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Selected AbstractsCover Picture: (Adv. Eng.ADVANCED ENGINEERING MATERIALS, Issue 8 2010Mater. The cover figure is selected from the article of G. Wilde et.al. It illustrates a strain map showing a detail of the in-plane rigid-body rotation ,xy. Hot spots refer to dislocation cores. The greenish colour represents the zero distortion. [source] Competitive Abnormal Grain Growth between Allotropic Phases in Nanocrystalline NickelADVANCED MATERIALS, Issue 10 2010L. N. Brewer Electron backscatter diffraction-generated phase map showing the distribution of the abnormally grown grains for both the face centered cubic (red) and hexagonal close packed (blue) phases. Annealing condition was 17,h at 548,K. [source] Modelling disease spread in a novel host: rabies in the European badger Meles melesJOURNAL OF APPLIED ECOLOGY, Issue 6 2002G. C. Smith Summary 1Although the red fox Vulpes vulpes is the main reservoir of rabies in Europe, badger Meles meles populations are known to be drastically affected. Models of badger population dynamics are combined with a fox/rabies model to examine the possibility of rabies spread in high-density badger populations, such as those found in the United Kingdom (UK). 2Although some data exist on rabies epizootiology in the badger, there are no data on badger-to-badger contact rates (either healthy or diseased animals). As a starting point consensus expert opinion was used to devise contact probabilities, and the model was found to be insensitive to reasonable variation in these rates for the density of badgers at which these estimates were made. 3Density-dependent (but not density-independent) contact probabilities simulated short chains of infections that may occur in continental Europe at low badger densities, and simulated true epizootics at higher densities. 4Another possible reason for these short chains of infections in continental Europe is a very high level of fragmentation between social groups. 5Given the high level of territorial contiguity and possible contact rates found in some parts of the UK, the model suggests that rabies is capable of spreading within the UK badger population, and a provisional map showing the likelihood of an epizootic is presented. [source] Migration and sedimentation of spherical particles in a yield stress fluid flowing in a horizontal cylindrical pipeAICHE JOURNAL, Issue 10 2009Othmane Merkak Abstract This study looks at the dynamics of a particle suspended in a viscoplastic fluid, flowing in a horizontal circular cylindrical pipe. Inertia effects are negligible in comparison with viscous effects and plastic effects. The suspensions are highly stabilized and at rest the spheres cannot settle under gravity alone. The results of Merkak et al. (AIChE J. 2008;54:1129,1138) are extended, taking into consideration both particles of the same density or denser than the fluid and pipe-to-particle diameter ratios of 8 or 56. New migration phenomena in the sheared zone are thus evidenced when buoyancy forces are nil. In the case of particles denser than the fluid, it is shown how the spheres settle by bypassing the plug-flow zone. A map showing the stability of flowing suspensions could, thus, be drawn. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Invasive exotic aoudad (Ammotragus lervia) as a major threat to native Iberian ibex (Capra pyrenaica): a habitat suitability model approachDIVERSITY AND DISTRIBUTIONS, Issue 5 2007Pelayo Acevedo ABSTRACT The introduction of alien species to new environments is one of the main threats to the conservation of biodiversity. One particularly problematic example is that of wild ungulates which are increasingly being established in regions outside their natural distribution range due to human hunting interests. Unfortunately, we know little of the effects these large herbivores may have on the host ecosystems. This study deals with a first comparative analysis of the habitat requirements of two ungulate species that may be facing competition for resources in the south of Europe: the native Iberian ibex (Capra pyrenaica) and the exotic aoudad (Ammotragus lervia). The aoudad is a North African caprid introduced in 1970 as a game species in south-eastern Spain. It has adapted well, and populations have been freely expanding since then. Ecological Niche Factor Analysis is used to describe the realized niche of both species where their distribution ranges merge. Both species occupy marginal areas of rugged terrain in the region. Marginality is higher for the Iberian ibex, which also presents a higher tolerance of secondary environmental gradients than the aoudad. Highly suitable areas for each species are secondarily suitable for the other. Reclassified and cross-tabulated habitat suitability maps showing the areas of potential spatial coexistence and differences in ecological traits between both species are provided. The results obtained do not allow inferring resource competition between these species. However, current aoudad expansion could result in it invading the favoured habitats of the ibex. Inadequate hunting policy and monitoring, and increasing climatic resemblance of the study region to the native aoudad areas, due to a strong desertification process, are facilitating a high rate of expansion. We strongly recommend to eradicate or, at least, monitor these exotic populations, and promote active conservation practices, if one wants to preserve the unique natural resources present in this European region. [source] New plant protection information system in Hungary,EPPO BULLETIN, Issue 1 2000A. Pákozdi Data on the occurrence and spread of pests has been supplied by the Hungarian Plant Protection Organization for over 40 years. Since the 1970s, this service has been operated by the central station and the 20 county stations of the Plant Protection Organization. Data recorded on pest occurrence and developmental stage of pests and plants has been used to run a forecasting system at local and national levels. However, because of significant staff reductions in the Plant Protection Organization and the disappearance of independent forecasting groups, the reliability of the system, which was based on very specific data, has decreased. It has become necessary to develop a more reliable and flexible computer-aided system (Plant Protection Information System, PPIS), better adjusted to the political and economic changes that have occurred. A major element of the new system, introduced in 1997, is that excessively detailed recording was replaced by a more practical general approach with fewer subjective errors. Specialists from the county stations of the Plant Protection Organization monitor infestation levels of 73 pests in 20 crops using five qualification categories. The results obtained are input into the PPIS program, which processes them into user-friendly charts and maps showing the plant health situation in each county and in the country as a whole, as a basis for taking decisions on plant protection measures. [source] The ostrich in Egypt: past and presentJOURNAL OF BIOGEOGRAPHY, Issue 8 2001Nicolas Manlius Aim This article tracks the evolution of the distribution of ostrich populations, Struthio camelus L., 1758, in Egypt from the Late Pleistocene up to present times with a view to establishing a series of distribution maps for the historical period. An attempt is then made to describe and interpret these maps. Location The country considered is Egypt. Methods We compiled all the information about the presence of the ostrich in Egypt collected from the study of fossil remains, archaeological materials and from the narrative of travellers since the fourteenth century. From the accounts of these travellers, three maps showing the location of this birds in this country are established: from the end of the fourteenth century to the end of the seventeenth century; from the beginning of the eighteenth to the end of the nineteenth century; and lastly, for the twentieth century. Results The ostrich was abundant and broadly distributed in Egypt in the past. However, it has been constantly in decline. It disappeared from the north of the country and lived only in the southeast up to the end of the nineteenth century. The birds reappeared in the latter region at the beginning of the 1960s up to 1991 before disappearing from the country. Main conclusions The principal reasons for the decline of the ostrich in Egypt are the aridification caused by climatic changes and intensive hunting by humans. It is possible that this bird was not sighted in the country between the beginning of the twentieth century and the 1960s, not because it had disappeared, but most probably because it was sufficiently discrete to be noticed. But Retracer l'évolution de la distribution des populations d'autruches, Struthio camelus L., 1758, en Egypte depuis le Pléistocène final jusqu'à nos jours en vue d'établir une série de cartes de distribution pour l'époque historique. Décrire et interpréter ensuite ces cartes. Localisation Le pays considéré est l'Egypte. Méthodes Nous avons compilé toutes les informations portant sur la présence de l'autruche en Egypte, recueillies à partir de l'étude de fossiles des matériaux archéologiques, ou encore des écrits des voyageurs depuis le XIVe siècle. A partir des témoignages de ces voyageurs, trois cartes montrant la localisation de cet animal en Egypte seront établies: depuis la fin du XIVe siècle jusqu'à la fin du XVIIe siècle; depuis le début du XVIIIeà la fin du XIXe siècle; et enfin pour le XXe siècle. Résultats Dans le passé, les populations d'autruches étaient abondantes et largement répandues en Egypte. Cependant, elles n'ont pas cessé de régresser. Elles ont d'abord disparues du nord du pays pour ne plus survivre que dans le sud-est, et ce jusqu'à la fin du XIXe siècle. L'animal est reparut dans cette dernière région au début des années 1960 jusqu'en 1991, avant de disparaître du pays. Conclusions principales Les principales raisons pour lesquelles la population d'autruches a régressé en Egypte tiennent d'une aridification due à des changements climatiques ainsi qu'à une chasse outrancière par l'homme. Il est possible que cet oiseau n'aie pour ainsi dire plus été signalé dans le pays entre le début du XXe siècle et les années 1960, non parce qu'il en aurait disparu mais plutôt parce qu'il aurait su se faire suffisamment discret pour ne pas être repéré. [source] Analytical SuperSTEM for extraterrestrial materials researchMETEORITICS & PLANETARY SCIENCE, Issue 10 2009John P. Bradley The improved technical capabilities enable analyses previously not possible. Mineral structures can be directly imaged and analyzed with single-atomic-column resolution, liquids, and implanted gases can be detected, and UV-VIS optical properties can be measured. Detection limits for minor/trace elements in thin (<100 nm thick) specimens are improved such that quantitative measurements of some extend to the sub-500 ppm level. Electron energy-loss spectroscopy (EELS) can be carried out with 0.10,0.20 eV energy resolution and atomic-scale spatial resolution such that variations in oxidation state from one atomic column to another can be detected. Petrographic mapping is extended down to the atomic scale using energy-dispersive X-ray spectroscopy (EDS) and energy-filtered transmission electron microscopy (EFTEM) imaging. Technical capabilities and examples of the applications of SuperSTEM to extraterrestrial materials are presented, including the UV spectral properties and organic carbon K-edge fine structure of carbonaceous matter in interplanetary dust particles (IDPs), X-ray elemental maps showing the nanometer-scale distribution of carbon within GEMS (glass with embedded metal and sulfides), the first detection and quantification of trace Ti in GEMS using EDS, and detection of molecular H2O in vesicles and implanted H2 and He in irradiated mineral and glass grains. [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] | |||||||||||||