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The paper presents the results of research dealing with the influence of climatic factors on the size of earlywood and latewood and the total diameter increment of incense-cedar (Calocedrus decurrens (Torr.) Florin). Samples taken from 30 trees at a height of 1.3 m were used in the analysis. The values were correlated with the mean monthly air temperature and precipitation sums (from April to September). In addition, the tree age expressed in years was included as an important factor. The analysed parameters explained 64.8% of the current diameter increment, 64.8% of the latewood, and 55.8% of the earlywood share.

Apple and beetroot pomace flour (APF and BPF), along with two sweeteners, sucrose and a blend of sucrose substitutes (erythritol, stevia, inulin, and fructose), were simultaneously incorporated into three matrices formulated with agar, pectin, or gelatin as gelling agents. The aim was to produce jelly candies with high content of dietary fiber and dietary phenolics, and reduced energy value. The simultaneous incorporation of sucrose substitutes and pomace flour resulted in decrease of Carb:Fiber and Sugar:Fiber Ratio to extremely low values of 2.7–3.4 and 1.3–1.6 respectively, as well as in Energy:Fiber Ratio decrease to 9.2–12.3 kcal/g DF. Relative Antioxidant Capacity Index (RACI), as indicator of antioxidant potential, was calculated by assigning equal weight to Folin–Ciocâlteu, DPPH and FRAP assays applied upon in vitro digestion of 18 formulations of jelly candies. Results obtained for formulations with and without sucrose, as well as with and without APF or BPF, enabled insight into effects of pomace flour addition and sucrose substitution in each gelling matrix on functional properties. The incorporation and the substitution impact on postprandial glucose response were followed in vivo. Their superimposing resulted in glycemic index below 30 and low glycemic load. Efficiency of applied approach in functionalization of confectionery burden with energy and minimization of glucose spike represent an example of agro-residues re-introduction with the highest potential contribution to anti-obesity strategy.

Adding blockages to the gas flow channels in the bipolar plates has a significant effect on the performance of the proton exchange membrane fuel cell (PEMFC). The design parameters of the gas flow channels with blockages mainly include the blockage shape (S), blockage number (N), blockage height (H), and channel–rib width ratio (CRWR) value. This paper systematically examines the combined effects of S, N, H, and CRWR value on current density (I), pressure drop (ΔP), net output power (Wnet), and non-uniformity of oxygen distribution (NU) of PEMFC through the application of the orthogonal experimental method (OEM). To provide a comprehensive optimization strategy, a novel multi-criteria decision framework is introduced, which integrates the analytic hierarchy process (AHP) and entropy weight method (EWM) to balance different evaluation objectives. Results from the AHP-EWM analysis reveal that the weight values of I, ΔP, Wnet, and NU are 0.415, 0.08, 0.325, and 0.18, respectively. The CRWR value exhibits the greatest effect on the comprehensive performance of PEMFC, followed by H, N, and S. The optimal design parameter combination identified in this paper is a triangular blockage with nine blockages, a height of 0.8 mm, and a CRWR value of 0.25, corresponding to the highest comprehensive score of 31.8306 among the 25 groups of orthogonal experiments. This paper provides a new optimization perspective and certain guidance for the performance optimization direction of PEMFC.

The deepening geopolitical conflict between the West and the Russian Federation, intensified by the war in Ukraine, has caused significant changes in the security environment of the Republic of Serbia and has largely complicated the realization of its national and defense interests. Military neutrality, as an important defense interest and key security commitment, is also conditioned by changes in the security environment of the Republic of Serbia, as well as vital national interests such as the preservation of territorial integrity, the prospect of EU membership, and ensuring energy security. Therefore, the subject of research in this paper represents the relationships of connectivity and conditioning of the military neutrality of the Republic of Serbia, key changes in the security environment caused by the war in Ukraine, and the mentioned vital national interests. The paper starts from the hypothetical stance that changes in the security environment of the Republic of Serbia complicate the realization of the military neutrality policy, especially in relation to the mentioned vital national interests. The analysis of these connections and relationships is based on the theoretical postulates of the realist school of international relations, according to which great powers and other international actors use all available instruments for projecting power and achieving interests in an anarchic system. In changed geopolitical circumstances, the military neutrality policy of the Republic of Serbia, based on balanced cooperation with the parties in the Ukrainian conflict, is becoming increasingly difficult to maintain, as there is a serious "coercive" potential of the mentioned parties, related to the vital national interests of the Republic of Serbia, such as EU membership, preservation of territorial integrity, and energy and economic security of the Serbian state and society. The methodology in the research is based on the analysis of relevant sources and literature.

Phenotypic plasticity refers to the ability of genotypes to exhibit different phenotypes in response to environmental conditions. The AMMI model is often used to analyze this interaction in multienvironment trials. In a study involving six tomato genotypes grown in different environments, genotype L88 yielded the highest average at nearly 31 t/ha, while L27 and L53 had the lowest yields. The AMMI biplot indicated that genotypes L49 and L21 had strong interactions with the Pazardzhik environment, while L88 had a positive interaction with the Požega environment. The analysis concluded that AMMI is effective for assessing trait stability in multienvironment trials.

Silicon nitride (Si3N4) with high thermal conductivity is one of the most promising substrate materials for the next-generation power devices. There are several ways to improve thermal conductivity of Si3N4. Substantially higher thermal conductivities for the Si3N4 ceramics could be attained by reduction of lattice oxygen content or by the increasing the ?/? phase ratio during nitridation thus enhancing grain growth during post-sintering. The method of purification of the grains and decreasing the two-grain junction films by adding large ?-Si3N4 grains to the raw Si3N4 powder, seeding by grain growth of Si3N4 crystals in polycrystalline ceramics also improves thermal conductivity. High thermal conductivity can be further achieved by development a textured micro-structure in which elongated ?-Si3N4 grains are oriented almost unidirectional. This paper summarizes the extrinsic factors governing the thermal conductivity of Si3N4 ceramic regarding micro-structural parameters such as lattice defects in single-crystal, sintering additives, change in microstructural parameters like ?/? ratio, grain size, aspect ratio, grain orientation and the morphology, composition of grain-boundary, secondary phases, processing method.

Southeastern Europe (SEE), which includes Serbia, along with Germany and Poland, is one of the largest producers of solid fuels in Europe. Despite growing environmental concerns, coal, especially lignite, persists and remains the dominant fuel for electricity generation in this region. Concurrently, these power plants emerge as the predominant emitters of pollutants in all the observed states. To conduct a comprehensive analysis, data on major emitters within the EU were gathered, allowing for a detailed comparison with SEE countries. A specific focus was placed on the thermal power plant Kostolac in Serbia, where the calculation of SO2 emissions for two thermoblocks was undertaken. Comparisons were drawn with emitters in EU countries, with a particular emphasis on SEE nations. The analysis involved data from wells that have undergone excavation over specific periods, facilitating an exploration of the correlation between calculated values, those from exploited wells, and projections of future SO2 emissions from new wells in areas earmarked for surface mining exploitation.