Methods to improve the remediation of polycyclic aromatic hydrocarbons (pahs) in aerobic and anaerobic environments

Oil spills occur regularly in terrestrial environments and crude oil can contain many compounds that are highly resistant to degradation. Among these compounds are high levels of polycyclic aromatic hydrocarbons (PAHs) which are not only toxic but can also be carcinogenic and/or mutagenic. The first chapter of this dissertation includes an extensive review chapter on the variables affecting the anaerobic degradation of hydrocarbons, with a particular focus on PAHs. Electron acceptors, electron donors, temperature, salinity, pH all play key roles in determining the possibility effective of effective degradation occurring. Thus, by addressing solutions, such as biostimulation, improving environmental variables for optimal growth and enzymatic rates, and increasing the supply of the electron acceptors needed for anaerobic respiration help to remove obstacles to biodegradation. Additionally, the use of co-substrates or techniques such as bioaugmentation can further enhance this endeavor. Aerobic hydrocarbon degradation also has its challenges, especially for complex aromatic compounds such as PAH.s Electrokinetics (EK) is a remediation technology can be used to make species more accessible such as contaminants, nutrients, electrons acceptors, and electron donors. EK technology can be used to migrate certain contaminants but can also greatly enhance the aerobic degradation of PAHs primarily by increasing bioavailability and nutrient delivery. Studies were conducted to examine differences in electromigration rates for sand and clay. Two dyes, a red dye with anionic properties (FD&C 40) and a green dye with both anionic and cationic properties, composed of turmeric and Spirulina Blue were analyzed separately. The component of the green dye found to readily migrate is Spirulina Blue, consisting primarily of the protein pigment C-phycocyanin. The red dye in both sand and clay moves towards the anode, as predicted, and the rate between the two media was found to be approximately ten-fold. The green dye, having amphoteric qualities, can accept or donate protons, and can thus become strongly positively or negatively charged depending upon the pH of the system. It was found that due to a shifting pH gradient over time (in sand), this dye was initially anionic and thus migrated towards the anode but ceased migration after 48-72 hours due to a shift to a positive charge. Additional studies were conducted to observe how pH gradients in both sand and soil change over time. It is discovered that the rate at which the pH changes is dependent upon system variables including the current applied, which appears to absent from the literature, and that the initial semi-linear trend does not match the final gradient typically reported. The final study investigates the potential of EK technology to enhance biodegradation. In order to do so, a sandy soil, spiked with three compounds (fluorene, phenanthrene, fluoranthene) is placed within self-designed electrokinetic setups and an initial experiment shows a high possibility of PAH degradation but is unconfirmable. A second experiment attempts to verify the general findings of the first experiment and employs the use of a surfactant (Brij-35), which is thought to increase microbial movement throughout the contaminated soil and possibly reduce the sorption of PAHs to soil particles, both thereby increasing bioavailability and degradation rates. While biological activity is very apparent in this experiment, no degradation is observed and this may be due to a presence of carbonaceous materials (i.e. organic matter) within the soil. This yields an additional variable that must be taken into consideration in future in-situ studies or remediation projects. Overall it is found that many factors need to be taken into consideration for both aerobic and anaerobic biodegradation of PAHs. Increasing favorable growth conditions and increasing bioavailability can greatly help with this endeavor. Electrokinetics is an efficient means of ensuring this takes place but very specific designs or methods may be needed and pH gradients and extremes are found to provide significant obstacles to certain implementation but the results found in these experiments may be helpful to shed light on means of maintaining biological or chemical degradation experiments in an in-situ environment

Classical potential energy calculations for ApA, CpC, GpG, and UpU. The influence of the bases on RNA subunit conformations

Classical potential energy calculations have been made for the ribodinucleoside monophosphates ApA, CpC, GpG, and UpU. Van der Waal's, electrostatic, and torsional contributions to the energy were calculated, and the energy was minimized with the seven backbone conformational angles as simultaneously variable parameters. At the global minimum, ApA and CpC have conformations like double helical RNA: the angles ω′ and ω are g−g−, the sugar pucker is C3′-endo, and the bases are anti. GpG and UpU, on the other hand, have the ω′,ω angle pair g−t at the global minimum, and for GpG the bases are syn. Energy contour maps for ω′ and ω show two broad, low energy regions for ApA, CpC, and UpU: one is g−g−, and the second encompasses g−t and g+g+ within a single low energy contour. The two regions are connected by a path at 10–13 kcal./mole. For GpG, with bases syn, however, only a small low-energy region at g−t is found. The helical ‘A’ RNA conformation is 8.5 kcal/mole higher for this molecule. Thus, the base composition is shown to influence the conformations adopted by dinucleoside phosphates. Comparison of calculations with experimental data, where available, show good agreement

Standardizing data reporting in the research community to enhance the utility of open data for SARS-CoV-2 wastewater surveillance

SARS-CoV-2 RNA detection in wastewater is being rapidly developed and adopted as a public health monitoring tool worldwide. With wastewater surveillance programs being implemented across many different scales and by many different stakeholders, it is critical that data collected and shared are accompanied by an appropriate minimal amount of meta-information to enable meaningful interpretation and use of this new information source and intercomparison across datasets. While some databases are being developed for specific surveillance programs locally, regionally, nationally, and internationally, common globally-adopted data standards have not yet been established within the research community. Establishing such standards will require national and international consensus on what meta-information should accompany SARS-CoV-2 wastewater measurements. To establish a recommendation on minimum information to accompany reporting of SARS-CoV-2 occurrence in wastewater for the research community, the United States National Science Foundation (NSF) Research Coordination Network on Wastewater Surveillance for SARS-CoV-2 hosted a workshop in February 2021 with participants from academia, government agencies, private companies, wastewater utilities, public health laboratories, and research institutes. This report presents the primary two outcomes of the workshop: (i) a recommendation on the set of minimum meta-information that is needed to confidently interpret wastewater SARS-CoV-2 data, and (ii) insights from workshop discussions on how to improve standardization of data reporting

Anaerobic digestion of equine waste:

The goals of this project were to determine the methane production potential of horse manure during anaerobic digestion; to examine the effect of softwood chip bedding, pelleted Woody Pet® softwood bedding, and straw on the methane production potential of equine stall waste; and to investigate the feasibility of co-digestion of waste food and equine waste under thermophilic conditions. Initial results suggested that softwood bedding may have inhibited methane production in 15 L semi-continuous digesters. However, further extensive investigation in batch and continuous flow digesters determined that softwood bedding did not inhibit methane production and, on the contrary, contributed to methane production. The methane production potential for horse manure at 35°C averaged 139 ± 65 L/ kg VS (average ± standard deviation) and 29 ± 15 L/ kg wet weight, corresponding to 9.2 ± 4.8 x 105 kJ / metric ton wet weight. The energy production potential of stall waste with softwood chip bedding ranged from 4.0 ± 0.4 x 105 kJ / metric ton wet weight to 6.6 ± 0.8 x 105 kJ / metric ton wet weight, depending upon the relative amount of bedding present. Co-digestion of equine waste and food waste under thermophilic conditions was performed at the 20 L and 6.3 m3 scale. The 20 L thermophilic digesters were fed a variety of food wastes in addition to stall waste containing softwood bedding. The methane production from these digesters was 356 ± 61 L/kg VS-d. The large-scale (6.3 m3) digester was operated in excess of one year primarily on waste food and horse manure (no bedding). The loading rate increased over time to 1.7 kg VS/m3-d. The methane content of the biogas was 55.7 ± 5.2 %. Total ammonia nitrogen approached 5 g/L, suggesting a higher C:N ratio feed stock mixture than that afforded by the waste food and horse manure mixture might be necessary for future applications.M.S.Includes bibliographical references (p. 115-122)by Brian A. Wartel

Implementing wastewater surveillance for SARS-CoV-2 on a university campus: Lessons learned

Wastewater surveillance, also known as wastewater-based epidemiology (WBE), has been successfully used to detect SARS-CoV-2 and other viruses in sewage in many locations in the United States and globally. This includes implementation of the surveillance on college and university campuses. A two-phase study was conducted during the 2020–2021 academic year to test the feasibility of a WBE system on campus and to supplement the clinical COVID-19 testing performed for the student, staff, and faculty body. The primary objective during the Fall 2020 semester was to monitor a large portion of the on-campus population and to obtain an understanding of the spreading of the SARS-CoV-2 virus. The Spring 2021 objective was focused on selected residence halls and groups of residents on campus, as this was more efficient and relevant for an effective follow-up response. Logistical problems and planning oversights initially occurred but were corrected with improved communication and experience. Many lessons were learned, including effective mapping, site planning, communication, personnel organization, and equipment management, and obtained along the way, thereby paving an opportune guide for future planning efforts.https://doi.org/10.1002/wer.1080

Standardizing data reporting in the research community to enhance the utility of open data for SARS-CoV-2 wastewater surveillance

SARS-CoV-2 RNA detection in wastewater is being rapidly developed and adopted as a public health monitoring tool worldwide. With wastewater surveillance programs being implemented across many different scales and by many different stakeholders, it is critical that data collected and shared are accompanied by an appropriate minimal amount of meta-information to enable meaningful interpretation and use of this new information source and intercomparison across datasets. While some databases are being developed for specific surveillance programs locally, regionally, nationally, and internationally, common globally-adopted data standards have not yet been established within the research community. Establishing such standards will require national and international consensus on what meta-information should accompany SARS-CoV-2 wastewater measurements. To establish a recommendation on minimum information to accompany reporting of SARS-CoV-2 occurrence in wastewater for the research community, the United States National Science Foundation (NSF) Research Coordination Network on Wastewater Surveillance for SARS-CoV-2 hosted a workshop in February 2021 with participants from academia, government agencies, private companies, wastewater utilities, public health laboratories, and research institutes. This report presents the primary two outcomes of the workshop: (i) a recommendation on the set of minimum meta-information that is needed to confidently interpret wastewater SARS-CoV-2 data, and (ii) insights from workshop discussions on how to improve standardization of data reporting