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The general packet radio service (GPRS) has been developed to allow packet data to be transported efficiently over an existing circuit-switched radio network, such as GSM. The main application of GPRS are in transporting Internet protocol (IP) datagrams from web servers (for telemetry or for mobile Internet browsers). Four GPRS baseband coding schemes are defined to offer a trade-off in requested data rates versus propagation channel conditions. However, data rates in the order of > 100 kbits/s are only achievable if the simplest coding scheme is used (CS-4) which offers little error detection and correction (EDC) (requiring excellent SNR) and the receiver hardware is capable of full duplex which is not currently available in the consumer market. A simple EDC scheme to improve the GPRS block error rate (BLER) performance is presented, particularly for CS-4, however gains in other coding schemes are seen. For every GPRS radio block that is corrected by the EDC scheme, the block does not need to be retransmitted releasing bandwidth in the channel and improving the user's application data rate. As GPRS requires intensive processing in the baseband, a viable field programmable gate array (FPGA) solution is presented in this paper.

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The ability to resist or avoid natural enemy attack is a critically important insect life history trait, yet little is understood of how these traits may be affected by temperature. This study investigated how different genotypes of the pea aphid Acyrthosiphon pisum Harris, a pest of leguminous crops, varied in resistance to three different natural enemies (a fungal pathogen, two species of parasitoid wasp and a coccinellid beetle), and whether expression of resistance was influenced by temperature. Substantial clonal variation in resistance to the three natural enemies was found. Temperature influenced the number of aphids succumbing to the fungal pathogen Erynia neoaphidis Remaudiere & Hermebert, with resistance increasing at higher temperatures (18 vs. 28degreesC). A temperature difference of 5degreesC (18 vs. 23degreesC) did not affect the ability of A. pisum to resist attack by the parasitoids Aphidius ervi Haliday and A. eadyi Stary Gonzalez & Hall. Escape behaviour from foraging coccinellid beetles (Hippodamia convergens Guerin-Meneville) was not directly influenced by aphid clone or temperature (16 vs. 21degreesC). However, there were significant interactions between clone and temperature (while most clones did not respond to temperature, one was less likely to escape at 16degreesC), and between aphid clone and ladybird presence (some clones showed greater changes in escape behaviour in response to the presence of foraging coccinellids than others). Therefore, while larger temperature differences may alter interactions between Acyrthosiphon pisum and an entomopathogen, there is little evidence to suggest that smaller changes in temperature will alter pea aphid-natural enemy interactions.

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This invention relates to the manufacture of coated substrates, and particularly, but not exclusively, to the deposition of multi-layer coatings in the manufacture of interference filters consisting of multiple thin films. An object of the invention is to allow accurate control of the deposition of a succession of layers having good uniformity, for example during the manufacture by vacuum evaporation of multilayer interference filters for use with infrared radiation of particularly long wavelength, using a method which is self calibrating and which avoids the repetitive use of individual control layers.

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Purpose – Innovation in facilities management (FM) is a complex process as FM is a diverse discipline. This paper aims to use innovation trajectories to explore this complex process through the introduction of a technology innovation in two FM services of security and workspace management. It also aims to consider the discourse of individuals within their trajectory to understand their positions toward the innovation. Design/methodology/approach – A two-year case study was conducted and it was based in an in-house FM department that was part of a financial institution. The specific methods used for the paper were semi-structured interviews with key participants of the project. Critical discourse analysis was used to examine the data. Findings – Individuals who were involved in introducing the technology to the FM department were both internal and external to FM as innovation in FM does not happen in isolation to the organisation. Innovation trajectories were often intertwined or occurred simultaneously during the process of a project which sometimes resulted in conflict. Tensions within the discourse of ownership of the project were particularly apparent as this discourse had a power dimension in driving the project through to implementation. Research limitations/implications – The research is limited by being a single case study so it is not possible to generalise findings but the findings may have resonances with other organisations. Originality/value – The paper presents an original idea about how to understand innovation processes in FM services.

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The role of the academic in the built environment seems generally to be not well understood or articulated. While this problem is not unique to our field, there are plenty of examples in a wide range of academic disciplines where the academic role has been fully articulated. But built environment academics have tended not to look beyond their own literature and their own vocational context in trying to give meaning to their academic work. The purpose of this keynote presentation is to explore the context of academic work generally and the connections between education, research and practice in the built environment, specifically. By drawing on ideas from the sociology of the professions, the role of universities, and the fundamentals of social science research, a case is made that helps to explain the kind of problems that routinely obstruct academic progress in our field. This discussion reveals that while there are likely to be great weaknesses in much of what is published and taught in the built environment, it is not too great a stretch to provide a more robust understanding and a good basis for developing our field in a way that would enable us collectively to make a major contribution to theory-building, theory-testing and to make a good stab at tackling some of the problems facing society at large. There is no reason to disregard the fundamental academic disciplines that underpin our knowledge of the built environment. If we contextualise our work in these more fundamental disciplines, there is every reason to think that we can have a much greater impact that we have experienced to date.

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OBJECTIVE: The present study was carried out to investigate effects of meals, rich in either saturated fatty acids (SFA), or n-6 or n-3 fatty acids, on postprandial plasma lipid and hormone concentrations as well as post-heparin plasma lipoprotein lipase (LPL) activity. DESIGN: The study was a randomized single-blind study comparing responses to three test meals. SETTING: The volunteers attended the Clinical Investigation Unit of the Royal Surrey County Hospital on three separate occasions in order to consume the meals. SUBJECTS: Twelve male volunteers with an average age of 22.5 +/- 1.4 years (mean +/- SD), were selected from the University of Surrey student population; one subject dropped out of the study because he found the test meal unpalatable. INTERVENTIONS: Three meals were given in the early evening and postprandial responses were followed overnight for 11h. The oils used to prepare each of the three test meals were: a mixed oil rich in saturated fatty acids (SFA) which mimicked the fatty acid composition of the current UK diet, corn oil, rich in n-6 fatty acids and a fish oil concentrate (MaxEPA) rich in n-3 fatty acids. The oil under investigation (40 g) was incorporated into the test meals which were otherwise identical [208 g carbohydrates, 35 g protein, 5.65 MJ (1350 kcal) energy]. Postprandial plasma triacylglycerol (TAG), gastric inhibitory polypeptide (GIP), and insulin responses, as well as post-heparin LPL activity (measured at 12 h postprandially only) were investigated. RESULTS: Fatty acids of the n-3 series significantly reduced plasma TAG responses compared to the mixed oil meal (P < 0.05) and increased post-heparin LPL activity 15 min after the injection of heparin (P < 0.01). A biphasic response was observed in TAG, with peak responses occurring at 1 h and between 3-7 h postprandially. GIP and insulin showed similar responses to the three test meals and no significant differences were observed. CONCLUSION: We conclude that fish oils can decrease postprandial plasma TAG levels partly through an increase in post-heparin LPL activity, which however, is not due to increased GIP or insulin concentrations.

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It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The sub-continent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite-derived rainfall data from the Microwave Infrared Rainfall Algorithm (MIRA). This dataset covers the period from 1993 to 2002 and the whole of southern Africa at a spatial resolution of 0.1° longitude/latitude. This paper concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of present-day rainfall variability over southern Africa and is not intended to discuss possible future changes in climate as these have been documented elsewhere. Simulations of current climate from the UKMeteorological Office Hadley Centre’s climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. Secondly, the ability of the model to reproduce daily rainfall extremes is assessed, again by a comparison with extremes from the MIRA dataset. The results suggest that the model reproduces the number and spatial distribution of rainfall extremes with some accuracy, but that mean rainfall and rainfall variability is underestimated (over-estimated) over wet (dry) regions of southern Africa.

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Another Proof of the Preceding Theory was produced as part of a residency run by Artists in Archeology in conjunction with the Stonehenge Riverside project. The film explores the relationship between science, work and ritual, imagining archaeology as a future cult. As two robed disciples stray off from the dig, they are drawn to the drone of the stones and proceed to play the henge like a gigantic Theremin. Just as a Theremin is played with the hand interfering in an electric circuit and producing sound without contact, so the stones respond to the choreographed bodily proximity. Finally, one of the two continues alone to the avenue at Avebury, where the magnetic pull of the stones reaches its climax. Shot on VHS, the film features a score by Zuzushi Monkey, with percussion and theremin sounds mirroring the action. The performers are mostly artists and archeologists from the art and archaeology teams. The archeologists were encouraged to perform their normal work in the robes, in an attempt to explore the meeting points of science and ritual and interrogate our relationship to an ultimately unknowable prehistoric past where activities we do not understand are relegated to the realm of religion. Stonehenge has unique acoustic properties, it’s large sarsen stones are finely worked on the inside, left rough on the outside, intensifying sound waves within the inner horseshoe, but since their real use, having been built over centuries, remains ambiguous, the film proposes that our attempts to decode them may themselves become encoded in their cumulative meaning for future researchers.

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This paper addresses the commercial leases policy issue of how to deal with small business tenants. The UK has adopted a voluntary solution to commercial lease reform by using Codes of Practice which is in contrast to the legislative approach adopted by Australia to attempt to solve its perceived problems with small business retail tenancies. The major aim of the research was to examine the perceptions of the effectiveness of the legislation in Australia and discuss any implications for the UK policy debate but the results of the research also raise questions for the Australian regime. The research used a combination of literature and legislation review and a semi structured interview survey to investigate the policy aims and objectives of Australian Federal and State Governments, identify the nature and scope of the Australian legislation and examine perceptions of effectiveness of the legislation in informing small business tenants. The situation is complicated in Australia due to leases being a State rather than Federal responsibility therefore the main fieldwork was carried out in one case study State, Victoria. The paper concludes that some aspects of the Australian system can inform the UK policy debate including mandatory information provision at the commencement of negotiations and the use of lease registrars/commissioners. However, there are a number of issues that the Australian legislation does not appear to have successfully addressed including the difficulties of legislating across partial segments of the commercial property market and the collection of data for enforcement purposes.

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In negotiating commercial leases, many landlords and tenants employ property agents (brokers) to act on their behalf; typically these people are chartered surveyors. The aim of this paper is to explore the role that these brokers play in the shaping of commercial leases in the context of the current debate in the UK on upward only rent reviews. This role can be described using agency theory and the theories of professionalism. These provide expectations of behaviour which show inherent tensions between the role of agent and professional, particularly regarding the use of knowledge, autonomy and the obligation to the public interest. The parties to eleven recent lease transactions were interviewed to see if the brokers conformed to the expectations of agency theory or professionalism. Brokers that acted for industrial and office tenants behaved as professionals in using their expertise to determine lease structures. However, those acting for landlords and retail tenants simply followed instructions and behaved as conduits for their clients, a role more usually associated with that of an agent within the principal-agent relationship. None of the landlords’ brokers saw themselves as having responsibilities beyond their clients and so they were not promoting the discussion of alternatives to the UORR. The evidence from these case studies suggests that agents are not professionals; to behave entirely as an agent is to contradict the essential characteristics of a professional. While brokers cannot be held entirely responsible for the lack of movement on the UORR, by adopting predominantly agent roles then they must take some of the blame. However, behind this may be a much larger issue that needs to be explored; the institutional pressures that lead to professionals behaving in this way.

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In this paper we undertake a preliminary assessment of the regional planning and development implications of BAA Stansted Airport’s planning permission to grow to 25 million passengers per annum (mppa) by 2010. Our concern is not simply to consider the overall growth of the airport on the airport site itself but the nature and type of growth both on- and off-site. In this document we focus on the submitted planning permission documents and test them. The methodology we employed was to draw on published and unpublished numerical estimates of the airport’s growth – particularly including estimates produced by the airport owner, BAA, and their economic and planning consultants DTZ Pieda - and critically, and systematically analyse their figures. We adopted this approach because unless the figures which were employed in the initial calculations were correct then all of the subsequent projections which flow from them - and the polices which could then be based on them – could be flawed. The analysis is divided into two parts – firstly, are the growth forecasts correct?; and secondly, what do these forecasts actually mean in developmental terms? In effect, what we have done is to produce a critique of the existing body of evidence by questioning underpinning assumptions and then draw some preliminary conclusions for the region based on this analysis. A major focus of this report has been analyse the figures involved in the planning application to expand Stansted to 25mppa. Ironically, one of our key findings, that the local impact of Stansted’s proposed expansion in employment terms might well be less than was originally thought, might make it easier to gain the acceptance of the relevant local authorities involved to allow the development to take place. Our main overall findings are that the BAA projections over-estimate the local employment impact of the airport’s proposed growth and under-estimate its potential regional ‘transportation’ employment effect. These two findings are, of course, related to each other in important ways, and we also feel that they have potentially significant medium and long-term economic, competitiveness and planning policy implications for the East of England region

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It has been suggested that sources of P could be used to remediate metal-contaminated soil. The toxicity of four potential P sources, potassium hydrogen phosphate (PHP), triple superphosphate (TSP), rock phosphate (RP) and raw bone meal (RBM) to Eisenia fetida was determined. The concentration of P that is statistically likely to kill 50% of the population (LC50) for PHP, TSP and RBM was determined in OECD acute toxicity tests. 14 day LC50s expressed as bulk P concentration lay in the range 3319–4272 mg kg−1 for PHP, 3107–3590 mg kg−1 for TSP and 1782–2196 mg kg−1 for RBM (ranges present the 95% confidence intervals). For PHP and TSP mortality was significantly impacted by the electrical conductivity of the treated soils. No consistent relationship existed between mortality and electrical conductivity, soil pH and available (Olsen) P across the PHP, TSP and RBM amendment types. In RP toxicity tests mortality was low and it was not possible to determine a LC50 value. Incineration of bone meal at temperatures between 200 and 300 ◦C, pre-washing the bone meal, co-amendment with 5% green waste compost and delaying introduction of earthworms after bone meal amendments by 21 days or more led to significant reductions in the bone meal toxicity. These results are consistent with the toxicity being associated with the release and/or degradation of a soluble organic component present in raw bone meal. Bone meal can be used as an earthworm-friendly remedial amendment in metal-contaminated soils but initial additions may have a negative effect on any earthworms surviving in the contaminated soil before the organic component in the bone meal degrades in the soil.

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The aim of this study was to test the impact of compost and Biochar, with or without earthworms, on the mobility and availability of metals, and on the growth of grass to re-vegetate contaminated soil from the Parys Mountain mining site, Anglesey. We also determined if the addition of earthworms compromises remediation efforts. In a laboratory experiment, contaminated soil (1343 mg Cu kg−1, 2511 mg Pb kg−1 and 262 mg Zn kg−1) was remediated with compost and/or Biochar. After 77 days Lumbricus terrestris L. earthworms were added to the treatment remediated with both compost and Biochar, and left for 28 days. L. terrestris was not able to survive in the Biochar, compost or unamended treatments. A germination and growth bioassay, using Agrostis capillaris (Common Bent) was then run on all treatments for 28 days. The combination of Biochar and compost decreased water soluble Cu (from 5.6 to 0.2 mg kg−1), Pb (0.17 to less than 0.007 mg kg−1) and Zn (3.3 to 0.05 mg kg−1) in the contaminated soil and increased the pH from 2.7 to 6.6. The addition of L. terrestris to this treatment had no effect on the concentration of the water soluble metals in the remediated soil. The compost was the only treatment that resulted in germination and growth of A. capillaris suitable for re-vegetation purposes. However, the combination of compost, Biochar (with or without L. terrestris) produced the lowest concentrations of Cu (8 mg kg−1) and Zn (36 mg kg−1) in the aboveground biomass, lower than the compost treatment (15 mgCu kg−1 and 126 mgZn kg−1). The addition of Biochar and compost both separately and as co-amendments was effective in reducing the mobility and availability of metals. The addition of L. terrestris did not re-mobilise previously sequestered metals.

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This paper builds upon previous research on currency bands, and provides a model for the Colombian peso. Stochastic differential equations are combined with information related to the Colombian currency band to estimate competing models of the behaviour of the Colombian peso within the limits of the currency band. The resulting moments of the density function for the simulated returns describe adequately most of the characteristics of the sample returns data. The factor included to account for the intra-marginal intervention performed to drive the rate towards the Central Parity accounts only for 6.5% of the daily change, which supports the argument that intervention, if performed by the Central Bank, it is not directed to push the currency towards the limits. Moreover, the credibility of the Colombian Central Bank, Banco de la República’s ability to defend the band seems low.

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Ecosystems consist of aboveground and belowground subsystems and the structure of their communities is known to change with distance. However, most of this knowledge originates from visible, aboveground components, whereas relatively little is known about how soil community structure varies with distance and if this variability depends on the group of organisms considered. In the present study, we analyzed 30 grasslands from three neighboring chalk hill ridges in southern UK to determine the effect of geographic distance (1e198 km) on the similarity of bacterial communities and of nematode communities in the soil. We found that for both groups, community similarity decayed with distance and that this spatial pattern was not related to changes either in plant community composition or soil chemistry. Site history may have contributed to the observed pattern in the case of nematodes, since the distance effect depended on the presence of different nematode taxa at one of the hill ridges. On the other hand, site-related differences in bacterial community composition alone could not explain the spatial turnover, suggesting that other factors, such as biotic gradients and local dispersal processes that we did not include in our analysis, may be involved in the observed pattern. We conclude that, independently of the variety of causal factors that may be involved, the decay in similarity with geographic distance is a characteristic feature of both communities of soil bacteria and nematodes.