbiota profile of anadolu-t broiler breeder chickens using 16s metagenomic sequencing
No full textThe gut microbiota has significant effects on the performance, health status, and immune systems of chickens. The complex microbial community structure begins to form after chicks hatch with the intake of feed, water, and air into the digestive system. Disrupting the balance of this system can lead to the proliferation of pathogenic microorganisms. Until recently, studies on microbiota relied on traditional microbiological techniques that cultured only a small fraction of the microbial diversity. However, significant advancements in DNA sequencing and bioinformatics have enabled the identification of diverse bacterial populations in environmental samples. In this study, a total of 2000 broiler chickens from 5 pure lines bred since 2015 at the Eskisehir Gecit Kusag & imath; Agricultural Research Institute's Broiler Chicken Breeding and Improvement Department were used. A total of 100 cecal fecal samples were randomly collected, with 20 samples from each pure line at 3, 8, 15, 25, and 32 weeks of age. DNA was isolated from these samples and the diversity of the bacterial flora in the cecum was investigated using 16S rDNA gene sequencing. Across all samples, the most abundant genus identified was Bacteroides, with an average relative abundance of 9.125%, while Ruminococcus was the least abundant genus, with an average relative abundance of 0.005%. A total of 306 different species were identified. The most abundant species detected was Akkermansia muciniphila, with an average relative abundance of 1.4 +/- 8.31%. This study is the first to examine the cecum microbiota of Anadolu-T pure lines, a local genotype bred in T & uuml;rkiye, on a line-by-line and temporal basis.Tarım ve Hayvancılık Bakanlığı Tarım ve Ormancılık Bakanlığı - Türkiye
Tarım Araştırma ve Politikaları Genel Müdürlüğü (TAGEM) - Türkiye Cumhuriyeti Tarım ve Ormancılık Bakanlığı TAGEM/HAYSD//22/A4/P4617
Enhancing the analysis of rheological behavior in clinker-aided cementitious systems through large language model-based synthetic data generation
No full textThis study investigates the parameters influencing the compatibility between cement and polycarboxylate ether (PCE) admixtures in cements produced with various types and dosages of grinding aids (GAs). A total of 29 cement types (including a control) were prepared using seven different GAs at four dosage levels, and 87 paste mixtures were produced with three PCE dosages. Rheological behavior was evaluated via the Herschel-Bulkley model, focusing on dynamic yield stress (DYS) and viscosity. The data were modeled using CNN, Random Forest (RF), and Neural Classification and Regression Tree (NCART), and each model was enhanced with synthetic data generated by Large Language Models (LLMs), resulting in CNN-LLM, RF-LLM, and NCART-LLM variants. All six variants were evaluated using R-squared, Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Logcosh. This study is among the first to use LLMs for synthetic data augmentation. It augmented the experimental dataset synthetically and analyzed the effects on the study results. Among the baseline methods, NCART achieved the best performance for both viscosity (MAE = 1.04, RMSE = 1.33, R2 = 0.84, Logcosh = 0.57) and DYS (MAE = 8.73, RMSE = 11.50, R2 = 0.77, Logcosh = 8.09). Among baseline models, NCART performed best, while LLM augmentation significantly improved all models' predictive accuracy. It was also observed that cements produced with GA exhibited higher DYS and viscosity than the control, likely due to finer particle size distribution. Overall, the study highlights the potential of LLM-based synthetic augmentation in modeling cement admixture compatibility
Eef2k is a poor prognostic factor and novel molecular target in pancreatic cancer: Regulating tumor growth and progression via the tumor microenvironment
No full textPancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, with an average survival time of only six months following diagnosis, even with currently available therapies. Thus, PDAC represents a significant therapeutic challenge, necessitating a deeper understanding of its biology and tumor microenvironment (TME) to develop more effective treatments and improve patient outcomes. Here, we report that the expression of Eukaryotic Elongation Factor-2 Kinase (eEF2K) is associated with shorter patient survival and demonstrate that eEF2K signaling is critical for the PDAC tumor growth and regulated by the TME. Furthermore, in vivo targeted genetic inhibition of eEF2K suppressed tumor growth in two different PDAC mouse models, reduced tumor-associated macrophages (TAMs), and induced marked apoptosis in tumor tissues without any signs of toxicity. Our data suggest that eEF2K knockdown diminishes the activity of the AXL receptor tyrosine kinase and reduces the expression of macrophage-derived factors, such as Monocyte Chemoattractant Protein-1 (MCP1), along with the Gas6/AXL signaling pathway in PDAC cells. Additionally, analysis of the NCI-TCGA PDAC patient database further showed that eEF2K expression, in the presence of TAM markers, correlates with even shorter patient survival. TAM-released factors, such as MCP1, Gas6, and exosomes, induce eEF2K expression in PDAC cells, as well as the activity of AXL, SRC, VEGF, Snail, and MMP2, contributing to epithelial-to-mesenchymal transition (EMT), invasion, metastasis, and angiogenesis. In conclusion, our findings reveal for the first time that eEF2K is a critical oncogenic driver of PDAC tumor growth and thus targeting eEF2K represents a promising and novel therapeutic strategy for PDAC.UT | University of Texas MD Anderson Cancer Center (MD Anderson)MD Anderson Cancer Center's Institutional Bridge Funding
2214 AInternational Doctoral Research Fellowship Programme, Turke
Ardl bound testing approach for a green low-carbon circular economy in turkey
No full textThis study analyzes Turkey's development toward a green economy between 1990 and 2022 within the framework of certain green economic indicators. The data consist of secondary data from the official databases of the World Bank and the Turkish Statistical Institute (TURKSTAT). In the study, the total amount of carbon emissions was chosen as an indicator of green growth, while gross domestic product per capita (GDP) represents economic growth, domestic loans granted by banks to the private sector (as a percentage of GDP) and foreign direct investment represent financial development, and electricity generation represents pollution. To determine whether the variables are cointegrated and to determine the direction and strength of the relationship between the variables, the ARDL bounds test and the FMOLS and DOLS long-run estimators were used. Finally, Toda Yamamoto (TY)-Granger tests were performed to determine causality. The long-term relationship between the variables was confirmed by the results of the ARDL bounds test. The error correction coefficient (CointEq(-1)) was estimated to be statistically significant and negative (-0.757) when the short-term analysis was performed. This result shows that the short-term imbalances will be corrected in less than a year, and the system will approach the long-term equilibrium. In the long-term analysis of the model, all variables selected to explain the dependent variable were found to have a statistically significant impact on the dependent variable. The GDP per capita variable, the indicator of economic growth, has a negative effect on the dependent variable, while the other independent variables have a positive effect. The results of the causality analysis indicate that the dependent variable carbon emissions (CO2) has a unidirectional causality relationship with domestic credit provided to the private sector by banks (DC), which represents financial development, and with total electricity production (EP), which serves as an indicator of pollutants
Production of woven aramid based protective equipment and improving its ballistic performance
No full textIn this study, various ballistic armour materials were designed using aramid fibre fabrics. Initially, soft armour designs were tested according to NIJ 0101.03 Level II standards across different configurations. However, the trauma depths observed in these tests exceeded the acceptable limits defined by the standards. To address this, a hard armour design was developed by incorporating reinforcement elements, such as silicon dioxide, graphene nanoplatelets, multi-walled carbon nanotubes, and Ti3AlC2 (MAX phases) powders, into the aramid fabrics. These reinforcements were mixed with vinylester resin at concentrations of 3%, 5%, and 10%. The resulting mixture was impregnated into 25-layer aramid fabrics arranged in different orientations to produce composite plates. Ballistic tests were conducted on these plates in accordance with NIJ 0101.03 Level III standards. The tests revealed that the hybrid composite structure absorbed a substantial amount of energy, particularly in the central region of the plates. Plates reinforced with graphene nanoplatelets exhibited penetration under ballistic testing, but an improvement in ballistic performance was observed as the reinforcement density increased. Among all reinforcements, the best ballistic performance was achieved with Ti3AlC2(MAX phase) additives. As a result, prototype designs with enhanced protection levels and improved ballistic performance were successfully produced
FDG Extravasation in PET/CT imaging: A visual grading approach based on clinical observations
No full textPurpose This study aims to introduce a practical, visually based grading system for FDG extravasation in PET/CT imaging and to investigate its impact on semi-quantitative SUV measurements in reference regions. The objective is not only to quantify the effect but also to provide a framework for guiding clinical interpretation and reporting. Methods A total of 235 oncologic PET/CT scans were retrospectively analysed. Patients were categorised into four groups based on extravasation severity: Grade 0 (no extravasation), Grade 1 (minimal), Grade 2 (moderate), and Grade 3 (severe). A visual grading system was developed and applied to classify image quality degradation. Mean SUVmax and SUVmean values were recorded from liver and mediastinal blood pool regions. Statistical comparisons were conducted using ANOVA and post hoc testing. Results FDG extravasation was observed in 75 patients (31.9%). Among the 75 patients with extravasation, 43 were Grade 1 and 26 were Grade 2. Statistically significant increases were found in both liver and mediastinal SUV values in patients with Grade 1 and 2 extravasation compared to Grade 0 (p < 0.001 for all). For example, Liver SUVmax increased from 3.13 +/- 0.44 (Grade 0) to 3.58 +/- 0.50 (Grade 1), and MedSUVmean increased from 1.80 +/- 0.31 (Grade 0) to 2.17 +/- 0.40 (Grade 2), representing up to a 20.6% difference. Grade 3 cases did not show consistent trends. Conclusion Low-to-moderate FDG extravasation can significantly alter reference SUV values. Incorporating extravasation grading into clinical reporting or normalising reference SUV values may enhance diagnostic consistency and minimise the need for repeat imaging
The creative problem-solving skills test: Development and initial validation
No full textThis study aimed to develop and validate the Creative Problem-Solving Skills Test (CPSS-T), grounded in Torrance's creativity theory, to assess these skills in university students. The CPSS-T consists of five open-ended question types, each designed to measure different aspects of creative problem-solving: Alternative Use, Hypothetical Scenario, Problem-Solving, Visual Interpretation, and Future Design. Content validity was ensured through expert feedback from six specialists in educational psychology and creativity. The test was administered to a sample of 1007 university students to conduct its validity and reliability analyses. Confirmatory factor analysis (CFA) indicated adequate model fit, supporting the construct validity of the test in alignment with Torrance's theoretical framework. The CPSS-T also demonstrated strong convergent and discriminant validity. Reliability analysis revealed high internal consistency, with Cronbach's alpha and Omega values as follows: Alternative Use (alpha = 0.87, omega = 0.87), Hypothetical Scenario (alpha = 0.85, omega = 0.85), Problem-Solving (alpha = 0.90, omega = 0.91), Visual Interpretation (alpha = 0.74, omega = 0.74), Future Design (alpha = 0.67, omega = 0.67), and the overall test (alpha = 0.93, omega = 0.85). Item-total correlations ranged from 0.511 to 0.812, indicating a strong alignment of the items with the overall test construct. Additionally, the CPSS-T showed significant differences between the upper and lower groups for all items, demonstrating robust discriminatory power at the item level. Criterion-related validity was assessed using the Scientific Creativity Test, revealing significant positive correlations (r = 0.62, p < 0.01), further establishing the CPSS-T as a reliable and valid tool for measuring creative problem-solving skills in university students. These findings suggest that the CPSS-T, supported by Torrance's creativity theory, is a psychometrically sound instrument that educators can use to evaluate and foster creative problem-solving skills in students
A flap that has a philosophy and requires courage to do: Abbe flap
No full textThe Abbe flap is a valuable reconstructive option for secondary deformities of the upper lip following cleft lip repair. In this report, the author present four cases successfully treated with the Abbe flap, demonstrating its reliability and aesthetic outcomes. Each procedure was performed under local anesthesia, utilizing a flap based on the left labial artery. The technique proved effective in addressing whistling deformity, philtrum loss, and upper lip retraction. Even surgeons without prior experience in this flap can achieve functional and cosmetic success when the indication is correct. Despite the limited number of cases, our experience supports the use of the Abbe flap in selected patients, reinforcing its value in modern reconstructive surgery