An Integrated Crop- and Soil-Based Strategy for Variable-Rate Nitrogen Management in Corn

Nitrogen (N) management in cereal crops has been the subject of considerable research and debate for several decades. Historic N management practices have contributed to low nitrogen use efficiency (NUE). Low NUE can be caused by such things as poor synchronization between soil N supply and crop demand, uniform application rates of fertilizer N to spatially variable landscapes, and failure to account for temporally variable influences on soil N supply and crop N need. Active canopy reflectance sensors and management zones (MZ) have been studied separately as possible plant- and soil-based N management tools to increase NUE. Recently, some have suggested that the integration of these two approaches would provide a more robust N management strategy that could more effectively account for soil and plant effects on crop N need. For this reason, the goal of this research was to develop an N application strategy that would account for spatial variability in soil properties and use active canopy reflectance sensors to determine in-season, on-the-go N fertilizer rates, thereby increasing NUE and economic return for producers over current N management practices. To address this overall goal, a series of studies were conducted to better understand active canopy sensor use and explore the possibility of integrating spatial soil data with active canopy sensors. Sensor placement to assess crop N status was first examined. It was found that the greatest reduction in error over sensing each individual row for a hypothetical 24-row applicator was obtained with 2-3 sensors estimating an average chlorophyll index for the entire boom width. Next, use of active sensor-based soil organic matter (OM) estimation was compared to more conventional aerial image-based soil OM estimation. By adjusting regression intercept values for each field, OM could be predicted using either a single sensor or image data layer. The final study consisted of validation of the active sensor algorithm developed by Solari (2006), identification of soil variables for MZ delineation, and the possible integration of MZ and active sensors for N application. Crop response (sensor measured sufficiency index and yield) had the highest correlation with soil optical reflectance readings in sandy fields and with apparent soil electrical conductivity in silt loam fields with eroded slopes. Therefore, using these soil variables to delineate MZ allowed characterization of spatial patterns in both in-season crop response (sufficiency index) and yield. Compared to uniform N application, integrating MZ and sensor-based N application resulted in substantial N savings (~40-120 kg ha-1) and increases in partial factor productivity (~13-75 kg grain (kg N applied)-1) for fine-textured soils with eroded slopes. However, for coarser texture soils the current sensor-based N application algorithm may require further calibration, and for fields with no spatial variability there appears to be no benefit to using the algorithm. Collectively, results from these studies show promise for integrating active sensor-based N application and static soil-based MZ to increase NUE and economic return for producers over current N management strategies, but further research is needed to explore how best to integrate these two N management strategies

An environmental assessment of sensor-based variable-rate nitrogen management in corn

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file viewed on (June 26, 2007)Includes bibliographical references.Thesis (M.S.) University of Missouri-Columbia 2006.Dissertations, Academic -- University of Missouri--Columbia -- Agronomy.Nitrogen (N) fertilizer unused by the crop is left to the fate of the processes of the N cycle, and can eventually lead to nitrate contamination of surface and ground waters. In order to address this problem, various methods have been used to try to account for spatial variability of N within agricultural fields. One approach to account for this variability and thereby reduce nitrate pollution is in-season site-specific N application according to economic optimal N rate (EONR). Recently, active-light reflectance sensors have been tested for mid-season, on-the-go N fertilizer application in corn. This 2004 and 2005 study was conducted on 12 Missouri producer corn fields to (1) evaluate the relationship between EONR and active-light reflectance sensor readings, and (2) evaluate the relationship between environmental measurements and EONR. Measurements included EONR, crop N yield efficiency (YE), N fertilizer recovery efficiency (NFRE), and post-harvest soil inorganic N levels. In 2004, EONR was significantly related to active-light sensor indices, but with regression model coefficients of determination (r[superscript 2]) [less than or equal to] 0.35 for all sensor indices evaluated. Prediction of EONR improved (r[superscript 2] = 0.47) when soil electrical conductivity was added to the model. A relationship between EONR and the indices could not be established for 2005 data. In 2004, YE at EONR was not the same between fields, and ranged from 19-47 kg grain (kg N)-1. As N rate approached EONR, both YE and NFRE declined, while post-harvest inorganic N levels increased. These preliminary results show promise for using active-light reflectance sensors to achieve EONR and reduce N loss off fields

Characteristics of Community Service Programs and Probationers in Texas

As a criminal sanction, community service involves unpaid labor on the part of convicted criminal offenders. Community service was created as an alternative to incarceration for low-level offenders. It now appears, however, that community service is rarely used as a true alternative to prison, but rather as an added condition of probation. The body of research on community service in the United States is modest, so relatively little is known about its characteristics and administration. Data were attained from 88 Texas probation professionals via self-administered written surveys in an effort to gather information about the use of community service as a criminal sanction in Texas. Frequency distribution analyses identified characteristics of both community service programs and offender participants in Texas

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

Integrated pest management (IPM) for the cereal leaf beetle in Washington State

This bulletin describes how to identify the cereal leaf beetle (Oulema melanopus) and discusses its biology. Scouting techniques and economic thresholds are outlined, along with cultural management methods and optimal times to apply insecticide, if needed. It also discusses the most effective method of control--biocontrol using wasps that only parasitize and kill the cereal leaf beetle. Growers may encourage these free biocontrol agents to multiply in their fields by maintaining a simple insectary. Worksheets and a decision chart are included to help integrate all the decision processes

The complete mitochondrial genome of Dascyllus trimaculatus (Rüppell, 1829)

Damselfishes (family Pomacentridae) comprise approximately 400 species that play an important ecological role in temperate and coral reefs. Here, for the first time, we assemble and annotate the mitochondrial genome of Dascyllus trimaculatus, the three-spot dascyllus, a planktivorous damselfish that primarily recruits in anemones. The circular genome of D. trimaculatus is 16,967 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a control region. Gene arrangement and codon usage is similar to reported mitochondrial genomes of other damselfish genera, and a phylogenetic analysis of a set of damselfish representatives is consistent with known evolutionary analyses

Chromosome-level genome of the three-spot damselfish, Dascyllus trimaculatus

Damselfishes (Family: Pomacentridae) are a group of ecologically important, primarily coral reef fishes that include over 400 species. Damselfishes have been used as model organisms to study recruitment (anemonefishes), the effects of ocean acidification (spiny damselfish), population structure, and speciation (Dascyllus). The genus Dascyllus includes a group of small-bodied species, and a complex of relatively larger bodied species, the Dascyllus trimaculatus species complex that is comprised of several species including D. trimaculatus itself. The three-spot damselfish, D. trimaculatus, is a widespread and common coral reef fish species found across the tropical Indo-Pacific. Here, we present the first-genome assembly of this species. This assembly contains 910 Mb, 90% of the bases are in 24 chromosome-scale scaffolds, and the Benchmarking Universal Single-Copy Orthologs score of the assembly is 97.9%. Our findings confirm previous reports of a karyotype of 2n = 47 in D. trimaculatus in which one parent contributes 24 chromosomes and the other 23. We find evidence that this karyotype is the result of a heterozygous Robertsonian fusion. We also find that the D. trimaculatus chromosomes are each homologous with single chromosomes of the closely related clownfish species, Amphiprion percula. This assembly will be a valuable resource in the population genomics and conservation of Damselfishes, and continued studies of the karyotypic diversity in this clade

Controlling assembly of helical polypeptides via PEGylation strategies

Recent studies in our laboratories have demonstrated that a helical polypeptide (17H6), equipped with a histidine tag and a helical alanine-rich, glutamic-acid-containing domain, exhibits pH-responsive assembly behavior useful in the production of polymorphological nanostructures. In this study, the histidine tag in these polypeptides was replaced by polyethylene glycol (PEG) with different molecular masses (5 kDa, or 10 kDa), and the self-association behavior of 17H6 and the PEGylated conjugates was characterized via dynamic light scattering (DLS), small angle neutron scattering (SANS), and cryogenic transmission electron microscopy (cryo-TEM). DLS experiments illustrated that the polypeptide and its PEG-conjugates undergo reversible assembly under acidic conditions, suggesting that the aggregation state of the polypeptide and the conjugates is controlled by the charged state of the glutamic acid residues. Nanoscale aggregates were detected at polypeptide/conjugate concentrations as low as 20 μM (∼0.3-0.5 mg ml -1) at physiological and ambient temperatures. Scattering and microscopy results showed that the size, the aggregation number, and the morphology of the aggregates can be tuned by the size and the nature of the hydrophilic tag. This tunable nature of the morphology of the aggregates, along with their low critical aggregation concentration, suggests that PEG-alanine-rich polypeptide conjugates may be useful as drug delivery vehicles in which the alanine-rich block serves as a drug attachment domain.National Institutes of Health (NIH); National Center for Research Resources (NCRR) (1-P20-RR017716; 1-RO1-EB006006; P30-RR031160; National Aeronautics and Space Administration (NA68-01923); Center for Neutron Science at University of Delaware (70NANB7H6178