Simultaneous multi-band detection of Low Surface Brightness galaxies with Markovian modelling

We present an algorithm for the detection of Low Surface Brightness (LSB) galaxies in images, called MARSIAA (MARkovian Software for Image Analysis in Astronomy), which is based on multi-scale Markovian modeling. MARSIAA can be applied simultaneously to different bands. It segments an image into a user-defined number of classes, according to their surface brightness and surroundings - typically, one or two classes contain the LSB structures. We have developed an algorithm, called DetectLSB, which allows the efficient identification of LSB galaxies from among the candidate sources selected by MARSIAA. To assess the robustness of our method, the method was applied to a set of 18 B and I band images (covering 1.3 square degrees in total) of the Virgo cluster. To further assess the completeness of the results of our method, both MARSIAA, SExtractor, and DetectLSB were applied to search for (i) mock Virgo LSB galaxies inserted into a set of deep Next Generation Virgo Survey (NGVS) gri-band subimages and (ii) Virgo LSB galaxies identified by eye in a full set of NGVS square degree gri images. MARSIAA/DetectLSB recovered ~20% more mock LSB galaxies and ~40% more LSB galaxies identified by eye than SExtractor/DetectLSB. With a 90% fraction of false positives from an entirely unsupervised pipeline, a completeness of 90% is reached for sources with r_e > 3" at a mean surface brightness level of mu_g=27.7 mag/arcsec^2 and a central surface brightness of mu^0 g=26.7 mag/arcsec^2. About 10% of the false positives are artifacts, the rest being background galaxies. We have found our method to be complementary to the application of matched filters and an optimized use of SExtractor, and to have the following advantages: it is scale-free, can be applied simultaneously to several bands, and is well adapted for crowded regions on the sky.Comment: 39 pages, 18 figures, accepted for publication in A

Retinoic Acid Causes Premature Desquamation of Cells from Confluent Cultures of Stratified Squamous Epithelia

Cells from 2 types of stratified squamous epithelia were grown to confluence in vitro. In these cultures highly differentiated cells were shed into the culture medium at a constant rate for at least 4weeks, thus providing a unique system in which to study factors that influence desquamation. Retinoic acid (RA) decreased the rate of desquamation in calf esophagus epithelial cell (CEEC) cultures and increased the rate of desquamation in human foreskin epithelial cell (HFEC) cultures. Cells shed from CEEC and HFEC cultures treated with RA were less differentiated, as assessed by their protein/DNA ratio, than cells shed from control cultures. These data indicate that retinoic acid induces premature desquamation from stratified squamous epithelia

Towards a merged satellite and in situ fluorescence ocean chlorophyll product

Understanding the ocean carbon cycle requires a precise assessment of phytoplankton biomass in the oceans. In terms of numbers of observations, satellite data represent the largest available data set. However, as they are limited to surface waters, they have to be merged with in situ observations. Amongst the in situ data, fluorescence profiles constitute the greatest data set available, because fluorometers have operated routinely on oceanographic cruises since the 1970s. Nevertheless, fluorescence is only a proxy of the total chlorophyll <i>a</i> concentration and a data calibration is required. Calibration issues are, however, sources of uncertainty, and they have prevented a systematic and wide range exploitation of the fluorescence data set. In particular, very few attempts to standardize the fluorescence databases have been made. Consequently, merged estimations with other data sources (e.g. satellite) are lacking. <br><br> We propose a merging method to fill this gap. It consists firstly in adjusting the fluorescence profile to impose a zero chlorophyll <i>a</i> concentration at depth. Secondly, each point of the fluorescence profile is then multiplied by a correction coefficient, which forces the chlorophyll <i>a</i> integrated content measured on the fluorescence profile to be consistent with the concomitant ocean colour observation. The method is close to the approach proposed by Boss et al. (2008) to correct fluorescence data of a profiling float, although important differences do exist. To develop and test our approach, in situ data from three open ocean stations (BATS, HOT and DYFAMED) were used. Comparison of the so-called "satellite-corrected" fluorescence profiles with concomitant bottle-derived estimations of chlorophyll <i>a</i> concentration was performed to evaluate the final error (estimated at 31%). Comparison with the Boss et al. (2008) method, using a subset of the DYFAMED data set, demonstrated that the methods have similar accuracy. The method was applied to two different data sets to demonstrate its utility. Using fluorescence profiles at BATS, we show that the integration of "satellite-corrected" fluorescence profiles in chlorophyll <i>a</i> climatologies could improve both the statistical relevance of chlorophyll <i>a</i> averages and the vertical structure of the chlorophyll <i>a</i> field. We also show that our method could be efficiently used to process, within near-real time, profiles obtained by a fluorometer deployed on autonomous platforms, in our case a bio-optical profiling float. The application of the proposed method should provide a first step towards the generation of a merged satellite/fluorescence chlorophyll <i>a</i> product, as the "satellite-corrected" profiles should then be consistent with satellite observations. Improved climatologies with more consistent satellite and in situ data are likely to enhance the performance of present biogeochemical models

The 2006 July 17 Java (Indonesia) tsunami from satellite imagery and numerical modelling: A single or complex source?

The Mw 7.8 2006 July 17 earthquake off the southern coast of Java, Indonesia, has been responsible for a very large tsunami causing more than 700 casualties. The tsunami has been observed on at least 200 km of coastline in the region of Pangandaran (Wes

Autonomic pain responses during sleep: a study of heart rate variability

The autonomic nervous system (ANS) reacts to nociceptive stimulation during sleep, but whether this reaction is contingent to cortical arousal, and whether one of the autonomic arms (sympathetic/parasympathetic) predominates over the other remains unknown. We assessed ANS reactivity to nociceptive stimulation during all sleep stages through heart rate variability, and correlated the results with the presence of cortical arousal measured in concomitant 32-channel EEG. Fourteen healthy volunteers underwent whole-night polysomnography during which nociceptive laser stimuli were applied over the hand. RR intervals (RR) and spectral analysis by wavelet transform were performed to assess parasympathetic (HF(WV)) and sympathetic (LF(WV) and LF(WV)/HF(WV) ratio) reactivity. During all sleep stages, RR significantly decreased in reaction to nociceptive stimulations, reaching a level similar to that of wakefulness, at the 3rd beat post-stimulus and returning to baseline after seven beats. This RR decrease was associated with an increase in sympathetic LF(WV) and LF(WV)/HF(WV) ratio without any parasympathetic HF(WV) change. Albeit RR decrease existed even in the absence of arousals, it was significantly higher when an arousal followed the noxious stimulus. These results suggest that the sympathetic-dependent cardiac activation induced by nociceptive stimuli is modulated by a sleep dependent phenomenon related to cortical activation and not by sleep itself, since it reaches a same intensity whatever the state of vigilance

Student Self-Screening for Methicillin-Resistant Staphylococcus Aureus (MRSA) Nasal Colonization in Hand Hygiene Education

Objective. To determine the feasibility and effectiveness of adding a hand hygiene exercise in self-screening for Methicillin-Resistant Staphylococcus Aureus (MRSA) nasal colonization to a health care delivery course for first-year pharmacy (P1) students. Design. About one month after students were trained in hand hygiene technique and indications, faculty members demonstrated how to self-screen for MRSA nasal colonization. Students were then asked to screen themselves during the required class time. Aggregated class results were shared and compared to prevalence estimates for the general population and health care providers. Assessment. The 71 students present in class on the day of the self-screening exercise chose to participate. A survey comparing presecreening and postscreening responses indicated incremental improvements in student knowledge and awareness of health care associated infections and motivation to perform hand hygiene. On the written exam, student performance demonstrated improved knowledge compared to previous class years. Conclusion. Self-screening for MRSA nasal colonization in a health care delivery course for P1 students increased students’ motivation to perform hand hygiene techniques and follow indications promulgated by the World Health Organization

Programa para potenciar el desarrollo del funcionamiento ejecutivo en las aulas de educación primaria: PIEFE

En la última década se está observando un interés creciente por el estudio de los procesos y funciones del sistema ejecutivo, no solo a nivel neurobiopsicológico sino en cuanto al efecto que tienen sobre el desarrollo y el aprendizaje en el ser humano. En el entorno escolar, los programas de estimulación del funcionamiento ejecutivo han sido diseñados fundamentalmente para ser aplicados con población que presenta necesidades específicas de apoyo educativo, sin embargo, consideramos que podría ser muy beneficioso poder aplicarlos en un aula ordinaria con todo el alumnado. En esta línea se sitúan los estudios de Romero, Benavides, Fernández y Pichardo (2017); y los de Chen, Yue, Tian y Jiang (2016), quienes han diseñado programas para aplicar en aulas de Educación Infantil y en la Universidad respectivamente. En Educación Primaria se han utilizado algunas herramientas que han resultado ser eficaces en el desarrollo del funcionamiento ejecutivo (Bodrova y Leong, 2007), sin embargo, la mayoría presentan escasa validez ecológica. De esta necesidad, y de la de trabajar con todo el alumnado de 1º a 6º de Educación Primaria, surge el objetivo del presente trabajo, diseñar un Programa de Intervención Escolar en Funciones Ejecutivas (“PIEFE”), inspirado en el Programa de Intervención para la mejora de los procesos del Sistema Ejecutivo y sus Funciones (“PISEFEs”) basado en el modelo teórico de Lavigne y Romero (2009). El objetivo que persigue el Programa es, por un lado, estimular los procesos psicológicos del Sistema Ejecutivo –Control Ejecutivo del Comportamiento, la Memoria de Trabajo y la Autorregulación de la Motivación y del Afecto- y sus Funciones -planificación/ organización, automonitorización/ evaluación y flexibilidad-, en niños y niñas con edades comprendidas entre los 6 y los 12 años y, por otro lado, desarrollar un programa complementario para formar a padres, madres y docentes

Early-season predation on aphids by winter-active spiders in apple orchards revealed by diagnostic PCR

Aphids are major pests in apple orchards, debilitating the crop and spreading disease. We investigated whether early-season predation by canopy spiders may be effectively controlling aphid numbers in three organic orchards. For this purpose, we monitored the aphid population dynamics from the winter eggs to colony stages and compared this to spider abundances and rates of predation on aphids detected by diagnostic polymerase chain reaction. For the latter, we applied existing general aphid primers. We found that spiders ate colony fundatrices and that aphid numbers were negatively related to spider abundance. Spiders were the main active predators within the orchards when the first colony fundatrices were present, indicating their importance in the early control of aphid populations

Nemaline bodies as unique pathological feature in the course of treated dermatomyositis.

Dermatomyositis was diagnosed on clinical and muscle histological criteria in a 42-year-old woman. Despite treatment, the patient complained of deterioration of her muscle condition. Since her symptoms were discordant with the rest of the data, muscle biopsy was performed and disclosed rod-bearing non-atrophic fibers as the unique and predominant pathological feature. Their significance is examined in this paper