275 research outputs found
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Marco Polo: near Earth object sample return mission
Marco Polo is a joint European-Japanese mission of sample return from a Near Earth Object. The Marco Polo proposal was submitted to ESA on July 2007 in the framework of the Cosmic Vision 2015-2025 context, and on October 2007 passed the first evaluation process. The primary objectives of this mission is to visit a primitive NEO, belonging to a class that cannot be related to known meteorite types, to characterize it at multiple scales, and to bring samples back to Earth. Marco Polo will give us the first opportunity for detailed laboratory study of the most primitive materials that formed the planets. This will allow us to improve our knowledge on the processes which governed the origin and early evolution of the Solar System, and possibly of the life on Earth
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Marco Polo: A near Earth object sample return mission
From Introduction:
MARCO POLO is a joint European-Japanese sample return mission to a Near-Earth Object. In late 2007 this mission was selected by ESA, in the framework of COSMIC VISION 2015-2025, for an assessment scheduled to last until mid 2009.
This Euro-Asian mission will go to a primitive Near-Earth Object (NEO), such as a C or D type asteroid. The spacecraft will rendezvous with the object, and over an extended period scientifically characterize it at multiple scales and bring samples back to Earth for detailed scientific investigation
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Overview of the results of the organics PET Study of the cometary samples returned from comet Wild 2 by the Stardust mission
This presenation will provide an overview of the efforts and results produced by the Organics Preliminary Examination Team during their studies of the samples returned from comet Wild 2 by the Stardust spacecraft
The USNO-B Catalog
USNO-B is an all-sky catalog that presents positions, proper motions,
magnitudes in various optical passbands, and star/galaxy estimators for
1,042,618,261 objects derived from 3,643,201,733 separate observations. The
data were obtained from scans of 7,435 Schmidt plates taken for the various sky
surveys during the last 50 years. USNO-B1.0 is believed to provide all-sky
coverage, completeness down to V = 21, 0.2 arcsecond astrometric accuracy at
J2000, 0.3 magnitude photometric accuracy in up to five colors, and 85%
accuracy for distinguishing stars from non-stellar objects. A brief discussion
of various issues is given here, but the actual data are available from
http://www.nofs.navy.mil and other sites.Comment: Accepted by Astronomical Journa
Supermassive Black Holes in Galactic Nuclei: Past, Present and Future Research
This review discusses the current status of supermassive black hole research,
as seen from a purely observational standpoint. Since the early '90s, rapid
technological advances, most notably the launch of the Hubble Space Telescope,
the commissioning of the VLBA and improvements in near-infrared speckle imaging
techniques, have not only given us incontrovertible proof of the existence of
supermassive black holes, but have unveiled fundamental connections between the
mass of the central singularity and the global properties of the host galaxy.
It is thanks to these observations that we are now, for the first time, in a
position to understand the origin, evolution and cosmic relevance of these
fascinating objects.Comment: Invited Review, 114 pages. Because of space requirements, this
version contains low resolution figures. The full resolution version can be
downloaded from http://www.physics.rutgers.edu/~lff/publications.htm
Genes flow by the channels of culture: the genetic imprint of matrilocality in Ngazidja, Comoros Islands
International audienc
Dust Processing in Disks around T Tauri Stars
The 8-14 micron emission spectra of 12 T Tauri stars in the Taurus/Auriga
dark clouds and in the TW Hydrae association obtained with the Infrared
Spectrograph (IRS; The IRS is a collaborative venture between Cornell
University and Ball Aerospace Corporation funded by NASA through the Jet
Propulsion Laboratory and the Ames Research Center.) on board Spitzer are
analyzed. Assuming the 10 micron features originate from silicate grains in the
optically thin surface layers of T Tauri disks, the 8-14 micron dust emissivity
for each object is derived from its Spitzer spectrum. The emissivities are fit
with the opacities of laboratory analogs of cosmic dust. The fits include small
nonspherical grains of amorphous silicates (pyroxene and olivine), crystalline
silicates (forsterite and pyroxene), and quartz, together with large fluffy
amorphous silicate grains. A wide range in the fraction of crystalline silicate
grains as well as large silicate grains among these stars are found. The dust
in the transitional-disk objects CoKu Tau/4, GM Aur, and DM Tau has the
simplest form of silicates, with almost no hint of crystalline components and
modest amounts of large grains. This indicates that the dust grains in these
objects have been modified little from their origin in the interstellar medium.
Other stars show various amounts of crystalline silicates, similar to the wide
dispersion of the degree of crystallinity reported for Herbig Ae/Be stars of
mass <2.5 solar masses. Late spectral type, low-mass stars can have significant
fractions of crystalline silicate grains. Higher quartz mass fractions often
accompany low amorphous olivine-to-amorphous pyroxene ratios. It is also found
that lower contrast of the 10 micron feature accompanies greater crystallinity.Comment: AASTEX, 39 pages text, 14 figures, 4 tables, scheduled to be
published July 2006 in the Astrophysical Journa
Moonraker -- Enceladus Multiple Flyby Mission
Enceladus, an icy moon of Saturn, possesses an internal water ocean and jets
expelling ocean material into space. Cassini investigations indicated that the
subsurface ocean could be a habitable environment having a complex interaction
with the rocky core. Further investigation of the composition of the plume
formed by the jets is necessary to fully understand the ocean, its potential
habitability, and what it tells us about Enceladus' origin. Moonraker has been
proposed as an ESA M-class mission designed to orbit Saturn and perform
multiple flybys of Enceladus, focusing on traversals of the plume. The proposed
Moonraker mission consists of an ESA-provided platform, with strong heritage
from JUICE and Mars Sample Return, and carrying a suite of instruments
dedicated to plume and surface analysis. The nominal Moonraker mission has a
duration of 13.5 years. It includes a 23-flyby segment with 189 days allocated
for the science phase, and can be expanded with additional segments if
resources allow. The mission concept consists in investigating: i) the
habitability conditions of present-day Enceladus and its internal ocean, ii)
the mechanisms at play for the communication between the internal ocean and the
surface of the South Polar Terrain, and iii) the formation conditions of the
moon. Moonraker, thanks to state-of-the-art instruments representing a
significant improvement over Cassini's payload, would quantify the abundance of
key species in the plume, isotopic ratios, and physical parameters of the plume
and the surface. Such a mission would pave the way for a possible future landed
mission.Comment: Accepted for publication in The Planetary Science Journa
A patient-driven registry on Behçetâs disease: the AIDA for patients pilot project
IntroductionThis paper describes the creation and preliminary results of a patient-driven registry for the collection of patient-reported outcomes (PROs) and patient-reported experiences (PREs) in Behcet's disease (BD). MethodsThe project was coordinated by the University of Siena and the Italian patient advocacy organization SIMBA (Associazione Italiana Sindrome e Malattia di Behcet), in the context of the AIDA (AutoInflammatory Diseases Alliance) Network programme. Quality of life, fatigue, socioeconomic impact of the disease and therapeutic adherence were selected as core domains to include in the registry. ResultsRespondents were reached via SIMBA communication channels in 167 cases (83.5%) and the AIDA Network affiliated clinical centers in 33 cases (16.5%). The median value of the Behcet's Disease Quality of Life (BDQoL) score was 14 (IQR 11, range 0-30), indicating a medium quality of life, and the median Global Fatigue Index (GFI) was 38.7 (IQR 10.9, range 1-50), expressing a significant level of fatigue. The mean Beliefs about Medicines Questionnaire (BMQ) necessity-concern differential was 0.9 & PLUSMN; 1.1 (range - 1.8-4), showing that the registry participants prioritized necessity belief over concerns to a limited extent. As for the socioeconomic impact of BD, in 104 out of 187 cases (55.6%), patients had to pay from their own pocket for medical exams required to reach the diagnosis. The low family socioeconomic status (p < 0.001), the presence of any major organ involvement (p < 0.031), the presence of gastro-intestinal (p < 0.001), neurological (p = 0.012) and musculoskeletal (p = 0.022) symptoms, recurrent fever (p = 0.002), and headache (p < 0.001) were associated to a higher number of accesses to the healthcare system. Multiple linear regression showed that the BDQoL score could significantly predict the global socioeconomic impact of BD (F = 14.519, OR 1.162 [CI 0.557-1.766], p < 0.001). DiscussionPreliminary results from the AIDA for Patients BD registry were consistent with data available in the literature, confirming that PROs and PREs could be easily provided by the patient remotely to integrate physician-driven registries with complementary and reliable information
Stewart-Treves syndrome: MR imaging of a postmastectomy upper-limb chronic lymphedema with angiosarcoma
The rare occurrence of angiosarcoma in postmastectomy upper-limb lymphedema with magnetic resonance (MR) imaging is discussed. Unfamiliarity with this aggressive vascular tumor and its harmless appearance often leads to delayed diagnosis. Angiosarcoma complicating chronic lymphedema may be low in signal intensity on T2-weighting and short tau inversion recovery (STIR) imaging reflecting the densely cellular, fibrous stroma, and sparsely vascularized tumor histology. Additional administration of intravenous contrast medium revealed significant enhancement of the tumorous lesions. Awareness of angiosarcoma and its MR imaging appearance in patients with chronic lymphedema may be a key to early diagnosis or allow at least inclusion in the differential diagnosis
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