Institute of Technical Sciences of SASA

The development of selective anticancer agents remains a central objective in medicinal chemistry. Here, we report the synthesis, structural characterization, and biological evaluation of the first metal complex of a quinoline-based thiazolyl-hydrazone ligand [(E)-2-(8-(quinolin-2-ylmethylene)hydrazinyl)-4-(4-tolyl)-1,3-thiazole)] (HL). Obtained octahedral Zn(II) complex [Zn(HL)2](NO3)2, (1), is based on two NNN tridentate coordinated ligands. In vitro cytotoxicity assays revealed that the complex exhibits potent and selective activity against lung adenocarcinoma A-549 and colorectal carcinoma HCT-116, while sparing non-tumorigenic human embryonic kidney HEK-293 cells. Mechanistic studies demonstrated that the complex induces S-phase arrest, inhibits DNA synthesis, and triggers significant DNA damage as indicated by increased p-γH2AX expression. These effects were accompanied by mitochondrial depolarization, caspase-3/7 activation, and phosphatidylserine externalization, confirming apoptosis via the intrinsic pathway. The compound further inhibited tumor growth in 3D spheroids and the chick chorioallantoic membrane model without overt toxicity. Compared to the free ligand and reference chemotherapeutics, the zinc complex showed improved efficacy and selectivity. These results highlight the potential of metal coordination to enhance the biological activity of hybrid ligands, supporting further development of this class of compounds as selective anticancer agents.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-27051-4.

Cardiovascular diseases (CVDs) are the leading cause of death globally, often complicated by thromboembolic events. Plasmin, a key enzyme in fibrinolysis, is crucial for managing these conditions. Elevated or reduced plasmin levels can indicate thrombotic risks, making it a valuable diagnostic marker. Recent biotechnological advances have developed diagnostic kits to measure plasmin activity, aiding early detection and intervention. Fungal proteases, particularly from micromycetes, are emerging as promising agents in anticoagulant therapy. This study investigates three Aspergillus species - A. caespitosus, A. jensenii and A.neotritici - for their potential to produce novel biomedical components. The fungi were cultured, and their proteolytic profiles were analyzed. Key findings include the identification of specific proteases with plasmin-like and protein C-activating activities. These enzymes were purified using isoelectric focusing and characterized through SDSPAGE and zymography. The study confirmed that A. jensenii, and A. neotritici produce proteases with plasminlike activity, with A. neotritici showing a single 35 kDa non-specific protease, and A. jensenii exhibiting two proteases (33 kDa and 100 kDa) in the acidic zone and one (110 kDa) in the neutral zone, the latter exhibiting specific chymotrypsin and plasmin-like activity. Among the studied strains, A. neotritici exhibited the fastest secretion of proteases with plasmin-like activity, making it a promising source of enzymes with potential clinical applications. In contrast, A. caespitosus and A. jensenii displayed more complex protease compositions, featuring multiple active enzymes. Notably, one of the A. jensenii proteases showed pronounced specificity toward chymotrypsin and fibrinolytic substrates, indicating its suitability for the development of targeted therapeutic agents. These findings suggest the potential of these fungal proteases for developing novel anticoagulant therapies and diagnostic tools.

The anodic oxidation of titanium implants is a practical, cost-effective method to enhance implant success, especially due to rising hypersensitivity concerns. This study investigated the electrochemical behavior, surface characteristics, and biocompatibility of anodized commercially pure titanium (cpTi, grade IV). Anodization is performed on polished, cleaned cpTi sheet samples in 1 M H2SO4 using a constant voltage of 15 V for 15 and 45 min. The color of the oxide layer is evaluated using the CIELab color space, while composition is analyzed by a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS). Additionally, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) are performed to identify and monitor the phase transformations of the formed titanium oxides. Corrosion measurements are performed in 9 g L−1 NaCl, pH = 7.4, and show the excellent corrosion stability of the anodized samples in comparison with pure titanium. The biological response is assessed by determining mitochondrial activity and gene expression in human fibroblasts. Anodized surfaces, particularly Ti-45, promote higher mitochondrial activity and the upregulation of adhesion-related genes (N-cadherin and Vimentin) in human gingival fibroblasts, indicating improved biocompatibility and the potential for enhanced early soft tissue integration.

This study investigates the relationship between employee satisfaction with workplace care and their performance, focusing on three critical dimensions: management’s commitment to employee safety and health, the quality and accessibility of protective equipment, and the provision of medical allowances. The research was conducted in food industry in Serbia during 2021, involving 1123 participants. A cross-sectional design was chosen to meet the study’s purposes. The research findings indicate that medical allowances are the most critical aspect of employee satisfaction, which can be justified by the region’s low standard of living. The study also reveals significant discrepancies in satisfaction levels between management and employees regarding Human Resource Management and Occupational Health and Safety policies and practices, emphasizing the need to consider data selection bias present in such research. Additionally, the results demonstrate that individual characteristics and employees’ experiences related to Occupational Health and Safety influence their satisfaction with Human Resource Management and Occupational Health and Safety. The findings are significant in the context of ongoing reforms in social and pension insurance in the Republic of Serbia and negotiations between labor unions and the Ministry of Labor. They also contribute to a theoretical discourse in the context of the Social Exchange Theory, which conceptualizes Human Resource Management and Occupational Health and Safety policies and practices as gestures of goodwill by employers, that elicit positive responses from employees.

Comparative analysis of red mud reduction techniques was performed using both carbothermal and hydrogen-based reduction methods, combining thermochemical modeling and experimental validation. The reduction process is mostly important because of the high contamination risk assessment of soil with disposed red mud. Therefore, the minimization of red mud during the reduction process can be a novel strategy for the production of metallic iron and solid residue for hydrometallurgical treatment. Different strategies of hydrogen and carbon reduction in static and dynamic conditions were studied between 700 °C and 1700 °C. The separation of solid residue and formed iron was analyzed using magnetic separation. The main aim was to study the advantages and disadvantages of using decarbonizing technologies for the treatment of red mud, aiming to develop an environmentally friendly process. Thermochemical analysis of the reduction offered new data about mass losses during our process through the evaporation, thermal decomposition, and formation of metallic carbide.

A heat loss flowmeter for water was made of two negative temperature coefficient (NTC) thick film thermistors Th1 and Th2 and placed in a metal housing. The first thermistor Th1 is cold and measures input water temperature <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T} _{\text {w}}$ </tex-math></inline-formula>, and the second thermistor Th2 is self-heated at a constant voltage and measures water flow rate Q. At first temperature responses T(Q), heat loss and time delay <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${t} _{\text {d}}$ </tex-math></inline-formula> were measured and analyzed; then a temperature hysteresis loops of self-heating thermistor at switching waterflow regime was measured. The electrical responses I(Q) were measured using the flowmeter and digital acquisition card (DAC). An independent ultrasonic flowmeter was used in series with a novel heat loss flowmeter. The current values of temperature T(Q, t) of the water flow Q(t) were obtained using Steinhart-Hart equation for thermistors. Input water temperature <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T}_{\text {w}}$ </tex-math></inline-formula> was used as a parameter (in the range of 5 °C–25 °C). The maximum thermistor power dissipation was less than 1 W. The inaccuracy of the water flow rate measurement was estimated to be less than 3%. The measuring flowmeter range of 0.003–0.3 L/s (1/2 in pipe) is suitable for measuring water consumption in households.

A powder of \mathrm{BaFe_{12}}\mathrm{O_{19}} composition (barium hexaferrite) was prepared by using the respective mixture of metal oxides and performing a solid-state reaction at 1000?C/4h in air. The obtained barium hexaferrite powder was milled for a prolonged time in the planetary ball mill and agate mill to achieve submicron powder. The \mathrm{BaFe_{12}}\mathrm{O_{19}} submicron powder was mixed with \mathrm{TiO_2} nanopowder as a dopant. The prepared powder mixture was characterized by using XRD and SEM techniques. After that, the barium hexaferrite powder mixture was pressed into thin and small diameter size disk-shaped samples and sintered at different sintering profiles from 1050?C to 1275?C/2h to 6h. The sintered samples were also characterized by using XRD and SEM. The main electrical properties such as capacitance (intergranular) and bulk resistance R at 1 Hz to 100 Hz were measured at room temperature. The dielectric permittivity was calculated from the equivalent scheme of disk capacitor. The obtained results were used for observing space charge relaxation effects and development of multilayer capacitor forenergy storage device.

This paper presents a new class of erasure-correcting codes (ECCs) aimed at enhancing cryptographic security of certain encryption schemes. The proposed ECCs employ integer arithmetic to encode and decode data bits and can correct all data bytes, each affected by exactly two erasures.. In the enhanced encryption scheme, the ciphertext produced by the initial encryption undergoes further processing. The enhancement leverages specific fragmentation, the proposed ECCs and a simulated noisy channel. For legitimate users, the simulated noisy channel functions as a binary erasure channel, while for an attacker without the secret key, it acts as a channel with random deletions. Security notation and evaluation follow the traditional approach, assessing the attacker’s advantage in distinguishing between two ciphertexts versus random guessing. This evaluation employs dedicated analysis based on information-theoretic findings on the capacity of certain deletion channels and is supported by illustrative numerical examples.

. 94 maximum settling time of 50 % of the foam column was observed up to an air flow rate of 150 ml/min.The optimum treatment time of the foaming solution was 10 min at an air flow rate of 150 ml/min.It is concluded that at the volume of the foaming agent from 30 to 60 ml the obtained values of the settling time of 50 % of the foam column fall within the range of values given in GOST R 50588-93.