Assessing the potential for tertiary nitrification in sub-surface flow constructed wetlands

The challenge of how to maintain or improve wastewater treatment performance without causing an excessive increase in energy or costs is increasingly focussed towards ammonia. On small sewage treatment works, solutions have historically been energy intensive: to divert waste to a larger plant, add a polishing step to the end of the process flow sheet or upgrade and replace upstream processes. Constructed wetlands (CWs) offer a low energy alternative to meet these challenges. This review explores oxygen transfer theory; nitrification performance of existing CW systems, and the key affecting factors to be considered when implementing the technology for tertiary treatment upgrades. Future perspectives include the use of artificial aeration and greater consideration of vertical sub-surface flow systems as they achieve the nitrification capacity in a smaller footprint than horizontal flow systems and, where suitable hydraulics permit, can be operated under very low energy demand

Performance of four full-scale artificially aerated horizontal flow constructed wetlands for domestic wastewater treatment

A comparison of the performance of four full-scale aerated horizontal flow constructed wetlands was conducted to determine the efficacy of the technology on sites receiving high and variable ammonia loading rates not yet reported in the literature. Performance was assessed in terms of ammonia and solids removal, hydraulic conductivity and mixing patterns. The capability of systems to produce ammonium effluent concentrations <3 mgNH4 + -N/L was observed across all sites in systems receiving variable loadings between 0.1 and 13.0 gNH4 + -N/m2 /d. Potential resilience issues were observed in relation to response to spike loadings posited to be due to an insufficient nitrifying population within the beds. Hydraulic conductivity and flow mixing patterns observed suggested deterioration of the reactor effective volume over time. Overall, the study demonstrates the efficacy of the technology where ammonium removal is required on small sites receiving high and variable flow rates, with adequate removal of organics and solids, but no significant benefit to the long term hydraulics of the system

MOCK FLOW LOOP (MFL) FOR SELF-POWERED FONTAN CIRCULATION

The Fontan procedure is the current treatment for babies born with Hypoplastic Left Heart Syndrome (HLHS). The surgery entails multiple severe complications and a survival rate of less than 50% by adulthood. Modification to the Fontan surgery is proposed to lower mortality rate in patients. A bifurcating graft (IJS) has been designed and validated via computational fluid dynamics (CFD) to increase velocity and reduce pressure within the pulmonary arteries. A dynamically scaled mock flow loop (MFL) will be configured to validate the optimized IJS results obtained from the CFD design. The MFL will be based on a reduced Fontan lumped-parameter model (LPM) and will be comprised of RLC components of the systemic and the pulmonary circuit. These RLC values are obtained from clinical references to approximate normal human physiology specific to each vessel bed. The Harvard Medical pulsatile pump provides the targeted flow rate through the IJS. Flow and pressure sensor data at critical points in the MFL are acquired via National Instruments multichannel data acquisition board and processed using LabView. A patient-specific 3D model of the Fontan junction (test section) will be produced via 3D printing (inferior and superior vena cavae attached to left and right pulmonary arteries)

An Experimental Verification of Computational Models Demonstrating Hip Reductions via Pavlik Harness in Developmental Dysplasia of the Hip

Developmental Dysplasia of the Hip (DDH) refers to an abnormal hip condition in neonates characterized by anomalous development of the hip joint – in which hip joint dislocation, misalignment, and musculoskeletal instability are present in newborn infants. In infants, the Pavlik Harness is the preferred standard orthopedic device used worldwide to non-surgically correct DDH in infants.We propose to use engineering fundamentals to determine the mechanics governing the operation of these devices in order to determine conclusive mechanisms of action for the device, and to devise case-specific methods to actively vector the femoral head to its proper concentric position in the acetabulum, thereby decreasing the incidence of disability due to the unsuccessful treatment of severe hip dysplasia. In order to experimentally verify the computational model of hip reduction and abduction via the Pavlik Harness in severe cases of DDH, a mechanical bench-top model of DDH dislocation will be designed, constructed, and implemented into the experiment. This bench-top design will include a readily interchangeable partition for patient-specific 3D-printed hip musculoskeletal hip structures, used to validate the patient-specific computational models obtained from computer models generated from CT and MRI scans obtained from patients used in previous research. The primary impact of this project on society will be to assist in the improvement of the success rate non-surgical interventions for patients with Developmental Dysplasia of the Hip, as well as its consequences in adulthood, as DDH is found to be responsible for 29% of primary hip replacements in people up to sixty (60) years of age

Embodied Ethos: Negotiations of Authority, Credibility, and Trust in Roman Republican Coinage and Renaissance Texts

“Embodied Ethos” explores how coins negotiate rhetors’ ethos in antiquity and how Renaissance texts illustrated with coin images reconstruct and appropriate the ethos of ancient coins. With a methodological framework that puts in conversation ancient rhetorical theories, modern theories in visual and material rhetoric, and cognitive linguistics, the project approaches ethos as an interweaving of authority, credibility, and trust, as well as a form of inter-subjectivity between rhetors and audiences. Applied to a discussion of early Greek and Roman coinage, this framework reveals that the negotiation of ethos occurs in relation to transcendental, social, or individual systems of power, truths, and values. An analysis of Roman Republican coins minted at the onset of the civil war between Caesar and Pompey suggests that the warrying factions use coin iconography and inscriptions to negotiate the leaders’ ethos and to mount responses to political crises. While Pompeian coinage invokes Rome’s past and elevates Pompey to transcendental status, Caesarean coinage invokes Rome’s future and encourages allegiance to Caesar as an individual. In the Renaissance, coin images import the ethos of ancient coins into printed texts. Guillaume Rouillé’s Promptuaire des medalles integrates coin images into literacy-based contexts and appropriates the ethos of ancient coins in order to energize the life of the text, to advance a form of literacy that balances oral and visual reading, and to help audiences negotiate their own ethos as readers. Madeleine de Scudéry’s Les Femmes illustres appropriates the ethos of ancient coins to support the ethos of women as marginalized rhetors. In this text, coin images invoke the public roles of famous women of antiquity, draw attention to the female orators as a community of speakers, and encourage audiences to accept and read a rhetorical text about women. Overall, the transmission of coin ethos from antiquity into the Renaissance suggests that, as objects of cultural significance, coins participate in complex networks of objects and texts and carry persuasive messages across cultures and time periods

Impact of aeration on macrophyte establishment in sub-surface constructed wetlands used for tertiary treatment of sewage

The effect of artificial aeration on plant growth in constructed wetlands in terms of above and below ground biomass and nutrient uptake of two macrophyte species Phragmites australis and Typha latifolia was carried out to provide quantitative, mechanistic evidence to support any differences between the plant species establishment. Pilot scale systems were built and supplied with different intensities of aeration and corresponding controls, with supporting evidence from two full scale operational sites. Results show T. latifolia was more impacted by aeration than P. australis when comparing against their respective non-aerated controls, evidenced in reduced height, growth rate and leaf length. However, the impact was less visible due to T. latifolia's faster growth rate compared to P. australis. Micro and macronutrient uptake by each species had no discernible pattern, preventing the identification of a definitive mechanism to explain the retarded growth. However, results suggest a synergy between iron and manganese may be at play

Efecto del cambio climático sobre las interacciones planta-animal y sus consecuencias sobre los ecosistemas

Las comunidades ecológicas están organizadas en redes complejas de interacción donde las especies se relacionan unas con otras a través de diferentes tipos de interacciones. Las interacciones mutuamente benéficas entre plantas y sus polinizadores y dispersores de semillas tienen una gran influencia en la dinámica de la comunidad y han contribuido a generar la biodiversidad sobre la Tierra. Además, las interacciones mutualistas planta-animal son claves en proveer funciones y servicios ecosistémicos. El cambio climático es una amenaza significativa para las especies y sus interacciones en las comunidades ecológicas, con el potencial de modificar funciones y servicios ecosistémicos claves como la polinización y la dispersión de semillas. Las interacciones mutualistas son especialmente vulnerables a ser afectadas por el cambio climático debido a su alta sensibilidad al desacople fenológico si las especies que interactúan no responden de manera similar a los cambios ambientales. En interacciones planta-polinizador y planta-dispersor de semilla, el desacople fenológico puede afectar a las plantas causando una reproducción reducida, mientras que los polinizadores y dispersores de semilla se ven afectados por una menor disponibilidad de alimento. La declinación de polinizadores y dispersores de semilla puede conducir a la pérdida de interacciones en las comunidades, lo cual puede a su vez onducir al colapso de las funciones y servicios ecosistémicos que mantienen. Estas consecuencias podrían ser particularmente severas en los trópicos, donde existe una alta dependencia de la polinización y dispersión de semilla por medio de animales

Perception of the Severity of COVID-19 Contagion in the Risk Group. A Comparative Study at the First and the Ninth Months of Compulsory Isolation.

After the continued extension of the quarantine due to the COVID-19 pandemic, it was proposed to investigate the perception of the severity of contagion in the risk group of the population. For this purpose, a descriptive cross-sectional study was carried out through the online distribution of surveys, consisting of a sociodemographic questionnaire and questions related to the perception of the severity of the disease. Two comparative moments were considered: the first month and the ninth month of quarantine. The random sample consisted of 4268 individuals, of whom 1006 respondents stated that they were part of a risk group. Regarding the results, it was observed that although the perception of the risk of contagion decreased over the months, the highest risk remained "very high" (in the first month - 46.7 percent and in the ninth month - 38.5 percent), increasing the values of "medium risk" (in the first month - 20.4 percent; in the ninth month - 28.6 percent) and "high risk" (in the first month - 16.0 percent; in the ninth month - 20.8 percent). However, the difference was not statistically significant (the Wilcoxon rank test was applied and a value of p = 0.6 was obtained). In turn, the research allows us to compare the results with those of the perception of the population as a whole and compare the values of the risk group who contracted the virus, with whom they did not.   Cite this paper: Ceberio, Marcelo R.; Agostinelli, Jesica; Benedicto, Gabriela; Cocola, Facundo; Jones, Gilda; Díaz Videla, Marcos; Calligaro, Carolina; Daverio, Romina (2022). "Perception of the severity of COVID-19 contagion in the risk group. A comparative study at the first and the ninth months of compulsory isolation" Journal of Social Sciences: Transformations &amp; Transitions (JOSSTT) 2 (03):12. DOI: https://doi.org/10.52459/josstt2312012