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Active regions (ARs) are typical magnetic structures found in the solar atmosphere. We calculate several magnetohydrostatic (MHS) equilibrium models that include the effect of a finite plasma-$\beta$ and gravity and that are representative of these structures in three dimensions. The construction of the models is based on the use of two Euler potentials, $\alpha$ and $\beta$, that represent the magnetic field as ${\bf B}=\nabla \alpha \times \nabla \beta$. The ideal MHS nonlinear partial differential equations are solved numerically using finite elements in a fixed 3D rectangular domain. The boundary conditions are initially chosen to correspond to a potential magnetic field (current-free) with known analytical expressions for the corresponding Euler potentials. The distinctive feature is that we incorporate the effect of shear by progressively deforming the initial potential magnetic field. This procedure is quite generic and allows us to generate a vast variety of MHS models. The thermal structure of the ARs is incorporated through the dependence of gas pressure and temperature on the Euler potentials. Using this method we achieve the characteristic hot and over-dense plasma found in ARs, but we demonstrate that the method can also be applied to study configurations with open magnetic field lines. Furthermore, we investigate basic topologies that include neutral lines. Our focus is on the force balance of the structures and we do not consider the energy balance in the constructed models. In addition, we address the difficult question of the stability of the calculated 3D models. We find that if the plasma is convectively stable, then the system is not prone in general to develop magnetic Rayleigh-Taylor instabilities. Comment: Accepted for publication in A&A

EBEX is a NASA-funded balloon-borne experiment designed to measure the polarization of the cosmic microwave background (CMB). Observations will be made using 1432 transition edge sensor (TES) bolometric detectors read out with frequency multiplexed SQuIDs. EBEX will observe in three frequency bands centered at 150, 250, and 410 GHz, with 768, 384, and 280 detectors in each band, respectively. This broad frequency coverage is designed to provide valuable information about polarized foreground signals from dust. The polarized sky signals will be modulated with an achromatic half wave plate (AHWP) rotating on a superconducting magnetic bearing (SMB) and analyzed with a fixed wire grid polarizer. EBEX will observe a patch covering ~1% of the sky with 8' resolution, allowing for observation of the angular power spectrum from \ell = 20 to 1000. This will allow EBEX to search for both the primordial B-mode signal predicted by inflation and the anticipated lensing B-mode signal. Calculations to predict EBEX constraints on r using expected noise levels show that, for a likelihood centered around zero and with negligible foregrounds, 99% of the area falls below r = 0.035. This value increases by a factor of 1.6 after a process of foreground subtraction. This estimate does not include systematic uncertainties. An engineering flight was launched in June, 2009, from Ft. Sumner, NM, and the long duration science flight in Antarctica is planned for 2011. These proceedings describe the EBEX instrument and the North American engineering flight. 12 pages, 9 figures, Conference proceedings for SPIE Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy V (2010)

Aims. The main purpose of our investigation is to construct the long-time light curve of the PMS star V 1184 Tau. We consider the study of the photometrical variability of PMS stars as very important for understanding stellar evolution. The unusual photometric variability of V 1184 Tau was reported in previous studies as well, but the nature of the observed deep minima is still under discussion. Methods. We present recent data from CCD photometry and from archival photographic plates. The photometric BVRI data presented in this paper were collected from November 2005 to November 2007. To construct the historical light curve of V 1184 Tau, a search for archived photographic observations in the Wide-Field Plate Database (WFPDB) was made. As a result, 412 photographic plates were found containing the field of V 1184 Tau. A part of the plates were scanned at our request and a magnitude estimation was made of V 1184 Tau. Results. Our recent photometric data suggest that the star brightness is still near the minimum. Thus the period of strong light variations that started in 2003 continues up to the present, hence more than 4 years. Our data from the archival photographic plates suggest that an unknown minimum of brightness exists in the approximate period 1980-1985. Taking all available photometric and spectroscopic data into account we must reject the hypothesis that V 1184 Tau is an FU Orionis type object. V 1184 Tau is a G type low-mass star whose spectrum is similar to WTT stars, but its photometric behavior is typical of the UX Orionis variable stars. Assuming the obscuration from orbiting dust clouds as a reason for a deep minimum, we estimate the approximate period of obscurations and the interval between two deep minima. Our calculations give a 25-28 year period between the two minima and approximately 8-10 year duration of the minima.

En este artículo presentamos la investigación que desarrollamos desde hace dos años trabajando con recursos y herramientas tic para enseñar a las personas mayores su uso, funcionalidades y beneficios que les pueden aportar. Consideramos que en la sociedad actual no hemos dado una respuesta satisfactoria a la formación de este colectivo de personas mayores que pensamos que está desfavorecido y lo estamos considerando una necesidad ante los constantes avances y cambios referidos a las tecnologías. Las herramientas que hemos incorporado son la pizarra digital y tabletas para navegación por internet y uso de algunas aplicaciones relacionadas con los dispositivos Android y referidas al dibujo y las mejoras cognitivas; robots básicos para iniciar la programación, la implicación emocional y el pensamiento lógico, y gafas de realidad virtual para acercar la novedad inmersiva en el conocimiento o recuerdo de diferentes entornos. Los buenos resultados obtenidos en este periodo nos animan a continuar y consolidar el proyecto de investigación y definir los modelos didácticos más adecuados y las competencias básicas digitales pertinentes. In this article, we present the research we have been developing for the last two years, working with ict resources and tools to teach older people about its use, functionalities and benefits that can be provided to them. We believe that in today’s society we have not given a satisfactory response to the formation of this group of older people that we think is disadvantaged in terms of the use of ict training and we are considering it a necessity in the face of constant advances and changes related to technologies. The tools we have incorporated are the digital board and tablets for Internet browsing and use of some applications related to Android devices and referred to drawing and cognitive improvements, basic robots to start programming, emotional involvement and logical thinking and glasses of virtual reality to bring the immersive novelty in the knowledge or memory of different environments.The good results obtained in this period encourage us to continue and consolidate the research project and define the most appropriate didactic models and the relevant digital basic competences.

International audience; During sensemaking, people annotate insights: underlining sentences in a document or circling regions on a map. They jot down their hypotheses: drawing correlation lines on scatterplots or creating personal legends to track patterns. We present ActiveInk, a system enabling people to seamlessly transition between exploring data and externalizing their thoughts using pen and touch. ActiveInk enables the natural use of pen for active reading behaviors, while supporting analytic actions by activating any of these ink strokes. Through a qualitative study with eight participants, we contribute observations of active reading behaviors during data exploration and design principles to support sensemaking.

ABSTRA C T We present Doppler images of the young, late-type star PZ Tel from spectroscopic observations at two epochs. The 0.95-d period necessitated dual-site observations in order to obtain full phase coverage. The resulting maximum entropy reconstructions based on leastsquares deconvolved profiles derived from ,2800 photospheric absorption lines reveal the presence of starspots at all latitudes. By cross-correlation of constant-latitude strips from the images, we derive a measure of rotation as a function of latitude. The rate of surface shear is found to be in close agreement with the solar value. Ha absorption transients reveal several prominences to be present at the time of observation. We also examine further evidence for the young evolutionary status of PZ Tel through radial velocity, and lithium abundance.

Medical imaging has evolved from a pure visualization tool to representing a primary source of analytic approaches towards in vivo disease characterization. Hybrid imaging is an integral part of this approach, as it provides complementary visual and quantitative information in the form of morphological and functional insights into the living body. As such, non-invasive imaging modalities no longer provide images only, but data, as stated recently by pioneers in the field. Today, such information, together with other, non-imaging medical data creates highly heterogeneous data sets that underpin the concept of medical big data. While the exponential growth of medical big data challenges their processing, they inherently contain information that benefits a patient-centric personalized healthcare. Novel machine learning approaches combined with high-performance distributed cloud computing technologies help explore medical big data. Such exploration and subsequent generation of knowledge require a profound understanding of the technical challenges. These challenges increase in complexity when employing hybrid, aka dual- or even multi-modality image data as input to big data repositories. This paper provides a general insight into medical big data analysis in light of the use of hybrid imaging information. First, hybrid imaging is introduced (see further contributions to this special Research Topic), also in the context of medical big data, then the technological background of machine learning as well as state-of-the-art distributed cloud computing technologies are presented, followed by the discussion of data preservation and data sharing trends. Joint data exploration endeavours in the context of in vivo radiomics and hybrid imaging will be presented. Standardization challenges of imaging protocol, delineation, feature engineering and machine learning evaluation will be detailed. Last, the paper will provide an outlook into the future role of hybrid imaging in view of personalized medicine, whereby a focus will be given to the derivation of prediction models as part of clinical decision support systems, to which machine learning approaches and hybrid imaging can be anchored.