230 research outputs found
Biophysical assessment of reefs in Keppel Bay: a baseline study (April 2007)
The Keppel Islands are a group of 16 continental islands lying 18 km off the coastal town of Yeppoon in the southern Great Barrier Reef. Located in the shallow basin to the north of Keppel Bay, the islands are host to a patchwork of fringing reefs in various forms of development. Coral communities are abundant in some locations, and coral cover is high (60 to 70%) relative to the average at sites surveyed by the Australian Institute of Marine Scienceâs Long-Term Monitoring Program (~35%), and are often dominated by extensive stands of branching Acropora that extend into shallow water. These âstaghornâ corals are vulnerable to impacts caused by environmental stresses such as elevated sea temperature (causing coral bleaching events), degraded water quality (associated with hyposaline floods events) and physical damage (from cyclones, storms and anchoring). The Fitzroy River, one of the largest catchments in Queensland, is about 40 km to the south of the Keppel Islands. Large flood plumes occur approximately every 10 years, and the soft riverine sediments are regularly re-suspended in the shallow bay by wind and tide action causing high turbidity. Heavy rainfall also affects the shallow reef flat habitats, with reported incidences of coral mortality caused by heavy rain at times of extreme low tidesID: 176
The two-dimensional random-bond Ising model, free fermions and the network model
We develop a recently-proposed mapping of the two-dimensional Ising model
with random exchange (RBIM), via the transfer matrix, to a network model for a
disordered system of non-interacting fermions. The RBIM transforms in this way
to a localisation problem belonging to one of a set of non-standard symmetry
classes, known as class D; the transition between paramagnet and ferromagnet is
equivalent to a delocalisation transition between an insulator and a quantum
Hall conductor. We establish the mapping as an exact and efficient tool for
numerical analysis: using it, the computational effort required to study a
system of width is proportional to , and not exponential in as
with conventional algorithms. We show how the approach may be used to calculate
for the RBIM: the free energy; typical correlation lengths in quasi-one
dimension for both the spin and the disorder operators; even powers of
spin-spin correlation functions and their disorder-averages. We examine in
detail the square-lattice, nearest-neighbour RBIM, in which bonds are
independently antiferromagnetic with probability , and ferromagnetic with
probability . Studying temperatures , we obtain precise
coordinates in the plane for points on the phase boundary between
ferromagnet and paramagnet, and for the multicritical (Nishimori) point. We
demonstrate scaling flow towards the pure Ising fixed point at small , and
determine critical exponents at the multicritical point.Comment: 20 pages, 25 figures, figures correcte
Physical fitness in people with a spinal cord injury: the association with complications and duration of rehabilitation.
Objective: To assess the association between physical fitness and its recovery over time on the one hand, and complications and duration of phases of rehabilitation on the other. Design and setting: Prospective cohort study at eight rehabilitation centres. Subjects: People with a spinal cord injury were assessed four times: at the start of active rehabilitation (n = 110), three months later (n = 92), at discharge (n = 137) and a year after discharge from inpatient rehabilitation (n = 91). Main measures: Physical fitness was defined as aerobic capacity, determined at each occasion by the peak oxygen uptake (peak V
Mitochondrial localization and function of a subset of 22q11 deletion syndrome candidate genes
Six genes in the 1.5 MB region of chromosome 22 deleted in DiGeorge/22q11 Deletion SyndromeâMrpl40, Prodh, Slc25a1, Txnrd2, T10, and Zdhhc8âencode mitochondrial proteins. All six genes are expressed in the brain, and maximal expression coincides with peak forebrain synaptogenesis shortly after birth. Furthermore, their protein products are associated with brain mitochondria, including those in synaptic terminals. Among the six, only Zddhc8 influences mitochondria-regulated apoptosis when overexpressed, and appears to interact biochemically with established mitochondrial proteins. Zdhhc8 has an apparent interaction with Uqcrc1, a component of mitochondrial complex III. The two proteins are coincidently expressed in presynaptic processes; however, Zdhhc8 is more frequently seen in glutamatergic terminals. 22q11 deletion may alter metabolic properties of cortical mitochondria during early post-natal life, since expression complex III components, including Uqcrc1, is significantly increased at birth in a mouse model of 22q11 deletion, and declines to normal values in adulthood. Our results suggest that altered dosage of one, or several 22q11 mitochondrial genes, particularly during early postnatal cortical development, may disrupt neuronal metabolism or synaptic signaling
The impact of introducing alcoholâfree beer options in bars and public houses on alcohol sales and revenue: a randomised crossover field trial
Aims: The study aimed to estimate the impact of introducing a draught alcoholâfree beer, thereby increasing the relative availability of these products, on alcohol sales and monetary takings in bars and pubs in England. Design: Randomised crossover field trial. Setting: England. Participants: Fourteen venues that did not previously sell draught alcoholâfree beer. Intervention and comparator: Venues completed two intervention periods and two control periods in a randomised order over 8 weeks. Intervention periods involved replacing one draught alcoholic beer with an alcoholâfree beer. Control periods operated business as usual. Measurements: The primary outcome was mean weekly volume (in litres) of draught alcoholic beer sold. The secondary outcome was mean weekly revenue [in GBP (ÂŁ)] from all drinks. Analyses adjusted for randomised order, special events, season and busyness. Findings: The adjusted mean difference in weekly sales of draught alcoholic beer was â20 L [95% confidence interval (CI) = â41 to +0.4], equivalent to a 4% reduction (95% CI = 8% reduction to 0.1% increase) in the volume of alcoholic draught beer sold when draught alcoholâfree beer was available. Excluding venues that failed at least one fidelity check resulted in an adjusted mean difference of â29 L per week (95% CI = â53 to â5), equivalent to a 5% reduction (95% CI = 8% reduction to 0.8% reduction). The adjusted mean difference in weekly revenue was +61 GBP per week (95% CI = â328 to +450), equivalent to a 1% increase (95% CI = 5% decrease to 7% increase) when draught alcoholâfree beer was available. Conclusions: Introducing a draught alcoholâfree beer in bars and pubs in England reduced the volume of draught alcoholic beer sold by 4% to 5%, with no evidence of the intervention impacting net revenue
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Teaching modern foreign languages in multilingual classrooms: an examination of Key Stage 2 teachersâ experiences
The statutory inclusion of modern foreign languages (MFL) into the Key Stage 2 curriculum in England in 2014 aimed to raise the language skills of younger learners in preparation for their secondary education. This change to the curriculum has occurred at a time in which the linguistic diversity within primary schools across the country has been consistently increasing. This study used Interpretative Phenomenological Analysis to qualitatively examine the impact of the curriculum change on teachers
implementing it in multilingual classrooms in Greater Manchester. Six teachers with varying experience in teaching MFL participated in semistructured interviews focussing on different aspects of the curriculum change. This paper focuses on the teaching of MFL, as well as on
teachersâ perceptions of English as an Additional Language (EAL) pupilsâ aptitude for language learning in comparison to their monolingual peers. The superordinate themes identified from the data included the inconsistent delivery of MFL in primary schools, and the role of
multilingual classrooms as opportunities for augmented MFL provision. The findings from this study will have implications for teachers, head teachers, and policy-makers regarding the effectiveness of the initial
implementation of MFL into the primary curriculum, with specific reference to the EAL school population
Analytical Results for Individual and Group Selection of Any Intensity
The idea of evolutionary game theory is to relate the payoff of a game to reproductive success (=âfitness). An underlying assumption in most models is that fitness is a linear function of the payoff. For stochastic evolutionary dynamics in finite populations, this leads to analytical results in the limit of weak selection, where the game has a small effect on overall fitness. But this linear function makes the analysis of strong selection difficult. Here, we show that analytical results can be obtained for any intensity of selection, if fitness is defined as an exponential function of payoff. This approach also works for group selection (=âmulti-level selection). We discuss the difference between our approach and that of inclusive fitness theory
Measurement of the branching fraction
The branching fraction is measured in a data sample
corresponding to 0.41 of integrated luminosity collected with the LHCb
detector at the LHC. This channel is sensitive to the penguin contributions
affecting the sin2 measurement from The
time-integrated branching fraction is measured to be . This is the most precise measurement to
date
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