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Scavenging for hydroxybenzoic acids in Cupriavidus necator: studying ligand sensitivity using a biosensor-based approach /
No full textThe increasing demand for rapid identification of bacteria capable of degrading environmentally relevant organic compounds highlights the need for scalable and selective analytical tools. Cupriavidus necator catabolizes several hydroxybenzoic acids, including 2-hydroxybenzoate (salicylate, 2-HBA), 4-hydroxybenzoate (4-HBA), and 3-hydroxybenzoate (3-HBA), funneling them into central aromatic catabolism via monooxygenation to 2,5-dihydroxybenzoate (gentisate, 2,5-dHBA) and 3,4-dihydroxybenzoate (protocatechuate, 3,4-dHBA) followed by the oxidative cleavage reaction, enabling complete conversion to tricarboxylic acid (TCA) cycle intermediates. To quantify how readily C. necator is able to activate catabolic genes in response to hydroxybenzoic acid, an extracellular ligand, we applied an approach centered on a transcription-factor (TF)-based biosensor that combines ligand-bound regulator activity with a fluorescent reporter. This approach allowed to evaluate the ligand sensitivity by determining gene activation threshold ACmin and halfmaximal effective concentration EC50. Amongst studied hydroxybenzoic acids, 2-HBA and 4-HBA sensors from C. necator showed very low thresholds 4.8 and 2.4 μM and EC50 values of 19.91 and 13.06 μM, indicating high sensitivity to these compounds and implicating a scavenging characteristic of associated catabolism. This study shows that the TF-basedbiosensor approach applied for mapping functional sensing ranges of hydroxybenzoates combined with the research and informatics of catabolism can advance our understanding of how gene expression regulation systems have evolved to respond differentially to the availability and concentration of carbon sources. Furthermore, it can inform metabolic engineering strategies in the prevention of premature pathway activation or in predicting competitive substrate hierarchies in complex mixed environments
Assessing the impact of opinion leaders on consumers of different generations.
No full textThe opinion leader marketing industry has been developing rapidly in recent years, with consumers paying more attention to information provided by opinion leaderss rather than direct advertising online. Therefore, opinion leaders have a strong influence on consumer behavior. In this regard, opinion leaders can be effectively used to promote various products and brands. However, research reveals that the impact of opinion leaders on consumers of different generations is uneven. Currently, there is not enough research that would reveal the aspects of the impact of opinion leaders on consumer behavior of different generations. The problem under study is defined by the problematic question: how is the impact of opinion formers assessed by consumers of different generations? The object of the study is the impact of opinion leaders on consumers of different generations. The aim of the study is to assess the impact of opinion leaders on consumers of different generations. Research objectives: to reveal the concept of opinion leaders and the dimensions of their impact on consumers of different generations; to present a classification of different generations and to analyze the characteristics of behavior; to form a theoretical model of the impact of opinion leaders on different generations of consumers; to assess the impact of opinion leaders on the behavior of consumers of different generations from the point of view of cosmetics consumers
The relationship between technological development and job satisfaction factors at UAB ORLEN Service Lietuva.
No full textTechnological development is rapidly transforming the working environment, nature of activities, and organizational structures in modern companies. Digitalization, automation, and the implementation of artificial intelligence increase work productivity and efficiency, while simultaneously introducing new challenges for employee well-being and job satisfaction. Job satisfaction is considered one of the key factors influencing employee motivation, work quality, and overall organizational performance. In light of this, the present master’s thesis examines the relationship between technological development and employee job satisfaction. The object of the research is the relationship between technological development and employee job satisfaction. The aim of the thesis is to determine the link between technological advancement and job satisfaction in the company UAB “ORLEN Service Lietuva.” To achieve this aim, the following objectives were set: 1) to reveal the concept of technological development and justify its importance to the organization; 2) to identify the factors influencing technological advancement in the manufacturing sector; 3) to present the concept of job satisfaction and its determining factors; and 4) to identify the relationship between technological development and job satisfaction in UAB “ORLEN Service Lietuva.” The research methods applied include scientific literature analysis and a quantitative empirical study (written survey). Job satisfaction was measured using P. E. Spector’s (1985) Job Satisfaction Survey (JSS), while the factors of technological development were assessed using a questionnaire designed by the thesis author. Data analysis was performed using SPSS 31.0 software; means, standard deviations, and frequencies were calculated, and correlation analysis was conducted. The empirical research conducted in UAB “ORLEN Service Lietuva” revealed a significant positive relationship between technological development and employee job satisfaction. The analysis showed that a more favorable employee attitude toward technological implementation is associated with higher levels of satisfaction across various aspects of work – from remuneration and career opportunities to interpersonal communication and work content. All five examined dimensions of technological development demonstrated statistically significant positive correlations with job satisfaction indicators (p < 0.001), with moderate to strong Spearman correlation coefficients (~0.62–0.74). Notably, even technostress correlated positively with job satisfaction in this study, suggesting that employees perceive technological change as an integral part of their work environment and do not associate related stress with general dissatisfaction at work. In conclusion, the research confirms that technological development in the analyzed company significantly contributes to higher employee job satisfaction. Therefore, strategic investments in new technologies and digitalization, when aligned with employee needs, may serve as a key factor in enhancing employee well-being
Impact of transmission constraints on critical grid elements and offshore wind power curtailment in Lithuanian power system /
No full textThe transition toward carbon neutrality is accelerating the deployment of renewable energy sources (RES), creating new challenges for power balance, stability, and renewable generation curtailment. In the Baltic States, this RES growth coincides with synchronization with the Central European Synchronous Area, which poses additional technical and operational challenges. This paper evaluates the integration of offshore wind farms (OWFs) into the Lithuanian power system for 2027 and 2035, focusing on their impact on system operation, transmission loading, power balance and power system strength. A methodology based on extrapolated historical hourly data is applied to assess Lithuanian power system security under large-scale RES penetration, identifying critical contingencies and lines most prone to overloading. Results indicate that in 2027, network overloads may occur under N–1 contingencies when OWF capacity reaches 1400 MW; higher capacities require curtailment to maintain the generation–load balance. In 2035, planned grid reinforcements eliminate N–1 overloads. However, in both years, system strength remains the limiting factor. With an admissible short-circuit ratio (SCR) of 3, the maximum allowable OWF capacity is 1141 MW in 2027 and 1582 MW in 2035 under N–1, and 562 MW and 1039 MW under N–2 conditions
Vibrational transport of granular materials achieved by dynamic dry friction manipulations /
No full textThe use of vibrational transport for granular materials has significantly increased in the technological industry due to its reliability, operational efficiency, cost-effectiveness, and relatively uncomplicated technological setup. These transportation methods typically utilize various forms of asymmetry, such as kinematic, temporal (time), wave, and power asymmetry, to induce controlled motion on oscillating surfaces. This study analyses the motion of the granular materials on an inclined plane, where the central innovation lies in the creation of an additional system asymmetry of frictional conditions that enables the granular materials to move upward. This asymmetry is created by introducing dry friction dynamic manipulations. A mathematical model has been developed to describe the motion of particles under these conditions. The modelling results proved that in an inclined transportation system, the asymmetry of frictional conditions during the oscillation cycle—created through dynamic dry friction manipulations—generates a net frictional force exceeding the gravitational force, thereby enabling the upward movement of granular particles. Additionally, the findings highlighted the key control parameters governing the motion of granular particles. λ, which represents the segment of the sinusoidal period over which the friction is dynamically louvered, serves as a parameter that controls the velocity of a moving particle on an inclined surface. The phase shift ϕ serves as a parameter that controls the direction of the particle’s motion at various inclination angles. Experimental investigations were conducted to assess the practicality of this method. The experimental results confirmed that the granular particles can be transported upward along the inclined surface with an inclination angle of up to 6 degrees, as well as provided both qualitative and quantitative validation of the model by illustrating that motion parameters exhibit comparable responses to the control parameters, and strongly agree with the theoretical findings. The primary advantage of the proposed vibrational transport method is the capacity for precise control of both the direction and velocity of granular particle transport using relatively simple mechanical setups. This method offers mechanical simplicity, low cost, and high reliability. It is well-suited to assembly line and manufacturing environments, as well as to industries involved in the processing and handling of granular materials, where controlled transport, repositioning, or recirculation of granular materials or small discrete components is required
The impact of macroeconomic and environmental factors on the automotive market in Lithuania.
No full textThe automotive market is a very important area in both economic and ecological terms, strongly related to the salary, the economic condition of the country and it’s applied policies. The constantly expanding and updating of the European Union's "green deal" regulations, aiming at decarbonization and the lowest possible emissions, affect car fleets and their trends, especially when the markets are small, such as in Lithuania. It is also necessary to clarify the vulnerability of these specific car segments to macroeconomic indicators, in order to find out how economic cycles affect them. To find the connections and offer reasonable recommendations, it is necessary to conduct an empirical study, assessing how and to what extent these indicators affect sales. The Lithuanian context is examined due to limited number of similar studies in the country and also acknowledging the fact that considerable number of them have been conducted in other countries
Factors determining the company’s export strategic decisions.
No full textIn today’s global economy, companies’ exports are an integral part of business. Both exporting and non-exporting companies experience the consequences of international export activity: imports of goods or services increase competition in the domestic market and reduce the intensity of profitability growth. The interpretation of factors and logically grounded strategic export decisions enable companies to maintain a competitive advantage, increase production volumes, expand the scale of operations, increase profit, and become international
Trends in improving internal control in the construction services sector.
No full textThis master’s thesis examines the role of internal control systems and their improvement directions in construction service companies. In today’s dynamic and high-risk business environment, particularly in the project-based construction sector, internal control functions not only as a formal compliance mechanism but also as a strategic tool for risk management, ensuring project quality, deadlines, and financial discipline. The theoretical part analyses scientific literature and key models (COSO, LEAN, AI-based solutions), defines the concept and principles of internal control, identifies typical risks and control weaknesses, and highlights the importance of integrating internal control into organisational culture and everyday processes. The object of the research is the internal process control system in construction service companies. The aim of the thesis is to evaluate the internal process control system in this sector and, based on empirical research, to justify its improvement directions. The research problem is formulated as follows: how to ensure effective internal control in the construction sector in order to minimise risks, improve project management efficiency, and ensure compliance with legal requirements? The research employs scientific literature analysis, semi-structured interviews and a questionnaire survey in medium and large Lithuanian construction service companies. The collected data were analysed using qualitative content analysis and mathematical–statistical methods. Empirical results show that internal control systems in the surveyed companies are functioning but remain fragmented. Four main groups of weaknesses were identified: structural and organisational, process-related and risk management, technological, and cultural, motivational and competence-related. Control measures are applied unevenly across project phases and organisational units; risks are often identified only after deviations occur; digital systems are poorly integrated; employees’ attitudes towards control and their involvement in control processes are inconsistent. Based on these findings, improvement directions were formulated, focusing on setting a minimum control standard for all project phases, clarifying responsibilities, shifting risk management from reactive to preventive, implementing “single source of truth” and digital integration principles, and strengthening control culture and employee competences. The results of the thesis have practical relevance for medium and large construction service companies seeking to systematically impro
Application of apple by-products and xanthan gum in the development of fiber-enriched gluten-free muffins /
No full textThe growing demand for gluten-free bakery products requires the development of formulations that overcome their typical technological and nutritional limitations. Using fruit by-products as natural fiber sources, in combination with xanthan gum (XG), supports a sustainable ingredient strategy that improves gluten-free product quality. This study investigated the effect of apple pomace (AP) (5% and 10%) and XG (1%) on the technological properties, texture profile, nutritional composition, and sensory acceptance of gluten-free muffins. Six formulations were prepared by partially replacing maize flour with AP and/or adding XG. AP (5–10%) reduced muffin height and volume compared with the control, whereas 1% XG increased muffin height by 11.16% and raised volume and specific volume by 38.46% and 36.11%, respectively. XG significantly decreased hardness compared with the control, while the effect of AP on texture was concentration-dependent: 5% AP reduced hardness, whereas 10% AP did not further improve softness. Combined use of AP and XG resulted in complementary effects, improving structural properties while increasing dietary fiber content. The muffins supplemented with AP were acceptable, and their overall acceptability did not differ significantly among the tested formulations. Overall, the results demonstrate that incorporating AP together with XG enhances both the technological and nutritional quality of gluten-free muffins, supporting the valorization of fruit-processing by-products in functional bakery applications
Factors of high-tech industry export growth in European Union.
No full textThe high-technology industry is one of the most important drivers of economic growth and competitiveness in the European Union. Continuous technological development creates favourable conditions for innovation, expansion of production, and export growth. Increasing global demand for advanced technologies encourages European Union firms to strengthen their positions in international markets, while various factors significantly influence the dynamics of these processes. Exports represent one of the key components of high-technology sector development, enabling countries to diversify their economies, reduce dependence on domestic demand, and strengthen international economic ties. Despite the importance of the high-technology industry, the European Union faces strong competition from the United States and Asian countries, raising the question of which factors actually determine the growth of high-technology exports in the European Union