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Articles 1 - 30 of 31561

Full-Text Articles in Life Sciences

Stability Analysis Of Kernel Quality Traits In Exotic-Derived Doubled Haploid Maize Lines, Adam Vanous, Candice Gardner, Michael Blanco, Adam Martin-Schwarze, Jinyu Wang, Xianran Li, Alexander E. Lipka, Sherry Flint-Garcia, Martin Bohn, Jode Edwards, Thomas Lubberstedt Mar 2019

Stability Analysis Of Kernel Quality Traits In Exotic-Derived Doubled Haploid Maize Lines, Adam Vanous, Candice Gardner, Michael Blanco, Adam Martin-Schwarze, Jinyu Wang, Xianran Li, Alexander E. Lipka, Sherry Flint-Garcia, Martin Bohn, Jode Edwards, Thomas Lubberstedt

Agronomy Publications

Variation in kernel composition across maize (Zea mays L.) germplasm is affected by a combination of the plant’s genotype, the environment in which it is grown, and the interaction between these two elements. Adapting exotic germplasm to the US Corn Belt is highly dependent on the plant’s genotype, the environment where it is grown, and the interaction between these components. Phenotypic plasticity is ill-defined when specific exotic germplasm is moved over large latitudinal distances and for the adapted variants being created. Reduced plasticity (or stability) is desired for the adapted variants, as it allows for a more rapid ...


Planting Date, Hybrid Maturity, And Weather Effects On Maize Yield And Crop Stage, M. E. Baum, S. V. Archontoulis, M. A. Licht Jan 2019

Planting Date, Hybrid Maturity, And Weather Effects On Maize Yield And Crop Stage, M. E. Baum, S. V. Archontoulis, M. A. Licht

Agronomy Publications

Unfavorable weather conditions frequently cause farmers to plant maize (Zea mays L.) outside the optimum planting timeframe. We analyzed maize yield and phenology from a multilocation, year, hybrid relative maturity, and planting date experiment performed in Iowa, USA. Our objectives were to determine the optimum combination of planting date and relative maturity to maximize maize grain yield per environment and to elucidate the risk associated with the use of “full-season hybrids” when planting occurs beyond the optimum planting date. Analysis of variance (ANOVA) attributed 70% of the variability in grain yield to planting date and only 10% to relative maturity ...


Quantification Of Voc Emissions From Carbonized Refuse-Derived Fuel Using Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry, Andrzej Białowiec, Monika Micuda, Antoni Szumny, Jacek Łyczko, Jacek A. Koziel Dec 2018

Quantification Of Voc Emissions From Carbonized Refuse-Derived Fuel Using Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry, Andrzej Białowiec, Monika Micuda, Antoni Szumny, Jacek Łyczko, Jacek A. Koziel

Agricultural and Biosystems Engineering Publications

In this work, for the first time, the volatile organic compound (VOC) emissions from carbonized refuse-derived fuel (CRDF) were quantified on a laboratory scale. The analyzed CRDF was generated from the torrefaction of municipal waste. Headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) was used to identify 84 VOCs, including many that are toxic, e.g., derivatives of benzene or toluene. The highest emissions were measured for nonanal, octanal, and heptanal. The top 10 most emitted VOCs contributed to almost 65% of the total emissions. The VOC mixture emitted from torrefied CRDF differed from that emitted by other types ...


Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza Dec 2018

Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza

Agronomy Publications

The anticipated world population growth emphasizes a need to produce more food on less land. Cutting-edge technologies, including genetic engineering, can help to develop improved crop varieties and protect natural resources. In spite of the potential for genetically-modified (GM) crops to make crop production more efficient, they remain a polarizing issue due to safety concerns. This paper provides an overview of the risk assessment process. The safety of Bacillus thuringiensis (Bt) proteins is used as an example for how risk assessment is applied to GM crops. Risks associated with GM crops have proven to be low to non-existent. Developing countries ...


Analyzing Large Workers’ Compensation Claims Using Generalized Linear Models And Monte Carlo Simulation, Fatemeh Davoudi Kakhki, Steven A. Freeman, Gretchen A. Mosher Dec 2018

Analyzing Large Workers’ Compensation Claims Using Generalized Linear Models And Monte Carlo Simulation, Fatemeh Davoudi Kakhki, Steven A. Freeman, Gretchen A. Mosher

Agricultural and Biosystems Engineering Publications

Insurance practitioners rely on statistical models to predict future claims in order to provide financial protection. Proper predictive statistical modeling is more challenging when analyzing claims with lower frequency, but high costs. The paper investigated the use of predictive generalized linear models (GLMs) to address this challenge. Workers’ compensation claims with costs equal to or more than US$100,000 were analyzed in agribusiness industries in the Midwest of the USA from 2008 to 2016. Predictive GLMs were built with gamma, Weibull, and lognormal distributions using the lasso penalization method. Monte Carlo simulation models were developed to check the performance ...


Exploring School Foodservice Directors’ Intentions To Implement Farm-To-School Procurement Methods Considering Food Safety Practices, Sandra C. Curwood, Lakshman Rajagopal, Susan W. Arendt, Stephen Sapp Dec 2018

Exploring School Foodservice Directors’ Intentions To Implement Farm-To-School Procurement Methods Considering Food Safety Practices, Sandra C. Curwood, Lakshman Rajagopal, Susan W. Arendt, Stephen Sapp

Apparel, Events and Hospitality Management Publications

This study explored the intentions of foodservice directors' (FSD) who oversee Farm-to-School (F2S) programs to implement alternative procurement methods that better account for food safety practices. A web-based questionnaire was distributed to 864 California school FSDs with 136 (15.7%) usable surveys returned. Findings revealed that although FSDs understand the importance of food safety training and have confidence in their ability to manage produce safety practices, they express little intention to change their procurement practices. This finding might indicate a need for more resources and supportive policies.


Insights Into The Evolution Of The New World Diploid Cottons (Gossypium, Subgenus Houzingenia) Based On Genome Sequencing, Corrinne E. Grover, Mark A. Arick Ii, Adam Thrash, Justin L. Conover, William S. Sanders, Daniel G. Peterson, James E. Frelichowski, Jodi A. Scheffler, Brian E. Scheffler, Jonathan F. Wendel Nov 2018

Insights Into The Evolution Of The New World Diploid Cottons (Gossypium, Subgenus Houzingenia) Based On Genome Sequencing, Corrinne E. Grover, Mark A. Arick Ii, Adam Thrash, Justin L. Conover, William S. Sanders, Daniel G. Peterson, James E. Frelichowski, Jodi A. Scheffler, Brian E. Scheffler, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

We employed phylogenomic methods to study molecular evolutionary processes and phylogeny in the geographically widely dispersed New World diploid cottons (Gossypium, subg. Houzingenia). Whole genome resequencing data (average of 33X genomic coverage) were generated to reassess the phylogenetic history of the subgenus and provide a temporal framework for its diversification. Phylogenetic analyses indicate that the subgenus likely originated following trans-oceanic dispersal from Africa about 6.6 mya, but that nearly all of the biodiversity evolved following rapid diversification in the mid-Pleistocene (0.5-2.0 mya), with multiple long-distance dispersals required to account for range expansion to Arizona, the Galapagos Islands ...


Writing Ourselves Into Existence: Healing Through Collaborative Curriculum Development, Bianca Ivette Laureano, Sara C. Flowers Drph Nov 2018

Writing Ourselves Into Existence: Healing Through Collaborative Curriculum Development, Bianca Ivette Laureano, Sara C. Flowers Drph

Journal of Critical Thought and Praxis

Here we offer an open exchange / evaluation of our experience as facilitator and editor (Bianca) and writer and collaborator (Sara) during the inaugural Women of Color Sexual Health Network Curriculum Lab which took place November 2017 in New Orleans, LA. In two months, 7 women and femmes of color who are sexuality educators wrote a robust curriculum for our communities that centers pleasure, social emotional learning competencies as early Freedom Schools implemented, sex and pleasure positive, using an intersectional framework and praxis, disability justice framework, inclusive of LGBTQ communities, and does not assume HIV negative status. This is one of ...


Handwriting At Different Paces And Sizes With Visual Cues In Persons With Parkinson’S Disease, Andrew Zaman, Elizabeth L. Stegemoller Nov 2018

Handwriting At Different Paces And Sizes With Visual Cues In Persons With Parkinson’S Disease, Andrew Zaman, Elizabeth L. Stegemoller

Kinesiology Publications

Background: Persons with Parkinson’s disease (PD) typically have small handwriting, especially when writing faster and/or larger. However, visual cues can help persons with PD increase their handwriting size. This study tested if lined paper would improve handwriting in persons with PD, even when writing faster and/or larger. Secondarily, we wanted determine if persons with PD perceived handwriting as stressful, and if perceived stress was associated with writing performance.

Methods: The study included 22 subjects with Parkinson’s disease and 11 age-gender-matched controls. Participants completed eight trials (2 × 2 × 2) of printing a “P” and “d”, at a ...


Genotypic Variation In Anthocyanins, Phenolic Compounds, And Antioxidant Activity In Cob And Husk Of Purple Field Corn, Ponsawan Khamphasan, Khomsorn Lomthaisong, Bhornchai Harakotr, Danupol Ketthaisong, Marvin Paul Scott, Kamol Lertrat, Bhalang Suriharn Nov 2018

Genotypic Variation In Anthocyanins, Phenolic Compounds, And Antioxidant Activity In Cob And Husk Of Purple Field Corn, Ponsawan Khamphasan, Khomsorn Lomthaisong, Bhornchai Harakotr, Danupol Ketthaisong, Marvin Paul Scott, Kamol Lertrat, Bhalang Suriharn

Agronomy Publications

Information on phytochemicals in the cob and husk of field corn is important for the use of corn waste in the production of value-added corn products. The objectives of this study were to evaluate the variation in monomeric anthocyanin content (MAC), total phenolic content (TPC), and antioxidant activity, as determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and Trolox equivalent antioxidant capacity (TEAC) in 53 purple field corn genotypes, and to study the correlations of these traits with color parameters. Fifty-three corn genotypes were planted in a randomized complete block design with three replications in two locations in the ...


Haplotype Loci Under Selection In Canadian Durum Wheat Germplasm Over 60 Years Of Breeding: Association With Grain Yield, Quality Traits, Protein Loss, And Plant Height, Amidou N'Diaye, Jemanesh K. Haile, Kirby T. Nilsen, Sean Walkowiak, Yuefeng Ruan, Asheesh K. Singh, Fran R. Clarke, John M. Clarke, Curtis J. Pozniak Nov 2018

Haplotype Loci Under Selection In Canadian Durum Wheat Germplasm Over 60 Years Of Breeding: Association With Grain Yield, Quality Traits, Protein Loss, And Plant Height, Amidou N'Diaye, Jemanesh K. Haile, Kirby T. Nilsen, Sean Walkowiak, Yuefeng Ruan, Asheesh K. Singh, Fran R. Clarke, John M. Clarke, Curtis J. Pozniak

Agronomy Publications

Durum wheat was introduced in the southern prairies of western Canada in the late nineteenth century. Breeding efforts have mainly focused on improving quality traits to meet the pasta industry demands. For this study, 192 durum wheat lines were genotyped using the Illumina 90K Infinium iSelect assay, and resulted in a total of 14,324 polymorphic SNPs. Genetic diversity changed over time, declining during the first 20 years of breeding in Canada, then increased in the late 1980s and early 1990s. We scanned the genome for signatures of selection, using the total variance Fst-based outlier detection method (Lositan), the hierarchical ...


Perennial Biomass Crop Establishment, Community Characteristics, And Productivity In The Upper Us Midwest: Effects Of Cropping Systems Seed Mixtures And Biochar Applications, Catherine L. Bonin, Rivka B. Fidel, Chumki Banik, David A. Laird, Robert Mitchell, Emily A. Heaton Nov 2018

Perennial Biomass Crop Establishment, Community Characteristics, And Productivity In The Upper Us Midwest: Effects Of Cropping Systems Seed Mixtures And Biochar Applications, Catherine L. Bonin, Rivka B. Fidel, Chumki Banik, David A. Laird, Robert Mitchell, Emily A. Heaton

Agronomy Publications

Native perennial plants have potential as bioenergy feedstocks, but their use is currently limited by relatively long establishment times and low biomass yields. Some research suggests that incorporating plant species diversity and applying biochar as a soil amendment might alleviate these limitations by creating a more resilient crop and soil system. The objective of this research was to investigate how 1) seeded plant diversity and 2) biochar soil amendments interact to affect the establishment, yield, and plant species composition of biomass cropping systems during the first four years of growth on productive soils. We measured species emergence, cover, peak and ...


Microbial Community Structure And Functions Differ Between Native And Novel (Exotic-Dominated) Grassland Ecosystems In An 8-Year Experiment, Aleksandra Checinska Sielaff, Racheal N. Upton, Kirsten S. Hofmockel, Xia Xu, H. Wayne Polley, Brian J. Wilsey Nov 2018

Microbial Community Structure And Functions Differ Between Native And Novel (Exotic-Dominated) Grassland Ecosystems In An 8-Year Experiment, Aleksandra Checinska Sielaff, Racheal N. Upton, Kirsten S. Hofmockel, Xia Xu, H. Wayne Polley, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

A Grasslands dominated by non-native (exotic) spe- cies have replaced purely native-dominated areas in many parts of the world forming ‘novel’ ecosystems. Altered precipitation patterns are predicted to exacerbate this trend. It is still poorly understood how soil microbial communities and their functions differ between high diversity native- and low diversity exotic-dominated sites and how altered precipitation will impact this difference.

Methods We sampled 64 experimental grassland plots in central Texas with plant species mixtures of either all native or all exotic species; half with summer irrigation. We tested how native vs. exotic plant species mixtures and summer irrigation affected ...


Optimization Of Time-Weighted Average Air Sampling By Solid-Phase Microextraction Fibers Using Finite Element Analysis Software, Bulat Kenessov, Jacek A. Koziel, Nassiba Baimatova, Olga P. Demyanenko, Miras Derbissalin Oct 2018

Optimization Of Time-Weighted Average Air Sampling By Solid-Phase Microextraction Fibers Using Finite Element Analysis Software, Bulat Kenessov, Jacek A. Koziel, Nassiba Baimatova, Olga P. Demyanenko, Miras Derbissalin

Agricultural and Biosystems Engineering Publications

Determination of time-weighted average (TWA) concentrations of volatile organic compounds (VOCs) in air using solid-phase microextraction (SPME) is advantageous over other sampling techniques, but is often characterized by insufficient accuracies, particularly at longer sampling times. Experimental investigation of this issue and disclosing the origin of the problem is problematic and often not practically feasible due to high uncertainties. This research is aimed at developing the model of the TWA extraction process and optimization of TWA air sampling by SPME using finite element analysis software (COMSOL Multiphysics, Burlington, MA, USA). It was established that sampling by porous SPME coatings with high ...


High Density Genetic Mapping Of Fusarium Head Blight Resistance Qtl In Tetraploid Wheat, Ehsan Sari, Samia Berraies, Ron E. Knox, Asheesh K. Singh, Yuefeng Ruan, Richard D. Cuthbert, Curtis J. Pozniak, Maria Antonia Henriquez, Santosh Kumar, Andrew J. Burt, Amidou N'Diaye, David J. Konkin, Adrian L. Cabral, Heather L. Campbell, Krystalee Wiebe, Janet Condie, Prabhath Lokuruge, Brad Meyer, George Fedak, John M. Clarke, Daryl J. Somers, Perre R. Fobert Oct 2018

High Density Genetic Mapping Of Fusarium Head Blight Resistance Qtl In Tetraploid Wheat, Ehsan Sari, Samia Berraies, Ron E. Knox, Asheesh K. Singh, Yuefeng Ruan, Richard D. Cuthbert, Curtis J. Pozniak, Maria Antonia Henriquez, Santosh Kumar, Andrew J. Burt, Amidou N'Diaye, David J. Konkin, Adrian L. Cabral, Heather L. Campbell, Krystalee Wiebe, Janet Condie, Prabhath Lokuruge, Brad Meyer, George Fedak, John M. Clarke, Daryl J. Somers, Perre R. Fobert

Agronomy Publications

Breeding for Fusarium head blight (FHB) resistance in durum wheat is complicated by the quantitative trait expression and narrow genetic diversity of available resources. High-density mapping of the FHB resistance quantitative trait loci (QTL), evaluation of their co-localization with plant height and maturity QTL and the interaction among the identified QTL are the objectives of this study. Two doubled haploid (DH) populations, one developed from crosses between Triticum turgidum ssp. durum lines DT707 and DT696 and the other between T. turgidum ssp. durum cv. Strongfield and T. turgidum ssp. carthlicum cv. Blackbird were genotyped using the 90K Infinium iSelect chip ...


A Qualitative Investigation Of Farmer And Rancher Perceptions Of Trees And Woody Biomass Production On Marginal Agricultural Land, Ashley Hand, John Tyndall Oct 2018

A Qualitative Investigation Of Farmer And Rancher Perceptions Of Trees And Woody Biomass Production On Marginal Agricultural Land, Ashley Hand, John Tyndall

Natural Resource Ecology and Management Publications

Bioenergy produced from perennial feedstocks such as woody biomass could serve as an opportunity to strengthen local and regional economies and also jointly produce various environmental services. In order to assess the potential for biomass- based bioenergy, it’s essential to characterize the interest that potential biomass suppliers have in such an endeavor. In the U.S. Great Plains region, this largely means assessing relevant perceptions of farmers and ranchers. We conducted a series of farmer and rancher oriented focus groups in North Dakota, South Dakota, Nebraska and Kansas to qualitatively explore opinions about the role that trees can play ...


Aac Viewfield Hard Red Spring Wheat, R. D. Cuthbert, R. M. Depauw, A. K. Singh, B. Mccallum, T. Fetch Oct 2018

Aac Viewfield Hard Red Spring Wheat, R. D. Cuthbert, R. M. Depauw, A. K. Singh, B. Mccallum, T. Fetch

Agronomy Publications

AAC Viewfield hard red spring wheat (Triticum aestivum L.) has grain yield significantly higher than the check cultivars Katepwa and Lillian and is similar to Carberry. AAC Viewfield matures significantly later than Katewpa and Lillian but is similar to Carberry. AAC Viewfield has an awned spike, a low lodging score indicative of strong straw, and significantly shorter plant stature than all checks. AAC Viewfield expressed resistance to prevalent races of yellow rust and stem rust, moderate resistance to leaf rust and common bunt, and intermediate resistance to Fusarium head blight. AAC Viewfield has quality attributes within the range of the ...


Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen Oct 2018

Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen

Mechanical Engineering Publications

Flexible graphene electronics are rapidly gaining interest, but their widespread implementation has been impeded by challenges with ink preparation, ink printing, and post-print annealing processes. Laser-induced graphene (LIG) promises a facile alternative by creating flexible graphene electronics on polyimide substrates through a one-step laser writing fabrication method. Herein we demonstrate the use of LIG, created through a low-cost UV laser, for electrochemical ion selective sensing of plant-available nitrogen (i.e., both ammonium and nitrate ions: NH4+ and NO3-) in soil samples. The laser used to create the LIG was operated at distinct pulse rates (10, 20, 30, 40, and 50 ...


Delayed Trait Development And The Convergent Evolution Of Shell Kinesis In Turtles, Gerardo A. Cordero, Kevin Quinteros, Fredric J. Janzen Oct 2018

Delayed Trait Development And The Convergent Evolution Of Shell Kinesis In Turtles, Gerardo A. Cordero, Kevin Quinteros, Fredric J. Janzen

Ecology, Evolution and Organismal Biology Publications

Developmental processes are foundational to clarifying the causes of convergent evolution. Here, we show how a key convergently evolving trait is slowly “acquired” in growing turtles. Adaptive morphological change tends to originate late in turtle ontogeny, owing to design constraints imposed by the shell. We investigated this trend by examining derived patterns of shell formation associated with the multiple (≥ 8) origins of shell closure (kinesis) in smallbodied turtles. Using box turtles as a model, we demonstrate that the flexible hinge joint required for shell kinesis differentiates gradually and via extensive repatterning of shell tissue. Disproportionate changes in shell shape and ...


Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel Oct 2018

Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel

Agricultural and Biosystems Engineering Publications

Microbial mechanisms controlling cellulose degradation in soil habitats remains a critical knowledge gap in understanding and modeling terrestrial carbon-cycling. We investigated land management and soil micro-habitat influences on soil bacterial communities and distribution of cellulose-degrading enzyme genes in three bioenergy cropping systems (corn, prairie, and fertilized prairie). Within the soil, aggregates have been examined as potential micro- habitats with specific characteristics influencing resource partitioning and regulation, thus we also investigated genes associated with cellulose degradation within soil aggregate fractions from the fertilized prairie system. Soil bacterial communities and carbon-cycling gene presence varied across land management and soil microhabitats. Examination of ...


A Phage-Based Assay For The Rapid, Quantitative, And Single Cfu Visualization Of E. Coli (Ecor #13) In Drinking Water, Troy C. Hinkely, S. Singh, Spencer Garing, Anne-Laure M. Le Ny, Kevin P. Nichols, Joseph E. Peters, Joey N. Talbert, Sam R. Nugen Oct 2018

A Phage-Based Assay For The Rapid, Quantitative, And Single Cfu Visualization Of E. Coli (Ecor #13) In Drinking Water, Troy C. Hinkely, S. Singh, Spencer Garing, Anne-Laure M. Le Ny, Kevin P. Nichols, Joseph E. Peters, Joey N. Talbert, Sam R. Nugen

Food Science and Human Nutrition Publications

Drinking water standards in the United States mandate a zero tolerance of generic E. coli in 100mL of water. The presence of E. coli in drinking water indicates that favorable environmental conditions exist that could have resulted in pathogen contamination. Therefore, the rapid and specifc enumeration of E. coli in contaminated drinking water is critical to mitigate signifcant risks to public health. To meet this challenge, we developed a bacteriophage-based membrane fltration assay that employs novel fusion reporter enzymes to fully quantify E. coli in less than half the time required for traditional enrichment assays. A luciferase and an alkaline ...


Nanoparticle Microarray For High-Throughput Microbiome Metabolomics Using Matrix-Assisted Laser Desorption Ionization Mass Spectrometry, Rebecca L. Hansen, Maria Emilia Duenas, Torey Looft, Young Jin Lee Oct 2018

Nanoparticle Microarray For High-Throughput Microbiome Metabolomics Using Matrix-Assisted Laser Desorption Ionization Mass Spectrometry, Rebecca L. Hansen, Maria Emilia Duenas, Torey Looft, Young Jin Lee

Chemistry Publications

A high-throughput matrix-assisted laser desorption/ionization mass spectrometry (MALDI)-MS-based metabolomics platform was developed using a pre-fabricated microarray of nanoparticles and organic matrices. Selected organic matrices, inorganic nanoparticle (NP) suspensions, and sputter coated metal NPs, as well as various additives, were tested for metabolomics analysis of the turkey gut microbiome. Four NPs and one organic matrix were selected as the optimal matrix set: α-cyano-4-hydroycinnamic acid, Fe3O4 and Au NPs in positive ion mode with 10 mM sodium acetate, and Cu and Ag NPs in negative ion mode with no additive. Using this set of five matrices, over two thousand unique ...


Legacy Effects Of Long-Term Nitrogen Fertilizer Application On The Fate Of Nitrogen Fertilizer Inputs In Continuous Maize, Hanna J. Poffenbarger, John E. Sawyer, Daniel W. Barker, Daniel C. Olk, Johan Six, Michael J. Castellano Oct 2018

Legacy Effects Of Long-Term Nitrogen Fertilizer Application On The Fate Of Nitrogen Fertilizer Inputs In Continuous Maize, Hanna J. Poffenbarger, John E. Sawyer, Daniel W. Barker, Daniel C. Olk, Johan Six, Michael J. Castellano

Agronomy Publications

Nitrogen fertilizer management can impact soil organic C (SOC) stocks in cereal-based cropping systems by regulating crop residue inputs and decomposition rates. However, the impact of long-term N fertilizer management, and associated changes in SOC quantity and quality, on the fate of N fertilizer inputs is uncertain. Using two 15-year N fertilizer rate experiments on continuous maize (Zea mays L.) in Iowa, which have generated gradients of SOC, we evaluated the legacy effects of N fertilizer inputs on the fate of added N. Across the historical N fertilizer rates, which ranged from 0 to 269 kg N ha−1 yr ...


Deep Learning For Plant Stress Phenotyping: Trends And Future Perspectives, Asheesh Kumar Singh, Baskar Ganapathysubramanian, Soumik Sarkar, Arti Singh Oct 2018

Deep Learning For Plant Stress Phenotyping: Trends And Future Perspectives, Asheesh Kumar Singh, Baskar Ganapathysubramanian, Soumik Sarkar, Arti Singh

Agronomy Publications

Deep learning (DL), a subset of machine learning approaches, has emerged as a versatile tool to assimilate large amounts of heterogeneous data and provide reliable predictions of complex and uncertain phenomena. These tools are increasingly being used by the plant science community to make sense of the large datasets now regularly collected via high-throughput phenotyping and genotyping. We review recent work where DL principles have been utilized for digital image–based plant stress phenotyping. We provide a comparative assessment of DL tools against other existing techniques, with respect to decision accuracy, data size requirement, and applicability in various scenarios. Finally ...


Multiple Facets Of Biodiversity Drive The Diversity–Stability Relationship, Dylan Craven, H. Wayne Polley, Brian Wilsey, Et Al. Oct 2018

Multiple Facets Of Biodiversity Drive The Diversity–Stability Relationship, Dylan Craven, H. Wayne Polley, Brian Wilsey, Et Al.

Ecology, Evolution and Organismal Biology Publications

A substantial body of evidence has demonstrated that biodiversity stabilizes ecosystem functioning over time in grassland ecosystems. However, the relative importance of different facets of biodiversity underlying the diversity–stability relationship remains unclear. Here we use data from 39 grassland biodiversity experiments and structural equation modelling to investigate the roles of species richness, phylogenetic diversity and both the diversity and community-weighted mean of functional traits representing the ‘fast–slow’ leaf economics spectrum in driving the diversity–stability relationship. We found that high species richness and phylogenetic diversity stabilize biomass production via enhanced asynchrony in the performance of co-occurring species. Contrary ...


Multi-Objective Optimized Genomic Breeding Strategies For Sustainable Food Improvement, Deniz Akdemir, William D, Beavis, Roberto Fritsche-Neto, Asheesh K. Singh, Julio Isidro-Sánchez Sep 2018

Multi-Objective Optimized Genomic Breeding Strategies For Sustainable Food Improvement, Deniz Akdemir, William D, Beavis, Roberto Fritsche-Neto, Asheesh K. Singh, Julio Isidro-Sánchez

Agronomy Publications

The purpose of breeding programs is to obtain sustainable gains in multiple traits while controlling the loss of genetic variation. The decisions at each breeding cycle involve multiple, usually competing, objectives; these complex decisions can be supported by the insights that are gained by applying multi-objective optimization principles to breeding. The discussion in this manuscript includes the definition of several multi-objective optimized breeding approaches within the phenotypic or genomic breeding frameworks and the comparison of these approaches with the standard multi-trait breeding schemes such as tandem selection, independent culling and index selection. Proposed methods are demonstrated with two empirical data ...


A Novel Multirobot System For Plant Phenotyping, Tianshuang Gao, Hamid Emadi, Homagni Saha, Jiaoping Zhang, Alec Lofquist, Arti Singh, Baskar Ganapathysubramanian, Soumik Sarkar, Asheesh K. Singh, Sourabh Bhattacharya Sep 2018

A Novel Multirobot System For Plant Phenotyping, Tianshuang Gao, Hamid Emadi, Homagni Saha, Jiaoping Zhang, Alec Lofquist, Arti Singh, Baskar Ganapathysubramanian, Soumik Sarkar, Asheesh K. Singh, Sourabh Bhattacharya

Mechanical Engineering Publications

Phenotypic studies require large datasets for accurate inference and prediction. Collecting plant data in a farm can be very labor intensive and costly. This paper presents the design, architecture (hardware and software) and deployment of a multi-robot system for row crop field data collection. The proposed system has been deployed in a soybean research farm at Iowa State University.


Conserved Genes Underlie Phenotypic Plasticity In An Incipiently Social Bee, S. M. Rehan, K. M. Glastad, M. A. Steffen, C. R. Fay, B. G. Hunt, A. L. Toth Sep 2018

Conserved Genes Underlie Phenotypic Plasticity In An Incipiently Social Bee, S. M. Rehan, K. M. Glastad, M. A. Steffen, C. R. Fay, B. G. Hunt, A. L. Toth

Ecology, Evolution and Organismal Biology Publications

Despite a strong history of theoretical work on the mechanisms of social evolution, relatively little is known of the molecular genetic changes that accompany transitions from solitary to eusocial forms. Here we provide the first genome of an incipiently social bee that shows both solitary and social colony organization in sympatry, the Australian carpenter bee Ceratina australensis. Through comparative analysis, we provide support for the role of conserved genes and cis-regulation of gene expression in the phenotypic plasticity observed in nest-sharing, a rudimentary form of sociality. Additionally, we find that these conserved genes are associated with caste differences in ...


Conservation Agriculture Practices Increase Potentially Mineralizable Nitrogen: A Meta-Analysis, Navreet K. Mahal, Michael J. Castellano, Fernando E. Miguez Sep 2018

Conservation Agriculture Practices Increase Potentially Mineralizable Nitrogen: A Meta-Analysis, Navreet K. Mahal, Michael J. Castellano, Fernando E. Miguez

Agronomy Publications

Potentially mineralizable nitrogen (PMN) is considered an important indicator of soil health. Cropping systems management can affect PMN. However, the effect size and relationship with crop yield across specific management practices remain uncertain. We conducted a quantitative review to understand how conservation agriculture management practices affect PMN including N fertilizer application, cropping system diversity, and tillage system as well as the relationship of crop yield with PMN. Data were extracted from 43 studies published in peer-reviewed journals, providing 494 paired comparisons of PMN and 26 paired comparisons of PMN and yield across selected crop management practices. In our meta-analysis, the ...


Improving Our Understanding Of Demographic Monitoring: Avian Breeding Productivity In A Tropical Dry Forest, M. Edye Kornegay, Amber N. M. Wiewel, Jaime A. Collazo, James F. Saracco, Stephen J. Dinsmore Sep 2018

Improving Our Understanding Of Demographic Monitoring: Avian Breeding Productivity In A Tropical Dry Forest, M. Edye Kornegay, Amber N. M. Wiewel, Jaime A. Collazo, James F. Saracco, Stephen J. Dinsmore

Natural Resource Ecology and Management Publications

The ratio of juvenile to adult birds in mist‐net samples is used to monitor avian productivity, but whether it is a “true” estimate of per capita productivity or an index proportional to productivity depends on whether capture probability is not age‐dependent (true estimate) or age difference in capture probability is consistent among years (index). Better understanding of the processes affecting age‐ and year‐specific capture probabilities is needed to advance the application of constant‐effort mist‐netting for monitoring and conservation, particularly in many tropical settings where capture rates are often low. We ranked members of the avian ...