Theoretical Background Research Articles

Are Your Laboratory Data Reproducible? The Critical Role of Imprecision from Replicate Measurements to Clinical Decision-making.

Measurement results of biological samples are not perfect and vary because of numerous factors related to the biological samples themselves and the measurement procedures used to analyze them. The imprecision in patients' laboratory data arising from the measurement procedure, known as analytical variation, depends on the conditions under which the data are collected. Additionally, the sample type and sampling time significantly affect patients' laboratory results, particularly in serial measurements using samples collected at different time points. For accurate interpretation of patients' laboratory data, imprecision-both its analytical and biological components-should be properly evaluated and incorporated into data management. With advancements in measurement technologies, analytical imprecision can be minimized to an insignificant level compared to biological imprecision, which is inherent to all biomolecules because of the dynamic nature of metabolism. This review addresses: (i) the theoretical background of variation, (ii) the statistical and metrological evaluation of measurement variation, (iii) the assessment of variation under different conditions in medical laboratories, (iv) the impact of measurement variation on clinical decisions, (v) the influence of biases on measurement variation, and (vi) the variability of analytes in human metabolism. Collectively, both analytical and biological imprecision are inseparable aspects of all measurements in biological samples, with biological imprecision serving as the foundation of personalized laboratory medicine.

Cognición social y política en la infancia y adolescencia

This text presents the theoretical discussion about how children and adolescents acquire social knowledge, and in particular, political knowledge. Within the framework of social cognition, the perspectives of the general domain and the specific domain are developed. The argument is made in favor of the latter position, as children and adolescents' knowledge of society—which is none other than the social environment in which they live—requires the construction and acquisition of specific concepts that are interrelated and form an entire domain-specific conceptual network. To better understand this discussion, the theoretical background, which invariably refers to the work of Jean Piaget, is first briefly presented. Finally, it is proposed that the concept of political cognition best explains the process of acquiring political notions during childhood and adolescence, and the psychosocial mechanisms that enable this are hypothesized.

Exploring the Gap between Theory, Practice, and Expectation in School Mentoring

Mentoring is a crucial aspect of teachers’ professional development, yet there is considerable debate among educators about its efficacy and some notable resistance against it. Thus, it is beneficial to examine teachers’ perceptions regarding mentoring in order to gain insight into potential discrepancies between mentoring theoretical background, practical experiences, and expectations. An originally made questionnaire was employed as the instrument for gathering data, thereby establishing a quantitative research design. The findings revealed that teachers hold disparate views on mentoring at three distinct levels: the theoretical level, the practice level and the expectation level. More specifically, the teachers’ perceptions assessed these three levels, with the practice level ranking the lowest, followed by the theoretical level, and the expectation level ranking the highest. These findings demonstrate that teachers generally agree and align with the theoretical aspirations of mentoring, yet they also indicate that this promise can fall short in practice. Furthermore, teachers propose an expectation-based approach to mentoring that could enhance both the theoretical and practical aspects.

On the Kalman Filter Parameter Estimation Methods for Blind Source Separation

Blind Source Separation (BSS) is a well-known problem in signal processing and still receives attention from the scientific community, given its applicability in different areas. This work presents a theoretical background overview of the Kalman Filter formulation and its applicability to the BSS problem as a parameter estimator in two different approaches: joint (JEKF) and dual parameter estimation (DEKF). These approaches are evaluated in different scenarios for first-order autoregressive source signals, with analysis of the initialization details, presenting simulation results and performance comparison with classic algorithms, SOBI and SONS, evaluated by SIR, MER and MSE. The results showed that both the JEKF and DEKF algorithms can perform separation in a two-source-two-mixture scenario. In general, over the scenarios studied, DEKF presented a better performance when compared to the JEKF on the evaluated metrics. However, neither algorithm correctly estimated the parameters for mixtures involving more than two sources, showing convergence issues and sensitivity to initialization for an increased number of sources.

Theoretical background of the game design element “chatbot” in serious games for medical education

BackgroundThe use of virtual patients enables learning medical history taking in a safe environment without endangering patients’ safety. The use of a chatbot embedded in serious games provides one way to interact with virtual patients. In this sense, the chatbot can be understood as a game design element, whose implementation should be theory driven and evidence based. Since not all game design elements are already connected to theories, this study aimed to evaluate whether the game design element chatbot addresses the need for autonomy rooted in the self-determination theory.MethodA cross-sectional study was conducted to compare two distinct chat systems integrated in serious games with one system being an open chatbot and the other system being a constrained chat system. Two randomized groups of medical students at a German medical school played one of two serious games each representing an emergency ward. The data collected included both objective data in terms of students’ question entries and subjective data on perceived autonomy.ResultsStudents using the open chatbot generally asked significantly more questions and diagnosed significantly more patient cases correctly compared to students using a constrained chat system. However, they also asked more questions not directly related to the specific patient case. Subjective autonomy did not significantly differ between both chat systems.ConclusionThe results suggest that an open chatbot encourages students’ free exploration. Increased exploration aligns with the need for autonomy, as students experience freedom of choice during the activity in terms of posing their own questions. Nevertheless, the students did not necessarily interpret the opportunity to explore freely as autonomy since their subjectively experienced autonomy did not differ between both systems.

Building a Comprehensive Model for Measuring and Analyzing Financial Literacy of Vietnamese Students: An Sem Approach

Objective: This study aims to build a comprehensive model to measure and synthesize Vietnamese students' Financial Literacy. Theoretical Framework: This paper adopted the OECD (2018) framework to measure financial literacy. The theory of planned behavior (Ajzen, 1991) provided a solid theoretical background for the study. We constructed the questionnaire based on the studies of Lusardi and Mitchell (2011) and Potrich et al. (2016). Method: We conducted a hybrid survey on a sample of 4,146 students in Vietnam and applied Structural Equation Modelling (SEM) to examine the interrelationships among three pillars of financial literacy. Results and Discussion: Financial Knowledge significantly impacts Financial Attitude and Behavior. Moreover, Basic Financial Knowledge is critical to Financial Attitude and Behavior. Students with higher basic knowledge scores tend to have good financial behavior practices. Young people are risk-averse and likely to control their spending and expenses tightly. Research Implications: This study is relevant to SDGs 4, 5, and 10. They help policymakers design and implement appropriate finance educational programs for Vietnamese youths to facilitate good practices in personal financial management and improve public awareness of its significance. The results provide a practical framework for related stakeholders to develop appropriate solutions for personal finance. Originality/Value: This study contributes to the literature by building a comprehensive model with an SEM approach to measure and examine the nature of Vietnamese students' financial literacy. Our study validates the theoretical framework for financial literacy in Vietnam with an inclusive sample. We adjusted the questionnaire to measure basic and advanced knowledge and clarified financial attitudes and behavior. Our study provides a basis for making a curriculum to educate students about financial management and behavior toward financial health and well-being, which contributes significantly to SDG4, 5, and 10.

Living Fossil: A Metaphor's Travels Across Popular Culture and the Foundations of Darwinian Evolution and Anthropology.

Throughout the Victorian era, the metaphor "living fossil" repeatedly crisscrossed social and scientific domains. The term existed in popular culture before and after Darwin's Origin. Most notably, it also operated as two distinct scientific concepts, one introduced by Darwin and another in cultural evolutionists' depiction of human living fossils. Serving in different ways, living fossils were typically aberrant, persistent and unchanging examples that contradicted an expectation of ongoing change and associated progress. We explore the development and relationships of living fossil applications, focusing principally on Darwin's concept. In Origin, Darwin deployed living fossils as exceptions that prove the rule of his principles of natural selection and divergence. He structured a case for the causal adequacy of these principles to explain living fossils' persistence, invariance, and taxonomic positions in gaps between other groups. As other natural historians began discussing living fossils and labeling new ones, Darwin's concept endured, but was subject to perceivable variation; associations with natural selection or divergence varied greatly and attributes of his living fossil examples were sometimes ignored. Cultural evolutionists adopted a view that human societies developed over time in a unilinear succession of stages. In this view primitive groups, their implements, languages, and cultures, stopped evolving at different points in the past and persisted unchanged into the present. While Darwin's concept and this anthropological concept were connected associatively to the evolution of languages and to themes of spatial isolation, prolonged stasis and disruption of expected progress, they inherited significantly different theoretical backgrounds and commitments.

On the application of Koutecky–Levich analysis to electrochemical processes involving metal complexes. 1. Theoretical background

The applicability of the Koutecky–Levich (KL) approach for the processes occurring in the systems of labile metal complexes is considered. According to the analysis of simulated RDE voltammograms, the use of classical KL relationships is possible if the predominant complexes are involved in the charge transfer process. In the opposite case, corrections to the initial voltametric data, taking into account the surface distribution of complexes and ligands, are required. The rationale and methodology for correction functions are presented. Inaccuracies in the estimation of kinetic and diffusion characteristics arising from ignoring the peculiarities of mass transfer of chemically interacting particles are analysed.

Possibilities for Further Development of the Airbags in the Case of Non-conventional Seating Positions

The first ideas and experiments aimed at protecting passengers from the vehicle’s internal components with airbags date back to the 1960s. Twenty years later, the airbag appeared in series production, in December 1980, the Mercedes-Benz S-Class (W126) was the first serial production car to be equipped with a driver airbag, and since its introduction, the use of airbag technology has been uninterrupted. Airbag systems are currently regarded as almost mandatory protection systems in a vehicle. The article generally presents the development of airbags used in cars, followed by the currently used airbag folding types. After that, the article presents the simulation of the airbag deployment, its types and theoretical background, as well as the most important stages of the deployment of the airbag. In the following, the article presents the results of the research so far in the case of frontal and side crashes. The next section of the article introduces the materials capable of absorbing energy, then details the simulation model built and the airbag concept created. The last part of the article contains an evaluation of the results and the summary. The modified seat examined in the earlier phase of the research and the airbag concept that is the subject of this research also fulfill the set goals, but the latter has a great advantage.

Individual Theodicies as Meaning-Making Models. Narrative Research Among Catholics and Lutherans

Abstract The paper presents the results of a study of individual theodicies among Polish Catholics and Lutherans, conducted with the use of both qualitative and simple quantitative methods. The theoretical background of the study involves combined perspectives of theoretical and empirical theology, sociology of religions, and narrative psychology. In-depth interviews conducted among religiously engaged individuals led to the distinguishing of 12 theodicy models used by Catholics and Lutherans as narrative frameworks helping to give meaning to difficult life situations. The list complements and enriches the previous lists drawn up by van der Ven (1993) or Hutsebaut (2003). The analysis compared each model according to the types of negative experience which could be placed within the respective frameworks of meaning, as well as for the emotional consequences the frameworks could evoke in the subjects.

Investments in human capital assets as a basis for sustainable socio-economic development

Aim. To conduct an in-depth study of the significance of investments in establishing human capital as key to socio-economic development, highlighting its role in ensuring the growth of labor productivity and quality of life.Objectives. The work analyzes the theoretical foundations of human capital and reveals its role in socio-economic development. It explores the concept of human capital assets, summarizing the main approaches to its study of scientists in Russia and in other countries. The article also considers the impact of human capital investments on the labor productivity growth rates in different sectors of the economy, including high-tech and traditional industries, taking into account the specifics of their functioning and the factors that determine the efficiency of human resources. It identifies patterns between the amount of investments in human resource development and their impact on production efficiency, as well as on the socio-economic development of the national economy.Methods. The study combines theoretical and empirical approaches. The theoretical background is based on the research works of classical and modern economists on human capital assets, their essence and significance. The empirical analysis is based on statistical data on labor productivity, the scope of investment in human capital assets and their socio-economic consequences. A comparative analysis of labor productivity in large enterprises is also used. Results. The importance of investment in human capital assets is presented as one of the most effective mechanisms for increasing labor productivity. The analysis demonstrated that organizations that invest systematically resources in improving the qualifications of personnel and implementing professional development programs achieve a significant increase in productivity and strengthen their competitiveness.Conclusions. Investments in human capital assets are a key factor in ensuring sustainable socio economic development. Their significance increases many times in the context of economic transformation, accelerated implementation of innovative technologies, and adaptation to new global and in-country challenges. For Russia, being under external economic sanctions and internal structural changes, priority development and support of human capital assets are becoming a fundamental condition for increasing labor productivity, achieving competitiveness, and ensuring a high quality of life for the population. An integrated and systemic approach is required, aimed at popularizing and increasing the effectiveness of investment in human capital assets. This approach will ensure the creation of a solid foundation for long-term social and economic progress, as well as strengthening the country’s competitive position on the world stage.

Thermal-Hydrodynamic Modeling Includes Fracture-Flow Analysis To Assess Well Flow

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper URTeC 4054832, “Horizontal Well-Flow-Profile Assessment: Advanced Thermal-Hydrodynamic Modeling With Fracture-Flow Analysis,” by Maxim Volkov, Yulia Fesina, SPE, and Natalya Kudryavaya, TGT Diagnostics, et al. The paper has not been peer reviewed. _ Production logging in horizontal wells plays a critical role in the strategic development of hydrocarbon fields. However, conventional diagnostic methods for reservoir evaluation often face challenges in interpreting well performance accurately because of complex flow patterns. The complete paper discusses the concept, applications, and continual evolution of a new 3D temperature and spectral acoustics modeling and logging approach. This methodology has undergone rigorous testing across diverse field trials, encompassing a variety of completion designs, logging conditions, and operational types, that have validated the effectiveness of the modeling approach and illuminated its potential. Theoretical Background and Modeling This section of the complete paper provides a comprehensive overview of a recently developed thermophysical model designed for the quantitative interpretation of temperature and pressure-logging data in horizontal wells. The model accurately details the dynamics of fluid flow and heat-transfer phenomena within a well with multiple fractures and drilled in an anisotropic reservoir. It describes complex interactions between the wellbore, surrounding geological structures, and fluid dynamics, thereby facilitating a deeper understanding of the reservoir’s behavior under various operational conditions. This advanced modeling approach enables more-precise predictions and improved decision-making in the management and exploitation of hydrocarbon resources. The complete paper details the theoretical foundations of the model, including equations related to the modeling of hydrodynamics and conjugate heat transfer. To enhance the understanding of downhole temperatures and reduce uncertainties in interpreting temperature anomalies, temperature logging typically is conducted alongside passive spectral acoustic tools. Measuring acoustic fields while flowing the well allows for the classification of the flow type at each measurement point within a 10- to 15-ft scanning radius. This approach helps identify turbulence (acoustic noise) from flow in the matrix, fractures, and their initiation points, and annular flow between the casing and liner and the sand interface, including cases of completion-integrity failure. Although modeling temperature is feasible without spectral acoustics, using hydrophones significantly aids in deciphering indicated temperature anomalies, detecting minor flow zones that may not produce temperature anomalies. Spectral acoustic data acquisition covers the same intervals as temperature logging but generally is performed during the upward pass at stations spaced proportionally to the number of tools used, with vertical resolution parameters set before the operation. Recent advancements have enabled a vertical resolution of 1 ft and the capability to assess the radial distance to the acoustic source. Temperature data are collected primarily during a continuous down pass at a speed of 15–20 ft/min. To calibrate the Cascade 3D model, it is advisable to use at least two different well operational regimes: shut-in and either flowing or injection. Two case studies are included in the complete paper to show the application of the described modeling in the horizontal producer and injectors, its ability to assess the temperature response in different well configurations such as openhole and smart completions, and its potential to identify and quantify the flow from the areas that are supposed to be isolated. Both surveys were conducted using coiled tubing methods under at least two logging regimes: shut in and flowing. The first case study is included in this synopsis.

ICT acceptance in social and healthcare context - A scoping review of theories and models.

Although Information and Communication Technology (ICT) acceptance processes have been studied widely in the social and healthcare context, the theoretical background of these studies is widely based on Technology Acceptance Models (TAM, TAM2, UTAUT) and their extensions. These theoretical models have been criticized for being overly simplistic and focusing narrowly on individual adopters' beliefs, perceptions, and usage intentions without considering multidimensional approaches to capture the complexity of certain phenomena. Thus, there is a need for identifying other approaches to study ICT acceptance in the complex and digitalizing social and health care context. The aim of this review is to identify and describe existing theories and models of ICT acceptance studies, other than TAM and UTAUT, in the social and health care context. In addition, the aim is to identify and classify the dimensions of ICT acceptance within these theories and models. JBI methodology for scoping reviews was used as guidance. A literature search was done on four electronic databases (PubMed, Scopus, Web of Science and CINAHL). The reporting was conducted by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for the scoping review (PRISMA-ScR). Further, descriptive statistics and inductive content analysis were used to analyse the theories, models and dimensions of ICT acceptance within them. 21 studies were included in this review. Results indicated that ICT acceptance in the social and healthcare context have been studied by using a variety of theories and models from different disciplines. Within these theories and models, organization, technology, human, sociocultural and environment were identified as the main dimensions of ICT acceptance in the social and healthcare context. This review provides an overview of the alternative theories and models of ICT acceptance and dimensions to be considered when assessing ICT acceptance in the social and healthcare context.

Bulk nonlinear metamaterials for generation of quantum light

Quantum states of light, such as fixed photon number (Fock) states, entangled states, and squeezed states, offer important advantages with respect to classical states of light, such as coherent states and thermal states, in different areas: they enable secure communication and distribution of encryption keys, enable realization of sensors with higher sensitivity and resolution, and are considered candidates for quantum computing and simulation applications. To accommodate these applications, suitable methods for generating the quantum states are needed. Today, the quantum states are often produced by a spontaneous nonlinear process in a standard nonlinear material, followed by a series of optical elements necessary for encoding the desired state on the generated photons. In this review, we consider an alternative approach of structuring the nonlinearity of the crystal so that the desired quantum state will be generated directly at the crystal, without the need for additional elements. Our main focus here is on bulk crystals having structured second-order nonlinearity. The rising interest in these nonlinear metamaterials is fueled by advancements in the ability to efficiently simulate and design spontaneous parametric downconversion (SPDC) processes, as well as by new capabilities of structuring the nonlinearity of ferroelectric crystals, either by electric field poling or by laser-induced writing. As a result, nonlinear metamaterials were recently used to directly shape the spatial and spectral correlations of quantum light that is generated in SPDC. The paper covers the theoretical background and the design and fabrication methods of bulk nonlinear metamaterials for generating quantum light, as well as a series of demonstrations of the use of metamaterials in quantum optical applications.

A Survey on Sensor-Based Techniques for Continuous Stress Monitoring in Knowledge Work Environments

Prolonged work stress has an extensive negative impact across modern society. Recently, it has become an increasing issue, specifically in cognitively demanding knowledge-intensive professions. To address the global necessity of timely detection and reduction of work stress, sensor-based automated methods for measuring stress are emerging. Physiological and behavioral sensor data enable the potential for continuous stress detection, but challenges still exist concerning the effort required from the user and the sufficiency of available information, especially for models that want to adapt to personal traits and stress perceptions. This survey paper focuses on sensor-based stress recognition enabling continuous unobtrusive stress monitoring in the knowledge work environment, with a user acceptance and load suitable for sustainable long-term adoption. We provide an overview of the theoretical background of work stress and review the recent developments of sensor-based stress assessment, emphasizing real-world studies using physiological, behavioral, and environmental data. In addition, we discuss the applicability and challenges of different monitoring methods, including user acceptance. The presented survey provides insights into automating the assessment of work stress and related factors to advance the development of personalized well-being solutions based on pervasive data.

Usage-Based Models Around and Inside BLC Theory: Commentary on Hulstijn (2024)

In his essay entitled “Predictions of Individual Differences in the Acquisition of Native and Non-Native Languages: An Update of BLC Theory”, Jan Hulstijn updates his theory of Basic Language Cognition (Hulstijn 2011, 2015). His central claim is that there is a fundamental difference between the Basic Language Cognition that is sufficient for dealing with oral language and the Extended Language Cognition required for handling reading and writing. In my invited commentary, I argue that used-based models of language provide a wider theoretical background that helps to ground Hulstijn’s theory. I illustrate what this means with reference to the Entrenchment-and-Conventionalization Model (Schmid 2020). Based on this model I discuss Hulstijn’s predictions regarding the extent of interindividual differences to be expected among L1-speakers and L-2 speakers.

A Systematic Review of Theoretical Foundations and Learning Effects in Gamified Flipped Classroom Research.

Gamified Flipped Classrooms (GFC) are increasingly implemented in teaching and have become a trending research subject. Gamification and Flipped Classroom (FC) literature expresses a clear need for a theoretical foundation that positively affects motivation, behavioral change, and learning. However, this requires an overview of the current theoretical foundations of GFC research. Therefore, this study conducted a systematic mixed studies review (SMSR) of the current theoretical foundations of GFC research and learning effects. Sixty-nine studies were identified after applying rigorously defined inclusion and exclusion criteria. The review revealed that a significant number of studies (25 of 69) lacked a theoretical foundation. In studies supported by theory, Self-Determination Theory (SDT) was most frequently employed. Moreover, only three studies used theories to design both gamification and FC components. While GFC research generally shows positive effects on learning, studies with a theoretical background reported a higher rate of positive GFC outcomes (56%), compared to only 29% for studies lacking a theoretical foundation. Future research should explore and attempt to link SDT and other theories to learning impacts.

Structural, electrical, and physical-mechanical properties of composites obtained based on filled polyolefins and thermoplastic elastomers.

The paper presents the results of a study of the influence of various mineral and metal fillers, as well as carbon black and graphite on the structural features and quality of composite and nanocomposite materials based on polyolefins and their modifications. High density polyethylene (HDPE), low density polyethylene (LDPE), various copolymers of ethylene with α-olefins, polypropylene (PP), polypropylene random copolymer, block copolymer of ethylene with propylene, etc. were used as polyolefins. The filler used was mainly carbon black (CB) and graphite, as well as various natural minerals. The objective of the review material under consideration was to demonstrate promising possibilities for obtaining electrically conductive composite and nanocomposite materials based on dielectric polymers, which are included in the polyolefins. The introduction section examines the state of the problem of development and research of electrically conductive nanocomposites, as well as the goals and objectives of the research. The theoretical aspects of obtaining and studying composite materials based on polyolefins are considered, where the main attention is paid to studying the influence of filler content on the structural features and properties of polymer composites. Particular attention is paid to the compatibility of the mixture components and the establishment of the relationship between the filler particles and the macrochains of the polymer matrix. The significant role of compatibilizers in improving the compatibility of mixture components is shown. The article presents scientific provisions and theoretical background that explain the mechanism of the compatibilization process and its influence on the pattern of changes in electrical conductivity, physical, mechanical, thermophysical and thermal deformation properties of nanocomposites. Much attention is paid to the development of thermoplastic elastomers, taking into account the specifics of the interaction of thermoplastic (polyolefin) macrochains with various synthetic elastomers based on natural, butadiene-nitrile, butadiene-styrene and ethylene-propylene-diene rubbers. The influence of the thermoplastic-elastomer ratio, carbon black and graphite, and their modifications on the structure and properties of nanocomposites based on thermoplastic elastomers is considered. Significant attention is paid to the study of electrical conductivity of nanocomposites based on thermoplastic elastomers. It has been established that the degree of crystallinity of polyolefins and thermoplastic elastomers has a significant effect on the formation of the interspherulitic amorphous region in filled composites, which, in turn, has a primary effect on the mechanism of formation of tunnel and electron conductivity.

Determinants of the operation of Polish spa enterprises during and after the COVID-19 pandemic in the opinion of managers

PurposePoland has a large number of spa enterprises providing spa tourism services, which is closely linked to the largely state-funded spa treatment. Both the period of the COVID-19 pandemic and the period of the following two years after the end of the pandemic involved many changes in the operation of these entities. The purpose of this study is to attempt to identify the determinants of the operation of spa enterprises during both periods, as perceived by managers.Design/methodology/approachData for the study were collected through individual in-depth interviews (IDI) conducted with managers of six Polish spa enterprises, diverse in many respects. This research was exploratory in nature, and inductive thematic analysis was used to analyze the collected data.FindingsThe results of the study indicate that during the pandemic, as a result of the influence of state institutions, macro-level determinants played the greatest role. In the post-Covid period, on the other hand, the surveyed managers paid special attention to personnel and legal conditions. Demand factors manifested by changes in the behavior of spa visitors as well as relations with the environment were also highlighted. The determinants pointed out by the managers were more often perceived as barriers to the operation of enterprises during the analyzed period. The research results show the multidimensional impact of the pandemic on spa enterprises and their subsequent adaptation to post-pandemic realities. The research provides a comprehensive understanding of the operational challenges and development opportunities of spa enterprises.Research limitations/implicationsThe adopted methodology is associated with certain limitations that open up new paths for further analysis and better understanding of the discussed topic. Undoubtedly, the limitation of this research was the small sample size, which resulted from the difficulty of reaching managers of spa enterprises or their unwillingness to participate in this type of research. Perhaps it would be necessary to establish broader cooperation with this environment, e.g. through active participation in conferences associating health resort companies, which would facilitate conducting research in the future. Another limitation was the lack of possibility to record interviews, resulting in the lack of transcription and limiting it only to the researcher’s own notes. This significantly narrowed the possibilities of data analysis. In future research, the theoretical background should be expanded to include literature describing the conditions for the functioning of spa enterprises during and after the COVID-19 pandemic in other countries with a spa operation model similar to Poland. Due to the fact that the research conducted for the purposes of this study was exploratory in nature, its results can be used as source material for further research, enabling a deepening of this topic. Thanks to them, it is possible to create measurement tools that allow the use of more structured qualitative methods (e.g. structured individual in-depth interviews or focused group interviews) or quantitative methods (surveys, questionnaire interviews).Practical implicationsThe results of this study give rise to certain practical implications. Spa enterprises must better prepare for future health crises through flexibility in work organization and sanitary protection. COVID-19 cases, which are still occurring, as well as other serious diseases, cause many negative health effects in patients, and their reduction may become an opportunity to diversify the scope of spa services toward rehabilitation but also prevention. This would allow for a fuller use of the potential of spas. However, in this case, the role of state institutions is also important, as they should include such services in the scope of spa treatment and the financing system. In the case of some spa enterprises, it is necessary to change the marketing strategy, aimed at better matching the offer to younger customers as well as developing promotional activities aimed at attracting new commercial patients. In crisis situations, problems with personnel were noticed, which should be prevented in the future through better management in this area, consisting, for example, of the implementation of motivational programs aimed at encouraging employees to return to work and improve their efficiency. It seems necessary to solve staff shortages, perhaps through education and cooperation with educational institutions as well as through the possibility of employing refugees.Originality/valueThe study fills a certain cognitive gap, as no previous research has been conducted among Polish spa enterprises covering the analyzed period. This research focuses on uncovering the challenges and opportunities for health resort businesses in crisis contexts.

The Importance of Universities in Training Engineers Committed to the Sustainable Cause

Objective: This paper aims to address the best practices related to the teaching, training, and education of engineering professionals whose projects should be guided by their environmental impact and their sustainable character. Theoretical Background: This section presents the main issues associated with the need for education and teaching on sustainability in universities, and in particular, in engineering courses. Method: This research was based on the collection and reading of academic articles collected from the ScienceDirect and Google Scholar databases. The keywords 'universities' and 'sustainability', with spellings in English, were associated. Results and Discussion: The results indicate an increase in academic publications on sustainability in higher education institutions, particularly since 2015. Although this increase is also observed in the engineering areas, the average is still lower than the total number of publications in other areas of knowledge, such as environmental sciences and energy. Research Implications: The presented study reinforces the urgency in adopting curricula in engineering courses in Brazil that are updated and related to environmental sustainability. Originality/Value: The period of climate change that the world is going through is undeniable. Changes in rainfall patterns, long periods of drought, desertification, and sandstorms are some of the most evident effects. All of them, in some way, are related to the linear mode of production and consumption, in which the disorderly and poorly planned extraction of existing natural resources is privileged. However, this current model is not capable of sustaining itself over time. Production alternatives must be researched and developed, allowing for the emergence of new production techniques and the improvement of existing ones, so that natural resources are conserved with less waste generation. Petrochemical, mineral extraction and refining, pulp and paper, and polymer processing units are examples of sectors that need to readjust to the concepts of sustainability and the sustainable development goals established by Agenda 2030. However, for the main points of change to be implemented, it is necessary to guarantee appropriate training for engineers. The precepts of environmental sustainability must be incorporated into their classical training, so that a new generation of professionals includes in their projects and research parameters aligned with the current and future demands of a planet that yearns for positive changes. In this sense, this article brings important reflections on this theme and the need to update engineering courses in Brazil..