819 resultados para Nature study.
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During the 1970’s and 1980’s, the late Dr Norman Holme undertook extensive towed sledge surveys in the English Channel and some in the Irish Sea. Only a minority of the resulting images were analysed and reported before his death in 1989 but logbooks, video and film material has been archived in the National Marine Biological Library (NMBL) in Plymouth. A scoping study was therefore commissioned by the Joint Nature Conservation Committee and as a part of the Mapping European Seabed Habitats (MESH) project to identify the value of the material archived and the procedure and cost to undertake further work. The results of the scoping study are: 1. NMBL archives hold 106 videotapes (reel-to-reel Sony HD format) and 59 video cassettes (including 15 from the Irish Sea) in VHS format together with 90 rolls of 35 mm colour transparency film (various lengths up to about 240 frames per film). These are stored in the Archive Room, either in a storage cabinet or in original film canisters. 2. Reel-to-reel material is extensive and had already been selectively copied to VHS cassettes. The cost of transferring it to an accepted ‘long-life’ medium (Betamax) would be approximately £15,000. It was not possible to view the tapes as a suitable machine was not located. The value of the tapes is uncertain but they are likely to become beyond salvation within one to two years. 3. Video cassette material is in good condition and is expected to remain so for several more years at least. Images viewed were generally of poor quality and the speed of tow often makes pictures blurred. No immediate action is required. 4. Colour transparency films are in good condition and the images are very clear. They provide the best source of information for mapping seabed biotopes. They should be scanned to digital format but inexpensive fast copying is problematic as there are no between-frame breaks between images and machines need to centre the image based on between-frame breaks. The minimum cost to scan all of the images commercially is approximately £6,000 and could be as much as £40,000 on some quotations. There is a further cost in coding and databasing each image and, all-in-all it would seem most economic to purchase a ‘continuous film’ scanner and undertake the work in-house. 5. Positional information in ships logs has been matched to films and to video tapes. Decca Chain co-ordinates recorded in the logbooks have been converted to latitude and longitude (degrees, minutes and seconds) and a further routine developed to convert to degrees and decimal degrees required for GIS mapping. However, it is unclear whether corrections to Decca positions were applied at the time the position was noted. Tow tracks have been mapped onto an electronic copy of a Hydrographic Office chart. 6. The positions of start and end of each tow were entered to a spread sheet so that they can be displayed on GIS or on a Hydrographic Office Chart backdrop. The cost of the Hydrographic Office chart backdrop at a scale of 1:75,000 for the whole area was £458 incl. VAT. 7. Viewing all of the video cassettes to note habitats and biological communities, even by an experienced marine biologist, would take at least in the order of 200 hours and is not recommended. English Channel towed sledge seabed images. Phase 1: scoping study and example analysis. 6 8. Once colour transparencies are scanned and indexed, viewing to identify seabed habitats and biological communities would probably take about 100 hours for an experienced marine biologist and is recommended. 9. It is expected that identifying biotopes along approximately 1 km lengths of each tow would be feasible although uncertainties about Decca co-ordinate corrections and exact positions of images most likely gives a ±250 m position error. More work to locate each image accurately and solve the Decca correction question would improve accuracy of image location. 10. Using codings (produced by Holme to identify different seabed types), and some viewing of video and transparency material, 10 biotopes have been identified, although more would be added as a result of full analysis. 11. Using the data available from the Holme archive, it is possible to populate various fields within the Marine Recorder database. The overall ‘survey’ will be ‘English Channel towed video sled survey’. The ‘events’ become the 104 tows. Each tow could be described as four samples, i.e. the start and end of the tow and two areas in the middle to give examples along the length of the tow. These samples would have their own latitude/longitude co-ordinates. The four samples would link to a GIS map. 12. Stills and video clips together with text information could be incorporated into a multimedia presentation, to demonstrate the range of level seabed types found along a part of the northern English Channel. More recent images taken during SCUBA diving of reef habitats in the same area as the towed sledge surveys could be added to the Holme images.
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This research is concerned with the following environmental research questions: socio-ecological system complexity, especially when valuing ecosystem services; ecosystems stock and services flow sustainability and valuation; the incorporation of scale issues when valuing ecosystem services; and the integration of knowledge from diverse disciplines for governance and decision making. In this case study, we focused on ecosystem services that can be jointly supplied but independently valued in economic terms: healthy climate (via carbon sequestration and storage), food (via fisheries production in nursery grounds), and nature recreation (nature watching and enjoyment). We also explored the issue of ecosystem stock and services flow, and we provide recommendations on how to value stock and flows of ecosystem services via accounting and economic values respectively. We considered broadly comparable estuarine systems located on the English North Sea coast: the Blackwater estuary and the Humber estuary. In the past, these two estuaries have undergone major land-claim. Managed realignment is a policy through which previously claimed intertidal habitats are recreated allowing the enhancement of the ecosystem services provided by saltmarshes. In this context, we investigated ecosystem service values, through biophysical estimates and welfare value estimates. Using an optimistic (extended conservation of coastal ecosystems) and a pessimistic (loss of coastal ecosystems because of, for example, European policy reversal) scenario, we find that context dependency, and hence value transfer possibilities, vary among ecosystem services and benefits. As a result, careful consideration in the use and application of value transfer, both in biophysical estimates and welfare value estimates, is advocated to supply reliable information for policy making.
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Ecosystem models are often assessed using quantitative metrics of absolute ecosystem state, but these model-data comparisons are disproportionately vulnerable to discrepancies in the location of important circulation features. An alternative method is to demonstrate the models capacity to represent ecosystem function; the emergence of a coherent natural relationship in a simulation indicates that the model may have an appropriate representation of the ecosystem functions that lead to the emergent relationship. Furthermore, as emergent properties are large-scale properties of the system, model validation with emergent properties is possible even when there is very little or no appropriate data for the region under study, or when the hydrodynamic component of the model differs significantly from that observed in nature at the same location and time. A selection of published meta-analyses are used to establish the validity of a complex marine ecosystem model and to demonstrate the power of validation with emergent properties. These relationships include the phytoplankton community structure, the ratio of carbon to chlorophyll in phytoplankton and particulate organic matter, the ratio of particulate organic carbon to particulate organic nitrogen and the stoichiometric balance of the ecosystem. These metrics can also inform aspects of the marine ecosystem model not available from traditional quantitative and qualitative methods. For instance, these emergent properties can be used to validate the design decisions of the model, such as the range of phytoplankton functional types and their behaviour, the stoichiometric flexibility with regards to each nutrient, and the choice of fixed or variable carbon to nitrogen ratios.
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High level environmental screening study for offshore wind farm developments – marine habitats and species This report provides an awareness of the environmental issues related to marine habitats and species for developers and regulators of offshore wind farms. The information is also relevant to other offshore renewable energy developments. The marine habitats and species considered are those associated with the seabed, seabirds, and sea mammals. The report concludes that the following key ecological issues should be considered in the environmental assessment of offshore wind farms developments: • likely changes in benthic communities within the affected area and resultant indirect impacts on fish, populations and their predators such as seabirds and sea mammals; • potential changes to the hydrography and wave climate over a wide area, and potential changes to coastal processes and the ecology of the region; • likely effects on spawning or nursery areas of commercially important fish and shellfish species; • likely effects on mating and social behaviour in sea mammals, including migration routes; • likely effects on feeding water birds, seal pupping sites and damage of sensitive or important intertidal sites where cables come onshore; • potential displacement of fish, seabird and sea mammals from preferred habitats; • potential effects on species and habitats of marine natural heritage importance; • potential cumulative effects on seabirds, due to displacement of flight paths, and any mortality from bird strike, especially in sensitive rare or scarce species; • possible effects of electromagnetic fields on feeding behaviour and migration, especially in sharks and rays, and • potential marine conservation and biodiversity benefits of offshore wind farm developments as artificial reefs and 'no-take' zones. The report provides an especially detailed assessment of likely sensitivity of seabed species and habitats in the proposed development areas. Although sensitive to some of the factors created by wind farm developments, they mainly have a high recovery potential. The way in which survey data can be linked to Marine Life Information Network (MarLIN) sensitivity assessments to produce maps of sensitivity to factors is demonstrated. Assessing change to marine habitats and species as a result of wind farm developments has to take account of the natural variability of marine habitats, which might be high especially in shallow sediment biotopes. There are several reasons for such changes but physical disturbance of habitats and short-term climatic variability are likely to be especially important. Wind farm structures themselves will attract marine species including those that are attached to the towers and scour protection, fish that associate with offshore structures, and sea birds (especially sea duck) that may find food and shelter there. Nature conservation designations especially relevant to areas where wind farm might be developed are described and the larger areas are mapped. There are few designated sites that extend offshore to where wind farms are likely to be developed. However, cable routes and landfalls may especially impinge on designated sites. The criteria that have been developed to assess the likely marine natural heritage importance of a location or of the habitats and species that occur there can be applied to survey information to assess whether or not there is anything of particular marine natural heritage importance in a development area. A decision tree is presented that can be used to apply ‘duty of care’ principles to any proposed development. The potential ‘gains’ for the local environment are explored. Wind farms will enhance the biodiversity of areas, could act as refugia for fish, and could be developed in a way that encourages enhancement of fish stocks including shellfish.
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Objective To evaluate participants' perceptions of the impact on them of an additional six months' training beyond the standard 12 month general practice vocational training scheme. Design Qualitative study using focus groups. Setting General practice vocational training in Northern Ireland. Participants 13 general practitioner registrars, six of whom participated in the additional six months' training, and four trainers involved in the additional six months' training. Main outcome measures: Participants' views about their experiences in 18 month and 12 month courses. Results Participants reported that the 12 month course was generally positive but was too pressurised and focused on examinations, and also that it had a negative impact on self care. The nature of the learning and assessment was reported to have left participants feeling averse to further continuing education and lacking in confidence. In contrast, the extended six month component was reported to have restimulated learning by focusing more on patient care and promoting self directed learning. It developed confidence, promoted teamwork, and gave experience of two practice contexts, and was reported as valuable by both ex-registrars and trainers. However, both the 12 and 18 month courses left participants feeling underprepared for practice management and self care. Conclusions 12 months' training in general practice does not provide doctors with the necessary competencies and confidence to enter independent practice. The extended period was reported to promote greater professional development, critical evaluation skills, and orientation to lifelong learning but does not fill all the gaps.
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We present photometric and spectroscopic data of the Type II-P supernova (SN II-P) 2003gd, which was discovered in M74 close to the end of its plateau phase. SN 2003gd is the first Type II supernova ( SN) to have a directly confirmed red supergiant ( RSG) progenitor. We compare SN 2003gd to SN 1999 em, a similar SN II-P, and estimate an explosion date of 2003 March 18. We determine a reddening towards the SN of E(B-V) = 0.14 +/- 0.06, using three different methods. We also calculate three new distances to M74 of 9.6 +/- 2.8, 7.7 +/- 1.7 and 9.6 +/- 2.2 Mpc. The former was estimated using the standard candle method (SCM), for Type II supernovae (SNe II), and the latter two using the brightest supergiants method (BSM). When combined with existing kinematic and BSM distance estimates, we derive a mean value of 9.3 +/- 1.8 Mpc. SN 2003gd was found to have a lower tail luminosity compared with other normal Type II-P supernovae ( SNe II-P) bringing into question the nature of this SN. We present a discussion concluding that this is a normal SN II-P, which is consistent with the observed progenitor mass of 8(-2)(+4) M-circle dot.
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Primary objective: To compare patients with traumatic brain injury (TBI) with controls on sub-types of aggression and explore the role of social desirability.
Design: Quasi-experimental, matched-participants design.
Methods and procedures: Sixty-nine participants were included in the study. The sample comprised a TBI group (n = 24), a spinal cord injury (SCI) group (n = 21) and an uninjured (UI) group of matched healthy volunteers (n = 24). Participants were given self-report measures of aggression, social desirability and impulsivity. Sixty-one independent ‘other-raters’ were nominated, who rated participant pre-morbid and post-morbid aggression.
Main outcomes and results: Using standardized norms, 25–39% of participants with TBI were classified as high average–very high on anger and 35–38% as high average–very high on verbal aggression. Other-raters rated participants with TBI as significantly higher on verbal aggression than SCI and UI participants. There were no differences between the groups on physical aggression. The TBI group also had higher levels of impulsivity than SCI and UI groups. Social desirability was a highly significant predictor of self-reported aggression for the entire sample.
Conclusions: Impulsive verbal aggression and anger are the principal aggressive traits after brain injury. Physical aggression may present in extreme cases after TBI, but appears less prominent overall in this population. Social desirability, previously overlooked in research examining TBI aggression, emerged as an influential variable that should be considered in future TBI research.
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Purpose. To determine the prevalence, nature, and degree of accommodative dysfunction among children with different types and severities of cerebral palsy (CP) in Northern Ireland. Methods. Ninety subjects with CP (aged 4–15 years) were recruited through the Northern Ireland CP Register (NICPR). Modified Nott dynamic retinoscopy was used to measure lag and lead of accommodation at three test distances: 25 cm (4 D), 16.7 cm (6 D), and 10 cm (10 D) with the distance correction in place. Accommodative function was also assessed in an age-matched control group (n = 125) for comparison. Each subject’s neurologic status was derived from the NICPR. Results. Children with CP demonstrate significantly reduced accommodative responses compared with their neurologically normal peers. Of the subjects with CP, 57.6% demonstrated an accommodative lag outside normal limits at one or more distances. Reduced accommodative responses were significantly associated with more severe motor and intellectual impairments (ANOVA P = 0.001, P < 0.01, respectively). Conclusions. Brain injury such as that present in CP has a significant impact on accommodative function. These findings have implications for the optometric care of children with CP and inform our understanding of the impact of early brain injury on visual development.
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In the last years, “Inquiry-Based Science Education” methodologies (IBSE) are being recommended by European institutions in order to improve the competence levels and the attitudes towards science of primary and secondary school students. Therefore, the aim of this study is to test the effectiveness of an IBSE methodology, the Methodology of Problem Solving as an Investigation (MPSI), for the teaching-learning process of planning of experiments in the fourth level of Spanish Secondary Education. By means of the students’ solutions for a series of open problems, the progress in the learning of the competences related to the planning of experiments has been analyzed, along with the influence of the methodology on the development of these competencies. The results show a students’ command from higher to lower levels on: emission of hypothesis, design of the experiment, qualitative analysis, identification of variables and reformulation of the open problem. Furthermore, the Methodology has contributed to an improvement of the scientific competence in the area of planning experiments.
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Evidence on the persistence of innovation sheds light on the nature of the innovation process and can guide appropriate policy development. This paper examines innovation persistence in Ireland and Northern Ireland using complementary quantitative and case-study approaches. Panel data derived from innovation surveys is used, and suggests very different results to previous analyses of innovation persistence primarily based on patents data. Product and process innovation are found to exhibit strong general persistence but we find no evidence that persistence is stronger among highly active innovators. Our quantitative evidence is most strongly consistent with a process of cumulative accumulation at plant level. Our case-studies highlight a number of factors which can either interrupt or stimulate this process including market volatility, plants’ organisational context and regulatory changes. Notably, however, the balance of influences on product and process innovation persistence differs, with product innovation persistence linked more strongly to strategic factors and process changes more often driven by market pressures.
© 2007 Elsevier B.V. All rights reserved.
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Objective: We aimed to explore, using qualitative methods, the perspectives of patients with hypertension on issues relating to concordance in prescribing.
Method: This study took place in NHS general practices in Northern Ireland. A purposeful sample of patients who had been prescribed anti-hypertensive medication for at least one year were invited to participate in focus groups or semi-structured interviews; data were analysed using constant comparison.
Main outcome measures: The perspectives of patients with hypertension on issues relating to concordance in prescribing.
Results: Twenty-five individuals participated in five focus groups; two participated in semi-structured interviews. Participants felt they could make valuable contributions to consultations regarding their management. They were prepared to negotiate with GPs regarding their medication, but most deferred to their doctor’s advice, perceiving doctors’ attitudes and time constraints as barriers to their greater involvement in concordant decision-making. They had concerns about taking anti-hypertensive drugs, were aware of lifestyle influences on hypertension and reported using personal strategies to facilitate adherence and reduce the need to take medication.
Conclusions: Participants indicated a willingness to be?involved in concordance in prescribing anti- hypertensive medication but needed health professionals to address their concerns and confusion about the nature of hypertension. These findings suggest that there is a need for doctors and other healthcare professionals with responsibility for prescribing to develop skills specifically to explore the beliefs and views underlying an individual’s medication use. Such skills may need to be developed through specific training programmes at both undergraduate and postgraduate level.
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Software product development is recognised as difficult due to the intangible nature of the product, requirements elicitation, effective progress measurement, and so forth. In this paper, we describe some of the challenges of software product development and how the challenges are being met by lean management principles and techniques. Specifically, we examine lean principles and techniques that were devised by Toyota and other manufacturers over the last 50 years. Applying lean principles to software development projects has been advocated for over ten years and it will be shown that the extensive lean literature is a valuable source of ideas for software development. A case study with a software development organisation, Timberline Inc., will demonstrate that lean principles and techniques can be successfully applied to software product development.
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Density functional theory has been used to study the adsorption of hydroxyl at low and high coverages and also to investigate the nature of the intermediate in the H2O formation reaction on Pt(111). At low coverages [1/9 of a monolayer (ML) to 1/3 ML] OH binds preferentially at bridge and top sites with a chemisorption energy of similar to2.25 eV. At high coverages (1/2 ML to 1 ML) H bonding between adjacent hydroxyls causes: (i) an enhancement in OH chemisorption energy by about 15%; (ii) a strong preference for OH adsorption at top sites; and (iii) the formation of OH networks. The activation energy for the diffusion of isolated OH groups along close packed rows of Pt atoms is 0.1 eV. This low barrier coupled with H bonding between neighboring OH groups indicates that hydroxyls are susceptible to island formation at low coverages. Pure OH as well as coadsorbed OH and H can be ruled out as the observed low temperature intermediate in the water formation reaction. Instead we suggest that the intermediate consists of a mixed OH+H2O overlayer with a macroscopic surface coverage of 3/4 ML in a 2:1 ratio of OH and H2O. (C) 2001 American Institute of Physics.
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The nature of the surface species formed at the surface of 2 wt.% Pt/CeO2 catalyst during the forward water-gas-shift (WGS, CO + H2O -> CO2 + H-2) and the reverse reaction (RWGS) were essentially identical. More, the surface concentration of formate, carbonate and carbonyl species was similar in each case. The presence of well-resolved IR bands allowed an unequivocal relative quantitative analysis of each species, avoiding the use of the carboxylate stretching region (1600-1200 cm(-1)). However, the quantitative analysis in the case of an isotopic study was complicated due to the overlapping of the various isotope bands, yet this problem could be overcome by integrating the high-wavenumber part of the bands. The reactivity of the surface species formed under RWGS conditions was followed under two different gaseous streams. Firstly, the reactivity of these intermediates were followed under an inert gas (i.e., At), in which case carbonates were essentially stable and less reactive than formates. Secondly, the reactivity of the same surface species was followed when switching to the corresponding C-13-labelled feed (i.e., (CO2)-C-13 + H-2), in which case carbonates were exchanged significantly faster than formates. While carbonates species have been reported as reaction intermediate under reaction conditions, the increased stability or surface poisoning by these carbonates in the absence of reaction mixture was highlighted. Ultimately, this work re-emphasises the need to use steady-state conditions if the true operando reactivity of the adsorbates and structure of the solid are to be determined. (c) 2005 Elsevier B.V. All rights reserved.
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The nature of the silver phases of Ag/Al2O3 catalysts (prepared by silver nitrate impregnation followed by calcination) was investigated by X-ray diffractograms (XRD), transmission electron microscopy (TEM) and UV-VIS analyses and related to the activity of the corresponding materials for the oxidation of NO to NO2. The UV-VIS spectrum of the 1.2 wt.% Ag/Al2O3 exhibited essentially one band associated with Ag+ species and the NO2 yields measured over this material were negligible. A 10 wt.% Ag/Al2O3 material showed the presence of oxidic species of silver (as isolated Ag+ cations and silver aluminate), but the UV-VIS data also revealed the presence of some metallic silver. The activity for the NO oxidation to NO2 of this sample was moderate. The same 10% sample either reduced in H-2 or used for the C3H6-selective catalytic reduction (SCR) of NO showed a significantly larger proportion of silver metallic phases and these samples displayed a high activity for the formation of NO2. These data show that the structure and nature of the silver phases of Ag/Al2O3 catalysts can markedly change under reaction feed containing only a fraction of reducing agent (i.e. 500 ppm of propene) in net oxidizing conditions (2.5% O-2). The low activity for N-2 formation during the C3H6-SCR of NO (reported in an earlier study) over the high loading sample can. therefore, he related to the presence of metallic silver. which is yet a good catalyst for NO oxidation to NO2. The reverse observations apply for the oxide species observed over the low loading sample, which is a good SCR catalyst but do not oxidize NO to NO2. (C) 2002 Elsevier Science B.V. All rights reserved.