Global Map (global + map)

Distribution by Scientific Domains


Selected Abstracts


Global map of the prevalence of symptoms of rhinoconjunctivitis in children: The International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three

ALLERGY, Issue 1 2009
N. Aït-Khaled
Background:, Phase One of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global patterns of prevalence and severity of symptoms of rhinoconjunctivitis in children in 1993,1997. Methods:, International Study of Asthma and Allergies in Childhood Phase Three was a cross-sectional survey performed 5,10 years after Phase One using the same methodology. Phase Three covered all of the major regions of the world and involved 1 059 053 children of 2 age groups from 236 centres in 98 countries. Results:, The average overall prevalence of current rhinoconjunctivitis symptoms was 14.6% for the 13- to 14-year old children (range 1.0,45%). Variation in the prevalence of severe rhinoconjunctivitis symptoms was observed between centres (range 0.0,5.1%) and regions (range 0.4% in western Europe to 2.3% in Africa), with the highest prevalence being observed mainly in the centres from middle and low income countries, particularly in Africa and Latin America. Co-morbidity with asthma and eczema varied from 1.6% in the Indian sub-continent to 4.7% in North America. For 6- to 7-year old children, the average prevalence of rhinoconjunctivitis symptoms was 8.5%, and large variations in symptom prevalence were also observed between regions, countries and centres. Discussion:, Wide global variations exist in the prevalence of current rhinoconjunctivitis symptoms, being higher in high vs low income countries, but the prevalence of severe symptoms was greater in less affluent countries. Co-morbidity with asthma is high particularly in Africa, North America and Oceania. This global map of symptom prevalence is of clinical importance for health professionals. [source]


Searching for the source regions of martian meteorites using MGS TES: Integrating martian meteorites into the global distribution of igneous materials on Mars

METEORITICS & PLANETARY SCIENCE, Issue 6 2003
Victoria E. HAMILTON
We deconvolved the TES data set using laboratory spectra of 6 martian meteorites (Los Angeles, Zagami, ALH A77005, Nakhla, ALH 84001, and Chassigny) as end members, along with atmospheric and surface spectra previously derived from TES data. Global maps (16 pixels/degree) of the distribution of each meteorite end member show that meteorite-like compositions are not present at or above TES detectability limits over most of the planet's dust-free regions. However, we have confidently identified local-scale (100s-1000s km2) concentrations of olivine- and orthopyroxene-bearing materials similar to ALH A77005, Chassigny, and ALH 84001 in Nili Fossae, in and near Ganges Chasma, in the Argyre and Hellas basin rims, and in Eos Chasma. Nakhla-like materials are identified near the detection limit throughout the eastern Valles Marineris region and portions of Syrtis Major. Basaltic shergottites were not detected in any spatially coherent areas at the scale of this study. Martian meteorite-like lithologies represent only a minor portion of the dust-free surface and, thus, are not representative of the bulk composition of the ancient crust. Meteorite-like spectral signatures identified above TES detectability limits in more spatially restricted areas ([source]


Responses of global plant diversity capacity to changes in carbon dioxide concentration and climate

ECOLOGY LETTERS, Issue 11 2008
F. I. Woodward
Abstract We model plant species diversity globally by country to show that future plant diversity capacity has a strong dependence on changing climate and carbon dioxide concentration. CO2 increase, through its impact on net primary production and warming is predicted to increase regional diversity capacity, while warming with constant CO2 leads to decreases in diversity capacity. Increased CO2 concentrations are unlikely to counter projected extinctions of endemic species, shown in earlier studies to be more strongly dependent on changing land use patterns than climate per se. Model predictions were tested against (1) contemporary observations of tree species diversity in different biomes, (2) an independent global map of contemporary species diversity and (3) time sequences of plant naturalisation for different locations. Good agreements between model, observations and naturalisation patterns support the suggestion that future diversity capacity increases are likely to be filled from a ,cosmopolitan weed pool' for which migration appears to be an insignificant barrier. [source]


Global patterns of plant diversity and floristic knowledge

JOURNAL OF BIOGEOGRAPHY, Issue 7 2005
Gerold Kier
Abstract Aims, We present the first global map of vascular plant species richness by ecoregion and compare these results with the published literature on global priorities for plant conservation. In so doing, we assess the state of floristic knowledge across ecoregions as described in floras, checklists, and other published documents and pinpoint geographical gaps in our understanding of the global vascular plant flora. Finally, we explore the relationships between plant species richness by ecoregion and our knowledge of the flora, and between plant richness and the human footprint , a spatially explicit measure of the loss and degradation of natural habitats and ecosystems as a result of human activities. Location, Global. Methods, Richness estimates for the 867 terrestrial ecoregions of the world were derived from published richness data of c. 1800 geographical units. We applied one of four methods to assess richness, depending on data quality. These included collation and interpretation of published data, use of species,area curves to extrapolate richness, use of taxon-based data, and estimates derived from other ecoregions within the same biome. Results, The highest estimate of plant species richness is in the Borneo lowlands ecoregion (10,000 species) followed by nine ecoregions located in Central and South America with , 8000 species; all are found within the Tropical and Subtropical Moist Broadleaf Forests biome. Among the 51 ecoregions with , 5000 species, only five are located in temperate regions. For 43% of the 867 ecoregions, data quality was considered good or moderate. Among biomes, adequate data are especially lacking for flooded grasslands and flooded savannas. We found a significant correlation between species richness and data quality for only a few biomes, and, in all of these cases, our results indicated that species-rich ecoregions are better studied than those poor in vascular plants. Similarly, only in a few biomes did we find significant correlations between species richness and the human footprint, all of which were positive. Main conclusions, The work presented here sets the stage for comparisons of degree of concordance of plant species richness with plant endemism and vertebrate species richness: important analyses for a comprehensive global biodiversity strategy. We suggest: (1) that current global plant conservation strategies be reviewed to check if they cover the most outstanding examples of regions from each of the world's major biomes, even if these examples are species-poor compared with other biomes; (2) that flooded grasslands and flooded savannas should become a global priority in collecting and compiling richness data for vascular plants; and (3) that future studies which rely upon species,area calculations do not use a uniform parameter value but instead use values derived separately for subregions. [source]


Underwater SLAM in man-made structured environments

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 11-12 2008
David Ribas
This paper describes a navigation system for autonomous underwater vehicles (AUVs) in partially structured environments, such as dams, harbors, marinas, and marine platforms. A mechanically scanned imaging sonar is used to obtain information about the location of vertical planar structures present in such environments. A robust voting algorithm has been developed to extract line features, together with their uncertainty, from the continuous sonar data flow. The obtained information is incorporated into a feature-based simultaneous localization and mapping (SLAM) algorithm running an extended Kalman filter. Simultaneously, the AUV's position estimate is provided to the feature extraction algorithm to correct the distortions that the vehicle motion produces in the acoustic images. Moreover, a procedure to build and maintain a sequence of local maps and to posteriorly recover the full global map has been adapted for the application presented. Experiments carried out in a marina located in the Costa Brava (Spain) with the Ictineu AUV show the viability of the proposed approach. © 2008 Wiley Periodicals, Inc. [source]


Celiac disease: India on the global map

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2006
Surender Kumar Yachha
[source]


Global map of the prevalence of symptoms of rhinoconjunctivitis in children: The International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three

ALLERGY, Issue 1 2009
N. Aït-Khaled
Background:, Phase One of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global patterns of prevalence and severity of symptoms of rhinoconjunctivitis in children in 1993,1997. Methods:, International Study of Asthma and Allergies in Childhood Phase Three was a cross-sectional survey performed 5,10 years after Phase One using the same methodology. Phase Three covered all of the major regions of the world and involved 1 059 053 children of 2 age groups from 236 centres in 98 countries. Results:, The average overall prevalence of current rhinoconjunctivitis symptoms was 14.6% for the 13- to 14-year old children (range 1.0,45%). Variation in the prevalence of severe rhinoconjunctivitis symptoms was observed between centres (range 0.0,5.1%) and regions (range 0.4% in western Europe to 2.3% in Africa), with the highest prevalence being observed mainly in the centres from middle and low income countries, particularly in Africa and Latin America. Co-morbidity with asthma and eczema varied from 1.6% in the Indian sub-continent to 4.7% in North America. For 6- to 7-year old children, the average prevalence of rhinoconjunctivitis symptoms was 8.5%, and large variations in symptom prevalence were also observed between regions, countries and centres. Discussion:, Wide global variations exist in the prevalence of current rhinoconjunctivitis symptoms, being higher in high vs low income countries, but the prevalence of severe symptoms was greater in less affluent countries. Co-morbidity with asthma is high particularly in Africa, North America and Oceania. This global map of symptom prevalence is of clinical importance for health professionals. [source]


Ammonia map shows hot spots

ASTRONOMY & GEOPHYSICS, Issue 4 2009
Article first published online: 20 JUL 200
The ESA MetOp satellite has provided the data for researchers to produce the first global map of ammonia emissions. The map shows high production over areas of intensive agriculture, as well as sources not previously known. [source]


What a difference copy number variation makes

BIOESSAYS, Issue 4 2007
Hildegard Kehrer-Sawatzki
DNA copy number variation (CNV) represents a considerable source of human genetic diversity. Recently,1 a global map of copy number variation in the human genome has been drawn up which reveals not only the ubiquity but also the complexity of this type of variation. Thus, two human genomes may differ by more than 20 Mb and it is likely that the full extent of CNV still remains to be discovered. Nearly 3000 genes are associated with CNV. This high degree of variability with regard to gene copy number between two individuals challenges definitions of normality. Many CNVs are located in regions of complex genomic structure and this currently limits the extent to which these variants can be genotyped by using tagging SNPs. However, some CNVs are already amenable to genome-wide association studies so that their influence on human phenotypic diversity and disease susceptibility may soon be determined. BioEssays 29:311,313, 2007. © 2007 Wiley Periodicals, Inc. [source]