The avocado seed is a non-edible part of the fruit that is typically discarded as waste; yet it has valuable phytochemicals. A phytochemical screening of the aqueous extract from avocado seeds was conducted under controlled experimental conditions using standard methods. The results indicated the presence of flavonoids, saponins, terpenoids, eugenols, tannins, phenolics, glycosides, and alkaloids while steroids were absent. Zinc oxide nanoparticles (ZnO NPs) were synthesized from the avocado seed aqueous extract using zinc acetate as a precursor. The biosynthesized NPs were characterized using X-ray diffraction (XRD), which confirmed their hexagonal wurtzite crystalline structure. The XRD analysis revealed an average crystallite size of 29.876 nm for the ZnO NPs. These ZnO NPs were subsequently tested as antibacterial agents against Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa). The biogenic ZnO NPs exhibited an inhibition zone of 20 mm against S. aureus; therefore, indicating its usefulness in the pharmaceutical sector.

In this article, we contribute to the special issue of the Kragujevac Journal of Science devoted to the International Year of Quantum Science and Technology (IYQ2025). We discuss several connections between Quantum Theory and Modern Cosmology. We begin with a brief overview of the major theoretical discoveries of Quantum Theory and Quantum Mechanics, proceed to Quantum Field Theory (QFT), and conclude with aspects of modern, quantum cosmology.

The answers on the current status and future development of Quantum Science and Technology are presented.

Quantum Machine Learning (QML) integrates two prosperous scientific fields: quantum computing and artificial intelligence. We will review recent developments in QML-based methods, their theoretical foundations, algorithmic progress, practical applications, and remaining issues. By analyzing contemporary QML literature, we will identify its main strengths and weaknesses that guide the pursuit of achieving quantum advantage in machine learning tasks.

In the past decade, multiple incidents have been documented involving the presence of venomous snakes in urban regions of Serbia, where these animals are typically absent. We analyzed the confirmed cases in major cities such as Belgrade, Novi Sad, Niš, Kragujevac, and Kraljevo, along with occurrences in smaller towns. The snake species involved was the nose-horned viper (Vipera ammodytes), which often "hitchhikes" vehicles returning from nature; the alternative - escaped captives - was highly improbable. These incidents most often ended with no bites to humans. Public reactions usually included fear and panic. Successful interventions by experts from faculties, institutes, or local snake handlers prevented bites or the establishment of breeding populations in urban areas. We addressed the ecological impacts of habitat disruption/urbanization, shifts in biodiversity, and interactions between humans and wildlife. Ongoing monitoring, public education, and establishment of educated communal services and response protocols are essential to reduce risks to both humans and these protected reptiles.

In the reaction of vanillin and acetone under Claisen-Schmidt conditions, dehydrozingerone, a very attractive biologically active compound, is obtained. This compound served as a starting material for the synthesis of O-alkyl derivatives which further react with hydrazine hydrate in formic acid, yielding a new series of N-formyl pyrazolines. All new products were identified and well characterized by IR, 1H NMR, and 13C NMR spectroscopy. An ADME study was performed to investigate the pharmacokinetic properties of the synthesized derivatives. The preliminary in vitro cytotoxic activity of pyrazolines against the human cervix adenocarcinoma cell line (HeLa) was evaluated using the MTT method. Among the series, compounds 3c, 3d and 3f showed the most promising cytotoxic activity. Morphology changes of HeLa cells treated with selected compounds were visualized and compared with that of the control.

Quantum chemical approach was used to study four different types of interactions of electron-rich and electron-deficient arenes with alkali cations and halide anions. Cation-π and C-H···anion interactions of benzene, as well as anion-π and C-F···cation interactions of hexafluoro benzene, were studied by the means of two methods of energy decomposition analysis - Symmetry Adapted Perturbation Theory (SAPT) and Extended Transition State - Natural Orbitals for Chemical Valence (ETS-NOCV). Thorough analysis showed that these decomposition methods identify induction/orbital interactions as the most dominant component of interactions with cations, while electrostatic component is the dominant one in the systems containing anions. Minor disagreements were observed in the cases of interactions with larger ions (K+ and Br-). Overall, SAPT and ETS-NOCV are in good agreement for interactions that include cations. Caution is needed when analyzing the nature of arene-anion interactions, where ETS-NOCV can give unusually large individual components in some cases.

In the report of United Nations at the beginning of 1990s stress was marked as a disease of 20th century, as its role in the development of numerous psychosomatic disorders was undoubtedly confirmed. On these lines, contemporary investigations of psychosomatic diseases imply the necessity of application of holistic methods, oriented to healing the person as a whole and not disease as a symptom of disorder of the whole, suggesting their macroscopic quantum origin. In the focus of these quantum-holistic methods are body's acupuncture system & consciousness - which (within the Feynman propagator version of quantum mechanics) have informational structure of quantum-holographic Hopfield-like associative neural network - with very significant quantum-holographic psychosomatic implications. So, all holistic acupuncture-based & consciousness-based approaches and techniques can be treated as quantum-informational therapies, by imposing new healing boundary conditions in the energy-state space of EM quantum-field-related acupuncture system/(individual and collective) consciousness. The above mentioned quantum-holographic psychosomatic framework provides better understanding of the nature of psychosomatic diseases, which might help in developing strategies for psychosomatic complementary and integrative medicine in the 21st century.

A hundred years ago, physics underwent one of its most dramatic transformations - a paradigm shift that fundamentally changed our understanding of nature. Over the course of several revolutionary months in 1925 and early 1926, quantum mechanics emerged as a new, foundational theory of the microscopic world. With the publication of key papers by Werner Heisenberg and Erwin Schrödinger, the theoretical framework was established that radically redefined our perception of physical reality. These works demonstrated that atoms and subatomic particles do not obey the laws of classical mechanics, but instead follow entirely new, quantum laws. Born in those intense months, quantum mechanics became one of the cornerstones of modern physics and a lasting source of inspiration in both theoretical and applied sciences. This paradigmatic shift opened new avenues of research and laid the groundwork for scientific discoveries that continue to shape our understanding of nature today. This paper is dedicated to those pivotal historical moments - the months in which science made one of its deepest leaps and most consequential strides in comprehending the world.

Small water bodies are particularly vulnerable to environmental disturbances, with fish mass mortality increasingly associated with anthropogenic stressors. This study researches the potential role of potentially toxic elements (PTEs) in the mass fish die-off in December 2012 at the Aleksandrovac Reservoir in Serbia. Muscle, liver, and gills of twenty specimens of silver carp (Hypophthalmichthys molitrix) and common bream (Abramis brama) were analyzed for concentrations of 14 PTEs. Common breams had higher PTE levels due to their bottom-feeding habits and sediment exposure. The liver showed the highest concentrations of potentially toxic elements (PTEs), and elevated Metal Pollution Index (MPI) values in this organ indicate prolonged exposure to environmental contaminants. The concentrations of As, Cd, Pb, Hg, Fe, Cu, and Zn in muscles were below Serbian and EU legislation limits, though some common bream specimens showed slightly elevated Cd and Pb concentrations. While PTEs did not directly cause the die-off, their accumulation poses an ecological risk, emphasizing the need for permanent monitoring.