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This paper presents the mathematical modeling of the oxygen transfer process using partial differential equations (PDEs). This process is crucial in various environmental and engineering applications, such as wastewater treatment, aeration systems, and natural water bodies, in order to maintain water quality. The authors solved the typical PDE for describing the change in oxygen concentration over time and present the developed model of the differential equation with the term “source”, indicating that the model could be used to optimize oxygen transfer in various environmental and engineering applications, contributing to improved water quality and system efficiency.

The transition towards a sustainable and renewable energy future is essential to mitigate climate change and reduce greenhouse gas emissions. Small–medium combined heat and power (CHP) systems are increasingly popular for distributed energy generation, as they offer improved energy efficiency and reduced emissions compared to traditional power generation systems. This article reviews recent research articles related to small–medium CHP systems, including their role in renewable energy systems, use of biofuels, steam injection, diagnostics, and carbon capture. Throughout the research, the high potential of coastal regions has been observed and studied as a solid base for the later development of CHP systems. Based on the reviewed literature, the highest potential solutions are proposed to be further investigated as an efficient, economical solution for generating electricity and heat for various small-scale applications.

Abstract Background The seeds of many plant species can be dispersed over long distances in animal fur (epizoochory). Quantifying epizoochory in the wild is, however, challenging, since it is difficult to measure the retention times of seeds in fur. These retention times depend on the acceleration that seeds experience and that can detach seeds from fur. Wildlife collars containing accelerometers may thus provide crucial information on epizoochorous seed dispersal. However, this is only the case if acceleration of the animal’s neck (where collars are attached) is informative of acceleration of the animal’s main body (where most seeds are transported). Methods We used accelerometers to simultaneously measure acceleration at the neck, breast and the upper hind leg of 40 individuals of eight mammal species spanning a large range of body masses (26–867 kg). We then quantified maximum acceleration as the 95%-quantile of the resultant acceleration (of all measured values in data intervals of 5 s). Results Maximum acceleration was comparable between the neck and breast but substantially higher at the hind leg. Maximum acceleration measured by neck collars and body mass jointly explained 81% of the variance in maximum acceleration of the breast and 62% of the variance in maximum acceleration of the leg. Conclusions Acceleration measured by neck collars is informative of the acceleration experienced by seeds attached to other body parts (breast and leg). When combined with animal movement data and lab measurements of how fur acceleration affects seed release and retention times, widely used collar accelerometers can thus be used to assess distances of epizoochorous seed dispersal.

The purpose of the study is to show that two simple models that take into account only the irreversibility due to temperature difference in the heat exchangers and imperfect regeneration are able to indicate refrigerating machine behavior. In the present paper, the finite physical dimensions thermodynamics (FPDT) method and 0-D modeling using the Schmidt model with imperfect regeneration were applied in the study of a β type Stirling refrigeration machine.The 0-D modeling is improved by including the irreversibility caused by imperfect regeneration and the finite temperature difference between the gas and the heat exchangers wall. A flowchart of the Stirling refrigerator exergy balance is presented to show the internal and external irreversibilities. It is found that the irreversibility at the regenerator level is more important than that at the heat exchangers level. The energies exchanged by the working gas are expressed according to the practical parameters, necessary for the engineer during the entire project. The results of the two thermodynamic models are presented in comparison with the experimental results, which leads to validation of the proposed FPDT model for the functional and constructive parameters of the studied refrigerating machine.

The paper presents experimental tests and theoretical studies of a Stirling engine cycle applied to a β-type machine. The finite physical dimension thermodynamics (FPDT) method and 0D modeling by the imperfectly regenerated Schmidt model are used to develop analytical models for the Stirling engine cycle. The purpose of this study is to show that two simple models that take into account only the irreversibility due to temperature difference in the heat exchangers and imperfect regeneration are able to indicate engine behavior. The share of energy loss for each is determined using these two models as well as the experimental results of a particular engine. The energies exchanged by the working gas are expressed according to the practical parameters, which are necessary for the engineer during the entire project, namely the maximum pressure, the maximum volume, the compression ratio, the temperature of the heat sources, etc. The numerical model allows for evaluation of the energy processes according to the angle of the crankshaft (kinematic–thermodynamic coupling). The theoretical results are compared with the experimental research. The effect of the engine rotation speed on the power and efficiency of the actual operating machine is highlighted. The two methods show a similar variation in performance, although heat loss due to imperfect regeneration is evaluated differently.

Keratoconus is a progressive corneal ectasia that may lead to severe visual impairment due to the irregular astigmatism caused by corneal thinning. In addition to its association with atopy, eye rubbing, or genetic component, late reports suggest the involvement of inflammation in the pathogenesis of the disease. Our aim was to determine the concentration of IL-4, IL-6, IL-10, RANTES, IFN gamma, and TNF alpha in the tear film of patients with keratoconus and their first degree family members. We analyzed forty-eight participants in an observational cross-sectional study. The diagnosis of keratoconus had to be confirmed in addition to a minimum of 47 D corneal refractive power by corneal topography readings provided by a Placido-based topography system and analysis of the pattern: irregular astigmatism with an asymmetric “bow-tie.” As for the other groups, the most important diagnosis criteria were a normal topographic pattern with a regular astigmatism. 17 keratoconus patients, 16 relatives, and 15 controls were recruited after clinical assessment as part of the research. The cytokine’s mean values were similar in the keratoconus group and the relatives’ samples but significantly higher compared to the controls. Important differences were found in IL-4 levels between keratoconus patients and relatives and between relatives and controls (mean difference of 302.42, p

Background. Hemiballismus is a rare hyperkinetic movement disorder characterized by irregular, poorly patterned, highamplitude involuntary movements of the limbs on one side of the body. While being usually a consequence of subthalamic nucleus lesions, hemiballismus is uncommonly associated with stroke in adults. Moreover, many debates remain regarding the physiopathology behind post-stroke hemiballismus and its optimal treatment. Case reports. In this context, the article aims to present two intriguing cases of hemiballismus arising from ischemic stroke, illustrating the intricate interplay between vascular pathology and movement disorders. Case 1 involves a 72-yearold female presenting with sudden onset left hemiballismus following incomplete right middle cerebral artery infarction, who received intravenous thrombolysis and had a good outcome. Case 2, an 80-year-old female presenting with abrupt onset right hemiballismus, with a suboptimal therapeutic response but self-remission after three months. Considering the inconclusive imaging results, this case highlights the diagnostic challenges and dilemmas encountered in the management of post-stroke hemiballismus. Conclusions. The authors propose a discussion by comparing the selected case reports with currently available data from the literature, focusing on the diagnosis and possible therapeutic strategies. These two cases underscore the importance of early recognition and tailored management of post-stroke hemiballismus, enriching the understanding of this movement disorder.

Online marketing covers a significant portion of what a brand's promotion strategy means today. Whether the focus is on the organic side of online marketing or the paid one, promotional efforts must be viewed with the same level of importance in building an effective campaign that generates controllable results. The choice of online promotion channels, where a company's potential customers spend their time, as well as the differentiation in types of content that can be uploaded play a significant role in determining consumers to actively engage with the respective brand. Authors from the specialized literature have conflicting opinions regarding the effectiveness of the various types of content uploaded by brands on their social media pages. Thus, there is the need of evaluating the effectiveness of the main existing content categories (informational, remunerative, entertainment and relational), as well as identifying that content that determines certain behaviors among online users, respectively changes in their level of interaction with a brand. To solve such a decision-making problem, we have conducted two direct researches. The first was a marketing experiment, on the Facebook and Instagram pages of a coffee shop, in order to determine the level of engagement users have based on the content type. We have made 12 social media posts, based on content type, length of the description text, the day of the week and the period of the day in which they were made public. The second research was a survey among the social media users following the coffee shop accounts, in order to evaluate the consumer’s opinion about the above-mentioned types of content. Comparing the results of the 2 researches, we have identified both correlations and certain existing contradictions between consumers’ actual behavior in the online environment and the preferences they state regarding the posts with which they are most likely to interact.

In the last years, as artificial intelligence (AI) is more and more widely accessible to everyone, a breakthrough for the course of business growth is also available. Having this in mind, the purpose of this study is to provide a comprehensive review of the impact of AI on the practice of marketing research. For this study a comprehensive literature review was included focusing on academic papers, research articles, industry reports, and relevant sources to gain insight into the application of AI in marketing research. The main findings of this research paper demonstrate how AI can revolutionize market research by improving data analysis, enabling personalization, enabling real-time insights, and addressing ethical concerns. Altogether, this study highlights the transformative impact of AI on market research, emphasizing its potential to improve data-driven decision-making, enable personalized marketing strategies, and address ethical concerns, thereby providing valuable insights for organizations seeking effective and integrative insights. AI provides practical recommendations and future research directions to help organizations realize the potential of AI and make informed decisions for successful integration implementations.

Over the years, along with the technological development and the migration of numerous activities from the offline to the online, we have come to live in a world where sedentarism prevails. In this context, now more than ever, sport has an essential role in the harmonious development of the young generations, as well as in maintaining the physical health of each individual. In Romania, since our first participation at the Olympic Games in 1900, sport has occupied a place of honor and athletes have been continuously supported to reach performance, while aiming to popularize and normalize an active lifestyle among the general population. However, coming out of the communist era (early 90’s) meant also the end of coherent strategies for sport and, thus, no more results in European and international competitions. When looking at a local level, this responsibility falls in the hands of local sports clubs so that every citizen can be given the opportunity to enjoy the benefits of doing sports, while sport passionate shall have, through appropriate coaching and guidance, the chance to reach performance. As such, this paper aims to emphasize the key role that marketing has in the sport industry and the importance of the promotional activities for the growth of local sports clubs. More specific, this paper comprises a description of the sports market, and at a local level, the situation of archery in Bacau city through an analysis of SAGA, the only archery club in town. The paper presents the results of a quantitative research aiming to uncover the attitudes, perceptions and behavior of Bacau citizens regarding sports in general, and in particular, archery. Based on these results, and on the current situation of SAGA sports club, in the last part of the paper we propose a promotional campaign for this club.

Young entrepreneurs need guidance because they come with a lot of energy and desire to do something, but if this energy is not properly directed and concentrated with the help of specialists, it will not materialize in anything constructive. This is where the role of the marketing consultant comes in, to help the entrepreneur understand what the clients' needs are, what the company can offer and how the two can be correlated so that in the end there is a mutually beneficial relationship. This paper presents the results of two researches, a qualitative one (using in-depth interview) among experienced entrepreneurs and a quantitative one (using survey) among young entrepreneurs at the beginning of the road. The aim of the qualitative research was to identify the marketing consulting services that entrepreneurs need in order to optimize the businesses they own and increase customer satisfaction. The objectives of this research include highlighting the importance of marketing for business growth, the perception of the need for marketing consulting and identifying the types of services needed in marketing consulting. The quantitative research aimed at identifying marketing consulting services for which entrepreneurs at the beginning of the road show interest, having as a basis for comparison the perception of entrepreneurs with more experience, so as to correlate them in order to obtain the optimal mix of services. Following the process of comparative analysis between the way experienced entrepreneurs see consulting and marketing services and the way entrepreneurs perceive them at the beginning of the road, we have built a proposition for implementing a service offer to help young entrepreneurs in terms of activity marketing.

Books have the power to transform people's lives. It is not an understatement to claim that the world we know today would not have developed as it has if books had not existed. Books have long been a staple of education and entertainment, and they remain an important tool for the investigation and dissemination of ideas. Over the years, the book industry has become larger and larger and, like many other industries undergoing transformation, new technologies are facilitating a shift in who determines the industry's value. The Internet paved the way for new technologies to emerge, allowing for changes in sales/distribution, publication, and where material might be accessed. With the rise in popularity of the e-book in the twenty-first century, for businesses and marketers, the process of understanding, analyzing and tracking consumer behavior is crucial for leading to a better understanding of the consumer and consequently, to a successful approach. Therefore, the study of consumer behavior represents the incipient stage of the journey to meeting consumer’s expectations and needs. This paper presents the results of a quantitative research with the main purpose of describing a clear perspective on book consumer behavior, what factors influence their book purchasing decisions, reading habits and preferences and some of the individuals’ favorite things about reading and books. One of the most conclusive questions for this research focused on the book format the participants use, obtaining a very big and unexpected proportion of respondents claiming that they still read printed book, which proves that books still hold their magic, despites different digital means of reading such as e-books.

Social robots are increasingly developed for the companionship of children. In this article we explore the moral implications of children-robot friendships using the Aristotelian framework of virtue ethics. We adopt a moderate position and argue that, although robots cannot be virtue friends, they can nonetheless enable children to exercise ethical and intellectual virtues. The Aristotelian requirements for true friendship apply only partly to children: unlike adults, children relate to friendship as an educational play of exploration, which is constitutive of the way they acquire and develop virtues. We highlight that there is a relevant difference between the way we evaluate adult-robot friendship compared to children-robot friendship, which is rooted in the difference in moral agency and moral responsibility that generate the asymmetries in the moral status ascribed to adults versus children. We look into the role played by imaginary companions (IC) and personified objects (PO) in children’s moral development and claim that robots, understood as Personified Robotic Objects (PROs), play a similar role with such fictional entities, enabling children to exercise affection, moral imagination and reasoning, thus contributing to their development as virtuous adults. Nonetheless, we argue that adequate use of robots for children’s moral development is conditioned by several requirements related to design, technology and moral responsibility.

In an era of massive expansion of digital communication, companies around the world and across industries face the challenge of engaging in fruitful and impactful online conversations with their customers. Within this context, a new need has emerged from companies eager to be present in online conversations that lack the inhouse willingness and power to dedicate resources to this around the clock activity. Such companies choose to establish partnerships with external digital marketing agency as a safer way to keep on reinventing themselves in the digital noise using the support of professionals in this area. This choice was the source of a new industry’s birth: the digital marketing professionals and their agencies, a constantly growing and rapidly expanding market. Since corporate clients have now multiple alternatives to choose from when selecting their digital marketing agency, a question has emerged as to what the expectations of corporate clients really are when referring to their relationship with their digital marketing agency. In order to discover the corporate clients’ perspective, a qualitative research was developed aimed at unraveling the depth of corporate clients’ expectations based on who they are and also on their previous experiences. Data was collected through in-depth interviews, a choice determined by the need of privacy when approaching sensitive topics like motifs, past experiences and future plans. The research results showed that among the most common expectations of corporate clients include attention to the clients’ specific needs, experienced staff of the digital marketing agency dedicated for their account, proactive approach and initiative of their digital team. In addition, when choosing their digital partners, corporate clients put great emphasis first on their fellow industry colleagues’ recommendations and second on the awards of their potential future partners. As a trend, corporate clients tend to have more than only one digital partner as a way to secure their partners’ eagerness to be competitive in the long run. Future research directions might approach the same subject from the other side, from the digital marketing agencies’ sides as means to compare and contrast perspectives and expand communication opportunities from both ways.

Knowledge has always been a never-ending growth space where the more we discover, the more there is to be discovered. Within this framework, research has played an enormous role as an organized and clearly determined space that generated fundamental change for everyone involved. The increasing number of discoveries has happened simultaneously with the increasing number of research areas that awake interest. But since the same research funds were insufficient in covering the new research topics, various funding alternatives have emerged in the recent years. And the biggest question that emerges relates to researchers’ familiarity with all the available opportunities in terms of research funding. In this context, the current research was developed, aiming to tackle with Romanian researchers’ awareness, interest and future plan when referring to winning a research grant. Major findings of the current research show that, despite extensive general research experience, Romanian researchers lack experience in applying for international grants and, to some extent, they even lack awareness about the available calls they could apply to. This finding opens the door for a shift in communication strategy about these grants, and also a new perspective in terms of institution’s research strategy.

Online migration characterizes both consumers and the business environment, which makes us see the integration of new technologies in this virtual environment as a natural development. User behavior requires additional efforts for technology adaptability, so integration does not seem to be forced, but the usefulness of such an immersion is felt by all companies, that want to have as much information about consumers as possible and monetize it in their strategy, by building up the most relevant products/services and communication campaigns. This is also the purpose of this article, which includes the results of a quantitative research among business representatives to assess their perception of the use of neuromarketing applications in online social networks. Although several apps were evaluated individually, the study indicates a high degree of utility for eye tracking and face coding, two methods through which companies can see the network users' direct and unaltered response to incoming messages.

Academic research and, more precisely, its funding have been a major concern for both institutions and policymakers. And one way to tackle with the shortage of funds compared to the huge diversity of research plans, various organisms have developed open competition grants like Horizon 2020 that have brought the support so needed for academic research. But the successfulness of such an initiative depends on academics and their willingness to apply and manage research projects funded from Horizon 2020 budget. Therefore, a direct research was conducted among the researchers from the Bucharest University of Economic Studies to determine their awareness about various funding options available for them, their experience when approaching a Horizon 2020 research grant and their future intentions in terms of research. The main finding of this research approach relates to Horizon 2020 grants low attractiveness among Romanian researchers determined by researchers’ lack of experience, self-confidence and institutional management support. This also shows that there is still room for improvement and growth in terms of knowledge, awareness and courage to obtain a Horizon 2020 grant that can be beneficial for researchers, universities, industries, countries and society as a whole.

This paper focuses on the multiple ways of building a brand in the current music industry, with a focus on Romania. The main idea of this paper is to determine the opinions of music consumers toward the brand of a musician, in general, and then to build different models and alternatives to the ones proposed so far, both while taking into account the elements and the characteristics proposed until now, as well as the answers given by the respondents. The research will focus on: the analysis of general attitudes and consumer behavior, with regard to music and the view of the consumers towards native Romanian singers and international ones. Moreover, the brand of a singer, from the perspective of associating the brand itself with the image created and with the primordial characteristics that must be respected by a singer, in order for them to be appreciated by the consumers, will also be discussed.

Since many of the factors influencing quality of life have both a transnational and a national dimension, in the last four years quality of life studies consider also the influence of the economic crisis on that phenomenon. Quality of life dimensions are analyzed from the perspective of economic indicators evolution during the crisis years, but also in terms of individual perception on quality of life in the present context of the market. This article highlights the changes in the quality of life studies due to the influence of the economic crisis. The analysis is made at the level of the research objectives, measurement indicators, methods of analysis and research methodology. The main consequence of the economic crisis for the quality of life studies refers to the fact that they are designed such that they respond better to the market new requirements for economic recovery, as well as to the individual needs of well-being.

Objects: To investigate the variability of the corneal hysteresis in primary open angle glaucoma(POAG) patients. Material and Methods: Out of 123 eyes, 99 carried out the inclusion criteria and were investigated further using Goldman Aplanotonometer to measure intraocular pressure(IOP), Ocular Response Analyzer(ORA) in order to determine corneal hysteresis (CH) and corneal resistance factor(CRF), ultrasonic pachimetry (Ocuscan) to measure central corneal thickness(CCT) and Humphrey visual field to determine mean deviation(MD), pattern standard deviation(PSD) and visual field index(VFI). The patients were divided into two groups: one group of diagnosed POAG patients and one control group of healthy individuals. Statistical analysis was performed using descriptive analyses and linear regression. Results: A considerable statistic correlation was found between CH and VFI both in the group of primary open angle glaucoma patients(r=0.52, P<0.0001), and the control group (r=0.22, p<0.04). Conclusions: The study shows a positive correlation, statistically significant, between corneal hysteresis and visual field index both in glaucoma patients and control subjects proving that a lower CH associates with a lower VFI. Ocular response analyzer can be considered a useful instrument in evaluation of primary open angle glaucoma patients.