Pulsed energy power system Patent

Pulsed energy power system for application of combustible gases to turbine controlling ac voltage generato

Infrared emissivities and absorptivities of gases

Approximate analytic expressions are obtained for the "effective band widths" and emissivities of diatomic molecules at elevated pressures. The absorptivities of molecular vibration‐rotation bands are evaluated for radiation emitted by similar molecular vibration‐rotation bands and for radiation emitted by blackbodies. The results obtained for the absorptivity calculations compare favorably with available empirical correlations for H_2O. The postulated model does not apply to CO_2 and, therefore, no satisfactory theoretical formula has been derived for the absorptivities of this molecule. The appendix (by A. Thomson) is devoted to a critical examination of the limits of validity of the effective band‐width concept for different molecules

Environmental statistics and optimal regulation

Any organism is embedded in an environment that changes over time. The timescale for and statistics of environmental change, the precision with which the organism can detect its environment, and the costs and benefits of particular protein expression levels all will affect the suitability of different strategies-such as constitutive expression or graded response-for regulating protein levels in response to environmental inputs. We propose a general framework-here specifically applied to the enzymatic regulation of metabolism in response to changing concentrations of a basic nutrient-to predict the optimal regulatory strategy given the statistics of fluctuations in the environment and measurement apparatus, respectively, and the costs associated with enzyme production. We use this framework to address three fundamental questions: (i) when a cell should prefer thresholding to a graded response; (ii) when there is a fitness advantage to implementing a Bayesian decision rule; and (iii) when retaining memory of the past provides a selective advantage. We specifically find that: (i) relative convexity of enzyme expression cost and benefit influences the fitness of thresholding or graded responses; (ii) intermediate levels of measurement uncertainty call for a sophisticated Bayesian decision rule; and (iii) in dynamic contexts, intermediate levels of uncertainty call for retaining memory of the past. Statistical properties of the environment, such as variability and correlation times, set optimal biochemical parameters, such as thresholds and decay rates in signaling pathways. Our framework provides a theoretical basis for interpreting molecular signal processing algorithms and a classification scheme that organizes known regulatory strategies and may help conceptualize heretofore unknown ones.Comment: 21 pages, 7 figure

Power in global agriculture: economics, politics, and natural resources

Recent events, such as the 2008 food price crisis, have focussed global attention on the agriculture and food sectors. In particular, many countries have become increasingly concerned with the issue of ensuring the security of their food supply and one key element of this is who has power within the food supply chain. Through examining three dimensions of power – Economic, Political, and Natural Resources – this paper explores where power currently lies in world agriculture and how this might change in the future. Whilst recognising that power is a somewhat abstract concept, through a process of deriving potential indicators, a picture of the distribution of power is drawn. These indicators were also used to develop a simple 'global power index'. The power index indicates that the US and the EU dominate world agriculture in terms of economics and politics, but are potentially vulnerable in terms of their possession of natural resources. On the other hand, the emerging economies have lower political and corporate power, but seem better placed in terms of natural resources. The paper concludes by discussing the implications of these findings for the main food producing regions

Assessing the health impact of local amenities: a qualitative study of contrasting experiences of local swimming pool and leisure provision in two areas of Glasgow

Study objective: To assess the health impacts of local public swimming pool and leisure provision. Design: Retrospective qualitative study using focus groups. Reports from two areas with contrasting experience of provision of a public swimming pool (opening and closure) were compared within the context of general reports about health and neighbourhood. Setting: Two deprived neighbourhoods in south Glasgow. Participants: Local adult residents of mixed ages, accessed through local community groups. Main results: In both areas the swimming pool was reported as an important amenity that was linked to health and wellbeing. However, few residents reported regular use of the pool for physical activity. Use of the pool facility for social contact was directly linked to reports of relief of stress and isolation, and improved mental health. Pool closure was one in a series of amenity closures and area decline and was used to represent other area changes. Health impacts were strongly linked to the pool closure. The pool opening was associated with local area regeneration, similar but less prominent links between swimming pool provision and health were reported. Health benefits of social contact were diffuse and linked to other local amenities as well as the new pool facility. Conclusions: Although theoretically linked to increased physical activity, the health benefits conveyed by the swimming pool may be more closely linked to the facilitation of social contact, and a supervised facility for young children. The use of qualitative work to investigate area based change provides rich contextual data to strengthen and explain the reported health impacts

Performance of Particle Flow Calorimetry at CLIC

The particle flow approach to calorimetry can provide unprecedented jet energy resolution at a future high energy collider, such as the International Linear Collider (ILC). However, the use of particle flow calorimetry at the proposed multi-TeV Compact Linear Collider (CLIC) poses a number of significant new challenges. At higher jet energies, detector occupancies increase, and it becomes increasingly difficult to resolve energy deposits from individual particles. The experimental conditions at CLIC are also significantly more challenging than those at previous electron-positron colliders, with increased levels of beam-induced backgrounds combined with a bunch spacing of only 0.5 ns. This paper describes the modifications made to the PandoraPFA particle flow algorithm to improve the jet energy reconstruction for jet energies above 250 GeV. It then introduces a combination of timing and p_T cuts that can be applied to reconstructed particles in order to significantly reduce the background. A systematic study is performed to understand the dependence of the jet energy resolution on the jet energy and angle, and the physics performance is assessed via a study of the energy and mass resolution of W and Z particles in the presence of background at CLIC. Finally, the missing transverse momentum resolution is presented, and the fake missing momentum is quantified. The results presented in this paper demonstrate that high granularity particle flow calorimetry leads to a robust and high resolution reconstruction of jet energies and di-jet masses at CLIC.Comment: 14 pages, 11 figure

Evaluation of GHA’s youth diversionary programme

To assist with funding decisions in this area and to build an evidence base, GHA commissioned an evaluation of a selection of its youth diversionary programmes in 2007