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Introduction/purpose: Gunpowder is a type of explosive material (EM), a mixture of chemical compounds capable of releasing their potential energy in a very fast exothermic chemical reaction. This paper investigates the single base gunpowder samples. Methods: Microcalorimetry (MC), or heat flow calorimetry (HFC), is the only modern method that monitors the direct cause of autoignition - the rate of heat release, which is a key factor for gunpowder storage explosive safety. It is based on high-sensitivity calorimeters which allow monitoring of chemical reactions at low speeds. The microcalorimeter "TAM III" was used and the method given by the NATO standard STANAG 4582. A very reliable result was obtained on the chemical stability of the observed single base gunpowder samples, as well as an assessment of its behavior in the next 10 years. Results: The thermal activity of gunpowder depends on several factors, the most important of which are: chemical composition, size and shape of the gunpowder grain, the degree of decomposition of the gunpowder, storage conditions, etc. Namely, it is a much more exact and consistent indicator of the chemical stability of gunpowder compared to the critical diameter. Conclusion: The MC method should be used both for monitoring the chemical stability of gunpowder during storage and for the prediction of the service life of gunpowder.

Abstract The WWE domain is a relatively under-researched domain found in twelve human proteins and characterized by a conserved tryptophan-tryptophan-glutamate (WWE) sequence motif. Six of these WWE domain-containing proteins also contain domains with E3 ubiquitin ligase activity. The general recognition of poly-ADP-ribosylated substrates by WWE domains suggests a potential avenue for development of Proteolysis-Targeting Chimeras (PROTACs). Here, we present novel crystal structures of the HUWE1, TRIP12, and DTX1 WWE domains in complex with PAR building blocks and their analogs, thus enabling a comprehensive analysis of the PAR binding site structural diversity. Furthermore, we introduce a versatile toolbox of biophysical and biochemical assays for the discovery and characterization of novel WWE domain binders, including fluorescence polarization-based PAR binding and displacement assays, 15N-NMR-based binding affinity assays and 19F-NMR-based competition assays. Through these assays, we have characterized the binding of monomeric iso-ADP-ribose (iso-ADPr) and its nucleotide analogs with the aforementioned WWE proteins. Finally, we have utilized the assay toolbox to screen a small molecule fragment library leading to the successful discovery of novel ligands targeting the HUWE1 WWE domain.

Introduction/aim: This paper aims to present the methodology for creating educational content/scenarios on a ship simulator (bridge simulator) that will serve officers of river units in developing the ability to react when performing regular and military tactical tasks on the ships of the River Flotilla. Also, training on the simulator aims to train officers of river units using modern information technologies. Methods: The paper uses simulation methods, experimental methods, case studies, and operational research. Results: Specific educational content/scenarios were created, also specific methodology was developed and the principles were clearly defined according to which content/scenarios are created on the ship simulator. Conclusion: By using the ship simulator, in different teaching scenarios, cadets of river units as well as members of river units are trained and acquire the ability to react adequately in real situations in the shortest possible time.

Abstract Background Single limb support phase of the gait-cycle in patients who are treated for a pertrochanteric fracture is characterized by transversal loads acting on the lag screw, tending to block its dynamization. If the simultaneous axial force overcomes transversal loads of the sliding screw, the dynamization can still occur. Methods Biomechanical investigation was performed for three types of dynamic implants: Gamma Nail, and two types of Selfdynamizable Internal Fixators (SIF) – SIF-7 (containing two 7 mm non-cannulated sliding screws), and SIF-10 (containing one 10 mm cannulated sliding screw). Contact surface between the stem and the sliding screws is larger in SIF implants than in Gamma Nail, as the stem of Gamma Nail is hollow. A special testing device was designed for this study to provide simultaneous application of a controlled sliding screws bending moment and a controlled transversal load on sliding screws (Qt) without using of weights. Using each of the implants, axial forces required to initiate sliding screws dynamization (Qa) were applied and measured using a tensile testing machine, for several values of sliding screws bending moment. Standard least-squares method was used to present the results through the linear regression model. Results Positive correlation between Qt and Qa was confirmed (p

Earthquakes are a rather complex natural phenomenon that cannot be prevented, and their effects can be catastrophic and have profound implications on various economic sectors (especially tourism). This study investigates the relationships between subjective factors (gender, age, education, previous experience, and disaster anxiety), the perceived travel risk, and the travel intention of tourists from Serbia to destinations in Türkiye. The pilot study was done in March 2023 with 110 respondents from the Faculty of Science, Department of Geography, Tourism, and Hotel Management, Novi Sad. After the validation of the instruments, the main survey was conducted in the period from March to June 2023. The subjects of interest were residents of Serbia over the age of 18. The data from this study are analyzed using the confirmatory factor analysis and path analyses. This study aims to enhance the understanding of perceived risk and travel intention, specifically focusing on Türkiye. The assessed outcome relates to how tourists perceive three specific categories of risk when traveling to destinations with a high risk of natural disasters, such as earthquake-prone areas. The findings suggest that older respondents tend to perceive lower physical and financial travel risks, even though the influence of age on the perception of socio-psychological risks was inconclusive. Further results reveal that individuals with prior experience tend to hold a heightened perception of physical, financial, and socio-psychological risks. An examination of the relationship between disaster anxiety and perceived travel risks indicates that physical, financial, and socio-psychological risks exert a negative influence on travel intention. Thus, this study may provide a conceptual foundation for both theoretical and practical implications for the improvement of risk management techniques at a specific travel destination in areas prone to earthquake hazards.

The paper analyzed 16 ports on the Danube that are part of the Trans-European Transport Network with the aim of calculating their efficiency, using the DEA method. The indicators included in the analysis, which represent the input indicators, are the number of operators, the total port area, the maximum depth of the river in the observed port, the number of terminals, the length of the quay, the maximum capacity of the anchorage area, and the storage capacity, while the output indicator is the amount of cargo handled. The results of the analysis showed that out of 16 analyzed ports, 6 ports are efficient, which enabled further evaluation of efficient ports using SWARA and WASPAS methods. After the analyze, the port that is ranked as the best is the port of Giurgiu, which has the largest number of operators and the largest number of terminals. The port of Dunajvaroš has the lowest efficiency, because of the smallest storage capacity and the smallest port area. The testing of the developed model showed the exceptional convenience of its practical application. The contribution of the paper is distinguished by the development of a model that is unique in terms of methods and variables included in the calculation.

Numerous research studies on composite solder materials have aimed to develop sustainable lead-free solders. The production of various types of lead-free solders has been seriously investigated worldwide as an alternative to harmful Pb solders. The study examined the influence of graphene nanoparticles on the microstructure, density, and microhardness of lead-free Sn-0.7Cu solder. Graphene was used in the form of graphene nano-sheets (GNSs) with variable weight content and the nano-composite solder was obtained by powder metallurgy method. The purpose of the study was to utilize reinforcement to improve the physical and mechanical properties of solder materials. It was observed that the GNS particles were evenly distributed along the grain boundaries, resulting in a finer dendritic b-Sn structure and higher microhardness values. The addition of GNS particles to the Sn-0.7Cu solder matrix increased the microhardness values by 15%, while the density of the composite solder was slightly reduced.

This paper presents research on the changes in the mechanical and structural properties of the commercial aluminum alloy EN-AW 7075 during thermomechanical processing. The processing involved artificial aging of the alloy at a temperature of 150°C for 30 minutes, followed by cold rolling after aging. Changes in hardness and impact toughness during the experiment were monitored. Hardness was measured using the Leeb method, while impact toughness was measured using the Charpy method. In the annealed state, the lowest hardness values were recorded, while the highest-impact toughness value was achieved in the as-quenched state. By applying cold plastic deformation after artificial aging, the hardness of the alloy significantly increased, while the impact toughness continuously decreased. After deformation of 20%, cracks appearance prevented further deformation. Optical microscopy was used to follow microstructural changes during the applied processing regime. Precipitates of various sizes and morphologies were observed in the structure. The annealed state results in poorly defined grain boundaries and formation of large precipitates relatively evenly distributed throughout the matrix. Cold plastic deformation after aging has resulted in elongated grain structure aligned with the rolling direction, along with crushing of secondary phase particles.

Research of uvological characteristics is one of the obligatory steps for determination of general production and technological value of grapevine varieties. Such research is particularly recommended for local varieties that did not previously show sat­isfying characteristics necessary for production of high-quality wine. Local grapevine varieties Smederevka (white wine variety) and Žametovka (red wine variety) have mostly served for production of low-quality wine in the past. With changes in the manner of pro­duction in the sense of focus on high-quality wine and production of wine with geograph­ical indications, vineyards planted with these varieties in Serbia have mostly been grubbed up. However, due to the characteristic and favourable terroir conditions, they have survived in the Trstenik wine-growing district (subregion within the Tri Morave wine-growing re­gion). With the aim of determining uvological characteristics of these two varieties in current climate conditions that are favourable for these high-yield varieties, this paper examines the mechanical composition of grape bunches (bunch weight, number of berries, stem weight), mechanical composition of berries (weight of 100 berries, weight of skin of 100 berries, weight of mesocarp of 100 berries and weight of seeds of 100 berries), as well as grape must characteristics (sugar content and total acids in grape must) of representative genotypes of local varieties Smederevka and Žametovka in production vineyards in the Trstenik wine-growing district. Research results have shown that uvological characteristics of these varieties are slightly better in comparison with previous research carried out in other wine-growing areas, that is, in comparison with general information from literature, which indicates the necessity for further research of these varieties in different agro-eco­logical conditions.

This study investigates the perception of the implementation of the Farm to Table (F2T) concept on the sustainability of agritourism households in the Republic of Serbia. The main objective of the study is to determine how this concept affects the environmental, economic, and social sustainability of these households according to the participants. Data were collected through surveys of agritourism homestead owners in the regions of Vojvodina, Western Serbia, Southern Serbia, and Eastern Serbia. The research findings, obtained using quantitative (SEM) analyses, indicate that the F2T concept significantly contributes to the sustainable development of agritourism homesteads by increasing economic profitability, reducing environmental impact, and strengthening the social community. Moderators such as seasonal product availability, employee education, and the local community support have a significant impact on the effectiveness of F2T activities. The innovation of this study lies in the application of quantitative methods to analyze the specific impacts of the F2T concept on the sustainability of agritourism households, an area that has been poorly explored in the literature. The study has a number of implications, including providing empirical data that can help farmers, tourism operators, and policymakers to promote sustainable agritourism businesses.

Prion diseases are neurodegenerative disorders caused by misfolded prion proteins. Although rare, the said diseases are always fatal; they commonly cause death within months of developing clinical symptoms, and their diagnosis is exceptionally difficult pre-mortem. There are no known cures or treatments other than symptomatic care. Given the aggressiveness of prion diseases on onset, therapies after disease onset could be challenging. Prevention to reduce the incidence or to delay the disease onset has been suggested to be a more feasible approach. In this perspective article, we summarize our current understandings of the origin, risk factors, and clinical manifestations of prion diseases. We propose a PCR testing of the blood to identify PRNP gene polymorphisms at codons 129 and 127 in individuals with familial PRNP mutations to assess the risk. We further present the CRISPR/Cas9 gene editing strategy as a perspective preventative approach for these high-risk individuals to induce a polymorphic change at codon 127 of the PRNP gene, granting immunity to prion diseases in selected high-risk individuals, in particular, in individuals with familial PRNP mutations.

Las novelas Ubik y The Man in the High Castle, de Philip K. Dick, exploran la idea de la multiplicidad de las realidades, que pueden entenderse mejor si se interpretan desde un punto de vista cosmológico. Los principios científicos de decoherencia, tal como los formularon H. Dieter Zeh y Hugh Everett III, arrojan luz sobre la naturaleza de tales mundos ficticios, su creación y disolución y su percepción, tanto por los protagonistas como por el lector. Los rompecabezas ontológicos del mundo cuántico, basados en el rechazo del estatus especial de un observador en la realidad física y del ramaje fractal del universo, ayudan a percibir los mecanismos en funcionamiento en ambas novelas. La decoherencia puede ser la clave para comprender las fronteras en proceso de desintegración entre las realidades de las dos novelas, que se manifiestan como mundos en superposición. Sin embargo, las reglas de este principio científico son puestas radicalmente en duda por la eclosión de lo que podría llamarse los agentes de la recoherencia. Tales agentes revelan la existencia de realidades alternativas en las novelas, así como el proceso de la violación del principio de decoherencia. Estas manifestaciones no solo resultan de interés tanto desde un punto de vista científico como artístico, sino que asimismo revelan las realidades en las novelas como mucho más coherentes de lo que aparentan superficialmente y son interpretables como paralelos literarios a los experimentos mentales concebidos como posibles explicaciones de la teoría cuántica del mundo. Palabras clave: Philip K. Dick; Ubik; The Man in the High Castle; decoherencia; recoherencia; ciencia ficción; multiverso Philip K. Dick's novels Ubik and The Man in the High Castle explore the idea of the multiplicity of realities, which can be understood better if interpreted from a cosmological point of view. The scientific principles of decoherence, as formulated by H. Dieter Zeh and Hugh Everett III, shed light on the nature of these fictional worlds, their creation and dissolution and their perception by both the protagonists and the reader. Ontological puzzles of the quantum world, based on the rejection of the special status of an observer in physical reality and fractal branching of the universe, offer insights into the mechanisms at work in these two novels. Decoherence may be the key to understanding the disintegrating borders between realities in both novels, which are manifested as worlds in superposition. However, the rules of this scientific principle are radically challenged by the emergence of what could be termed the agents of re-coherence. These agents reveal the existence of alternate realities in the novels, as well as the process of the violation of the decoherence principle. Not only are these occurrences interesting from both a scientific and artistic point of view, they also reveal the realities in the novels as being far more coherent than they seem on the surface and interpretable as literary parallels to thought experiments conceived as possible explanations of the quantum world theory. Keywords: Philip K. Dick; Ubik; The Man in the High Castle; decoherence; recoherence; science fiction; multiverse, Philip K. Dick's Decohering and Recohering Worlds: The Cases of Ubik and The Man in the High Castle I. Introduction The reader is willing to accept the fictional worlds as [...]

Introduction/purpose: The activity of managing the budget funds of the Ministry of Defense and the Serbian Armed Forces (MoD and AF) does not accept even minimal mistakes in the procurement of weapons and military equipment (WME). Equipping the Serbian Armed Forces with weapons and military equipment must be economically justified because a large part of the budget is allocated for that purpose. The goal of the research is to look at the economic aspect of treating costs as a prerequisite for the process of equipping the defense system with weapons and military equipment. Methods: For the purposes of the research, we used analytical and descriptive methods in order to see the comprehensive costs of assets that precede the effective equipping of the Ministry of Defense and the Armed Forces with WME. The research included the analysis of 18 review and research papers, which we analyzed in accordance with the Rulebook on equipping the Serbian Armed Forces with weapons and military equipment. Results: The results of the research indicate that economic justification is expressed implicitly by the ratio of intangible benefits and achieved goals to the invested funds. The most common reason why economic justification is not expressed explicitly by the difference between the initial investment and the final asset quantity is the existence of a number of circumstances for making wrong investment decisions. Also, if the costs are not considered in detail during the entire life cycle of the investment, it can be assumed that the planned target result is not certain. Conclusion: The research indicates that not considering costs during the entire life cycle of the investment is the main reason for unplanned investments in the later stages and the emergence of numerous problems in the functioning of the defense system.

Philip K. Dick’s novels Ubik and The Man in the High Castle explore the idea of the multiplicity of realities, which can be understood better if interpreted from a cosmological point of view. The scientific principles of decoherence, as formulated by H. Dieter Zeh and Hugh Everett III, shed light on the nature of these fictional worlds, their creation and dissolution and their perception by both the protagonists and the reader. Ontological puzzles of the quantum world, based on the rejection of the special status of an observer in physical reality and fractal branching of the universe, offer insights into the mechanisms at work in these two novels. Decoherence may be the key to understanding the disintegrating borders between realities in both novels, which are manifested as worlds in superposition. However, the rules of this scientific principle are radically challenged by the emergence of what could be termed the agents of re-coherence. These agents reveal the existence of alternate realities in the novels, as well as the process of the violation of the decoherence principle. Not only are these occurrences interesting from both a scientific and artistic point of view, they also reveal the realities in the novels as being far more coherent than they seem on the surface and interpretable as literary parallels to thought experiments conceived as possible explanations of the quantum world theory.

Local markets have been a special setting throughout human history. Apart from their important social role, they had immeasurable economic importance as primary forms of exchange of goods (trade). Nonetheless, they experienced numerous transformational changes that affected their functioning. Like other countries, Serbia has a long tradition of market activity. However, several novelties have been introduced in recent years. Among many, the process of e-fiscalization is the main issue. Therefore, the focus of our research is based on a qualitative analysis of online media content (news and comments) related to the fiscalization of market activity. The attitudes of different categories of participants (state authorities, vendors, and customers) were analyzed. LIGRE open-access software was used for this purpose. The results of the analysis showed conflicting parties. Legislators emphasize the exclusive positive effects, while vendors point to the negative side of fiscalization. As a third party, customers (service users) have an undefined attitude in relation to fiscalization (pros/cons/neutral). There is an agreement to introduce market activity into legal flows. However, the key prerequisite is the prior resolution of a number of problems (working conditions, business costs, market monopoly, etc.).

Experimental investigations of the effectiveness of the pretreatment of the acid leaching process of a representative sample of electric arc furnace dust (EAF dust) and characterization of a representative sample were performed. As EAF dust is globally defined as hazardous solid industrial waste, and it contains a high percentage of zinc and other useful components, in this paper, the application of pretreatment will be carried out in order to increase the efficiency of the further process of acid leaching, all with the aim of using EAF dust as a secondary raw material for metal valorization. The pretreatment involved the application of a simple process of leaching the EAF dust sample with distilled water. Under the following defined optimal leaching conditions: time—30 min, ratio of solid to liquid phase—1:10, temperature—ambient, and stirring speed—500 rpm, a reduction in the content of water-soluble components was achieved, namely, 83% Cl, 92% K, 74% Na, 14% Cd, 15% Ca, and 19% F. The application of the pretreatment enables significantly better filtration of the suspension and increases the leaching efficiency of zinc and other useful components in the further process of leaching EAF dust with a sulfuric acid solution, compared with the process of direct acid leaching of EAF dust.

Purpose – During the pandemic, two types of fear were identified that occur significantly in all groups or profiles of people. The aim of this paper is to determine which of the two types of fears exist in certain psychological groups, and which of the fears strongly influence the decision to travel. Design/methodology/approach – The VALS 2 method and standardized questionnaire were used for the segmentation of the tourist market or for the determination of the psychographic profiles of the consumers, and three additional questions were joined to it as they were vital for the research of the type of fear and its impact on the decision for traveling. When the reliability of the questionnaire and the validity of the sample were determined, the data were further processed using a computer program package IMB AMOS SPSS 21.00, and then, based on the theoretical suppositions and hypotheses, the SEM structural model was created. Findings – The paper indicates the existence of established types of fears in humans, when it comes to pandemics and similar crisis situations. People are most afraid of infection during travel, and lack of funds and job loss during the critical period of the pandemic. The research conducted confirms that all groups of people, who are determined by the psychological technique VALS 2, react with a certain dose of fear and make decisions under the pressure of fears. Research limitations/implications – The research had limitations in terms of contact with people and conducting live surveys. The measures during the pandemic, which were carried out by the state, included social distance and limited movement of people. Practical implications – The work can contribute to the community, along with similar research. The results of the research will be available, and it will be possible to see the behavior of people during crisis situations, and the impact of fears on making decisions, both travel decisions and decisions related to other areas of life. Originality/value – The paper provides research results on a large sample of respondents, and can serve as a basis for further research in the field of tourism, psychology and similar fields. It is crucial to consider the type of fears, and the strength of the impact of these fears on the decision to travel, during crisis situations.

A recent proposal for a new kind of astroengineering artifact due to Vukotić and Gordon (2022) is discussed, in particular in light of multiple benefits offered by the magnetic Penrose process. It is argued that constructing a large number of artifacts of this kind is sufficiently strongly motivated for any advanced extraterrestrial society that their statistical weight in the set of all technosignatures will be significant. This will, in turn, have important consequences for our practical SETI/search for technosignatures projects.

Purgatio or emendatio morae would in the literal translation into English mean purging the default. In Roman classical law, it amounted to the possibility of the debtor in default, firstly, to fulfil the primary obligation and, secondly, to remediate potential legal effects of the consequences of mora debitoris. There were other ways of purging the default as well. As a consequence of emendatio morae, debtor's obligations, both primary and secondary ones, would cease to exist and the consequences of mora debitoris would cease to produce legal effects. Therefore, purgatio morae consisted of two elements: debtor's offer to completely fulfil the prestation owed as well as his offer to remediate the legal effects of the consequences of the default.

The initial research question in this paper is whether the predispositions for the evaluation of contemporary monumental culture in the city can be determined in the context of heritological research. In order to reach a possible answer, it is necessary to first determine the meaning of the word 'monument', and then present the dominant interpretations of what makes a 'good' monument. Thus, the paper starts from abstracted experiences concerning the place of monuments in the urban structure, then pays attention to issues of material, shape, and meaning, as well as multiple identities of monuments in the city. Finally, the basic theoretical starting points for the valorization of monuments are determined, which point out the relationship between commemorative values, monumental identities, and urban structure. The aim of this paper is to offer a synthesis of the heritological approach, which could then serve as a model for the analysis of contemporary monumental culture in the city. We can express this approach in the following way: the city is viewed as a heritage corpus, as a function of the relationship of material, form and meaning that is associated with its identities (conceptual, factual, and actual). Hence the initial answer to the question of what the city is through the prism of heritology: the city is a heritage corpus that evokes the maximum of memory in a minimum of space. What would then be a monument-in-a-city? The monumentin-the-city is a point of high commemorative value, an element that activates the memory potential of the urban structure. Thus, we get a basis for answering the question of what makes a 'good' monument: a good monument is one that satisfies the requirement of intensive commemorativeness (ie communicativeness of memory contents) in the city, while a 'bad' monument is what is insufficient in the mentioned sense.