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REMEDIATION OF NAVY BLUE RX DYE USING BIOLOGICAL AND ADVANCED OXIDATION PROCESS
No full textSynthetic dyes used in the textile industry are causing worldwide concern due to their harmful impact on the environment. In this study, microorganisms capable of decolourizing Navy Blue RX dye were isolated from textile effluent samples and identified using 16S rRNA sequencing. The effects of temperature, pH, initial dye concentrations and mechanical agitation on the dye decolourization ability of individual organisms and their consortia were examined. For improved storage, stability and utility, the organisms were inoculated and incubated with solid substrates - rice flour and compost, and dried to obtain a powdered formulation. Treatment with only a microbial formulation requires a longer time and does not result in complete dye remediation. Therefore, advanced oxidation process, such as the Fenton process and ozonation, was combined with microbial treatment. The effect of different treatment methods and their combinations was analysed by checking the percentage of decolourization using a UV spectrophotometer. Analysis of control and treated samples by gas chromatography-mass spectrometry confirmed the degradation of the parent dye. According to this study, ozonation combined with microbial treatment results in about 98 % decolourization of Navy Blue RX dye
Optimization of the traveling salesman problem through a genetic algorithm guided by self-organizing maps
No full textOptimization is a fundamental process for achieving objectives, exemplified by the Traveling Salesman Problem (TSP), which minimizes resource consumption. This study focuses on optimizing travel routes to reduce fuel costs and maximize tourist visits through efficient time management. We employ a genetic algorithm (GA), a powerful optimization technique, to determine routes. A key challenge in GAs is premature convergence, which can prevent optimal solutions. To address this, we introduce a novel approach integrating Self-Organizing Maps with GAs, specifically through a new selection operator designed to enhance GA performance. An application was developed using real-world coordinates of Pakistani cities. Simulation results demonstrate that our proposed method significantly outperforms existing selection operators in terms of final best distance, average best distance, standard deviation, and computational time. Field validation further confirmed an 18.3% distance reduction and 4.53 million in annual savings in a logistics case study
CAN GENAI BOOST STUDENT ACADEMIC PERFORMANCE: EXAMINING THE ROLE OF AI QUALITY
No full textGenerative Artificial Inteligence (GenAI) tools are becoming increasingly interesting and useful for the student population in higher education (HE). The rate of adoption of GenAI tools at the population level has surpassed all previous technologies in history. The use and adoption of GenAI tools in higher education represents a critical area of future research with profound scientific and practical implications. This new technology is characterized by significant impact on productivity so it becomes important to explore the way that it impacts student work habits and academic results. This paper contributes to the growing body of research on the application of GenAI tools in higher education. It builds on previous research focused on the application of new technologies. The starting point of the paper is the measurement scales necessary to assess the use of GenAI tools in the context of higher education. The primary goal of this paper is to investigate the role of GenAI quality in the dissemination process of GenAI tools primarily through measuring the adoption and use of GenAI. Additionally, the paper addresses the impact of adoption and use of GenAI on student academic performance. The research was conducted among students of a Croatian higher education institution during the winter semester of 2024, and approximately 340 responses were collected. Structural equation modeling (SEM) analysis was used to test the proposed hypotheses. The results of the study confirm that GenAI quality has a significant and positive effect on GenAI use and GenAI adoption. Furthermore, both GenAI adoption and GenAI use have a significant and positive impact on students' academic performance in higher education. The results of the study highlight the importance of GenAI quality in shaping students' experiences with GenAI tools and their broader educational outcomes
DIGITALIZATION OF SMALL AND MEDIUM-SIZED ENTERPRISES IN BULGARIA – A FACTOR FOR THEIR COMPETITIVENESS
No full textDigitalization is a key factor for improving the competitiveness, effectiveness, and sustainability of small- and medium-sized enterprises (SMEs) in Bulgaria. With ever-changing technology, evolving consumer expectations, and increased global competition, SMEs have recognized the use of digital tools has become essential for their growth. This study reveals initial information regarding digitalization implications on Bulgarian SMEs in terms of business transformation or business model innovation in the early stages of the digitalization journey, and highlights the main challenges and opportunities for these businesses in the process of digitalization. Digitalization provides various opportunities for SMEs like access to markets through online sales platforms and/or e-commerce with lower transaction costs and increased access to customers. Cloud services and business process management systems help organizations be more productive internally so they can respond well to the ever-changing landscape of the market. Digital tools engage in innovation, offering better ways to analyze the market, understand customers, and develop customized products and services.” This builds up trust and collaboration among stakeholders, and establishes an efficient business climate in terms of electronic transactions. Yet, in practice, the digital transformation of Bulgarian SMEs is going through enormous hardships. These challenges come in the form of limited qualified personnel, budget restrictions, and disparity in digital infrastructure connectivity between rural and urban corers. A common challenge is that most SMEs neither have a structured digital strategy nor incorporate digital technologies into current business models. That these barriers are holding them back from fully reaping the benefits that digital solutions bring. To address these questions, this study conducted an empirical analysis comprised of expert interviews and a nationwide survey. Interviews with 12 digitalization experts supported essential success factors like management support, tools used and organizational and environmental elements. Through a stratified random sampling technique, 150 SME managers in diverse sectors were surveyed in a time period ranging from January 10 to February 10, 2025, resulting in 114 complete responses. The survey analyzed levels of digital adoption, whether any digital strategies existed, areas of digitalization and impacts on competitiveness. Quantitative data were analyzed through descriptive statistics, factor analysis, and correlations. The results of this study are a guide for SMEs who aim to adopt such digital technologies, policymakers who work for favourable mechanisms, and scholars who study digital transformation. The study, by both assessing the context as well as by assessing its inhibitors and facilitators of the digital transformation of SMEs, moreover serves as a key reference for both policy makers and business leaders, as the study offers clear recommendations to create a better environment for SMEs in BG to be more inclusive and better prepared for a better digital transformation
Novel variants of Hermite-Hadamard inequalities for (alpha,eta)-convex functions of 1st and 2nd kinds
No full textIn this article, we aim to present generalized results related to the well-known Hermite-Hadamard dual inequality for two distinct types of convex functions, employing various techniques such as Hölder's and Power mean inequalities. Consequently, both established and new results will be encompassed as special cases. Additionally, we intend to explore some relationships between our findings with well-known special means and trapezoidal formula
Problem Gambling Prevention for Children, Adolescents and Young Adults: a Narrative Literature Review
No full textAim: Numerous consequences of problem gambling (PG) affect individuals and families, so prevention of PG among the youngest is of high importance. This review points to the preventive interventions for children, adolescents and young adults based on multidimensional constructs to draw a comprehensive picture of this growing field. Materials and Methods: PubMed and Google Scholar were utilized to research literature and 17 studies met inclusion criteria. Results: Results show that PG prevention for adolescents and children are mostly school-based programs, which are primarily effective in improving the knowledge about gambling, correcting cognitive misconceptions, superstitious thinking and strengthening healthy attitudes. Programs that produce behavioural changes are those with an integrated prevention approach. Prevention among young adults is based on brief interventions providing feedback to those involved. Conclusion: The methodology in applied studies varies greatly, making it difficult to draw firm conclusions. Future studies on PG preventive interventions should follow consistent measurement of prevention outcomes, as exact behavior changes
Prof. dr. sc. Anita Pavković Banke i bankarstvo – trendovi i izazovi, Narodne novine, Zagreb, 2024., 348. stranica
No full textSerum lipoprotein(a) concentrations in presumably healthy Polish subjects in relation to age, sex, and cardiometabolic risk factors
No full textIntroduction: Lipoprotein(a) (Lp(a)) is an independent cardiovascular risk factor, primarily determined by genetic factors. This study assessed Lp(a) concentrations in presumably healthy subjects and evaluated its association with age, sex, and cardiometabolic risk factors.
Materials and methods: The study included presumably healthy 1046 adults and 276 children. Laboratory parameters: lipid profile, Lp(a), apolipoprotein B (apoB), glucose, HbA1c, C-reactive protein and creatinine were measured. Contributions of Lp(a)-apoB to apoB (%Lp(a)/apoB) and of Lp(a)-cholesterol to LDL-cholesterol (%Lp(a)-C/LDL-C) were calculated.
Results: Lipoprotein(a) concentrations were significantly higher in adults than in children (P = 0.014) and in women than in girls (P = 0.003), but showed no overall sex differences. In women, Lp(a) was higher after age 50, while in men a slight rise occurred after age 60. Lipid indices %Lp(a)/apoB and %Lp(a)-C/LDL-C declined in men until their 40s and was higher after 50 in both sexes. In a multivariable logistic regression model increased LDL-C concentration was a significant predictor of Lp(a) ≥ 0.30 g/L in women (odds ratio, OR = 1.77; P = 0.021) and children (OR = 2.83; P = 0.009). Boys had twofold higher probability of Lp(a) ≥ 0.30 g/L than girls (OR = 2.17; P = 0.024).
Conclusions: Lipoprotein(a) concentrations increase with age, especially after 50 in women and 60 in men, and are significantly associated with LDL-C. Rising %Lp(a)/apoB and %Lp(a)-C/LDL-C alongside falling apoB and LDL-C suggest greater atherogenicity in older individuals, particularly men. These findings support including Lp(a) in lipid profile for better cardiovascular risk assessment
Hydrodynamic interactions in midwater trawl nets: combined effects of flow velocity and door spreading through numerical and experimental approaches
Get PDFOwing to escalating fuel costs and dwindling fish stocks, optimising midwater trawl efficiency requires a thorough investigation of net design variables. To understand the morphological changes in a trawl net under different operating conditions, a numerical model of the trawl was established using the lumped-mass method. The effects of door spread and flow velocity on trawl morphology, drag force, and energy consumption coefficients were analysed. A generalised additive model was employed to predict the net configuration. In addition, the net mouth parameters of the trawl net were measured using scale model tests in a towing tank and full-scale sea trials to verify the reliability of the predicted results. This study provides guidelines for improving the geometric performance and catchability of midwater trawls
