4,050 research outputs found
Space Trajectory Error Analysis Program (STEAP) for halo orbit missions. Volume 2: Programmer's manual
The six month effort was responsible for the development, test, conversion, and documentation of computer software for the mission analysis of missions to halo orbits about libration points in the earth-sun system. The software consisting of two programs called NOMNAL and ERRAN is part of the Space Trajectories Error Analysis Programs. The program NOMNAL targets a transfer trajectory from earth on a given launch date to a specified halo orbit on a required arrival date. Either impulsive or finite thrust insertion maneuvers into halo orbit are permitted by the program. The transfer trajectory is consistent with a realistic launch profile input by the user. The second program ERRAN conducts error analyses of the targeted transfer trajectory. Measurements including range, doppler, star-planet angles, and apparent planet diameter are processed in a Kalman-Schmidt filter to determine the trajectory knowledge uncertainty
Increased HCO production in the outer disk around HD 163296
Three formaldehyde lines were observed (HCO 3--2, HCO
3--2, and HCO 3--2) in the protoplanetary disk
around the Herbig Ae star HD 163296 with ALMA at 0.5 arcsecond (60 AU) spatial
resolution. HCO 3--2 was readily detected via imaging, while
the weaker HCO 3--2 and HCO 3--2 lines
required matched filter analysis to detect. HCO is present throughout most
of the gaseous disk, extending out to 550 AU. An apparent 50 AU inner radius of
the HCO emission is likely caused by an optically thick dust continuum. The
HCO radial intensity profile shows a peak at 100 AU and a secondary bump at
around 300 AU, suggesting increased production in the outer disk. Different
parameterizations of the HCO abundance were compared to the observed
visibilities with minimization, using either a characteristic
temperature, a characteristic radius or a radial power law index to describe
the HCO chemistry. Similar models were applied to ALMA Science Verification
data of CO. In all modeling scenarios, fits to the HCO data show an
increased abundance in the outer disk. The overall best-fit HCO model shows
a factor of two enhancement beyond a radius of 27020 AU, with an inner
abundance of . The HCO emitting region has a lower
limit on the kinetic temperature of K. The CO modeling suggests
an order of magnitude depletion in the outer disk and an abundance of in the inner disk. The increase in HCO outer disk emission
could be a result of hydrogenation of CO ices on dust grains that are then
sublimated via thermal desorption or UV photodesorption, or more efficient
gas-phase production beyond about 300 AU if CO is photodisocciated in this
region
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'Abandoned by Medicine'? A qualitative study of women's experiences with lymphoedema secondary to cancer, and the implications for care
Background: Lymphoedema secondary to cancer is a relatively neglected and under-researched condition. Few studies report people's experiences of care and treatment provision when living with the condition. Current practice focuses on the physical treatment yet psychosocial needs often remain unmet. A previous study examining the patient perspective identified the theme of being ‘abandoned by medicine’. Perceived lack of support may result in a delayed adaptation and acceptance of this long-term condition and can significantly impact on psychological well-being. We explore this emerging theme alongside others in order to provide a guide to action for improvements for patient benefit.
Aim: The central aim was to explore women's views of their care and treatment following a diagnosis with lymphoedema secondary to cancer. This forms part of a larger study aimed at assessing appropriate screening tools to measure psychosocial distress.
Methods: A mixed-methods approach was used for the main study. Here we report the qualitative component, derived from in-depth semi-structured interviews conducted in the homes of the participants (n = 14) and focus group discussions (n = 15). In addition, qualitative comments from questionnaire data from a large-scale postal survey are included (n = 104).
Findings: Participants identified considerable deficiencies in health care workers’ knowledge and awareness of lymphoedema, which subsequently impacted on the patients’ needs for information, support and understanding. Access to appropriate treatment was patchy and problems were identified with the process of obtaining compression garments, massage and other sources of help. Although lymphoedema is a long-term disfiguring condition, and much is known about how this impacts on patients’ emotional well-being, little attention was paid by health professionals to potential psychosocial consequences. In essence women had to become experts of their own condition and cope as best as they could. We provide recommendations to improve service delivery and address these unmet needs
NEW RECORDS FOR \u3ci\u3eACERIA ANTHOCOPTES\u3c/i\u3e (ACARI: ERIOPHYIDAE) OCCURRING ON CANADA THISTLE IN COLORADO, NEBRASKA, AND WYOMING, U.S.A.
Canada thistle [Cirsium arvense (L.) Scop.] growing in eastern Colorado, Wyoming and western Nebraska were surveyed for the presence and distribution of Aceria anthocoptes (Nal.). Of the 34 sites surveyed in 2004, mites were abundant at 42%, present in lesser numbers at 52%, and not present at 6% of the sites. In 2005, two new sites were added and ten sites sampled in 2004 were revisited. Of these 12 sites, mites were abundant at 17%, present to a lesser extent at 58%, and not present at 25% of the sites. The results demonstrate that Canada thistle growing in this region commonly harbor A. anthocoptes. How long A. anthocoptes has been present in this region is unknown, however, anecdotal evidence demonstrating a dramatic decline in the population of Canada thistle at one Colorado site from 2000 to 2007 suggests that the mite may have been present since 2002
Synthetic Mudscapes: Human Interventions in Deltaic Land Building
In order to defend infrastructure, economy, and settlement in Southeast Louisiana, we must construct new land to
mitigate increasing risk. Links between urban environments and economic drivers have constrained the dynamic delta
landscape for generations, now threatening to undermine the ecological fitness of the entire region. Static methods of
measuring, controlling, and valuing land fail in an environment that is constantly in flux; change and indeterminacy are
denied by traditional inhabitation.
Multiple land building practices reintroduce deltaic fluctuation and strategic deposition of fertile material to form the
foundations of a multi-layered defence strategy. Manufactured marshlands reduce exposure to storm surge further
inland. Virtual monitoring and communication networks inform design decisions and land use becomes determined
by its ecological health. Mudscapes at the threshold of land and water place new value on former wastelands. The
social, economic, and ecological evolution of the region are defended by an expanded web of growing land
Why witnesses of bullying tell: Individual and interpersonal factors
The reactions of those who witness bullying are important because they can stop the bullying and prevent further harm. Factors associated with telling behavior were investigated with 477 elementary school students who witnessed bullying. Approximately seventy percent of the students talked to someone about bullying incidents, most often, teachers. Chi-square and logistic regression analyses demonstrated that gender, frequency of witnessing, cognitive empathy, and social skills were found to be associated with telling behavior of witnesses, whereas affective empathy and school connectedness were not significantly related. Findings from this research are important for future practice and studies on bystander intervention
Stars of extragalactic origin in the solar neighborhood
We computed the spatial velocities and the galactic orbital elements using
Hipparcos data for 77 nearest main-sequence F-G-stars with published the iron,
magnesium, and europium abundances determined from high dispersion spectra and
with the ages estimated from theoretical isochrones. A comparison with the
orbital elements of the globular clusters that are known was accreted by our
Galaxy in the past reveals stars of extragalactic origin. We show that the
relative elemental abundance ratios of r- and \alpha- elements in all the
accreted stars differ sharply from those in the stars that are genetically
associated with the Galaxy. According to current theoretical models, europium
is produced mainly in low mass Type II supernovae (SNe II), while magnesium is
synthesized in larger amounts in high mass SN II progenitors. Since all the old
accreted stars of our sample exhibit a significant Eu overabundance relative to
Mg, we conclude that the maximum masses of the SNII progenitors outside the
Galaxy were much lower than those inside it are. On the other hand, only a
small number of young accreted stars exhibit low negative ratios .
The delay of primordial star formation burst and the explosions of high mass
SNe II in a relatively small part of extragalactic space can explain this
situation. We provide evidence that the interstellar medium was weakly mixed at
the early evolutionary stages of the Galaxy formed from a single proto-galactic
cloud and that the maximum mass of the SN II progenitors increased in it with
time simultaneously with the increase in mean metallicity.Comment: Accepted for 2004, Astronomy Letters, Vol. 30, No. 3, P.148-158 15
pages, 3 figure
Spectroscopy of high proper motion stars in the ground--based UV
Based on high quality spectral data (spectral resolution R>60000) within the
wavelength range of 3550-5000 AA we determined main parameters (effective
temperature, surface gravity, microturbulent velocity, and chemical element
abundances including heavy metals from Sr to Dy) for 14 metal-deficient G-K
stars with large proper motions. The stars we studied have a wide range of
metallicity: [Fe/H]=-0.3 \div -2.9. Abundances of Mg, Al, Sr and Ba were
calculated with non-LTE line-formation effects accounted for. Abundances both
of the radioactive element Th and r-process element Eu were determined using
synthetic spectrum calculations. We selected stars that belong to different
galactic populations according to the kinematical criterion and parameters
determined by us. We found that the studied stars with large proper motions
refer to different components of the Galaxy: thin, thick disks and halo. The
chemical composition of the star BD+80 245 located far from the galactic plane
agrees with its belonging to the accreted halo. For the giant HD115444 we
obtained [Fe/H]=-2.91, underabundance of Mn, overabundance of heavy metals from
Ba to Dy, and, especially high excess of the r-process element Europium:
[Eu/Fe]=+1.26. Contrary to its chemical composition typical for halo stars,
HD115444 belongs to the disc population according to its kinematic parameters.Comment: 16 pages, 4 figures, 5 tables, "UV Universe-2010 (2nd NUVA Symposium)
conference
Optical/IR from ground
Optical/infrared (O/IR) astronomy in the 1990's is reviewed. The following subject areas are included: research environment; science opportunities; technical development of the 1980's and opportunities for the 1990's; and ground-based O/IR astronomy outside the U.S. Recommendations are presented for: (1) large scale programs (Priority 1: a coordinated program for large O/IR telescopes); (2) medium scale programs (Priority 1: a coordinated program for high angular resolution; Priority 2: a new generation of 4-m class telescopes); (3) small scale programs (Priority 1: near-IR and optical all-sky surveys; Priority 2: a National Astrometric Facility); and (4) infrastructure issues (develop, purchase, and distribute optical CCDs and infrared arrays; a program to support large optics technology; a new generation of large filled aperture telescopes; a program to archive and disseminate astronomical databases; and a program for training new instrumentalists
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