Life Sciences Commons^™

Towards A Unification Of Supercomputing, Molecular Dynamics Simulation And Experimental Neutron And X-Ray Scattering Techniques, Benjamin Lindner

Doctoral Dissertations

Molecular dynamics simulation has become an essential tool for scientific discovery and investigation. The ability to evaluate every atomic coordinate for each time instant sets it apart from other methodologies, which can only access experimental observables as an outcome of the atomic coordinates. Here, the utility of molecular dynamics is illustrated by investigating the structure and dynamics of fundamental models of cellulose fibers. For that, a highly parallel code has been developed to compute static and dynamical scattering functions efficiently on modern supercomputing architectures. Using state of the art supercomputing facilities, molecular dynamics code and parallelization strategies, this work also …

Environmental Impacts Of Stover Removal In The Corn Belt, Alicia English, Wallace E. Tyner, Juan Sesmero, Phillip Owens, David J. Muth Jr.

David J. Muth

When considering the market for biomass from corn stover resources erosion and soil quality issues are important to consider. Removal of stover can be beneficial in some areas, especially when coordinated with other conservation practices, such as vegetative barrier strips and cover crops. However, benefits are highly dependent on several factors, namely if farmers see costs and benefits associated with erosion and the tradeoffs with the removal of biomass. This paper uses results from an integrated RUSLE2/WEPS model to incorporate six different regime choices, covering management, harvest and conservation, into a simple profit maximization model to show these tradeoffs.

Classification Of Multi-Domain Glycoside Hydrolases To Aid In The Enzymatic Production Of Biofuels From Biomass, Emi Leonard, Gregg Beckham, Deanne Sammond, Michael Crowley

STAR Program Research Presentations

Biomass conversion to renewable biofuels provides an alternative to conventional fossil-fuel based transportation fuels and a means to reduce dependence on foreign oil. However, plant cell walls have evolved to be quite resistant to enzymatic deconstruction, a phenomenon generally termed biomass recalcitrance. As enzymes represent a substantial cost in biofuels production, there is significant impetus to understand and improve their efficiency in converting cell wall carbohydrates to fermentable sugars. Much research has been conducted on single "free" enzymes with one catalytic unit per protein and on the much larger, complexed "cellulosomes" with many tens of catalytic units per protein, but …

Effects Of Precipitation Increase On Soil Respiration: A Three-Year Field Experiment In Subtropical Forests In China, Qi Deng, Dafeng Hui, Deqiang Zhang, Guoyi Zhou, Juxiu Liu, Shizhong Liu, Guowei Chu, Jiong Li

Biology Faculty Research

Background

The aim of this study was to determine response patterns and mechanisms of soil respiration to precipitation increases in subtropical regions.

Methodology/Principal Findings

Field plots in three typical forests [i.e. pine forest (PF), broadleaf forest (BF), and pine and broadleaf mixed forest (MF)] in subtropical China were exposed under either Double Precipitation (DP) treatment or Ambient Precipitation (AP). Soil respiration, soil temperature, soil moisture, soil microbial biomass and fine root biomass were measured over three years. We tested whether precipitation treatments influenced the relationship of soil respiration rate (R) with soil temperature (T) and soil …

Grass And Canada Goldenrod (Solidago Canadensis) Competition And Implications For Management In The Northern Tallgrass Prairie, Alexander J. Smart, Gary E. Larson, Peter J. Bauman

The Prairie Naturalist

Canada goldenrod (Solidago canadensis L.) is a native perennial forb that can form dense clonal patches and become weedy in pastures of the Northern Tallgrass Prairie Ecoregion. Our objectives were to determine 1) the competitive effects between Canada goldenrod and grass, 2) the relationship between Canada goldenrod stem density and grass biomass, and 3) the distribution of Canada goldenrod stem density at the pasture scale. We used regression analysis to develop a relationship between Canada goldenrod stem density and grass biomass. Additionally, we estimated the frequency distribution of Canada goldenrod stem density categories using three evenly distributed 100 × 100-m …

Farm-Scale Production Cost Of Switchgrass For Biomass, Richard Perrin, Kenneth P. Vogel, Marty Schmer, Robert B. Mitchell

Richard K Perrin

The economic potential of cellulosic biomass from switchgrass has heretofore been evaluated using estimates of farm costs based on extrapolation from experimental data and budget estimates. The objective of the project reported here was to estimate the cost of production that would be experienced by farmers on commercial production situations. Switchgrass was produced as a biomass crop on commercial-scale fields by ten contracting farmers located from northern North Dakota to southern Nebraska. Results showed a wide range of yields and costs across the five production years and ten sites, with an overall average cost of $65.86 Mg^-1 of biomass …

Biomass Assisted Synthesis Of Antibacterial Gold Nanoparticles And Commentary On Its Future Potential And Applications In Medicine, Chad Willis

Mahurin Honors College Capstone Experience/Thesis Projects

Xylose is a natural monosaccharide found in biomass such as straw, pecan shells, cottonseed hulls, and corncobs. Using this monosaccharide, we report the green synthesis and characterization of biocompatible, biodegradable xylose encapsulated gold nanoparticles (Xyl-GNPs) with potential antibacterial activity. GNPs were synthesized using the bioreduction property of xylose on the chloroaurate anions in an aqueous solution at room temperature and at atmospheric pressure. The characterization of synthesized GNPs was examined by UV-vis spectroscopy; transmission electron microscopy (TEM), energy-dispersive x-ray spectroscopy (EDS) and fourier transform infrared spectroscopy (FTIR). Results indicate that the particles were stable; near spherical in shape with an …

Metabolic And Gene Expression Changes Triggered By Nitrogen Deprivation In The Photoautotrophically Grown Microalgae Chlamydomonas Reinhardtii And Coccomyxa Sp. C-169, Joseph Msanne, Di Xu, Anji Reddy Konda, J. Armando Casas-Mollano, Tala Awada, Edgar B. Cahoon, Heriberto Cerutti

Center for Plant Science Innovation: Faculty and Staff Publications

Microalgae are emerging as suitable feedstocks for renewable biofuel production. Characterizing the metabolic pathways involved in the biosynthesis of energy-rich compounds, such as lipids and carbohydrates, and the environmental factors influencing their accumulation is necessary to realize the full potential of these organisms as energy resources. The model green alga Chlamydomonas reinhardtii accumulates significant amounts of triacylglycerols (TAGs) under nitrogen starvation or salt stress in medium containing acetate. However, since cultivation of microalgae for biofuel production may need to rely on sunlight as the main source of energy for biomass synthesis, metabolic and gene expression changes occurring in Chlamydomonas and …

Private Landowner Intent To Supply Forest Biomass For Energy In Kentucky, Zachary John Leitch

Theses and Dissertations--Forestry and Natural Resources

The Commonwealth of Kentucky is taking steps to expand bioenergy production in response to federal policy initiatives as well as environmental and energy security concerns. The success of this industry will be impacted by the supply of feedstock available from private individuals who own a majority (78%) of forest resources in the state. Despite a developing body of bioenergy research, little is known concerning the social availability of forest biomass for energy production. This study measures intent to harvest energy wood among family forest owners using a mail-­‐based survey and tests the effect of educational materials provided to participants. The …

The Effect Of Row Spacing And Seeding Rate On Biomass Production And Plant Stand Characteristics Of Non-Irrigated Photoperiod-Sensitive Sorghum (Sorghum Bicolor (L.) Moench), John L. Snider, Randy L. Raper, Eric B. Schwab

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

To evaluate row spacing and seeding rate effects on yield and plant stand characteristics of high-biomass sorghum, a photoperiod-sensitive cultivar was sown at three different row spacings (76, 38, and 19 cm) and seeding rates (218,000, 306,000, and 393,000 seeds ha⁻¹ for one site-year and 116,000, 204,000, and 291,000 seeds ha⁻¹ for three site-years) from 2009 to 2010 in Alabama and Arkansas, USA. Measurements included above-ground dry matter production, plant height, stem density, and stem diameter. Narrower row spacing (i.e. 19 cm) produced the highest biomass for all site-years. Increasing seeding rate did not affect yield for three …

Drift Algae, An Invasive Snail And Elevated Temperature Reduce Ecological Performance Of A Warm-Temperate Seagrass, Through Additive Effects, H Hoffle, Thomas Wernberg, Mads Thomsen, M Holmer

Research outputs 2012

Seagrasses are under pressure from multiple concurrent threats, including rising temperatures, invasive species and nutrient-driven algal accumulations. We quantified the abundance of drift algae and the invasive snail Batillaria australis in 3 Halophila ovalis seagrass beds in the Swan River Estuary (Perth, Western Australia), and tested in an aquarium experiment for interactive effects of temperature (21 vs. 27°C), cover of drift algae Chaetomorpha linum (0 vs. 1.4 kg fresh wt m -2) and presence (0 vs. 120 snails m -2) of B. australis on the ecological performance of H. ovalis. The survey showed that drift algae varied considerably between sites …

Two-Stage Sampling To Estimate Individual Tree Biomass, Ramazan Özçeli̇k, Tuncay Eraslan

Turkish Journal of Agriculture and Forestry

The accurate estimation of tree biomass is crucial for the efficient management of forest resources. In this study, we used a subsampling method for unbiased estimates of above-ground tree biomass. The method consists of 2 stages: the first stage consists of randomized branch sampling (RBS) and the second stage uses importance sampling (IS). RBS is used to select a path from the butt of an object branch to a terminal segment. IS is used for selecting a disk that produces unbiased estimates of the fresh biomass of tree. In this study, the subsampling method was tested on 14 black pine …

Effect Of Cell-Conditioned Media On Biomass Production Of Leishmania Parasites, Melahat Bagirova, Rabi̇a Çakir Koç, Adi̇l Allahverdi̇yev, Meli̇ke Ersöz

Turkish Journal of Biology

A large amount of parasite biomass production necessitates a higher volume of culture media, and this further increases the overall cost. For this reason, novel and alternative culture supplementary materials have been continuously investigated. The aim of this study was therefore to evaluate the effect of cell-conditioned media, collected as waste material during routine cell culture, on the growth and development of Leishmania parasites in vitro. In this study, for the first time, we show that cell-conditioned medium obtained from MCF-7 culture increased the growth of Leishmania parasites in vitro. These results show that the metabolites that are present in …

Seed Reduction In Prairie Cordgrass, Spartina Pectinata Link., By The Floret-Feeding Caterpillar Aethes Spartinana (Barnes And Mcdunnough), Jarrad R. Prasifka, D. K. Lee, Jeffrey Bradshaw, Allen S. Parrish, Michael E. Gray

Panhandle Research and Extension Center

Insect damage to prairie cordgrass, Spartina pectinata Link., is conspicuously high in Illinois, where attempts to collect native seed show the majority of spikelets damaged with small holes. Dissection of spikes during summer reveals minute caterpillars boring though glumes and feeding on florets inside. In 2009–2010, panicles of prairie cordgrass from across its native range were used to estimate the percentage of insect-related damage and losses to seed production. Collections of caterpillars from panicles and stems were used to identify one floret-feeding species, estimate its distribution in the central USA, and assess its feeding patterns within spikes. Insect feeding damaged …

Economic Modeling & Optimization Of A Region Specific Multi-Feedstock Biorefinery Supply Chain, William H. Faulkner

Theses and Dissertations--Manufacturing Systems Engineering

The objective of this thesis is to include strategic and tactical level decisions into the biorefinery supply chain design for a specific region while comparing multiple conversion technologies and biomass feedstocks. The allocation of biomass feedstocks, products, and the respective supply chain configuration locations are determined while ensuring the regions monthly biomass availability and product market demand constraints are met. This research considers all actions required to bring the bio-based products to market from harvesting, storing, and processing the biomass to market distribution. Two different conversion technologies are chosen for comparison: one advanced conversion technology and one conventional technology. Potential …

Season- And Locality-Related Changes In The Diet Of Asiatic Jackal (Canis Aureus) In Potohar, Pakistan, Muhammad Sajid Nadeem, Ruqqya Naz, Syed Israr Shah, Mirza Azhar Beg, Amjad Rashid Kayani, Muhammad Mushtaq, Tariq Mahmood

Turkish Journal of Zoology

Feeding habits of the Asiatic jackal were studied through 98 scats collected between January 2009 and March 2010 from different sites in Potohar, Pakistan. The overall frequency of occurrence of plant items was 54.0%; the animal prey item frequency was 46.2%. Among the plant foods, Ziziphus was eaten year round, whereas wild olive, grasses, and wheat grains were the chief components of the diet during all seasons except summer. Among the animal food items, livestock carcasses were consumed year round; the highest consumption was observed during the summer and autumn seasons and the lowest in winter. Small mammals, particularly rodents, …

Place-Based Approaches To Alternative Energy: The Potential For Forest And Grass Biomass For Aroostook County, Jason Johnston, Soraya Cardenas

Maine Policy Review

Teams at the University of Maine Presque Isle and the University of Maine at Forth Kent are engaged in evaluating the potential for forest and grass biomass energy in Aroostook County, funded through Maine’s Sustainability Solutions Initiative. The article discusses how this potential is being evaluated and the possible ways in which expanding grass and wood biomass might benefit farmers and residents of The County. It suggests that using some of Maine’s farmland for fuel might be sustainable with appropriate management and with consideration for potential environmental and socioeconomic drawbacks