Molecular and Historical Aspects of Corn Belt Dent Diversity

Tens-of-thousands of open-pollinated cultivars of corn (Zea mays L.) are being maintained in germplasm banks. Knowledge of the amount and distribution of genetic variation within and among accessions can aid end users in choosing among them. We estimated molecular genetic variation and looked for influences of pedigree, adaptation, and migration in the genetic makeup of conserved Corn-Belt Dent-related germplasm. Plants sampled from 57 accessions representing Corn-Belt Dents, Northern Flints, Southern Dents, plus 12 public inbreds, were genotyped at 20 simple sequence repeat (SSR) loci. For 47 of the accessions, between 5 and 23 plants per accession were genotyped (mean = 9.3). Mean number of alleles per locus was 6.5 overall, 3.17 within accessions, and 3.20 within pooled inbreds. Mean gene diversity was 0.53 within accessions and 0.61 within pooled inbreds. Open-pollinated accessions showed a tendency toward inbreeding (FIS = 0.09), and 85% of genetic variation was shared among them. A Fitch-Margoliash tree strongly supported the distinctiveness of flint from dent germplasm but did not otherwise reveal evidence of genetic structure. Mantel tests revealed significant correlations between genetic distance and geographical (r = 0.54, P= 0.04) or maturity zone (r = 0.33, P = 0.03) distance only if flint germplasm was included in the analyses. A significant correlation (r = 0.76, P \u3c 0.01) was found between days to pollen shed and maturity zone of accession origin. Pedigree, rather than migration or selection, has most influenced the genetic structure of the extant representatives of the open-pollinated cultivars at these SSR loci

TRY plant trait database – enhanced coverage and open access

Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

System Test Methodology Vol. I

Prepared for: Naval Air Development Center Warminster, PennsylvaniaThe Naval Postgraduate School has conducted a research project during the period 30 June 1974 to 30 June 1975, entitled System Test Methodology under the sponsorship of the Naval Air Development Center. A progress report was submitted on 15 January 1975. The purpose of this project was to develop a methodology and tools for conducting system avionics or other complex hardware/ software systems. Two areas which received major emphasis were prototype testing and maintenance testing. A methodology for conducting prototype tests was developed. In addition, a simulation model was prepared for aiding the designer and tester in identifying and diagnosing faults which may occur during prototype testing. A maintenance testing methodology, which involves the use of tests to partition faults into subsets, was developed for identifying faults. In addition to the above areas, research was undertaken to develop models for investigating the relationship between error detection capability and program structure in computer software, using simulation and analytic approaches. The models would be employed during software design for identifying program structures with poor error characteristics and during test planning for the purpose of allocating test resources in accordance with error characteristics. In addition to the progress and final reports, computer program source decks and operating instructions for the system (prototype) test simulation and the software error detection (simulation and analytic) models have been provide to NADC. Lastly, three national conference proceedings publications and presentations and two Master of Science in Computer Science theses have resulted from this research project.Naval Air Development Center, Warminster, Pennsylvania.Approved for public release; distribution is unlimited

Development and Validation of an Orchestra Performance Rating Scale

The purpose of this study was to develop a factor-derived measure of orchestra performance achievement and to test its validity and reliability for the evaluation of secondary school orchestras. We assembled a pool of 49 statements used in evaluating middle and high school orchestra performance, paired them with a 9-point Likert-type scale, and asked 63 experienced orchestra teachers to evaluate 63 secondary school orchestras. Factor analyses on data from the 189 completed rating sheets identified seven factors: Ensemble, Left Hand, Position, Rhythm, Tempo, Presentation, and Bow. For the reduced scale, we chose 25 items with factor loadings greater than . 64, which showed Cronbach\u27s alphas ranging from . 73 to . 91. Two rounds of validation showed high correlations with MENC\u27s adjudication form and a ranking task; the initial factor structure was not exactly duplicated, indicating directions for future research