Optimal shield mass distribution for space radiation protection

Computational methods have been developed and successfully used for determining the optimum distribution of space radiation shielding on geometrically complex space vehicles. These methods have been incorporated in computer program SWORD for dose evaluation in complex geometry, and iteratively calculating the optimum distribution for (minimum) shield mass satisfying multiple acute and protected dose constraints associated with each of several body organs

Methods of space radiation dose analysis with applications to manned space systems

The full potential of state-of-the-art space radiation dose analysis for manned missions has not been exploited. Point doses have been overemphasized, and the critical dose to the bone marrow has been only crudely approximated, despite the existence of detailed man models and computer codes for dose integration in complex geometries. The method presented makes it practical to account for the geometrical detail of the astronaut as well as the vehicle. Discussed are the major assumptions involved and the concept of applying the results of detailed proton dose analysis to the real-time interpretation of on-board dosimetric measurements

Signatures of exchange correlations in the thermopower of quantum dots

We use a many-body rate-equation approach to calculate the thermopower of a quantum dot in the presence of an exchange interaction. At temperatures much smaller than the single-particle level spacing, the known quantum jumps (discontinuities) in the thermopower are split by the exchange interaction. The origin and nature of the splitting are elucidated with a simple physical argument based on the nature of the intermediate excited state in the sequential tunneling approach. We show that this splitting is sensitive to the number parity of electrons in the dot and the dot's ground-state spin. These effects are suppressed when cotunneling dominates the electrical and thermal conductances. We calculate the thermopower in the presence of elastic cotunneling, and show that some signatures of exchange correlations should still be observed with current experimental methods. In particular, we propose a method to determine the strength of the exchange interaction from measurements of the thermopower.Comment: 18 pages, 6 figures Revised figure 6, and changed discussion of figure

The 2008 August 1 Eclipse Solar-Minimum Corona Unraveled

We discuss results stemming from observations of the white-light and [Fe XIV] emission corona during the total eclipse of the Sun of 2008 August 1, in Mongolia (Altaj region) and in Russia (Akademgorodok, Novosibirsk, Siberia). Corresponding to the current extreme solar minimum, the white-light corona, visible up to 20 solar radii, was of a transient type with well-pronounced helmet streamers situated above a chain of prominences at position angles 48, 130, 241 and 322 degrees. A variety of coronal holes, filled with a number of thin polar plumes, were seen around the poles. Furthering an original method of image processing, stars up to 12 magnitude, a Kreutz-group comet (C/2008 O1), and a coronal mass ejection (CME) were also detected, with the smallest resolvable structures being of, and at some places even less than, 1 arcsec. Differences, presumably motions, in the corona and prominences are seen even with the 19-min time difference between our sites. In addition to the high-resolution coronal images, which show the continuum corona (K-corona) that results from electron scattering of photospheric light, images of the overlapping green-emission-line (530.3 nm, [Fe XIV]) corona were obtained with the help of two narrow-passband filters (centered on the line itself and for the continuum in the vicinity of 529.1 nm, respectively), each with FWHM of 0.15 nm. Through solar observations, on whose scheduling and details we consulted, with the Solar and Heliospheric Observatory, Hinode's XRT and SOT, TRACE, and STEREO, as well as Wilcox Solar Observatory and SOHO/MDI magnetograms, we set our eclipse observations in the context of the current unusually low and prolonged solar minimum.Comment: Accepted in The Astrophysical Journal, 6 July 200

Switching barrier scaling near bifurcation points for non-Gaussian noise

We study noise-induced switching of a system close to bifurcation parameter values where the number of stable states changes. For non-Gaussian noise, the switching exponent, which gives the logarithm of the switching rate, displays a non-power-law dependence on the distance to the bifurcation point. This dependence is found for Poisson noise. Even weak additional Gaussian noise dominates switching sufficiently close to the bifurcation point, leading to a crossover in the behavior of the switching exponent

Driver behaviour with adaptive cruise control

This paper reports on the evaluation of adaptive cruise control (ACC) from a psychological perspective. It was anticipated that ACC would have an effect upon the psychology of driving, i.e. make the driver feel like they have less control, reduce the level of trust in the vehicle, make drivers less situationally aware, but workload might be reduced and driving might be less stressful. Drivers were asked to drive in a driving simulator under manual and ACC conditions. Analysis of variance techniques were used to determine the effects of workload (i.e. amount of traffic) and feedback (i.e. degree of information from the ACC system) on the psychological variables measured (i.e. locus of control, trust, workload, stress, mental models and situation awareness). The results showed that: locus of control and trust were unaffected by ACC, whereas situation awareness, workload and stress were reduced by ACC. Ways of improving situation awareness could include cues to help the driver predict vehicle trajectory and identify conflicts

Privacy and Dignity in Continence Care Project Phase 2.

This report provides an account of the methods and findings of Phase 2 of the Privacy and Dignity in Continence Care for Older People study funded by the Royal College of Physicians and the British Geriatrics Society. The overall objectives of this two year project were to: • Identify and validate person-centred attributes of dignity in relation to continence; • Develop reflective guidelines for dignified care; • Produce recommendations for best practice

In Situ Localization and Characterization of Active Proteases in Chronically Inflamed and Healthy Human Gingival Tissues

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141400/1/jper1303.pd

'He just gave up': an exploratory study into the perspectives of paid carers on supporting older people living in care homes with depression, self-harm, and suicide ideation and behaviours

This study explored the concept of ‘giving up’ from the perspective of care staff working in care homes, and their everyday communication and hidden knowledge concerning what they think about this taboo topic and the context it reflects. Moving to a care home is a major transition where cumulative losses can pose risks to mental health in later life. If not recognised, this vulnerability can lead to depression which extends to suicide ideation and behaviours in the form of self-harm and self-neglect. Care homes are a significant place of care until death, yet a discourse of silence means that self-harm and suicide is under-reported or not attended to with specialist expertise. The layperson’s concept of an older person ‘giving up’ on life is hardly discussed in the literature. This co-produced qualitative study used an inductive approach to explore this phenomenon through focus groups with 33 care staff across four care homes in South-East England. Findings paint a complex picture, highlighting tensions in providing the right support and creating spaces to respond to such challenging situations. ‘Giving up’ requires skilled detailed assessment to respond to risks alongside improved training and support for paid carers, to achieve a more holistic strategy which capitalises on significant relationships within a wider context

Analysis of In Situ Protease Activity in Chronic Adult Periodontitis Patients: Expression of Activated MMP‐2 and a 40 kDa Serine Protease

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141775/1/jper0353.pd