Thin film deposition of multilayers on silicon substrate laser pre-patterned

In scientific and commericial needs, there was a great demand for the modification of biomaterials that would replace damaged tissue in the body. Today, titanium alloys are mostly used for these purposes in combination with metals of similar physicochemical properties. In this context, there is an increased interest in the development of novel biocompatible materials with enhanced surface interface. The experimental results of a Ti/Zr/Ti thin film system deposited on a substrate pre-patterned by a dynamic femtosecond laser are presented. Surface pattering with micrometre characteristics in the form of spikes is being investigated in order to generate arrayed surface patterns for biomedical pruposes. Femtosecond laser pulses were used to acquire black silicon surfaces adorned with conical structures under 0,65 bar in SF6 ambient pressure. The silicon surface contains high aspect ratio spikes with conical morphologies of about 2μm, 400 angle opening, and 13·106 cm-2 density that is roughly uniform over the treatment area. Ion sputtering was employed on sech a prepared surface to make a unique composite thin film composed of two layers of Ti and a subsurface layer of Zr. The deposited Ti/Zr/Ti cpomiste has a thickness of 400 nm. The composition and surface morphology were evaluated using FESEM-EDS and XPS methods. Transmission electron spectroscopy and energy dispersive X-ray spectroscopy demonstrated that post-deposition of Ti/Zr/Ti over Si laser-patterned resulted in diffusion of Ti and Zr layers.Twenty-First Young Researchers’ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 – December 1, 2023, Belgrade, Serbi

Identifikacija, analiza i klasifikacija kretanja zgloba kolena

Gait is a fundamental human activity. One of the main joints that participate in walking process is knee joint. This joint is considered to be the largest and most complex joint in human body. This complexity comes from possibility of translation and rotation along and around all axes. All of these movements have corresponding pattern. Main purpose of this doctoral thesis is to identify and analyze standard values and patterns of basic movement parameters of healthy individuals. Experimental research was done in Clinical Centre Kragujevac on healthy individuals and on patients with deficient/diseased soft tissue and/or cartilaginous knee structures. Three systems were used for acquiring data – OptiTrack, Kinetic XBOX camera and simple web camera. Mathematical model of a knee was created for calculating identified gait parameters. It is concluded, with a help of statistical methods, that there is a significant difference in gait pattern between healthy individuals and patients with deficient/diseased knee joint structures. For the purpose of getting objective results, models for predicting/classification (based on logistic regression and neural network models) possible damage/illness of knee joint based on walk parameters values and gait curves were created. Models for predicting/classification are valued by diagnostic tests. Results showed that this approach can help in better understanding of processes in knee joint that occur during walking, can help to achieve objectivity in walking process evaluation, improve rehabilitation process depending on level of recovery of the patient, etc

High-accuracy quasistatic numerical model for bodies of revolution tailored for RF measurements of dielectric parameters

We have developed rotationally symmetrical coaxial chambers for measurements of dielectric parameters of disk-shaped samples, in the frequency range from 1 MHz to several hundred MHz. The reflection coefficient of the chamber is measured and the dielectric parameters are hence extracted utilizing a high-accuracy quasistatic numerical model of the chamber and the sample. We present this model, which is based on the method-of-moments solution of a set of integral equations for composite metallic and dielectric bodies. The equations are tailored to bodies of revolution. The model is efficient and accurate so that the major contribution of the measurement uncertainty comes from the measurement hardware

State and Science: Yugoslav Identity on the Third Slavic Congress of Geographers and Ethnologists in 1930 (Abstract)

Autorice se bave propitivanjem uloge intelektualaca u konstrukciji nadnacionalnoga jugoslavenskog identiteta u Kraljevini Jugoslaviji. Kao primjer prikazuju događanja u vezi s organizacijom i provedbom malo poznatoga i do sada neobrađivanog III. kongresa slavenskih geografa i etnografa održanog 1930. godine.The authors question the role of intelligentsia in the construction of supranational Yugoslav identity in the Kingdom of Yugoslavia. As a case study, the authors present events which accompanied the organization and realization of, a hardly familiar and never analyzed, Third Congress of Slavic Geographers and Ethnographers held in 1930

Structural and electrical properties of tungsten - titanium sputtered coatings

Correlation of structural and electrical properties of W-Ti thin films deposited by sputtered were studies. The results have shown that changes of grain size are in agreement with the sheet resistance behavior as a function of the thin films thickness. The characteristic change of grain size and sheet resistance are obtained in thickness interval between 100 – 150 nmPhysical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

Binding of 17-substituted 16-nitrile 16,17-secoestrane Compounds to Estrogen Receptors – „In Vitro“ and „In Silico“ Study

About 75% of breast cancers express estrogen receptors (ERs), which is a good base for an efficient endocrine therapy. This gives the opportunity for the treatment of patients with antiestrogens, compounds that bind to the ERs and thus compete to estradiol (E2), preventing its action in progression of estrogen-depending cancers. Here we present results of testing the effect of the modified steroids, namely 17-substituted 16-nitrile 16,17-secoestrane compounds on the E2-ER complex forming, its stability, nuclear translocation and binding to DNA. Almost all compounds in moderate to high rate induced lower forming of this complex, destabilizing it – they increased Kd of this complex and decreased number of binding sites. Complex formed in the presence of some test secosteroids could pass to the nucleus, while other compounds inhibited translocation. In the presence of some compounds binding of the formed complex E2-ER to DNA was noticed. Docking followed molecular dynamics simulation was performed to reveal binding mode of E2 to ER in the presence of test secosteroids. Amino acids important for binding process and complex stabilization were detected. Analysis of the simulation data allowed identifying key amino acids and type of binding of the secoestrane compounds, important for high affinity binding of the steroidal compounds

THERAPEUTIC ALTERNATIVES OF NATURAL COMPOUNDS IN TREATMENT OF CANDIDA-ASSOCIATED DENTURE STOMATITIS

Denture stomatitis is a common inflammatory reaction affecting denture wearers, multifactorial etiology, which is usually associated with Candida species, particularly Candida albicans. The treatment of Candida-associated denture stomatitis (CADS) is difficult and complex due to its multifactorial etiology, common recurrences, as well as the lack of antifungal drug efficacy. This review aims to critically discuss several key factors affecting adhesion and biofilm formation of Candida species on acrylic surface, as well as the use of herbs, proposed as an alternative in the treatment of CADS. Many factors affect adhesion and biofilm formation of Candida spp. on acrylic surfaces, such as surface roughness of the inner surface of the prosthesis, salivary pellicle, hydrophobic and electrostatic interactions. Having in mind that denture stomatitis is a common disease in total denture wearer, that it is most common in fungal etiology and that biofilm development increases yeast resistance, application of non-synthetic, completely natural substances, such as essential oils and extracts, may be suggested as a promising alternative for treatment of CADS

Karakterizacija autohtonih sojeva Lactobacillus paracasei na potencijalne probiotičke sposobnosti

Lactic acid bacteria strains isolated from traditional made cheeses constitute a reservoir of unexplored potential in biotechnology. In this study four autochthonous lactobacilli strains, isolated from traditional white brined cheeses and identified as Lactobacillus paracasei (08, 564, 05 and 02), were investigated on potential probiotic ability. The investigation comprised sensitivity to simulated gastrointestinal tract conditions, antimicrobial activity against wide range of pathogens, antibiotic resistance as well as autoaggregation ability. Lactobacillus rhamnosus GG was used as referent strain. Three tested strains grew well in simulated gastrointestinal conditions, but their sensitivity was greater on bile acids and pancreatin compared with pepsin low pH 2.5. The examined strains had different sensitivity to antibiotics, but three strains showed very good antimicrobial activity to pathogens. All strains demonstrated very good autoaggregation ability. For three of four examined strains of Lb. paracasei probiotic potential was similar with referent strain Lb. rhamnosus GG, determined in vitro.Bakterije mliječne kiseline izolirane iz tradicionalnih sireva predstavljaju neiscrpan potencijal u biotehnologiji. U ovom radu 4 soja laktobacila, izolirana iz autohtonih bijelih sireva u salamuri i identificirana kao Lactobacillus paracasei (08, 564, 05 and 02), ispitivana su na potencijalne probiotičke sposobnosti. Ispitivanje je obuhvatilo osjetljivost na simulirane gastrointestinalne uvjete, antimikrobnu aktivnost u odnosu na patogene, antibiotsku rezistentnost i sposobnost autoagregacije. Lactobacillus rhamnosus GG upotrijebljen je kao referentni soj. Tri testirana soja dobro su rasla u simuliranim gastrointestinalnim uvjetima, ali je njihova osjetljivost bila veća u prisustvu žučne kiseline i pankreatina u usporedbi s pepsinom niskog pH 2,5. Ispitivani sojevi pokazali su različitu osjetljivost na antibiotike, a 3 soja su pokazala dobru antimikrobnu aktivnost u odnosu na patogene. Svi su sojevi pokazali visoku sposobnost autoagregacije. Od 4 ispitana soja Lb. paracsei, tri su pokazala dobar probiotički potencijal u usporedbi s referentnim sojem Lb. rhamnosus GG, in vitro uvjetima