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Her Majesty's Stationery Office (her + majesty_stationery_office)
Selected AbstractsDeveloping LHCb Grid software: experiences and advancesCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2007I. Stokes-Rees Abstract The LHCb Grid software has been used for two Physics Data Challenges, with the latter producing over 98 TB of data and consuming over 650 processor-years of computing power. This paper discusses the experience of developing a Grid infrastructure, interfacing to an existing Grid (LCG) and traditional computing centres simultaneously, running LHCb experiment software and jobs on the Grid, and the integration of a number of new technologies into the Grid infrastructure. Our experience and utilization of the following core technologies will be discussed: OGSI, XML-RPC, Grid services, LCG middleware and instant messaging. Specific attention will be given to analysing the behaviour of over 100,000 jobs executed through the LCG Grid environment, providing insight into the performance, failure modes and scheduling efficiency over a period of several months for a large computational Grid incorporating over 40 sites and thousands of nodes. © Crown copyright 2006. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Diagnosing and treating diabetic foot infectionsDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue S1 2004Benjamin A. Lipsky Abstract Foot infections are a common, complex and costly complication of diabetes. We have made considerable progress in establishing consensus definitions for defining infection. Similarly, we have learned much about the appropriate ways to diagnose both soft tissue and bone infections. Accompanying these advances have been improvements in our knowledge of the proper approaches to antibiotic (and surgical) therapy for diabetic foot infections. Furthermore, investigators have explored the value of various adjunctive therapies, especially granulocyte colony stimulating factors and hyperbaric oxygen, for improving outcomes. This paper presents a summary of a minisymposium on infection of the diabetic foot that was held at the fourth International Symposium on the Diabetic Foot, in Noordwijkerhout, The Netherlands. Crown copyright 2004. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] A comparison of spatial interpolation methods to estimate continuous wind speed surfaces using irregularly distributed data from England and WalesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2008W. Luo Abstract Seven methods of spatial interpolation were compared to determine their suitability for estimating daily mean wind speed surfaces, from data recorded at nearly 190 locations across England and Wales. The eventual purpose of producing such surfaces is to help estimate the daily spread of pathogens causing crop diseases as they move across regions. The interpolation techniques included four deterministic and three geostatistical methods. Quantitative assessment of the continuous surfaces showed that there was a large difference between the accuracy of the seven interpolation methods and that the geostatistical methods were superior to deterministic methods. Further analyses, testing the reliability of the results, showed that measurement accuracy, density, distribution and spatial variability had a substantial influence on the accuracy of the interpolation methods. Independent wind speed data from ten other dates were used to confirm the robustness of the best interpolation methods. © Crown copyright 2007. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Uncertainties in central England temperature 1878,2003 and some improvements to the maximum and minimum seriesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2005David Parker Abstract We assess the random and systematic uncertainties affecting the central England temperature (CET) record since 1878 on daily, monthly and annual time scales. The largest contribution to uncertainty in CET on all these time scales arises from areal sampling, followed for annual and monthly CET by thermometer calibration. For the daily series, random thermometer precision and screen errors are the second largest source of uncertainty. Annual CETs are least uncertain, whereas daily CETs are most uncertain. Despite the uncertainties in annual mean CET, the trend of 0.077 °C per decade since 1900 is significant at the 1% level. In an additional investigation, we detect biases in the published series of central England maximum and minimum temperatures, and implement systematic adjustments of up to ±0.2 °C to the values up to 1921 and up to ±0.1 °C to the values since 1980. These adjustments are of opposite sign in maximum and minimum temperature, so they do not affect mean CET, but they improve the homogeneity of the diurnal temperature range, which then shows little trend before 1980 and a reduced rising trend thereafter. The uncertainties in maximum and minimum temperature make the data inadequate for the task of establishing the magnitude of the recent increase of diurnal range. © Crown Copyright 2005. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] The development of a new set of long-term climate averages for the UKINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2005Matthew Perry Abstract Monthly and annual long-term average datasets of 13 climate variables are generated for the periods 1961,90 and 1971,2000 using a consistent analysis method. Values are produced for each station in the Met Office's observing network and for a rectangular grid of points covering the UK at a horizontal spacing of 1 km. The variables covered are mean, maximum, minimum, grass minimum and soil temperature, days of air and ground frost, precipitation, days with rain exceeding 0.2 and 1 mm, sunshine, and days with thunder and snow cover. Gaps in the monthly station data are filled with estimates obtained via regression relationships with a number of well-correlated neighbours, and long-term averages are then calculated for each site. Gridded datasets are created by inverse-distance-weighted interpolation of regression residuals obtained from the station averages. This method does not work well for days of frost, thunder and snow, so an alternative approach is used. This involves first producing a grid of values for each month from the available station data. The gridded long-term average datasets are then obtained by averaging the monthly grids. The errors associated with each stage in the process are assessed, including verification of the gridding stage by leaving out a set of stations. The estimation of missing values allows a dense network of stations to be used, and this, along with the range of independent variables used in the regression, allows detailed and accurate climate datasets and maps to be produced. The datasets have a range of applications, and the maps are freely available through the Met Office Website. © Crown Copyright 2005. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] The generation of monthly gridded datasets for a range of climatic variables over the UKINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2005Matthew Perry Abstract Monthly or annual 5 km × 5 km gridded datasets covering the UK are generated for the 1961,2000 period, for 36 climatic parameters. As well as the usual elements of temperature, rainfall, sunshine, cloud, wind speed, and pressure, derived temperature variables (such as growing-season length, heating degree days, and heat and cold wave durations) and further precipitation variables (such as rainfall intensity, maximum consecutive dry days, and days of snow, hail and thunder) are analysed. The analysis process uses geographical information system capabilities to combine multiple regression with inverse-distance-weighted interpolation. Geographic and topographic factors, such as easting and northing, terrain height and shape, and urban and coastal effects, are incorporated either through normalization with regard to the 1961,90 average climate, or as independent variables in the regression. Local variations are then incorporated through the spatial interpolation of regression residuals. For each of the climatic parameters, the choice of model is based on verification statistics produced by excluding a random set of stations from the analysis for a selection of months, and comparing the observed values with the estimated values at each point. This gives some insight into the significance, direction, and seasonality of factors affecting different climate elements. It also gives a measure of the accuracy of the method at predicting values between station locations. The datasets are being used for the verification of climate modelling scenarios and are available via the Internet. © Crown Copyright 2005. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Kojic acid reduces the cytotoxic effects of sulfur mustard on cultures containing human melanoma cells in vitroJOURNAL OF APPLIED TOXICOLOGY, Issue 6 2001C. N. Smith Abstract In vivo experiments have shown that melanocytes are more sensitive than keratinocytes to the cytotoxic effects of sulfur mustard when it is applied topically to pig skin.1 It has been hypothesized that this is caused by the uncoupling of the melanogenic pathway by depletion of cellular glutathione, resulting in the uncontrolled production of cytotoxic quinone free-radical species by tyrosinase.2. In the present study, the feasibility of blocking the melanogenic pathway as a means of reducing the cytotoxicity of sulfur mustard was evaluated using kojic acid. Kojic acid is a topically applied depigmenting agent that exerts its effect by acting as a slow-binding, competitive inhibitor of tyrosinase.3 Preincubation of G361 pigmented melanoma cells and mixed cultures of G361 cells and SVK keratinocytes with 2.5 mM kojic acid resulted in significant increases in the viability of these cultures as determined by neutral red (NR) and gentian violet (GV) dye binding assays for up to 48 h following exposure to 50 µM sulfur mustard. The highest levels of protection were seen in the G361 cultures, with a 26.8% increase in culture viability (NR assay) compared with the sulfur-mustard-only controls at 24 h. Preincubation of SVK cells alone with kojic acid resulted in lower increases in viability (2.5% at 24 h by the NR assay). Inhibition of the melanogenic pathway reduces the sensitivity of cultures containing pigment cells to sulfur mustard. © Crown copyright 2001. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] A major breakpoint cluster domain in murine radiation-induced acute myeloid leukemia,MOLECULAR CARCINOGENESIS, Issue 2 2002Rosemary Finnon Abstract Cytogenetic and molecular studies have provided evidence of the clustering of chromosome 2 deletion breakpoints in radiation-induced murine acute myeloid leukemia (AML). Moreover, clustering occurs in at least two fragile domains rich in telomere-like arrays. Here we describe a physical map of the distal breakpoint cluster and confirm the presence of inverted head-to-head telomeric sequence arrays. These potentially recombinogenic sequences were not, however, the direct focus for post-irradiation chromosome breakage in AML. Instead, the two arrays bordered a 2.5-kb sequence with properties expected of a nuclear matrix attachment region (MAR). The putative MAR co-localized in the fragile domain with genes important to the hemopoietic system (leukocyte tyrosine kinase, zinc finger protein 106, erythrocyte protein band 4.2, and ,2 -microglobulin (,2m)); the ,2m subdomain was a particular focus of breakage. On the basis of these and other data, we suggest that AML-associated chromosome 2 fragility in the mouse is a consequence of domain-specific fragility in genomic domains containing numerous genes critical to the hemopoietic system. Copyright © Crown Copyright 2002. Recorded with the permission of the controller of Her Majesty's Stationery Office. Published by Wiley-Liss, Inc. [source] First report of cyromazine resistance in a population of UK house fly (Musca domestica) associated with intensive livestock productionPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2010Howard A Bell Abstract BACKGROUND: House fly control in livestock-rearing facilities is heavily reliant on the use of the larvicide cyromazine. While extensive use of this compound has led to the development of resistance in several countries, no elevated tolerance has so far been reported from the United Kingdom. RESULTS: Tolerance to cyromazine in larvae derived from a field strain collected at an intensive pig unit was significantly elevated over that of insects taken from a susceptible laboratory strain. Resistance factors (RFs) of 2.9 and 2.4 were returned for assays initiated with eggs and neonate larvae respectively. The RF for field strain larvae exposed from neonate increased significantly to 3.9 and 5.6 following rounds of selection at 1.0 and then 1.5 mg kg,1 cyromazine. CONCLUSION: Low-level resistance to cyromazine in UK house flies is reported here for the first time. The geographic extent of this resistance is unknown but, if widespread, may lead to control failures in the future, and indicates that careful stewardship of this compound in the United Kingdom is now required. © Crown copyright 2010. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Recent advances in computational fluid dynamics relevant to the modelling of pesticide flow on leaf surfacesPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 1 2010C Richard Glass Abstract Increasing societal and governmental concern about the worldwide use of chemical pesticides is now providing strong drivers towards maximising the efficiency of pesticide utilisation and the development of alternative control techniques. There is growing recognition that the ultimate goal of achieving efficient and sustainable pesticide usage will require greater understanding of the fluid mechanical mechanisms governing the delivery to, and spreading of, pesticide droplets on target surfaces such as leaves. This has led to increasing use of computational fluid dynamics (CFD) as an important component of efficient process design with regard to pesticide delivery to the leaf surface. This perspective highlights recent advances in CFD methods for droplet spreading and film flows, which have the potential to provide accurate, predictive models for pesticide flow on leaf surfaces, and which can take account of each of the key influences of surface topography and chemistry, initial spray deposition conditions, evaporation and multiple droplet spreading interactions. The mathematical framework of these CFD methods is described briefly, and a series of new flow simulation results relevant to pesticide flows over foliage is provided. The potential benefits of employing CFD for practical process design are also discussed briefly. © Crown copyright 2009. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Insecticidal activity of scorpion toxin (ButaIT) and snowdrop lectin (GNA) containing fusion proteins towards pest species of different ordersPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 1 2010Elaine C Fitches Abstract BACKGROUND: The toxicity of a fusion protein, ButalT/GNA, comprising a venom toxin (ButaIT) derived from the red scorpion, Mesobuthus tamulus (F.), and Galanthus nivalis agglutinin (GNA), was evaluated under laboratory conditions against several pest insects. Insecticidal activity was compared with SFI1/GNA, a fusion comprising a venom toxin (SFI1) derived from the European spider Segestria florentina (Rossi) and GNA, which has been previously demonstrated to be effective against lepidopteran and hemipteran pests, and to GNA itself. RESULTS: Injection assays demonstrated that both fusion proteins were toxic to lepidopteran larvae, dipteran adults, coleopteran adults and larvae and dictyopteran nymphs. ButalT/GNA was more toxic than SFI1/GNA in all cases. GNA itself made a minor contribution to toxicity. Oral toxicity of ButalT/GNA towards lepidopteran pests was confirmed against neonate Spodoptera littoralis (Boisd.), where incorporation at 2% dietary protein resulted in 50% mortality and > 85% reduction in growth compared with controls. ButaIT/GNA was orally toxic to Musca domestica L. adults, causing 75% mortality at 1 mg mL,1 in aqueous diets and, at 2 mg g,1 it was orally toxic to Tribolium castaneum (Herbst.), causing 60% mortality and a 90% reduction in growth. CONCLUSIONS: Toxicity of the ButaIT/GNA recombinant fusion protein towards a range of insect pests from different orders was demonstrated by injection bioassays. Feeding bioassays demonstrated the potential use of the ButaIT/GNA fusion protein as an orally active insecticide against lepidopteran, dipteran and coleopteran pests. These experiments provide further evidence that the development of fusion protein technology for the generation of new, biorational, anti-insect molecules holds significant promise. © Crown Copyright 2009. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Incidents of bee poisoning with pesticides in the United Kingdom, 1994,2003PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 11 2007Elizabeth A Barnett Abstract For over 20 years, the UK Agriculture Departments have monitored the direct effects of pesticides on beneficial insects, mainly honeybees (Apis mellifera, L.) and bumblebees (Bombus terrestris, L.), as part of the Wildlife Incident Investigation Scheme (WIIS). The Central Science Laboratory (CSL) has contributed to WIIS by providing the required laboratory skills for the determination of bee diseases and the expert analytical experience necessary to determine low-level pesticide residues and interpret these results. The results from WIIS form part of the pesticide regulatory process coordinated by the Pesticides Safety Directorate (PSD) and are published each year. This paper has reviewed the data from WIIS over the 10 year period from 1994 to 2003. The overall trend is that suspected poisoning incidents, reported by beekeepers and the general public, have declined from 56 incidents per year to 23 incidents per year. The number of these incidents that have been attributed to pesticide poisoning has also declined, from 25 incidents to five incidents per year. The possible reasons for these changes and the circumstances involved in the bee poisoning incidents are discussed. However, the source of the pesticide in bee poisoning incidents is often uncertain and the likely cause of these incidents and any trends over time are also discussed. © Crown copyright 2007. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Use of models to assess the reduction in contamination of water bodies by agricultural pesticides through the implementation of policy instruments: a case study of the Voluntary Initiative in the UKPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 12 2006James Garratt Abstract Through normal agricultural use, pesticides may reach environmental water bodies via several routes of entry. Various policies and initiatives exist to reduce the effects of pesticides in the environment. One such initiative in place in the UK is the Voluntary Initiative (VI). The VI is a voluntary scheme put forward by the Crop Protection Association with other crop protection and farming organisations to reduce the environmental impacts of pesticides. Mathematical models of pesticide fate can usefully be applied to examine the impact of factors influencing the contamination of water bodies by pesticides. The work reported here used water quality models to examine how changes in farmer behaviour could potentially impact pesticide contamination of environmental water bodies. As far as possible, uncalibrated, standard regulatory models were used. Where suitable models were not available, simple models were defined for the purposes of the study and calibrated using literature data. Scenarios were developed to represent different standards of practice with respect to pesticide user behaviour. The development of these scenarios was guided by the Crop Protection Management Plan (CPMP) aspect of the VI. A framework for the use of modelling in the evaluation of the VI is proposed. The results of the modelling study suggest that, in several areas, widespread adoption of the measures proposed in the VI could lead to reductions in pesticide contamination of environmental water bodies. These areas include pesticide contamination from farmyards, spray drift and field runoff. In other areas (including pesticide leaching to groundwater and contamination of surface water from field drains) the benefits that may potentially be gained from the VI are less clear. A framework to evaluate the VI should take into consideration the following aspects: (1) groundwater is more at risk when there is a combination of leachable compounds, vulnerable soils, shallow groundwater and high product usage; (2) surface water contamination from drains is most likely when heavy rain falls soon after application, the soils are vulnerable and product usage is high; (3) surface water contamination from drift is most likely when the distance between the spray boom and water body is small and product usage is high; (4) surface water contamination from farmyards is dependent on the nature of the farmyard surface, the competence of the spray operator and the level of product usage. Any policy or initiative to reduce pesticide contamination should be measured against farmer behaviour in these areas. © Crown copyright 2006. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Cluster ion beam profiling of organics by secondary ion mass spectrometry , does sodium affect the molecular ion intensity at interfaces?RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 24 2008Felicia M. Green The use of cluster ion beam sputtering for depth profiling organic materials is of growing technological importance and is a very active area of research. At the 44th IUVSTA Workshop on "Sputtering and Ion Emission by Cluster Ion Beams", recent results were presented of a cluster ion beam depth profile of a thin organic molecular layer on a silicon wafer substrate. Those data showed that the intensity of molecular secondary ions is observed to increase at the interface and this was explained in terms of the higher stopping power in the substrate and a consequently higher sputtering yield and even higher secondary ion molecular sputtering yield. An alternative hypothesis was postulated in the workshop discussion which may be paraphrased as: "under primary ion bombardment of an organic layer, mobile ions such as sodium may migrate to the interface with the inorganic substrate and this enhancement of the sodium concentration increases the ionisation probability, so increasing the molecular ion yield observed at the interface". It is important to understand if measurement artefacts occur at interfaces for quantification as these are of great technological relevance , for example, the concentration of drug in a drug delivery system. Here, we evaluate the above hypothesis using a sample that exhibits regions of high and low sodium concentration at both the organic surface and the interface with the silicon wafer substrate. There is no evidence to support the hypothesis that the probability of molecular secondary ion ionisation is related to the sodium concentration at these levels. © Crown copyright 2008. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] The utility of ultra-performance liquid chromatography/electrospray ionisation time-of-flight mass spectrometry for multi-residue determination of pesticides in strawberryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 17 2008Michael J. Taylor The utility of ultra-performance liquid chromatography/orthogonal-acceleration time-of flight mass spectrometry (UPLC/TOFMS) for the rapid qualitative and quantitative analysis of 100 pesticides targeted in strawberry was assessed by comparing results with those obtained using a validated in-house UPLC tandem mass spectrometry (MS/MS) multi-residue method. Crude extracts from retail strawberry samples received as part of the 2007 annual UK pesticide residues in food surveillance programme were screened for the presence of pesticide residues using UPLC/TOFMS. Accurate mass measurement of positive and negative ions allowed their extraction following ,full mass range data acquisition' with negligible interference from background or co-eluting species observed during UPLC gradient separation (in a cycle time of just 6.5,min per run). Extracted ion data was used to construct calibration curves and to detect and identify any incurred residues (i.e. pesticides incorporated in or on the test material following application during cultivation, harvest and storage). Calibration using matrix-matched standards was performed over a narrow concentration range of 0.005,0.04,mg,kg,1 with determination coefficients (r2) ,0.99 for all analytes with the exception of malathion/fenarimol/fludioxanil (r2,=,0.98), quassia/pymetrazine (r2,=,0.97) and fenthion sulfone (r2,=,0.95). Residues found in selected samples ranged from 0.025,0.28,mg,kg,1 and were in excellent agreement with results obtained using UPLC/MS/MS. Mass measurement accuracies of ,5,ppm were achieved consistently throughout the separation, mass range and concentration range of interest thus providing the opportunity to obtain discrete elemental compositions of target ions. © Crown copyright 2008. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Spheroidal coordinate systems for modelling global atmospheresTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 630 2008A. A. White Abstract In meteorological dynamics it is common practice to represent the potential surfaces of apparent gravity (the geopotentials) as spheres, and consequently the use of spherical polar coordinates in models of the global atmosphere is widespread. Several writers have considered how oblate spheroidal coordinates might be used instead, thus enabling the Figure of the Earth to be better represented. It is observed here that oblate spheroidal coordinate systems are conventionally defined using confocal oblate spheroids, and that such spheroids are inappropriate representations of the geopotentials because they imply the wrong sign for the latitudinal variation of apparent gravity. Re-examination of a classical problem of Newtonian gravitation shows that, near the Earth, the geopotentials are to a very good approximation spheroids, but not spheroids of an analytically simple type. However, similar oblate spheroids are a qualitatively correct model of the near-Earth geopotentials, and are a quantitatively good approximation in so far as Newton's uniform-density model adequately describes the real Earth. An orthogonal curvilinear coordinate system based on similar oblate spheroids is proposed and examined. © Crown Copyright 2008. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd [source] The effect of small-scale hills on orographic dragTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 627 2007S. B. Vosper Abstract The purpose of this study is to investigate the extent to which the presence of hills with relatively short horizontal scales can influence the drag, due to mountain waves and flow blocking, exerted on the flow by larger-scale mountains. Numerical simulations of stratified flow over mountains are presented for flow over orography described by the linear superposition of broad mountains, whose length scales are large enough to generate mountain waves, and narrow corrugations, whose wavelengths fall below the minimum horizontal wavelength for stationary gravity waves. Results are presented for both two- and three-dimensional mountain shapes, and for a range of corrugation heights. It is shown that the corrugations can significantly reduce the amplitude of the mountain waves generated by the broader mountain, or they can suppress the unsteadiness of the wake. When these mechanisms make an important contribution to the total drag, this implies a significant drop in the total drag, compared to the sum of the contributions from the two scales of orography. From the point of view of drag parametrization, the extent to which the effect of the small-scale hills can be represented via an effective roughness length is investigated. © Crown Copyright 2007. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd [source] Influence of lee waves on the near-surface flow downwind of the PenninesTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 627 2007P. F. Sheridan Abstract The results of a recent field experiment focusing on the near-surface pressure and flow fields downstream of the Pennines in northern England are presented. The main aim of the experiment is the improvement of wind forecasts downstream of orography. Trapped lee waves commonly occur in westerly flow in this region, and during the experiment there were numerous instances of apparent flow separation, indicating the formation of lee-wave rotors. The spatial variability of the near-surface flow in these circumstances is closely linked to the positions of lee-wave crests and troughs aloft, and appears to be a response to pressure gradients induced by the lee waves. For large-amplitude waves, it has been possible to demonstrate a correlation between the fractional change of the flow speed across the measurement array (which if large enough may lead to flow separation) and a normalized pressure-perturbation amplitude. For a group of lee-wave cases during which the cross-mountain flow is strong, a rapid decrease in the Scorer parameter within the lower portion of the troposphere appears to be a prerequisite for rotors to form. However, this does not guarantee their occurrence. For a fixed Scorer-parameter profile, idealized two-dimensional simulations indicate that the lee-wave-induced pressure-perturbation amplitude, and hence the occurrence of rotors, is controlled largely by the strength of the wind upstream close to the mountain-top level. It seems that the combination of a favourable Scorer-parameter profile and sufficiently strong low-level winds is required for rotors to develop. © Crown Copyright 2007. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Fish movements: the introduction pathway for topmouth gudgeon Pseudorasbora parva and other non-native fishes in the UKAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2010G. H. Copp Abstract 1.The contamination of fish consignments (for stocking or aquaculture) is a major pathway by which non-native organisms, including fish, are introduced to new areas. One of the best examples of this is the topmouth gudgeon Pseudorasbora parva, which was accidentally imported into Romania and then throughout Europe in consignments of Asian carp species. 2.The introduction and spread of topmouth gudgeon in the UK has been linked to imports and movements of the ornamental variety (golden orfe) of ide Leuciscus idus. To examine this hypothesis, relationships between authorized movements of both native and non-native fish species (in particular ide) and the occurrence in England of topmouth gudgeon were tested at the 10×10,km scale. 3.Topmouth gudgeon occurrence in the wild was significantly correlated with the trajectories of movements of ornamental fish species (ide/orfe, sunbleak Leucaspius delineatus) as well as a few non-ornamental fish species (European catfish Silurus glanis, Atlantic salmon Salmo salar and grass carp Ctenopharyngodon idella). 4.These results highlight the mechanism by which non-native fish species disperse from the point of first introduction, and especially that movements of fish within the country represent an important mechanism for accidental introductions of non-native species. © Crown copyright 2010. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Vegetation communities of British lakes: a revised classification scheme for conservationAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2007Catherine Duigan Abstract 1.A revised classification scheme is described for standing waters in Britain, based on the TWINSPAN analysis of a dataset of aquatic plant records from 3447 lakes in England, Wales and Scotland, which is held by the Joint Nature Conservation Committee. 2.Separate ecological descriptions of 11 distinct lake groups (A,J) are presented with summary environmental data, macrophyte constancy tables and maps showing their distribution. These lake groups include small dystrophic waters dominated by Sphagnum spp.; large, acid, upland lakes supporting a diversity of plant species, including Juncus bulbosus, Littorella uniflora, Lobelia dortmanna and Myriophyllum alterniflorum; low-altitude, above-neutral lakes with a high diversity of plant species, characterized by the presence of Potamogeton spp., Chara spp. or water-lilies and other floating-leaved vegetation; and coastal, brackish lakes, with macroalgae. 3.The Plant Lake Ecotype Index (PLEX) is presented as an indicator of changing lake environments. PLEX scores reflecting the new classification scheme have been developed for individual plant species and lakes. Applications of the index are demonstrated. 4.There is discussion of possible applications of the data collected and the resultant classification, in the context of the Habitats Directive, the Water Framework Directive and other conservation requirements. © Crown copyright 2006. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Magnetic ghosts: mineral magnetic measurements on Roman and Anglo-Saxon graves,,ARCHAEOLOGICAL PROSPECTION, Issue 3 2004N. T. Linford Abstract The location of inhumations, in the absence of ferrous grave goods, often presents a considerable challenge to archaeological geophysics, given the small size of the features and the slight physical contrast between the fill of the grave and the surrounding subsoil. Even during excavation, the identification of graves may be complicated where site conditions do not favour the preservation of human skeletal remains and only a subtle soil stain is likely to survive. A recent initiative in the UK has seen the formation of the Buried Organic-matter,Decomposition Integrated with Elemental Status (BODIES) research group, to examine the decomposition of organic artefacts in ancient graves with respect to localized changes in pH, redox potential and nutrient status. This paper presents initial results from a limited mineral magnetic study of two grave sites in an attempt to ascertain whether the decomposition of organic remains may lead to a detectable magnetic signature within the soil. Results from a series of isothermal, hysteresis and magneto-thermal experiments will be presented together with surface magnetometer and topsoil susceptibility surveys. Copyright © Crown Copyright 2004. Recorded with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Scavenging efficiency of rainfall on black carbon aerosols over an urban environmentATMOSPHERIC SCIENCE LETTERS, Issue 3 2005K. Madhavi Latha Abstract Black carbon (BC) aerosols are the optically absorbing part of carbonaceous aerosols that have significantly different optical and radiative properties. The present study addresses the estimation of black carbon aerosol scavenging coefficient by using ground-based measurements over an urban environment of India, namely, Hyderabad. Extensive ground measurements of black carbon have been carried out during January to December 2004 over a tropical urban environment of Hyderabad. Seasonal variations of black carbon aerosol mass concentration showed high values during dry season and low values during monsoon season. The diurnal variations of BC suggest that the concentrations increased by a factor of ,2 during morning and evening hours compared to afternoon hours. Drastic reduction in black carbon aerosol loading has been observed during rainy days. The statistical fit between black carbon aerosol mass concentration and rainfall suggests the reduction of ,3.6 µg/m3 in atmospheric black carbon aerosol loading for every 1-mm increase in rainfall intensity over the study area. The scavenging coefficient of black carbon aerosols is found to be 1.64 × 10,5 s,1. © Crown Copyright 2005. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Use of a stochastic precipitation nowcast scheme for fluvial flood forecasting and warningATMOSPHERIC SCIENCE LETTERS, Issue 1 2005Clive Pierce Abstract In collaboration with the Bureau of Meteorology (Melbourne, Australia), the Met Office (Joint Centre for Hydro,Meteorological Research, UK) has developed a stochastic precipitation nowcast scheme, designed to model and predict the PDF of surface rain rate and rain accumulation in space and time. Here we demonstrate the range of probabilistic products generated by the scheme, and their potential applications for fluvial flood forecasting and warning. With the aid of a hydrological model (the PDM), we consider the use of ensembles of predicted catchment rain accumulation in evaluating the range of possible river flow responses from a given catchment. When employed in conjunction with a catchment specific, cost-based decision-making model, we highlight the value of PDFs of forecast catchment rainfall accumulation and river flow as an aid to objective decision making within the flood warning process. Crown Copyright 2005. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] Growth and reproduction of threatened native crucian carp Carassius carassius in small ponds of Epping Forest, south-east EnglandAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 7 2009Ali Serhan Tarkan Abstract 1.The crucian carp Carassius carassius is a species of cyprinid fish native to south-east England, but few studies exist on its growth and reproduction in England, and the species is threatened by introductions of its Asiatic congener, goldfish Carassius auratus. To increase knowledge of the crucian carp as a means of aiding its conservation, the present study assesses the growth (back-calculated length at age, body condition) and reproduction (fecundity, egg size, length and age at maturity) of crucian carp in small ponds of Epping Forest (north-east London, England). 2.Evaluation of growth and reproduction data with published data for populations from northern Europe (i.e. latitude ,50°) suggest that growth is very variable, even within the same area, and that data on reproductive indices, in particular length and age at maturity, are scarce. In England, the length at age trajectory of crucian carp living in sympatry with feral goldfish Carassius auratus did not differ significantly from allopatric crucian carp populations, but crucian carp body condition and relative fecundity (eggs per body weight) were highest, and mean age and standard length at maturity were lowest in sympatry with goldfish. 3.These data suggest that somatic growth and reproductive output may be maximized in crucian carp when confronted by coexistence with feral goldfish. However, the potential impact of goldfish introductions on crucian carp growth and reproduction requires further study, involving a much larger number of crucian carp populations, both in allopatry and sympatry with feral goldfish populations. © Crown copyright 2009. Reproduced with the permission of Her Majesty's stationery Office. Published by John Wiley & Sons, Ltd. [source] | ||||||||||||||||