Joint Europa Mission (JEM): a multi-scale study of Europa to characterize its habitability and search for extant life

Europa is the closest and probably the most promising target to search for extant life in the Solar System, based on complementary evidence that it may fulfil the key criteria for habitability: the Galileo discovery of a sub-surface ocean; the many indications that the ice shell is active and may be partly permeable to transfer of chemical species, biomolecules and elementary forms of life; the identification of candidate thermal and chemical energy sources necessary to drive a metabolic activity near the ocean floor. In this article we are proposing that ESA collaborates with NASA to design and fly jointly an ambitious and exciting planetary mission, which we call the Joint Europa Mission (JEM), to reach two objectives: perform a full characterization of Europa's habitability with the capabilities of a Europa orbiter, and search for bio-signatures in the environment of Europa (surface, subsurface and exosphere) by the combination of an orbiter and a lander. JEM can build on the advanced understanding of this system which the missions preceding JEM will provide: Juno, JUICE and Europa Clipper, and on the Europa lander concept currently designed by NASA (Maize, report to OPAG, 2019). We propose the following overarching goals for our Joint Europa Mission (JEM): Understand Europa as a complex system responding to Jupiter system forcing, characterize the habitability of its potential biosphere, and search for life at its surface and in its sub-surface and exosphere. We address these goals by a combination of five Priority Scientific Objectives, each with focused measurement objectives providing detailed constraints on the science payloads and on the platforms used by the mission. The JEM observation strategy will combine three types of scientific measurement sequences: measurements on a high-latitude, low-altitude Europan orbit; in-situ measurements to be performed at the surface, using a soft lander; and measurements during the final descent to Europa's surface. The implementation of these three observation sequences will rest on the combination of two science platforms: a soft lander to perform all scientific measurements at the surface and sub-surface at a selected landing site, and an orbiter to perform the orbital survey and descent sequences. We describe a science payload for the lander and orbiter that will meet our science objectives. We propose an innovative distribution of roles for NASA and ESA; while NASA would provide an SLS launcher, the lander stack and most of the mission operations, ESA would provide the carrier-orbiter-relay platform and a stand-alone astrobiology module for the characterization of life at Europa's surface: the Astrobiology Wet Laboratory (AWL). Following this approach, JEM will be a major exciting joint venture to the outer Solar System of NASA and ESA, working together toward one of the most exciting scientific endeavours of the 21st century: to search for life beyond our own planet

Reflections on Countertransference and the Holding Environment in Psychodynamic Social Work Practice

The British object relations theorist D.W. Winnicott contributed to psychoanalytic theory and practice through his extensive work in pediatric care. Winnicott emphasized a child’s interaction with the environment, and postulated that “…human infants could not start to be except under certain conditions” (as cited in Buckley, 1986, p. 239). One of these necessary conditions for growth and development is achieved through the activity of holding. Winnicott believed the caretaker’s ability to adapt to the infant and the infant’s physical and psychological needs defined the concept of the “good-enough” parent. The “good-enough” parent is an essential component of the holding environment (St. Clair, 2004, p. 70). The concept of the holding environment also extends to other people and social structures of the child’s life such as the family, the school, and other social systems all contributing to a child’s ability to achieve healthy development (Applegate & Bonovitz, 1995). When the child’s holding environment allows her to express creative gestures without unnecessary impingements, the self naturally evolves (Fonagy& Target, 2003). When this occurs, the child eventually develops a true self, Winnicott’s term for health (Winnicott, 1960). Thus, the conditions of the child’s holding environment highly contribute to the development of her true self. In the following paper, I will use Winnicott’s concepts of the holding environment, countertransference, and true self/false self to explore my psychodynamic social work practice

Comparison between Doppler ultrasonography and multiphase multidetector-row computed tomography in the detection of liver involvement in Rendu-Osler disease: An analysis of 62 patients

International audienc

Endoscopically stapled diverticulostomy for Zenker's diverticulum: results of a multidisciplinary team approach

Abstract Background A variety of open and endoscopic surgical approaches for the treatment of Zenker's diverticulum have been described. In recent years, growing evidence has shown that the endoscopic techniques are superior to the open approaches in many aspects. Among the endoscopic techniques, endoscopically stapled diverticulostomy (ESD) appears to have better efficacy and safety than the other endoscopic techniques. Methods This study retrospectively reviewed the medical records of all the patients with Zenker's diverticulum treated surgically by the same team, which involved an ear, nose, and throat surgeon and an endoscopic surgeon. Results From January 2002 to March 2008, 55 consecutive patients with Zenker's diverticulum underwent 60 ESDs. The mean follow-up time was 32.6 months (range, 1-72 months). The mean operative time was 21.8 min (range, 5-45 min), and the average hospital stay was 2.24 days (range, 1-30 days). The treatment was technically feasible for 51 patients (93%), and initial symptom relief without recurrence was achieved for 46 patients (90.2%) after a single procedure. Five patients with recurrent symptoms underwent a successful revision ESD, with a 100% success rate among the patients for whom the procedure was technically feasible. Only two major postoperative complications (3.64%) occurred: one esophageal perforation and pneumomediastinum and one severe esophageal edema. Both patients had complete resolution of their complications with conservative treatment and no long-term sequela. Conclusion The findings showed endoscopic stapled diverticulostomy to be both safe and effective. Compared with the historical results of open diverticulectomy and myotomy, the reported procedure has fewer complications and better outcomes and should become the procedure of choice for the treatment of most patients with a diagnosis of Zenker's diverticulum

Nucleation, Growth Mechanism, and Controlled Coating of ZnO ALD onto Vertically Aligned N-Doped CNTs

Zinc oxide thin films were deposited on vertically aligned nitrogen-doped carbon nanotubes (N-CNTs) by atomic layer deposition (ALD) from diethylzinc and water. The study demonstrates that doping CNTs with nitrogen is an effective approach for the \"activation\" of the CNTs surface for the ALD of metal oxides. Conformal ZnO coatings are already obtained after 50 ALD cycles, whereas at lower ALD cycles an island growth mode is observed. Moreover, the process allows for a uniform growth from the top to the bottom of the vertically aligned N-CNT arrays. X-ray photoelectron spectroscopy demonstrates that ZnO nucleation takes place at the N-containing species on the surface of the CNTs by the formation of the Zn-N bonds at the interface between the CNTs and the ZnO film

PERSPECTIVES ON SOCIAL WORK VOLUME 6 (FALL 2007)

This is the full-text volume of Perspectives on Social Work, vol. 6 (Fall 2007

[Acute heart disease in search and rescue helicopter missions, from French Navy. A retrospective study from 2000 to 2007].

International audienceBACKGROUND: Search and rescue helicopters from the French navy conduct ambulance and search and rescue missions near the western coast of the French Britain. The team on board includes military doctor and paramedic. Operations in this area are challenging due to long distances and severe weather conditions. METHODS: We studied retrospectively 205 search and rescue missions from 2000 to 2007 with special emphasis on acute heart disease and operative conditions. RESULTS: 12.2% of the missions (25/205) concern acute heart disease dominated by myocardial infarction elevation myocardial infarction. All of the patients are male. Most of them are seafarers and the others come from ferries with a median age of 53.4 years. Sixty-two percent of the missions were carried in darkness. The median range is about 80 nautical miles. Two patients died during search and rescue missions. All patient are hospitalized. CONCLUSION: Ambulance and search and rescue mission near the western coasting of the French Britain are a challenge. Using a heavy helicopter from French Navy was the best way to carry medical treatment to seafarers and passengers of ferries suffering from acute heart disease