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Learning across business sectors: knowledge sharing between aerospace and construction
This report addresses the extent that managerial practices can be shared between the aerospace and construction sectors. Current recipes for learning from other industries tend to be oversimplistic and often fail to recognise the embedded and contextual nature of managerial knowledge. Knowledge sharing between business sectors is best understood as an essential source of innovation. The process of comparison challenges assumptions and better equips managers to cope with future change. Comparisons between the aerospace and construction sectors are especially useful because they are so different. The two sectors differ hugely in terms of their institutional context, structure and technological intensity. The aerospace sector has experienced extensive consolidation and is dominated by a small number of global companies. Aerospace companies operate within complex networks of global interdependency such that collaborative working is a commercial imperative. In contrast, the construction sector remains highly fragmented and is characterised by a continued reliance on small firms. The vast majority of construction firms compete within localised markets that are too often characterised by opportunistic behaviour.
Comparing construction to aerospace highlights the unique characteristics of both sectors and helps explain how managerial practices are mediated by context. Detailed comparisons between the two sectors are made in a range of areas and guidance is provided for the implementation of knowledge sharing strategies within and across organisations. The commonly accepted notion of ‘best practice’ is exposed as a myth. Indeed, universal models of best practice can be detrimental to performance by deflecting from the need to adapt continuously to changing circumstances. Competitiveness in the construction sector too often rests on efficiency in managing contracts, with a particular emphasis on the allocation of risk. Innovation in construction tends to be problem-driven and is rarely shared from project to project. In aerospace, the dominant model of competitiveness means that firms have little choice other than to invest in continuous innovation, despite difficult trading conditions. Research and development (R&D) expenditure in aerospace continues to rise as a percentage of turnovers. A sustained capacity for innovation within the aerospace sector depends crucially upon stability and continuity of work. In the construction sector, the emergence of the ‘hollowed-out’ firm has undermined the industry’s capacity for innovation. Integrated procurement contexts such as prime contracting in construction potentially provide a more supportive climate for an innovation-based model of competitiveness. However, investment in new ways of working depends upon a shift in thinking not only amongst construction contractors, but also amongst the industry’s major clients
High-to-low CO2 acclimation reveals plasticity of the photorespiratory pathway and indicates regulatory links to cellular metabolism of Arabidopsis
Background: Photorespiratory carbon metabolism was long considered as an essentially closed and nonregulated pathway with little interaction to other metabolic routes except nitrogen metabolism and respiration. Most mutants of this pathway cannot survive in ambient air and require CO 2-enriched air for normal growth. Several studies indicate that this CO 2 requirement is very different for individual mutants, suggesting a higher plasticity and more interaction of photorespiratory metabolism as generally thought. To understand this better, we examined a variety of high- and low-level parameters at 1% CO 2 and their alteration during acclimation of wild-type plants and selected photorespiratory mutants to ambient air. Methodology and Principal Findings: The wild type and four photorespiratory mutants of Arabidopsis thaliana (Arabidopsis) were grown to a defined stadium at 1% CO 2 and then transferred to normal air (0.038% CO 2). All other conditions remained unchanged. This approach allowed unbiased side-by-side monitoring of acclimation processes on several levels. For all lines, diel (24 h) leaf growth, photosynthetic gas exchange, and PSII fluorescence were monitored. Metabolite profiling was performed for the wild type and two mutants. During acclimation, considerable variation between the individual genotypes was detected in many of the examined parameters, which correlated with the position of the impaired reaction in the photorespiratory pathway. Conclusions: Photorespiratory carbon metabolism does not operate as a fully closed pathway. Acclimation from high to low CO 2 was typically steady and consistent for a number of features over several days, but we also found unexpected short-term events, such as an intermittent very massive rise of glycine levels after transition of one particular mutant to ambient air. We conclude that photorespiration is possibly exposed to redox regulation beyond known substrate-level effects. Additionally, our data support the view that 2-phosphoglycolate could be a key regulator of photosynthetic-photorespiratory metabolism as a whole. © 2012 Timm et al
Decreased expression of plastidial adenylate kinase in potato tubers results in an enhanced rate of respiration and a stimulation of starch synthesis that is attributable to post-translational redox-activation of ADP-glucose pyrophosphorylase
Adenine nucleotides are of general importance for many aspects of cell function, but their role in the regulation of biosynthetic processes is still unclear. It was previously reported that decreased expression of plastidial adenylate kinase, catalysing the interconversion of ATP and AMP to ADP, leads to increased adenylate pools and starch content in transgenic potato tubers. However, the underlying mechanisms were not elucidated. Here, it is shown that decreased expression of plastidial adenylate kinase in growing tubers leads to increased rates of respiratory oxygen consumption and increased carbon fluxes into starch. Increased rates of starch synthesis were accompanied by post-translational redox-activation of ADP-glucose pyrophosphorylase (AGPase), catalysing the key regulatory step of starch synthesis in the plastid, while there were no substantial changes in metabolic intermediates or sugar levels. A similar increase in post-translational redox-activation of AGPase was found after supplying adenine to wild-type potato tuber discs to increase adenine nucleotide levels. Results provide first evidence for a link between redox-activation of AGPase and adenine nucleotide levels in plants
Intra- and extra-cellular excretion of carboxylates
Carboxylates, such as malate and citrate, are widely acknowledged to have a central role in plant metabolism. They are involved in the production of energy and its storage as well as contributing to the cellular osmolyte pool and participating in the regulation of cellular pH. As we discuss here, recent research has demonstrated the functional importance of carboxylate excretion into the soil, apoplast and vacuole, particular with respect to the regulation of stomatal and root function
Integrative Comparative Analyses of Transcript and Metabolite Profiles from Pepper and Tomato Ripening and Development Stages Uncovers Species-Specific Patterns of Network Regulatory Behavior
Integrative comparative analyses of transcript and metabolite levels from climacteric and nonclimacteric fruits can be employed to unravel the similarities and differences of the underlying regulatory processes. To this end, we conducted combined gas chromatography-mass spectrometry and heterologous microarray hybridization assays in tomato (Solanum lycopersicum; climacteric) and pepper (Capsicum chilense; nonclimacteric) fruits across development and ripening. Computational methods from multivariate and network-based analyses successfully revealed the difference between the covariance structures of the integrated data sets. Moreover, our results suggest that both fruits have similar ethylene-mediated signaling components; however, their regulation is different and may reflect altered ethylene sensitivity or regulators other than ethylene in pepper. Genes involved in ethylene biosynthesis were not induced in pepper fruits. Nevertheless, genes downstream of ethylene perception such as cell wall metabolism genes, carotenoid biosynthesis genes, and the never-ripe receptor were clearly induced in pepper as in tomato fruit. While signaling sensitivity or actual signals may differ between climacteric and nonclimacteric fruit, the evidence described here suggests that activation of a common set of ripening genes influences metabolic traits. Also, a coordinate regulation of transcripts and the accumulation of key organic acids, including malate, citrate, dehydroascorbate, and threonate, in pepper fruit were observed. Therefore, the integrated analysis allows us to uncover additional information for the comprehensive understanding of biological events relevant to metabolic regulation during climacteric and nonclimacteric fruit development
Alteration of the interconversion of pyruvate and malate in the plastid or cytosol of ripening tomato fruit invokes diverse consequences on sugar but similar effects on cellular organic Acid, metabolism, and transitory starch accumulation
The aim of this work was to investigate the effect of decreased cytosolic phosphoenolpyruvate carboxykinase (PEPCK) and plastidic NADP-dependent malic enzyme (NADP-ME) on tomato (Solanum lycopersicum) ripening. Transgenic tomato plants with strongly reduced levels of PEPCK and plastidic NADP-ME were generated by RNA interference gene silencing under the control of a ripening-specific E8 promoter. While these genetic modifications had relatively little effect on the total fruit yield and size, they had strong effects in fruit metabolism. Both transformants were characterized by lower levels of starch at breaker stage. Analysis of the activation state of ADP-glucose pyrophosphorylase correlated with the decrease of starch in both transformats, which suggest that is due to an altered cellular redox status. Moreover, metabolic profiling and feeding experiments involving positional labelled glucoses of fruits lacking in plastidic NADP-malic enzyme and cytosolic PEPCK activities revealed differential changes in overall respiration rates and tricarboxylic acid (TCA) cycle flux. Inactivation of cytosolic PEPCK affected the respiration rate which suggests that excess of oxaloacetate OAA is converted to aspartate and reintroduced in the TCA via 2-oxoglutarate/glutamate. On the other hand, the plastidic NADP-malic enzyme antisense lines were characterized by no changes in respiration rates and TCA cycle flux and together with an increase of pyruvate kinase and phosphoenolpyruvate carboxylase activities indicates that pyruvate is supply through these enzymes to the TCA cycle. These results are discussed in the context of current models of the importance of malate during tomato fruit ripening
Reddenings of FGK supergiants and classical Cepheids from spectroscopic data
Accurate and homogeneous atmospheric parameters (Teff, log (g), Vt, [Fe/H])
are derived for 74 FGK non-variable supergiants from high-resolution, high
signal-to-noise ratio, echelle spectra. Extremely high precision for the
inferred effective temperatures (10-40 K) is achieved by using the line-depth
ratio method. The new data are combined with atmospheric values for 164
classical Cepheids, observed at 675 different pulsation phases, taken from our
previously published studies. The derived values are correlated with unreddened
B-V colours compiled from the literature for the investigated stars in order to
obtain an empirical relationship of the form: (B-V)o = 57.984 - 10.3587(log
Teff)^2 + 1.67572(log Teff)^3 - 3.356(log (g)) + 0.0321(Vt) + 0.2615[Fe/H] +
0.8833((log (g))(log Teff)). The expression is used to estimate colour excesses
E(B-V) for individual supergiants and classical Cepheids, with a precision of
+-0.05 mag. for supergiants and Cepheids with n=1-2 spectra, reaching +-0.025
mag. for Cepheids with n>2 spectra, matching uncertainties for the most
sophisticated photometric techniques. The reddening scale is also a close match
to the system of space reddenings for Cepheids. The application range is for
spectral types F0--K0 and luminosity classes I and II.Comment: accepted for publication (MNRAS
Classical Cepheid Pulsation Models: IX. New Input Physics
We constructed several sequences of classical Cepheid envelope models at
solar chemical composition () to investigate the dependence of
the pulsation properties predicted by linear and nonlinear hydrodynamical
models on input physics. To study the dependence on the equation of state (EOS)
we performed several numerical experiments by using the simplified analytical
EOS originally developed by Stellingwerf and the recent analytical EOS
developed by Irwin. Current findings suggest that the pulsation amplitudes as
well as the topology of the instability strip marginally depend on the adopted
EOS.
We also investigated the dependence of observables predicted by theoretical
models on the mass-luminosity (ML) relation and on the spatial resolution
across the Hydrogen and the Helium partial ionization regions. We found that
nonlinear models are marginally affected by these physical and numerical
assumptions. In particular, the difference between new and old models in the
location as well as in the temperature width of the instability strip is on
average smaller than 200 K. However, the spatial resolution somehow affects the
pulsation properties. The new fine models predict a period at the center of the
Hertzsprung Progression (9.84 days) that reasonably agree with
empirical data based on light curves ( days;
\citealt{mbm92}) and on radial velocity curves ( days;
\citealt{mall00}), and improve previous predictions by Bono, Castellani, and
Marconi (2000, hereinafter BCM00).Comment: 35 pages, 7 figures. Accepted for publication in the Astrophysical
Journa
Understanding policy and change: using a political economy analysis framework
The gap between the intent and the impact of policy for construction in the UK has been well established both in academic literature and in public discourse, contributing to repeated calls for transformation of the industry. The apparent failure of policy was investigated, taking policy at sector level as the unit of analysis. The objective was to both generate insight into the policy process and to establish a theoretical framework. Anticipating that the use of language, and the conflicting meanings attached to it by individual actors, is critical, an interpretive, abductive, research design was adopted. Twenty semi-structured interviews were carried out with a cross-section of industry actors. Methods of political economy analysis, used in other contexts, were adopted as the starting point for abduction. Analysis revealed flawed assumptions amongst stakeholders regarding the extent of the agency of central government in implementing change across such a heterogeneous and loosely coupled sector. Political economy analysis shows the impact of structural and institutional features on the sector in a systemic and holistic way, providing a template and visual model which supports collaborative and reflexive working, and forming a foundation for further research into policy for construction both in the UK and elsewhere
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