300 research outputs found
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Fit for planning? An evaluation of the application of development viability appraisal models in the UK planning system
The aim of this paper is to critically examine the application of development appraisal to viability assessment in the planning system. This evaluation is of development appraisal models in general and also their use in particular applications associated with estimating planning obligation capacity. The paper is organised into four themes:
Ā· The context and conceptual basis for development viability appraisal
Ā· A review of development viability appraisal methods
Ā· A discussion of selected key inputs into a development viability appraisal
Ā· A discussion of the applications of development viability appraisals in the planning system
It is assumed that readers are familiar with the basic models and information needs of development viability appraisal rather than at the cutting edge of practice and/or academ
The Biogeochemistry of iron, zinc and cobalt in the Atlantic Ocean: the Atlantic Meridional Transect and UK GEOTRACES sections
Between 40 % and 50 % of the Earthās primary production occurs in marine environments, primarily by phytoplankton. The trace metal micronutrients iron, zinc and cobalt are known to exert a significant biological control on phytoplankton productivity by serving as essential active centres in enzymatic processes such as inorganic carbon, nitrogen and phosphorus acquisition. The distributions and biogeochemistries of iron, zinc and cobalt therefore, have the potential to impact upon the global carbon cycle and hence climate. This research involves investigations into the biogeochemical cycling of iron, zinc and cobalt in the Atlantic Ocean.
Iron measurements were conducted during October and November 2009 to determine the distribution and biogeochemistry of iron in the upper water column of the Atlantic Ocean along an Atlantic Meridional Transect (AMT-19). In addition, deck board incubation experiments were performed to establish the role of iron in controlling rates of di-nitrogen (N2) fixation in the North Atlantic. The distribution patterns and biogeochemistries of iron, zinc and cobalt in the South Atlantic at 40Ā° S were determined during the UK GEOTRACES Section GA10 cruises of October 2010 and December 2011 to January 2012.
Iron distributions in North Atlantic surface waters were primarily controlled by the transport and deposition of atmospheric dust particles. In the North Atlantic, elevated surface dissolved iron concentrations (0.50 - 1.65 nM) were associated with wet and dry deposition of Saharan dust between 4 and 29Ā° N. To the south of 4Ā° N, surface dissolved iron concentrations were markedly reduced (0.14 nM) indicating that high precipitation rates in the Inter-Tropical Convergence Zone (4 - 10Ā° N) formed a barrier to the large-scale transport of Saharan dust particles, thus iron, to the South Atlantic. Here, the low surface dissolved iron concentrations were balanced by a total dissolvable iron flux out of the surface mixed layer (3.2 Āµmol m-2 y-1) that was comparable to atmospheric input estimates. Nitrogen fixation rates in the North Atlantic were highest (0.3 ā 1.1 nmol L-1 d-1) where surface dissolved iron concentrations were elevated (1.02 nM) and decreased with increasing latitude as iron decreased. Hence, iron variability in the North Atlantic was sufficient to influence nitrogen fixation over a large spatial scale.
In the South Atlantic Ocean at 40Ā° S, the vertical and horizontal distributions of dissolved zinc and cobalt showed distinct gradients associated with the water masses present. Zinc concentrations ranged from 15 pM in open ocean surface waters to 8 nM in Antarctic Bottom Waters, whilst cobalt ranged from 2 pM to 80 pM in intermediate waters and was scavenged in deeper waters. Growth limiting mixed layer zinc concentrations resulted from the lack of a direct return path for zinc to the South Atlantic pycnocline with Sub-Antarctic Mode Water. Low zinc in this return path was identified by a linear correlation between zinc and soluble reactive phosphorus that showed a kink at ~ 500 m, much deeper than that observed in other oceanographic regimes. A seasonal study in the Southeast Atlantic revealed that the depletion of zinc over spring-summer periods resulted in an increase in the nutritional importance of cobalt and a shift towards phytoplankton with a cellular preference for cobalt over zinc and/or the ability to co-substitute these two trace metals at the molecular level.
These key findings demonstrate the physico-chemical and biological influences that interact to control the distributions and biogeochemistries of iron, zinc and cobalt across diverse oceanographic regimes of the Atlantic Ocean, provide the first examination of zinc and cobalt biogeochemistries along the productive 40Ā° S parallel and highlight the need for additional research in this region.National Environmental Research Counci
Fit for Planning? An Evaluation of the Application of Development Viability Appraisal Models in the UK Planning System
The aim of this paper is to critically examine the application of development appraisal to viability assessment in the planning system. This evaluation is of development appraisal models in general and also their use in particular applications associated with estimating planning obligation capacity. The paper is organised into four themes: Ā· The context and conceptual basis for development viability appraisal Ā· A review of development viability appraisal methods Ā· A discussion of selected key inputs into a development viability appraisal Ā· A discussion of the applications of development viability appraisals in the planning system. It is assumed that readers are familiar with the basic models and information needs of development viability appraisal rather than at the cutting edge of practice and/or academe.
A multi-channel system for use in cardiac electrophysiologic studies
The location of accessory pathways in Wolff-Parkinson-White syndrome patients is performed manually during open heart surgery at Groote Schuur Hospital, using a hand-held roving electrode. This manual procedure is slow and tedious, prolonging the operation and the time for which the patient remains on cardiac bypass. A multichannel electrogram acquisition and display system with a storage facility would significantly reduce the time taken and improve the reliability of locating the accessory pathways. Having considered a number of currently available cardiac mapping systems it was decided that a new system be developed for specific application within Groote Schuur Hospital. The main design goals of this system are to improve accuracy, increase reliability and enhance the speed of the entire mapping procedure with direct benefit to staff and patients. The system is based on an IBM compatible computer and allows for the acquisition of a maximum of thirty-two electrogram inputs. A typical configuration would acquire twenty epicardial, two references (one each from atrium and ventricle), one roving electrode and two surface lead signals. The epicardial signals are obtained from a custom-built electrode belt which is placed around the heart over the atrioventricular groove. The project includes the development of front-end hardware and software for processing, display and storage of electrogram signals. The relative activation times of the signals are displayed under software control in order to facilitate the location of any accessory pathway(s)
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Residual land values: measuring performance and investigating viability
Data on land values is important for market analysis and policy making. This research paper reviews sources of land prices and land value estimates in the UK, as well as recent attempts to create land price series in the US. It finds that there is little data available on land prices or values, particularly for commercial land uses.
A residual valuation model is used to estimate land values for hypothetical schemes in selected cities and regions. The residual land values are not market prices and do not capture the option value associated with real sites, but they give an indication of value for immediate development before planning obligations. Residual land values are analysed to determine whether changes in the viability of different land uses are driven primarily by costs, rents or pricing.
Land uses that have been modelled include residential apartments, offices, high street shops, industrial units and retail warehouses. Rents and yields were sourced from CBRE, apartment prices from the Office for National Statistics and construction costs from the Building Cost Information Service, with other inputs detailed in the report. Quarterly estimates of residual land values were produced from 1995 to 2016 for apartments and from 1997 to mid-2017 for the commercial land uses.
As expected, there is a major North/South divide across the country for some land uses analysed and, in some parts of the country for some uses, development would not be viable without intervention. Industrial schemes in the Midlands and North are a good example, but negative values also occur in some locations for apartments at the beginning and end of the analysis period.
Movements in residual land values through time are mainly driven by the largest input into the valuation model, development value. One reason for this is the lack of relative volatility in the construction costs estimates used for this analysis.
As a proportion of development value, residual land values have remained fairly stable across the different property types over the time period studied. The exception is during the 2007/2008 Financial Crisis when land values dropped to lower proportions across all the sectors. This indicates greater falls in land values than in the value of the associated developed asset, reinforcing the gearing effect and greater volatility of land values.
Land value forms the highest proportion of development value for high street retail and retail warehouses in relation to other uses. For most land uses, land values are also a higher share of total value in London relative to other regions and locations.
Where possible, the residual land values were benchmarked against existing land value data and indices. The results are variable across the sectors. For example, office residual land values in London increased at a greater rate than the Savills London Office Development Land Value Index in the aftermath of the Financial Crisis.
This research adds to existing knowledge of land values. It also increases the transparency of land
markets and could assist policy-making in relation to land value capture. It establishes a framework for continued recording of land value trends into the future, setting out the limitations of the approach. Finally, it invites discussion on the suitability of this framework for the creation of a development land value series for the UK
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Performance metrics and required returns for UK real estate development schemes
Real estate development has received less scrutiny than real estate investment in terms of appraisal practices and performance measurement. This is despite the inherent uncertainty and financial risks associated with development as an activity. We investigate market practices regarding performance metrics and return expectations both for residential and commercial real estate development in the UK, exploring what is considered as an appropriate return and how this varies according to type and duration of scheme, and method of appraisal used. After examining the literature and the information available on ex-post returns from development activity, results from a survey of real estate developers are reported, supplemented by findings from interviews. The results suggest that the use of traditional residual valuation techniques dominates discounted cash flow models when appraising development projects, particularly among residential developers, while profit-on-cost and profit-on-value are the most popular metrics for quantifying required returns. Unlike NPV or IRR, these metrics do not account for the timing of cash flows, raising questions about the robustness of appraisals in this sector. Such metrics might suffice if required profits are adjusted in ways that are consistent with scheme duration and risks, but it is unclear that this is currently the case.
Keywords
Development; Housebuilding; Profit Measures; Real Estate Appraisal; Required Return
Coffee and Caffeine Ingestion Have Little Effect on Repeated Sprint Cycling in Relatively Untrained Males
The present study investigated the effect of ingesting caffeine-dose-matched anhydrous caffeine or coffee on the performance of repeated sprints. Twelve recreationally active males (mean Ā± SD age: 22 Ā± 2 years, height: 1.78 Ā± 0.07 m, body mass: 81 Ā± 16 kg) completed eighteen 4 s sprints with 116 s recovery on a cycle ergometer on four separate occasions in a double-blind, randomised, counterbalanced crossover design. Participants ingested either 3 mgĀ·kgā1 of caffeine (CAF), 0.09 gĀ·kgā1 coffee, which provided 3 mgĀ·kgā1 of caffeine (COF), a taste-matched placebo beverage (PLA), or a control condition (CON) 45 min prior to commencing the exercise protocol. Peak and mean power output and rating of perceived exertion (RPE) were recorded for each sprint. There were no significant differences in peak power output (CAF: 949 Ā± 199 W, COF: 949 Ā± 174 W, PLA: 971 Ā± 149 W and CON: 975 Ā± 170 W; p = 0.872; Ī· P 2 = 0.02) or mean power output (CAF: 873 Ā± 172 W, COF: 862 Ā± 44 W, PLA: 887 Ā± 119 W and CON: 892 Ā± 143 W; p = 0.819; Ī· P 2 = 0.03) between experimental conditions. Mean RPE was similar for all trials (CAF: 11 Ā± 2, COF: 11 Ā± 2, PLA: 11 Ā± 2 and CON: 11 Ā± 2; p = 0.927; Ī· P 2 = 0.01). Neither the ingestion of COF or CAF improved repeated sprint cycling performance in relatively untrained males
Low tropical diversity during the adaptive radiation of early land plants.
The latitudinal biodiversity gradient, with tropical regions acting as 'evolutionary cradles', is a cornerstone of current biogeographical and ecological theory1. In the modern world floral biodiversity and biomass are overwhelmingly concentrated in the tropics, and it is often assumed that the tropics were evolutionary cradles throughout land plant evolutionary history. For example, the origination and diversification of angiosperms is believed to have taken place in the Cretaceous tropics2 and modern gymnosperms in the Permian tropics3. Here, we show that during the first major diversification of land plants, in the Late Silurian-Early Devonian, land plant biodiversity was much lower at the equator compared to medium-high southern latitudes. Throughout this crucial interval of plant evolution, tropical vegetation remained depauperate and of very low taxonomic biodiversity, although with similar morphological disparity to the more diverse higher latitude floras. Possible explanations for this low tropical floral biodiversity include palaeocontinental configuration or adverse palaeotropical environmental conditions. We discount the possibility that it was simply a fortuitous feature of the biogeographical spread of the earliest vascular land plants.National Geographi
Intrastriatal convection-enhanced delivery results in widespread perivascular distribution in a pre-clinical model
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