Near-Earth Asteroids Data mining on Astronomical Databases: EuroNEAR experience

Program available at: http://www.imcce.fr/hosted_sites/naroo/program.htmlInternational audienceIn the framework of EuroNEAR network several databases around the world were datamined. The main scientifi c objective was the astrometry of Near-Earth Asteroids (NEAs) for both precovery and secure orbits of these objects. The article presents few aspects of data-mining and the developed procedures for accomplishing these objectives

The Role of the Chemoreceptor Zinc-Binding Domain in Bacterial Signal Transduction

49 pagesChemotaxis is the biochemical and cellular process by which bacteria sense particular molecules in their environment and adjust swimming behaviors accordingly. Chemotaxis and other motility alterations in response to endogenous HOCl (hypochlorous acid, also known as bleach) are known to be necessary behaviors by which bacteria locate nutritive niches within the human body, allowing them to survive and thrive. A wide variety of gut-colonizing bacteria, including pathogens such as Escherichia coli and Salmonella. enterica depend on the Chemoreceptor Zinc-Binding (CZB) domain to sense certain aspects of their environments and alter swimming patterns accordingly. Thus, understanding the biochemistry underlying CZB signal transduction has the potential to set the foundation for future therapeutics while also expanding our understanding of the ways in which bacteria survive the often-hostile context of the human body. While existing research treated the CZB domain as a zinc sensor, my work contends that in certain molecular and cellular contexts the domain acts as an HOCl sensor instead. My work shows that the CZB possesses a highly conserved, bleach-sensitive cysteine (1/2 oxidized at 312 µM bleach) and indicates that oxidation of this cysteine results in subtle yet observable structural changes to the CZB domain. In the context of H. pylori, the CZB domain likely allows the chemoreceptor transducer-like protein D (tlpD) to swim towards sites of inflammation and injury within the stomach, thus allowing the pathogen to reach a “safe harbor” within the human stomach. This behavior illustrates the possible significance of the CZB domain in human disease: pathogens may use the domain to sense sites of inflammation, which in many cases can indicate safe and nutritive niches for these pathogens. In other contexts, CZB bleach sensing may constitute the basis for bleach chemorepulsion, where bacteria may be able to flee this generally harmful molecule. Thus, CZB bleach sensing could underly an important first step in bacterial infection and proliferation, and thus constitute a target for future therapeutic efforts

Optical-near-IR analysis of globular clusters in the IKN dwarf spheroidal : a complex star formation history

Context. Age, metallicity, and spatial distribution of globular clusters (GCs) provide a powerful tool for reconstructing major starformation episodes in galaxies. IKN is a faint dwarf spheroidal (dSph) in the M 81 group of galaxies. It contains five old GCs, which makes it the galaxy with the highest known specific frequency (S N = 126). Aims. We estimate the photometric age, metallicity, and spatial distribution of the poorly studied IKN GCs. We search SDSS for GC candidates beyond the HST/ACS field of view, which covers half of IKN. Methods. To break the age-metallicity degeneracy in the VI colour, we used WHT/LIRIS KS-band photometry and derived photometric ages and metallicities by comparison with SSP models in the V; I; Ks colour space. Results. IKN GCs’ VIKs colours are consistent with old ages ( 8 Gyr) and a metallicity distribution with a higher mean than is typical for such a dSph ([Fe/H] ' 1:4+0:6 0:2 dex). Their photometric mass range (0:5 < MGC < 4 105 M ) implies an unusually high mass ratio between GCs and field stars, of 10:6%. Mixture model analysis of the RGB field stars’ metallicity suggests that 72% of the stars may have formed together with the GCs. Using the most massive GCSFR relation, we calculated a star formation rate (SFR) of 10 M =yr during its formation epoch. We note that the more massive GCs are closer to the galaxy photometric centre. IKN GCs also appear spatially aligned along a line close to the major axis of the IKN and nearly orthogonal to the plane of spatial distribution of galaxies in the M 81 group. We identify one new IKN GC candidate based on colour and the PSF analysis of the SDSS data Conclusions. The evidence of i) broad and high metallicity distribution of the field IKN RGB stars and its GCs, ii) high fraction, and iii) spatial alignment of IKN GCs supports a scenario for tidally triggered, complex IKN’s star formation history in the context of interactions with galaxies in the M 81 group

Security and Privacy for Cloud-Based Data Management in the Health Network Service Chain: A Microservice Approach

New and useful tools that facilitate the harmonization and interconnection of health data have become a requirement for monitoring and preventing illness and also for sharing medical knowledge. Nowadays, cloud-based solutions can support collaborative data science platforms and deliver all types of processing operations through the network service chain. In this article we deal with healthcare-related data management and exchange, and we propose security and privacy requirements together with a novel microservices approach. We investigate how cloud computing can be adopted within healthcare systems. The interoperability of existing technologies will improve the quality of life and the efficiency of healthcare systems by making them more personalized and centered on patients, together with reducing operational costs and medical errors. To have a socially acceptable health network service chain, the security and privacy issues need to be analyzed and addressed. We explore the the security and privacy requirements and implications, and also discuss existing methods, and in the end propose an architecture of a secure manager for cloud-based healthcare-related data management and exchange

Optical-near-IR analysis of globular clusters in the IKN dwarf spheroidal : a complex star formation history

Context. Age, metallicity, and spatial distribution of globular clusters (GCs) provide a powerful tool for reconstructing major starformation episodes in galaxies. IKN is a faint dwarf spheroidal (dSph) in the M 81 group of galaxies. It contains five old GCs, which makes it the galaxy with the highest known specific frequency (S N = 126). Aims. We estimate the photometric age, metallicity, and spatial distribution of the poorly studied IKN GCs. We search SDSS for GC candidates beyond the HST/ACS field of view, which covers half of IKN. Methods. To break the age-metallicity degeneracy in the VI colour, we used WHT/LIRIS KS-band photometry and derived photometric ages and metallicities by comparison with SSP models in the V; I; Ks colour space. Results. IKN GCs’ VIKs colours are consistent with old ages ( 8 Gyr) and a metallicity distribution with a higher mean than is typical for such a dSph ([Fe/H] ' 1:4+0:6 0:2 dex). Their photometric mass range (0:5 < MGC < 4 105 M ) implies an unusually high mass ratio between GCs and field stars, of 10:6%. Mixture model analysis of the RGB field stars’ metallicity suggests that 72% of the stars may have formed together with the GCs. Using the most massive GCSFR relation, we calculated a star formation rate (SFR) of 10 M =yr during its formation epoch. We note that the more massive GCs are closer to the galaxy photometric centre. IKN GCs also appear spatially aligned along a line close to the major axis of the IKN and nearly orthogonal to the plane of spatial distribution of galaxies in the M 81 group. We identify one new IKN GC candidate based on colour and the PSF analysis of the SDSS data Conclusions. The evidence of i) broad and high metallicity distribution of the field IKN RGB stars and its GCs, ii) high fraction, and iii) spatial alignment of IKN GCs supports a scenario for tidally triggered, complex IKN’s star formation history in the context of interactions with galaxies in the M 81 group