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In 1999, Whiten et al. (Nature, 399:682-685) published comparative analyses of 65 behavioral patterns from 7 African field sites. In 2001, this database was expanded to 9 sites (Whiten et al., Behaviour, 138: 1481-1516). These are the published products of a research collaboration, the Chimpanzee Cultures Project, which includes all long-term studies of wild chimpanzees as studied by African, American, Asian and European researchers. However, the first stage of CCP barely scratches the surface, as data from over 40 sites have been collected and need collating. The Chimpanzee Cultures Website seeks to do so, and is the only such resource based on primary data. It can be found at http://culture.st-and.ac.uk/chimp The collective database is huge, and so affords the potential for ethnological analyses. Key aspects of the Chimpanzee Cultures Website include: Behavior Definition and Distribution (presence and extent, by pattern and site), Behavior Example (text and images, from drawings to video, by pattern). Study Location and Site Report (biotic and abiotic characteristics, by site), Graphical Display (dynamically generated matrix display of pattern distribution across Africa), Active Cross-Referencing (interconnections of all the above). Thus, one can ask such questions as: In how many populations is leaf grooming customary? Are West African chimpanzees culturally different from East African ones? Is the grooming-handclasp similar in details of performance at Mahale (Tanzania) versus Kibale (Uganda)? The Chimpanzee Cultures Website is supported by the Centre for Social Learning and Cognitive Evolution at the University of St. Andrews, Scotland. Expanding and extending it is an ongoing project.

Hedgerows are valuable habitats for biodiversity in farmed landscapes. The herbaceous vegetation at the hedge base is an important component of this habitat but its condition in Britain has deteriorated due to a combination of nutrient and pesticide contamination, and inappropriate management or neglect. The condition of herbaceous hedgerow vegetation is included in policy targets for biodiversity conservation, so a strategy is required for its restoration. This vegetation can be highly variable, so a classification of the main types is required to set realistic objectives. Vegetation classifications based on species' functional characteristics can have more general application that those based on species identity. Using existing datasets from a countrywide survey, a functional classification of herbaceous vegetation from hedgerows in Britain was developed. Cluster analysis of vegetation plots, based on attributes of the species present, produced thirteen vegetation types in six broad groups. These were differentiated by the association of the component species with woodland, grassland or arable habitats and by gradients of soil nutrient status and pH, light availability, disturbance and grazing tolerance. By using species' ecological characteristics as a basis for the classification, the condition of vegetation can be established and the prevailing environment predicted. From this information, a realistic strategy for restoration can then be determined. [ABSTRACT FROM AUTHOR]

Abstract: In this work high quality cobalt oxide silica membranes were synthesized on alumina supports using a sol–gel, dip coating method. The membranes were subsequently connected into a steel module using a graphite based proprietary sealing method. The sealed membranes were tested for single gas permeance of He, H2, N2 and CO2 at temperatures up to 600 °C and feed pressures up to 600 kPa. Pressure tests confirmed that the sealing system was effective as no gas leaks were observed during testing. A H2 permeance of 1.9 × 10−7 mol m−2 s−1 Pa−1 was measured in conjunction with a H2/CO2 permselectivity of more than 1500, suggesting that the membranes had a very narrow pore size distribution and an average pore diameter of approximately 3 Å. The high temperature testing demonstrated that the incorporation of cobalt oxide into the silica matrix produced a structure with a higher thermal stability, able to resist thermally induced densification up to at least 600 °C. Furthermore, the membranes were tested for H2/CO2 binary feed mixtures between 400 and 600 °C. At these conditions, the reverse of the water gas shift reaction occurred, inadvertently generating CO and water which increased as a function of CO2 feed concentration. The purity of H2 in the permeate stream significantly decreased for CO2 feed concentrations in excess of 50 vol%. However, the gas mixtures (H2, CO2, CO and water) had a more profound effect on the H2 permeate flow rates which significantly decreased, almost exponentially as the CO2 feed concentration increased. [Copyright &y& Elsevier]

Abstract: This article provides an overview of conventional and developing gas processing technologies for CO2 and N2 removal from natural gas. We consider process technologies based on absorption, distillation, adsorption, membrane separation and hydrates. For each technology, we describe the fundamental separation mechanisms involved and the commonly applied process flow schemes designed to produce pipeline quality gas (typically 2% CO2, <3% N2) and gas to feed a cryogenic gas plant (typically 50ppmv CO2, 1% N2). Amine absorption technologies for CO2 and H2S removal (acid gas treating) are well-established in the natural gas industry. The advantages and disadvantages of the conventional amine- and physical-solvent-based processes for acid gas treating are discussed. The use of CO2 selective membrane technologies for bulk separation of CO2 is increasing in the natural gas industry. Novel low-temperature CO2 removal technologies such as ExxonMobil’s Controlled Freeze Zone™ process and rapid cycle pressure swing adsorption processes are also emerging as alternatives to amine scrubbers in certain applications such as for processing high CO2 concentration gases and for developing remote gas fields. Cryogenic distillation remains the leading N2 rejection technology for large scale (feed rates greater than 15MMscfd) natural gas and liquefied natural gas plants. However, technologies based on CH4 selective absorption and adsorption, as well as N2 selective pressure swing adsorption technologies, are commercially available for smaller scale gas processing facilities. The review discusses the scope for the development of better performing CO2 selective membranes, N2 selective solvents and N2 selective adsorbents to both improve separation power and the durability of the materials used in novel gas processing technologies. [Copyright &y& Elsevier]

Abstract: Oxygen production from BSCF (Ba0.5Sr0.5Co0.8Fe0.2O3− δ ) and yttrium-doped BSCF (Ba0.5Sr0.5Co0.8Fe0.175Y0.025O3− δ ) hollow fibres was investigated, and the role of yttrium in the crystal structure was further explored using high-temperature X-ray diffraction. Yttrium substitution acted to increase the oxygen flux significantly, from 4.9 to 7.0mlcm−2 min−1 at 900°C for the BSCF and the BSCFY membranes, respectively. Permeation was particularly enhanced at lower temperatures, between 66% and 92% over the range 650–800°C. The lattice expansion determined from high temperature X-ray diffraction measurements in air was similar for both compositions, suggesting that the higher oxygen fluxes obtained for BSCFY hollow fibres could be attributed to the higher non-stoichiometry due to yttrium addition to the BSCF crystal structure. In addition, the improvement of oxygen fluxes for small wall thickness (∼0.3mm) hollow fibres operating below the critical length (i.e. limited surface kinetics regime) indicates that yttrium has enhanced the surface exchange rates. XRD patterns showed split peaks around 2θ 31° and 56° above 200°C, likely corresponding to a coexisting hexagonal perovskite phase. This peak-splitting was more pronounced for BSCFY, suggesting that the kinetics of the hexagonal phase formation may be faster for the yttrium-doped perovskite. The lattice volume of BSCFY expanded more than BSCF when exposed to nitrogen at 900°C, confirming a higher release of oxygen and enhanced oxygen non-stoichiometry. [Copyright &y& Elsevier]

Abstract: This work investigates the partial substitution of yttrium in place of iron in BSCF to form Ba0.5Sr0.5Co0.8Fe0.2− x Y x O3− δ , where x varied between 0 and 0.2. X-ray diffraction patterns showed the formation of a perovskite cubic phase structure up to x =0.15, whilst the full substitution of yttrium (x =0.2) for iron resulted in a non-cubic crystal structure that did not exhibit oxygen permeation. The yttrium partial substitution in BSCFY discs (1.2mm thick) delivered best results for x =0.025, as oxygen fluxes reached 2.05mlcm−2 min−1 at 900°C, an increase of 160% as compared to a blank BSCF (x =0) membrane. This was attributed to the combined effect of the formation of a greater number of oxygen vacancies, together with improved ion mobility, associated with the beneficial yttrium substitution into the BSCF perovskite structure which stemmed from the crystal lattice expansion. [Copyright &y& Elsevier]

Abstract: Nanostructured gas separation membranes are promising candidates for the separation of CO2 from the flue gas of fossil power plants. Well-defined atomic structures in the range of a few Angstrom are required to separate CO2 from N2 in existing post-combustion power plants, and H2 from CO2 in prospective integrated gasification combined cycle (IGCC) power plants. Today, CO2/N2 and H2/CO2 gas separation with membranes has been demonstrated mainly on a laboratory scale, while less is known about membrane performance and stability under real conditions. To extend the state of knowledge, a test bed was put into operation in the flue gas stream of a hard-coal-fired power plant (EnBW Rheinhafendampfkraftwerk, Karlsruhe), which enabled the long-term functional test of ceramic as well as polymer gas separation membranes for up to 1100h. For the first time, a CO2 enrichment from 12vol.% in the flue gas to 57vol.% in the permeate of a polymer membrane was demonstrated. Due to operating this membrane in direct contact with flue gas, the flow rate was reduced from 0.86 to 0.07m3/m2 hbar within the first 400h. This reduction was mainly caused by the deposition of ash particles and gypsum suggesting the need of developing effective membrane protection strategies. In addition, ceramic supported Ti0.5Zr0.5O2 and metal supported Co–SiO2 membranes were tested under the same conditions. Even if demonstration of CO2 gas separation with ceramic membranes requires further modifications of the membrane materials, the long-term exposure in the power plant led to notable results regarding adherence of functional layers and chemical stability. [ABSTRACT FROM AUTHOR]

The invasion of native habitats by exotic, or alien, plant species has received considerable attention recently from policy, research, and practical conservation management perspectives. However, a new hypothesis for species dynamics in Britain suggests that a small number of aggressive native plant species (termed 'thugs') may have an equal, or greater, impact on native species and habitats than exotic species. Here, we examine this hypothesis using multivariate techniques with field-layer cover data collected during a country-wide survey of British woodlands. Multivariate analysis of these data identified a north-south gradient on the first axis, and that 20 of the 25 National Vegetation Classification woodland types were sampled within the study. The most abundant field-layer species included three of the proposed native 'thugs', i.e. Rubus fruticosus, Pteridium aquilinum and Hedera helix in addition to the native woodland indicator species Mercurialis perennis. Variation partitioning was used to compare the relative importance of native field-layer 'thug' species with invading alien shrub and tree species relative to other environmental drivers. The variation in the field-layer data-set explained by the three native 'thug' species was significant, but they explained a relatively small proportion of the variation relative to other environmental variables (climate, soil, management factors etc.). They did, however, explain almost four times as much variation as the three alien species that were significantly correlated with field-layer species composition ( Acer pseudoplatanus, Impatiens glandulifera, Rhododendron ponticum). The results of this analysis suggest that the field-layer of British woodlands is impacted as much by native 'thug' species, as it is from 'aliens'. Concern about the impact of these native 'thug' species has been reported previously, but their impact has not previously been compared to the impact of invading aliens. It is hoped that this analysis will do two things, first to act as a sound baseline for assessing any changing balance that should occur in the future, and second, to prompt both ecologists and conservationists to develop woodland management policies based on sound science. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to assess the impacts of nitrogen (N) deposition on the composition of plant species. The study uses the integrated soil-vegetation models to predict the composition of plant species as function of atmospheric N and acidity deposition and coupled models were used in an inverse way in determining critical loads. The result shows that both model-based and empirical critical loads are the powerful tools to evaluate a reliable value for defined ecosystems.

The NHS Clinical Knowledge Summaries provide an online source of evidence-based information and practical know-how on the common conditions managed in primary and first-contact care. [ABSTRACT FROM AUTHOR]

Question: What are the impacts of factors controlling patterns of change in woodland field-layer vegetation, through time? Location: Wytham Woods, Oxford, UK (51°41′ N, 1°19′ W). Methods: Species occurrence was monitored in 163 permanent plots three times between 1973 and 2002 and related to management compartment and history. The dataset was analysed using a combination of ordination methods, univariate and multivariate analysis of variance and HOF modelling. Results: The two key findings of this paper are: (1) that the species composition of ancient woodlands (often cited as a conservation goal), may be moving along an `undesirable' trajectory, from a conservation viewpoint; and (2) that the impact of a synergistic effect of changing canopy dynamics, nitrogen deposition and a rising deer population has resulted in an increase in grass species, at the expense of woodland herbs. These findings have significant implications for the practical conservation of similar habitats across Europe. Conclusions: The analytical methodology presented here allowed detailed assessment of the potential roles of a range of environmental factors controlling change. The methodology may be applicable to other long-term studies of vegetation, and is particularly appropriate for identification of cross-site drivers, such as pollutant load and climate change. [ABSTRACT FROM AUTHOR]

This seventh best-practice review examines four series of common primary care questions in laboratory medicine: (1) blood count abnormalities 2; (2) cardiac troponins; (3) high-density lipoprotein cholesterol; and (4) viral diseases 2. The review is presented in a question-answer format, with authorship attributed for each question series. The recommendations are a précis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents and evidence-based medicine reviews, supplemented by Medline Embase searches to identify relevant primary research documents. The recommendations are not standards, but form a guide to be set in the clinical context. Most are consensus based rather than evidence based. They will be updated periodically to take account of new information. [ABSTRACT FROM AUTHOR]

1 We investigated the role of non-native species (neophytes) in common British plant communities using botanical data from two stratified random surveys carried out in 1990 and 1998. 2 We found that from 16 851 plots surveyed in 1998 there were 123 non-native species found mostly in arable, tall grass/herb and fertile grassland habitats. Invasive non-native species, e.g. Fallopia japonica, Impatiens glandulifera and Rhododendron ponticum, were uncommon in this survey. 3 Between 1990 and 1998 the total number of non-native species increased but the mean number of species per sample plot decreased. The mean cover of non-natives increased from 1.2% to 1.9%. 4 There were positive spatial and temporal relationships between non-native and native species diversity. However, there was a weak negative relationship between changes in non-native cover and native diversity. 5 The species composition and ecological traits of communities containing non-natives were very different from those that did not contain them. 6 In the British countryside non-native species were mainly found in habitats with anthropogenic associations, high fertility, high number of ruderal species and high diversity. There is also an indication that successional shifts where competitive invasive species dominate involve non-native species. 7 National-scale changes in plant community composition are likely to be closely correlated with external land-use impacts. Changes such as eutrophication, nitrogen deposition and increased fertility in infertile habitats are likely to benefit both native and non-native invasive species; however, currently these trends benefit native species much more often than non-natives. 8 Non-native species are known to have significant effects on native species at local scales in many countries; however, at the landscape scale in Great Britain they are best considered as symptoms of disturbance and land-use change rather than a direct threat to biodiversity. [ABSTRACT FROM AUTHOR]

This best practice review examines four series of common primary care questions in laboratory medicine: (I) ‘minor’ blood platelet count and haemoglobin abnormalities; (ii) diagnosis and monitoring of anaemia caused by iron deficiency; (iii) secondary hyperlipidaemia and hypertriglyceridaemia; and (iv) glycated haemoglobin and microalbumin use in diabetes. The review is presented in question-answer format, referenced for each question series. The recommendations represent a précis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents and evidence-based medicine reviews, supplemented by Medline Embase searches to identify relevant primary research documents. They are not standards, but form a guide to be set in the clinical context. Most of the recommendations are based on consensus rather than evidence. They will be updated periodically to take account of new information. [ABSTRACT FROM AUTHOR]

1 Simulation models of forest stand dynamics have increased understanding of over-storey vegetation functioning, and have facilitated the development of tools capable of assessing possible successional trajectories. However, few models incorporate the response of the field layer vegetation despite it being another key component of forest ecosystems. 2 Our main objective was to assess the degree to which field-layer vegetation composition in forests is determined by variables operating at different scales, from regional (e.g. climate, location) to local factors (e.g. basal area of canopy trees, management). 3 We used data gathered during a nationwide forest survey to assess the relative effects of a broad spectrum of environmental variables on species composition. Variation partitioning was used to examine the relative contribution of subsets of environmental variables such as site spatial variation, boundary type and presence of herbivores. 4 Ordination confirmed hypotheses that field layer vegetation is primarily structured by two composite geo-climatic gradients. However, variation partitioning demonstrated that site- and plot-scale management factors also strongly influence the floristic composition of forest patches. 5 Disturbance variables (site boundary type/regional presence of deer) accounted for considerable species variation, exceeding that due to either site spatial variation or forest structure. 6 This is the first time variation attributable to such a comprehensive range of environmental variables has been quantified for forests surveyed at a national scale. We thus provide a context within which regional studies, or analyses considering a more limited range of factors, can be viewed, and a framework from which robust models of floristic response to gradual and episodic natural and anthropogenic disturbances may be developed. 7 The methodology we present, including a novel technique for the identification and removal of outliers in large data sets, provides a unique and standardized means of assessing the relative importance of diverse environmental drivers across a range of habitat types at the landscape scale, and is readily applicable elsewhere. [ABSTRACT FROM AUTHOR]

Abstract: Vehicular emissions of NOx and NH3 result in elevated concentrations of nitrogen at roadside verges. To determine the extent that vehicular nitrogen emissions, disturbance and management affect the vegetation composition of road verges, a survey of 92 verges in Scotland was carried out with sites stratified by background nitrogen deposition and road type. NOx and NH3 concentrations were monitored at 15 key sites for a year, and showed a decreasing gradient with increasing distance from the road. Ellenberg fertility indices of the vegetation communities also showed a general decrease with increasing distance from the road, but there was no straightforward correlation with NOx and NH3 air concentrations between sites. Cover of bare ground, ruderal species and salt-tolerant species were highest at the verge edge. The proximity of the verge to traffic is important both in terms of NOx and NH3 gradients, but also for deposited salt, grit and physical disturbance. [Copyright &y& Elsevier]

to explore how mothers of children with recurrent abdominal pain view seeking medical help on behalf of their children.qualitative interview study.paediatric clinics and schools.purposive sample of 28 mothers of children with recurrent abdominal pain.Beliefs concerning recurrent abdominal pain, the respective roles of doctors and mothers and the nature and quality of interactions with doctors.Mothers of children with recurrent abdominal pain reported shaping the way they discussed the child's problem with doctors according to their beliefs about their own roles and the beliefs they perceived doctors to hold about recurrent abdominal pain. Where they were seeking help in managing the pain, they often felt undermined and threatened and responded to this by stressing the physical aspects of the child's presentation.Doctors may need to acknowledge actively mothers’ competence in order to establish a therapeutic alliance. [ABSTRACT FROM AUTHOR]