Author: Bc. Barbora Kuhnová Title: Maintaining physical fitness and adherence to physical activity in healthy elderly women. Objective: The main goal of the thesis is to find out whether or not the seniors that participated in the project EXODYA back in 2017 and 2018, managed to maintain the level of physical fitness and adherence to physical aktivity (PA). The secondary goal was to determine the level of current PA and also how the level of PA was affected by the Covid-19 pandemic. Method: This is an empirical-theoretical study with a qualitative-quantitative research design. The research group I (N=30, average age 72 ± 4,02 years) took part in a questionnaire survey that included the International Physical Activity Questionnaire IPAQ and supplementary questions about influencing PA by the pandemics, using Google form. The research group II was made by 7 women that were also part of the research group I and that took part in the EXODYA project in 2018. The testing of these women consisted of 4 items of the Senior Fitness Test, hand grip strength using a digital hand dynamometer and maximum oxygen demand based on a stress test on a bicycle ergometer. Results: Most of the senior women who participated in the EXODYA project in 2018 maintained a level of physical fitness as well as adherence to PA....

Industrial operations produce a notable amount of wastewaters with high concentration of chemical oxygen demand (COD), mostly consisting of organic carbon compounds. The treatment performance of electrochemical methods for organic removal and the effects of process parameters are the subject of this research. Three research tasks were performed. The first task was the removal of organic pollutants from three different industrial wastewaters using two different electrochemical methods; combined electrocoagulation + electrooxidation (EC+EO) and b) electrochemical peroxidation (ECP). Using only EC process was found to be significantly successful in removing suspended and colloidal pollutants and could remove more than 90% COD and 80% of TOC. The study showed that combined EC+EO process had better removal capability compared to ECP when operated under similar process conditions. The second task was to study the effect of the process parameters; pH, H2O2 dosage, current density, and operation time; and to optimize and estimate the best treatment conditions for the methods using Box-Behnken Design (BBD). For sugar beet wastewater, the results showed that EO could remove 75% of organics at optimum conditions of pH 5.3; current density of 48.5 mA/cm2; and operation time of 393 min. The canola oil refinery wastewater achieved more than 90% pollutant removal when the conditions were optimized at pH 5.8 – 6 with applied current density of 9.2 mA cm-2¬ run for nearly 300 min. The rate of degradation of the wastewater derived organic pollutants followed a first order kinetics for all the wastewaters investigated and the models were validated for goodness of fit with high R2. The final task was to compare treatment efficiency between the electrochemical processes. Based on the energy consumed and the performance efficiency to remove COD, sCOD, TOC and DOC in the three different wastewaters studied, EC+EO process was found suitable for the treatment of canola and sunflower oil wastewater. On the other hand, from the model prediction and the experiments conducted, EO resulted in better removal capability compared to ECP. Also, the consumption of energy by ECP was comparatively higher than EO process while taking longer time of operation for significant removal. / North Dakota Water Resources Research Institute; North Dakota Agricultural Experimental Station; Frank Bain Agricultural Scholarship

Water scarcity has become a global problem due to diminishing water resource and pollution of the remaining resources. The problems arising fromwater scarcity are exacerbated rapid urbanisation and industrialisation. Water quality management systems are introduced. Numerous water management methods exist some of which, if applied e ectively, can remedy these problems. In South Africa, water management systems are urgently needed to start addressing issues around the longterm sustainability of our limited water resource. Water quality modelling is one of the tools employed to assist in validating decisions made during the planning phase of a water quality management system. It also provides a means of exploring viable options to be considered when these decisions are to be made. A range of management options exist and implementing all of them may prove costly, therefore optimisation techniques are utilised to narrow down options to the most e ective and least costly among the available choices. Commonly, water quality models are used to predict concentrations in the river from which constraint equations are generated. The constraint equations are used in optimisation models to generate feasible solutions by either maximising or minimising the objective function. In this case the objective function is wastewater treatment cost. Constraints equations are based on the set in-stream water quality standard at selected theoretical measuring stations (checkpoints) in the stream and a feasible solution is one that suggests a treatment method that will ensure water quality standards are met at the lowest regional treatment cost. This study focused on the Upper Olifants river catchment near Witbank in Mpumalanga province. This catchment is subjected to extensive wastewater e uents from various mining operations and wastewater treatment plants. The aim here was to develop a water quality model for predicting dissolved oxygen (DO) concentration in the river, and to use a modelling approach to generate constraint equations for the system. A Streeter-Phelps stream simulation model was employed to predict DO concentration in the river. A mixed-integer programming technique was then used to evaluate the impact of nine wastewater treatment facilities discharging e uent into the river. Treatment levels were varied to test model reliability. The coupled stream simulation and optimisation model produced feasible solutions under 2 minutes, with each solution suggesting a range of treatment levels which ensured that the critical DO concentration was above 5 mg/L and the most stringent DO concentration the system could manage without violations anywhere else in the stream was obtained to be 7mg/L. / Dissertation (MEng)--University of Pretoria, 2013. / gm2014 / Chemical Engineering / unrestricted

Coal gasification stripped gas liquor (CGSGL) wastewater contains large quantities of complex organic and inorganic pollutants which include phenols, ammonia, hydantoins, furans, indoles, pyridines, phthalates and other monocyclic and polycyclic nitrogen-containing aromatics, as well as oxygen- and sulphur-containing heterocyclic compounds. The performance of most conventional aerobic systems for CGSGL wastewater is inadequate in reducing pollutants contributing to chemical oxygen demand (COD), phenols and ammonia due to the presence of toxic and inhibitory organic compounds. There is an ever-increasing scarcity of freshwater in South Africa, thus reclamation of wastewater for recycling is growing rapidly and the demand for higher effluent quality before being discharged or reused is also increasing. The selection of hybrid fixed-film bioreactor (HFFBR) systems in the detoxification of a complex mixture of compounds such as those found in CGSGL has not been investigated. Thus, the objective of this study was to investigate the detoxification of the CGSGL in a H-FFBR bioaugmented with a mixed-culture inoculum containing Pseudomonas putida, Pseudomonas plecoglossicida, Rhodococcus erythropolis, Rhodococcus qingshengii, Enterobacter cloacae, Enterobacter asburiae strains of bacteria, as well as the seaweed (Silvetia siliquosa) and diatoms. The results indicated a 45% and 79% reduction in COD and phenols, respectively, without bioaugmentation. The reduction in COD increased by 8% with inoculum PA1, 13% with inoculum PA2 and 7% with inoculum PA3. Inoculum PA1 was a blend of Pseudomonas, Enterobacter and Rhodococcus strains, inoculum PA2 was a blend of Pseudomonas putida iistrains and inoculum PA3 was a blend of Pseudomonas putida and Pseudomonas plecoglossicida strains. The results also indicated that a 70% carrier fill formed a dense biofilm, a 50% carrier fill formed a rippling biofilm and a 30% carrier fill formed a porous biofilm. The autotrophic nitrifying bacteria were out-competed by the heterotrophic bacteria of the genera Thauera, Pseudaminobacter, Pseudomonas and Diaphorobacter. Metagenomic sequencing data also indicated significant dissimilarities between the biofilm, suspended biomass, effluent and feed microbial populations. A large population (20% to 30%) of unclassified bacteria were also present, indicating the presence of novel bacteria that may play an important role in the treatment of the CGSGL wastewater. The artificial neural network (ANN) model developed in this study is a novel virtual tool for the prediction of COD and phenol removal from CGSGL wastewater treated in a bioaugmented H-FFBR. Knowledge extraction from the trained ANN model showed that significant nonlinearities exist between the H-FFBR operational parameters and the removal of COD and phenol. The predictive model thus increases knowledge of the process inputs and outputs and thus facilitates process control and optimisation to meet more stringent effluent discharge requirements. / Thesis (PhD)--University of Pretoria, 2017. / Chemical Engineering / PhD / Unrestricted

Sewage, agricultural runoff, and atmospheric deposition have greatly increased the amount of nutrients (largely nitrogen (N) and phosphorus (P)) in surface water nationwide. Excess nutrients are associated with algal blooms and dissolved oxygen depletion in many water bodies, but linkages between nutrients and dissolved oxygen have been largely correlative. Biochemical oxygen demand (BOD) is a regulated water quality parameter that is aimed at describing the amount of oxygen consumed during the decomposition of organic matter. Despite the awareness that excess nutrients are linked to dissolved oxygen in rivers, few studies in the nutrient criteria literature discuss BOD measurements or how nutrients may impact BOD. Accordingly, I used factorial experiments to test the effect of inorganic nutrients (as N, P and N+P) and dissolved organic carbon on BOD measurements in Utah streams. The study was carried out from January through summer baseflow in 2011, allowing me to evaluate the effects of spatial and temporal variation of ambient nutrient concentration on oxygen demand. The study design included measurements in streams above and below nutrient point-sources (publicly owned treatment works) and several reference sites. I used classification and regression trees to identify thresholds of TN and TP that separate BOD response to nutrients into statistically distinct groups. My results show that seasonal variation affected BOD levels. As temperatures rose and water levels increased during peak runoff, I observed the highest BOD response to nutrient additions. I also found a significant correlation between BOD and ambient nutrient concentrations during that time period. I identified potential nutrient-related thresholds that could be used to assign numeric criteria that would protect designated uses. The threshold values I found for TN and TP were 0.56 mg/L and 0.09 mg/L, respectively. My results suggest that BOD may be sensitive to nutrient inputs and my experimental approach could be used as one line of evidence to support nutrient criteria related to aquatic life uses.

Dissolved oxygen (DO) depletion in a water body is governed by two primary mechanisms: biological oxygen demand (BOD) from the water column, and sediment oxygen demand (SOD) from sediments. SOD is the dominant oxygen sink in many water bodies; measurements show as much as 95% of oxygen consumption as attributable to SOD (Truax, Shindala, & Sartain, 1996). Measuring SOD in surface water impoundments is an essential component in evaluating and an important input for modeling the health of a water body. Traditional SOD measurement methods are difficult in deeper waters, such as in reservoirs or lakes, because traditional SOD measurement chambers require direct placement. The goal of this research was to modify an existing SOD chamber design to support deployment and recovery in depths in excess of 5ft, typically from a boat or other floating platform. The design required accurate DO measurements, taken unattended and recorded for several hours to several days, for SOD calculations and other parameters such as cation releases under anaerobic conditions. Using a previously designed chamber, I developed tools and methods to meet these requirements. DO data logger probes were purchased so that DO calculations could be taken without the need of surface support. To mount the chambers inside the previously designed chambers, a new mounting mechanism was designed and installed onto the chamber lids. Deployment and recovery methods and design were developed to ensure the chambers would be recoverable from a boat in deep waters. Previously, the unmodified chambers could not be deployed unattended because of the required power and data link with the surface. Here I present an easily replicated chamber design that allows for remote chamber placement and measurement of SOD in deep waters without the need of SCUBA or other specialized equipment that is traditionally required. The chamber design allows water to circulate through the chambers until they are placed and closed on the sediment bed, at which time the measurements start, ensuring correct initial conditions. During deployment, the data logger will log DO concentrations at predetermined intervals for several hours or days at a time. To recover the chambers, the researcher must only find the buoy attached to the rope and hoist the units back to the surface. Modifications and methods were tested and revised over the course of several months and dozens of tests. Experiments were conducted at various depths, ranging from 12–50ft, which showed the versatility of the chambers. Using this design, other researchers will be able to generate substantial amounts of SOD data at depths that will allow accurate SOD behavior to be included in models of water impoundments.

No description available.

The purpose of this study was to characterize the leachate from a landfill in Pennsylvania that had been pretreated by activated sludge and propose the most efficient treatment for this effluent. These samples had been pretreated in a sequencing batch reactor that also was operated to remove nitrogen by nitrification/denitrification. The SBR samples were found to have low BOD, high COD, high TOC and a very low BOD/COD ratio. These SBR decant samples have poor UV transmittance and hence quench UV light. Five treatment methods were evaluated, coagulation, ultrafiltration, combined coagulation/ultrafiltration, combined ultrafiltration/oxidation and combined filtration/fentons. These processes were tested for their ability to remove BOD and TOC and also to evaluate the improvement in UV transmittance. It was found that coagulation; Ultrafiltration and Ultrafiltration combined with coagulation do not work in improving the transmittance properties though there is a significant BOD and TOC removal with these processes. Ultrafiltration combined with oxidation was found to work the best in terms of TOC removal. In this study, four oxidants, KMnO?, H?O?, NaOCl and Fenton's reagent were used. It was observed that Fenton's reagent was capable of removing 90% TOC at a dose of 1g/L each of iron salt and hydrogen peroxide at a pH of 4.5. Since Fentons reagent was found to be the most effective method, hence, efforts were made to optimize the oxidation process with Fenton's. The two parameters which were studied were the initial pH and the chemical dosage. The initial pH was varied from a value of 2.5 to 6.5. The range of iron salt and peroxide dose used was from 0.05 to 0.1 g/L. Additional studies were conducted using samples filtered through a 0.45 um filter and oxidized with Fenton's reagent. The Fenton's process for oxidation of filtrates from the 0.45?m filter was also optimized with respect to pH and chemical dosage to determine the most economical operating conditions. The maximum transmittance of 57% was obtained for an iron dose of 0.075 g/L and a peroxide dose of 0.075 g/L at a pH of 4.5. This is in comparison to the transmittance of unoxidized 1K ultrafiltrate which was found to be 21.5%. There was a significant difference in the performance of 1K and 0.45um filtrates in terms of TOC removal and percentage transmittance. The oxidation process for improving the UV transmittance of leachate can therefore be economically optimized depending upon the desired efficiency by varying the operational parameters. / Master of Science

The object or this experiment was to determine if and to what extent the B.O.D. of S.N.W. waste could be reduced by Heat Hydrolysis. This process gave B.O.D. reduction up to 80 percent when used on sulfite waste at Oregon State College and it was hoped that similar results could be obtained using S.N.W. liquor. The exper1mental part of the investigation was conducted to determine (1) it the B.O.D. content of S.N.W. liquor could be reduced by Heat Hydrolysis; (2) if pH, dilution and the addition of oxygen were factors that affected the reduction of B.O.D. These factors were determined by adjusting the raw liquor to the desired concentration and cooking the liquor in a closed container until certain conditions were obtained, namely, that of constant pressure with constant temperature. Ana1ysis of the raw and cooked liquor consisted of determining pH, total solids, and B.O.D., while analysis of the gas created during the cook was limited to the total amount of gas created and the amount of CO₂, CO, O₂ and H₂S in the gas. Four different series of cooks were conducted on each sample. They were, Neutral (raw liquor), Acid (raw liquor pH adjusted, Neutral-Oxygen added (raw liquor with oxygen added) and Ac1d-0xygen added (raw liquor pH adjusted with oxygen added). The samples used were 7OO ml., 465 ml., dilution 1:1 (232 ml. liquor plus 232 ml. distilled water) and dilution 2:1 (310 ml. distilled water plus 155 ml. liquor. / Master of Science

Dissolved oxygen at four times normal saturation inhibited growth and metabolism of summer planktobacteria in surface waters of alpine oligotrophic Mountain Lake (Giles County, Virginia). Data included viable colony counts, D-[U-¹⁴C]glucose incorporation into extractable lipid of colonies, and respiration-assimilation of D-[U-¹⁴C]glucose by lake water samples. Significant (P<0.05) differences were not detected in either colony counts or ¹⁴C-lipid when superoxide dismutase (30 U ml⁻¹) or catalase (130 U ml⁻¹) were added to the medium. The upper waters of Lake Hoare, Antarctica, contain dissolved oxygen at ≥42 mg liter⁻¹ (=HDO). HDO did inhibit D-[U-¹⁴C]glucose assimilation-respiration compared with normal atmospheric dissolved oxygen (=ADO) in Lake Hoare water. D-[U-¹⁴C]glucose was assimilated and respired optimally at 12°C in Lake Hoare. Colony formation was inhibited in both lakes. Colonies represented <1% of the fluorochrome-stained direct counts in Lake Hoare. Lake Hoare planktobacteria were smaller than the planktobacteria in Mountain Lake. ATP size fractionation revealed that 39% of ATP biomass was <0.5 Hm in Lake Hoare. Five microbial isolates were selected from Lake Hoare by growth under very high oxygen (=VHO, 4.6x in situ HDO, 55 lb in⁻² of added oxygen). One isolate was selected under ADO from shallow benthic mat underlying HDO waters. Isolates were examined for physiological characteristics which might enhance their survival in the HDO environment. While HDO incubation produced <36% of ADO incubated CFU, VHO was more selective producing <1%. Bacterial isolates were motile Gram negative rods, catalase and oxidase positive, differing in their growth response to temperature and nutrient concentration. One VHO isolate was a yeast. HDO reduced the maximal cell density in three isolates tested at higher nutrient concentrations, however, all three exhibited less repression as nutrients were lowered from 1000-10 mg liter⁻¹ in comparison to ADO grown controls. One isolate actually produced a cell density 3x that of the ADO control. Four of five bacterial isolates demonstrated HDO inducible superoxide dismutase (SOD). The inducible and constitutive SOD were the manganese type and had the same electrophoretic mobilities in respective isolates. All VHO isolates contained carotenoids. Pigmentation of the bacterial isolates differed due to the types and relative proportions of the constituent carotenoids. A carotenoid-negative mutant of one isolate grown under HDO exhibited a lengthened lag phase, decreased growth rate, maximal cell density and thereafter increased lysis compared to the same ADO grown strain and the carotenoid containing parent strain. The mutant and parent strain produced catalase and indistinguishable specific activities of SOD. Microorganisms in the high oxygen Lake Hoare waters may be protected from oxygen toxicity by the lake’s oligotrophic nature as well as a combination of cellular defenses. / Ph. D.