The genus <i>Lepidochitona</i> Gray, 1821 (Mollusca: Polyplacophora) in the northeastern Atlantic Ocean, the Mediterranean Sea and the Black Sea

Nine species of Lepidochitona from the NE Atlantic and adjacent seas are described, two of which are new to science: L. monterosatoi from the Mediterranean Sea, and L. iberica from Ria de Arosa, NW Spain. The taxa Middendorffia Dali, 1882, and Mopaliella Thiele, 1909, are rejected and synonymized with Lepidochitona Gray, 1821. Ischnochiton stroemfelti Bergenhayn, 1931, is recognized as an intermediate form between Ischnochiton Gray, 1847, and Lepidochitona Gray, 1821, classed with the latter genus by the authors on account of several arguments

White box radial basis function classifiers with component selection for clinical prediction models

Objective: To propose a new flexible and sparse classifier that results in interpretable decision support systems. Methods: Support vector machines (SVMs) for classification are very powerful methods to obtain classifiers for complex problems. Although the performance of these methods is consistently high and non-linearities and interactions between variables can be handled efficiently when using non-linear kernels such as the radial basis function (RBF) kernel, their use in domains where interpretability is an issue is hampered by their lack of transparency. Many feature selection algorithms have been developed to allow for some interpretation but the impact of the different input variables on the prediction still remains unclear. Alternative models using additive kernels are restricted to main effects, reducing their usefulness in many applications. This paper proposes a new approach to expand the RBF kernel into interpretable and visualizable components, including main and two-way interaction effects. In order to obtain a sparse model representation, an iterative l-regularized parametric model using the interpretable components as inputs is proposed. Results: Results on toy problems illustrate the ability of the method to select the correct contributions and an improved performance over standard RBF classifiers in the presence of irrelevant input variables. For a 10-dimensional x-or problem, an SVM using the standard RBF kernel obtains an area under the receiver operating characteristic curve (AUC) of 0.947, whereas the proposed method achieves an AUC of 0.997. The latter additionally identifies the relevant components. In a second 10-dimensional artificial problem, the underlying class probability follows a logistic regression model. An SVM with the RBF kernel results in an AUC of 0.975, as apposed to 0.994 for the presented method. The proposed method is applied to two benchmark datasets: the Pima Indian diabetes and the Wisconsin Breast Cancer dataset. The AUC is in both cases comparable to those of the standard method (0.826 versus 0.826 and 0.990 versus 0.996) and those reported in the literature. The selected components are consistent with different approaches reported in other work. However, this method is able to visualize the effect of each of the components, allowing for interpretation of the learned logic by experts in the application domain. Conclusions: This work proposes a new method to obtain flexible and sparse risk prediction models. The proposed method performs as well as a support vector machine using the standard RBF kernel, but has the additional advantage that the resulting model can be interpreted by experts in the application domain. © 2013 Elsevier B.V

Establishing Visible Interferometer System Responses: Resolved and Unresolved Calibrators

The propagation of errors through the uniform disk visibility function is examined. Implications of those errors upon measures of absolute visibility through optical and near-infrared interferometers are considered within the context of using calibration stars to establish system visibilities for these instruments. We suggest a simple ratio test to establish empirically whether or not the measured visibilities produced by such an instrument are relative (errors dominated by calibrator angular size prediction error) or absolute (errors dominated by measurement error).Comment: 20 pages, 7 figures, to be published in the PAS

Monitoring and Management of Childhood Asthma in Asian Countries

BACKGROUND: A recent study by the International Study of Asthma and Allergies in Childhood has shown that asthma symptom prevalence is still increasing in parts of Asia. As such, it is important to know how well asthma is being managed. Practices of physicians in India, China, Sri Lanka, Australia, Singapore, Indonesia, Philippines, and Taiwan in monitoring and treating childhood asthma were examined. METHODS: A 6-page standardized questionnaire was sent to physicians via post. The questionnaire is made up of 3 parts, including (1) methods of monitoring of childhood asthma, (2) practices in managing acute asthma exacerbations, and (3) choice of therapy in maintenance treatment. RESULTS: Our study reflects mostly the practices of physicians who practice in urban regions. Of respondents, 41.4% were general pediatricians, whereas 26.3% were general practitioners. A small fraction of physicians used score cards or diaries to monitor asthma, ranging from 0% (Philippines and Australia) to 15.9% (India). Only 8.1% (Sri Lanka) to 52.0% (Australia) use either a peak flow meter and/or spirometry to monitor asthma. However, for frequency of use, 35% (China) to 94% (Indonesia) never or seldom make use of a peak flow meter, and 33% (China) to 97.6% (Indonesia) never or seldom use spirometry for monitoring. Most physicians treat acute asthma appropriately with short-acting bronchodilators. For maintenance treatment, an inhaled corticosteroid was the most frequently chosen first-choice therapy. However, a significant fraction of physicians chose a long-acting β-agonist monotherapy as a first-choice treatment for asthma maintenance. For infants, the percentage ranged from 1.4% (Australia) to 76.3% (Indonesia); in preschoolers, 1.8% (Australia) to 43.3% (Indonesia); and in older children, 0% (Philippines) to 28.8% (Indonesia). These results may be related to the overall affluence of each nation. CONCLUSIONS: There is much room for improvement in increasing physicians' awareness to guidelines for more effective management of pediatric asthma in Southeast Asia, especially regarding the high use of long-acting β-agonist monotherapy, even in young children

The dynamic atmospheres of Mira stars: comparing the CODEX models to PTI time series of TU And

Our comprehension of stellar evolution on the AGB still faces many difficulties. To improve on this, a quantified understanding of large-amplitude pulsator atmospheres and interpretation in terms of their fundamental stellar parameters are essential. We wish to evaluate the effectiveness of the recently released CODEX dynamical model atmospheres in representing M-type Mira variables through a confrontation with the time-resolved spectro-photometric and interferometric PTI data set of TU And. We calibrated the interferometric K-band time series to high precision. This results in 50 nights of observations, covering 8 subsequent pulsation cycles. At each phase, the flux at 2.2$\mu$m is obtained, along with the spectral shape and visibility points in 5 channels across the K-band. We compared the data set to the relevant dynamical, self-excited CODEX models. Both spectrum and visibilities are consistently reproduced at visual minimum phases. Near maximum, our observations show that the current models predict a photosphere that is too compact and hot, and we find that the extended atmosphere lacks H2O opacity. Since coverage in model parameter space is currently poor, more models are needed to make firm conclusions on the cause of the discrepancies. We argue that for TU And, the discrepancy could be lifted by adopting a lower value of the mixing length parameter combined with an increase in the stellar mass and/or a decrease in metallicity, but this requires the release of an extended model grid.Comment: 5 pages, 5 figures, accepted for publication in A&A Letter

Spitzer Space Telescope Observations of Circumbinary Dust Disks around Polars

We present Spitzer Space Telescope IRAC photometry of the magnetic cataclysmic variables EF Eri, MR Ser, VV Pup, V834 Cen, GG Leo and V347 Pav. When we combine our results with the 2MASS data, we find that at least five of the polars have flux densities in the mid-IR in excess of the emission expected from the stellar components alone. We are unable to model this mid-IR excess with cyclotron emission, but we can recreate the observed spectral energy distributions with the inclusion of a simple circumbinary dust disk model. Importantly, we find that the masses of our modelled disks are approximately 12 orders of magnitude lower than required to significantly affect CV evolution. The accretion disk-less polars are ideal places to search for these disks, since the luminous accretion disk in most CVs would drown out the faint IR signature of the cooler, dimmer circumbinary disks