631 research outputs found

    Monte Carlo program for the transport of neutrons and gamma rays

    Get PDF
    Computer program computes transport of neutrons and gamma rays in complex geometries and fluxes averaged over specified regions and surfaces of the geometry

    Inspection gage for boss Patent

    Get PDF
    Gage for quality control of sealing surfaces of threaded bos

    MarkerMiner 1.0: a new application for phylogenetic marker development using angiosperm transcriptomes

    Get PDF
    Premise of the study: Targeted sequencing using next-generation sequencing (NGS) platforms offers enormous potential for plant systematics by enabling economical acquisition of multilocus data sets that can resolve difficult phylogenetic problems. However, because discovery of single-copy nuclear (SCN) loci from NGS data requires both bioinformatics skills and access to high-performance computing resources, the application of NGS data has been limited. Methods and Results: We developed MarkerMiner 1.0, a fully automated, open-access bioinformatic workflow and application for discovery of SCN loci in angiosperms. Our new tool identified as many as 1993 SCN loci from transcriptomic data sampled as part of four independent test cases representing marker development projects at different phylogenetic scales. Conclusions: MarkerMiner is an easy-to-use and effective tool for discovery of putative SCN loci. It can be run locally or via the Web, and its tabular and alignment outputs facilitate efficient downstream assessments of phylogenetic utility, locus selection, intron-exon boundary prediction, and primer or probe development

    Integrated pest management in the academic small greenhouse setting: A case study using Solanum spp. (Solanaceae).

    Get PDF
    Premise Botanical faculty and staff at academic institutions are often tasked with establishing and/or caring for plant collections held in small greenhouse facilities. Once plants are in place, an especially acute challenge is managing plant pest/pathogen populations. Integrated pest management (IPM) approaches are an excellent option, but few examples exist in the literature of successful programs that have been developed in academic small greenhouse settings. Methods and Results Over several years, we developed an IPM program for two small research greenhouses on the campus of a primarily undergraduate institution where hundreds of plants have been grown for studies in the genus Solanum. We here present a synopsis of the cultural, mechanical, physical, and biological controls used as part of our successful IPM strategy—including details on the efficacy of multiple predatory insects—with the hope of providing a model for sustainable pest management in the higher education environment. Conclusions IPM can be an effective strategy for maintaining healthy plant populations in small research greenhouses, but it requires a consistent investment of time and funding. A well‐cared‐for plant collection might help support numerous positive outcomes, including advances in faculty scholarship and opportunities for student learning and/or training

    A Foundational Population Genetics Investigation of the Sexual Systems of Solanum (Solanaceae) in the Australian Monsoon Tropics Suggests Dioecious Taxa May Benefit from Increased Genetic Admixture via Obligate Outcrossing

    Get PDF
    Solanum section Leptostemonum is an ideal lineage to test the theoretical framework regarding proposed evolutionary benefits of outcrossing sexual systems in comparison to cosexuality. Theoretically, non-cosexual taxa should support more genetic diversity within populations, experience less inbreeding, and have less genetic structure due to a restricted ability to self-fertilize. However, many confounding factors present challenges for a confident inference that inherent differences in sexual systems influence observed genetic patterns among populations. This study provides a foundational baseline of the population genetics of several species of different sexual systems with the aim of generating hypotheses of any factor—including sexual system—that influences genetic patterns. Importantly, results indicate that dioecious S. asymmetriphyllum maintains less genetic structure and greater admixture among populations than cosexual S. raphiotes at the same three locations where they co-occur. This suggests that when certain conditions are met, the evolution of dioecy may have proceeded as a means to avoid genetic consequences of self-compatibility and may support hypotheses of benefits gained through differential resource allocation partitioned across sexes. Arguably, the most significant finding of this study is that all taxa are strongly inbred, possibly reflective of a shared response to recent climate shifts, such as the increased frequency and intensity of the region’s fire regime

    Code wars: steganography, signals intelligence, and terrorism

    Get PDF
    This paper describes and discusses the process of secret communication known as steganography. The argument advanced here is that terrorists are unlikely to be employing digital steganography to facilitate secret intra-group communication as has been claimed. This is because terrorist use of digital steganography is both technically and operationally implausible. The position adopted in this paper is that terrorists are likely to employ low-tech steganography such as semagrams and null ciphers instead

    Effects of Backgrounding and Growing Programs on Beef Carcass Quality and Yield

    Get PDF
    Clearly, the future of the beef cattle industry in the United States depends on the quality of the product. The majority of calves are born in the spring; therefore, to have a consistent supply of feeders entering feedlots and to take advantage of forages, a variety of stocker programs exist. Cattle enter the feedlot at varying weights and ages and from different nutritional backgrounds, and this variation could produce differences in carcass quality. The economically important measures of carcass quality are yield grade and quality grade. They are directly related: as cattle fatten in the feedlot, both quality grade and yield grade increase. Because cattle are commercially fed to fat-constant end points, it is logical to make comparisons at equal fat end points. Then, marbling (percentage Choice) becomes the primary quality criterion. We analyzed data from 534 cattle serially slaughtered and found that the percentage grading Choice increased 12 ± 1 percentage units for each 1-mm increase in rib fat. Marbling score increased 30 units (200 = slight 00) for each 1-mm increase in fat. To determine the effect of rate of winter gain on carcass quality, 372 calves over 5 yr were wintered at .23 or .61 kg/d gain. When adjusted to equal rib fat after summer grazing and finishing, there was no difference in quality grade. To test the effect of summer gain on carcass quality, 418 calves over 7 yr were followed through the feedlot after gaining .57 or .84 kg/d on grass. When compared at equal rib fat, there was no difference in quality grade. Shear force values and consumer taste panels were used to evaluate steaks from 90 cattle from calf-fed and yearling production systems. Calf-feds were 14 mo of age at slaughter and yearlings were 19 or 21 mo. Each group was serially slaughtered. There was no effect of an additional .39 cm of rib fat on shear force, juiciness, tenderness, flavor, or overall palatability. Calf-feds were significantly more tender than yearlings, but the risk of an undesirable steak from yearlings was \u3c .2% based on shear force and \u3c 2.8% based on the consumer taste panel. If cattle are fed to a common rib fat end point, and within the range of rates of winter and summer gains reported herein, we conclude that the backgrounding program has little or no effect on marbling or carcass quality grade

    Comparison of Performance and Economics of a Long-yearling and Calf-fed System

    Get PDF
    Performance and economics of calf feeding and feeding long-yearlings was compared from University of Nebraska research conducted from 1996 to 2004. All calves in these studies were spring born and purchased the subsequent fall. The heaviest calves (292 ± 5 kg) were placed into the feedlot and fed an average of 168 d (calf-feds), whereas the lighter calves (239 ± 5 kg) were placed into a long-yearling system consisting of corn residue grazing followed by summer grazing before entering the feedlot for finishing. Long-yearlings were fed in the feedlot for an average of 90 d. At the beginning of the finishing period, long-yearlings were 143 kg heavier than calf-feds (P \u3c 0.01). Although daily DMI was greater for long-yearlings (P \u3c 0.01), calf-feds consumed more total DM during finishing (P \u3c 0.01). Long-yearlings had greater ADG compared with calf-feds during finishing (P \u3c 0.01); however, calf-feds were 18.7% more efficient (P \u3c 0.01). Long-yearlings were 38 kg heavier (P \u3c 0.01) than calf-feds and had 24 kg heavier hot carcass weight (P \u3c 0.01). Quality grade was not affected by production system (P \u3e 0.10); however, calf-feds had 0.15 cm greater fat thickness (P \u3c 0.01). Long-yearlings were more profitable than calf-feds (P \u3c 0.01) due to lower feed cost (P \u3c 0.01), yardage (P \u3c 0.01), and initial animal cost (P \u3c 0.01). However, long-yearlings had higher interest cost (P \u3c 0.01) and total cost (P = 0.02). Long-yearlings produced greater final BW leading to an improvement in profitability compared with calf-feds

    A Basic ddRADseq Two‐Enzyme Protocol Performs Well with Herbarium and Silica‐Dried Tissues across Four Genera

    Get PDF
    PREMISE: The ability to sequence genome-scale data from herbarium specimens would allow for the economical development of data sets with broad taxonomic and geographic sampling that would otherwise not be possible. Here, we evaluate the utility of a basic double-digest restriction site–associated DNA sequencing (ddRADseq) protocol using DNAs from four genera extracted from both silica-dried and herbarium tissue. METHODS: DNAs from Draba, Boechera, Solidago, and Ilex were processed with a ddRADseq protocol. The effects of DNA degradation, taxon, and specimen age were assessed. RESULTS: Although taxon, preservation method, and specimen age affected data recovery, large phylogenetically informative data sets were obtained from the majority of samples. DISCUSSION: These results suggest that herbarium samples can be incorporated into ddRADseq project designs, and that specimen age can be used as a rapid on-site guide for sample choice. The detailed protocol we provide will allow users to pursue herbariumbased ddRADseq projects that minimize the expenses associated with fieldwork and sample evaluation
    • 

    corecore