28,935 research outputs found
Studies of chemical abundances in the outer solar system
Ground-based observations and the Pioneer 10 mission have led to new discoveries and revisions of previous ideas about the outer solar system. Among these are the discovery of atmospheres on lo and Ganymede, emission from sodium and hydrogen in a cloud around lo, and the presence of acetylene, ethane, and phosphine in the atmosphere of Jupiter. Titan, the largest satellite of Saturn, continues to be an extremely interesting and baffling object, clearly very different in composition from the bodies we are familiar with in the inner solar system; this is also true of Ganymede and Callisto. New data on the abundances of methane and hydrogen in the atmospheres of Uranus and Neptune suggest that the values of C/H in these atmospheres may be much lower than had been previously thought. This result reinforces the apparent compositional differences between these two planets and Jupiter and Saturn, whose atmospheres exhibit a near-solar value for this ratio
Could icy impacts reconcile Venus with Earth and Mars
The problem of volatile sources in the martian atomosphere was studied. It is suggested that a combination of an impact by an icy planetesimal (radius about 150 km) and solar wind implantation of neon could explain the noble gas abundances on Venus. Early solar wind would supply the right amount of neon with the correct Ne-20/Ne-22 as compared with lunar soils. However, observations of noble gases in a fresh comet are needed to test this hypothesis
Spectroscopic observations of the planets Final report
Spectroscopic observations of Jupiter, Venus, and Mars atmosphere
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My Home Life: promoting quality of life in care homes
A new report from JRF outlines the findings from the My Home Life project. My Home Life is a collaborative initiative between Age UK, City University, the Joseph Rowntree Foundation and Dementia UK promoting quality of life in care homes.
This study found:
- positive relationships in care homes enable staff to listen to older people, gain insights into individual needs and facilitate greater voice, choice and control;
- relationship-centred care is at the heart of many examples of best practice;
- care home managers play a pivotal role in promoting relationships between older people, staff and relatives;
- care home providers and statutory agencies should consider how their attitudes, practices and policies can create pressure and unnecessary paperwork which ultimately reduce the capacity of care homes to respond to the needs of older people; and
- negative stereotypes of care homes have an impact on the confidence of staff and managers
Spectroscopic observations of Mars Final report, 1 Nov. 1966 - 31 Jan. 1968
Spectroscopic observations of Mars to determine carbon dioxide content of Martian atmospher
The two-star model: exact solution in the sparse regime and condensation transition
The -star model is the simplest exponential random graph model that
displays complex behavior, such as degeneracy and phase transition. Despite its
importance, this model has been solved only in the regime of dense
connectivity. In this work we solve the model in the finite connectivity
regime, far more prevalent in real world networks. We show that the model
undergoes a condensation transition from a liquid to a condensate phase along
the critical line corresponding, in the ensemble parameters space, to the
Erd\"os-R\'enyi graphs. In the fluid phase the model can produce graphs with a
narrow degree statistics, ranging from regular to Erd\"os-R\'enyi graphs, while
in the condensed phase, the "excess" degree heterogeneity condenses on a single
site with degree . This shows the unsuitability of the two-star
model, in its standard definition, to produce arbitrary finitely connected
graphs with degree heterogeneity higher than Erd\"os-R\'enyi graphs and
suggests that non-pathological variants of this model may be attained by
softening the global constraint on the two-stars, while keeping the number of
links hardly constrained.Comment: 20 pages, 3 figure
Post-Louvre intervention: did target zones stabilize the dollar?
An investigation of whether the G-3 nations (Germany, Japan, and the U.S.) successfully maintained target zones following the G-7's February 1987 Louvre meeting. Using daily, official intervention data and simultaneous-equation techniques, the authors determine that the G-3 reacted in a manner consistent with maintaining target zones, but find scant evidence that the intervention successfully influenced subsequent exchange-rate movements.Foreign exchange - Law and legislation ; Dollar, American
Cancer disease: integrative modelling approaches
Cancer is a complex disease in which a variety of phenomena interact over a wide range of spatial and temporal scales. In this article a theoretical framework will be introduced that is capable of linking together such processes to produce a detailed model of vascular tumour growth. The model is formulated as a hybrid cellular automaton and contains submodels that describe subcellular, cellular and tissue level features. Model simulations will be presented to illustrate the effect that coupling between these different elements has on the tumour's evolution and its response to chemotherapy
Pathways for Nutrient Loss to Water; Slurry and Fertilizer Spreading
End of project reportThere are almost 150,000 farms in Ireland and these contribute substantial quantities of N and P to inland and coastal waters. Some of these nutrients are carried from wet soils by overland flow and by leaching from dry soils. Farm practice can reduce the loss from farms by judicious management of nutrients. Improvements are required to diminish export of nutrients without impairing operations on the farm. Literature regarding nutrient loss from agriculture was reviewed in this project and maps were prepared to predict best slurry spreading times around Ireland. Two further maps were prepared to show slurry storage requirement on farms
Tita: discovery of carbon monoxide in its atmosphere
The 3-D rotation-vibration band of carbon monoxide was identified in the near-infrared spectrum of Titan. A preliminary mixing ratio of CO/N2 = 0.00006 was determined. This result supports the probable detection of CO2 by Samuelson et al and strengthens possible analogies between the atmosphere of Titan and conditions on the primitive Earth
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