Constraints on the depth and geometry of the magma chamber of the Olympus Mons Volcano, Mars

The summit caldera of the Olympus Mons volcano exhibits one of the clearest examples of tectonic processes associated with shield volcanism on Mars. The radial distance from the center of the transition from concentric ridges to concentric graben within the oldest crater provides a constraint on the geometry and depth of the subsurface magmatic reservoir at the time of subsidence. Here, researchers use this constraint to investigate the size, shape, and depth of the reservoir. Their approach consists of calculating radial surface stresses corresponding to the range of subsurface pressure distributions representing an evacuating magma chamber. They then compare stress patterns to the observed radial positions of concentric ridges and graben. The problem is solved by employing the finite element approach using the program TECTON

Libros electrónicos en la Red de Bibliotecas del CSIC. Creación de una colección común

[EN] The collection of digital resources of the CSIC Library Network has been developed mainly for electronic journals. However in the last three years its model for acquisition, management and accessibility applied to journals has been tried to ebooks. The first phase of the introduction of electronic books in the CSIC did not follow a defined strategy. Since 2007 a plan of cooperation has been established within the network in order to create a common collection of quality electronic books. In this article we describe the experience of cooperative purchasing among libraries in the network, the selected collections, how to make them accessible to library patrons, their usage up to now, the investments made and future plans to consolidate the CSIC ebooks collection.[ES] La colección de recursos digitales de la Red de Bibliotecas del CSIC ha estado formada fundamentalmente por revistas electrónicas. Pero en los últimos 3 años el modelo de adquisición, gestión y accesibilidad aplicado a las revistas se ha exportado a los libros electrónicos. La primera fase de la introducción de libros electrónicos en el CSIC no siguió una estrategia definida. Desde 2007 se ha establecido un plan de cooperación dentro de la propia Red que persigue crear una colección común de libros electrónicos de calidad. Se presenta la experiencia de compras cooperativas entre las bibliotecas de la Red, las colecciones seleccionadas, cómo se hacen accesibles a los usuarios, el uso que han tenido, las inversiones realizadas y los planes futuros de consolidación de los libros electrónicos en el CSIC.Peer reviewe

Evolution of the Olympus Mons Caldera, Mars

Extensive high-resolution (15 to 20 m/pixel) coverage of Olympus Mons volcano permits the investigation of the sequence of events associated with the evolution of the nested summit caldera. The sequence of the intra-caldera events is well illustrated by image data collected on orbits 473S and 474S of Viking Orbiter 1. These data cover both the oldest and youngest portions of the caldera floor. The chronology inferred from the observations is presented which in turn can be interpreted in terms of the internal structure of the volcano (i.e., magma chamber depth and the existence of dikes)

Small-molecule inhibition of BRD4 as a new potent approach to eliminate leukemic stem- and progenitor cells in acute myeloid leukemia (AML)

Acute myeloid leukemia (AML) is a life-threatening stem cell disease characterized by uncontrolled proliferation and accumulation of myeloblasts. Using an advanced RNAi screen-approach in an AML mouse model we have recently identified the epigenetic ‘reader’ BRD4 as a promising target in AML. In the current study, we asked whether inhibition of BRD4 by a small-molecule inhibitor, JQ1, leads to growth-inhibition and apoptosis in primary human AML stem- and progenitor cells. Primary cell samples were obtained from 37 patients with freshly diagnosed AML (n=23) or refractory AML (n=14). BRD4 was found to be expressed at the mRNA and protein level in unfractionated AML cells as well as in highly enriched CD34+/CD38− and CD34+/CD38+ stem- and progenitor cells in all patients examined. In unfractionated leukemic cells, submicromolar concentrations of JQ1 induced major growth-inhibitory effects (IC50 0.05-0.5 μM) in most samples, including cells derived from relapsed or refractory patients. In addition, JQ1 was found to induce apoptosis in CD34+/CD38− and CD34+/CD38+ stem- and progenitor cells in all donors examined as evidenced by combined surface/Annexin-V staining. Moreover, we were able to show that JQ1 synergizes with ARA-C in inducing growth inhibition in AML cells. Together, the BRD4-targeting drug JQ1 exerts major anti-leukemic effects in a broad range of human AML subtypes, including relapsed and refractory patients and all relevant stem- and progenitor cell compartments, including CD34+/CD38− and CD34+/CD38+ AML cells. These results characterize BRD4-inhibition as a promising new therapeutic approach in AML which should be further investigated in clinical trials

An investigation of the color reproduction accuracy of two halftoning algorithms for dot matrix systems

The recent popularity of dot matrix printing technologies has renewed interest in developing color halftoning techniques for these systems. A color reproduction scheme based on colorimetric principles would provide accurate color rendition, and can be configured to different hardware implementations. Additionally, where there are demands for multiple copies, color reproduction accuracy is assured to the nth generation. A binary dot matrix halftoning algorithm previously used for black-and-white reproduction (error diffusion) and a new algorithm to be described (EZ method) were investigated in terms of their color reproduction capabilities, with the objective to achieve colorimetric color reproduction. The error diffusion technique made poor system color selections when used in XYZ tristimulus space. As a result, large hue, saturation, and ΔE*ab errors were experienced. The EZ Color Algorithm provided better color accuracy, with an average color difference of less than three for a 4x4 cell size. A uniform color space, such as CIELAB, is considered a minimum requirement in order for the error diffusion algorithm to provide colorimetric color reproduction. Hue, saturation, and ΔE*ab errors were minimized when this color space was used. The EZ Color Algorithm provides several important features including the incorporation of the black colorant explicity in the color formulation, selection of system colors prior to quantizing, and quantization of system color areas instead of reflectance values

Cardiovascular magnetic resonance imaging for diagnosis and clinical management of suspected cardiac masses and tumours

Aims To evaluate the diagnostic accuracy of cardiovascular magnetic resonance (CMR) imaging from a risk-stratification and therapeutic-management perspective in patients with suspected cardiac tumours. Methods and results Cardiovascular magnetic resonance exams of 41 consecutive patients (aged 61 ± 14 years, 21 men) referred for evaluation of a suspected cardiac mass were reviewed for tumour morphology and signal characteristics in various unenhanced and contrast-enhanced sequences. Cardiovascular magnetic resonance-derived diagnosis and treatment were compared with clinical outcome and histology in patients undergoing surgery or autopsy (n = 20). In 18 of 41 patients, CMR excluded masses or reclassified them as normal variants; all were treated conservatively. In 23 of 41 patients, CMR diagnosed a neoplasm (14 ‘benign', 8 ‘malignant', and 1 'equivocal'); 18 of these patients were operated on, 2 managed conservatively, and 3 by palliation. During follow-up of 705 (inter-quartile range 303-1472) days, 13 patients died. No tumour-related deaths occurred in conservatively managed patients. Patients with a CMR-based diagnosis and treatment of benign tumour had a similar survival as patients without detectable tumour. Compared with histology, CMR correctly classified masses as ‘benign or malignant' in 95% of the cases. Tumour perfusion, invasiveness, localization, and pericardial fluid were valuable to distinguish between malignant and benign tumours. Soft tissue contrast and signal intensity patterns in various sequences were valuable for excluding neoplastic lesions and helped to obtain tissue characterization at the histological level in selected tumour cases, respectively. Conclusion Comprehensive CMR provides a confident risk-stratification and clinical-management tool in patients with suspected tumours. Patients where CMR excludes tumours can be managed conservativel

Factors affecting the bacterial community composition and heterotrophic production of Columbia River estuarine turbidity maxima

© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in MicrobiologyOpen 6 (2017): e00522, doi:10.1002/mbo3.522.Estuarine turbidity maxima (ETM) function as hotspots of microbial activity and diversity in estuaries, yet, little is known about the temporal and spatial variability in ETM bacterial community composition. To determine which environmental factors affect ETM bacterial populations in the Columbia River estuary, we analyzed ETM bacterial community composition (Sanger sequencing and amplicon pyrosequencing of 16S rRNA gene) and bulk heterotrophic production (3H-leucine incorporation rates). We collected water 20 times to cover five ETM events and obtained 42 samples characterized by different salinities, turbidities, seasons, coastal regimes (upwelling vs. downwelling), locations, and particle size. Spring and summer populations were distinct. All May samples had similar bacterial community composition despite having different salinities (1–24 PSU), but summer non-ETM bacteria separated into marine, freshwater, and brackish assemblages. Summer ETM bacterial communities varied depending on coastal upwelling or downwelling conditions and on the sampling site location with respect to tidal intrusion during the previous neap tide. In contrast to ETM, whole (>0.2 μm) and free-living (0.2–3 μm) assemblages of non-ETM waters were similar to each other, indicating that particle-attached (>3 μm) non-ETM bacteria do not develop a distinct community. Brackish water type (ETM or non-ETM) is thus a major factor affecting particle-attached bacterial communities. Heterotrophic production was higher in particle-attached than free-living fractions in all brackish waters collected throughout the water column during the rise to decline of turbidity through an ETM event (i.e., ETM-impacted waters). However, free-living communities showed higher productivity prior to or after an ETM event (i.e., non-ETM-impacted waters). This study has thus found that Columbia River ETM bacterial communities vary based on seasons, salinity, sampling location, and particle size, with the existence of three particle types characterized by different bacterial communities in ETM, ETM-impacted, and non-ETM-impacted brackish waters. Taxonomic analysis suggests that ETM key biological function is to remineralize organic matter.National Science Foundation Grant Number: OCE-042460

MESSENGER at Mercury: Early Orbital Operations

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 under NASA's Discovery Program, was inserted into orbit about the planet Mercury in March 2011. MESSENGER's three flybys of Mercury in 2008-2009 marked the first spacecraft visits to the innermost planet since the Mariner 10 flybys in 1974-1975. The unprecedented orbital operations are yielding new insights into the nature and evolution of Mercury. The scientific questions that frame the MESSENGER mission led to the mission measurement objectives to be achieved by the seven payload instruments and the radio science experiment. Interweaving the full set of required orbital observations in a manner that maximizes the opportunity to satisfy all mission objectives and yet meet stringent spacecraft pointing and thermal constraints was a complex optimization problem that was solved with a software tool that simulates science observations and tracks progress toward meeting each objective. The final orbital observation plan, the outcome of that optimization process, meets all mission objectives. MESSENGER's Mercury Dual Imaging System is acquiring a global monochromatic image mosaic at better than 90% coverage and at least 250 m average resolution, a global color image mosaic at better than 90% coverage and at least 1 km average resolution, and global stereo imaging at better than 80% coverage and at least 250 m average resolution. Higher-resolution images are also being acquired of targeted areas. The elemental remote sensing instruments, including the Gamma-Ray and Neutron Spectrometer and the X-Ray Spectrometer, are being operated nearly continuously and will establish the average surface abundances of most major elements. The Visible and Infrared Spectrograph channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer is acquiring a global map of spectral reflectance from 300 to 1450 nm wavelength at a range of incidence and emission angles. Targeted areas have been selected for spectral coverage into the ultraviolet with the Ultraviolet and Visible Spectrometer (UVVS). MESSENGER's Mercury Laser Altimeter is acquiring topographic profiles when the slant range to Mercury's surface is less than 1800 km, encompassing latitudes from 20 deg. S to the north pole. Topography over the remainder of the southern hemisphere will be derived from stereo imaging, radio occultations, and limb profiles. MESSENGER's radio science experiment is determining Mercury's gravity field from Doppler signals acquired during frequent downlinks. MESSENGER's Magnetometer is measuring the vector magnetic field both within Mercury's magnetosphere and in Mercury's solar wind environment at an instrument sampling rate of up to 20 samples/s. The UVVS is determining the three-dimensional, time-dependent distribution of Mercury's exospheric neutral and ionic species via their emission lines. During each spacecraft orbit, the Energetic Particle Spectrometer measures energetic electrons and ions, and the Fast Imaging Plasma Spectrometer measures the energies and mass per charge of thermal plasma components, both within Mercury's magnetosphere and in Mercury's solar-wind environment. The primary mission observation sequence will continue for one Earth year, until March 2012. An extended mission, currently under discussion with NASA, would add a second year of orbital observations targeting a set of focused follow-on questions that build on observations to date and take advantage of the more active Sun expected during 2012-2013. MESSENGER's total primary mission cost, projected at $446 M in real-year dollars, is comparable to that of Mariner 10 after adjustment for inflation

Agenda-Setting in der Blogosphäre? Eine empirische Überprüfung

Auf der Makroebene der Blogosphäre gibt es die sogenannten „A-Blogger“. Diese zeichnen sich dadurch aus, dass ihr Weblog (Blog) im Gegensatz zur großen Mehrheit der Blogs über sehr viele Inlinks-verfügt. In der Literatur sind verschiedene theoretische Ansätze zu finden, die sich mit der Frage beschäftigen, welche Funktion den A-Bloggern in der Blogosphäre zukommt. So wird beispielsweise davon gesprochen, dass sie eine Agenda-Setting-Funktion für die Blogosphäre einnehmen. Das bedeutet, dass sie die in der Blogosphäre diskutierten Themen vorgeben und somit die anderen Blogs, die über deutlich weniger Links verfügen, in deren Themenwahl beeinflussen. Anhand eines Datensatzes (Burton, Java et al. 2009) soll überprüft werden, ob eine Agenda-Setting-Funktion der deutschen A-Blogger für die deutschsprachige Blogosphäre bestätigt werden kann. Als Methode wird die Hyperlinkanalyse eingesetzt