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Age- And Speed-Related Differences In Walking Smoothness, Kristin Ann Lowry 2010 Iowa State University

Age- And Speed-Related Differences In Walking Smoothness, Kristin Ann Lowry

Graduate Theses and Dissertations

Extensive literature documents age-related differences in spatiotemporal variables during gait. Recent efforts have focused on upper body control and balance during gait. Harmonic ratios, derived from trunk acceleration signals, measure smoothness of motion, and are an indication of dynamic balance during gait. Limited and conflicting information exists regarding the effect of walking speed on harmonic ratios, as well as age-related differences. This research extends previous literature by: 1) examining harmonic ratios across a range of self-selected speeds in young adults; 2) comparing harmonic ratios at preferred speed in young adults, healthy 60-year-olds, and healthy 80-year-olds; and 3) comparing harmonic ratios ...


The Effect Of Heel Height On Frontal Plane Joint Moments, Impact Accelertion, And Shock Attenuation During Walking, Danielle Barkema 2010 Iowa State University

The Effect Of Heel Height On Frontal Plane Joint Moments, Impact Accelertion, And Shock Attenuation During Walking, Danielle Barkema

Graduate Theses and Dissertations

Wearing high heels alters walking kinematics and kinetics and can create potentially adverse effects on the body. Our purpose was to determine how heel height affects frontal plane joint moments at the hip, knee, and ankle, with a specific focus on the external knee moment due to its importance in medial loading and knee osteoarthritis. In addition, this study examined the effect of heel height on impact acceleration of tibia and head and shock attenuation of the body. Fifteen women completed overground walking trials in three different heel height conditions (1, 5, and 9 cm) for a fixed walking speed ...


Mediolateral Stability During Gait In People With Parkinson's Disease, Sudeshna Aloke Chatterjee 2010 Iowa State University

Mediolateral Stability During Gait In People With Parkinson's Disease, Sudeshna Aloke Chatterjee

Graduate Theses and Dissertations

Gait control is a clinical problem in people with Parkinson's disease (PD). Gait variability leading to instability is commonly measured using spatio-temporal variables like step length, step time, step width and cadence. Another measurement that provides information about directional instability is harmonic ratios (HRs). The purpose of this study was to examine the relationship between step width and mediolateral stability using HRs in people with Parkinson's disease (n = 19) and age matched controls (n = 19). The participants walked at their preferred pace and then with a wider step width and narrower step width. The results showed that the ...


Double-Cropping Sorghum For Biomass Production, Ben Michael Goff 2010 Iowa State University

Double-Cropping Sorghum For Biomass Production, Ben Michael Goff

Graduate Theses and Dissertations

The production of biomass using double-cropping systems may have the advantage of producing more feedstock for refineries by extending the growing season, while also providing many environmental benefits, such as the reduction of erosion. Past research indicates that there may be a genotypic effect for the suitability of a crop for use within these systems. There has been little research conducted to explicitly examine this effect in sorghum, despite the crop's diverse genetic background. The objective of this study was to evaluate the biomass production of twelve sorghum genotypes grown as a sole crop and within a double-cropping system ...


Local And Regional Approaches To Studying The Phenology And Biological Control Of The Soybean Aphid, Nicholas P. Schmidt 2010 Iowa State University

Local And Regional Approaches To Studying The Phenology And Biological Control Of The Soybean Aphid, Nicholas P. Schmidt

Graduate Theses and Dissertations

Soybean aphids Aphis glycines Matsumura (Hemiptera: Aphididae) are an economic pest of soybean Glycine max (L.) Merr. in much of the United States and parts of Canada. Some crucial phenological information of A. glycines is unknown, specifically source-sink dynamics between and within host plants and factors guiding aphid migrations. In addition, there are discrepancies in the literature on the importance of food webs and how local landscape effects can alter A. glycines populations. Increasing our understanding of A. glycines population dynamics may improve predictions of aphid outbreaks and integrated pest management efforts. The first objective was to determine how landscape ...


Tillage Effects On Soybean Growth, Development, And Yield, Alecia Marie Kiszonas 2010 Iowa State University

Tillage Effects On Soybean Growth, Development, And Yield, Alecia Marie Kiszonas

Graduate Theses and Dissertations

Profit margins of soybean [Glycine max (L.) Merr.] in the United States have recently declined as a result of an increase in production and land costs. Decreased profits coupled with increasing environmental concerns such as erosion and runoff prompts more cost-efficient production practices. No-tillage production practices offer a lower cost of production in addition to decreased soil erosion and runoff. Additionally, soil quality can be improved over time in a no-tillage system, greatly increasing the yield benefits over time. Today, only 41% of Iowa's soybean production is under no-tillage production (Conservation Technology Information Center, 2010), although even more of ...


The Effects Of Previous-Year Corn Hybrid And Cropping System On Current-Year Corn Hybrids In Second Year Corn, Wade Adam Kent 2010 Iowa State University

The Effects Of Previous-Year Corn Hybrid And Cropping System On Current-Year Corn Hybrids In Second Year Corn, Wade Adam Kent

Graduate Theses and Dissertations

Grain yields decrease when corn (Zea mays L.) follows corn compared to corn grown in rotation with other crops. The factors that decrease grain yield of corn following corn are not well understood, and limit recommendations available to corn growers. Our objectives were to determine (i) if plant population, moisture, and yield of 2nd year corn are affected by the previous-year corn hybrid, (ii) evaluate if continued use of single hybrid over two growing seasons influences grain yield, and (iii) compare 2nd year corn yields to corn grown in rotation with soybean. The experiment was conducted at six ...


Phosphorus Sorption-Desorption Of Soils And Sediments In The Rathbun Lake Watershed, Najphak Hongthanat 2010 Iowa State University

Phosphorus Sorption-Desorption Of Soils And Sediments In The Rathbun Lake Watershed, Najphak Hongthanat

Graduate Theses and Dissertations

Livestock grazing in pastures has been identified as a possible factor controlling sediment and phosphorus (P) delivery to Rathbun Lake and associated water bodies in the watershed. The risk of P loss from soils in this watershed was estimated by Mehlich-3 (M3) extractable P, P sorption indices (Smax and k), degree of P saturation (DPS) and P desorption indices (equilibrium phosphorus concentration (EPC) and phosphorus equilibrium buffering capacity (PEBC)) for seven representative soil samples. Most of selected soils had low risk of P loss as indicated by PM3 and DPS. However, EPC values indicated that some soils could ...


Detection, Fate, And Bioavailability Of Erythromycin In Environmental Matrices, Ashley M. Jessick 2010 Iowa State University

Detection, Fate, And Bioavailability Of Erythromycin In Environmental Matrices, Ashley M. Jessick

Graduate Theses and Dissertations

This thesis focuses on the environmental effects of the macrolide antibiotic erythromycin from livestock production practices and its possible influence in aquatic ecosystems. The veterinary antibiotic, erythromycin, is used for disease prevention and growth promotion in livestock. Erythromycin has been frequently detected in streams and sediments in the U.S. The widespread use of veterinary antibiotics in agriculture has led to increased concern about their environmental fate. For this research, a microcosm system was utilized to monitor the fate (including movement, binding, and degradation) along with bioavailability of the compound to aquatic invertebrates. The bioavailability study included the development of ...


Genistein Mediates Perturbations In One-Carbon Metabolism During Diet-Induced Folate Deficiency, Eric Nonnecke 2010 Iowa State University

Genistein Mediates Perturbations In One-Carbon Metabolism During Diet-Induced Folate Deficiency, Eric Nonnecke

Graduate Theses and Dissertations

Homeostasic balance of one-carbon metabolism is highly dependent upon derivatives of folate and is vital for the prevention of multiple disease states, including vascular disease, birth defects, neurological disorders, and cancer. Homocysteine, a non-protein forming amino acid, accumulates in the absence of 5-methyltetrahydrofolate and represents both a marker for reduced cellular methylation potential and elicitor of pathogenesis (Cattaneo, 1999). In addition to cofactors like folate, vitamin B6, B12, and B2, various bioactive compounds are believed to influence the same cellular processes either directly or indirectly (Strain et al., 2004). The isoflavone genistein exhibits estrogen-like properties and has been implicated in ...


Interaction Of The Baculovirus Occlusion-Derived Virus Envelope Proteins Odv-E56 And Odv-E66 With The Midgut Brush Border Microvilli Of The Tobacco Budworm, Heliothis Virescens (Fabricius), Wendy Olissa Sparks 2010 Iowa State University

Interaction Of The Baculovirus Occlusion-Derived Virus Envelope Proteins Odv-E56 And Odv-E66 With The Midgut Brush Border Microvilli Of The Tobacco Budworm, Heliothis Virescens (Fabricius), Wendy Olissa Sparks

Graduate Theses and Dissertations

Alphabaculoviruses of the family Baculoviridae infect the larvae of the Lepidoptera (moths and butterflies) when the occlusion-derived virus (ODV) released from the occlusion body (OB) binds and fuses to the midgut epithelium. Most alphabaculoviruses readily infect only a few species of caterpillars. The ODV contain more than 30 proteins, twelve of which are conserved across the alphabaculoviruses, including the envelope proteins ODV-E56 and ODV-E66. The mechanism of viral fusion and entry, as well as, the ODV envelope proteins implicated in this process, are unknown. A family of ODV envelope per os infectivity factors (PIFs) has been identified, which includes seven ...


Do The Poor Pay More For Healthy Food? An Empirical Economic Analysis, Patrick Lee Hatzenbuehler 2010 Louisiana State University and Agricultural and Mechanical College

Do The Poor Pay More For Healthy Food? An Empirical Economic Analysis, Patrick Lee Hatzenbuehler

LSU Master's Theses

The economic question this study seeks to answer is why healthier food products are less expensive in some stores than in others and in some neighborhoods than others. The analysis builds upon the precedent of past retail food pricing studies that have been conducted in Southeastern Louisiana and in other parts of the country, by further examining disparities of retail food costs across store formats and neighborhoods with different demographic compositions. It utilizes a comparison of a general market basket of food items used in past studies and a "representative" market basket that is regionally specific to Southeastern Louisiana to ...


Stochastic Trends In Crop Yield Density Estimation, David I. Maradiaga 2010 Louisiana State University and Agricultural and Mechanical College

Stochastic Trends In Crop Yield Density Estimation, David I. Maradiaga

LSU Master's Theses

The search for improved methods of estimating crop yield density functions has been a theme of recurrent research interest in agricultural economics. Crop yield density functions are the statistical instrument that generates probability estimates of yield risk, and risk is an important decision variable in production agriculture. Recent research in crop yield density estimation suggests that yield probability estimates can be sensitive to the way yield data are filtered, and if true, then the search for an “adequate filter” is warranted. Such a quest is pursued in this study. It is proposed that unit-root tests can be used to identify ...


The Model System C. Elegans Demonstrates The Health Benefits Of Legumes And The Potential Benefits Of Legume Consumption, Carla Michele Sandlin 2010 Louisiana State University and Agricultural and Mechanical College

The Model System C. Elegans Demonstrates The Health Benefits Of Legumes And The Potential Benefits Of Legume Consumption, Carla Michele Sandlin

LSU Master's Theses

Legumes are high in protein and are a good source of fiber and folate. They contain beneficial oligosaccharides, plant sterols and phenolics. The purpose of this study was to demonstrate the health benefits of legumes using the model system Caenorhabditis elegans (C. elegans). Nine legumes (black beans, cranberry beans, dark red beans, great northern beans, large lima beans, lentils, light red kidney beans, navy beans and white kidney beans) were tested in the C. elegans model system. The various legume samples were ground using a centrifugal mill to 0.75mm, suspended in water (1% w/v) solution and autoclaved. C ...


Detect Live Salmonella Cells In Produce By Coupling Propidium Monoazide With Loop-Mediated Isothermal Amplification (Pma-Lamp), Siyi Chen 2010 Louisiana State University and Agricultural and Mechanical College

Detect Live Salmonella Cells In Produce By Coupling Propidium Monoazide With Loop-Mediated Isothermal Amplification (Pma-Lamp), Siyi Chen

LSU Master's Theses

Salmonella is a leading cause of foodborne illnesses worldwide. In recent years, an increasing number of Salmonella-related outbreaks in produce has been reported. It is therefore important that the produce industry be equipped with rapid, sensitive, specific detection methods for live Salmonella cells in produce to better ensure the produce safety. In this study, we first designed and optimized a loop-mediated isothermal amplification (LAMP) assay for Salmonella detection by targeting the invasion gene (invA). Then we incorporated a chemical reagent, propidium monoazide (PMA) into the sample preparation step to prevent LAMP amplification of dead Salmonella cells. To our knowledge, this ...


Hybrid Fish Capturing Device "Fcd" For Capturing Live Flounder: Final Report, Jeffrey Hammer 2010 William & Mary

Hybrid Fish Capturing Device "Fcd" For Capturing Live Flounder: Final Report, Jeffrey Hammer

Reports

The purpose of this project was to determine if a device to capture live flounder could be designed and built, to catch effectively. Six FDC's were constructed, two each, of three different funnel designs. The three types of FCD,s were then placed in the water, on april I st 20 I 0, at three different locations. The FCD,s were fished, once per day , for 60 days. The locations were rotated, to give each type of funnel an equal chance. The type of funnels are as follows, # I and 2 were horizontal 2" x 12", # 3 and 4 ...


Cellulosic Ethanol In Louisiana: A Three Part Economic Analysis Of Feedstocks, Pricing Strategies And Location Strategies, Tyler B. Mark 2010 Louisiana State University and Agricultural and Mechanical College

Cellulosic Ethanol In Louisiana: A Three Part Economic Analysis Of Feedstocks, Pricing Strategies And Location Strategies, Tyler B. Mark

LSU Doctoral Dissertations

The development of an efficient biomass supply chain is pivotal for the cellulosic ethanol industry. The Louisiana Sugarcane Belt, and energy cane are the focus of this study. From both the producer and processor perspectives, cost of production, competitiveness of cellulosic ethanol, biomass pricing, changes in crop mix, and the optimal location for cellulosic ethanol processing facilities are the critical factors evaluated. Educating potential energy cane producers on production costs and agronomic practices is the first step in the biomass supply chain. This study finds that for energy cane producers to breakeven, processors need to pay producers at least $30 ...


Analysis Of Media Agenda-Setting Effect On Consumer Confidence In The Safety Of The U.S. Food System Across Consumer Segments, Abhishek Bhagwat Bharad 2010 Louisiana State University and Agricultural and Mechanical College

Analysis Of Media Agenda-Setting Effect On Consumer Confidence In The Safety Of The U.S. Food System Across Consumer Segments, Abhishek Bhagwat Bharad

LSU Master's Theses

Recent food recalls and food scares in the United States have increased consumers’ risk perceptions about food borne illness and decreased their confidence in the safety of the U.S. food supply. Results from a continuous tracking of consumer confidence and media coverage of food safety events over a 67 week period between May 2008 and August 2009 are reported in the study. Factor analysis is performed on consumer characteristic statements to identify seven factors. Factor scores for these seven factors are used as inputs in a consumer segmentation procedure. A two step segmentation approach, hierarchical cluster analysis followed by ...


Adoption Of Breeding Technologies In The U.S. Dairy Industry And Their Influences On Farm Profitability, Aditya Raj Khanal 2010 Louisiana State University and Agricultural and Mechanical College

Adoption Of Breeding Technologies In The U.S. Dairy Industry And Their Influences On Farm Profitability, Aditya Raj Khanal

LSU Master's Theses

Current trends in the U. S. dairy industry show an increase in milk cows per farm and milk production per cow, though the total number of milk cows in the industry is declining. This increase in productivity is attributed to advancements and adoption of modern dairy technologies. Breeding technologies are one of the important components of this structural change. This study analyzed the factors affecting the adoption of modern breeding technologies such as artificial insemination, embryo transplants, and sexed semen, and the impact of these technologies on farm productivity and profitability. Results of a bivariate probit model with selection showed ...


The Role Of Cuticle, Fatty Acids, And Lipid Signaling In Plant Defense, Ye Xia 2010 University of Kentucky

The Role Of Cuticle, Fatty Acids, And Lipid Signaling In Plant Defense, Ye Xia

Theses and Dissertations--Plant Pathology

Systemic acquired resistance (SAR) is initiated upon recognition of specific microbial effectors by cognate plant resistance proteins and immunizes distal tissues of plants against secondary infections. SAR involves the generation of a mobile signal at the site of primary infection, which then translocates to and activates defense responses in the distal tissues via some unknown mechanism(s). This study shows that an ACYL CARRIER PROTEIN 4 (ACP4), GLABRA1 (GL1) and ACYL CARRIER BINDING PROTEINS (ACBP) are required for the processing of the mobile SAR signal in distal tissues of Arabidopsis. Although acp4, gl1 and acbp plants generate the mobile signal ...


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