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Multifunctional Sr,Mg doped mesoporous bioactive glass nanoparticles
No full text: Recently, mesoporous bioactive glass particles (MBGs) doped with therapeutical ions have emerged as a promising biomaterial with ability to simultaneously deliver drugs and ions, leading to synergistic outcomes. Sr and Mg ions are widely investigated in ion-doping approach of bioceramics and bioactive glasses due to their ability to stimulate osteogenesis and angiogenesis. The co-doping of MBGs with Sr and Mg might lead to accelerated bone regeneration, however the presence of dopant ions can also influence the mesoporosity of MBGNs, and thus affect bioactivity and drug release behaviour. The objective of this study was to investigate the influence of Sr,Mg co-doping on the textural properties, drug delivery, as well as pro-osteogenic and pro-angiogenic potential of MBGs.ExcellMater Conference 2024: Innovative Biomaterials for Novel Medical Devices, Belgrade, Serbia, April 10-12, 202
Numerička studija uticaja parametara pregrade na polje protoka i potrošnju energije
No full textThe current state of research in the field of stirred tanks across diverse industrial sectors places significant focus on the design of stirred tanks, turbine blades, and baffles. This research involves a numerical investigation which focuses on examining the velocity field in a tank subjected to mechanical agitation through a Rushton turbine, particularly in turbulent flow conditions. The study utilises a Newtonian fluid as the working medium and explores the influence of various factors, including the number and placement of baffles. The investigation employs a specialised calculation code called CFX 18.0. The numerical results are analysed to determine and discuss the impact of geometrical parameters, such as the number two, three and four shape, and spacing between vertical tubular baffles, on the power characteristics obtained for each impeller type.Trenutno stanje istraživanja u oblasti rezervoara sa mešanjem u različitim industrijskim sektorima stavlja značajan fokus na dizajn rezervoara sa mešanjem, lopatica turbina i pregrada. Ovo istraživanje uključuje numeričko istraživanje, koje se fokusira na ispitivanje polja brzina u rezervoaru koji je podvrgnut mehaničkom mešanju kroz Raštonovu turbinu, posebno u uslovima turbulentnog strujanja. Studija koristi njutnovsku tečnost kao radni medijum i istražuje uticaj različitih faktora, uključujući broj i postavljanje pregrada. Istraživanje koristi specijalizovani računski program pod nazivom CFKS 18.0. Numerički rezultati su analizirani da bi se odredio i razmotrio uticaj geometrijskih parametara, kao što su oblik broj dva, tri i četiri, kao i razmak između vertikalnih cevastih pregrada, na energetske karakteristike dobijene za svaki tip radnog kola
Determination of growth promother progesterone in chicken eggs
No full textAnimal products are a major source of human exposure to hormones that could be harmful to health
if present in elevated concentrations. In this paper, the development and optimization of the liquid
chromatography–tandem mass spectrometry (LC–MS/MS) method for the determination of
progesterone in chicken eggs were described. Egg samples were prepared using ultrasonic
extraction and clean-up with Oasis HLB cartridges. Extracts were analyzed by LC–MS/MS with
atmospheric pressure chemical ionization. The developed and optimized method provided high
recoveries, with RSDs lower than 4%. The method was applied to the analysis of progesterone in
four different chicken egg types. Progesterone was detected in all investigated samples in the
concentration range from 123 ng g–1 to 206 ng g–1. Compared to the acceptable daily intake values
(0–30 μg (kg bw)–1), the progesterone levels found in the tested eggs are not of concern
Uncovering Metal-Decorated TiO2 Photocatalysts for Ciprofloxacin Degradation—A Combined Experimental and DFT Study
No full textOptimization of the efficiency of the photocatalytic degradation of organic and pharmaceutical pollutants represents a matter of fundamental and practical interest. The present experimental and
DFT study deals with evaluation of OH radical binding energy as a simple computational descriptor
of the catalytic activity of d-metal-decorated TiO2 photocatalysts for the photodegradation of the
widely used antibiotic ciprofloxacin. Five d-metals commonly used in catalytic materials (Zr, Pt, Pd,
Fe, and Cu) were deposited on the TiO2 surface, and the obtained photocatalysts were characterized
experimentally (XRPD, ICP-OES, and SEM) and theoretically (DFT). Attention was also paid to
the mechanistic insights and degradation byproducts (based on UV-Vis spectrometry and LC/MS
analysis) in order to obtain systematic insight into their structure/performance relationships and
confirm the proposed model of the degradation process based on OH radical reactivity
In vitro skin permeation of flavonoid esters enzymatically derived from natural oils: release mechanism from gel emulsion, stability, and dermatological compatibility
No full textDue to their broad spectrum of biological activities and attractive pharmacological properties, flavonoids are very promising molecules for application in skin care products. In this study, phloridzin and naringin medium- and long-chain fatty acid esters were enzymatically synthesized in reaction with natural oils (coconut and linseed oil) and in vitro transdermal delivery of synthesized esters through artificial Strat-M® membrane was investigated. Experimental results were succesfully fitted using Peppas and Sahlin model which includes the lag phase. Release kinetics of all examined flavonoid esters from gel emulsions through the membrane depended on both diffusion and polymer relaxation effect (0.5<n < 1). The estimated effective diffusion coefficients ranged from 0.168·10-8 to 6.149·10-8 cm2 s-1 for phloridzin esters and from 0.116·10-8 to 4.210·10-8 cm2 s-1 for naringin esters. The effective diffusion coefficients decreased with the increase in ester molecular weight indicating the size-dependent diffusion. All formulation showed good stability, excellent hydration effect, and excellent dermatological compatibility without irritating effect. It can be concluded that gel emulsions with a mixture of flavonoid esters enzymatically synthesized in reaction with vegetable oils can be effectively topically applied as a skin care products
Adsorpcija lekova iz vode primenom modifikovanog vlaknastog tekstilnog otpada
No full textTextile industry is a significant environmental polluter, generating vast
amounts of waste during production, processing, dyeing, and distribution. Disposing of
chemical and solid textile waste poses serious risks to soil, water, and air quality. In order
to mitigate this inconvenience, solid textile waste can be reused through redesign or
recycling methods. One such method involves repurposing textile waste as adsorbent or as
a raw material for carbon adsorbent preparation. In this study, fibrous textile waste, waste
cotton yarns and flax fibers were utilized as cost-effective resources for carbon material
production. Carbon materials were derived from waste fibers and yarns through
carbonization and subsequent activation using KOH as an activating agent. The
adsorption characteristics of newly prepared materials were examined through the
adsorption of various drugs from water. Factors such as contact time, initial concentration,
and pH of the drug mixture in an aqueous solution were studied to understand their impact
on the adsorption capacity of carbon adsorbents. The obtained results were analyzed using
pseudo-first and pseudo-second order kinetics models, Freundlich and Langmuir
isotherms. It has been shown that carbon materials obtained by the activation of cotton
yarn and flax fibers can be used as highly efficient adsorbents for the rapid removal of
drugs from water.Tekstilna industrija je jedan od najvećih zagađivača životne sredine zbog
ogromnih količina otpada koji se generišu tokom proizvodnje, obrade, bojenja i
distribucije. Odlaganje hemijskog i čvrstog tekstilnog otpada nosi ozbiljne rizike po
kvalitet zemljišta, vode i vazduha. Da bi se ublažio negativni uticaj tekstilne industrije na
životnu sredinu, čvrsti tekstilni otpad se može ponovo upotrebiti korišćenjem metoda
redizajniranja ili recikliranja. Jedan od vidova ponovne upotrebe tekstilnog otpada je
njegovo korišćenje kao adsorbenta ili sirovine za proizvodnju ugljeničnih adsorbenata. U
cilju smanjenja količine vlaknastog tekstilnog otpada, u ovom radu je ispitana mogućnost
njegovog korišćenja za dobijanje ugljeničnih adsorbenata. Primenom metoda
karbonizacije i naknadne aktivacije u prisustvu KOH kao aktivirajućeg agensa, polazeći
od pamučnog prediva i vlakana lana dobijeni su ugljenični materijali. Adsorpcione
karakteristike dobijenih materijala ispitivane su adsorpcijom ostataka kardiovaskularnih
lekova iz vode. Ispitan je uticaj vremena kontakta, početne koncentracije i početne pH
vrednosti smeše lekova na adsorpcioni kapacitet pripremljenih adsorbenata. Dobijeni
rezultati su analizirani korišćenjem kinetičkih modela pseudo-prvog i pseudo-drugog reda,
kao i Frojndlihove i Lengmirove adsorpcione izoterme. Pokazano je da se karbonizacijom
i naknadnom aktivacijom pamučnog prediva i vlakana lana mogu dobiti visoko efikasni
adsorbenti za brzo uklanjanje lekova iz vode
Zooplankton studies in Boka Kotorska Bay and the Southern Adriatic – Appendicularia
No full textAim: Analysis of zooplankton biodiversity in order to determine the southern Adriatic
coastal system fluctuations influenced by human activities.
Material and methods: This study is based on the analysis of zooplankton samples
collected from three shallow stations near seafood farming areas and four stations in the
central regions of each bay within the Boka Kotorska Bay complex, as well as from two
stations in the southern Adriatic. Sample collection was conducted monthly throughout
2009. Zooplankton was obtained using Nansen nets with mesh sizes of 100 and 150
microns. Concurrently, physical parameters were measured: temperature [°C], salinity
[‰], pH factor, dissolved O2
concentration [%], Secchi depth and sea colour (Forel scale
I–XXI). ..
A decision support tool for municipal waste landfills’ management
No full textMost developing countries are disposing of large amounts of biodegradable waste in landfills. Generated landfill gas (LFG) can have negative impact on climate changes but it also can be used as a renewable energy resource. This paper aims to present an application (DeponIS) which supports business processes of waste management on municipal landfills in Serbian conditions. That way better prediction of available LFG quantities can be achieved. This application can help management decisions in several areas: available operational data in real time and strategical decisions based on projections about quantity of LFG in future. It can also be used as a generator for annual reports for Environmental Protection Agency and be in accordance with the polluter pays principle.5th International Conference on Environmental Design and Health (ICED2024), 18-20 October 2024, Athens, Greece and Onlin
Geochemical Profiles of Deep Sediment Layers from the Kolubara District (Western Serbia): Contamination Status and Associated Risks of Heavy Metals
No full textGlobal awareness of the harmful effects of heavy metal contamination in soil has increasedsignificantly. Understanding the vertical distribution of oxides and elements is vital for tracing the historyof potential contamination. Thus, this study focuses on deep sediment cores primarily composedof quartz and clay minerals from a small village in the western Tamnava Basin of Serbia. The aim wasto assess the vertical distribution of 11 oxides and 21 elements and the ecological risks of eight heavymetals by analyzing 250 sediment samples from 18 boreholes at depths ranging from 5 to 58.5 m.Deep sediment core samples were analyzed using energy-dispersive X-ray fluorescence spectrometry(ED-XRF). Potential contamination levels were evaluated within the study area. Additionally, sampleswere analyzed for total carbonate and organic carbon contents and particles retained on a 0.063 mmsieve. Higher than permitted concentrations of vanadium (V), thallium (Tl), and barium (Ba) werefound. Notably, this zone is located above a proposed lithium and boron mine in Gornje Nedeljice,making it crucial for monitoring efforts. Even if mining operations do not commence, examiningthe deep sediment layers in this rural area remains important. This study offers novel and valuabledata on the concentrations of potentially toxic elements in undisturbed deep sediment, serving as abenchmark for future comparisons
Modulation Of Human Mycobiota As A Tool For Promoting Health [Predavanje po pozivu štampano u izvodu]
No full textHuman microbiota is a complex microbial ecosystem that colonizes the human body. The densest microbial ecosystem is present in the colon, which can be seen as a bioreactor, while colonic microbiota can be perceived as a microbial organ of the human body. Colonic microbiota performs numerous metabolic functions that complement human metabolism and systemically impact health. In this complex ecosystem, bacteria are the dominant fraction but other types of organisms belonging to archea, fungi (including yeast) and protozoa are present too. Recent data indicates that colonic fungi (i.e. mycobiota) are a sub-abundant but highly relevant component of the microbiota. The bacterial and fungal compositions are strongly interconnected and in several intestinal diseases an abnormal mycobiota composition along with bacterial dysbiosis was detected. The most prevalent and the most dominant genera of human mycobiota are Saccharomyces, Malassezia, Candida, Cyberlindnera, Cladosporium, Debaryomyces and Pichia.Dysbiosis of mycobiota was detected in celiac disease, inflammatory bowel disease and hepatocellular carcinoma, while an experiment on a mouse model showed that mycobiota dysbiosis can promote colon cancer by changing metabolism of subepithelial macrophages. Mycobiota is relatively unstable and, presumably, strongly influenced by the diet and other environmental factors. Therefore, for treatment of mycobiota dysbiosis, in addition to antifungal drugs, dietary supplements can be used. Polyphenols are bioactive plant metabolites, which are classified as prebiotics. These molecules have the ability to promote the growth of beneficial and inhibit the growth of pathogenic microorganisms. While this feature has been long known for bacteria, in recent studies we show that several medicinal plant polyphenols can stimulate the growth of the probiotic yeast Saccharomyces boularii, and suppress the growth of the opportunistic pathogen C. аlbicans. Based on this preliminary in vitro data, treatments with traditional medicinal plants might offer a pave a way to alternative approach to currently incurable diseases.Predavanje po pozivu (Mirjana Rajilić-Stojanović