Morphodynamics, sedimentation and sediment dynamics of a gravel beach

The morphodyiiamics of a gravel barrier beadi in Devon, \JK (Slaptou Sands: tau/S 0.15 - 0.25, D50 2 - 8min), was studied with reference to its sedimentology. Three time scales were sampled for nearshore hydrodynamics, intertidal morphologies and sediirientologies. A series of surveys were carried out over individual tidal cycles (samphng every 5 - lOmins for between 6 and 91irs); on •consecutive low tides over half-lunar tidal cycles (1 -2 cross-shore profiles-sampled every 0.5 - Ini, on 2 spring - spring tidal cycles comprising 26 and 24 tides, respectively); and finally eveiy 2 weeks at spring low tide, over 1 calendar year (13-17 profile lines survej'ed and sampled for sediment over 3.25 - 4.251an). In order to further our understanding of gravel beaches, sediment data needs to, be collected at a resolution similar to that of the hydrodynamics. Innovative automatic sediment sizing techniques based on digital images of sediments were therefore developed, and software written, to allow the collection and analysis of high-resolution sediment data. The gi-avel beach step and berm are accretionaiy features, tidally modulated, and evolve under different time scales. A new technique to determine bed mobility from the nearshore, using underwater ^adeo cameras, was devised. Nearsliore sediment transport was suggested as being related to sub-incident wave frequencies. No aspect of morphological change could be found to havea statistically significant association with sedimentological change, but dimensional-reduction techniques did satisfactorily detect association. The lack of co-variance and obvious patterns is stochastic noise, not • parameterisation. Over one year, the barrier underwent asymmetrical rotation over one year, highlighting the importance of alongshore sediment transport processes on this supposedly 'swash aligned' beach. A statistical model based on the log-hj'perbolic distribution of sinface particle sizes was found to be a reasonable predictor of mean net sedimentation over individual tides. Its complicated parameter space could possibly map'onto a simpler plane based on traditional moments. Sediment trend vector models based on sorting alone out-performed a traditional approach. Moments of a surface grain-size'distribution appear to be inappropriate to characterise sedimentological change at time-scales gi-eater than a semi-diurnal tidal cycle. Sub-surface sampling on the intertidal zone on diurnal and semi-lunar time-scales is useful in assessing the dynamics of the step, itself an important mechanism for onshore and offshore net volumetric transport.School of Geograph

Evaluating unsupervised methods to size and classify suspended particles using digital in-line holography

Substantial information can be gained from digital in-line holography of marine particles, eliminating depth-of-field and focusing errors associated with standard lens-based imagingmethods.However, for the technique to reach its full potential in oceanographic research, fully unsupervised (automated) methods are required for focusing, segmentation, sizing, and classification of particles. These computational challenges are the subject of this paper, in which the authors draw upon data collected using a variety of holographic systems developed at Plymouth University, United Kingdom, from a significant range of particle types, sizes, and shapes. A new method for noise reduction in reconstructed planes is found to be successful in aiding particle segmentation and sizing. The performance of an automated routine for deriving particle characteristics (and subsequent size distributions) is evaluated against equivalent size metrics obtained by a trained operative measuring grain axes on screen. The unsupervised method is found to be reliable, despite some errors resulting from oversegmentation of particles. A simple unsupervised particle classification system is developed and is capable of successfully differentiating sand grains, bubbles, and diatoms from within the surfzone. Avoiding miscounting bubbles and biological particles as sand grains enables more accurate estimates of sand concentrations and is especially important in deployments of particle monitoring instrumentation in aerated water. Perhaps the greatest potential for further development in the computational aspects of particle holography is in the area of unsupervised particle classification. The simple method proposed here provides a foundation upon which further development could lead to reliable identification of more complex particle populations, such as those containing phytoplankton, zooplankton, flocculated cohesive sediments, and oil droplets

Racial and Ethnic Differences in Falls Among Older Adults: a Systematic Review and Meta-analysis

The aim of this systematic review and meta-analysis was to determine whether differences in reported fall rates exist between different ethnic groups. Searches were carried out on four databases: Medline, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus, and Web of Science. Only English language studies with community-dwelling participants aged 60 + years were included. Studies also needed to compare fall prevalence for at least two or more ethnic groups. Two reviewers independently screened all articles and evaluated study quality. Twenty-three articles were included for systematic review, and meta-analyses were carried out on the 16 retrospective studies that reported falls in the previous 12 months. The Asian group demonstrated significantly lower fall prevalence than all other ethnic groups at 13.89% (10.87, 16.91). The Hispanic group had a fall prevalence of 18.54% (12.95, 24.13), closely followed by the Black group at 18.60% (13.27, 23.93). The White group had the highest prevalence at 23.77% (18.66, 28.88). Some studies provided adjusted estimates of effect statistics for the odds/risk of falls, which showed that differences still existed between some ethnic groups even after adjusting for other risk factors. Overall, differences in fall prevalence do appear to exist between different ethnic groups, although the reasons for these differences currently remain undetermined and require further investigation. These findings highlight the need to provide more ethnically tailored responses to public health challenges, which could potentially increase the adherence to prevention interventions, and allow for a more targeted use of resources

Spirituality and Basketball Fanship: An Interpretative Phenomenological Analysis and Synthesis

The world of competitive sport affords an individual the opportunity to enter a spiritual community adding meaning that transcends one’s current understanding of life (Parry et al. 2007). Previously established dimensions of sports fanship (group affiliation, psychological commitment and team identification) share characteristics commonly associated with religious or spiritual affiliation indicating that fans may generate substantial life meaning from observing sporting encounters. In the present study, 12 male basketball fans (M=32.42; SD=7.97) completed semi-structured interviews immediately prior to viewing a competitive match at the 2011 European Basketball Championships (Vilnius, Lithuania). Interviews were structured under four headings; 1) the most memorable moment as a basketball fan, 2) thoughts, feelings and emotions attached to their team, 3) affiliation to the team in the context of the fan’s meaning of life, 4) connection with members of the fan’s sporting community. Interpretative Phenomenological Analysis was employed to analyse interview transcripts. Raw data clustered into four dimensions; 1) devotion, 2) obscure emotions, 3) connectedness, and 4) universal values. The results indicate that sports fanship is characterised by, and synonymous with, an established understanding of spirituality derived from membership of wider spiritual and/or religious communities. The findings hold implications for the marketing and membership of local, amateur and professional sports clubs and brands, as well as community development, health and welfare

The Early Palomar Program (1950-1955) for the Discovery of Classical Novae in M81: Analysis of the Spatial Distribution, Magnitude Distribution, and Distance Suggestion

Data obtained in the 1950-1955 Palomar campaign for the discovery of classical novae in M81 are set out in detail. Positions and apparent B magnitudes are listed for the 23 novae that were found. There is modest evidence that the spatial distribution of the novae does not track the B brightness distribution of either the total light or the light beyond an isophotal radius that is 70\arcsec from the center of M81. The nova distribution is more extended than the aforementioned light, with a significant fraction of the sample appearing in the outer disk/spiral arm region. We suggest that many (perhaps a majority) of the M81 novae that are observed at any given epoch (compared with say $10^{10}$ years ago) are daughters of Population I interacting binaries. The conclusion that the present day novae are drawn from two population groups, one from low mass white dwarf secondaries of close binaries identified with the bulge/thick disk population, and the other from massive white dwarf secondaries identified with the outer thin disk/spiral arm population, is discussed. We conclude that the M81 data are consistent with the two population division as argued previously from (1) the observational studies on other grounds by Della Valle et al. (1992, 1994), Della Valle & Livio (1998), and Shafter et al. (1996) of nearby galaxies, (2) the Hatano et al. (1997a,b) Monte Carlo simulations of novae in M31 and in the Galaxy, and (3) the Yungelson et al. (1997) population synthesis modeling of nova binaries. Two different methods of using M81 novae as distance indicators give a nova distance modulus for M81 as $(m-M)_0 = 27.75$, consistent with the Cepheid modulus that is the same value.Comment: 24 pages, 7 figures, accepted to PAS

Studying the Pulsation of Mira Variables in the Ultraviolet

We present results from an empirical study of the Mg II h & k emission lines of selected Mira variable stars, using spectra from the International Ultraviolet Explorer (IUE). The stars all exhibit similar Mg II behavior during the course of their pulsation cycles. The Mg II flux always peaks after optical maximum near pulsation phase 0.2-0.5, although the Mg II flux can vary greatly from one cycle to the next. The lines are highly blueshifted, with the magnitude of the blueshift decreasing with phase. The widths of the Mg II lines are also phase-dependent, decreasing from about 70 km/s to 40 km/s between phase 0.2 and 0.6. We also study other UV emission lines apparent in the IUE spectra, most of them Fe II lines. These lines are much narrower and not nearly as blueshifted as the Mg II lines. They exhibit the same phase-dependent flux behavior as Mg II, but they do not show similar velocity or width variations.Comment: 26 pages, 12 figures; AASTEX v5.0 plus EPSF extensions in mkfig.sty; to appear in Ap

An Analysis of the Shapes of Interstellar Extinction Curves. V. The IR-Through-UV Curve Morphology

We study the IR-through-UV interstellar extinction curves towards 328 Galactic B and late-O stars. We use a new technique which employs stellar atmosphere models in lieu of unreddened "standard" stars. This technique is capable of virtually eliminating spectral mismatch errors in the curves. It also allows a quantitative assessment of the errors and enables a rigorous testing of the significance of relationships between various curve parameters, regardless of whether their uncertainties are correlated. Analysis of the curves gives the following results: (1) In accord with our previous findings, the central position of the 2175 A extinction bump is mildly variable, its width is highly variable, and the two variations are unrelated. (2) Strong correlations are found among some extinction properties within the UV region, and within the IR region. (3) With the exception of a few curves with extreme (i.e., large) values of R(V), the UV and IR portions of Galactic extinction curves are not correlated with each other. (4) The large sightline-to-sightline variation seen in our sample implies that any average Galactic extinction curve will always reflect the biases of its parent sample. (5) The use of an average curve to deredden a spectral energy distribution (SED) will result in significant errors, and a realistic error budget for the dereddened SED must include the observed variance of Galactic curves. While the observed large sightline-to-sightline variations, and the lack of correlation among the various features of the curves, make it difficult to meaningfully characterize average extinction properties, they demonstrate that extinction curves respond sensitively to local conditions. Thus, each curve contains potentially unique information about the grains along its sightline.Comment: To appear in the Astrophysical Journal, Part 1, July 1, 2007. Figures and Tables which will appear only in the electronic version of the Journal can be obtained via anonymous ftp from ftp://ftp.astronomy.villanova.edu . After logging in, change directories to "fitz/FMV_EXTINCTION". A README file describes the various files present in the director

Standardisation of a mental skills scale in South Africa and the United Kingdom

The contemporary science of sport and exercise psychology requires the standardisation of mental skills questionnaires to facilitate accurate assessment of and intervention for individuals and groups in various health and sport related contexts. The study presents international research findings regarding the standardisation of a Mental Skills Scale with a sample of university students (N=420) from South Africa (n=211) and the United Kingdom (n=209) respectively. Although further international and national standardisation in both English and other languages is recommended, factor and reliability analyses indicated satisfactory validity and reliability of the current English version of the scale

Neurophysiologic, psychological, sport and health dimensions of three meditation techniques

The aim of this study was to record experiences of three meditation conditions: Ratio Breathing, Transcendental Meditation and Zazen, with special reference to sport, health, neuro-physiology and sense of coherence. The participants (N=9), seven males and two females were all British, actively competing across a range of individual and team sports, with no experience of using meditation techniques or practices in their sporting or daily lives. Their mean age was 31.56 years with an age range of 22 to 44 years. The study employed a within-subjects, repeated measures design, with each participant practising each meditation condition in a randomly counterbalanced order. Integrative findings support the value of all three meditation conditions for health and to a lesser extent for sport, especially with regard to their effect on focus. All three meditation conditions were associated with a decrease in respiration. The differential effect of the meditations was apparent. Participants valued Ratio breathing for its effect on concentration, Transcendental Meditation for its depth of meditation and Zazen for its effect on self and removal of external distractions. These qualitative findings were associated with differentially significant quantitative effects on lowered respiration rate in the Ratio Breathing group, increased physical relaxation and alpha activity in the Transcendental Meditation group, and increases in both alpha and theta activity in the Zazen group