Vinča Institute of Nuclear Sciences

Today, hydrogel dressings that can protect injury sites and effectively promote healing have become highly desirable in wound management. Therefore, multifunctional silver-poli(N-isopropylacrylamide/itaconic acid) (Ag-P(NiPAAm/IA)) hydrogel nanocomposites were developed for potential application as topical treatment dressings. The radiolytic method, used for the crosslinking of the polymer matrix as well as for the in situ incorporation of silver nanoparticles (AgNPs) into the polymer matrix, enables the preparation of hydrogel nanocomposites without introducing harmful and toxic agents. Moreover, materials produced using γ-irradiation are simultaneously sterilized, thus fulfilling one of the basic requirements regarding their potential biomedical applications. The NiPAAm/IA ratio and the presence of AgNPs influenced the microstructural parameters of the investigated systems. Increasing the IA content leads to the formation of a more porous polymer matrix with larger pores, while the incorporated AgNPs act as additional junction points, decreasing the porosity and pore size of the resulting nanocomposite hydrogels. Swelling studies showed that most investigated systems uptake the fluids from their surroundings by non-Fick diffusion. Further, the Ag+ ion release, antibacterial activity, and cytotoxicity of Ag-P(NiPAAm/IA) hydrogel nanocomposites were examined to evaluate their biomedical potential. All hydrogel nanocomposites showed an initial burst release of Ag+ ions (useful in preventing bacteria adherence and biofilm formation), followed by a slower release of the same (ensuring sterility for longer use). An antibacterial activity test against Escherichia coli and Staphylococcus aureus showed that Ag-P(NiPAAm/IA) hydrogel nanocomposites, with silver concentrations around 10 ± 1 ppm, successfully prevent bacterial growth. Finally, it was shown that the investigated hydrogel nanocomposites do not exhibit a cytotoxic effect on human keratinocyte HaCaT cells. Therefore, these multifunctional hydrogel nanocomposites may promote wound repair and show promising potential for application as functional wound dressing.

In this study, scaffolds based on natural polymer gelatin A, blended with polyvinylpyrrolidone were crosslinked by genipin (0.5 and 1 wt%), in order to investigate their mechanical performance and potential for biomedical application. Semi‐solid extrusion (SSE) 3D printing technique was used, enabling in situ crosslinking of the blend during processing. Swelling test showed that the swelling ratio reduces with higher concentration of genipin due to an increased crosslinking. The FTIR analysis confirmed the crosslinking of scaffolds by genipin. DSC analysis and mechanical testing have shown improved thermal and mechanical properties. Morphological analysis of scaffolds by FESEM showed increased toughening of the material with the crosslinking. Tensile strength and microhardness showed a significant rise in scaffolds with the increase in genipin content, which was up to 93.8% and 125.3%, respectively. These findings were in accordance with morphological features present in samples. The biological effect of the scaffold matrix system was evaluated by qualitative and quantitative cytotoxicity assessment in vitro, demonstrating the absence of cytotoxicity in tested preparations in a direct test. The cytotoxicity index based on the metabolic activity of cells in an indirect test showed up to 20% reduction of viability compared with the control, confirming the absence of cytotoxicity, which was additionally verified by propidium iodine staining of the cells exposed to scaffolds. The presented gelatin‐based crosslinked scaffolds obtained by 3D printing represent good candidates for biomedical application and future research that includes further in vitro and in vivo analysis.

Environmental radiation monitoring involves measuring the level of radioactive contamination of the air, including the relevant meteorological measurements at the micro-location type of measurements, which are essential for evaluating the extent of environmental factors and effectively managing the exposure of the population and the impact on the environment. These measurements are crucial in ensuring a comprehensive understanding of the ecological conditions and facilitating informed decision-making to safeguard the well-being of communities and ecosystems. This paper shows the relation between the change of ambient dose equivalent H*(10) rate in the air and precipitation due to washing out and rainout in the atmosphere. Measurements were made in the vicinity of nuclear facilities within the public company Nuclear Facilities of Serbia at the weather station mounting pole 114 m above sea level. To illustrate the relationship between the measured ambient dose equivalent H*(10) rate and precipitation levels, a variation of these values was employed specifically during the most rain-laden months in 2019 and 2020. Besides, an interlaboratory comparison was conducted to ascertain the system's operational validation. A thorough examination of this ratio distinctly reveals the impact of heavy rainfall on the ambient dose equivalent H*(10) rate, thereby rationalizing the observed elevated values. Importantly, these heightened readings were not attributed to any inadvertent release of radioactive effluents from nuclear facility operations in this particular instance.

This paper introduces a measuring system designed to determine the air density correction factor for ionization chambers open to the atmosphere. The system is intended for use in clinical and radiotherapy facilities, secondary standard dosimetry laboratories, and other settings where open-to-the-air ionization chambers are commonly utilized. While there are numerous universal and laboratory-grade instruments available for measuring relative humidity, air pressure, and ambient temperature, integrated systems that can measure these parameters and calculate and display the air density correction factor are rare, particularly in the domestic market in Serbia. This paper details the developed hardware, including specifications for the sensors used, as well as the software developed for microcontrollers and personal computers. Measurement results and simplified measurement uncertainty budgets are also presented and discussed.

To understand excellent emission and sensitivity for hydrostatic pressure luminescent ions host material, the first principles calculations carried out within density functional theory (DFT) framework are performed to clarify the electronic structure of neat and doped with Ni²⁺ ions KMgF3 single crystals. The results of band structure calculations show that F2p states are the principal contributors to the KMgF3 valence band, mainly in its upper and central parts, while in the energy band gap of the KMgF3:Ni²⁺ phosphor, new electronic states associated with the Ni²⁺ 3d‐orbitals are formed. Furthermore, the zero phonon line (ZPL) spin‐forbidden transition emission energies, (³A2⇄¹E) ZPL, (³A2⇄³T2) ZPL, strength of the octahedral crystal field, 10Dq (³A2→³T2)ZPL, are calculated for the KMgF3:Ni²⁺ phosphor. Any changes of the Em(³A2⇄¹E)ZPL transition energy of the KMgF3:Ni²⁺ phosphor with pressure increasing from 0 to 20 GPa are not detected, while the crystal‐field strength increases linearly with increasing pressure. Present results bring a foresight tool for predicting physicochemical properties of undoped and doped wide‐gap fluorides; KMgF3:Ni²⁺, without any toxic/harmful or expensive rare‐earth can be effectively used as an optical manometer in 0–20 GPa, which covers the almost whole pressure range available at present in Diamond anvil cell experiments.

Antitumor effect of new Pd( ii ) complexes having pyridine derivatives of 2.6-dicarboxamide as chelating ligand was assessed by examination of nucleophilic substitution reactions, DNA/HSA interaction, molecular docking and cytotoxic activity.

Simple Summary Rectal cancer (RC) is the third most common gastrointestinal malignancy, with a rising incidence, particularly among the population under 50 years old. Extramural venous invasion (EMVI) is defined as the presence of malignant cells in veins beyond the muscularis propria near the primary colorectal tumor. The aim of our retrospective study was to assess the prognostic value of separate pathological EMVI reporting in operative RC samples and to determine its relationship with standard pathohistological and surgical parameters among a selected cohort of RC patients from our institution. Finally, EMVI is proved not only to be a feature of aggressive tumor behavior, but also as a separate and independent parameter in patients with rectal cancer. The results we obtained strongly suggest the importance of separately reporting extramural vascular invasion (EMVI) from lymphovascular invasion (LVI) in daily practice, as well as that EMVI could be a good addition to TNM staging. Abstract Background/Objectives: Vascular invasion, especially extramural vascular invasion (EMVI), has emerged as a prognostic parameter for rectal cancer (RC) in recent years. Prediction of recurrence and metastasis development poses a significant challenge for oncologists, who need markers for prediction of adverse outcome. The aim of this study was to examine the prognostic significance of pathohistologically detected EMVI in untreated rectal cancer and its implications in separate reporting. Methods: We examined 100 untreated RC patients who underwent curative resection from January 2016 to June 2018 with a follow-up of 5 years. Patients were divided into equal EMVI− and EMVI+ groups based on histological re-examination of H&E-stained postoperative surgical samples. Results: The presence of EMVI within the selected cohort was significantly associated with female gender, T3/T4 and N1/N2 post-operative stages, positive lymph nodes, lymph node ratio LNR2 and LNR3 groups, abundant tumor-infiltrating lymphocytes, positive lympho-vascular invasion (LVI), perineural (PNI), and circumferential resection margin (CRM) (p < 0.05 in all tests). Within EMVI+ patients, local recurrences and/or metastases and death outcomes were more frequent events (p = 0.029 and p = 0.035, respectively), while survival analyses revealed that EMVI+ patients had significantly shorter overall survival (OS, p = 0.040) and disease-free survival (DFS, p = 0.028). Concerning LVI, differences in OS between LVI+ and LVI− patients were not statistically significant (p = 0.068), while LVI+ patients had significantly shorter DFS (p = 0.024). Moreover, univariate COX regression analysis demonstrated the negative impact of EMVI on OS (HR: 2.053, 95% CI: 1.015–4.152; p = 0.045) and DFS (HR: 2.106, 95% CI: 1.066–4.870; p = 0.038), which was not the case for LVI + RC patients. Conclusions: The obtained results strongly suggest the significance of separate reporting of EMVI from lympho-vascular invasion, as it is potentially a surrogate marker for adverse prognosis and outcome.

Nanostructured iron (III) oxide was prepared by a facile hydrothermal method using poly(triazine imide) (PTI) as a sacrificial template. The physicochemical properties of pristine iron oxide and its analogue obtained in the presence of PTI confirmed strong effect of the latter as the morphology improving agent. Moreover, application of nitrogen rich semiconducting polymer during hydrothermal synthesis increased number of defects. The obtained sample was used as an electroactive additive for carbon‐paste electrode. PTI‐modified sample demonstrated 1.52 times higher oxidation current, and 1.39 lower charge transfer resistance compared to hematite obtained without PTI, as was confirmed by CV and EIS data. Therefore, it was proposed to use the as a sensor for the detection of gallic acid. The developed method showed excellent linearity within a concentration range of 67 nM to 17.7 µM with a detection limit equal to 44 nM and limit of quantification of 132 nM. Stablitity and reproducibility tests, as well as real sample analysis confirmed applicability of the proposed sensor for practical application. Excellent electrochemical properties of the submicron hematite particles are attributed to the developed lattice defects, which served as reaction centers and charge transducing points.

In this study we introduce photoluminescence analysis of nano powder YAlO3 doped with Er³⁺ and Yb³⁺. We compare this material with other hosts, Gd2O3, CaGdAlO4 and Y2O2S, doped with Er³⁺ and Yb³⁺. Beside usual ways to characterize these materials we also include visual comparison by data dimensionality reduction techniques, as a way for initial assessment of a new material. Samples were excited at 980 nm by using pulsed laser diode to analyze effects of host matrices on optical emission of erbium. For this purpose the luminescence spectra of all samples were obtained in a continuous series of measurements under the same experimental conditions. Moreover, the samples were prepared in the same way, by combustion synthesis. We compare the possibilities of using these materials for remote temperature sensing, showing that YAlO3:Er³⁺, Yb³⁺ is a good candidate for remote temperature sensing.

Current industrial herbicides have a negative impact on the environment and have widespread resistance, so computational studies on their properties, elimination, and overcoming resistance can be helpful. On the other hand, developing new herbicides, especially bioherbicides, is slow and costly. Therefore, computational studies that guide the design and search for new herbicides that exist in various plant sources, can alleviate the pain associated with the many obstacles. This review summarizes for the first time the most recent studies on both aspects of herbicides over 10 years.

Although low-cost air quality sensors facilitate the implementation of denser air quality monitoring networks, enabling a more realistic assessment of individual exposure to airborne pollutants, their sensitivity to multifaceted field conditions is often overlooked in laboratory testing. This gap was addressed by introducing an in-field calibration and validation of three PAQMON 1.0 mobile sensing low-cost platforms developed at the Mining and Metallurgy Institute in Bor, Republic of Serbia. A configuration tailored for monitoring PM2.5 and PM10 mass concentrations along with meteorological parameters was employed for outdoor measurement campaigns in Bor, spanning heating (HS) and non-heating (NHS) seasons. A statistically significant positive linear correlation between raw PM2.5 and PM10 measurements during both campaigns (R > 0.90, p ≤ 0.001) was observed. Measurements obtained from the uncalibrated NOVA SDS011 sensors integrated into the PAQMON 1.0 platforms exhibited a substantial and statistically significant correlation with the GRIMM EDM180 monitor (R > 0.60, p ≤ 0.001). The calibration models based on linear and Random Forest (RF) regression were compared. RF models provided more accurate descriptions of air quality, with average adjR² values for air quality variables in the range of 0.70 to 0.80 and average NRMSE values between 0.35 and 0.77. RF-calibrated PAQMON 1.0 platforms displayed divergent levels of accuracy across different pollutant concentration ranges, achieving a data quality objective of 50% during both measurement campaigns. For PM2.5, uncertainty (Ur${U}_{\text{r}}$) was below 50% for concentrations between 9.06 and 34.99 μg/m³ in HS and 5.75 and 17.58 μg/m³ in NHS, while for PM10, it stayed below 50% from 19.11 to 51.13 μg/m³ in HS and 11.72 to 38.86 μg/m³ in NHS.

A new model of a spin-1/2 quantum kicked rotor coupled with a highly inhomogeneous magnetic field is proposed. The model is mapped into the appropriate tight-binding equations, and then the problem of localization is considered. The introduced tight-binding model is verified by calculating the localization length for the appropriate quasi-energy states. In particular, it is shown that the functional form of the spin-dependent term in kicking potential is exclusively responsible for the growth of the localization length with an increase in the magnitude of the magnetic field. The growth is more pronounced if the inhomogeneity of the magnetic field is greater. Thus, quasi-extended states appear as a consequence of strongly conspicuous inhomogeneity, and they exhibit nonstandard localization properties. Their existence is also shown by calculating the appropriate inverse participation ratio and pair-correlations. Therefore, some kind of "localization–delocalization" transition is possible here. This has been demonstrated as well by following the time evolution of the wave packet in the angular momentum space, assuming increasing inhomogeneity. For extremely large inhomogeneity, dynamical localization is destroyed. The model proposed here can serve as an assessment simulator for the induced electric dipole moment in a hydrogen-like atom, assuming the existence of anisotropy.

Tantalum carbide (TaC) is an extremely hard, brittle, refractory ceramic material with excellent physical properties, which makes it a desirable material in e.g. aerospace industries. In order to explore the range of feasible modifications of TaC, we have executed a crystal structure prediction study of the TaC chemical system using a multi‐methodological approach, via enthalpy landscape explorations of pristine TaC at different pressures, supplemented by data mining searches in the ICSD database. Local structure relaxations have been accomplished by using Density Functional Theory (DFT). The global minimum is found to correspond to the equilibrium rock salt (NaCl) type modification. Additionally, eight new phases of tantalum carbide are predicted to be feasible: the WC‐type, the NiAs‐type, the 5‐5‐type, the ZnS‐type, the Ring_TaC‐type, the CsCl‐type, the Ortho_TaC‐type, and the Tetra_TaC‐type. Furthermore, the elastic and mechanical properties of the predicted TaC modifications were explored on the DFT level of computation. The promising values of some of the mechanical properties of the proposed tantalum carbide modifications suggest that various scientific, industrial and technological applications of TaC should be possible.

The treatment of patients with metastatic colorectal cancer (mCRC) is complex and is impacted by the location of the primary tumor (LPT). Our study aims to emphasize the importance of LPT as a prognostic and predictive marker as well as to examine the significance of HER2 overexpression in patients with mCRC, particularly in relation to the response to Epidermal Growth Factor Receptor Antibody treatment (anti-EGFR therapy). In this study, 181 patients with Kirsten RAS (KRAS) wild-type mCRC who received anti-EGFR therapy were included. Among them, 101 had left colon cancer (LCC) and 80 had right colon cancer (RCC). Results demonstrated that patients with KRAS wild-type LCC had better median overall survival (OS) (43 vs. 33 months, p = 0.005) and progression-free survival (PFS) (6 vs. 3 months, p < 0.001) compared to those with RCC. Multivariate analysis identified mucinous adenocarcinoma (p < 0.001), RCC location (p = 0.022), perineural invasion (p = 0.034), and tumors at the resection margin (p = 0.001) as independent predictors of OS, while mucinous adenocarcinoma (p = 0.001) and RCC location (p = 0.004) independently correlated with significantly shorter PFS. In addition, human epidermal growth factor receptor 2 (HER2) positive expression was significantly associated with worse PFS compared to HER2 negative results (p < 0.001). In conclusion, LPT is an important marker for predicting outcomes in the treatment of wild-type mCRC using anti-EGFR therapy, since patients with RCC have a statistically significantly shorter PFS and OS. Further investigation is needed to understand the role of HER2 overexpression in wild-type mCRC, as these patients also exhibit shorter survival.

The explanation of the n-type silicon thermoelastic photoacoustic response is given by electro-acoustic analogies, which clarify the influence of excess free carriers as heat carriers. It was found that electro-acoustic analogies could interconnect different theoretical models of heat flow and carrier dynamics aiming to find the optimal experimental conditions for the efficient free carrier influence analysis of the sample thermoelastic photoacoustic response. Theoretical analysis was based on the comparison between the composite piston, surface recombination, and RC filter frequency response models, extrapolating the behavior of the photoacoustic esponse much beyond the experimental frequency domain. Experimental analysis was based on the open-cell photoacoustic setup operating under the transmission configuration within the modulation frequencies range from 20 Hz to 20 kHz. The accuracy of our predictions and the validity of electro-acoustic analogies are confirmed by measuring 875 μm plasma-thick and 35 μm plasma-thin silicon samples.

This study investigates the impact of changing parameters on the photocatalytic degradation of carbofuran (CBF) using laser-treated TiO2 nanotube arrays on a Ti mesh under simulated sunlight irradiation and assessing toxicity during photocatalytic degradation. Various parameters, including the stirring effect, light intensity, initial CBF concentration, and variation in the active surface area of laser-treated TiO2 photocatalysts, were examined to determine their impact on degradation efficiency. The photodegradation kinetics were monitored using ultra-performance liquid chromatography with a PDA detector (UPLC-PDA) and UV-Vis spectrophotometry, while mineralization was assessed by a total organic carbon (TOC) analyzer. The photocatalytic degradation of CBF is enhanced by an increase in the active surface area of the TiO2 photocatalyst, light intensity, and the introduction of stirring, but it decreases with an increase in the initial concentration of CBF. The toxicity assessments revealed that the cytotoxicity of CBF initially increased during the degradation process but decreased after further treatment, indicating the formation and subsequent breakdown of toxic intermediates. The phytotoxicity test showed that longer degradation times resulted in higher toxicity to plant growth. This study provides new insights into the photocatalytic degradation of CBF with TiO2, the importance of parameter optimization for more efficient treatment, and the use of toxicity tests to confirm the success of the photocatalytic process.