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First Long-Term, Direct Measurements Of Evapotranspiration And Surface Water Balance In The Nebraska Sandhills, David P. Billesbach, Timothy J. Arkebauer 2012 University of Nebraska–Lincoln

First Long-Term, Direct Measurements Of Evapotranspiration And Surface Water Balance In The Nebraska Sandhills, David P. Billesbach, Timothy J. Arkebauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Nebraska SandHills is a vast grassland ecoregion that also serves as the main recharge zone for the High Plains (Ogallala) aquifer. Despite the national importance of this region in supplying irrigation water and supporting the US cattle industry, there have, until now, been no long-term, direct measurements of the components of the surface water balance. We have addressed this issue by installing energy balance/Bowen ratio (EBBR) flux towers in three key ecosystems. We report here the results of 7 years of measurements and interpret them in terms of annual weather variability. Additionally, these data have allowed us to make …


Accounting For Indirect Land-Use Change In The Life Cycle Assessment Of Biofuel Supply Chains, Susan Tarka Sanchez, Jeremy Woods, Mark Akhurst, Matthew Brander, Michael O'Hare, Terence P. Dawson, Robert Edwards, Adam J. Liska, Rick Malpas 2012 Life Cycle Associates, LLC, Portola Valley, CA

Accounting For Indirect Land-Use Change In The Life Cycle Assessment Of Biofuel Supply Chains, Susan Tarka Sanchez, Jeremy Woods, Mark Akhurst, Matthew Brander, Michael O'Hare, Terence P. Dawson, Robert Edwards, Adam J. Liska, Rick Malpas

Adam Liska Papers

The expansion of land used for crop production causes variable direct and indirect greenhouse gas emissions; and other economic, social and environmental effects. We analyze the use of life cycle analysis (LCA) for estimating the carbon intensity of biofuel production from indirect land-use change (ILUC). Two approaches are critiqued; direct, attributional life cycle analysis (ALCA) and consequential life cycle analysis (CLCA). A proposed hybrid “combined model” of the two approaches for ILUC analysis relies on first defining the system boundary of the resulting full LCA. Choices are then made as to the modeling methodology (economic equilibrium or cause-effect), data inputs, …


Chemical Modification Of Polysaccharides Using Reactive Extrusion, Pratik Bhandari 2012 University of Nebraska-Lincoln

Chemical Modification Of Polysaccharides Using Reactive Extrusion, Pratik Bhandari

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The objective of this dissertation was to study the use of reactive extrusion for the chemical modifications of starch and cellulose. A carboxymethyl derivative of starch and carboxymethyl and acetate derivatives of cellulose were prepared using reactive extrusion.

Carboxymethyl starch with rapid swelling properties in water was prepared using reactive extrusion. This was achieved by controlling the gelatinization and through the use of NaOH by controlling the water/ethanol ratio. The effects of NaOH, H2O, temperature, ethanol, sodium mono chloro acetate, sodium tripolyphosphate, citric acid, epichlorohydrin and extruder screw configuration on the degree of substitution of carboxymethyl starch were …


Methods For Enhancing Expression Of Secondary Cell Wall Cellulose Synthases In Plants, Chandrashekhar P. Joshi 2012 Michigan Technological University

Methods For Enhancing Expression Of Secondary Cell Wall Cellulose Synthases In Plants, Chandrashekhar P. Joshi

Michigan Tech Patents

Described are methods for making transgenic plants capable of expressing secondary cell wall cellulose synthases and methods of enhancing expression of secondary cell wall cellulose synthases in plants. Also described are plants produced by the methods. Plants comprising at least three exogenous polynucleotides encoding secondary cell wall cellulose synthases are also provided.


A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud 2012 American University Washington College of Law, Washington D.C.

A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud

IP Theory

No abstract provided.


Ultrasonic Concentration Of Microorganisms, Samuel J. Mullins 2012 University of Kentcuky

Ultrasonic Concentration Of Microorganisms, Samuel J. Mullins

Theses and Dissertations--Biosystems and Agricultural Engineering

Concentration of microorganisms from a sample volume would increase the limits of detection of samples used for rapid-detection methods. Rapid detection methods are is advantageous for the food industry to rapidly test for bacteria in order release products on a timely basis. Ultrasonic concentration was considered a promising method for manipulation of microorganisms. An ultrasonic chamber consisting of parallel piezoceramic discs with a reticulated polyurethane foam mesh was used to concentrate Saccharomyces cerevisiae yeast and Escherichia coli bacteria. The concentration of yeast was seen to increase by 200% (from 8.0 x 104 cells mL-1 to 2.4 x 10 …


Complete Genome Sequence Of Clostridium Clariflavum Dsm 19732, Javier A. Izquierdo, Lynne Goodwin, Karen W. Davenport, Hazuki Teshima 2012 Dartmouth College

Complete Genome Sequence Of Clostridium Clariflavum Dsm 19732, Javier A. Izquierdo, Lynne Goodwin, Karen W. Davenport, Hazuki Teshima

Dartmouth Scholarship

Clostridium clariflavum is a Cluster III Clostridium within the family Clostridiaceae isolated from thermophilic anaerobic sludge (Shiratori et al, 2009). This species is of interest because of its similarity to the model cellulolytic organism Clostridium thermocellum and for the ability of environmental isolates to break down cellulose and hemicellulose. Here we describe features of the 4,897,678 bp long genome and its annotation, consisting of 4,131 protein-coding and 98 RNA genes, for the type strain DSM 19732.


An Investigation Of Reflective Mulches For Use Over Capillary Mat Systems For Winter-Time Greenhouse Strawberry Production, George E. Meyer, Ellen T. Paparozzi, Elizabeth Walter-Shea, Erin E. Blankenship, Stacy A. Adams 2012 University of Nebraska-Lincoln

An Investigation Of Reflective Mulches For Use Over Capillary Mat Systems For Winter-Time Greenhouse Strawberry Production, George E. Meyer, Ellen T. Paparozzi, Elizabeth Walter-Shea, Erin E. Blankenship, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Photosynthethically active radiation (PAR) is a principle environmental variable used by horticultural specialists, agronomists and ecosystem modelers to characterize the quantity and quality of light conducive to plant growth and development. Spatial distribution of PAR in a greenhouse can be quite variable and diffuse throughout the day time photoperiod, especially at low sun angles in northern regions of the United States. Four colors of reflective plastic mulches (white, red, olive, and black) were evaluated for winter-time strawberry (Fragaria × ananassa Duch.) production based on their reflectance and transmittance properties in a double-polyethylene, plastic-glazed Quonset greenhouse inNebraska. The spectral properties …


A 3-D Computational Fluid Dynamics Model For Forced Air Cooling Of Eggs Placed In Trays, Vikas Kumar, Ai Pheeng Wee, Sohan Birla, Jeyamkondan Subbiah, Harshanardhan Thippareddi 2012 University of Nebraska–Lincoln

A 3-D Computational Fluid Dynamics Model For Forced Air Cooling Of Eggs Placed In Trays, Vikas Kumar, Ai Pheeng Wee, Sohan Birla, Jeyamkondan Subbiah, Harshanardhan Thippareddi

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Shell eggs must be cooled quickly after laying for controlling Salmonella Enteritidis (SE) growth. To fulfill a research need identified by Food Safety and Inspection Service (FSIS), a 3-D Computational Fluid Dynamics (CFD) model was developed to predict the temperature of eggs placed on a tray (6 rows × 5 columns) under forced air cooling. The continuity, momentum, and energy equations were solved along with standard k-ε turbulence model using PHOENICS software. The model was validated by conducting experiments in a wind tunnel at various air temperatures (7–11 °C) and velocities (0.3– 0.7 m/s). Root mean square error for predicting …


The Biological Systems Engineering Program In Nebraska 1895-2011, William Splinter 2012 University of Nebraska-Lincoln

The Biological Systems Engineering Program In Nebraska 1895-2011, William Splinter

Department of Agricultural and Biological Systems Engineering: Faculty Publications

4. Preface: How Mechanization Has Impacted Food Production THE PIONEERS WHO ESTABLISHED THIS DEPARTMENT 8 Oscar Van Pelt Stout 10 Charles Russ Richards 12 J. Brownlee Davidson 14 Leon W. Chase FORMER FACULTY AND THEIR CONTRIBUTIONS 18 Laurence Froyd Seaton 20 Ivan D.Wood 22 Oscar W. Sjogren 23 Chauncey W. Smith 25 Elmer E. Brackett 27 Claud Kedzie Shedd 29 Ruby M. Loper 31 Lester F. Larsen 33 Lloyd W. Hurlbut 36 Rollin Schnieder 39 Howard D. Wittmuss 41 Deon Axthelm 46 Paul. E. Fischbach 48 Stuart O. Nelson 51 Kenneth von Bargen 56 John R. Davis 58 Robert W. …


Evaluation Of The Impact Of Surface Residue Cover On Single And Dual Crop Coefficient For Estimating Soybean Actual Evapotranspiration, Lameck O. Odhiambo, Suat Irmak 2012 University of Nebraska-Lincoln

Evaluation Of The Impact Of Surface Residue Cover On Single And Dual Crop Coefficient For Estimating Soybean Actual Evapotranspiration, Lameck O. Odhiambo, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Single and dual crop coefficient methods are used in conjunction with grass reference evapotranspiration (ETo) to estimate actual crop evapotranspiration (ETc). However, the impact of soil surface residue cover on the accuracy of ETc estimated with these methods is not well understood. The objective of this study is to evaluate and compare the accuracy of the FAO-56 single crop coefficient (single-Kc) and dual crop coefficient (dual-Kc) methods for estimating soybean [Glycine max (L.) Merr.] ETc in a partially residue covered field. The study was conducted …


Using Rapid Geomorphic Assessments To Assess Streambank Stability In Oklahoma Ozark Streams, Derek M. Heeren, Aaron R. Mittelstet, Garey A. Fox, Daniel E. Storm, Abdulsahib T. Al-Madhhachi, Taber L. Midgley, Ashley F. Stringer, Kevin B. Stunkel, Ron D. Tejral 2012 University of Nebraska-Lincoln

Using Rapid Geomorphic Assessments To Assess Streambank Stability In Oklahoma Ozark Streams, Derek M. Heeren, Aaron R. Mittelstet, Garey A. Fox, Daniel E. Storm, Abdulsahib T. Al-Madhhachi, Taber L. Midgley, Ashley F. Stringer, Kevin B. Stunkel, Ron D. Tejral

Department of Agricultural and Biological Systems Engineering: Faculty Publications

High streambank erosion and failure rates on streams in the Ozark ecoregion of Oklahoma may be attributed to land use change and degradation of riparian areas. Numerous benefits may be achieved from streambank stabilization, but methods are needed to determine the most critical reaches for investing limited funds. Rapid geomorphic assessments (RGAs) have been used to aid in prioritizing stream reaches. This research (1) applied an existing RGA, the channel stability index (CSI), on several reaches along the Barren Fork Creek and Spavinaw Creek, and (2) modified the existing RGA to create an ecoregion-specific RGA called the Oklahoma Ozark streambank …


Climate Change Impacts On Streamflow, Water Quality, And Best Management Practices For The Shell And Logan Creek Watersheds In Nebraska, M. W. Van Liew, S. Feng, T. B. Pathak 2012 University of Nebraska-Lincoln

Climate Change Impacts On Streamflow, Water Quality, And Best Management Practices For The Shell And Logan Creek Watersheds In Nebraska, M. W. Van Liew, S. Feng, T. B. Pathak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Improvements in the management of water, sediment, and nutrients under future climatic conditions are needed to ensure increased crop and livestock production to meet greater global needs and the future availability of water for competing demands and protection against adverse water quality impairments. This study determined the impacts of future climate change scenarios on streamflow, water quality, and best management practices (BMPs) for two watersheds in Nebraska, USA. The Soil and Water Assessment Tool (SWAT) was employed to simulate streamflow, sediment, total nitrogen (N) and total phosphorus (P) from the Shell Creek Watershed near Columbus, Nebraska and the Logan Creek …


Carbon, Water, And Heat Flux Responses To Experimental Burning And Drought In A Tallgrass Prairie, Marc L. Fischer, M S. Torn, David P. Billesbach, Geoffrey Doyle, Brian Northup, Sebastien C. Biraud 2012 Lawrence Berkeley National Laboratory

Carbon, Water, And Heat Flux Responses To Experimental Burning And Drought In A Tallgrass Prairie, Marc L. Fischer, M S. Torn, David P. Billesbach, Geoffrey Doyle, Brian Northup, Sebastien C. Biraud

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Drought and fire are common disturbances to grassland ecosystems. We report two years of eddy covariance ecosystem–atmosphere fluxes and biometric variables measured in nearby burned and unburned pastures in the US Southern Great Plains. Over the course of the experiment, annual precipitation (∼600 mm yr−1) was lower than the long term mean (∼860 mm yr−1). Soil moisture decreased from productive conditions in March 2005 dry, unproductive conditions during the growing season starting in March 2006. Just prior to the burn in early March 2005, burned and unburned pastures contained 520 ± 60 and 360 ± 40 …


Global Estimation Of Evapotranspiration Using A Leaf Area Index-Based Surface Energy And Water Balance Model, H. Yan, S.Q. Wang, David P. Billesbach, Walter Oechel, J.H. Zhang, Tilden Meyers, TA. Martin, Roser Matamala, Dennis D. Baldocchi, G. Bohrer, D. Dragoni, R. Scott 2012 China Meteorological Administration

Global Estimation Of Evapotranspiration Using A Leaf Area Index-Based Surface Energy And Water Balance Model, H. Yan, S.Q. Wang, David P. Billesbach, Walter Oechel, J.H. Zhang, Tilden Meyers, Ta. Martin, Roser Matamala, Dennis D. Baldocchi, G. Bohrer, D. Dragoni, R. Scott

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Studies of global hydrologic cycles, carbon cycles and climate change are greatly facilitated when global estimates of evapotranspiration (E) are available. We have developed an air-relative-humidity-based two-source (ARTS) E model that simulates the surface energy balance, soil water balance, and environmental constraints on E. It uses remotely sensed leaf area index (Lai) and surface meteorological data to estimate E by: 1) introducing a simple biophysical model for canopy conductance (Gc), defined as a constant maximum stomatal conductance gsmax of 12.2mm s−1multiplied by air relative humidity (Rh …


Energy Issues Affecting Corn/Soybean Systems: Challenges For Sustainable Production, Douglas L. Karlen, David Archer, Adam Liska, Seth Meyer 2012 USDA-ARS, Ames, Iowa

Energy Issues Affecting Corn/Soybean Systems: Challenges For Sustainable Production, Douglas L. Karlen, David Archer, Adam Liska, Seth Meyer

Adam Liska Papers

Quantifying energy issues associated with agricultural systems, even for a two-crop corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) rotation, is not a simple task. It becomes even more complicated if the goal is to include all aspects of sustainability (i.e., economic, environmental, and social). This Issue Paper examines energy issues associated with and affecting corn/soybean rotations by first defining the size of the system from both a U.S. and global perspective and then establishing boundaries based on the Farm Bill definition of sustainability. This structured approach is essential to help quantify energy issues within corn/soybean …


Subsurface Phosphorus Transport And Scale Dependent Phosphorus Leaching In Alluvial Floodplains, Derek Michael Heeren 2012 Oklahoma State University - Main Campus

Subsurface Phosphorus Transport And Scale Dependent Phosphorus Leaching In Alluvial Floodplains, Derek Michael Heeren

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Increased nutrient loads have resulted in several adverse impacts on surface water quality, including excessive algal growth, fish kills, and drinking water taste and odor issues across the United States and especially in the Ozark ecoregion of northeastern Oklahoma and northwestern Arkansas. Nitrogen is a concern, but phosphorus (P) is generally considered the limiting nutrient in most surface water systems. Scientists and engineers need to identify critical nutrient source areas and transport mechanisms within a catchment in order to cost effectively protect and enhance drinking water systems, recreation activities, and aquatic ecosystems. While surface runoff is considered to be the …


Computational Analysis Of Hybrid Norwood Circulation With Distal Aortic Arch Obstruction And Reverse Blalock-Taussig Shunt, Andres Ceballos, I. Ricardo Argueta-Morales, Eduardo Divo, Ruben Osorio, Christopher A. Caldarone, Alain J. Kassab, William M. DeCampli 2012 University of Central Florida

Computational Analysis Of Hybrid Norwood Circulation With Distal Aortic Arch Obstruction And Reverse Blalock-Taussig Shunt, Andres Ceballos, I. Ricardo Argueta-Morales, Eduardo Divo, Ruben Osorio, Christopher A. Caldarone, Alain J. Kassab, William M. Decampli

Mechanical Engineering - Daytona Beach

BACKGROUND: The hemodynamics characteristics of the hybrid Norwood (HN) procedure differ from those of the conventional Norwood and are not fully understood. We present a multi-scale model of HN circulation to understand local hemodynamics and effects of aortic arch stenosis and a reverse Blalock-Taussig shunt (RBTS) on coronary and carotid perfusion. METHODS: Four 3-dimensional models of four HN anatomic variants were developed, with and without 90% distal preductal arch stenosis and with and without a 4-mm RBTS. A lumped parameter model of the circulation was coupled to a local 3-dimensional computational fluid dynamics model. Outputs from the lumped parameter model …


Computational Fluid Dynamics In Congenital Heart Disease, William M. DeCampli, I. Ricardo Argueta-Morales, Eduardo Divo, Alain J. Kassab 2012 Arnold Palmer Hospital for Children

Computational Fluid Dynamics In Congenital Heart Disease, William M. Decampli, I. Ricardo Argueta-Morales, Eduardo Divo, Alain J. Kassab

Mechanical Engineering - Daytona Beach

Computational fluid dynamics has been applied to the design, refinement, and assessment of surgical procedures and medical devices. This tool calculates flow patterns and pressure changes within a virtual model of the cardiovascular system. In the field of paediatric cardiac surgery, computational fluid dynamics is being used to elucidate the optimal approach to staged reconstruction of specific defects and study the haemodynamics of the resulting anatomical configurations after reconstructive or palliative surgery. In this paper, we review the techniques and principal findings of computational fluid dynamics studies as applied to a few representative forms of congenital heart disease.


Enhanced Microbial Utilization Of Recalcitrant Cellulose By An Ex Vivo Cellulosome-Microbe Complex, Chun You, Xiao-Zhou Zhang, Noppadon Sathitsuksanoh, Lee R. Lynd 2011 Virginia Polytechnic Institute and State University

Enhanced Microbial Utilization Of Recalcitrant Cellulose By An Ex Vivo Cellulosome-Microbe Complex, Chun You, Xiao-Zhou Zhang, Noppadon Sathitsuksanoh, Lee R. Lynd

Dartmouth Scholarship

A cellulosome-microbe complex was assembled ex vivo on the surface of Bacillus subtilis displaying a miniscaffoldin that can bind with three dockerin-containing cellulase components: the endoglucanase Cel5, the processive endoglucanase Cel9, and the cellobiohydrolase Cel48. The hydrolysis performances of the synthetic cellulosome bound to living cells, the synthetic cellulosome, a noncomplexed cellulase mixture with the same catalytic components, and a commercial fungal enzyme mixture were investigated on low-accessibility recalcitrant Avicel and high accessibility regenerated amorphous cellulose (RAC). The cellbound cellulosome exhibited 4.5- and 2.3-fold-higher hydrolysis ability than cell-free cellulosome on Avicel and RAC, respectively. The cellulosome-microbe synergy was not completely …


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