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Long-Term Hydrological Impacts of Historical Logging on Recent Hydro-Geomorphic Conditions, Big Barren Creek Watershed, Mark Twain National Forest
No full textDespite their important role of headwater watersheds as a buffer for upland soil and vegetation disturbances, there has been little research about the effects of historical logging practices on present-day watershed hydrology and channel form. Middle Big Barren Creek (MBBC) watershed (48 km2 ) drains Mark Twain National Forest in the Ozark Highlands and was heavily logged from 1880 to 1920, reducing native shortleaf pine forest by 90%. Additionally, the frequency of intense rainfall events has increased in the region over the past 30 years. In this study, field surveys and hydrologic/hydraulic modeling were used to evaluate the historical timber harvesting impacts on hydrology and channel hydraulics along a 4.5 km segment of MBBC. The models were accurately calibrated with actual gage discharge data and water surface elevations yielding a Nash-Sutcliffe coefficient value of 0.85 and R2 = 1. Four different land use/cover scenarios were assessed to understand the history of hydrological alteration with five hydrologic parameters (flow duration, average discharge, runoff depth, peak discharge, and lag time ) and three hydraulic parameters (shear stress, stream power, and velocity). Pine forest cover tended to reduce runoff with the present-day peak discharge predicted to be 23% higher than with 100% pine cover, but 3% lower with 100% hardwood forest cover. Change from pine to hardwood forest composition caused reduced canopy interception (-29%) and higher peak flow (+60%) during a modeled early spring rainstorm. Compared to the pre-settlement condition, present-day shear stress (SS) increased among channel types for a bank-full flood as follows: (i) multi-threaded, 29%; (ii) single-channel, 59% and (iii) channelized/leveed 19%. Therefore, the single-channel form probably indicates a geomorphic response to higher runoff rates in these forest streams including coarser substrates. In the study segment, artificial over-widening of the channel resulted in bed aggradation
Historical Changes of Channel Width in a Headwater Stream System, Mark Twain National Forest, Missouri
No full textIt is well known that watershed disturbances due to land clearing and agricultural settlement during the early 1800s changed the hydrology and geomorphology of stream systems in the Midwestern USA. However, little is known about the impacts of historical logging on stream systems in forested watersheds. This study evaluates channel width measurements from 38 General Land Office (GLO) surveys completed in 1821, aerial photographs from the 1930’s to present, and LiDAR imagery from 2016/17 to evaluate changes in channel morphology in Big Barren Creek in Mark Twain National Forest in the Ozarks Highlands of southeast Missouri. The area was heavily logged for pine between 1880 and 1920 and today is being managed for both pine forest restoration and cyclical tree harvesting. Overall, modern channel widths have increased by an average of 2.6 times since 1821. The largest increases occurred in second order streams averaging a 3.4-fold increase, while no change in width occurred in a 2 km long 4th order confined bedrock-controlled segment. It is suggested that the primary cause of channel widening was the increase in runoff due to deceased canopy interception of rainfall after removal of short-leaf pine by exploitive logging and replacement by hardwoods. Apparently, recent climate change resulting in more intense rains and frequent floods has caused channel width to increase at some sites by an average of 1.6 times since 2007
Working Memory as a Predictor of Social Distancing and Face Mask Compliance During COVID-19 Pandemic
No full textThe COVID-19 pandemic has brought about many changes in daily lives around the world. In the United States, face masks and social distancing rules have been suggested and even enforced in areas throughout the country. Compliance with these regulations will in turn, hopefully, reduce transmission and therefore the threat of the COVID-19 virus. Working memory (WM) has been found to be an integral part of the decision-making process, by assessing costs and benefits, both individually and for others. In May 2019, Xie, Campbell, and Zhang (2020) found that WM capabilities were predictive of social distancing compliance. The purpose of this research project was to do a partial replication of Xie et al. (2020) by investigating the predictive validity of WM, perceived benefits over costs, and anxiety on social distancing and face mask compliance. Two hundred-fourteen participants were recruited via Amazon M Turk. Participants completed a visual working memory localization task (VWMLT), a series of questionnaires on demographics, social distancing compliance, face mask compliance, a perceived benefits over costs analysis of compliance, and anxiety. Two hierarchical multiple regression analyses and two tests for mediation were employed to best explain individual differences in compliance behavior. Working memory capacity was found to be a significant predictor of social distancing compliance when accounting for anxiety (b = 0.65, p \u3c .01), but was not for face mask compliance (b = 0.11, p \u3e .05). Perceived benefits over costs did not mediate the relationship between WM capacity and either social distancing or face mask compliance. The results of this project contribute to our understanding of individual differences in cognitive processing and how such differences relate to human behavior considering a global pandemic. Given an understanding of the link between WM and social behavior may then provide a means to further research the connection between the theoretical basis of WM in decision making
Grapevine Vein Clearing Virus Is Prevalent and Genetically Variable in Grape Aphid (Aphis Illinoisensis Shimer) Populations
No full textGrapevine vein clearing virus (GVCV) causes severe stunting and death of cultivated grapevines and is prevalent in native Vitis spp. and Ampelopsis cordata in the Midwest region of the United States. GVCV can be transmitted from wild A. cordata to Vitis spp. by grape aphid (Aphis illinoisensis) under greenhouse conditions, but its prevalence, genetic composition, and genome number in native grape aphids are unknown. In this study, we collected grape aphids from native Vitaceae across the state of Missouri in 2018 and 2019, and conducted diagnostic, genetic, and quantitative analyses. GVCV was detected in 91 of the 105 randomly sampled communities on 71 Vitaceae plants (87%). It was present in 211 of 525 single grape aphids (40%). Diverse GVCV variants from aphids were present on both GVCV-negative and GVCV-positive plants. Identical GVCV variants were found in grape aphids sampled from wild and cultivated Vitaceae, indicating that viruliferous aphids likely migrate and disperse GVCV variants among wild and cultivated Vitaceae. In addition, we found that the number of GVCV genomes varies largely in the stylet and body of individual aphids. Our study provides a snapshot of GVCV epidemics and genetic structure in its mobile vector and sessile hosts. This presents a good model for studying the epidemiology, ecology, and evolution of a plant virus
Income Predicts FPG, but Food Security is the Mediator
No full textThis research was aimed at studying the RISE pilot program and stability factors of low socioeconomic groups. Self-sufficiency programs focus on households moving from crisis to empowerment; no longer relying on subsidies. Gaining employment and housing alone do not create socioeconomic stability. It was therefore determined that the RISE Program should be evaluated to determine the effectiveness at ending dependency. Methods: Thirty-four (30.6%) participants were included in this evaluation. Using logistic regression techniques, sixteen items on the RISE Self-sufficiency Assessment were explored. Results: RISE participants derived significant economic benefits, and that food security seemed to be the greatest mediator of increased %FPG. The slope of the overall RSSA revealed every one increase in the total RSSA score, there were 24.01 increases in %FPG. Participants who had increased food security saw significant increases in %FPG of 25.25. Conclusion: Participants’ perceptions of improved food security is the best mediator of increased federal poverty guidelines
Video Error Concealment Using Convolutional Neural Network
No full textMissing information in the video frames is estimated as close as possible to the actual data during video error concealment process. Blocks or slices of information in the video frames can be missing in the decoder due to various reasons like corrupt media drives, network congestion, etc. which reduces the quality of experience for the viewers. One approach to deal with missing information in the video decoder is to use error concealment techniques to fill the missing information. Until now many of these error concealment techniques were based on conventional methods such as block copy, motion vector prediction, and interpolation. In this thesis, I propose Convergent Error Concealment Neural Network (CECNN) for video error concealment. It is based on the Convolutional Neural Network (CNN) architecture that takes an errored frame as input and gives an error concealed frame as output. I applied transfer learning to produce intermediate outputs and combine them to fill the missing information in the errored frames. Unlike commonly used single path neural network architecture, my proposed CECNN consists of separate paths for the preceding and succeeding frames to produce the intermediate outputs. It also supports a single path using the preceding frames for time-sensitive use cases, such as real-time video. Experimental results confirm that my proposed network gives better error concealed output for real-time video communication. Quality metrics like MS-SSIM, PSNR, and MSE are used to calculate and compare the quality of my proposed technique’s output with the output obtained from motion vector estimation, neighboring motion vectors, and neural network-based generative image inpainting. The experimental results show that my CECNN approach is a good candidate to replace the existing conventional techniques to error conceal the errored frames in any video decoder
Code-Switching in Spoken Indian English: A Case Study of Sociopolitical Talk
No full textIn India, the prevalence of (Indian) English and code-switching between languages is not new. However, there has been a dearth of research that explores code-switching in Indian English (IE) within the genre of sociopolitical talk in Indian English tv talk shows. The current study is a part of a larger longitudinal study that analyzes code-switching patterns across the previous decade in Indian English tv talk shows and is the first in the series of follow-up studies. This study qualitatively examines an episode of an Indian English tv talk show to determine code-switching (CS) patterns and functions in IE. The study employed linguistic analysis, Meyerhoff’s (2007) accommodation theory, Sacks, Schegloff, and Jeferrson’s (1974) conversation analysis methodology, and a world Englishes framework to discover the forms, functions, and motivations of CS in an English matrix context. Findings confirm Si’s (2010) results that speakers preferred higher number of English alternations and insertions than Hindi code-switches, while Hindi-only turns were relatively few. Functions of analyzed code-switches also indicated intentions to reformulate, repeat, quote, connect with or diverge from other interlocutors, and generate emphasis in discourse. The study concludes with implications for Indian English and avenues for future research
What money can buy: technology and breaking the two-hour ‘marathon’ record
No full textOn 12 October 2019, Kenyan runner Eliud Kipchoge became the first person to run a ‘marathon’, known as the INEOS 1:59 Challenge, in less than 2 hours in a time of 1:59:40.2. However, his time was not ratified as a world record by World Athletics. We not only explain why this phenomenal achievement was not recognized as a legitimate record but argue his sub 2-h ‘marathon’ run produced a meaningless ‘record’ because the feat was not part of a contest. His run was an experiment or time trial spectacle backed by the best scientists, technology, organizers, athletes, conditions, and media coverage money can buy. Four areas buttress our argument: the selective use of technology, the concept of a record, the distinction between a test and contest, and the meaning of a marathon. We conclude by presenting an account of what makes a marathon record meaningful
Uranium carbonate complexes demonstrate drastic decrease in stability at elevated temperatures
No full textQuantitative understanding of uranium transport by high temperature fluids is crucial for confident assessment of its migration in a number of natural and artificially induced contexts, such as hydrothermal uranium ore deposits and nuclear waste stored in geological repositories. An additional recent and atypical context would be the seawater inundated fuel of the Fukushima Daiichi Nuclear Power Plant. Given its wide applicability, understanding uranium transport will be useful regardless of whether nuclear power finds increased or decreased adoption in the future. The amount of uranium that can be carried by geofluids is enhanced by the formation of complexes with inorganic ligands. Carbonate has long been touted as a critical transporting ligand for uranium in both ore deposit and waste repository contexts. However, this paradigm has only been supported by experiments conducted at ambient conditions. We have experimentally evaluated the ability of carbonate-bearing fluids to dissolve (and therefore transport) uranium at high temperature, and discovered that in fact, at temperatures above 100 °C, carbonate becomes almost completely irrelevant as a transporting ligand. This demands a re-evaluation of a number of hydrothermal uranium transport models, as carbonate can no longer be considered key to the formation of uranium ore deposits or as an enabler of uranium transport from nuclear waste repositories at elevated temperatures
Observing Changes in Vegetable Production through Alternative Agricultural Practices
No full textLocally, responsibly grown produce is becoming more popular as consumers are shifting to organic products or those obtained at a local farmer’s market. The importance of soil health through conservation practices is increasing as the negative effects of industrial production are apparent. The over-application of synthetic fertilizers, soil erosion from wind and water, and nutrient leaching in high vegetable production areas has initiated a need for the investigation of alternative management practices. The main objective of this study is to evaluate the effects of tillage and cover crops in the production of green beans and okra. In 2019 and 2020, Blue Lake green beans and Clemson Spineless okra were planted at the Missouri State University Darr Agricultural Center. Tillage and no-till treatments were applied for the 2019 growing season, and cover crop treatments were implemented in November of 2019 for the 2020 growing season. Vegetable harvests were conducted throughout both growing seasons to determine calcium (Ca), phosphorus (P), magnesium (Mg), and potassium (K) concentrations in produce as well as yield. Soil nutrient content was determined from soil samples collected after the 2020 growing season. Green beans showed a statistically significant increase in tillage plots for growth rate in both seasons as well as yield in 2020. No significance was found in okra through any treatment method. These findings suggest that tillage increases short-term green bean production in regards to yield, but does not affect the productivity of okra