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Introduction The tobacco-specific nitrosamines (TSNAs) are an important group of carcinogens found in tobacco and tobacco smoke. To describe and characterize the levels of TSNAs in the Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013–2014), we present four biomarkers of TSNA exposure: N′-nitrosonornicotine, N′-nitrosoanabasine, N′-nitrosoanatabine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) which is the primary urinary metabolite of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Methods We measured total TSNAs in 11 522 adults who provided urine using automated solid-phase extraction coupled to isotope dilution liquid chromatography–tandem mass spectrometry. After exclusions in this current analysis, we selected 11 004 NNAL results, 10 753 N′-nitrosonornicotine results, 10 919 N′-nitrosoanatabine results, and 10 996 N′-nitrosoanabasine results for data analysis. Geometric means and correlations were calculated using SAS and SUDAAN. Results TSNA concentrations were associated with choice of tobacco product and frequency of use. Among established, every day, exclusive tobacco product users, the geometric mean urinary NNAL concentration was highest for smokeless tobacco users (993.3; 95% confidence interval [CI: 839.2, 1147.3] ng/g creatinine), followed by all types of combustible tobacco product users (285.4; 95% CI: [267.9, 303.0] ng/g creatinine), poly tobacco users (278.6; 95% CI: [254.9, 302.2] ng/g creatinine), and e-cigarette product users (6.3; 95% CI: [4.7, 7.9] ng/g creatinine). TSNA concentrations were higher in every day users than in intermittent users for all the tobacco product groups. Among single product users, exposure to TSNAs differed by sex, age, race/ethnicity, and education. Urinary TSNAs and nicotine metabolite biomarkers were also highly correlated. Conclusions We have provided PATH Study estimates of TSNA exposure among US adult users of a variety of tobacco products. These data can inform future tobacco product and human exposure evaluations and related regulatory activities.

Scientists who study large and charismatic megafauna have little trouble inspiring awe and love for their research subjects. As entomologists, we are often frustrated because we have the opposite experience. We are, however, keenly aware of one major advantage over our colleagues when interacting with the public: insects are everywhere. No one grows up without having some sort of interaction with insects. Insects are familiar, accessible, and often misunderstood. Misunderstanding has the potential to be converted into the mysterious and wonderful. Insects are a perfect tool to engage the public in science (Golick et al. 2010). As entomologists, we know that insects have the potential to reach out across and outside campus to engage faculty and community members from many backgrounds. Here, we provide an example of intersecting art and insects in a central location on a small college campus as a way to engage the public with insect biology. Libraries are a repository for print and electronic information, but they also serve important roles as a community center, cultural center, center for the arts, and lecture center. College libraries are increasingly seen as the center of college campus life, and as such provide the perfect location to host displays and events that foster interdisciplinary collaborations. Augustana College's Thomas Tredway library has served as the “living room of the campus” since it was built in 1992. Tredway Library hosts one major exhibit and corresponding event …

The within-plant distribution of soybean aphid, Aphis glycines Matsumura has been attributed to various causes, yet it is unclear which factor or combination of factors most influence aphid within-plant distribution. Understanding soybean aphid distribution within the soybean canopy is important both in developing sampling programs and in evaluating injury. Because natural enemies have the potential to alter aphid dispersion, we examined how within-plant distribution of soybean aphid was influenced by different natural enemies. Field cages of different mesh diameters were used to exclude different sizes of natural enemies from aphid infested plots. Plots were surveyed and both natural enemy density and soybean aphid density, by strata, were recorded twice weekly. Cages were found to have minimal effect on temperature and soybean plant development. Aphid densities were significantly different each year among dates, treatments, and strata. In 2004 aphid densities were concentrated on the top part of the plant and in 2005 aphid densities were concentrated in the middle of the canopy. Treatments had significant impacts on aphid density in both years of the study. The total exclusion treatment had the highest aphid densities in both years. Treatment also had a significant effect on which stratum aphids were most commonly found. The factor that was found to best explain the differences in aphid distribution was the abundance of natural enemies, primarily Orius insidosus (Say). In treatments left exposed to natural enemies the percentage of the total aphid population was found lower in the canopy. It is clear that aphid densities and distributions are being affected by the presence of natural enemies. Understanding how natural enemies affect the distribution of this economically damaging aphid species is an important component of its management, specifically the development of

We tested procedures for removing adipocere from insect samples to allow identification. An acceptable procedure was determined: (i) Samples were sorted in petri dishes with 75% alcohol to remove any larvae, adult insects, or other soft-bodied material. (ii) Samples of up to 24 puparia were placed in a vial with 15 mL of 95% acetone, capped, and vortexed for a total of 30–90 sec in 10- to 15-sec bursts. This step removed large masses of adipocere or soil from specimen. (iii) Specimens were removed from acetone and placed in a vial of 15 mL of 2% potassium hydroxide (KOH) and vortexed in 10- to 15-sec bursts until all puparia appeared clean (with our samples this required a total of 60–120 sec). (iv) Specimens were removed from the 2% KOH, placed in 75% ethanol, and examined microscopically. (v) Material was stored in 75% ethanol for identification and long-term preservation.

Field experiments were conducted to examine the effects of organic and synthetic soil fertility amendments on soil microbial communities and soil physical and chemical properties at three organic and three conventional vegetable farms in Virginia and Maryland in 1996 and 1997. Two treatments, including either an alternative organic soil amendment (composted cotton-gin trash, composted yard waste, or cattle manure) or synthetic soil amendment (fertilizer) were applied to three replicated plots at each grower field location. Production history and time affected propagule densities of Trichoderma species which remained higher in soils from organic farms. Propagule densities of Trichoderma species, thermophilic microorganisms, and enteric bacteria were also detected in greater numbers in soils amended with alternative than synthetic amendments, whereas propagule densities of Phytophthora and Pythium species were lower in soils amended with alternative than synthetic fertility amendments. Concentrations of Ca, K, Mg, and Mn were higher in soils amended with alternative than synthetic fertility amendments. Canonical correlations and principle component analyses indicated significant correlation between these soil chemical factors and the biological communities. First-order canonical correlations were more negative in fields with a conventional history, and use of synthetic fertilizers, whereas canonical correlations were more positive in fields with a history of organic production and alternative soil amendments. In the first year, yields of corn or melon were not different in soil amended with either synthetic or organic amendments at four of six farms. In the second year, when all growers planted tomatoes, yields were higher on farms with a history of organic production, regardless of soil amendment type. Alternative fertility amendments, enhanced beneficial soil microorganisms reduced pathogen populations, increased soil organic matter, total carbon, and cation exchange capacity (CEC), and lowered bulk density thus improving soil quality.

In preparation for the tenfold luminosity upgrade of the Large Hadron Collider (the HL-LHC) around 2020, three-dimensional (3D) silicon pixel sensors are being developed as a radiation-hard candidate to replace the planar ones currently being used in the CMS pixel detector. This study examines an early batch of FBK sensors (named ATLAS08) of three 3D pixel geometries: 1E, 2E, and 4E, which respectively contain one, two, and four readout electrodes for each pixel, passing completely through the bulk. We present electrical characteristics and beam test performance results for each detector before and after irradiation. The maximum fluence applied is 3.5×1015 n eq /cm2.

Organic wastes may substitute for commercial fertilizers and enhance soil chemical and biological properties. This study compared the effects of commercial fertilizer and organic wastes on soil properties and crop yields on three organic and three conventional vegetable farms in Virginia and Maryland. The organic farms produced sweet corn and the conventional farms produced muskmelon or watermelon in 1996. Commercial N, P and K fertilizers were applied according to Virginia Cooperative Extension (VCE) recommendations. The organic fertility sources, composted cotton gin trash (3 farms), composted yardwaste and livestock manure (2 farms), or beef manure (1 farm), were applied to meet the N needs of each crop according to estimated N mineralization rates of the waste after subtracting estimated cover crop N contributions. The concentrations of most nutrients and soil pH, organic matter, and total C were higher after amending with organic wastes than fertilizer. Populations of Trichoderma and thermophilic microorganisms, known antagonists of pathogenic soilborne fungi, were initially greater in the organically-managed soils, and Trichoderma was higher in organic waste-amended than commercially-fertilized soils at harvest. The beneficial species Trichoderma and Pseudomonas were higher and plant pathogenic oomycete fungi were lower in the organic waste-amended than the commercially-fertilized soils regardless of cultural history. The plant pathogenic fungi increased with time and were greater in plots treated with inorganic fertilizers than organic amendments at harvest. Beneficial soil microorganisms appear to be favored by long term organic amendments, but some groups can be increased with organic amendments within a single season. Yields were similar between treatments, which demonstrates that organic amendments can provide adequate amounts of required plant nutrients in addition to enhancing soil chemical and biological attributes.

We have derived a secondary structure model for 16S ribosomal RNA on the basis of comparative sequence analysis, chemical modification studies and nuclease susceptibility data. Nucleotide sequences of the E. coli and B. brevis 16S rRNA chains, and of RNAse T1 oligomer catalogs from 16S rRNAs of over 100 species of eubacteria were used for phylogenetic comparison. Chemical modification of G by glyoxal, A by m-chloroperbenzoic acid and C by bisulfite in naked 16S rRNA, and G by kethoxal in active and inactive 30S ribosomal subunits was taken as an indication of single stranded structure. Further support for the structure was obtained from susceptibility to RNases A and T1. These three approaches are in excellent agreement. The structure contains fifty helical elements organized into four major domains, in which 46 percent of the nucleotides of 16S rRNA are involved in base pairing. Phylogenetic comparison shows that highly conserved sequences are found principally in unpaired regions of the molecule. No knots are created by the structure.