Dilaton as a Dark Matter Candidate and its Detection

Assuming that the dilaton is the dark matter of the universe, we propose an experiment to detect the relic dilaton using the electromagnetic resonant cavity, based on the dilaton-photon conversion in strong electromagnetic background. We calculate the density of the relic dilaton, and estimate the dilaton mass for which the dilaton becomes the dark matter of the universe. With this we calculate the dilaton detection power in the resonant cavity, and compare it with the axion detection power in similar resonant cavity experiment.Comment: 23 pages, 2 figure

Adolescent Perceptions of Injury and Pressures of Returning to Sport: A Retrospective Qualitative Analysis

The increase in sport participation among adolescents has led to the rise in sport-related injuries, many of which have unique characteristics based on the patient, their perceptions, and the pressures faced when returning to sport. The purpose of this study was to identify the underlying factors that contributed to adolescents’ perceptions of injury and the various pressures they experienced when returning to sport. Two themes emerged from the study: support and fear. Support was provided to participants through development, care, and the environment. Fear was the factor that affected the participant in their return to sport, which came in the form of worry and doubt

Isotopic evidence for dominant secondary production of HONO in near-ground wildfire plumes

Nitrous acid (HONO) is an important precursor to hydroxyl radical (OH) that determines atmospheric oxidative capacity and thus impacts climate and air quality. Wildfire is not only a major direct source of HONO, it also results in highly polluted conditions that favor the heterogeneous formation of HONO from nitrogen oxides (NOx= NO + NO2) and nitrate on both ground and particle surfaces. However, these processes remain poorly constrained. To quantitatively constrain the HONO budget under various fire and/or smoke conditions, we combine a unique dataset of field concentrations and isotopic ratios (15N / 14N and 18O / 16O) of NOx and HONO with an isotopic box model. Here we report the first isotopic evidence of secondary HONO production in near-ground wildfire plumes (over a sample integration time of hours) and the subsequent quantification of the relative importance of each pathway to total HONO production. Most importantly, our results reveal that nitrate photolysis plays a minor role (\u3c5 %) in HONO formation in daytime aged smoke, while NO2-to-HONO heterogeneous conversion contributes 85 %–95 % to total HONO production, followed by OH + NO (5 %–15 %). At nighttime, heterogeneous reduction of NO2 catalyzed by redox active species (e.g., iron oxide and/or quinone) is essential (≥ 75 %) for HONO production in addition to surface NO2 hydrolysis. Additionally, the 18O / 16O of HONO is used for the first time to constrain the NO-to-NO2 oxidation branching ratio between ozone and peroxy radicals. Our approach provides a new and critical way to mechanistically constrain atmospheric chemistry and/or air quality models on a diurnal timescale

On the future of astrostatistics: statistical foundations and statistical practice

This paper summarizes a presentation for a panel discussion on "The Future of Astrostatistics" held at the Statistical Challenges in Modern Astronomy V conference at Pennsylvania State University in June 2011. I argue that the emerging needs of astrostatistics may both motivate and benefit from fundamental developments in statistics. I highlight some recent work within statistics on fundamental topics relevant to astrostatistical practice, including the Bayesian/frequentist debate (and ideas for a synthesis), multilevel models, and multiple testing. As an important direction for future work in statistics, I emphasize that astronomers need a statistical framework that explicitly supports unfolding chains of discovery, with acquisition, cataloging, and modeling of data not seen as isolated tasks, but rather as parts of an ongoing, integrated sequence of analyses, with information and uncertainty propagating forward and backward through the chain. A prototypical example is surveying of astronomical populations, where source detection, demographic modeling, and the design of survey instruments and strategies all interact.Comment: 8 pp, 2 figures. To appear in "Statistical Challenges in Modern Astronomy V," (Lecture Notes in Statistics, Vol. 209), ed. Eric D. Feigelson and G. Jogesh Babu; publication planned for Sep 2012; see http://www.springer.com/statistics/book/978-1-4614-3519-

Assessing the perceived value of Reflexive Groups for supporting Clergy in the Church of England

This is an Accepted Manuscript of an article published by Taylor & Francis in Mental Health, Religion and Culture on 18-7-16, available online: http://dx.doi.org/10.1080/13674676.2016.1197194Little research has been conducted to assess the effectiveness of reflexive groups in supporting clergy. For this research, eight Church of England Bishops’ Advisors for Pastoral Care and Counselling were interviewed to ascertain the value of reflexive groups. These data were analysed using a thematic analysis. Two superordinate themes emerged: Contextual issues and Benefits, along with 20 subordinate themes. An online survey, consisting of questions that came from the Bishops’ Advisors data, was then sent to reflexive group participants (n=64), to see if their experiences matched those benefits identified by the Bishops’ Advisors. The data from 37 participants was statistically analysed. The data from both sets of participants reveal that reflexive groups are psychologically beneficial to clergy. The research concludes that the implementation of reflexive groups as a way of developing self-awareness and enculturating attitudes towards resilience and self-care is important to foster psychologically and spiritually healthy practice

Insights into the 1968–1997 Dasht-e-Bayaz and Zirkuh earthquake sequences, eastern Iran, from calibrated relocations, InSAR and high-resolution satellite imagery

The sequence of seismicity in the Dasht-e-Bayaz and Zirkuh region of northeastern Iran, which includes 11 destructive earthquakes within a period of only 30 years, forms one of the most outstanding examples of clustered large and intermediate-magnitude seismic activity in the world.We perform a multiple-event relocation analysis, with procedures to remove systematic location bias, of 169 earthquakes, most of which occurred in the period 1968–2008, to better image the distribution of seismicity within this highly active part of Iran. The geographic locations of the clustered earthquakes were calibrated by the inclusion of phase arrivals from seismic stations at short epicentral distances, and also by matching the relative locations of the three largest events in the study to their mapped surface ruptures. The two independent calibration methods provide similar results that increase our confidence in the accuracy of the distribution of relocated epicentres. These calibrated epicentres, combined with the mapping of faults from high-resolution satellite imagery, and from an InSAR-derived constraint on fault location in one case, allow us to associate individual events with specific faults, and even with specific segments of faults, to better understand the nature of the active tectonics in this region during the past four decades. Several previous assumptions about the seismicity in this region are confirmed: (1) that the 1968 August 30 Mw 7.1 Dasht-e-Bayaz earthquake nucleated at a prominent segment boundary and left-step in the fault trace, (2) that the 1968 September 11 Mw 5.6 aftershock occurred on the Dasht-e-Bayaz fault at the eastern end of the 1968 rupture and (3) that the 1976 November 7 Mw 6.0 Qayen earthquake probably occurred on the E–W left-lateral Avash Fault. We show, in addition, that several significant events, including the 1968 September 1 and 4 (Mw 6.3 and 5.5) Ferdows earthquakes, the 1979 January 16 (Mw 6.5) and 1997 June 25 (Mw 5.9) Boznabad events and the 1979 December 7 (Mw 5.9) Kalat-e-Shur earthquake are likely to have ruptured previously unknown faults. Our improved description of the faulting involved in the 1968–1997 earthquake sequence highlights the importance of rupturing of conjugate left- and right-lateral faults in closely spaced events, or potentially even within a single earthquake, as was likely the case at the eastern end of the 1979 November 27 (Mw 7.1) Khuli-Buniabad main shock. The high level of clustered seismic activity probably results from the simultaneous activity on left- and right-lateral faults, an inherently unstable arrangement that must evolve rapidly. The combination of high-resolution satellite imagery and calibrated earthquake locations is a useful tool for investigating active tectonics, even in the absence of detailed field observations

Does backreaction enforce the averaged null energy condition in semiclassical gravity?

The expected stress-energy tensor of quantum fields generically violates the local positive energy conditions of general relativity. However, may satisfy some nonlocal conditions such as the averaged null energy condition (ANEC), which would rule out traversable wormholes. Although ANEC holds in Minkowski spacetime, it can be violated in curved spacetimes if one is allowed to choose the spacetime and quantum state arbitrarily, without imposition of the semiclassical Einstein equation G_{ab} = 8 \pi . In this paper we investigate whether ANEC holds for solutions to this equation, by studying a free, massless scalar field with arbitrary curvature coupling in perturbation theory to second order about the flat spacetime/vacuum solution. We "reduce the order" of the perturbation equations to eliminate spurious solutions, and consider the limit in which the lengthscales determined by the incoming state are much larger than the Planck length. We also need to assume that incoming classical gravitational radiation does not dominate the first order metric perturbation. We find that although the ANEC integral can be negative, if we average the ANEC integral transverse to the geodesic with a suitable Planck scale smearing function, then a strictly positive result is obtained in all cases except for the flat spacetime/vacuum solution. This result suggests --- in agreement with conclusions drawn by Ford and Roman from entirely independent arguments --- that if traversable wormholes do exist as solutions to the semiclassical equations, they cannot be macroscopic but must be ``Planck scale''. A large portion of our paper is devoted to the analysis of general issues concerning the nature of the semiclassical Einstein equation and of prescriptions for extracting physically relevant solutions.Comment: 54 pages, 3 figures, uses revtex macros and epsf.tex, to appear in Phys Rev D. A new appendix has been added showing consistency of our results with recent results of Visser [gr-qc/9604008]. Some corrections were made to Appendix A, and several other minor changes to the body of the paper also were mad

"An infinitude of Possible Worlds": towards a research method for hypertext fiction

While the investigation of creative writing as a research method is gathering apace, little work has been done into the specific case of hypertext fiction (fiction written through a digital medium). This paper argues that, while there remain certain similarities between paper-based and digital texts, fundamental differences in design and construction remain. If hypertext fictions are to be successfully understood, then the role and purpose of the digital writer needs to be more fully analysed as part of the creative process. This paper argues that Possible Worlds Theory offers a way forward. With its focus on the ontological structures created by hypertext fiction, Possible World Theory actively embraces narrative indeterminacy and ontological changeability. In this sense the method provides a structured means by which the creative manipulation of the unique affordances of a digital medium by a writer can be theorised

Clathrin Is Spindle-Associated but Not Essential for Mitosis

Clathrin is a multimeric protein involved in vesicle coat assembly. Recently clathrin distribution was reported to change during the cell cycle and was found to associate with the mitotic spindle. Here we test whether the recruitment of clathrin to the spindle is indicative of a critical functional contribution to mitosis.Previously a chicken pre-B lymphoma cell line (DKO-R) was developed in which the endogenous clathrin heavy chain alleles were replaced with the human clathrin heavy chain under the control of a tetracycline-regulatable promoter. Receptor-mediated and fluid-phase endocytosis were significantly inhibited in this line following clathrin knockout, and we used this to explore the significance of clathrin heavy chain expression for cell cycle progression. We confirmed using confocal microscopy that clathrin colocalised with tubulin at mitotic spindles. Using a propidium iodide flow cytometric assay we found no statistical difference in the cell cycle distribution of the knockout cells versus the wild-type. Additionally, we showed that the ploidy and the recovery kinetics following cell cycle arrest with nocodazole were unchanged by repressing clathrin heavy chain expression.We conclude that the association of clathrin with the mitotic spindle and the contribution of clathrin to endocytosis are evolutionarily conserved. However we find that the contribution of clathrin to mitosis is less robust and dependent on cellular context. In other cell-lines silencing RNA has been used by others to knockdown clathrin expression resulting in an increase in the mitotic index of the cells. We show an effect on the G2/M phase population of clathrin knockdown in HEK293 cells but show that repressing clathrin expression in the DKO-R cell-line has no effect on the size of this population. Consequently this work highlights the need for a more detailed molecular understanding of the recruitment and function of clathrin at the spindle, since the localisation but not the impact of clathrin on mitosis appears to be robust in plants, mammalian and chicken B-cells

Spontaneous emission in a planar Fabry-Perot microcavity

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