1,192 research outputs found
Some aspects of the ecology of the ringed plover(charadrius hlaticula) during the breeding season.
The Ringed Plover Gharadrlus hiaticula was studied during a period of fieldwork in 1979. Data from this and other studies are used in consideration of certain aspects of the ecology of the species during the breeding season. There were two main areas of study, the mainland (Ross Back Sands, Old Law and Badle Bay) and the island (Lindisfarne).Territories were taken up earlier on the mainland. There was a fall in the. number of territories occupied in 1979, compared to previous years. There is good evidence for site tenacity, with many pairs occupying the same or an adjacent territory year after year. The minimum length of territory occupancy ranged from 15 to more than 94 days. The first egg of 1979 was laid on 2 May. The clutches were of 3 or 4 eggs. The peak of laying and the amount of laying per pair varies from year to-year. The final clutch of 1979 was recorded on 18 July. The interval between territory uptake and the laying of the first egg was longer, the earlier the territory was established. 85% of eggs noted were predated in 1979.The major agent of egg predation was crows. The period of hatching lasts from May to August, The incubation period is usually from 22 to 26 days. The fledging success of 1979 was between 5.8 and 12.57% of eggs laid. The birds spend most of their time feeding on the drier areas of the beach. Invertebrate samples showed much greater potential prey on wet mud areas than on drier sand or muddy-sand areas. Females feed faster than males
A simple formula for pooling knowledge about a quantum system
When various observers obtain information in an independent fashion about a
classical system, there is a simple rule which allows them to pool their
knowledge, and this requires only the states-of-knowledge of the respective
observers. Here we derive an equivalent quantum formula. While its realm of
applicability is necessarily more limited, it does apply to a large class of
measurements, and we show explicitly for a single qubit that it satisfies the
intuitive notions of what it means to pool knowledge about a quantum system.
This analysis also provides a physical interpretation for the trace of the
product of two density matrices.Comment: 5 pages, Revtex
ST2 and Multimarker Testing in Acute Decompensated Heart Failure
Most data on heart failure biomarkers have been derived from patient cohorts with chronic disease. However, risk prediction in patients admitted with acute decompensated heart failure (ADHF) remains a challenge. ADHF is not a single disease: it presents in various manners, and different causes may underlie ADHF, which may be reflected by different biomarkers. Soluble suppression of tumorigenicity 2 (ST2) has been shown to be a strong independent predictor of short-, mid-, and long-term outcome in ADHF. Furthermore, combining biomarkers may help further improve the prognostic power of ST2. The ProBNP Investigation of Dyspnea in the Emergency Department study showed that elevated plasma levels of ST2 together with elevated levels of 4 other biomarkers have clear incremental values to predict outcome in ADHF. The Multinational Observational Cohort on Acute Heart Failure study is an international collaborative network that recruited 5,306 patients hospitalized for ADHF that demonstrated that ST2 and midregional pro-adrenomedulin had independently strong value to predict 30-day and 1-year outcome in patients with ADHF. The Multinational Observational Cohort on Acute Heart Failure study also showed that C-reactive protein plus ST2 better classified risk in patients with ADHFs than ST2 alone. Combining biomarkers for risk prediction or risk stratification might have clinical and more importantly pathophysiological meaning
African immigrant parents\u27 understanding of their teenager\u27s newly diagnosed diabetes status in Western Australia
Background: Recently Western Australia has seen a rise in African population due to both economic and refugee migration. Concurrently, a rise in the numbers of teenagers of African origin diagnosed with both type 1 and type 2 diabetes and associated complications has been noticeable. Different ethnic background is a known risk factor for poor metabolic control; this trend is reflected in studies wherein people of African origin have been found to have a high risk of developing diabetes. What is evident from health promotion literature is that parents of teenagers with a chronic health condition, when they are well informed about that condition, play a key part its management. Little is known, though, about what African migrant parents understand about diabetes and its dietary control
Are mesenchymal stem cells and derived extracellular vesicles valuable to halt the COVID-19 inflammatory cascade? Current evidence and future perspectives
A difference boosting neural network for automated star-galaxy classification
In this paper we describe the use of a new artificial neural network, called
the difference boosting neural network (DBNN), for automated classification
problems in astronomical data analysis. We illustrate the capabilities of the
network by applying it to star galaxy classification using recently released,
deep imaging data. We have compared our results with classification made by the
widely used Source Extractor (SExtractor) package. We show that while the
performance of the DBNN in star-galaxy classification is comparable to that of
SExtractor, it has the advantage of significantly higher speed and flexibility
during training as well as classification.Comment: 9 pages, 1figure, 7 tables, accepted for publication in Astronomy and
Astrophysic
Potential role for clinical calibration to increase engagement with and application of home telemonitoring: a report from the HeartCycle programme
Aims: There is a need for alternative strategies that might avoid recurrent admissions in patients with heart failure. Home Telemonitoring (HTM) to monitor patient’s symptoms from a distance may be useful. This study attempts to assess changes in HTM vital signs in response to daily life activities (variations in medication, salt intake, exercise and stress) and to stablish which variations affect weight, blood pressure (BP) and heart rate (HR). Methods and results: We assessed 76 patients with heart failure (mean age 76 ± 10.8 years, 75% male, mainly in NYHA class II/III and from ischaemic etiology cause). Patients were given a calendar of interventions scheduling activities approximately twice-a-week before measuring their vital signs. Eating salty food or a large meal were the activities that had a significant impact on weight gain (+0.3 kg; p<0.001 and p=0.006, respectively). Exercise and skipping a dose of medication other than diuretics increased heart rate (+3 bpm, p=0.001 and almost +2 bpm, p=0.016, respectively). Conclusions: Our HTM system was able to detect small changes in vital signs related to these activities. Further studies should assess if providing such a schedule of activities might be useful for patient education and could improve long-term adherence to recommended lifestyle changes
Fitting in a complex chi^2 landscape using an optimized hypersurface sampling
Fitting a data set with a parametrized model can be seen geometrically as
finding the global minimum of the chi^2 hypersurface, depending on a set of
parameters {P_i}. This is usually done using the Levenberg-Marquardt algorithm.
The main drawback of this algorithm is that despite of its fast convergence, it
can get stuck if the parameters are not initialized close to the final
solution. We propose a modification of the Metropolis algorithm introducing a
parameter step tuning that optimizes the sampling of parameter space. The
ability of the parameter tuning algorithm together with simulated annealing to
find the global chi^2 hypersurface minimum, jumping across chi^2{P_i} barriers
when necessary, is demonstrated with synthetic functions and with real data
Forward Flux Sampling-type schemes for simulating rare events: Efficiency analysis
We analyse the efficiency of several simulation methods which we have
recently proposed for calculating rate constants for rare events in stochastic
dynamical systems, in or out of equilibrium. We derive analytical expressions
for the computational cost of using these methods, and for the statistical
error in the final estimate of the rate constant, for a given computational
cost. These expressions can be used to determine which method to use for a
given problem, to optimize the choice of parameters, and to evaluate the
significance of the results obtained. We apply the expressions to the
two-dimensional non-equilibrium rare event problem proposed by Maier and Stein.
For this problem, our analysis gives accurate quantitative predictions for the
computational efficiency of the three methods.Comment: 19 pages, 13 figure
Bayesian analysis of the astrobiological implications of life's early emergence on Earth
Life arose on Earth sometime in the first few hundred million years after the
young planet had cooled to the point that it could support water-based
organisms on its surface. The early emergence of life on Earth has been taken
as evidence that the probability of abiogenesis is high, if starting from
young-Earth-like conditions. We revisit this argument quantitatively in a
Bayesian statistical framework. By constructing a simple model of the
probability of abiogenesis, we calculate a Bayesian estimate of its posterior
probability, given the data that life emerged fairly early in Earth's history
and that, billions of years later, curious creatures noted this fact and
considered its implications. We find that, given only this very limited
empirical information, the choice of Bayesian prior for the abiogenesis
probability parameter has a dominant influence on the computed posterior
probability. Although terrestrial life's early emergence provides evidence that
life might be common in the Universe if early-Earth-like conditions are, the
evidence is inconclusive and indeed is consistent with an arbitrarily low
intrinsic probability of abiogenesis for plausible uninformative priors.
Finding a single case of life arising independently of our lineage (on Earth,
elsewhere in the Solar System, or on an extrasolar planet) would provide much
stronger evidence that abiogenesis is not extremely rare in the Universe.Comment: updated acknowledgement
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