WorldWideScience

Sample records for expanding global distribution

  1. Consequences of the expanding global distribution of Aedes albopictus for dengue virus transmission.

    Science.gov (United States)

    Lambrechts, Louis; Scott, Thomas W; Gubler, Duane J

    2010-05-25

    The dramatic global expansion of Aedes albopictus in the last three decades has increased public health concern because it is a potential vector of numerous arthropod-borne viruses (arboviruses), including the most prevalent arboviral pathogen of humans, dengue virus (DENV). Ae. aegypti is considered the primary DENV vector and has repeatedly been incriminated as a driving force in dengue's worldwide emergence. What remains unresolved is the extent to which Ae. albopictus contributes to DENV transmission and whether an improved understanding of its vector status would enhance dengue surveillance and prevention. To assess the relative public health importance of Ae. albopictus for dengue, we carried out two complementary analyses. We reviewed its role in past dengue epidemics and compared its DENV vector competence with that of Ae. aegypti. Observations from "natural experiments" indicate that, despite seemingly favorable conditions, places where Ae. albopictus predominates over Ae. aegypti have never experienced a typical explosive dengue epidemic with severe cases of the disease. Results from a meta-analysis of experimental laboratory studies reveal that although Ae. albopictus is overall more susceptible to DENV midgut infection, rates of virus dissemination from the midgut to other tissues are significantly lower in Ae. albopictus than in Ae. aegypti. For both indices of vector competence, a few generations of mosquito colonization appear to result in a relative increase of Ae. albopictus susceptibility, which may have been a confounding factor in the literature. Our results lead to the conclusion that Ae. albopictus plays a relatively minor role compared to Ae. aegypti in DENV transmission, at least in part due to differences in host preferences and reduced vector competence. Recent examples of rapid arboviral adaptation to alternative mosquito vectors, however, call for cautious extrapolation of our conclusion. Vector status is a dynamic process that in the

  2. Consequences of the expanding global distribution of Aedes albopictus for dengue virus transmission.

    Directory of Open Access Journals (Sweden)

    Louis Lambrechts

    2010-05-01

    Full Text Available The dramatic global expansion of Aedes albopictus in the last three decades has increased public health concern because it is a potential vector of numerous arthropod-borne viruses (arboviruses, including the most prevalent arboviral pathogen of humans, dengue virus (DENV. Ae. aegypti is considered the primary DENV vector and has repeatedly been incriminated as a driving force in dengue's worldwide emergence. What remains unresolved is the extent to which Ae. albopictus contributes to DENV transmission and whether an improved understanding of its vector status would enhance dengue surveillance and prevention. To assess the relative public health importance of Ae. albopictus for dengue, we carried out two complementary analyses. We reviewed its role in past dengue epidemics and compared its DENV vector competence with that of Ae. aegypti. Observations from "natural experiments" indicate that, despite seemingly favorable conditions, places where Ae. albopictus predominates over Ae. aegypti have never experienced a typical explosive dengue epidemic with severe cases of the disease. Results from a meta-analysis of experimental laboratory studies reveal that although Ae. albopictus is overall more susceptible to DENV midgut infection, rates of virus dissemination from the midgut to other tissues are significantly lower in Ae. albopictus than in Ae. aegypti. For both indices of vector competence, a few generations of mosquito colonization appear to result in a relative increase of Ae. albopictus susceptibility, which may have been a confounding factor in the literature. Our results lead to the conclusion that Ae. albopictus plays a relatively minor role compared to Ae. aegypti in DENV transmission, at least in part due to differences in host preferences and reduced vector competence. Recent examples of rapid arboviral adaptation to alternative mosquito vectors, however, call for cautious extrapolation of our conclusion. Vector status is a dynamic

  3. Consequences of the Expanding Global Distribution of Aedes albopictus for Dengue Virus Transmission

    Science.gov (United States)

    Lambrechts, Louis; Scott, Thomas W.; Gubler, Duane J.

    2010-01-01

    The dramatic global expansion of Aedes albopictus in the last three decades has increased public health concern because it is a potential vector of numerous arthropod-borne viruses (arboviruses), including the most prevalent arboviral pathogen of humans, dengue virus (DENV). Ae. aegypti is considered the primary DENV vector and has repeatedly been incriminated as a driving force in dengue's worldwide emergence. What remains unresolved is the extent to which Ae. albopictus contributes to DENV transmission and whether an improved understanding of its vector status would enhance dengue surveillance and prevention. To assess the relative public health importance of Ae. albopictus for dengue, we carried out two complementary analyses. We reviewed its role in past dengue epidemics and compared its DENV vector competence with that of Ae. aegypti. Observations from “natural experiments” indicate that, despite seemingly favorable conditions, places where Ae. albopictus predominates over Ae. aegypti have never experienced a typical explosive dengue epidemic with severe cases of the disease. Results from a meta-analysis of experimental laboratory studies reveal that although Ae. albopictus is overall more susceptible to DENV midgut infection, rates of virus dissemination from the midgut to other tissues are significantly lower in Ae. albopictus than in Ae. aegypti. For both indices of vector competence, a few generations of mosquito colonization appear to result in a relative increase of Ae. albopictus susceptibility, which may have been a confounding factor in the literature. Our results lead to the conclusion that Ae. albopictus plays a relatively minor role compared to Ae. aegypti in DENV transmission, at least in part due to differences in host preferences and reduced vector competence. Recent examples of rapid arboviral adaptation to alternative mosquito vectors, however, call for cautious extrapolation of our conclusion. Vector status is a dynamic process that in

  4. Germany's expanding role in global health.

    Science.gov (United States)

    Kickbusch, Ilona; Franz, Christian; Holzscheiter, Anna; Hunger, Iris; Jahn, Albrecht; Köhler, Carsten; Razum, Oliver; Schmidt, Jean-Olivier

    2017-08-26

    Germany has become a visible actor in global health in the past 10 years. In this Series paper, we describe how this development complements a broad change in perspective in German foreign policy. Catalysts for this shift have been strong governmental leadership, opportunities through G7 and G20 presidencies, and Germany's involvement in managing the Ebola virus disease outbreak. German global health engagement has four main characteristics that are congruent with the health agenda of the Sustainable Development Goals; it is rooted in human rights, multilateralism, the Bismarck model of social protection, and a link between development and investment on the basis of its own development trajectory after World War 2. The combination of momentum and specific characteristics makes Germany well equipped to become a leader in global health, yet the country needs to accept additional financial responsibility for global health, expand its domestic global health competencies, reduce fragmentation of global health policy making, and solve major incoherencies in its policies both nationally and internationally. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Global Landslide Hazard Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Landslide Hazard Distribution is a 2.5 minute grid of global landslide and snow avalanche hazards based upon work of the Norwegian Geotechnical Institute...

  6. Expanding Global Mindedness through a 4-H International Village

    Science.gov (United States)

    Seal, Susan D.; Peterson, Donna J.; Iwata, Chieko; Kobia, Caroline; Reddy, Raja

    2017-01-01

    With expanding global interdependence, it is vital that 4-H youths learn more about the ever-increasing diverse cultures in their own communities as well as expand their global mindedness and understanding of globalization. The 4-H International Village (a) offers a comfortable yet engaging avenue for youths to expand their knowledge of and…

  7. Global kinetic hybrid simulation for radially expanding solar wind

    Science.gov (United States)

    Dyadechkin, S.; Semenov, V. S.; Kallio, E.; Erkaev, N. V.; Alho, M.; Lammer, H.

    2017-08-01

    We present the results of a 1-D global kinetic simulation of the solar wind in spherical coordinates without a magnetic field in the region from the Sun to the Earth's orbit. Protons are considered as particles while electrons are considered as a massless fluid, with a constant temperature, in order to study the relation between the hybrid and hydrodynamic solutions. It is shown that the strong electric field in the hybrid model accelerates the protons. Since the electric field in the model is related to electron pressure, each proton in the initial Maxwellian velocity distribution function moves under the same forces as in the classical Parker Solar wind model. The study shows that the hybrid model results in very similar velocity and number density distributions along the radial distance as in the Parker model. In the hybrid simulations, the proton temperature is decreased with distance in 1 order of magnitude. The effective polytropic index of the proton population slightly exceeds 1 at larger distances with the maximum value ˜1.15 in the region near the Sun. A highly non-Maxwellian type of distribution function is initially formed. Further from the Sun, a narrow beam of the escaping protons is created which does not change much in later expansion. The results of our study indicates that already a nonmagnetized global hybrid model is capable of reproducing some fundamental features of the expanding solar wind shown in the Parker model and additional kinetic effects in the solar wind.

  8. Globally Happy: Individual Globalization, Expanded Capacities, and Subjective Wellbeing

    Science.gov (United States)

    Tsai, Ming-Chang; Chang, Heng-Hao; Chen, Wan-chi

    2012-01-01

    Deep integration of Asia into the global society necessarily affects wellbeing of local populations. This study proposes a notion of "extend capacities" to explain the relationships between individual globalization and subjective wellbeing among Asian populations in a context of increasing global integration. Using Amartya Sen's theory…

  9. An Expanded Model of Distributed Leadership in Organizational Knowledge Creation

    OpenAIRE

    Cannatelli, B.; Smith, B. J.; Giudici, A.; Jones, J; Conger, M.

    2016-01-01

    Based on a three-year qualitative, longitudinal case study of a social venture partnership, we extend the understanding of distributed leadership in organizational knowledge creation. We develop an expanded model of distributed leadership that identifies the antecedents, different forms, and enablers of distributed leadership in knowledge creation. Our findings move beyond a static and monolithic understanding of distributed leadership to illustrate how an expanded model informs the situation...

  10. Global Mangrove Forests Distribution, 2000

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Mangrove Forests Distribution, 2000 data set is a compilation of the extent of mangroves forests from the Global Land Survey and the Landsat archive with...

  11. Diaspora, Migration, and Globalization: Expanding the Discourse of Adult Education

    Science.gov (United States)

    Alfred, Mary V.

    2015-01-01

    This article explores how notions of diaspora, migration, and globalization intersect to inform identities and social realities of those who leave their homeland and resettle in other nations. It calls for expanding the discourse of adult education to incorporate critical studies of the diaspora to make visible the inequality and imbalance of…

  12. Global Multihazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Multihazard Frequency and Distribution is a 2.5 minute grid presenting a simple multihazard index based solely on summated single-hazard decile values. The...

  13. Distributed computing for global health

    CERN Document Server

    CERN. Geneva; Schwede, Torsten; Moore, Celia; Smith, Thomas E; Williams, Brian; Grey, François

    2005-01-01

    Distributed computing harnesses the power of thousands of computers within organisations or over the Internet. In order to tackle global health problems, several groups of researchers have begun to use this approach to exceed by far the computing power of a single lab. This event illustrates how companies, research institutes and the general public are contributing their computing power to these efforts, and what impact this may have on a range of world health issues. Grids for neglected diseases Vincent Breton, CNRS/EGEE This talk introduces the topic of distributed computing, explaining the similarities and differences between Grid computing, volunteer computing and supercomputing, and outlines the potential of Grid computing for tackling neglected diseases where there is little economic incentive for private R&D efforts. Recent results on malaria drug design using the Grid infrastructure of the EU-funded EGEE project, which is coordinated by CERN and involves 70 partners in Europe, the US and Russi...

  14. Regulatory Considerations Associated with the Expanded Adoption of Distributed Solar

    Energy Technology Data Exchange (ETDEWEB)

    Bird, L.; McLaren, J.; Heeter, J.; Linvill, C.; Shenot, J.; Sedano, R.; Migden-Ostrander, J.

    2013-11-01

    Increased adoption of distributed PV, and other forms of distributed generation, have the potential to affect utility-customer interactions, system costs recovery, and utility revenue streams. If a greater number of electricity customers choose to self-generate, demand for system power will decrease and utility fixed costs will have to be recovered over fewer kilowatt hours of sales. As such, regulators will need to determine the value and cost of additional distributed PV and determine the appropriate allocation of the costs and benefits among consumers. The potential for new business models to emerge also has implications for regulation and rate structures that ensure equitable solutions for all electricity grid users. This report examines regulatory tools and rate designs for addressing emerging issues with the expanded adoption of distributed PV and evaluates the potential effectiveness and viability of these options going forward. It offers the groundwork needed in order for regulators to explore mechanisms and ensure that utilities can collect sufficient revenues to provide reliable electric service, cover fixed costs, and balance cost equity among ratepayers -- while creating a value proposition for customers to adopt distributed PV.

  15. Global Earthquake Hazard Distribution - Peak Ground Acceleration

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Hazard Distribution-peak ground acceleration is a 2.5 minute grid of global earthquake hazards developed using Global Seismic Hazard Program...

  16. Global Earthquake Hazard Distribution - Peak Ground Acceleration

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Hazard Distribution-Peak Ground Acceleration is a 2.5 by 2.5 minute grid of global earthquake hazards developed using Global Seismic Hazard Program...

  17. Climate Science's Globally Distributed Infrastructure

    Science.gov (United States)

    Williams, D. N.

    2016-12-01

    The Earth System Grid Federation (ESGF) is primarily funded by the Department of Energy's (DOE's) Office of Science (the Office of Biological and Environmental Research [BER] Climate Data Informatics Program and the Office of Advanced Scientific Computing Research Next Generation Network for Science Program), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), and the National Science Foundation (NSF), the European Infrastructure for the European Network for Earth System Modeling (IS-ENES), and the Australian National University (ANU). Support also comes from other U.S. federal and international agencies. The federation works across multiple worldwide data centers and spans seven international network organizations to provide users with the ability to access, analyze, and visualize data using a globally federated collection of networks, computers, and software. Its architecture employs a series of geographically distributed peer nodes that are independently administered and united by common federation protocols and application programming interfaces (APIs). The full ESGF infrastructure has now been adopted by multiple Earth science projects and allows access to petabytes of geophysical data, including the Coupled Model Intercomparison Project (CMIP; output used by the Intergovernmental Panel on Climate Change assessment reports), multiple model intercomparison projects (MIPs; endorsed by the World Climate Research Programme [WCRP]), and the Accelerated Climate Modeling for Energy (ACME; ESGF is included in the overarching ACME workflow process to store model output). ESGF is a successful example of integration of disparate open-source technologies into a cohesive functional system that serves the needs the global climate science community. Data served by ESGF includes not only model output but also observational data from satellites and instruments, reanalysis, and generated images.

  18. Global Volcano Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Volcano Mortality Risks and Distribution is a 2.5 minute grid representing global volcano mortality risks. The data set was constructed using historical...

  19. Global Flood Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Flood Mortality Risks and Distribution is a 2.5 minute grid of global flood mortality risks. Gridded Population of the World, Version 3 (GPWv3) data provided...

  20. Global Multihazard Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Multihazard Mortality Risks and Distribution is a 2.5 minute grid identifying and characterizing the nature of multihazard risk at the global scale. For this...

  1. Global Earthquake Hazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Hazard Frequency and Distribution is a 2.5 by 2.5 minute global utilizing Advanced National Seismic System (ANSS) Earthquake Catalog data of actual...

  2. Global Drought Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Drought Mortality Risks and Distribution is a 2.5 minute grid of global drought mortality risks. Gridded Population of the World, Version 3 (GPWv3) data...

  3. Global Cyclone Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Cyclone Mortality Risks and Distribution is a 2.5 by 2.5 minute grid of global cyclone mortality risks. Gridded Population of the World (GPW) Version 3 (beta)...

  4. Global Landslide Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Landslide Mortality Risks and Distribution is a 2.5 minute grid of global landslide mortality risks. Gridded Population of the World, Version 3 (GPWv3) data...

  5. Global Earthquake Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Mortality Risks and Distribution is a 2.5 minute grid of global earthquake mortality risks. Gridded Population of the World, Version 3 (GPWv3) data...

  6. Global Cyclone Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Cyclone Mortality Risks and Distribution is a 2.5 minute grid of global cyclone mortality risks. Gridded Population of the World, Version 3 (GPWv3) data...

  7. Global Flood Hazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Flood Hazard Frequency and Distribution is a 2.5 minute grid derived from a global listing of extreme flood events between 1985 and 2003 (poor or missing data...

  8. Physician Assistants and the Expanding Global Health-Care Workforce.

    Science.gov (United States)

    Rick, Tara J; Ballweg, Ruth

    2017-09-01

    The physician assistant and other types of medical providers with accelerated and focused training were developed to serve the specific health-care needs of individual countries. They have an important role in providing care globally in response to physician shortages. Working in over 50 nations, these clinicians increase access to team-based health care. This perspective explores the successes and challenges of these professionals as an international community. Steps are proposed to increase global awareness and acceptance of these professionals including platforms to increase discussion, scholarly activity, and collaboration.

  9. Beyond Dualism: Expanded Understandings of Religion and Global Justice

    NARCIS (Netherlands)

    Wilson, Erin

    2010-01-01

    The world’s religions have strong traditions of contributing to theories and practices around justice. Recent debates on global justice within International Relations (IR), however, have largely overlooked possible contributions from religion. This article explores why religion is neglected, despite

  10. INTRODUCTION The global HIV epidemic continues to expand with ...

    African Journals Online (AJOL)

    the HIV disease itself.9 During pregnancy, dosing must be taken into consideration as blood volume and volume of distribution changes during pregnancy. In addition, there are potential toxic drug effects on the ... myopathy may dictate change of anesthetic techniques. Anemia and thrombocytopenia are major toxic side.

  11. Expanding Distribution of Lethal Amphibian Fungus Batrachochytrium salamandrivorans in Europe

    OpenAIRE

    Spitzen-van der Sluijs, Annemarieke; Asselberghs, Johan; Martel, An; Bales, Emma K.; Beukema, Wouter; Bletz, Molly C.; Dalbeck, Lutz; Goverse, Edo; Kerres, Alexander; Kinet, Thierry; Kirst, Kai; Laudelout, Arnaud; Marin da Fonte, Luis F.; Nöllert, Andreas; Ohlhoff, Dagmar

    2016-01-01

    Emerging fungal diseases can drive amphibian species to local extinction. During 2010-2016, we examined 1,921 urodeles in 3 European countries. Presence of the chytrid fungus Batrachochytrium salamandrivorans at new locations and in urodeles of different species expands the known geographic and host range of the fungus and underpins its imminent threat to biodiversity.

  12. Expanding Distribution of Lethal Amphibian Fungus Batrachochytrium salamandrivorans in Europe.

    Science.gov (United States)

    Spitzen-van der Sluijs, Annemarieke; Martel, An; Asselberghs, Johan; Bales, Emma K; Beukema, Wouter; Bletz, Molly C; Dalbeck, Lutz; Goverse, Edo; Kerres, Alexander; Kinet, Thierry; Kirst, Kai; Laudelout, Arnaud; Marin da Fonte, Luis F; Nöllert, Andreas; Ohlhoff, Dagmar; Sabino-Pinto, Joana; Schmidt, Benedikt R; Speybroeck, Jeroen; Spikmans, Frank; Steinfartz, Sebastian; Veith, Michael; Vences, Miguel; Wagner, Norman; Pasmans, Frank; Lötters, Stefan

    2016-07-01

    Emerging fungal diseases can drive amphibian species to local extinction. During 2010-2016, we examined 1,921 urodeles in 3 European countries. Presence of the chytrid fungus Batrachochytrium salamandrivorans at new locations and in urodeles of different species expands the known geographic and host range of the fungus and underpins its imminent threat to biodiversity.

  13. Expanding Distribution of Lethal Amphibian Fungus Batrachochytrium salamandrivorans in Europe

    OpenAIRE

    Spitzen-van der Sluijs, Annemarieke; Martel, An; et al, ...; Schmidt, B R

    2016-01-01

    Emerging fungal diseases can drive amphibian species to local extinction. During 2010–2016, we examined 1,921 urodeles in 3 European countries. Presence of the chytrid fungus Batrachochytrium salamandrivorans at new locations and in urodeles of different species expands the known geographic and host range of the fungus and underpins its imminent threat to biodiversity.

  14. Inflammatory Bowel Disease: An Expanding Global Health Problem

    Science.gov (United States)

    M’Koma, Amosy E.

    2013-01-01

    This review provides a summary of the global epidemiology of inflammatory bowel diseases (IBD). It is now clear that IBD is increasing worldwide and has become a global emergence disease. IBD, which includes Crohn’s disease (CD) and ulcerative colitis (UC), has been considered a problem in industrial-urbanized societies and attributed largely to a Westernized lifestyle and other associated environmental factors. Its incidence and prevalence in developing countries is steadily rising and has been attributed to the rapid modernization and Westernization of the population. There is a need to reconcile the most appropriate treatment for these patient populations from the perspectives of both disease presentation and cost. In the West, biological agents are the fastest-growing segment of the prescription drug market. These agents cost thousands of dollars per patient per year. The healthcare systems, and certainly the patients, in developing countries will struggle to afford such expensive treatments. The need for biological therapy will inevitably increase dramatically, and the pharmaceutical industry, healthcare providers, patient advocate groups, governments and non-governmental organizations should come to a consensus on how to handle this problem. The evidence that IBD is now affecting a much younger population presents an additional concern. Meta-analyses conducted in patients acquiring IBD at a young age also reveals a trend for their increased risk of developing colorectal cancer (CRC), since the cumulative incidence rates of CRC in IBD-patients diagnosed in childhood are higher than those observed in adults. In addition, IBD-associated CRC has a worse prognosis than sporadic CRC, even when the stage at diagnosis is taken into account. This is consistent with additional evidence that IBD negatively impacts CRC survival. A continuing increase in IBD incidence worldwide associated with childhood-onset of IBD coupled with the diseases’ longevity and an increase

  15. Global Volcano Hazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Volcano Hazard Frequency and Distribution is a 2.5 minute gridded data set based upon the National Geophysical Data Center (NGDC) Volcano Database spanning...

  16. Global Earthquake Hazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Hazard Frequency and Distribution is a 2.5 minute grid utilizing Advanced National Seismic System (ANSS) Earthquake Catalog data of actual...

  17. Global Earthquake Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Earthquake Hazard Frequency and Distribution is a 2.5 minute grid utilizing Advanced National Seismic System (ANSS) Earthquake Catalog data of actual...

  18. Global Cyclone Hazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Cyclone Hazard Frequency and Distribution is a 2.5 minute grid based on more than 1,600 storm tracks for the period 1 January 1980 through 31 December 2000...

  19. Global Drought Hazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Drought Hazard Frequency and Distribution is a 2.5 minute grid based upon the International Research Institute for Climate Prediction's (IRI) Weighted Anomaly...

  20. Understanding Microplastic Distribution: A Global Citizen Monitoring Effort

    Science.gov (United States)

    Barrows, A.

    2016-02-01

    Understanding distribution and abundance of microplastics in the world's oceans will continue to help inform global law-making. Through recruiting and training over 500 volunteers our study has collected over 1000 samples from remote and populated areas world-wide. Samples include water collected at the sea surface and throughout the water column. Surface to depth sampling has provided insight into vertical plastic distribution. The development of unique field and laboratory methodology has enabled plastics to be quantified down to 50 µm. In 2015, the study expanded to include global freshwater systems. By understanding plastic patterns, distribution and concentration in large and small watersheds we will better understand how freshwater systems are contributing to marine microplastic pollution.

  1. A distributed Kalman filter with global covariance

    NARCIS (Netherlands)

    Sijs, J.; Lazar, M.

    2011-01-01

    Most distributed Kalman filtering (DKF) algorithms for sensor networks calculate a local estimate of the global state-vector in each node. An important challenge within distributed estimation is that all sensors in the network contribute to the local estimate in each node. In this paper, a novel DKF

  2. A Global Enviromental Data Distribution System

    OpenAIRE

    Walker, Philip

    1991-01-01

    This paper describes a global environmental data distribution system (GEDDS) which uses a single small satellite operating in a low polar orbit. The satellite collects environmental data from remotely located instrumentation platforms and distributes it to research laboratories and other interested organizations virtually anywhere in the world. A command link also allows principal investigators to control and calibrate platform instruments on a daily basis directly from their laboratory or of...

  3. Global Cyclone Hazard Frequency and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Cyclone Hazard Frequency and Distribution is a 2.5 by 2.5 minute grid based on more than 1,600 storm tracks for the period 1 January 1980 through 31 December...

  4. Revised spatially distributed global livestock emissions

    Science.gov (United States)

    Asrar, G.; Wolf, J.; West, T. O.

    2015-12-01

    Livestock play an important role in agricultural carbon cycling through consumption of biomass and emissions of methane. Quantification and spatial distribution of methane and carbon dioxide produced by livestock is needed to develop bottom-up estimates for carbon monitoring. These estimates serve as stand-alone international emissions estimates, as input to global emissions modeling, and as comparisons or constraints to flux estimates from atmospheric inversion models. Recent results for the US suggest that the 2006 IPCC default coefficients may underestimate livestock methane emissions. In this project, revised coefficients were calculated for cattle and swine in all global regions, based on reported changes in body mass, quality and quantity of feed, milk production, and management of living animals and manure for these regions. New estimates of livestock methane and carbon dioxide emissions were calculated using the revised coefficients and global livestock population data. Spatial distribution of population data and associated fluxes was conducted using the MODIS Land Cover Type 5, version 5.1 (i.e. MCD12Q1 data product), and a previously published downscaling algorithm for reconciling inventory and satellite-based land cover data at 0.05 degree resolution. Preliminary results for 2013 indicate greater emissions than those calculated using the IPCC 2006 coefficients. Global total enteric fermentation methane increased by 6%, while manure management methane increased by 38%, with variation among species and regions resulting in improved spatial distributions of livestock emissions. These new estimates of total livestock methane are comparable to other recently reported studies for the entire US and the State of California. These new regional/global estimates will improve the ability to reconcile top-down and bottom-up estimates of methane production as well as provide updated global estimates for use in development and evaluation of Earth system models.

  5. Distributive Justice: An Ethical Priority in Global Palliative Care.

    Science.gov (United States)

    Hadler, Rachel A; Rosa, William E

    2017-12-27

    Providing care to cancer patients in resource-poor settings often demands complex trade-offs regarding resource allocation. It is estimated that over 60% of all cancer deaths worldwide occur in low- and middle-income countries (LMICs), where channels to care and appropriate symptom management interventions are overstressed or obsolete. Concepts of distributive justice underlie much of global health policy. As appetites for expanding global palliative care services increase so do questions of fair and culturally appropriate distribution. The ethical principle of distributive justice underpins questions of resource allocation at a fundamental level. One of the most challenging concepts for healthcare workers immersing in cross-cultural contexts is the idea that ethics are somewhat malleable; they shape and are shaped by the unique sociopolitical, economic, intracultural, and power dynamics of a particular setting. In this article, we use the case of a young woman diagnosed with terminal cancer in an underserved community in rural Uganda to illustrate the conflicting concepts of fairness which dictate distribution of scarce resources in LMICs. Notions of distributive justice vary across cultural, societal and even individual norms, with some definitions allowing for discrimination based on merit or need. Resource allocation in the absence of cultural humility or a genuine willingness to understand decision-making priorities in a given culture can contribute to inequity and may have harmful consequences. Copyright © 2017. Published by Elsevier Inc.

  6. Global distribution of fluvial channels on Titan

    Science.gov (United States)

    Langhans, M.; Jaumann, R.; Stephan, K.; Brown, R. H.; Buratti, B. J.; Clark, R.; Baines, K. H.; Nicholson, P. D.; Lorenz, R. D.

    2009-04-01

    The presence of fluvial erosion on Titan's surface is an obvious analogy to Earth. This study investigates the global distribution of fluvial valley systems on Titan. Based on Cassini-RADAR-data we mapped the allocation of channels, their appropriate flow direction and morphological properties. A great variety of morphological valley types ranges from dendritic valleys that certainly developed from precipitation to a more canyon-like valley type whose development is possibly supported by groundwater release. Another type of fluvial valleys resembles terrestrial wadis that evolved as a result of precipitation separated by long-term intervals of dry periods. Furthermore, based on a global Cassini-VIMS-mosaic the allocation of fluvial channels was determined with respect to spectral units. Based on the spectral signature in the infrared methane windows - expressed as VIMS wavelength ratios composed to a color image (RGB) - three major units can be distinguished: whitish material which is mainly distributed in the topographically high areas indicating equal reflectivity in all atmospheric windows; bluish material that exhibits a higher reflectivity at shorter atmospheric wavelength windows implying a clear spectral separation from the whitish material, and brownish material characterized by a higher reflectivity in the longer wavelength atmospheric windows that correlates with dunes. The majority of channels are exposed on the bright surface unit while just a few percent of channels are located on the blue and brown surface unit, respectively. Fluvial incision has shaped Titan's surface globally. Nevertheless, from a morphological point of view as well as concerning the associated VIMS-unit fluvial shaping is not uniform. The global distribution of channels provides unique information about environmental conditions and processes forming Titan's surface. However, to date just 20% of Titans surface are covered with high resolution data, thus, the current results can only

  7. Globally distributed software defined storage (proposal)

    Science.gov (United States)

    Shevel, A.; Khoruzhnikov, S.; Grudinin, V.; Sadov, O.; Kairkanov, A.

    2017-10-01

    The volume of the coming data in HEP is growing. The volume of the data to be held for a long time is growing as well. Large volume of data – big data – is distributed around the planet. The methods, approaches how to organize and manage the globally distributed data storage are required. The distributed storage has several examples for personal needs like own-cloud.org, pydio.com, seafile.com, sparkleshare.org. For enterprise-level there is a number of systems: SWIFT - distributed storage systems (part of Openstack), CEPH and the like which are mostly object storage. When several data center’s resources are integrated, the organization of data links becomes very important issue especially if several parallel data links between data centers are used. The situation in data centers and in data links may vary each hour. All that means each part of distributed data storage has to be able to rearrange usage of data links and storage servers in each data center. In addition, for each customer of distributed storage different requirements could appear. The above topics are planned to be discussed in data storage proposal.

  8. The global age distribution of granitic pegmatites

    Science.gov (United States)

    McCauley, Andrew; Bradley, Dwight C.

    2014-01-01

    An updated global compilation of 377 new and previously published ages indicates that granitic pegmatites range in age from Mesoarchean to Neogene and have a semi-periodic age distribution. Undivided granitic pegmatites show twelve age maxima: 2913, 2687, 2501, 1853, 1379, 1174, 988, 525, 483, 391, 319, and 72 Ma. These peaks correspond broadly with various proxy records of supercontinent assembly, including the age distributions of granites, detrital zircon grains, and passive margins. Lithium-cesium-tantalum (LCT) pegmatites have a similar age distribution to the undivided granitic pegmatites, with maxima at 2638, 1800, 962, 529, 485, 371, 309, and 274 Ma. Lithium and Ta resources in LCT pegmatites are concentrated in the Archean and Phanerozoic. While there are some Li resources from the Proterozoic, the dominantly bimodal distribution of resources is particularly evident for Ta. This distribution is similar to that of orogenic gold deposits, and has been interpreted to reflect the preservation potential of the orogenic belts where these deposits are formed. Niobium-yttrium-fluorine (NYF) pegmatites show similar age distributions to LCT pegmatites, but with a strong maximum at ca. 1000 Ma.

  9. Distribution and Causes of Global Forest Fragmentation

    Directory of Open Access Journals (Sweden)

    Timothy G. Wade

    2003-12-01

    Full Text Available Because human land uses tend to expand over time, forests that share a high proportion of their borders with anthropogenic uses are at higher risk of further degradation than forests that share a high proportion of their borders with non-forest, natural land cover (e.g., wetland. Using 1-km advanced very high resolution radiometer (AVHRR satellite-based land cover, we present a method to separate forest fragmentation into natural and anthropogenic components, and report results for all inhabited continents summarized by World Wildlife Fund biomes. Globally, over half of the temperate broadleaf and mixed forest biome and nearly one quarter of the tropical rainforest biome have been fragmented or removed by humans, as opposed to only 4% of the boreal forest. Overall, Europe had the most human-caused fragmentation and South America the least. This method may allow for improved risk assessments and better targeting for protection and remediation by identifying areas with high amounts of human-caused fragmentation.

  10. Global Normal Form and Asymptotic Spectral Gap for Open Partially Expanding Maps

    Science.gov (United States)

    Faure, Frédéric; Weich, Tobias

    2017-10-01

    We consider a R -extension of one dimensional uniformly expanding open dynamical systems and prove a new explicit estimate for the asymptotic spectral gap. To get these results, we use a new application of a "global normal form" for the dynamical system, a "semiclassical expression beyond the Ehrenfest time" that expresses the transfer operator at large time as a sum over rank one operators (each is associated to one orbit). In this paper we establish the validity of the so-called "diagonal approximation" up to twice the local Ehrenfest time.

  11. Mapping the global distribution of livestock.

    Directory of Open Access Journals (Sweden)

    Timothy P Robinson

    Full Text Available Livestock contributes directly to the livelihoods and food security of almost a billion people and affects the diet and health of many more. With estimated standing populations of 1.43 billion cattle, 1.87 billion sheep and goats, 0.98 billion pigs, and 19.60 billion chickens, reliable and accessible information on the distribution and abundance of livestock is needed for a many reasons. These include analyses of the social and economic aspects of the livestock sector; the environmental impacts of livestock such as the production and management of waste, greenhouse gas emissions and livestock-related land-use change; and large-scale public health and epidemiological investigations. The Gridded Livestock of the World (GLW database, produced in 2007, provided modelled livestock densities of the world, adjusted to match official (FAOSTAT national estimates for the reference year 2005, at a spatial resolution of 3 minutes of arc (about 5×5 km at the equator. Recent methodological improvements have significantly enhanced these distributions: more up-to date and detailed sub-national livestock statistics have been collected; a new, higher resolution set of predictor variables is used; and the analytical procedure has been revised and extended to include a more systematic assessment of model accuracy and the representation of uncertainties associated with the predictions. This paper describes the current approach in detail and presents new global distribution maps at 1 km resolution for cattle, pigs and chickens, and a partial distribution map for ducks. These digital layers are made publically available via the Livestock Geo-Wiki (http://www.livestock.geo-wiki.org, as will be the maps of other livestock types as they are produced.

  12. Global Expanded Nutrient Supply (GENuS) Model: A New Method for Estimating the Global Dietary Supply of Nutrients.

    Science.gov (United States)

    Smith, Matthew R; Micha, Renata; Golden, Christopher D; Mozaffarian, Dariush; Myers, Samuel S

    2016-01-01

    Insufficient data exist for accurate estimation of global nutrient supplies. Commonly used global datasets contain key weaknesses: 1) data with global coverage, such as the FAO food balance sheets, lack specific information about many individual foods and no information on micronutrient supplies nor heterogeneity among subnational populations, while 2) household surveys provide a closer approximation of consumption, but are often not nationally representative, do not commonly capture many foods consumed outside of the home, and only provide adequate information for a few select populations. Here, we attempt to improve upon these datasets by constructing a new model--the Global Expanded Nutrient Supply (GENuS) model--to estimate nutrient availabilities for 23 individual nutrients across 225 food categories for thirty-four age-sex groups in nearly all countries. Furthermore, the model provides historical trends in dietary nutritional supplies at the national level using data from 1961-2011. We determine supplies of edible food by expanding the food balance sheet data using FAO production and trade data to increase food supply estimates from 98 to 221 food groups, and then estimate the proportion of major cereals being processed to flours to increase to 225. Next, we estimate intake among twenty-six demographic groups (ages 20+, both sexes) in each country by using data taken from the Global Dietary Database, which uses nationally representative surveys to relate national averages of food consumption to individual age and sex-groups; for children and adolescents where GDD data does not yet exist, average calorie-adjusted amounts are assumed. Finally, we match food supplies with nutrient densities from regional food composition tables to estimate nutrient supplies, running Monte Carlo simulations to find the range of potential nutrient supplies provided by the diet. To validate our new method, we compare the GENuS estimates of nutrient supplies against independent

  13. Global distribution of lunar impact melt flows

    Science.gov (United States)

    Neish, C. D.; Madden, J.; Carter, L. M.; Hawke, B. R.; Giguere, T.; Bray, V. J.; Osinski, G. R.; Cahill, J. T. S.

    2014-09-01

    In this study, we analyzed the distribution and properties of 146 craters with impact melt deposits exterior to their rims. Many of these craters were only recently discovered due to their unusual radar properties in the near-global Mini-RF data set. We find that most craters with exterior deposits of impact melt are small, ⩽20 km, and that the smallest craters have the longest melt flows relative to their size. In addition, exterior deposits of impact melt are more common in the highlands than the mare. This may be the result of differing target properties in the highlands and mare, the difference in titanium content, or the greater variation of topography in the highlands. We find that 80% of complex craters and 60% of simple craters have melt directions that are coincident or nearly coincident with the lowest point in their rim, implying that pre-existing topography plays a dominant role in melt emplacement. This is likely due to movement during crater modification (complex craters) or breached crater rims (simple craters). We also find that impact melt flows have very high circular polarization ratios compared to other features on the Moon. This suggests that their surfaces are some of the roughest material on the Moon at the centimeter to decimeter scale, even though they appear smooth at the meter scale.

  14. Factors that Inhibit Globally Distributed Software Development Teams

    OpenAIRE

    Deanna House

    2013-01-01

    Globally distributed teams can frequently have problems specifically related to the distance and differences among team members. This paper synthesizes literature related to globally distributed software development teams to find the factors that inhibit team success. This research indicates that cultural differences, trust, communication, shared mental models, temporal agility, and work transitions can all cause problems on globally distributed software development teams. This research ca...

  15. Spreading vs. Rifting as modes of extensional tectonics on the globally expanded Ganymede

    Science.gov (United States)

    Pizzi, Alberto; di Domenica, Alessandra; Komatsu, Goro; Cofano, Alessandra; Mitri, Giuseppe; Bruzzone, Lorenzo

    2017-05-01

    The formation of Ganymede's sulci is likely related to extensional tectonics that affected this largest icy satellite of Jupiter. Through geometric and structural analyses we reconstructed the pre-deformed terrains and we recognized two different modes of extension associated with sulci. In the first mode, smooth sulci constitute spreading centers between two dark terrain plates, similar to the fast oceanic spreading centers on Earth. Here extension is primarily accommodated by crustal accretion of newly formed icy crust. In the second mode, dark terrain extension is mainly accommodated by swaths of normal fault systems analogous to Earth's continental crustal rifts. A comparison with terrestrial extensional analogues, based on the fault displacement/length (Dmax/L) ratio, spacing and morphology, showed that magmato-tectonic spreading centers and continental crustal rifts on Earth follow the same relative patterns observed on Ganymede. Our results suggest that the amount of extensional strain may have previously been underestimated since the occurrence of spreading centers may have played a major role in the tectonic evolution of the globally expanded Ganymede. We also discuss a possible model for the origin of the different modes of extension in the context of the global expansion of the satellite.

  16. Global resilience analysis of water distribution systems.

    Science.gov (United States)

    Diao, Kegong; Sweetapple, Chris; Farmani, Raziyeh; Fu, Guangtao; Ward, Sarah; Butler, David

    2016-12-01

    Evaluating and enhancing resilience in water infrastructure is a crucial step towards more sustainable urban water management. As a prerequisite to enhancing resilience, a detailed understanding is required of the inherent resilience of the underlying system. Differing from traditional risk analysis, here we propose a global resilience analysis (GRA) approach that shifts the objective from analysing multiple and unknown threats to analysing the more identifiable and measurable system responses to extreme conditions, i.e. potential failure modes. GRA aims to evaluate a system's resilience to a possible failure mode regardless of the causal threat(s) (known or unknown, external or internal). The method is applied to test the resilience of four water distribution systems (WDSs) with various features to three typical failure modes (pipe failure, excess demand, and substance intrusion). The study reveals GRA provides an overview of a water system's resilience to various failure modes. For each failure mode, it identifies the range of corresponding failure impacts and reveals extreme scenarios (e.g. the complete loss of water supply with only 5% pipe failure, or still meeting 80% of demand despite over 70% of pipes failing). GRA also reveals that increased resilience to one failure mode may decrease resilience to another and increasing system capacity may delay the system's recovery in some situations. It is also shown that selecting an appropriate level of detail for hydraulic models is of great importance in resilience analysis. The method can be used as a comprehensive diagnostic framework to evaluate a range of interventions for improving system resilience in future studies. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Gridded Species Distribution, Version 1: Global Amphibians Presence Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Amphibians Presence Grids of the Gridded Species Distribution, Version 1 is a reclassified version of the original grids of amphibian species distribution...

  18. New species of Heteropathes (Anthozoa: Antipatharia) expands genus distribution to the NE Atlantic.

    Science.gov (United States)

    De Matos, Valentina; Braga-Henriques, Andreia; Santos, Ricardo S; Ribeiro, Pedro A

    2014-07-03

    Heteropathes opreski, a new antipatharian species from the northern border of the Oceanographer Fracture Zone is here described and illustrated. An emended diagnosis of the genus and a dichotomous key containing the four Heteropathes species are presented. This species is unique in that it forms smaller colonies compared to the other species in the genus, with some of the lateral pinnules presenting a small ramified subpinnule. Additionally, the polypar spines found on the lateral pinnules are the highest so far recorded in the genus. This record greatly expands the known distribution of this genus, as it was not previously reported to occur in the Northeastern Atlantic.

  19. Management of Globally Distributed Component-Based Software Development Projects

    NARCIS (Netherlands)

    J. Kotlarsky (Julia)

    2005-01-01

    textabstractGlobally Distributed Component-Based Development (GD CBD) is expected to become a promising area, as increasing numbers of companies are setting up software development in a globally distributed environment and at the same time are adopting CBD methodologies. Being an emerging area, the

  20. Global marine plankton functional type biomass distributions : Phaeocystis spp

    NARCIS (Netherlands)

    Vogt, M.; O'Brien, C.; Peloquin, J.; Schoemann, V.; Breton, E.; Estrada, M.; Gibson, J.; Karentz, D.; Van Leeuwe, M. A.; Stefels, J.; Widdicombe, C.; Peperzak, L.

    2012-01-01

    The planktonic haptophyte Phaeocystis has been suggested to play a fundamental role in the global biogeochemical cycling of carbon and sulphur, but little is known about its global biomass distribution. We have collected global microscopy data of the genus Phaeocystis and converted abundance data to

  1. Using E-markets for Globally Distributed Work

    NARCIS (Netherlands)

    van Hillegersberg, Jos; Amrit, Chintan Amrit; Oshri, Ilan; Kotlarsky, Julia; Willcocks, Leslie P.

    2015-01-01

    For over a decade, dedicated E-markets have been facilitating globally distributed systems development by enhancing the traditionally high-risk global sourcing processes. At the same time, the success and potential of E-markets for sourcing project globally can be questioned, as E-markets embody a

  2. Global distribution of novel rhinovirus genotype

    DEFF Research Database (Denmark)

    Briese, Thomas; Renwick, Neil; Venter, Marietjie

    2008-01-01

    Global surveillance for a novel rhinovirus genotype indicated its association with community outbreaks and pediatric respiratory disease in Africa, Asia, Australia, Europe, and North America. Molecular dating indicates that these viruses have been circulating for at least 250 years Udgivelsesdato...

  3. Global distribution of novel rhinovirus genotype

    DEFF Research Database (Denmark)

    Briese, Thomas; Renwick, Neil; Venter, Marietjie

    2008-01-01

    Global surveillance for a novel rhinovirus genotype indicated its association with community outbreaks and pediatric respiratory disease in Africa, Asia, Australia, Europe, and North America. Molecular dating indicates that these viruses have been circulating for at least 250 years....

  4. Global distribution of novel rhinovirus genotype

    DEFF Research Database (Denmark)

    Briese, Thomas; Renwick, Neil; Venter, Marietjie

    2008-01-01

    Global surveillance for a novel rhinovirus genotype indicated its association with community outbreaks and pediatric respiratory disease in Africa, Asia, Australia, Europe, and North America. Molecular dating indicates that these viruses have been circulating for at least 250 years.......Global surveillance for a novel rhinovirus genotype indicated its association with community outbreaks and pediatric respiratory disease in Africa, Asia, Australia, Europe, and North America. Molecular dating indicates that these viruses have been circulating for at least 250 years....

  5. Orchestration of Globally Distributed Knowledge for Innovation in Multinational Companies

    DEFF Research Database (Denmark)

    Sajadirad, Solmaz; Lassen, Astrid Heidemann

    2017-01-01

    Conducting a multiple-case study in five companies from Danish industry, this paper explores how multinational companies orchestrate knowledge from their globally distributed subsidiaries for innovation. Comparisons of knowledge orchestration within headquarter and subsidiaries for improvement...... globally distributed knowledge. This study contributes to the understanding of knowledge orchestration between headquarter and distributed subsidiaries in multinational companies and how it is related to innovation. Specifically, this paper has important implications regarding the use of inter-firm objects...

  6. Contracting, equal, and expanding learning schedules: the optimal distribution of learning sessions depends on retention interval.

    Science.gov (United States)

    Küpper-Tetzel, Carolina E; Kapler, Irina V; Wiseheart, Melody

    2014-07-01

    In laboratory and applied learning experiments, researchers have extensively investigated the optimal distribution of two learning sessions (i.e., initial learning and one relearning session) for the learning of verbatim materials. However, research has not yet provided a satisfying and conclusive answer to the optimal scheduling of three learning sessions (i.e., initial learning and two relearning sessions) across educationally relevant time intervals. Should the to-be-learned material be repeated at decreasing intervals (contracting schedule), constant intervals (equal schedule), or increasing intervals (expanding schedule) between learning sessions? Different theories and memory models (e.g., study-phase retrieval theory, contextual variability theory, ACT-R, and the Multiscale Context Model) make distinct predictions about the optimal learning schedule. We discuss the extant theories and derive clear predictions from each of them. To test these predictions empirically, we conducted an experiment in which participants studied and restudied paired associates with a contracting, equal, or expanding learning schedule. Memory performance was assessed immediately, 1 day, 7 days, or 35 days later with free- and cued-recall tests. Our results revealed that the optimal learning schedule is conditional on the length of the retention interval: A contracting learning schedule was beneficial for retention intervals up to 7 days, but both equal and expanding learning schedules were better for a long retention interval of 35 days. Our findings can be accommodated best by the contextual variability theory and indicate that revisions are needed to existing memory models. Our results are practically relevant, and their implications for real-world learning are discussed.

  7. Global diversity and distribution of macrofungi

    Science.gov (United States)

    Gregory M. Mueller; John P. Schmit; Patrick R. Leacock; Bart Buyck; Joaquin Cifuentes; Dennis E. Desjardin; Roy E. Halling; Kurt Hjortstam; Teresa Iturriaga; Karl-Henrik Larsson; D. Jean Lodge; Tom W. May; David Minter; Mario Rajchenberg; Scott A. Redhead; Leif Ryvarden; James M. Trappe; Roy Watling; Qiuxin Wu

    2007-01-01

    Data on macrofungal diversity and distribution patterns were compiled for major geographical regions of the world. Macrofungi are defined here to include ascomycetes and basidiomycetes with large, easily observed spore-bearing structures that form above or below ground. Each coauthor either provided data on a particular taxonomic group of macrofungi or information on...

  8. Global Poverty : Scraping distributional data from the World Bank

    NARCIS (Netherlands)

    Moatsos, M.

    2016-01-01

    The problem of measuring global poverty consistently is addressed using a family of bare bones consumption baskets (BBB). This methodology pinpoints equivalent levels of welfare, both internationally and intertemporally. Naturally, in calculating poverty rates the household consumption distributions

  9. Gridded Species Distribution: Global Amphibian Richness Grids, 2015 Release

    Data.gov (United States)

    National Aeronautics and Space Administration — The 2015 Release of the Global Amphibian Richness Grids data set of the Gridded Species Distribution collection are aggregations of the presence grids data for the...

  10. Gridded Species Distribution, Version 1: Global Amphibians Original Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Amphibians Original Grids of the Gridded Species Distribution, Version 1 are converted 1- kilometer grid cell data available in the Geographic Coordinate...

  11. Gridded Species Distribution, Version 1: Global Amphibians Family Richness Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Amphibians Family Richness Grids of the Gridded Species Distribution, Version 1 are aggregations of the presence grids data at the family level. They are...

  12. Gridded Species Distribution: Global Mammal Richness Grids, 2015 Release

    Data.gov (United States)

    National Aeronautics and Space Administration — The 2015 Release of the Global Mammal Richness Grids data set of the Gridded Species Distribution collection are aggregations of the presence grids data for the...

  13. Global tropospheric hydroxyl distribution, budget and reactivity

    Science.gov (United States)

    Lelieveld, Jos; Gromov, Sergey; Pozzer, Andrea; Taraborrelli, Domenico

    2016-10-01

    The self-cleaning or oxidation capacity of the atmosphere is principally controlled by hydroxyl (OH) radicals in the troposphere. Hydroxyl has primary (P) and secondary (S) sources, the former mainly through the photodissociation of ozone, the latter through OH recycling in radical reaction chains. We used the recent Mainz Organics Mechanism (MOM) to advance volatile organic carbon (VOC) chemistry in the general circulation model EMAC (ECHAM/MESSy Atmospheric Chemistry) and show that S is larger than previously assumed. By including emissions of a large number of primary VOC, and accounting for their complete breakdown and intermediate products, MOM is mass-conserving and calculates substantially higher OH reactivity from VOC oxidation compared to predecessor models. Whereas previously P and S were found to be of similar magnitude, the present work indicates that S may be twice as large, mostly due to OH recycling in the free troposphere. Further, we find that nighttime OH formation may be significant in the polluted subtropical boundary layer in summer. With a mean OH recycling probability of about 67 %, global OH is buffered and not sensitive to perturbations by natural or anthropogenic emission changes. Complementary primary and secondary OH formation mechanisms in pristine and polluted environments in the continental and marine troposphere, connected through long-range transport of O3, can maintain stable global OH levels.

  14. Aeromonas update: new species and global distribution.

    Science.gov (United States)

    Carnahan, A M; Joseph, S W

    1991-05-15

    There are currently eight proposed or validated Aeromonas spp. of which five have been implicated in human disease: A. hydrophila, A. sobria, A. caviae, A. veronii, and A. schubertii. Recent studies have extended the geographic distribution and source of isolation of the newer species and resulted in the possibility of two new species, A. jandaei and A. trota, from diarrheal, wound, blood and environmental sources.

  15. Strongyloides stercoralis: Global Distribution and Risk Factors.

    Directory of Open Access Journals (Sweden)

    Fabian Schär

    Full Text Available BACKGROUND: The soil-transmitted threadworm, Strongyloides stercoralis, is one of the most neglected among the so-called neglected tropical diseases (NTDs. We reviewed studies of the last 20 years on S. stercoralis's global prevalence in general populations and risk groups. METHODS/PRINCIPAL FINDINGS: A literature search was performed in PubMed for articles published between January 1989 and October 2011. Articles presenting information on infection prevalence were included. A Bayesian meta-analysis was carried out to obtain country-specific prevalence estimates and to compare disease odds ratios in different risk groups taking into account the sensitivities of the diagnostic methods applied. A total of 354 studies from 78 countries were included for the prevalence calculations, 194 (62.4% were community-based studies, 121 (34.2% were hospital-based studies and 39 (11.0% were studies on refugees and immigrants. World maps with country data are provided. In numerous African, Asian and South-American resource-poor countries, information on S. stercoralis is lacking. The meta-analysis showed an association between HIV-infection/alcoholism and S. stercoralis infection (OR: 2.17 BCI: 1.18-4.01; OR: 6.69; BCI: 1.47-33.8, respectively. CONCLUSIONS: Our findings show high infection prevalence rates in the general population in selected countries and geographical regions. S. stercoralis infection is prominent in several risk groups. Adequate information on the prevalence is still lacking from many countries. However, current information underscore that S. stercoralis must not be neglected. Further assessments in socio-economic and ecological settings are needed and integration into global helminth control is warranted.

  16. Strongyloides stercoralis: Global Distribution and Risk Factors

    Science.gov (United States)

    Schär, Fabian; Trostdorf, Ulf; Giardina, Federica; Khieu, Virak; Muth, Sinuon; Marti, Hanspeter; Vounatsou, Penelope; Odermatt, Peter

    2013-01-01

    Background The soil-transmitted threadworm, Strongyloides stercoralis, is one of the most neglected among the so-called neglected tropical diseases (NTDs). We reviewed studies of the last 20 years on S. stercoralis's global prevalence in general populations and risk groups. Methods/Principal Findings A literature search was performed in PubMed for articles published between January 1989 and October 2011. Articles presenting information on infection prevalence were included. A Bayesian meta-analysis was carried out to obtain country-specific prevalence estimates and to compare disease odds ratios in different risk groups taking into account the sensitivities of the diagnostic methods applied. A total of 354 studies from 78 countries were included for the prevalence calculations, 194 (62.4%) were community-based studies, 121 (34.2%) were hospital-based studies and 39 (11.0%) were studies on refugees and immigrants. World maps with country data are provided. In numerous African, Asian and South-American resource-poor countries, information on S. stercoralis is lacking. The meta-analysis showed an association between HIV-infection/alcoholism and S. stercoralis infection (OR: 2.17 BCI: 1.18–4.01; OR: 6.69; BCI: 1.47–33.8), respectively. Conclusions Our findings show high infection prevalence rates in the general population in selected countries and geographical regions. S. stercoralis infection is prominent in several risk groups. Adequate information on the prevalence is still lacking from many countries. However, current information underscore that S. stercoralis must not be neglected. Further assessments in socio-economic and ecological settings are needed and integration into global helminth control is warranted. PMID:23875033

  17. Global capacity announcement of electrical distribution systems: A pragmatic approach

    OpenAIRE

    Cornélusse, Bertrand; Vangulick, David; Glavic, Mevludin; Ernst, Damien

    2015-01-01

    We propose a pragmatic procedure to facilitate the connection process of Distributed Generation (DG) with reference to the European regulatory framework where Distribution System Operators (DSOs) are, except in specific cases, not allowed to own their generation. The procedure is termed Global Capacity ANnouncement (GCAN) and is intended to compute the estimates of maximum generation connection amount at appropriate substations in a distribution system, to help generation connection decisions...

  18. The Sorcerer II Global Ocean Sampling Expedition: Expanding theUniverse of Protein Families

    Energy Technology Data Exchange (ETDEWEB)

    Yooseph, Shibu; Sutton, Granger; Rusch, Douglas B.; Halpern,Aaron L.; Williamson, Shannon J.; Remington, Karin; Eisen, Jonathan A.; Heidelberg, Karla B.; Manning, Gerard; Li, Weizhong; Jaroszewski, Lukasz; Cieplak, Piotr; Miller, Christopher S.; Li, Huiying; Mashiyama, Susan T.; Joachimiak, Marcin P.; van Belle, Christopher; Chandonia, John-Marc; Soergel, David A.; Zhai, Yufeng; Natarajan, Kannan; Lee, Shaun; Raphael,Benjamin J.; Bafna, Vineet; Friedman, Robert; Brenner, Steven E.; Godzik,Adam; Eisenberg, David; Dixon, Jack E.; Taylor, Susan S.; Strausberg,Robert L.; Frazier, Marvin; Venter, J.Craig

    2006-03-23

    Metagenomics projects based on shotgun sequencing of populations of micro-organisms yield insight into protein families. We used sequence similarity clustering to explore proteins with a comprehensive dataset consisting of sequences from available databases together with 6.12 million proteins predicted from an assembly of 7.7 million Global Ocean Sampling (GOS) sequences. The GOS dataset covers nearly all known prokaryotic protein families. A total of 3,995 medium- and large-sized clusters consisting of only GOS sequences are identified, out of which 1,700 have no detectable homology to known families. The GOS-only clusters contain a higher than expected proportion of sequences of viral origin, thus reflecting a poor sampling of viral diversity until now. Protein domain distributions in the GOS dataset and current protein databases show distinct biases. Several protein domains that were previously categorized as kingdom specific are shown to have GOS examples in other kingdoms. About 6,000 sequences (ORFans) from the literature that heretofore lacked similarity to known proteins have matches in the GOS data. The GOS dataset is also used to improve remote homology detection. Overall, besides nearly doubling the number of current proteins, the predicted GOS proteins also add a great deal of diversity to known protein families and shed light on their evolution. These observations are illustrated using several protein families, including phosphatases, proteases, ultraviolet-irradiation DNA damage repair enzymes, glutamine synthetase, and RuBisCO. The diversity added by GOS data has implications for choosing targets for experimental structure characterization as part of structural genomics efforts. Our analysis indicates that new families are being discovered at a rate that is linear or almost linear with the addition of new sequences, implying that we are still far from discovering all protein families in nature.

  19. The Sorcerer II Global Ocean Sampling expedition: expanding the universe of protein families.

    Directory of Open Access Journals (Sweden)

    Shibu Yooseph

    2007-03-01

    Full Text Available Metagenomics projects based on shotgun sequencing of populations of micro-organisms yield insight into protein families. We used sequence similarity clustering to explore proteins with a comprehensive dataset consisting of sequences from available databases together with 6.12 million proteins predicted from an assembly of 7.7 million Global Ocean Sampling (GOS sequences. The GOS dataset covers nearly all known prokaryotic protein families. A total of 3,995 medium- and large-sized clusters consisting of only GOS sequences are identified, out of which 1,700 have no detectable homology to known families. The GOS-only clusters contain a higher than expected proportion of sequences of viral origin, thus reflecting a poor sampling of viral diversity until now. Protein domain distributions in the GOS dataset and current protein databases show distinct biases. Several protein domains that were previously categorized as kingdom specific are shown to have GOS examples in other kingdoms. About 6,000 sequences (ORFans from the literature that heretofore lacked similarity to known proteins have matches in the GOS data. The GOS dataset is also used to improve remote homology detection. Overall, besides nearly doubling the number of current proteins, the predicted GOS proteins also add a great deal of diversity to known protein families and shed light on their evolution. These observations are illustrated using several protein families, including phosphatases, proteases, ultraviolet-irradiation DNA damage repair enzymes, glutamine synthetase, and RuBisCO. The diversity added by GOS data has implications for choosing targets for experimental structure characterization as part of structural genomics efforts. Our analysis indicates that new families are being discovered at a rate that is linear or almost linear with the addition of new sequences, implying that we are still far from discovering all protein families in nature.

  20. Distribution of Global Measures of Deviation Between the Empirical Distribution Function and Its Concave Majorant

    NARCIS (Netherlands)

    Kulikov, V.N.; Lopuhaä, H.P.

    2007-01-01

    We investigate the distribution of some global measures of deviation between the empirical distribution function and its least concave majorant. In the case that the underlying distribution has a strictly decreasing density, we prove asymptotic normality for several L k -type distances. In the case

  1. Architecture-Centric Development in Globally Distributed Projects

    Science.gov (United States)

    Sauer, Joachim

    In this chapter architecture-centric development is proposed as a means to strengthen the cohesion of distributed teams and to tackle challenges due to geographical and temporal distances and the clash of different cultures. A shared software architecture serves as blueprint for all activities in the development process and ties them together. Architecture-centric development thus provides a plan for task allocation, facilitates the cooperation of globally distributed developers, and enables continuous integration reaching across distributed teams. Advice is also provided for software architects who work with distributed teams in an agile manner.

  2. Evaluating Economic Impacts of Expanded Global Wood Energy Consumption with the USFPM/GFPM Model

    Science.gov (United States)

    Peter J. Ince; Andrew Kramp; Kenneth E. Skog

    2012-01-01

    A U.S. forest sector market module was developed within the general Global Forest Products Model. The U.S. module tracks regional timber markets, timber harvests by species group, and timber product outputs in greater detail than does the global model. This hybrid approach provides detailed regional market analysis for the United States although retaining the...

  3. Scrum master in a global distributed development team

    OpenAIRE

    Juhlin, Annica

    2009-01-01

    Companies around the world work more globally than ever and it reflects in the system development projects that run. The companies work span continents and the employees work together over the borders. This way of working, the global distributed, brings a number of opportunities for the company but also presents a lot of problems. The distributed way of working means that the teams and/or individuals are divided. I wanted to connect this way of working with the agile framework Scrum, partly d...

  4. Deviation from power law of the global seismic moment distribution

    Science.gov (United States)

    Serra, Isabel; Corral, Álvaro

    2017-01-01

    The distribution of seismic moment is of capital interest to evaluate earthquake hazard, in particular regarding the most extreme events. We make use of likelihood-ratio tests to compare the simple Gutenberg-Richter power-law (PL) distribution with two statistical models that incorporate an exponential tail, the so-called tapered Gutenberg-Richter (Tap) and the truncated gamma, when fitted to the global CMT earthquake catalog. Although the Tap distribution does not introduce any significant improvement of fit respect the PL, the truncated gamma does. Simulated samples of this distribution, with parameters β = 0.68 and mc = 9.15 and reshuffled in order to mimic the time occurrence of the order statistics of the empirical data, are able to explain the temporal heterogeneity of global seismicity both before and after the great Sumatra-Andaman earthquake of 2004.

  5. A Neurodynamic Approach to Distributed Optimization With Globally Coupled Constraints.

    Science.gov (United States)

    Le, Xinyi; Chen, Sijie; Yan, Zheng; Xi, Juntong

    2017-10-18

    In this paper, a distributed neurodynamic approach is proposed for constrained convex optimization. The objective function is a sum of local convex subproblems, whereas the constraints of these subproblems are coupled. Each local objective function is minimized individually with the proposed neurodynamic optimization approach. Through information exchange between connected neighbors only, all nodes can reach consensus on the Lagrange multipliers of all global equality and inequality constraints, and the decision variables converge to the global optimum in a distributed manner. Simulation results of two power system cases are discussed to substantiate the effectiveness and characteristics of the proposed approach.In this paper, a distributed neurodynamic approach is proposed for constrained convex optimization. The objective function is a sum of local convex subproblems, whereas the constraints of these subproblems are coupled. Each local objective function is minimized individually with the proposed neurodynamic optimization approach. Through information exchange between connected neighbors only, all nodes can reach consensus on the Lagrange multipliers of all global equality and inequality constraints, and the decision variables converge to the global optimum in a distributed manner. Simulation results of two power system cases are discussed to substantiate the effectiveness and characteristics of the proposed approach.

  6. Global distribution of pauses observed with satellite measurements

    Indian Academy of Sciences (India)

    Several studies have been carried out on the tropopause, stratopause, and mesopause (collectively termed as 'pauses') independently; however, all the pauses have not been studied together. We present global distribution of altitudes and temperatures of these pauses observed with long-term space borne high resolution ...

  7. Equilibrium of global amphibian species distributions with climate

    DEFF Research Database (Denmark)

    Munguí­a, Mariana; Rahbek, Carsten; Rangel, Thiago F.

    2012-01-01

    of their potential distributions than species in the Nearctic, Madagascar, and Australasia. We acknowledge that our models underestimate non equilibrium, and discuss potential reasons for the observed patterns. From a modeling perspective our results support the view that at global scale bioclimatic envelope models...

  8. Cloud manufacturing distributed computing technologies for global and sustainable manufacturing

    CERN Document Server

    Mehnen, Jörn

    2013-01-01

    Global networks, which are the primary pillars of the modern manufacturing industry and supply chains, can only cope with the new challenges, requirements and demands when supported by new computing and Internet-based technologies. Cloud Manufacturing: Distributed Computing Technologies for Global and Sustainable Manufacturing introduces a new paradigm for scalable service-oriented sustainable and globally distributed manufacturing systems.   The eleven chapters in this book provide an updated overview of the latest technological development and applications in relevant research areas.  Following an introduction to the essential features of Cloud Computing, chapters cover a range of methods and applications such as the factors that actually affect adoption of the Cloud Computing technology in manufacturing companies and new geometrical simplification method to stream 3-Dimensional design and manufacturing data via the Internet. This is further supported case studies and real life data for Waste Electrical ...

  9. Golden Relics & Historical Standards: How the OECD is Expanding Global Education Governance through PISA for Development

    Science.gov (United States)

    Addey, Camilla

    2017-01-01

    Setting this paper against the backdrop of scholarly research on recent changes in the OECD's approach and workings in education, I analyse how the OECD has reinforced its infrastructural and epistemological global governance through the Programme for International Student Assessment (PISA) for Development (PISA-D). Drawing on qualitative data,…

  10. Equilibrium of Global Amphibian Species Distributions with Climate

    Science.gov (United States)

    Munguía, Mariana; Rahbek, Carsten; Rangel, Thiago F.; Diniz-Filho, Jose Alexandre F.; Araújo, Miguel B.

    2012-01-01

    A common assumption in bioclimatic envelope modeling is that species distributions are in equilibrium with contemporary climate. A number of studies have measured departures from equilibrium in species distributions in particular regions, but such investigations were never carried out for a complete lineage across its entire distribution. We measure departures of equilibrium with contemporary climate for the distributions of the world amphibian species. Specifically, we fitted bioclimatic envelopes for 5544 species using three presence-only models. We then measured the proportion of the modeled envelope that is currently occupied by the species, as a metric of equilibrium of species distributions with climate. The assumption was that the greater the difference between modeled bioclimatic envelope and the occupied distribution, the greater the likelihood that species distribution would not be at equilibrium with contemporary climate. On average, amphibians occupied 30% to 57% of their potential distributions. Although patterns differed across regions, there were no significant differences among lineages. Species in the Neotropic, Afrotropics, Indo-Malay, and Palaearctic occupied a smaller proportion of their potential distributions than species in the Nearctic, Madagascar, and Australasia. We acknowledge that our models underestimate non equilibrium, and discuss potential reasons for the observed patterns. From a modeling perspective our results support the view that at global scale bioclimatic envelope models might perform similarly across lineages but differently across regions. PMID:22511938

  11. Mapping local and global variability in plant trait distributions

    Energy Technology Data Exchange (ETDEWEB)

    Butler, Ethan E.; Datta, Abhirup; Flores-Moreno, Habacuc; Chen, Ming; Wythers, Kirk R.; Fazayeli, Farideh; Banerjee, Arindam; Atkin, Owen K.; Kattge, Jens; Amiaud, Bernard; Blonder, Benjamin; Boenisch, Gerhard; Bond-Lamberty, Ben; Brown, Kerry A.; Byun, Chaeho; Campetella, Giandiego; Cerabolini, Bruno E. L.; Cornelissen, Johannes H. C.; Craine, Joseph M.; Craven, Dylan; de Vries, Franciska T.; Díaz, Sandra; Domingues, Tomas F.; Forey, Estelle; González-Melo, Andrés; Gross, Nicolas; Han, Wenxuan; Hattingh, Wesley N.; Hickler, Thomas; Jansen, Steven; Kramer, Koen; Kraft, Nathan J. B.; Kurokawa, Hiroko; Laughlin, Daniel C.; Meir, Patrick; Minden, Vanessa; Niinemets, Ülo; Onoda, Yusuke; Peñuelas, Josep; Read, Quentin; Sack, Lawren; Schamp, Brandon; Soudzilovskaia, Nadejda A.; Spasojevic, Marko J.; Sosinski, Enio; Thornton, Peter E.; Valladares, Fernando; van Bodegom, Peter M.; Williams, Mathew; Wirth, Christian; Reich, Peter B.

    2017-12-01

    Accurate trait-environment relationships and global maps of plant trait distributions represent a needed stepping stone in global biogeography and are critical constraints of key parameters for land models. Here, we use a global data set of plant traits to map trait distributions closely coupled to photosynthesis and foliar respiration: specific leaf area (SLA), and dry mass-based concentrations of leaf nitrogen (Nm) and phosphorus (Pm); We propose two models to extrapolate geographically sparse point data to continuous spatial surfaces. The first is a categorical model using species mean trait values, categorized into plant functional types (PFTs) and extrapolating to PFT occurrence ranges identified by remote sensing. The second is a Bayesian spatial model that incorporates information about PFT, location and environmental covariates to estimate trait distributions. Both models are further stratified by varying the number of PFTs; The performance of the models was evaluated based on their explanatory and predictive ability. The Bayesian spatial model leveraging the largest number of PFTs produced the best maps; The interpolation of full trait distributions enables a wider diversity of vegetation to be represented across the land surface. These maps may be used as input to Earth System Models and to evaluate other estimates of functional diversity.

  12. Distributed Global Function Model Finding for Wireless Sensor Network Data

    Directory of Open Access Journals (Sweden)

    Song Deng

    2016-01-01

    Full Text Available Function model finding has become an important tool for analysis of data collected from wireless sensor networks (WSNs. With the development of WSNs, a large number of sensors have been widely deployed so that the collected data show the characteristics of distribution and mass. For distributed and massive sensor data, traditional centralized function model finding algorithms would lead to a significant decrease in performance. To solve this problem, this paper proposes a distributed global function model finding algorithm for wireless sensor network data (DGFMF-WSND. In DGFMF-WSND, on the basis of gene expression programming (GEP, an adaptive population generation strategy based on sub-population associated evolution is applied to improve the convergence speed of GEP. Secondly, to solve the generation of global function model in distributed wireless sensor networks data, this paper provides a global model generation algorithm based on unconstrained nonlinear least squares. Four representative datasets are used to evaluate the performance of the proposed algorithm. The comparative results show that the improved GEP with adaptive population generation strategy outperforms all other algorithms on the average convergence speed, time-consumption, value of R-square, and prediction accuracy. Meanwhile, experimental results also show that DGFMF-WSND has a clear advantage in terms of time-consumption and error of fitting. Moreover, with increasing of dataset size, DGFMF-WSND also demonstrates good speed-up ratio and scale-up ratio.

  13. The global distribution of deep-water Antipatharia habitat

    Science.gov (United States)

    Yesson, Chris; Bedford, Faye; Rogers, Alex D.; Taylor, Michelle L.

    2017-11-01

    Antipatharia are a diverse group of corals with many species found in deep water. Many Antipatharia are habitat for associates, have extreme longevity and some species can occur beyond 8500 m depth. As they are major constituents of'coral gardens', which are Vulnerable Marine Ecosystems (VMEs), knowledge of their distribution and environmental requirements is an important pre-requisite for informed conservation planning particularly where the expense and difficulty of deep-sea sampling prohibits comprehensive surveys. This study uses a global database of Antipatharia distribution data to perform habitat suitability modelling using the Maxent methodology to estimate the global extent of black coral habitat suitability. The model of habitat suitability is driven by temperature but there is notable influence from other variables of topography, surface productivity and oxygen levels. This model can be used to predict areas of suitable habitat, which can be useful for conservation planning. The global distribution of Antipatharia habitat suitability shows a marked contrast with the distribution of specimen observations, indicating that many potentially suitable areas have not been sampled, and that sampling effort has been disproportionate to shallow, accessible areas inside marine protected areas (MPAs). Although 25% of Antipatharia observations are located in MPAs, only 7-8% of predicted suitable habitat is protected, which is short of the Convention on Biological Diversity target to protect 10% of ocean habitats by 2020.

  14. Expanding the global network of protected areas to save the imperiled mediterranean biome.

    Science.gov (United States)

    Underwood, Emma C; Klausmeyer, Kirk R; Cox, Robin L; Busby, Sylvia M; Morrison, Scott A; Shaw, M Rebecca

    2009-02-01

    : Global goals established by the Convention on Biological Diversity stipulate that 10% of the world's ecological regions must be effectively conserved by 2010. To meet that goal for the mediterranean biome, at least 5% more land must be formally protected over the next few years. Although global assessments identify the mediterranean biome as a priority, without biologically meaningful analysis units, finer-resolution data, and corresponding prioritization analysis, future conservation investments could lead to more area being protected without increasing the representation of unique mediterranean ecosystems. We used standardized analysis units and six potential natural vegetation types stratified by 3 elevation zones in a global gap analysis that systematically explored conservation priorities across the mediterranean biome. The highest levels of protection were in Australia, South Africa, and California-Baja California (from 9-11%), and the lowest levels of protection were in Chile and the mediterranean Basin (biome only one of the six vegetation types--mediterranean shrubland--exceeded 10% protection. The remaining vegetation types--grassland, scrub, succulent dominated, woodland, and forest--each had biome, we identified biodiversity assemblages with 30% conversion and suggest that these assemblages be elevated to high-priority status in future conservation efforts.

  15. Global distribution of measles genotypes and measles molecular epidemiology.

    Science.gov (United States)

    Rota, Paul A; Brown, Kevin; Mankertz, Annette; Santibanez, Sabine; Shulga, Sergey; Muller, Claude P; Hübschen, Judith M; Siqueira, Marilda; Beirnes, Jennifer; Ahmed, Hinda; Triki, Henda; Al-Busaidy, Suleiman; Dosseh, Annick; Byabamazima, Charles; Smit, Sheilagh; Akoua-Koffi, Chantal; Bwogi, Josephine; Bukenya, Henry; Wairagkar, Niteen; Ramamurty, Nalini; Incomserb, Patcha; Pattamadilok, Sirima; Jee, Youngmee; Lim, Wilina; Xu, Wenbo; Komase, Katsuhiro; Takeda, Makoto; Tran, Thomas; Castillo-Solorzano, Carlos; Chenoweth, Paul; Brown, David; Mulders, Mick N; Bellini, William J; Featherstone, David

    2011-07-01

    A critical component of laboratory surveillance for measles is the genetic characterization of circulating wild-type viruses. The World Health Organization (WHO) Measles and Rubella Laboratory Network (LabNet), provides for standardized testing in 183 countries and supports genetic characterization of currently circulating strains of measles viruses. The goal of this report is to describe the lessons learned from nearly 20 years of virologic surveillance for measles, to describe the global databases for measles sequences, and to provide regional updates about measles genotypes detected by recent surveillance activities. Virologic surveillance for measles is now well established in all of the WHO regions, and most countries have conducted at least some baseline surveillance. The WHO Global Genotype Database contains >7000 genotype reports, and the Measles Nucleotide Surveillance (MeaNS) contains >4000 entries. This sequence information has proven to be extremely useful for tracking global transmission patterns and for documenting the interruption of transmission in some countries. The future challenges will be to develop quality control programs for molecular methods and to continue to expand virologic surveillance activities in all regions. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2011.

  16. Effects of Individual Success on Globally Distributed Team Performance

    OpenAIRE

    Yılmaz, Onur

    2013-01-01

    Necessity of different competencies with high level of knowledge makes it inevitable that software development is a team work. With the today's technology, teams can communicate both synchronously and asynchronously using different online collaboration tools throughout the world. Researches indicate that there are many factors that affect the team success and in this paper, effect of individual success on globally distributed team performance will be analyzed. Student team projects undertaken...

  17. Global distribution and drivers of language extinction risk

    DEFF Research Database (Denmark)

    Amano, Tatsuya; Sandel, Brody Steven; Eager, Heidi

    2014-01-01

    Many of the world's languages face serious risk of extinction. Efforts to prevent this cultural loss are severely constrained by a poor understanding of the geographical patterns and drivers of extinction risk. We quantify the global distribution of language extinction risk-represented by small....... However, risks of future language losses are especially high in the tropics and in the Himalayas, as these regions harbour many small-population languages and are undergoing rapid economic growth....

  18. Global pyrogeography: the current and future distribution of wildfire.

    Directory of Open Access Journals (Sweden)

    Meg A Krawchuk

    Full Text Available Climate change is expected to alter the geographic distribution of wildfire, a complex abiotic process that responds to a variety of spatial and environmental gradients. How future climate change may alter global wildfire activity, however, is still largely unknown. As a first step to quantifying potential change in global wildfire, we present a multivariate quantification of environmental drivers for the observed, current distribution of vegetation fires using statistical models of the relationship between fire activity and resources to burn, climate conditions, human influence, and lightning flash rates at a coarse spatiotemporal resolution (100 km, over one decade. We then demonstrate how these statistical models can be used to project future changes in global fire patterns, highlighting regional hotspots of change in fire probabilities under future climate conditions as simulated by a global climate model. Based on current conditions, our results illustrate how the availability of resources to burn and climate conditions conducive to combustion jointly determine why some parts of the world are fire-prone and others are fire-free. In contrast to any expectation that global warming should necessarily result in more fire, we find that regional increases in fire probabilities may be counter-balanced by decreases at other locations, due to the interplay of temperature and precipitation variables. Despite this net balance, our models predict substantial invasion and retreat of fire across large portions of the globe. These changes could have important effects on terrestrial ecosystems since alteration in fire activity may occur quite rapidly, generating ever more complex environmental challenges for species dispersing and adjusting to new climate conditions. Our findings highlight the potential for widespread impacts of climate change on wildfire, suggesting severely altered fire regimes and the need for more explicit inclusion of fire in research

  19. Global patterns of city size distributions and their fundamental drivers.

    Directory of Open Access Journals (Sweden)

    Ethan H Decker

    Full Text Available Urban areas and their voracious appetites are increasingly dominating the flows of energy and materials around the globe. Understanding the size distribution and dynamics of urban areas is vital if we are to manage their growth and mitigate their negative impacts on global ecosystems. For over 50 years, city size distributions have been assumed to universally follow a power function, and many theories have been put forth to explain what has become known as Zipf's law (the instance where the exponent of the power function equals unity. Most previous studies, however, only include the largest cities that comprise the tail of the distribution. Here we show that national, regional and continental city size distributions, whether based on census data or inferred from cluster areas of remotely-sensed nighttime lights, are in fact lognormally distributed through the majority of cities and only approach power functions for the largest cities in the distribution tails. To explore generating processes, we use a simple model incorporating only two basic human dynamics, migration and reproduction, that nonetheless generates distributions very similar to those found empirically. Our results suggest that macroscopic patterns of human settlements may be far more constrained by fundamental ecological principles than more fine-scale socioeconomic factors.

  20. Expanding the Metchnikoff postulate: oral health is crucial in a successful global aging management strategy.

    Science.gov (United States)

    Illuzzi, Nicola; Galli, Romina; Kushugulova, Almagul; Zhumadilov, Zhaxybay; Licciardello, Orazio; Marotta, Francesco

    2014-04-01

    The mouth offers a unique opportunity for the physician and dental hygienist to evaluate and monitor a number of early nutritional-related diseases and vitamin deficiencies in still-healthy people. Increasing evidence suggests that periodontal disease might be associated with several systemic diseases (diabetes, immunosuppression, obesity, hormonal changes). Conversely, oral/periodontal disease might be the perpetuating factor or possibly the trigger of chronic illnesses via the activation of pro-inflammatory cytokines from monocytes and polymorphonuclear leukocytes in the sub-gingival biofilm and oral microbiome unbalance. Office-based microbiological and susceptibility genomic testing in the oral cavity (e.g., BACTOdent-DENTYgen, 4P-Genomics, Luxembourg) are expected to be widespread tools in a global approach for an age-management strategy connecting oral health and personalized solutions.

  1. The Global Distribution and Drivers of Alien Bird Species Richness

    Science.gov (United States)

    Dyer, Ellie E.; Cassey, Phillip; Redding, David W.; Collen, Ben; Franks, Victoria; Gaston, Kevin J.; Jones, Kate E.; Kark, Salit; Orme, C. David L.; Blackburn, Tim M.

    2017-01-01

    Alien species are a major component of human-induced environmental change. Variation in the numbers of alien species found in different areas is likely to depend on a combination of anthropogenic and environmental factors, with anthropogenic factors affecting the number of species introduced to new locations, and when, and environmental factors influencing how many species are able to persist there. However, global spatial and temporal variation in the drivers of alien introduction and species richness remain poorly understood. Here, we analyse an extensive new database of alien birds to explore what determines the global distribution of alien species richness for an entire taxonomic class. We demonstrate that the locations of origin and introduction of alien birds, and their identities, were initially driven largely by European (mainly British) colonialism. However, recent introductions are a wider phenomenon, involving more species and countries, and driven in part by increasing economic activity. We find that, globally, alien bird species richness is currently highest at midlatitudes and is strongly determined by anthropogenic effects, most notably the number of species introduced (i.e., “colonisation pressure”). Nevertheless, environmental drivers are also important, with native and alien species richness being strongly and consistently positively associated. Our results demonstrate that colonisation pressure is key to understanding alien species richness, show that areas of high native species richness are not resistant to colonisation by alien species at the global scale, and emphasise the likely ongoing threats to global environments from introductions of species. PMID:28081142

  2. The Global Distribution and Drivers of Alien Bird Species Richness.

    Science.gov (United States)

    Dyer, Ellie E; Cassey, Phillip; Redding, David W; Collen, Ben; Franks, Victoria; Gaston, Kevin J; Jones, Kate E; Kark, Salit; Orme, C David L; Blackburn, Tim M

    2017-01-01

    Alien species are a major component of human-induced environmental change. Variation in the numbers of alien species found in different areas is likely to depend on a combination of anthropogenic and environmental factors, with anthropogenic factors affecting the number of species introduced to new locations, and when, and environmental factors influencing how many species are able to persist there. However, global spatial and temporal variation in the drivers of alien introduction and species richness remain poorly understood. Here, we analyse an extensive new database of alien birds to explore what determines the global distribution of alien species richness for an entire taxonomic class. We demonstrate that the locations of origin and introduction of alien birds, and their identities, were initially driven largely by European (mainly British) colonialism. However, recent introductions are a wider phenomenon, involving more species and countries, and driven in part by increasing economic activity. We find that, globally, alien bird species richness is currently highest at midlatitudes and is strongly determined by anthropogenic effects, most notably the number of species introduced (i.e., "colonisation pressure"). Nevertheless, environmental drivers are also important, with native and alien species richness being strongly and consistently positively associated. Our results demonstrate that colonisation pressure is key to understanding alien species richness, show that areas of high native species richness are not resistant to colonisation by alien species at the global scale, and emphasise the likely ongoing threats to global environments from introductions of species.

  3. Global distribution and conservation of rare and threatened vertebrates.

    Science.gov (United States)

    Grenyer, Richard; Orme, C David L; Jackson, Sarah F; Thomas, Gavin H; Davies, Richard G; Davies, T Jonathan; Jones, Kate E; Olson, Valerie A; Ridgely, Robert S; Rasmussen, Pamela C; Ding, Tzung-Su; Bennett, Peter M; Blackburn, Tim M; Gaston, Kevin J; Gittleman, John L; Owens, Ian P F

    2006-11-02

    Global conservation strategies commonly assume that different taxonomic groups show congruent geographical patterns of diversity, and that the distribution of extinction-prone species in one group can therefore act as a surrogate for vulnerable species in other groups when conservation decisions are being made. The validity of these assumptions remains unclear, however, because previous tests have been limited in both geographical and taxonomic extent. Here we use a database on the global distribution of 19,349 living bird, mammal and amphibian species to show that, although the distribution of overall species richness is very similar among these groups, congruence in the distribution of rare and threatened species is markedly lower. Congruence is especially low among the very rarest species. Cross-taxon congruence is also highly scale dependent, being particularly low at the finer spatial resolutions relevant to real protected areas. 'Hotspots' of rarity and threat are therefore largely non-overlapping across groups, as are areas chosen to maximize species complementarity. Overall, our results indicate that 'silver-bullet' conservation strategies alone will not deliver efficient conservation solutions. Instead, priority areas for biodiversity conservation must be based on high-resolution data from multiple taxa.

  4. Global Distribution of Campylobacter jejuni Penner Serotypes: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Brian L Pike

    Full Text Available Penner serotyping has been the principal method for differentiating Campylobacter isolates since its inception. Campylobacter capsule polysaccharide (CPS, the principal serodeterminant on which Penner serotyping is based, is presently of interest as a vaccine component. To determine the required valency of an effective CPS-based vaccine, a comprehensive understanding of CPS distribution is needed. Because of the association between Penner serotype and CPS, we conducted a systematic review to estimate the frequency and distribution of Penner serotypes associated with cases of Campylobacteriosis. In total, more than 21,000 sporadic cases of C. jejuni cases were identified for inclusion. While regional variation exists, distribution estimates indicate that eight serotypes accounted for more than half of all sporadic diarrheal cases globally and three serotypes (HS4 complex, HS2, and HS1/44 were dominant inter-regionally as well as globally. Furthermore, a total of 17 different serotypes reached a representation of 2% or greater in at least one of the five regions sampled. While this review is an important first step in defining CPS distribution, these results make it clear that significant gaps remain in our knowledge. Eliminating these gaps will be critical to future vaccine development efforts.

  5. Impact of climate change on global malaria distribution.

    Science.gov (United States)

    Caminade, Cyril; Kovats, Sari; Rocklov, Joacim; Tompkins, Adrian M; Morse, Andrew P; Colón-González, Felipe J; Stenlund, Hans; Martens, Pim; Lloyd, Simon J

    2014-03-04

    Malaria is an important disease that has a global distribution and significant health burden. The spatial limits of its distribution and seasonal activity are sensitive to climate factors, as well as the local capacity to control the disease. Malaria is also one of the few health outcomes that has been modeled by more than one research group and can therefore facilitate the first model intercomparison for health impacts under a future with climate change. We used bias-corrected temperature and rainfall simulations from the Coupled Model Intercomparison Project Phase 5 climate models to compare the metrics of five statistical and dynamical malaria impact models for three future time periods (2030s, 2050s, and 2080s). We evaluated three malaria outcome metrics at global and regional levels: climate suitability, additional population at risk and additional person-months at risk across the model outputs. The malaria projections were based on five different global climate models, each run under four emission scenarios (Representative Concentration Pathways, RCPs) and a single population projection. We also investigated the modeling uncertainty associated with future projections of populations at risk for malaria owing to climate change. Our findings show an overall global net increase in climate suitability and a net increase in the population at risk, but with large uncertainties. The model outputs indicate a net increase in the annual person-months at risk when comparing from RCP2.6 to RCP8.5 from the 2050s to the 2080s. The malaria outcome metrics were highly sensitive to the choice of malaria impact model, especially over the epidemic fringes of the malaria distribution.

  6. Measurement of the Vertical Distribution of Aerosol by Globally Distributed MP Lidar Network Sites

    Science.gov (United States)

    Spinhirne, James; Welton, Judd; Campbell, James; Starr, David OC. (Technical Monitor)

    2001-01-01

    The global distribution of aerosol has an important influence on climate through the scattering and absorption of shortwave radiation and through modification of cloud optical properties. Current satellite and other data already provide a great amount of information on aerosol distribution. However there are critical parameters that can only be obtained by active optical profiling. For aerosol, no passive technique can adequately resolve the height profile of aerosol. The aerosol height distribution is required for any model for aerosol transport and the height resolved radiative heating/cooling effect of aerosol. The Geoscience Laser Altimeter System (GLAS) is an orbital lidar to be launched by 2002. GLAS will provide global measurements of the height distribution of aerosol. The sampling will be limited by nadir only coverage. There is a need for local sites to address sampling, and accuracy factors. Full time measurements of the vertical distribution of aerosol are now being acquired at a number of globally distributed MP (micro pulse) lidar sites. The MP lidar systems provide profiling of all significant cloud and aerosol to the limit of signal attenuation from compact, eye safe instruments. There are currently six sites in operation and over a dozen planned. At all sites there are a complement of passive aerosol and radiation measurements supporting the lidar data. Four of the installations are at Atmospheric Radiation Measurement program sites. The aerosol measurements, retrievals and data products from the network sites will be discussed. The current and planned application of data to supplement satellite aerosol measurements is covered.

  7. Global spatiotemporal distribution of soil respiration modeled using a global database

    Science.gov (United States)

    Hashimoto, S.; Carvalhais, N.; Ito, A.; Migliavacca, M.; Nishina, K.; Reichstein, M.

    2015-07-01

    The flux of carbon dioxide from the soil to the atmosphere (soil respiration) is one of the major fluxes in the global carbon cycle. At present, the accumulated field observation data cover a wide range of geographical locations and climate conditions. However, there are still large uncertainties in the magnitude and spatiotemporal variation of global soil respiration. Using a global soil respiration data set, we developed a climate-driven model of soil respiration by modifying and updating Raich's model, and the global spatiotemporal distribution of soil respiration was examined using this model. The model was applied at a spatial resolution of 0.5°and a monthly time step. Soil respiration was divided into the heterotrophic and autotrophic components of respiration using an empirical model. The estimated mean annual global soil respiration was 91 Pg C yr-1 (between 1965 and 2012; Monte Carlo 95 % confidence interval: 87-95 Pg C yr-1) and increased at the rate of 0.09 Pg C yr-2. The contribution of soil respiration from boreal regions to the total increase in global soil respiration was on the same order of magnitude as that of tropical and temperate regions, despite a lower absolute magnitude of soil respiration in boreal regions. The estimated annual global heterotrophic respiration and global autotrophic respiration were 51 and 40 Pg C yr-1, respectively. The global soil respiration responded to the increase in air temperature at the rate of 3.3 Pg C yr-1 °C-1, and Q10 = 1.4. Our study scaled up observed soil respiration values from field measurements to estimate global soil respiration and provide a data-oriented estimate of global soil respiration. The estimates are based on a semi-empirical model parameterized with over one thousand data points. Our analysis indicates that the climate controls on soil respiration may translate into an increasing trend in global soil respiration and our analysis emphasizes the relevance of the soil carbon flux from soil to

  8. Amdoparvoviruses in small mammals: expanding our understanding of parvovirus diversity, distribution, and pathology

    Directory of Open Access Journals (Sweden)

    Marta eCanuti

    2015-10-01

    Full Text Available Many new viruses have been discovered recently, thanks in part to the advent of next-generation sequencing technologies. Among the Parvoviridae, three novel members of the genus Amdoparvovirus have been described in the last four years, expanding this genus that had contained a single species since its discovery, Aleutian mink disease virus. The increasing number of molecular and epidemiological studies on these viruses around the world also highlights the growing interest in this genus. Some aspects of amdoparvoviruses have been well characterized, however many other aspects still need to be elucidated and the most recent reviews on this topic are outdated. We provide here an up-to-date overview of what is known and what still needs to be investigated about these scientifically and clinically relevant animal viruses.

  9. Path to 'Stardom' in Globally Distributed Hybrid Teams

    DEFF Research Database (Denmark)

    Sarker, Suprateek; Hove-Kirkeby, Sarah; Sarker, Saonee

    2011-01-01

    Although distributed teams have been researched extensively in information systems and decision science disciplines, a review of the literature suggests that the dominant focus has been on understanding the factors affecting performance at the team level. There has however been an increasing...... recognition that specific individuals within such teams are often critical to the team's performance. Consequently, existing knowledge about such teams may be enhanced by examining the factors that affect the performance of individual team members. This study attempts to address this need by identifying...... individuals who emerge as “stars” in globally distributed teams involved in knowledge work such as information systems development (ISD). Specifically, the study takes a knowledge-centered view in explaining which factors lead to “stardom” in such teams. Further, it adopts a social network approach consistent...

  10. 76 FR 21033 - International Business Machines (IBM), Sales and Distribution Business Unit, Global Sales...

    Science.gov (United States)

    2011-04-14

    ... workers of International Business Machines (IBM), Sales and Distribution Business Unit, Global Sales... Employment and Training Administration International Business Machines (IBM), Sales and Distribution Business Unit, Global Sales Solution Department, Off-Site Teleworker in Centerport, New York; Notice of...

  11. Global Analysis for a Delay-Distributed SIR Epidemic Model

    Directory of Open Access Journals (Sweden)

    Kaddar Abdelilah

    2013-05-01

    Full Text Available One of the most tools for describing the incubation period in the epidemiological dynamic models is the distributed delays. In this paper, we propose a delay-distributed SIR epidemic model with a nonlinear incidence rate. Using the Lyapunov theory and LaSalle’s principle, we show the global asymptotic stability of the disease-free and the endemic equilibria. This analysis extends and performs existing results. En épidémiologie le retard joue un rôle très important dans la représentation de la période d’incubation. Dans ce travail, nous étudions un modèle SIR à retard distribué, avec une fonction d’incidence non linéaire. Pour analyser la stabilité globale du point d’équilibre sans maladie et du point d’équilibre endémique, nous utilisons la théorie de Lyapunov et le principe d’invariance de LaSalle.

  12. Global distribution of urban parameters derived from high-resolution global datasets for weather modelling

    Science.gov (United States)

    Kawano, N.; Varquez, A. C. G.; Dong, Y.; Kanda, M.

    2016-12-01

    Numerical model such as Weather Research and Forecasting model coupled with single-layer Urban Canopy Model (WRF-UCM) is one of the powerful tools to investigate urban heat island. Urban parameters such as average building height (Have), plain area index (λp) and frontal area index (λf), are necessary inputs for the model. In general, these parameters are uniformly assumed in WRF-UCM but this leads to unrealistic urban representation. Distributed urban parameters can also be incorporated into WRF-UCM to consider a detail urban effect. The problem is that distributed building information is not readily available for most megacities especially in developing countries. Furthermore, acquiring real building parameters often require huge amount of time and money. In this study, we investigated the potential of using globally available satellite-captured datasets for the estimation of the parameters, Have, λp, and λf. Global datasets comprised of high spatial resolution population dataset (LandScan by Oak Ridge National Laboratory), nighttime lights (NOAA), and vegetation fraction (NASA). True samples of Have, λp, and λf were acquired from actual building footprints from satellite images and 3D building database of Tokyo, New York, Paris, Melbourne, Istanbul, Jakarta and so on. Regression equations were then derived from the block-averaging of spatial pairs of real parameters and global datasets. Results show that two regression curves to estimate Have and λf from the combination of population and nightlight are necessary depending on the city's level of development. An index which can be used to decide which equation to use for a city is the Gross Domestic Product (GDP). On the other hand, λphas less dependence on GDP but indicated a negative relationship to vegetation fraction. Finally, a simplified but precise approximation of urban parameters through readily-available, high-resolution global datasets and our derived regressions can be utilized to estimate a

  13. Approaches to a global quantum key distribution network

    Science.gov (United States)

    Islam, Tanvirul; Bedington, Robert; Ling, Alexander

    2017-10-01

    Progress in realising quantum computers threatens to weaken existing public key encryption infrastructure. A global quantum key distribution (QKD) network can play a role in computational attack-resistant encryption. Such a network could use a constellation of high altitude platforms such as airships and satellites as trusted nodes to facilitate QKD between any two points on the globe on demand. This requires both space-to-ground and inter-platform links. However, the prohibitive cost of traditional satellite based development limits the experimental work demonstrating relevant technologies. To accelerate progress towards a global network, we use an emerging class of shoe-box sized spacecraft known as CubeSats. We have designed a polarization entangled photon pair source that can operate on board CubeSats. The robustness and miniature form factor of our entanglement source makes it especially suitable for performing pathfinder missions that studies QKD between two high altitude platforms. The technological outcomes of such mission would be the essential building blocks for a global QKD network.

  14. The global distribution and dynamics of surface soil moisture

    Science.gov (United States)

    McColl, Kaighin A.; Alemohammad, Seyed Hamed; Akbar, Ruzbeh; Konings, Alexandra G.; Yueh, Simon; Entekhabi, Dara

    2017-01-01

    Surface soil moisture has a direct impact on food security, human health and ecosystem function. It also plays a key role in the climate system, and the development and persistence of extreme weather events such as droughts, floods and heatwaves. However, sparse and uneven observations have made it difficult to quantify the global distribution and dynamics of surface soil moisture. Here we introduce a metric of soil moisture memory and use a full year of global observations from NASA's Soil Moisture Active Passive mission to show that surface soil moisture--a storage believed to make up less than 0.001% of the global freshwater budget by volume, and equivalent to an, on average, 8-mm thin layer of water covering all land surfaces--plays a significant role in the water cycle. Specifically, we find that surface soil moisture retains a median 14% of precipitation falling on land after three days. Furthermore, the retained fraction of the surface soil moisture storage after three days is highest over arid regions, and in regions where drainage to groundwater storage is lowest. We conclude that lower groundwater storage in these regions is due not only to lower precipitation, but also to the complex partitioning of the water cycle by the surface soil moisture storage layer at the land surface.

  15. Opportunities drive the global distribution of protected areas

    Directory of Open Access Journals (Sweden)

    Germán Baldi

    2017-02-01

    Full Text Available Background Protected areas, regarded today as a cornerstone of nature conservation, result from an array of multiple motivations and opportunities. We explored at global and regional levels the current distribution of protected areas along biophysical, human, and biological gradients, and assessed to what extent protection has pursued (i a balanced representation of biophysical environments, (ii a set of preferred conditions (biological, spiritual, economic, or geopolitical, or (iii existing opportunities for conservation regardless of any representation or preference criteria. Methods We used histograms to describe the distribution of terrestrial protected areas along biophysical, human, and biological independent gradients and linear and non-linear regression and correlation analyses to describe the sign, shape, and strength of the relationships. We used a random forest analysis to rank the importance of different variables related to conservation preferences and opportunity drivers, and an evenness metric to quantify representativeness. Results We find that protection at a global level is primarily driven by the opportunities provided by isolation and a low population density (variable importance = 34.6 and 19.9, respectively. Preferences play a secondary role, with a bias towards tourism attractiveness and proximity to international borders (variable importance = 12.7 and 3.4, respectively. Opportunities shape protection strongly in “North America & Australia–NZ” and “Latin America & Caribbean,” while the importance of the representativeness of biophysical environments is higher in “Sub-Saharan Africa” (1.3 times the average of other regions. Discussion Environmental representativeness and biodiversity protection are top priorities in land conservation agendas. However, our results suggest that they have been minor players driving current protection at both global and regional levels. Attempts to increase their relevance will

  16. Update on the global distribution of genotypes of wild type measles viruses.

    Science.gov (United States)

    Rota, Paul A; Bellini, William J

    2003-05-15

    Molecular characterization of measles viruses is an important component of measles surveillance because these studies enhance our ability to identify the source and transmission pathways of the virus. Molecular surveillance is most beneficial when it is possible to observe the change in virus genotypes over time in a particular region. Such information can help to document the interruption of transmission of measles virus and thus provide an important method for assessing the effectiveness of vaccination programs. It is recommended that virus surveillance be conducted during all phases of measles control and be expanded to give an accurate description of the global distribution of measles genotypes. This review provides updated information on the circulation patterns of measles genotypes and examples of the utility of virologic surveillance.

  17. 76 FR 32231 - International Business Machines (IBM), Sales and Distribution Business Unit, Global Sales...

    Science.gov (United States)

    2011-06-03

    ... Business Machines (IBM), Sales and Distribution Business Unit, Global Sales Solution Department, off-site... and location is International Business Machines (IBM), Sales and Distribution Business Unit, Global... totally or partially separated from IBM, Sales and Distribution Business Unit, Global Sales Solution...

  18. The global distribution of ammonia emissions from seabird colonies

    Science.gov (United States)

    Riddick, S. N.; Dragosits, U.; Blackall, T. D.; Daunt, F.; Wanless, S.; Sutton, M. A.

    2012-08-01

    Seabird colonies represent a significant source of atmospheric ammonia (NH3) in remote maritime systems, producing a source of nitrogen that may encourage plant growth, alter terrestrial plant community composition and affect the surrounding marine ecosystem. To investigate seabird NH3 emissions on a global scale, we developed a contemporary seabird database including a total seabird population of 261 million breeding pairs. We used this in conjunction with a bioenergetics model to estimate the mass of nitrogen excreted by all seabirds at each breeding colony. The results combined with the findings of mid-latitude field studies of volatilization rates estimate the global distribution of NH3 emissions from seabird colonies on an annual basis. The largest uncertainty in our emission estimate concerns the potential temperature dependence of NH3 emission. To investigate this we calculated and compared temperature independent emission estimates with a maximum feasible temperature dependent emission, based on the thermodynamic dissociation and solubility equilibria. Using the temperature independent approach, we estimate global NH3 emissions from seabird colonies at 404 Gg NH3 per year. By comparison, since most seabirds are located in relatively cold circumpolar locations, the thermodynamically dependent estimate is 136 Gg NH3 per year. Actual global emissions are expected to be within these bounds, as other factors, such as non-linear interactions with water availability and surface infiltration, moderate the theoretical temperature response. Combining sources of error from temperature (±49%), seabird population estimates (±36%), variation in diet composition (±23%) and non-breeder attendance (±13%), gives a mid estimate with an overall uncertainty range of NH3 emission from seabird colonies of 270 [97-442] Gg NH3 per year. These emissions are environmentally relevant as they primarily occur as "hot-spots" in otherwise pristine environments with low anthropogenic

  19. EXPANDING THE AREA OF DISTRIBUTION OF EUFRIESEA FRAGROCARA KIMSEY (HYMENOPTERA, APIDAE IN THE BRAZILIAN AMAZON FOREST

    Directory of Open Access Journals (Sweden)

    M. H. S. Souza

    2015-02-01

    Full Text Available The expansion of agriculture in the Arc of Deforestation causes deforestation and habitat loss. Euglossines sampling was done near Juruena River, Cotriguaçu municipality, northern Mato Grosso State. The bees were collected on understory and canopy using different baits. A total of 41 males of Eufriesea fragrocara Kimsey were collected. This is a rare species in collections and catalogued only in Huánuco (Peru, Napo (Ecuador, Ouro Preto D’Oeste and Ariquemes, Rondônia, Brazil. This new records increase the geographic distribution of E. fragrocara in 500 km to the western Amazon Basin, reducing the filling gaps in their distribution range in the Neotropics.

  20. Jupiter's global ammonia distribution inferred from Juno Microwave Radiometer Observations

    Science.gov (United States)

    Li, Cheng; Ingersoll, Andrew; Ewald, Shawn; Oyafuso, Fabiano; Janssen, Michael

    2017-04-01

    The Juno microwave radiometer (Juno/MWR) has made several observations of Jupiter's atmosphere by measuring the thermal emission from pressure levels down to a few hundred bars. The main objective of Juno/MWR is to determine Jupiter's deep water abundance because water is the key to understand Jovian meteorology that we observe at the cloud level, and because the deep water abundance hints at a giant planet's volatile and heavy element history. Since ammonia is the major opacity source in the Juno/MWR channels, it is especially important to figure out the ammonia distribution before we can conclude anything on the water abundance. At this stage of our analysis, we have inverted a global map (vertical and latitudinal) of ammonia distribution from the observed brightness temperatures at six wavelengths using the Markov Chain Monte Carlo technique. This method fully calibrates error and explores a wide range of the parameter space to avoid falling into a local minimum. The robustness of the retrieval is explained by matching the features in the ammonia distribution with the features in the microwave spectra. We will also announce the initial result of the retrieval of water abundance using the same technique.

  1. Eolian intracrater deposits on Mars - Physical properties and global distribution

    Science.gov (United States)

    Christensen, P. R.

    1983-01-01

    It is noted that more than one-fourth of all craters larger than 25 km in diameter between -50 deg S and 50 deg N have localized deposits of coarse material on the floor which are associated with the dark 'splotches' that are seen visually. If homogeneous, unconsolidated materials are assumed, the measured thermal inertias of these deposits imply effective grain sizes that range from 0.1 mm to 1 cm, with a modal value of 0.9 mm. Even though these deposits are coarser and darker than the surrounding terrains and the greater part of the Martian surface, they are not compositionally distinct from materials with similar albedos. It is thought most likely that these features were formed by entrapment of marginally mobile material that can be transported into, but not out of, crater depressions by the wind. Most of the 'splotch' deposits are coarser than the dune-forming materials occurring in the north polar region and inside extreme southern latitude craters; they probably form low, broad zibar dunes or lag deposits. The distribution of intracrater deposits is seen as suggesting that the intracrater features have been buried in the interior of Arabia and that the dust deposit is less extensive at the margins and may currently be expanding.

  2. Climatic controls on the global distribution, abundance, and species richness of mangrove forests

    Science.gov (United States)

    Osland, Michael J.; Feher, Laura C.; Griffith, Kereen; Cavanaugh, Kyle C.; Enwright, Nicholas M.; Day, Richard H.; Stagg, Camille L.; Krauss, Ken W.; Howard, Rebecca J.; Grace, James B.; Rogers, Kerrylee

    2017-01-01

    Mangrove forests are highly productive tidal saline wetland ecosystems found along sheltered tropical and subtropical coasts. Ecologists have long assumed that climatic drivers (i.e., temperature and rainfall regimes) govern the global distribution, structure, and function of mangrove forests. However, data constraints have hindered the quantification of direct climate-mangrove linkages in many parts of the world. Recently, the quality and availability of global-scale climate and mangrove data have been improving. Here, we used these data to better understand the influence of air temperature and rainfall regimes upon the distribution, abundance, and species richness of mangrove forests. Although our analyses identify global-scale relationships and thresholds, we show that the influence of climatic drivers is best characterized via regional range limit-specific analyses. We quantified climatic controls across targeted gradients in temperature and/or rainfall within 14 mangrove distributional range limits. Climatic thresholds for mangrove presence, abundance, and species richness differed among the 14 studied range limits. We identified minimum temperature-based thresholds for range limits in eastern North America, eastern Australia, New Zealand, eastern Asia, eastern South America, and southeast Africa. We identified rainfall-based thresholds for range limits in western North America, western Gulf of Mexico, western South America, western Australia, Middle East, northwest Africa, east central Africa, and west central Africa. Our results show that in certain range limits (e.g., eastern North America, western Gulf of Mexico, eastern Asia), winter air temperature extremes play an especially important role. We conclude that rainfall and temperature regimes are both important in western North America, western Gulf of Mexico, and western Australia. With climate change, alterations in temperature and rainfall regimes will affect the global distribution, abundance, and

  3. Global distribution and drivers of language extinction risk

    DEFF Research Database (Denmark)

    Amano, Tatsuya; Sandel, Brody; Eager, Heidi

    2014-01-01

    latitudes and are strongly linked to high economic growth. Threatened languages are numerous in the tropics, the Himalayas and northwestern North America. These results indicate that small-population languages remaining in economically developed regions are seriously threatened by continued speaker declines....... However, risks of future language losses are especially high in the tropics and in the Himalayas, as these regions harbour many small-population languages and are undergoing rapid economic growth.......Many of the world's languages face serious risk of extinction. Efforts to prevent this cultural loss are severely constrained by a poor understanding of the geographical patterns and drivers of extinction risk. We quantify the global distribution of language extinction risk-represented by small...

  4. Global distribution and conservation of evolutionary distinctness in birds.

    Science.gov (United States)

    Jetz, Walter; Thomas, Gavin H; Joy, Jeffrey B; Redding, David W; Hartmann, Klaas; Mooers, Arne O

    2014-05-05

    Integrated, efficient, and global prioritization approaches are necessary to manage the ongoing loss of species and their associated function. "Evolutionary distinctness" measures a species' contribution to the total evolutionary history of its clade and is expected to capture uniquely divergent genomes and functions. Here we demonstrate how such a metric identifies species and regions of particular value for safeguarding evolutionary diversity. Among the world's 9,993 recognized bird species, evolutionary distinctness is very heterogeneously distributed on the phylogenetic tree and varies little with range size or threat level. Species representing the most evolutionary history over the smallest area (those with greatest "evolutionary distinctness rarity") as well as some of the most imperiled distinct species are often concentrated outside the species-rich regions and countries, suggesting they may not be well captured by current conservation planning. We perform global cross-species and spatial analyses and generate minimum conservation sets to assess the benefits of the presented species-level metrics. We find that prioritizing imperiled species by their evolutionary distinctness and geographic rarity is a surprisingly effective and spatially economical way to maintain the total evolutionary information encompassing the world's birds. We identify potential conservation gaps in relation to the existing reserve network that in particular highlight islands as effective priority areas. The presented distinctness metrics are effective yet easily communicable and versatile tools to assist objective global conservation decision making. Given that most species will remain ecologically understudied, combining growing phylogenetic and spatial data may be an efficient way to retain vital aspects of biodiversity. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  5. The global volume and distribution of modern groundwater

    Science.gov (United States)

    Gleeson, Tom; Befus, Kevin; Jasechko, Scott; Luijendijk, Elco; Cardenas, Bayani

    2017-04-01

    Groundwater is important for energy and food security, human health and ecosystems. The time since groundwater was recharged - or groundwater age - can be important for diverse geologic processes such as chemical weathering, ocean eutrophication and climate change. However, measured groundwater ages range from months to millions of years. The global volume and distribution of groundwater less than 50 years old - modern groundwater that is the most recently recharged and also the most vulnerable to global change - are unknown. Here we combine geochemical, geological, hydrologic and geospatial datasets with numerical simulations of groundwater flow and analyze tritium ages to show that less than 6% of the groundwater in the uppermost portion of Earth's landmass is modern. We find that the total groundwater volume in the upper 2 km of continental crust is approximately 22.6 million km3, of which 0.1 to 5.0 million km3 is less than 50 years old. Although modern groundwater represents a small percentage of the total groundwater on Earth, the volume of modern groundwater is equivalent to a body of water with a depth of about 3 m spread over the continents. This water resource dwarfs all other components of the active hydrologic cycle.

  6. Expanding the user base beyond HEP for the Ganga distributed analysis user interface

    Science.gov (United States)

    Currie, R.; Egede, U.; Richards, A.; Slater, M.; Williams, M.

    2017-10-01

    This document presents the result of recent developments within Ganga[1] project to support users from new communities outside of HEP. In particular I will examine the case of users from the Large Scale Survey Telescope (LSST) group looking to use resources provided by the UK based GridPP[2][3] DIRAC[4][5] instance. An example use case is work performed with users from the LSST Virtual Organisation (VO) to distribute the workflow used for galaxy shape identification analyses. This work highlighted some LSST specific challenges which could be well solved by common tools within the HEP community. As a result of this work the LSST community was able to take advantage of GridPP[2][3] resources to perform large computing tasks within the UK.

  7. Global marine plankton functional type biomass distributions: Phaeocystis spp.

    Directory of Open Access Journals (Sweden)

    C. Widdicombe

    2012-09-01

    Full Text Available The planktonic haptophyte Phaeocystis has been suggested to play a fundamental role in the global biogeochemical cycling of carbon and sulphur, but little is known about its global biomass distribution. We have collected global microscopy data of the genus Phaeocystis and converted abundance data to carbon biomass using species-specific carbon conversion factors. Microscopic counts of single-celled and colonial Phaeocystis were obtained both through the mining of online databases and by accepting direct submissions (both published and unpublished from Phaeocystis specialists. We recorded abundance data from a total of 1595 depth-resolved stations sampled between 1955–2009. The quality-controlled dataset includes 5057 counts of individual Phaeocystis cells resolved to species level and information regarding life-stages from 3526 samples. 83% of stations were located in the Northern Hemisphere while 17% were located in the Southern Hemisphere. Most data were located in the latitude range of 50–70° N. While the seasonal distribution of Northern Hemisphere data was well-balanced, Southern Hemisphere data was biased towards summer months. Mean species- and form-specific cell diameters were determined from previously published studies. Cell diameters were used to calculate the cellular biovolume of Phaeocystis cells, assuming spherical geometry. Cell biomass was calculated using a carbon conversion factor for prymnesiophytes. For colonies, the number of cells per colony was derived from the colony volume. Cell numbers were then converted to carbon concentrations. An estimation of colonial mucus carbon was included a posteriori, assuming a mean colony size for each species. Carbon content per cell ranged from 9 pg C cell−1 (single-celled Phaeocystis antarctica to 29 pg C cell−1 (colonial Phaeocystis globosa. Non-zero Phaeocystis cell biomasses (without mucus carbon range from 2.9 × 10−5 to 5.4 × 103 μg C l−1, with a mean of 45.7 μg C

  8. Expanding the Range of Plant Functional Diversity Represented in Global Vegetation Models: Towards Lineage-based Plant Functional Types

    Science.gov (United States)

    Still, C. J.; Griffith, D.; Edwards, E.; Forrestel, E.; Lehmann, C.; Anderson, M.; Craine, J.; Pau, S.; Osborne, C.

    2014-12-01

    Variation in plant species traits, such as photosynthetic and hydraulic properties, can indicate vulnerability or resilience to climate change, and feed back to broad-scale spatial and temporal patterns in biogeochemistry, demographics, and biogeography. Yet, predicting how vegetation will respond to future environmental changes is severely limited by the inability of our models to represent species-level trait variation in processes and properties, as current generation process-based models are mostly based on the generalized and abstracted concept of plant functional types (PFTs) which were originally developed for hydrological modeling. For example, there are close to 11,000 grass species, but most vegetation models have only a single C4 grass and one or two C3 grass PFTs. However, while species trait databases are expanding rapidly, they have been produced mostly from unstructured research, with a focus on easily researched traits that are not necessarily the most important for determining plant function. Additionally, implementing realistic species-level trait variation in models is challenging. Combining related and ecologically similar species in these models might ameliorate this limitation. Here we argue for an intermediate, lineage-based approach to PFTs, which draws upon recent advances in gene sequencing and phylogenetic modeling, and where trait complex variations and anatomical features are constrained by a shared evolutionary history. We provide an example of this approach with grass lineages that vary in photosynthetic pathway (C3 or C4) and other functional and structural traits. We use machine learning approaches and geospatial databases to infer the most important environmental controls and climate niche variation for the distribution of grass lineages, and utilize a rapidly expanding grass trait database to demonstrate examples of lineage-based grass PFTs. For example, grasses in the Andropogoneae are typically tall species that dominate wet and

  9. Global distribution and drivers of language extinction risk.

    Science.gov (United States)

    Amano, Tatsuya; Sandel, Brody; Eager, Heidi; Bulteau, Edouard; Svenning, Jens-Christian; Dalsgaard, Bo; Rahbek, Carsten; Davies, Richard G; Sutherland, William J

    2014-10-22

    Many of the world's languages face serious risk of extinction. Efforts to prevent this cultural loss are severely constrained by a poor understanding of the geographical patterns and drivers of extinction risk. We quantify the global distribution of language extinction risk-represented by small range and speaker population sizes and rapid declines in the number of speakers-and identify the underlying environmental and socioeconomic drivers. We show that both small range and speaker population sizes are associated with rapid declines in speaker numbers, causing 25% of existing languages to be threatened based on criteria used for species. Language range and population sizes are small in tropical and arctic regions, particularly in areas with high rainfall, high topographic heterogeneity and/or rapidly growing human populations. By contrast, recent speaker declines have mainly occurred at high latitudes and are strongly linked to high economic growth. Threatened languages are numerous in the tropics, the Himalayas and northwestern North America. These results indicate that small-population languages remaining in economically developed regions are seriously threatened by continued speaker declines. However, risks of future language losses are especially high in the tropics and in the Himalayas, as these regions harbour many small-population languages and are undergoing rapid economic growth.

  10. Pan Genome of the Phytoplankton Emiliania Underpins its Global Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Read, Betsy A. [California State Univ. (CalState), San Marcos, CA (United States); Kegel, Jessica [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Klute, Mary J. [Univ. of Alberta, Edmonton, AB (Canada); Kuo, Alan [USDOE Joint Genome Inst., Walnut Creek, CA (United States); Lefebvre, Stephane C. [J. Craig Venter Inst., San Diego, CA (United States); Maumus, Florian [National Institute of Agricultural Research, Versailles (France); Mayer, Christoph [Alexander Koenig Research Museum, Bonn (Germany); Ruhr Univ., Bochum (Germany); Miller, John [Univ. of Maryland, College Park, MD (United States); Monier, Adam [Monterey Bay Aquarium Research Inst., Moss Landing, CA (United States); Salamov, Asaf [USDOE Joint Genome Inst., Walnut Creek, CA (United States); Young, Jeremy [Univ. College London (United Kingdom); Aguilar, Maria [Univ. of Alberta, Edmonton, AB (Canada); Claverie, Jean-Michel [Aix-Marseille Univ. (France); Frickenhaus, Stephan [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Univ. of Bremerhaven (Germany); Gonzalez, Karina [Harvard Medical School, Boston, MA (United States); Herman, Emily K. [Univ. of Alberta, Edmonton, AB (Canada); Lin, Yao-Cheng [Ghent Univ. (Belgium); Napier, Johnathan [Rothamstead Research, Harpenden (United Kingdom); Ogata, Hiroyuki [Aix-Marseille Univ. (France); Sarno, Analissa F. [California State Univ. (CalState), San Marcos, CA (United States); Schmutz, Jeremy [USDOE Joint Genome Inst., Walnut Creek, CA (United States); HudsonAlpha Genome Sequencing Center, Huntsville, AL (United States); Schroeder, Declan [Marine Biological Association of the UK, Plymouth (United Kingdom); de Vargas, Columban [CNRS. Univ. Pierre and Marie Curie (France).; Verret, Frederic [Univ. of Essex, Colchester (United Kingdom); von Dassow, Peter [Pontifical Catholic University of Chile, Santiago (Chile); Valentin, Klaus [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Van de Peer, Yves [Ghent Univ. (Belgium); Wheeler, Glen [Marine Biological Association of the UK, Plymouth (United Kingdom); Plymouth Marine Lab. (United Kingdom); Annotation Consortium, Emiliania huxleyi; Dacks, Joel B. [Univ. of Alberta, Edmonton, AB (Canada); Delwiche, Charles F. [Univ. of Maryland, College Park, MD (United States); Dyhrman, Sonya T. [Woods Hole Oceanographic Inst., MA (United States); Columbia Univ., Palisades, NY (United States); Glockner, Gernot [Univ. of Cologne (Germany); John, Uwe [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Richards, Thomas [National History Museum, London (United Kingdom); Worden, Alexandra Z. [Monterey Bay Aquarium Research Inst., Moss Landing, CA (United States); Zhang, Xiaoyu [California State Univ. (CalState), San Marcos, CA (United States); Grigoriev, Igor V. [USDOE Joint Genome Inst., Walnut Creek, CA (United States)

    2012-06-18

    Coccolithophores have influenced the global climate for over 200 million years1. These marine phytoplankton can account for 20 per cent of total carbon fixation in some systems2. They form blooms that can occupy hundreds of thousands of square kilometres and are distinguished by their elegantly sculpted calcium carbonate exoskeletons (coccoliths), rendering themvisible fromspace3.Although coccolithophores export carbon in the form of organic matter and calcite to the sea floor, they also release CO2 in the calcification process. Hence, they have a complex influence on the carbon cycle, driving either CO2 production or uptake, sequestration and export to the deep ocean4. Here we report the first haptophyte reference genome, from the coccolithophore Emiliania huxleyi strain CCMP1516, and sequences from 13 additional isolates. Our analyses reveal a pan genome (core genes plus genes distributed variably between strains) probably supported by an atypical complement of repetitive sequence in the genome. Comparisons across strains demonstrate thatE. huxleyi, which has long been considered a single species, harbours extensive genome variability reflected in different metabolic repertoires. Genome variability within this species complex seems to underpin its capacity both to thrive in habitats ranging from the equator to the subarctic and to form large-scale episodic blooms under a wide variety of environmental conditions.

  11. Intense Collaboration In Globally Distributed Teams: Evolving Patterns Of Dependencies And Coordination

    NARCIS (Netherlands)

    K. Kumar (Kuldeep); P.C. van Fenema (Paul); M.A. von Glinow

    2004-01-01

    textabstractAs multi-national firms and major offshore outsourcing companies develop experience with global work, their globally distributed teams face the challenge of collaborating intensely without the common interaction advantages associated with collocated work. This chapter analyzes the

  12. The Global Distribution of Ecosystems in a World without Fire

    National Research Council Canada - National Science Library

    W. J. Bond; F. I. Woodward; G. F. Midgley

    2005-01-01

    • This paper is the first global study of the extent to which fire determines global vegetation patterns by preventing ecosystems from achieving the potential height, biomass and dominant functional...

  13. Global geographic distribution of Trichinella species and genotypes.

    Science.gov (United States)

    Feidas, Haralambos; Kouam, Marc K; Kantzoura, Vaia; Theodoropoulos, Georgios

    2014-08-01

    Maximum entropy ecological niche modeling was utilized to describe the global geographic distribution of Trichinella species and genotypes and to assess their invasive risk in new areas other than the ones currently known. Also, space-time scan statistic was utilized to identify global spatiotemporal clusters of infection. A database containing 3209 records for 12 species and genotypes identified at the International Trichinella Reference Center (ITRC) as well as climate, elevation, and land cover data extracted from various databases were used. Ecological niche modeling implemented in the Maxent program indicated new potential ranges for T. spiralis (T1), T. nativa (T2), T. britovi (T3), T. pseudospiralis (T4), T. murrelli (T5), T6, T. papuae (T10), and T. zimbabwensis (T11). The area under the curve values for the test data of the models ranged from 0.901 to 0.998, indicating that the models were very good to excellent. The most important bioclimatic factor in modeling the ranges for T. spiralis (T1), T. nativa (T2), T. britovi (T3), T6, and T. zimbabwensis (T11) was temperature, for T. pseudospiralis (T4) and T. papuae (T10) was precipitation, and for T. murrelli (T5) was land cover. T. spiralis (T1), T. britovi (T3), and T. pseudospiralis (T4) had the same primary land cover which was "Grass Crops". The primary land covers were "Conifer Boreal Forest" for T. nativa (T2), "Cool Fields and Woods" for T. murrelli (T5), "Upland Tundra" for T6, "Tropical Rainforest" for T. papuae (T10), and "Crops and Town" for T. zimbabwensis (T11). The scan statistic analyses revealed the presence of significant spatiotemporal clusters (p<0.05) for T. spiralis (T1), T. nativa (T2), T. britovi (T3), T. pseudospiralis (T4), T. murrelli (T5), T6, and T. nelsoni (T7). No significant clusters were found for T. papuae (T10) and T. zimbabwensis (T11). Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Social Epidemiology and Global Mental Health: Expanding the Evidence from High-Income to Low- and Middle-Income Countries.

    Science.gov (United States)

    Maselko, Joanna

    2017-01-01

    The vast majority of research on the social determinants of mental health has been generated from high-income country (HIC) populations, even as the greatest health disparities, and greatest disease burden, is observed in lower- and middle-income countries (LMICs). The goal of this review is to examine the evidence base on how key social epidemiology constructs relate to mental health in LMIC contexts. A special focus is on points of departure from the HIC knowledge base, gaps in overall understanding, and opportunities for social epidemiology to make a significant contribution. A growing body of literature suggests that there is significant heterogeneity, both in the direction and magnitude, of association between factors such as socioeconomic status, income inequality, gender, and social networks/supports and mental health in LMIC. For example, higher levels of education and being married can be risk factors for worse mental health among women in certain contexts. However, many studies have methodological limitations that make causal inference difficult. Poverty alleviation interventions offer a unique opportunity to examine the impact of improving economic resources and mental health. Much remains unknown about the impact of key social factors on mental health in LMIC. Findings from HICs may not apply to LMIC populations, since the meaning and distribution of a given social variable may differ significantly from what is commonly observed in HICs. These points of departure point to opportunities for social epidemiology to make a contribution to the field of global mental health.

  15. Worldwide distribution of non–native Amazon parrots and temporal trends of their global trade

    Directory of Open Access Journals (Sweden)

    Mori, E.

    2017-01-01

    Full Text Available Alien species are the second leading cause of the global biodiversity crisis, after habitat loss and fragmentation. Popular pet species, such as parrots and parakeets (Aves, Psittaciformes, are often introduced outside their native range as a result of the pet trade. On escape from captivity, some such species, such as the ring–necked parakeet and the monk parakeet, are highly invasive and successfully compete with native species. Populations of Amazon parrots (Amazona spp. can be found throughout the world, but data on their status, distribution and impact are incomplete. We gathered and reviewed the available information concerning global trade, distribution, abundance and ecology of Amazon parrots outside their native range. Our review shows that at least nine species of Amazon parrots have established populations outside their original range of occurrence throughout the world (in Europe, South Africa, the Caribbean islands, Hawaii, and North and South America. Their elusive behaviour and small population size suggest that the number of alien nuclei could be underestimated or at undetected. Despite international trade bans, the large trade of wild–caught Amazon parrots in past decades appears to have contributed to the establishment of alien populations worldwide. Establishment success seems to differ geographically. While European populations are still small and growing slowly, USA populations are large and expanding geographically. This difference is not related to large propagule pressure (trade but possibly to a better niche match between native and introduced ranges. Amazona aestiva is the most frequently encountered Amazona parrot, with at least eight alien populations reported to date. All these populations, with the exception of those in the USA where the climate is more suitable for their establishment, are composed of a low number of individuals even though they have been established for a long period of time. Further research

  16. Six Classic Distribution Paradigms for Global Marketing Channel Strategy

    OpenAIRE

    Rosenbloom, Bert

    2010-01-01

    Global marketing has become an established fact of life for more and more businesses. Along with the large multinational corporations that have been operating on a global scale for decades, many middle market or even relatively small firms have already or will soon need to enter the global marketplace to enhance their long-term viability (Czinkota et al 1995). The growth of Internetbased e-commerce has accelerated this global trend. Marketing channels which provide the institutional structure...

  17. The development and distribution of NASA's global differential system

    Science.gov (United States)

    Bar-Sever, Y.; Muellerschoen, R.; Reichert, A.; Vozoff, M.; Young, L.

    2001-01-01

    We describe the development, demonstration, and applications of the NASA Global Differential GPS (GDGPS) system, an effort that is funded under the Advanced Information Systems Technology (AIST) Program.

  18. Global evidence on the distribution of GDP growth rates

    Science.gov (United States)

    Williams, Michael A.; Baek, Grace; Li, Yiyang; Park, Leslie Y.; Zhao, Wei

    2017-02-01

    We study the size distribution of changes in the gross domestic product (GDP) of 167 countries for the period 1950-2011. A consensus has developed in the literature that the distribution of GDP growth rates can be approximated by the Laplace distribution in the central part and power-law distributions in the tails. Using a richer database than prior studies and testing for more theoretical distributions, we find that the distribution of GDP growth rates can be fitted using the heavy-tailed Cauchy distribution for almost all countries. Significantly, this same finding recently has been demonstrated for (1) the distribution of firm growth rates and (2) the distribution of firm economic profit rates. Together, these three findings suggest the possibility that there exist universal mechanisms that give rise to general laws governing the growth dynamics of firms and economies.

  19. Global distribution of consanguinity and their impact on complex ...

    African Journals Online (AJOL)

    Abdulbari Bener

    Global impact. Complex diseases. Counseling. a b s t r a c t. Background: Marriage between close relatives has been practised globally since the early existence of human society. The role of consanguinity and inbreeding affecting human health is a topic of great inter- est in medical genetics. Objective: The objective of the ...

  20. Constraint-based query distribution framework for an integrated global schema

    DEFF Research Database (Denmark)

    Malik, Ahmad Kamran; Qadir, Muhammad Abdul; Iftikhar, Nadeem

    2009-01-01

    and replicated data sources. The provided system is all XML-based which poses query in XML form, transforms, and integrates local results in an XML document. Contributions include the use of constraints in our existing global schema which help in source selection and query optimization, and a global query...... distribution framework for querying distributed heterogeneous data sources....

  1. Global Distribution of Fine Root Biomass in Terrestrial Ecosystems

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: A global data set of root biomass, rooting profiles, and concentrations nutrients in roots was compiled from the primary literature and used to study...

  2. Global Distribution of Root Profiles in Terrestrial Ecosystems

    Data.gov (United States)

    National Aeronautics and Space Administration — Rooting depths were estimated from a global database of root profiles assembled from the primary literature to study relationships of abiotic and biotic factors...

  3. Possible implications of global climate change on global lightning distributions and frequencies

    Science.gov (United States)

    Price, Colin; Rind, David

    1994-01-01

    The Goddard Institute for Space Studies (GISS) general circulation model (GCM) is used to study the possible implications of past and future climate change on global lightning frequencies. Two climate change experiments were conducted: one for a 2 x CO2 climate (representing a 4.2 degs C global warming) and one for a 2% decrease in the solar constant (representing a 5.9 degs C global cooling). The results suggest at 30% increase in global lightning activity for the warmer climate and a 24% decrease in global lightning activity for the colder climate. This implies an approximate 5-6% change in global lightning frequencies for every 1 degs C global warming/cooling. Both intracloud and cloud-to-ground frequencies are modeled, with cloud-to-ground lightning frequencies showing larger sensitivity to climate change than intracloud frequencies. The magnitude of the modeled lightning changes depends on season, location, and even time of day.

  4. Distributed Global Transaction Support for Workflow Management Applications

    NARCIS (Netherlands)

    Vonk, J.; Grefen, P.W.P.J.; Boertjes, E.M.; Apers, Peter M.G.

    Workflow management systems require advanced transaction support to cope with their inherently long-running processes. The recent trend to distribute workflow executions requires an even more advanced transaction support system that is able to handle distribution. This paper presents a model as well

  5. Distributed Global Transaction Support for Workflow Management Applications

    NARCIS (Netherlands)

    Vonk, J.; Grefen, P.W.P.J.; Boertjes, E.M.; Apers, Peter M.G.

    Workflow management systems require advanced transaction support to cope with their inherently long-running processes. The recent trend to distribute workflow executions requires an even more advanced transaction support system that is able to handle distribution. This report presents a model as

  6. Improving Department of Defense Global Distribution Performance Through Network Analysis

    Science.gov (United States)

    2016-06-01

    Scheduled MILAIR Local Truck Unknown Ocean Scheduled Truck Other THEATER Central Germany Puerto Rico West Spain Virgin Islands Southeast Turkey Mexico ...changing modes” (p. 324). For example multiple packages consolidated in a shipping container, the container then being transported to a port by truck ...JDDE. Other organizations conduct distribution execution. In the role of Distribution Process Manager, it contracts companies like UPS, and similar

  7. Assessment of hypoglycaemia during basal insulin therapy: Temporal distribution and risk of events using a predefined or an expanded definition of nocturnal events.

    Science.gov (United States)

    Riddle, M C; Bolli, G B; Avogaro, A; Álvarez, M G; Merino-Trigo, A; Boëlle-Le Corfec, E; Home, P D

    2017-12-11

    To describe in type 2 diabetes the 24-hour distribution of hypoglycaemia and compare the frequency of nocturnal events based on a predefined nocturnal window or an expanded interval, using illustrative data for two insulin glargine formulations. Temporal distribution of hypoglycaemic events was assessed descriptively and by profile using participant-level data from three randomized trials comparing insulin glargine 300 U/mL (Gla-300) and 100 U/mL (Gla-100). Risk of hypoglycaemia and annualized event rates were compared for the predefined nocturnal interval (00:00 to 05:59h) and an expanded window (22:00h to the pre-breakfast glucose measurement). Confirmed (≤3.9mmol/L [≤70 mg/dL]) or severe hypoglycaemic events were reported most frequently between 06:00 and 10:00 h with both insulins. Nearly threefold more events were identified using the expanded nocturnal interval. Risk of ≥1 nocturnal event was 25% lower with Gla-300 than Gla-100 with the predefined, and 16% lower with the expanded interval; annualized event rates were 31% and 24% lower with the predefined and expanded window, respectively. The between-insulin difference in number of nocturnal events depended markedly on the chosen nocturnal interval (556 vs. 1145 fewer events with Gla-300 using the predefined vs. expanded interval). The predefined 00:00-05:59h nocturnal interval excluded many hypoglycaemic events occurring during the actual overnight interval. While Gla-300 reduced hypoglycaemic events versus Gla-100 (regardless of the interval considered), the results obtained using the expanded window better reflect the clinical experience of people treated with basal insulin. Copyright © 2017. Published by Elsevier Masson SAS.

  8. The Possibility Of The Strict Global Thermodynamic Equilibrium In The Expanding Universe At Presence Of The Fundamental Scalar Field

    CERN Document Server

    Ignat'ev, Yurii

    2014-01-01

    In the article it is shown that at presence of fundamental scalar fields determining the masses of the scalar charged particles the global thermodynamic equilibrium (GTE) is compatible with a process of the cosmological expansion of the statistical system.

  9. Expanding Global Production Networks: The emergence, evolution and the developmental impact of the offshore service sector in the Philippines

    NARCIS (Netherlands)

    Kleibert, J.M.

    2015-01-01

    Contemporary globalisation is characterised by an expansion of global production networks in services. Developments in information and communications technology have enabled the relocation of services across national borders, or, the offshoring of services. This has had profound implications for

  10. Global distribution of pauses observed with satellite measurements

    Indian Academy of Sciences (India)

    1National Atmospheric Research Laboratory, Gadanki, Tirupati 517 502, India. 2Department of Earth ... Prior to the 1990's ground-based instruments, .... of various datasets used for the present study, its global co verage, altitude co verage, duration o f o bservations considered, their a ccuracies, basic principle u sed to get.

  11. The global distribution of the Duffy blood group

    Science.gov (United States)

    Howes, Rosalind E.; Patil, Anand P.; Piel, Frédéric B.; Nyangiri, Oscar A.; Kabaria, Caroline W.; Gething, Peter W.; Zimmerman, Peter A.; Barnadas, Céline; Beall, Cynthia M.; Gebremedhin, Amha; Ménard, Didier; Williams, Thomas N.; Weatherall, David J.; Hay, Simon I.

    2011-01-01

    Blood group variants are characteristic of population groups, and can show conspicuous geographic patterns. Interest in the global prevalence of the Duffy blood group variants is multidisciplinary, but of particular importance to malariologists due to the resistance generally conferred by the Duffy-negative phenotype against Plasmodium vivax infection. Here we collate an extensive geo-database of surveys, forming the evidence-base for a multi-locus Bayesian geostatistical model to generate global frequency maps of the common Duffy alleles to refine the global cartography of the common Duffy variants. We show that the most prevalent allele globally was FY*A, while across sub-Saharan Africa the predominant allele was the silent FY*BES variant, commonly reaching fixation across stretches of the continent. The maps presented not only represent the first spatially and genetically comprehensive description of variation at this locus, but also constitute an advance towards understanding the transmission patterns of the neglected P. vivax malaria parasite. PMID:21468018

  12. Coordination and Control of Globally Distributed Software Projects

    NARCIS (Netherlands)

    P.C. van Fenema (Paul)

    2002-01-01

    textabstractRecently, software development and implementation projects have globalized at a rapid pace. Companies in North America, Europe, and the Far East are beginning to integrate international Information Technology (IT) resources to support operations across the globe. Offshore IT services

  13. Globalization and Conflict: Welfare, Distribution,and Political Unrest

    Directory of Open Access Journals (Sweden)

    Ranveig Gissinger

    2015-08-01

    Full Text Available The consequences of globalization for the development of a more peaceful world remain highly controversial. This article seeks to clarify the impact that the globalization of the economy may have on civil war and political instability. Liberals argue that countries heavily dependent on the global economy (whether measured by trade or investment are likely to experience higher economic growth, greater affluence, more democracy, and increasingly peaceful conditions at home and abroad. In stark contrast, most dependency theorists argue that high levels of trade and investment tend to generate greater economic inequality. Relative deprivation theory suggests that such inequality will increase the risk of political instability. From these two broad perspectives, a set of hypotheses is developed and tested on a global dataset for the period 1965-93. The consequences of an open economy prove to be quite complex. A high level of trade does generate more domestic peace; at the same time, direct foreign investment also creates conditions conducive to political instability. However, the consequences of trade are dependent on what is being exported. Exports of manufactured goods create high levels of welfare and equality, while exports of agricultural products promote poverty and inequality. Inequality emerges as but one of many factors which lead to political instability.

  14. Origin, dispersal and current global distribution of cacao genetic diversity

    Science.gov (United States)

    Cacao (Theobroma cacao L.) is cultivated globally as the unique source of cocoa butter and powder for the confectionery industries. In spite of its economical importance, cocoa was and continues to be dominantly produced in low-input and low-output systems. Production constraints, including depletio...

  15. Global Distribution of Active Volcanism on Io as Known at the End of the Galileo Mission

    Science.gov (United States)

    Lopes, Rosaly M. C.; Kamp. Lucas W.; Smythe, W. D.; Radebaugh, J.; Turtle, E.; Perry, J.; Bruno, B.

    2004-01-01

    Hot spots are manifestations of Io s mechanism of internal heating and heat transfer. Therefore, the global distribution of hot spots and their power output has important implications for how Io is losing heat. The end of the Galileo mission is an opportune time to revisit studies of the distribution of hot spots on Io, and to investigate the distribution of their power output.

  16. Global distribution of Earth's surface shortwave radiation budget

    Directory of Open Access Journals (Sweden)

    N. Hatzianastassiou

    2005-01-01

    Full Text Available The monthly mean shortwave (SW radiation budget at the Earth's surface (SRB was computed on 2.5-degree longitude-latitude resolution for the 17-year period from 1984 to 2000, using a radiative transfer model accounting for the key physical parameters that determine the surface SRB, and long-term climatological data from the International Satellite Cloud Climatology Project (ISCCP-D2. The model input data were supplemented by data from the National Centers for Environmental Prediction - National Center for Atmospheric Research (NCEP-NCAR and European Center for Medium Range Weather Forecasts (ECMWF Global Reanalysis projects, and other global data bases such as TIROS Operational Vertical Sounder (TOVS and Global Aerosol Data Set (GADS. The model surface radiative fluxes were validated against surface measurements from 22 stations of the Baseline Surface Radiation Network (BSRN covering the years 1992-2000, and from 700 stations of the Global Energy Balance Archive (GEBA, covering the period 1984-2000. The model is in good agreement with BSRN and GEBA, with a negative bias of 14 and 6.5 Wm-2, respectively. The model is able to reproduce interesting features of the seasonal and geographical variation of the surface SW fluxes at global scale. Based on the 17-year average model results, the global mean SW downward surface radiation (DSR is equal to 171.6 Wm-2, whereas the net downward (or absorbed surface SW radiation is equal to 149.4 Wm-2, values that correspond to 50.2 and 43.7% of the incoming SW radiation at the top of the Earth's atmosphere. These values involve a long-term surface albedo equal to 12.9%. Significant increasing trends in DSR and net DSR fluxes were found, equal to 4.1 and 3.7 Wm-2, respectively, over the 1984-2000 period (equivalent to 2.4 and 2.2 Wm-2 per decade, indicating an increasing surface solar radiative heating. This surface SW radiative heating is primarily attributed to clouds, especially low-level, and secondarily to

  17. Peripheral cinematographies in the global distribution system: structural tensions

    National Research Council Canada - National Science Library

    Josetxo Cerdán Los Arcos

    2004-01-01

    The article proposes an approach to the critical discourses that are generated in the film distribution processes, and it focusses its analysis on the case of minority, peripheral and quality-orientated cinemas...

  18. The Logistic Centre, Expression of the Distribution Globalization

    OpenAIRE

    Gheorghe Dan

    2010-01-01

    Within the current market expansion and globalisation of the product distribution, which becomes an essential element of the economic and social International Systems, their specific economic acitivities and the modern trend have made possible the building of different trade channels. Based on this theory the logistics centers - Strategical Investment Projects, enables the implementation of the most advanced tehnologies within merchandise logistics and distribution, achieving economical effic...

  19. Toward Global Drought Early Warning Capability - Expanding International Cooperation for the Development of a Framework for Monitoring and Forecasting

    Science.gov (United States)

    Pozzi, Will; Sheffield, Justin; Stefanski, Robert; Cripe, Douglas; Pulwarty, Roger; Vogt, Jurgen V.; Heim, Richard R., Jr.; Brewer, Michael J.; Svoboda, Mark; Westerhoff, Rogier; hide

    2013-01-01

    Drought has had a significant impact on civilization throughout history in terms of reductions in agricultural productivity, potable water supply, and economic activity, and in extreme cases this has led to famine. Every continent has semiarid areas, which are especially vulnerable to drought. The Intergovernmental Panel on Climate Change has noted that average annual river runoff and water availability are projected to decrease by 10 percent-13 percent over some dry and semiarid regions in mid and low latitudes, increasing the frequency, intensity, and duration of drought, along with its associated impacts. The sheer magnitude of the problem demands efforts to reduce vulnerability to drought by moving away from the reactive, crisis management approach of the past toward a more proactive, risk management approach that is centered on reducing vulnerability to drought as much as possible while providing early warning of evolving drought conditions and possible impacts. Many countries, unfortunately, do not have adequate resources to provide early warning, but require outside support to provide the necessary early warning information for risk management. Furthermore, in an interconnected world, the need for information on a global scale is crucial for understanding the prospect of declines in agricultural productivity and associated impacts on food prices, food security, and potential for civil conflict. This paper highlights the recent progress made toward a Global Drought Early Warning Monitoring Framework (GDEWF), an underlying partnership and framework, along with its Global Drought Early Warning System (GDEWS), which is its interoperable information system, and the organizations that have begun working together to make it a reality. The GDEWF aims to improve existing regional and national drought monitoring and forecasting capabilities by adding a global component, facilitating continental monitoring and forecasting (where lacking), and improving these tools at

  20. Peripheral cinematographies in the global distribution system: structural tensions

    Directory of Open Access Journals (Sweden)

    Josetxo Cerdán Los Arcos

    2004-10-01

    Full Text Available The article proposes an approach to the critical discourses that are generated in the film distribution processes, and it focusses its analysis on the case of minority, peripheral and quality-orientated cinemas. While much is known about the processes through whichthe so-called commercial films arrive in movie theatres, there are few studies that delve into the distribution conditions of minority cinemas (as if their distribution process could come about in a naturalised way, due to these theatres’ goodness. Nothing could be further from the truth. The circulation of these films originates from very concrete representations, which emanate from some specific centres, and they are the ones that end up configuring the terrain of uses and abuses for the consumption of these films.

  1. Statistical modelling of a new global potential vegetation distribution

    Science.gov (United States)

    Levavasseur, G.; Vrac, M.; Roche, D. M.; Paillard, D.

    2012-12-01

    The potential natural vegetation (PNV) distribution is required for several studies in environmental sciences. Most of the available databases are quite subjective or depend on vegetation models. We have built a new high-resolution world-wide PNV map using a objective statistical methodology based on multinomial logistic models. Our method appears as a fast and robust alternative in vegetation modelling, independent of any vegetation model. In comparison with other databases, our method provides a realistic PNV distribution in agreement with respect to BIOME 6000 data. Among several advantages, the use of probabilities allows us to estimate the uncertainty, bringing some confidence in the modelled PNV, or to highlight the regions needing some data to improve the PNV modelling. Despite our PNV map being highly dependent on the distribution of data points, it is easily updatable as soon as additional data are available and provides very useful additional information for further applications.

  2. Generation of real-time global ionospheric map based on the global GNSS stations with only a sparse distribution

    Science.gov (United States)

    Li, Zishen; Wang, Ningbo; Li, Min; Zhou, Kai; Yuan, Yunbin; Yuan, Hong

    2017-04-01

    The Earth's ionosphere is part of the atmosphere stretching from an altitude of about 50 km to more than 1000 km. When the Global Navigation Satellite System (GNSS) signal emitted from a satellite travels through the ionosphere before reaches a receiver on or near the Earth surface, the GNSS signal is significantly delayed by the ionosphere and this delay bas been considered as one of the major errors in the GNSS measurement. The real-time global ionospheric map calculated from the real-time data obtained by global stations is an essential method for mitigating the ionospheric delay for real-time positioning. The generation of an accurate global ionospheric map generally depends on the global stations with dense distribution; however, the number of global stations that can produce the real-time data is very limited at present, which results that the generation of global ionospheric map with a high accuracy is very different when only using the current stations with real-time data. In view of this, a new approach is proposed for calculating the real-time global ionospheric map only based on the current stations with real-time data. This new approach is developed on the basis of the post-processing and the one-day predicted global ionospheric map from our research group. The performance of the proposed approach is tested by the current global stations with the real-time data and the test results are also compared with the IGS-released final global ionospheric map products.

  3. Cosmic-Ray Extremely Distributed Observatory: a global cosmic ray detection framework

    Science.gov (United States)

    Sushchov, O.; Homola, P.; Dhital, N.; Bratek, Ł.; Poznański, P.; Wibig, T.; Zamora-Saa, J.; Almeida Cheminant, K.; Alvarez Castillo, D.; Góra, D.; Jagoda, P.; Jałocha, J.; Jarvis, J. F.; Kasztelan, M.; Kopański, K.; Krupiński, M.; Michałek, M.; Nazari, V.; Smelcerz, K.; Smolek, K.; Stasielak, J.; Sułek, M.

    2017-12-01

    The main objective of the Cosmic-Ray Extremely Distributed Observatory (CREDO) is the detection and analysis of extended cosmic ray phenomena, so-called super-preshowers (SPS), using existing as well as new infrastructure (cosmic-ray observatories, educational detectors, single detectors etc.). The search for ensembles of cosmic ray events initiated by SPS is yet an untouched ground, in contrast to the current state-of-the-art analysis, which is focused on the detection of single cosmic ray events. Theoretical explanation of SPS could be given either within classical (e.g., photon-photon interaction) or exotic (e.g., Super Heavy Dark Matter decay or annihilation) scenarios, thus detection of SPS would provide a better understanding of particle physics, high energy astrophysics and cosmology. The ensembles of cosmic rays can be classified based on the spatial and temporal extent of particles constituting the ensemble. Some classes of SPS are predicted to have huge spatial distribution, a unique signature detectable only with a facility of the global size. Since development and commissioning of a completely new facility with such requirements is economically unwarranted and time-consuming, the global analysis goals are achievable when all types of existing detectors are merged into a worldwide network. The idea to use the instruments in operation is based on a novel trigger algorithm: in parallel to looking for neighbour surface detectors receiving the signal simultaneously, one should also look for spatially isolated stations clustered in a small time window. On the other hand, CREDO strategy is also aimed at an active engagement of a large number of participants, who will contribute to the project by using common electronic devices (e.g., smartphones), capable of detecting cosmic rays. It will help not only in expanding the geographical spread of CREDO, but also in managing a large manpower necessary for a more efficient crowd-sourced pattern recognition scheme to

  4. Gas expanders at M/R Stations in the natural gas distribution network. Pre-project, subreport; Gasexpandere paa distributionsnettets M/R-stationer. Forprojekt, delrapport

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Niels Bjarne

    2010-05-15

    Danish Gas Technology Centre has been carrying out a feasibility project to clarify the possibilities of installing gas expanders at M/R-stations (Measuring and Regulating) in the Distribution system of the natural gas grid. A large number of such expanders are installed around the world. The novelty of this project is to use a heat pump to perform the necessary heating of the gas before the expander, and to ''export'' to the electricity grid the remaining electricity from the generator connected to the expander. The present project includes the small M/R-stations at the gas Distribution grid where pressure is reduced from 40 or 20 bar to 4 bar. The preliminary project (year 1 of project) has investigated whether components for such smaller systems can be found, and it has investigated prices for different quantities. A technical feasibility study has been done. Also, preliminary calculations of payback times has been carried out. A large potential of CO{sub 2}-reduction is present with this technology based on saving of natural gas combustion and on new electricity production displacing existing production without any use of primary energy. The main results and conclusions are: 1) There are component suppliers for expander systems suitable to the size of distribution network M/R stations. 2) Pressure regulators provided at the stations are laid out with significant overcapacity, enabling a simplified installation of the expander systems. 3) If the system is being rolled out across the Danish distribution grid, the realistic saving potential is approx. 2.3 million Nm3 of gas per year and a production of almost 40 million kWh of electricity. 4) If the price is 0.60 DKK/kWh for electricity sold, the simple pay-back is 6-7 years on average, covering a variation from 3 to 16 years at the various stations. The smallest stations are omitted. The best stations covering more than half of the gas flow have a pay-back time between 3 and 6 years. 5) The

  5. FORMATION OF DISTRIBUTION SYSTEMS WITH THE INVOLVEMENT OF THE GLOBAL RETAIL CHAINS

    National Research Council Canada - National Science Library

    Kudyrko, L; Sevruk, I

    2015-01-01

    The purpose of the article is to analyze the features of formation and functioning of multi-marketing distribution systems involving global retail chains and identify the causes of conflicts between...

  6. Implication of global climate change on the distribution and activity of Phytophthora ramorum

    Science.gov (United States)

    Robert C. Venette

    2009-01-01

    Global climate change is predicted to alter the distribution and activity of several forest pathogens. Boland et al. (2004) suggested that climate change might affect pathogen establishment, rate of disease progress, and the duration of...

  7. 1st International Workshop on Tools for Managing Globally Distributed Software Development (TOMAG 2007)

    NARCIS (Netherlands)

    Harmsen, Frank; van Hillegersberg, Jos; Harmsen, Frank; Amrit, Chintan Amrit; Geisberger, Eva; Keil, Patrick; Kuhrmann, Marco

    2007-01-01

    The advent of global distribution of software development has made managing collaboration and coordination among developers more difficult due to various reasons including physical distance, differences in time, cultural differences etc. A nearly total absence of informal communication among

  8. Constraint-based Query Distribution Framework for an Integrated Global Schema

    OpenAIRE

    Malik, Ahmad Kamran; Qadir, Muhammad Abdul; Iftikhar, Nadeem; Usman, Muhammad

    2010-01-01

    Distributed heterogeneous data sources need to be queried uniformly using global schema. Query on global schema is reformulated so that it can be executed on local data sources. Constraints in global schema and mappings are used for source selection, query optimization,and querying partitioned and replicated data sources. The provided system is all XML-based which poses query in XML form, transforms, and integrates local results in an XML document. Contributions include the use of constraints...

  9. Assessing a Tornado Climatology from Global Tornado Intensity Distributions.

    Science.gov (United States)

    Feuerstein, Bernold; Dotzek, Nikolai; Grieser, Jürgen

    2005-02-01

    Recent work demonstrated that the shape of tornado intensity distributions from various regions worldwide is well described by Weibull functions. This statistical modeling revealed a strong correlation between the fit parameters c for shape and b for scale regardless of the data source. In the present work it is shown that the quality of the Weibull fits is optimized if only tornado reports of F1 and higher intensity are used and that the c-b correlation does indeed reflect a universal feature of the observed tornado intensity distributions. For regions with likely supercell tornado dominance, this feature is the number ratio of F4 to F3 tornado reports R(F4/F3) = 0.238. The c-b diagram for the Weibull shape and scale parameters is used as a climatological chart, which allows different types of tornado climatology to be distinguished, presumably arising from supercell versus nonsupercell tornadogenesis. Assuming temporal invariance of the climatology and using a detection efficiency function for tornado observations, a stationary climatological probability distribution from large tornado records (U.S. decadal data 1950-99) is extracted. This can be used for risk assessment, comparative studies on tornado intensity distributions worldwide, and estimates of the degree of underreporting for areas with poor databases. For the 1990s U.S. data, a likely tornado underreporting of the weak events (F0, F1) by a factor of 2 can be diagnosed, as well as asymptotic climatological c,b values of c = 1.79 and b = 2.13, to which a convergence in the 1950-99 U.S. decadal data is verified.

  10. Cross-Cultural Management Learning through Innovative Pedagogy: An Exploratory Study of Globally Distributed Student Teams

    Science.gov (United States)

    Bartel-Radic, Anne; Moos, J. Chris; Long, Suzanna K.

    2015-01-01

    This article presents an innovative pedagogy based on student participation in globally distributed project teams. The study questions the link between student learning of intercultural competence and the global teaming experience. Data was collected from 115 students participating in 22 virtual intercultural teams. Results revealed that students…

  11. A fully traits-based approach to modeling global vegetation distribution

    NARCIS (Netherlands)

    Bodegom, van P.M.; Douma, J.C.; Verheijen, L.M.

    2014-01-01

    Dynamic Global Vegetation Models (DGVMs) are indispensable for our understanding of climate change impacts. The application of traits in DGVMs is increasingly refined. However, a comprehensive analysis of the direct impacts of trait variation on global vegetation distribution does not yet exist.

  12. Building a French for Business and Technology Program Abroad: Giving Students an Edge in an Expanding Global Job Market

    OpenAIRE

    Lemarchand, Lionel J.

    2010-01-01

    The reality of globalization has made international programs more significant than ever before. Students from all over the world are accessing an increasingly competitive world market. Understanding other cultures in the social sense and in the business culture sense is crucial not only for their own benefits but also for their careers. This article describes how to develop an “Abroad Business and Technology Program” and presents the principal components that can insure its success. It also s...

  13. Global distribution of secondary organic aerosol particle phase state

    Science.gov (United States)

    Shiraiwa, M.; Li, Y., Sr.; Tsimpidi, A.; Karydis, V.; Berkemeier, T.; Pandis, S. N.; Lelieveld, J.; Koop, T.; Poeschl, U.

    2016-12-01

    Secondary organic aerosols (SOA) account for a large fraction of submicron particles in the atmosphere and play a key role in aerosol effects on climate, air quality and public health. The formation and aging of SOA proceed through multiple steps of chemical reaction and mass transport in the gas and particle phases, which is challenging for the interpretation of field measurements and laboratory experiments as well as accurate representation of SOA evolution in atmospheric aerosol models. SOA particles can adopt liquid, semi-solid and amorphous solid (glassy) phase states depending on chemical composition, relative humidity and temperature. The particle phase state is crucial for various atmospheric gas-particle interactions, including SOA formation, heterogeneous and multiphase reactions and ice nucleation. We found that organic compounds with a wide variety of functional groups fall into molecular corridors, characterized by a tight inverse correlation between molar mass and volatility. Based on the concept of molecular corridors, we develop a method to estimate glass transition temperatures based on the molar mass and molecular O:C ratio of SOA components, which is a key property for determination of particle phase state. We use the global chemistry climate model EMAC with the organic aerosol module ORACLE to predict the atmospheric SOA phase state. For the planetary boundary layer, global simulations indicate that SOA is mostly liquid in tropical and polar air with high relative humidity, semi-solid in the mid-latitudes, and solid over dry lands. We find that in the middle and upper troposphere (>500 hPa) SOA should be mostly in a glassy solid phase state. Thus, slow diffusion of water, oxidants, and organic molecules could kinetically limit gas-particle interactions of SOA in the free and upper troposphere, promote ice nucleation and facilitate long-range transport of reactive and toxic organic pollutants embedded within SOA.

  14. Assessing a Tornado Climatology from Global Tornado Intensity Distributions

    OpenAIRE

    Feuerstein, B.; Dotzek, N.; Grieser, J.

    2005-01-01

    Recent work demonstrated that the shape of tornado intensity distributions from various regions worldwide is well described by Weibull functions. This statistical modeling revealed a strong correlation between the fit parameters c for shape and b for scale regardless of the data source. In the present work it is shown that the quality of the Weibull fits is optimized if only tornado reports of F1 and higher intensity are used and that the c–b correlation does indeed reflect a universal featur...

  15. Quantum Key Distribution with High Loss: Toward Global Secure Communication

    Science.gov (United States)

    Hwang, Won-Young

    2003-08-01

    We propose a decoy-pulse method to overcome the photon-number-splitting attack for Bennett-Brassard 1984 quantum key distribution protocol in the presence of high loss: A legitimate user intentionally and randomly replaces signal pulses by multiphoton pulses (decoy pulses). Then they check the loss of the decoy pulses. If the loss of the decoy pulses is abnormally less than that of signal pulses, the whole protocol is aborted. Otherwise, to continue the protocol, they estimate the loss of signal multiphoton pulses based on that of decoy pulses. This estimation can be done with an assumption that the two losses have similar values. We justify that assumption.

  16. Characteristics and trends on global environmental monitoring research: a bibliometric analysis based on Science Citation Index Expanded.

    Science.gov (United States)

    Zhang, Di; Fu, Hui-Zhen; Ho, Yuh-Shan

    2017-11-01

    A bibliometric analysis based on the Science Citation Index Expanded from Web of Science was carried out to provide insights into research activities and trends of the environmental monitoring from 1993 to 2012. Study emphases covered publication outputs, language, categories, journals, countries/territories, institutions, words, and hot issues. The results indicated that the annual output of environmental monitoring publications increased steadily. The environmental sciences and analytical chemistry were the two most common categories. Environmental Monitoring and Assessment published the most articles. The USA and the UK ranked in the top two in terms of all five indicators. The U.S. Environmental Protection Agency took the leading position of the institutions in terms of publication output. The synthesized analysis by words in title, author keywords, and KeyWords Plus provided important clues for hot issues. Researchers paid more attention on water environment monitoring than other environmental factors. The contaminants including organic contaminants, heavy metal, and radiation were most common research focuses, and the organic contaminants and heavy metal of the degree of concern were gradually rising. Sensor and biosensor played an important role in the field of environmental monitoring devices. In addition to conventional device detection method, the remote sensing, GIS, and wireless sensor networks were the mainstream environmental monitoring methods. The international organization, social awareness, and the countries' positive and effective political and policies promoted the published articles.

  17. Global analyses of endonucleolytic cleavage in mammals reveal expanded repertoires of cleavage-inducing small RNAs and their targets.

    Science.gov (United States)

    Cass, Ashley A; Bahn, Jae Hoon; Lee, Jae-Hyung; Greer, Christopher; Lin, Xianzhi; Kim, Yong; Hsiao, Yun-Hua Esther; Xiao, Xinshu

    2016-04-20

    In mammals, small RNAs are important players in post-transcriptional gene regulation. While their roles in mRNA destabilization and translational repression are well appreciated, their involvement in endonucleolytic cleavage of target RNAs is poorly understood. Very few microRNAs are known to guide RNA cleavage. Endogenous small interfering RNAs are expected to induce target cleavage, but their target genes remain largely unknown. We report a systematic study of small RNA-mediated endonucleolytic cleavage in mouse through integrative analysis of small RNA and degradome sequencing data without imposing any bias toward known small RNAs. Hundreds of small cleavage-inducing RNAs and their cognate target genes were identified, significantly expanding the repertoire of known small RNA-guided cleavage events. Strikingly, both small RNAs and their target sites demonstrated significant overlap with retrotransposons, providing evidence for the long-standing speculation that retrotransposable elements in mRNAs are leveraged as signals for gene targeting. Furthermore, our analysis showed that the RNA cleavage pathway is also present in human cells but affecting a different repertoire of retrotransposons. These results show that small RNA-guided cleavage is more widespread than previously appreciated. Their impact on retrotransposons in non-coding regions shed light on important aspects of mammalian gene regulation. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  18. Web-based surveillance and global Salmonella distribution, 2000-2002

    DEFF Research Database (Denmark)

    Galanis, E.; Wong, Danilo Lo Fo; Patrick, M.E.

    2006-01-01

    serotypes to a Web-based country databank. We describe the global distribution of reported Salmonella serotypes from human and nonhuman sources from 2000 to 2002. Among human isolates, Salmonella enterica serovar Enteritidis was the most common serotype, accounting for 65% of all isolates. Among nonhuman......Salmonellae are a common cause of foodborne disease worldwide. The World Health Organization (WHO) supports international foodborne disease surveillance through WHO Global Salm-Surv and other activities. WHO Global Salm-Surv members annually report the 15 most frequently isolated Salmonella...... professionals to explore hypotheses related to the sources and distribution of salmonellae worldwide....

  19. Using citizen science data to model the distributions of common songbirds of Turkey under different global climatic change scenarios.

    Science.gov (United States)

    Abolafya, Moris; Onmuş, Ortaç; Şekercioğlu, Çağan H; Bilgin, Raşit

    2013-01-01

    In this study, we evaluated the potential impact of climate change on the distributions of Turkey's songbirds in the 21st century by modelling future distributions of 20 resident and nine migratory species under two global climate change scenarios. We combined verified data from an ornithological citizen science initiative (www.kusbank.org) with maximum entropy modeling and eight bioclimatic variables to estimate species distributions and projections for future time periods. Model predictions for resident and migratory species showed high variability, with some species projected to lose and others projected to gain suitable habitat. Our study helps improve the understanding of the current and potential future distributions of Turkey's songbirds and their responses to climate change, highlights effective strategies to maximize avian conservation efforts in the study region, and provides a model for using citizen science data for biodiversity research in a large developing country with few professional field biologists. Our results demonstrate that climate change will not affect every species equally in Turkey. Expected range reductions in some breeding species will increase the risk of local extinction, whereas others are likely to expand their ranges.

  20. Distribution models for Panicum virgatum (Poaceae) reveal an expanded range in present and future climate regimes in the northeastern United States.

    Science.gov (United States)

    Ahrens, Collin W; Meyer, Thomas H; Auer, Carol A

    2014-11-01

    Expanded area cultivated with the bioenergy crop Panicum virgatum (switchgrass) could alter the genetics of native populations through gene flow, so understanding current and future species distribution is a first step toward estimating ecological impacts. We surveyed switchgrass distribution in the northeastern United States and generated statistical models to address hypotheses about current distribution relative to historical records and responses to climate change. Surveys were conducted on 1600 km of road verges along environmental gradients. Switchgrass abundance became the training data for two multivariate generalized linear models that generated maps representing the probability of switchgrass in road verges. Models were evaluated and the superior model was used with variables from three climate change scenarios for 2050 and 2099. Switchgrass populations were found in 41% of roadside plots and up to 188 km from the coast. The environmental variables temperature, urban areas, and sandy soils were positively correlated with switchgrass presence, while elevation, soil pH, and distance to the coast were negatively correlated. The model without spatial autocorrelation performed better. Models and maps incorporating climate change predictions showed a sharp northward shift in suitable habitat. Switchgrass populations in the northeastern United States occur on inland road verges, supporting the idea that species distribution has expanded relative to historical descriptions of a restricted coastal habitat. The optimal model showed that mean temperature, elevation, and urban development were important in switchgrass distribution today, and climate change will increase suitable habitat for future bioenergy production and wild populations. © 2014 Botanical Society of America, Inc.

  1. A~simple model for predicting the global distribution of the N2 fixing host genus Alnus Mill.: impact of climate change on the global distribution in 2100

    Science.gov (United States)

    Sakalli, A.

    2013-08-01

    The importance of N2-fixing plants has increased in last decades. Alnus (alder) is an important plant group because of its nitrogen fixation ability. Alders are generally distributed in humid locations of boreal, temperate and tropical climate zones, where the nitrogen fixation is an important nitrogen source for other plants. To model the nitrogen fixation by alder, data about the global distribution of alder is absolutely required. In this study a new method and model to predict the distribution of N2-fixing genus on global scale is presented. Three linear functions were defined for the determination of climate area of alder locations. The distribution model was improved with the aid of the soil units from FAO-Unesco Soil Database, and vegetation types from Schmithüsen's biogeographical atlas. The model (Alnus-Distribution-Model, ADM) was also developed to predict the impact of climate change on alder distribution by using climate data of five relevant climate models (PCM, ECHam4, HadCM3, CSIRO2 and CGCM2), and four IPCC climate scenarios (i.e. A1FI, A2, B1 and B2) in 2100. The model covered basic approaches to understand the climate change effect on plant migration in the future.

  2. Expanding the generation and use of economic and financial data to improve HIV program planning and efficiency: a global perspective.

    Science.gov (United States)

    Holmes, Charles B; Atun, Rifat; Avila, Carlos; Blandford, John M

    2011-08-01

    Cost information is needed at multiple levels of health care systems to inform the public health response to HIV. To date, most attention has been paid to identifying the cost drivers of providing antiretroviral treatment, and these data have driven interventions that have been successful in reducing drug and human resource costs. The need for further cost information, especially for less well-studied areas such as HIV prevention, is particularly acute given global budget constraints and ongoing efforts to extract the greatest possible value from money spent on the response. Cost information can be collected from multiple perspectives and levels of the health care system (site, program, and national levels), and it is critical to choose the appropriate methodology in order to generate the appropriate information for decision-making. Organizations such as United States President's Emergency Plan for AIDS Relief, the Global Fund to Fight AIDS, Tuberculosis, and Malaria, and other organizations are working together to bridge the divide between the fields of economics and HIV program implementation by accelerating the collection of cost data and building further local demand and capacity for their use.

  3. Parallel extinction risk and global distribution of languages and species.

    Science.gov (United States)

    Sutherland, William J

    2003-05-15

    There are global threats to biodiversity with current extinction rates well above background levels. Although less well publicized, numerous human languages have also become extinct, and others are threatened with extinction. However, estimates of the number of threatened languages vary considerably owing to the wide range of criteria used. For example, languages have been classified as threatened if the number of speakers is less than 100, 500, 1,000, 10,000, 20,000 or 100,000 (ref. 3). Here I show, by applying internationally agreed criteria for classifying species extinction risk, that languages are more threatened than birds or mammals. Rare languages are more likely to show evidence of decline than commoner ones. Areas with high language diversity also have high bird and mammal diversity and all three show similar relationships to area, latitude, area of forest and, for languages and birds, maximum altitude. The time of human settlement has little effect on current language diversity. Although similar factors explain the diversity of languages and biodiversity, the factors explaining extinction risk for birds and mammals (high altitude, high human densities and insularity) do not explain the numbers of endangered languages.

  4. Theory and Methodology for Forming Creative Design Teams in a  Globally Distributed and Culturally Diverse Environment

    OpenAIRE

    Park, Yongseok

    2014-01-01

    With increased globalization, Internet connectivity, and competitive economic conditions, global organizations are increasingly recognizing the importance of effective global collaborations. Hence, there is a need to extend the use of psychological teaming strategies for domestic team-formations to also accommodate teams that are globally distributed. Previous research efforts have investigated psychological factors for design creativity and effective global collaboration; however, few have...

  5. Projecting the Global Distribution of the Emerging Amphibian Fungal Pathogen, Batrachochytrium dendrobatidis, Based on IPCC Climate Futures.

    Directory of Open Access Journals (Sweden)

    Gisselle Yang Xie

    Full Text Available Projected changes in climate conditions are emerging as significant risk factors to numerous species, affecting habitat conditions and community interactions. Projections suggest species range shifts in response to climate change modifying environmental suitability and is supported by observational evidence. Both pathogens and their hosts can shift ranges with climate change. We consider how climate change may influence the distribution of the emerging infectious amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd, a pathogen associated with worldwide amphibian population losses. Using an expanded global Bd database and a novel modeling approach, we examined a broad set of climate metrics to model the Bd-climate niche globally and regionally, then project how climate change may influence Bd distributions. Previous research showed that Bd distribution is dependent on climatic variables, in particular temperature. We trained a machine-learning model (random forest with the most comprehensive global compilation of Bd sampling records (~5,000 site-level records, mid-2014 summary, including 13 climatic variables. We projected future Bd environmental suitability under IPCC scenarios. The learning model was trained with combined worldwide data (non-region specific and also separately per region (region-specific. One goal of our study was to estimate of how Bd spatial risks may change under climate change based on the best available data. Our models supported differences in Bd-climate relationships among geographic regions. We projected that Bd ranges will shift into higher latitudes and altitudes due to increased environmental suitability in those regions under predicted climate change. Specifically, our model showed a broad expansion of areas environmentally suitable for establishment of Bd on amphibian hosts in the temperate zones of the Northern Hemisphere. Our projections are useful for the development of monitoring designs in these areas

  6. Projecting the Global Distribution of the Emerging Amphibian Fungal Pathogen, Batrachochytrium dendrobatidis, Based on IPCC Climate Futures.

    Science.gov (United States)

    Xie, Gisselle Yang; Olson, Deanna H; Blaustein, Andrew R

    2016-01-01

    Projected changes in climate conditions are emerging as significant risk factors to numerous species, affecting habitat conditions and community interactions. Projections suggest species range shifts in response to climate change modifying environmental suitability and is supported by observational evidence. Both pathogens and their hosts can shift ranges with climate change. We consider how climate change may influence the distribution of the emerging infectious amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), a pathogen associated with worldwide amphibian population losses. Using an expanded global Bd database and a novel modeling approach, we examined a broad set of climate metrics to model the Bd-climate niche globally and regionally, then project how climate change may influence Bd distributions. Previous research showed that Bd distribution is dependent on climatic variables, in particular temperature. We trained a machine-learning model (random forest) with the most comprehensive global compilation of Bd sampling records (~5,000 site-level records, mid-2014 summary), including 13 climatic variables. We projected future Bd environmental suitability under IPCC scenarios. The learning model was trained with combined worldwide data (non-region specific) and also separately per region (region-specific). One goal of our study was to estimate of how Bd spatial risks may change under climate change based on the best available data. Our models supported differences in Bd-climate relationships among geographic regions. We projected that Bd ranges will shift into higher latitudes and altitudes due to increased environmental suitability in those regions under predicted climate change. Specifically, our model showed a broad expansion of areas environmentally suitable for establishment of Bd on amphibian hosts in the temperate zones of the Northern Hemisphere. Our projections are useful for the development of monitoring designs in these areas, especially for

  7. Classic And "Next Generation" Citizen Science: Expanding Data-gathering And Participant Demographics To Better Document Global Environmental Change.

    Science.gov (United States)

    Haines-Stiles, G.

    2015-12-01

    Long-standing citizen science projects such as Audubon's Christmas Bird Count have generated useful data about species range and population numbers for more than 100 years. Recent IPCC reports and the U.S. National Climate Assessment (NCA) routinely include data about changing ecosystems and enviroments. Today new forms of citizen science are beginning to join such classic examples and broaden the demographics of participants and the kinds of information that can be captured, shared and analyzed. Surfers and scientists are hoping to record near-shore measurements of ocean acidification in Smartfin, through GPS, accelerometers and pH sensors on surfboards. Trout Unlimited is working on "Angler Science", documenting water temperature and stream quality in a changing climate, and using DNA analysis to track invasive species. The West Oakland Environmental Indicators Project is adding community mobilization in the face of sea level rise to its decade-long work on air pollution, particulates and asthma. The National Phenology Network encourages year-long observations using the "-Nature's Notebook" app that extend beyond anything possible using government-funded research alone. Understanding oceans, protecting rivers and identifying long-term patterns can contribute useful data to future NCAs, helping meet the otherwise challenging goal of "continuous assessment." How can we manage what we can't measure, for reasons of limited staff or resources? This presentation will offer one answer: by enlisting more and more citizen scientists--sportsmen and women, hobbyists and outdoor enthusiasts who may not even self identify as "citizen scientists"--pursuing their passions while also contributing valuable GEC data. The presentation will also touch on what kinds of information infrastructure can help assure data quality when traditional citizen science is expanded in these ways.

  8. An end to perinatal HIV: success in the US requires ongoing and innovative efforts that should expand globally.

    Science.gov (United States)

    Burr, Carolyn K; Lampe, Margaret A; Corle, Sharron; Margolin, Frances S; Abresh, Chad; Clark, Jill

    2007-07-01

    The dramatic reduction of perinatally transmitted HIV in the United States has been a striking success story in the HIV epidemic. Routine HIV screening during pregnancy followed by appropriate therapy has been extremely effective. This paper puts forth three strategies needed to maintain these gains and reach the goal of eliminating perinatal HIV: standardize medical interventions and policy changes that support perinatal HIV reduction; institute HIV screening in routine preconception care to identify HIV infection in women before pregnancy; and critically focus attention and resources on primary prevention of HIV infection in women. Healthcare providers should incorporate HIV prevention education and routine screening into women's primary health care. Public health leaders should support and fund prevention strategies directed at young women. Successful approaches that have nearly eliminated perinatal HIV transmission in the United States offer valuable lessons that should be applied to primary HIV prevention for women in the United States and globally.

  9. Distributive justice and global health: a call for a global corporate tax.

    Science.gov (United States)

    Blum, J D

    2007-06-01

    Significant efforts have been directed toward addressing the financial needs of the developing world for assistance with public health and related development problems. Both public and private organizations have made considerable economic contributions to assist with immediate and long term health challenges, and there is growing international support for programs of national debit relief. Still, there is a need for additional resources to combat international health problems, which go beyond largesse. This paper calls for the creation of a legally rooted, global tax as a mechanism for consistent long term funding. Specifically, the paper proposes engagement of the World Trade Organization as a vehicle to sponsor a global tax on multinational corporations who have benefited most from the international trading scheme.

  10. Global distribution of grid connected electrical energy storage systems

    Directory of Open Access Journals (Sweden)

    Katja Buss

    2016-06-01

    Full Text Available This article gives an overview of grid connected electrical energy storage systems worldwide, based on public available data. Technologies considered in this study are pumped hydroelectric energy storage (PHES, compressed air energy storage (CAES, sodium-sulfur batteries (NaS, lead-acid batteries, redox-flow batteries, nickel-cadmium batteries (NiCd and lithium-ion batteries. As the research indicates, the worldwide installed capacity of grid connected electrical energy storage systems is approximately 154 GW. This corresponds to a share of 5.5 % of the worldwide installed generation capacity. Furthermore, the article gives an overview of the historical development of installed and used storage systems worldwide. Subsequently, the focus is on each considered technology concerning the current storage size, number of plants and location. In summary it can be stated, PHES is the most commonly used technology worldwide, whereas electrochemical technologies are increasingly gaining in importance. Regarding the distribution of grid connected storage systems reveals the share of installed storage capacity is in Europe and Eastern Asia twice as high as in North America.

  11. The geographical distribution of leadership in globalized clinical trials.

    Directory of Open Access Journals (Sweden)

    Jarno Hoekman

    manuscript writing is modest. This division of labor has significant implications for the scientific and ethical integrity of global clinical research.

  12. Mars Global Digital Dune Database (MGD3): Global dune distribution and wind pattern observations

    Science.gov (United States)

    Hayward, Rosalyn K.; Fenton, Lori; Titus, Timothy N.

    2014-01-01

    The Mars Global Digital Dune Database (MGD3) is complete and now extends from 90°N to 90°S latitude. The recently released south pole (SP) portion (MC-30) of MGD3 adds ∼60,000 km2 of medium to large-size dark dune fields and ∼15,000 km2 of sand deposits and smaller dune fields to the previously released equatorial (EQ, ∼70,000 km2), and north pole (NP, ∼845,000 km2) portions of the database, bringing the global total to ∼975,000 km2. Nearly all NP dunes are part of large sand seas, while the majority of EQ and SP dune fields are individual dune fields located in craters. Despite the differences between Mars and Earth, their dune and dune field morphologies are strikingly similar. Bullseye dune fields, named for their concentric ring pattern, are the exception, possibly owing their distinctive appearance to winds that are unique to the crater environment. Ground-based wind directions are derived from slipface (SF) orientation and dune centroid azimuth (DCA), a measure of the relative location of a dune field inside a crater. SF and DCA often preserve evidence of different wind directions, suggesting the importance of local, topographically influenced winds. In general however, ground-based wind directions are broadly consistent with expected global patterns, such as polar easterlies. Intriguingly, between 40°S and 80°S latitude both SF and DCA preserve their strongest, though different, dominant wind direction, with transport toward the west and east for SF-derived winds and toward the north and west for DCA-derived winds.

  13. Expanded partnerships between medical faculty and medical students: Developing a Global Health curriculum as an example of 'student-led learning' at the University of Queensland, Australia.

    Science.gov (United States)

    Merridew, Nancy; Wilkinson, David

    2010-01-01

    Reflecting trends in medical education from didactic teaching to student-centred learning, the novel approach of student-led learning was applied at the University of Queensland (UQ) School of Medicine. This article examines the benefits, risks and limitations of curriculum development led by students. The Project aimed to trial student-led development of a Global Health curriculum module for the UQ medical programme, as part of an international collaboration with related Health Sciences activities of Universitas 21 (U21). The Head (Dean) of the UQ School of Medicine instigated the Project. A student Convenor was appointed to lead it and, in conjunction with faculty, to design curriculum Learning Objectives and supporting resources. The initial vision of the Project was greatly expanded, from an optional elective to a compulsory curriculum module with inbuilt prospective outcome measures. The module was established in less than 12 months and is now being delivered throughout the 4-year medical programme. A process for ongoing student leadership of the Project was established. Student-led learning can be effective if given adequate support by faculty. The UQ School of Medicine's new curriculum module and collaboration with U21 promote the teaching of Global Health.

  14. Mapping the spatial distribution of global anthropogenic mercury atmospheric emission inventories

    Science.gov (United States)

    Wilson, Simon J.; Steenhuisen, Frits; Pacyna, Jozef M.; Pacyna, Elisabeth G.

    This paper describes the procedures employed to spatially distribute global inventories of anthropogenic emissions of mercury to the atmosphere, prepared by Pacyna, E.G., Pacyna, J.M., Steenhuisen, F., Wilson, S. [2006. Global anthropogenic mercury emission inventory for 2000. Atmospheric Environment, this issue, doi:10.1016/j.atmosenv.2006.03.041], and briefly discusses the results of this work. A new spatially distributed global emission inventory for the (nominal) year 2000, and a revised version of the 1995 inventory are presented. Emissions estimates for total mercury and major species groups are distributed within latitude/longitude-based grids with a resolution of 1×1 and 0.5×0.5°. A key component in the spatial distribution procedure is the use of population distribution as a surrogate parameter to distribute emissions from sources that cannot be accurately geographically located. In this connection, new gridded population datasets were prepared, based on the CEISIN GPW3 datasets (CIESIN, 2004. Gridded Population of the World (GPW), Version 3. Center for International Earth Science Information Network (CIESIN), Columbia University and Centro Internacional de Agricultura Tropical (CIAT). GPW3 data are available at http://beta.sedac.ciesin.columbia.edu/gpw/index.jsp). The spatially distributed emissions inventories and population datasets prepared in the course of this work are available on the Internet at www.amap.no/Resources/HgEmissions/

  15. The Global Inventor Gap: Distribution and Equality of World-Wide Inventive Effort, 1990–2010

    Science.gov (United States)

    Toivanen, Hannes; Suominen, Arho

    2015-01-01

    Applying distance-to-frontier analysis, we have used 2.9 million patents and population data to assess whether the relative capacity of world countries and major regions to create new knowledge and technology has become globally more equal or less equal between 1990 and 2010. We show with the Gini coefficient that the global distribution of inventors has become more equal between major countries and regions. However, this trend has been largely due to the improved performance of only two major countries, China and India. The worst performing regions, totalling a population of almost 2 billion, are actually falling behind. Our results suggest that substantial parts of the global population have fallen further behind countries at the global frontier in their ability to create new knowledge and inventions, and that the catch-up among the least developed and middle-income countries is highly uneven, prompting questions about the nature and future of the global knowledge economy. PMID:25849202

  16. The global inventor gap: distribution and equality of world-wide inventive effort, 1990-2010.

    Directory of Open Access Journals (Sweden)

    Hannes Toivanen

    Full Text Available Applying distance-to-frontier analysis, we have used 2.9 million patents and population data to assess whether the relative capacity of world countries and major regions to create new knowledge and technology has become globally more equal or less equal between 1990 and 2010. We show with the Gini coefficient that the global distribution of inventors has become more equal between major countries and regions. However, this trend has been largely due to the improved performance of only two major countries, China and India. The worst performing regions, totalling a population of almost 2 billion, are actually falling behind. Our results suggest that substantial parts of the global population have fallen further behind countries at the global frontier in their ability to create new knowledge and inventions, and that the catch-up among the least developed and middle-income countries is highly uneven, prompting questions about the nature and future of the global knowledge economy.

  17. The global inventor gap: distribution and equality of world-wide inventive effort, 1990-2010.

    Science.gov (United States)

    Toivanen, Hannes; Suominen, Arho

    2015-01-01

    Applying distance-to-frontier analysis, we have used 2.9 million patents and population data to assess whether the relative capacity of world countries and major regions to create new knowledge and technology has become globally more equal or less equal between 1990 and 2010. We show with the Gini coefficient that the global distribution of inventors has become more equal between major countries and regions. However, this trend has been largely due to the improved performance of only two major countries, China and India. The worst performing regions, totalling a population of almost 2 billion, are actually falling behind. Our results suggest that substantial parts of the global population have fallen further behind countries at the global frontier in their ability to create new knowledge and inventions, and that the catch-up among the least developed and middle-income countries is highly uneven, prompting questions about the nature and future of the global knowledge economy.

  18. Global Software and IT A Guide to Distributed Development, Projects, and Outsourcing

    CERN Document Server

    Ebert, Christof

    2011-01-01

    Global software engineering, implying both internal and outsourced development, is a fast-growing scenario within industry; the growth rates in some sectors are more than 20% per year. However, half of all offshoring activities are cancelled within the first 2 years, at tremendous unanticipated cost to the organization.   This book will provide a more balanced framework for planning global development, covering topics such as managing people in distributed sites, managing a project across locations, mitigating the risk of offshoring, processes for global development, practical outsourcin

  19. Orchestration of Globally Distributed Knowledge within MNC Network: A Collaborative-oriented View

    DEFF Research Database (Denmark)

    Sajadirad, Solmaz; Lassen, Astrid Heidemann; Søberg, Peder Veng

    2017-01-01

    -firm objects and the characteristics of knowledge orchestration processes. To this end, a conceptual framework is applied to eleven case studies from Danish industries. The findings suggest that adopting a collaborative-oriented view of the use of inter-firm objects facilitates orchestration of globally...... of headquarters’ control over knowledge flow and subsidiaries’ operation. Additionally, our findings propose that different approaches to knowledge orchestration can result in different degrees of innovation performance. This study extends existing literature on global knowledge management by focusing exclusively...... and effectiveness of globally distributed network....

  20. Tropospheric Ozone Assessment Report: Assessment of global-scale model performance for global and regional ozone distributions, variability, and trends

    Directory of Open Access Journals (Sweden)

    P. J. Young

    2018-01-01

    Full Text Available The goal of the Tropospheric Ozone Assessment Report (TOAR is to provide the research community with an up-to-date scientific assessment of tropospheric ozone, from the surface to the tropopause. While a suite of observations provides significant information on the spatial and temporal distribution of tropospheric ozone, observational gaps make it necessary to use global atmospheric chemistry models to synthesize our understanding of the processes and variables that control tropospheric ozone abundance and its variability. Models facilitate the interpretation of the observations and allow us to make projections of future tropospheric ozone and trace gas distributions for different anthropogenic or natural perturbations. This paper assesses the skill of current-generation global atmospheric chemistry models in simulating the observed present-day tropospheric ozone distribution, variability, and trends. Drawing upon the results of recent international multi-model intercomparisons and using a range of model evaluation techniques, we demonstrate that global chemistry models are broadly skillful in capturing the spatio-temporal variations of tropospheric ozone over the seasonal cycle, for extreme pollution episodes, and changes over interannual to decadal periods. However, models are consistently biased high in the northern hemisphere and biased low in the southern hemisphere, throughout the depth of the troposphere, and are unable to replicate particular metrics that define the longer term trends in tropospheric ozone as derived from some background sites. When the models compare unfavorably against observations, we discuss the potential causes of model biases and propose directions for future developments, including improved evaluations that may be able to better diagnose the root cause of the model-observation disparity. Overall, model results should be approached critically, including determining whether the model performance is acceptable for

  1. On the duality of globally constrained separable problems and its application to distributed signal processing

    NARCIS (Netherlands)

    Sherson, T.W.; Heusdens, R.; Kleijn, W.B.

    2016-01-01

    In this paper, we focus on the challenge of processing data generated within decentralised wireless sensor networks in a distributed manner. When the desired operations can be expressed as globally constrained separable convex optimisation problems, we show how we can convert these to extended

  2. Unbiased global determination of parton distributions and their uncertainties at NNLO and at LO

    NARCIS (Netherlands)

    Collaboration, The NNPDF; Ball, Richard D.; Bertone, Valerio; Cerutti, Francesco; Debbio, Luigi Del; Forte, Stefano; Guffanti, Alberto; Latorre, Jose I.; Rojo, Juan; Ubiali, Maria

    2012-01-01

    We present a determination of the parton distributions of the nucleon from a global set of hard scattering data using the NNPDF methodology at LO and NNLO in perturbative QCD, thereby generalizing to these orders the NNPDF2.1 NLO parton set. Heavy quark masses are included using the so-called FONLL

  3. Modeling the UT effect in global distribution of ionospheric electric fields

    DEFF Research Database (Denmark)

    Lukianova, R.; Christiansen, Freddy

    2008-01-01

    A new approach for modeling the global distribution of ionospheric electric potentials utilizing high-precision maps of field-aligned currents (FACs) derived from measurements by the Orsted and Magsat satellites as input to a comprehensive numerical scheme is presented. We simulate the universal ...

  4. Supporting Trust in Globally Distributed Software Teams: The Impact of Visualized Collaborative Traces on Perceived Trustworthiness

    Science.gov (United States)

    Trainer, Erik Harrison

    2012-01-01

    Trust plays an important role in collaborations because it creates an environment in which people can openly exchange ideas and information with one another and engineer innovative solutions together with less perceived risk. The rise in globally distributed software development has created an environment in which workers are likely to have less…

  5. Estimating distributions of health state severity for the global burden of disease study

    NARCIS (Netherlands)

    D. Burstein (David); T.D. Fleming (Thomas D); J.A. Haagsma (Juanita); J.A. Salomon (Joshua A); T. Vos (Theo); C.J.L. Murray (Christopher)

    2015-01-01

    textabstractBackground: Many major causes of disability in the Global Burden of Disease (GBD) study present with a range of severity, and for most causes finding population distributions of severity can be difficult due to issues of sparse data, inconsistent measurement, and need to account for

  6. A first unbiased global NLO determination of parton distributions and their uncertainties

    NARCIS (Netherlands)

    Ball, Richard D.; Debbio, Luigi Del; Forte, Stefano; Guffanti, Alberto; Latorre, Jose I.; Rojo, Juan; Ubiali, Maria

    2010-01-01

    We present a determination of the parton distributions of the nucleon from a global set of hard scattering data using the NNPDF methodology: NNPDF2.0. Experimental data include deep-inelastic scattering with the combined HERA-I dataset, fixed target Drell-Yan production, collider weak boson

  7. The global distribution of the arbovirus vectors Aedes aegypti and Ae. albopictus

    Science.gov (United States)

    Kraemer, Moritz UG; Sinka, Marianne E; Duda, Kirsten A; Mylne, Adrian QN; Shearer, Freya M; Barker, Christopher M; Moore, Chester G; Carvalho, Roberta G; Coelho, Giovanini E; Van Bortel, Wim; Hendrickx, Guy; Schaffner, Francis; Elyazar, Iqbal RF; Teng, Hwa-Jen; Brady, Oliver J; Messina, Jane P; Pigott, David M; Scott, Thomas W; Smith, David L; Wint, GR William; Golding, Nick; Hay, Simon I

    2015-01-01

    Dengue and chikungunya are increasing global public health concerns due to their rapid geographical spread and increasing disease burden. Knowledge of the contemporary distribution of their shared vectors, Aedes aegypti and Aedes albopictus remains incomplete and is complicated by an ongoing range expansion fuelled by increased global trade and travel. Mapping the global distribution of these vectors and the geographical determinants of their ranges is essential for public health planning. Here we compile the largest contemporary database for both species and pair it with relevant environmental variables predicting their global distribution. We show Aedes distributions to be the widest ever recorded; now extensive in all continents, including North America and Europe. These maps will help define the spatial limits of current autochthonous transmission of dengue and chikungunya viruses. It is only with this kind of rigorous entomological baseline that we can hope to project future health impacts of these viruses. DOI: http://dx.doi.org/10.7554/eLife.08347.001 PMID:26126267

  8. Longitudinal observations of globally distributed design teams: The impacts on Product Development

    DEFF Research Database (Denmark)

    Taylor, Thomas Paul; Ahmed-Kristensen, Saeema

    2015-01-01

    the success of a globally distributed PD project are mapped across the phases of PD, beginning from the early planning phase and development through to the final testing and refinement. Furthermore, the relationship between the impact factors (IF’s) and key parameters for performance is described....

  9. FORMATION OF DISTRIBUTION SYSTEMS WITH THE INVOLVEMENT OF THE GLOBAL RETAIL CHAINS

    Directory of Open Access Journals (Sweden)

    L. Kudyrko

    2015-08-01

    Full Text Available The purpose of the article is to analyze the features of formation and functioning of multi-marketing distribution systems involving global retail chains and identify the causes of conflicts between participants in the global supply chain and suggest possible ways to displace them. The article represents the author’s definition of the term “global retail chain”. The role and responsibilities of international retailers in the formation of marketing structures on international markets are discovered. The algorithm of the relationship between the participants in the traditional vertical marketing system with the definition of international components is determined. The conflict causes between the participants within the distribution channel are identified.

  10. The Tara Oceans voyage reveals global diversity and distribution patterns of marine planktonic ciliates

    Science.gov (United States)

    Gimmler, Anna; Korn, Ralf; de Vargas, Colomban; Audic, Stéphane; Stoeck, Thorsten

    2016-01-01

    Illumina reads of the SSU-rDNA-V9 region obtained from the circumglobal Tara Oceans expedition allow the investigation of protistan plankton diversity patterns on a global scale. We analyzed 6,137,350 V9-amplicons from ocean surface waters and the deep chlorophyll maximum, which were taxonomically assigned to the phylum Ciliophora. For open ocean samples global planktonic ciliate diversity is relatively low (ca. 1,300 observed and predicted ciliate OTUs). We found that 17% of all detected ciliate OTUs occurred in all oceanic regions under study. On average, local ciliate OTU richness represented 27% of the global ciliate OTU richness, indicating that a large proportion of ciliates is widely distributed. Yet, more than half of these OTUs shared oceanic carbonate system and temperature. Planktonic ciliates displayed distinct vertical distributions relative to chlorophyll a. In contrast, the Tara Oceans dataset did not reveal any evidence that latitude is structuring ciliate communities. PMID:27633177

  11. Atmospheric Test Models and Numerical Experiments for the Simulation of the Global Distributions of Weather Data Transponders III. Horizontal Distributions

    Energy Technology Data Exchange (ETDEWEB)

    Molenkamp, C.R.; Grossman, A.

    1999-12-20

    A network of small balloon-borne transponders which gather very high resolution wind and temperature data for use by modern numerical weather predication models has been proposed to improve the reliability of long-range weather forecasts. The global distribution of an array of such transponders is simulated using LLNL's atmospheric parcel transport model (GRANTOUR) with winds supplied by two different general circulation models. An initial study used winds from CCM3 with a horizontal resolution of about 3 degrees in latitude and longitude, and a second study used winds from NOGAPS with a 0.75 degree horizontal resolution. Results from both simulations show that reasonable global coverage can be attained by releasing balloons from an appropriate set of launch sites.

  12. Spatial and temporal distributions of hexabromocyclododecanes in the vicinity of an expanded polystyrene material manufacturing plant in Tianjin, China.

    Science.gov (United States)

    Zhu, Hongkai; Zhang, Kai; Sun, Hongwen; Wang, Fei; Yao, Yiming

    2017-03-01

    To investigate the environmental fate of 3 main hexabromocyclododecane diastereoisomers (α-, β-, and γ-HBCDs), samples from various environmental media, including outdoor settled dust, soil, sediment, plant tissues (holly, cypress and pine) and marine species (shrimp, crab and fish) were obtained around an expanded polystyrene material manufacturing plant in Tianjin, China. The 3 main HBCD diastereoisomers were detected with the total concentrations ranging from 328 to 31,752 ng/g dry weight (dw), 2.91-1730 ng/g dw, 23.5-716 ng/g dw, 3.45-2494 ng/g dw, and 0.878-44.8 ng/g dw in the dust, soil, sediment, plant tissues, and marine species, respectively. This indicated that a point source of HBCDs could bring wide impact on its vicinal environment. A significant increasing trend of HBCDs concentrations was noted, as indicated by 12.9-41.6% of increasing rates in total concentrations of HBCDs at four sediment sites in the past five years. The diastereoisomer profiles were sorted into 3 groups: dust, soil and sediment, which had no statistical difference from commercial EPS-products (p > 0.05); plant tissues, which showed a moderate increase of α-isomer (22.9 ± 3.3%); and marine species, which were dominated by α-isomer (62.6 ± 2.8%). For α- and β-isomers, the results of enantiomeric analysis showed a preferential accumulation of the (+)-enantiomer in part of plant tissues and all marine organisms (p  0.05). Besides, marine food web magnification is observed for HBCDs, with trophic magnification factors close to 2. The daily intakes of HBCDs were estimated to be 0.058-5.84 ng/kg-bw/day for local residents through dust and soil ingestion and 0.048-8.43 ng/kg-bw/day for Tianjin citizens through seafood consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Aging transition in systems of oscillators with global distributed-delay coupling

    Science.gov (United States)

    Rahman, B.; Blyuss, K. B.; Kyrychko, Y. N.

    2017-09-01

    We consider a globally coupled network of active (oscillatory) and inactive (nonoscillatory) oscillators with distributed-delay coupling. Conditions for aging transition, associated with suppression of oscillations, are derived for uniform and gamma delay distributions in terms of coupling parameters and the proportion of inactive oscillators. The results suggest that for the uniform distribution increasing the width of distribution for the same mean delay allows aging transition to happen for a smaller coupling strength and a smaller proportion of inactive elements. For gamma distribution with sufficiently large mean time delay, it may be possible to achieve aging transition for an arbitrary proportion of inactive oscillators, as long as the coupling strength lies in a certain range.

  14. Global distribution of clay-size minerals on land surface for biogeochemical and climatological studies

    Science.gov (United States)

    Ito, Akihiko; Wagai, Rota

    2017-08-01

    Clay-size minerals play important roles in terrestrial biogeochemistry and atmospheric physics, but their data have been only partially compiled at global scale. We present a global dataset of clay-size minerals in the topsoil and subsoil at different spatial resolutions. The data of soil clay and its mineralogical composition were gathered through a literature survey and aggregated by soil orders of the Soil Taxonomy for each of the ten groups: gibbsite, kaolinite, illite/mica, smectite, vermiculite, chlorite, iron oxide, quartz, non-crystalline, and others. Using a global soil map, a global dataset of soil clay-size mineral distribution was developed at resolutions of 2' to 2° grid cells. The data uncertainty associated with data variability and assumption was evaluated using a Monte Carlo method, and validity of the clay-size mineral distribution obtained in this study was examined by comparing with other datasets. The global soil clay data offer spatially explicit studies on terrestrial biogeochemical cycles, dust emission to the atmosphere, and other interdisciplinary earth sciences.

  15. Highly resolved global distribution of tropospheric NO2 using GOME narrow swath mode data

    Directory of Open Access Journals (Sweden)

    S. Beirle

    2004-01-01

    Full Text Available The Global Ozone Monitoring Experiment (GOME allows the retrieval of tropospheric vertical column densities (VCDs of NO2 on a global scale. Regions with enhanced industrial activity can clearly be detected, but the standard spatial resolution of the GOME ground pixels (320x40km2 is insufficient to resolve regional trace gas distributions or individual cities. Every 10 days within the nominal GOME operation, measurements are executed in the so called narrow swath mode with a much better spatial resolution (80x40km2. We use this data (1997-2001 to construct a detailed picture of the mean global tropospheric NO2 distribution. Since - due to the narrow swath - the global coverage of the high resolution observations is rather poor, it has proved to be essential to deseasonalize the single narrow swath mode observations to retrieve adequate mean maps. This is done by using the GOME backscan information. The retrieved high resolution map illustrates the shortcomings of the standard size GOME pixels and reveals an unprecedented wealth of details in the global distribution of tropospheric NO2. Localised spots of enhanced NO2 VCD can be directly associated to cities, heavy industry centers and even large power plants. Thus our result helps to check emission inventories. The small spatial extent of NO2 'hot spots' allows us to estimate an upper limit of the mean lifetime of boundary layer NOx of 17h on a global scale. The long time series of GOME data allows a quantitative comparison of the narrow swath mode data to the nominal resolution. Thus we can analyse the dependency of NO2 VCDs on pixel size. This is important for comparing GOME data to results of new satellite instruments like SCIAMACHY (launched March 2002 on ENVISAT, OMI (launched July 2004 on AURA or GOME II (to be launched 2005 with an improved spatial resolution.

  16. Phosphorus in agricultural soils: drivers of its distribution at the global scale.

    Science.gov (United States)

    Ringeval, Bruno; Augusto, Laurent; Monod, Hervé; van Apeldoorn, Dirk; Bouwman, Lex; Yang, Xiaojuan; Achat, David L; Chini, Louise P; Van Oost, Kristof; Guenet, Bertrand; Wang, Rong; Decharme, Bertrand; Nesme, Thomas; Pellerin, Sylvain

    2017-08-01

    Phosphorus (P) availability in soils limits crop yields in many regions of the World, while excess of soil P triggers aquatic eutrophication in other regions. Numerous processes drive the global spatial distribution of P in agricultural soils, but their relative roles remain unclear. Here, we combined several global data sets describing these drivers with a soil P dynamics model to simulate the distribution of P in agricultural soils and to assess the contributions of the different drivers at the global scale. We analysed both the labile inorganic P (P ILAB ), a proxy of the pool involved in plant nutrition and the total soil P (P TOT ). We found that the soil biogeochemical background corresponding to P inherited from natural soils at the conversion to agriculture (BIOG) and farming practices (FARM) were the main drivers of the spatial variability in cropland soil P content but that their contribution varied between P TOT vs. P ILAB . When the spatial variability was computed between grid cells at half-degree resolution, we found that almost all of the P TOT spatial variability could be explained by BIOG, while BIOG and FARM explained 38% and 63% of P ILAB spatial variability, respectively. Our work also showed that the driver contribution was sensitive to the spatial scale characterizing the variability (grid cell vs. continent) and to the region of interest (global vs. tropics for instance). In particular, the heterogeneity of farming practices between continents was large enough to make FARM contribute to the variability in P TOT at that scale. We thus demonstrated how the different drivers were combined to explain the global distribution of agricultural soil P. Our study is also a promising approach to investigate the potential effect of P as a limiting factor for agroecosystems at the global scale. © 2017 John Wiley & Sons Ltd.

  17. Global Distribution of Extreme Precipitation and High-Impact Landslides in 2010 Relative to Previous Years

    Science.gov (United States)

    Kirschbaum, Dalia; Adler, Robert; Adler, David; Peters-Lidard, Christa; Huffman, George

    2012-01-01

    It is well known that extreme or prolonged rainfall is the dominant trigger of landslides worldwide. While research has evaluated the spatiotemporal distribution of extreme rainfall and landslides at local or regional scales using in situ data, few studies have mapped rainfall-triggered landslide distribution globally due to the dearth of landslide data and consistent precipitation information. This study uses a newly developed Global Landslide Catalog (GLC) and a 13-year satellite-based precipitation record from TRMM data. For the first time, these two unique products provide the foundation to quantitatively evaluate the co-occurrence of precipitation and landslides globally. Evaluation of the GLC indicates that 2010 had a large number of high-impact landslide events relative to previous years. This study considers how variations in extreme and prolonged satellite-based rainfall are related to the distribution of landslides over the same time scales for three active landslide areas: Central America, the Himalayan Arc, and central-eastern China. Several test statistics confirm that TRMM rainfall generally scales with the observed increase in landslide reports and fatal events for 2010 and previous years over each region. These findings suggest that the co-occurrence of satellite precipitation and landslide reports may serve as a valuable indicator for characterizing the spatiotemporal distribution of landslide-prone areas in order to establish a global rainfall-triggered landslide climatology. This study characterizes the variability of satellite precipitation data and reported landslide activity at the globally scale in order to improve landslide cataloging, forecasting and quantify potential triggering sources at daily, monthly and yearly time scales.

  18. The global avian invasions atlas, a database of alien bird distributions worldwide.

    Science.gov (United States)

    Dyer, Ellie E; Redding, David W; Blackburn, Tim M

    2017-03-28

    The introduction of species to locations where they do not naturally occur (termed aliens) can have far-reaching and unpredictable environmental and economic consequences. Therefore there is a strong incentive to stem the tide of alien species introduction and spread. In order to identify broad patterns and processes of alien invasions, a spatially referenced, global dataset on the historical introductions and alien distributions of a complete taxonomic group is required. Here we present the Global Avian Invasions Atlas (GAVIA)-a new spatial and temporal dataset comprising 27,723 distribution records for 971 alien bird species introduced to 230 countries and administrative areas spanning the period 6000BCE-AD2014. GAVIA was initiated to provide a unified database of records on alien bird introductions, incorporating records from all stages of invasion, including introductions that have failed as well as those that have succeeded. GAVIA represents the most comprehensive resource on the global distribution of alien species in any major taxon, allowing the spatial and temporal dynamics of alien bird distributions to be examined.

  19. Climate change and the potential global distribution of Aedes aegypti: spatial modelling using GIS and CLIMEX.

    Science.gov (United States)

    Khormi, Hassan M; Kumar, Lalit

    2014-05-01

    We examined the potential added risk posed by global climate change on the dengue vector Aedes aegypti abundance using CLIMEX, a powerful tool for exploring the relationship between the fundamental and realised niche of any species. After calibrating the model using data from several knowledge domains, including geographical distribution records, we estimated potential distributions of the mosquito under current and future potential scenarios. The impact of climate change on its potential distribution was assessed with two global climate models, the CSIRO-Mk3.0 and the MIROC-H, run with two potential, future emission scenarios (A1B and A2) published by the Intergovernmental Panel on Climate Change. We compared today's climate situation with two arbitrarily chosen future time points (2030 and 2070) to see the impact on the worldwide distribution of A. aegypti . The model for the current global climate indicated favourable areas for the mosquito within its known distribution in tropical and subtropical areas. However, even if much of the tropics and subtropics will continue to be suitable, the climatically favourable areas for A. aegypti globally are projected to contract under the future scenarios produced by these models, while currently unfavourable areas, such as inland Australia, the Arabian Peninsula, southern Iran and some parts of North America may become climatically favourable for this mosquito species. The climate models for the Aedes dengue vector presented here should be useful for management purposes as they can be adapted for decision/making regarding allocation of resources for dengue risk toward areas where risk infection remains and away from areas where climatic suitability is likely to decrease in the future.

  20. Global perspectives on ensuring the safety of pharmaceutical products in the distribution process
.

    Science.gov (United States)

    Jeong, Sohyun; Ji, Eunhee

    2018-01-01

    The distribution of counterfeit or falsified drugs is increasing worldwide. This can contribute to the high burden of disease and cost to society and is of global concern with the worldwide circulation of pharmaceuticals. The preparation and implementation of good distribution practice should be one of the most important aspects of ensuring safe drug circulation and administration. This research aimed to compare and analyze good distribution practice guidelines from advanced countries and international organizations, and to evaluate the status of the current good distribution practice guidelines in the world. Advanced pharmaceutical countries and international organizations, such as the World Health Organization, European Union, Pharmaceutical Inspection Co-operation Scheme, United States of America, Canada, and Australia, which have stable good distribution practice guidelines and public confidence, were included in the analysis. The World Health Organization and European Union guidelines are models for standardized good distribution practice for nations worldwide. The United States of America has a combination of four different series of distribution practices which have a unique structure and detailed content compared to those of other countries. The Canadian guidelines focus on temperature control during storage and transportation. The Australian guidelines apply to both classes of medicinal products and medical devices and need separate standardization. Transparent information about the Internet chain, international cooperation regarding counterfeiting, a high-standard qualification of sellers and customers, and technology to track and trace the whole life cycle of drugs should be the main focus of future good distribution practice guidelines worldwide.
.

  1. Distributed embedded controller development with petri nets application to globally-asynchronous locally-synchronous systems

    CERN Document Server

    Moutinho, Filipe de Carvalho

    2016-01-01

    This book describes a model-based development approach for globally-asynchronous locally-synchronous distributed embedded controllers.  This approach uses Petri nets as modeling formalism to create platform and network independent models supporting the use of design automation tools.  To support this development approach, the Petri nets class in use is extended with time-domains and asynchronous-channels. The authors’ approach uses models not only providing a better understanding of the distributed controller and improving the communication among the stakeholders, but also to be ready to support the entire lifecycle, including the simulation, the verification (using model-checking tools), the implementation (relying on automatic code generators), and the deployment of the distributed controller into specific platforms. Uses a graphical and intuitive modeling formalism supported by design automation tools; Enables verification, ensuring that the distributed controller was correctly specified; Provides flex...

  2. Exploring the role of movement in determining the global distribution of marine biomass using a coupled hydrodynamic - Size-based ecosystem model

    Science.gov (United States)

    Watson, James R.; Stock, Charles A.; Sarmiento, Jorge L.

    2015-11-01

    Modeling the dynamics of marine populations at a global scale - from phytoplankton to fish - is necessary if we are to quantify how climate change and other broad-scale anthropogenic actions affect the supply of marine-based food. Here, we estimate the abundance and distribution of fish biomass using a simple size-based food web model coupled to simulations of global ocean physics and biogeochemistry. We focus on the spatial distribution of biomass, identifying highly productive regions - shelf seas, western boundary currents and major upwelling zones. In the absence of fishing, we estimate the total ocean fish biomass to be ∼ 2.84 ×109 tonnes, similar to previous estimates. However, this value is sensitive to the choice of parameters, and further, allowing fish to move had a profound impact on the spatial distribution of fish biomass and the structure of marine communities. In particular, when movement is implemented the viable range of large predators is greatly increased, and stunted biomass spectra characterizing large ocean regions in simulations without movement, are replaced with expanded spectra that include large predators. These results highlight the importance of considering movement in global-scale ecological models.

  3. Expanding subjectivities

    DEFF Research Database (Denmark)

    Lundgaard Andersen, Linda; Soldz, Stephen

    2012-01-01

    A major theme in recent psychoanalytic thinking concerns the use of therapist subjectivity, especially “countertransference,” in understanding patients. This thinking converges with and expands developments in qualitative research regarding the use of researcher subjectivity as a tool to understa...

  4. Expander Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Expander Codes - The Sipser–Spielman Construction. Priti Shankar. General Article Volume 10 ... Author Affiliations. Priti Shankar1. Department of Computer Science and Automation, Indian Institute of Science Bangalore 560 012, India.

  5. Global carbon monoxide vertical distributions from spaceborne high-resolution FTIR nadir measurements

    Directory of Open Access Journals (Sweden)

    B. Barret

    2005-01-01

    Full Text Available This paper presents the first global distributions of CO vertical profiles retrieved from a thermal infrared FTS working in the nadir geometry. It is based on the exploitation of the high resolution and high quality spectra measured by the Interferometric Monitor of Greenhouse gases (IMG which flew onboard the Japanese ADEOS platform in 1996-1997. The retrievals are performed with an algorithm based on the Optimal Estimation Method (OEM and are characterized in terms of vertical sensitivity and error budget. It is found that most of the IMG measurements contain between 1.5 and 2.2 independent pieces of information about the vertical distribution of CO from the lower troposphere to the upper troposphere-lower stratosphere (UTLS. The retrievals are validated against coincident NOAA/CMDL in situ surface measurements and NDSC/FTIR total columns measurements. The retrieved global distributions of CO are also found to be in good agreement with the distributions modeled by the GEOS-CHEM 3D CTM, highlighting the ability of IMG to capture the horizontal as well as the vertical structure of the CO distributions.

  6. Global synchronization of memristive neural networks subject to random disturbances via distributed pinning control.

    Science.gov (United States)

    Guo, Zhenyuan; Yang, Shaofu; Wang, Jun

    2016-12-01

    This paper presents theoretical results on global exponential synchronization of multiple memristive neural networks in the presence of external noise by means of two types of distributed pinning control. The multiple memristive neural networks are coupled in a general structure via a nonlinear function, which consists of a linear diffusive term and a discontinuous sign term. A pinning impulsive control law is introduced in the coupled system to synchronize all neural networks. Sufficient conditions are derived for ascertaining global exponential synchronization in mean square. In addition, a pinning adaptive control law is developed to achieve global exponential synchronization in mean square. Both pinning control laws utilize only partial state information received from the neighborhood of the controlled neural network. Simulation results are presented to substantiate the theoretical results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. First report of brown widow spider sightings in Peninsular Malaysia and notes on its global distribution.

    Science.gov (United States)

    Muslimin, Mustakiza; Wilson, John-James; Ghazali, Amir-Ridhwan M; Braima, Kamil A; Jeffery, John; Wan-Nor, Fitri; Alaa-Eldin, Mohamed E; Mohd-Zin, Siti-Waheeda; Wan-Yusoff, Wan S; Norma-Rashid, Yusoff; Lau, Yee L; Rohela, Mahmud; Abdul-Aziz, Noraishah M

    2015-01-01

    The brown widow spider (Latrodectus geometricus Koch, 1841) has colonised many parts of the world from its continent of origin, Africa. By at least 1841, the species had successfully established populations in South America and has more recently expanded its range to the southern states of North America. This highly adaptable spider has been far more successful in finding its niche around the world than its famous cousins, the black widow, Latrodectus mactans, found in the south-eastern states of North America, and the red-back, Latrodectus hasselti, found mostly in Australia, New Zealand and Japan. We performed an extensive web search of brown widow sightings and mapped the location of each sighting using ArcGIS. Specimens reputedly of the species L. geometricus were collected at three localities in Peninsular Malaysia. The spiders were identified and documented based on an examination of morphological characteristics and DNA barcoding. The spiders found in Peninsular Malaysia were confirmed to be Latrodectus geometricus based on their morphological characteristics and DNA barcodes. We recorded 354 sightings of the brown widow in 58 countries, including Peninsular Malaysia. Reports from the Americas and the Far East suggest a global-wide invasion of the brown widow spider. Herein we report the arrival of the brown widow spider in Peninsular Malaysia and provide notes on the identification of the species and its recently expanded range.

  8. Global carbon monoxide vertical distributions from spaceborne high-resolution FTIR nadir measurements

    OpenAIRE

    B. Barret; Turquety, S.; Hurtmans, D; Clerbaux, C.; Hadji-Lazaro, J.; I. Bey; Auvray, M.; P.-F. Coheur

    2005-01-01

    This paper presents the first global distributions of CO vertical profiles retrieved from a thermal infrared FTS working in the nadir geometry. It is based on the exploitation of the high resolution and high quality spectra measured by the Interferometric Monitor of Greenhouse gases (IMG) which flew onboard the Japanese ADEOS platform in 1996-1997. The retrievals are performed with an algorithm based on the Optimal Estimation Method (OEM) and are characterized in terms of vertical sensitivity...

  9. Spatiotemporal change in geographical distribution of global climate types in the context of climate warming

    Science.gov (United States)

    Zhang, Xianliang; Yan, Xiaodong

    2014-08-01

    After standardizing global land climate gridded data from the Climatic Research Unit TS (time-series) 3.1 dataset for the period 1901-2009, cluster analysis is used to objectively classify world climates into 14 climate types. These climate types establish a baseline classification map and the types are named according to Köppen-Geiger climate classifications. Although the cluster analysis and Köppen classification methods are very different, the distributions of climate types obtained by the two methods are similar. Moreover, the climate types we identify also coincide well with their corresponding vegetation types. Thus, cluster analysis can be used as an effective alternative to the Köppen classification method for classifying world climate types. The spatial and temporal changes in geographical distribution of global climate types were investigated in 25-year intervals, and Cohen's kappa coefficient is used to detect agreement between the periods. Globally, although an obvious trend in increasing global temperature is found, distribution of climate types overall show no distinct changes over the periods. However, at the regional scale, spatial change in distribution of climate types is evident in South America and Africa. In South America, larger areas of the "fully humid equatorial rainforest" (Af) and "equatorial savannah with dry winter" (Aw) climate types have changed types. In Africa, changes mainly occurred in the Af, "equatorial savannah with dry summer" (As), Aw, "steppe climate" (BS), and "desert climate" (BW) climate types. Moreover, some climate types, including Af, "equatorial monsoon" (Am), BS, BW, and "tundra climate" (ET), were susceptible to temporal climate changes, especially in the period 1976-2009.

  10. Evaluating a Human Rights-Based Advocacy Approach to Expanding Access to Pain Medicines and Palliative Care: Global Advocacy and Case Studies from India, Kenya, and Ukraine.

    Science.gov (United States)

    Lohman, Diederik; Amon, Joseph J

    2015-12-10

    Palliative care has been defined as care that is person-centered and attentive to physical symptoms and psychological, social, and existential distress in patients with severe or life-threatening illness. The identification of access to palliative care and pain treatment as a human rights issue first emerged among palliative care advocates, physicians, and lawyers in the 1990s, with a basis in the right to health and the right to be free from cruel, inhuman, and degrading treatment. Using a case study approach, we evaluate the results of a human rights-based advocacy approach on access to pain medicine and palliative care in India, Kenya, and Ukraine. In each country, human rights advocacy helped raise awareness of the issue, identify structural barriers to care, define government obligations, and contribute to the reform of laws, policies, and practices impeding the availability of palliative care services. In addition, advocacy efforts stimulated civil society engagement and high-level political leadership that fostered the implementation of human rights-based palliative care programs. Globally, access to palliative care was increasingly recognized by human rights bodies and within global health and drug policy organizations as a government obligation central to the right to health. Copyright © 2015 Lohman, Amon. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.

  11. Speciation despite globally overlapping distributions in Penicillium chrysogenum: the population genetics of Alexander Fleming's lucky fungus.

    Science.gov (United States)

    Henk, D A; Eagle, C E; Brown, K; Van Den Berg, M A; Dyer, P S; Peterson, S W; Fisher, M C

    2011-10-01

    Eighty years ago, Alexander Fleming described the antibiotic effects of a fungus that had contaminated his bacterial culture, kick starting the antimicrobial revolution. The fungus was later ascribed to a putatively globally distributed asexual species, Penicillium chrysogenum. Recently, the species has been shown to be genetically diverse, and possess mating-type genes. Here, phylogenetic and population genetic analyses show that this apparently ubiquitous fungus is actually composed of at least two genetically distinct species with only slight differences detected in physiology. We found each species in air and dust samples collected in and around St Mary's Hospital where Fleming worked. Genotyping of 30 markers across the genome showed that preserved fungal material from Fleming's laboratory was nearly identical to derived strains currently in culture collections and in the same distinct species as a wild progenitor strain of current penicillin producing industrial strains rather than the type species P. chrysogenum. Global samples of the two most common species were found to possess mating-type genes in a near 1:1 ratio, and show evidence of recombination with little geographic population subdivision evident. However, no hybridization was detected between the species despite an estimated time of divergence of less than 1MYA. Growth studies showed significant interspecific inhibition by P. chrysogenum of the other common species, suggesting that competition may facilitate species maintenance despite globally overlapping distributions. Results highlight under-recognized diversity even among the best-known fungal groups and the potential for speciation despite overlapping distribution. © 2011 Blackwell Publishing Ltd.

  12. RGloVe: An Improved Approach of Global Vectors for Distributional Entity Relation Representation

    Directory of Open Access Journals (Sweden)

    Ziyan Chen

    2017-04-01

    Full Text Available Most of the previous works on relation extraction between named entities are often limited to extracting the pre-defined types; which are inefficient for massive unlabeled text data. Recently; with the appearance of various distributional word representations; unsupervised methods for many natural language processing (NLP tasks have been widely researched. In this paper; we focus on a new finding of unsupervised relation extraction; which is called distributional relation representation. Without requiring the pre-defined types; distributional relation representation aims to automatically learn entity vectors and further estimate semantic similarity between these entities. We choose global vectors (GloVe as our original model to train entity vectors because of its excellent balance between local context and global statistics in the whole corpus. In order to train model more efficiently; we improve the traditional GloVe model by using cosine similarity between entity vectors to approximate the entity occurrences instead of dot product. Because cosine similarity can convert vector to unit vector; it is intuitively more reasonable and more easily converge to a local optimum. We call the improved model RGloVe. Experimental results on a massive corpus of Sina News show that our proposed model outperforms the traditional global vectors. Finally; a graph database of Neo4j is introduced to store these relationships between named entities. The most competitive advantage of Neo4j is that it provides a highly accessible way to query the direct and indirect relationships between entities.

  13. Global distribution of mean age of stratospheric air from MIPAS SF6 measurements

    Directory of Open Access Journals (Sweden)

    H. Fischer

    2008-02-01

    Full Text Available Global distributions of profiles of sulphur hexafluoride (SF6 have been retrieved from limb emission spectra recorded by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS on Envisat covering the period September 2002 to March 2004. Individual SF6 profiles have a precision of 0.5 pptv below 25 km altitude and a vertical resolution of 4–6 km up to 35 km altitude. These data have been validated versus in situ observations obtained during balloon flights of a cryogenic whole-air sampler. For the tropical troposphere a trend of 0.230±0.008 pptv/yr has been derived from the MIPAS data, which is in excellent agreement with the trend from ground-based flask and in situ measurements from the National Oceanic and Atmospheric Administration Earth System Research Laboratory, Global Monitoring Division. For the data set currently available, based on at least three days of data per month, monthly 5° latitude mean values have a 1σ standard error of 1%. From the global SF6 distributions, global daily and monthly distributions of the apparent mean age of air are inferred by application of the tropical tropospheric trend derived from MIPAS data. The inferred mean ages are provided for the full globe up to 90° N/S, and have a 1σ standard error of 0.25 yr. They range between 0 (near the tropical tropopause and 7 years (except for situations of mesospheric intrusions and agree well with earlier observations. The seasonal variation of the mean age of stratospheric air indicates episodes of severe intrusion of mesospheric air during each Northern and Southern polar winter observed, long-lasting remnants of old, subsided polar winter air over the spring and summer poles, and a rather short period of mixing with midlatitude air and/or upward transport during fall in October/November (NH and April/May (SH, respectively, with small latitudinal gradients, immediately before the new polar vortex starts to form. The mean age distributions further

  14. Partition expanders

    Czech Academy of Sciences Publication Activity Database

    Gavinsky, Dmitry; Pudlák, Pavel

    2017-01-01

    Roč. 60, č. 3 (2017), s. 378-395 ISSN 1432-4350 R&D Projects: GA ČR GBP202/12/G061 Institutional support: RVO:67985840 Keywords : expanders * pseudorandomness * communication complexity Subject RIV: BA - General Mathematics Impact factor: 0.645, year: 2016 http://link.springer.com/article/10.1007%2Fs00224-016-9738-5

  15. Climate Change Influences on the Global Potential Distribution of Bluetongue Virus.

    Directory of Open Access Journals (Sweden)

    Abdallah M Samy

    Full Text Available The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV is classified among category "A" diseases notifiable to the World Organization of Animal Health (OIE, and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs for four representative concentration pathways (RCPs. The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease's current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i; all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia.

  16. Climate Change Influences on the Global Potential Distribution of Bluetongue Virus

    Science.gov (United States)

    Samy, Abdallah M.; Peterson, A. Townsend

    2016-01-01

    The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV) is classified among category “A” diseases notifiable to the World Organization of Animal Health (OIE), and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs) for four representative concentration pathways (RCPs). The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease’s current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i); all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia. PMID:26959424

  17. Distributed team cohesion – not an oxymoron. The impact of information and communications technologies on teamness in globally distributed IT projects

    OpenAIRE

    Olga Stawnicza

    2015-01-01

    Globally distributed IT projects are common practice in today’s globalized world. Typically, project team members’ work on interdependent tasks, with a common goal to be achieved as one team. However, being split between multiple locations impedes communication among team members and hampers the development of trust. Information and communications media enable communication between geographically distributed project team members and help to create and maintain trust within project units. Comm...

  18. Global distribution of a key trophic guild contrasts with common latitudinal diversity patterns.

    Science.gov (United States)

    Boyero, Luz; Pearson, Richard G; Dudgeon, David; Graça, Manuel A S; Gessner, Mark O; Albariño, Ricardo J; Ferreira, Verónica; Yule, Catherine M; Boulton, Andrew J; Arunachalam, Muthukumarasamy; Callisto, Marcos; Chauvet, Eric; Ramírez, Alonso; Chará, Julián; Moretti, Marcelo S; Gonçalves, José F; Helson, Julie E; Chará-Serna, Ana M; Encalada, Andrea C; Davies, Judy N; Lamothe, Sylvain; Cornejo, Aydeè; Li, Aggie O Y; Buria, Leonardo M; Villanueva, Verónica D; Zúñiga, María C; Pringle, Catherine M

    2011-09-01

    Most hypotheses explaining the general gradient of higher diversity toward the equator are implicit or explicit about greater species packing in the tropics. However, global patterns of diversity within guilds, including trophic guilds (i.e., groups of organisms that use similar food resources), are poorly known. We explored global diversity patterns of a key trophic guild in stream ecosystems, the detritivore shredders. This was motivated by the fundamental ecological role of shredders as decomposers of leaf litter and by some records pointing to low shredder diversity and abundance in the tropics, which contrasts with diversity patterns of most major taxa for which broad-scale latitudinal patterns haven been examined. Given this evidence, we hypothesized that shredders are more abundant and diverse in temperate than in tropical streams, and that this pattern is related to the higher temperatures and lower availability of high-quality leaf litter in the tropics. Our comprehensive global survey (129 stream sites from 14 regions on six continents) corroborated the expected latitudinal pattern and showed that shredder distribution (abundance, diversity and assemblage composition) was explained by a combination of factors, including water temperature (some taxa were restricted to cool waters) and biogeography (some taxa were more diverse in particular biogeographic realms). In contrast to our hypothesis, shredder diversity was unrelated to leaf toughness, but it was inversely related to litter diversity. Our findings markedly contrast with global trends of diversity for most taxa, and with the general rule of higher consumer diversity at higher levels of resource diversity. Moreover, they highlight the emerging role of temperature in understanding global patterns of diversity, which is of great relevance in the face of projected global warming.

  19. Expanding versus non expanding universe

    CERN Document Server

    Alfonso-Faus, Antonio

    2012-01-01

    In cosmology the number of scientists using the framework of an expanding universe is very high. This model, the big-bang, is now overwhelmingly present in almost all aspects of society. It is the main stream cosmology of today. A small number of scientists are researching on the possibility of a non-expanding universe. The existence of these two groups, one very large and the other very small, is a good proof of the use of the scientific method: it does not drive to an absolute certainty. All models have to be permanently validated, falsified. Ockham's razor, a powerful philosophical tool, will probably change the amount of scientists working in each of these groups. We present here a model where a big-bang is unnecessary. It ends, in a finite time, in a second INFLATION, or a disaggregation to infinity. We also discuss the possibilities of a non-expanding universe model. Only a few references will be cited, mainly concerned with our own work in the past, thus purposely avoiding citing the many thousands of ...

  20. [Predicting the impact of global warming on the geographical distribution pattern of Quercus variabilis in China].

    Science.gov (United States)

    Li, Yao; Zhang, Xing-wang; Fang, Yan-ming

    2014-12-01

    The geographical distribution of Quercus variabilis in China with its climate characteristics was analyzed based on DIVA-GIS which was also used to estimate the response of future potential distribution to global warming by Bioclim and Domain models. Analysis results showed the geographical distribution of Q. variabilis could be divided into 7 subregions: Henduan Mountains, Yunnan-Guizhou Plateau, North China, East China, Liaodong-Shandong Peninsula, Taiwan Island, and Qinling-Daba Mountains. These subregions are across 7 temperature zones, 2 moisture regions and 17 climatic subregions, including 8 climate types. The modern abundance center of Q. variabilis is Qinling, Daba and Funiu mountains. The condition of mean annual temperature 7.5-19.8 degrees C annual precipitation 471-1511 mm, is suitable for Q. variabilis. Areas under the receiver operating characteristic curve (AUC values), of Domain and Boiclim models were 0.910, 0.779; the former predicted that the potential regions of high suitability for Q. variabilis are Qinling, Daba, Funiu, Tongbai, and Dabie mountains, eastern and western Yunnan-Guizhou Plateau, hills of southern Jiangsu and Anhui, part of the mountains in North China. Global warming might lead to the shrinking in suitable region and retreating from the south for Q. variabilis.

  1. Distribution and habitat of brazilian-pine according to global climate change

    Directory of Open Access Journals (Sweden)

    Marcos Silveira Wrege

    2017-09-01

    Full Text Available Araucaria angustifolia (Bertol. O. Kuntze., also known as brazilian-pine, is a forest native species from Brazil. A. angustifolia is more vulnerable to global climate change, considering it is living in cold and humid mountain regions from southern and southeastern Brazil. Among the native Brazilian forest species, it presents one of the greatest growth and genetic gain potential. It shows excellent wood quality and can still be used in human and animal food, presenting great economic, social and environmental value. In order to determine current distribution of the species and better know its habitat, we worked in the regions representing the borders of natural occurrence, identifying populations and getting trees altitude and geographycal position. Field information along with secondary data from the Environmental Information Center (CRIA were used to map current distribution of brazilian-pine and to project the distribution in the next decades, with the projection of future climate scenarios. Mapping studies of ecological niches in present and future climate scenarios characterizing the environments in which they are living is essential for a better understanding of the risks of species extinction and which mitigating measures could be adequate to reduce the impacts of global climate change on species, thus contributing to the conservation and knowledge of this important species.

  2. Global Dynamics of Virus Infection Model with Antibody Immune Response and Distributed Delays

    Directory of Open Access Journals (Sweden)

    A. M. Elaiw

    2013-01-01

    Full Text Available We present qualitative behavior of virus infection model with antibody immune response. The incidence rate of infection is given by saturation functional response. Two types of distributed delays are incorporated into the model to account for the time delay between the time when uninfected cells are contacted by the virus particle and the time when emission of infectious (matures virus particles. Using the method of Lyapunov functional, we have established that the global stability of the steady states of the model is determined by two threshold numbers, the basic reproduction number R0 and antibody immune response reproduction number R1. We have proven that if R0≤1, then the uninfected steady state is globally asymptotically stable (GAS, if R1≤11, then the infected steady state with antibody immune response is GAS.

  3. A quantitative analysis of the causes of the global climate change research distribution

    DEFF Research Database (Denmark)

    Pasgaard, Maya; Strange, Niels

    2013-01-01

    the poorer, fragile and more vulnerable regions of the world. A quantitative keywords analysis of all publications shows that different knowledge domains and research themes dominate across regions, reflecting the divergent global concerns in relation to climate change. In general, research on climate change......During the last decades of growing scientific, political and public attention to global climate change, it has become increasingly clear that the present and projected impacts from climate change, and the ability adapt to the these changes, are not evenly distributed across the globe. This paper...... investigates whether the need for knowledge on climate changes in the most vulnerable regions of the world is met by the supply of knowledge measured by scientific research publications from the last decade. A quantitative analysis of more than 15,000 scientific publications from 197 countries investigates...

  4. The global distribution of fatal pesticide self-poisoning: systematic review

    DEFF Research Database (Denmark)

    Gunnell, David; Eddleston, Michael; Phillips, Michael R

    2007-01-01

    BACKGROUND: Evidence is accumulating that pesticide self-poisoning is one of the most commonly used methods of suicide worldwide, but the magnitude of the problem and the global distribution of these deaths is unknown. METHODS: We have systematically reviewed the worldwide literature to estimate...... the number of pesticide suicides in each of the World Health Organisation's six regions and the global burden of fatal self-poisoning with pesticides. We used the following data sources: Medline, EMBASE and psycINFO (1990-2007), papers cited in publications retrieved, the worldwide web (using Google) and our...... personal collections of papers and books. Our aim was to identify papers enabling us to estimate the proportion of a country's suicides due to pesticide self-poisoning. RESULTS: We conservatively estimate that there are 258,234 (plausible range 233,997 to 325,907) deaths from pesticide self-poisoning...

  5. Modelling global distribution, risk and mitigation strategies of floating plastic pollution

    Science.gov (United States)

    van Sebille, Erik; Wilcox, Chris; Sherman, Peter; Hardesty, Britta Denise; Lavender Law, Kara

    2016-04-01

    Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on the North Pacific and North Atlantic accumulation zones, with much sparser coverage elsewhere. Here, we use the largest dataset of microplastic measurements assembled to date to assess the confidence we can have in global estimates of microplastic abundance and mass. We use a rigorous statistical framework to standardise a global dataset of plastic marine debris measured using surface-trawling plankton nets and couple this with three different ocean circulation models to spatially interpolate the observations. Our estimates show that the accumulated number of microplastic particles in 2014 ranges from 15 to 51 trillion particles, weighing between 93 and 236 thousand metric tons. A large fraction of the uncertainty in these estimates comes from sparse sampling in coastal and Southern Hemisphere regions. We then use this global distribution of small floating plastic debris to map out where in the ocean the risk to marine life (in particular seabirds and plankton growth) is greatest, using a quantitative risk framework. We show that the largest risk occurs not necessarily in regions of high plastic concentration, but rather in regions of extensive foraging with medium-high plastic concentrations such as coastal upwelling regions and the Southern Ocean. Finally, we use the estimates of distribution to investigate where in the ocean plastic can most optimally be removed, assuming hypothetical clean-up booms following the ideas from The Ocean Cleanup project. We show that mitigation of the plastic problem can most aptly be done near coastlines, particularly in Asia, rather than in the centres of the gyres. Based on these results, we propose more focus on the coastal zones when

  6. Mapping of CO2 at High Spatiotemporal Resolution using Satellite Observations: Global distributions from OCO-2

    Science.gov (United States)

    Hammerling, Dorit M.; Michalak, Anna M.; Kawa, S. Randolph

    2012-01-01

    Satellite observations of CO2 offer new opportunities to improve our understanding of the global carbon cycle. Using such observations to infer global maps of atmospheric CO2 and their associated uncertainties can provide key information about the distribution and dynamic behavior of CO2, through comparison to atmospheric CO2 distributions predicted from biospheric, oceanic, or fossil fuel flux emissions estimates coupled with atmospheric transport models. Ideally, these maps should be at temporal resolutions that are short enough to represent and capture the synoptic dynamics of atmospheric CO2. This study presents a geostatistical method that accomplishes this goal. The method can extract information about the spatial covariance structure of the CO2 field from the available CO2 retrievals, yields full coverage (Level 3) maps at high spatial resolutions, and provides estimates of the uncertainties associated with these maps. The method does not require information about CO2 fluxes or atmospheric transport, such that the Level 3 maps are informed entirely by available retrievals. The approach is assessed by investigating its performance using synthetic OCO-2 data generated from the PCTM/ GEOS-4/CASA-GFED model, for time periods ranging from 1 to 16 days and a target spatial resolution of 1deg latitude x 1.25deg longitude. Results show that global CO2 fields from OCO-2 observations can be predicted well at surprisingly high temporal resolutions. Even one-day Level 3 maps reproduce the large-scale features of the atmospheric CO2 distribution, and yield realistic uncertainty bounds. Temporal resolutions of two to four days result in the best performance for a wide range of investigated scenarios, providing maps at an order of magnitude higher temporal resolution relative to the monthly or seasonal Level 3 maps typically reported in the literature.

  7. Two new species of Nitocrella (Crustacea, Copepoda, Harpacticoida from groundwaters of northwestern Australia expand the geographic range of the genus in a global hotspot of subterranean biodiversity

    Directory of Open Access Journals (Sweden)

    Danny Tang

    2016-11-01

    Full Text Available In Australia, the Ameiridae is the most diverse harpacticoid family in groundwater, with 35 species hitherto reported. In this study, we describe two new species belonging to the “vasconica”-group of the ameirid genus Nitocrella based on specimens collected from groundwaters near mine sites in the Pilbara and Great Sandy Desert regions of northwestern Australia. Nitocrella knotti sp. n. can be distinguished from related taxa by having two setae on the antennal exopod, four armature elements on the distal endopodal segment of leg 2, four armature elements on the distal endopodal segment of leg 3, three armature elements on the distal endopodal segment of leg 4, and three setae on the basoendopodal lobe of leg 5. Nitocrella karanovici sp. n. differs from its congeners by having a short outer spine and long inner seta on the distal endopodal segment of leg 2, three armature elements on the distal endopodal segment of leg 3, and four setae on the basoendopodal lobe of leg 5 in the female. This study is of biogeographic interest in providing the first documentation of the genus Nitocrella from the Pilbara and Great Sandy Desert regions. Both new species of Nitocrella are recorded from restricted localities and appear to be short-range endemics, thus making them potentially vulnerable to environmental changes and threatening processes such as mining. The distribution range of N. karanovici sp. n. coincides with the centre of diversity of the Ethel Gorge aquifer stygobiont community, a globally significant hotspot which is listed as endangered.

  8. Insects at low pressure: applications to artificial ecosystems and implications for global windborne distribution

    Science.gov (United States)

    Cockell, C.; Catling, D.; Waites, H.

    1999-01-01

    Insects have a number of potential roles in closed-loop life support systems. In this study we examined the tolerance of a range of insect orders and life stages to drops in atmospheric pressure using a terrestrial atmosphere. We found that all insects studied could tolerate pressures down to 100 mb. No effects on insect respiration were noted down to 500 mb. Pressure toleration was not dependent on body volume. Our studies demonstrate that insects are compatible with plants in low-pressure artificial and closed-loop ecosystems. The results also have implications for arthropod colonization and global distribution on Earth.

  9. Synthesis and biology of cyclic imine toxins, an emerging class of potent, globally distributed marine toxins.

    Science.gov (United States)

    Stivala, Craig E; Benoit, Evelyne; Aráoz, Rómulo; Servent, Denis; Novikov, Alexei; Molgó, Jordi; Zakarian, Armen

    2015-03-01

    From a small group of exotic compounds isolated only two decades ago, Cyclic Imine (CI) toxins have become a major class of marine toxins with global distribution. Their distinct chemical structure, biological mechanism of action, and intricate chemistry ensures that CI toxins will continue to be the subject of fascinating fundamental studies in the broad fields of chemistry, chemical biology, and toxicology. The worldwide occurrence of potent CI toxins in marine environments, their accumulation in shellfish, and chemical stability are important considerations in assessing risk factors for human health. This review article aims to provide an account of chemistry, biology, and toxicology of CI toxins from their discovery to the present day.

  10. Earthquake rate and magnitude distributions of great earthquakes for use in global forecasts

    Science.gov (United States)

    Kagan, Yan Y.; Jackson, David D.

    2016-07-01

    We have obtained new results in the statistical analysis of global earthquake catalogues with special attention to the largest earthquakes, and we examined the statistical behaviour of earthquake rate variations. These results can serve as an input for updating our recent earthquake forecast, known as the `Global Earthquake Activity Rate 1' model (GEAR1), which is based on past earthquakes and geodetic strain rates. The GEAR1 forecast is expressed as the rate density of all earthquakes above magnitude 5.8 within 70 km of sea level everywhere on earth at 0.1 × 0.1 degree resolution, and it is currently being tested by the Collaboratory for Study of Earthquake Predictability. The seismic component of the present model is based on a smoothed version of the Global Centroid Moment Tensor (GCMT) catalogue from 1977 through 2013. The tectonic component is based on the Global Strain Rate Map, a `General Earthquake Model' (GEM) product. The forecast was optimized to fit the GCMT data from 2005 through 2012, but it also fit well the earthquake locations from 1918 to 1976 reported in the International Seismological Centre-Global Earthquake Model (ISC-GEM) global catalogue of instrumental and pre-instrumental magnitude determinations. We have improved the recent forecast by optimizing the treatment of larger magnitudes and including a longer duration (1918-2011) ISC-GEM catalogue of large earthquakes to estimate smoothed seismicity. We revised our estimates of upper magnitude limits, described as corner magnitudes, based on the massive earthquakes since 2004 and the seismic moment conservation principle. The new corner magnitude estimates are somewhat larger than but consistent with our previous estimates. For major subduction zones we find the best estimates of corner magnitude to be in the range 8.9 to 9.6 and consistent with a uniform average of 9.35. Statistical estimates tend to grow with time as larger earthquakes occur. However, by using the moment conservation

  11. The 3rd Global Summit of Research Institutes for Disaster Risk Reduction:Expanding the Platform for Bridging Science and Policy Making

    National Research Council Canada - National Science Library

    Andrew Collins Hirokazu Tatano Wilma James Chadia Wannous Kaoru Takara Virginia Murray Charles Scawthorn Jim Mori Sarah Aziz Khalid M.Mosalam Stefan Hochrainer-Stigler Irasema Alcántara-Ayala Elisabeth Krausmann Wei-Sen Li Ana Maria Cruz Subhajyoti Samaddar Tom De Groeve Yuichi Ono Kelvin Berryman Koji Suzuki Mark Ashley Parry Peter McGowran John G.Rees

    2017-01-01

    The Global Alliance of Disaster Research Institutes held its 3rd Global Summit of Research Institutes for Disaster Risk Reduction at the Disaster Prevention Research Institute,Kyoto University,Japan,19–21 March,2017...

  12. Assessing water resources in Azerbaijan using a local distributed model forced and constrained with global data

    Science.gov (United States)

    Bouaziz, Laurène; Hegnauer, Mark; Schellekens, Jaap; Sperna Weiland, Frederiek; ten Velden, Corine

    2017-04-01

    In many countries, data is scarce, incomplete and often not easily shared. In these cases, global satellite and reanalysis data provide an alternative to assess water resources. To assess water resources in Azerbaijan, a completely distributed and physically based hydrological wflow-sbm model was set-up for the entire Kura basin. We used SRTM elevation data, a locally available river map and one from OpenStreetMap to derive the drainage direction network at the model resolution of approximately 1x1 km. OpenStreetMap data was also used to derive the fraction of paved area per cell to account for the reduced infiltration capacity (c.f. Schellekens et al. 2014). We used the results of a global study to derive root zone capacity based on climate data (Wang-Erlandsson et al., 2016). To account for the variation in vegetation cover over the year, monthly averages of Leaf Area Index, based on MODIS data, were used. For the soil-related parameters, we used global estimates as provided by Dai et al. (2013). This enabled the rapid derivation of a first estimate of parameter values for our hydrological model. Digitized local meteorological observations were scarce and available only for limited time period. Therefore several sources of global meteorological data were evaluated: (1) EU-WATCH global precipitation, temperature and derived potential evaporation for the period 1958-2001 (Harding et al., 2011), (2) WFDEI precipitation, temperature and derived potential evaporation for the period 1979-2014 (by Weedon et al., 2014), (3) MSWEP precipitation (Beck et al., 2016) and (4) local precipitation data from more than 200 stations in the Kura basin were available from the NOAA website for a period up to 1991. The latter, together with data archives from Azerbaijan, were used as a benchmark to evaluate the global precipitation datasets for the overlapping period 1958-1991. By comparing the datasets, we found that monthly mean precipitation of EU-WATCH and WFDEI coincided well

  13. Global distribution of energetic proton precipitations equatorward of the boundary of isotropic fluxes

    Science.gov (United States)

    Semenova, N. V.; Yahnina, T. A.; Yahnin, A. G.; Demekhov, A. G.

    2017-07-01

    Based on data of the NOAA POES satellite, the global distribution of the occurrence rate of precipitations of energetic protons ( E > 30 keV) equatorward of the boundary of isotropic fluxes has been constructed for the first time. It has been shown that the occurrence rate of proton precipitations inside the zone of anisotropic fluxes is maximum in daytime hours (1100-1600 MLT) at latitudes L = 6-9 and decreases in evening and morning hours. Comparison of the obtained results about proton precipitations with the spatial distribution of the occurrence rate of electromagnetic ion-cyclotron (EMIC) waves in the equatorial magnetosphere according to results of satellite observations demonstrates a close relationship between them. This corroborates that precipitations of energetic protons equatorward of the boundary of isotropic fluxes are a consequence of the development of the ion-cyclotron instability in the equatorial magnetosphere.

  14. Impact of hadronic and nuclear corrections on global analysis of spin-dependent parton distributions

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez-Delgado, Pedro [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Accardi, Alberto [Hampton University, Hampton, VA (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Melnitchouk, Wally [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2014-02-01

    We present the first results of a new global next-to-leading order analysis of spin-dependent parton distribution functions from the most recent world data on inclusive polarized deep-inelastic scattering, focusing in particular on the large-x and low-Q^2 regions. By directly fitting polarization asymmetries we eliminate biases introduced by using polarized structure function data extracted under nonuniform assumptions for the unpolarized structure functions. For analysis of the large-x data we implement nuclear smearing corrections for deuterium and 3He nuclei, and systematically include target mass and higher twist corrections to the g_1 and g_2 structure functions at low Q^2. We also explore the effects of Q^2 and W^2 cuts in the data sets, and the potential impact of future data on the behavior of the spin-dependent parton distributions at large x.

  15. Global trends in the fluorescence characteristics and distribution of marine dissolved organic matter

    DEFF Research Database (Denmark)

    Jørgensen, Linda; Stedmon, Colin; Kragh, Theis

    2011-01-01

    A fraction of dissolved organic matter (DOM) is able to fluoresce. This ability has been used in the present study to investigate the characteristics and distribution of different DOM fractions. A unique global dataset revealed seven different fluorescent fractions of DOM: two humic-like, four...... amino acid-like and one chemically uncharacterized. The spectral characteristics of the amino acid-like fractions resemble those of pure tryptophan, tyrosine and phenylalanine. The fluorescence intensities of these amino acid-like fractions are highest in the surface waters, rapidly decreasing....... These observations imply a link to dark ocean microbial remineralization and indicate that the major source of humic-like compounds is microbial turnover of organic matter. The results of the present study show that the distribution of the humic-like DOM fractions is a balance between supply from continental run off...

  16. Schistosomes with wings: how host phylogeny and ecology shape the global distribution of Trichobilharzia querquedulae (Schistosomatidae).

    Science.gov (United States)

    Ebbs, Erika T; Loker, Eric S; Davis, Norm E; Flores, Veronica; Veleizan, Aylen; Brant, Sara V

    2016-09-01

    Migratory waterfowl play an important role in the maintenance and spread of zoonotic diseases worldwide. An example is cercarial dermatitis, caused when larval stages of schistosomes that normally develop in birds penetrate human skin. Members of the genus Trichobilharzia (Schistosomatidae), transmitted mainly by ducks, are considered to be major etiological agents of cercarial dermatitis globally. To better understand the diversity and distribution of Trichobilharzia spp., we surveyed ducks from the United States, eastern Canada, Argentina, South Africa and New Zealand. To aid in species identification of the Trichobilharzia worms recovered, regions of the Cox1, ND4 and ITS1 were sequenced. Furthermore, we provide molecular phylogenetic evidence for the cosmopolitan distribution and trans-hemispheric gene flow for one species, Trichobilharzia querquedulae, previously thought to be restricted to North America. These new samples from endemic non-migratory duck species indicate that T. querquedulae transmission occurs within each of the regions we sampled and that it is specific to the blue-winged+silver teal duck clade. Prevalence within this host group is >95% across the known range of T. querquedulae, indicating that transmission is common. Genetic divergence is evenly distributed among continents, and no phylogenetic structure associated with geography was observed. The results provide strong support for the global distribution and transmission of T. querquedulae and represent, to our knowledge, the first report of a cosmopolitan schistosome confirmed by genetic data. These data are the first known to support trans-hemispheric genetic exchange in a species responsible for causing cercarial dermatitis, indicating that the epidemiology of this group of poorly known zoonotic parasites is more complex than previously expected. Copyright © 2016 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

  17. Synthetic Assessment of Global Distribution of Vulnerability to Climate Change: Maps and Data, 2005, 2050, and 2100

    Data.gov (United States)

    National Aeronautics and Space Administration — Synthetic Assessment of Global Distribution of Vulnerability to Climate Change: Maps and Data, 2005, 2050, and 2100 consist of maps and vulnerability index to...

  18. Expanded Dengue.

    Science.gov (United States)

    Kadam, D B; Salvi, Sonali; Chandanwale, Ajay

    2016-07-01

    The World Health Organization (WHO) has coined the term expanded dengue to describe cases which do not fall into either dengue shock syndrome or dengue hemorrhagic fever. This has incorporated several atypical findings of dengue. Dengue virus has not been enlisted as a common etiological agent in several conditions like encephalitis, Guillain Barre syndrome. Moreover it is a great mimic of co-existing epidemics like Malaria, Chikungunya and Zika virus disease, which are also mosquito-borne diseases. The atypical manifestations noted in dengue can be mutisystemic and multifacetal. In clinical practice, the occurrence of atypical presentation should prompt us to investigate for dengue. Knowledge of expanded dengue helps to clinch the diagnosis of dengue early, especially during ongoing epidemics, avoiding further battery of investigations. Dengue has proved to be the epidemic with the ability to recur and has a diverse array of presentation as seen in large series from India, Srilanka, Indonesia and Taiwan. WHO has given the case definition of dengue fever in their comprehensive guidelines. Accordingly, a probable case is defined as acute febrile illness with two or more of any findings viz. headache, retro-orbital pain, myalgia, arthralgia, rash, hemorrhagic manifestations, leucopenia and supportive serology. There have been cases of patients admitted with fever, altered mentation with or without neck stiffness and pyramidal tract signs. Some had seizures or status epilepticus as presentation. When they were tested for serology, dengue was positive. After ruling out other causes, dengue remained the only culprit. We have come across varied presentations of dengue fever in clinical practice and the present article throws light on atypical manifestations of dengue. © Journal of the Association of Physicians of India 2011.

  19. Geographic patterns of genetic variation in a broadly distributed marine vertebrate: new insights into loggerhead turtle stock structure from expanded mitochondrial DNA sequences.

    Directory of Open Access Journals (Sweden)

    Brian M Shamblin

    Full Text Available Previous genetic studies have demonstrated that natal homing shapes the stock structure of marine turtle nesting populations. However, widespread sharing of common haplotypes based on short segments of the mitochondrial control region often limits resolution of the demographic connectivity of populations. Recent studies employing longer control region sequences to resolve haplotype sharing have focused on regional assessments of genetic structure and phylogeography. Here we synthesize available control region sequences for loggerhead turtles from the Mediterranean Sea, Atlantic, and western Indian Ocean basins. These data represent six of the nine globally significant regional management units (RMUs for the species and include novel sequence data from Brazil, Cape Verde, South Africa and Oman. Genetic tests of differentiation among 42 rookeries represented by short sequences (380 bp haplotypes from 3,486 samples and 40 rookeries represented by long sequences (∼800 bp haplotypes from 3,434 samples supported the distinction of the six RMUs analyzed as well as recognition of at least 18 demographically independent management units (MUs with respect to female natal homing. A total of 59 haplotypes were resolved. These haplotypes belonged to two highly divergent global lineages, with haplogroup I represented primarily by CC-A1, CC-A4, and CC-A11 variants and haplogroup II represented by CC-A2 and derived variants. Geographic distribution patterns of haplogroup II haplotypes and the nested position of CC-A11.6 from Oman among the Atlantic haplotypes invoke recent colonization of the Indian Ocean from the Atlantic for both global lineages. The haplotypes we confirmed for western Indian Ocean RMUs allow reinterpretation of previous mixed stock analysis and further suggest that contemporary migratory connectivity between the Indian and Atlantic Oceans occurs on a broader scale than previously hypothesized. This study represents a valuable model for

  20. Five decades of genome evolution in the globally distributed, extensively antibiotic-resistant Acinetobacter baumannii global clone 1.

    Science.gov (United States)

    Holt, Kathryn; Kenyon, Johanna J; Hamidian, Mohammad; Schultz, Mark B; Pickard, Derek J; Dougan, Gordon; Hall, Ruth

    2016-02-01

    The majority of Acinetobacter baumannii isolates that are multiply, extensively and pan-antibiotic resistant belong to two globally disseminated clones, GC1 and GC2, that were first noticed in the 1970s. Here, we investigated microevolution and phylodynamics within GC1 via analysis of 45 whole-genome sequences, including 23 sequenced for this study. The most recent common ancestor of GC1 arose around 1960 and later diverged into two phylogenetically distinct lineages. In the 1970s, the main lineage acquired the AbaR resistance island, conferring resistance to older antibiotics, via a horizontal gene transfer event. We estimate a mutation rate of ∼5 SNPs genome- 1 year- 1 and detected extensive recombination within GC1 genomes, introducing nucleotide diversity into the population at >20 times the substitution rate (the ratio of SNPs introduced by recombination compared with mutation was 22). The recombination events were non-randomly distributed in the genome and created significant diversity within loci encoding outer surface molecules (including the capsular polysaccharide, the outer core lipooligosaccharide and the outer membrane protein CarO), and spread antimicrobial resistance-conferring mutations affecting the gyrA and parC genes and insertion sequence insertions activating the ampC gene. Both GC1 lineages accumulated resistance to newer antibiotics through various genetic mechanisms, including the acquisition of plasmids and transposons or mutations in chromosomal genes. Our data show that GC1 has diversified into multiple successful extensively antibiotic-resistant subclones that differ in their surface structures. This has important implications for all avenues of control, including epidemiological tracking, antimicrobial therapy and vaccination.

  1. Global distribution of the sickle cell gene and geographical confirmation of the malaria hypothesis

    Science.gov (United States)

    Piel, Frédéric B.; Patil, Anand P.; Howes, Rosalind E.; Nyangiri, Oscar A.; Gething, Peter W.; Williams, Thomas N.; Weatherall, David J.; Hay, Simon I.

    2010-01-01

    It has been 100 years since the first report of sickle haemoglobin (HbS). More than 50 years ago, it was suggested that the gene responsible for this disorder could reach high frequencies because of resistance conferred against malaria by the heterozygous carrier state. This traditional example of balancing selection is known as the 'malaria hypothesis'. However, the geographical relationship between the transmission intensity of malaria and associated HbS burden has never been formally investigated on a global scale. Here, we use a comprehensive data assembly of HbS allele frequencies to generate the first evidence-based map of the worldwide distribution of the gene in a Bayesian geostatistical framework. We compare this map with the pre-intervention distribution of malaria endemicity, using a novel geostatistical area-mean comparison. We find geographical support for the malaria hypothesis globally; the relationship is relatively strong in Africa but cannot be resolved in the Americas or in Asia. PMID:21045822

  2. The Global Experience of Development of the Theory of Spatial Distribution of Productive Forces

    Directory of Open Access Journals (Sweden)

    Heiman Oleh A.

    2016-01-01

    Full Text Available The publication is aimed at theoretical generalization of the global experience of development of the theory of spatial distribution of productive forces as the basis of regional economy. Considering the evolution of scientific views on the spatial development of territories, taking account of the particularities of the distribution of production, one can allocate and identify several paradigms, which replaced each other, but preserved their connection with the placement of productive forces. Each one of these paradigms or all of them as a whole provide an example of a single historical process associated with the productive forces. Characteristic of a methodology based on the spatiotemporal paradigm is consideration of both time and space factors, which, in substance, take on the qualities of economic categories. Speaking of the use of theoretical developments in the practice of regional development, it should be specified that programs, strategies and other regulations must take into account the linkage between the progressive and the negative trends as well as cyclical nature of economic development, including the global economy, identify the factors that accelerate or retard the passage of every evolutionary spiral, and observe consistency of the productive forces of region with the technological patterns of production.

  3. Global distribution and environmental suitability for chikungunya virus, 1952 to 2015.

    Science.gov (United States)

    Nsoesie, E O; Kraemer, M U; Golding, N; Pigott, D M; Brady, O J; Moyes, C L; Johansson, M A; Gething, P W; Velayudhan, R; Khan, K; Hay, S I; Brownstein, J S

    2016-05-19

    Chikungunya fever is an acute febrile illness caused by the chikungunya virus (CHIKV), which is transmitted to humans by Aedes mosquitoes. Although chikungunya fever is rarely fatal, patients can experience debilitating symptoms that last from months to years. Here we comprehensively assess the global distribution of chikungunya and produce high-resolution maps, using an established modelling framework that combines a comprehensive occurrence database with bespoke environmental correlates, including up-to-date Aedes distribution maps. This enables estimation of the current total population-at-risk of CHIKV transmission and identification of areas where the virus may spread to in the future. We identified 94 countries with good evidence for current CHIKV presence and a set of countries in the New and Old World with potential for future CHIKV establishment, demonstrated by high environmental suitability for transmission and in some cases previous sporadic reports. Aedes aegypti presence was identified as one of the major contributing factors to CHIKV transmission but significant geographical heterogeneity exists. We estimated 1.3 billion people are living in areas at-risk of CHIKV transmission. These maps provide a baseline for identifying areas where prevention and control efforts should be prioritised and can be used to guide estimation of the global burden of CHIKV.

  4. Global Distribution, Public Health and Clinical Impact of the Protozoan Pathogen Cryptosporidium

    Directory of Open Access Journals (Sweden)

    Lorenza Putignani

    2010-01-01

    Full Text Available Cryptosporidium spp. are coccidians, oocysts-forming apicomplexan protozoa, which complete their life cycle both in humans and animals, through zoonotic and anthroponotic transmission, causing cryptosporidiosis. The global burden of this disease is still underascertained, due to a conundrum transmission modality, only partially unveiled, and on a plethora of detection systems still inadequate or only partially applied for worldwide surveillance. In children, cryptosporidiosis encumber is even less recorded and often misidentified due to physiological reasons such as early-age unpaired immunological response. Furthermore, malnutrition in underdeveloped countries or clinical underestimation of protozoan etiology in developed countries contribute to the underestimation of the worldwide burden. Principal key indicators of the parasite distribution were associated to environmental (e.g., geographic and temporal clusters, etc. and host determinants of the infection (e.g., age, immunological status, travels, community behaviours. The distribution was geographically mapped to provide an updated picture of the global parasite ecosystems. The present paper aims to provide, by a critical analysis of existing literature, a link between observational epidemiological records and new insights on public health, and diagnostic and clinical impact of cryptosporidiosis.

  5. The regional distribution of anxiety disorders: implications for the Global Burden of Disease Study, 2010.

    Science.gov (United States)

    Baxter, Amanda J; Vos, Theo; Scott, Kate M; Norman, Rosana E; Flaxman, Abraham D; Blore, Jed; Whiteford, Harvey A

    2014-12-01

    Anxiety disorders are increasingly acknowledged as a global health issue however an accurate picture of prevalence across populations is lacking. Empirical data are incomplete and inconsistent so alternate means of estimating prevalence are required to inform estimates for the new Global Burden of Disease Study 2010. We used a Bayesian meta-regression approach which included empirical epidemiological data, expert prior information, study covariates and population characteristics. Reported are global and regional point prevalence for anxiety disorders in 2010. Point prevalence of anxiety disorders differed by up to three-fold across world regions, ranging between 2.1% (1.8-2.5%) in East Asia and 6.1% (5.1-7.4%) in North Africa/Middle East. Anxiety was more common in Latin America; high income regions; and regions with a history of recent conflict. There was considerable uncertainty around estimates, particularly for regions where no data were available. Future research is required to examine whether variations in regional distributions of anxiety disorders are substantive differences or an artefact of cultural or methodological differences. This is a particular imperative where anxiety is consistently reported to be less common, and where it appears to be elevated, but uncertainty prevents the reporting of conclusive estimates. Copyright © 2014 John Wiley & Sons, Ltd.

  6. Technology Resource, Distribution, and Development Characteristics of Global Influenza Virus Vaccine: A Patent Bibliometric Analysis

    Science.gov (United States)

    Liu, Long; Yan, Zhe; Tao, Lixin; Guo, Xiuhua; Luo, Yanxia; Yan, Aoshuang

    2015-01-01

    Influenza virus vaccine (IVV) is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a) designs the technology classification system and search strategy for the identification of IVV; and (b) presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO) patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation. PMID:26372160

  7. Technology Resource, Distribution, and Development Characteristics of Global Influenza Virus Vaccine: A Patent Bibliometric Analysis.

    Science.gov (United States)

    Chen, Ning; Liu, Yun; Cheng, Yijie; Liu, Long; Yan, Zhe; Tao, Lixin; Guo, Xiuhua; Luo, Yanxia; Yan, Aoshuang

    2015-01-01

    Influenza virus vaccine (IVV) is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a) designs the technology classification system and search strategy for the identification of IVV; and (b) presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO) patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation.

  8. Nested Global Inversion for the Carbon Flux Distribution in Canada and USA from 1994 to 2003

    Science.gov (United States)

    Chen, J. M.; Deng, F.; Ishizawa, M.; Ju, W.; Mo, G.; Chan, D.; Higuchi, K.; Maksyutov, S.

    2007-12-01

    Based on TransCom inverse modeling for 22 global regions, we developed a nested global inversion system for estimating carbon fluxes of 30 regions in North America (2 of the 22 regions are divided into 30). Irregular boundaries of these 30 regions are delineated based on ecosystem types and provincial/state borders. Synthesis Bayesian inversion is conducted in monthly steps using CO2 concentration measurements at 88 coastal and continental stations of the globe for the 1994-2003 period (NOAA GlobalView database). Responses of these stations to carbon fluxes from the 50 regions are simulated using the transport model of National Institute for Environmental Studies of Japan and reanalysis wind fields of the National Centers for Environmental Prediction (NCEP). Terrestrial carbon flux fields modeled using BEPS and Biome-BGC driven by NCEP reanalysis meteorological data are used as two different a priori to constrain the inversion. The inversion (top- down) results are compared with remote sensing-based ecosystem modeling (bottom-up) results in Canada's forests and wetlands. There is a broad consistency in the spatial pattern of the carbon source and sink distributions obtained using these two independent methods. Both sets of results also indicate that Canada's forests and wetlands are carbon sinks in 1994-2003, but the top-down method produces consistently larger sinks than the bottom-up results. Reasons for this discrepancy may lie in both methods, and several issues are identified for further investigation.

  9. How well do global ocean biogeochemistry models simulate dissolved iron distributions?

    Science.gov (United States)

    Tagliabue, Alessandro; Aumont, Olivier; DeAth, Ros; Dunne, John P.; Dutkiewicz, Stephanie; Galbraith, Eric; Misumi, Kazuhiro; Moore, J. Keith; Ridgwell, Andy; Sherman, Elliot; Stock, Charles; Vichi, Marcello; Völker, Christoph; Yool, Andrew

    2016-02-01

    Numerical models of ocean biogeochemistry are relied upon to make projections about the impact of climate change on marine resources and test hypotheses regarding the drivers of past changes in climate and ecosystems. In large areas of the ocean, iron availability regulates the functioning of marine ecosystems and hence the ocean carbon cycle. Accordingly, our ability to quantify the drivers and impacts of fluctuations in ocean ecosystems and carbon cycling in space and time relies on first achieving an appropriate representation of the modern marine iron cycle in models. When the iron distributions from 13 global ocean biogeochemistry models are compared against the latest oceanic sections from the GEOTRACES program, we find that all models struggle to reproduce many aspects of the observed spatial patterns. Models that reflect the emerging evidence for multiple iron sources or subtleties of its internal cycling perform much better in capturing observed features than their simpler contemporaries, particularly in the ocean interior. We show that the substantial uncertainty in the input fluxes of iron results in a very wide range of residence times across models, which has implications for the response of ecosystems and global carbon cycling to perturbations. Given this large uncertainty, iron fertilization experiments based on any single current generation model should be interpreted with caution. Improvements to how such models represent iron scavenging and also biological cycling are needed to raise confidence in their projections of global biogeochemical change in the ocean.

  10. Intermittently Closed/Open Lakes and Lagoons: Their global distribution and boundary conditions

    Science.gov (United States)

    McSweeney, S. L.; Kennedy, D. M.; Rutherfurd, I. D.; Stout, J. C.

    2017-09-01

    Intermittently Closed/Open Lakes and Lagoons (ICOLLs) are a particularly dynamic form of estuary characterised by periodic entrance closure to the ocean. Closure occurs when a subaerial sand berm stabilises across the entrance channel during times of low fluvial discharge. ICOLLs are of global importance as they provide valuable ecological habitats for many species and are associated with a wide range of management issues due to their cycle of entrance closure and opening. ICOLLs are found to be more widespread globally than previously described with 1477 of these estuaries being identified in this study. This constitutes an estimated 3% of the world's estuaries and 15% of all estuaries along microtidal coastlines. ICOLLs are concentrated along microtidal to low mesotidal coastlines in the mid-latitudes and predominantly on coasts with temperate climates. This distribution is related to greater wave heights as driven by high intensity winds and a longer fetch distance. The highest proportion of ICOLLs are present in Australia (21% all global ICOLLs), South Africa (16%) and Mexico (16%). In Australia, a comparison with fluvial input found that it is less important than marine processes in determining ICOLL formation and that ICOLLs are associated with a relative tidal range of systems with catchments < 2000 km2 and tidal prisms < 30 × 106 m3, forming at the mouths of rivers with generally low mean annual and specific discharges.

  11. Local and global genetic diversity of protozoan parasites: Spatial distribution of Cryptosporidium and Giardia genotypes.

    Science.gov (United States)

    Garcia-R, Juan C; French, Nigel; Pita, Anthony; Velathanthiri, Niluka; Shrestha, Rima; Hayman, David

    2017-07-01

    Cryptosporidiosis and giardiasis are recognized as significant enteric diseases due to their long-term health effects in humans and their economic impact in agriculture and medical care. Molecular analysis is essential to identify species and genotypes causing these infectious diseases and provides a potential tool for monitoring. This study uses information on species and genetic variants to gain insights into the geographical distribution and spatial patterns of Cryptosporidium and Giardia parasites. Here, we describe the population heterogeneity of genotypic groups within Cryptosporidium and Giardia present in New Zealand using gp60 and gdh markers to compare the observed variation with other countries around the globe. Four species of Cryptosporidium (C. hominis, C. parvum, C. cuniculus and C. erinacei) and one species of Giardia (G. intestinalis) were identified. These species have been reported worldwide and there are not unique Cryptosporidium gp60 subtype families and Giardia gdh assemblages in New Zealand, most likely due to high gene flow of historical and current human activity (travel and trade) and persistence of large host population sizes. The global analysis revealed that genetic variants of these pathogens are widely distributed. However, genetic variation is underestimated by data biases (e.g. neglected submission of sequences to genetic databases) and low sampling. New genotypes are likely to be discovered as sampling efforts increase according to accumulation prediction analyses, especially for C. parvum. Our study highlights the need for greater sampling and archiving of genotypes globally to allow comparative analyses that help understand the population dynamics of these protozoan parasites. Overall our study represents a comprehensive overview for exploring local and global protozoan genotype diversity and advances our understanding of the importance for surveillance and potential risk associated with these infectious diseases.

  12. Globalization

    Directory of Open Access Journals (Sweden)

    Tulio Rosembuj

    2006-12-01

    Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  13. A global distribution of the ignitability component of flammability based on climatic drivers

    Science.gov (United States)

    Karali, Anna; Fyllas, Nikolaos M.; Hatzaki, Maria; Giannakopoulos, Christos; Nastos, Panagiotis

    2017-04-01

    Fire regime is the result of complex interactions among ignition, topography, weather and vegetation. Even though the influence of vegetation varies regionally, it remains the only component that can be directly managed in order to reduce the negative impacts of wildland fires. Therefore, reliable information on vegetation flammability is required, making it one of the essential components of fire risk assessment and management. Specific Leaf Area (SLA [cm2 g-1], the ratio of leaf area to leaf dry mass) has received little attention regarding its relationship with ignitability and, thus, flammability. However, recent studies on a regional scale have shown that leaves of higher SLA are more ignitable. Thus, in the framework of the current study, the ignitability, as a function of SLA on global scale, is explored. In order to calculate SLA, a linear regression model combining SLA and climate data has been used (Maire et al., 2015). The climate data used for its calculation include the maximum monthly fractional sunshine duration, the maximum monthly temperature and the number of days with daily mean temperature above 0°C for each grid cell, obtained from the ERA-Interim gridded observations database. Subsequently, the ignitability component of flammability is calculated on a global scale using a bivariate regression relationship with SLA based on experimental burns of leaf materials (Grootemaat et al., 2015). The global distribution of ignitability can subsequently be combined with fire weather index (FWI) values for the development of an integrated index of forest fire vulnerability for the current and future climate, using CMIP5 climate model outputs. This will enable the integration of functional biogeographic data with widely applied fire risk assessment methodologies at regional to global spatial scales.

  14. Subnational distribution of average farm size and smallholder contributions to global food production

    Science.gov (United States)

    Samberg, Leah H.; Gerber, James S.; Ramankutty, Navin; Herrero, Mario; West, Paul C.

    2016-12-01

    Smallholder farming is the most prevalent form of agriculture in the world, supports many of the planet’s most vulnerable populations, and coexists with some of its most diverse and threatened landscapes. However, there is little information about the location of small farms, making it difficult both to estimate their numbers and to implement effective agricultural, development, and land use policies. Here, we present a map of mean agricultural area, classified by the amount of land per farming household, at subnational resolutions across three key global regions using a novel integration of household microdata and agricultural landscape data. This approach provides a subnational estimate of the number, average size, and contribution of farms across much of the developing world. By our estimates, 918 subnational units in 83 countries in Latin America, sub-Saharan Africa, and South and East Asia average less than five hectares of agricultural land per farming household. These smallholder-dominated systems are home to more than 380 million farming households, make up roughly 30% of the agricultural land and produce more than 70% of the food calories produced in these regions, and are responsible for more than half of the food calories produced globally, as well as more than half of global production of several major food crops. Smallholder systems in these three regions direct a greater percentage of calories produced toward direct human consumption, with 70% of calories produced in these units consumed as food, compared to 55% globally. Our approach provides the ability to disaggregate farming populations from non-farming populations, providing a more accurate picture of farming households on the landscape than has previously been available. These data meet a critical need, as improved understanding of the prevalence and distribution of smallholder farming is essential for effective policy development for food security, poverty reduction, and conservation agendas.

  15. Temperature drives global patterns in forest biomass distribution in leaves, stems, and roots

    Science.gov (United States)

    Reich, Peter B.; Lou, Yunjian; Bradford, John B.; Poorter, Hendrik; Perry, Charles H.; Oleksyn, Jacek

    2014-01-01

    Whether the fraction of total forest biomass distributed in roots, stems, or leaves varies systematically across geographic gradients remains unknown despite its importance for understanding forest ecology and modeling global carbon cycles. It has been hypothesized that plants should maintain proportionally more biomass in the organ that acquires the most limiting resource. Accordingly, we hypothesize greater biomass distribution in roots and less in stems and foliage in increasingly arid climates and in colder environments at high latitudes. Such a strategy would increase uptake of soil water in dry conditions and of soil nutrients in cold soils, where they are at low supply and are less mobile. We use a large global biomass dataset (>6,200 forests from 61 countries, across a 40 °C gradient in mean annual temperature) to address these questions. Climate metrics involving temperature were better predictors of biomass partitioning than those involving moisture availability, because, surprisingly, fractional distribution of biomass to roots or foliage was unrelated to aridity. In contrast, in increasingly cold climates, the proportion of total forest biomass in roots was greater and in foliage was smaller for both angiosperm and gymnosperm forests. These findings support hypotheses about adaptive strategies of forest trees to temperature and provide biogeographically explicit relationships to improve ecosystem and earth system models. They also will allow, for the first time to our knowledge, representations of root carbon pools that consider biogeographic differences, which are useful for quantifying whole-ecosystem carbon stocks and cycles and for assessing the impact of climate change on forest carbon dynamics.

  16. Global distribution and sources of dissolved inorganic nitrogen export to the coastal zone: Results from a spatially explicit, global model

    NARCIS (Netherlands)

    Dumont, E.L.; Harrison, J.A.; Kroeze, C.; Bakker, E.J.; Seitzinger, S.P.

    2005-01-01

    Here we describe, test, and apply a spatially explicit, global model for predicting dissolved inorganic nitrogen (DIN) export by rivers to coastal waters (NEWS-DIN). NEWS-DIN was developed as part of an internally consistent suite of global nutrient export models. Modeled and measured DIN export

  17. Multistage and multiobjective formulations of globally optimal upgradable expansions for electric power distribution systems

    Science.gov (United States)

    Vaziri Yazdi Pin, Mohammad

    Electric power distribution systems are the last high voltage link in the chain of production, transport, and delivery of the electric energy, the fundamental goals of which are to supply the users' demand safely, reliably, and economically. The number circuit miles traversed by distribution feeders in the form of visible overhead or imbedded underground lines, far exceed those of all other bulk transport circuitry in the transmission system. Development and expansion of the distribution systems, similar to other systems, is directly proportional to the growth in demand and requires careful planning. While growth of electric demand has recently slowed through efforts in the area of energy management, the need for a continued expansion seems inevitable for the near future. Distribution system and expansions are also independent of current issues facing both the suppliers and the consumers of electrical energy. For example, deregulation, as an attempt to promote competition by giving more choices to the consumers, while it will impact the suppliers' planning strategies, it cannot limit the demand growth or the system expansion in the global sense. Curiously, despite presence of technological advancements and a 40-year history of contributions in the area, many of the major utilities still relay on experience and resort to rudimentary techniques when planning expansions. A comprehensive literature review of the contributions and careful analyses of the proposed algorithms for distribution expansion, confirmed that the problem is a complex, multistage and multiobjective problem for which a practical solution remains to be developed. In this research, based on the 15-year experience of a utility engineer, the practical expansion problem has been clearly defined and the existing deficiencies in the previous work identified and analyzed. The expansion problem has been formulated as a multistage planning problem in line with a natural course of development and industry

  18. Economic and physical determinants of the global distributions of crop pests and pathogens.

    Science.gov (United States)

    Bebber, Daniel P; Holmes, Timothy; Smith, David; Gurr, Sarah J

    2014-05-01

    Crop pests and pathogens pose a significant and growing threat to food security, but their geographical distributions are poorly understood. We present a global analysis of pest and pathogen distributions, to determine the roles of socioeconomic and biophysical factors in determining pest diversity, controlling for variation in observational capacity among countries. Known distributions of 1901 pests and pathogens were obtained from CABI. Linear models were used to partition the variation in pest species per country amongst predictors. Reported pest numbers increased with per capita gross domestic product (GDP), research expenditure and research capacity, and the influence of economics was greater in micro-organisms than in arthropods. Total crop production and crop diversity were the strongest physical predictors of pest numbers per country, but trade and tourism were insignificant once other factors were controlled. Islands reported more pests than mainland countries, but no latitudinal gradient in species richness was evident. Country wealth is likely to be a strong indicator of observational capacity, not just trade flow, as has been interpreted in invasive species studies. If every country had US levels of per capita GDP, then 205 ± 9 additional pests per country would be reported, suggesting that enhanced investment in pest observations will reveal the hidden threat of crop pests and pathogens. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  19. Global distributions of water vapour isotopologues retrieved from IMG/ADEOS data

    Directory of Open Access Journals (Sweden)

    H. Herbin

    2007-07-01

    Full Text Available The isotopologic composition of water vapour in the atmosphere provides valuable information on many climate, chemical and dynamical processes. The accurate measurements of the water isotopologues by remote-sensing techniques remains a challenge, due to the large spatial and temporal variations. Simultaneous profile retrievals of the main water isotopologues (i.e. H216O, H218O and HDO and their ratios are presented here for the first time, along their retrieved global distributions. The results are obtained by exploiting the high resolution infrared spectra recorded by the Interferometric Monitor for Greenhouse gases (IMG instrument, which has operated in the nadir geometry onboard the ADEOS satellite between 1996 and 1997. The retrievals are performed on cloud-free radiances, measured during ten days of April 1997, considering two atmospheric windows (1205–1228 cm−1; 2004–2032 cm−1 and using a line-by-line radiative transfer model and an inversion procedure based on the Optimal Estimation Method (OEM. Characterizations in terms of vertical sensitivity and error budget are provided. We show that a relatively high vertical resolution is achieved for H216O (~4–5 km, and that the retrieved profiles are in fair agreement with local sonde measurements, at different latitudes. The retrieved global distributions of H216O, H218O, HDO and their ratios are presented and found to be consistent with previous experimental studies and models. The Ocean-Continent difference, the latitudinal and vertical dependence of the water vapour amount and the isotopologic depletion are notably well reproduced. Others trends, possibly related to small-scale variations in the vertical profiles are also discussed. Despite the difficulties encountered for computing accurately the isotopologic ratios, our results demonstrate the ability

  20. Global distribution, diversity hot spots and niche transitions of an astaxanthin-producing eukaryotic microbe.

    Science.gov (United States)

    David-Palma, Márcia; Libkind, Diego; Sampaio, José Paulo

    2014-02-01

    Microbes establish very diverse but still poorly understood associations with other microscopic or macroscopic organisms that do not follow the more conventional modes of competition or mutualism. Phaffia rhodozyma, an orange-coloured yeast that produces the biotechnologically relevant carotenoid astaxanthin, exhibits a Holarctic association with birch trees in temperate forests that contrasts with the more recent finding of a South American population associated with Nothofagus (southern beech) and with stromata of its biotrophic fungal parasite Cyttaria spp. We investigated whether the association of Phaffia with Nothofagus-Cyttaria could be expanded to Australasia, the other region of the world where Nothofagus are endemic, studied the genetic structure of populations representing the known worldwide distribution of Phaffia and analysed the evolution of the association with tree hosts. The phylogenetic analysis revealed that Phaffia diversity in Australasia is much higher than in other regions of the globe and that two endemic and markedly divergent lineages seem to represent new species. The observed genetic diversity correlates with host tree genera rather than with geography, which suggests that adaptation to the different niches is driving population structure in this yeast. The high genetic diversity and endemism in Australasia indicate that the genus evolved in this region and that the association with Nothofagus is the ancestral tree association. Estimates of the divergence times of Phaffia lineages point to splits that are much more recent than the break-up of Gondwana, supporting that long-distance dispersal rather than vicariance is responsible for observed distribution of P. rhodozyma. © 2014 John Wiley & Sons Ltd.

  1. Inferential monitoring of global change impact on biodiversity through remote sensing and species distribution modeling

    Science.gov (United States)

    Sangermano, Florencia

    2009-12-01

    The world is suffering from rapid changes in both climate and land cover which are the main factors affecting global biodiversity. These changes may affect ecosystems by altering species distributions, population sizes, and community compositions, which emphasizes the need for a rapid assessment of biodiversity status for conservation and management purposes. Current approaches on monitoring biodiversity rely mainly on long term observations of predetermined sites, which require large amounts of time, money and personnel to be executed. In order to overcome problems associated with current field monitoring methods, the main objective of this dissertation is the development of framework for inferential monitoring of the impact of global change on biodiversity based on remotely sensed data coupled with species distribution modeling techniques. Several research pieces were performed independently in order to fulfill this goal. First, species distribution modeling was used to identify the ranges of 6362 birds, mammals and amphibians in South America. Chapter 1 compares the power of different presence-only species distribution methods for modeling distributions of species with different response curves to environmental gradients and sample sizes. It was found that there is large variability in the power of the methods for modeling habitat suitability and species ranges, showing the importance of performing, when possible, a preliminary gradient analysis of the species distribution before selecting the method to be used. Chapter 2 presents a new methodology for the redefinition of species range polygons. Using a method capable of establishing the uncertainty in the definition of existing range polygons, the automated procedure identifies the relative importance of bioclimatic variables for the species, predicts their ranges and generates a quality assessment report to explore prediction errors. Analysis using independent validation data shows the power of this

  2. Innovation in globally distributed teams: the role of LMX, communication frequency, and member influence on team decisions.

    Science.gov (United States)

    Gajendran, Ravi S; Joshi, Aparna

    2012-11-01

    For globally distributed teams charged with innovation, member contributions to the team are crucial for effective performance. Prior research, however, suggests that members of globally distributed teams often feel isolated and excluded from their team's activities and decisions. How can leaders of such teams foster member inclusion in team decisions? Drawing on leader-member exchange (LMX) theory, we propose that for distributed teams, LMX and communication frequency jointly shape member influence on team decisions. Findings from a test of our hypotheses using data from 40 globally distributed teams suggest that LMX can enhance member influence on team decisions when it is sustained through frequent leader-member communication. This joint effect is strengthened as team dispersion increases. At the team level, member influence on team decisions has a positive effect on team innovation. (c) 2012 APA, all rights reserved.

  3. The global distribution of thermospheric odd nitrogen for solstice conditions during solar cycle minimum

    Science.gov (United States)

    Gerard, J.-C.; Roble, R. G.; Rusch, D. W.; Stewart, A. I.

    1984-01-01

    A two-dimensional model of odd nitrogen in the thermosphere and upper mesosphere is described. The global distributions of nitric oxide and atomic nitrogen are calculated for the solstice period for quiet and moderate magnetic activity during the solar minimum period. The effect of thermospheric transport by winds is investigated along with the importance of particle-induced ionization in the auroral zones. The results are compared with rocket and satellite measurements, and the sensitivity of the model to eddy diffusion and neutral winds is investigated. Downward fluxes of NO into the mesosphere are given, and their importance for stratospheric ozone is discussed. The results show that the summer-to-winter pole meridional circulation transports both NO and N(S-4) across the solar terminator into the polar night region where there is a downward vertical transport toward the mesosphere. The model shows that odd nitrogen densities at high winter latitudes are entirely controlled by particle precipitation and transport processes.

  4. Global distribution of Chelonid fibropapilloma-associated herpesvirus among clinically healthy sea turtles

    DEFF Research Database (Denmark)

    Alfaro Nuñez, Luis Alonso; Bertelsen, Mads Frost; Bojesen, Anders Miki

    2014-01-01

    BackgroundFibropapillomatosis (FP) is a neoplastic disease characterized by cutaneous tumours that has been documented to infect all sea turtle species. Chelonid fibropapilloma-associated herpesvirus (CFPHV) is believed to be the aetiological agent of FP, based principally on consistent PCR...... clinically healthy individual sea turtles; representing four other species were also screened.ResultsCFPHV DNA sequences were obtained from 37/37 (100%) FP exhibiting green turtles, and 45/300 (15%) clinically healthy animals spanning all five species. Although the frequency of infected individuals per...... for two of the markers (UL18 and UL22) in turtles from Turks and Caicos separate to all others, regardless of host species or geographic origin.ConclusionPresence of CFPHV DNA within globally distributed samples for all five species of sea turtle was confirmed. While 100% of the FP exhibiting green...

  5. Fast distributed strategic learning for global optima in queueing access games

    KAUST Repository

    Tembine, Hamidou

    2014-08-24

    In this paper we examine combined fully distributed payoff and strategy learning (CODIPAS) in a queue-aware access game over a graph. The classical strategic learning analysis relies on vanishing or small learning rate and uses stochastic approximation tool to derive steady states and invariant sets of the underlying learning process. Here, the stochastic approximation framework does not apply due to non-vanishing learning rate. We propose a direct proof of convergence of the process. Interestingly, the convergence time to one of the global optima is almost surely finite and we explicitly characterize the convergence time. We show that pursuit-based CODIPAS learning is much faster than the classical learning algorithms in games. We extend the methodology to coalitional learning and proves a very fast formation of coalitions for queue-aware access games where the action space is dynamically changing depending on the location of the user over a graph.

  6. Global distribution of total cloud cover and cloud type amounts over the ocean

    Energy Technology Data Exchange (ETDEWEB)

    Warren, S.G.; Hahn, C.J.; London, J.; Chervin, R.M.; Jenne, R.L. (Washington Univ., Seattle, WA (USA). Dept. of Atmospheric Sciences; Colorado Univ., Boulder, CO (USA). Cooperative Inst. for Research in Environmental Sciences; Colorado Univ., Boulder, CO (USA). Dept. of Astrophysical, Planetary, and Atmospheric Sciences; National Center for Atmospheric Research, Boulder, CO (USA))

    1988-12-01

    This is the fourth of a series of atlases to result from a study of the global cloud distribution from ground-based observations. The first two atlases (NCAR/TN-201+STR and NCAR/TN-241+STR) described the frequency of occurrence of each cloud type and the co-occurrence of different types, but included no information about cloud amounts. The third atlas (NCAR/TN-273+STR) described, for the land areas of the earth, the average total cloud cover and the amounts of each cloud type, and their geographical, diurnal, seasonal, and interannual variations, as well as the average base heights of the low clouds. The present atlas does the same for the ocean areas of the earth.

  7. Insights into global diatom distribution and diversity in the world’s ocean

    KAUST Repository

    Malviya, Shruti

    2016-03-01

    Diatoms (Bacillariophyta) constitute one of the most diverse and ecologically important groups of phytoplankton. They are considered to be particularly important in nutrient-rich coastal ecosystems and at high latitudes, but considerably less so in the oligotrophic open ocean. The Tara Oceans circumnavigation collected samples from a wide range of oceanic regions using a standardized sampling procedure. Here, a total of ∼12 million diatom V9-18S ribosomal DNA (rDNA) ribotypes, derived from 293 sizefractionated plankton communities collected at 46 sampling sites across the global ocean euphotic zone, have been analyzed to explore diatom global diversity and community composition. We provide a new estimate of diversity of marine planktonic diatoms at 4,748 operational taxonomic units (OTUs). Based on the total assigned ribotypes, Chaetoceros was the most abundant and diverse genus, followed by Fragilariopsis, Thalassiosira, and Corethron. We found only a few cosmopolitan ribotypes displaying an even distribution across stations and high abundance, many of which could not be assigned with confidence to any known genus. Three distinct communities from South Pacific, Mediterranean, and Southern Ocean waters were identified that share a substantial percentage of ribotypes within them. Sudden drops in diversity were observed at Cape Agulhas, which separates the Indian and Atlantic Oceans, and across the Drake Passage between the Atlantic and Southern Oceans, indicating the importance of these ocean circulation choke points in constraining diatom distribution and diversity. We also observed high diatom diversity in the open ocean, suggesting that diatoms may be more relevant in these oceanic systems than generally considered.

  8. Predicting potential global distributions of two Miscanthus grasses: implications for horticulture, biofuel production, and biological invasions.

    Science.gov (United States)

    Hager, Heather A; Sinasac, Sarah E; Gedalof, Ze'ev; Newman, Jonathan A

    2014-01-01

    In many regions, large proportions of the naturalized and invasive non-native floras were originally introduced deliberately by humans. Pest risk assessments are now used in many jurisdictions to regulate the importation of species and usually include an estimation of the potential distribution in the import area. Two species of Asian grass (Miscanthus sacchariflorus and M. sinensis) that were originally introduced to North America as ornamental plants have since escaped cultivation. These species and their hybrid offspring are now receiving attention for large-scale production as biofuel crops in North America and elsewhere. We evaluated their potential global climate suitability for cultivation and potential invasion using the niche model CLIMEX and evaluated the models' sensitivity to the parameter values. We then compared the sensitivity of projections of future climatically suitable area under two climate models and two emissions scenarios. The models indicate that the species have been introduced to most of the potential global climatically suitable areas in the northern but not the southern hemisphere. The more narrowly distributed species (M. sacchariflorus) is more sensitive to changes in model parameters, which could have implications for modelling species of conservation concern. Climate projections indicate likely contractions in potential range in the south, but expansions in the north, particularly in introduced areas where biomass production trials are under way. Climate sensitivity analysis shows that projections differ more between the selected climate change models than between the selected emissions scenarios. Local-scale assessments are required to overlay suitable habitat with climate projections to estimate areas of cultivation potential and invasion risk.

  9. On the Global Water Productivity Distribution for Major Cereal Crops: some First Results from Satellite Measurements

    Science.gov (United States)

    Bastiaanssen, W. G.; Verstegen, J. A.; Steduto, P.; Goudriaan, R.; Wada, Y.

    2014-12-01

    Feeding the world requires 70 percent more food for an additional 2.3 billion people by 2050. The increasing competition for water resources prompts the modern consumer society to become more efficient with scarce water resources. The water footprint of agriculture is hundred times more than the footprint for domestic water use, yet we do not fully know how much water is used in relation to the amount of food being produced. Water Productivity describes the crop yield per unit of water consumed and is the ultimate indicator for the efficiency of water use in agriculture. Our basic understanding of actual and benchmark values for Water Productivity is limited, partially because operational measurements and guidelines for Water Productivity do not currently exist. Remote sensing algorithms have been developed over the last 20 years to compute crop yield Y and evapotranspiration ET, often in an independent manner. The new WatPro and GlobWat algorithms are based on directly solving the Y/ET ratio. Several biophysical parameter and processes such as solar radiation, Leaf Area Index, stomatal aperture and soil moisture affect biomass production and crop transpiration simultaneously, and this enabled us to simplify the schematization of a Y/ET model. Global maps of wheat, rice and maize were prepared from various open-access data sources, and Y/ET was computed across a period of 10 years. The global distribution demonstrates that 66 percent of the world's agricultural land cultivated with wheat, rice and corn performs below average. Furthermore, Water Productivity in most countries exhibits a significant spatial variability. Therefore, there is significant scope to produce the same food - or more food - from less water resources if packages with good practices are locally implemented. The global maps of water productivity will be demonstrated, along with some country examples.

  10. The global landslide distribution in the 2015-16 El Nino event

    Science.gov (United States)

    Petley, D. N.; Froude, M.

    2016-12-01

    It is commonly perceived that the global landslide distribution is heavily influenced by the El Nino / La Nina cycle, and that strong El Nino events are associated with a higher than average occurrence of landslides in many areas. Thus, for example, the very intense 1997-98 El Nino event coincided with high incidence of landslides in parts of North America and South America, and elsewhere. However, there is comparatively little systematic analysis on a global basis. The 2015-16 El Nino event was the most intense since 1997-98, and had been anticipated to generate significant landslide impacts. The occurrence of landslides worldwide through the 2015-16 El Nino has been examined using the author's landslide fatality database, which has been compiled since 2002. The data indicates that 2015 was a year with an unusually small number of rainfall-induced landslides, significantly below the long term average and with unusually low consequences. This is primarily because of two key factors: first, the South Asian monsoon was anomalously weak, resulting in low landslide impacts in the Himalayas. Second, the occurrence of intense landfalling tropical cyclones across East Asia was also unusually low. The combined effect of these two sets of meteorological conditions was low landslide occurrence across Asia. Landslide occurrence across the Americas was also low. On the other hand, 2016 is proving to be an unusually intense landslide year. In particular, intense rainfall associated with early part of the South Asian monsoon has resulted in very widespread landsliding across South Asia. This paper examines the lessons that can be learnt from an improved understanding the relationship between El Nino events and global landslide impacts, and reflects upon the capability to anticipate the impacts of future large El Nino events.

  11. Unbiased global determination of parton distributions and their uncertainties at NNLO and at LO

    Energy Technology Data Exchange (ETDEWEB)

    Ball, Richard D. [Tait Institute, University of Edinburgh, JCMB, KB, Mayfield Rd, Edinburgh EH9 3JZ, Scotland (United Kingdom); Niels Bohr International Academy and Discovery Center, The Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); Bertone, Valerio [Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder-Strasse 3, D-79104 Freiburg i. B. (Germany); Cerutti, Francesco [Departament d' Estructura i Constituents de la Materia, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Del Debbio, Luigi [Tait Institute, University of Edinburgh, JCMB, KB, Mayfield Rd, Edinburgh EH9 3JZ, Scotland (United Kingdom); Forte, Stefano, E-mail: forte@mi.infn.it [Dipartimento di Fisica, Universita di Milano and INFN, Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Guffanti, Alberto [Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder-Strasse 3, D-79104 Freiburg i. B. (Germany); The Niels Bohr International Academy and Discovery Center, The Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); Latorre, Jose I. [Departament d' Estructura i Constituents de la Materia, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Rojo, Juan [Dipartimento di Fisica, Universita di Milano and INFN, Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Ubiali, Maria [Institut fuer Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen (Germany)

    2012-02-11

    We present a determination of the parton distributions of the nucleon from a global set of hard scattering data using the NNPDF methodology at LO and NNLO in perturbative QCD, thereby generalizing to these orders the NNPDF2.1 NLO parton set. Heavy quark masses are included using the so-called FONLL method, which is benchmarked here at NNLO. We demonstrate the stability of PDFs upon inclusion of NNLO corrections, and we investigate the convergence of the perturbative expansion by comparing LO, NLO and NNLO results. We show that the momentum sum rule can be tested with increasing accuracy at LO, NLO and NNLO. We discuss the impact of NNLO corrections on collider phenomenology, specifically by comparing to recent LHC data. We present PDF determinations using a range of values of {alpha}{sub s}, m{sub c} and m{sub b}. We also present PDF determinations based on various subsets of the global dataset, show that they generally lead to less accurate phenomenology, and discuss the possibility of future PDF determinations based on collider data only.

  12. Global distribution of minerals in arid soils as lower boundary condition in dust models

    Science.gov (United States)

    Nickovic, Slobodan

    2010-05-01

    Mineral dust eroded from arid soils affects the radiation budget of the Earth system, modifies ocean bioproductivity and influences human health. Dust aerosol is a complex mixture of minerals. Dust mineral composition has several potentially important impacts to environment and society. Iron and phosphorus embedded in mineral aerosol are essential for the primary marine productivity when dust deposits over the open ocean. Dust also acts as efficient agent for heterogeneous ice nucleation and this process is dependent on mineralogical structure of dust. Recent findings in medical geology indicate possible role of minerals to human health. In this study, a new 1-km global database was developed for several minerals (Illite, Kaolinite, Smectite, Calcite, Quartz, Feldspar, Hematite and Gypsum) embedded in clay and silt populations of arid soils. For the database generation, high-resolution data sets on soil textures, soil types and land cover was used. Tin addition to the selected minerals, phosphorus was also added whose geographical distribution was specified from compiled literature and data on soil types. The developed global database was used to specify sources of mineral fractions in the DREAM dust model and to simulate atmospheric paths of minerals and their potential impacts on marine biochemistry and tropospheric ice nucleation.

  13. Global population structure of the spiny dogfish Squalus acanthias, a temperate shark with an antitropical distribution.

    Science.gov (United States)

    Veríssimo, A; McDowell, J R; Graves, J E

    2010-04-01

    The spiny dogfish (Squalus acanthias) is a temperate, coastal squaloid shark with an antitropical distribution in the Atlantic and Pacific oceans. The global population structure of this species is poorly understood, although individuals are known to undergo extensive migrations within coastal waters and across ocean basins. In this study, an analysis of the global population structure of the spiny dogfish was conducted using eight polymorphic nuclear microsatellite markers and a 566-bp fragment of the mitochondrial ND2 gene region. A low level of genetic divergence was found among collections from the Atlantic and South Pacific basins, whereas a high level of genetic divergence was found among Pacific Ocean collections. Two genetically distinct groups were recovered by both marker classes: one exclusive to North Pacific collections, and one including collections from the South Pacific and Atlantic locations. The strong genetic break across the equatorial Pacific coincides with major regional differences in the life-history characters of spiny dogfish, suggesting that spiny dogfish in areas on either side of the Pacific equator have been evolving independently for a considerable time. Phylogeographic analyses indicate that spiny dogfish populations had a Pacific origin, and that the North Atlantic was colonized as a result of a recent range expansion from the South American coast. Finally, the available data strongly argue for the taxonomic separation of the North Pacific spiny dogfish from S. acanthias and a re-evaluation of the specific status of S. acanthias is warranted.

  14. Global distribution of winter lightning: a threat to wind turbines and aircraft

    Science.gov (United States)

    Montanyà, Joan; Fabró, Ferran; van der Velde, Oscar; March, Víctor; Rolfe Williams, Earle; Pineda, Nicolau; Romero, David; Solà, Glòria; Freijo, Modesto

    2016-06-01

    Lightning is one of the major threats to multi-megawatt wind turbines and a concern for modern aircraft due to the use of lightweight composite materials. Both wind turbines and aircraft can initiate lightning, and very favorable conditions for lightning initiation occur in winter thunderstorms. Moreover, winter thunderstorms are characterized by a relatively high production of very energetic lightning. This paper reviews the different types of lightning interactions and summarizes the well-known winter thunderstorm areas. Until now comprehensive maps of global distribution of winter lightning prevalence to be used for risk assessment have been unavailable. In this paper we present the global winter lightning activity for a period of 5 years. Using lightning location data and meteorological re-analysis data, six maps are created: annual winter lightning stroke density, seasonal variation of the winter lightning and the annual number of winter thunderstorm days. In the Northern Hemisphere, the maps confirmed Japan to be one of the most active regions but other areas such as the Mediterranean and the USA are active as well. In the Southern Hemisphere, Uruguay and surrounding area, the southwestern Indian Ocean and the Tasman Sea experience the highest activity. The maps provided here can be used in the development of a risk assessment.

  15. Physiological constraints on the global distribution of Trichodesmium – effect of temperature on diazotrophy

    Directory of Open Access Journals (Sweden)

    E. Breitbarth

    2007-01-01

    Full Text Available The cyanobacterium Trichodesmium is an important link in the global nitrogen cycle due to its significant input of atmospheric nitrogen to the ocean. Attempts to incorporate Trichodesmium in ocean biogeochemical circulation models have, so far, relied on the observed correlation between temperature and Trichodesmium abundance. This correlation may result in part from a direct effect of temperature on Trichodesmium growth rates through the control of cellular biochemical processes, or indirectly through temperature influence on mixed layer depth, light and nutrient regimes. Here we present results indicating that the observed correlation of Trichodesmium with temperature in the field reflects primarily the direct physiological effects of temperature on diazotrophic growth of Trichodesmium. Trichodesmium IMS-101 (an isolate of Trichodesmium could acclimate and grow at temperatures ranging from 20 to 34°C. Maximum growth rates (μmax=0.25 day–1 and maximum nitrogen fixation rates (0.13 mmol N mol POC−1 h–1 were measured within 24 to 30°C. Combining this empirical relationship with global warming scenarios derived from state-of-the-art climate models sets a physiological constraint on the future distribution of Trichodesmium that could significantly affect the future nitrogen input into oligotrophic waters by this diazotroph.

  16. Distribution and Validation of CERES Irradiance Global Data Products Via Web Based Tools

    Science.gov (United States)

    Rutan, David; Mitrescu, Cristian; Doelling, David; Kato, Seiji

    2016-01-01

    The CERES SYN1deg product provides climate quality 3-hourly globally gridded and temporally complete maps of top of atmosphere, in atmosphere, and surface fluxes. This product requires efficient release to the public and validation to maintain quality assurance. The CERES team developed web-tools for the distribution of both the global gridded products and grid boxes that contain long term validation sites that maintain high quality flux observations at the Earth's surface. These are found at: http://ceres.larc.nasa.gov/order_data.php. In this poster we explore the various tools available to users to sub-set, download, and validate using surface observations the SYN1Deg and Surface-EBAF products. We also analyze differences found in long-term records from well-maintained land surface sites such as the ARM central facility and high quality buoy radiometers, which due to their isolated nature cannot be maintained in a similar manner to their land based counterparts.

  17. Ecological consequences of human niche construction: Examining long-term anthropogenic shaping of global species distributions

    Science.gov (United States)

    Boivin, Nicole L.; Zeder, Melinda A.; Fuller, Dorian Q.; Crowther, Alison; Larson, Greger; Erlandson, Jon M.; Denham, Tim; Petraglia, Michael D.

    2016-01-01

    The exhibition of increasingly intensive and complex niche construction behaviors through time is a key feature of human evolution, culminating in the advanced capacity for ecosystem engineering exhibited by Homo sapiens. A crucial outcome of such behaviors has been the dramatic reshaping of the global biosphere, a transformation whose early origins are increasingly apparent from cumulative archaeological and paleoecological datasets. Such data suggest that, by the Late Pleistocene, humans had begun to engage in activities that have led to alterations in the distributions of a vast array of species across most, if not all, taxonomic groups. Changes to biodiversity have included extinctions, extirpations, and shifts in species composition, diversity, and community structure. We outline key examples of these changes, highlighting findings from the study of new datasets, like ancient DNA (aDNA), stable isotopes, and microfossils, as well as the application of new statistical and computational methods to datasets that have accumulated significantly in recent decades. We focus on four major phases that witnessed broad anthropogenic alterations to biodiversity—the Late Pleistocene global human expansion, the Neolithic spread of agriculture, the era of island colonization, and the emergence of early urbanized societies and commercial networks. Archaeological evidence documents millennia of anthropogenic transformations that have created novel ecosystems around the world. This record has implications for ecological and evolutionary research, conservation strategies, and the maintenance of ecosystem services, pointing to a significant need for broader cross-disciplinary engagement between archaeology and the biological and environmental sciences. PMID:27274046

  18. Global distribution of Chelonid fibropapilloma-associated herpesvirus among clinically healthy sea turtles.

    Science.gov (United States)

    Alfaro-Núñez, Alonzo; Frost Bertelsen, Mads; Bojesen, Anders Miki; Rasmussen, Isabel; Zepeda-Mendoza, Lisandra; Tange Olsen, Morten; Gilbert, Marcus Thomas Pius

    2014-10-25

    Fibropapillomatosis (FP) is a neoplastic disease characterized by cutaneous tumours that has been documented to infect all sea turtle species. Chelonid fibropapilloma-associated herpesvirus (CFPHV) is believed to be the aetiological agent of FP, based principally on consistent PCR-based detection of herpesvirus DNA sequences from FP tumours. We used a recently described PCR-based assay that targets 3 conserved CFPHV genes, to survey 208 green turtles (Chelonia mydas). This included both FP tumour exhibiting and clinically healthy individuals. An additional 129 globally distributed clinically healthy individual sea turtles; representing four other species were also screened. CFPHV DNA sequences were obtained from 37/37 (100%) FP exhibiting green turtles, and 45/300 (15%) clinically healthy animals spanning all five species. Although the frequency of infected individuals per turtle population varied considerably, most global populations contained at least one CFPHV positive individual, with the exception of various turtle species from the Arabian Gulf, Northern Indian Ocean and Puerto Rico. Haplotype analysis of the different gene markers clustered the CFPHV DNA sequences for two of the markers (UL18 and UL22) in turtles from Turks and Caicos separate to all others, regardless of host species or geographic origin. Presence of CFPHV DNA within globally distributed samples for all five species of sea turtle was confirmed. While 100% of the FP exhibiting green turtles yielded CFPHV sequences, surprisingly, so did 15% of the clinically healthy turtles. We hypothesize that turtle populations with zero (0%) CFPHV frequency may be attributed to possible environmental differences, diet and/or genetic resistance in these individuals. Our results provide first data on the prevalence of CFPHV among seemingly healthy turtles; a factor that may not be directly correlated to the disease incidence, but may suggest of a long-term co-evolutionary latent infection interaction between

  19. Continuous gene flow contributes to low global species abundance and distribution of a marine model diatom

    KAUST Repository

    Rastogi, Achal

    2017-08-15

    Unlike terrestrial ecosystems where geographical isolation often leads to a restricted gene flow between species, genetic admixing in aquatic micro-eukaryotes is likely to be frequent. Diatoms inhabit marine ecosystems since the Mesozoic period and presently constitute one of the major primary producers in the world ocean. They are a highly diversified group of eukaryotic phytoplankton with estimates of up to 200,000 species. Since decades, Phaeodactylum tricornutum is used as a model diatom species to characterize the functional pathways, physiology and evolution of diatoms in general. In the current study, using whole genome sequencing of ten P. tricornutum strains, sampled at broad geospatial and temporal scales, we show a continuous dispersal and genetic admixing between geographically isolated strains. We also describe a very high level of heterozygosity and propose it to be a consequence of frequent ancestral admixture. Our finding that P. tricornutum sequences are plausibly detectable at low but broadly distributed levels in the world ocean further suggests that high admixing between geographically isolated strains may create a significant bottleneck, thus influencing their global abundance and distribution in nature. Finally, in an attempt to understand the functional implications of genetic diversity between different P. tricornutum ecotypes, we show the effects of domestication in inducing changes in the selection pressure on many genes and metabolic pathways. We propose these findings to have significant implications for understanding the genetic structure of diatom populations in nature and provide a framework to assess the genomic underpinnings of their ecological success.

  20. Fruiting Season Length Restricts Global Distribution of Female-Only Parental Care in Frugivorous Passerine Birds.

    Science.gov (United States)

    Barve, Sahas; La Sorte, Frank A

    2016-01-01

    Food availability is known to influence parental care and mating systems in passerine birds. Altricial chicks make uni-parental care particularly demanding for passerines and parental investment is known to increase with decreasing food availability. We expect this to limit uni-parental passerines to habitats with the most consistent food availability. In passerine birds, species having uni-parental care are primarily female-only parental care (female-only care) and most passerine birds with female-only care are frugivores. We predict that frugivorous passerines with female-only care should be restricted to the most stable habitats characterized by longer fruiting season length. At a global scale, female-only care frugivores were distributed in areas with significantly longer fruiting seasons than non-female-only care frugivores. Female-only care species richness had a stronger spatial relationship with longer fruiting season than non-female-only care species richness. Verifying the lack of a phylogenetic signal driving this pattern, our findings indicate that the geographic distribution of female-only care, a geographically and phylogenetically widespread parental care system, is restricted by an extrinsic factor: fruiting season length. This reinstates the importance of food availability on the evolution and maintenance of parental care systems in passerine birds.

  1. Fruiting Season Length Restricts Global Distribution of Female-Only Parental Care in Frugivorous Passerine Birds.

    Directory of Open Access Journals (Sweden)

    Sahas Barve

    Full Text Available Food availability is known to influence parental care and mating systems in passerine birds. Altricial chicks make uni-parental care particularly demanding for passerines and parental investment is known to increase with decreasing food availability. We expect this to limit uni-parental passerines to habitats with the most consistent food availability. In passerine birds, species having uni-parental care are primarily female-only parental care (female-only care and most passerine birds with female-only care are frugivores. We predict that frugivorous passerines with female-only care should be restricted to the most stable habitats characterized by longer fruiting season length. At a global scale, female-only care frugivores were distributed in areas with significantly longer fruiting seasons than non-female-only care frugivores. Female-only care species richness had a stronger spatial relationship with longer fruiting season than non-female-only care species richness. Verifying the lack of a phylogenetic signal driving this pattern, our findings indicate that the geographic distribution of female-only care, a geographically and phylogenetically widespread parental care system, is restricted by an extrinsic factor: fruiting season length. This reinstates the importance of food availability on the evolution and maintenance of parental care systems in passerine birds.

  2. Variability and Global Distribution of Subgenotypes of Bovine Viral Diarrhea Virus.

    Science.gov (United States)

    Yeşilbağ, Kadir; Alpay, Gizem; Becher, Paul

    2017-05-26

    Bovine viral diarrhea virus (BVDV) is a globally-distributed agent responsible for numerous clinical syndromes that lead to major economic losses. Two species, BVDV-1 and BVDV-2, discriminated on the basis of genetic and antigenic differences, are classified in the genus Pestivirus within the Flaviviridae family and distributed on all of the continents. BVDV-1 can be segregated into at least twenty-one subgenotypes (1a-1u), while four subgenotypes have been described for BVDV-2 (2a-2d). With respect to published sequences, the number of virus isolates described for BVDV-1 (88.2%) is considerably higher than for BVDV-2 (11.8%). The most frequently-reported BVDV-1 subgenotype are 1b, followed by 1a and 1c. The highest number of various BVDV subgenotypes has been documented in European countries, indicating greater genetic diversity of the virus on this continent. Current segregation of BVDV field isolates and the designation of subgenotypes are not harmonized. While the species BVDV-1 and BVDV-2 can be clearly differentiated independently from the portion of the genome being compared, analysis of different genomic regions can result in inconsistent assignment of some BVDV isolates to defined subgenotypes. To avoid non-conformities the authors recommend the development of a harmonized system for subdivision of BVDV isolates into defined subgenotypes.

  3. Global Lithospheric Apparent Susceptibility Distribution Converted from Geomagnetic Models by CHAMP and Swarm Satellite Magnetic Measurements

    Science.gov (United States)

    Du, Jinsong; Chen, Chao; Xiong, Xiong; Li, Yongdong; Liang, Qing

    2016-04-01

    Recently, because of continually accumulated magnetic measurements by CHAMP satellite and Swarm constellation of three satellites and well developed methodologies and techniques of data processing and geomagnetic field modeling etc., global lithospheric magnetic anomaly field models become more and more reliable. This makes the quantitative interpretation of lithospheric magnetic anomaly field possible for having an insight into large-scale magnetic structures in the crust and uppermost mantle. Many different approaches have been utilized to understand the magnetized sources, such as forward, inversion, statistics, correlation analysis, Euler deconvolution, signal transformations etc. Among all quantitative interpretation methods, the directly converting a magnetic anomaly map into a magnetic susceptibility anomaly map proposed by Arkani-Hamed & Strangway (1985) is, we think, the most fast quantitative interpretation tool for global studies. We just call this method AS85 hereinafter for short. Although Gubbins et al. (2011) provided a formula to directly calculate the apparent magnetic vector distribution, the AS85 method introduced constraints of magnetized direction and thus corresponding results are expected to be more robust especially in world-wide continents. Therefore, in this study, we first improved the AS85 method further considering non-axial dipolar inducing field using formulae by Nolte & Siebert (1987), initial model or priori information for starting coefficients in the apparent susceptibility conversion, hidden longest-wavelength components of lithospheric magnetic field and field contaminations from global oceanic remanent magnetization. Then, we used the vertically integrated susceptibility model by Hemant & Maus (2005) and vertically integrated remanent magnetization model by Masterton et al. (2013) to test the validity of our improved method. Subsequently, we applied the conversion method to geomagnetic field models by CHAMP and Swarm satellite

  4. Distributed team cohesion – not an oxymoron. The impact of information and communications technologies on teamness in globally distributed IT projects

    Directory of Open Access Journals (Sweden)

    Olga Stawnicza

    2015-01-01

    Full Text Available Globally distributed IT projects are common practice in today’s globalized world. Typically, project team members’ work on interdependent tasks, with a common goal to be achieved as one team. However, being split between multiple locations impedes communication among team members and hampers the development of trust. Information and communications media enable communication between geographically distributed project team members and help to create and maintain trust within project units. Communication and trust are particularly significant for fostering a feeling of oneness among project team members. Oneness, also referred to as “teamness”, is repeatedly mentioned as one of the challenges facing global project teams. However, prior literature on teamness is very scarce and its importance is underrepresented. This research contributes to the field in two ways. First, the theoretical study based on a systematic literature review examines available evidence of teamness in globally distributed projects. Secondly, an empirical study based on interviews conducted with global project managers fills the current gap in literature on the link between use of ICT and establishing a sense of team unity. This paper draws practitioners’ attention to the importance of striving for teamness in spite of the geographical distance that exists between project team members.

  5. Interplay between Amazonia Tropical Rain Forest Fires (Mesoscale distribution) and global carbon cycle

    Science.gov (United States)

    Cordeiro, R. C.; Turcq, B.; Sifeddine, A.

    2009-12-01

    Soil samples were collected at 9 different depths, from zero to 100 cm at six points distributed along a transect of 1700 m in upland and lowland areas of the Km 41 reserve near Manaus in Central Brazilian Amazonia, in order to compare the frequency, dimension and extension of past fires in different topographic environmental situations. The average charcoal mass distribution is higher in uplands than in lowlands. This distribution shows a gradient with a high correlation between the two topographic levels, demonstrating a characteristic depth distribution pattern. The highest charcoal concentrations were found at a depth of 20-50 cm in all the six profiles. These fires have affected the upland areas more severely than the lowlands, probably allowing the survival of the vegetation along the small streams.. Two periods of intense fire activity were identified through the distribution of the biomass of charcoal: from around 1320 cal yr BP (ca 1400 14C yr BP) to 1050 cal yr BP (ca 1100 14C yr BP), and between 610 cal yr BP (ca 600 14C yr BP) to 330 cal yr BP (ca 300 yr 14C yr BP). These forest fire phases were probably favored by dry climate which is recorded in other regions of Amazonia and South America by archaeological and palaeoecological data.. Observe that the data found in this article related to the disturbances of fire events in the Central Amazon region appear to be synchronous with events of disruption of populations and vegetation changes and background to the development of indigenous people. Thus it seems plausible that these disturbance phenomena may have an origin presumably climatic than anthropogenic. This possible relationship between climate and forest, ecosystems of high productivity and biomass, and humans should be look carefully in relation to the carbon cycle dynamics demonstrated by the air bubbles extracted of the ice core records.. Increase is observed in the CO2 concentration of the Taylor Dome record just after the increase in frequency

  6. Divergence and gene flow in the globally distributed blue-winged ducks

    Science.gov (United States)

    Nelson, Joel; Wilson, Robert E.; McCracken, Kevin G.; Cumming, Graeme; Joseph, Leo; Guay, Patrick-Jean; Peters, Jeffrey

    2017-01-01

    The ability to disperse over long distances can result in a high propensity for colonizing new geographic regions, including uninhabited continents, and lead to lineage diversification via allopatric speciation. However, high vagility can also result in gene flow between otherwise allopatric populations, and in some cases, parapatric or divergence-with-gene-flow models might be more applicable to widely distributed lineages. Here, we use five nuclear introns and the mitochondrial control region along with Bayesian models of isolation with migration to examine divergence, gene flow, and phylogenetic relationships within a cosmopolitan lineage comprising six species, the blue-winged ducks (genus Anas), which inhabit all continents except Antarctica. We found two primary sub-lineages, the globally-distributed shoveler group and the New World blue-winged/cinnamon teal group. The blue-winged/cinnamon sub-lineage is composed of sister taxa from North America and South America, and taxa with parapatric distributions are characterized by low to moderate levels of gene flow. In contrast, our data support strict allopatry for most comparisons within the shovelers. However, we found evidence of gene flow from the migratory, Holarctic northern shoveler (A. clypeata) and the more sedentary, African Cape shoveler (A. smithii) into the Australasian shoveler (A. rhynchotis), although we could not reject strict allopatry. Given the diverse mechanisms of speciation within this complex, the shovelers and blue-winged/cinnamon teals can serve as an effective model system for examining how the genome diverges under different evolutionary processes and how genetic variation is partitioned among highly dispersive taxa.

  7. Global sensitivity analysis using a new approach based on cumulative distribution functions

    Science.gov (United States)

    Wagener, T.; Pianosi, F.; Sarrazin, F.

    2014-12-01

    Global Sensitivity Analysis (GSA) has become a key tool for the analysis of environmental models. Objectives for GSA include model simplification to support calibration, diagnostic analysis of model controls and subsequent comparison with underlying perceptual models, or decision-making analysis to understand over what range of uncertainty a specific action is robust. Variance-based approaches are most widely used for GSA of environmental models. However, methods that consider the entire Probability Density Function (PDF) of the model output, rather than its variance only, are preferable in cases where variance is not an adequate proxy of uncertainty, e.g. when the output distribution is highly-skewed or multi-modal. Additionally, in contrast to variance-based strategies, they might allow for the mapping of the output on the input space, e.g. a prerequisite for the use of GSA in robust decision-making under uncertainty. Still, the adoption of density-based methods has been limited so far, possibly because they are relatively more difficult to implement. Here we present a novel GSA method, called PAWN, to efficiently compute density-based sensitivity indices, while also enabling the necessary input-output space mapping. The key idea is to characterize output distributions by their Cumulative Distribution Functions, which are easier to derive than PDFs. We discuss and demonstrate the advantages of PAWN by application to numerical and environmental examples. We expect PAWN to increase the application of density-based approaches and to be a necessary complimentary approach to variance-based GSA.

  8. Managing globally distributed expertise with new competence management solutions a big-science collaboration as a pilot case.

    CERN Document Server

    Ferguson, J; Livan, M; Nordberg, M; Salmia, T; Vuola, O

    2003-01-01

    In today's global organisations and networks, a critical factor for effective innovation and project execution is appropriate competence and skills management. The challenges include selection of strategic competences, competence development, and leveraging the competences and skills to drive innovation and collaboration for shared goals. This paper presents a new industrial web-enabled competence management and networking solution and its implementation and piloting in a complex big-science environment of globally distributed competences.

  9. Building essential biodiversity variables (EBVs) of species distribution and abundance at a global scale.

    Science.gov (United States)

    Kissling, W Daniel; Ahumada, Jorge A; Bowser, Anne; Fernandez, Miguel; Fernández, Néstor; García, Enrique Alonso; Guralnick, Robert P; Isaac, Nick J B; Kelling, Steve; Los, Wouter; McRae, Louise; Mihoub, Jean-Baptiste; Obst, Matthias; Santamaria, Monica; Skidmore, Andrew K; Williams, Kristen J; Agosti, Donat; Amariles, Daniel; Arvanitidis, Christos; Bastin, Lucy; De Leo, Francesca; Egloff, Willi; Elith, Jane; Hobern, Donald; Martin, David; Pereira, Henrique M; Pesole, Graziano; Peterseil, Johannes; Saarenmaa, Hannu; Schigel, Dmitry; Schmeller, Dirk S; Segata, Nicola; Turak, Eren; Uhlir, Paul F; Wee, Brian; Hardisty, Alex R

    2017-08-02

    Much biodiversity data is collected worldwide, but it remains challenging to assemble the scattered knowledge for assessing biodiversity status and trends. The concept of Essential Biodiversity Variables (EBVs) was introduced to structure biodiversity monitoring globally, and to harmonize and standardize biodiversity data from disparate sources to capture a minimum set of critical variables required to study, report and manage biodiversity change. Here, we assess the challenges of a 'Big Data' approach to building global EBV data products across taxa and spatiotemporal scales, focusing on species distribution and abundance. The majority of currently available data on species distributions derives from incidentally reported observations or from surveys where presence-only or presence-absence data are sampled repeatedly with standardized protocols. Most abundance data come from opportunistic population counts or from population time series using standardized protocols (e.g. repeated surveys of the same population from single or multiple sites). Enormous complexity exists in integrating these heterogeneous, multi-source data sets across space, time, taxa and different sampling methods. Integration of such data into global EBV data products requires correcting biases introduced by imperfect detection and varying sampling effort, dealing with different spatial resolution and extents, harmonizing measurement units from different data sources or sampling methods, applying statistical tools and models for spatial inter- or extrapolation, and quantifying sources of uncertainty and errors in data and models. To support the development of EBVs by the Group on Earth Observations Biodiversity Observation Network (GEO BON), we identify 11 key workflow steps that will operationalize the process of building EBV data products within and across research infrastructures worldwide. These workflow steps take multiple sequential activities into account, including identification and

  10. Patient safety: the landscape of the global research output and gender distribution.

    Science.gov (United States)

    Schreiber, Moritz; Klingelhöfer, Doris; Groneberg, David A; Brüggmann, Doerthe

    2016-02-12

    Patient safety is a crucial issue in medicine. Its main objective is to reduce the number of deaths and health damages that are caused by preventable medical errors. To achieve this, it needs better health systems that make mistakes less likely and their effects less detrimental without blaming health workers for failures. Until now, there is no in-depth scientometric analysis on this issue that encompasses the interval between 1963 and 2014. Therefore, the aim of this study is to sketch a landscape of the past global research output on patient safety including the gender distribution of the medical discipline of patient safety by interpreting scientometric parameters. Additionally, respective future trends are to be outlined. The Core Collection of the scientific database Web of Science was searched for publications with the search term 'Patient Safety' as title word that was focused on the corresponding medical discipline. The resulting data set was analysed by using the methodology implemented by the platform NewQIS. To visualise the geographical landscape, state-of-the-art techniques including density-equalising map projections were applied. 4079 articles on patient safety were identified in the period from 1900 to 2014. Most articles were published in North America, the UK and Australia. In regard to the overall number of publications, the USA is the leading country, while the output ratio to the population of Switzerland was found to exhibit the best performance. With regard to the ratio of the number of publications to the Gross Domestic Product (GDP) per Capita, the USA remains the leading nation but countries like India and China with a low GDP and high population numbers are also profiting. Though the topic is a global matter, the scientific output on patient safety is centred mainly in industrialised countries. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  11. The global distribution of fatal pesticide self-poisoning: Systematic review

    Science.gov (United States)

    Gunnell, David; Eddleston, Michael; Phillips, Michael R; Konradsen, Flemming

    2007-01-01

    Background Evidence is accumulating that pesticide self-poisoning is one of the most commonly used methods of suicide worldwide, but the magnitude of the problem and the global distribution of these deaths is unknown. Methods We have systematically reviewed the worldwide literature to estimate the number of pesticide suicides in each of the World Health Organisation's six regions and the global burden of fatal self-poisoning with pesticides. We used the following data sources: Medline, EMBASE and psycINFO (1990–2007), papers cited in publications retrieved, the worldwide web (using Google) and our personal collections of papers and books. Our aim was to identify papers enabling us to estimate the proportion of a country's suicides due to pesticide self-poisoning. Results We conservatively estimate that there are 258,234 (plausible range 233,997 to 325,907) deaths from pesticide self-poisoning worldwide each year, accounting for 30% (range 27% to 37%) of suicides globally. Official data from India probably underestimate the incidence of suicides; applying evidence-based corrections to India's official data, our estimate for world suicides using pesticides increases to 371,594 (range 347,357 to 439,267). The proportion of all suicides using pesticides varies from 4% in the European Region to over 50% in the Western Pacific Region but this proportion is not concordant with the volume of pesticides sold in each region; it is the pattern of pesticide use and the toxicity of the products, not the quantity used, that influences the likelihood they will be used in acts of fatal self-harm. Conclusion Pesticide self-poisoning accounts for about one-third of the world's suicides. Epidemiological and toxicological data suggest that many of these deaths might be prevented if (a) the use of pesticides most toxic to humans was restricted, (b) pesticides could be safely stored in rural communities, and (c) the accessibility and quality of care for poisoning could be improved

  12. The global distribution of fatal pesticide self-poisoning: Systematic review

    Directory of Open Access Journals (Sweden)

    Eddleston Michael

    2007-12-01

    Full Text Available Abstract Background Evidence is accumulating that pesticide self-poisoning is one of the most commonly used methods of suicide worldwide, but the magnitude of the problem and the global distribution of these deaths is unknown. Methods We have systematically reviewed the worldwide literature to estimate the number of pesticide suicides in each of the World Health Organisation's six regions and the global burden of fatal self-poisoning with pesticides. We used the following data sources: Medline, EMBASE and psycINFO (1990–2007, papers cited in publications retrieved, the worldwide web (using Google and our personal collections of papers and books. Our aim was to identify papers enabling us to estimate the proportion of a country's suicides due to pesticide self-poisoning. Results We conservatively estimate that there are 258,234 (plausible range 233,997 to 325,907 deaths from pesticide self-poisoning worldwide each year, accounting for 30% (range 27% to 37% of suicides globally. Official data from India probably underestimate the incidence of suicides; applying evidence-based corrections to India's official data, our estimate for world suicides using pesticides increases to 371,594 (range 347,357 to 439,267. The proportion of all suicides using pesticides varies from 4% in the European Region to over 50% in the Western Pacific Region but this proportion is not concordant with the volume of pesticides sold in each region; it is the pattern of pesticide use and the toxicity of the products, not the quantity used, that influences the likelihood they will be used in acts of fatal self-harm. Conclusion Pesticide self-poisoning accounts for about one-third of the world's suicides. Epidemiological and toxicological data suggest that many of these deaths might be prevented if (a the use of pesticides most toxic to humans was restricted, (b pesticides could be safely stored in rural communities, and (c the accessibility and quality of care for poisoning

  13. Improving the understanding of the global distribution of the Radioxenon Background caused by known civil emissions and its consequences for CTBT verification

    Science.gov (United States)

    Wotawa, G.; Becker, A.; Kalinowski, M.; Saey, P.; Tuma, M.; Zaehringer, M.

    2009-04-01

    Monitoring of radioactive noble gases, in particular xenon radioisotopes, is a crucial activity for the verification of the Comprehensive Nuclear-Test-Ban Treaty. In a previous study, it was found that the distribution and magnitude of the global background of the isotope xenon-133 measured at stations of the International Monitoring System is to a large extent consistent with the hypothesis that it results from the currently known civil sources, namely isotope production facilities and nuclear power plants. In the new study, more sophisticated methodologies for background simulation and comparison are applied. All available data on the temporal variations of emissions and production cycles from the background dominating facilities Chalk River in Canada and Fleurus in Belgium are taken into account. Particularly data from the year 2008 provide a unique opportunity to allocate fractions of site specific background to individual sources as there have been several longer downtime periods of major xenon sources. Furthermore, an attempt to better account for batch releases from reactors in a statistical way based on the emission studies available is presented. The subsequent data analysis is enhanced by including not only daily and annual observation values, but also weekly and monthly median values from each station. Consequently, a more complete and consistent picture on the global xenon-133 emissions is presented, and improved conclusions regarding the verification of the CTBT based on noble gas monitoring are drawn. Finally, computations are also expanded to the other three relevant radioxenon isotopes.

  14. The global distribution of bamboos: assessing correlates of introduction and invasion

    Science.gov (United States)

    Richardson, David M.; Visser, Vernon; Le Roux, Johannes J.; Vorontsova, Maria S.; Wilson, John R. U.

    2017-01-01

    Abstract There is a long history of species being moved around the world by humans. These introduced species can provide substantial benefits, but they can also have undesirable consequences. We explore the importance of human activities on the processes of species dissemination and potential invasions using the Poaceae subfamily Bambusoideae (‘bamboos’), a group that contains taxa that are widely utilised and that are often perceived as weedy. We (1) compiled an inventory of bamboo species and their current distributions; (2) determined which species have been introduced and become invasive outside their native ranges; and (3) explored correlates of introduction and invasion. Distribution data were collated from Kew’s GrassBase, the Global Biodiversity Information Facility and other online herbarium information sources. Our list comprised 1662 species in 121 genera, of which 232 (14 %) have been introduced beyond their native ranges. Twelve (0.7 % of species) were found to be invasive. A non-random selection of bamboos have been introduced and become invasive. Asiatic species in particular have been widely introduced. There was a clear over-representation of introduced species in the genera Bambusa and Phyllostachys which also contain most of the listed invasive species. The introduction of species also correlated with certain traits: taxa with larger culm dimensions were significantly more likely to have been moved to new areas; and those with many cultivars had a higher rate of dissemination and invasion. It is difficult to determine whether the patterns of introduction and invasion are due simply to differences in propagule pressure, or whether humans have deliberately selected inherently invasive taxa. In general, we suggest that human usage is a stronger driver of introductions and invasions in bamboos than in other taxa that have been well studied. It is likely that as bamboos are used more widely, the number and impact of invasions will increase

  15. Globalization

    DEFF Research Database (Denmark)

    Plum, Maja

    Globalization is often referred to as external to education - a state of affair facing the modern curriculum with numerous challenges. In this paper it is examined as internal to curriculum; analysed as a problematization in a Foucaultian sense. That is, as a complex of attentions, worries, ways...... of reasoning, producing curricular variables. The analysis is made through an example of early childhood curriculum in Danish Pre-school, and the way the curricular variable of the pre-school child comes into being through globalization as a problematization, carried forth by the comparative practices of PISA...

  16. The influence of global sea level changes on European shale distribution and gas exploration

    Energy Technology Data Exchange (ETDEWEB)

    Turner, P.; Cornelius, C.T.; Clarke, H. [Cuadrilla Resources Ltd., Staffordshire (United Kingdom)

    2010-07-01

    Technological advances in directional drilling and hydraulic fracturing technology have unlocked new supplies of shale gas from reservoirs that were previously considered to be uneconomic. Several companies, both experienced majors and small independents, are currently evaluating the unconventional resource potential of mainland Europe. This paper demonstrated that global sea level changes govern the distribution of marine black shales. The Hallam Curve was used in this study to identify periods of prospective gas shale deposition. In general, these correspond to post-glacial periods of relatively high sea level. Under-filled marginal sedimentary basins are key exploration targets. The geochemical and petrophysical characteristics of the shales deposited under these conditions are often comparable to North American shales, particularly the Barnett Shale which is currently in production. Many orogenic events influence European shales in terms of organic maturity, hydrocarbon generation and fracture generation. The main prospective horizons in ascending stratigraphic sequence are the Alum Shale, Llandovery Shale, Fammenian/Frasnian Shale, Serpukhovian Shale, Toarcian Shale, Kimmeridge Clay and the Tertiary Eocene and Oligocene shales common to central Europe. This paper presented the authors initial exploration strategy, with particular focus on the Lower Palaeozoic of central Europe, the Namurian of northwest England and the Jurassic Posidonia Formation of the Roer Valley Graben in Holland. The potential obstacles to unconventional exploration in Europe include restricted access to surface locations, high water usage, a lack of convenient pipeline infrastructure, strict environmental regulations, a high population density and lack of suitable drilling rigs and well completion equipment. 13 refs., 7 figs.

  17. Environmental stability affects phenotypic evolution in a globally distributed marine picoplankton

    Science.gov (United States)

    Schaum, C-Elisa; Rost, Björn; Collins, Sinéad

    2016-01-01

    Marine phytoplankton can evolve rapidly when confronted with aspects of climate change because of their large population sizes and fast generation times. Despite this, the importance of environment fluctuations, a key feature of climate change, has received little attention—selection experiments with marine phytoplankton are usually carried out in stable environments and use single or few representatives of a species, genus or functional group. Here we investigate whether and by how much environmental fluctuations contribute to changes in ecologically important phytoplankton traits such as C:N ratios and cell size, and test the variability of changes in these traits within the globally distributed species Ostreococcus. We have evolved 16 physiologically distinct lineages of Ostreococcus at stable high CO2 (1031±87 μatm CO2, SH) and fluctuating high CO2 (1012±244 μatm CO2, FH) for 400 generations. We find that although both fluctuation and high CO2 drive evolution, FH-evolved lineages are smaller, have reduced C:N ratios and respond more strongly to further increases in CO2 than do SH-evolved lineages. This indicates that environmental fluctuations are an important factor to consider when predicting how the characteristics of future phytoplankton populations will have an impact on biogeochemical cycles and higher trophic levels in marine food webs. PMID:26125683

  18. Locating ethics in data science: responsibility and accountability in global and distributed knowledge production systems.

    Science.gov (United States)

    Leonelli, Sabina

    2016-12-28

    The distributed and global nature of data science creates challenges for evaluating the quality, import and potential impact of the data and knowledge claims being produced. This has significant consequences for the management and oversight of responsibilities and accountabilities in data science. In particular, it makes it difficult to determine who is responsible for what output, and how such responsibilities relate to each other; what 'participation' means and which accountabilities it involves, with regard to data ownership, donation and sharing as well as data analysis, re-use and authorship; and whether the trust placed on automated tools for data mining and interpretation is warranted (especially as data processing strategies and tools are often developed separately from the situations of data use where ethical concerns typically emerge). To address these challenges, this paper advocates a participative, reflexive management of data practices. Regulatory structures should encourage data scientists to examine the historical lineages and ethical implications of their work at regular intervals. They should also foster awareness of the multitude of skills and perspectives involved in data science, highlighting how each perspective is partial and in need of confrontation with others. This approach has the potential to improve not only the ethical oversight for data science initiatives, but also the quality and reliability of research outputs.This article is part of the themed issue 'The ethical impact of data science'. © 2015 The Authors.

  19. Global distribution and Gas-particle Partitioning of Polycyclic Aromatic Hydrocarbons - a Modelling Study

    Science.gov (United States)

    Lammel, G.; Sehili, A. M.

    2009-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are emitted in all combustion processes. Some undergo re-volatilisation (multi-hopping). Little is known about degradation pathways and the processes determining gas-particle partitioning (Lohmann & Lammel, 2004). Distribution and fate have no been studied on the global scale so far (except for emissions in Europe and Russia; Sehili & Lammel, 2007). Anthracene (ANT), fluoranthene (FLT) and benzo[a]pyrene (BAP) have been studied under present-day climate and each 3 scenarios of atmospheric degradation and gas-particle partitioning using an atmospheric general circulation model with embedded dynamic aerosol submodel, ECHAM-HAM (Stier et al., 2005) and re-volatilization from ground compartments (Semeena et al., 2006). 10 years were simulated with a time-step of 30 min and 2.8°x2.8° and 19 levels. Emissions were compiled based on emission factors in 27 major types of combustion technologies, scaled to 141 combustion technologies and their global distribution as of 1996 (1°x1°) according to fuel type and the PM1 emission factor (Bond et al., 2004). The emissions were entried uniformly throughout the entire simulation time. Scenarios tested: AD = adsorption (according to the Junge empirical relationship; Pankow, 1987), OB = absorption in organic matter and adsorption to soot (Lohmann & Lammel, 2004) without and DP = with degradation in the atmospheric particulate phase. Gas-particle partitioning in air influences drastically the atmospheric cycling, total environmental fate (e.g. compartmental distributions) and the long-range transport potential (LRTP) of the substances studied. The LRTP is mostly regional. Comparison with observed levels indicate that degradation in the particulate phase must be slower than in the gas-phase. Furthermore, the levels of semivolatile PAHs (ANT and FLT) at high latitudes and a European mid latitude site cannot be explained by partitioning due to adsorption alone, but point to both absorption into

  20. Speciation despite globally overlapping distributions in Penicillium chrysogenum: the population genetics of Alexander Fleming’s lucky fungus

    Science.gov (United States)

    Eighty years ago, Alexander Fleming described the antibiotic effects of a fungus that had contaminated his bacterial culture, kick starting the antimicrobial revolution. The fungus was later ascribed to a globally distributed asexual species, Penicillium chrysogenum. Recently, the species has been...

  1. Modeling of the global distribution of ionospheric electric fields based on realistic maps of field-aligned currents

    DEFF Research Database (Denmark)

    Lukianova, R.; Christiansen, Freddy

    2006-01-01

    [1] A new approach for modeling the global distribution of ionospheric electric potentials utilizing high-precision maps of FACs derived from measurements by the Orsted and Champ satellites as input to a comprehensive numerical scheme is presented. The boundary conditions provide a correct treatm...

  2. Satellite observations of tropospheric ammonia and carbon monoxide: Global distributions, regional correlations and comparisons to model simulations

    Science.gov (United States)

    Ammonia (NH3) and carbon monoxide (CO) are primary pollutants emitted to the Earth's atmosphere from common as well as distinct sources associated with anthropogenic and natural activities. The seasonal and global distributions and correlations of NH3 and CO from the Tropospheric...

  3. The importance of the human footprint in shaping the global distribution of terrestrial, freshwater and marine invaders.

    Directory of Open Access Journals (Sweden)

    Belinda Gallardo

    Full Text Available Human activities such as transport, trade and tourism are likely to influence the spatial distribution of non-native species and yet, Species Distribution Models (SDMs that aim to predict the future broad scale distribution of invaders often rely on environmental (e.g. climatic information only. This study investigates if and to what extent do human activities that directly or indirectly influence nature (hereafter the human footprint affect the global distribution of invasive species in terrestrial, freshwater and marine ecosystems. We selected 72 species including terrestrial plants, terrestrial animals, freshwater and marine invasive species of concern in a focus area located in NW Europe (encompassing Great Britain, France, The Netherlands and Belgium. Species Distribution Models were calibrated with the global occurrence of species and a set of high-resolution (9×9 km environmental (e.g. topography, climate, geology layers and human footprint proxies (e.g. the human influence index, population density, road proximity. Our analyses suggest that the global occurrence of a wide range of invaders is primarily limited by climate. Temperature tolerance was the most important factor and explained on average 42% of species distribution. Nevertheless, factors related to the human footprint explained a substantial amount (23% on average of species distributions. When global models were projected into the focus area, spatial predictions integrating the human footprint featured the highest cumulative risk scores close to transport networks (proxy for invasion pathways and in habitats with a high human influence index (proxy for propagule pressure. We conclude that human related information-currently available in the form of easily accessible maps and databases-should be routinely implemented into predictive frameworks to inform upon policies to prevent and manage invasions. Otherwise we might be seriously underestimating the species and areas under

  4. The importance of the human footprint in shaping the global distribution of terrestrial, freshwater and marine invaders.

    Science.gov (United States)

    Gallardo, Belinda; Zieritz, Alexandra; Aldridge, David C

    2015-01-01

    Human activities such as transport, trade and tourism are likely to influence the spatial distribution of non-native species and yet, Species Distribution Models (SDMs) that aim to predict the future broad scale distribution of invaders often rely on environmental (e.g. climatic) information only. This study investigates if and to what extent do human activities that directly or indirectly influence nature (hereafter the human footprint) affect the global distribution of invasive species in terrestrial, freshwater and marine ecosystems. We selected 72 species including terrestrial plants, terrestrial animals, freshwater and marine invasive species of concern in a focus area located in NW Europe (encompassing Great Britain, France, The Netherlands and Belgium). Species Distribution Models were calibrated with the global occurrence of species and a set of high-resolution (9×9 km) environmental (e.g. topography, climate, geology) layers and human footprint proxies (e.g. the human influence index, population density, road proximity). Our analyses suggest that the global occurrence of a wide range of invaders is primarily limited by climate. Temperature tolerance was the most important factor and explained on average 42% of species distribution. Nevertheless, factors related to the human footprint explained a substantial amount (23% on average) of species distributions. When global models were projected into the focus area, spatial predictions integrating the human footprint featured the highest cumulative risk scores close to transport networks (proxy for invasion pathways) and in habitats with a high human influence index (proxy for propagule pressure). We conclude that human related information-currently available in the form of easily accessible maps and databases-should be routinely implemented into predictive frameworks to inform upon policies to prevent and manage invasions. Otherwise we might be seriously underestimating the species and areas under highest risk

  5. The Importance of the Human Footprint in Shaping the Global Distribution of Terrestrial, Freshwater and Marine Invaders

    Science.gov (United States)

    Gallardo, Belinda; Zieritz, Alexandra; Aldridge, David C.

    2015-01-01

    Human activities such as transport, trade and tourism are likely to influence the spatial distribution of non-native species and yet, Species Distribution Models (SDMs) that aim to predict the future broad scale distribution of invaders often rely on environmental (e.g. climatic) information only. This study investigates if and to what extent do human activities that directly or indirectly influence nature (hereafter the human footprint) affect the global distribution of invasive species in terrestrial, freshwater and marine ecosystems. We selected 72 species including terrestrial plants, terrestrial animals, freshwater and marine invasive species of concern in a focus area located in NW Europe (encompassing Great Britain, France, The Netherlands and Belgium). Species Distribution Models were calibrated with the global occurrence of species and a set of high-resolution (9×9 km) environmental (e.g. topography, climate, geology) layers and human footprint proxies (e.g. the human influence index, population density, road proximity). Our analyses suggest that the global occurrence of a wide range of invaders is primarily limited by climate. Temperature tolerance was the most important factor and explained on average 42% of species distribution. Nevertheless, factors related to the human footprint explained a substantial amount (23% on average) of species distributions. When global models were projected into the focus area, spatial predictions integrating the human footprint featured the highest cumulative risk scores close to transport networks (proxy for invasion pathways) and in habitats with a high human influence index (proxy for propagule pressure). We conclude that human related information–currently available in the form of easily accessible maps and databases—should be routinely implemented into predictive frameworks to inform upon policies to prevent and manage invasions. Otherwise we might be seriously underestimating the species and areas under highest

  6. A conceptual framework to study the role of communication through social software for coordination in globally-distributed software teams

    DEFF Research Database (Denmark)

    Giuffrida, Rosalba; Dittrich, Yvonne

    2015-01-01

    with geographical distance; however, in Software Engineering literature, there is a lack of suitable theoretical concepts to analyze and describe everyday practices of globally-distributed software development teams and to study the role of communication through SoSo. Objective The paper proposes a theoretical...... framework for analyzing how communicative and coordinative practices are constituted and maintained in globally-distributed teams. Method The framework is based on the concepts of communicative genres and coordination mechanisms; it is motivated and explicated through examples from two qualitative empirical......Background In Global Software Development (GSD) the lack of face-to-face communication is a major challenge and effective computer-mediated practices are necessary to mitigate the effect of physical distance. Communication through Social Software (SoSo) supports team coordination, helping to deal...

  7. Global auroral conductance distribution due to electron and proton precipitation from IMAGE-FUV observations

    Directory of Open Access Journals (Sweden)

    V. Coumans

    2004-04-01

    Full Text Available The Far Ultraviolet (FUV imaging system on board the IMAGE satellite provides a global view of the north auroral region in three spectral channels, including the SI12 camera sensitive to Doppler shifted Lyman-α emission. FUV images are used to produce instantaneous maps of electron mean energy and energy fluxes for precipitated protons and electrons. We describe a method to calculate ionospheric Hall and Pedersen conductivities induced by auroral proton and electron ionization based on a model of interaction of auroral particles with the atmosphere. Different assumptions on the energy spectral distribution for electrons and protons are compared. Global maps of ionospheric conductances due to instantaneous observation of precipitating protons are calculated. The contribution of auroral protons in the total conductance induced by both types of auroral particles is also evaluated and the importance of proton precipitation is evaluated. This method is well adapted to analyze the time evolution of ionospheric conductances due to precipitating particles over the auroral region or in particular sectors. Results are illustrated with conductance maps of the north polar region obtained during four periods with different activity levels. It is found that the proton contribution to conductance is relatively higher during quiet periods than during substorms. The proton contribution is higher in the period before the onset and strongly decreases during the expansion phase of substorms. During a substorm which occurred on 28 April 2001, a region of strong proton precipitation is observed with SI12 around 14:00MLT at ~75° MLAT. Calculation of conductances in this sector shows that neglecting the protons contribution would produce a large error. We discuss possible effects of the proton precipitation on electron precipitation in auroral arcs. The increase in the ionospheric conductivity, induced by a former proton precipitation can reduce the potential drop

  8. Global auroral conductance distribution due to electron and proton precipitation from IMAGE-FUV observations

    Directory of Open Access Journals (Sweden)

    V. Coumans

    2004-04-01

    Full Text Available The Far Ultraviolet (FUV imaging system on board the IMAGE satellite provides a global view of the north auroral region in three spectral channels, including the SI12 camera sensitive to Doppler shifted Lyman-α emission. FUV images are used to produce instantaneous maps of electron mean energy and energy fluxes for precipitated protons and electrons. We describe a method to calculate ionospheric Hall and Pedersen conductivities induced by auroral proton and electron ionization based on a model of interaction of auroral particles with the atmosphere. Different assumptions on the energy spectral distribution for electrons and protons are compared. Global maps of ionospheric conductances due to instantaneous observation of precipitating protons are calculated. The contribution of auroral protons in the total conductance induced by both types of auroral particles is also evaluated and the importance of proton precipitation is evaluated. This method is well adapted to analyze the time evolution of ionospheric conductances due to precipitating particles over the auroral region or in particular sectors. Results are illustrated with conductance maps of the north polar region obtained during four periods with different activity levels. It is found that the proton contribution to conductance is relatively higher during quiet periods than during substorms. The proton contribution is higher in the period before the onset and strongly decreases during the expansion phase of substorms. During a substorm which occurred on 28 April 2001, a region of strong proton precipitation is observed with SI12 around 14:00MLT at ~75° MLAT. Calculation of conductances in this sector shows that neglecting the protons contribution would produce a large error. We discuss possible effects of the proton precipitation on electron precipitation in auroral arcs. The increase in the ionospheric conductivity, induced by a former proton precipitation can reduce the potential drop

  9. The impact of global warming on the range distribution of different climatic groups of Aspidoscelis costata costata.

    Science.gov (United States)

    Güizado-Rodríguez, Martha Anahí; Ballesteros-Barrera, Claudia; Casas-Andreu, Gustavo; Barradas-Miranda, Victor Luis; Téllez-Valdés, Oswaldo; Salgado-Ugarte, Isaías Hazarmabeth

    2012-12-01

    The ectothermic nature of reptiles makes them especially sensitive to global warming. Although climate change and its implications are a frequent topic of detailed studies, most of these studies are carried out without making a distinction between populations. Here we present the first study of an Aspidoscelis species that evaluates the effects of global warming on its distribution using ecological niche modeling. The aims of our study were (1) to understand whether predicted warmer climatic conditions affect the geographic potential distribution of different climatic groups of Aspidoscelis costata costata and (2) to identify potential altitudinal changes of these groups under global warming. We used the maximum entropy species distribution model (MaxEnt) to project the potential distributions expected for the years 2020, 2050, and 2080 under a single simulated climatic scenario. Our analysis suggests that some climatic groups of Aspidoscelis costata costata will exhibit reductions and in others expansions in their distribution, with potential upward shifts toward higher elevation in response to climate warming. Different climatic groups were revealed in our analysis that subsequently showed heterogeneous responses to climatic change illustrating the complex nature of species geographic responses to environmental change and the importance of modeling climatic or geographic groups and/or populations instead of the entire species' range treated as a homogeneous entity.

  10. Global assessment of soil organic carbon stocks and spatial distribution of histosols: the Machine Learning approach

    Science.gov (United States)

    Hengl, Tomislav

    2016-04-01

    Preliminary results of predicting distribution of soil organic soils (Histosols) and soil organic carbon stock (in tonnes per ha) using global compilations of soil profiles (about 150,000 points) and covariates at 250 m spatial resolution (about 150 covariates; mainly MODIS seasonal land products, SRTM DEM derivatives, climatic images, lithological and land cover and landform maps) are presented. We focus on using a data-driven approach i.e. Machine Learning techniques that often require no knowledge about the distribution of the target variable or knowledge about the possible relationships. Other advantages of using machine learning are (DOI: 10.1371/journal.pone.0125814): All rules required to produce outputs are formalized. The whole procedure is documented (the statistical model and associated computer script), enabling reproducible research. Predicted surfaces can make use of various information sources and can be optimized relative to all available quantitative point and covariate data. There is more flexibility in terms of the spatial extent, resolution and support of requested maps. Automated mapping is also more cost-effective: once the system is operational, maintenance and production of updates are an order of magnitude faster and cheaper. Consequently, prediction maps can be updated and improved at shorter and shorter time intervals. Some disadvantages of automated soil mapping based on Machine Learning are: Models are data-driven and any serious blunders or artifacts in the input data can propagate to order-of-magnitude larger errors than in the case of expert-based systems. Fitting machine learning models is at the order of magnitude computationally more demanding. Computing effort can be even tens of thousands higher than if e.g. linear geostatistics is used. Many machine learning models are fairly complex often abstract and any interpretation of such models is not trivial and require special multidimensional / multivariable plotting and data mining

  11. Potential distribution of the Australian native Chloris truncata based on modelling both the successful and failed global introductions.

    Directory of Open Access Journals (Sweden)

    Pippa J Michael

    Full Text Available Our aim was to model the current and future potential global distribution of Chloris truncata (windmill grass based on the plant's biology, soil requirements and colonisation success. The growth response of C. truncata to constant temperatures and soil moisture levels were measured and estimated respectively, to develop parameters for a CLIMEX bioclimatic model of potential distribution. The native distribution in eastern Australia and naturalised distribution in Western Australia was also used to inform the model. Associations with soil types were assessed within the suitable bioclimatic region in Australia. The global projection of the model was tested against the distribution of soil types and the known successful and failed global introductions. The verified model was then projected to future conditions due to climate change. Optimal temperature for plant development was 28°C and the plant required 970 degree-days above a threshold of 10°C. Early collection records indicate that the species is native to Queensland, New South Wales and Victoria. The plant has been introduced elsewhere in Australia and throughout the world as a wool contaminant and as a potential pasture species, but some of the recorded establishments have failed to persist. The CLIMEX model projected to the world reflected effectively both the successful and failed distributions. The inclusion of soil associations improved the explanation of the observed distribution in Australia, but did not improve the ability to determine the potential distribution elsewhere, due to lack of similarity of soil types between continents. The addition of a climate change projection showed decreased suitability for this species in Australia, but increased suitability for other parts of the world, including regions where the plant previously failed to establish.

  12. Using R for Global Optimization of a Fully-distributed Hydrologic Model at Continental Scale

    Science.gov (United States)

    Zambrano-Bigiarini, M.; Zajac, Z.; Salamon, P.

    2013-12-01

    Nowadays hydrologic model simulations are widely used to better understand hydrologic processes and to predict extreme events such as floods and droughts. In particular, the spatially distributed LISFLOOD model is currently used for flood forecasting at Pan-European scale, within the European Flood Awareness System (EFAS). Several model parameters can not be directly measured, and they need to be estimated through calibration, in order to constrain simulated discharges to their observed counterparts. In this work we describe how the free software 'R' has been used as a single environment to pre-process hydro-meteorological data, to carry out global optimization, and to post-process calibration results in Europe. Historical daily discharge records were pre-processed for 4062 stream gauges, with different amount and distribution of data in each one of them. The hydroTSM, raster and sp R packages were used to select ca. 700 stations with an adequate spatio-temporal coverage. Selected stations span a wide range of hydro-climatic characteristics, from arid and ET-dominated watersheds in the Iberian Peninsula to snow-dominated watersheds in Scandinavia. Nine parameters were selected to be calibrated based on previous expert knowledge. Customized R scripts were used to extract observed time series for each catchment and to prepare the input files required to fully set up the calibration thereof. The hydroPSO package was then used to carry out a single-objective global optimization on each selected catchment, by using the Standard Particle Swarm 2011 (SPSO-2011) algorithm. Among the many goodness-of-fit measures available in the hydroGOF package, the Nash-Sutcliffe efficiency was used to drive the optimization. User-defined functions were developed for reading model outputs and passing them to the calibration engine. The long computational time required to finish the calibration at continental scale was partially alleviated by using 4 multi-core machines (with both GNU

  13. Specific Features of Transport Market Characterising the Interrelation of Logistics, Global Distribution and Traffic

    Directory of Open Access Journals (Sweden)

    Teodor Perić

    2002-11-01

    Full Text Available If we acknowledge the role of traffic as active leaderof the sustainable economy development, then we certainlyhave to analyse the environment in which the traffic exists asa system, and therefore we have to foresee its limits which aredetermined by the specifics of the traffic system. Representingthe circulation system of economy, traffic has to eavesdrop onthe demands of the market, and has to be transformed andmodernised. The experience gained by working on the projectsand the studies related to business organisation resulted inthe conclusion that the requirements related to logistics inthe nineties were significantly greater than had been thecommon target until then -reduction of costs. In order to adjustcompletely to the market demands, with the help of advancedinformation technology, the companies apply logisticsas tools of competitiveness on the market. Extraordinmyachievements of IT, using of virtual reality enable businesspeople to communicate and contract businesses without beingphysically present. What is it that makes some companies moresuccessful than others? It is obviously a question of the advantagesof distribution realisation due to the fact that nowadayspurchase and selling are run globally in the world. The distributionof products at the right time, to the right place, at a pricewhich is favourable both to the seller and the buyer, in the rightmanner and in the appropriate quantity in the marketing senseis the prerequisite for the business success as element of businesslogistics. The development of this tool must be basedon the monitoring of the needs for the logistics managementand the tactical adaptability of the company. The solution oflogistics management of business processes must satisfy thecurrent and future customers' requirements in order to be competitive.

  14. Global Potential Distribution of Bactrocera carambolae and the Risks for Fruit Production in Brazil.

    Directory of Open Access Journals (Sweden)

    Cesar A Marchioro

    Full Text Available The carambola fruit fly, Bactrocera carambolae, is a tephritid native to Asia that has invaded South America through small-scale trade of fruits from Indonesia. The economic losses associated with biological invasions of other fruit flies around the world and the polyphagous behaviour of B. carambolae have prompted much concern among government agencies and farmers with the potential spread of this pest. Here, ecological niche models were employed to identify suitable environments available to B. carambolae in a global scale and assess the extent of the fruit acreage that may be at risk of attack in Brazil. Overall, 30 MaxEnt models built with different combinations of environmental predictors and settings were evaluated for predicting the potential distribution of the carambola fruit fly. The best model was selected based on threshold-independent and threshold-dependent metrics. Climatically suitable areas were identified in tropical and subtropical regions of Central and South America, Sub-Saharan Africa, west and east coast of India and northern Australia. The suitability map of B. carambola was intersected against maps of fruit acreage in Brazil. The acreage under potential risk of attack varied widely among fruit species, which is expected because the production areas are concentrated in different regions of the country. The production of cashew is the one that is at higher risk, with almost 90% of its acreage within the suitable range of B. carambolae, followed by papaya (78%, tangerine (51%, guava (38%, lemon (30%, orange (29%, mango (24% and avocado (20%. This study provides an important contribution to the knowledge of the ecology of B. carambolae, and the information generated here can be used by government agencies as a decision-making tool to prevent the carambola fruit fly spread across the world.

  15. The expanding role of civil society in the global HIV/AIDS response: what has the President's Emergency Program For AIDS Relief's role been?

    Science.gov (United States)

    Coutinho, Alex; Roxo, Uchechi; Epino, Henry; Muganzi, Alex; Dorward, Emily; Pick, Billy

    2012-08-15

    Civil society has been part of the HIV/AIDS response from the very beginning of the epidemic, often becoming engaged before national governments. Traditional roles of civil society--advocacy, activism, serving as government watchdog, and acting as community caretaker--have been critical to the response. In addition, civil society organizations (CSOs) play an integral part in providing world-class HIV prevention and treatment services and helping to ensure continuity of care. The President's Emergency Program for AIDS Relief (PEPFAR) has significantly increased the global scale-up of combination antiretroviral therapy reaching for more than 5 million people in developing countries, as well as implementation of effective evidence-based combination prevention approaches. PEPFAR databases in 5 countries and annual reports from a centrally managed initiative were mined and analyzed to determine the numbers and types of CSOs funded by PEPFAR over a 5-year period (2006-2011). Data are also presented from Uganda showing the overall resource growth in CSO working for HIV. Case studies document the evolution of 3 indigenous CSOs that increased the capacity to implement activities with PEPFAR funding. A legacy of PEPFAR has been the growth of civil society to address social and health issues as well as recognition by governments that partnerships with beneficiaries and civil society result in better outcomes. Scale-up of the global response could not have happened without the involvement of civil society and people living with HIV. This game changing partnership to jointly tackle the problems that countries face may well be the greatest benefit emerging from the HIV epidemic.

  16. The effects of global change on the distribution, species richness and life history of European dragonflies

    DEFF Research Database (Denmark)

    Olsen, Kent

    2016-01-01

    in Denmark. It is known from a relatively wide geographical range, though in Europe it is mainly found around the Baltic Sea in Estonia, Finland and Sweden, and locally, away from the coast, in the remaining Fennoscandia. In recent decades, it has expanded westwards across the mainland in Sweden...

  17. Global HCFC-22 measurements with MIPAS: retrieval, validation, global distribution and its evolution over 2005–2012

    Directory of Open Access Journals (Sweden)

    M. Chirkov

    2016-03-01

    Full Text Available We report on HCFC-22 data acquired by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS in the reduced spectral resolution nominal observation mode. The data cover the period from January 2005 to April 2012 and the altitude range from the upper troposphere (above cloud top altitude to about 50 km. The profile retrieval was performed by constrained nonlinear least squares fitting of modelled spectra to the measured limb spectral radiances. The spectral ν4-band at 816.5 ± 13 cm−1 was used for the retrieval. A Tikhonov-type smoothing constraint was applied to stabilise the retrieval. In the lower stratosphere, we find a global volume mixing ratio of HCFC-22 of about 185 pptv in January 2005. The rate of linear growth in the lower latitudes lower stratosphere was about 6 to 7 pptv year−1 in the period 2005–2012. The profiles obtained were compared with ACE-FTS satellite data v3.5, as well as with MkIV balloon profiles and cryosampler balloon measurements. Between 13 and 22 km, average agreement within −3 to +5 pptv (MIPAS – ACE with ACE-FTS v3.5 profiles is demonstrated. Agreement with MkIV solar occultation balloon-borne measurements is within 10–20 pptv below 30 km and worse above, while in situ cryosampler balloon measurements are systematically lower over their full altitude range by 15–50 pptv below 24 km and less than 10 pptv above 28 km. MIPAS HCFC-22 time series below 10 km altitude are shown to agree mostly well to corresponding time series of near-surface abundances from the NOAA/ESRL and AGAGE networks, although a more pronounced seasonal cycle is obvious in the satellite data. This is attributed to tropopause altitude fluctuations and subsidence of polar winter stratospheric air into the troposphere. A parametric model consisting of constant, linear, quasi-biennial oscillation (QBO and several sine and cosine terms with different periods has been fitted to the temporal variation of stratospheric

  18. ENA Observations from the IMAGE Mission: Global Evolution and Validation of the Ring Current Ion Distribution and Future Outlook

    Science.gov (United States)

    Brandt, P. C.; Hsieh, S. Y. W.; Demajistre, R.; Sitnov, M. I.; Stephens, G. K.; Gkioulidou, M.

    2016-12-01

    Energetic Neutral Atom (ENA) imaging is the only technique that can capture the instantaneous state of the ring current ion distribution, which can vary globally on MEDICI, has been defined in the Heliophysics Decadal Survey. In this presentation we provide an overview of the global storm-time ring current ion evolution in the 10-200 keV range for several storms during the 2000-2005 era using ENA observations from the IMAGE mission obtained by the HENA Camera. A constrained linear inversion technique has proven to be one of the more effective and convenient techniques to retrieve the spatial and pitch-angle distributions (PAD) of the ring current. We briefly describe the technique and focus on how to ensure that the unique and best solution has been found by using both simulations using synthetic data and validations against the simultaneous in-situ measurements from the Cluster mission for several geomagnetic storms. Results of the global evolution of the ring current is summarized in terms of build-up and decay, and symmetrization timescales, degree of spatial asymmetry, temporal variability due to injections and spatial variability of PADs. We present comparisons with empirical ring current distributions retrieved from the global magnetic field model TS07d and Van Allen Probes in-situ measurements for similar driving conditions. Lastly, we discuss the lessons learned and implications for the second-generation of imaging missions such as MEDICI.

  19. Climate change and the potential global distribution of Aedes aegypti: spatial modelling using geographical information system and CLIMEX

    Directory of Open Access Journals (Sweden)

    Hassan M. Khormi

    2014-05-01

    Full Text Available We examined the potential added risk posed by global climate change on the dengue vector Aedes aegypti abundance using CLIMEX, a powerful tool for exploring the relationship between the fundamental and realised niche of any species. After calibrating the model using data from several knowledge domains, including geographical distribution records, we estimated potential distributions of the mosquito under current and future potential scenarios. The impact of climate change on its potential distribution was assessed with two global climate models, the CSIRO-Mk3.0 and the MIROC-H, run with two potential, future emission scenarios (A1B and A2 published by the Intergovernmental Panel on Climate Change. We compared today’s climate situation with two arbitrarily chosen future time points (2030 and 2070 to see the impact on the worldwide distribution of A. aegypti. The model for the current global climate indicated favourable areas for the mosquito within its known distribution in tropical and subtropical areas. However, even if much of the tropics and subtropics will continue to be suitable, the climatically favourable areas for A. aegypti globally are projected to contract under the future scenarios produced by these models, while currently unfavourable areas, such as inland Australia, the Arabian Peninsula, southern Iran and some parts of North America may become climatically favourable for this mosquito species. The climate models for the Aedes dengue vector presented here should be useful for management purposes as they can be adapted for decision/making regarding allocation of resources for dengue risk toward areas where risk infection remains and away from areas where climatic suitability is likely to decrease in the future.

  20. Global Distribution of Total Inorganic Carbon and Total Alkalinity below the Deepest Winter Mixed Layer Depths

    Energy Technology Data Exchange (ETDEWEB)

    Goyet, C.; Healy, R.; Ryan, J.; Kozyr, A.

    2000-05-01

    Modeling the global ocean-atmosphere carbon dioxide system is becoming increasingly important to greenhouse gas policy. These models require initialization with realistic three-dimensional (3-D) oceanic carbon fields. This report presents an approach to establishing these initial conditions from an extensive global database of ocean carbon dioxide (CO{sub 2}) system measurements and well-developed interpolation methods.

  1. High-resolution combined global gravity field modelling: Solving large kite systems using distributed computational algorithms

    Science.gov (United States)

    Zingerle, Philipp; Fecher, Thomas; Pail, Roland; Gruber, Thomas

    2016-04-01

    One of the major obstacles in modern global gravity field modelling is the seamless combination of lower degree inhomogeneous gravity field observations (e.g. data from satellite missions) with (very) high degree homogeneous information (e.g. gridded and reduced gravity anomalies, beyond d/o 1000). Actual approaches mostly combine such data only on the basis of the coefficients, meaning that previously for both observation classes (resp. models) a spherical harmonic analysis is done independently, solving dense normal equations (NEQ) for the inhomogeneous model and block-diagonal NEQs for the homogeneous. Obviously those methods are unable to identify or eliminate effects as spectral leakage due to band limitations of the models and non-orthogonality of the spherical harmonic base functions. To antagonize such problems a combination of both models on NEQ-basis is desirable. Theoretically this can be achieved using NEQ-stacking. Because of the higher maximum degree of the homogeneous model a reordering of the coefficient is needed which leads inevitably to the destruction of the block diagonal structure of the appropriate NEQ-matrix and therefore also to the destruction of simple sparsity. Hence, a special coefficient ordering is needed to create some new favorable sparsity pattern leading to a later efficient computational solving method. Such pattern can be found in the so called kite-structure (Bosch, 1993), achieving when applying the kite-ordering to the stacked NEQ-matrix. In a first step it is shown what is needed to attain the kite-(NEQ)system, how to solve it efficiently and also how to calculate the appropriate variance information from it. Further, because of the massive computational workload when operating on large kite-systems (theoretically possible up to about max. d/o 100.000), the main emphasis is put on to the presentation of special distributed algorithms which may solve those systems parallel on an indeterminate number of processes and are

  2. Post-Apartheid South Africa: Poverty and Distribution Trends in an Era of Globalization

    OpenAIRE

    Van der Berg, Servaas; Louw, Megan; Burger, Ronelle

    2007-01-01

    South Africa’s transition to democracy in 1994 created new possibilities for economic policy. Economic liberalization brought sustained, if unspectacular, growth that reversed the long decline in per capita incomes, but left its scars in much job shedding associated with business becoming internationally competitive. This accords with international evidence that trade liberalization takes time to realize positive employment effects. Disappointing employment growth in the face of an expanding ...

  3. Collective motions of globally coupled oscillators and some probability distributions on circle

    Energy Technology Data Exchange (ETDEWEB)

    Jaćimović, Vladimir [Faculty of Natural Sciences and Mathematics, University of Montenegro, Cetinjski put, bb., 81000 Podgorica (Montenegro); Crnkić, Aladin, E-mail: aladin.crnkic@hotmail.com [Faculty of Technical Engineering, University of Bihać, Ljubijankićeva, bb., 77000 Bihać, Bosnia and Herzegovina (Bosnia and Herzegovina)

    2017-06-28

    In 2010 Kato and Jones described a new family of probability distributions on circle, obtained as Möbius transformation of von Mises distribution. We present the model demonstrating that these distributions appear naturally in study of populations of coupled oscillators. We use this opportunity to point out certain relations between Directional Statistics and collective motion of coupled oscillators. - Highlights: • We specify probability distributions on circle that arise in Kuramoto model. • We study how the mean-field coupling affects the shape of distribution of phases. • We discuss potential applications in some experiments on cell cycle. • We apply Directional Statistics to study collective dynamics of coupled oscillators.

  4. The Need for Global Application of the Accountability for Reasonableness Approach to Support Sustainable Outcomes Comment on "Expanded HTA: Enhancing Fairness and Legitimacy".

    Science.gov (United States)

    Byskov, Jens; Maluka, Stephen Oswald; Marchal, Bruno; Shayo, Elizabeth H; Bukachi, Salome; Zulu, Oseph M; Blas, Erik; Michelo, Charles; Ndawi, Benedict; Hurtig, Anna-Karin

    2016-08-15

    an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  5. Global Scale Emission and Distribution of Sea Spray Aerosol: Sea-Salt and Organic Enrichment

    OpenAIRE

    VIGNATI Elisabetta; M. C. Facchini; Rinaldi, Matteo; Scannell, Claire; Ceburnis, D; Sciare, J.; Kanakidou, M.; Myriokefalitakis, Stelios; DENTENER Franciscus; O'DOWD Colin

    2009-01-01

    The chemical composition of marine aerosols as a function of their size is an important parameter for the evaluation of their impact on the global climate system. In this work we model fine particle organic matter emitted by sea spray processes and its influence on the aerosol chemical properties at the global scale using the off-line global Chemistry-Transport Model TM5. TM5 is coupled to a microphysical aerosol dynamics model providing size resolved information on particle masses and number...

  6. Efficient use of an improved radiative transfer code to simulate near-global distributions of satellite-measured radiances.

    Science.gov (United States)

    Nakajima, Takashi Y; Murakami, Hiroshi; Hori, Masahiro; Nakajima, Teruyuki; Aoki, Teruo; Oishi, Tomohiko; Tanaka, Akihiko

    2003-06-20

    Two new extension modules that give the water-leaving radiance from the ocean and the snow bidirectional reflectance distribution function were implemented in the latest radiative transfer code. In addition, to simulate the near-global distributions of satellite-measured radiances by using the improved radiative transfer code, we tested and applied the look-up table method together with the process-separation technique of the radiative transfer calculation. The computing time was reduced from 1 year to 20 s to simulate one channel, one scene of the Global Imager image by use of an Alpha 21164A-2 (600-MHz) machine. The error analyses showed that the radiances were simulated with less than 1% error for the nonabsorbing visible channels and approximately 2% error for absorbing channels by use of this method.

  7. Development of probability distributions for regional climate change from uncertain global mean warming and an uncertain scaling relationship

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available To produce probability distributions for regional climate change in surface temperature and precipitation, a probability distribution for global mean temperature increase has been combined with the probability distributions for the appropriate scaling variables, i.e. the changes in regional temperature/precipitation per degree global mean warming. Each scaling variable is assumed to be normally distributed. The uncertainty of the scaling relationship arises from systematic differences between the regional changes from global and regional climate model simulations and from natural variability. The contributions of these sources of uncertainty to the total variance of the scaling variable are estimated from simulated temperature and precipitation data in a suite of regional climate model experiments conducted within the framework of the EU-funded project PRUDENCE, using an Analysis Of Variance (ANOVA. For the area covered in the 2001–2004 EU-funded project SWURVE, five case study regions (CSRs are considered: NW England, the Rhine basin, Iberia, Jura lakes (Switzerland and Mauvoisin dam (Switzerland. The resulting regional climate changes for 2070–2099 vary quite significantly between CSRs, between seasons and between meteorological variables. For all CSRs, the expected warming in summer is higher than that expected for the other seasons. This summer warming is accompanied by a large decrease in precipitation. The uncertainty of the scaling ratios for temperature and precipitation is relatively large in summer because of the differences between regional climate models. Differences between the spatial climate-change patterns of global climate model simulations make significant contributions to the uncertainty of the scaling ratio for temperature. However, no meaningful contribution could be found for the scaling ratio for precipitation due to the small number of global climate models in the PRUDENCE project and natural variability, which is

  8. Understanding Information Technology Investment Decision-Making in the Context of Hotel Global Distribution Systems: a Multiple-Case Study

    OpenAIRE

    Connolly, Daniel J.

    1999-01-01

    UNDERSTANDING INFORMATION TECHNOLOGY INVESTMENT DECISION-MAKING IN THE CONTEXT OF HOTEL GLOBAL DISTRIBUTION SYSTEMS: A MULTIPLE-CASE STUDY by Daniel J. Connolly Dr. Michael D. Olsen, Chair Department of Hospitality and Tourism Management ABSTRACT This study investigates what three large, multinational hospitality companies do in practice when evaluating and making IT investment decisions. This study was launched in an attempt to 1) learn more about ...

  9. FORMATION OF DISTRIBUTION SYSTEMS WITH THE INVOLVEMENT OF THE GLOBAL RETAIL CHAINS

    National Research Council Canada - National Science Library

    L. Kudyrko; I. Sevruk

    2015-01-01

    ... the author’s definition of the term “global retail chain”. The role and responsibilities of international retailers in the formation of marketing structures on international markets are discovered...

  10. Newly discovered deep-branching marine plastid lineages are numerically rare but globally distributed

    Digital Repository Service at National Institute of Oceanography (India)

    Choi, C.J.; Bachy, C.; Jaeger, G.S.; Poirier, C.; Sudek, L.; Sarma, V.V.S.S.; Mahadevan, A.; Giovannoni, S.J.; Worden, A.Z.

    on the biological communities that carry out marine photosynthesis. Phytoplankton perform half of global biological CO2 uptake, fuel marine food chains, and include diverse eukaryotic algae that have photosynthetic organelles (plastids) acquired through multiple...

  11. Cell volumes of marine phytoplankton from globally distributed coastal data sets

    Digital Repository Service at National Institute of Oceanography (India)

    Harrison, P.J.; Zingone, A.; Mickelson, M.J.; Lehtinen, S.; Ramaiah, N.; Kraberg, A.C.; Sun, J.; McQuatters-Gollop, A.; Jakobsen, H.H.

    Globally there are numerous long-term time series measuring phytoplanton abundance. With appropriate conversion factors, numerical species abundance can be expressed as biovolume and then converted to phytoplankton carbon. To-date there has been...

  12. Hourly distributions of the diffuse fraction of global solar irradiation in Cordoba (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Posadillo, R.; Lopez Luque, R. [Grupo de Investigacion de Fisica para las Energias y Recursos Renovables, Dpto. de Fisica Aplicada/UCO, Edificio C2 Campus de Rabanales, 14071 Cordoba (Spain)

    2009-02-15

    Hourly global irradiations on tilted planes are required for dimensioning PV systems. However, for most sites, only global irradiations on a horizontal plane are available, and, given that to calculate the global irradiation on inclined planes the first step is to determine the diffuse component and this is not collected, we have studied the behaviour of the diffuse component on an hourly basis. Most parametrization models for the derivation of hourly diffuse irradiance from hourly global irradiance involve the clearness index, a parameter that implicitly includes solar altitude. The present paper has focused on the possibility of also including ''mean solar altitude anti {alpha}'' explicitly as a parameter in addition to the clearness index. Several analytical models are proposed, validated and compared here, using solar data collected on our station located in Cordoba (Spain). (author)

  13. Leveraging Complementary Distribution Channels for an Effective, Efficient Global Supply Chain

    Science.gov (United States)

    2007-01-01

    their strengths , the channels become complementary elements of an effective, efficient global supply chain. The Department of Defense’s inventory...leverage their individual strengths , these channels become complementary elements of an effective, efficient global supply chain. - 3 - 2. Major...commercial premium air delivery carriers such as FedEx, DHL , and UPS through blanket contracts that are all part of the WWX program. “Surface-direct” is

  14. US Global Change Research Program Distributed Cost Budget Interagency Funds Transfer from DOE to NSF

    Energy Technology Data Exchange (ETDEWEB)

    Uhle, Maria [National Science Foundation (NSF), Washington, DC (United States)

    2016-09-22

    These funds were transferred from DOE to NSF as DOE's contribution to the U.S. Global Change Research Program in support of 4 internationalnactivities/programs as approved by the U.S. Global Change Research Program on 14 March 2014. The programs are the International Geosphere-Biosphere Programme, the DIVERSITAS programme, and the World Climate Research Program. All program awards ended as of 09-23-2015.

  15. Potential impacts of global warming on the diversity and distribution of stream insects in South Korea.

    Science.gov (United States)

    Li, Fengqing; Kwon, Yong-Su; Bae, Mi-Jung; Chung, Namil; Kwon, Tae-Sung; Park, Young-Seuk

    2014-04-01

    Globally, the East Asian monsoon region is one of the richest environments in terms of biodiversity. The region is undergoing rapid human development, yet its river ecosystems have not been well studied. Global warming represents a major challenge to the survival of species in this region and makes it necessary to assess and reduce the potential consequences of warming on species of conservation concern. We projected the effects of global warming on stream insect (Ephemeroptera, Odonata, Plecoptera, and Trichoptera [EOPT]) diversity and predicted the changes of geographical ranges for 121 species throughout South Korea. Plecoptera was the most sensitive (decrease of 71.4% in number of species from the 2000s through the 2080s) order, whereas Odonata benefited (increase of 66.7% in number of species from the 2000s through the 2080s) from the effects of global warming. The impact of global warming on stream insects was predicted to be minimal prior to the 2060s; however, by the 2080s, species extirpation of up to 20% in the highland areas and 2% in the lowland areas were predicted. The projected responses of stream insects under global warming indicated that species occupying specific habitats could undergo major reductions in habitat. Nevertheless, habitat of 33% of EOPT (including two-thirds of Odonata and one-third of Ephemeroptera, Plecoptera, and Trichoptera) was predicted to increase due to global warming. The community compositions predicted by generalized additive models varied over this century, and a large difference in community structure in the highland areas was predicted between the 2000s and the 2080s. However, stream insect communities, especially Odonata, Plecoptera, and Trichoptera, were predicted to become more homogenous under global warming. © 2013 Society for Conservation Biology.

  16. Analytical results for the time-dependent current density distribution of expanding ultracold gases after a sudden change of the confining potential

    Science.gov (United States)

    Boumaza, R.; Bencheikh, K.

    2017-12-01

    Using the so-called operator product expansion to lowest order, we extend the work in Campbell et al (2015 Phys. Rev. Lett 114 125302) by deriving a simple analytical expression for the long-time asymptotic one-body reduced density matrix during free expansion for a one-dimensional system of bosons with large atom number interacting through a repulsive delta potential initially confined by a potential well. This density matrix allows direct access to the momentum distribution and also to the mass current density. For initially confining power-law potentials we give explicit expressions, in the limits of very weak and very strong interaction, for the current density distributions during the free expansion. In the second part of the work we consider the expansion of ultracold gas from a confining harmonic trap to another harmonic trap with a different frequency. For the case of a quantum impenetrable gas of bosons (a Tonks–Girardeau gas) with a given atom number, we present an exact analytical expression for the mass current distribution (mass transport) after release from one harmonic trap to another harmonic trap. It is shown that, for a harmonically quenched Tonks–Girardeau gas, the current distribution is a suitable collective observable and under the weak quench regime, it exhibits oscillations at the same frequencies as those recently predicted for the peak momentum distribution in the breathing mode. The analysis is extended to other possible quenched systems.

  17. Influence of the elliptical and circular orifices on the local heat transfer distribution of a flat plate impinged by under-expanded jets

    Science.gov (United States)

    Vinze, Ravish; Limeye, M. D.; Prabhu, S. V.

    2017-04-01

    Experimental study is carried out to explore the influence of nozzle profile on heat transfer for underexpanded impinging jets. Circular and elliptical orifices are used to generate underexpanded jets for underexpantion ratio ranging from 1.25 to 2.67. The supply pressure maintained in the present study ranges from 2.36 to 5.08 times the ambient pressure. IR thermal imaging camera is used to measure surface temperature of thin foil at different nozzle to plate distances. Shadowgraph and pressure distribution are used to understand the flow structure and distribution of circular and elliptical nozzle. It is observed that plate shock and pressure distribution over the plate have significant influence on the local heat transfer. The performance of the circular orifice is far better at lower z/d. The axis switching is observed for an elliptical orifice. Correlation for local heat transfer predicts Nusselt number comparable within 15 % of experimental results.

  18. Mapping the Global Potential Geographical Distribution of Black Locust (Robinia Pseudoacacia L. Using Herbarium Data and a Maximum Entropy Model

    Directory of Open Access Journals (Sweden)

    Guoqing Li

    2014-11-01

    Full Text Available Black locust (Robinia pseudoacacia L. is a tree species of high economic and ecological value, but is also considered to be highly invasive. Understanding the global potential distribution and ecological characteristics of this species is a prerequisite for its practical exploitation as a resource. Here, a maximum entropy modeling (MaxEnt was used to simulate the potential distribution of this species around the world, and the dominant climatic factors affecting its distribution were selected by using a jackknife test and the regularized gain change during each iteration of the training algorithm. The results show that the MaxEnt model performs better than random, with an average test AUC value of 0.9165 (±0.0088. The coldness index, annual mean temperature and warmth index were the most important climatic factors affecting the species distribution, explaining 65.79% of the variability in the geographical distribution. Species response curves showed unimodal relationships with the annual mean temperature and warmth index, whereas there was a linear relationship with the coldness index. The dominant climatic conditions in the core of the black locust distribution are a coldness index of −9.8 °C–0 °C, an annual mean temperature of 5.8 °C–14.5 °C, a warmth index of 66 °C–168 °C and an annual precipitation of 508–1867 mm. The potential distribution of black locust is located mainly in the United States, the United Kingdom, Germany, France, the Netherlands, Belgium, Italy, Switzerland, Australia, New Zealand, China, Japan, South Korea, South Africa, Chile and Argentina. The predictive map of black locust, climatic thresholds and species response curves can provide globally applicable guidelines and valuable information for policymakers and planners involved in the introduction, planting and invasion control of this species around the world.

  19. Towards a Global Water Scarcity Risk Assessment Framework: Incorporation of Probability Distributions and Hydro-Climatic Variability

    Science.gov (United States)

    Veldkamp, T. I. E.; Wada, Y.; Aerts, J. C. J. H.; Ward, P. J.

    2016-01-01

    Changing hydro-climatic and socioeconomic conditions increasingly put pressure on fresh water resources and are expected to aggravate water scarcity conditions towards the future. Despite numerous calls for risk-based water scarcity assessments, a global-scale framework that includes UNISDR's definition of risk does not yet exist. This study provides a first step towards such a risk based assessment, applying a Gamma distribution to estimate water scarcity conditions at the global scale under historic and future conditions, using multiple climate change and population growth scenarios. Our study highlights that water scarcity risk, expressed in terms of expected annual exposed population, increases given all future scenarios, up to greater than 56.2% of the global population in 2080. Looking at the drivers of risk, we find that population growth outweigh the impacts of climate change at global and regional scales. Using a risk-based method to assess water scarcity, we show the results to be less sensitive than traditional water scarcity assessments to the use of fixed threshold to represent different levels of water scarcity. This becomes especially important when moving from global to local scales, whereby deviations increase up to 50% of estimated risk levels.

  20. Global monitoring of Salmonella serovar distribution from the World Health Organization Global Foodborne Infections Network Country Data Bank: results of quality assured laboratories from 2001 to 2007.

    Science.gov (United States)

    Hendriksen, Rene S; Vieira, Antonio R; Karlsmose, Susanne; Lo Fo Wong, Danilo M A; Jensen, Arne B; Wegener, Henrik C; Aarestrup, Frank M

    2011-08-01

    Salmonella enterica is commonly acquired from contaminated food and is an important cause of illness worldwide. Interventions are needed to control Salmonella; subtyping Salmonella by serotyping is useful for targeting such interventions. We, therefore, analyzed the global distribution of the 15 most frequently identified serovars of Salmonella isolated from humans from 2001 to 2007 in laboratories from 37 countries that participated in World Health Organization Global Foodborne Infections Network and demonstrated serotyping proficiency in the Global Foodborne Infections Network External Quality Assurance System. In all regions throughout the study period, with the exception of the Oceania and North American regions, Salmonella serovars Enteritidis and Typhimurium ranked as the most common and second most common serovar, respectively. In the North American and Oceania (Australia and New Zealand) regions, Salmonella serovar Typhimurium was the most common serovar reported, and Salmonella serovar Enteritidis was the second most common serovar. During the study period, the proportion of Salmonella isolates reported from humans that were Salmonella serovar Enteritidis was 43.5% (range: 40.6% [2007] to 44.9% [2003]), and Salmonella serovar Typhimurium was 17.1% (range: 15% [2007] to 18.9% [2001]). Salmonella serovars Newport (mainly observed in Latin and North American and European countries), Infantis (dominating in all regions), Virchow (mainly observed in Asian, European, and Oceanic countries), Hadar (profound in European countries), and Agona (intense in Latin and North American and European countries) were also frequently isolated with an overall proportion of 3.5%, 1.8%, 1.5%, 1.5%, and 0.8%, respectively. There were large differences in the most commonly isolated serovars between regions, but lesser differences between countries within the same region. The results also highlight the complexity of the global epidemiology of Salmonella and the need and importance

  1. Dynamic Consensus Algorithm Based Distributed Global Efficiency Optimization of a Droop Controlled DC Microgrid

    DEFF Research Database (Denmark)

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2014-01-01

    In a DC microgrid, several paralleled conversion systems are installed in distributed substations for transferring power from external grid to a DC microgrid. Droop control is used for the distributed load sharing among all the DC/DC converters. Considering the typical efficiency feature of power...

  2. Global Distribution and Variability of Surface Skin and Surface Air Temperatures as Depicted in the AIRS Version-6 Data Set

    Science.gov (United States)

    Susskind, Joel; Lee, Jae N.; Iredell, Lena

    2014-01-01

    In this presentation, we will briefly describe the significant improvements made in the AIRS Version-6 retrieval algorithm, especially as to how they affect retrieved surface skin and surface air temperatures. The global distribution of seasonal 1:30 AM and 1:30 PM local time 12 year climatologies of Ts,a will be presented for the first time. We will also present the spatial distribution of short term 12 year anomaly trends of Ts,a at 1:30 AM and 1:30 PM, as well as the spatial distribution of temporal correlations of Ts,a with the El Nino Index. It will be shown that there are significant differences between the behavior of 1:30 AM and 1:30 PM Ts,a anomalies in some arid land areas.

  3. Global Climate Change Effects on Venezuela's Vulnerability to Chagas Disease is Linked to the Geographic Distribution of Five Triatomine Species.

    Science.gov (United States)

    Ceccarelli, Soledad; Rabinovich, Jorge E

    2015-11-01

    We analyzed the possible effects of global climate change on the potential geographic distribution in Venezuela of five species of triatomines (Eratyrus mucronatus (Stal, 1859), Panstrongylus geniculatus (Latreille, 1811), Rhodnius prolixus (Stål, 1859), Rhodnius robustus (Larrousse, 1927), and Triatoma maculata (Erichson, 1848)), vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. To obtain the future potential geographic distributions, expressed as climatic niche suitability, we modeled the presences of these species using two IPCC (Intergovernmental Panel on Climate Change) future emission scenarios of global climate change (A1B and B1), the Global Climate model CSIRO Mark 3.0, and three periods of future projections (years 2020, 2060, and 2080). After estimating with the MaxEnt software the future climatic niche suitability for each species, scenario, and period of future projections, we estimated a series of indexes of Venezuela's vulnerability at the county, state, and country level, measured as the number of people exposed due to the changes in the geographical distribution of the five triatomine species analyzed. Despite that this is not a measure of the risk of Chagas disease transmission, we conclude that possible future effects of global climate change on the Venezuelan population vulnerability show a slightly decreasing trend, even taking into account future population growth; we can expect fewer locations in Venezuela where an average Venezuelan citizen would be exposed to triatomines in the next 50-70 yr. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Environmental boundaries of marine cladoceran distributions in the NW Mediterranean: Implications for their expansion under global warming

    KAUST Repository

    Atienza, Dacha

    2016-08-10

    We studied the horizontal and vertical distributions of marine cladocerans across the Catalan Sea shelf (NW Mediterranean) in July and September 2003, and in June and July 2004. At the seasonal scale, Penilia avirostris appears first in June in the southern region, where temperatures are warmer, and its populations develop northward during the summer. Evadne-Pseudevadne did not show a clear pattern, likely because several species were pooled. In 2003 successive heat waves affecting southwestern Europe resulted in surface seawater temperatures about 2 °C higher than usual across the whole study region. These high temperatures were associated with much lower abundance of P. avirostris. Overall, the mesoscale distributions of cladocerans were associated with the presence of low salinity, productive and stratified waters of continental origin, and negatively linked to the intrusion of offshore waters. On the vertical scale P. avirostris was located within or above the thermocline, whereas Evadne-Pseudevadne was much shallower; no evidence of diel migration was detected in either group. Our study provides new insights regarding the environmental limits for marine cladocerans in the NW Mediterranean; in the particular case of P. avirostris that knowledge can define the likely boundaries of its new distributions as it expands poleward under climate change. © 2016 Elsevier B.V.

  5. Environmental boundaries of marine cladoceran distributions in the NW Mediterranean: Implications for their expansion under global warming

    Science.gov (United States)

    Atienza, Dacha; Sabatés, Ana; Isari, Stamatina; Saiz, Enric; Calbet, Albert

    2016-12-01

    We studied the horizontal and vertical distributions of marine cladocerans across the Catalan Sea shelf (NW Mediterranean) in July and September 2003, and in June and July 2004. At the seasonal scale, Penilia avirostris appears first in June in the southern region, where temperatures are warmer, and its populations develop northward during the summer. Evadne-Pseudevadne did not show a clear pattern, likely because several species were pooled. In 2003 successive heat waves affecting southwestern Europe resulted in surface seawater temperatures about 2 °C higher than usual across the whole study region. These high temperatures were associated with much lower abundance of P. avirostris. Overall, the mesoscale distributions of cladocerans were associated with the presence of low salinity, productive and stratified waters of continental origin, and negatively linked to the intrusion of offshore waters. On the vertical scale P. avirostris was located within or above the thermocline, whereas Evadne-Pseudevadne was much shallower; no evidence of diel migration was detected in either group. Our study provides new insights regarding the environmental limits for marine cladocerans in the NW Mediterranean; in the particular case of P. avirostris that knowledge can define the likely boundaries of its new distributions as it expands poleward under climate change.

  6. Global distribution of N2O emissions from aquatic systems : natural emissions and anthropogenic effects

    NARCIS (Netherlands)

    Seitzinger, S.P.; Styles, R.V.; Kroeze, C.

    2000-01-01

    Context Abstract: Atmospheric concentrations of nitrous oxide, a greenhouse gas, are increasing due to human activities. Our analysis suggests that a third of global anthropogenic N2O emission is from aquatic sources (rivers, estuaries, continental shelves) and the terrestrial sources comprise the

  7. Terrestrial gross carbon dioxide uptake : Global distribution and covariation with climate

    NARCIS (Netherlands)

    Beer, Christian; Reichstein, Markus; Tomelleri, Enrico; Ciais, Philippe; Jung, Martin; Carvalhais, Nuno; Rödenbeck, Christian; Arain, M. Altaf; Baldocchi, Dennis D.; Bonan, Gordon B.; Bondeau, Alberte; Cescatti, Alessandro; Lasslop, Gitta; Lindroth, Anders; Lomas, Mark; Luyssaert, Sebastiaan; Margolis, Hank; Oleson, Keith W.; Roupsard, Olivier; Veenendaal, Elmar; Viovy, Nicolas; Williams, Christopher M.; Woodward, F. Ian; Papale, Dario

    2010-01-01

    Terrestrial gross primary production (GPP) is the largest global CO 2 flux driving several ecosystem functions. We provide an observation-based estimate of this flux at 123 ± 8 petagrams of carbon per year (Pg C year-1) using eddy covariance flux data and various diagnostic models. Tropical forests

  8. Terrestrial gross carbon dioxide uptake: Global distribution and covariation with climate

    NARCIS (Netherlands)

    Beer, C.; Veenendaal, E.M.

    2010-01-01

    Terrestrial gross primary production (GPP) is the largest global CO2 flux driving several ecosystem functions. We provide an observation-based estimate of this flux at 123 ± 8 petagrams of carbon per year (Pg C year-1) using eddy covariance flux data and various diagnostic models. Tropical forests

  9. Global distribution of dissolved organic matter along the aquatic continuum: Across rivers, lakes and oceans

    DEFF Research Database (Denmark)

    Massicotte, Philippe; Asmala, Eero; Stedmon, Colin

    2017-01-01

    and transformation of dissolved organic matter (DOM) along the aquatic continuum across rivers and lakes to oceans. A strong log-linear relationship (R2 = 0.92) between DOC concentration and CDOM absorption at 350 nm was observed at a global scale, but was found to be ecosystem-dependent at local and regional...

  10. Global prevalence and genotype distribution of hepatitis C virus infection in 2015

    DEFF Research Database (Denmark)

    Christensen, Peer Brehm

    2017-01-01

    BACKGROUND: The 69th World Health Assembly approved the Global Health Sector Strategy to eliminate hepatitis C virus (HCV) infection by 2030, which can become a reality with the recent launch of direct acting antiviral therapies. Reliable disease burden estimates are required for national...

  11. Can agile software tools bring the benefits of a task board to globally distributed teams?

    NARCIS (Netherlands)

    Katsma, Christiaan; Amrit, Chintan Amrit; van Hillegersberg, Jos; Sikkel, Nicolaas; Oshri, Ilan; Kotlarsky, Julia; Willcocks, Leslie P.

    Software-based tooling has become an essential part of globally disitrbuted software development. In this study we focus on the usage of such tools and task boards in particular. We investigate the deployment of these tools through a field research in 4 different companies that feature agile and

  12. CracidMex1: a comprehensive database of global occurrences of cracids (Aves, Galliformes) with distribution in Mexico.

    Science.gov (United States)

    Pinilla-Buitrago, Gonzalo; Martínez-Morales, Miguel Angel; González-García, Fernando; Enríquez, Paula L; Rangel-Salazar, José Luis; Romero, Carlos Alberto Guichard; Navarro-Sigüenza, Adolfo G; Monterrubio-Rico, Tiberio César; Escalona-Segura, Griselda

    2014-01-01

    Cracids are among the most vulnerable groups of Neotropical birds. Almost half of the species of this family are included in a conservation risk category. Twelve taxa occur in Mexico, six of which are considered at risk at national level and two are globally endangered. Therefore, it is imperative that high quality, comprehensive, and high-resolution spatial data on the occurrence of these taxa are made available as a valuable tool in the process of defining appropriate management strategies for conservation at a local and global level. We constructed the CracidMex1 database by collating global records of all cracid taxa that occur in Mexico from available electronic databases, museum specimens, publications, "grey literature", and unpublished records. We generated a database with 23,896 clean, validated, and standardized geographic records. Database quality control was an iterative process that commenced with the consolidation and elimination of duplicate records, followed by the geo-referencing of records when necessary, and their taxonomic and geographic validation using GIS tools and expert knowledge. We followed the geo-referencing protocol proposed by the Mexican National Commission for the Use and Conservation of Biodiversity. We could not estimate the geographic coordinates of 981 records due to inconsistencies or lack of sufficient information in the description of the locality. Given that current records for most of the taxa have some degree of distributional bias, with redundancies at different spatial scales, the CracidMex1 database has allowed us to detect areas where more sampling effort is required to have a better representation of the global spatial occurrence of these cracids. We also found that particular attention needs to be given to taxa identification in those areas where congeners or conspecifics co-occur in order to avoid taxonomic uncertainty. The construction of the CracidMex1 database represents the first comprehensive research effort to

  13. CracidMex1: a comprehensive database of global occurrences of cracids (Aves, Galliformes) with distribution in Mexico

    Science.gov (United States)

    Pinilla-Buitrago, Gonzalo; Martínez-Morales, Miguel Angel; González-García, Fernando; Enríquez, Paula L.; Rangel-Salazar, José Luis; Romero, Carlos Alberto Guichard; Navarro-Sigüenza, Adolfo G.; Monterrubio-Rico, Tiberio César; Escalona-Segura, Griselda

    2014-01-01

    Abstract Cracids are among the most vulnerable groups of Neotropical birds. Almost half of the species of this family are included in a conservation risk category. Twelve taxa occur in Mexico, six of which are considered at risk at national level and two are globally endangered. Therefore, it is imperative that high quality, comprehensive, and high-resolution spatial data on the occurrence of these taxa are made available as a valuable tool in the process of defining appropriate management strategies for conservation at a local and global level. We constructed the CracidMex1 database by collating global records of all cracid taxa that occur in Mexico from available electronic databases, museum specimens, publications, “grey literature”, and unpublished records. We generated a database with 23,896 clean, validated, and standardized geographic records. Database quality control was an iterative process that commenced with the consolidation and elimination of duplicate records, followed by the geo-referencing of records when necessary, and their taxonomic and geographic validation using GIS tools and expert knowledge. We followed the geo-referencing protocol proposed by the Mexican National Commission for the Use and Conservation of Biodiversity. We could not estimate the geographic coordinates of 981 records due to inconsistencies or lack of sufficient information in the description of the locality. Given that current records for most of the taxa have some degree of distributional bias, with redundancies at different spatial scales, the CracidMex1 database has allowed us to detect areas where more sampling effort is required to have a better representation of the global spatial occurrence of these cracids. We also found that particular attention needs to be given to taxa identification in those areas where congeners or conspecifics co-occur in order to avoid taxonomic uncertainty. The construction of the CracidMex1 database represents the first comprehensive

  14. Global migration and the changing distribution of sickle haemoglobin: a quantitative study of temporal trends between 1960 and 2000.

    Science.gov (United States)

    Piel, Frédéric B; Tatem, Andrew J; Huang, Zhuojie; Gupta, Sunetra; Williams, Thomas N; Weatherall, David J

    2014-02-01

    Changes in the geographical distribution of genetic disorders are often thought to happen slowly, especially when compared with infectious diseases. Whereas mutations, genetic drift, and natural selection take place over many generations, epidemics can spread through large populations within a few days or weeks. Nevertheless, population movements can interfere with these processes, and few studies have been done of their eff ect on genetic disorders. We aimed to investigate the eff ect of global migration on the distribution of the sickle-cell gene-the most common and clinically significant haemoglobin structural variant. For each country, we extracted data from the World Bank’s Global Bilateral Migration Database about international human migrations between 1960 and 2000. We combined this information with evidence-based estimates of national HbS allele frequencies, generated within a Bayesian geostatistical framework, to analyse temporal changes in the net numbers of migrants, and classified countries with an index summarising these temporal trends. The number of international migrants increased from 92.6 million in 1960, to 165.2 million in 2000. The estimated global number of migrants with HbS increased from about 1.6 million in 1960, to 3.6 million in 2000. This increase was largely due to an increase in the number of migrants from countries with HbS allele frequencies higher than 10%, from 3.1 million in 1960, to 14.2 million in 2000. Additionally, the mean number of countries of origin for each destination country increased from 70 (SE 46) in 1960, to 98 (48) in 2000, showing an increasing diversity in the network of international migrations between countries. Our index of change map shows a patchy distribution of the magnitude of temporal changes, with the highest positive and negative values scattered across all continents. Global human population movements have had a substantial eff ect on the distribution of the HbS gene. Population movements can create

  15. The geographical distribution of fossil fuels unused when limiting global warming to 2 °C

    Science.gov (United States)

    McGlade, Christophe; Ekins, Paul

    2015-01-01

    Policy makers have generally agreed that the average global temperature rise caused by greenhouse gas emissions should not exceed 2 °C above the average global temperature of pre-industrial times. It has been estimated that to have at least a 50 per cent chance of keeping warming below 2 °C throughout the twenty-first century, the cumulative carbon emissions between 2011 and 2050 need to be limited to around 1,100 gigatonnes of carbon dioxide (Gt CO2). However, the greenhouse gas emissions contained in present estimates of global fossil fuel reserves are around three times higher than this, and so the unabated use of all current fossil fuel reserves is incompatible with a warming limit of 2 °C. Here we use a single integrated assessment model that contains estimates of the quantities, locations and nature of the world's oil, gas and coal reserves and resources, and which is shown to be consistent with a wide variety of modelling approaches with different assumptions, to explore the implications of this emissions limit for fossil fuel production in different regions. Our results suggest that, globally, a third of oil reserves, half of gas reserves and over 80 per cent of current coal reserves should remain unused from 2010 to 2050 in order to meet the target of 2 °C. We show that development of resources in the Arctic and any increase in unconventional oil production are incommensurate with efforts to limit average global warming to 2 °C. Our results show that policy makers' instincts to exploit rapidly and completely their territorial fossil fuels are, in aggregate, inconsistent with their commitments to this temperature limit. Implementation of this policy commitment would also render unnecessary continued substantial expenditure on fossil fuel exploration, because any new discoveries could not lead to increased aggregate production.

  16. Global impacts of the meat trade on in-stream organic river pollution: the importance of spatially distributed hydrological conditions

    Science.gov (United States)

    Wen, Yingrong; Schoups, Gerrit; van de Giesen, Nick

    2018-01-01

    In many regions of the world, intensive livestock farming has become a significant source of organic river pollution. As the international meat trade is growing rapidly, the environmental impacts of meat production within one country can occur either domestically or internationally. The goal of this paper is to quantify the impacts of the international meat trade on global organic river pollution at multiple scales (national, regional and gridded). Using the biological oxygen demand (BOD) as an overall indicator of organic river pollution, we compute the spatially distributed organic pollution in global river networks with and without a meat trade, where the without-trade scenario assumes that meat imports are replaced by local production. Our analysis reveals a reduction in the livestock population and production of organic pollutants at the global scale as a result of the international meat trade. However, the actual environmental impact of trade, as quantified by in-stream BOD concentrations, is negative; i.e. we find a slight increase in polluted river segments. More importantly, our results show large spatial variability in local (grid-scale) impacts that do not correlate with local changes in BOD loading, which illustrates: (1) the significance of accounting for the spatial heterogeneity of hydrological processes along river networks, and (2) the limited value of looking at country-level or global averages when estimating the actual impacts of trade on the environment.

  17. The health effects of exposure to arsenic-contaminated drinking water: a review by global geographical distribution.

    Science.gov (United States)

    Huang, Lei; Wu, Haiyun; van der Kuijp, Tsering Jan

    2015-01-01

    Chronic arsenic exposure through drinking water has been a vigorously studied and debated subject. However, the existing literature does not allow for a thorough examination of the potential regional discrepancies that may arise among arsenic-related health outcomes. The purpose of this article is to provide an updated review of the literature on arsenic exposure and commonly discussed health effects according to global geographical distribution. This geographically segmented approach helps uncover the discrepancies in the health effects of arsenic. For instance, women are more susceptible than men to a few types of cancer in Taiwan, but not in other countries. Although skin cancer and arsenic exposure correlations have been discovered in Chile, Argentina, the United States, and Taiwan, no evident association was found in mainland China. We then propose several globally applicable recommendations to prevent and treat the further spread of arsenic poisoning and suggestions of future study designs and decision-making.

  18. How Social Software Supports Cooperative Practices in a Globally Distributed Software Project

    DEFF Research Database (Denmark)

    Giuffrida, Rosalba; Dittrich, Yvonne

    2014-01-01

    In Global Software Development (GSD), the lack of face- to-face communication is a major challenge and effective computer-mediated practices are necessary. This paper analyzes cooperative practices supported by Social Software (SoSo) in a GSD student project. The empirical results show...... that the role of SoSo is to support informal communication, enabling social talks and metawork, both necessary for establishing and for maintaining effective coordination mechanisms, thus successful cooperation....

  19. A data and information system for processing, archival, and distribution of data for global change research

    Science.gov (United States)

    Graves, Sara J.

    1994-01-01

    Work on this project was focused on information management techniques for Marshall Space Flight Center's EOSDIS Version 0 Distributed Active Archive Center (DAAC). The centerpiece of this effort has been participation in EOSDIS catalog interoperability research, the result of which is a distributed Information Management System (IMS) allowing the user to query the inventories of all the DAAC's from a single user interface. UAH has provided the MSFC DAAC database server for the distributed IMS, and has contributed to definition and development of the browse image display capabilities in the system's user interface. Another important area of research has been in generating value-based metadata through data mining. In addition, information management applications for local inventory and archive management, and for tracking data orders were provided.

  20. nCTEQ15 - Global analysis of nuclear parton distributions with uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Kusina, A. [LPSC, Grenoble (France); Kovarik, K. [Munster Univ., ITP (Germany); Jezo, T. [INFN, Milan Bicocca (Italy); Clark, D. B. [Southern Methodist Univ., Dallas, TX (United States); Keppel, C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Lyonnet, F. [Southern Methodist Univ., Dallas, TX (United States); Morfin, J. G. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Olness, F. I. [Southern Methodist Univ., Dallas, TX (United States); Owens, J. F. [Florida State Univ., Tallahassee, FL (United States); Schienbein, I. [LPSC, Grenoble (France); Yu, J. Y. [Southern Methodist Univ., Dallas, TX (United States)

    2015-09-04

    We present the first official release of the nCTEQ nuclear parton distribution functions with errors. The main addition to the previous nCTEQ PDFs is the introduction of PDF uncertainties based on the Hessian method. Another important addition is the inclusion of pion production data from RHIC that give us a handle on constraining the gluon PDF. This contribution summarizes our results from arXiv:1509.00792, and concentrates on the comparison with other groups providing nuclear parton distributions.

  1. nCTEQ15 - Global analysis of nuclear parton distributions with uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Kusina, A. [Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3, Grenoble (France); Kovarik, Karol [Institut für Theoretische Physik, Westfälische Wilhelms-Universität Münster, Münster (Germany); Jezo, T. [Università di Milano-Bicocca and INFN, Sezione di Milano-Bicocca, Milano (Italy); Clark, D. B. [Southern Methodist Univ., Dallas, TX (United States); Keppel, Cynthia [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Lyonnet, F. [Southern Methodist Univ., Dallas, TX (United States); Morfin, Jorge [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Olness, F. I. [Southern Methodist Univ., Dallas, TX (United States); Owens, Jeff [Florida State Univ., Tallahassee, FL (United States). Dept. of Physics; Schienbein, I. [Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3, Grenoble (France); Yu, J. Y. [Southern Methodist Univ., Dallas, TX (United States)

    2015-09-01

    We present the first official release of the nCTEQ nuclear parton distribution functions with errors. The main addition to the previous nCTEQ PDFs is the introduction of PDF uncertainties based on the Hessian method. Another important addition is the inclusion of pion production data from RHIC that give us a handle on constraining the gluon PDF. This contribution summarizes our results from arXiv:1509.00792 and concentrates on the comparison with other groups providing nuclear parton distributions.

  2. Long-Term Global Distributions of Mesoscale Variations in Atmospheric Radio Refraction Obtained from the GPS Champ Satellite Data

    Science.gov (United States)

    Gavrilov, N. M.; Manuilova, R. O.

    2016-12-01

    We obtain average global distributions of the variances of the mesoscale variations in the atmospheric radio-refraction index (refractive index) at altitudes of 5-35 km from the data of the radio-occultation experiments performed during operation of the low-orbit GPS CHAMP satellite in the period 2001-2009. The filtering of the vertical profiles of the radio-refraction index allows one to determine the variances of the variations with vertical scales below 8 km. The latitudinal-temporal distributions of the zonal-mean variances of the index demonstrate significant interannual variations at various altitudes. Seasonal variations in the variances of radio refraction are studied. Quasi-biennial oscillations at low latitudes are revealed. Acoustic-gravity waves and turbulent and convective motions in the atmosphere can cause a spread of the radio-refraction index.

  3. What Expands in an Expanding Universe?

    Directory of Open Access Journals (Sweden)

    JOSÉ A. DE FREITAS PACHECO

    2015-12-01

    Full Text Available ABSTRACT In the present investigation, the possible effects of the expansion of the Universe on systems bonded either by gravitational or electromagnetic forces, are reconsidered. It will be shown that the acceleration (positive or negative of the expanding background, is the determinant factor affecting planetary orbits and atomic sizes. In the presently accepted cosmology (ΛCDM all bonded systems are expanding at a decreasing rate that tends to be zero as the universe enters in a de Sitter phase. It is worth mentioning that the estimated expansion rates are rather small and they can be neglected for all practical purposes.

  4. What Expands in an Expanding Universe?

    Science.gov (United States)

    Pacheco, José A De Freitas

    2015-01-01

    In the present investigation, the possible effects of the expansion of the Universe on systems bonded either by gravitational or electromagnetic forces, are reconsidered. It will be shown that the acceleration (positive or negative) of the expanding background, is the determinant factor affecting planetary orbits and atomic sizes. In the presently accepted cosmology (ΛCDM) all bonded systems are expanding at a decreasing rate that tends to be zero as the universe enters in a de Sitter phase. It is worth mentioning that the estimated expansion rates are rather small and they can be neglected for all practical purposes.

  5. The influence of natural and anthropogenic secondary sources on the glyoxal global distribution

    Directory of Open Access Journals (Sweden)

    S. Myriokefalitakis

    2008-08-01

    Full Text Available Glyoxal, the smallest dicarbonyl, which has recently been observed from space, is expected to provide indications on volatile organic compounds (VOC oxidation and secondary aerosol formation in the troposphere. Glyoxal (CHOCHO is known to be mostly of natural origin and is produced during biogenic VOC oxidation. However, a number of anthropogenically emitted hydrocarbons, like acetylene and aromatics, have been positively identified as CHOCHO precursors. The present study investigates the contribution of pollution to the CHOCHO levels by taking into account the secondary chemical formation of CHOCHO from precursors emitted from biogenic, anthropogenic and biomass burning sources. The impact of potential primary land emissions of CHOCHO is also investigated. A global 3-dimensional chemistry transport model of the troposphere (TM4-ECPL able to simulate the gas phase chemistry coupled with all major aerosol components is used.

    The secondary anthropogenic contribution from fossil fuel and industrial VOCs emissions oxidation to the CHOCHO columns is found to reach 20–70% in the industrialized areas of the Northern Hemisphere and 3–20% in the tropics. This secondary CHOCHO source is on average three times larger than that from oxidation of VOCs from biomass burning sources. The chemical production of CHOCHO is calculated to equal to about 56 Tg y−1 with 70% being produced from biogenic hydrocarbons oxidation, 17% from acetylene, 11% from aromatic chemistry and 2% from ethene and propene. CHOCHO is destroyed in the troposphere primarily by reaction with OH radicals (23% and by photolysis (63%, but it is also removed from the atmosphere through wet (8% and dry deposition (6%. Potential formation of secondary organic aerosol through CHOCHO losses on/in aerosols and clouds is neglected here due to the significant uncertainties associated with the underlying chemistry. The global annual mean CHOCHO burden and lifetime in the model

  6. Morphology and distribution of the cave knifefish Eigenmannia vicentespelaea Triques, 1996 (Gymnotiformes: Sternopygidae from Central Brazil, with an expanded diagnosis and comments on subterranean evolution

    Directory of Open Access Journals (Sweden)

    Maria Elina Bichuette

    Full Text Available We present herein data on morphology and distribution of the cave knifefish Eigenmannia vicentespelaea Triques, 1996, from the São Domingos karst area, Central Brazil, comparing it to the epigean (surface species, Eigenmannia sp., found in the same area (but not syntopic with E. vicentespelaea and also with congeners from other localities. Collecting sites comprising epigean and subterranean stream reaches in São Domingos were sampled during the dry seasons of 1999, 2000, and 2001 using several methods. Preserved specimens of E. vicentespelaea (n=25, including holotype and paratype and of Eigenmannia sp. (n=15 were compared with focus on morphometric characters, body pigmentation and eye condition. A combination of characters separates E. vicentespelaea from Eigenmannia sp. and other congeners: the length from the tip of the snout to the posterior of the anal fin base, ocular diameter: head length and pre-anal distance: head length proportions, and body pigmentation. A wider morphometric variation in E. vicentespelaea is described than that reported in the original description (based on two specimens.

  7. Determining global distribution of microplastics by combining citizen science and in-depth case studies.

    Science.gov (United States)

    Bosker, Thijs; Behrens, Paul; Vijver, Martina G

    2017-05-01

    Microplastics (microplastics levels. The difference in extraction procedures can especially impact study outcomes, making it difficult, and sometimes impossible, to directly compare results among studies. To address this, we recently developed a standard operating procedure (SOP) for sampling microplastics on beaches. We are now assessing regional and global variations in beach microplastics using this standardized approach for 2 research projects. Our first project involves the general public through citizen science. Participants collect sand samples from beaches using a basic protocol, and we subsequently extract and quantify microplastics in a central laboratory using the SOP. Presently, we have 80+ samples from around the world and expect this number to further increase. Second, we are conducting 2, in-depth, regional case studies: one along the Dutch coast (close to major rivers, a known source of microplastic input into marine systems), and the other on the Lesser Antilles in the Caribbean (in the proximity to a hotspot of plastics in the North Atlantic Ocean). In both projects, we use our new SOP to determine regional variation in microplastics, including differences in physicochemical characteristics such as size, shape, and polymer type. Our research will provide, for the first time, a systematic comparison on levels of microplastics on beaches at both a regional and global scale. Integr Environ Assess Manag 2017;13:536-541. © 2017 SETAC. © 2017 SETAC.

  8. The global distribution of plant species richness in a human-dominated world

    Directory of Open Access Journals (Sweden)

    Katharina Gerstner

    2017-04-01

    Full Text Available Plant species richness is essential for ecosystem functioning, resilience and ecosystem services, yet is globally threatened by anthropogenic land use, including management and modification of the natural environment. At broad scales, land-use effects are often simply modelled by habitat loss, assuming that transformed land becomes completely inhospitable for naturally occurring species. Further, estimates of species losses are flawed by the common assumption of a universal slope of the species–area curve, typically ranging from 0.15 to 0.35. My PhD dissertation consists of a global species–area analysis, a meta-analysis about land-use effects on plant species richness and an approach to integrate these land-use effects in a countryside species–area model. Overall, my PhD research contributes to a deeper understanding of species–area relationships and how patterns of species richness at macroscales are driven by land use. It proposes a model to predict species richness patterns of vascular plants that overcomes limitations of previous models.

  9. Distribution and drivers of global mangrove forest change, 1996–2010

    Science.gov (United States)

    Thomas, Nathan; Lucas, Richard; Bunting, Peter; Hardy, Andrew; Rosenqvist, Ake; Simard, Marc

    2017-01-01

    For the period 1996-2010, we provide the first indication of the drivers behind mangrove land cover and land use change across the (pan-)tropics using time-series Japanese Earth Resources Satellite (JERS-1) Synthetic Aperture Radar (SAR) and Advanced Land Observing Satellite (ALOS) Phased Array-type L-band SAR (PALSAR) data. Multi-temporal radar mosaics were manually interpreted for evidence of loss and gain in forest extent and its associated driver. Mangrove loss as a consequence of human activities was observed across their entire range. Between 1996-2010 12% of the 1168 1°x1° radar mosaic tiles examined contained evidence of mangrove loss, as a consequence of anthropogenic degradation, with this increasing to 38% when combined with evidence of anthropogenic activity prior to 1996. The greatest proportion of loss was observed in Southeast Asia, whereby approximately 50% of the tiles in the region contained evidence of mangrove loss, corresponding to 18.4% of the global mangrove forest tiles. Southeast Asia contained the greatest proportion (33.8%) of global mangrove forest. The primary driver of anthropogenic mangrove loss was found to be the conversion of mangrove to aquaculture/agriculture, although substantial advance of mangroves was also evident in many regions. PMID:28594908

  10. Distribution and drivers of global mangrove forest change, 1996-2010.

    Science.gov (United States)

    Thomas, Nathan; Lucas, Richard; Bunting, Peter; Hardy, Andrew; Rosenqvist, Ake; Simard, Marc

    2017-01-01

    For the period 1996-2010, we provide the first indication of the drivers behind mangrove land cover and land use change across the (pan-)tropics using time-series Japanese Earth Resources Satellite (JERS-1) Synthetic Aperture Radar (SAR) and Advanced Land Observing Satellite (ALOS) Phased Array-type L-band SAR (PALSAR) data. Multi-temporal radar mosaics were manually interpreted for evidence of loss and gain in forest extent and its associated driver. Mangrove loss as a consequence of human activities was observed across their entire range. Between 1996-2010 12% of the 1168 1°x1° radar mosaic tiles examined contained evidence of mangrove loss, as a consequence of anthropogenic degradation, with this increasing to 38% when combined with evidence of anthropogenic activity prior to 1996. The greatest proportion of loss was observed in Southeast Asia, whereby approximately 50% of the tiles in the region contained evidence of mangrove loss, corresponding to 18.4% of the global mangrove forest tiles. Southeast Asia contained the greatest proportion (33.8%) of global mangrove forest. The primary driver of anthropogenic mangrove loss was found to be the conversion of mangrove to aquaculture/agriculture, although substantial advance of mangroves was also evident in many regions.

  11. Global Assessment of Seasonal Potential Distribution of Mediterranean Fruit Fly, Ceratitis capitata (Diptera: Tephritidae)

    Science.gov (United States)

    Szyniszewska, Anna M.; Tatem, Andrew J.

    2014-01-01

    The Mediterranean fruit fly (Medfly) is one of the world's most economically damaging pests. It displays highly seasonal population dynamics, and the environmental conditions suitable for its abundance are not constant throughout the year in most places. An extensive literature search was performed to obtain the most comprehensive data on the historical and contemporary spatio-temporal occurrence of the pest globally. The database constructed contained 2328 unique geo-located entries on Medfly detection sites from 43 countries and nearly 500 unique localities, as well as information on hosts, life stages and capture method. Of these, 125 localities had information on the month when Medfly was recorded and these data were complemented by additional material found in comprehensive databases available online. Records from 1980 until present were used for medfly environmental niche modeling. Maximum Entropy Algorithm (MaxEnt) and a set of seasonally varying environmental covariates were used to predict the fundamental niche of the Medfly on a global scale. Three seasonal maps were also produced: January-April, May-August and September-December. Models performed significantly better than random achieving high accuracy scores, indicating a good discrimination of suitable versus unsuitable areas for the presence of the species. PMID:25375649

  12. Rapid upslope shifts in New Guinean birds illustrate strong distributional responses of tropical montane species to global warming

    Science.gov (United States)

    Freeman, Benjamin G.; Class Freeman, Alexandra M.

    2014-01-01

    Temperate-zone species have responded to warming temperatures by shifting their distributions poleward and upslope. Thermal tolerance data suggests that tropical species may respond to warming temperatures even more strongly than temperate-zone species, but this prediction has yet to be tested. We addressed this data gap by conducting resurveys to measure distributional responses to temperature increases in the elevational limits of the avifaunas of two geographically and faunally independent New Guinean mountains, Mt. Karimui and Karkar Island, 47 and 44 y after they were originally surveyed. Although species richness is roughly five times greater on mainland Mt. Karimui than oceanic Karkar Island, distributional shifts at both sites were similar: upslope shifts averaged 113 m (Mt. Karimui) and 152 m (Karkar Island) for upper limits and 95 m (Mt. Karimui) and 123 m (Karkar Island) for lower limits. We incorporated these results into a metaanalysis to compare distributional responses of tropical species with those of temperate-zone species, finding that average upslope shifts in tropical montane species match local temperature increases significantly more closely than in temperate-zone montane species. That tropical species appear to be strong responders has global conservation implications and provides empirical support to hitherto untested models that predict widespread extinctions in upper-elevation tropical endemics with small ranges. PMID:24550460

  13. Diversity and distribution of the Gastropoda Opisthobranchia from the Atlantic Ocean: A global biogeographic approach

    Directory of Open Access Journals (Sweden)

    Francisco J. García

    2009-03-01

    Full Text Available A zoogeographic study of the Opisthobranchia (Mollusca, Gastropoda from the Atlantic Ocean was carried out. Data on Opisthobranch occurrence were collated from literature records and databases. An estimated 1066 species were considered for this study, which belonged to the orders Cephalaspidea, Anaspidea, Sacoglossa, Notaspidea and Nudibranchia. Biogeographical patterns were analysed using cluster analysis (TWINSPAN and ordination MDS (non-metric multidimensional scaling program. The richness of opisthobranchs increases from polar to tropical regions along Atlantic shores. The cluster analysis showed that there is a latitudinal and longitudinal separation of the biogeographical areas. The amphiatlantic species can be separated into four groups according to their distribution: G1.1.- the geographic range of species is limited to cold water on both sides of the Atlantic; G1.2.- species with geographic ranges limited to the western Arctic and Boreal regions, with a wide distribution in the eastern Atlantic, from the eastern Arctic or the eastern Boreal region to the Lusitanian and Mediterranean provinces; G2.1.- species with geographic ranges limited to the Caribbean and Mauritanian-Senegalese areas; G2.2.- species with a wide geographical distribution along both Atlantic shores.

  14. The Impact of Global Climate Change on the Geographic Distribution and Sustainable Harvest of Hancornia speciosa Gomes (Apocynaceae) in Brazil

    Science.gov (United States)

    Nabout, João Carlos; Magalhães, Mara Rúbia; de Amorim Gomes, Marcos Aurélio; da Cunha, Hélida Ferreira

    2016-04-01

    The global Climate change may affect biodiversity and the functioning of ecosystems by changing the appropriate locations for the development and establishment of the species. The Hancornia speciosa, popularly called Mangaba, is a plant species that has potential commercial value and contributes to rural economic activities in Brazil. The aim of this study was to evaluate the impact of global climate change on the potential geographic distribution, productivity, and value of production of H. speciosa in Brazil. We used MaxEnt to estimate the potential geographic distribution of the species in current and future (2050) climate scenarios. We obtained the productivity and value of production for 74 municipalities in Brazil. Moreover, to explain the variation the productivity and value of production, we constructed 15 models based on four variables: two ecological (ecological niche model and the presence of Unity of conservation) and two socio-economic (gross domestic product and human developed index). The models were selected using Akaike Information Criteria. Our results suggest that municipalities currently harvesting H. speciosa will have lower harvest rates in the future (mainly in northeastern Brazil). The best model to explain the productivity was ecological niche model; thus, municipalities with higher productivity are inserted in regions with higher environmental suitability (indicated by niche model). Thus, in the future, the municipalities harvesting H. speciosa will produce less because there will be less suitable habitat for H. speciosa, which in turn will affect the H. speciosa harvest and the local economy.

  15. Rapid diversification in Australia and two dispersals out of Australia in the globally distributed bee genus, Hylaeus (Colletidae: Hylaeinae).

    Science.gov (United States)

    Kayaalp, Pelin; Schwarz, Michael P; Stevens, Mark I

    2013-03-01

    Hylaeus is the only globally distributed colletid bee genus, with subgeneric and species-level diversity highest in Australia. We used one mitochondrial and two nuclear genes to reconstruct a phylogeny using Bayesian analyses of this genus based on species from Australia, Asia, Africa, Europe, Hawai'i, the New World and New Zealand. Our results concord with a ca. 30Mya Hylaeus crown age inferred by earlier studies, and we show that Hylaeus originated in Australia. Our phylogeny indicates only two dispersal events out of Australia, both shortly after the initial diversification of extant taxa. One of these dispersals was into New Zealand with only a minor subsequent radiation, but the second dispersal out of Australia resulted in a world-wide distribution. This second dispersal and radiation event, combined with very extensive early radiation of Hyleaus in Australia, poses a conundrum: what kinds of biogeographical and ecological factors could simultaneously drive global dispersal, yet strongly constrain further successful migrations out of Australia when geographical barriers appear to be weak? We argue that for hylaeine bees movement into new niches and enemy-free spaces may have favoured initial dispersal events, but that subsequent dispersals would not have entailed the original benefits of new niche space. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Building a Data Set over 12 Globally Distributed Sites to Support the Development of Agriculture Monitoring Applications with Sentinel-2

    Directory of Open Access Journals (Sweden)

    Sophie Bontemps

    2015-12-01

    Full Text Available Developing better agricultural monitoring capabilities based on Earth Observation data is critical for strengthening food production information and market transparency. The Sentinel-2 mission has the optimal capacity for regional to global agriculture monitoring in terms of resolution (10–20 meter, revisit frequency (five days and coverage (global. In this context, the European Space Agency launched in 2014 the “Sentinel­2 for Agriculture” project, which aims to prepare the exploitation of Sentinel-2 data for agriculture monitoring through the development of open source processing chains for relevant products. The project generated an unprecedented data set, made of “Sentinel-2 like” time series and in situ data acquired in 2013 over 12 globally distributed sites. Earth Observation time series were mostly built on the SPOT4 (Take 5 data set, which was specifically designed to simulate Sentinel-2. They also included Landsat 8 and RapidEye imagery as complementary data sources. Images were pre-processed to Level 2A and the quality of the resulting time series was assessed. In situ data about cropland, crop type and biophysical variables were shared by site managers, most of them belonging to the “Joint Experiment for Crop Assessment and Monitoring” network. This data set allowed testing and comparing across sites the methodologies that will be at the core of the future “Sentinel­2 for Agriculture” system.

  17. Global pharmacogenomics: distribution of CYP3A5 polymorphisms and phenotypes in the Brazilian population.

    Directory of Open Access Journals (Sweden)

    Guilherme Suarez-Kurtz

    Full Text Available The influence of self-reported "race/color", geographical origin and genetic ancestry on the distribution of three functional CYP3A5 polymorphisms, their imputed haplotypes and inferred phenotypes was examined in 909 healthy, adult Brazilians, self-identified as White, Brown or Black ("race/color" categories of the Brazilian census. The cohort was genotyped for CYP3A5*3 (rs776746, CYP3A5*6 (rs10264272 and CYP3A5*7 (rs41303343, CYP3A5 haplotypes were imputed and CYP3A5 metabolizer phenotypes were inferred according to the number of defective CYP3A5 alleles. Estimates of the individual proportions of Amerindian, African and European ancestry were available for the entire cohort. Multinomial log-linear regression models were applied to infer the statistical association between the distribution of CYP3A5 alleles, haplotypes and phenotypes (response variables, and self-reported Color, geographical region and ancestry (explanatory variables. We found that Color per se or in combination with geographical region associates significantly with the distribution of CYP3A5 variant alleles and CYP3A5 metabolizer phenotypes, whereas geographical region per se influences the frequency distribution of CYP3A5 variant alleles. The odds of having the default CYP3A5*3 allele and the poor metabolizer phenotype increases continuously with the increase of European ancestry and decrease of African ancestry. The opposite trend is observed in relation to CYP3A5*6, CYP3A5*7, the default CYP3A5*1 allele, and both the extensive and intermediate phenotypes. No significant effect of Amerindian ancestry on the distribution of CYP3A5 alleles or phenotypes was observed. In conclusion, this study strongly supports the notion that the intrinsic heterogeneity of the Brazilian population must be acknowledged in the design and interpretation of pharmacogenomic studies, and dealt with as a continuous variable, rather than proportioned in arbitrary categories that do not capture the

  18. A comparison of three-dimensional stress distribution and displacement of naso-maxillary complex on application of forces using quad-helix and nickel titanium palatal expander 2 (NPE2: a FEM study

    Directory of Open Access Journals (Sweden)

    Avinash Kumar

    2016-06-01

    Full Text Available Abstract Background Our objectives are to analyse and to compare the stress distribution and displacement of the craniofacial structures, following the application of forces from quad-helix and Nickel Titanium Palatal Expander-2 (NPE2 using finite element analysis. Methods Three-dimensional finite element models of young dried human skull, quad-helix appliance and NPE2 were constructed, and the initial activation of the expanders was stimulated to carry out the analysis and to evaluate the Von Misses stresses and displacement. Results Both the models demonstrated the highest stresses at the mid-palatal suture, with maximum posterior dislocation. The second highest stress was recorded at the fronto-zygomatic suture. The pattern of stress distribution was almost similar in both the groups, but NPE2 revealed lower magnitude stresses than quad-helix. The only exception being quad-helix model showed high stress levels around pterygo-maxillary suture whereas minimal stress around pterygo-maxillary suture was noticed after NPE2 activation. The cusp of the erupting canine and the erupting mesiobuccal cusp of the second molar showed outward, backward and downward displacement signifying increase in their eruption pattern following maxillary expansion. Conclusions Maxillary expansion using quad-helix and NPE2 can be used in posterior crossbite correction in cases where maximum skeletal changes are desirable at a younger age; it is furthermore effective in treating young patients with impacted or displaced teeth. Quad-helix and NPE2 produced acceptable forces for orthopaedic treatment even after being orthodontic appliances; their clinical application should be correctly planned as the effects of these appliances are largely age dependent.

  19. The global tropospheric ammonia distribution as seen in the 13-year AIRS measurement record

    Directory of Open Access Journals (Sweden)

    J. X. Warner

    2016-05-01

    Full Text Available Ammonia (NH3 plays an increasingly important role in the global biogeochemical cycle of reactive nitrogen as well as in aerosol formation and climate. We present extensive and nearly continuous global ammonia measurements made by the Atmospheric Infrared Sounder (AIRS from the Aqua satellite to identify and quantify major persistent and episodic sources as well as to characterize seasonality. We examine the 13-year period from September 2002 through August 2015 with a retrieval algorithm using an optimal estimation technique with a set of three, spatially and temporally uniform a priori profiles. Vertical profiles show good agreement (∼  5–15 % between AIRS NH3 and the in situ profiles from the winter 2013 DISCOVER-AQ (DISCOVER-Air Quality field campaign in central California, despite the likely biases due to spatial resolution differences between the two instruments. The AIRS instrument captures the strongest consistent NH3 concentrations due to emissions from the anthropogenic (agricultural source regions, such as South Asia (India/Pakistan, China, the United States (US, parts of Europe, Southeast (SE Asia (Thailand/Myanmar/Laos, the central portion of South America, as well as Western and Northern Africa. These correspond primarily to irrigated croplands, as well as regions with heavy precipitation, with extensive animal feeding operations and fertilizer applications where a summer maximum and a secondary spring maximum are reliably observable. In the Southern Hemisphere (SH regular agricultural fires contribute to a spring maximum. Regions of strong episodic emissions include Russia and Alaska as well as parts of South America, Africa, and Indonesia. Biomass burning, especially wildfires, dominate these episodic NH3 high concentrations.

  20. Towards a globally optimized crop distribution: Integrating water use, nutrition, and economic value

    Science.gov (United States)

    Davis, K. F.; Seveso, A.; Rulli, M. C.; D'Odorico, P.

    2016-12-01

    Human demand for crop production is expected to increase substantially in the coming decades as a result of population growth, richer diets and biofuel use. In order for food production to keep pace, unprecedented amounts of resources - water, fertilizers, energy - will be required. This has led to calls for `sustainable intensification' in which yields are increased on existing croplands while seeking to minimize impacts on water and other agricultural resources. Recent studies have quantified aspects of this, showing that there is a large potential to improve crop yields and increase harvest frequencies to better meet human demand. Though promising, both solutions would necessitate large additional inputs of water and fertilizer in order to be achieved under current technologies. However, the question of whether the current distribution of crops is, in fact, the best for realizing sustainable production has not been considered to date. To this end, we ask: Is it possible to increase crop production and economic value while minimizing water demand by simply growing crops where soil and climate conditions are best suited? Here we use maps of yields and evapotranspiration for 14 major food crops to identify differences between current crop distributions and where they can most suitably be planted. By redistributing crops across currently cultivated lands, we determine the potential improvements in calorie (+12%) and protein (+51%) production, economic output (+41%) and water demand (-5%). This approach can also incorporate the impact of future climate on cropland suitability, and as such, be used to provide optimized cropping patterns under climate change. Thus, our study provides a novel tool towards achieving sustainable intensification that can be used to recommend optimal crop distributions in the face of a changing climate while simultaneously accounting for food security, freshwater resources, and livelihoods.

  1. Distributional impacts of the 2008 global food price spike in Vietnam

    DEFF Research Database (Denmark)

    McKay, Andy; Tarp, Finn

    Agriculture and food cultivation production remains a key sector in the Vietnamese economy in terms of productive activities, income generation, and national export earnings. Higher world market prices should therefore in principle have a beneficial impact on rural farmers. This is based however...... the policy actions taken by the government to help reduce the impact on consumers, as well as to continue to encourage production. We also look at the distributional impact of the resulting domestic price changes, using data from a specialist rural household survey to look at production response. Vietnam...

  2. Distribution of N2O in the atmosphere under global warming - a simulation study with the MPI Earth System Model

    Science.gov (United States)

    Kracher, Daniela; Manzini, Elisa; Reick, Christian H.; Schultz, Martin; Stein, Olaf

    2014-05-01

    Climate change is driven by an increasing release of anthropogenic greenhouse gases (GHGs) such as carbon dioxide and nitrous oxide (N2O). Besides fossil fuel burning, also land use change and land management are anthropogenic sources of GHGs. Especially inputs of reactive nitrogen via fertilizer and deposition lead to enhanced emissions of N2O. One effect of a drastic future increase in surface temperature is a modification of atmospheric circulation, e.g. an accelerated Brewer Dobson circulation affecting the exchange between troposphere and stratosphere. N2O is inert in the troposphere and decayed only in the stratosphere. Thus, changes in atmospheric circulation, especially changes in the exchange between troposphere and stratosphere, will affect the atmospheric transport, decay, and distribution of N2O. In our study we assess the impact of global warming on atmospheric circulation and implied effects on the distribution and lifetime of atmospheric N2O. As terrestrial N2O emissions are highly determined by inputs of reactive nitrogen - the location of which being determined by human choice - we examine in particular the importance of latitudinal source regions of N2O for its global distribution. For this purpose we apply the Max Planck Institute Earth System Model, MPI-ESM. MPI-ESM consists of the atmospheric general circulation model ECHAM, the land surface model JSBACH, and MPIOM/HAMOCC representing ocean circulation and ocean biogeochemistry. Prognostic atmospheric N2O concentrations in MPI-ESM are determined by land N2O emissions, ocean N2O exchange and atmospheric tracer transport. As stratospheric chemistry is not explicitly represented in MPI-ESM, stratospheric decay rates of N2O are prescribed from a MACC MOZART simulation.

  3. Global Assimilation of EOS-Aura Data as a Means of Mapping Ozone Distribution in the Lower Stratosphere and Troposphere

    Science.gov (United States)

    Wargan, Krzysztof; Olsen, M.; Douglass, A.; Witte, J.; Strahan, S.; Livesey, N.

    2012-01-01

    Ozone in the lower stratosphere and the troposphere plays an important role in forcing the climate. However, the global ozone distribution in this region is not well known because of the sparse distribution of in-situ data and the poor sensitivity of satellite based observations to the lowermost of the atmosphere. The Ozone Monitoring Instrument (OMI) and Microwave Limb Sounder (MLS) instruments on EOS-Aura provide information on the total ozone column and the stratospheric ozone profile. This data has been assimilated into NASA s Global Earth Observing System, Version 5 (GEOS-5) data assimilation system (DAS). We will discuss the results of assimilating three years of OMI and MLS data into GEOS-5. This data was assimilated alongside meteorological observations from both conventional sources and satellite instruments. Previous studies have shown that combining observations from these instruments through the Trajectory Tropospheric Ozone Residual methodology (TTOR) or using data assimilation can yield useful, yet low biased, estimates of the tropospheric ozone budget. We show that the assimilated ozone fields in this updated version of GEOS-5 exhibit an excellent agreement with ozone sonde and High Resolution Dynamics Limb Sounder (HIRDLS) data in the lower stratosphere in terms of spatial and temporal variability as well as integrated ozone abundances. Good representation of small-scale vertical features follows from combining the MLS data with the assimilated meteorological fields. We then demonstrate how this information can be used to calculate the Stratosphere - Troposphere Exchange of ozone and its contribution to the tropospheric ozone column in GEOS-5. Evaluations of tropospheric ozone distributions from the assimilation will be made by comparisons with sonde and other in-situ observations.

  4. Genomic diversity of mumps virus and global distribution of the 12 genotypes.

    Science.gov (United States)

    Jin, Li; Örvell, Claes; Myers, Richard; Rota, Paul A; Nakayama, Tetsuo; Forcic, Dubravko; Hiebert, Joanne; Brown, Kevin E

    2015-03-01

    The WHO recently proposed an updated nomenclature for mumps virus (MuV). WHO currently recognizes 12 genotypes of MuV, assigned letters from A to N (excluding E and M), which are based on the nucleotide sequences of small hydrophobic (SH) and haemagglutinin-neuraminidase (HN) genes. A total of 66 MuV genomes are available in GenBank, representing eight of the 12 genotypes. To complete this dataset, whole genomes of seven isolates representing six genotypes (D, H, I, J, K and L) and one unclassified strain were sequenced. SH and HN genes of other representative strains were also sequenced. The degree of genetic divergence, predicted amino acid substitutions in the HN and fusion (F) proteins and geographic distributions of MuV strains were analysed based on the updated dataset. Nucleotide heterogeneity between genotypes reached 20% within the SH gene, with a maximum of 9% within the HN gene. The geographic and chronologic distributions of the 12 genotypes were summarised. This review contributes to our understanding of strain diversity for wild type MuV, and the results support the current WHO nomenclature. © 2014 Crown copyright. Reviews in Medical Virology © 2014 John Wiley & Sons, Ltd.

  5. Modeling and management of usage-aware distributed datasets for global Smart City Application Ecosystems

    Directory of Open Access Journals (Sweden)

    Johannes M. Schleicher

    2017-05-01

    Full Text Available The ever-growing amount of data produced by and in today’s smart cities offers significant potential for novel applications created by city stakeholders as well as third parties. Current smart city application models mostly assume that data is exclusively managed by and bound to its original application and location. We argue that smart city data must not be constrained to such data silos so that future smart city applications can seamlessly access and integrate data from multiple sources across multiple cities. In this paper, we present a methodology and toolset to model available smart city data sources and enable efficient, distributed data access in smart city environments. We introduce a modeling abstraction to describe the structure and relevant properties, such as security and compliance constraints, of smart city data sources along with independently accessible subsets in a technology-agnostic way. Based on this abstraction, we present a middleware toolset for efficient and seamless data access through autonomous relocation of relevant subsets of available data sources to improve Quality of Service for smart city applications based on a configurable mechanism. We evaluate our approach using a case study in the context of a distributed city infrastructure decision support system and show that selective relocation of data subsets can significantly reduce application response times.

  6. Cylindrospermopsis raciborskii: review of the distribution, phylogeography, and ecophysiology of a global invasive species

    Science.gov (United States)

    Antunes, Jorge T.; Leão, Pedro N.; Vasconcelos, Vítor M.

    2015-01-01

    Cylindrospermopsis raciborskii is a cyanobacterial species extensively studied for its toxicity, bloom formation and invasiveness potential, which have consequences to public and environmental health. Its current geographical distribution, spanning different climates, suggests that C. raciborskii has acquired the status of a cosmopolitan species. From phylogeography studies, a tropical origin for this species seems convincing, with different conjectural routes of expansion toward temperate climates. This expansion may be a result of the species physiological plasticity, or of the existence of different ecotypes with distinct environmental requirements. In particular, C. raciborskii is known to tolerate wide temperature and light regimes and presents diverse nutritional strategies. This cyanobacterium is also thought to have benefited from climate change conditions, regarding its invasiveness into temperate climates. Other factors, recently put forward, such as allelopathy, may also be important to its expansion. The effect of C. raciborskii in the invaded communities is still mostly unknown but may strongly disturb species diversity at different trophic levels. In this review we present an up-to-date account of the distribution, phylogeography, ecophysiology, as well some preliminary reports of the impact of C. raciborskii in different organisms. PMID:26042108

  7. Effects of the Wegener–Bergeron–Findeisen process on global black carbon distribution

    Directory of Open Access Journals (Sweden)

    L. Qi

    2017-06-01

    Full Text Available We systematically investigate the effects of Wegener–Bergeron–Findeisen process (hereafter WBF on black carbon (BC scavenging efficiency, surface BCair, deposition flux, concentration in snow (BCsnow, ng g−1, and washout ratio using a global 3-D chemical transport model (GEOS-Chem. We differentiate riming- versus WBF-dominated in-cloud scavenging based on liquid water content (LWC and temperature. Specifically, we implement an implied WBF parameterization using either temperature or ice mass fraction (IMF in mixed-phase clouds based on field measurements. We find that at Jungfraujoch, Switzerland, and Abisko, Sweden, where WBF dominates in-cloud scavenging, including the WBF effect strongly reduces the discrepancies of simulated BC scavenging efficiency and washout ratio against observations (from a factor of 3 to 10 % and from a factor of 4–5 to a factor of 2. However, at Zeppelin, Norway, where riming dominates, simulation of BC scavenging efficiency, BCair, and washout ratio become worse (relative to observations when WBF is included. There is thus an urgent need for extensive observations to distinguish and characterize riming- versus WBF-dominated aerosol scavenging in mixed-phase clouds and the associated BC scavenging efficiency. Our model results show that including the WBF effect lowers global BC scavenging efficiency, with a higher reduction at higher latitudes (8 % in the tropics and up to 76 % in the Arctic. The resulting annual mean BCair increases by up to 156 % at high altitudes and at northern high latitudes because of lower temperature and higher IMF. Overall, WBF halves the model–observation discrepancy (from −65 to −30 % of BCair across North America, Europe, China and the Arctic. Globally WBF increases BC burden from 0.22 to 0.29–0.35 mg m−2 yr−1, which partially explains the gap between observed and previous model-simulated BC burdens over land. In addition, WBF significantly increases

  8. Long Range Weather Prediction III: Miniaturized Distributed Sensors for Global Atmospheric Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Teller, E; Leith, C; Canavan, G; Wood, L

    2001-11-13

    We continue consideration of ways-and-means for creating, in an evolutionary, ever-more-powerful manner, a continually-updated data-base of salient atmospheric properties sufficient for finite differenced integration-based, high-fidelity weather prediction over intervals of 2-3 weeks, leveraging the 10{sup 14} FLOPS digital computing systems now coming into existence. A constellation comprised of 10{sup 6}-10{sup 9} small atmospheric sampling systems--high-tech superpressure balloons carrying early 21st century semiconductor devices, drifting with the local winds over the meteorological spectrum of pressure-altitudes--that assays all portions of the troposphere and lower stratosphere remains the central feature of the proposed system. We suggest that these devices should be active-signaling, rather than passive-transponding, as we had previously proposed only for the ground- and aquatic-situated sensors of this system. Instead of periodic interrogation of the intra-atmospheric transponder population by a constellation of sophisticated small satellites in low Earth orbit, we now propose to retrieve information from the instrumented balloon constellation by existing satellite telephony systems, acting as cellular tower-nodes in a global cellular telephony system whose ''user-set'' is the atmospheric-sampling and surface-level monitoring constellations. We thereby leverage the huge investment in cellular (satellite) telephony and GPS technologies, with large technical and economic gains. This proposal minimizes sponsor forward commitment along its entire programmatic trajectory, and moreover may return data of weather-predictive value soon after field activities commence. We emphasize its high near-term value for making better mesoscale, relatively short-term weather predictions with computing-intensive means, and its great long-term utility in enhancing the meteorological basis for global change predictive studies. We again note that adverse

  9. Review of the Global Distribution of Foot-and-Mouth Disease Virus from 2007 to 2014.

    Science.gov (United States)

    Brito, B P; Rodriguez, L L; Hammond, J M; Pinto, J; Perez, A M

    2017-04-01

    Foot-and-mouth disease (FMD) virus affects livestock worldwide. There are seven different serotypes, each with a diversity of topotypes, genetic lineages and strains. Some lineages have different properties that may contribute to sporadic spread beyond their recognized endemic areas. The objective of this study was to review the most significant FMD epidemiological events that took place worldwide between 2007 and 2014. Severe epidemics were caused by FMD virus (FMDV) lineage O/Asia/Mya-98 in Japan and South Korea in 2010, both previously free of disease. In India, where FMD is endemic, the most important event was the re-emergence of lineage O/ME-SA/Ind-2001 in 2008. Notably, this lineage, normally restricted to India, Bangladesh, Nepal and Bhutan, was also found in Saudi Arabia and Libya in 2013 and has caused several outbreaks in Tunisia and Algeria in 2014-2015. In January 2011, FMDV-positive wild boars were found in Bulgaria, where the disease last occurred in 1996, followed by 12 outbreaks in livestock infected with FMDV O/ME-SA/PanAsia2. In 2012, FMDV SAT2 caused outbreaks in Egypt and the Palestinian Autonomous Territories. Another significant event was the emergence of FMDV Asia1 Sindh-08 in the Middle East. In South America, one outbreak of FMDV serotype O, topotype Euro-SA was reported in Paraguay in 2011, which was recognized as FMD-free with vaccination at the time. Lessons learned from past events, point out the need for an integrated strategy that comprises coordinated global and regional efforts for FMDV control and surveillance. Specific local characteristics related to host, environment and virus that condition FMD occurrence should be carefully considered and incorporated to adapt appropriate strategies into local plans. In this review, we compiled relevant epidemiological FMD events to provide a global overview of the current situation. We further discussed current challenges present in different FMD areas. Published (2015). This article is a U

  10. Global distribution and climate forcing of marine organic aerosol: 1. Model improvements and evaluation

    Science.gov (United States)

    Meskhidze, N.; Xu, J.; Gantt, B.; Zhang, Y.; Nenes, A.; Ghan, S. J.; Liu, X.; Easter, R.; Zaveri, R.

    2011-11-01

    Marine organic aerosol emissions have been implemented and evaluated within the National Center of Atmospheric Research (NCAR)'s Community Atmosphere Model (CAM5) with the Pacific Northwest National Laboratory's 7-mode Modal Aerosol Module (MAM-7). Emissions of marine primary organic aerosols (POA), phytoplankton-produced isoprene- and monoterpenes-derived secondary organic aerosols (SOA) and methane sulfonate (MS-) are shown to affect surface concentrations of organic aerosols in remote marine regions. Global emissions of submicron marine POA is estimated to be 7.9 and 9.4 Tg yr-1, for the Gantt et al. (2011) and Vignati et al. (2010) emission parameterizations, respectively. Marine sources of SOA and particulate MS- (containing both sulfur and carbon atoms) contribute an additional 0.2 and 5.1 Tg yr-1, respectively. Widespread areas over productive waters of the Northern Atlantic, Northern Pacific, and the Southern Ocean show marine-source submicron organic aerosol surface concentrations of 100 ng m-3, with values up to 400 ng m-3 over biologically productive areas. Comparison of long-term surface observations of water insoluble organic matter (WIOM) with POA concentrations from the two emission parameterizations shows that despite revealed discrepancies (often more than a factor of 2), both Gantt et al. (2011) and Vignati et al. (2010) formulations are able to capture the magnitude of marine organic aerosol concentrations, with the Gantt et al. (2011) parameterization attaining better seasonality. Model simulations show that the mixing state of the marine POA can impact the surface number concentration of cloud condensation nuclei (CCN). The largest increases (up to 20%) in CCN (at a supersaturation (S) of 0.2%) number concentration are obtained over biologically productive ocean waters when marine organic aerosol is assumed to be externally mixed with sea-salt. Assuming marine organics are internally-mixed with sea-salt provides diverse results with increases

  11. Global distribution and climate forcing of marine organic aerosol - Part 1: Model improvements and evaluation

    Science.gov (United States)

    Meskhidze, N.; Xu, J.; Gantt, B.; Zhang, Y.; Nenes, A.; Ghan, S. J.; Liu, X.; Easter, R.; Zaveri, R.

    2011-07-01

    Marine organic aerosol emissions have been implemented and evaluated within the National Center of Atmospheric Research (NCAR)'s Community Atmosphere Model (CAM5) with the Pacific Northwest National Laboratory's 7-mode Modal Aerosol Module (MAM-7). Emissions of marine primary organic aerosols (POA), phytoplankton-produced isoprene- and monoterpenes-derived secondary organic aerosols (SOA) and methane sulfonate (MS-) are shown to affect surface concentrations of organic aerosols in remote marine regions. Global emissions of submicron marine POA is estimated to be 7.9 and 9.4 Tg yr-1, for the Gantt et al. (2011) and Vignati et al. (2010) emission parameterizations, respectively. Marine sources of SOA and particulate MS- (containing both sulfur and carbon atoms) contribute an additional 0.2 and 5.1 Tg yr-1, respectively. Widespread areas over productive waters of the Northern Atlantic, Northern Pacific, and the Southern Ocean show marine-source submicron organic aerosol surface concentrations of 100 ng m-3, with values up to 400 ng m-3 over biologically productive areas. Comparison of long-term surface observations of water insoluble organic matter (WIOM) with POA concentrations from the two emission parameterizations shows that both Gantt et al. (2011) and Vignati et al. (2010) formulations are able to capture the magnitude of marine organic aerosol concentrations, with the Gantt et al. (2011) parameterization attaining better seasonality. Model simulations show that the mixing state of the marine POA can impact the surface number concentration of cloud condensation nuclei (CCN). The largest increases (up to 20 %) in CCN (at a supersaturation (S) of 0.2 %) number concentration are obtained over biologically productive ocean waters when marine organic aerosol is assumed to be externally mixed with sea-salt. Assuming marine organics are internally-mixed with sea-salt provides diverse results with increase and decrease in the concentration of CCN over different parts of

  12. Ectomycorrhizal lifestyle in fungi: global diversity, distribution, and evolution of phylogenetic lineages.

    Science.gov (United States)

    Tedersoo, Leho; May, Tom W; Smith, Matthew E

    2010-04-01

    The ectomycorrhizal (EcM) symbiosis involves a large number of plant and fungal taxa worldwide. During studies on EcM diversity, numerous misidentifications, and contradictory reports on EcM status have been published. This review aims to: (1) critically assess the current knowledge of the fungi involved in the EcM by integrating data from axenic synthesis trials, anatomical, molecular, and isotope studies; (2) group these taxa into monophyletic lineages based on molecular sequence data and published phylogenies; (3) investigate the trophic status of sister taxa to EcM lineages; (4) highlight other potentially EcM taxa that lack both information on EcM status and DNA sequence data; (5) recover the main distribution patterns of the EcM fungal lineages in the world. Based on critically examining original reports, EcM lifestyle is proven in 162 fungal genera that are supplemented by two genera based on isotopic evidence and 52 genera based on phylogenetic data. Additionally, 33 genera are highlighted as potentially EcM based on habitat, although their EcM records and DNA sequence data are lacking. Molecular phylogenetic and identification studies suggest that EcM symbiosis has arisen independently and persisted at least 66 times in fungi, in the Basidiomycota, Ascomycota, and Zygomycota. The orders Pezizales, Agaricales, Helotiales, Boletales, and Cantharellales include the largest number of EcM fungal lineages. Regular updates of the EcM lineages and genera therein can be found at the UNITE homepage http://unite.ut.ee/EcM_lineages . The vast majority of EcM fungi evolved from humus and wood saprotrophic ancestors without any obvious reversals. Herbarium records from 11 major biogeographic regions revealed three main patterns in distribution of EcM lineages: (1) Austral; (2) Panglobal; (3) Holarctic (with or without some reports from the Austral or tropical realms). The holarctic regions host the largest number of EcM lineages; none are restricted to a tropical

  13. Development of microsatellite markers for globally distributed populations of the threatened silky shark, Carcharhinus falciformis

    KAUST Repository

    O’Bryhim, J. R.

    2014-12-05

    Eighteen microsatellite loci were developed for the silky shark Carcharhinus falciformis and screened across a total of 53 individuals from the western Atlantic Ocean, Eastern Tropical Pacific Ocean, and Red Sea. The number of alleles per locus ranged from 3 to 19, observed heterozygosity ranged from 0.158 to 0.917, and the probability of identity values ranged from 0.010 to 0.460. Though believed to be one of the most abundant species of large sharks, C. falciformis were recently listed as “near threatened” globally and “vulnerable” in the Eastern Tropical Pacific by the IUCN, due to reductions in catch rates from both target and non-target fisheries (Dulvy et al. in Aquat Conserv 18:459–482, 2008). Very little information exists about the population structure and genetic diversity of C. falciformis around the world. These new loci will provide effective tools for examining the sustainability of this declining species. © 2014, Springer Science+Business Media Dordrecht.

  14. Distributions of positive correlations in sectoral value added growth in the global economic network*

    Science.gov (United States)

    Maluck, Julian; Donner, Reik V.

    2017-02-01

    International trade has grown considerably during the process of globalization. Complex supply chains for the production of goods have resulted in an increasingly connected International Trade Network (ITN). Traditionally, direct trade relations between industries have been regarded as mediators of supply and demand spillovers. With increasing network connectivity the question arises if higher-order relations become more important in explaining a national sector's susceptibility to supply and demand changes of its trading partner. In this study we address this question by investigating empirically to what extent the topological properties of the ITN provide information about positive correlations in the production of two industry sectors. We observe that although direct trade relations between industries serve as important indicators for correlations in the industries' value added growth, opportunities of substitution for required production inputs as well as second-order trade relations cannot be neglected. Our results contribute to a better understanding of the relation between trade and economic productivity and can serve as a basis for the improvement of crisis spreading models that evaluate contagion threats in the case of a node's failure in the ITN.

  15. Successfully Changing the Landscape of Information Distribution: Extension Food Website Reaches People Locally and Globally

    Directory of Open Access Journals (Sweden)

    Alice Henneman

    2016-02-01

    Full Text Available The goal of the Food website was to develop Internet-based content that was relevant and reached the general public and multiplier groups, such as educators, health professionals, and media outlets. The purpose of this paper was to examine whether a multi-modal approach to information delivery through increases in and changes to content, electronic mailing list creation, and social media posting impacted user access, traffic channels, and referrals from 2010 to 2014. When comparing 2010-2011 versus 2013-2014, there was a 150% increase in total pageviews, 197% increase in unique pageviews, and a 39% increase in average time spent on a page. Since 2010, the website had over 5.2 million total pageviews, 3.1 million sessions, and 2.6 million users. In 2014, top social media referrals included Pinterest, Facebook, LinkedIn, and Twitter. Age of visitors ranged from 18 to 65+, with 45% being 18-34 years old. Approximately 70% were female. Visitors came from 229 countries/territories and 18,237 different cities. The website connects Nebraska and the world to the exciting food research and information generated at the University of Nebraska-Lincoln and is playing an increasingly important role in shaping the future of food in the local and global community.

  16. The global distribution of Earth's critical zone and its controlling factors

    Science.gov (United States)

    Xu, Xianli; Liu, Wen

    2017-04-01

    The near-surface layer of Earth which provides essential elements for supporting life is now recognized as the critical zone (CZ). This study provides the first global assessment of the CZ thickness (CZT) and its controlling factors by combining data sets of climate, vegetation height (VH), water table depth (WTD), groundwater thickness (GWT), topography, and lithologic data. The analysis shows that CZT ranges from 0.7 to 223.5 m with an average value of 36.8 m across continental areas; CZT is thickest in midlatitudes (subtropical to temperate zones). The proportion of aboveground part (VH) to CZT is 19.9 ± 16.7% (mean ±one standard deviation), while it is 80.1 ± 16.7% for the underground part (WTD + GWT). A generalized linear model shows that compound topographic index (ln(a/tan(b)), where a is the upslope contributing area and b is the slope degree of the landscape) and potential evapotranspiration are the first two major controlling factors on the variations in CZT. This study opens opportunities for further advancing CZ science by providing one of its most important properties—its thickness.

  17. Genotypic distribution of single nucleotide polymorphisms in oral cancer: global scene.

    Science.gov (United States)

    Multani, Shaleen; Saranath, Dhananjaya

    2016-11-01

    Globocan 2012 reports the global oral cancer incidence of 300,373 new oral cancer cases annually, contributing to 2.1 % of the world cancer burden. The major well-established risk factors for oral cancer include tobacco, betel/areca nut, alcohol and high-risk oncogenic human papilloma virus (HPV) 16/18. However, only 5-10 % of individuals with high-risk lifestyle develop oral cancer. Thus, genomic variants in individuals represented as single nucleotide polymorphisms (SNPs) influence susceptibility to oral cancer. With a view to understanding the role of genomic variants in oral cancer, we reviewed SNPs in case-control studies with a minimum of 100 cases and 100 controls. PubMed and HuGE navigator search engines were used to obtain data published from 1990 to 2015, which identified 67 articles investigating the role of SNPs in oral cancer. Single publications reported 93 SNPs in 55 genes, with 34 SNPs associated with a risk of oral cancer. Meta-analysis of data in multiple studies defined nine SNPs associated with a risk of oral cancer. The genes were associated with critical functions deregulated in cancers, including cell proliferation, immune function, inflammation, transcription, DNA repair and xenobiotic metabolism.

  18. The global distribution of the dusk-to-nighttime enhancement of summer NmF2 at solar minimum

    Science.gov (United States)

    Chen, Yiding; Liu, Libo; Le, Huijun; Wan, Weixing; Zhang, Hui

    2016-08-01

    In this paper, the dusk-to-nighttime enhancement (DNE) of summer NmF2 was investigated based on Constellation Observing System for Meteorology, Ionosphere, and Climate radio occultation observations at solar minimum. The global distributions of the magnitude and the peak time of the DNE as well as the role of the DNE in NmF2 diurnal cycle were presented. The DNE mainly exists in three regions (one in the Southern Hemisphere and two in the Northern Hemisphere), and its distribution is related to geomagnetic configuration, especially in the Southern Hemisphere. For most DNEs, their peaks correspond to the maxima of NmF2 diurnal cycle. The DNEs are much more prominent in the southern than in the northern summer hemisphere; they last to later nighttime hours, have larger magnitudes, and play more important roles in NmF2 diurnal cycle in the southern than in the northern summer hemisphere. The distribution of the DNE was analyzed in terms of photoionization and the vertical plasma drift induced by neutral winds. The positive geomagnetic declinations and the smaller geomagnetic inclinations at higher geographic latitudes over the South Pacific are crucial for the prominent DNEs in the southern summer hemisphere; they result in larger upward plasma drift at higher latitudes where photoionization is still significant at sunset and evening hours.

  19. The potential effect of global warming on the geographic and seasonal distribution of Phlebotomus papatasi in Southwest Asia

    Energy Technology Data Exchange (ETDEWEB)

    Cross, E.R.; Hyams, K.C. [Naval Medical Research Inst., Bethesda, MD (United States)

    1996-07-01

    The distribution of Phlebotomus papatasi in Southwest Asia is thought to be highly dependent on temperature and relative humidity. A discriminant analysis model based on weather data and reported vector surveys was developed to predict the seasonal and geographic distribution of P. papatasi in this region. To simulate global warming, temperature values for 115 weather stations were increased by 1 {degrees}C, 3{degrees}C, and 5{degrees}C, and the outcome variable coded as unknown in the model. Probability of occurrence values were then predicted for each location with a weather station. Stations with positive probability of occurrence values for May, June, July, and August were considered locations where two or more life cycles of P. papatasi could occur and which could support endemic transmission of leishmaniasis and sandfly fever. Among 115 weather stations, 71 (62%) would be considered endemic with current temperature conditions; 14 (12%) additional station could become endemic with an increase of 1 {degrees}C; 17 (15%) more than a 3{degrees}C increase; and 12 (10%) more (all but one station) with a t{degrees}C increase. In addition to increased geographic distribution, seasonality of disease transmission could be extended throughout 12 months of the year in 7 (6%) locations with at least a 3{degrees}C rise in temperature and in 29 (25%) locations with a 5{degrees}C rise. 15 refs., 4 figs.

  20. Small- and large-x nucleon spin structure from a global QCD analysis of polarized parton distribution functions

    Directory of Open Access Journals (Sweden)

    E.R. Nocera

    2015-03-01

    Full Text Available I investigate the behavior of spin-dependent parton distribution functions in the regions of small and large momentum fractions x. I present a systematic comparison between predictions for relevant observables obtained with various models of nucleon spin structure and a recent global analysis of spin-dependent distributions, NNPDFpol1.1. Together with its unpolarized counterpart, NNPDF2.3, they form a mutually consistent set of parton distributions. Because they include most of the available experimental information, and are determined with a minimally biased methodology, these are especially suited for such a study. I show how NNPDFpol1.1 can discriminate between different theoretical models, even though NNPDF uncertainties remain large near the endpoints x→0 and x→1, due to the lack of experimental information. I discuss how our knowledge of nucleon spin structure may be improved at small x by future measurements at an Electron–Ion Collider, and at large x by recent measurements at Jefferson Lab, also in view of its 12 GeV upgrade.

  1. Potential Distribution of Podocnemis lewyana (Reptilia:Podocnemididae and Its Possible Fluctuation Under Different Global Climate Change Scenarios

    Directory of Open Access Journals (Sweden)

    Carlos Ortiz-Yusty

    2014-06-01

    Full Text Available We implemented a species distribution modelling approach to establish the potential distribution of Podocnemis lewyana, to explore the climatic factors that may influence the species’ distribution and to evaluate possible changes in distribution under future climate scenarios. The distribution models predicted a continuous distribution from south to north along the Magdalena River, from Rivera and Palermo in the department of Huila to the departments of Atlántico and Magdalena in the north. Temperature was the variable most influential in the distribution of P. lewyana; this species tends to be present in warm regions with low temperature variability. The distribution model predicted an increase in the geographic range of P. lewyana under climate change scenarios. However, taking into account the habitat preferences of this species and its strong association with water, this result should be treated with caution since the model considered only terrestrial climatic variables. Given the life history characteristics of this species (temperature-dependent sex determination, high pivotal temperature and a very narrow transition range and the negative effect of changes in hydrological regimes on embryo survival, expansion of the potential distribution of P. lewyana in the future does not mean that the species will not be affected by global climate change.DISTRIBUCIÓN POTENCIAL DE (Podocnemis lewyana, REPTILIA: Podocnemididae Y SU POSIBLE FLUCTUACIÓN BAJO ESCENARIOS DE CAMBIO CLIMÁTICO GLOBALEn este estudio se implementó el modelaje de distribución de especies para establecer el rango de distribución potencial de Podocnemis lewyana, explorar los componentes del clima que pueden influenciar dicha distribución y evaluar posibles fluctuaciones de su distribución bajo escenarios de clima futuro. Los modelos obtenidos predicen una distribución continua de sur a norte por todo el río Magdalena, desde los municipios de Rivera y Palermo en el

  2. Layouts of Expander Graphs

    OpenAIRE

    Dujmović, Vida; Sidiropoulos, Anastasios; Wood, David R.

    2015-01-01

    Bourgain and Yehudayoff recently constructed $O(1)$-monotone bipartite expanders. By combining this result with a generalisation of the unraveling method of Kannan, we construct 3-monotone bipartite expanders, which is best possible. We then show that the same graphs admit 3-page book embeddings, 2-queue layouts, 4-track layouts, and have simple thickness 2. All these results are best possible.

  3. Deriving global Olivine distribution on Hayabusa's target (25143) Itokawa using Near-Infrared Spectrometer data

    Science.gov (United States)

    Nardi, L.; Palomba, E.; Longobardo, A.; Galiano, A.; Dirri, F.

    2017-09-01

    In 2005 Hayabusa spacecraft visited asteroid Itokawa, bringing back surface samples to Earth in 2010. Near-Infrared data taken by NIRS and samples analysis confirmed hypothesis made through ground-based observations, in particular the one that sees Itokawa as an LL-chondrite like asteroid processed by space weathering. In this work, we apply spectral indices for olivine detection. In particular, we define the BAR* and relate it to the olivine abundance, by means of calibration on laboratory data. We present the distribution of BAR* calculated for nearly 38.000 spectra taken from an altitude of 3.5-7 km, defined as Home Position, which was the longest mission observation phase. In addition, a plot of olivine normalized content versus BAR* for RELAB compounds is given.

  4. On Dark Energy and Matter of the Expanding Universe

    Directory of Open Access Journals (Sweden)

    Lehnert B.

    2009-04-01

    Full Text Available At present the expanding universe is observed to be dominated by the not fully under- stood concepts of dark energy and matter, in a conceived almost flat Euclidian geometry. As one of the possible efforts to understand the global behaviour of the expanding uni- verse, the present paper attempts to explain these concepts in terms of the pressure force and gravity of a spherical photon gas cloud of zero point energy, in a flat geometry. A difficult point of the conventional theory concerns the frequency distribution of the zero point energy oscillations which leads to the unacceptable result of an infinite total en- ergy per unit volume. A modification of this distribution is therefore proposed which results in finite energy density. A corresponding equilibrium state is investigated, as well as small dynamic deviations from it, to form a basis for a model of the expanding universe. Provided that the crucial points of the present approach hold true, the model satisfies the requirements of cosmic linear dimensions, results in an estimated accelera- tion of the expansion being of the order of the observed one, presents a possible solution of the coincidence problem of dark energy and matter, and provides one of the possible explanations of the observed excess of high-energy electrons and positrons in recent balloon and satellite experiments.

  5. Efficient optimization of lithographic process conditions using a distributed, combined global/local search approach

    Science.gov (United States)

    Fühner, Tim; Popp, Stephan; Dürr, Christoph; Erdmann, Andreas

    2006-03-01

    This paper presents improvements and extensions that have been applied to our earlier presented approach of mutually optimizing lithographic illumination and mask settings. Our work aims at two aspects: (1) improvements of the optimization approach and (2) of the simulation scheme used for the optimization. As described earlier, the main problem of the proposed optimization approach is the high requirement of computation time. One solution is to extensively distribute calculations onto different computers. As an alternative to the former approach using MPI, a new improved technique is proposed, which makes use of the Python powered framework Twisted. This allows for a fail-safe and load-balanced distribution of calculations in a heterogeneous network environment. Another enhancement is the integration of local optimization routines into the proposed concept. For that, the state-of-the-art optimization toolkit of Matlab has been integrated into our approach. By combining our genetic algorithm with local search methods it is not only possible to increase the overall optimization performance, but also to evaluate local environments in the search space, which helps to assess the technical stability of solutions. As a first example the non-linear SQP (sequential quadratic programming) has been used, allowing for constrained problem specifications. Furthermore, the simulation itself was drastically improved in terms of efficiency. For example, instead of evaluating all solutions at the same numerical resolution, as a first step, a coarse-grained evaluation is performed, only if a solution's merit lies above a certain threshold, a detailed analysis at a higher (numerical) resolution is conducted. Various tests demonstrate not only the increase in efficiency obtained with the newly incorporated measures, but also show new results for a combined optimization of different mask features.

  6. Global distribution and origin of target site insecticide resistance mutations in Tetranychus urticae.

    Science.gov (United States)

    Ilias, A; Vontas, J; Tsagkarakou, A

    2014-05-01

    The control of Tetranychus urticae, a worldwide agricultural pest, is largely dependent on pesticides. However, their efficacy is often compromised by the development of resistance. Recent molecular studies identified a number of target site resistance mutations, such as G119S, A201S, T280A, G328A, F331W in the acetylcholinesterase gene, L1024V, A1215D, F1538I in the voltage-gated sodium channel gene, G314D and G326E in glutamate-gated chloride channel genes, G126S, I136T, S141F, D161G, P262T in the cytochrome b and the I1017F in the chitin synthase 1 gene. We examined their distribution, by sequencing the relevant gene fragments in a large number of T. urticae collections from a wide geographic range. Our study revealed that most of the resistance mutations are spread worldwide, with remarkably variable frequencies. Furthermore, we analyzed the variability of the ace locus, which has been subjected to longer periods of selection pressure historically, to investigate the evolutionary origin of ace resistant alleles and determine whether they resulted from single or multiple mutation events. By sequencing a 1540 bp ace fragment, encompassing the resistance mutations and downstream introns in 139 T. urticae individuals from 27 countries, we identified 6 susceptible and 31 resistant alleles which have arisen from at least three independent mutation events. The frequency and distribution of these ace haplotypes varied geographically, suggesting an interplay between different mutational events, gene flow and local selection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Transoceanic dispersal and plate tectonics shaped global cockroach distributions: evidence from mitochondrial phylogenomics.

    Science.gov (United States)

    Bourguignon, Thomas; Qian, Tang; Ho, Simon Y W; Juna, Frantisek; Wang, Zongqing; Arab, Daej A; Cameron, Stephen L; Walker, James; Rentz, David; Evans, Theodore A; Lo, Nathan

    2018-02-06

    Following the acceptance of plate tectonics theory in the latter half of the 20th century, vicariance became the dominant explanation for the distributions of many plant and animal groups. In recent years, however, molecular-clock analyses have challenged a number of well-accepted hypotheses of vicariance. As a widespread group of insects with a fossil record dating back 300 million years, cockroaches provide an ideal model for testing hypotheses of vicariance through plate tectonics vs transoceanic dispersal. However, their evolutionary history remains poorly understood, in part due to unresolved relationships among the nine recognized families. Here we present a phylogenetic estimate of all extant cockroach families, as well as a timescale for their evolution, based on the complete mitochondrial genomes of 119 cockroach species. Divergence dating analyses indicated that the last common ancestor of all extant cockroaches appeared ∼235 million years ago, approximately 95 million years prior to the appearance of fossils that can be assigned to extant families, and before the breakup of Pangaea began. We reconstructed the geographic ranges of ancestral cockroaches and found tentative support for vicariance through plate tectonics within and between several major lineages. We also found evidence of transoceanic dispersal in lineages found across the Australian, Indo-Malayan, African, and Madagascan regions. Our analyses provide evidence that both vicariance and dispersal have played important roles in shaping the distribution and diversity of these insects. © The Author 2018. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Global Monitoring of Salmonella Serovar Distribution from the World Health Organization Global Foodborne Infections Network Country Data Bank: Results of Quality Assured Laboratories from 2001 to 2007

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Vieira, Antonio; Karlsmose, Susanne

    2011-01-01

    most frequently identified serovars of Salmonella isolated from humans from 2001 to 2007 in laboratories from 37 countries that participated in World Health Organization Global Foodborne Infections Network and demonstrated serotyping proficiency in the Global Foodborne Infections Network External...

  9. Advances in global sensitivity analyses of demographic-based species distribution models to address uncertainties in dynamic landscapes

    Directory of Open Access Journals (Sweden)

    Ilona Naujokaitis-Lewis

    2016-07-01

    Full Text Available Developing a rigorous understanding of multiple global threats to species persistence requires the use of integrated modeling methods that capture processes which influence species distributions. Species distribution models (SDMs coupled with population dynamics models can incorporate relationships between changing environments and demographics and are increasingly used to quantify relative extinction risks associated with climate and land-use changes. Despite their appeal, uncertainties associated with complex models can undermine their usefulness for advancing predictive ecology and informing conservation management decisions. We developed a computationally-efficient and freely available tool (GRIP 2.0 that implements and automates a global sensitivity analysis of coupled SDM-population dynamics models for comparing the relative influence of demographic parameters and habitat attributes on predicted extinction risk. Advances over previous global sensitivity analyses include the ability to vary habitat suitability across gradients, as well as habitat amount and configuration of spatially-explicit suitability maps of real and simulated landscapes. Using GRIP 2.0, we carried out a multi-model global sensitivity analysis of a coupled SDM-population dynamics model of whitebark pine (Pinus albicaulis in Mount Rainier National Park as a case study and quantified the relative influence of input parameters and their interactions on model predictions. Our results differed from the one-at-time analyses used in the original study, and we found that the most influential parameters included the total amount of suitable habitat within the landscape, survival rates, and effects of a prevalent disease, white pine blister rust. Strong interactions between habitat amount and survival rates of older trees suggests the importance of habitat in mediating the negative influences of white pine blister rust. Our results underscore the importance of considering habitat

  10. Global distribution and climate forcing of marine organic aerosol: 1. Model improvements and evaluation

    Directory of Open Access Journals (Sweden)

    N. Meskhidze

    2011-11-01

    Full Text Available Marine organic aerosol emissions have been implemented and evaluated within the National Center of Atmospheric Research (NCAR's Community Atmosphere Model (CAM5 with the Pacific Northwest National Laboratory's 7-mode Modal Aerosol Module (MAM-7. Emissions of marine primary organic aerosols (POA, phytoplankton-produced isoprene- and monoterpenes-derived secondary organic aerosols (SOA and methane sulfonate (MS are shown to affect surface concentrations of organic aerosols in remote marine regions. Global emissions of submicron marine POA is estimated to be 7.9 and 9.4 Tg yr−1, for the Gantt et al. (2011 and Vignati et al. (2010 emission parameterizations, respectively. Marine sources of SOA and particulate MS (containing both sulfur and carbon atoms contribute an additional 0.2 and 5.1 Tg yr−1, respectively. Widespread areas over productive waters of the Northern Atlantic, Northern Pacific, and the Southern Ocean show marine-source submicron organic aerosol surface concentrations of 100 ng m−3, with values up to 400 ng m−3 over biologically productive areas. Comparison of long-term surface observations of water insoluble organic matter (WIOM with POA concentrations from the two emission parameterizations shows that despite revealed discrepancies (often more than a factor of 2, both Gantt et al. (2011 and Vignati et al. (2010 formulations are able to capture the magnitude of marine organic aerosol concentrations, with the Gantt et al. (2011 parameterization attaining better seasonality. Model simulations show that the mixing state of the marine POA can impact the surface number concentration of cloud condensation nuclei (CCN. The largest increases (up to 20% in CCN (at a supersaturation (S of 0.2% number concentration are obtained over biologically productive ocean waters when marine organic aerosol is assumed to be externally mixed with sea-salt. Assuming

  11. Is the distribution of Prochlorococcus and Synechococcus ecotypes in the Mediterranean Sea affected by global warming?

    Directory of Open Access Journals (Sweden)

    M. Ostrowski

    2011-09-01

    Full Text Available Biological communities populating the Mediterranean Sea, which is situated at the northern boundary of the subtropics, are often claimed to be particularly affected by global warming. This is indicated, for instance, by the introduction of (subtropical species of fish or invertebrates that can displace local species. This raises the question of whether microbial communities are similarly affected, especially in the Levantine basin where sea surface temperatures have significantly risen over the last 25 years (0.50 ± 0.11 °C in average per decade, P Prochlorococcus and Synechococcus, was examined during two cruises through both eastern and western Mediterranean Sea basins held in September 1999 (PROSOPE cruise and in June–July 2008 (BOUM cruise. Diversity was studied using dot blot hybridization with clade-specific 16S rRNA oligonucleotide probes and/or clone libraries of the 16S-23S ribosomal DNA Internal Transcribed Spacer (ITS region, with a focus on the abundance of clades that may constitute bioindicators of warm waters. During both cruises, the dominant Prochlorococcus clade in the upper mixed layer at all stations was HLI, a clade typical of temperate waters, whereas the HLII clade, the dominant group in (subtropical waters, was only present at very low concentrations. The Synechococcus community was dominated by clades I, III and IV in the northwestern waters of the Gulf of Lions and by clade III and groups genetically related to clades WPC1 and VI in the rest of the Mediterranean Sea. In contrast, only a few sequences of clade II, a group typical of warm waters, were observed. These data indicate that local cyanobacterial populations have not yet been displaced by their (subtropical counterparts.

  12. Top-down control of soil fungal community composition by a globally distributed keystone consumer.

    Science.gov (United States)

    Crowther, Thomas W; Stanton, David W G; Thomas, Stephen M; A'Bear, A Donald; Hiscox, Jennifer; Jones, T Hefin; Vorísková, Jana; Baldrian, Petr; Boddy, Lynne

    2013-11-01

    The relative contribution of top-down and bottom-up processes regulating primary decomposers can influence the strength of the link between the soil animal community and ecosystem functioning. Although soil bacterial communities are regulated by bottom-up and top-down processes, the latter are considered to be less important in structuring the diversity and functioning of fungal-dominated ecosystems. Despite the huge diversity of mycophagous (fungal-feeding) soil fauna, and their potential to reverse the outcomes of competitive fungal interactions, top-down grazing effects have never been found to translate to community-level changes. We constructed soil mesocosms to investigate the potential of isopods grazing on cord-forming basidiomycete fungi to influence the community composition and functioning of a complex woodland soil microbial community. Using metagenomic sequencing we provide conclusive evidence of direct top-down control at the community scale in fungal-dominated woodland soil. By suppressing the dominant cord-forming basidiomycete fungi, isopods prevented the competitive exclusion of surrounding litter fungi, increasing diversity in a community containing several hundred fungal species. This isopod-induced modification of community composition drove a shift in the soil enzyme profile, and led to a restructuring of the wider mycophagous invertebrate community. We highlight characteristics of different soil ecosystems that will give rise to such top-down control. Given the ubiquity of isopods and basidiomycete fungi in temperate and boreal woodland ecosystems, such top-down community control could be of widespread significance for global carbon and nutrient cycling.

  13. Global CO2 Distributions over Land from the Greenhouse Gases Observing Satellite (GOSAT)

    Science.gov (United States)

    Hammerling, Dorit M.; Michalak, Anna M.; O'Dell, Christopher; Kawa, Randolph S.

    2012-01-01

    January 2009 saw the successful launch of the first space-based mission specifically designed for measuring greenhouse gases, the Japanese Greenhouse gases Observing SATellite (GOSAT). We present global land maps (Level 3 data) of column-averaged CO2 concentrations (X(sub CO2)) derived using observations from the GOSAT ACOS retrieval algorithm, for July through December 2009. The applied geostatistical mapping approach makes it possible to generate maps at high spatial and temporal resolutions that include uncertainty measures and that are derived directly from the Level 2 observations, without invoking an atmospheric transport model or estimates of CO2 uptake and emissions. As such, they are particularly well suited for comparison studies. Results show that the Level 3 maps for July to December 2009 on a lO x 1.250 grid, at six-day resolution capture much of the synoptic scale and regional variability of X(sub CO2), in addition to its overall seasonality. The uncertainty estimates, which reflect local data coverage, X(sub CO2) variability, and retrieval errors, indicate that the Southern latitudes are relatively well-constrained, while the Sahara Desert and the high Northern latitudes are weakly-constrained. A probabilistic comparison to the PCTM/GEOS-5/CASA-GFED model reveals that the most statistically significant discrepancies occur in South America in July and August, and central Asia in September to December. While still preliminary, these results illustrate the usefulness of a high spatiotemporal resolution, data-driven Level 3 data product for direct interpretation and comparison of satellite observations of highly dynamic parameters such as atmospheric CO2.

  14. Changes of the potential distribution area of French Mediterranean forests under global warming

    Directory of Open Access Journals (Sweden)

    C. Gaucherel

    2008-11-01

    Full Text Available This work aims at understanding future spatial and temporal distributions of tree species in the Mediterranean region of France under various climates. We focused on two different species (Pinus Halepensis and Quercus Ilex and compared their growth under the IPCC-B2 climate scenario in order to quantify significant changes between present and future. The influence of environmental factors such as atmospheric CO2 increase and topography on the tree growth has also been quantified.

    We modeled species growth with the help of a process-based model (MAIDEN, previously calibrated over measured ecophysiological and dendrochronological series with a Bayesian scheme. The model was fed with the ARPEGE – MeteoFrance climate model, combined with an explicit increase in CO2 atmospheric concentration. The main output of the model gives the carbon allocation in boles and thus tree production.

    Our results show that the MAIDEN model is correctly able to simulate pine and oak production in space and time, after detailed calibration and validation stages. Yet, these simulations, mainly based on climate, are indicative and not predictive. The comparison of simulated growth at end of 20th and 21st centuries, show a shift of the pine production optimum from about 650 to 950 m due to 2.5 K temperature increase, while no optimum has been found for oak. With the direct effect of CO2 increase taken into account, both species show a significant increase in productivity (+26 and +43% for pine and oak respectively at the end of the 21st century.

    While both species have different growth mechanisms, they have a good chance to extend their spatial distribution and their elevation in the Alps during the 21st century under the IPCC-B2 climate scenario. This extension is mainly due to the CO2 fertilization effect.

  15. Challenging the Concept of Natural Distributions: Global Change Turns Trees Into Weeds

    Science.gov (United States)

    Gleadow, R.; O'Leary, B.; Burd, M.

    2015-12-01

    National parks and nature reserves are set aside to preserve certain ecosystems, reflecting species distributions at a moment in time. Changing climate and fire dynamics can mean that the species most suited to that area are different, leading new tree species to 'invade' the conservation areas. Pittosporum undulatum is an invasive tree native tree species with a natural range from southeast Queensland to Eastern Victoria, Australia. Soon after European settlement this species became a popular ornamental tree in gardens and was planted outside of its natural range across the continent and introduced to the USA (where it is known as Victorian Box), the Hawaiian Islands, Jamaica, southern Africa and the Azores. The reason this is important is because high density of P. undulatum lead to reduced biodiversity and often the complete suppression of regeneration of exiting forest trees. In Australia, changes in fire dynamics have played a major part in its in dominance. New strategies for forest management were proposed by Gleadow an Ashton in the 1980s, but lack of action has led us to predict that the entire Dandenong Ranges, near Melbourne, will be invaded within 25 years resulting in the loss of a major recreational and conservation area. This is a model of the type of problems that can be expected as the climate envelope for species changes in the coming century, challenging the very concept of a "native ".

  16. The origin, global distribution, and functional impact of the human 8p23 inversion polymorphism.

    Science.gov (United States)

    Salm, Maximilian P A; Horswell, Stuart D; Hutchison, Claire E; Speedy, Helen E; Yang, Xia; Liang, Liming; Schadt, Eric E; Cookson, William O; Wierzbicki, Anthony S; Naoumova, Rossi P; Shoulders, Carol C

    2012-06-01

    Genomic inversions are an increasingly recognized source of genetic variation. However, a lack of reliable high-throughput genotyping assays for these structures has precluded a full understanding of an inversion's phylogenetic, phenotypic, and population genetic properties. We characterize these properties for one of the largest polymorphic inversions in man (the ∼4.5-Mb 8p23.1 inversion), a structure that encompasses numerous signals of natural selection and disease association. We developed and validated a flexible bioinformatics tool that utilizes SNP data to enable accurate, high-throughput genotyping of the 8p23.1 inversion. This tool was applied retrospectively to diverse genome-wide data sets, revealing significant population stratification that largely follows a clinal "serial founder effect" distribution model. Phylogenetic analyses establish the inversion's ancestral origin within the Homo lineage, indicating that 8p23.1 inversion has occurred independently in the Pan lineage. The human inversion breakpoint was localized to an inverted pair of human endogenous retrovirus elements within the large, flanking low-copy repeats; experimental validation of this breakpoint confirmed these elements as the likely intermediary substrates that sponsored inversion formation. In five data sets, mRNA levels of disease-associated genes were robustly associated with inversion genotype. Moreover, a haplotype associated with systemic lupus erythematosus was restricted to the derived inversion state. We conclude that the 8p23.1 inversion is an evolutionarily dynamic structure that can now be accommodated into the understanding of human genetic and phenotypic diversity.

  17. Tropospheric aerosol size distributions simulated by three online global aerosol models using the M7 microphysics module

    Directory of Open Access Journals (Sweden)

    K. Zhang

    2010-07-01

    Full Text Available Tropospheric aerosol size distributions are simulated by three online global models which employ exactly the same aerosol microphysics module, but differ in many aspects such as model meteorology, natural aerosol emission, sulfur chemistry, and deposition processes. The main purpose of this study is to identify the influence of these differences on the aerosol simulation. Number concentrations of different aerosol size ranges are compared among the three models and against observations. Overall all three models are able to capture the basic features of the observed spatial distribution. The magnitude of number concentration is consistent among the three models in all size ranges, although quantitative differences are also clearly detectable. For the soluble and insoluble coarse and accumulation modes, inter-model discrepancies result primarily from the different parameterization schemes for sea salt and dust emission, and are also linked to the different strengths of the convective transport in the meteorological models. As for the nucleation mode and the soluble Aitken mode, the spread of model results appear largest in the tropics and in the middle and upper troposphere. Diagnostics and sensitivity experiments suggest that this large spread is directly related to the sulfur cycle in the models, which is strongly affected by the choice of sulfur chemistry scheme, its coupling with the convective transport and wet deposition calculation, and the related meteorological fields such as cloud cover, cloud water content, and precipitation. Aerosol size distributions simulated by the three models are compared against observations in the boundary layer. The characteristic shape and magnitude of the distribution functions are reasonably reproduced in typical conditions of clean, polluted and transition areas.

  18. Estimates of Global Rangeland Net Primary Productivity and its Consumption Based on Climate and Livestock Distribution Data

    Science.gov (United States)

    Asrar, G.; Wolf, J.; Rafique, R.; West, T. O.; Ogle, S. M.

    2016-12-01

    Rangelands play an important role in providing ecosystem services such as food, forage, and fuels in many parts of the world. The net primary productivity (NPP), a difference between CO2 fixed by plants and CO2 lost to autotrophic respiration, is a good indicator of the productivity of rangeland ecosystems, and their contribution to the cycling of carbon in the Earth system. In this study, we estimated the NPP of global rangelands, the consumption thereof by grazing livestock, and associated uncertainties, to better understand and quantify the contribution of rangelands to land-based carbon storage. We estimated rangeland NPP using mean annual precipitation data from Climate Research Unit (CRU), and a regression model based on global observations (Del Grosso et al., 2008). Spatial distributions of annual livestock consumption of rangeland NPP (Wolf et al., 2015) were combined with gridded annual rangeland NPP for the years 2000 - 2011. The uncertainty analysis of these estimates was conducted using a Monte Carlo approach. The rangeland NPP estimates with associated uncertainties were also compared with the total modeled GPP estimates obtained from vegetation dynamic model simulations. Our results showed that mean above-ground NPP of rangelands is 1017.5 MgC/km2, while mean below-ground NPP is 847.6 MgC/km2. The total rangeland NPP represents a significant portion of the total NPP of the terrestrial ecosystem. The livestock area requirements used to geographically distribute livestock spatially are based on optimal pasturage and are low relative to area requirements on less productive land. Even so, ca. 90% of annual livestock consumption of rangeland NPP were met with no adjustment of livestock distributions. Moreover, the results of this study allowed us to explicitly quantify the temporal and spatial variations of rangeland NPP under different climatic conditions. Uncertainty analysis was helpful in identifying the strength and weakness of the methods used to

  19. Using WEED to simulate the global wetland distribution in a ESM

    Science.gov (United States)

    Stacke, Tobias; Hagemann, Stefan

    2016-04-01

    Lakes and wetlands are an important land surface feature. In terms of hydrology, they regulate river discharge, mitigate flood events and constitute a significant surface water storage. Considering physical processes, they link the surface water and energy balances by altering the separation of incoming energy into sensible and latent heat fluxes. Finally, they impact biogeochemical processes and may act as carbon sinks or sources. Most global hydrology and climate models regard wetland extent and properties as constant in time. However, to study interactions between wetlands and different states of climate, it is necessary to implement surface water bodies (thereafter referred to as wetlands) with dynamical behavior into these models. Besides an improved representation of geophysical feedbacks between wetlands, land surface and atmosphere, a dynamical wetland scheme could also provide estimates of soil wetness as input for biogeochemical models, which are used to compute methane production in wetlands. Recently, a model for the representation of wetland extent dynamics (WEED) was developed as part of the hydrology model (MPI-HM) of the Max-Planck-Institute for Meteorology (MPI-M). The WEED scheme computes wetland extent in agreement with the range of observations for the high northern latitudes. It simulates a realistic seasonal cycle which shows sensitivity to northern snow-melt as well as rainy seasons in the tropics. Furthermore, flood peaks in river discharge are mitigated. However, the WEED scheme overestimates wetland extent in the Tropics which might be related to the MPI-HM's simplified potential evapotranspiration computation. In order to overcome this limitation, the WEED scheme is implemented into the MPI-M's land surface model JSBACH. Thus, not only its effect on water fluxes can be investigated but also its impact on the energy cycle, which is not included in the MPI-HM. Furthermore, it will be possible to analyze the physical effects of wetlands in a

  20. The global distribution of tropospheric NO{sub x} estimated by a 3-D chemical tracer model

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, A.B.; Rohrer, F.; Ehhalt, D.H. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Atmosphaerische Chemie

    1997-12-31

    The global distribution of NO{sub x} in the troposphere is calculated using a three-dimensional chemical tracer model with a simplified chemistry scheme for the tracers NO{sub x} {identical_to} NO + NO{sub 2} and HNO{sub 3}. At northern mid- and high latitudes, the calculated tropospheric NO{sub x} content is dominated by the surface source fossil fuel combustion. In the tropical free troposphere lightning discharges provide about 80% of the total NO{sub x} throughout the year. The zonally averaged fractional contribution of aircraft emissions strongly depends on season. The NO mixing ratios determined by the model show good overall agreement with corresponding zonal mean values observed during the STRATOZ III aircraft campaign in June. Over Canada, mixing ratios as high as 0.5-1.0 ppbv NO were measured during TROPOZ II, the origin of which is not yet understood. (author) 8 refs.

  1. Analysis of global Terrestrial Gamma Ray Flashes distribution and special focus on AGILE detections over South America

    CERN Document Server

    Fabró, Ferran; Marisaldi, Martino; van der Velde, Oscar A; Fuschino, Fabio

    2016-01-01

    Global distribution of the Terrestrial Gamma-ray Flashes (TGFs) detected by AGILE and RHESSI for the period from March 2009 to July 2012 has been analysed. A fourth TGF production region has been distinguished over the Pacific. It is confirmed that TGF occurrence follows the Intertropical Convergence Zone(ITCZ) seasonal migration and prefers afternoons. TGF/lightning ratio appears to be lower over America than other regions suggesting that meteorological regional differences are important for the TGF production. Diurnal cycle of TGFs peaks in the afternoon suggesting that Convective Available Potential Energy (CAPE) and convection are important for TGF production. Moreover all AGILE passages over South America in the same period have been analysed to find meteorological preferences for TGF occurrence. In each passage the analysis of Cloud Top Altitude (CTA), CAPE, number of strokes, number of storms and coverage area of clouds with temperatures below $-70\\,^{\\circ}{\\rm C}$ (Cloud Top Coverage area, CTC) are c...

  2. Dominant and novel clades of Candidatus Accumulibacter phosphatis in 18 globally distributed full-scale wastewater treatment plants

    Science.gov (United States)

    Mao, Yanping; Graham, David W.; Tamaki, Hideyuki; Zhang, Tong

    2015-07-01

    Here we employed quantitative real-time PCR (qPCR) assays for polyphosphate kinase 1 (ppk1) and 16S rRNA genes to assess relative abundances of dominant clades of Candidatus Accumulibacter phosphatis (referred to Accumulibacter) in 18 globally distributed full-scale wastewater treatment plants (WWTPs) from six countries. Accumulibacter were not only detected in the 6 WWTPs performing biological phosphorus removal, but also inhabited in the other 11 WWTPs employing conventional activated sludge (AS) with abundances ranging from 0.02% to 7.0%. Among the AS samples, clades IIC and IID were found to be dominant among the five Accumulibacter clades. The relative abundance of each clade in the Accumulibacter lineage significantly correlated (p biological phosphorus removal (EBPR) WWTPs. The results deepened our understanding of the Accumulibacter diversity in environmental samples.

  3. Applicability of pion–nucleus Drell–Yan data in global analysis of nuclear parton distribution functions

    Energy Technology Data Exchange (ETDEWEB)

    Paakkinen, Petja, E-mail: petja.paakkinen@jyu.fi [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Eskola, Kari J., E-mail: kari.eskola@jyu.fi [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Helsinki Institute of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Paukkunen, Hannu, E-mail: hannu.paukkunen@jyu.fi [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Helsinki Institute of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Instituto Galego de Física de Altas Enerxías (IGFAE), Universidade de Santiago de Compostela, E-15782 Galicia (Spain)

    2017-05-10

    Despite the success of modern nuclear parton distribution functions (nPDFs) in describing nuclear hard-process data, they still suffer from large uncertainties. One of the poorly constrained features is the possible asymmetry in nuclear modifications of valence u and d quarks. We study the possibility of using pion–nucleus Drell–Yan dilepton data as a new constraint in the global analysis of nPDFs. We find that the nuclear cross-section ratios from the NA3, NA10 and E615 experiments can be used without imposing significant new theoretical uncertainties and, in particular, that these datasets may have some constraining power on the u/d-asymmetry in nuclei.

  4. Life cycle analysis of distributed concentrating solar combined heat and power: economics, global warming potential and water

    Science.gov (United States)

    Norwood, Zack; Kammen, Daniel

    2012-12-01

    We report on life cycle assessment (LCA) of the economics, global warming potential and water (both for desalination and water use in operation) for a distributed concentrating solar combined heat and power (DCS-CHP) system. Detailed simulation of system performance across 1020 sites in the US combined with a sensible cost allocation scheme informs this LCA. We forecast a levelized cost of 0.25 kWh-1 electricity and 0.03 kWh-1 thermal, for a system with a life cycle global warming potential of ˜80 gCO2eq kWh-1 of electricity and ˜10 gCO2eq kWh-1 thermal, sited in Oakland, California. On the basis of the economics shown for air cooling, and the fact that any combined heat and power system reduces the need for cooling while at the same time boosting the overall solar efficiency of the system, DCS-CHP compares favorably to other electric power generation systems in terms of minimization of water use in the maintenance and operation of the plant. The outlook for water desalination coupled with distributed concentrating solar combined heat and power is less favorable. At a projected cost of 1.40 m-3, water desalination with DCS-CHP would be economical and practical only in areas where water is very scarce or moderately expensive, primarily available through the informal sector, and where contaminated or salt water is easily available as feed-water. It is also interesting to note that 0.40-1.90 m-3 is the range of water prices in the developed world, so DCS-CHP desalination systems could also be an economical solution there under some conditions.

  5. Global Infrared–Radio Spectral Energy Distributions of Galactic Massive Star-Forming Regions

    Science.gov (United States)

    Povich, Matthew Samuel; Binder, Breanna Arlene

    2018-01-01

    We present a multiwavelength study of 30 Galactic massive star-forming regions. We fit multicomponent dust, blackbody, and power-law continuum models to 3.6 µm through 10 mm spectral energy distributions obtained from Spitzer, MSX, IRAS, Herschel, and Planck archival survey data. Averaged across our sample, ~20% of Lyman continuum photons emitted by massive stars are absorbed by dust before contributing to the ionization of H II regions, while ~50% of the stellar bolometric luminosity is absorbed and reprocessed by dust in the H II regions and surrounding photodissociation regions. The most luminous, infrared-bright regions that fully sample the upper stellar initial mass function (ionizing photon rates NC ≥ 1050 s–1 and total infrared luminosity LTIR ≥ 106.8 L⊙) have higher percentages of absorbed Lyman continuum photons (~40%) and dust-reprocessed starlight (~80%). The monochromatic 70-µm luminosity L70 is linearly correlated with LTIR, and on average L70/LTIR = 50%, in good agreement with extragalactic studies. Calibrated against the known massive stellar content in our sampled H II regions, we find that star formation rates based on L70 are in reasonably good agreement with extragalactic calibrations, when corrected for the smaller physical sizes of the Galactic regions. We caution that absorption of Lyman continuum photons prior to contributing to the observed ionizing photon rate may reduce the attenuation-corrected Hα emission, systematically biasing extragalactic calibrations toward lower star formation rates when applied to spatially-resolved studies of obscured star formation.This work was supported by the National Science Foundation under award CAREER-1454333.

  6. Species distribution models and impact factor growth in environmental journals: methodological fashion or the attraction of global change science.

    Science.gov (United States)

    Brotons, Lluís

    2014-01-01

    In this work, I evaluate the impact of species distribution models (SDMs) on the current status of environmental and ecological journals by asking the question to which degree development of SDMs in the literature is related to recent changes in the impact factors of ecological journals. The hypothesis evaluated states that research fronts are likely to attract research attention and potentially drive citation patterns, with journals concentrating papers related to the research front receiving more attention and benefiting from faster increases in their impact on the ecological literature. My results indicate a positive relationship between the number of SDM related articles published in a journal and its impact factor (IF) growth during the period 2000-09. However, the percentage of SDM related papers in a journal was strongly and positively associated with the percentage of papers on climate change and statistical issues. The results support the hypothesis that global change science has been critical in the development of SDMs and that interest in climate change research in particular, rather than the usage of SDM per se, appears as an important factor behind journal IF increases in ecology and environmental sciences. Finally, our results on SDM application in global change science support the view that scientific interest rather than methodological fashion appears to be the major driver of research attraction in the scientific literature.

  7. A simulation of the global distribution and radiative forcing of soil dust aerosols at the Last Glacial Maximum

    Directory of Open Access Journals (Sweden)

    T. Takemura

    2009-05-01

    Full Text Available In this study an integrated simulation of the global distribution and the radiative forcing of soil dust aerosols at the Last Glacial Maximum (LGM is performed with an aerosol climate model, SPRINTARS. It is compared with another simulation for the present climate condition. The global total emission flux of soil dust aerosols at the LGM is simulated to be about 2.4 times as large as that in the present climate, and the simulated deposition flux is in general agreement with estimations from ice core and marine sediment samplings though it appears to be underestimated over the Antarctic. The calculated direct radiative forcings of soil dust aerosols at the LGM is close to zero at the tropopause and −0.4 W m−2 at the surface. These radiative forcings are about twice as large as those in the present climate. SPRINTARS also includes the microphysical parameterizations of the cloud-aerosol interaction both for liquid water and ice crystals, which affect the radiation budget. The positive radiative forcing from the indirect effect of soil dust aerosols is mainly caused by their properties to act as ice nuclei. This effect is simulated to be smaller (−0.9 W m−2 at the LGM than in the present. It is suggested that atmospheric dust might contribute to the cold climate during the glacial periods both through the direct and indirect effects, relative to the interglacial periods.

  8. Global data bases on distribution, characteristics and methane emission of natural wetlands: Documentation of archived data tape

    Science.gov (United States)

    Matthews, Elaine

    1989-01-01

    Global digital data bases on the distribution and environmental characteristics of natural wetlands, compiled by Matthews and Fung (1987), were archived for public use. These data bases were developed to evaluate the role of wetlands in the annual emission of methane from terrestrial sources. Five global 1 deg latitude by 1 deg longitude arrays are included on the archived tape. The arrays are: (1) wetland data source, (2) wetland type, (3) fractional inundation, (4) vegetation type, and (5) soil type. The first three data bases on wetland locations were published by Matthews and Fung (1987). The last two arrays contain ancillary information about these wetland locations: vegetation type is from the data of Matthews (1983) and soil type from the data of Zobler (1986). Users should consult original publications for complete discussion of the data bases. This short paper is designed only to document the tape, and briefly explain the data sets and their initial application to estimating the annual emission of methane from natural wetlands. Included is information about array characteristics such as dimensions, read formats, record lengths, blocksizes and value ranges, and descriptions and translation tables for the individual data bases.

  9. Species distribution models and impact factor growth in environmental journals: methodological fashion or the attraction of global change science.

    Directory of Open Access Journals (Sweden)

    Lluís Brotons

    Full Text Available In this work, I evaluate the impact of species distribution models (SDMs on the current status of environmental and ecological journals by asking the question to which degree development of SDMs in the literature is related to recent changes in the impact factors of ecological journals. The hypothesis evaluated states that research fronts are likely to attract research attention and potentially drive citation patterns, with journals concentrating papers related to the research front receiving more attention and benefiting from faster increases in their impact on the ecological literature. My results indicate a positive relationship between the number of SDM related articles published in a journal and its impact factor (IF growth during the period 2000-09. However, the percentage of SDM related papers in a journal was strongly and positively associated with the percentage of papers on climate change and statistical issues. The results support the hypothesis that global change science has been critical in the development of SDMs and that interest in climate change research in particular, rather than the usage of SDM per se, appears as an important factor behind journal IF increases in ecology and environmental sciences. Finally, our results on SDM application in global change science support the view that scientific interest rather than methodological fashion appears to be the major driver of research attraction in the scientific literature.

  10. The impact of organochlorines cycling in the cryosphere on global distributions and fate--2. Land ice and temporary snow cover.

    Science.gov (United States)

    Hofmann, Lorenz; Stemmler, Irene; Lammel, Gerhard

    2012-03-01

    Global fate and transport of γ-HCH and DDT was studied using a global multicompartment chemistry-transport model, MPI-MCTM, with and without inclusion of land ice (in Antarctica and Greenland) or snow cover (dynamic). MPI-MCTM is based on coupled ocean and atmosphere general circulation models. After a decade of simulation 4.2% γ-HCH and 2.3% DDT are stored in land ice and snow. Neglection of land ice and snow in modelling would underestimate the total environmental residence time, τ(ov), of γ-HCH and overestimate τ(ov) for DDT, both on the order of 1% and depending on actual compartmental distribution. Volatilisation of DDT from boreal, seasonally snow covered land is enhanced throughout the year, while volatilisation of γ-HCH is only enhanced during the snow-free season. Including land ice and snow cover in modelling matters in particular for the Arctic, where higher burdens are predicted to be stored. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Changes in species richness and spatial distribution of mosquitoes (Diptera: Culicidae) inferred from museum specimen records and a recent inventory: a case study from Belgium suggests recent expanded distribution of arbovirus and malaria vectors.

    Science.gov (United States)

    Dekoninck, W; Hendrickx, F; Versteirt, V; Coosemans, M; De Clercq, E M; Hendrickx, G; Hance, T; Grootaert, P

    2013-03-01

    Mosquito (Diptera: Culicidae) distribution data from a recent inventory of native and invading mosquito species in Belgium were compared with historical data from the period 1900-1960 that were retrieved from a revision of the Belgian Culicidae collection at the Royal Belgian Institute of Natural Sciences. Both data sets were used to investigate trends in mosquito species richness in several regions in Belgium. The relative change in distribution area of mosquito species was particularly important for species that use waste waters and used tires as larval habitats and species that recently shifted their larval habitat to artificial larval habitats. More importantly, several of these species are known as vectors of arboviruses and Plasmodium sp. and the apparent habitat shift of some of them brought these species in proximity to humans. Similar studies comparing current mosquito richness with former distribution data retrieved from voucher specimens from collections is therefore encouraged because they can generate important information concerning health risk assessment at both regional and national scale.

  12. Predicting 21st-century polar bear habitat distribution from global climate models

    Science.gov (United States)

    Durner, G.M.; Douglas, D.C.; Nielson, R.M.; Amstrup, Steven C.; McDonald, T.L.; Stirling, I.; Mauritzen, Mette; Born, E.W.; Wiig, O.; Deweaver, E.; Serreze, M.C.; Belikov, Stanislav; Holland, M.M.; Maslanik, J.; Aars, Jon; Bailey, D.A.; Derocher, A.E.

    2009-01-01

    Projections of polar bear (Ursus maritimus) sea ice habitat distribution in the polar basin during the 21st century were developed to understand the consequences of anticipated sea ice reductions on polar bear populations. We used location data from satellitecollared polar bears and environmental data (e.g., bathymetry, distance to coastlines, and sea ice) collected from 1985 to 1995 to build resource selection functions (RSFs). RSFs described habitats that polar bears preferred in summer, autumn, winter, and spring. When applied to independent data from 1996 to 2006, the RSFs consistently identified habitats most frequently used by polar bears. We applied the RSFs to monthly maps of 21st-century sea ice concentration projected by 10 general circulation models (GCMs) used in the Intergovernmental Panel of Climate Change Fourth Assessment Report, under the A1B greenhouse gas forcing scenario. Despite variation in their projections, all GCMs indicated habitat losses in the polar basin during the 21st century. Losses in the highest-valued RSF habitat (optimal habitat) were greatest in the southern seas of the polar basin, especially the Chukchi and Barents seas, and least along the Arctic Ocean shores of Banks Island to northern Greenland. Mean loss of optimal polar bear habitat was greatest during summer; from an observed 1.0 million km2 in 1985-1995 (baseline) to a projected multi-model mean of 0.32 million km2 in 2090-2099 (-68% change). Projected winter losses of polar bear habitat were less: from 1.7 million km2 in 1985-1995 to 1.4 million km2 in 2090-2099 (-17% change). Habitat losses based on GCM multi-model means may be conservative; simulated rates of habitat loss during 1985-2006 from many GCMs were less than the actual observed rates of loss. Although a reduction in the total amount of optimal habitat will likely reduce polar bear populations, exact relationships between habitat losses and population demographics remain unknown. Density and energetic

  13. Infrastructure Requirements for an Expanded Fuel Ethanol Industry

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, Robert E. [Downstream Alternatives, Inc., South Bend, IN (United States)

    2002-01-15

    This report provides technical information specifically related to ethanol transportation, distribution, and marketing issues. This report required analysis of the infrastructure requirements for an expanded ethanol industry.

  14. Data-mining analysis of the global distribution of soil carbon in observational databases and Earth system models

    Science.gov (United States)

    Hashimoto, Shoji; Nanko, Kazuki; Ťupek, Boris; Lehtonen, Aleksi

    2017-03-01

    Future climate change will dramatically change the carbon balance in the soil, and this change will affect the terrestrial carbon stock and the climate itself. Earth system models (ESMs) are used to understand the current climate and to project future climate conditions, but the soil organic carbon (SOC) stock simulated by ESMs and those of observational databases are not well correlated when the two are compared at fine grid scales. However, the specific key processes and factors, as well as the relationships among these factors that govern the SOC stock, remain unclear; the inclusion of such missing information would improve the agreement between modeled and observational data. In this study, we sought to identify the influential factors that govern global SOC distribution in observational databases, as well as those simulated by ESMs. We used a data-mining (machine-learning) (boosted regression trees - BRT) scheme to identify the factors affecting the SOC stock. We applied BRT scheme to three observational databases and 15 ESM outputs from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) and examined the effects of 13 variables/factors categorized into five groups (climate, soil property, topography, vegetation, and land-use history). Globally, the contributions of mean annual temperature, clay content, carbon-to-nitrogen (CN) ratio, wetland ratio, and land cover were high in observational databases, whereas the contributions of the mean annual temperature, land cover, and net primary productivity (NPP) were predominant in the SOC distribution in ESMs. A comparison of the influential factors at a global scale revealed that the most distinct differences between the SOCs from the observational databases and ESMs were the low clay content and CN ratio contributions, and the high NPP contribution in the ESMs. The results of this study will aid in identifying the causes of the current mismatches between observational SOC databases and ESM outputs

  15. The influence of climate change on the global distribution and fate processes of anthropogenic persistent organic pollutants.

    Science.gov (United States)

    Kallenborn, Roland; Halsall, Crispin; Dellong, Maud; Carlsson, Pernilla

    2012-11-01

    The effect of climate change on the global distribution and fate of persistent organic pollutants (POPs) is of growing interest to both scientists and policy makers alike. The impact of warmer temperatures and the resulting changes to earth system processes on chemical fate are, however, unclear, although there are a growing number of studies that are beginning to examine these impacts and changes in a quantitative way. In this review, we examine broad areas where changes are occurring or are likely to occur with regard to the environmental cycling and fate of chemical contaminants. For this purpose we are examining scientific information from long-term monitoring data with particular emphasis on the Arctic, to show apparent changes in chemical patterns and behaviour. In addition, we examine evidence of changing chemical processes for a number of environmental compartments and indirect effects of climate change on contaminant emissions and behaviour. We also recommend areas of research to address knowledge gaps. In general, our findings indicate that the indirect consequences of climate change (i.e. shifts in agriculture, resource exploitation opportunities, etc.) will have a more marked impact on contaminants distribution and fate than direct climate change.

  16. High-Resolution Vector Magnetograms of the Sun's Poles from Hinode: Flux Distributions and Global Coronal Modeling

    Science.gov (United States)

    Petrie, Gordon

    2017-01-01

    The Sun's polar fields play a leading role in structuring the large-scale solar atmosphere and in determining the interplanetary magnetic field. They are also believed to supply the seed field for the subsequent solar activity cycle. However, present-day synoptic observations do not have sufficient spatial resolution or sensitivity to diagnose accurately the high-latitude magnetic vector field. The high spatial resolution and sensitivity of the full-Stokes observations from the Hinode Solar Optical Telescope Spectro-Polarimeter, observing the poles long-term, allows us to build up a detailed picture of the Cycle 24 polar field reversal, including the changing latitude distribution of the high-latitude flux, and to study the effect on global coronal field models. The Hinode observations provide detailed information on the dominant facular-scale magnetic structure of the polar fields, and their field inclination and flux distribution. Hybrid synoptic magnetograms are constructed from Hinode polar measurements and full-disk magnetograms from the Synoptic Optical Long-term Investigations of the Sun (SOLIS) Vector Spectro-Magnetograph (VSM), and coronal potential field models are calculated. Loss of effective spatial resolution at the highest latitudes presents complications. Possible improvements to synoptic polar data are discussed.

  17. Predicting the Global Potential Distribution of Four Endangered Panax Species in Middle-and Low-Latitude Regions of China by the Geographic Information System for Global Medicinal Plants (GMPGIS).

    Science.gov (United States)

    Du, Zhixia; Wu, Jie; Meng, Xiangxiao; Li, Jinhua; Huang, Linfang

    2017-09-28

    Global biodiversity is strongly influenced by the decrease in endangered biological species. Predicting the distribution of endangered medicinal plants is necessary for resource conservation. A spatial distribution model-geographic information system for global medicinal plants (GMPGIS)-is used to predict the global potential suitable distribution of four endangered Panax species, including Panax japonicas (T. Nees) C. A. Meyer and Panax japonicas var. major (Burkill) C. Y. Wu & K. M. Feng distributed in low- and middle-latitude, Panax zingiberensis C. Y. Wu & K. M. Feng and Panax stipuleanatus C. T. Tsai & K. M. Feng in low-latitude regions of China based on seven bioclimatic variables and 600 occurrence points. Results indicate that areas of P. japonicus and P. japonicusvar. major are 266.29 × 10⁵ and 77.5 × 10⁵ km², respectively, which are mainly distributed in China and America. By contrast, the areas of P. zingiberensis and P. stipuleanatus are 5.09 × 10⁵ and 2.05 × 10⁵ km², respectively, which are mainly distributed in Brazil and China. P. japonicus has the widest distribution among the four species. The data also indicate that the mean temperature of coldest quarter is the most critical factor. This scientific prediction can be used as reference for resource conservation of endangered plants and as a guide to search for endangered species in previously unknown areas.

  18. Expanding Thurston maps

    CERN Document Server

    Bonk, Mario

    2017-01-01

    This monograph is devoted to the study of the dynamics of expanding Thurston maps under iteration. A Thurston map is a branched covering map on a two-dimensional topological sphere such that each critical point of the map has a finite orbit under iteration. It is called expanding if, roughly speaking, preimages of a fine open cover of the underlying sphere under iterates of the map become finer and finer as the order of the iterate increases. Every expanding Thurston map gives rise to a fractal space, called its visual sphere. Many dynamical properties of the map are encoded in the geometry of this visual sphere. For example, an expanding Thurston map is topologically conjugate to a rational map if and only if its visual sphere is quasisymmetrically equivalent to the Riemann sphere. This relation between dynamics and fractal geometry is the main focus for the investigations in this work.

  19. ICT AND THE CHANGING LANDSCAPE OF TOURISM DISTRIBUTION- A NEW DIMENSION OF TOURISM IN THE GLOBAL CONDITIONS

    Directory of Open Access Journals (Sweden)

    Kozeta SEVRANI

    2008-06-01

    Full Text Available The travel and tourism sector has emerged as one of the most important sectors for developing as well as developed countries. Tourism incorporates many of the features of the information society such as globalization, mobility and information richness. People from all nations, social rank, and professions are potential tourists. Tourism links a worldwide supplier community with consumers, equally distributed worldwide. Its physical and virtual networks enable worldwide travelling, bringing together very distant cultures and habits. The industry is diverse; the size of tourism principals varies from micro to global enterprises. While some are fragmented, other parts, like the airlines, are concentrated into an oligopoly of global alliances. Information systems (IS in tourism have been among the pioneers of leading edge technology applications: Computer Reservation Systems (CRS or Global Distribution Systems (GDS have been among the first international inter-organizational systems. Yield management systems are among the most advanced data mining applications. Tourism marketing systems typically represent the forefront of multimedia and virtual-reality applications. The World Wide Web is profoundly changing the production, distribution and consumption of touristic products. Information and communication technology (ICT is probably the strongest driving force for changes within the tourism industry. Both industries are not only growing above average, they will also be among the most important industries in this century. Being closely interrelated and intertwined. The first part of the paper presents a structural view, identifying the different types of players, the nature of the tourism business and tourism product. The second part gives a general introduction to the relationship between ICT and tourism and provides some empirical evidence of importance of tourism in the e-commerce sector. Part three gives a

  20. Age and transit time distributions of carbon in a nonlinear global model perturbed by nonautonomous fossil-fuel emissions signals

    Science.gov (United States)

    Metzler, Holger; Müller, Markus; Sierra, Carlos A.

    2017-04-01

    Carbon fluxes in the ocean-atmosphere-biosphere system are governed by nonlinear processes, which are usually modeled by a system of ordinary differential equations. It is very difficult to analyze such nonlinear models and to predict their future behavior, particularly their internal age structure: How old is the carbon in different pools (ages) and how old is the carbon that leaves the system (transit times)? How is this age structure modified by the addition of fossil fuel emissions? To answer these questions, we developed a new mathematical approach that allows us to compute and visualize the age structure of models of well mixed pools even if they are nonlinear and nonautonomous. We do not only consider mean ages and mean transit times, but entire distributions. Consequently, we can consider important statistics such as the median, quantiles, or the variance. We applied this mathematical approach to a nonlinear global carbon model consisting of three pools (atmosphere, surface ocean, and terrestrial biosphere) and driven by four emission scenarios (RCP3-PD, RCP4.5, RCP6, RCP8.5). Results showed that the addition of fossil fuels modifies the age structure of C in the atmosphere by drastically increasing its proportion of young carbon. We found little differences among predicted mean ages for the four emission scenarios, but changes in the overall distributions were large with effects on median, quantiles and variance. In the short-term, fossil-fuel emissions have an important effect on the amount of carbon that is exchanged among Earth's main C reservoirs. In the long-term, most added C will eventually end up in the deep ocean, but the time required to return to pre-industrial C age distributions is largely dependent on emission scenarios.

  1. SVD identifies transcript length distribution functions from DNA microarray data and reveals evolutionary forces globally affecting GBM metabolism.

    Directory of Open Access Journals (Sweden)

    Nicolas M Bertagnolli

    Full Text Available To search for evolutionary forces that might act upon transcript length, we use the singular value decomposition (SVD to identify the length distribution functions of sets and subsets of human and yeast transcripts from profiles of mRNA abundance levels across gel electrophoresis migration distances that were previously measured by DNA microarrays. We show that the SVD identifies the transcript length distribution functions as "asymmetric generalized coherent states" from the DNA microarray data and with no a-priori assumptions. Comparing subsets of human and yeast transcripts of the same gene ontology annotations, we find that in both disparate eukaryotes, transcripts involved in protein synthesis or mitochondrial metabolism are significantly shorter than typical, and in particular, significantly shorter than those involved in glucose metabolism. Comparing the subsets of human transcripts that are overexpressed in glioblastoma multiforme (GBM or normal brain tissue samples from The Cancer Genome Atlas, we find that GBM maintains normal brain overexpression of significantly short transcripts, enriched in transcripts that are involved in protein synthesis or mitochondrial metabolism, but suppresses normal overexpression of significantly longer transcripts, enriched in transcripts that are involved in glucose metabolism and brain activity. These global relations among transcript length, cellular metabolism and tumor development suggest a previously unrecognized physical mode for tumor and normal cells to differentially regulate metabolism in a transcript length-dependent manner. The identified distribution functions support a previous hypothesis from mathematical modeling of evolutionary forces that act upon transcript length in the manner of the restoring force of the harmonic oscillator.

  2. Expanding CTE Opportunities through Blended Learning

    Science.gov (United States)

    McKinstry, Elizabeth

    2012-01-01

    The global economy, 21st century skills, knowledge society, college and career readiness, digital and project-based learning are all common terms to educators who are expanding their learning environments beyond the classroom to meet the needs of all students. It is common knowledge that the rapid technological advances of this century have…

  3. Sensitivity of remote aerosol distributions to representation of cloud-aerosol interactions in a global climate model

    Science.gov (United States)

    Wang, H.; Easter, R. C.; Rasch, P. J.; Wang, M.; Liu, X.; Ghan, S. J.; Qian, Y.; Yoon, J.-H.; Ma, P.-L.; Vinoj, V.

    2013-06-01

    Arctic winter (summer) BC burden. This BC aging treatment, however, has minimal effect on other underpredicted species. Interestingly, our modifications to CAM5 that aim at improving prediction of high-latitude and upper-tropospheric aerosols also produce much-better aerosol optical depth (AOD) over various other regions globally when compared to multi-year AERONET retrievals. The improved aerosol distributions have impacts on other aspects of CAM5, improving the simulation of global mean liquid water path and cloud forcing.

  4. Silicon microfabricated beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Othman, A., E-mail: aliman@ppinang.uitm.edu.my; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A. [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40450, Shah Alam, Selangor (Malaysia); Ain, M. F. [School of Electrical and Electronic Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300,Nibong Tebal, Pulau Pinang (Malaysia)

    2015-03-30

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed.

  5. TRIPLE ACTION PALATE EXPANDER

    Directory of Open Access Journals (Sweden)

    Svetlana Yordanova

    2011-09-01

    Full Text Available Malocclusion correction essentially involves expansion of the maxilla, protrusion of anterior teeth and opening the bite. Expansion is often the stage preceding the treatment with fixed appliances. The elevation of the occlusion using accomplished with different devices (bite planes -fixed or removable, composite material on the occlusall surface of molars carries the risk of breaking or debonding them.The present article proposes an expanding appliance with triple action as a therapeutic means of choice in an orthodontic treatment with fixed appliances. The expander can simultaneously be used to protrude upper teeth, to expand the upper jaw and disarticulate the occlusion. It can be easily fabricated in clinical conditions, causes no discomfort and does not hamper oral hygiene because it can be removed and cleaned.

  6. Distributed Drug Discovery, Part 2: Global Rehearsal of Alkylating Agents for the Synthesis of Resin-Bound Unnatural Amino Acids and Virtual D3 Catalog Construction

    OpenAIRE

    William L. Scott; Alsina, Jordi; Audu, Christopher O.; Babaev, Evgenii; Cook, Linda; Dage, Jeffery L.; Goodwin, Lawrence A.; Martynow, Jacek G.; Matosiuk, Dariusz; Royo, Miriam; Smith, Judith G.; Strong, Andrew T.; Wickizer, Kirk; Woerly, Eric M.; Zhou, Ziniu

    2008-01-01

    Distributed Drug Discovery (D3) proposes solving large drug discovery problems by breaking them into smaller units for processing at multiple sites. A key component of the synthetic and computational stages of D3 is the global rehearsal of prospective reagents and their subsequent use in the creation of virtual catalogs of molecules accessible by simple, inexpensive combinatorial chemistry. The first section of this article documents the feasibility of the synthetic component of Distributed D...

  7. The effect of Global Postural Reeducation on body weight distribution in sitting posture and on musculoskeletal pain. A pilot study.

    Science.gov (United States)

    De Lima E Sá Resende, Fernanda; Vanti, Carla; Banchelli, Federico; Trani Brandao, José Geraldo; Oliveira Amorim, José Benedito; Villafañe, Jorge Hugo; Guccione, Andrew; Pillastrini, Paolo

    2017-06-28

    To quantify body weight distribution (BWD) in seated posture with an office chair instrumented with load cells and to evaluate the effects of ergonomic advice and Global Postural Reeducation (GPR) on seated BWD and on musculoskeletal pain. Nineteen healthy females were randomly assigned: nine to the experimental group and 10 to the control group. Control group (CG) received only ergonomic verbal advice (EVA) regarding BWD in a seated position. Experimental group (EG) also received EVA and furthermore attended eight GPR sessions. Difference in the effects of the different therapeutic approaches was investigated using the non-parametric Wilcoxon-Mann-Whitney test. After treatments, there was no significant difference between the two groups as regards seated BWD. EG improved musculoskeletal pain significantly more than CG (p<0.005). Instead, musculoskeletal pain frequency decreased (p<0.005) only in EG (after EVA and GPR sessions), in neck, cervical, thoracic, lumbar, shoulders and wrists areas. Despite both interventions did not induce any significant improvement on seated BWD, adding GPR to EVA was related to a better reduction on musculoskeletal pain in young health females.

  8. Spatiotemporal Distribution of Droughts in the Xijiang River Basin, China and Its Responses to Global Climatic Events

    Directory of Open Access Journals (Sweden)

    Jizhong Qiu

    2017-04-01

    Full Text Available The Xijiang River is a main branch of the Pearl River, the largest river in South China. Droughts in this area have seriously influenced local water resource utilization, and socio-economic development. The spatiotemporal distribution of droughts and its responses to global climatic events are of critical significance for the assessment and early warning of drought disasters. In this paper, the spatiotemporal patterns of droughts characterized by Rotated Empirical Orthogonal Function/Rotated Principal Components (REOF/RPC in the Xijiang River Basin, China were evaluated using the Self-calibrated Palmer Drought Severity Index (Sc-PDSI. The drought responses to El Niño/Southern Oscillation (ENSO, Pacific Decadal Oscillation (PDO, India Ocean Dipole (IOD, and North Atlantic Oscillation (NAO were analysed by Pearson correlation and multiple stepwise regression. The results showed that one year earlier NAO was the dominant factor impacting the droughts in the Xijiang Basin. Its contribution for the RPC2s of the annual, the first and second half years, winter, summer, autumn, and February were −0.556, −0.419, 0.597, −0.447, 0.542, 0.600, and −0.327, respectively. Besides the two adjacent Pacific and India oceans, the droughts seem be influenced by distant Atlantic climatic events. These results offer new reference insights into the early warning of droughts as well as the planning and management of water resources in the study area.

  9. Atmospheric Inversion of the Global Surface Carbon Flux with Consideration of the Spatial Distributions of US Crop Production and Consumption

    Science.gov (United States)

    Fung, Jonathan Winston

    Carbon dioxide is taken up by crops during production and released back to the atmosphere at different geographical locations through respiration of consumed crop commodities. In this study, spatially distributed county-level US cropland net primary productivity, harvested biomass, changes in soil carbon, and human and livestock consumption data were integrated into the prior terrestrial biosphere flux generated by the Boreal Ecosystem Productivity Simulator (BEPS). A global time-dependent Bayesian synthesis inversion with a nested focus on North America was carried out based on CO2 observations at 210 stations. Overall, the inverted annual North American CO2 sink weakened by 6.5% over the period from 2002 to 2007 compared to simulations disregarding US crop statistical data. The US Midwest is found to be the major sink of 0.36±0.13 PgC yr-1 whereas the large sink in the US Southeast forests weakened to 0.16±0.12 PgC yr-1 partly due to local CO2 sources from crop consumption.

  10. Global measurements of coarse-mode aerosol size distributions - first results from the Atmospheric Tomography Mission (ATom)

    Science.gov (United States)

    Weinzierl, B.; Dollner, M.; Schuh, H.; Brock, C. A.; Bui, T. V.; Gasteiger, J.; Froyd, K. D.; Schwarz, J. P.; Spanu, A.; Murphy, D. M.; Katich, J. M.; Kupc, A.; Williamson, C.

    2016-12-01

    Although coarse-mode aerosol (>1 µm diameter), composed mainly of mineral dust and sea-salt, is highly abundant over large regions of the world, these particles form a particularly poorly understood and characterized subset of atmospheric aerosol constituents. The NASA-sponsored Atmospheric Tomography Mission (ATom) is an unprecedented field program that investigates how human emissions affect air quality and climate change. ATom provides a singular opportunity to characterize the global coarse-mode size distribution by continuously profiling between 0.2 and 13 km with the NASA DC-8 research aircraft while traveling from the high Arctic down south the middle of the Pacific Ocean, to the Southern Ocean and back north over the Atlantic Ocean basin in four seasons. For ATom, the DC-8 aircraft has been equipped with multiple instruments to observe the composition of the air. The coarse mode and cloud particle size distribution is measured in-situ with a Cloud, Aerosol, and Precipitation Spectrometer (CAPS) mounted under the wing of the DC-8 research aircraft. The CAPS consists of an optical spectrometer providing size distributions in the size range between 0.5 and 50 µm and an imager detecting number concentration, size and shape of particles between 15 and 930 µm diameter. Early ATom flights indicated complicated vertical layering: over the sea, we regularly observed sea salt aerosol which extended from the ground up to 0.6-1 km altitude. In addition - depending on the location of the measurements - we frequently found layers with coarse mode aerosol originating from deserts and biomass burning aerosol aloft. In this study, we will present first results of coarse mode aerosol observations from the entire first ATom deployment in summer 2016. We will show vertical profiles of coarse mode aerosol number concentration, discuss their interhemispheric differences, and look into the question how frequently coarse-mode aerosol is externally mixed with submicron black

  11. Expandable gastroretentive dosage forms.

    Science.gov (United States)

    Klausner, Eytan A; Lavy, Eran; Friedman, Michael; Hoffman, Amnon

    2003-06-24

    Expandable gastroretentive dosage forms (GRDFs) have been designed for the past 3 decades. They were originally created for possible veterinary use, but later the design was modified for enhanced drug therapy in humans. These GRDFs are easily swallowed and reach a significantly larger size in the stomach due to swelling or unfolding processes that prolong their gastric retention time (GRT). After drug release, their dimensions are minimized with subsequent evacuation from the stomach. Gastroretentivity is enhanced by the combination of substantial dimensions with high rigidity of the dosage form to withstand the peristalsis and mechanical contractility of the stomach. Positive results were obtained in preclinical and clinical studies evaluating GRT of expandable GRDFs. Narrow absorption window drugs compounded in such systems have improved in vivo absorption properties. These findings are an important step towards the implementation of expandable GRDFs in the clinical setting. The current review deals with expandable GRDFs reported in articles and patents, and describes the physiological basis of their design. Using the dog as a preclinical screening model prior to human studies, relevant imaging techniques and pharmacokinetic-pharmacodynamic aspects of such delivery systems are also discussed.

  12. A theory of local and global processes which affect solar wind electrons. 1: The origin of typical 1 AU velocity distribution functions: Steady state theory

    Science.gov (United States)

    Scudder, J. D.

    1978-01-01

    A detailed first principle kinetic theory for electrons which is neither a classical fluid treatment nor an exospheric calculation is presented. This theory illustrates the global and local properties of the solar wind expansion that shape the observed features of the electron distribution function, such as its bifurcation, its skewness and the differential temperatures of the thermal and suprathermal subpopulations. Coulomb collisions are substantial mediators of the interplanetary electron velocity distribution function and they place a zone for a bifurcation of the electron distribution function deep in the corona. The local cause and effect precept which permeates the physics of denser media is modified for electrons in the solar wind. The local form of transport laws and equations of state which apply to collision dominated plasmas are replaced with global relations that explicitly depend on the relative position of the observer to the boundaries of the system.

  13. Global stratospheric hydrogen peroxide distribution from MIPAS-Envisat full resolution spectra compared to KASIMA model results

    Directory of Open Access Journals (Sweden)

    S. Versick

    2012-06-01

    Full Text Available MIPAS-ENVISAT full resolution spectra were analyzed to obtain a global distribution of hydrogen peroxide (H2O2 in the stratosphere. H2O2 acts as reservoir gas for the HOx family (= H+OH+HO2 and thus, observations of H2O2 provide a better understanding of the HOx chemistry in the atmosphere. A retrieval approach based on constrained least squares fitting was developed and applied to small dedicated spectral analysis windows with maximum H2O2 information and minimum contribution of interfering gases. Due to a low signal to noise ratio in the measured spectra single profiles cannot be used for scientific interpretation and about 100 profiles have to be averaged temporally or spatially. Our retrievals of H2O2 from MIPAS measurements provide meaningful results between approximately 20 and 60 km. A possible impact by the high uncertainty of the reaction rate constant for HO2 + HO2→H2O2 + O2 in our 3D-CTM KASIMA is discussed. We find best agreement between model and observations for applying rate constants according to Christensen et al. (2002 however, a mismatch in vertical profile shape remains. The observations were compared to the model results of KASIMA focusing on low to mid latitudes. Good agreement in spatial distribution and in temporal evolution was found. Highest vmr of H2O2 in the stratosphere were observed and modeled in low latitudes shortly after equinox at about 30 km. The modelled diurnal cycle with lowest vmr shortly after sunrise and highest vmr in the afternoon is confirmed by the MIPAS observations.

  14. Effects of global changes on the climatic niche of the tick Ixodes ricinus inferred by species distribution modelling

    Science.gov (United States)

    2013-01-01

    Background Global climate change can seriously impact on the epidemiological dynamics of vector-borne diseases. In this study we investigated how future climatic changes could affect the climatic niche of Ixodes ricinus (Acari, Ixodida), among the most important vectors of pathogens of medical and veterinary concern in Europe. Methods Species Distribution Modelling (SDM) was used to reconstruct the climatic niche of I. ricinus, and to project it into the future conditions for 2050 and 2080, under two scenarios: a continuous human demographic growth and a severe increase of gas emissions (scenario A2), and a scenario that proposes lower human demographic growth than A2, and a more sustainable gas emissions (scenario B2). Models were reconstructed using the algorithm of “maximum entropy”, as implemented in the software Maxent 3.3.3e; 4,544 occurrence points and 15 bioclimatic variables were used. Results In both scenarios an increase of climatic niche of about two times greater than the current area was predicted as well as a higher climatic suitability under the scenario B2 than A2. Such an increase occurred both in a latitudinal and longitudinal way, including northern Eurasian regions (e.g. Sweden and Russia), that were previously unsuitable for the species. Conclusions Our models are congruent with the predictions of range expansion already observed in I. ricinus at a regional scale and provide a qualitative and quantitative assessment of the future climatically suitable areas for I. ricinus at a continental scale. Although the use of SDM at a higher resolution should be integrated by a more refined analysis of further abiotic and biotic data, the results presented here suggest that under future climatic scenarios most of the current distribution area of I. ricinus could remain suitable and significantly increase at a continental geographic scale. Therefore disease outbreaks of pathogens transmitted by this tick species could emerge in previous non

  15. A revised molecular phylogeny of the globally distributed hawkmoth genus Hyles (Lepidoptera: Sphingidae), based on mitochondrial and nuclear DNA sequences.

    Science.gov (United States)

    Hundsdoerfer, Anna K; Rubinoff, Daniel; Attié, Marc; Wink, Michael; Kitching, Ian J

    2009-09-01

    The hawkmoth genus Hyles comprises some 29 species with a global distribution. In this study, we augment the previous taxon sampling with more species and add sequences from a nuclear gene to produce a refined phylogenetic hypothesis. A total evidence reconstruction based on Bayesian analysis of the combined mitochondrial (COI, t-RNA-Leu, COII; 2284 bp) and nuclear (EF1alpha; 773 bp) sequences is discussed and compared with the results from separate analyses of the two genes. The total evidence phylogeny corroborates many of the phylogenetic relationships previously postulated within the genus. In addition, the hitherto unsampled enigmatic species Hyles biguttata from Madagascar appears as sister group to Hyles livornicoides from Australia, although support for the relationship is relatively weak. The high level of differentiation of Hyles perkinsi from H. calida (both Hawaii), and the status of these two as sister species, is corroborated by both sources of sequence data. However, their phylogenetic position when mt DNA sequences alone are considered differs markedly from that under total evidence. The previously postulated relationships within the Hyles euphorbiae complex (HEC) s.s. are largely corroborated, but H. dahlii is now more closely related and the HEC s.l. is redefined to include H. zygophylli and H. stroehlei (two species that had not been studied previously using molecular data) and to exclude H. siehei and H. hippophaes. The nuclear sequences alone are insufficiently variable to fully resolve all lineages and the phylogeny suggests that nuclear gene swapping and incomplete lineage sorting have occurred implying recent divergence. The results from the total evidence analysis provide a phylogenetic hypothesis that both corroborates and complements the previous biogeographic scenario, and provides new insights into the origins of several of the included taxa.

  16. Influence of Last Glacial Maximum boundary conditions on the global water isotope distribution in an atmospheric general circulation model

    Directory of Open Access Journals (Sweden)

    T. Tharammal

    2013-03-01

    Full Text Available To understand the validity of δ18O proxy records as indicators of past temperature change, a series of experiments was conducted using an atmospheric general circulation model fitted with water isotope tracers (Community Atmosphere Model version 3.0, IsoCAM. A pre-industrial simulation was performed as the control experiment, as well as a simulation with all the boundary conditions set to Last Glacial Maximum (LGM values. Results from the pre-industrial and LGM simulations were compared to experiments in which the influence of individual boundary conditions (greenhouse gases, ice sheet albedo and topography, sea surface temperature (SST, and orbital parameters were changed each at a time to assess their individual impact. The experiments were designed in order to analyze the spatial variations of the oxygen isotopic composition of precipitation (δ18Oprecip in response to individual climate factors. The change in topography (due to the change in land ice cover played a significant role in reducing the surface temperature and δ18Oprecip over North America. Exposed shelf areas and the ice sheet albedo reduced the Northern Hemisphere surface temperature and δ18Oprecip further. A global mean cooling of 4.1 °C was simulated with combined LGM boundary conditions compared to the control simulation, which was in agreement with previous experiments using the fully coupled Community Climate System Model (CCSM3. Large reductions in δ18Oprecip over the LGM ice sheets were strongly linked to the temperature decrease over them. The SST and ice sheet topography changes were responsible for most of the changes in the climate and hence the δ18Oprecip distribution among the simulations.

  17. Expandable LED array interconnect

    Science.gov (United States)

    Yuan, Thomas Cheng-Hsin; Keller, Bernd

    2011-03-01

    A light emitting device that can function as an array element in an expandable array of such devices. The light emitting device comprises a substrate that has a top surface and a plurality of edges. Input and output terminals are mounted to the top surface of the substrate. Both terminals comprise a plurality of contact pads disposed proximate to the edges of the substrate, allowing for easy access to both terminals from multiple edges of the substrate. A lighting element is mounted to the top surface of the substrate. The lighting element is connected between the input and output terminals. The contact pads provide multiple access points to the terminals which allow for greater flexibility in design when the devices are used as array elements in an expandable array.

  18. Grazing incidence beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.

    1985-01-01

    A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

  19. Expanding the HAWC Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Johanna [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-17

    The High Altitude Water Cherenkov Gamma-Ray Observatory is expanding its current array of 300 water tanks to include 350 outrigger tanks to increase sensitivity to gamma rays above 10 TeV. This involves creating and testing hardware with which to build the new tanks, including photomultiplier tubes, high voltage supply units, and flash analog to digital converters. My responsibilities this summer included preparing, testing and calibrating that equipment.

  20. Hubble, Hubble's Law and the Expanding Universe

    Indian Academy of Sciences (India)

    Srimath

    H ubble's nam e is associated closely w ith the idea of an expanding universe as he discovered the relation between the recession velocity and the distances of galaxies. H ubble also did a lot of pioneering w ork on the distribution of galaxies in the universe. In this article we take a look at H ubble's law and discuss how it ...

  1. Expanding the concept of sustainable seafood using Life Cycle Assessment

    DEFF Research Database (Denmark)

    Ziegler, Friederike; Hornborg, Sara; Green, Bridget S

    2016-01-01

    Fisheries management and sustainability assessment of fisheries more generally have recently expanded their scope from single-species stock assessment to ecosystem-based approaches, aiming to incorporate economic, social and local environmental impacts, while still excluding global-scale environm......Fisheries management and sustainability assessment of fisheries more generally have recently expanded their scope from single-species stock assessment to ecosystem-based approaches, aiming to incorporate economic, social and local environmental impacts, while still excluding global...

  2. Large-scale upper tropospheric pollution observed by MIPAS HCN and C2H6 global distributions

    Directory of Open Access Journals (Sweden)

    A. Linden

    2009-12-01

    Full Text Available We present global upper tropospheric HCN and C2H6 amounts derived from MIPAS/ENVISAT limb emission spectra. HCN and C2H6 are retrieved in the spectral regions 715.5–782.7 cm−1 and 811.5–835.7 cm−1, respectively. The datasets consist of 54 days between September 2003 and March 2004. This period covers the peak and decline of the southern hemispheric biomass burning period and some months thereafter. HCN is a nearly unambiguous tracer of biomass burning with an assumed tropospheric lifetime of several months. Indeed, the most significant feature in the MIPAS HCN dataset is an upper tropospheric plume of enhanced values caused by southern hemispheric biomass burning, which in September and October 2003 extended from tropical South America over Africa, Australia to the Southern Pacific. The spatial extent of this plume agrees well with the MOPITT CO distribution of September 2003. Further there is good agreement with the shapes and mixing ratios of the southern hemispheric HCN and C2H6 fields measured by the ACE experiment between September and November 2005. The MIPAS HCN plume extended from the lowermost observation height of 8 km up to about 16 km altitude, with maximum values of 500–600 pptv in October 2003. It was still clearly visible in December 2003, but had strongly decreased by March 2004, confirming the assumed tropospheric lifetime. The main sources of C2H6 are production and transmission of fossil fuels, followed by biofuel use and biomass burning. The C2H6 distribution also clearly reflected the southern hemispheric biomass burning plume and its seasonal variation, with maximum amounts of 600–700 pptv. Generally there was good spatial overlap between the southern hemispheric distributions of both pollution tracers, except for the region between Peru and the mid-Pacific. Here C2H6was considerably enhanced, whereas the HCN amounts were low. Backward trajectory calculations suggested that industrial pollution was responsible

  3. Large-scale upper tropospheric pollution observed by MIPAS HCN and C2H6 global distributions

    Science.gov (United States)

    Glatthor, N.; von Clarmann, T.; Stiller, G. P.; Funke, B.; Koukouli, M. E.; Fischer, H.; Grabowski, U.; Höpfner, M.; Kellmann, S.; Linden, A.

    2009-12-01

    We present global upper tropospheric HCN and C2H6 amounts derived from MIPAS/ENVISAT limb emission spectra. HCN and C2H6 are retrieved in the spectral regions 715.5-782.7 cm-1 and 811.5-835.7 cm-1, respectively. The datasets consist of 54 days between September 2003 and March 2004. This period covers the peak and decline of the southern hemispheric biomass burning period and some months thereafter. HCN is a nearly unambiguous tracer of biomass burning with an assumed tropospheric lifetime of several months. Indeed, the most significant feature in the MIPAS HCN dataset is an upper tropospheric plume of enhanced values caused by southern hemispheric biomass burning, which in September and October 2003 extended from tropical South America over Africa, Australia to the Southern Pacific. The spatial extent of this plume agrees well with the MOPITT CO distribution of September 2003. Further there is good agreement with the shapes and mixing ratios of the southern hemispheric HCN and C2H6 fields measured by the ACE experiment between September and November 2005. The MIPAS HCN plume extended from the lowermost observation height of 8 km up to about 16 km altitude, with maximum values of 500-600 pptv in October 2003. It was still clearly visible in December 2003, but had strongly decreased by March 2004, confirming the assumed tropospheric lifetime. The main sources of C2H6 are production and transmission of fossil fuels, followed by biofuel use and biomass burning. The C2H6 distribution also clearly reflected the southern hemispheric biomass burning plume and its seasonal variation, with maximum amounts of 600-700 pptv. Generally there was good spatial overlap between the southern hemispheric distributions of both pollution tracers, except for the region between Peru and the mid-Pacific. Here C2H6was considerably enhanced, whereas the HCN amounts were low. Backward trajectory calculations suggested that industrial pollution was responsible for the elevated C2H6

  4. The expanding universe

    CERN Document Server

    Lew, Kristi

    2011-01-01

    People have always been fascinated with the stars above and the universe that contains them. Over the years, astronomers have developed numerous theories to explain how the universe began, how it works, and what its ultimate fate will be. But all of the scientists' questions are far from answered. The Expanding Universe goes beyond the creation of the universe to explain how scientists think the universe works, grows, and changes, including what great thinkers Isaac Newton and Albert Einstein had to say about its fate. Readers will also learn about how researchers are slowly shedding light on

  5. Expanding Your Horizon 2015

    CERN Multimedia

    Kaltenhauser, Kristin

    2015-01-01

    Expanding your horizons is a bi-annual “Science Day” for girls aged 11 to 14, held at the University of Geneva on 14 November. The girls had the opportunity to take part in hands-on workshops held by local professional women in the field of science, mathematics, engineering and technology. For the fourth time, CERN was part of this event, offering three workshops as well as a booth at the Discovery Fair, including Higgnite, an interactive visualization of the Higgs Field.

  6. Evaluation of near-tropopause ozone distributions in the Global Modeling Initiative combined stratosphere/troposphere model with ozonesonde data

    Directory of Open Access Journals (Sweden)

    D. B. Considine

    2008-05-01

    Full Text Available The NASA Global Modeling Initiative has developed a combined stratosphere/troposphere chemistry and transport model which fully represents the processes governing atmospheric composition near the tropopause. We evaluate model ozone distributions near the tropopause, using two high vertical resolution monthly mean ozone profile climatologies constructed with ozonesonde data, one by averaging on pressure levels and the other relative to the thermal tropopause. At the tropopause, model ozone is high-biased in the SH tropics and NH midlatitudes by ~45% in a 4° latitude ×5° longitude model simulation. Doubling the resolution to 2°×2.5° increases the NH high bias to ~60%, and reduces the tropical bias to ~30%, apparently due to decreased horizontal transport between the tropics and extratropics in the higher-resolution simulation. These ozone biases do not appear to be due to an overly vigorous residual circulation, insufficient convection, or excessive stratosphere/troposphere exchange, and so may be due to insufficient vertical resolution or excessive vertical diffusion near the tropopause. In the upper troposphere and lower stratosphere, model/measurement intercomparisons are strongly affected by the averaging technique.

    Compared to the pressure-averaged climatology, NH and tropical mean model lower stratospheric biases are >20%. In the upper troposphere, the 2°×2.5° simulation shows mean high biases of ~20% and ~35% during April in the tropics and NH midlatitudes, respectively. This apparently good model/measurement agreement degrades when relative-to-tropopause averages are considered, with upper troposphere high biases of ~30% and 70% in the tropics and NH midlatitudes. This occurs because relative-to-tropopause averaging better preserves the larger cross-tropopause O3 gradients which are seen in the daily sonde data, but not in daily model profiles. Relative-to-tropopause averages therefore more accurately reveal

  7. Evaluation of Near-Tropopause Ozone Distributions in the Global Modeling Initiative Combined Stratosphere/Troposphere Model with Ozonesonde Data

    Science.gov (United States)

    Considine, David B.; Logan, Jennifer A.; Olsen, Mark A.

    2008-01-01

    The NASA Global Modeling Initiative has developed a combined stratosphere/troposphere chemistry and transport model which fully represents the processes governing atmospheric composition near the tropopause. We evaluate model ozone distributions near the tropopause, using two high vertical resolution monthly mean ozone profile climatologies constructed with ozonesonde data, one by averaging on pressure levels and the other relative to the thermal tropopause. Model ozone is high biased at the SH tropical and NH midlatitude tropopause by approx. 45% in a 4 deg. latitude x 5 deg. longitude model simulation. Increasing the resolution to 2 deg. x 2.5 deg. increases the NH tropopause high bias to approx. 60%, but decreases the tropical tropopause bias to approx. 30%, an effect of a better-resolved residual circulation. The tropopause ozone biases appear not to be due to an overly vigorous residual circulation or excessive stratosphere/troposphere exchange, but are more likely due to insufficient vertical resolution or excessive vertical diffusion near the tropopause. In the upper troposphere and lower stratosphere, model/measurement intercomparisons are strongly affected by the averaging technique. NH and tropical mean model lower stratospheric biases are less than 20%. In the upper troposphere, the 2 deg. x 2.5 deg. simulation exhibits mean high biases of approx. 20% and approx. 35% during April in the tropics and NH midlatitudes, respectively, compared to the pressure averaged climatology. However, relative-to-tropopause averaging produces upper troposphere high biases of approx. 30% and 70% in the tropics and NH midlatitudes. This is because relative-to-tropopause averaging better preserves large cross-tropopause O3 gradients, which are seen in the daily sonde data, but not in daily model profiles. The relative annual cycle of ozone near the tropopause is reproduced very well in the model Northern Hemisphere midlatitudes. In the tropics, the model amplitude of the

  8. Simulation of particle size distribution with a global aerosol model: contribution of nucleation to aerosol and CCN number concentrations

    Directory of Open Access Journals (Sweden)

    F. Yu

    2009-10-01

    Full Text Available An advanced particle microphysics model with a number of computationally efficient schemes has been incorporated into a global chemistry transport model (GEOS-Chem to simulate particle number size distributions and cloud condensation nuclei (CCN concentrations in the atmosphere. Size-resolved microphysics for secondary particles (i.e., those formed from gaseous species and sea salt has been treated in the present study. The growth of nucleated particles through the condensation of sulfuric acid vapor and equilibrium uptake of nitrate, ammonium, and secondary organic aerosol is explicitly simulated, along with the scavenging of secondary particles by primary particles (dust, black carbon, organic carbon, and sea salt. We calculate secondary particle formation rate based on ion-mediated nucleation (IMN mechanism and constrain the parameterizations of primary particle emissions with various observations. Our simulations indicate that secondary particles formed via IMN appear to be able to account for the particle number concentrations observed in many parts of the troposphere. A comparison of the simulated annual mean concentrations of condensation nuclei larger than 10 nm (CN10 with those measured values show very good agreement (within a factor of two in near all 22 sites around the globe that have at least one full year of CN10 measurements. Secondary particles appear to dominate the number abundance in most parts of the troposphere. Calculated CCN concentration at supersaturation of 0.4% (CCN0.4 and the fraction of CCN0.4 that is secondary (fsecCCN have large spatial variations. Over the middle latitude in the Northern Hemisphere, zonally averaged CCN0.4 decreases from ~400–700 cm−3 in the boundary layer (BL to below 100 cm−3 above altitude of ~4 km, the corresponding fsecCCN values change from 50–60% to above ~70%. In the Southern Hemisphere, the zonally

  9. Existence and Globally Asymptotic Stability of Equilibrium Solution for Fractional-Order Hybrid BAM Neural Networks with Distributed Delays and Impulses

    Directory of Open Access Journals (Sweden)

    Hai Zhang

    2017-01-01

    Full Text Available This paper investigates the existence and globally asymptotic stability of equilibrium solution for Riemann-Liouville fractional-order hybrid BAM neural networks with distributed delays and impulses. The factors of such network systems including the distributed delays, impulsive effects, and two different fractional-order derivatives between the U-layer and V-layer are taken into account synchronously. Based on the contraction mapping principle, the sufficient conditions are derived to ensure the existence and uniqueness of the equilibrium solution for such network systems. By constructing a novel Lyapunov functional composed of fractional integral and definite integral terms, the globally asymptotic stability criteria of the equilibrium solution are obtained, which are dependent on the order of fractional derivative and network parameters. The advantage of our constructed method is that one may directly calculate integer-order derivative of the Lyapunov functional. A numerical example is also presented to show the validity and feasibility of the theoretical results.

  10. Global usability

    CERN Document Server

    Douglas, Ian

    2011-01-01

    The concept of usability has become an increasingly important consideration in the design of all kinds of technology. As more products are aimed at global markets and developed through internationally distributed teams, usability design needs to be addressed in global terms. Interest in usability as a design issue and specialist area of research and education has developed steadily in North America and Europe since the 1980's. However, it is only over the last ten years that it has emerged as a global concern. Global Usability provides an introduction to the important issues in globalizing des

  11. A Global Model of Predicted Peregrine Falcon (Falco peregrinus) Distribution with Open Source GIS Code and 104 Open Access Layers for use by the global public

    OpenAIRE

    Sriram, Sumithra; Huettmann, Falk

    2017-01-01

    Peregrine falcons (Falco peregrinus) are among the fastest members of the animal kingdom, and they are probably the most widely distributed raptors in the world; their migrations and habitats range from the tundra, mountains and some deserts to the tropics, coastal zones and urban habitats. Habitat loss, conversion, contamination, pesticides and other anthropogenic pressures are all known factors that have an adverse effect on these species. However, while peregrine falcons were removed from ...

  12. Applicability of global public domain data versus local detailed data for distributed hydrological modelling: a study form Gin river basin Sri Lanka

    Science.gov (United States)

    Wickramaarachchi, T. N.; Ishidaira, H.; Wijayaratna, T. M. N.

    2013-06-01

    This study investigates the applicability of global public domain data versus local detailed data for distributed hydrological modelling using a case study approach. Major hydrological characteristics in Gin river basin are simulated in the study by applying the distributed hydrological model, YHyM/BTOPMC (University of Yamanashi Distributed Hydrological Model with Block-wise use of TOPMODEL and Muskingum-Cunge method) utilizing the global public domain data sets (Case 1) and local detailed data sets (Case 2). Evaluation of the model outputs for Case 1 and Case 2 shows that the overall hydrological behavior of the Gin river basin is adequately simulated by the model for both Case 1 and Case 2. The simulated average annual discharge volumes in Case 1 and Case 2 at Agaliya during 2002-2006, vary from the observed average annual discharge volume by +4.25 and +1.31 %, respectively. In general, simulated daily discharge in Case 1 shows slightly higher value than that of Case 2 resulting a difference of 0.9 m3/s during 2002-2006, on average. The relative differences between the simulated daily discharges in Case 1 and Case 2 become higher during the recession limbs of the flow hydrographs at Agaliya. Reasons for these variations are being discussed in the study. The results of the study give motivation towards the use of global public domain data for hydrologic simulations in data-poor (limited availability of local data) basins.

  13. Tracking the Global Distribution of Persistent Organic Pollutants Accounting for E-Waste Exports to Developing Regions.

    Science.gov (United States)

    Breivik, Knut; Armitage, James M; Wania, Frank; Sweetman, Andrew J; Jones, Kevin C

    2016-01-19

    Elevated concentrations of various industrial-use Persistent Organic Pollutants (POPs), such as polychlorinated biphenyls (PCBs), have been reported in some developing areas in subtropical and tropical regions known to be destinations of e-waste. We used a recent inventory of the global generation and exports of e-waste to develop various global scale emission scenarios for industrial-use organic contaminants (IUOCs). For representative IUOCs (RIUOCs), only hypothetical emissions via passive volatilization from e-waste were considered whereas for PCBs, historical emissions throughout the chemical life-cycle (i.e., manufacturing, use, disposal) were included. The environmental transport and fate of RIUOCs and PCBs were then simulated using the BETR Global 2.0 model. Export of e-waste is expected to increase and sustain global emissions beyond the baseline scenario, which assumes no export. A comparison between model predictions and observations for PCBs in selected recipient regions generally suggests a better agreement when exports are accounted for. This study may be the first to integrate the global transport of IUOCs in waste with their long-range transport in air and water. The results call for integrated chemical management strategies on a global scale.

  14. The asymmetric impact of global warming on US drought types and distributions in a large ensemble of 97 hydro-climatic simulations.

    Science.gov (United States)

    Huang, Shengzhi; Leng, Guoyong; Huang, Qiang; Xie, Yangyang; Liu, Saiyan; Meng, Erhao; Li, Pei

    2017-07-19

    Projection of future drought is often involved large uncertainties from climate models, emission scenarios as well as drought definitions. In this study, we investigate changes in future droughts in the conterminous United States based on 97 1/8 degree hydro-climate model projections. Instead of focusing on a specific drought type, we investigate changes in meteorological, agricultural, and hydrological drought as well as the concurrences. Agricultural and hydrological droughts are projected to become more frequent with increase in global mean temperature, while less meteorological drought is expected. Changes in drought intensity scale linearly with global temperature rises under RCP8.5 scenario, indicating the potential feasibility to derive future drought severity given certain global warming amount under this scenario. Changing pattern of concurrent droughts generally follows that of agricultural and hydrological droughts. Under the 1.5 °C warming target as advocated in recent Paris agreement, several hot spot regions experiencing highest droughts are identified. Extreme droughts show similar patterns but with much larger magnitude than the climatology. This study highlights the distinct response of droughts of various types to global warming and the asymmetric impact of global warming on drought distribution resulting in a much stronger influence on extreme drought than on mean drought.

  15. Expanding hollow metal rings

    Science.gov (United States)

    Peacock, Harold B [Evans, GA; Imrich, Kenneth J [Grovetown, GA

    2009-03-17

    A sealing device that may expand more planar dimensions due to internal thermal expansion of a filler material. The sealing material is of a composition such that when desired environment temperatures and internal actuating pressures are reached, the sealing materials undergoes a permanent deformation. For metallic compounds, this permanent deformation occurs when the material enters the plastic deformation phase. Polymers, and other materials, may be using a sealing mechanism depending on the temperatures and corrosivity of the use. Internal pressures are generated by either rapid thermal expansion or material phase change and may include either liquid or solid to gas phase change, or in the gaseous state with significant pressure generation in accordance with the gas laws. Sealing material thickness and material composition may be used to selectively control geometric expansion of the seal such that expansion is limited to a specific facing and or geometric plane.

  16. Atmospheric mercury concentrations observed at ground-based monitoring sites globally distributed in the framework of the GMOS network

    Science.gov (United States)

    Sprovieri, Francesca; Pirrone, Nicola; Bencardino, Mariantonia; D'Amore, Francesco; Carbone, Francesco; Cinnirella, Sergio; Mannarino, Valentino; Landis, Matthew; Ebinghaus, Ralf; Weigelt, Andreas; Brunke, Ernst-Günther; Labuschagne, Casper; Martin, Lynwill; Munthe, John; Wängberg, Ingvar; Artaxo, Paulo; Morais, Fernando; Barbosa, Henrique de Melo Jorge; Brito, Joel; Cairns, Warren; Barbante, Carlo; Diéguez, María del Carmen; Garcia, Patricia Elizabeth; Dommergue, Aurélien; Angot, Helene; Magand, Olivier; Skov, Henrik; Horvat, Milena; Kotnik, Jože; Read, Katie Alana; Mendes Neves, Luis; Gawlik, Bernd Manfred; Sena, Fabrizio; Mashyanov, Nikolay; Obolkin, Vladimir; Wip, Dennis; Feng, Xin Bin; Zhang, Hui; Fu, Xuewu; Ramachandran, Ramesh; Cossa, Daniel; Knoery, Joël; Marusczak, Nicolas; Nerentorp, Michelle; Norstrom, Claus

    2016-09-01

    Long-term monitoring of data of ambient mercury (Hg) on a global scale to assess its emission, transport, atmospheric chemistry, and deposition processes is vital to understanding the impact of Hg pollution on the environment. The Global Mercury Observation System (GMOS) project was funded by the European Commission (gmos.eu" target="_blank">http://www.gmos.eu) and started in November 2010 with the overall goal to develop a coordinated global observing system to monitor Hg on a global scale, including a large network of ground-based monitoring stations, ad hoc periodic oceanographic cruises and measurement flights in the lower and upper troposphere as well as in the lower stratosphere. To date, more than 40 ground-based monitoring sites constitute the global network covering many regions where little to no observational data were available before GMOS. This work presents atmospheric Hg concentrations recorded worldwide in the framework of the GMOS project (2010-2015), analyzing Hg measurement results in terms of temporal trends, seasonality and comparability within the network. Major findings highlighted in this paper include a clear gradient of Hg concentrations between the Northern and Southern hemispheres, confirming that the gradient observed is mostly driven by local and regional sources, which can be anthropogenic, natural or a combination of both.

  17. Flat-topped mountain ranges: Their global distribution and value for understanding the evolution of mountain topography

    Science.gov (United States)

    Calvet, Marc; Gunnell, Yanni; Farines, Bernard

    2015-07-01

    Extensive tracts of low-gradient topography in steep mountain ranges, either forming rangetop plateaus or terraced pediments on range flanks, are widely distributed in mountain belts around the world. Before the advent of plate tectonics, such populations of planar landforms were interpreted as vestiges of a post-orogenic raised peneplain, i.e., a low-gradient land surface resulting from the decay, during long intervals of base-level stability, of a previous mountain range that was subsequently raised once again to great elevations-thus forming a new mountain range. This two-stage model has been challenged by theories that advocate continuity in tectonic processes and more gradual changes in base level, and thus expect a more immediate and proportionate response of geomorphic systems. Here we present a global survey of erosion surfaces in mountain ranges and put existing theories and empirical evidence into a broad perspective calling for further research into the rates and regimes of long-term mountain evolution. The resulting library of case studies provides opportunities for comparative analysis and helps to classify the landform mosaics that are likely to arise from the interplay between (i) crustal regimes, which at convergent plate margins need be neither uniform nor steady at all times; (ii) radiation-driven and gravity-driven geomorphic regimes, which are mainly determined by crustal boundary conditions and climate; and (iii) paleogeography, through which clues about base-level changes can be obtained. We examine intracratonic and plate-margin settings, with examples from thin-skinned fold belts, thick-skinned fold belts, island-arc and other subduction-related settings, and bivergent collisional orogens. Results reveal that the existence of erosion surfaces is not a simple function of geodynamic setting. Although some erosion surfaces are pre-orogenic, evidence about their predominantly post-orogenic age is supported by apatite fission-track and helium

  18. Expanding the population coverage of evidence-based interventions with community health workers to save the lives of mothers and children: an analysis of potential global impact using the Lives Saved Tool (LiST).

    Science.gov (United States)

    Chou, Victoria B; Friberg, Ingrid K; Christian, Mervyn; Walker, Neff; Perry, Henry B

    2017-12-01

    Evidence has been accumulating that community health workers (CHWs) providing evidence-based interventions as part of community-based primary health care (CBPHC) can lead to reductions in maternal, neonatal and child mortality. However, investments to strengthen and scale-up CHW programs still remain modest. We used the Lives Saved Tool (LiST) to estimate the number of maternal, neonatal and child deaths and stillbirths that could be prevented if 73 countries effectively scaled up the population coverage of 30 evidence-based interventions that CHWs can deliver in these high-burden countries. We set population coverage targets at 50%, 70%, and 90% and summed the country-level results by region and by all 73 high-burden countries combined. We also estimated which specific interventions would save the most lives. LiST estimates that a total of 3.0 (sensitivity bounds 1.8-4.0), 4.9 (3.1-6.3) and 6.9 (3.7-8.7) million deaths would be prevented between 2016 and 2020 if CBPHC is gradually scaled up during this period and if coverage of key interventions reaches 50%, 70%, and 90% respectively. There would be 14%, 23%, and 32% fewer deaths in the final year compared to a scenario assuming no intervention coverage scale up. The Africa Region would receive the most benefit by far: 58% of the lives saved at 90% coverage would be in this region. The interventions contributing the greatest impact are nutritional interventions during pregnancy, treatment of malaria with artemisinin compounds, oral rehydration solution for childhood diarrhea, hand washing with soap, and oral antibiotics for pneumonia. Scaling up CHW programming to increase population-level coverage of life-saving interventions represents a very promising strategy to achieve universal health coverage and end preventable maternal and child deaths by 2030. Numerous practical challenges must be overcome, but there is no better alternative at present. Expanding the coverage of key interventions for maternal nutrition

  19. A theory of local and global processes which affect solar wind electrons. I - The origin of typical 1 AU velocity distribution functions - Steady state theory

    Science.gov (United States)

    Scudder, J. D.; Olbert, S.

    1979-01-01

    A kinetic theory for the velocity distribution of solar wind electrons which illustrates the global and local properties of the solar wind expansion is proposed. By means of the Boltzmann equation with the Krook collision operator accounting for Coulomb collisions, it is found that Coulomb collisions determine the population and shape of the electron distribution function in both the thermal and suprathermal energy regimes. For suprathermal electrons, the cumulative effects of Coulomb interactions are shown to take place on the scale of the heliosphere itself, whereas the Coulomb interactions of thermal electrons occur on a local scale near the point of observation (1 AU). The bifurcation of the electron distribution between thermal and suprathermal electrons is localized to the deep solar corona (1 to 10 solar radii).

  20. Influence of explicit Phaeocystis parameterizations on the global distribution of marine dimethyl sulfide: Explicit Phaeocystis in a DMS Model

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shanlin [Climate Ocean and Sea Ice Modeling Group, Los Alamos National Laboratory, Los Alamos New Mexico USA; Elliott, Scott [Climate Ocean and Sea Ice Modeling Group, Los Alamos National Laboratory, Los Alamos New Mexico USA; Maltrud, Mathew [Climate Ocean and Sea Ice Modeling Group, Los Alamos National Laboratory, Los Alamos New Mexico USA; Cameron-Smith, Philip [Atmospheric, Earth, and Energy Division, Lawrence Livermore National Laboratory, Livermore California USA

    2015-11-01

    Dimethyl sulfide (DMS) is a biogenic organosulfur compound which contributes strongly to marine aerosol mass and the determination of cloud condensation nuclei over the remote oceans. Since uncertainties in DMS flux to the atmosphere lead to large variations in climate forcing, the global DMS distribution has been the subject of increasingly complex dynamic simulations. DMS concentrations are directly controlled by marine ecosystems. Phaeocystis is a major DMS producer but is often omitted from global reduced sulfur mechanisms. Here we incorporate this phytoplankton group into the marine ecosystem-biogeochemical module of the Community Earth System Model. To examine its role in the ocean sulfur cycle, an earlier DMS model has been enhanced to include new knowledge gained over the last few years. Results from the baseline run show that simulated Phaeocystis biomass generally agrees with observations, with high concentrations near the Antarctic continent and between 50° and 60° north. Given the new explicit Phaeocystis representation, the DMS distribution shows significant improvements, especially regarding the amplitude and location of high-latitude peaks. The simulated global mean surface DMS value is 2.26 nM, comparable to an estimate of 2.34 nM from the latest climatology extrapolated based on observations. The total oceanic DMS source to the atmosphere is 20.4 Tg S/yr, on the low side of previous estimates. Comparisons with and without Phaeocystis show that the group dominates DMS distributions in temperate and cold waters, contributing 13% of the global flux. The proportion may increase as sea ice declines and should be considered in climate projections.