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The model of a photoacoustic gas-microphone signal in the time domain recorded in a transmission configuration using a minimum volume cell is derived. This model takes into account the inertial thermal relaxations of both the sample and the gas filling the cell by means of the generalized hyperbolic theory of heat conduction. With the introduction of electro-thermal analogy for the thin sample and short microphone length cavity, characteristic quantities are defined, which can be used in solving the inverse problem in time-domain photoacoustic in both cases, when thermal relaxations are neglected as well as when they are considered. The derived model that includes thermal relaxation explains the experimentally observed occurrence of overshoots and undershoots as well as an oscillatory approach to the steady values of the recorded signal in high-resolution time-domain photoacoustic measurements of thin semiconductor membranes, which will be presented in detail in Paper II of the paper. [ABSTRACT FROM AUTHOR]

In order to make the photothermal effect detectable from a sample with low optical absorption, an optically opaque layer must be applied on its surface. A model of optically induced temperature variations for such a structure is derived, with a very thin coating applied on the non-illuminated (back) side of the sample and neglecting heat flux dissipation in the coating. Validation of the model is performed by comparing the obtained results with the results for the corresponding two-layer structure model. The influence of optical absorption on surface temperature variations of both optically transparent and semi-transparent film, whether the film is a good or poor thermal conductor, is analyzed. It is shown that the effects of optical absorption in the coated structure can be observed through variations in the measured temperature, despite the low absorbance of the sample. [ABSTRACT FROM AUTHOR]

In this paper, a self-consistent inverse procedure is developed for the estimation of linear thermal expansion coefficient and thermal diffusivity of solids from transmission photoacoustic measurement. This procedure consists of two single-parameter fitting processes applied alternately: phase data are fitted by shifting thermal diffusion coefficient, while amplitude data are fitted by shifting thermal expansion coefficient. Each fitting process uses the resulting parameter of the other, previously finished one, thus converging to the best solution-pair achievable. In numerical experiments, the convergence proves to be very fast. The achieved parameter estimation error is as low as 1%, and it can be lowered further more by increasing the fitting resolution in parameter space. The application of the procedure on experimentally obtained aluminum photoacoustic response (measurements) on three thickness levels returns the estimates of its thermal diffusion and thermal expansion coefficients within expected literature boundaries. [ABSTRACT FROM AUTHOR]

In this paper, a theoretical model of temperature variations is derived for a two-layer optically absorbing structure, including thermal memory effects. It is considered that the two-layer structure is surrounded by gas and illuminated on the front side by a harmonically modulated laser beam. This model is based on the hyperbolic theory of heat conduction and Beer–Lambert's law of absorption neglecting multiple optical reflections in each layer. The derived model represents the generalization of the current models in two aspects. First, the influence of thermal memory properties of both layers is accounted for, and second, both layers are regarded as volume absorbers of the incident light. Based on the derived model, the expressions for surface temperature variations are given and discussed for the special type of two-layer structures, irradiated on the coated side, which is a prominent configuration in photoacoustic and photothermal experiments. It is shown that there exists a frequency range in which the influence of the thermal properties of the coating cannot be neglected, especially at the high-frequency range in which thermal memory of coating becomes significant. It is an important result in terms of understanding experimentally measured photothermal and photoacoustic response and, consequently, accurate characterizations of various high optically reflected and/or optically transparent samples by using these experimental techniques. [ABSTRACT FROM AUTHOR]

In this study, an NMR spectral analysis of the mixture of diastereomeric acetals, synthesized from 2,3-dihydrofurane and a racemic mixture of citronellol, was performed. 1H-NMR full spin analysis was achieved by manually adjusting δH and J values (previously calculated using the Spartan software) to fit the experimentally available values, followed by further optimization using MestreNova software. The simulated 1H- and 13C-NMR spectra of individual diastereomers, as well as their superimposed and summed spectra, were compared with the obtained experimental spectra. Spin simulation of proton signals was particularly useful for the assignment of the diastereotopic protons of tetrahydrofuranyl moiety and diastereomer discrimination. The NMR spectral data of individual diastereomers – chemical shifts, coupling constants, HMBC and NOESY interactions were systematized in appropriate tables and schemes. To the best of our knowledge, this is for the first time that the complete assignment of tetrahydrofuranyl moiety was performed, and the data obtained herein may be of great importance for the utilization of this protecting group in the future.

Court expert plays important role in the road traffic accident expertise. The question is how to select an appropriate court expert and what guarantees the quality of expertise. A road traffic accident expertise requires expert competencies and a comprehensive court expert register. The analysis of expert competencies in the road traffic area is performed by surveying the available data from the registers of Serbia, Montenegro, Bosnia and Herzegovina, and North Macedonia (non-EU states) and Croatia and Slovenia (the EU states). A comparative review of legal solutions in the observed states was done in order to consider the legal bases for expertise. Proposal for improvement is made. The capacity indicators of states for performing expertise were defined and an analysis was carried out showing the highest load was on the Slovenian experts (1 day per expertise), while in Bosnia and Herzegovina-District of Brčko the indicator amounted to 34 days per expertise.

Urban forests represent networks, that is systems, that include forests, groups of trees, and individual trees in urban and peri-urban areas. They are one of the primary types of green infrastructure in cities, enhancing living conditions for residents and providing a wide range of ecosystem services. This paper analyzes the urban forest of Košutnjak, whose area extends into the urban core of Belgrade. The needs of its users have been analyzed, as well as the current management practices, all with the aim of formulating proposals for measures to achieve a resilient ecosystem and establish sustainable management of this protected area. Additionally, the goal of the conducted research is to raise awareness among residents about the benefits provided by this urban forest, as well as its cultural and historical significance, which gives this area national importance.

Ian McEwan, an influential and provocative British novelist and short-story writer, has addressed a variety of issues, distinguishing himself as a socially and politically engaged author. This paper explores contemporary liberalism as depicted in two of McEwan's novels, Black Dogs and Saturday, both charged with moral complexity. The analysis is approached from the perspective of value pluralism, which recognises the plurality of morally correct yet incompatible and incommensu-rable principles or values. These values may conflict with each other, but since all are correct, the conflicts remain unresolved. It is the author's belief that the novels highlight value pluralism through characters who, while navigating a pluralist environment, disclose the challenges and limitations of liberal democracies. The theoretical context this paper relies on is based on ideas of Isaiah Berlin and his notion of value pluralism.

A growing body of evidence suggests that invasive plants can affect the stability of the ecosystem’s key species and influence flows and transformations of matter and energy in ecosystems. Since Symphyotrichum lanceolatum complex is one of the highly invasive plants in Serbia and many European countries, this study set out to determine floristic richness, struc­ture, and differentiations among the wet sites near linear corridors and to investigate the significance and representation of S. lanceolatum in degraded wet habitats. Accordingly, floristic diversity and the presence of other invasive plants were investigated in 22 wetland habitats. Overall, a total number of 179 plant taxa was found. Results showed four coenological groups. According to the invasive species coverage index (D%), S.lanceolatum dominated in all stands. Overall, based on the results, this study strengthens the idea that wet habitats belong to the group of habitats that are most susceptible to plant invasion.

It is known that green roofs mitigate the negative effects of climate change and environmental changes in cities. The paper presents research related to the determination of the methodology for the selection of autochthonous plant species of the flora of Serbia that would find application in the design of green roofs. The area of city of Belgrade was considered a pilot area. In order to achieve the set goal, the basic climate characteristics of the Belgrade area were considered, as well as the ecological and morphological characteristics of the plants, using the appropriate methodology. Based on the set criteria, a list of autochthonous plants of the flora of Serbia that could be used for the design of green roofs was proposed. When choosing plant material, care was taken to select different groups of plants: annual, biennial, and perennial plants, grasses, and succulents, considering that each of these groups of plants contributes in different ways to the stability and decorativeness of the green roofs.

Modern, systemic understanding of resilience as the ability of the individual, but also the community and other systems to select and provide the resources needed for positive functioning despite risk exposure, has opened space for designing programs that will provide the same resources. A review of the literature shows that experts and scientists have successfully directed the results of practice, which refer to the positive systems functioning despite the presence of risk, to create recommendations for designing programs that will help individuals, communities and other systems to build resilience. Such programs are of particular importance for victim empowerment. This paper aims to explain the basic assumptions of the effectiveness of programs aimed at building system resilience, which relate to the elements of assessment, design principles and key characteristics of resilience-building programs.

In the era of digitalization, boosted by Covid-19 pandemic, there is a constant need to measure the success of digital education, compare and reappraise its positive and negative outcomes, which are mainly dependent on the technical conditions available, as well as on the extent to which the previous knowledge of teachers has been adapted to practical and technical challenges. The aim of this paper is to present an analysis of the advantages and disadvantages of digitized education as perceived by students in a qualitative survey, conducted in 2021/22. The starting point were two hypotheses related to positive aspects and two hypotheses related to negative aspects of online learning. An in-depth interview was conducted among 20 high school and 20 university students. By analyzing the results obtained, and juxtaposing them with the data taken from a quantitative survey administered prior to the qualitative one, in 2020/21, it is possible to compare the changes that took place and gain a better insight into the entire process, which has undergone certain improvements, but which also leaves room for further enhancement, particularly in terms of students' and teachers' motivation to actively engage and interact. This would help students overcome their distrust of online education.

The right hemisphere has traditionally been considered as dominant in odor and emotion perception, whereas little is known about odor influence on emotion recognition. This study aimed to examine a possible difference in the recognition of basic emotions presented to the left or the right visual field following short-term left or right nostril treatment with an unpleasant odor. A total of 60 right-handed female participants completed an emotion recognition task in conditions of the right and left nostril treatment with an unpleasant odor (isovaleric acid). Results showed the right hemisphere advantage in speed, but not in the accuracy of basic emotion recognition after the right nostril treatment with an unpleasant odor, while the left nostril treatment had no effect. The right hemisphere and valence-specific hypotheses in emotion recognition were not confirmed, whereas the model of the right hemisphere dominance in odor perception was confirmed. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 179002]

The concept of university sports in Serbia is still dominantly based on occasional sports manifestations (competitions) for students. Mostly in the shape of single ad-hoc tournaments in different areas of sport or as competitions of student athletes within the University sports association. The current position of a majority of student population in terms of university sports in Serbia can be characterized as passive (spectators), while direct participants, who are recruited from the field of active competitive sports, have this only as an “additional” obligation within the sport they already practice in “their” sport clubs. Therefore, students’ perception of the role of sports/physical activity at university represents a very important determinant for creating adequate (new) program contents, concepts and for the implementation of physical education in higher education institutions in Serbia. The goal of this research, which is realised as an empirical non-experimental study, is to identify the attitude and opinion of students about the role of sport and organized physical exercising at university. The sample involved 227 students at the University of Novi Sad and Educons University from Sremska Kamenica. Survey was used as the basic research technique, and the instrument was constructed as a questionnaire whose basic semantic structure was based on similar instruments used in a few earlier studies. The results showed that the currently trend indicates a drop in regular practice of sport after enrolment in faculty, but youth positively perceive the role of sports at higher education institutions, clearly recognizing its importance in social interaction. Therefore, pedagogical implications of this research can certainly dominantly relate to management structures of higher education institutions in shape of a clear message about the necessity to introduce more intense education of all education stakeholders about the values and importance of physical activity (physical exercising) of youth. In that context, they also encourage changes in overall education policy in Serbia.

Previous studies have demonstrated a strong association of criminal behavior of juvenile delinquents with delinquents’ personality traits and family interactions. However, little is known about the extent to which family interactions and personality traits are associated with criminal recidivism. The present study aimed to examine these relationships, using the Velikih pet plus dva (Big Five Plus Two) – short version (assessing Neuroticism, Extraversion, Openness to experience, Conscientiousness, Aggressiveness, Positive Valence, Negative Valence), The Quality of Family Interaction Scale (Satisfaction with family, Mother and Father Acceptance/Rejection), and official data from criminal records. The study included 61 institutionalized delinquents and 64 non-delinquents, 15 to 18 years of age. Neuroticism, Openness to experience, Conscientiousness, Negative valence, acceptance by father and rejection by mother are statistically significant predictors of criminal recidivism in juvenile delinquents. Delinquents showed higher Neuroticism, lower Conscientiousness and acceptance by mother compared to non-delinquents. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 179002]

As a kind of hallmark of social progress, youth entrepreneurship is represented as a field of study at all levels of formal education in the EU countries. While this trend is insufficiently present in Serbia, it is of great importance to identify the factors that influence the attitudes of high school students and university students in the choice of future profession. Although young people, generally, have positive perceptions on entrepreneurship, a small number of them start their own businesses. As the greatest obstacle in the realization of entrepreneurial ideas, they recognize the unfavourable social environment, i.e. above all, the financial requirements in the initial stages of doing business, high tax levies, legislation, as well as the lack of institutional support. Research results presented in this paper indicate the possible reasons for such respondents' attitudes, as well as the fact that young people have most trust in their families and friends, and least trust in state institutions and banks.

The purpose of the study is to defining and assessment of the impact of the determinants affecting the development of entrepreneurship in Vojvodina's sustainable tourism. The empirical part of the study was conducted using the Survey method. The basic research instrument was a questionnaire. Its construct was based on the factor models of entrepreneurship, amended and adapted with item entries which can be deemed correspondent with particularities of the tourism environment of the AP of Vojvodina. The results indicate that the factors of Education and Partnership are the determinants with the strongest influence on the development of entrepreneurship in Vojvodina's sustainable tourism. Factors such as education and partnership are rated with the highest impact. Partnership, education, and cooperation between all interested stakeholders are a prerequisite for sustainable tourism in Vojvodina.

Causes of organizational changes in sports are dominantly conditioned by changes in environment – external and internal. Because of that, the main goal of changes in sport karate needs to lie in reshaping sports (karate) organisation in a way which would also allow for achieving “internal and external harmony”, i.e. improvement of overall organisational performance (regardless of whether that organization is club or association) which will have appropriate capacity to efficiently and effectively adapt to changes in the environment. One of the changes which can be considered “radical” in the context of sport Karate is decision of the International Olympic Committee that karate, as defined by the organizational concept of WKF, be included in the programme of Olympic Games in Tokyo 2020. This is an important factor which directs changes in the system of our sport Karate (in Serbia and Vojvodina). Because of that, karate in Vojvodina faces a usual managerial dilemma related to the period and manner of introduction of changes, i.e. answer to the question – how to start? Every organization or individual, in accordance with environment and context of change inclusion, reacts in different ways. Every authenticity of change is conditioned by “throughput” of a greater number of internal and external elements of a karate organisation. Because of that, essential assumption for a correct answer to the question asked lies in quality and responsible mutual cooperation of people in organisations. This cooperation is also based on testing of different ideas, communication in the function of constructive debate about problems, creation of authentic (personal) models of changes and adoption of appropriate strategies. One of the first steps in strategic directing of changes in karate is, surely, a studious and detailed analysis of the sport karate environment. This paper, essentially, presents a shorter theoretical analysis and an explication of basic factors which have defined the development of karate in Vojvodina, as an assumption (a hypothetical frame) for more complex future analyses of sport karate environment, necessary for the preparation and creation of strategic documents for development of karate as an Olympic sport.

Parental discipline is defined as parental educational method of learning acceptable and modifying unacceptable child behavior. Punishment, as a part of corrective discipline, is focused on inappropriate behavior with an intention to correct it. Basic characteristics of punishment, such as intention and unpleasantness, drew attention of scientists and experts and led to a discussion regarding their justification and effectiveness. The aim of the paper is to present the basic characteristics and types of punishment, effects and factors of its successful use, and current efforts of experts who are trying to shift parents' actions from punishment to positive discipline, which means encouraging and stimulating desirable behavior and developing self-discipline.

In this work it has been shown that both the laser desorption/ionization mass spectrometry (LDI MS) and the matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) are the simple and quick methods for determination of relative natural isotopic distribution of lead. The analysis of metal salts with these approaches does not require any time-consuming preparation of samples: a single run can take only a minute, and numerous information can be obtained. Results obtained in this work show that chosen matrix has no negative effect on quantitative determination of lead isotopes and support once more the applicability of MALDI TOF MS for lead isotope distribution determination in the sample, and accuracy of data obtained. Additionally, the generation of PbnOn and PbnOn-1 (n: 2 - 6) clusters have been successfully achieved in the positive mode, using the both LDI and MALDI methods. All stoichiometries were confirmed using isotopic pattern modelling. [Projekat Ministarstva nauke Republike Srbije, br. 0172011]