Influence of Adhesion Additives on the Grip of Bitumen to Stone Material and Water Resistance of Asphalt Concrete

The primary condition for obtaining high-quality asphalt concrete is good adhesion of bitumen to mineral material, which is ensured by good wetting and chemical interaction of the components. The solution to this problem is achieved by using adhesive additives with surface-active properties that enhance adsorption and chemisorption processes on the surface of the mineral material. This paper presents the results of an experimental study to determine the effect of adhesive additives on the adhesion of bitumen to stone material. For this work, bitumen of the BND 100/130 brand with adhesive additives “Wetfix Be”, Amdor-9 and AlfaDob were used. The elemental and phase compositions of the stone material of 10 quarries of the Republic of Kazakhstan were determined using X-ray fluorescence and X-ray phase analyses. The elemental composition showed the content of oxides: CaO, MgO, Fe2O3, Al2O3, and oxides: SiO2, K2O, Na2O, CO2 in minerals. Based on the results of the X-ray phase analysis, the percentage mineralogical composition of stone materials was determined and the total silicon dioxide was calculated based on the chemical formula corresponding to certain minerals

Diagnostic value of macular blood flow in normal tension glaucoma

A.Sh. Zagidullina1, V.U. Galimova1, A.I. Arslanova1,2, A.R. Nugmanova1 1Bashkir State Medical University, Ufa, Russian Federation 2City Clinical Hospital No. 8, Ufa, Russian Federation Aim: to evaluate macular microcirculation in patients with early newly diagnosed normal tension glaucoma (NTG) and primary open-angle glaucoma (POAG) with elevated IOP using optical coherence tomography angiography (OCTA). Patients and Methods: patients aged 45–65 years with early newly diagnosed NTG (35 patients, 35 eyes) or POAG with elevated IOP (43 patients, 43 eyes) and healthy individuals without ocular disorders (n=50) were examined. All patients underwent OCTA by measuring vascular density (VD, %) using the ETDRS grid (central Fovea and Parafovea) and retinal thick-ness using the Angio Retina 3.0 protocol of the Optovue XR Avanti with the AngioVue function (Optovue, USA). Results: in patients with NTG and POAG, a decrease in vascular density in the superficial choroid plexus was detected. In patients with NTG, retinal thickness in the Fovea, Parafovea, Inferior, and Nasal quadrants was lower than that in the control group and correlated with VD in the Fovea and superior Parafovea of the superficial choroid plexus. The severity of focal losses of the retinal ganglion cell complex was lower than that in the control group and demonstrated a significant weak negative correlation (r=-0.487, p&lt;0.01) with the vascular density index in the Fovea of the superficial choroid plexus. In patients with POAG, retinal thickness in the Fovea and Parafovea was also reduced and correlated with vascular density in the temporal and inferior Parafovea. The severity of global losses of the retinal ganglion cell complex demonstrated a weak negative correlation (r=-0.464, p&lt;0.01) with microcirculation density in the Fovea of the superficial retinal choroid plexus. Conclusion: OCTA revealed a decrease in vascular density in the superficial choroid plexus in early glaucoma. Moreover, a significant difference between NTG and POAG in the Fovea and Parafovea was revealed. Our study established the predominance of vascular changes in patients with NTG. OCTA parameters of the superficial choroid plexus identify microcircula-tion abnormalities at early glaucomatous damage. Keywords: primary open-angle glaucoma, normal tension glaucoma, OCT, optical coher-ence tomography angiography, vascular density index. For citation: Zagidullina A.Sh., Galimova V.U., Arslanova A.I., Nugmanova A.R. Diagnostic value of macular blood flow in normal tension glaucoma. Russian Journal of Clinical Ophthalmology. 2023;23(4):174–180 (in Russ.). DOI: 10.32364/2311-7729-2023-23-4-1. </p

Nanostructured polyelectrolyte complexes based on water-soluble thiacalix[4]Arene and pillar[5]arene: Self-assembly in micelleplexes and polyplexes at packaging DNA

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Controlling the self-assembly of polyfunctional compounds in interpolyelectrolyte aggregates is an extremely challenging task. The use of macrocyclic compounds offers new opportunities in design of a new generation of mixed nanoparticles. This approach allows creating aggregates with multivalent molecular recognition, improved binding effciency and selectivity. In this paper, we reported a straightforward approach to the synthesis of interpolyelectrolytes by co-assembling of the thiacalix[4]arene with four negatively charged functional groups on the one side of macrocycle, and pillar[5]arene with 10 ammonium groups located on both sides. Nanostructured polyelectrolyte complexes show effective packaging of high-molecular DNA from calf thymus. The interaction of co-interpolyelectrolytes with the DNA is completely different from the interaction of the pillar[5]arene with the DNA. Two different complexes with DNA, i.e., micelleplex- and polyplex-type, were formed. The DNA in both cases preserved its secondary structure in native B form without distorting helicity. The presented approach provides important advantage for the design of effective biomolecular gene delivery systems