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The aim of this paper was to evaluate the influence of anthropogenic pollution on the water quality of the Ciemięga River, which flows through the Jastków commune, located in the Lublin Province in the South-Eastern Poland. The analyses of the river water were conducted in the years 2019–2020. Each year, the samples for physicochemical analyses were collected seasonally (in February, May, August and November) from the seven selected Ciemięga River sampling points found in the following localities: Ożarów, Moszenki, Sieprawice, Jastków, Snopków and Jakubowice Konińskie. In addition, 3 series of microbiological analysis were conducted in 2020. Electrolytic conductivity, total phosphorus, nitrate-nitrogen and sulfates constituted the physicochemical indicators of poor water quality in the river. Their average values exceeded the standards for the 2nd class of water quality. High concentration of these indicators, especially of the total phosphorus, could have been related to the influx of domestic wastewater from agricultural holdings, wastewater flows from agricultural areas as well as soil erosion and leaching. The levels of E. coli bacteria and fecal coliform allocated the Ciemięga River waters to the 4th class of water quality and could result from domestic wastewater flow to the river. In order to improve the water quality of the Ciemięga River, it is necessary to reduce or eliminate point and non-point sources of pollution by means of streamlining of the agricultural areas fertilization, regulating the water and wastewater management, regulating of the waste management, as well as the appropriate spatial policy and landscaping of the water catchment areas. [ABSTRACT FROM AUTHOR]

Background: There exists few scientific reports on the quality of digitally reproduced dental arches, even though digital devices have been used in dentistry for many years. This study assesses the accuracy of the standard dental arch model reproduction using both traditional and digital methods. Methods: The quality of the full upper dental arch standard model reproduction by physical models obtained through traditional and digital methods was compared: gypsum models (SGM) and models printed from data obtained using an intraoral scanner (TPM) (n = 20). All models were scanned with a reference scanner. Comparisons were made using Geomagic Control X program by measuring deviations of the models relative to the standard model and analyzing linear dimensions deviations. Results: The average error of reproduction accuracy of the standard model ranged from 0.0424 ± 0.0102 millimeters (mm) (SGM) to 0.1059 ± 0.0041 mm (TPM). In digital methods, all analyzed linear dimensions were shortened to a statistically significantly degree compared to traditional. The SGM method provided the smallest deviations to a significant degree of linear dimensions from the pattern, and TPM the largest. The intercanine dimension was reproduced with the lowest accuracy, and the intermolar the highest in each method. Conclusions: Traditional methods provided the highest reproduction trueness of the full dental arch and all analyzed linear dimensions. The intercanine dimension was reproduced with the lowest accuracy, and the intermolar the highest in each method, where digital methods shortened all analyzed linear dimensions. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the concentration of salinity indicators in the Bystrzyca River in the city of Lublin, located in south-eastern Poland. The studies on the quality of water from the river were carried out from November 2018 to June 2019, i.e. in winter and spring. The water samples for analysis were taken from 9 measurement points located on the river under bridges and at high traffic roads. In total, 8 series of analyses were carried out, during which 72 water samples from the Bystrzyca River were examined. The samples were analyzed in terms of: water temperature, pH value, conductivity as well as concentration of chlorides and sulfates. An increase in both the specific conductivity and chloride and sulfate concentrations was found in the water from the Bystrzyca River during the period of low air temperatures (≤0o C), i.e. in December 2018 and January 2019. This may be a result of winter road maintenance procedures, i.e. by using salts for their defrosting. At the same time, an increase in the conductivity value and the concentration of chlorides and sulfates was observed with the course of the river, which indicates that the pollution generated in the city of Lublin has a negative impact on the water quality in the studied river. The salinity of the Bystrzyca River was greatly affected by the operation of the municipal wastewater treatment plant in Hajdów, especially by the use of coagulants: polyglycol chloride (PAX 18) and iron sulfate (PIX 113). [ABSTRACT FROM AUTHOR]