65,276 research outputs found
Thermoluminescence of Antarctic meteorites: A rapid screening technique for terrestrial age estimation, pairing studies and identification of specimens with unusual prefall histories
Thermoluminescence (TL) is a promising technique for rapid screening of the large numbers of Antarctic meteorites, permitting identification of interesting specimens that can then be studied in detail by other, more definite techniques. Specifically, TL permits determination of rough terrestrial age, identification of potential paired groups and location of specimens with unusual pre-fall histories. Meteorites with long terrestrial ages are particularly valuable for studying transport and weathering mechanisms. Pairing studies are possible because TL variations among meteorites are large compared to variations within individual objects, especially for natural TL. Available TL data for several L3 fragments, three of which were paired by other techniques, are presented as an example of the use of TL parameters in pairing studies. Additional TL measurements, specifically a blind test, are recommended to satisfactorily establish the reliability of this pairing property. The TL measurements also identify fragments with unusual pre-fall histories, such an near-Sun orbits
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Facilitating a ‘non-judgmental’ skills-based co-design environment
This paper reflects on a pilot study for the design of a series of e-textiles workshops developed for the Nottinghamshire Mind Network community of mental health and wellbeing service users, managers and volunteers. The final workshops will form part of ‘An Internet of Soft Things’ (IoSofT) project, which seeks to develop a Person-Centred Approach (PCA) to design. The workshops should be experienced by participants as a non-judgemental environment, as one of the conditions of the Person-Centred Approach – unconditional positive regard (UPR) (Rogers, 1957). While the research team agree in theory that participants should feel safe and supported, putting non-judgement into practice in a multi - disciplinary environment, in which skills form the basis of workshop activity, has proved to be challenging. The paper introduces the key criteria of the PCA in psychotherapy, and describes the particular challenges that being non-judgemental presented to the textile designers and therapeutic practitioners who designed and facilitated the workshops. It presents an analysis of the design artefacts produced in the course of six workshop sessions (such as the ‘group agreement’), and participant feedback, and discusses the resulting framework that will be applied in the next iteration of workshops to enable participants’ comfort, creativity and autonomy
The effects on health of a publicly funded domestic heating programme: a prospective controlled study
<b>Objective</b>: To assess the effect of a publicly funded domestic heating programme on self-reported health.
<b>Design, setting and participants</b>: A prospective controlled study of 1281 households in Scotland receiving new central heating under a publicly funded initiative, and 1084 comparison households not receiving new heating. The main outcome measures were self-reported diagnosis of asthma, bronchitis, eczema, nasal allergy, heart disease, circulatory problems or high blood pressure; number of primary care encounters and hospital contacts in the past year; and SF-36 Health Survey scores.
<b>Results</b>: Usable data were obtained from 61.4% of 3849 respondents originally recruited. Heating recipients reported higher scores on the SF-36 Physical Functioning scale (difference 2.51; 95% CI 0.67 to 4.37) and General Health scale (difference 2.57; 95% CI 0.90 to 4.34). They were less likely to report having received a first diagnosis of heart disease (OR 0.69; 95% CI 0.52 to 0.91) or high blood pressure (OR 0.77; 95% CI 0.61 to 0.97), but the groups did not differ significantly in use of primary care or hospital services.
<b>Conclusions</b>: Provision of central heating was associated with significant positive effects on general health and physical functioning; however, effect sizes were small. Evidence of a reduced risk of first diagnosis with heart disease or high blood pressure must be interpreted with caution, due to the self-reported nature of the outcomes, the limited time period and the failure to detect any difference in health service use
Psychological interventions for mental health disorders in children with chronic physical illness: a systematic review.
Children with chronic physical illness are significantly more likely to develop common psychiatric symptoms than otherwise healthy children. These children therefore warrant effective integrated healthcare yet it is not established whether the known, effective, psychological treatments for symptoms of common childhood mental health disorders work in children with chronic physical illness
Nucleon and Delta masses in twisted mass chiral perturbation theory
We calculate the masses of the nucleons and deltas in twisted mass heavy
baryon chiral perturbation theory. We work to quadratic order in a power
counting scheme in which we treat the lattice spacing and the quark masses to
be of the same order. We give expressions for the mass and the mass splitting
of the nucleons and deltas both in and away from the isospin limit. We give an
argument using the chiral Lagrangian treatment that, in the strong isospin
limit, the nucleons remain degenerate and the delta multiplet breaks into two
degenerate pairs to all orders in chiral perturbation theory. We show that the
mass splitting between the degenerate pairs of the deltas first appears at
quadratic order in in the lattice spacing. We discuss the subtleties in the
effective chiral theory that arise from the inclusion of isospin breaking.Comment: 21 pages, 4 figures, version published in PR
Electron transport in Coulomb- and tunnel-coupled one-dimensional systems
We develop a linear theory of electron transport for a system of two
identical quantum wires in a wide range of the wire length L, unifying both the
ballistic and diffusive transport regimes. The microscopic model, involving the
interaction of electrons with each other and with bulk acoustical phonons
allows a reduction of the quantum kinetic equation to a set of coupled
equations for the local chemical potentials for forward- and backward-moving
electrons in the wires. As an application of the general solution of these
equations, we consider different kinds of electrical contacts to the
double-wire system and calculate the direct resistance, the transresistance, in
the presence of tunneling and Coulomb drag, and the tunneling resistance. If L
is smaller than the backscattering length l_P, both the tunneling and the drag
lead to a negative transresistance, while in the diffusive regime (L >>l_P) the
tunneling opposes the drag and leads to a positive transresistance. If L is
smaller than the phase-breaking length, the tunneling leads to interference
oscillations of the resistances that are damped exponentially with L.Comment: Text 14 pages in Latex/Revtex format, 4 Postscript figure
Control of common scab without the use of water
The most effective way to control common scab is by irrigating a potato crop at tuber initiation. With the introduction of legislation such as the Water Framework Directive this will become increasingly difficult. In this field experiment, we assessed the potential of a number of non-water measures for controlling this disease. Common scab on daughter tubers at harvest was reduced by applying rapeseed meal at 1 t ha-1 to the beds and then incorporating it into the soil, and adding a mixture of Trichoderma viride isolates into the furrow at planting. None of these treatments was as effective as using water
Influence of Visual Feedback On Dynamic Balance Control in Chronic Stroke Survivors
Chronic stroke survivors have an increased incidence of falls during walking, suggesting changes in dynamic balance control post-stroke. Despite this increased incidence of falls during walking, balance control is often studied only in standing. The purpose of this study was to quantify deficits in dynamic balance control during walking, and to evaluate the influence of visual feedback on this control in stroke survivors. Ten individuals with chronic stroke, and ten neurologically intact individuals participated in this study. Walking performance was assessed while participants walked on an instrumented split-belt treadmill with different types of visual feedback. Dynamic balance control was quantified using both the extent of center of mass (COM) movement in the frontal plane over a gait cycle (COM sway), and base of support (step width). Stroke survivors walked with larger COM sway and wider step widths compared to controls. Despite these baseline differences, both groups walked with a similar ratio of step width to COM sway (SW/COM). Providing a stationary target with a laser reference of body movement reduced COM sway only in the stroke group, indicating that visual feedback of sway alters dynamic balance control post-stroke. These results demonstrate that stroke survivors attempt to maintain a similar ratio of step width to COM movement, and visual cues can be used to help control COM movement during walking post-stroke
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