3,385 research outputs found
Recreation value of a new long-distance walking track
A large recreation value may be expected for a long-distance walking track which allows for hiking and camping in a tropical rainforest environment. When such a resource is new, sufficient data are not available for a primary study. A practical way to obtain a value estimate is by employing benefit transfer procedures. Using a travel cost analysis for the Thorsborne Trail as the transfer source, a consumer surplus estimate for the new Cannabullen Track was estimated at about Aus$300 per person per year. This value may contribute to management decisions about further development of facilities along the track and about user fees
Post-activation performance enhancement in sprinters: effects of hard versus sand surfaces
Abstract This study aimed to compare the post-activation performance enhancement induced by successive drop-jumps performed on hard and sand surfaces in sprint and jump performance of top-level sprinters. Athletes were tested on two occasions. On each visit they were allocated to one of the experimental protocols, which consisted of performing 2x5 drop-jumps from a box with the height of 60-cm on hard or sand surfaces in randomized order, seven days apart. Prior to and 7 and 15-min after executing drop-jumps, sprinters performed countermovement jumps and 60-m sprint tests. Differences between sprinting splits and surfaces were assessed using a two-way analysis of variance with repeated measures. No significant differences in jump height or sprint time were observed (p>0.05), regardless of the surface used (i.e., hard or sand) during the conditioning activity (effect sizes [95% confidence intervals] ranging from 0.01 [-0.84;0.84] to 0.44 [-0.42;1.27]). Performing drop-jumps on sand or hard surfaces immediately before maximum sprinting bouts does not provide any advantage or disadvantage to top-level sprinters. Sprint coaches may prescribe short-plyometric training activities on sand surfaces even close to competitions, bearing in mind that this strategy will not compromise sprint-specific performance
The Excitation Wavelength and Solvent Dependance of the Kinetics of Electron Injection in Ru(dcbpy)2(NCS)2 Sensitized Nanocrystalline TiO2 Films
A burst search for gravitational waves from binary black holes
Compact binary coalescence (CBC) is one of the most promising sources of
gravitational waves. These sources are usually searched for with matched
filters which require accurate calculation of the GW waveforms and generation
of large template banks. We present a complementary search technique based on
algorithms used in un-modeled searches. Initially designed for detection of
un-modeled bursts, which can span a very large set of waveform morphologies,
the search algorithm presented here is constrained for targeted detection of
the smaller subset of CBC signals. The constraint is based on the assumption of
elliptical polarisation for signals received at the detector. We expect that
the algorithm is sensitive to CBC signals in a wide range of masses, mass
ratios, and spin parameters. In preparation for the analysis of data from the
fifth LIGO-Virgo science run (S5), we performed preliminary studies of the
algorithm on test data. We present the sensitivity of the search to different
types of simulated CBC waveforms. Also, we discuss how to extend the results of
the test run into a search over all of the current LIGO-Virgo data set.Comment: 12 pages, 4 figures, 2 tables, submitted for publication in CQG in
the special issue for the conference proceedings of GWDAW13; corrected some
typos, addressed some minor reviewer comments one section restructured and
references updated and correcte
Baseline ecological data collection from the marine area around Filfla (Malta, Central Mediterranean Sea)
Acoustic and limited video sampling were carried out in a 1.1 nautical mile-radius area
around Filfla, an islet 4.4 to the south-west of Malta, to characterize the benthos and the habitat type
distribution. In addition, identified priority areas were sampled during SCUBA diving surveys. A total of
173 species were recorded during the current survey. Rhodophytes were the most represented (29 species),
followed by molluscs (25 species). The biotic assemblages recorded from the marine area around Filfla are
generally representative of those found in Maltese inshore waters.peer-reviewe
The UK clinical aptitude test and clinical course performance at Nottingham: a prospective cohort study
Background
The UK Clinical Aptitude Test (UKCAT) was introduced in 2006 as an additional tool for the selection of medical students. It tests mental ability in four distinct domains (Verbal Reasoning, Quantitative Reasoning, Abstract Reasoning, and Decision Analysis), and the results are available to students and admission panels in advance of the selection process. Our first study showed little evidence of any predictive validity for performance in the first two years of the Nottingham undergraduate course.
The study objective was to determine whether the UKCAT scores had any predictive value for the later parts of the course, largely delivered via clinical placements.
Methods
Students entering the course in 2007 and who had taken the UKCAT were asked for permission to use their anonymised data in research. The UKCAT scores were incorporated into a database with routine pre-admission socio-demographics and subsequent course performance data. Correlation analysis was followed by hierarchical multivariate linear regression.
Results
The original study group comprised 204/254 (80%) of the full entry cohort. With attrition over the five years of the course this fell to 185 (73%) by Year 5. The Verbal Reasoning score and the UKCAT Total score both demonstrated some univariate correlations with clinical knowledge marks, and slightly less with clinical skills. No parts of the UKCAT proved to be an independent predictor of clinical course marks, whereas prior attainment was a highly significant predictor (p <0.001).
Conclusions
This study of one cohort of Nottingham medical students showed that UKCAT scores at admission did not independently predict subsequent performance on the course. Whilst the test adds another dimension to the selection process, its fairness and validity in selecting promising students remains unproven, and requires wider investigation and debate by other schools
Microscopic Derivation of Non-Markovian Thermalization of a Brownian Particle
In this paper, the first microscopic approach to the Brownian motion is
developed in the case where the mass density of the suspending bath is of the
same order of magnitude as that of the Brownian (B) particle. Starting from an
extended Boltzmann equation, which describes correctly the interaction with the
fluid, we derive systematicaly via the multiple time-scale analysis a reduced
equation controlling the thermalization of the B particle, i.e. the relaxation
towards the Maxwell distribution in velocity space. In contradistinction to the
Fokker-Planck equation, the derived new evolution equation is non-local both in
time and in velocity space, owing to correlated recollision events between the
fluid and particle B. In the long-time limit, it describes a non-markovian
generalized Ornstein-Uhlenbeck process. However, in spite of this complex
dynamical behaviour, the Stokes-Einstein law relating the friction and
diffusion coefficients is shown to remain valid. A microscopic expression for
the friction coefficient is derived, which acquires the form of the Stokes law
in the limit where the mean-free in the gas is small compared to the radius of
particle B.Comment: 28 pages, no figure, submitted to Journal of Statistical Physic
Networks of gravitational wave detectors and three figures of merit
This paper develops a general framework for studying the effectiveness of
networks of interferometric gravitational wave detectors and then uses it to
show that enlarging the existing LIGO-VIRGO network with one or more planned or
proposed detectors in Japan (LCGT), Australia, and India brings major benefits,
including much larger detection rate increases than previously thought... I
show that there is a universal probability distribution function (pdf) for
detected SNR values, which implies that the most likely SNR value of the first
detected event will be 1.26 times the search threshold. For binary systems, I
also derive the universal pdf for detected values of the orbital inclination,
taking into account the Malmquist bias; this implies that the number of
gamma-ray bursts associated with detected binary coalescences should be 3.4
times larger than expected from just the beaming fraction of the gamma burst.
Using network antenna patterns, I propose three figures of merit that
characterize the relative performance of different networks... Adding {\em any}
new site to the planned LIGO-VIRGO network can dramatically increase, by
factors of 2 to 4, the detected event rate by allowing coherent data analysis
to reduce the spurious instrumental coincident background. Moving one of the
LIGO detectors to Australia additionally improves direction-finding by a factor
of 4 or more. Adding LCGT to the original LIGO-VIRGO network not only improves
direction-finding but will further increase the detection rate over the
extra-site gain by factors of almost 2, partly by improving the network duty
cycle... Enlarged advanced networks could look forward to detecting three to
four hundred neutron star binary coalescences per year.Comment: 38 pages, 7 figures, 2 tables. Accepted for publication in Classical
and Quantum Gravit
Implementing a new mathematics curriculum in England: district Research Lesson Study as a driver for student learning, teacher learning and professional dialogue.
Against a backdrop of a transformation in teacher professional development and learning and state school organisation in England this century, this chapter describes a project which harnessed six cycles of Research Lesson Study at school and district level over two years to tailor the implementation of a new statutory curriculum in England to address the professional development needs of teachers and classroom learning needs of London students. It also reports the findings of research carried out during the project into how these teachers learned and developed this new curricular expertise and practice- knowledge through lesson study dialogues that supported student learning. It concludes by proposing future directions for teacher professional learning research and practice
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