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Grain Yield, Crop And Basal Evapotranspiration, Production Functions And Water Productivity Response Of Drought-Tolerant And Non-Drought-Tolerant Maize Hybrids Under Different Irrigation Levels, And Population Densities: Part I. In Western Nebraska's Semi-Arid Environments, Ali T. Mohammed, Suat Irmak, William Kranz, Simon van Donk, C. Dean Yonts 2019 University of Nebraska–Lincoln

Grain Yield, Crop And Basal Evapotranspiration, Production Functions And Water Productivity Response Of Drought-Tolerant And Non-Drought-Tolerant Maize Hybrids Under Different Irrigation Levels, And Population Densities: Part I. In Western Nebraska's Semi-Arid Environments, Ali T. Mohammed, Suat Irmak, William Kranz, Simon Van Donk, C. Dean Yonts

Department of Biological Systems Engineering: Papers and Publications

Grain yield, crop evapotranspiration (ETc), basal evapotranspiration (ETb), ETc-yield production functions (ETYPF), and crop water use efficiency (CWUE) response of three drought-tolerant (DT) and one non-drought-tolerant (NDT) maize (Zea mays L.) hybrids to two plant population densities (PPDs) [84,000 plants ha-1 (high PPD) and 59,300 plants ha-1 (low PPD)] and three irrigation levels were researched at two semi-arid locations: North Platte (WCREC) and Scottsbluff (MAL), Nebraska, in 2010, 2011, and 2012. The irrigation levels were fully irrigated (FIT), early cutoff (ECOT), and rainfed (RFT). Precipitation in 2010 was above average, 2011 was a normal year, and 2012 was one of …


Grain Yield, Crop And Basal Evapotranspiration, Production Functions And Water Productivity Response Of Drought-Tolerant And Non-Drought-Tolerant Maize Hybrids Under Different Irrigation Levels, Population Densities And Environments: Part Ii. In South-Central And Northeast Nebraska's Transition Zone And Sub-Humid Environments, Suat Irmak, Ali T. Mohammed, William Kranz 2019 The Pennsylvania State University

Grain Yield, Crop And Basal Evapotranspiration, Production Functions And Water Productivity Response Of Drought-Tolerant And Non-Drought-Tolerant Maize Hybrids Under Different Irrigation Levels, Population Densities And Environments: Part Ii. In South-Central And Northeast Nebraska's Transition Zone And Sub-Humid Environments, Suat Irmak, Ali T. Mohammed, William Kranz

Department of Biological Systems Engineering: Papers and Publications

Information and data on newer drought-tolerant maize hybrid response to water in different climates are extremely scarce. This research quantified the performance of non-drought-tolerant (NDT) (H1) and drought-tolerant (DT) (H2, H3, and H4) maize (Zea mays L.) hybrids response to grain yield, crop evapotranspiration (ETc), basal evapotranspiration (ETb), ETc-yield production functions (ETYPF), and crop water use efficiency (CWUE) at three irrigation levels and two plant population densities (PPDs) at two locations (transition zone between sub-humid and semiarid climates at Clay Center (SCAL), Nebraska, in 2010 and 2012; and in a sub-humid climate at Concord (HAL), Nebraska, in 2010, 2011, and …


Fuzzy Control System For Variable Rate Irrigation Using Remote Sensing, Willians Ribeiro Mendes, Fábio Meneghetti U. Araújo, Ritaban Dutta, Derek M. Heeren 2019 IFMT, Mato Grosso/MT, Brazil

Fuzzy Control System For Variable Rate Irrigation Using Remote Sensing, Willians Ribeiro Mendes, Fábio Meneghetti U. Araújo, Ritaban Dutta, Derek M. Heeren

Department of Biological Systems Engineering: Papers and Publications

Variable rate irrigation (VRI) is the capacity to spatially vary the depth of water application in a field to handle different types of soils, crops, and other conditions. Precise management zones must be developed to efficiently apply variable rate technologies. However, there is no universal method to determine management zones. Using speed control maps for the central pivot is one option. Thus, this study aims to develop an intelligent fuzzy inference system based on precision irrigation knowledge, i.e., a system that can create prescriptive maps to control the rotation speed of the central pivot. Satellite images are used in this …


Design Of Plant Protection Uav Variable Spray System Based On Neural Networks, Sheng Wen, Quanyong Zhang, Xuanchun Yin, Yubin Lan, Jiantao Zhang, Yufeng Ge 2019 South China Agricultural University

Design Of Plant Protection Uav Variable Spray System Based On Neural Networks, Sheng Wen, Quanyong Zhang, Xuanchun Yin, Yubin Lan, Jiantao Zhang, Yufeng Ge

Department of Biological Systems Engineering: Papers and Publications

Recently, unmanned aerial vehicles (UAVs) have rapidly emerged as a new technology in the fields of plant protection and pest control in China. Based on existing variable spray research, a plant protection UAV variable spray system integrating neural network based decision making is designed. Using the existing data on plant protection UAV operations, combined with artificial neural network (ANN) technology, an error back propagation (BP) neural network model between the factors affecting droplet deposition is trained. The factors affecting droplet deposition include ambient temperature, ambient humidity, wind speed, flight speed, flight altitude, propeller pitch, nozzles pitch and prescription value. Subsequently, …


Free Polyethylenimine Enhances Substrate-Mediated Gene Delivery On Titanium Substrates Modified With Rgd-Functionalized Poly(Acrylic Acid) Brushes, Amy Mantz, Alice Rosenthal, Eric Farris, Tyler Kozisek, Eva Bittrich, Saghar Nazari, Eva Schubert, Mathias Schubert, Manfred Stamm, Petra Uhlmann, Angela K. Pannier 2019 University of Nebraska-Lincoln

Free Polyethylenimine Enhances Substrate-Mediated Gene Delivery On Titanium Substrates Modified With Rgd-Functionalized Poly(Acrylic Acid) Brushes, Amy Mantz, Alice Rosenthal, Eric Farris, Tyler Kozisek, Eva Bittrich, Saghar Nazari, Eva Schubert, Mathias Schubert, Manfred Stamm, Petra Uhlmann, Angela K. Pannier

Department of Biological Systems Engineering: Papers and Publications

Substrate mediated gene delivery (SMD) is a method of immobilizing DNA complexes to a substrate via covalent attachment or nonspecific adsorption, which allows for increased transgene expression with less DNA compared to traditional bolus delivery. It may also increase cells receptivity to transfection via cell-material interactions. Substrate modifications with poly(acrylic) acid (PAA) brushes may improve SMD by enhancing substrate interactions with DNA complexes via tailored surface chemistry and increasing cellular adhesion via moieties covalently bound to the brushes. Previously, we described a simple method to graft PAA brushes to Ti and further demonstrated conjugation of cell adhesion peptides (i.e., RGD) …


Genetic Diversity And Population Structure Of A Camelina Sativa Spring Panel, Zinan Luo, Jordan Brock, John M. Dyer, Toni Kutchan, Daniel P. Schachtman, Megan Augustin, Yufeng Ge, Noah Fahlgren, Hussein Abdel-Haleem 2019 USDA, Agricultural Research Service

Genetic Diversity And Population Structure Of A Camelina Sativa Spring Panel, Zinan Luo, Jordan Brock, John M. Dyer, Toni Kutchan, Daniel P. Schachtman, Megan Augustin, Yufeng Ge, Noah Fahlgren, Hussein Abdel-Haleem

Department of Biological Systems Engineering: Papers and Publications

There is a need to explore renewable alternatives (e.g., biofuels) that can produce energy sources to help reduce the reliance on fossil oils. In addition, the consumption of fossil oils adversely affects the environment and human health via the generation of waste water, greenhouse gases, and waste solids. Camelina sativa, originated from southeastern Europe and southwestern Asia, is being re-embraced as an industrial oilseed crop due to its high seed oil content (36–47%) and high unsaturated fatty acid composition (>90%), which are suitable for jet fuel, biodiesel, high-value lubricants and animal feed. C. sativa’s agronomic advantages include …


Nucleic Acid Delivery To Mesenchymal Stem Cells: A Review Of Nonviral Methods And Applications, Andrew Hamann, Albert Nguyen, Angela K. Pannier 2019 University of Nebraska-Lincoln

Nucleic Acid Delivery To Mesenchymal Stem Cells: A Review Of Nonviral Methods And Applications, Andrew Hamann, Albert Nguyen, Angela K. Pannier

Department of Biological Systems Engineering: Papers and Publications

Background: Mesenchymal stem cells (MSCs) are multipotent stem cells that can be isolated and expanded from many tissues, and are being investigated for use in cell therapies. Though MSC therapies have demonstrated some success, none have been FDA approved for clinical use. MSCs lose stemness ex vivo, decreasing therapeutic potential, and face additional barriers in vivo, decreasing therapeutic efficacy. Culture optimization and genetic modification of MSCs can overcome these barriers. Viral transduction is efficient, but limited by safety concerns related to mutagenicity of integrating viral vectors and potential immunogenicity of viral antigens. Nonviral delivery methods are safer, though limited …


Economic Analysis Of Deficit Irrigation In Sugarcane Farming: Nchalo Estate, Chikwawa District, Malawi, Mavuto M. Banda, Derek M. Heeren, Derrel Martin, Francisco Munoz-Arriola, László G. Hayde 2019 University of Nebraska-Lincoln

Economic Analysis Of Deficit Irrigation In Sugarcane Farming: Nchalo Estate, Chikwawa District, Malawi, Mavuto M. Banda, Derek M. Heeren, Derrel Martin, Francisco Munoz-Arriola, László G. Hayde

Department of Biological Systems Engineering: Papers and Publications

Sustenance of the growing world population calls for increased agricultural production. However, this will have to be done while forecasts of water withdrawals on a global scale predict sharp increases in future demand to meet human needs. The inadequacy of irrigation water supplies has led to the need to consider deficit irrigation (DI) as a water saving strategy. DI is a deliberate under-application of water to growing crops.

In this study we carried out an economic analysis of DI in sugarcane farming with an aim of developing an understanding of the economic impact of various irrigation water management strategies. The …


Actual Evapotranspiration And Crop Coefficients Of Irrigated Lowland Rice (Oryza Sativa L.) Under Semiarid Climate, Koffi Djaman, Daran R. Rudnick, Yonnelle D. Moukoumbi, Abdoulaye Sow, Suat Irmak 2019 AfricaRice

Actual Evapotranspiration And Crop Coefficients Of Irrigated Lowland Rice (Oryza Sativa L.) Under Semiarid Climate, Koffi Djaman, Daran R. Rudnick, Yonnelle D. Moukoumbi, Abdoulaye Sow, Suat Irmak

Department of Biological Systems Engineering: Papers and Publications

Lowland irrigated rice is the predominant crop produced in the Senegal River Valley characterized by very low annual rainfall, high temperatures, and low relative humidity. The Senegal River is shared by Senegal, Mali, Mauritania, and Guinea, and serves as the main source of irrigation water for the adopted double rice cropping system. Developing appropriate resource management strategies might be the key factor for the sustainability of rice production in the region. This study aims to estimate rice seasonal evapotranspiration (ETa), irrigation water requirement, and to develop rice growth stage specific crop coefficients (Kc) to improve rice water productivity. Field experiments …


The Development Of The Infews-Er: A Virtual Resource Center For Transdisciplinary Graduate Student Training At The Nexus Of Food, Energy, And Water, Luis F. Rodriguez, Anna-Maria Marshall, Dan Cotton, Richard K. Koelsch, Jacek Koziel, Deanne Meyer, Dan Steward, Jill Heemstra, Anand Padmanabahn, John Classen, Nathan J. Meyer, Benjamin L. Ruddell, Sean M. Ryan, Ximing Cai, Emad Habib, Peter D. Saundry 2019 University of Illinois at Urbana-Champaign

The Development Of The Infews-Er: A Virtual Resource Center For Transdisciplinary Graduate Student Training At The Nexus Of Food, Energy, And Water, Luis F. Rodriguez, Anna-Maria Marshall, Dan Cotton, Richard K. Koelsch, Jacek Koziel, Deanne Meyer, Dan Steward, Jill Heemstra, Anand Padmanabahn, John Classen, Nathan J. Meyer, Benjamin L. Ruddell, Sean M. Ryan, Ximing Cai, Emad Habib, Peter D. Saundry

Department of Biological Systems Engineering: Papers and Publications

Problems at the nexus of Food, Energy and Water Systems (FEWS) are among the most complex challenges we face. Spanning simple to complex temporal, geographic, social, and political framings, the questions raised at this nexus require multidisciplinary if not transdisciplinary approaches. Answers to these questions must draw from engineering, the physical and biological sciences, and the social sciences. Practical solutions depend upon a wide community of stakeholders, including industry, policymakers, and the general public. Yet there are many obstacles to working in a transdisciplinary environment: unfamiliar concepts, specialized terminology, and countless “blind” spots. Graduate education occurs in disciplinary ‘silos’, often …


Water Effects On Optical Canopy Sensing For Late-Season Site-Specific Nitrogen Management Of Maize, Tsz Him Lo, Daran Rudnick, Brian Krienke, D. M. Heeren, Yufeng Ge, Tim M. Shaver 2019 University of Nebraska-Lincoln

Water Effects On Optical Canopy Sensing For Late-Season Site-Specific Nitrogen Management Of Maize, Tsz Him Lo, Daran Rudnick, Brian Krienke, D. M. Heeren, Yufeng Ge, Tim M. Shaver

Department of Biological Systems Engineering: Papers and Publications

The interpretation of optical canopy sensor readings for determining optimal rates of late-season site-specific nitrogen application to corn (Zea mays L.) can be complicated by spatially variable water sufficiency, which can also affect canopy size and/or pigmentation. In 2017 and 2018, corn following corn and corn following soybeans were subjected to irrigation×nitrogen fertilizer treatments in west central Nebraska, USA, to induce variable water sufficiency and variable nitrogen sufficiency. The vegetation index-sensor combinations investigated were the normalized difference vegetation index (NDVI), the normalized difference red edge index (NDRE), and the reflectance ratio of near infrared minus red edge over near …


Narrow Grass Hedge Effects On Microbial Transport Following Variable Applications Of Beef Cattle Manure, Lisa M. Durso, John E. Gilley, Dave B. Marx, Brian L. Woodbury 2019 USDA-ARS, Meat Animal Research Center

Narrow Grass Hedge Effects On Microbial Transport Following Variable Applications Of Beef Cattle Manure, Lisa M. Durso, John E. Gilley, Dave B. Marx, Brian L. Woodbury

Department of Biological Systems Engineering: Papers and Publications

The effectiveness of a 1.4 m wide grass hedge in reducing microbial transport following manure application was examined in this study. Beef cattle manure was applied to 0.75 m wide by 4.0 m long plots established on an Aksarben silty clay loam located in southeast Nebraska. Manure was added at rates required to meet none or the 1-, 2-, or 4-year nitrogen requirements for corn. The transport of phages, total coliforms, E. coli, and enterococci was measured for three 30 min simulated rainfall events, which were separated by approximately 24 h intervals. The narrow grass hedge reduced total counts of …


Identifying Advantages And Disadvantages Of Variable Rate Irrigation – An Updated Review, S. A. O’Shaughnessy, Steve R. Evett, Paul D. Colaizzi, Manuel A. Andrade, Thomas H. Marek, Derek M. Heeren, Freddie R. Lamm, Jacob L. LaRue 2019 USDA-ARS, Soil and Water Management Research Unit,

Identifying Advantages And Disadvantages Of Variable Rate Irrigation – An Updated Review, S. A. O’Shaughnessy, Steve R. Evett, Paul D. Colaizzi, Manuel A. Andrade, Thomas H. Marek, Derek M. Heeren, Freddie R. Lamm, Jacob L. Larue

Department of Biological Systems Engineering: Papers and Publications

Variable rate irrigation (VRI) sprinklers on mechanical move irrigation systems (center pivot or lateral move) have been commercially available since 2004. Although the number of VRI, zone or individual sprinkler, systems adopted to date is lower than expected there is a continued interest to harness this technology, especially when climate variability, regulatory nutrient management, water conservation policies, and declining water for agriculture compound the challenges involved for irrigated crop production. This article reviews the potential advantages and potential disadvantages of VRI technology for moving sprinklers, provides updated examples on such aspects, suggests a protocol for designing and implementing VRI technology …


Minimal Interspecies Interaction Adjustment (Miia): Inference Of Neighbor-Dependent Interactions In Microbial Communities, Hyun-Seob Song, Joon-Yong Lee, Shin Haruta, William C. Nelson, Dong-Yup Lee, Stephen R. Lindemann, Jim K. Fredrickson, Hans C. Bernstein 2019 Pacific Northwest National Laboratory

Minimal Interspecies Interaction Adjustment (Miia): Inference Of Neighbor-Dependent Interactions In Microbial Communities, Hyun-Seob Song, Joon-Yong Lee, Shin Haruta, William C. Nelson, Dong-Yup Lee, Stephen R. Lindemann, Jim K. Fredrickson, Hans C. Bernstein

Department of Biological Systems Engineering: Papers and Publications

An intriguing aspect in microbial communities is that pairwise interactions can be influenced by neighboring species. This creates context dependencies for microbial interactions that are based on the functional composition of the community. Context dependent interactions are ecologically important and clearly present in nature, yet firmly established theoretical methods are lacking from many modern computational investigations. Here, we propose a novel network inference method that enables predictions for interspecies interactions affected by shifts in community composition and species populations. Our approach first identifies interspecies interactions in binary communities, which is subsequently used as a basis to infer modulation in more …


Principal Variable Selection To Explain Grain Yield Variation In Winter Wheat From Features Extracted From Uav Imagery, Jiating Li, Arun-Narenthiran Veeranampalayam-Sivakumar, Madhav Bhatta, Nicholas D. Garst, Hannah Stoll, P. Stephen Baenziger, Vikas Belamkar, Reka Howard, Yufeng Ge, Jiating Li 2019 University of Nebraska - Lincoln

Principal Variable Selection To Explain Grain Yield Variation In Winter Wheat From Features Extracted From Uav Imagery, Jiating Li, Arun-Narenthiran Veeranampalayam-Sivakumar, Madhav Bhatta, Nicholas D. Garst, Hannah Stoll, P. Stephen Baenziger, Vikas Belamkar, Reka Howard, Yufeng Ge, Jiating Li

Department of Biological Systems Engineering: Papers and Publications

Background: Automated phenotyping technologies are continually advancing the breeding process. However, collecting various secondary traits throughout the growing season and processing massive amounts of data still take great efforts and time. Selecting a minimum number of secondary traits that have the maximum predictive power has the potential to reduce phenotyping efforts. The objective of this study was to select principal features extracted from UAV imagery and critical growth stages that contributed the most in explaining winter wheat grain yield. Five dates of multispectral images and seven dates of RGB images were collected by a UAV system during the spring growing …


High-Speed, High-Frequency Ultrasound, In Utero Vector-Flow Imaging Of Mouse Embryos, Jeffrey A. Ketterling, Orlando Aristizabal, Billy Y. S. Yiu, Daniel H. Turnbull, Colin K. L. Phoon, Alfred C. H. Yu, Ronald H. Silverman 2019 Frederic Lizzi Center for Biomedical Engineering

High-Speed, High-Frequency Ultrasound, In Utero Vector-Flow Imaging Of Mouse Embryos, Jeffrey A. Ketterling, Orlando Aristizabal, Billy Y. S. Yiu, Daniel H. Turnbull, Colin K. L. Phoon, Alfred C. H. Yu, Ronald H. Silverman

Department of Biological Systems Engineering: Papers and Publications

Real-time imaging of the embryonic murine cardiovascular system is challenging due to the small size of the mouse embryo and rapid heart rate. High-frequency, linear-array ultrasound systems designed for small-animal imaging provide high-frame-rate and Doppler modes but are limited in regards to the field of view that can be imaged at fine-temporal and -spatial resolution. Here, a plane-wave imaging method was used to obtain high-speed image data from in utero mouse embryos and multi-angle, vector-flow algorithms were applied to the data to provide information on blood flow patterns in major organs. An 18-MHz linear array was used to acquire plane-wave …


Agenator: An Open Source Computer-Controlled Dry Aging System For Beef, Soon Kiat Lau, Felipe Azevedo Ribeiro, Jeyamkondan Subbiah, Chris R. Calkins 2019 University of Nebraska-Lincoln

Agenator: An Open Source Computer-Controlled Dry Aging System For Beef, Soon Kiat Lau, Felipe Azevedo Ribeiro, Jeyamkondan Subbiah, Chris R. Calkins

Department of Biological Systems Engineering: Papers and Publications

Dry aging of beef is a process where beef is exposed to a controlled environment with the ultimate goal of drying the beef to improve its quality and value. Comprehensive investigations into the effects of various environmental conditions on dry aging are crucial for understanding and optimizing the process, but the lack of affordable equipment focused on data collection makes it difficult to do so. The Agenator was thus developed as an open source system with a suite of features for investigating dry aging such as: measuring and recording relative humidity, temperature, mass, air velocity, and fan rotational speed; precise …


Factors Related To Intra-Tendinous Morphology Of Achilles Tendon In Runners, Kai-Yu Ho, Ari Baquet, Yu-Jen Chang, Lung-Chang Chien, Michelle Harty, Gregory Bashford, Kornelia Kulig 2019 University of Nevada, Las Vegas

Factors Related To Intra-Tendinous Morphology Of Achilles Tendon In Runners, Kai-Yu Ho, Ari Baquet, Yu-Jen Chang, Lung-Chang Chien, Michelle Harty, Gregory Bashford, Kornelia Kulig

Department of Biological Systems Engineering: Papers and Publications

The purpose of this study was to determine and explore factors (age, sex, anthropometry, running and injury/pain history, tendon gross morphology, neovascularization, ankle range of motion, and ankle plantarflexor muscle endurance) related to intra-tendinous morphological alterations of the Achilles tendon in runners. An intra-tendinous morphological change was defined as collagen fiber disorganization detected by a low peak spatial frequency radius (PSFR) obtained from spatial frequency analysis (SFA) techniques in sonography. Ninety-one runners (53 males and 38 females; 37.9 ± 11.6 years) with 8.8 ± 7.3 years of running experience participated. Height, weight, and waist and hip circumferences were recorded. Participants …


A Machine Learning Approach For Improving Near-Real-Time Satellite-Based Rainfall Estimates By Integrating Soil Moisture, Ashish Kumar, RAAJ Ramsankaran, Luca Brocca, Francisco Munoz-Arriola 2019 Indian Institute of Technology Bombay

A Machine Learning Approach For Improving Near-Real-Time Satellite-Based Rainfall Estimates By Integrating Soil Moisture, Ashish Kumar, Raaj Ramsankaran, Luca Brocca, Francisco Munoz-Arriola

Department of Biological Systems Engineering: Papers and Publications

Near-real-time (NRT) satellite-based rainfall estimates (SREs) are a viable option for flood/drought monitoring. However, SREs have often been associated with complex and nonlinear errors. One way to enhance the quality of SREs is to use soil moisture information. Few studies have indicated that soil moisture information can be used to improve the quality of SREs. Nowadays, satellite-based soil moisture products are becoming available at desired spatial and temporal resolutions on an NRT basis. Hence, this study proposes an integrated approach to improve NRT SRE accuracy by combining it with NRT soil moisture through a nonlinear support vector machine-based regression (SVR) …


Patellar Tendon Morphology In Trans-Tibial Amputees Utilizing A Prosthesis With A Patellar-Tendonbearing Feature, Kai-Yu Ho, Michelle Harty, Jessica Kellogg, Kelly Teter, Szu-Ping Lee, Yu-Jen Chang, Gregory Bashford 2019 University of Nevada, Las Vegas

Patellar Tendon Morphology In Trans-Tibial Amputees Utilizing A Prosthesis With A Patellar-Tendonbearing Feature, Kai-Yu Ho, Michelle Harty, Jessica Kellogg, Kelly Teter, Szu-Ping Lee, Yu-Jen Chang, Gregory Bashford

Department of Biological Systems Engineering: Papers and Publications

A patellar-tendon-bearing (PTB) bar is a common design feature used in the socket of trans-tibial prostheses to place load on the pressure-tolerant tissue. As the patellar tendon in the residual limb is subjected to the perpendicular compressive force not commonly experienced in normal tendons, it is possible for tendon degeneration to occur over time. The purpose of this study was to compare patellar tendon morphology and neovascularity between the residual and intact limbs in trans-tibial amputees and healthy controls. Fifteen unilateral trans-tibial amputees who utilized a prosthesis with a PTB feature and 15 age- and sex- matched controls participated. Sonography …


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