Search

This paper explains automatic differentiation, discussing two primary modes - forward and backward - and their respective implementation methods. In the context of issues encountered in machine learning and deep learning, the forward mode is deemed more suitable as it efficiently differentiates functions with numerous inputs compared to outputs. Given Python's pivotal role in the ML landscape, the paper elaborates on two widely used deep learning libraries-PyTorch and TensorFlow. While both these libraries support automatic differentiation, they adopt distinct approaches, each carrying its unique strengths and weaknesses.

The goal of this paper is to provide a comprehensive overview of application of multi-criteria decision making (MCDM) methods in papers from the field of ecotourism and sustainable tourism. A search has been done of the relevant terms in titles, abstracts and keywords found in papers from 26 prominent journals from the field of tourism belonging in Web of Science (WoS) Clarivate Analytics. It has been established which MCDM methods were used and who are the most common authors of such papers. A keyword frequency analysis was also performed. It is established there are 39 papers in the field of ecotourism and sustainable tourism where MCDM methods were applied whereby all were published after the year 2000, as well as that their number is constantly increasing.

With the view to creating a favourable business environment and legal security in the market of the Republic of Serbia, a single and centralized register of business entities has been created, in which data on measures of temporary restriction are recorded. These measures are based on acts of courts, the central bank, the Tax Administration and other competent authorities. The research was conducted on a sample of 1,595 observation units (measures imposed on active business entities) found in the database of active measures of temporary restrictions and published on the website of the Business Registers Agency. The research spanned over almost five years (from 2017 until the first half of 2021). The results of the research show that a total of 1,422 measures of temporary restrictions were imposed by various decision-makers. From the aspect of administrative bodies and courts, a total of 384 measures were imposed in the observed period. The Tax Administration imposed the largest number of temporary restriction measures, with a share of almost 34% of the observed sample. Out of eight potential measures, the results of the research show that two measures of temporary restrictions are imposed in practice, of which the measure preventing the disposal of funds is present in 92.26% of cases. Starting from the main research question - Is there a positive influence of analysed measures to macroeconomic performance measured by GDP?, panel regression has been conducted on 1,276 observation units and results show that there is a positive relation between the number of issued measures of temporary restriction of entities from different sectors and the amount of Gross Domestic Product from 2017 to 2020 respectively.

The purpose of this paper is to indicate the potentials for tourism development based on the protected natural resources of the Republic of Serbia situated in the Moravica administrative district territory, the degree of their current utilization for the purposes of tourism and local population information on the above mentioned. Closed-ended survey was conducted (five-point scale) on the random sample of the residents in the urban part of the city of Čačak as the administrative center of the Moravica administrative district. The results are: 1) low degree of information among the local population, 2) medium (good) potential for tourism development, and 3) very low level of its utilization for tourism purposes. The results are also considered according to the natural resources protection type. The contribution of this paper is in the indication of potentially successful elements in future tourism offer for the entities in the field of tourism and hospitality.

The successful functioning and development of the capital market, along with the possibility of attracting new investments is largely contingent on the quality of financial reporting and the availability of the statements themselves. In view of the fact that the new Law on Accounting of the Republic of Serbia came into force, the question arises to what extent public companies respect legally prescribed deadlines for submitting their statements and by doing so do not commit an economic offense. The primary goal of this paper is to draw attention to the importance of a standardized and efficient legal framework that obliges public companies to publish financial statements in a timely manner. A survey was conducted that encompassed 416 public companies listed on the Belgrade Stock Exchange and their corresponding financial statements for 2018, as the reporting period. We tried to establish whether the sampled companies disclosed their statements within the deadline prescribed by the Law on Accounting (Law on Accounting, Official Gazette of RS, 62/2013, 30/2018). The results show that most companies disclosed financial statements during the period when they are still considered useful to potential and existing investors. Nevertheless, practice showed that there was room for improvement, and this was achieved with the adoption of the new Law on Accounting, which took effect on January 1, 2020. It integrates the deadline for compiling and disclosing statements, which in fact shortens the time period during which information on the companies' operations should be made available to the general public and potential investors.

Tourism represents the fastest growing branch of economy, which is focused on the realization of economic effects. In the previous period of tourism development, no account was taken of natural resources and the environment. Contemporary trends indicate the existence of a growing demand for preserved natural resources and ecologically clean environment. This trend has caused sustainable tourism development, which will establish a positive relationship between the tourism development and the preservation of the environment. This paper presents the fundamentals of sustainable tourism development. Serbia's mountain areas have a preserved potential of natural resources and the environment, which are the basis for the development of sustainable tourism. The aim of paper is to analyze the previous tourism development of mountain tourist destinations in Serbia, such as Kopaonik and Tara. The indicators of sustainable tourism are tested in this paper, and the results will show whether the previous tourism development in these areas was sustainable or unsustainable.

Under the influence of globalization and mass settlement of cities and urban areas, nostalgia for traditional and rural is increasingly felt. All this supports the development of manifestation and gastronomic tourism and the promotion of autochthonous products and traditions. Serbia is a country where a large number of national minorities lives, each of which has an impact on the gastronomy of the some area. The combination of all the cuisines and the diversity of tradition made Serbian dishes unique. There are a large number of events in the tourism offer of Serbia, which themes are gastronomic products. Manifestations, as a kind of promotion of a particular area, are becoming more and more popular. The paper analyses gastronomic manifestations as an important segment of Serbia's tourism offer. The methods applied in the paper are the method of correlation and comparative analysis. The results of the research indicate a positive interdependence between the number of manifestations and tourist traffic during the year, while the existence of an interdependence between the number of manifestations and tourist traffic in the regions was not recorded.

The purpose of this paper is to provide insight into the level of integration of the bioeconomy concept in the study programmes and modules at Serbian higher education institutions. Bioeconomy is based on multidisciplinary approach, which consists of research, education and innovation. Bioeconomy must be initiated by the government, developed by research institutions, universities and cluster, and thoroughly implemented into existing and emerging industries. As educators, Serbian universities should play a key role in developing future professionals. Research has been conducted to determine if Serbian universities educate students in the fields relevant to the concept of bioeconomy. All accredited study programmes in academic year of 2017/2018, at all universities in the Republic of Serbia, have been analysed. The research included 17 universities, 152 departments, 481 study programmes, 705 modules and 43,360 courses. The modules within the study programmes were categorised as bioeconomy-based modules, nonbioeconomy-based modules with at least one bioeconomy-based course, and non-bioeconomy-based modules. The research shows that of the total number of modules, 43% include one or more bioeconomy-based courses. The share of such courses within modules ranges from 1% to 21% and differs among groups of scientific fields.

Introduction. Periodontal diseases are associated with the presence of elevated levels of bacteria within the gingival crevice. Objective. The aim of this study was to evaluate a total amount of bacteria in subgingival plaque samples in patients with a periodontal disease. Methods. A quantitative evaluation of total bacteria amount using quantitative real-time polymerase chain reaction (qRT-PCR) was performed on 20 samples of patients with ulceronecrotic periodontitis and on 10 samples of healthy subjects. The estimation of total bacterial amount was based on gene copy number for 16S rRNA that was determined by comparing to Ct values / gene copy number of the standard curve. Results. A statistically significant difference between average gene copy number of total bacteria in periodontal patients (2.55.107) and healthy control (2.37.106) was found (p=0.01). Also, a trend of higher numbers of the gene copy in deeper periodontal lesions (>7 mm) was confirmed by a positive value of coefficient of correlation (r=0.073). Conclusion. The quantitative estimation of total bacteria based on gene copy number could be an important additional tool in diagnosing periodontitis. [Projekat Ministarstva nauke Republike Srbije, br. 175075]

Background/Aim. Previous investigations in many sports indicated that continued exercise, especially in hot environments, can cause high sweat rate and huge water and electrolyte losses, thus impairing the performance of athletes. Most these studies were conducted during training sessions, but rarely during an official competition. Therefore, the aim of our study was to determine pre- and post-competition hydration, fluid intake and sweat loss of young elite basketball players during the FIBA Europe U20 Championship. Methods. The study included 96 basketball male players, (19 ± 0.79 years) of eight national teams. Ambient temperature was 30 ± 2ºC, humidity 55 ± 4% and the mean playing time in game 18.8 ± 10.5 min. The following parameters related to hydration status were measured: fluid intake, urine output, sweat rate, percent of dehydration, urine parameters (specific gravity, color and osmolarity), body mass and body surface area. Results. We found that the mean fluid intake was 1.79 ± 0.8 L/h, sweat rate 2.7 ± 0.9 L/h, urine output 55 ± 61 mL and the percentage of dehydration 0.99 ± 0.7%. According to urine osmolarity more than 75% of players were dehydrated before the game and the process continued during the game. The difference in body mass (0.9 ± 0.7 kg) before and after the game was statistically significant. There were statistically significant correlations between the sweat rate and fluid intake, urine osmolarity, body mass loss, body surface area and percentage of dehydration. Fluid intake correlated with the percentage of dehydration, body mass loss, urine specific gravity and urine color. The sweat rate, which varied between the teams, was the highest for centers when this parameter was calculated on the effective time in game. Conclusion. Most of the athletes start competition dehydrated, fail to compensate sweat loss during the game and continue to be dehydrated, regardless what kind of drink was used. These results suggest that hydration strategies must be carefully taken into account, not only by the players, but also by the coaches and the team doctors.

Electronic and online communications are modern, and perhaps the most common form of communication between individuals and legal entities, and thus have become one of the most used ways of market communication. Viral marketing is evolving into the dominant form of marketing and exchange of information for the purpose of advertising, promoting, or achieving other goals. In this paper we present and analyse the phenomenon of viral marketing-its purpose, effects, and power of influence, and discuss it in terms of ethical and legal standards. Special emphasis is placed on the right to privacy and personal data protection, harassment, acting in good faith and in accordance with good business practices, the presentation of false or fraudulent information. The advantages and disadvantages of this type of marketing activity have been observed.

Introduction. Association studies have shown that gene polymorphisms in various classes of genes can modulate cancer risk. The -31G/C polymorphism in the promoter of survivin gene, affects the expression of the anti-apoptotic protein survivin which in turn may predispose an individual to some types of cancer. Objective. The aim of the study was to determine whether the survivin promoter -31G/C polymorphism could be a susceptibility factor for squamous cell carcinoma (SCC) of the oral cavity and basal cell carcinoma (BCC) of the skin. Methods. The DNA obtained from 88 patients with SCC, 60 patients with BCC and 111 healthy individuals was subjected to polymerase chain reaction-restriction fragment length polymorphism analysis (PCR- RFLP) in order to determine genotype and allele frequencies in patients and control groups. Logistic regression was used for cancer risk assessment. Results. The following distribution of genotypes was obtained: CC genotype 15% in the SCC group, 13% in the BCC group and 12% in controls; CG genotype 41% in SCCs, 35% in BCCs, 48% in controls; GG genotype 44% in SCCs, 52% in BCCs and 40% in controls. Allelic frequencies were as follows: G allele 0.65 in SCCs, 0.69 in BCCs and 0.64 in the control group; C allele 0.35 in SCCs, 0.31 in BCCs and 0.36 in the control group. There was no statistically significant difference in allele or genotype frequencies between the patients and controls (p>0.05). Conclusion. In Serbian population, -31G/C polymorphism in the promoter of the survivin gene cannot be considered as a risk factor for oral squamous cell carcinoma and skin basal cell carcinoma. [Projekat Ministarstva nauke Republike Srbije, br. 175075]

Sinanodonta woodiana (Lea, 1834), Chinese pond mussel (Bivalvia: Unionoida: Unionidae) is one of the most invasive aquatic macroinvertebrate species found in Europe. We report the Chinese pond mussel for the first time in Montenegro, in August 2012, in Lake Šasko (Adriatic part of the Central Mediterranean subarea). One specimen of the Chinese pond mussel was observed in a habitat with a predominantly silt-clay substrate. The main pathway of species introduction was evaluated to be via fish stocking. [Projekat Ministarstva nauke Republike Srbije, br. III 43002 i br. ON 173025]

Tumor necrosis factor (TNF) which exerts its effects through two different receptors known as TNF-R1 and TNF-R2, is a major proinflammatory cytokine involved in the pathogenesis of different types of tumors. We have investigated whether polymorphisms in TNF-alpha (-308G>A), TNF receptor 1 (36A>G) and TNF receptor 2 (676T>G) genes modulate the susceptibility for oral squamous cell carcinomas (OSCCs) and basal cell carcinomas (BCCs) of the skin, two frequent types of head and neck cancers. Genotyping was done on 50 OSCC patients, 50 BCC patients and 60 healthy individuals, using PCR/RFLP. A significant difference in genotype and allele frequencies was found between patients and controls for the TNF-R2 polymorphism, in both OSCC and BCC. There was no statistically significant difference between patients and controls for TNF-alpha and TNF-R1 polymorphisms. Carriers of G allele had an approximately 2.5- and 5-fold higher risk for OSCC and BCC, respectively, in the Serbian population.

Regenerative tourism is a new approach that seeks to establish and foster a symbiotic relationship between humans and nature based on the use of nature's ecosystem services (ESs) for people's improved quality of life and general wellbeing while promoting human contributions to the natural environment for the benefit of all. This research focuses on ESs as indicators of latent tendencies in the transformation from sustainable to regenerative tourism. The research was conducted in two cycles over a period of 11 years. The Participatory Rural Appraisal method (PRA) was used to gather information and local stakeholders' views concerning Serbia's Golija-Studenica Biosphere Reserve. Ninety-nine tourists were also interviewed face-to-face regarding their interests and demands. The research method included a Relative Frequency Citation index (RFC), which identified the ESs that respondents considered most important. The local stakeholders were unanimous in accentuating the importance of providing ESs that bring economic value, while tourists focused more on regulating or supporting cultural services. Our research methodology may serve as a benchmark for studies in other mountain tourism destinations and communities that are investigating developments towards regenerative tourism. [ABSTRACT FROM AUTHOR]

This study explores the impact of artificial intelligence (AI) on customer perceptions and behavior in restaurants, airline companies, and hotel sectors within the hospitality industry of Iran. The primary objective is to analyze how AI affects customer trust, brand engagement, electronic word-of-mouth (eWOM), and tourists' readiness to use AI technologies. Using a comparative analysis approach and surveys, this research tests hypotheses about the effects of artificial intelligence on various dimensions of customer interaction. The findings highlight significant relationships between the quality of artificial intelligence and customer engagement metrics, such as trust and brand loyalty, which are crucial for understanding and predicting customer behavior in response to technological advancements. This study lays the groundwork for theoretical assumptions about sustainability in these sectors in developing countries, providing a basis for future empirical research that could validate these assumptions and explore broader implications of AI integration in enhancing sustainable practices within the hospitality industry. [ABSTRACT FROM AUTHOR]

The surfaces of natural (NZ) and zeolite/iron oxyhydroxide composite (ZFe) samples were analysed by means of inverse gas chromatography (IGC) using the adsorption data of organic non-polar and polar probes, in the infinite and finite-dilution regimes, in the temperature range 483-513 K. The dispersive components of the free energy of adsorption, S, determined by the Gray method, decreased with increasing temperature for both zeolites. The specific interactions were characterised by the specific free adsorption energy change, Ga S, the specific enthalpy change of adsorption, Ha S, as well as the donor and acceptor interaction parameters (KA, KD) and the basic character of the NZ and ZFe was evidenced. The adsorption isotherms of n-hexane, benzene, chloroform and tetrahydrofuran (THF) were determined under finite surface coverage and used to estimate the specific surface area and the adsorption energy distribution. The adsorption capacity of the ZFe was higher than for NZ for all the investigated adsorbates. The specific surface areas and pore size distributions were also determined using nitrogen adsorption-desorption isotherms, i.e., the BET method. It was observed that the nature of the adsorbate and the properties of the solid surface of the initial and modified samples governed the uptake of adsorbates. [ABSTRACT FROM AUTHOR]

Searching for rural, intact areas out of cities during the COVID-19 crisis, tourists brought renewed interest in consuming traditional food based on wild edible herbs/natural products. Increased interest in local herbal potentials could be a driving force in modelling rural destinations to enrich food tourism offers and provide a new experience. This study aimed to assess the relevance of ethnobotany and traditional knowledge on wild herbs utilization with a focus on increased demand for natural products as a basis for future food tourism offer creation in rural areas. By applying free-listed observations and semi-structured ethnobotanical interview approach data were obtained (n = 169) and quantitatively analyzed using indices of Relative Frequency Citation (RFC), Use Value (UV) and Pearson Correlation Coefficient (PCC). The final results were visualized using the Venn diagram and DIVA-GIS. The results indicate subtle transformation in food tourism demands and new trends in nutrition based on 34 species divided into 7 functional groups along the geographic gradient. Traditional food systems through reviving ethnobotanical knowledge and practices should be a matter of future food tourism management. [ABSTRACT FROM AUTHOR]

Copyright of MB University International Review - MBUIR Journal of Theory & Practice is the property of University MB / Univerzitet MB and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Vaccine Conspiracy Beliefs Scale (VCBS) is a widely used measure of conspiracy beliefs about vaccines, but evidence of its validity and measurement invariance, especially in youth samples, is still largely missing. The present study examined VCBS scores' factor structure, measurement invariance, convergent and discriminant validity, and incremental predictive validity. A sample of 803 Serbian youths (age range 15–24; 59.2% females) was recruited for the study. A modified single-factor model of the VCBS was supported, and showed evidence of full scalar invariance across gender, age, vaccination status, and personal history of COVID-19. Evidence of the VCBS scores' convergent and discriminant validity was obtained by examining associations with general conspiracy beliefs, vaccination attitudes, vaccination knowledge, intentions to get vaccinated against COVID-19, paranoia worries, fear of injections and blood draws, importance of God, self-rated health, and self-rated family's financial situation. The VCBS scores predicted a unique variance in the intention to get vaccinated against COVID-19, over and above vaccination attitudes and vaccination knowledge. The results suggest that the VCBS is a valid measure of vaccine conspiracy beliefs in youth. [ABSTRACT FROM AUTHOR]