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Purpose: Retinal prostheses are susceptible to damage by body fluids over time. Long-term reliability of retinal prostheses requires hermetic packaging to protect the electronic circuitry of the implant from the harsh environment of the human body and a robust high-density electrode array for safe chronic[for full text, please go to the a.m. URL], Artificial Vision 2013

Purpose: To investigate whether Argus II subjects can locate human faces with their systems using a facial detection algorithm and whether detection speed improves when field of view that is mapped onto the Argus II implant is changed (i.e. demagnified). Methods: To date, more than 50 patients [for full text, please go to the a.m. URL], Artificial Vision 2013

Purpose: The purpose of this work was to develop an instructional curriculum for Argus® II Retinal Prosthesis System (Argus II) patients who have undergone successful implantation of the system in a commercial setting. In the clinical trial that supported approval of Argus II for commercial use[for full text, please go to the a.m. URL], Artificial Vision 2013

Purpose: The Argus II clinical trial is the largest trial of a retinal prosthesis in the world. Its subjects are constantly followed for safety and performance. There are 10 implanting centers involved in the clinical trial in the US, UK, France, and Switzerland. Before implantation, all 30 subjects[for full text, please go to the a.m. URL], 27. Internationaler Kongress der Deutschen Ophthalmochirurgen

International audience; Planet-planet scattering has been suggested as a mechanism to explain the disproportionate number of planet-planet pairs found to lie on or near an apsidal separatrix, in which one planet's eccentricity periodically drops to near-zero. We present the results of numerical simulations of 2-planet systems having arisen from dynamically unstable 3-planet systems. We show that the distribution of near-separatrix systems arising after an instability is consistent with the observed systems, further strengthening the planet-planet scattering hypothesis. We also note that many observed systems have been found near their extreme eccentricity values. Such a pattern may suggest a bias in exoplanet observations, as planets should have an equal probability of being discovered at any point in their secular cycle. We test this possibility by numerically integrating known multiplanet systems and determining the relative time each planet spends in a given eccentricity range and then comparing this distribution of eccentricity values to the observational uncertainty. We find that planets tend to spend more time near their minimum and maximum values as they represent turning points in the oscillations. Moreover, the uncertainties for many eccentricities are so large that we cannot make strong statements regarding the possibility that planets are being discovered at their extreme eccentricities too often. However, as uncertainties become smaller and more multiplanet systems are discovered, this potential bias should be revisited.

International audience; Terrestrial planets in the classic "habitable zone" (Kasting et al. 1993) of stars may be influenced by tides. Tidal evolution is poorly constrained and multiple acceptable models exist which, although qualitatively similar, predict different rates of evolution. Using different models, we examine how tides may modify several key properties of planets in the habitable zone: semi-major axis, eccentricity, obliquity and rotation rate. Tides can lock the rotation rate and erode the obliquity (to 0 or 180 degrees) in 103-1010 years, depending on the stellar mass and eccentricity. Some tidal models even predict significant obliquity evolution for planets in the habitable zones of solar-mass stars. This evolution dissipates energy in the planet's interior (at the expense of the orbit) and leads to "tidal heating." In extreme cases of high eccentricity and very low mass stars, the heating may initiate a runaway greenhouse, and/or total evaporation of potential surface water, eliminating any hope of habitability. After the spin properties have equilibrated, the planet is said to be "tidally locked" and further evolution primarily changes the orbital angular momentum. For exoplanets, tides tend to reduce eccentricities and semi-major axes, and can also change the rotation period, eventually reaching synchroneity with the orbit when both eccentricity and obliquity reach zero. Orbital circularization requires millions to trillions of years, depending on the planet's initial conditions and the tidal model assumed. Tidal heating also occurs during circularization and planets may pass through a "super-Io" phase prior to reaching internal heating rates similar to the modern day Earth. Tides clearly have the potential to impact habitability and may lead to planets with evolutionary paths markedly different from the Earth. These issues are presented and discussed for the simple case of one planet orbiting one star.

The purpose of this study is to examine the results of repeat lumbar puncture in infants with initial positive cerebrospinal fluid (CSF) cultures in order to determine the clinical characteristics and outcomes of infants with repeat positive cultures.

The recently discovered planet CoRoT-7 b has a density (5.7 g/cc) consistent with a rocky composition (Leger et al. 2009; Queloz et al. 2009). However, CoRoT-7 b's semi-major axis (0.0172 AU) suggests the planet has a history unlike the planets in our solar system. The strong stellar insolation received by CoRoT-7 b can quickly drive off an atmosphere and may have evaporated a few Earth masses of rocky material during the planet's lifetime. Such rapid mass loss even suggests that CoRoT-7 b may be the remnant core of a hot Jupiter whose gaseous envelope was completely evaporated. Also important are tides, which have drawn the planet in from a more distant, and possibly eccentric, orbit. As the planet neared its host star, the rate of mass loss probably increased dramatically, but mass loss slows tidal migration, resulting in a complex interplay between tides and mass loss. We combine tidal evolution and mass loss models to constrain the range of original orbits and masses of CoRoT-7 b and find, indeed, that CoRoT-7 b may once have been a gas giant planet. We discuss the plausible evolutionary pathways that allow CoRoT-7 b to have begun life as a gas giant. Our results suggest that similar processes may have influenced many other close-in exoplanets as well. Studying the coupled processes of mass loss and tidal migration may thus be crucial to unraveling the origins of the hundreds of hot super-Earths that may soon be discovered by the Kepler and CoRoT missions.

Context. 2MASS J05352184−0546085 (2M0535−05) is the only known eclipsing brown dwarf (BD) binary, and so may serve as a benchmark for models of BD formation and evolution. However, theoretical predictions of the system’s properties seem inconsistent with observations: i) the more massive (primary) component is observed to be cooler than the less massive (secondary) one; ii) the secondary is more luminous (by ≈1024 W) than expected. Previous explanations for the temperature reversal have invoked reduced convective efficiency in the structure of the primary, connected to magnetic activity and to surface spots, but these explanations cannot account for the enhanced luminosity of the secondary. Previous studies also considered the possibility that the secondary is younger than the primary. Aims. We study the impact of tidal heating to the energy budget of both components to determine if it can account for the observed temperature reversal and the high luminosity of the secondary. We also compare various plausible tidal models to determine a range of predicted properties. Methods. We apply two versions of two different, well-known models for tidal interaction, respectively: i) the “constant-phase-lag” model; and ii) the “constant-time-lag” model and incorporate the predicted tidal heating into a model of BD structure. The four models differ in their assumptions about the rotational behavior of the bodies, the system’s eccentricity and putative misalignments ψ between the bodies’ equatorial planes and the orbital plane of the system. Results. The contribution of heat from tides in 2M0535−05 alone may only be large enough to account for the discrepancies between observation and theory in an unlikely region of the parameter space. The tidal quality factor QBD of BDs would have to be 103.5 and the secondary needs a spin-orbit misalignment of 50◦. However, tidal synchronization time scales for 2M0535−05 restrict the tidal dissipation function to log(QBD) 4.5 and rule out intense tidal heating in 2M0535−05. We provide the first constraint on Q for BDs. Conclusions. Tidal heating alone is unlikely to be responsible for the surprising temperature reversal within 2M0535−05. But an evolutionary embedment of tidal effects and a coupled treatment with the structural evolution of the BDs is necessary to corroborate or refute this result. The heating could have slowed down the BDs’ shrinking and cooling processes after the birth of the system ≈1 Myr ago, leading to a feedback between tidal inflation and tidal heating. Observations of old BD binaries and measurements of the Rossiter-McLaughlin effect for 2M0535−05 can provide further constraints on QBD. peerReviewed

A 62-year-old man with a history of non-insulin-dependent diabetes mellitus, hypertension and obesity, presented for elective lumbar laminectomy for spinal canal stenosis. Twenty minutes after placement in the prone position, he developed left orbital proptosis. The surgery was deferred and a subsequent CT scan showed an orbital haemangioma. This case highlights the importance of meticulous attention to eye-care for patients in the prone position.