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  • Author: Barbara Tomaszewska x
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Abstract

The anthropological analysis and assessment of the living conditions of historical populations should be comprehensive. Due to the scarcity of the well-preserved skeletal remains of a population buried at the cemetery in Wyszyński Street, Wrocław, each piece of information is particularly important in providing the complementary information about living and health conditions of late medieval and early modern inhabitants of Wrocław. This study aims to assess the living conditions of the late medieval and early modern Wrocław inhabitants. This aim was reached by analyzing the frequency of non-metrical cranial and postcranial traits, physiological stress indicators, and pathological lesions. The importance of these traits for population studies is also discussed. For 98 skeletons (22.4% male and 37.8% female) from a cemetery located in Wyszyński Street, (15th –18th centuries AD), the frequencies (p) of the following traits were analyzed: 38 non-metric cranial and 9 post-cranial traits, the morphological indicators of physiological stress (i.e. cribra orbitalia and enamel hypoplasia), caries and pathological lesions on bones. Among the non-metric cranial traits, only nine (23.7%) were not observed. The most frequent (from p= 0.30 to p=0.65) were foramen parietale, incisura frontalis accesoria seu foramen frontale accesorius, foramen supraorbitale, M3 mandibulare, ossicula suturae lambdoideae, and foramen mastoideum extrasuturale. Only three non-metric post-cranial traits were observed, but with low frequency (p=0.01 and 0.02). Cribra orbitalia was present in 37.0% of the skeletons while enamel hypoplasia was present in only 2.6%. Susceptibility to caries occurred in 68% of the cases while carries lesions occurred in 31.2%. Among pathological changes, the most frequent were degenerative changes (21.6%) and injuries (19.6%). Owing to the poorly preserved remains, the complete assessment of the living conditions of the population was difficult. The number of the observed traits would have probably increased, had the number of complete and well-preserved skeletons been higher. The results of the study suggest that the living conditions of the studied population were poor. It is hypothesized that the cemetery was a burial place for prisoners and victims of various epidemics that affected the city. But since the historical sources of this cemetery are scarce, it is hard to unequivocally state its purpose with certainty.

Abstract

When identifying the conditions required for the sustainable and long-term exploitation of geothermal resources it is very important to assess the dynamics of processes linked to the formation, migration and deposition of particles in geothermal systems. Such particles often cause clogging and damage to the boreholes and source reservoirs. Solid particles: products of corrosion processes, secondary precipitation from geothermal water or particles from the rock formations holding the source reservoir, may settle in the surface installations and lead to clogging of the injection wells. The paper proposes a mathematical model for changes in the absorbance index and the water injection pressure required over time. This was determined from the operating conditions for a model system consisting of a doublet of geothermal wells (extraction and injection well) and using the water occurring in Liassic sandstone structures in the Polish Lowland. Calculations were based on real data and conditions found in the Skierniewice GT-2 source reservoir intake. The main product of secondary mineral precipitation is calcium carbonate in the form of aragonite and calcite. It has been demonstrated that clogging of the active zone causes a particularly high surge in injection pressure during the fi rst 24 hours of pumping. In subsequent hours, pressure increases are close to linear and gradually grow to a level of ~2.2 MPa after 120 hours. The absorbance index decreases at a particularly fast rate during the fi rst six hours (Figure 4). Over the period of time analysed, its value decreases from over 42 to approximately 18 m3/h/MPa after 120 hours from initiation of the injection. These estimated results have been confi rmed in practice by real-life investigation of an injection well. The absorbance index recorded during the hydrodynamic tests decreased to approximately 20 m3/h/MPa after 120 hours.

Abstract

In the literature there are no unequivocal assessments of the effect of paternal age on the risk of cerebral palsy (CP). The objective of the studies was the analysis of the influence of paternal age on this risk, considering all the important risk factors and division into singleton and twin, as well as term- and preterm-born infants. The inquiry included a group of 278 children with cerebral palsy from selected education-therapeutic institutions in Poland. The control group consisted of the data from medical records of 435 neonates born in God’s Mercy Hospital in Limanowa, Poland. The data were based on a questionnaire designed to obtain information which would make it possible to ascertain the probable etiological factors. Constructed models of logistic regression were used in statistical analysis. The results were presented as the odds ratio (OR) with 95% confidence interval (CI). Though the estimation with a complex model of logistic regression showed no significant effect of paternal age on the occurrence of cerebral palsy, it confirmed it as a stronger predictor compared to maternal age. Disregarding paternal of age while considering maternal age and other risk factors may lead to a bias in the estimations of the risk cerebral palsy.

Abstract

The Miechów Trough and the central part of the Carpathian Foredeep in southern Poland have a highly complex geological structure and numerous fault zones. These features play a significant role in hydrogeological conditions of the area. In this area drinking water, medicinal groundwater or thermal groundwater occur, so recognition of their circulations is basic for reasonable groundwater management. In this note, a hydrogeological conceptual model, created for the purpose of regional scale mathematical modelling, is presented. This conceptual model illustrates the geology of the hydrogeological system modelled, as well as hydrogeological conditions and characteristics of groundwater circulation, as determined by tectonics. Typical of the research area is the wide diversity of geological and hydrogeological conditions. The Busko-Zdrój area, a region with a long history of exploitation of medicinal groundwater, presents the best example.

Abstract

M embrane-based water desalination processes and hybrid technologies are often considered as a technologically and economically viable alternative for desalination of geothermal waters. This has been confirmed by the results of pilot studies concerning the UF-RO desalination of geothermal waters extracted from various geological structures in Poland. The assessment of the feasibility of implementing the water desalination process analysed on an industrial scale is largely dependent on the method and possibility of disposing or utilising the concentrate. The analyses conducted in this respect have demonstrated that it is possible to use the solution obtained as a balneological product owing to its elevated metasilicic acid, fluorides and iodides ions content. Due to environmental considerations, injecting the concentrate back into the formation is the preferable solution. The energy efficiency and economic analysis conducted demonstrated that the cost effectiveness of implementing the UF-RO process in a geothermal system on an industrial scale largely depends on the factors related to its operation, including without limitation the amount of geothermal water extracted, water salinity, the absorption parameters of the wells used to inject water back into the formation, the scale of problems related to the disposal of cooled water, local demand for drinking and household water, etc. The decrease in the pressure required to inject water into the formation as well as the reduction in the stream of the water injected are among the key cost-effectiveness factors. Ensuring favourable desalinated water sale terms (price/quantity) is also a very important consideration owing to the electrical power required to conduct the UF-RO process.

Abstract

A proper methodology for collecting samples of geothermal water makes it possible not only to determine the hydrochemical characteristics of the water, but also to assess its temporal and spatial variability. The knowledge about the concentration of selected elements as well as the values of field measurements can help to indicate their impact on other environments and the processes that occur in a geothermal system. An important issue is the quality of the results obtained from in-situ measurements of unstable parameters, i.a. pH and electrical conductivity (EC). The results of measurements presented in the paper were completed with the use of three different devices in hot and cooled raw geothermal water (field test). The research was performed during two seasons of increased (winter) and lower (summer) exploitation of geothermal water. The percentage difference between EC at temperatures of 22°C and 75°C was 3.27%; however, for the pH the observed percentage difference was only 0.26%. An additional experiment was carried out on a laboratory scale to indicate the influence of temperature changes on pH and EC measurements.

Abstract

Nowadays, numerical modelling is a common tool for supporting the research of geothermal systems. Due to the development of computer sciences and access to software dedicated to numerical modelling of hydrogeological processes this is possible. Research can schematise hydrogeological conditions and simulate the work of geothermal systems and thermal water intakes. Research creates numerical models of geothermal systems at the regional and local scale for simulating work of specific thermal waters for example.

In connection with the economic development of the use of thermal waters in Poland there are many research projects where numerical modelling occurs as a primary tool. This paper provides an overview of research issues where the solution to the problem was found by using computer applications and numerical simulators.

Abstract

There is often a need to improve the taste of mineral water by reducing the sulphate ion content. It was found that for such an effect, nanofiltration (NF) process can be used. In the case, the proposed formula was assumed obtaining a mineral water with reduction of H2S and SO4 2- content through the following processes: stripping - UF/MF or rapid fi ltration - nanofiltration - mixing with raw water or filtration through calcium bed. The paper shows the results of the tests, with use of mineral waters and nanofiltration. Commercial nanofiltration membranes NF-270 Dow Filmtec and NF-DK GE Infrastructure Water&Process Technologies were applied. NF was carried out for mixed water from both water intakes (1 and 2), recovery of 50%, at transmembrane pressure of 0.8-1.2 MPa in the dead-end fi ltration mode. In addition, the permeate obtained in NF was filtered through a column fi lled with 1.0-3.0 mm limestone rock, in order to improve the composition of mineral water. The tested mineral water is the sulphate-chloride-sodium-calcium-magnesium in nature and contains 991 mg/L of SO4 2- and 2398 mg/L of TDS, while the permeate after NF showed the chloride - sodium hydrogeochemical type (TDS: 780-1470 mg/L, sulfate 10-202.7 mg/L, calcium 23-39.7 mg/L, magnesium 11-28 mg/L). As a result of water treatment in the NF process, high reduction of SO4 2- ions was obtained (79-98.7%), while the TDS was reduced in 51-64%. Because the process of NF allows for relatively high reduction of bivalent ions, a significant reduction in calcium ion content (84-88%) and magnesium (84-89%) has been also obtained. Monovalent ions were reduced to a lesser extent, i.e. sodium in 46% and bicarbonates in 39-64.1%. Despite obtaining the positive effect of the sulphate ions content reduction, the NF process significantly changed the mineralogy composition of water. The permeate filtration (DK-NF membrane) on the CaCO3 deposit led to a correction of the hydrogeochemical type of water from chloridesodium to chloride-bicarbonate-sodium. The concentration of calcium ions was increased by 60.5% and was 28.2 mg/L, and bicarbonate ions by 7.78% (increased to 195 mg/L). Based on a morphological assessment of the deposits in the SEM image and their chemical composition, the presence of gypsum crystals was detected on the surface of the NF-270 membrane. The deposits formed on the NF-DK membrane were of a completely different character as aggregations of iron and aluminium oxides/hydroxides were found. Such significant mineralogical differences between the secondary deposits crystallising on the surface of the membranes point to the impact of several factors, including membrane characteristics, concentration polarisation, mass transport mechanisms, etc.

Abstract

The Chociwel region is part of the Szczecin Trough and constitutes the northeastern segment of the extended Szczecin-Gorzów Synclinorium. Lower Jurassic reservoirs of high permeability of up to 1145 mD can discharge geothermal waters with a rate exceeding 250 m3/h and temperatures reach over 90°C in the lowermost part of the reservoirs. These conditions provide an opportunity to generate electricity from heat accumulated in geothermal waters using binary ORC (Organic Rankine Cycle) systems. A numerical model of the natural state and exploitation conditions was created for the Chociwel area with the use of TOUGH2 geothermal simulator (i.e., integral finite-difference method). An analysis of geological and hydrogeothermal data indicates that the best conditions are found to the southeast of the town of Chociwel, where the bottom part of the reservoir reaches 3 km below ground. This would require drilling two new wells, namely one production and one injection. Simulated production with a flow rate of 275 m3/h, a temperature of 89°C at the wellhead, 30°C injection temperature and wells being 1.2 km separated from each other leads to a small temperature drop and moderate requirements for pumping power over a 50 years’ time span. The ORC binary system can produce at maximum 592.5 kW gross power with the R227ea found as the most suitable working fluid. Geothermal brine leaving the ORC system with a temperature c. 53°C can be used for other purposes, namely mushroom growing, balneology, swimming pools, soil warming, de-icing, fish farming and for heat pumps.

Abstract

The aim of this study was to define the effects of diet containing the same mineral content of mineral salt or amino acid chelate, and diet containing various levels of Cu amino acid chelate on liver histomorphometry in growing rats. Male Wistar rats were used in the 12th week experiment. The control group (n = 12) was fed standard diet, which provided Cu in an inorganic form at the level required for rats. The experimental animals were divided into four groups (each n = 12) depending on different levels (100%, 75%, 50%, 25% covered daily demand) of Cu supplementation in chelated form. Cu content was determined in the liver tissue and blood plasma. Immunohistochemical staining with caspase-3 antibody was performed. Microscopic assessment of the liver structure indicated that Cu supplementation did not change the liver architecture. However, histomorphometric analysis revealed a significant increase in the number of nuclei, total cell number, and multinucleated hepatocytes in rats supplemented with the organic form of Cu at the level of 25% compared with the control group. There was a considerable increase in the number of apoptotic cells and ballooning degeneration of hepatocytes, especially in groups supplemented with organic form of Cu covering the daily demand in 100% and 75%, in comparison to control group. Moreover, there was no Cu deposition in the liver and changes in Cu content in blood. Cu provided in the diet in organic form covering an amount of its minimum daily demand in 25% appears to be the least harmful with regard to the liver. It indicates that there is a need to establish the level of diet supplementation with Cu amino acid chelates.