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Full-Text Articles in Engineering

Setback Distance Requirements For Removal Of Swine Slurry Constituents In Runoff, John E. Gilley, Shannon L. Bartelt-Hunt, Kent M. Eskridge, Xu Li, Amy M. Schmidt, Daniel D. Snow Dec 2017

Setback Distance Requirements For Removal Of Swine Slurry Constituents In Runoff, John E. Gilley, Shannon L. Bartelt-Hunt, Kent M. Eskridge, Xu Li, Amy M. Schmidt, Daniel D. Snow

Biological Systems Engineering: Papers and Publications

The use of setback distances for manure application on cropland areas adjacent to surface water bodies could serve a function similar to vegetative filter strips. However, little information currently exists to identify the setback distances necessary to effectively reduce the transport of contaminants in runoff. The objective of this study was to determine the effects of setback distance and runoff rate on concentrations of selected constituents in runoff following land application of swine slurry to a no-till cropland area in southeast Nebraska. The study site had a residue cover of 7.73 Mg ha-1 and a slope gradient of 4.9%. The …


Quantifying Effectiveness Of Streambank Stabilization Practices On Cedar River, Nebraska, Naisargi Dave, Aaron R. Mittelstet Nov 2017

Quantifying Effectiveness Of Streambank Stabilization Practices On Cedar River, Nebraska, Naisargi Dave, Aaron R. Mittelstet

Biological Systems Engineering: Papers and Publications

Excessive sediment is a major pollutant to surface waters worldwide. In some watersheds, streambanks are a significant source of this sediment, leading to the expenditure of billions of dollars in stabilization projects. Although costly streambank stabilization projects have been implemented worldwide, long-term monitoring to quantify their success is lacking. There is a critical need to document the long-term success of streambank restoration projects. The objectives of this research were to (1) quantify streambank retreat before and after the stabilization of 18 streambanks on the Cedar River in North Central Nebraska, USA; (2) assess the impact of a large flood event; …


Spatial And Temporal Variation In Precipitation In Togo, Koffi Djaman, Vivek Sharma, Daran Rudnick, Komlan Koudahe, Suat Irkmak, Kokou Adambounou Amouzou, Jean Mianikpo Sogbedji Oct 2017

Spatial And Temporal Variation In Precipitation In Togo, Koffi Djaman, Vivek Sharma, Daran Rudnick, Komlan Koudahe, Suat Irkmak, Kokou Adambounou Amouzou, Jean Mianikpo Sogbedji

Biological Systems Engineering: Papers and Publications

Precipitation is one of the important variables in hydrological cycle and has important application in both irrigated and rainfed agricultural crop production. Better understanding of spatio-temporal variability of precipitation across Togo is important and useful for water users and most agricultural activities. Thus, the objective this study was to analyze the spatial and temporal variation in monthly and annual precipitation across Togo for the period of 1961-2001. Monthly precipitation data was provided by the national direction of meteorology. The performed analysis revealed a decline in annual total precipitation across almost all agro-ecological zones in Togo with the Maritime Region revealed …


Geometry-Based Mass Grading Of Mango Fruits Using Image Processing, M. A. Momin, Md Towfiqur Rahman, M. S. Sultana, C. Igathinathane, A. T. M. Ziauddin, T. E. Grift Jun 2017

Geometry-Based Mass Grading Of Mango Fruits Using Image Processing, M. A. Momin, Md Towfiqur Rahman, M. S. Sultana, C. Igathinathane, A. T. M. Ziauddin, T. E. Grift

Biological Systems Engineering: Papers and Publications

Mango (Mangifera indica) is an important, and popular fruit in Bangladesh. However, the post-harvest processing of it is still mostly performed manually, a situation far from satisfactory, in terms of accuracy and throughput. To automate the grading of mangos (geometry and shape), we developed an image acquisition and processing system to extract projected area, perimeter, and roundness features. In this system, images were acquired using a XGA format color camera of 8-bit gray levels using fluorescent lighting. An image processing algorithm based on region based global thresholding color binarization, combined with median filter and morphological analysis was developed …


Sensor System, Implantable Sensor And Method For Remote Sensing Of A Stimulus In Vivo, Eric H. Ledet, Rebecca A. Wachs, Keegan Paul Cole, David Fiorella May 2017

Sensor System, Implantable Sensor And Method For Remote Sensing Of A Stimulus In Vivo, Eric H. Ledet, Rebecca A. Wachs, Keegan Paul Cole, David Fiorella

Biological Systems Engineering: Papers and Publications

A sensor system for sensing a stimulus in vivo includes an implantable sensor. The sensor comprises a passive resonator circuit having a resonant frequency and including at least a pair of generally parallel spirally wound unconnected conductive coils sandwiching a layer of solid dielectric material that manifest a change in property affecting the resonant frequency in response to application of the stimulus to the layer. A resonant frequency of the sensor is modulated by altering the spacing or gap between the coils or altering the overlapping area of the coils. The sensor is energized through application of radio frequency energy …


Supraspinatus Tendon Micromorphology In Individuals With Subacromial Pain Syndrome, Federico Pozzi, Amee L. Seitz, Hillary A. Plummer, Kira Chow, Gregory R. Bashford, Lori A. Michener May 2017

Supraspinatus Tendon Micromorphology In Individuals With Subacromial Pain Syndrome, Federico Pozzi, Amee L. Seitz, Hillary A. Plummer, Kira Chow, Gregory R. Bashford, Lori A. Michener

Biological Systems Engineering: Papers and Publications

Study Design: Cross-sectional cohort. Introduction: Tendon collagen organization can be estimated by peak spatial frequency radius (PSFR) on ultrasound images. Characterizing PSFR can define the contribution of collagen disruption to shoulder symptoms.

Purpose of the Study: The purpose of this was to characterize the (1) supraspinatus tendon PSFR in participants with sub acromial pain syndrome (SPS) and healthy controls; (2) PSFR between participants grouped on a tendon visual quality score; and (3) relationship between PSFR with patient-reported pain, function, and shoulder strength.

Methods: Participants with SPS (n ¼ 20) and age, sex, and arm-dominance matched healthy controls (n ¼ 20) …


Method For The Production Of Substituted Polysaccharides Via Reactive Extrusion, Milford Hanna, Pratik Bhandari May 2017

Method For The Production Of Substituted Polysaccharides Via Reactive Extrusion, Milford Hanna, Pratik Bhandari

Biological Systems Engineering: Papers and Publications

A reactive extrusion process for the production of substituted polysaccharides, in particular, cellulose acetate, starch acetate, carboxymethyl cellulose, and carboxymethyl starch.

The present application claims the benefit of PCT/ US20111059785 filed on Nov. 8, 2011, which claimed the benefit of U.S. provisional application 611411,521, filed on Nov. 9, 2010, U.S. provisional application 611411,992, filed on Nov. 10, 2010, and U.S. provisional application 611472, 748, filed on Apr. 7, 2011, each of which is which is incorporated herein by reference in its entirety.

The production of substituted polysaccharides such as starch and cellulose acetates and carboxymethylated starches and celluloses have typically …


Center Pivot Irrigation Handbook (Ec3017), Derrel Martin, William Kranz, Tyler Smith, Suat Irmak, Charles Burr, Ron Yoder Feb 2017

Center Pivot Irrigation Handbook (Ec3017), Derrel Martin, William Kranz, Tyler Smith, Suat Irmak, Charles Burr, Ron Yoder

Biological Systems Engineering: Papers and Publications

Center pivot irrigation has been the most rapidly expanding form of irrigation in the Central Great Plains and across the United States. The amount of land irrigated with sprinkler, gravity and drip or trickle systems was determined for all states in the USA in the Farm and Ranch Irrigation Survey1 by the USDA in 2012. Results of the survey for the Great Plains States shows that approximately 85% of the land in Nebraska is irrigated with center pivots and that very little land was irrigated with drip systems in 2012 (Figure 1). The percentage of land irrigated with sprinklers in …


Tissue Decellularization Methods, Christine E. Schmidt, Rebecca A. Wachs, Robert Chase Cornelison Jan 2017

Tissue Decellularization Methods, Christine E. Schmidt, Rebecca A. Wachs, Robert Chase Cornelison

Biological Systems Engineering: Papers and Publications

Provided herein are methods of producing an acellular tissue product wherein the method can include the step of inducing apoptosis and washing the tissue after induction of apoptosis with a tonic solution. Also provided herein are acellular tissue products produced by the methods provided herein and methods of administering the acellular tissue products to a subject in need thereof.


Multiple Drivers Of Seasonal Change In Pri: Implications For Photosynthesis 1. Leaf Level, Anatoly A. Gitelson, John A. Gamon, Alexei E. Solovchenko Jan 2017

Multiple Drivers Of Seasonal Change In Pri: Implications For Photosynthesis 1. Leaf Level, Anatoly A. Gitelson, John A. Gamon, Alexei E. Solovchenko

Biological Systems Engineering: Papers and Publications

The goal of this study was to explore the relationships between the photochemical reflectance index (PRI) at the leaf level and pigment pools, focusing on the constitutive role of pigments in influencing PRI over seasonal or ontogenetic time frames. The purpose was to re-evaluate the role of PRI as an indicator of seasonally shifting pigment (chlorophyll, carotenoid and anthocyanin) contents, and hence photosynthetic activity, across a range of tree and crop species. We studied natural vegetation — three tree species (maple, chestnut and beech) and two managed irrigated and rain-fed crop species (maize and soybean), contrasting in photosynthetic pathway and …


Correction: Messer, T.L.; Burchell, M.R.; Birgand, F. Comparison Of Four Nitrate Removal Kinetic Models In Two Distinct Wetland Restoration Mesocosm Systems. Water 2017, 9, 517, Tiffany L. Messer, Michael R. Burchell, François Birgand Jan 2017

Correction: Messer, T.L.; Burchell, M.R.; Birgand, F. Comparison Of Four Nitrate Removal Kinetic Models In Two Distinct Wetland Restoration Mesocosm Systems. Water 2017, 9, 517, Tiffany L. Messer, Michael R. Burchell, François Birgand

Biological Systems Engineering: Papers and Publications

The authors wish to make the following corrections to this paper [1]:

(1): The author name “François Bírgand” should be François Birgand.

(2): Reference 38 should be the following:

Birgand, F.; Aveni-Deforge, K.; Smith, B.; Maxwell, B.M.; Horstman, M.; Gerling, A.B.; Carey, C.C. First report of a novel multiplexer pumping system coupled to a water quality probe to collect high temporal frequency in situ water chemistry measurements at multiple sites. Limnol. Oceanogr. Methods 2016, 14, 767–783, doi:10.1002/lom3.10122.

(3): Reference 49 should be the following:

Christensen, P.B.; Nielsen, L.P.; Sørensen, J.; Revsbech, N.P. Denitrification in Nitrate-Rich Streams: Diurnal and Seasonal Variation …


Fuel Consumption Models For Tractor Test Reports, Michael F. Kocher, Bryan J. Smith, Roger M. Hoy, Jeffrey C. Woldstad, Santosh Pitla Jan 2017

Fuel Consumption Models For Tractor Test Reports, Michael F. Kocher, Bryan J. Smith, Roger M. Hoy, Jeffrey C. Woldstad, Santosh Pitla

Biological Systems Engineering: Papers and Publications

Five models for estimating fuel consumption for agricultural tractors with partial drawbar loads were compared. Data were collected from eight John Deere tractors, JD 7230R (e23), 7250R (e23), 7270R (e23), 7290R (e23), 8320R (16 speed), 7290R (IVT), 8345RT (IVT), 8370R (IVT), on the drawbar test track at the Nebraska Tractor Test Lab. The tractors were tested with seven load levels per speed at three different travel speeds as close as possible to 7.5, 10, and 13 km h-1. The IVT tractors were operated in auto mode, and the geared tractors were shifted up three gears and throttled back to the …


Spatial And Temporal Changes In Maize And Soybean Grain Yield, Precipitation Use Efficiency, And Crop Water Productivity In The U.S. Great Plains, Meetpal S. Kukal, S. Irmak Jan 2017

Spatial And Temporal Changes In Maize And Soybean Grain Yield, Precipitation Use Efficiency, And Crop Water Productivity In The U.S. Great Plains, Meetpal S. Kukal, S. Irmak

Biological Systems Engineering: Papers and Publications

Sustainable agricultural utilization of the limited water resources demands improvements in understanding the changes in crop water productivity (CWP) in space and time, which is often presented as a potential solution to relieve the growing pressure on fresh water resources. In addition, crop yield needs to be studied in relation to precipitation received annually and during the growing season for its contribution to reduce irrigation water requirements, which is quantified through precipitation use efficiency (PUE). Hence, systematic quantifications, mapping, and analyses of large-scale CWP and PUE levels are needed. This study aims to quantify long-term (1982-2013) information on grain yield, …


Large Co2 And Ch4 Emissions From Polygonal Tundra During Spring Thaw In Northern Alaska, Naama Raz-Yaseef, Margaret S. Torn, Yuxin Wu, David P. Billesbach, Anna K. Liljedahl, Timothy J. Kneafsey, Vladimir E. Romanovsky, David R. Cook, Stan D. Wullschleger Jan 2017

Large Co2 And Ch4 Emissions From Polygonal Tundra During Spring Thaw In Northern Alaska, Naama Raz-Yaseef, Margaret S. Torn, Yuxin Wu, David P. Billesbach, Anna K. Liljedahl, Timothy J. Kneafsey, Vladimir E. Romanovsky, David R. Cook, Stan D. Wullschleger

Biological Systems Engineering: Papers and Publications

The few prethaw observations of tundra carbon fluxes suggest that there may be large spring releases, but little is known about the scale and underlying mechanisms of this phenomenon. To address these questions, we combined ecosystem eddy flux measurements from two towers near Barrow, Alaska, with mechanistic soil-core thawing experiment. During a 2 week period prior to snowmelt in 2014, large fluxes were measured, reducing net summer uptake of CO2 by 46% and adding 6% to cumulative CH4 emissions. Emission pulses were linked to unique rain-on-snow events enhancing soil cracking. Controlled laboratory experiment revealed that as surface ice …


Laboratory And Full Boom-Based Investigation Of Nozzle Setup Error Effects On Flow, Pressure, And Spray Pattern Distribution, S. H. Forney, J. D. Luck, Michael F. Kocher, Santosh K. Pitla Jan 2017

Laboratory And Full Boom-Based Investigation Of Nozzle Setup Error Effects On Flow, Pressure, And Spray Pattern Distribution, S. H. Forney, J. D. Luck, Michael F. Kocher, Santosh K. Pitla

Biological Systems Engineering: Papers and Publications

Pesticide application is an integral part of crop production, and ground-based agricultural boom sprayers are used extensively to apply pesticides to the crop canopy or soil surface across millions of acres in the United States. Efficient application is necessary to minimize costs and limit adverse environmental impacts. The goals of this study were to provide quantified measurements on the effects of nozzle setup errors on spray pattern uniformity and evaluate how laboratory patternator-based simulations would compare to measurements on a full spray boom. More specific objectives were to determine the effects of factors such as nozzle lateral angle, nozzle spacing, …


Development And Validation Of A Tractor Drawbar Force Measurement And Data Acquisition System (Daq), James Roeber, Santosh Pitla, Roger M. Hoy, Joe D. Luck, Michael F. Kocher Jan 2017

Development And Validation Of A Tractor Drawbar Force Measurement And Data Acquisition System (Daq), James Roeber, Santosh Pitla, Roger M. Hoy, Joe D. Luck, Michael F. Kocher

Biological Systems Engineering: Papers and Publications

Matching agricultural tractors to implements towed by the drawbar is one of the important aspects of machinery management for ensuring optimum performance and fuel cost savings. A field deployable tractor draft force measurement and data acquisition system was developed and evaluated as part of this research project. A drawbar instrumented to measure draft force in field operating conditions was developed and statically calibrated. The drawbar was calibrated by applying loads from 4.45 to 134 kN using a hydraulic cylinder connected to a 444.8 kN load cell. Testing was conducted with the drawbar installed on a tractor on a concrete track. …


Trend Analysis In Rainfall, Reference Evapotranspiration And Aridity Index In Southern Senegal: Adaptation To The Vulnerability Of Rainfed Rice Cultivation To Climate Change, Komlan Koudahe, Koffi Djaman, Ansoumana Bodian, Suat Irkmak, Mamadou Sall, Lamine Diop, Alpha B. Balde, Daran Rudnick Jan 2017

Trend Analysis In Rainfall, Reference Evapotranspiration And Aridity Index In Southern Senegal: Adaptation To The Vulnerability Of Rainfed Rice Cultivation To Climate Change, Komlan Koudahe, Koffi Djaman, Ansoumana Bodian, Suat Irkmak, Mamadou Sall, Lamine Diop, Alpha B. Balde, Daran Rudnick

Biological Systems Engineering: Papers and Publications

Rainfall and evapotranspiration are two vital elements for food production under rainfed agriculture. This study aims at investigating the combined changes in these variables in the form of aridly index in the southern Senegal. The temporal trends in annual and monthly (from May to October) aridity index, rainfall and evapotranspiration are examined and adaptation strategies to the vulnerability of rainfed rice cultivation to the changes are developed. The results show a significant decreasing trend in annual rainfall at all study locations for the period 1922-2015. When analyzing the trends in sub-periods, there are two clear patterns in the annual rainfall …


Runoff Water Quality Characteristics Following Swine Slurry Application Under Broadcast And Injected Conditions, Nicole R. Schuster, Shannon L. Bartelt-Hunt, Lisa M. Durso, John E. Gilley, Xu Li, David B. Marx, Amy M. Schmidt, Daniel D. Snow Jan 2017

Runoff Water Quality Characteristics Following Swine Slurry Application Under Broadcast And Injected Conditions, Nicole R. Schuster, Shannon L. Bartelt-Hunt, Lisa M. Durso, John E. Gilley, Xu Li, David B. Marx, Amy M. Schmidt, Daniel D. Snow

Biological Systems Engineering: Papers and Publications

This study was conducted to measure the effects of swine slurry application method, time following slurry application, and runoff rate on selected water quality characteristics. Slurry from a commercial swine operation was broadcast or injected on field plots at a rate required to meet annual nitrogen requirements for corn. Rainfall simulation tests were conducted at five varying periods following slurry application. During each study period, three simulated rainfall events, separated by 24 h intervals, were applied for 30 min duration at an intensity of approximately 70 mm h-1. Following the third rainfall simulation event, inflow was applied at …


Soil Water Content Monitoring For Irrigation Management: A Geostatistical Analysis, J. Burdette Barker, Trenton E. Franz, Derek M. Heeren, Christopher M.U. Neale, Joe D. Luck Jan 2017

Soil Water Content Monitoring For Irrigation Management: A Geostatistical Analysis, J. Burdette Barker, Trenton E. Franz, Derek M. Heeren, Christopher M.U. Neale, Joe D. Luck

Biological Systems Engineering: Papers and Publications

With the increasing attention to site-specific or variable rate irrigation management, it is helpful to reconsider the quantity and placement of soil water monitoring locations in this context. Volumetric soil water content (θv) was monitored using a neutron probe (NP) at 72 locations in a center pivot irrigated field in eastern Nebraska. Variance reduction and temporal stability analyses were performed on θv from shallow (∼top 46 cm) and full profile (∼122 cm) readings for four monitoring cycles in the 2015 growing season and 2016 preseason. Eleven additional cycles were included for a subset of the data for …


Evaluation Of Valiantzas’ Simplified Forms Of The Fao-56 Penman-Monteith Reference Evapotranspiration Model In A Humid Climate, Koffi Djaman, Daran Rudnick, Valere C. Mel, Denis Mutiibwa, Lamine Diop, Mamadou Sall, Isa Kabenge, Ansoumana Bodian, Hossein Tabari, Suat Irmak Jan 2017

Evaluation Of Valiantzas’ Simplified Forms Of The Fao-56 Penman-Monteith Reference Evapotranspiration Model In A Humid Climate, Koffi Djaman, Daran Rudnick, Valere C. Mel, Denis Mutiibwa, Lamine Diop, Mamadou Sall, Isa Kabenge, Ansoumana Bodian, Hossein Tabari, Suat Irmak

Biological Systems Engineering: Papers and Publications

The unavailability of some meteorological variables, especially solar radiation and wind speed, is the main constraint for reference evapotranspiration (ETo) estimation using the standard United Nations Food and Agriculture Organization (FAO) Penman–Monteith (FAO-PM) equation in most developing countries. The application of ETo methods with fewer input requirements is necessary under limited climatic data conditions. The FAO-PM method under limited data conditions and nine of Valiantzas’ equations were evaluated for daily ETo estimation in a humid climate in Uganda. The FAO-PM method with missing relative humidity data performed very well across Uganda, whereas using the long-term local wind speed average values …


Crop Canopy Sensor Orientation For Late Season Nitrogen Determination In Corn, T. M. Shaver, Greg Kruger, Daran Rudnick Jan 2017

Crop Canopy Sensor Orientation For Late Season Nitrogen Determination In Corn, T. M. Shaver, Greg Kruger, Daran Rudnick

Biological Systems Engineering: Papers and Publications

Increasing nitrogen use efficiency (NUE) in irrigated corn production is of great importance to overall agricultural sustainability. Studies have shown that crop canopy sensors can aid in this pursuit as they allow for the determination of nitrogen (N) requirements in split applications later in the growing season. Fertigation can also increase NUE as many split applications can be conducted. If crop canopy sensors could be used to direct N fertigation rates, overall NUE may be increased even further. However, in some cases, N differences may need to be determined later in the growing season after corn has tasseled, which can …


Nanoparticle For Targeting Brain Tumors And Delivery Of O6 - Benzylguanine, University Of Washington, Seattle Jan 2017

Nanoparticle For Targeting Brain Tumors And Delivery Of O6 - Benzylguanine, University Of Washington, Seattle

Biological Systems Engineering: Papers and Publications

Nanoparticle having a crosslinked chitosan - polyethylene oxide oligomer copolymer coating to which O6 - benzylgua nine is covalently coupled , compositions that include the nanoparticle , and methods for using the nanoparticle to treat brain cancers .


Crop Classification And Lai Estimation Using Original And Resolution-Reduced Images From Two Consumer-Grade Cameras, Jian Zhang, Chenghai Yang, Biquan Zhao, Huaibo Song, Wesley Clint Hoffmann, Yeyin Shi, Dongyan Zhang, Guozhong Zhang Jan 2017

Crop Classification And Lai Estimation Using Original And Resolution-Reduced Images From Two Consumer-Grade Cameras, Jian Zhang, Chenghai Yang, Biquan Zhao, Huaibo Song, Wesley Clint Hoffmann, Yeyin Shi, Dongyan Zhang, Guozhong Zhang

Biological Systems Engineering: Papers and Publications

Consumer-grade cameras are being increasingly used for remote sensing applications in recent years. However, the performance of this type of cameras has not been systematically tested and well documented in the literature. The objective of this research was to evaluate the performance of original and resolution-reduced images taken from two consumer-grade cameras, a RGB camera and a modified near-infrared (NIR) camera, for crop identification and leaf area index (LAI) estimation. Airborne RGB and NIR images taken over a 6.5-square-km cropping area were mosaicked and aligned to create a four-band mosaic with a spatial resolution of 0.4 m. The spatial resolution …


The Effect Of Single-Handed Lifting Tasks On The Activation Of The Neck-Shoulder Shared Musculature, Mohamed R. Amar, David Cochran, Jeffrey Woldstad Jan 2017

The Effect Of Single-Handed Lifting Tasks On The Activation Of The Neck-Shoulder Shared Musculature, Mohamed R. Amar, David Cochran, Jeffrey Woldstad

Biological Systems Engineering: Papers and Publications

The use of the hand in lifting has been linked to occupational injuries of the neck and shoulder. This research is aimed at examining the effect of work-related factors on the major neck-shoulder shared musculature activity on both sides of the cervical spine for a right-handed lifting task. Subjects lifted different weights from 20 different locations produced by the interaction of varying heights, reach distance, and angles simulating the work done by assembly line workers. All lifting tasks were done by the right hand. Bilateral electromyography data of major shared musculature (upper trapezius, sternocleidomastoid, and levator scapula) were collected using …


Regulation-Structured Dynamic Metabolic Model Provides A Potential Mechanism For Delayed Enzyme Response In Denitrification Process, Hyun-Seob Song, Dennis G. Thomas, James C. Stegen, Minjing Li, Chongxuan Liu, Xuehang Song, Xingyuan Chen, Jim K. Fredrickson, John M. Zachara, Timothy D. Scheibe Jan 2017

Regulation-Structured Dynamic Metabolic Model Provides A Potential Mechanism For Delayed Enzyme Response In Denitrification Process, Hyun-Seob Song, Dennis G. Thomas, James C. Stegen, Minjing Li, Chongxuan Liu, Xuehang Song, Xingyuan Chen, Jim K. Fredrickson, John M. Zachara, Timothy D. Scheibe

Biological Systems Engineering: Papers and Publications

In a recent study of denitrification dynamics in hyporheic zone sediments, we observed a significant time lag (up to several days) in enzymatic response to the changes in substrate concentration. To explore an underlying mechanism and understand the interactive dynamics between enzymes and nutrients, we developed a trait-based model that associates a community’s traits with functional enzymes, instead of typically used species guilds (or functional guilds). This enzyme-based formulation allows to collectively describe biogeochemical functions of microbial communities without directly parameterizing the dynamics of species guilds, therefore being scalable to complex communities. As a key component of modeling, we accounted …


Moving Integrated Weed Management From Low Level To A Truly Integrated And Highly Specific Weed Management System Using Advanced Technologies, S. L. Young, S. K. Pitla, F. K. Van Evert, J. K. Schueller, F. J. Pierce Jan 2017

Moving Integrated Weed Management From Low Level To A Truly Integrated And Highly Specific Weed Management System Using Advanced Technologies, S. L. Young, S. K. Pitla, F. K. Van Evert, J. K. Schueller, F. J. Pierce

Biological Systems Engineering: Papers and Publications

Integrated weed management (IWM) is one of the most commonly referred to approaches for sustainable and effective weed control in agriculture, yet it is not widely practiced, likely because current IWM systems fail to meet performance expectations of growers. The effectiveness and value of IWM systems should increase with increasing application specificity and true integration made possible with contemporary advances in technology, information systems and decision support. IWM systems can be classified based on their degree of application specificity and level of integration of tactics. In the application specificity pathway, a tactic is applied at a range of scales, from …


Optical Probing Of Gastrocnemius In Patients With Peripheral Artery Disease Characterizes Myopathic Biochemical Alterations And Correlates With Stage Of Disease, Ryan A. Becker, Kim Cluff, Nithyanandhi Duraisamy, Hootan Mehraein, Hussam Farhoud, Tracie Collins, George P. Casale, Iraklis I. Pipinos, Jeyamkondan Subbiah Jan 2017

Optical Probing Of Gastrocnemius In Patients With Peripheral Artery Disease Characterizes Myopathic Biochemical Alterations And Correlates With Stage Of Disease, Ryan A. Becker, Kim Cluff, Nithyanandhi Duraisamy, Hootan Mehraein, Hussam Farhoud, Tracie Collins, George P. Casale, Iraklis I. Pipinos, Jeyamkondan Subbiah

Biological Systems Engineering: Papers and Publications

Peripheral artery disease (PAD) is a condition caused by atherosclerotic blockages in the arteries supplying the lower limbs and is characterized by ischemia of the leg, progressive myopathy, and increased risk of limb loss. The affected leg muscles undergo significant changes of their biochemistry and metabolism including variations in the levels of many key proteins, lipids, and nucleotides. The mechanisms behind these changes are poorly understood. The objective of this study was to correlate the severity of the PAD disease stage and associated hemodynamic limitation (determined by the ankle brachial index, ABI) in the legs of the patients with alterations …


Multiple Drivers Of Seasonal Change In Pri: Implications For Photosynthesis 2. Stand Level, Anatoly A. Gitelson, John A. Gamon, Alexei E. Solovchenko Jan 2017

Multiple Drivers Of Seasonal Change In Pri: Implications For Photosynthesis 2. Stand Level, Anatoly A. Gitelson, John A. Gamon, Alexei E. Solovchenko

Biological Systems Engineering: Papers and Publications

The goal of this study was to explore the relationships between stand-level photochemical reflectance index (PRI) and canopy structure/ pigment pools, as well as light use efficiency (LUE) of photosynthetically active vegetation focusing on seasonal or ontogenetic time frames. PRI was originally designed as a means of assessing the xanthophyll cycle and LUE over short (e.g. diurnal) time frames, and few studies have explored the drivers of PRI over longer, seasonal time frames, particularly in crops having different photosynthetic pathways or canopy structures. Consequently, our purpose was to understand and quantify the drivers of PRI responses over seasonal time scales …


Creation Of An Injectable In Situ Gelling Native Extracellular Matrix For Nucleus Pulposus Tissue Engineering, Rebecca A. Wachs, Ella N. Hoogenboezem, Hammad I. Huda, Shangjing Xin, Stacy L. Porvasnik, Christine E. Schmidt Jan 2017

Creation Of An Injectable In Situ Gelling Native Extracellular Matrix For Nucleus Pulposus Tissue Engineering, Rebecca A. Wachs, Ella N. Hoogenboezem, Hammad I. Huda, Shangjing Xin, Stacy L. Porvasnik, Christine E. Schmidt

Biological Systems Engineering: Papers and Publications

Background Context: Disc degeneration is the leading cause of low back pain and is often characterized by a loss of disc height, resulting from cleavage of chondroitin sulfate proteoglycans (CSPGs) present in the nucleus pulposus. Intact CSPGs are critical to water retention and maintenance of the nucleus osmotic pressure. Decellularization of healthy nucleus pulposus tissue has the potential to serve as an ideal matrix for tissue engineering of the disc because of the presence of native disc proteins and CSPGs. Injectable in situ gelling matrices are the most viable therapeutic option to prevent damage to the anulus fibrosus and future …


In Vitro Porcine Blastocyst Development In Three-Dimensional Alginate Hydrogels, Jeremy R. Miles, Taylor D. Laughlin, Catherine Sargus-Patino, Angela K. Pannier Jan 2017

In Vitro Porcine Blastocyst Development In Three-Dimensional Alginate Hydrogels, Jeremy R. Miles, Taylor D. Laughlin, Catherine Sargus-Patino, Angela K. Pannier

Biological Systems Engineering: Papers and Publications

Appropriate embryonic and fetal development significantly impact pregnancy success and, therefore, the efficiency of swine production. The pre-implantation period of porcine pregnancy is characterized by several developmental hallmarks, which are initiated by the dramatic morphological change that occurs as pig blastocysts elongate from spherical to filamentous blastocysts. Deficiencies in blastocyst elongation contribute to approximately 20% of embryonic loss, and have a direct influence on within-litter birth weight variation. Although factors identified within the uterine environment may play a role in blastocyst elongation, little is known about the exact mechanisms by which porcine (or other species’) blastocysts initiate and progress through …