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Magdalena Stevanović1, Branimir Kovačević2, Jana Petković3, Metka Filipič3, Dragan Uskoković11Institute of Technical Sciences of Serbian Academy of Sciences and Arts, 2Institute of General and Physical Chemistry, Belgrade, Serbia; 3Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Ljubljana, SloveniaAbstract: Highly stable dispersions of nanosized silver particles were synthesized using a straightforward, cost-effective, and ecofriendly method. Nontoxic glucose was utilized as a reducing agent and poly- α, γ, L-glutamic acid (PGA), a naturally occurring anionic polymer, was used as a capping agent to protect the silver nanoparticles from agglomeration and render them biocompatible. Use of ammonia during synthesis was avoided. Our study clearly demonstrates how the concentration of the capping agent plays a major role in determining the dimensions, morphology, and stability, as well as toxicity of a silver colloidal solution. Hence, proper optimization is necessary to develop silver colloids of narrow size distribution. The samples were characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and zeta potential measurement. MTT assay results indicated good biocompatibility of the PGA-capped silver nanoparticles. Formation of intracellular reactive oxygen species was measured spectrophotometrically using 2,7-dichlorofluorescein diacetate as a fluorescent probe, and it was shown that the PGA-capped silver nanoparticles did not induce intracellular formation of reactive oxygen species.Keywords: silver nanoparticles, poly-α, γ, L-glutamic, green synthesis, morphology, cytotoxicity

By implementing the standardization of logistics services, modern organizations strive to reduce the cost of circulating inefficient services and improve overall efficiency, thereby aiding overall economic growth. The aim of this paper is to show how logistics standardization affects the development of corporate market competitiveness. First, the standardization of logistics services significantly promotes the corporate tendency to establish a long-term market position. Also, the standardization of logistics functions aims to mitigate financial fluctuations and accelerate organizational growth. And finally, the understanding of the globalization of business relations in the context of business logistics should show how traditional logistics functions have shifted towards modern trends. This paper also presents the role of logistics standardization in promoting corporate mechanisms in the context of restructuring operations aimed at increasing the adaptive capacity of the organization and its further distribution of services in different markets.

Breaking news are usually disturbing. Natural disasters, wars, epidemics, etc., are reported as breaking news. This paper reports a decreased danger of spreading of epidemics caused by the JN.1 variant, since analyses indicate that infectivity of the new variant is decreased compared to most earlier variants, which is confirmed by the number of cases (7500 daily in USA). Moreover, JN.1, despite the great number of mutations, has not been able to achieve the values of Gibbs energy change of biosynthesis (and thus virus multiplication rate) of the Hu-1 wild type. The research shows that infectivity and pathogenicity of the JN.1 variant has not reached worrying size, which means that there is no reason to expect the epidemiologic situation getting worse.

Introduction/Objective. Previous investigations pointed to a notable frequency of periodontitis appearance in persons with mental disorders, but almost none of them were addressed to the periodontitis among young adults with mental disorders as a target group, which can have high public health significance. Therefore, the aim of this investigation was to estimate the prevalence of periodontitis among young adults suffering mental disorders and to determine probable risk factors for their overall periodontal health. Methods. The investigation included two groups of patients, each group having 81 participants-the study group (young adults with mental disorders) and the control group (mentally healthy young adults). The study instruments included a questionnaire (age, gender, psychoactive substances use, and maintaining oral hygiene) and community periodontal index for both groups, and the data concerning primary disease of mentally deceased patients (diagnostic category, mental disorder duration, number of hospitalizations, and psychotropic medications). Results. In terms of psychoactive substances use and maintaining oral hygiene, statistically significant differences were observed between groups in all independent variables. Young adults with mental disorders shown a high prevalence of periodontitis compared to the mentally healthy young adults. Also, gender, smoking habits, and the use of antipsychotics exhibited as possible risk factors contributing current periodontal health of young mentally deceased patients. Conclusion. This study indicates the need for more consideration for periodontal health among people with mental disorders and determination of potential models for its improvement.

act Considering the increase in traffic accidents in Serbia the new measures to increase traffic safety are required. This research examines different age-gender categories of drivers involved in traffic incidents between 2016 and 2021. Findings revealed that the majority of traffic accidents in the research period occurred in the afternoon hours. The identification of the primary risk factors indicated as the cause of traffic accidents received special emphasis. Thus, among the groups of factors, taking reckless actions by the drivers and incorrect execution of traffic actions by the driver are leading, especially for the youngest and oldest categories of drivers. Driving under the influence of alcohol is the most significant individual risk factor for all gender-age categories of drivers, particularly for the youngest drivers. The findings can be used as guidelines for developing targeted policies aiming at reduce the frequency of traffic accidents and raise the degree of protection for road users.

Since the first national strategy (2009) aimed at eliminating discrimination against women in all areas in the domain of public institutions, including education, publishing houses which publish school textbooks have started to implement gendersensitive language into their materials. Today, more than ten years later, gender-sensitive language practice has already been introduced into many textbooks for elementary and secondary schools. However, it still has not been approved by the Board for Standardization of the Serbian Language. This paper presents examples of the use of gender-sensitive language collected from 13 elementary school textbooks published in the period 2019-2022 and appproved by the Ministry of Education, Science and Technological Development. Based on those examples, which largely implemented the first proposals for the use of gender-sensitive language formulated by Svenka Savić (Savić et al, 2010), it is possible to create new recommendations for a more consistent use of language that would correspond to the requirements of legal regulations in the field of gender equality as well as to the language norm.

Introduction/Objective. Bone resorption is a common problem in dentistry, and bone reparation cannot be easily achieved. Several techniques of bone grafting and the use of low-level laser treatment (LLLT) as a new therapeutic optional recommended for improving bone repair were applied. The aim of the study was to investigate the influence of LLLT in bone repair of artificially made bone defects in the rat mandible using histomorphometry. Methods. The research was carried out on 60 female rats. Bone defects were made in the mandible, and animals were divided into two groups, each containing 30 animals. In the study group, the implantation site was submitted to GaAlAs laser irradiation 670 nm, 5 mW, 4 minutes per day for 5 days. The control group had no postoperative treatment. The animals were sacrificed after two, six, and eight weeks post LLLT, and preparations were analysed by histomorphometry, determining bone area fraction, bone area, integral density, mean density, and density variation. Results. Histomorphometric analysis revealed statistically higher values of area fraction, area, and integral density in the study group after two and six weeks. However, no beneficial laser effect was noticed after eight weeks. Conclusion. Low-level lasers have a stimulating effect on reparatory mechanisms in the early regeneration stage of artificially made bone defects in the rat mandible and can be used as a useful helping method in bone treatment.

Introduction. A dentigerous cyst is a pathological lesion associated with the crown of the unerupted or impacted tooth. Decompression is proposed as the initial treatment for large cysts, especially in younger patients. The aim of this study was to present clinical, radiological, histopathological, and therapeutical aspects of the large dentigerous cyst in the maxilla. Case report. A 12-year-old boy with a large dentigerous cyst in the maxilla was referred to our clinic. A dentigerous cyst was associated with the crown of the unerupted maxillary left canine. Management of the cyst included initial decompression with biopsy, followed by secondary enucleation after 9 months and orthodontic treatment. Histopathological examination confirmed the definitive diagnosis of the dentigerous cyst. Conclusion. Initial decompression with a subsequent enucleation proved to be an effective treatment of choice for the large dentigerous cyst.

Background/Aim. A lingual foramen (LF) is a small opening on the lingual surface of the mandible, most frequently located in the middle of the anterior part of the mandible, and shows significant variations in its location, size, and number. The aim of this study was to assess the location and anatomical characteristics of LF using cone beam computed tomography (CBCT). Methods. The research was designed as a retrospective study in which 99 CBCT scans were analyzed. The analysis covered the number of LF, their location concerning the teeth and the mandibular region itself, diameter, distance from the alveolar ridge crest, distance from the inferior border of the mandible, distance from the tooth apex, and position in relation to the tooth apex. Results. The average frequency of LF per patient was 2.4 ± 1.2. The largest number of LF were localized in the region of lower central incisors. Out of the total number of LF, 82.5% belonged to median LF, while 17.5% belonged to lateral LF. In 63.2% of cases, LF had a diameter of ≤ 1 mm, whereas, in 98.3% of cases, it was localized below the tooth apex. There was a statistically significant difference in the distance of LF from the alveolar ridge crest and the LF diameter in relation to gender (p = 0.019; p = 0.008). Conclusion. LF can be reliably localized and visualized using CBCT. It is recommended that CBCT scanning of the mandible be used while planning an oral surgical procedure and implant placement in order to prevent injuries of the neurovascular bundle, which passes through LF.

Sclerotinia stem and root rot, caused by Sclerotinia sclerotiorum, is considered to be an important soil-borne disease of over 400 plant species, including a wide range of species important for agriculture. In vitro and in vivo sensitivity of S. sclerotiorum to several commercial fungicides and biofungicides was studied. The highest efficacy was achieved by boscalid (98%) and fluopyram (80%), and the lowest by a B. subtilis-based product (5%). The isolate was sensitive to all tested products in vitro. Considering the tested synthetic fungicides, fluopyram exhibited the highest toxicity (EC50=0.003 mg/l), while captan exhibited the lowest (EC50=8.94mg/l). Even lower efficacy was achieved by tea tree oil and B. subtilis-based products. The environmental impact of pesticides and biopesticides used for Sclerotinia control was assessed. Modeling of predicted environmental concentrations in soil (PECsoil), coupled with literature toxicity data, served for assessment of pesticides soil risks. A high long-term risk for earthworms was revealed for captan and thiophanate-methyl. Based on both efficacy and risk assessment results, fluopyram was found to have the best properties of all tested conventional pesticides, while tea tree oil exerted better performance than the Bacillus product. Further investigation of combined use of conventional and biopesticides might reveal new perspectives regarding effective Sclerotinia control, while simultaneously reducing negative environmental impact.

The COVID-19 pandemic exposed many issues about the adequacy of the reactions of the states to this infection. Matters of timely reactions, the confusion caused by communications of the national public health institutions, insufficient testing and monitoring capabilities, not enough masks and protective equipment, the capacity of hospitals indicates inadequate national preparedness in many states. In the initial phase, the key policies were determined by the expert public health bodies, with no democratic legitimacy. All such omissions are attributable to states. In this article, we examine if they have the potential to provide the ground for their international liability for the reactions in the pandemic.

Modern trends operating from the environment require a different shaping of the organizational structure of the company. Accordingly, instead of traditional forms, more flexible organizational structures appear that are based on the characteristics of organic design. The emphasis is primarily on accepting change, decentralization of decision-making, a wider range of control, teamwork, adequate organizational culture, good interpersonal relationships, continuous learning and innovation development. Technological progress, scientific achievements, and thus the even greater need for continuous learning and acquiring new knowledge, as important characteristics of the modern business environment, have had the greatest impact on shaping the organizational structure of the company. The fact that information technology and knowledge are the basis of new organizational forms speaks in favor of that. Globalization has also played a role in creating the conditions for changing the organizational structure of companies, as well as the time of the COVID 19 pandemic. Organisations have been forced to do business differently and business processes have had to change rapidly in order for organisations to survive. The aim of this work is to indicate the fundamental trends that operate from the business environment and condition the need for the application of more flexible organizational forms. In addition, the aim of the paper is to point out the characteristics of organizational models that have emerged under the influence of these trends.

A multidisciplinary approach based on experiments and mathematical modeling was used in biomimetic system development for three-dimensional (3D) cultures of cancer cells. Specifically, two cancer cell lines, human embryonic teratocarcinoma NT2/D1 and rat glioma C6, were immobilized in alginate microbeads and microfibers, respectively, and cultured under static and flow conditions in perfusion bioreactors. At the same time, chemical engineering methods were applied to explain the obtained results. The superficial medium velocity of 80 μm s-1 induced lower viability of NT2/D1 cells in superficial microbead zones, implying adverse effects of fluid shear stresses estimated as ∼67 mPa. On the contrary, similar velocity (100 μm s-1) enhanced the proliferation of C6 glioma cells within microfibers compared to static controls. An additional study of silver release from nanocomposite Ag/honey/alginate microfibers under perfusion indicated that the medium partially flows through the hydrogel (interstitial velocity of ∼10 nm s-1). Thus, a diffusion-advection-reaction model described the mass transport to immobilized cells within microfibers. Substances with diffusion coefficients of ∼10-9-10-11 m2 s-1 are sufficiently supplied by diffusion only, while those with significantly lower diffusivities (∼10-19 m2 s-1) require additional convective transport. The present study demonstrates the selection and contribution of chemical engineering methods in tumor model system development.

Organic-inorganic perovskites have attracted much attention from researchers due to their high absorption in the visible part of the spectrum and low-cost fabrication. After absorption of the light, electron-hole pairs are formed. To separate electron-hole pairs and reduce recombination, perovskite is combined with TiO2 which has as a consequence, a spontaneous transition of electrons from perovskite to TiO2. This research aims to increase the contact surface of perovskite and TiO2 nanotubes by filling the nanotubes with perovskite material. The solution of methylammonium lead bromide perovskite (CH3NH3PbBr3) in dimethylformamide (DMF) was deposited on anodically synthesized TiO2 nanotubes by the high vacuum system and inert gas. The procedure involved degassation of the sample under high vacuum for 3 h at 200 °C, cooling of the sample, and putting the solution of CH3NH3PbBr3 in DMF, after which it was treated with inert gas (N2), as an overpressure which enabled the filling of the nanotubes with perovskite material. The diffuse reflectance spectroscopy measurement of the sample proved that deposition of CH3NH3PbBr3 improves the absorption properties of TiO2 nanotubes. The I-V characteristics of the sample showed photodiode behavior and characteristic hysteresis curve for perovskite material. The value of current under visible light for the sample without preconditioning was 46 mA, while after preconditioning value of current was 76 mA. The results indicate that a perovskite photodiode with increased contact between TiO2 and perovskite was made, which is the basis for future solar cell construction.

Introduction/Objective. Stress is proposed as one of the risk factors linked to periodontal disease. The COVID-19 pandemic has a significant negative impact in population on mental and somatic health. This study aimed to examine the possible association between COVID-19 resultant stress and periodontal health. Methods. An observational pilot study was conducted from March 2020 to October 2021 and included 202 participants. Participants graded their stress level using the Perceived Stress Scale (PSS). Periodontal Disease Index and Clinical Attachment Level were determined. Participants were categorized into following groups: Ia (low stress), IIa (moderate stress), IIIa (high stress) and Ib (healthy parodontium), IIb (mild periodontal disease), IIIb (severe periodontal disease). The cause/effect relationship between stress and health was measured. Results. The results indicated a statistically significant difference between the groups classified according to the stress level concerning values of all the measured parameters. The Poisson regression analysis showed that in both models, crude and adjusted, periodontal health-related covariables were higher in subjects perceiving greater stress (Periodontal Disease Index – Pradjusted = 1.042, 95% CI [1.030–1.055] and Clinical Attachment Level – PRadjusted = 1.108, 95% CI [1.094–1.122]). Conslusion. During COVID-19 pandemic increased stress has a negative impact on mental health and may result in the deterioration of the entire oral cavity’s health, including the periodontium.

Secondary plant metabolites with allelopathic activity or phytotoxicity could be biotechnologically important, serving as a source of allelochemicals, and thus contributing to the agro-industrial sector. The objective of this study was to use the obtained common walnut (Juglans regia L.) and bitter dock (Rumex obtusifolius L.) leaves extracts rich in phenolic compounds, i.e. with high antioxidant potential, and to identify their phytotoxicity to Setaria glauca (L.) P. Beauv. and Sorghum halepense (L.) Pers. weed seedlings grown in vitro. The obtained plant extracts had remarkably high affinity for scavenging free radicals, having DPPH IC 50 values of 0. 127 mg/ml for common walnut leaf extract and 0.194 mg/ml for bitter dock leaf extract. Ferric reducing antioxidant power of the extracts was also high, FRAP value of the common walnut leaf extract was 384.4 ± 8. 1 mmol Fe 2+ /g dry mass, and of the bitter dock leaf extract 321.6 ± 2.5 mmol Fe 2+ /g dry mass. At the highest used concentration, common walnut leaf extract reduced germination of S. glauca by 67.3%, while bitter dock leaf extract reduced germination of that weed by 54.5%. Shoot length of S. glauca was inhibited 80.7% when subjected to common walnut leaf extract, and 78.2% under the influence of bitter dock leaf extract, and its root length was inhibited 96.4% and 93. 1% respectively. Germination of S. halepense was inhibited 100% under the influence of the obtained common walnut leaf extract at its highest test concentration, and 79.2% when subjected to bitter dock leaf extract at the same concentration. Shoot length of this weed was reduced 100% after treatment with common walnut leaf extract, and 93.7% when subjected to bitter dock leaf extract. Root length was reduced 100% and 99.3%, respectively. Overall, the extracts demonstrated pronounced antioxidant activity and remarkable allelopathic potential.