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Software engineering challenges: Achieving zero carbon buildings by 2019
The planet Earth is warming up. There is an urgent need to reduce greenhouse gas emissions. Buildings account for almost 50% of UK carbon dioxide emissions. [1] The UK Government have set out a programme to make all new buildings zero carbon by 2019. This will require a paradigm shift in how buildings are designed, with an increased reliance on computational modelling of building performance early in the design process.
This paper outlines how architects have traditionally worked, the available software and how it is used. It discusses the challenges faced by building designers in achieving zero carbon buildings and then outlines how software tools might develop to meet not only the zero carbon challenge but also take the concept further to help design sustainable buildings
Introduction: Religion and Victorian Popular Literature
The introduction to this special issue of the Victorian Popular Fictions Journal, “Religion and Victorian Popular Literature,” opens by using Mary Ward’s best-seller Robert Elsmere (1888) as a case study for considering how recent critical strategies for engaging with popular texts enable us to paint a different and more complex picture of the Victorian religious landscape. We then explain the different ways in which our international network of contributors reconceptualises the relationship of religion to popular literary genres including the transatlantic social gospel, science writing for children, and popular yoga texts. We identify how topics as diverse as astronomy, copyright, and disaster fiction, which have often been examined through a primarily secular lens, can be better understood by considering the role religion played in their formation and articulation within and through popular literature. Drawing together threads shared between the seven articles in the special issue, we outline its key thematic contributions in exploring the role of religion to the formation of new literary markets and genres, revising the “conflict thesis” between religion and science, and the importance of popular literary forms in constructing and communicating theological ideas, as well as responding to recent calls to decolonise Victorian Studies
Mathematical modelling and optimisation of a water heat pump
The purpose of the work described here has been to seek methods of narrowing the present gap between currently realised heat pump performance and the theoretical limit. The single most important pre-requisite to this objective is the identification and quantitative assessment of the various non-idealities and degradative phenomena responsible for the present shortfall. The use of availability analysis has been introduced as a diagnostic tool, and applied to a few very simple, highly idealised Rankine cycle optimisation problems. From this work, it has been demonstrated that the scope for improvement through optimisation is small in comparison with the extensive potential for improvement by reducing the compressor's losses. A fully instrumented heat pump was assembled and extensively tested. This furnished performance data, and led to an improved understanding of the systems behaviour. From a very simple analysis of the resulting compressor performance data, confirmation of the compressor's low efficiency was obtained. In addition, in order to obtain experimental data concerning specific details of the heat pump's operation, several novel experiments were performed. The experimental work was concluded with a set of tests which attempted to obtain definitive performance data for a small set of discrete operating conditions. These tests included an investigation of the effect of two compressor modifications. The resulting performance data was analysed by a sophisticated calculation which used that measurements to quantify each dagradative phenomenon occurring in that compressor, and so indicate where the greatest potential for improvement lies. Finally, in the light of everything that was learnt, specific technical suggestions have been made, to reduce the losses associated with both the refrigerant circuit and the compressor
Partial inhibition of ABA-induced stomatal closure by calcium-channel blockers.
ABA-induced increases in [Ca2+]cyt (cytosolic free Ca2+) may result from Ca2+ influx from the apoplast and/or release from intracellular stores. In this paper, Ca2+-channel blockers have been used to investigate this question in the detached epidermis of Commelina communis. Examples from the benzothiazepine, dihydropyridine and phenylalkylamine series all inhibited ABA-induced stomatal closure: (+/-) verapamil > nifedipine > diltiazem. Inhibition was partial, the magnitude of the effect being dependent on both the concentration of ABA and that of the channel blocker. The maximum inhibition observed in the presence of 100 nM ABA was approximately 66% at high (100 nM) concentrations of (+/-) verapamil or nifedipine. In the near absence of extracellular Ca2+ (2 mM EGTA) ABA-induced stomatal closure was reduced by approximately 22% and the inhibition by Ca2+-channel blockers abolished. Inhibition by (+/-) verapamil was totally reversible and exhibited signs of stereospecificity, the s(-) enantiomer being a more potent inhibitor of ABA-induced stomatal closure than the R(+) enantiomer. Bay K 8644 (a fluorinated analogue of nifedipine) exhibited biphasic action on 500 uM Ca2+-induced stomatal closure, i.e. agonistic at low concentrations (10 nM), antagonistic at high concentrations (> 10 nM to 100 uM), but did not affect ABA-induced stomatal closure. These results suggest that Ca2+ release from intracellular stores may be important in the ABA-induced increase in [Ca2+]cyt associated with stomatal closure. They do not, however, exclude a contribution of Ca2+ influx from the apoplast
The Evolution of Calcium-Based Signalling in Plants
The calcium-based intracellular signalling system is used ubiquitously to couple extracellular stimuli to their characteristic intracellular responses. It is becoming clear from genomic and physiological investigations that while the basic elements in the toolkit are common between plants and animals, evolution has acted in such a way that, in plants, some components have diversified with respect to their animal counterparts, while others have either been lost or have never evolved in the plant lineages. In comparison with animals, in plants there appears to have been a loss of diversity in calcium-influx mechanisms at the plasma membrane. However, the evolution of the calcium-storing vacuole may provide plants with additional possibilities for regulating calcium influx into the cytosol. Among the proteins that are involved in sensing and responding to increases in calcium, plants possess specific decoder proteins that are absent from the animal lineage. In seeking to understand the selection pressures that shaped the plant calcium-signalling toolkit, we consider the evolution of fast electrical signalling. We also note that, in contrast to animals, plants apparently do not make extensive use of cyclic-nucleotide-based signalling. It is possible that reliance on a single intracellular second-messenger-based system, coupled with the requirement to adapt to changing environmental conditions, has helped to define the diversity of components found in the extant plant calcium-signalling toolkit
Three-Body approach to the K^- d Scattering Length in Particle Basis
We report on the first calculation of the scattering length A_{K^-d} based on
a relativistic three-body approach where the two-body input amplitudes coupled
to the Kbar N channels have been obtained with the chiral SU(3) constraint, but
with isospin symmetry breaking effects taken into account. Results are compared
with a recent calculation applying a similar set of two-body amplitudes,based
on the fixed center approximation, considered as a good approximation for a
loosely bound target, and for which we find significant deviations from the
exact three-body results. Effects of the hyperon-nucleon interaction, and
deuteron -wave component are also evaluated.Comment: 5 pages, Submitted to Phys. Rev.
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