6 research outputs found
Effects of selected surfactants on nutrient uptake and soil microbial community
Title from PDF of title page (University of Missouri--Columbia, viewed on June 6, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisors: Dr. Robert J. Kremer, Dr. Frieda Eivazi, Dr. Kelly Neldon, and Dr. Peter P. MotavalliIncludes bibliographical references.M.S. University of Missouri--Columbia 2011."December 2011"Surfactants with solvent and wetting abilities are used in the formulation of herbicides to enhance spraying capabilities. These chemicals eventually enter into the soil and may disrupt different chemical, physical and biological processes. The aim of this study was to examine the effects on nutrient uptake in corn and soil microbial community due to application of surfactants at different rates, herbicides, and surfactant-herbicide combinations in silt loam and silty clay loam soils. Surfactants used were Activator 90, Agri-Dex and Thrust. Herbicides used were glyphosate, atrazine, and bentazon. Corn was planted in fertilized soils and moisture levels maintained. After seven weeks, plant foliage were ground and stored for elemental analyses with Inductively Coupled Plasma Emission Spectrophotometer (ICP). Soil samples were analyzed with Polymerase Chain Reaction (PCR-DGGE) and Phospholipid Fatty Acids analyses (PLFA) to assess microbial diversity. The treatments did not greatly affect nutrient uptake by corn. Visual differences between both soils and among treatments were observed with DNA band expression, although few significant differences due to treatments were found. PLFA biomarkers were variably affected by soils and different treatments relative to control. In general treatments did not significantly affect plant nutrient uptake or microbial community, perhaps as a result of the onetime application of small quantities of chemicals. Differences between both soils reflected the overall contribution of soil texture, chemical and physical characteristics. Formulation additives should be considered when evaluating effects of pesticide applications on plant quality and soil biology
Conversion of waste corncob to activated carbon for use of methane storage
Abstract only availableMissouri being one of the leading states in corn production has a large quantity of corn cobs. Corn cob can be used to produce activated carbon because its organic origin is similar to coconut and peach pits which have been previously used to make activated carbons. In this project, researchers at the University of Missouri Columbia are using adsorbents produced from corn cobs to store natural gas. Results have shown that a BET surface area of 800m2/g-1600m2/g can be obtained. Scanning Electron Microscope (SEM) images confirms that micro porous nature of the carbon. The main objective of this research is to develop flat low pressure high capacity natural gas tank holding no greater than 500psi of methane, allowing for more trunk space in cars. It is anticipated that the new Absorbed Natural Gas (ANG) will be the competitor with Compressed Natural Gas (CNG) which is currently stored in heavy tanks at high pressures of about 3600psi. Activated carbons obtained from the corn cob that has been through chemical activation process are used to make monoliths, in order to achieve the maximum density. The powdered form of the activated carbon is combined with a binding agent and pressed using a hydraulic press and die. By this process corn cobs can be converted into monolithic carbon and having methane uptake of 150v/v or more.NSF Program Alliance for Collaborative Research in Alternative Fuel Technology and Louis Stokes Missouri Alliance for Minority Participatio
By-product Formation in Respect of Operating Conditions on Conversion of Glycerol to Propylene Glycol [abstract]
Abstract only availableFaculty Mentor: Dr. Galen Suppes, Chemical EngineeringThe conversion reaction of glycerol to propylene glycol (PG) results in the yield of different products namely acetol, water, PG and it has also shown little selectivity toward ethylene glycol and other unknown by-products. These unidentified compounds are consequently called âunknownsâ. In order to maximize the production of propylene glycol these unknown by-products have to be reduced. To properly assess the unknowns, Gas Chromatograph (GC) testing is done on the finish product in order to create new methods to eradicate the unknowns. PG and seven of the most prominent unknowns were chosen to carry out the study where the trends are studied in relation to propylene glycol and reaction conditions. The seven unknowns are named as the retention time shown in the gas chromatogram 8.74, 8.78, 9.11 (Ethylene Glycol), 9.15, 9.28, 9.32, and 9.405. The impact of two independent reaction parameters were investigatedâreferred to as Parameter A (PA) and Parameter B (PB). At higher PA less unknown are produced during the reaction. The value of PB applied in this reaction is very critical as the higher values result in the production of more unknowns and less PG in the end product. Based on this analysis, the reaction should be conducted at higher value of PA and low PB.Louis Stokes Missouri Alliance for Minority ParticipationMissouri Soybean Merchandizing Counci
Breast cancer management pathways during the COVID-19 pandemic: outcomes from the UK âAlert Level 4â phase of the B-MaP-C study
Abstract: Background: The B-MaP-C study aimed to determine alterations to breast cancer (BC) management during the peak transmission period of the UK COVID-19 pandemic and the potential impact of these treatment decisions. Methods: This was a national cohort study of patients with early BC undergoing multidisciplinary team (MDT)-guided treatment recommendations during the pandemic, designated âstandardâ or âCOVID-alteredâ, in the preoperative, operative and post-operative setting. Findings: Of 3776 patients (from 64 UK units) in the study, 2246 (59%) had âCOVID-alteredâ management. âBridgingâ endocrine therapy was used (n = 951) where theatre capacity was reduced. There was increasing access to COVID-19 low-risk theatres during the study period (59%). In line with national guidance, immediate breast reconstruction was avoided (n = 299). Where adjuvant chemotherapy was omitted (n = 81), the median benefit was only 3% (IQR 2â9%) using âNHS Predictâ. There was the rapid adoption of new evidence-based hypofractionated radiotherapy (n = 781, from 46 units). Only 14 patients (1%) tested positive for SARS-CoV-2 during their treatment journey. Conclusions: The majority of âCOVID-alteredâ management decisions were largely in line with pre-COVID evidence-based guidelines, implying that breast cancer survival outcomes are unlikely to be negatively impacted by the pandemic. However, in this study, the potential impact of delays to BC presentation or diagnosis remains unknown
Effects of urban living environments on mental health in adults
Urban-living individuals are exposed to many environmental factors that may combine and interact to influence mental health. While individual factors of an urban environment have been investigated in isolation, no attempt has been made to model how complex, real-life exposure to living in the city relates to brain and mental health, and how this is moderated by genetic factors. Using the data of 156,075 participants from the UK Biobank, we carried out sparse canonical correlation analyses to investigate the relationships between urban environments and psychiatric symptoms. We found an environmental profile of social deprivation, air pollution, street network and urban land-use density that was positively correlated with an affective symptom group (râ=â0.22, Ppermâ<â0.001), mediated by brain volume differences consistent with reward processing, and moderated by genes enriched for stress response, including CRHR1, explaining 2.01% of the variance in brain volume differences. Protective factors such as greenness and generous destination accessibility were negatively correlated with an anxiety symptom group (râ=â0.10, Ppermâ<â0.001), mediated by brain regions necessary for emotion regulation and moderated by EXD3, explaining 1.65% of the variance. The third urban environmental profile was correlated with an emotional instability symptom group (râ=â0.03, Ppermâ<â0.001). Our findings suggest that different environmental profiles of urban living may influence specific psychiatric symptom groups through distinct neurobiological pathways