Osteoporosis is a progressive bone disorder that can be infl uenced by many diff erent factors. A cross-sectional study has been conducted with the aim to assess the prevalence of risk factors as well as to identify the possible causes of improvement of the disease. Th e study population consisted of 97 women older than 35 who had previously been diagnosed with osteoporosis. Dualenergy X-ray Absorptiometry (DXA) scan was used to determine bone mineral density (BMD) in order to assess the current state of the disease. Th e participants were asked to complete a standardized IOF (International Osteoporosis Foundation) questionnaire. According to BMD measurements, 24.7% of women had normal bone density while 18.6% had T-score lower than -2.5. Th ere was a statistically signifi cant correlation between T-score and the history of previous bone fractures. Besides, a relatively high prevalence of certain risk factors (such as underweight, early menopause, oophorectomy, thyroid and parathyroid disorders etc.) was observed in woman with osteoporosis.

Deterministic and stochastic models of Brownian motion in ferrofluids are of interest to researchers, especially those related to drug delivery systems. The Brownian motion of nanoparticles in a ferrofluid environment was theoretically analyzed in this research. The state of the art in clinical drug delivery systems using ferromagnetic particles is briefly presented. The motion of the nanoparticles in an external field and as a random variable is elaborated by presenting a theoretical model. We analyzed the theoretical model and performed computer simulation by using Maple software. We used simple low-dimensional deterministic systems that can exhibit diffusive behavior. The ferrofluid in the gravitational field without the presence of an external magnetic field in the xy plane was observed. Control parameter p was mapped as related to the fluid viscosity. Computer simulation showed that nanoparticles can exhibit deterministic patterns in a chaotic model for certain values of the control parameter p. Linear motion of the particles was observed for certain values of the parameter p, and for other values of p, the particles move randomly without any rule. Based on our numerical simulation, it can be concluded that the motion of nanoparticles could be controlled by inherent material properties and properties of the surrounding media, meaning that the delivery of drugs could possibly be executed by a ferrofluid without an exogenous power propulsion strategy. However, further studies are still needed.

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Electrospinning is highly used technique in the tissue engineering field, particularly in biomedical application [1]. The constricted concepts of this process are based on generate nonwoven nanofibers. The method involves high voltage electricity which is applied to the liquid solution and a collector, which lets the solution force out from a nozzle forming a jet. The jet formed fibers under influence of electrostatic forces concentrated and deposited these on the collector. Main objective of this study was to fabricate gelatin scaffolds with micro/nano-scale for successful wound dressing. Gelatin can mimic the chemical composition, physical structure and structure of the native skin extracellular matrix (ECM). However, the first and main principle in this study is the optimization of parameters of the electrospinning process. The used parameters have a crucial role in obtaining suitable fibers for further cell seeding and cell growth in vitro. With the use of series of various biocompatible polymers and solvents, solutions were tested in various electrospinning settings in order to produce microscale fibers. The scaffolds were analysed with scanning electron microscope images for fiber diameter measurement.