GAUSS - genesis of asteroids and evolution of the solar system: A sample return mission to Ceres.

The goal of Project GAUSS (Genesis of Asteroids and evolUtion of the Solar System) is to return samples from the dwarf planet Ceres. Ceres is the most accessible candidate of ocean worlds and the largest reservoir of water in the inner Solar System. It shows active volcanism and hydrothermal activities in recent history. Recent evidence for the existence of a subsurface ocean on Ceres and the complex geochemistry suggest past habitability and even the potential for ongoing habitability. GAUSS will return samples from Ceres with the aim of answering the following top-level scientific questions: What is the origin of Ceres and what does this imply for the origin of water and other volatiles in the inner Solar System?What are the physical properties and internal structure of Ceres? What do they tell us about the evolutionary and aqueous alteration history of dwarf planets?What are the astrobiological implications of Ceres? Is it still habitable today?What are the mineralogical connections between Ceres and our current collections of carbonaceous meteorites?

Retinopatía necrosante herpética en trasplantado renal con mofetil micofenolato / Necrotizing herpetic retinopathy in kidney-transplanted patients on mycophenolate mofetil

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In vitro evaluation of the antielastase activity of polycyclic ß-lactams.

A series of bi- and tricyclic ß-lactam compounds was synthesized and evaluated as inhibitors of cleavage of synthetic substrates in vitro by the serine proteases Human Leukocyte Elastase (HLE), Human Leukocyte Proteinase 3 (HLPR3) and Porcine Pancreatic Elastase (PPE). The obtained results have permitted us to describe a homobenzocarbacephem compound as HLE and HLPR3 inhibitor, to observe the positive effect that the styryl group exerts on the HLE inhibitory activity in polycyclic ß-lactam compounds and to conclude that the hydroxyl function decreases the HLE inhibitory activity or rules it out completely.

ESSC-ESF position paper--science-driven scenario for space exploration: report from the European Space Sciences Committee (ESSC).

In 2005 the then ESA Directorate for Human Spaceflight, Microgravity and Exploration (D-HME) commissioned a study from the European Science Foundation's (ESF) European Space Sciences Committee (ESSC) to examine the science aspects of the Aurora Programme in preparation for the December 2005 Ministerial Conference of ESA Member States, held in Berlin. A first interim report was presented to ESA at the second stakeholders meeting on 30 and 31 May 2005. A second draft report was made available at the time of the final science stakeholders meeting on 16 September 2005 in order for ESA to use its recommendations to prepare the Executive proposal to the Ministerial Conference. The final ESSC report on that activity came a few months after the Ministerial Conference (June 2006) and attempted to capture some elements of the new situation after Berlin, and in the context of the reduction in NASA's budget that was taking place at that time; e.g., the postponement sine die of the Mars Sample Return mission. At the time of this study, ESSC made it clear to ESA that the timeline imposed prior to the Berlin Conference had not allowed for a proper consultation of the relevant science community and that this should be corrected in the near future. In response to that recommendation, ESSC was asked again in the summer of 2006 to initiate a broad consultation to define a science-driven scenario for the Aurora Programme. This exercise ran between October 2006 and May 2007. ESA provided the funding for staff support, publication costs, and costs related to meetings of a Steering Group, two meetings of a larger ad hoc group (7 and 8 December 2006 and 8 February 2007), and a final scientific workshop on 15 and 16 May 2007 in Athens. As a result of these meetings a draft report was produced and examined by the Ad Hoc Group. Following their endorsement of the report and its approval by the plenary meeting of the ESSC, the draft report was externally refereed, as is now normal practice with all ESSC-ESF reports, and amended accordingly. The Ad Hoc Group defined overarching scientific goals for Europe's exploration programme, dubbed "Emergence and co-evolution of life with its planetary environments," focusing on those targets that can ultimately be reached by humans, i.e., Mars, the Moon, and Near Earth Objects. Mars was further recognized as the focus of that programme, with Mars sample return as the recognized primary goal; furthermore the report clearly states that Europe should position itself as a major actor in defining and leading Mars sample return missions. The report is reproduced in this article. On 26 November 2008 the Ministers of ESA Member States decided to give a high strategic priority to the robotic exploration programme of Mars by funding the enhanced ExoMars mission component, in line therefore with the recommendations from this ESSC-ESF report.

Lesión lítica en la tibia en un paciente procedente de Ecuador / Lytic lesion in the tibia in a patient from Ecuador

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A soft solid surface on Titan as revealed by the Huygens Surface Science Package.

The surface of Saturn's largest satellite--Titan--is largely obscured by an optically thick atmospheric haze, and so its nature has been the subject of considerable speculation and discussion. The Huygens probe entered Titan's atmosphere on 14 January 2005 and descended to the surface using a parachute system. Here we report measurements made just above and on the surface of Titan by the Huygens Surface Science Package. Acoustic sounding over the last 90 m above the surface reveals a relatively smooth, but not completely flat, surface surrounding the landing site. Penetrometry and accelerometry measurements during the probe impact event reveal that the surface was neither hard (like solid ice) nor very compressible (like a blanket of fluffy aerosol); rather, the Huygens probe landed on a relatively soft solid surface whose properties are analogous to wet clay, lightly packed snow and wet or dry sand. The probe settled gradually by a few millimetres after landing.

Complete medial dislocation of the first cuneiform: a case report.

Isolated dislocation of the first cuneiform bone is an extremely rare lesion that can usually be diagnosed on plain radiography. Few cases of this injury have been previously described in the literature. The case presented here resulted from a torsion injury and was treated by means of closed reduction with the aid of pointed reduction forceps. After fixation with Kirschner wires, the foot was immobilized for 6 weeks. The patient recovered uneventfully and remains asymptomatic 3 years later.

Intradural disc herniation and epidural gas: something more than a casual association?

STUDY DESIGN: The case of a patient with an intradural disc herniation associated with gas in the spinal canal is presented. OBJECTIVE: To alert spine surgeons to this potential association. SUMMARY OF BACKGROUND DATA: This association was described previously in five patients, a fact that seems surprising given the relative rarity of both intraspinal gas and intradural herniations. METHODS: The case is presented of a female patient with lumbosciatic pain who developed an incomplete cauda equina syndrome. An asymmetric discopathy of the L2-L3 space and a gas bubble with disc material within the spinal canal was noticed in the radiologic explorations. The literature and the authors' experience are reviewed with the aim of confirming the frequency of intradural herniation in association with gas in the spinal canal. RESULTS: A laminoarthrectomy of the involved space was performed followed by direct intradural examination, which revealed a disc fragment that was excised. An instrumented L2-L3 arthrodesis was performed. Postoperative evolution was satisfactory. To date, the authors have found this association in 2% of the patients with intraspinal gas. CONCLUSION: The potential presence of an intradural disc herniation must always be considered when performing an open discectomy on a patient whose CT scan study shows the presence of epidural gas. This association is particularly striking given the relative rarity of intradural herniations and intraspinal gas. In the event that no clear disc herniation was found, an intradural examination may be indicated to justify clinical signs and symptoms or previous radiologic studies.

L5 root compression resulting from an L2-L3 disc herniation.

We present the rare case of a patient affected by low back pain and bilateral L5 sciatica from an L2-L3 herniation. Only 2 cases of monoradicular L5 compression in the high lumbar spine have been reported. The initial computed tomography study of the L4-L5 and L5-S1 spaces revealed no significant alterations. Magnetic resonance imaging showed a disc herniation at L2-3. The electrophysiological study confirmed clinical suspicions of L5 root involvement. A bilateral laminotomy with discectomy on both sides of the L2-3 space was performed. Pain disappeared completely after surgery. The patient remains asymptomatic 2 years after the operation.

Stereospecific synthesis of polyfunctionalized carbacephams induced by titanocene(III) chloride.

Enantiomerically pure N-substituted epoxyalkene-2-azetidinones reacted with titanocene monochloride to give stereospecifically polyfunctionalized bicyclic beta-lactams. Four isomeric epoxyaldehydes 2 reacted with TiCp2Cl to give exclusively the respective carbacephams 7 while under the same reaction conditions the epoxyesters 1, which are more hindered for an intramolecular addition, gave the cyclization products 6 (only two isomers) and/or the elimination products 5 (all isomers).

Stereospecific synthesis of highly functionalized tricyclic beta-lactams by radical cyclizations using titanocene monochloride.

The reductive opening of epoxyimonobactams 1 with titanoncene (III) chloride gives rise to radicals that can be trapped by intramolecular pi systems (i.e., conjugated alkenes and lactone and amide carbonyls) in a stereospecific way to give new carbocyclic compounds such as tribactam 2.