7 research outputs found

    The origin of lead artifacts from Novae: applications of Pb isotopes in identifying the provenance of Roman artifacts from N. Bulgaria

    No full text
    Abstract This study identifies the lead ores used to produce lead artifacts used by the Romans between the first and eighth centuries AD during the construction of the fort and then the town of Novae (N. Bulgaria). For this purpose, lead samples were taken from pipes, joints of columns and pedestals, and from a lead ingot. The samples were analyzed for lead isotopes and the results were compared to literature data for Roman mines from what is now Bulgaria, Greece, North Macedonia, Montenegro, Bosnia and Herzegovina, Italy, Germany, and Romania. Pb isotope results indicate that during the earlier stages of Novae's establishment, lead was most likely supplied from several different mines located in the Balkan area. Several samples also show Pb isotopes indicating mixing of lead from mines in the Balkan area. Then in the fourth—fifth century AD lead began to be supplied mainly from mines located in NW Bulgaria, with one sample possibly from deposits in German. This is evidenced by the matching of the results obtained for the ores to the data for deposits from these regions. Two possibly recycled samples were also identified. Deposits from other European regions did not match samples from Novae, indicating that majority of the lead was sourced from mines in the Balkan region

    Efficient, low-cost optical coupling mechanism for TiO2-SiO2 sol-gel derived slab waveguide surface grating coupler sensors

    No full text
    We present an optical signal coupling scheme for slab waveguide surface grating coupler sensors. The proposed solution is based on the use of polymer microlenses. In this work we analyze two types of compact polymer lenses: the aspheric plano-convex lenses and Fresnel lenses. The feasibility of the proposed scheme is demonstrated by the experimental investigation into the optical signal coupling to the test structure of TiO2-SiO2 slab waveguide surface grating coupler using both types of lenses

    Metallic Nanoparticles and Core-Shell Nanosystems in the Treatment, Diagnosis, and Prevention of Parasitic Diseases

    No full text
    The usage of nanotechnology in the fight against parasitic diseases is in the early stages of development, but it brings hopes that this new field will provide a solution to target the early stages of parasitosis, compensate for the lack of vaccines for most parasitic diseases, and also provide new treatment options for diseases in which parasites show increased resistance to current drugs. The huge physicochemical diversity of nanomaterials developed so far, mainly for antibacterial and anti-cancer therapies, requires additional studies to determine their antiparasitic potential. When designing metallic nanoparticles (MeNPs) and specific nanosystems, such as complexes of MeNPs, with the shell of attached drugs, several physicochemical properties need to be considered. The most important are: size, shape, surface charge, type of surfactants that control their dispersion, and shell molecules that should assure specific molecular interaction with targeted molecules of parasites’ cells. Therefore, it can be expected that the development of antiparasitic drugs using strategies provided by nanotechnology and the use of nanomaterials for diagnostic purposes will soon provide new and effective methods of antiparasitic therapy and effective diagnostic tools that will improve the prevention and reduce the morbidity and mortality caused by these diseases

    Efficacy of Ceragenins in Controlling the Growth of Oral Microorganisms: Implications for Oral Hygiene Management

    No full text
    Ensuring proper dental hygiene is of paramount importance for individuals’ general well-being, particularly for patients receiving medical care. There is a prevailing utilization of conventional oral hygiene items, including toothbrushes and mouthwashes, which have gained widespread acceptance; nevertheless, their limitations encourage investigating novel options in this domain. Our study indicates that ceragenins (CSAs) being lipid analogs of host defense peptides, well-recognized for their wide-ranging antimicrobial properties, may be a potentially efficacious means to augment oral hygiene in hospitalized individuals. We demonstrate that ceragenins CSA-13, CSA-44, and CSA-131 as well as undescribed to date CSA-255 display potent antimicrobial activities against isolates of fungi, aerobic, and anaerobic bacteria from Candida, Streptococcus, Enterococcus, and Bacteroides species, which are well-recognized representatives of microbes found in the oral cavity. These effects were further confirmed against mono- and dual-species fungal and bacterial biofilms. While the ceragenins showed similar or slightly diminished efficacy compared to commercially available mouthwashes, they demonstrated a highly favorable toxicity profile toward host cells, that may translate into better maintenance of host mucosal membrane stability. This suggests that incorporating ceragenins into oral hygiene products could be a valuable strategy for reducing the risk of both oral cavity-localized and secondary systemic infections and for improving the overall health outcomes of individuals receiving medical treatment
    corecore