DERMATOLOGIC GELS SPREADABILITY MEASURING METHODS COMPARATIVE STUDY

Objective: The main objective of our study is the comprehensive analysis and characterization of the existing spreadability evaluation strategies, the comparison of the obtained results reproducibility and convergence through the example of the 9 most widely used dermatological gels. Methods: Dolobene®, Flucinar®, Ketorol®, Contractubex®, Dr. Theiss Venen gel®, Solcoseryl®, Deep Relief®, Hepatrombin® pharmacopoeia gel samples were analyzed using parallel-plate, “slip and drag”, and viscometry methods. Analysis was performed in flow mode at 32±0.2 °C, over shear rates ranging from 0 to 350 s−1, increasing over a period of 120 s, and was maintained at the superior limit for 10 s and then decreased during the same period. At least 5 replicates of each sample were evaluated, and the upward flow curves were fitted using the Casson mathematical model. Results: Solcoseryl® and Dolobene® showed the best spreadability in the parallel-plate method (3115.66±50.00 and 3316.63±50.00, respectively); Contractubex® and Dolobene showed the best spreadability in the “slip and drag” test (73.46±0.5 and 18.32±0.5, respectively); Solcoseryl® and Contractubex® showed the best spreadability in the viscometry test (43.86±0.5 and 76.92±0.5, respectively). Conclusion: This study analyzed the existing methods for determining the spreadability using commercially available samples of the dermatological gels as examples. The viscometric and the "Slip and drag" methods use different characteristics of spreadability, giving a complex evaluation of the measured parameter in vitro. Therefore, the combination of these two methods has the greatest prospects for reliable determination of this indicator.

Mass Transfer Characteristics of Haemofiltration Modules—Experiments and Modeling

Reliable mathematical models are important tools for design/optimization of haemo-filtration modules. For a specific module, such a model requires knowledge of fluid- mechanical and mass transfer parameters, which have to be determined through experimental data representative of the usual countercurrent operation. Attempting to determine all these parameters, through measured/external flow-rates and pressures, combined with the inherent inaccuracies of pressure measurements, creates an ill-posed problem (as recently shown). The novel systematic methodology followed herein, demonstrated for Newtonian fluids, involves specially designed experiments, allowing first the independent reliable determination of fluid-mechanical parameters. In this paper, the method is further developed, to determine the complete mass transfer module-characteristics; i.e., the mass transfer problem is modelled/solved, employing the already fully-described flow field. Furthermore, the model is validated using new/detailed experimental data on concentration profiles of a typical solute (urea) in counter-current flow. A single intrinsic-parameter value (i.e., the unknown effective solute-diffusivity in the membrane) satisfactorily fits all data. Significant insights are also obtained regarding the relative contributions of convective and diffusive mass-transfer. This study completes the method for reliable module simulation in Newtonian-liquid flow and provides the basis for extension to plasma/blood haemofiltration, where account should be also taken of oncotic-pressure and membrane-fouling effects.

Rapid Determination of the ‘Legal Highs’ 4-MMC and 4-MEC by Spectroelectrochemistry: Simultaneous Cyclic Voltammetry and In Situ Surface-Enhanced Raman Spectroscopy

The synthetic cathinones mephedrone (4-MMC) and 4-methylethcathinone (4-MEC) are two designer drugs that represent the rise and fall effect of this drug category within the stimulants market and are still available in several countries around the world. As a result, the qualitative and quantitative determination of ‘legal highs’, and their mixtures, are of great interest. This work explores for the first time the spectroelectrochemical response of these substances by coupling cyclic voltammetry (CV) with Raman spectroscopy in a portable instrument. It was found that the stimulants exhibit a voltammetric response on a gold screen-printed electrode while the surface is simultaneously electro-activated to achieve a periodic surface-enhanced Raman spectroscopy (SERS) substrate with high reproducibility. The proposed method enables a rapid and reliable determination in which both substances can be selectively analyzed through the oxidation waves of the molecules and the characteristic bands of the electrochemical SERS (EC-SERS) spectra. The feasibility and applicability of the method were assessed in simulated seized drug samples and spiked synthetic urine. This time-resolved spectroelectrochemical technique provides a cost-effective and user-friendly tool for onsite screening of synthetic stimulants in matrices with low concentration analytes for forensic applications.

Determination of rational values of the parameters of the container depot

Today, due to the increase in rail freight traffic, there is a shortage of containers, and the issue of shortage of containers has not been resolved for a long time. This substantiates the practical relevance of the study of container depots in railway transport. Another task is the development of mathematical models of the interconnection of the parameters of the container depot. Currently, there are several different methods and methods for calculating and determining the parameters of container sites, the analysis of which is given in the article. However, there is a need to supplement, clarify and unify the existing methods for calculating all kinds of parameters for a container depot, which justifies the theoretical relevance of the study. Connections with which the purpose of the article is to develop a methodology for the reliable determination of the most rational values of the parameters of the container terminal, thereby improving and increasing the level of customer service in transport in general. Research methods are based on a systematic analysis and generalization of existing methods and methods for calculating the capacity of container depots. The results of the study are presented by the developed methodology for determining the capacity of warehouses on railway transport, which provides a more qualified calculation and selection of container depot parameters, as well as a decrease in erroneous design decisions and an increase in the reliability of projects for the development and improvement of railway transport and the transport network as a whole.

Chirality and accurate structure models by exploiting dynamical effects in continuous-rotation 3D ED data

Dynamical diffraction effects are usually considered a nuisance for structure analysis from continuous-rotation 3D electron diffraction (3D ED) data like cRED and MicroED. Here we demonstrate that by accounting for these effects during the structure refinement, significantly improved models can be obtained in terms of accuracy and reliability with up to four-fold reduction of the noise level in difference Fourier maps in comparison to the standard structure determination routines that ignore dynamical diffraction. As dynamical diffraction effects break the inversion symmetry of the diffraction, they allow a quick, easy, and reliable determination of the absolute structure of chiral crystals.

Regional Government Revenue Forecasting: Risk Factors of Investment Financing

Accurate revenue prediction is a key factor for the reliable determination of the investment part of entire regional and local budgets, particularly during economic downturns and fiscal uncertainty. An unexpected decline in revenue requires the reduction in capital expenditures and forces the regional government to find additional sources to close the budget gaps. Current studies indicate that budget forecasts often underpredict revenue and use the available information inefficiently. In this article, the authors examine chosen methods of forecasting regional government revenue. In addition to classical forecasting models based on time series and causal models, an original structural forecasting procedure was proposed, which is effective especially in case of data delay. The reliability of applied methods was assessed using data from the Polish area of Zachodniopomorskie over the period 2000–2018. The found evidence supported results that were obtained by many other researchers, which indicated that less comprehensive methods of forecasting can provide reasonably accurate estimates.

ZnO Tips Dotted with Au Nanoparticles—Advanced SERS Determination of Trace Nicotine

Long-term exposure to nicotine causes a variety of human diseases, such as lung damage/adenocarcinoma, nausea and vomiting, headache, incontinence and heart failure. In this work, as a surface-enhanced Raman scattering (SERS) substrate, zinc oxide (ZnO) tips decorated with gold nanoparticles (AuNPs) are fabricated and designated as ZnO/Au. Taking advantage of the synergistic effect of a ZnO semiconductor with morphology of tips and AuNPs, the ZnO/Au-based SERS assay for nicotine demonstrates high sensitivity and the limit of detection 8.9 × 10−12 mol/L is reached, as well as the corresponding linear dynamic detection range of 10−10–10−6 mol/L. Additionally, the signal reproducibility offered by the SERS substrate could realize the reliable determination of trace nicotine in saliva.

wells of gas and gas condensate reservoirs in the South-Eastern part of the Bukhara-Khiva region and methods for increasing their productivity

The article examines the methods of increasing the productivity of wells of gas and gas condensate reservoirs in the south-eastern part of the Bukhara-Khiva region (BHR). The role of gas calculation methods in determining the gas reserve of Mesopotamia in sveza with an increase in the share of gas reserves from 1 to 10 million tons of conventional fuel is shown. Certain difficulties have been identified in the issue of reliable determination of gas reserves in the limited fund of wells and large ranges of changes in calculated parameters. The determining significance of the value of gas reserves in calculating the forecast indicators of the development and technologies of their extraction is justified. It is established that increasing the degree of reliability of calculating gas reserves ensures the efficiency of its extraction, as well as the rational use of material and technical resources and financial capabilities of the enterprise. The advantages of such methods for determining gas reserves as the volume method, the material balance method, and static models are disclosed. A specific description of each of these methods and their application for calculating gas reserves at the Northern Guzar field is given.

The intraoral permeability measurement as a screening for artifact formation by orthodontic products in MRI

Aim Metal dental products lack precautionary statements regarding MR compatibility due to an exemption in the labelling obligation. Hence, it is difficult for radiologists to decide whether to remove fixed metal objects in patients prior to MRI. A solution could be the direct determination of the magnetic permeability (µr) as a decisive material-related predictor of artifact formation and other interactions. Thus, the applicability of an industrially used measurement device as a screening instrument and the relevance of the manufacturer’s application restrictions in vitro and in vivo were tested. Methods Precision and trueness were tested using self-made test objects with different dimensions and different permeability. To clarify whether the measurement results are affected by the remanence (BR) induced in the objects, 28 brackets of different materials were exposed to a weak and a strong external magnetic field and the magnetic flux density before and after these exposures was compared. The clinical test was performed on a volunteer with an orthodontic appliance experimentally composed of brackets with different levels of magnetic permeability (µr). Validity and intra- and interrater reliability were calculated using two rater groups consisting of four dentists and four medical-technical radiology assistants (MTRA), respectively. Results With coefficients of variation below 0.14%, precision was excellent regardless of object surface and size. Trueness was high on objects with µr ≤ 1.002, and decreased with increasing µr, for which size-dependent correction factors were calculated. Intra- and interrater reliability and validity were excellent and independent of professional intraoral manipulation experience. Conclusions The permeability measurement allows for a valid and reliable determination of the magnetizability of intraoral metal objects. When used as a screening tool to detect nonartifact-causing objects, no correction factor needs to be calculated. For the first time, it offers radiologists a decision support for the selective removal of only the highly permeable components of the multiband apparatus.