Vesna Velickovic, Sladjana Simovic, Tatjana Sarenac, Natasa Mihailovic, Svetlana Ristic and Sandra Zivanović
The aim of this study was to determine the frequency of ocular symptoms and compare the demographic and clinical characteristics in AR patients depending on sensitisation to various types of aeroallergens.
Allergic rhinitis is defined as an IgE-mediated inflammation of the lining of the nose that is characterized by nasal symptoms, including nasal congestion, sneezing, itching of nose and runny nose. Patients suffering from allergic rhinitis frequently experience ocular symptoms such as ocular redness, eye itching and tears. The frequency of ocular symptoms in our study population was 27,6%. No statistical significance was found in the mean ages of the patients who did or did not experience ocular symptoms p>0,05 (p=0,243). Our results indicated that there were no statistical differences (p>0,05) among the groups of allergic rhinitis patients based on experiencing nasal symptoms according to the types of aeroallergens. Our results indicated that there were significant experiences of ocular symptoms in patients who were sensitised to outdoor aeroallergens (p<0,001) and significant sensitisation to both outdoor and indoor aeroallergens (p<0,05). Experiencing the examined ocular symptoms, including ocular redness, eye itching and tears, demonstrated highly statistical significance (p<0,001) among the groups of allergic rhinitis patients who were sensitised to indoor aeroallergens and outdoor aeroallergens, and there was statistical significance (p<0,05) among the groups of allergic rhinitis patients who were sensitised to indoor aeroallergens and both types of aeroallergens (indoor and outdoor).
Ocular symptoms are more common in patients who are sensitised to outdoor aeroallergens.
Sandra Veličković, Slavica Miladinović, Blaža Stojanović, Ružica R. Nikolić, Branislav Hadzima and Dušan Arsić
Hybrid materials with the metal matrix are important engineering materials due to their outstanding mechanical and tribological properties. Here are presented selected tribological properties of the hybrid composites with the matrix made of aluminum alloy and reinforced by the silicon carbide and graphite particles. The tribological characteristics of such materials are superior to characteristics of the matrix – the aluminum alloy, as well as to characteristics of the classical metal-matrix composites with a single reinforcing material. Those characteristics depend on the volume fractions of the reinforcing components, sizes of the reinforcing particles, as well as on the fabrication process of the hybrid composites. The considered tribological characteristics are the friction coefficient and the wear rate as functions of the load levels and the volume fractions of the graphite and the SiC particles. The wear rate increases with increase of the load and the Gr particles content and with reduction of the SiC particles content. The friction coefficient increases with the load, as well as with the SiC particles content increase.