Heat flow and heat generation in greenstone belts

Heat flow has been measured in Precambrian shields in both greenstone belts and crystalline terrains. Values are generally low, reflecting the great age and tectonic stability of the shields; they range typically between 30 and 50 mW/sq m, although extreme values of 18 and 79 mW/sq m have been reported. For large areas of the Earth's surface that are assumed to have been subjected to a common thermotectonic event, plots of heat flow against heat generation appear to be linear, although there may be considerable scatter in the data. The relationship is expressed as: Q = Q sub o + D A sub o in which Q is the observed heat flow, A sub o is the measured heat generation at the surface, Q sub o is the reduced heat flow from the lower crust and mantle, and D, which has the dimension of length, represents a scale depth for the distribution of radiogenic elements. Most authors have not used data from greenstone belts in attempting to define the relationship within shields, considering them unrepresentative and preferring to use data from relatively homogeneous crystalline rocks. A discussion follows

Polyomino Word-Puzzle Results

In our last issue we presented a near-solution to one of the pentomino word-problems. Now J.A. Lindon has arrived at the first complete solution to one of these problems, which we present at the end of this article. At the same time, Donald A. Drury, who provides (below) suggestions for solving some lower order trimino problems, has written to point out, concerning all these polyomino word-problems: To make the reflection a new problem, you must rule out using the same words in any diagram as were used in its reflected opposite. Otherwise, by simply using the same words in reverse order, top to bottom, you can solve both Rotation X and Reflection X

The biographical consequences of protest and activism: a systematic review and a new typology

Most research on activist participation has aimed to explain motives to engage in protest and collective action or becoming an activist. The outcomes, for the individual, have been neglected. Therefore, we set out to systematically document and organize the psychological and behavioural changes associated with activism into a typology of change. The review contains 57 papers describing changes. Psychological changes identified in the literature can be classified into 19 main forms: marital status, children, relationship ties, work-life/career, extended involvement, consumer behaviour, identity, empowerment, radicalization/politicization, legitimacy, sustained commitment, self-esteem, general well-being, ‘traits’, self-confidence, religion, organizing, knowledge and home skills. Our analysis highlights the lack of analysis of the relation between type of protest and type of change, and lack of research into the processes behind the various psychological changes. What is needed now is more precise investigation of the relationship between types of protests, social and psychological processes, and psychological outcomes. Further, more longitudinal studies are required to explore the relationship

The Physiological Consequences of Bed Rest

Bed rest often is used to treat a wide variety of medical conditions. However, bed rest results in profound deconditioning of the body. Bed rest reduces the hydrostatic pressure gradient within the cardiovascular system, reduces muscle force production, virtually eliminates compression on the bones, and lowers total energy expenditure. This review focuses on the deconditioning that occurs in the cardiovascular, muscular, and skeletal systems following bed rest. Reduction in plasma volume reduces cardiac preload, stroke volume, cardiac output, and ultimately, maximal oxygen consumption. Skeletal muscle volume, muscle cross sectional area, and fiber cross sectional area decrease, which results in diminished muscular strength. These changes are most pronounced in the antigravity muscles. Increased bone resorption leads to a negative calcium balance and eventually decreased bone mass, particularly in the lower limbs. Diminished bone mass coupled with decreased muscular strength increases the risk of bone fractures, even with minor falls. It is important for clinicians to recognize these negative consequences of bed rest, which can be explained independent of disease or disorder. With this in mind, bed rest can be minimized as much as possible and early ambulation and physical activity may be prescribed to limit the deconditioning effects of bed rest

Interpreting the Cosmic Ray Composition

Detailed composition measurements can be a very powerful means of tracing origins, a fact used regularly by forensic scientists and art historians. One of the main motivating factors for making detailed observations of cosmic rays was always the hope that a unique compositional signature could be found which pointed unambiguously to a particular source. This has proven much harder than expected, but we have now reached a point where it appears possible to begin to decipher the information contained in the compositional data; the key, we have discovered, is to read the data not in isolation, but in the context provided by our general astronomical knowledge and by recent developments in shock acceleration theory (Meyer, Drury and Ellison, 1997, 1998; Ellison, Drury and Meyer, 1997). In our view (not, it is only fair to warn the reader, yet universally accepted) the data show clearly that the Galactic cosmic ray particles originate predominantly from the gas and dust of the general interstellar medium.Comment: 14 pages, LaTeX 2.09, 4 figure

Reasons for adopting different capacity levels in the denominator of overhead rates: a research note

There has been criticism of the use of budgeted capacity as the denominator of overhead rates. Prior questionnaire-based research has analysed which type of capacity is used in the denominator of overhead rates, but it has not assessed why these capacity levels are used. This paper uses grounded theory techniques to analyse 50 interviews with British management accountants about why a particular capacity level is used to determine the denominator of overhead rates. The results reveal that budgeted capacity is used because the calculation of the denominator is regarded as part of the budgeting process. Practical capacity and normal capacity are used to ensure that products are not under or overcosted

Public experiences of mass casualty decontamination

In this article, we analyze feedback from simulated casualties who took part in field exercises involving mass decontamination, to gain an understanding of how responder communication can affect people’s experiences of and compliance with decontamination. We analyzed questionnaire data gathered from 402 volunteers using the framework approach, to provide an insight into the public’s experiences of decontamination and how these experiences are shaped by the actions of emergency responders. Factors that affected casualties’ experiences of the econtamination process included the need for greater practical information and better communication from responders, and the need for privacy. Results support previous findings from small-scale incidents that involved decontamination in showing that participants wanted better communication from responders during the process of decontamination, including more practical information, and that the failure of responders to communicate effectively with members of the public led to anxiety about the decontamination process. The similarity between the findings from the exercises described in this article and previous research into real incidents involving decontamination suggests that field exercises provide a useful way to examine the effect of responder communication strategies on the public’s experiences of decontamination. Future exercises should examine in more detail the effect of various communication strategies on the public’s experiences of decontamination. This will facilitate the development of evidence-based communication strategies intended to reduce anxiety about decontamination and increase compliance among members of the public during real-life incidents that involve mass decontamination