690 research outputs found

    Differential Effects of Internal and External Constraints on Sustainability Intentions: A Hierarchical Regression Analysis of Running Event Participants by Market Segment

    Get PDF
    There are immediate calls to action across all business sectors to address the adverse effects of climate change. The sport industry is not immune to these calls—practitioners have engaged participants to further the environmental initiatives of their events through creative messaging campaigns with mixed success. We examine the differential effects of internal and external constraints on sustainability intentions by market segment of a running event’s participants. This furthers our understanding of how to engage sport participants in sustainable behaviors at a sport event and improves the sustainable behavior outcomes of messaging campaigns. Our results support the principles of constraint theory and that internal constraints need to be addressed before external constraints are relevant. Internal constraints, such as lack of knowledge and lack of worth, predict variance in intentions to act sustainably (i.e., to dispose of waste correctly). After controlling for internal constraints, the external constraints of lack of interest by others to act sustainably, and lack of access and time, explain additional variance in sustainability intentions. We also found that each market segment varies on the impact of constraints that inhibit sustainability intentions, with the amount of variance in sustainability intention explained by such constraints varying from as low as 11.4% in one segment to as high as 33.1% in another. We then provide specific recommendations for future research and discuss how practitioners can use these results to ameliorate these constraints and increase sustainability intentions

    Differential Effects of Internal and External Constraints on Sustainability Intentions: A Hierarchical Regression Analysis of Running Event Participants by Market Segment

    Get PDF
    There are immediate calls to action across all business sectors to address the adverse effects of climate change. The sport industry is not immune to these calls—practitioners have engaged participants to further the environmental initiatives of their events through creative messaging campaigns with mixed success. We examine the differential effects of internal and external constraints on sustainability intentions by market  segment of a running event’s participants. This furthers our understanding of how to engage sport participants in sustainable behaviors at a sport event and improves the sustainable behavior outcomes of messaging campaigns. Our results support the principles of constraint theory and that internal constraints need to be addressed before external constraints are relevant. Internal constraints, such as lack of knowledge and lack of worth, predict variance in intentions to act sustainably (i.e., to dispose of waste correctly). After controlling for internal constraints, the external constraints of lack of interest by others to act sustainably, and lack of access and time, explain additional variance in sustainability intentions. We also found that each market segment varies on the impact of constraints that inhibit sustainability intentions, with the amount of variance in sustainability intention explained by such constraints varying from as low as 11.4% in one segment to as high as 33.1% in another. We then provide specific recommendations for future research and discuss how practitioners can use these results to ameliorate these constraints and increase sustainability intentions

    Optimized primers and other critical conditions for efficient fusion PCR to generate knockout vectors in filamentous fungi.

    Get PDF
    Methods to streamline functional studies of large numbers of genes are essential to fully utilize the significant genomic resources now available for fungi. Fusion PCR is often used to join pieces of DNA together, particularly in the construction of DNA fragments for gene replacement in fungi. Here we present high-efficiency primers which reliably direct fusion and amplification to generate constructs for gene knockouts. Addendum: The authors communicated this omission post publication: We inadvertently left out the 3HS sequence with which we had such great success. The 5HS sequence, as seen in Figure 2D, is 5\u27-AGTCGACGACAACTACCATCGATCTGACG. The 3HS sequence which was missing from the original paper is 5\u27-ACACTGGTGACGGCTAACCAGAACTGTCA

    Quantum Monte Carlo study of the Ne atom and the Ne+ ion

    Full text link
    We report all-electron and pseudopotential calculations of the ground-stateenergies of the neutral Ne atom and the Ne+ ion using the variational and diffusion quantum Monte Carlo (DMC) methods. We investigate different levels of Slater-Jastrow trial wave function: (i) using Hartree-Fock orbitals, (ii) using orbitals optimized within a Monte Carlo procedure in the presence of a Jastrow factor, and (iii) including backflow correlations in the wave function. Small reductions in the total energy are obtained by optimizing the orbitals, while more significant reductions are obtained by incorporating backflow correlations. We study the finite-time-step and fixed-node biases in the DMC energy and show that there is a strong tendency for these errors to cancel when the first ionization potential (IP) is calculated. DMC gives highly accurate values for the IP of Ne at all the levels of trial wave function that we have considered

    Accurate structure factors from pseudopotential methods

    Full text link
    Highly accurate experimental structure factors of silicon are available in the literature, and these provide the ideal test for any \emph{ab initio} method for the construction of the all-electron charge density. In a recent paper [J. R. Trail and D. M. Bird, Phys. Rev. B {\bf 60}, 7863 (1999)] a method has been developed for obtaining an accurate all-electron charge density from a first principles pseudopotential calculation by reconstructing the core region of an atom of choice. Here this method is applied to bulk silicon, and structure factors are derived and compared with experimental and Full-potential Linear Augmented Plane Wave results (FLAPW). We also compare with the result of assuming the core region is spherically symmetric, and with the result of constructing a charge density from the pseudo-valence density + frozen core electrons. Neither of these approximations provide accurate charge densities. The aspherical reconstruction is found to be as accurate as FLAPW results, and reproduces the residual error between the FLAPW and experimental results.Comment: 6 Pages, 3 figure

    The Fast-Evolving phy-2 Gene Modulates Sexual Development in Response to Light in the Model Fungus Neurospora crassa

    Get PDF
    Rapid responses to changes in incident light are critical to the guidance of behavior and development in most species. Phytochrome light receptors in particular play key roles in bacterial physiology and plant development, but their functions and regulation are less well understood in fungi. Nevertheless, genome-wide expression measurements provide key information that can guide experiments that reveal how genes respond to environmental signals and clarify their role in development. We performed functional genomic and phenotypic analyses of the two phytochromes in Neurospora crassa, a fungal model adapted to a postfire environment that experiences dramatically variable light conditions. Expression of phy-1 and phy-2 was low in early sexual development and in the case of phy-2 increased in late sexual development. Under light stimulation, strains with the phytochromes deleted exhibited increased expression of sexual development-related genes. Moreover, under red light, the phy-2 knockout strain commenced sexual development early. In the evolution of phytochromes within ascomycetes, at least two duplications have occurred, and the faster-evolving phy-2 gene has frequently been lost. Additionally, the three key cysteine sites that are critical for bacterial and plant phytochrome function are not conserved within fungal phy-2 homologs. Through the action of phytochromes, transitions between asexual and sexual reproduction are modulated by light level and light quality, presumably as an adaptation for fast asexual growth and initiation of sexual reproduction of N. crassa in exposed postfire ecosystems

    Li zoning in zircon as a potential geospeedometer and peak temperature indicator

    Get PDF
    Zircon Li concentrations and δ[superscript 7]Li values may potentially trace crustal recycling because continental and mantle-derived zircons yield distinct values. The usefulness of these differences may depend upon the retentivity of zircon to Li concentrations and isotopic ratios. Given the relatively high Li diffusivities measured by Cherniak and Watson (Contrib Mineral Petrol 160: 383–390, 2010), we sought to discover the scenarios under which Li mobility might be inhibited by charge-compensating cations. Toward this end, we conducted “in” diffusion experiments in which Li depth profiles of synthetic Lu-doped, P-doped, and undoped zircon were determined by nuclear reaction analysis. In separate experiments, Li was ion-implanted at depth within polished natural zircon slabs to form a Gaussian Li concentration profile. Diffusively relaxed concentration profiles were measured after heating the slabs to determine diffusivities. In all experiments, which ranged from 920 to 650 °C, calculated diffusivities are in agreement with a previously established Arrhenius relationship calibrated on trace-element-poor Mud Tank zircon. Our revised Arrhenius relationship that includes both datasets is: D[subscript Li] = 9.60 x 10[superscript -7] exp [-278 ± 8 kJ mol[superscript - 1]/RT] m[superscript 2] s[superscript - 1] We also observed that synthetic sector-zoned zircon exhibits near-step-function Li concentration profiles across sectors that correlate with changes in the rare earth element (REE) and P concentrations. This allowed us to examine how Li diffusion might couple with REE diffusion in a manner different than that described above. In particular, re-heating these grains revealed significant Li migration, but no detectable migration of the rare earth elements. Thus, unlike most elements in zircon which are not mobile at the micrometer scale under most time–temperature paths in the crust, Li zoning, relaxation of zoning, or lack of zoning altogether could be used to reveal time–temperature information. Discrete ~10 μm concentration zones of Li within zircon may be partially preserved at 700 °C for tens to hundreds of years, and at 450 °C for millions of years. In this regard, Li zoning in zircon holds significant potential as a geospeedometer, and in some instances as a qualitative indicator of the maximum temperature experienced by the zircon

    Downscaling a Global Climate Model to Simulate Climate Change Impacts on U.S. Regional and Urban Air Quality

    Get PDF
    Climate change can exacerbate future regional air pollution events by making conditions more favorable to form high levels of ozone. In this study, we use spectral nudging with WRF to downscale NASA earth system GISS modelE2 results during the years 2006 to 2010 and 2048 to 2052 over the continental United States in order to compare the resulting meteorological fields from the air quality perspective during the four seasons of five-year historic and future climatological periods. GISS results are used as initial and boundary conditions by the WRF RCM to produce hourly meteorological fields. The downscaling technique and choice of physics parameterizations used are evaluated by comparing them with in situ observations. This study investigates changes of similar regional climate conditions down to a 12km by 12km resolution, as well as the effect of evolving climate conditions on the air quality at major U.S. cities. The high resolution simulations produce somewhat different results than the coarse resolution simulations in some regions. Also, through the analysis of the meteorological variables that most strongly influence air quality, we find consistent changes in regional climate that would enhance ozone levels in four regions of the U.S. during fall (Western U.S., Texas, Northeastern, and Southeastern U.S), one region during summer (Texas), and one region where changes potentially would lead to better air quality during spring (Northeast). We also find that daily peak temperatures tend to increase in most major cities in the U.S. which would increase the risk of health problems associated with heat stress. Future work will address a more comprehensive assessment of emissions and chemistry involved in the formation and removal of air pollutants

    The use of chemoprophylaxis in East African Zebu village cattle exposed to trypanosomiasis in Muhaka, Kenya

    Get PDF
    A study conducted to assess the efficacy of chemoprophylaxis for the improvement of the health and productivity of East African Zebu village cattle exposed to trypanosomiasis. Examines the cost-effectiveness of the treatment. Includes data on calf pre-weaning health and weight traits, weight traits of calves from 12-18 months of age, calf post-weaning health and weight traits, and breeding cow health and production traits - for the non-prophylactic and prophylactic groups
    • …
    corecore