226 research outputs found

    Counselors as Advocates: Effects of a Pilot Project Designed to Develop Advocacy Knowledge and Confidence in Trainees

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    While there has been increased attention to advocacy within counseling and counseling psychology, it has been noted that trainees generally feel unprepared to engage in advocacy and do not participant e in this type of work to a large extent, even with increased age or professional experience). The qualitative study summarizes the findings of a project within a graduate multicultural counseling course designed to increase trainee knowledge and confidence related to advocacy. This project required students (N = 19) to complete individual advocacy projects in the community, with opportunities for self-reflection and evaluation of their progress throughout the semester. Student reflection responses about the effects of this project were analyzed using methods from Grounded Theory by a collaborative research team. This process resulted in a core category of responses that included expanded definitions of advocacy, increased self-confidence regarding advocacy work, obstacles encountered, and reactions to the course assignment. Implications and future directions are discussed

    On the road to diploidization? Homoeolog loss in independently formed populations of the allopolyploid Tragopogon miscellus (Asteraceae)

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    <p>Abstract</p> <p>Background</p> <p>Polyploidy (whole-genome duplication) is an important speciation mechanism, particularly in plants. Gene loss, silencing, and the formation of novel gene complexes are some of the consequences that the new polyploid genome may experience. Despite the recurrent nature of polyploidy, little is known about the genomic outcome of independent polyploidization events. Here, we analyze the fate of genes duplicated by polyploidy (homoeologs) in multiple individuals from ten natural populations of <it>Tragopogon miscellus </it>(Asteraceae), all of which formed independently from <it>T. dubius </it>and <it>T. pratensis </it>less than 80 years ago.</p> <p>Results</p> <p>Of the 13 loci analyzed in 84 <it>T. miscellus </it>individuals, 11 showed loss of at least one parental homoeolog in the young allopolyploids. Two loci were retained in duplicate for all polyploid individuals included in this study. Nearly half (48%) of the individuals examined lost a homoeolog of at least one locus, with several individuals showing loss at more than one locus. Patterns of loss were stochastic among individuals from the independently formed populations, except that the <it>T. dubius </it>copy was lost twice as often as <it>T. pratensis</it>.</p> <p>Conclusion</p> <p>This study represents the most extensive survey of the fate of genes duplicated by allopolyploidy in individuals from natural populations. Our results indicate that the road to genome downsizing and ultimate genetic diploidization may occur quickly through homoeolog loss, but with some genes consistently maintained as duplicates. Other genes consistently show evidence of homoeolog loss, suggesting repetitive aspects to polyploid genome evolution.</p

    Similar patterns of rDNA evolution in synthetic and recently formed natural populations of Tragopogon (Asteraceae) allotetraploids

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    <p>Abstract</p> <p>Background</p> <p><it>Tragopogon mirus </it>and <it>T. miscellus </it>are allotetraploids (2<it>n </it>= 24) that formed repeatedly during the past 80 years in eastern Washington and adjacent Idaho (USA) following the introduction of the diploids <it>T. dubius</it>, <it>T. porrifolius</it>, and <it>T. pratensis </it>(2<it>n </it>= 12) from Europe. In most natural populations of <it>T. mirus </it>and <it>T. miscellus</it>, there are far fewer 35S rRNA genes (rDNA) of <it>T. dubius </it>than there are of the other diploid parent (<it>T. porrifolius </it>or <it>T. pratensis</it>). We studied the inheritance of parental rDNA loci in allotetraploids resynthesized from diploid accessions. We investigate the dynamics and directionality of these rDNA losses, as well as the contribution of gene copy number variation in the parental diploids to rDNA variation in the derived tetraploids.</p> <p>Results</p> <p>Using Southern blot hybridization and fluorescent <it>in situ </it>hybridization (FISH), we analyzed copy numbers and distribution of these highly reiterated genes in seven lines of synthetic <it>T. mirus </it>(110 individuals) and four lines of synthetic <it>T. miscellus </it>(71 individuals). Variation among diploid parents accounted for most of the observed gene imbalances detected in F<sub>1 </sub>hybrids but cannot explain frequent deviations from repeat additivity seen in the allotetraploid lines. Polyploid lineages involving the same diploid parents differed in rDNA genotype, indicating that conditions immediately following genome doubling are crucial for rDNA changes. About 19% of the resynthesized allotetraploid individuals had equal rDNA contributions from the diploid parents, 74% were skewed towards either <it>T. porrifolius </it>or <it>T. pratensis</it>-type units, and only 7% had more rDNA copies of <it>T. dubius</it>-origin compared to the other two parents. Similar genotype frequencies were observed among natural populations. Despite directional reduction of units, the additivity of 35S rDNA locus number is maintained in 82% of the synthetic lines and in all natural allotetraploids.</p> <p>Conclusions</p> <p>Uniparental reductions of homeologous rRNA gene copies occurred in both synthetic and natural populations of <it>Tragopogon </it>allopolyploids. The extent of these rDNA changes was generally higher in natural populations than in the synthetic lines. We hypothesize that locus-specific and chromosomal changes in early generations of allopolyploids may influence patterns of rDNA evolution in later generations.</p

    The impact of adolescent exposure to medical marijuana laws on high school completion, college enrollment and college degree completion

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    Background: There is concern that medical marijuana laws (MMLs) could negatively affect adolescents. To better understand these policies, we assess how adolescent exposure to MMLs is related to educational attainment. Methods: Data from the 2000 Census and 2001-2014 American Community Surveys were restricted to individuals who were of high school age (14-18) between 1990 and 2012 (n = 5,483,715). MML exposure was coded as: (i) a dichotomous any MML indicator, and (ii) number of years of high school age exposure. We used logistic regression to model whether MMLs affected: (a) completing high school by age 19; (b) beginning college, irrespective of completion; and (c) obtaining any degree after beginning college. A similar dataset based on the Youth Risk Behavior Survey (YRBS) was also constructed for confirmatory analyses assessing marijuana use. Results: MMLs were associated with a 0.40 percentage point increase in the probability of not earning a high school diploma or GED after completing the 12th grade (from 3.99% to 4.39%). High school MML exposure was also associated with a 1.84 and 0.85 percentage point increase in the probability of college non-enrollment and degree non-completion, respectively (from 31.12% to 32.96% and 45.30% to 46.15%, respectively). Years of MML exposure exhibited a consistent dose response relationship for all outcomes. MMLs were also associated with 0.85 percentage point increase in daily marijuana use among 12th graders (up from 1.26%). Conclusions: Medical marijuana law exposure between age 14 to 18 likely has a delayed effect on use and education that persists over time. (C) 2016 Elsevier Ireland Ltd. All rights reserved

    Transient absorption and reshaping of ultrafast XUV light by laser-dressed helium

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    We present a theoretical study of transient absorption and reshaping of extreme ultraviolet (XUV) pulses by helium atoms dressed with a moderately strong infrared (IR) laser field. We formulate the atomic response using both the frequency-dependent absorption cross section and a time-frequency approach based on the time-dependent dipole induced by the light fields. The latter approach can be used in cases when an ultrafast dressing pulse induces transient effects, and/or when the atom exchanges energy with multiple frequency components of the XUV field. We first characterize the dressed atom response by calculating the frequency-dependent absorption cross section for XUV energies between 20 and 24 eV for several dressing wavelengths between 400 and 2000 nm and intensities up to 10^12 W/cm^2. We find that for dressing wavelengths near 1600 nm, there is an Autler-Townes splitting of the 1s ---> 2p transition that can potentially lead to transparency for absorption of XUV light tuned to this transition. We study the effect of this XUV transparency in a macroscopic helium gas by incorporating the time-frequency approach into a solution of the coupled Maxwell-Schr\"odinger equations. We find rich temporal reshaping dynamics when a 61 fs XUV pulse resonant with the 1s ---> 2p transition propagates through a helium gas dressed by an 11 fs, 1600 nm laser pulse.Comment: 13 pages, 8 figures, 1 table, RevTeX4, revise

    Seasonal Performance of White Clover in Mixed-Sward Grazing Pasture Highlights Genotype by Environment Interaction

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    White clover is an important forage crop because of its nutritional value, ability to provide plantavailable nitrogen via symbiosis with Rhizobium soil bacteria, and year-round availability of dry matter (DM) yield. However, its performance in mixed sward-based pastures is characterised by seasonal variability and declining DM yield over time. The identification of white clover genotypes adapted for across seasonal performance is an important goal in white clover breeding. In this study, we evaluated the seasonal performance of 200 white clover half-sib families using visual growth scores and calibrated dry matter yield based on growth scores measured for three years in two locations. Results showed significant variation for growth scores across years, seasons and locations. Significant G×E was observed in the form of year, location and season interactions. Calibrated DM yield was highest in the second-year summer with clover content declining in the third year. Spring and winter were identified as potential vulnerable periods for white clover growth in pastures

    Transcriptomic Shock Generates Evolutionary Novelty in a Newly Formed, Natural Allopolyploid Plant

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    SummaryNew hybrid species might be expected to show patterns of gene expression intermediate to those shown by parental species [1, 2]. “Transcriptomic shock” may also occur, in which gene expression is disrupted; this may be further modified by whole genome duplication (causing allopolyploidy) [3–16]. “Shock” can include instantaneous partitioning of gene expression between parental copies of genes among tissues [16–19]. These effects have not previously been studied at a population level in a natural allopolyploid plant species. Here, we survey tissue-specific expression of 144 duplicated gene pairs derived from different parental species (homeologs) in two natural populations of 40-generation-old allotetraploid Tragopogon miscellus (Asteraceae) plants. We compare these results with patterns of allelic expression in both in vitro “hybrids” and hand-crossed F1 hybrids between the parental diploids T. dubius and T. pratensis, and with patterns of homeolog expression in synthetic (S1) allotetraploids. Partitioning of expression was frequent in natural allopolyploids, but F1 hybrids and S1 allopolyploids showed less partitioning of expression than the natural allopolyploids and the in vitro “hybrids” of diploid parents. Our results suggest that regulation of gene expression is relaxed in a concerted manner upon hybridization, and new patterns of partitioned expression subsequently emerge over the generations following allopolyploidization
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