858 research outputs found
Disinfectant Efficacy Against SARS-CoV-2 Surrogates, Bovine Coronavirus and Human Coronavirus OC43, on Hard and Soft Non-porous Surfaces
The novel human coronavirus (HCoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged from Wuhan, China in the latter part of 2019. The rapid spread of SARS-CoV-2 amid the most recent COVID-19 pandemic forced countless foodservice establishments (FSEs) across the United States to close, taking a tremendous toll on the foodservice industry. Although primarily transmitted person-to-person, previous studies indicate that the duration of SARS-CoV-2 survival on different environmental surfaces provides adequate time for secondary transmission to occur. To prevent the further spread of SARS-CoV-2, effective disinfection of surfaces in FSEs is necessary. While disinfectants approved for use against SARS-CoV-2 are found on the Environmental Protection Agency’s (EPA’s) List N, there is limited data available regarding the efficacy of these products against two SARS-CoV-2 surrogates, bovine coronavirus (BCoV) and human coronavirus OC43 (HCoV OC43) on surfaces other than glass and stainless steel. Therefore, our aims for this study were to (I) optimize a neutralization method for chlorine- and quaternary ammonium compound (QAC)-based disinfectants during efficacy testing, (II) determine the efficacy of two separate batches of three ready-to-use (RTU) spray disinfectants of different active ingredients (chlorine, hydrogen peroxide, and QAC + alcohol) against SARS-CoV-2 surrogates, BCoV and HCoV OC43, in suspension and (III) on surfaces commonly found in the ‘front-of-the-house’ in FSEs (polyethylene terephthalate [PET] plastic and vinyl upholstery fabric). Cytotoxicity to the host cell line during efficacy testing was successfully eliminated via infection media paired with centrifugation in PierceTM detergent removal columns for the QAC-based disinfectant, and a 5% fetal bovine serum (FBS) + 1% sodium thiosulfate (Na2S2O3) solution for the chorine-based disinfectant. In suspension testing, all three RTU disinfectants tested achieved a \u3e3.0 log10 reduction of BCoV and HCoV OC43 within 2 min. On PET carriers, all three RTU disinfectants reduced BCoV by \u3e3.0 log10 TCID50/mL, whereas Oxivir Tb was the only disinfectant efficacious against BCoV on vinyl carriers. None of the three RTU disinfectants tested achieved a \u3e3.0 log10 reduction of HCoV OC43 on PET or vinyl. However, after a 2 min contact time, all three disinfectants reduced the infectivity of BCoV and HCoV OC43 below the limit of detection (LOD) on both PET and vinyl surfaces. Those cases with \u3c3.0 log10 reduction of virus titer were due to the decreased dynamic range on the carrier prior to disinfection. Further analysis of carrier test results revealed that the mean reduction in titer of BCoV and HCoV OC43 after drying was greater on vinyl carriers. In addition, greater amounts of reduction of BCoV and HCoV OC43 were observed on both PET and vinyl carriers as the relative humidity (RH) level increased. At low RH (20-29%) conditions, the reduction in the titer of HCoV OC43 was significantly greater than that of BCoV on both PET and vinyl carriers. Our data showed that both SARS-CoV-2 surrogates are very sensitive to the tested disinfectants, and further analysis of the quantitative carrier test data indicates that additional factors (i.e., surface type, RH, and surrogate) must be carefully considered when performing disinfectant efficacy testing on carriers. Collectively, these data highlight the importance of verifying disinfectant suspension test data by performing disinfectant carrier tests which expose the virus and disinfectant to conditions (i.e., surface type, relative humidity, surrogate) similar to those encountered during ‘real-world’ application
Searching for the Spirit of Crazy Horse: A Rhetorical Analysis of Competing Myths
In this thesis I look at three different biographical reconstructions of Crazy Horse that construct the famous Lakota man as a mythic hero. Through the lens of myth and narrative theory, I identify three different ways in which Crazy Horse has been portrayed as a heroic individual: 1) as a heroic warrior for his leadership role in defeating U.S. forces at the Battle of the Little Bighorn 2) for his generosity to his people in a time of traumatic change and 3) for his willingness to sacrifice his life to end the violent conflict between Sioux and U.S. military. I argue that Crazy Horse presents a unique opportunity for biographers to offer competing myths about his life because we know so little about him, aside from his accomplishments. Thus, the lack of primary resources about the life of Crazy Horse provides an opportunity for the biographer to construct Crazy Horse in a way that serves their own purpose in telling his story
The examination of position selection, job provisions, working environment satisfaction on teaching performance and commitment
The purpose of the study was to develop and test a hypothetical model that examined factors that influence teacher performance and commitment of Iowa State University (ISU) teacher education graduates. Position selection, job provisions, working environment satisfaction, teaching performance, teaching efficacy, and commitment provided the framework for the development of the model. The measurement point was five years following graduation;The model was tested using survey data collected from the five-year follow-up study of ISU teacher education graduates. Those who graduated in 1982-83 and 1983-84 and were teaching at the time of the survey (N = 245) provided the data;Results of full recursive path analysis of the model yielded 12 significant paths. The final variable in the path analysis was commitment orientation. Leadership, extrinsic and intrinsic satisfaction, and teaching efficacy provided the significant predictor variables;The same variables were used as predictors in a discriminant analysis of commitment. Of the 11 predictors, 4 proved significant. These were: commitment orientation, humanistic qualities of job provisions, intrinsic satisfaction in the working environment, and teaching efficacy
Interior Least Terns (Sternula antillarum athalassos) in a Landscape of Fear: Explaining Predator Frequency on Sandbars Using Habitat Features
Causes of colony failure in interior least terns (Sternula antillarum athalassos) have been a prevalent topic for researchers investigating this previously endangered species. In Arkansas, these colonies are primarily located on sandbars formed along the McClellan-Kerr Arkansas River Navigation System. Reduction in nesting site quality may put this sensitive species at a greater risk for predator encounters. In my first chapter, I identified which sandbar characteristics resulted in higher frequencies of predator encounters at interior least tern colonies. In my second chapter, I investigated how those predators influenced colony production and whether interior least tern colonies exhibited similar associations to those site characteristics. I used colony surveys from the summer 2020 and 2021 nesting seasons for my investigations. Commonly identified predators included American crows (Crovus brachyrhynchos), bald eagles (Haliaeetus leucocephalus), coyotes (Canis latrans), domestic dogs (C. familiaris), and northern raccoons (Procyon lotor). I studied fourteen characteristics representative of sandbar morphometrics. Generalized additive models were used to quantify the relationships between those site characteristics and avian predators, mammalian predators, and ILT reproductive success. Interior least tern colonies were located on larger sandbars further away from upriver dams. This study highlights the importance of sandbar size, shape, and location on waterbodies for ILT colony use. These factors were important for ILT production and explaining predator counts at sandbars. This study suggests that, while interior least tern conservation management usually focuses on local habitat features, landscape-scale features may be driving ILT production as well as predator encounters on Arkansas River sandbars
Benefit Corporation Legislation: An Opportunity for Kansas to Welcome Social Enterprises
This is the published version
Finding Resolutions of Mononomial Ideals
In this paper we present two different combinatorial approaches to finding resolutions of polynomial ideals. Their goal is to get resolutions that are as small as possible while still preserving the structure of the zeroth syzygy module. Then we present the idea of a differential graded algebra and discuss when the minimal resolutions of a polynomial ideals admits such a structure
KEKF R1 Reservoir - West Delta Block 84, Plaquemines Parish, Louisiana - an analysis and confirmation of bypassed primary and secondary reserves
West Delta Block 84 Field is located off the coast of Plaquemines Parish, Louisiana. The intent of this endeavor is to prove that the two of the reservoirs, the KE-1 and KF-1, form a single communicating reservoir, the KEKF-R1; that a waterflood into the KF-1 reservoir was ineffective; that oil reserves were bypassed; and that a portion of these bypassed oil reserves can be recovered without drilling new wells. Comparisons between pre-seismic and post-seismic geological interpretations were studied, a thorough volumetric analysis was performed with a subsequent material balance calculations and a reservoir computer simulation was performed. Once a history match was made, prediction studies were performed for both remaining “primary” reserves and for secondary reserves recoverable through a new water-flood design and implementation. There are many new insights on this reservoir as a result of this study. First, the KE-1 and the KF-1 reservoirs are indeed one communicating reservoir. The KF-1 waterflood was inefficient and resulted in bypassed oil pay. Bypassed oil may be recovered through several techniques. Based on prediction runs on BOAST, the best case scenario analyzed thus far without additional drilling is an additional 1,600,000 barrels of oil. This study indicates that a small amount of old technology, in the form of a resurrection of a waterflood and a small amount of new technology, in the form of the Downhole Water Sink (DWS) method will greatly increase the ultimate recovery of the “lost” reserves. This study has provided sufficient evidence and documentation to justify the need for additional research and study of this reservoir. More detailed recovery strategies should be prepared, the DWS technology should be studied in more detail and a more detailed grid should be prepared for the reservoir
The Rise of Nixon
Richard Milhous Nixon is one of the most central political figures in American history. Therefore, an analysis of how he rose to national prominence, and so quickly at that, is a worthwhile discussion. For example, Nixon entered the United States House of Representatives in 1946 by defeating the popular Democratic incumbent, Jerry Voorhis. Without previous political experience, Nixon was thrown into Congress where he was promptly placed on the infamous House Committee on Un-American Activities (HUAC). There he gained national fame in the case of Alger Hiss, an accused communist spy. He followed this with a stunning victory in the 1950 senatorial race against Helen Gahagan Douglas. Soon after, Nixon was nominated as the vice presidential candidate in 1952. At the young age of forty, and just six years after his first political campaign, Nixon entered the White House as Dwight D. Eisenhower's vice president. Nixon's meteoric rise to power begs the question of just how exactly he accomplished this feat. The answer to this question is quite simple: Nixon used the issue of communist subversion to further his political career. In fact, the perceived communist threat of the post-World War II era was the chief catalyst in Nixon's rise to the forefront of American politics. His career gained momentum alongside the Red Scare of this era with his public battles against accused communist sympathizers
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