Science.gov

Sample records for ligand-induced global transitions

  1. Ligand-induced global transitions in the catalytic domain of protein kinase A

    PubMed Central

    Hyeon, Changbong; Jennings, Patricia A.; Adams, Joseph A.; Onuchic, José N.

    2009-01-01

    Conformational transitions play a central role in the phosphorylation mechanisms of protein kinase. To understand the nature of these transitions, we investigated the dynamics of nucleotide binding to the catalytic domain of PKA, a prototype for the protein kinase enzyme family. The open-to-closed transition in PKA was constructed as a function of ATP association by using available X-ray data and Brownian dynamics. Analyzing the multiple kinetic trajectories at the residue level, we find that the spatial rearrangement of the residues around the nucleotide-binding pocket, along with suppressed local fluctuations, controls the compaction of the entire molecule. In addition, to accommodate the stresses induced by ATP binding at the early transition stage, partial unfoldings (cracking) and reformations of several native contacts occur at the interfaces between the secondary structure motifs enveloping the binding pocket. This suggests that the enzyme experiences local structural deformations while reaching its functional, ATP-bound state. Our dynamical view of the ligand-induced transitions in PKA suggests that the kinetic hierarchy of local and global dynamics, the variable fluctuation of residues and the necessity of partial local unfolding may be fundamental components in other large scale allosteric transitions. PMID:19204278

  2. Local and global ligand-induced changes in the structure of the GABA(A) receptor.

    PubMed

    Muroi, Yukiko; Czajkowski, Cynthia; Jackson, Meyer B

    2006-06-13

    Ligand-gated channels mediate synaptic transmission through conformational transitions triggered by the binding of neurotransmitters. These transitions are well-defined in terms of ion conductance, but their structural basis is poorly understood. To probe these changes in structure, GABA(A) receptors were expressed in Xenopus oocytes and labeled at selected sites with environment-sensitive fluorophores. With labels at two different residues in the alpha1 subunit in loop E of the GABA-binding pocket, GABA elicited fluorescence changes opposite in sign. This pattern of fluorescence changes is consistent with a closure of the GABA-binding cavity at the subunit interface. The competitive antagonist SR-95531 inverted this pattern of fluorescence change, but the noncompetitive antagonist picrotoxin failed to elicit optical signals. In response to GABA (but not SR-95531), labels at the homologous residues in the beta2 subunit showed the same pattern of fluorescence change as the alpha1-subunit labels, indicating a global transition with comparable movements in homologous regions of different subunits. Incorporation of the gamma2 subunit altered the fluorescence changes of alpha1-subunit labels and eliminated them in beta2-subunit labels. Thus, the ligand-induced structural changes in the GABA(A) receptor can extend over considerable distances or remain highly localized, depending upon subunit composition and ligand.

  3. Minimum free energy path of ligand-induced transition in adenylate kinase.

    PubMed

    Matsunaga, Yasuhiro; Fujisaki, Hiroshi; Terada, Tohru; Furuta, Tadaomi; Moritsugu, Kei; Kidera, Akinori

    2012-01-01

    Large-scale conformational changes in proteins involve barrier-crossing transitions on the complex free energy surfaces of high-dimensional space. Such rare events cannot be efficiently captured by conventional molecular dynamics simulations. Here we show that, by combining the on-the-fly string method and the multi-state Bennett acceptance ratio (MBAR) method, the free energy profile of a conformational transition pathway in Escherichia coli adenylate kinase can be characterized in a high-dimensional space. The minimum free energy paths of the conformational transitions in adenylate kinase were explored by the on-the-fly string method in 20-dimensional space spanned by the 20 largest-amplitude principal modes, and the free energy and various kinds of average physical quantities along the pathways were successfully evaluated by the MBAR method. The influence of ligand binding on the pathways was characterized in terms of rigid-body motions of the lid-shaped ATP-binding domain (LID) and the AMP-binding (AMPbd) domains. It was found that the LID domain was able to partially close without the ligand, while the closure of the AMPbd domain required the ligand binding. The transition state ensemble of the ligand bound form was identified as those structures characterized by highly specific binding of the ligand to the AMPbd domain, and was validated by unrestrained MD simulations. It was also found that complete closure of the LID domain required the dehydration of solvents around the P-loop. These findings suggest that the interplay of the two different types of domain motion is an essential feature in the conformational transition of the enzyme.

  4. GLOBAL TRANSITION TO SUSTAINABLE DEVELOPMENT

    EPA Science Inventory

    Global transition to sustainable development is possible but many obstacles lie in the way and it will require acts of political will on the part of both the developed and developing nations to become a reality. In this paper, sustainable development is defined as continuous prog...

  5. GLOBAL TRANSITION TO SUSTAINABLE DEVELOPMENT

    EPA Science Inventory

    Environmental accounting using emergy is a tool for evaluating development and determining what is sustainable. Global sustainable development means that all nations will become better places for their inhabitants to live. Development follows a cycle of change from rapid growth ...

  6. Potential global jamming transition in aviation networks

    NASA Astrophysics Data System (ADS)

    Ezaki, Takahiro; Nishinari, Katsuhiro

    2014-08-01

    In this paper, we propose a nonlinear transport model for an aviation network. The takeoff rate from an airport is characterized by the degree of ground congestion. Due to the effect of surface congestion, the performance of an airport deteriorates because of inefficient configurations of waiting aircraft on the ground. Using a simple transport model, we performed simulations on a United States airport network and found a global jamming transition induced by local surface congestion. From a physical perspective, the mechanism of the transition is studied analytically and the resulting aircraft distribution is discussed considering system dynamics. This study shows that the knowledge of the relationship between a takeoff rate and a congestion level on the ground is vital for efficient air traffic operations.

  7. Potential global jamming transition in aviation networks.

    PubMed

    Ezaki, Takahiro; Nishinari, Katsuhiro

    2014-08-01

    In this paper, we propose a nonlinear transport model for an aviation network. The takeoff rate from an airport is characterized by the degree of ground congestion. Due to the effect of surface congestion, the performance of an airport deteriorates because of inefficient configurations of waiting aircraft on the ground. Using a simple transport model, we performed simulations on a United States airport network and found a global jamming transition induced by local surface congestion. From a physical perspective, the mechanism of the transition is studied analytically and the resulting aircraft distribution is discussed considering system dynamics. This study shows that the knowledge of the relationship between a takeoff rate and a congestion level on the ground is vital for efficient air traffic operations.

  8. Ligand-induced conformational changes in a thermophilic ribose-binding protein

    SciTech Connect

    Cuneo, Matthew J.; Beese, Lorena S.; Hellinga, Homme W.

    2009-05-21

    Members of the periplasmic binding protein (PBP) superfamily are involved in transport and signaling processes in both prokaryotes and eukaryotes. Biological responses are typically mediated by ligand-induced conformational changes in which the binding event is coupled to a hinge-bending motion that brings together two domains in a closed form. In all PBP-mediated biological processes, downstream partners recognize the closed form of the protein. This motion has also been exploited in protein engineering experiments to construct biosensors that transduce ligand binding to a variety of physical signals. Understanding the mechanistic details of PBP conformational changes, both global (hinge bending, twisting, shear movements) and local (rotamer changes, backbone motion), therefore is not only important for understanding their biological function but also for protein engineering experiments. Here we present biochemical characterization and crystal structure determination of the periplasmic ribose-binding protein (RBP) from the hyperthermophile Thermotoga maritima in its ribose-bound and unliganded state. The T. maritima RBP (tmRBP) has 39% sequence identity and is considerably more resistant to thermal denaturation (appTm value is 108 C) than the mesophilic Escherichia coli homolog (ecRBP) (appTm value is 56 C). Polar ligand interactions and ligand-induced global conformational changes are conserved among ecRBP and tmRBP; however local structural rearrangements involving side-chain motions in the ligand-binding site are not conserved. Although the large-scale ligand-induced changes are mediated through similar regions, and are produced by similar backbone movements in tmRBP and ecRBP, the small-scale ligand-induced structural rearrangements differentiate the mesophile and thermophile. This suggests there are mechanistic differences in the manner by which these two proteins bind their ligands and are an example of how two structurally similar proteins utilize different

  9. Global quantum discord and quantum phase transition in XY model

    SciTech Connect

    Liu, Si-Yuan; Zhang, Yu-Ran; Yang, Wen-Li; Fan, Heng

    2015-11-15

    We study the relationship between the behavior of global quantum correlations and quantum phase transitions in XY model. We find that the two kinds of phase transitions in the studied model can be characterized by the features of global quantum discord (GQD) and the corresponding quantum correlations. We demonstrate that the maximum of the sum of all the nearest neighbor bipartite GQDs is effective and accurate for signaling the Ising quantum phase transition, in contrast, the sudden change of GQD is very suitable for characterizing another phase transition in the XY model. This may shed lights on the study of properties of quantum correlations in different quantum phases.

  10. Biotic transitions in global marine diversity

    NASA Technical Reports Server (NTRS)

    Miller, A. I.

    1998-01-01

    Long-term transitions in the composition of Earth's marine biota during the Phanerozoic have historically been explained in two different ways. One view is that they were mediated through biotic interactions among organisms played out over geologic time. The other is that mass extinctions transcended any such interactions and governed diversity over the long term by resetting the relative diversities of higher taxa. However, a growing body of evidence suggests that macroevolutionary processes effecting biotic transitions during background times were not fundamentally different from those operating during mass extinctions. Physical perturbations at many geographic scales combined to produce the long-term trajectory of Phanerozoic diversity.

  11. Forest transitions, trade, and the global displacement of land use.

    PubMed

    Meyfroidt, Patrick; Rudel, Thomas K; Lambin, Eric F

    2010-12-07

    Reducing tropical deforestation is an international priority, given its impacts on carbon emissions and biodiversity. We examined whether recent forest transitions--a shift from net deforestation to net reforestation--involved a geographic displacement of forest clearing across countries through trade in agricultural and forest products. In most of the seven developing countries that recently experienced a forest transition, displacement of land use abroad accompanied local reforestation. Additional global land-use change embodied in their net wood trade offset 74% of their total reforested area. Because the reforesting countries continued to export more agricultural goods than they imported, this net displacement offset 22% of their total reforested area when both agriculture and forestry sectors are included. However, this net displacement increased to 52% during the last 5 y. These countries thus have contributed to a net global reforestation and/or decrease in the pressure on forests, but this global environmental benefit has been shrinking during recent years. The net decrease in the pressure on forests does not account for differences in their ecological quality. Assessments of the impacts of international policies aimed at reducing global deforestation should integrate international trade in agricultural and forest commodities.

  12. Forest transitions, trade, and the global displacement of land use

    PubMed Central

    Meyfroidt, Patrick; Rudel, Thomas K.; Lambin, Eric F.

    2010-01-01

    Reducing tropical deforestation is an international priority, given its impacts on carbon emissions and biodiversity. We examined whether recent forest transitions—a shift from net deforestation to net reforestation—involved a geographic displacement of forest clearing across countries through trade in agricultural and forest products. In most of the seven developing countries that recently experienced a forest transition, displacement of land use abroad accompanied local reforestation. Additional global land-use change embodied in their net wood trade offset 74% of their total reforested area. Because the reforesting countries continued to export more agricultural goods than they imported, this net displacement offset 22% of their total reforested area when both agriculture and forestry sectors are included. However, this net displacement increased to 52% during the last 5 y. These countries thus have contributed to a net global reforestation and/or decrease in the pressure on forests, but this global environmental benefit has been shrinking during recent years. The net decrease in the pressure on forests does not account for differences in their ecological quality. Assessments of the impacts of international policies aimed at reducing global deforestation should integrate international trade in agricultural and forest commodities. PMID:21078977

  13. Discontinuous transitions in globally coupled potential systems with additive noise

    NASA Astrophysics Data System (ADS)

    Kürsten, Rüdiger; Behn, Ulrich

    2016-12-01

    An infinite array of globally coupled overdamped constituents moving in a double-well potential with n th order saturation term under the influence of additive Gaussian white noise is investigated. The system exhibits a continuous phase transition from a symmetric phase to a symmetry-broken phase. The qualitative behavior is independent on n . The critical point is calculated for strong and for weak noise; these limits are also bounds for the critical point. Introducing an additional nonlinearity, such that the potential can have up to three minima, leads to richer behavior. There the parameter space divides into three regions: a region with a symmetric phase, a region with a phase of broken symmetry and a region where both phases coexist. The region of coexistence collapses into one of the others via a discontinuous phase transition, whereas the transition between the symmetric phase and the phase of broken symmetry is continuous. The tricritical point where the three regions intersect can be calculated for strong and for weak noise. These limiting values form tight bounds on the tricritical point. In the region of coexistence simulations of finite systems are performed. One finds that the stationary distribution of finite but large systems differs qualitatively from the one of the infinite system. Hence the limits of stationarity and large system size do not commute.

  14. The epidemiological transition and the global childhood obesity epidemic

    PubMed Central

    Broyles, S T; Denstel, K D; Church, T S; Chaput, J-P; Fogelholm, M; Hu, G; Kuriyan, R; Kurpad, A; Lambert, E V; Maher, C; Maia, J; Matsudo, V; Olds, T; Onywera, V; Sarmiento, O L; Standage, M; Tremblay, M S; Tudor-Locke, C; Zhao, P; Katzmarzyk, P T

    2015-01-01

    OBJECTIVES: Childhood obesity is now recognized as a global public health issue. Social patterning of obesity, consistent with the theory of epidemiologic transition, has not been well described in children, and the limited research has focused on developed settings. The aim of this study was to describe the relationship between childhood obesity and household income using objective measures of adiposity and to explore how this relationship differs across levels of country human development. METHODS: The International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE) was a multi-national cross-sectional study conducted in 12 urban/suburban study sites that represented all inhabited continents and wide ranges of development. ISCOLE collected objectively measured height, body mass and percentage body fat in 7341 10-year-old children. Multi-level random-effects models were used to examine income gradients in several obesity measures. RESULTS: The mean age of the children was 10.4 years, and 12.6% were obese, ranging from 5.4% (Finland) to 23.8% (China). For both boys and girls, obesity prevalence, body fat percentage and body mass index (BMI) z-score increased linearly with higher income at lower levels of development (all P for trend ⩽0.0012), but decreased linearly with higher income at higher levels of development (all P for trend ⩽0.0003). Country human development explained 75% of the variation in the country-specific income–obesity relationships (r=−0.87, P=0.0003). CONCLUSIONS: Results are consistent with the theory of epidemiologic transition. Global efforts to control obesity must account for socioeconomic factors within a country's context. Future research should seek to understand global socioeconomic patterns in obesity-related lifestyle behaviors. PMID:27152182

  15. The global metabolic transition: Regional patterns and trends of global material flows, 1950-2010.

    PubMed

    Schaffartzik, Anke; Mayer, Andreas; Gingrich, Simone; Eisenmenger, Nina; Loy, Christian; Krausmann, Fridolin

    2014-05-01

    Since the World War II, many economies have transitioned from an agrarian, biomass-based to an industrial, minerals-based metabolic regime. Since 1950, world population grew by factor 2.7 and global material consumption by factor 3.7-71 Gigatonnes per year in 2010. The expansion of the resource base required by human societies is associated with growing pressure on the environment and infringement on the habitats of other species. In order to achieve a sustainability transition, we require a better understanding of the currently ongoing metabolic transition and its potential inertia. In this article, we present a long-term global material flow dataset covering material extraction, trade, and consumption of 177 individual countries between 1950 and 2010. We trace patterns and trends in material flows for six major geographic and economic country groupings and world regions (Western Industrial, the (Former) Soviet Union and its allies, Asia, the Middle East and Northern Africa, Latin America and the Caribbean, and Sub-Saharan Africa) as well as their contribution to the emergence of a global metabolic profile during a period of rapid industrialization and globalization. Global average material use increased from 5.0 to 10.3 tons per capita and year (t/cap/a) between 1950 and 2010. Regional metabolic rates range from 4.5 t/cap/a in Sub-Saharan Africa to 14.8 t/cap/a in the Western Industrial grouping. While we can observe a stabilization of the industrial metabolic profile composed of relatively equal shares of biomass, fossil energy carriers, and construction minerals, we note differences in the degree to which other regions are gravitating toward a similar form of material use. Since 2000, Asia has overtaken the Western Industrial grouping in terms of its share in global resource use although not in terms of its per capita material consumption. We find that at a sub-global level, the roles of the world regions have changed. There are, however, no signs yet that

  16. The global metabolic transition: Regional patterns and trends of global material flows, 1950–2010

    PubMed Central

    Schaffartzik, Anke; Mayer, Andreas; Gingrich, Simone; Eisenmenger, Nina; Loy, Christian; Krausmann, Fridolin

    2014-01-01

    Since the World War II, many economies have transitioned from an agrarian, biomass-based to an industrial, minerals-based metabolic regime. Since 1950, world population grew by factor 2.7 and global material consumption by factor 3.7–71 Gigatonnes per year in 2010. The expansion of the resource base required by human societies is associated with growing pressure on the environment and infringement on the habitats of other species. In order to achieve a sustainability transition, we require a better understanding of the currently ongoing metabolic transition and its potential inertia. In this article, we present a long-term global material flow dataset covering material extraction, trade, and consumption of 177 individual countries between 1950 and 2010. We trace patterns and trends in material flows for six major geographic and economic country groupings and world regions (Western Industrial, the (Former) Soviet Union and its allies, Asia, the Middle East and Northern Africa, Latin America and the Caribbean, and Sub-Saharan Africa) as well as their contribution to the emergence of a global metabolic profile during a period of rapid industrialization and globalization. Global average material use increased from 5.0 to 10.3 tons per capita and year (t/cap/a) between 1950 and 2010. Regional metabolic rates range from 4.5 t/cap/a in Sub-Saharan Africa to 14.8 t/cap/a in the Western Industrial grouping. While we can observe a stabilization of the industrial metabolic profile composed of relatively equal shares of biomass, fossil energy carriers, and construction minerals, we note differences in the degree to which other regions are gravitating toward a similar form of material use. Since 2000, Asia has overtaken the Western Industrial grouping in terms of its share in global resource use although not in terms of its per capita material consumption. We find that at a sub-global level, the roles of the world regions have changed. There are, however, no signs yet

  17. Global Warming and Energy Transition: A Public Policy Imperative

    NASA Astrophysics Data System (ADS)

    Stone, G. T.

    2006-12-01

    The historic transition from fossil fuels to alternative energy resources has begun. This development is commonly attributed to increasing energy costs and the need for energy security. Looming ever larger, however, is the issue that will soon drive the third energy revolution: global warming. A preponderance of evidence documents accelerating warming, enlarging impacts, and human causes -- principally combustion of fossil fuels. The carbon dioxide (C02) content of Earth's atmosphere has increased more than 35 percent since the beginning of the industrial revolution and is the highest in 650,000 years. This dramatic rise of C02 and attendant positive feedbacks are already forcing significant impacts worldwide. These include atmospheric warming with shifting climatic and habitat zones, spreading tropical disease, and more extreme weather events; rapid ice loss at high latitude and high altitude; ocean warming and acidification with coral reef bleaching and intensifying tropical storms; rising sea level; and accelerating extinction rates. The 2007 draft report of the Intergovernmental Panel on Climate Change (IPCC) predicts greater warming than in previous models. A tipping point to abrupt climate change may be imminent. It is incumbent upon geoscientists and geoscience educators to assume leadership in addressing this challenge through public outreach and general education. The following topics should be integrated into all appropriate courses: the evidence of global warming and its causes; observed present and predicted future impacts of global warming; mitigation and adaptation strategies; and implications for energy policies and economic opportunities. New entry-level science and general education courses -- such as Climate Change Fundamentals and Energy in Nature, Technology, and Society -- are proving to be effective should be widely developed In addition, by workshops and presentations to civic and business organizations and by demonstrated examples of

  18. Global Natural Disaster Risk Hotspots: Transition to a Regional Approach

    NASA Astrophysics Data System (ADS)

    Lerner-Lam, A.; Chen, R.; Dilley, M.

    2005-12-01

    The "Hotspots Project" is a collaborative study of the global distribution and occurrence of multiple natural hazards and the associated exposures of populations and their economic output. In this study we assess the global risks of two disaster-related outcomes: mortality and economic losses. We estimate risk levels by combining hazard exposure with historical vulnerability for two indicators of elements at risk-gridded population and Gross Domestic Product (GDP) per unit area - for six major natural hazards: earthquakes, volcanoes, landslides, floods, drought, and cyclones. By calculating relative risks for each grid cell rather than for countries as a whole, we are able to estimate risk levels at sub-national scales. These can then be used to estimate aggregate relative multiple hazard risk at regional and national scales. Mortality-related risks are assessed on a 2.5' x 2.5' latitude-longitude grid of global population (GPW Version 3). Economic risks are assessed at the same resolution for gridded GDP per unit area, using World Bank estimates of GDP based on purchasing power parity. Global hazard data were compiled from multiple sources. The project collaborated directly with UNDP and UNEP, the International Research Institute for Climate Prediction (IRI) at Columbia, and the Norwegian Geotechnical Institute (NGI) in the creation of data sets for several hazards for which global data sets did not previously exist. Drought, flood and volcano hazards are characterized in terms of event frequency, storms by frequency and severity, earthquakes by frequency and ground acceleration exceedance probability, and landslides by an index derived from probability of occurrence. The global analysis undertaken in this project is clearly limited by issues of scale as well as by the availability and quality of data. For some hazards, there exist only 15- to 25-year global records with relatively crude spatial information. Data on historical disaster losses, and particularly on

  19. A symposium and workshop report from the Global Nutrition and Epidemiologic Transition Initiative: nutrition transition and the global burden of type 2 diabetes.

    PubMed

    Mattei, Josiemer; Malik, Vasanti; Wedick, Nicole M; Campos, Hannia; Spiegelman, Donna; Willett, Walter; Hu, Frank B

    2012-10-01

    The present report summarises the symposium 'Nutrition Transition and the Global Burden of Type 2 Diabetes' and a workshop on strategies for dietary interventions to prevent type 2 diabetes held by the Global Nutrition and Epidemiologic Transition Initiative, Boston, MA, USA in November 2011. The objectives of this event were to bring attention to the global epidemic of type 2 diabetes in light of the ongoing nutrition transition worldwide, especially in low- and middle-income countries, and to highlight the present evidence on key dietary risk factors contributing to the global diabetes burden. The meeting put forward ideas for further research on this topic and discussed practical recommendations to design and implement culturally appropriate dietary interventions with a focus on improving carbohydrate quality to help alleviate this growing health problem.

  20. Monitoring and Evaluating the Transition of Large-Scale Programs in Global Health

    PubMed Central

    Bao, James; Rodriguez, Daniela C; Paina, Ligia; Ozawa, Sachiko; Bennett, Sara

    2015-01-01

    Purpose: Donors are increasingly interested in the transition and sustainability of global health programs as priorities shift and external funding declines. Systematic and high-quality monitoring and evaluation (M&E) of such processes is rare. We propose a framework and related guiding questions to systematize the M&E of global health program transitions. Methods: We conducted stakeholder interviews, searched the peer-reviewed and gray literature, gathered feedback from key informants, and reflected on author experiences to build a framework on M&E of transition and to develop guiding questions. Findings: The conceptual framework models transition as a process spanning pre-transition and transition itself and extending into sustained services and outcomes. Key transition domains include leadership, financing, programming, and service delivery, and relevant activities that drive the transition in these domains forward include sustaining a supportive policy environment, creating financial sustainability, developing local stakeholder capacity, communicating to all stakeholders, and aligning programs. Ideally transition monitoring would begin prior to transition processes being implemented and continue for some time after transition has been completed. As no set of indicators will be applicable across all types of health program transitions, we instead propose guiding questions and illustrative quantitative and qualitative indicators to be considered and adapted based on the transition domains identified as most important to the particular health program transition. The M&E of transition faces new and unique challenges, requiring measuring constructs to which evaluators may not be accustomed. Many domains hinge on measuring “intangibles” such as the management of relationships. Monitoring these constructs may require a compromise between rigorous data collection and the involvement of key stakeholders. Conclusion: Monitoring and evaluating transitions in global

  1. A semisynthetic Eph receptor tyrosine kinase provides insight into ligand-induced kinase activation

    PubMed Central

    Singla, Nikhil; Erdjument-Bromage, Hediye; Himanen, Juha P.; Muir, Tom W.; Nikolov, Dimitar B.

    2011-01-01

    SUMMARY We have developed a methodology for generating milligram amounts of functional Eph tyrosine kinase receptor using the protein engineering approach of expressed protein ligation. Stimulation with ligand induces efficient autophosphorylation of the semisynthetic Eph construct. The in vitro phosphorylation of key Eph tyrosine residues upon ligand-induced activation was monitored via time-resolved, quantitative phosphoproteomics, suggesting a precise and unique order of phosphorylation of the Eph tyrosines in the kinase activation process. To our knowledge, this work represents the first reported semisynthesis of a receptor tyrosine kinase and provides a potentially general method for producing single-pass membrane proteins for structural and biochemical characterization. PMID:21439481

  2. Global Shifts in Cardiovascular Disease, the Epidemiologic Transition, and Other Contributing Factors: Toward a New Practice of Global Health Cardiology.

    PubMed

    Mendoza, Walter; Miranda, J Jaime

    2017-02-01

    One of the major drivers of change in the practice of cardiology is population change. This article discusses the current debate about epidemiologic transition paired with other ongoing transitions with direct relevance to cardiovascular conditions. Challenges specific to patterns of risk factors over time; readiness for disease surveillance and meeting global targets; health system, prevention, and treatment efforts; and physiologic traits and human-environment interactions are identified. This article concludes that a focus on the most populated regions of the world will contribute substantially to protecting the large gains in global survival and life expectancy accrued over the last decades.

  3. Ethnography of epidemiologic transition: Avian flu, global health politics and agro-industrial capitalism in Thailand.

    PubMed

    Chuengsatiansup, Komatra

    2008-04-01

    This paper situates the ethnography of avian flu within the geo-political context of a new epidemiologic transition. Drawing on anthropological experience and insight, this paper examines areas of enquiry in which an ethnographic approach could contribute to a better implementation of prevention and control measures. Within the context of newly emerging diseases and accelerated globalization, the task of ethnography needs to extend far beyond the local. This paper reveals two major global issues that the ethnography of epidemiologic transition must take into consideration: (1) Global agro-industrial capitalism, and (2) global politics in the context of international health organizations and multi-national drug companies. The case of Thailand poses a question of how the strength of ethnographic practice could be deployed to account for the reality of the global-local interface of the new epidemiologic transition.

  4. Global epidemic invasion thresholds in directed cattle subpopulation networks having source, sink, and transit nodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Through the characterization of a metapopulation cattle disease model on a directed network having source, transit, and sink nodes, we derive two global epidemic invasion thresholds. The first threshold defines the conditions necessary for an epidemic to successfully spread at the global scale. The ...

  5. The Research University in Transition: The Emerging Global Model

    ERIC Educational Resources Information Center

    Mohrman, Kathryn; Ma, Wanhua; Baker, David

    2008-01-01

    In a knowledge intensive society, the research university is a key institution for social and economic development. Focused on the discovery of new knowledge and the development of the next generation of scholars, research universities are also becoming more international in focus. This article presents the Emerging Global Model (EGM) of the…

  6. Global cooling during the eocene-oligocene climate transition.

    PubMed

    Liu, Zhonghui; Pagani, Mark; Zinniker, David; Deconto, Robert; Huber, Matthew; Brinkhuis, Henk; Shah, Sunita R; Leckie, R Mark; Pearson, Ann

    2009-02-27

    About 34 million years ago, Earth's climate shifted from a relatively ice-free world to one with glacial conditions on Antarctica characterized by substantial ice sheets. How Earth's temperature changed during this climate transition remains poorly understood, and evidence for Northern Hemisphere polar ice is controversial. Here, we report proxy records of sea surface temperatures from multiple ocean localities and show that the high-latitude temperature decrease was substantial and heterogeneous. High-latitude (45 degrees to 70 degrees in both hemispheres) temperatures before the climate transition were approximately 20 degrees C and cooled an average of approximately 5 degrees C. Our results, combined with ocean and ice-sheet model simulations and benthic oxygen isotope records, indicate that Northern Hemisphere glaciation was not required to accommodate the magnitude of continental ice growth during this time.

  7. Persistent global power fluctuations near a dynamic transition in electroconvection.

    PubMed

    Tóth-Katona, Tibor; Cressman, John R; Goldburg, Walter I; Gleeson, James T

    2003-09-01

    This is a study of the global fluctuations in power injection and light transmission through a liquid crystal just above the onset of electroconvection. The source of the fluctuations is identified as the creation and annihilation of defects. They are spatially uncorrelated and yet temporally correlated. The temporal correlation is seen to persist for extremely long times. There seems to be an especially close relation between defect creation or annihilation in electroconvection and thermal plumes in Rayleigh-Bénard convection.

  8. Tibetan plateau aridification linked to global cooling at the Eocene-Oligocene transition.

    PubMed

    Dupont-Nivet, Guillaume; Krijgsman, Wout; Langereis, Cor G; Abels, Hemmo A; Dai, Shuang; Fang, Xiaomin

    2007-02-08

    Continental aridification and the intensification of the monsoons in Asia are generally attributed to uplift of the Tibetan plateau and to the land-sea redistributions associated with the continental collision of India and Asia, whereas some studies suggest that past changes in Asian environments are mainly governed by global climate. The most dramatic climate event since the onset of the collision of India and Asia is the Eocene-Oligocene transition, an abrupt cooling step associated with the onset of glaciation in Antarctica 34 million years ago. However, the influence of this global event on Asian environments is poorly understood. Here we use magnetostratigraphy and cyclostratigraphy to show that aridification, which is indicated by the disappearance of playa lake deposits in the northeastern Tibetan plateau, occurred precisely at the time of the Eocene-Oligocene transition. Our findings suggest that this global transition is linked to significant aridification and cooling in continental Asia recorded by palaeontological and palaeoenvironmental changes, and thus support the idea that global cooling is associated with the Eocene-Oligocene transition. We show that, with sufficient age control on the sedimentary records, global climate can be distinguished from tectonism and recognized as a major contributor to continental Asian environments.

  9. Transitional states in marine fisheries: adapting to predicted global change

    PubMed Central

    MacNeil, M. Aaron; Graham, Nicholas A. J.; Cinner, Joshua E.; Dulvy, Nicholas K.; Loring, Philip A.; Jennings, Simon; Polunin, Nicholas V. C.; Fisk, Aaron T.; McClanahan, Tim R.

    2010-01-01

    Global climate change has the potential to substantially alter the production and community structure of marine fisheries and modify the ongoing impacts of fishing. Fish community composition is already changing in some tropical, temperate and polar ecosystems, where local combinations of warming trends and higher environmental variation anticipate the changes likely to occur more widely over coming decades. Using case studies from the Western Indian Ocean, the North Sea and the Bering Sea, we contextualize the direct and indirect effects of climate change on production and biodiversity and, in turn, on the social and economic aspects of marine fisheries. Climate warming is expected to lead to (i) yield and species losses in tropical reef fisheries, driven primarily by habitat loss; (ii) community turnover in temperate fisheries, owing to the arrival and increasing dominance of warm-water species as well as the reduced dominance and departure of cold-water species; and (iii) increased diversity and yield in Arctic fisheries, arising from invasions of southern species and increased primary production resulting from ice-free summer conditions. How societies deal with such changes will depend largely on their capacity to adapt—to plan and implement effective responses to change—a process heavily influenced by social, economic, political and cultural conditions. PMID:20980322

  10. Transitional states in marine fisheries: adapting to predicted global change.

    PubMed

    MacNeil, M Aaron; Graham, Nicholas A J; Cinner, Joshua E; Dulvy, Nicholas K; Loring, Philip A; Jennings, Simon; Polunin, Nicholas V C; Fisk, Aaron T; McClanahan, Tim R

    2010-11-27

    Global climate change has the potential to substantially alter the production and community structure of marine fisheries and modify the ongoing impacts of fishing. Fish community composition is already changing in some tropical, temperate and polar ecosystems, where local combinations of warming trends and higher environmental variation anticipate the changes likely to occur more widely over coming decades. Using case studies from the Western Indian Ocean, the North Sea and the Bering Sea, we contextualize the direct and indirect effects of climate change on production and biodiversity and, in turn, on the social and economic aspects of marine fisheries. Climate warming is expected to lead to (i) yield and species losses in tropical reef fisheries, driven primarily by habitat loss; (ii) community turnover in temperate fisheries, owing to the arrival and increasing dominance of warm-water species as well as the reduced dominance and departure of cold-water species; and (iii) increased diversity and yield in Arctic fisheries, arising from invasions of southern species and increased primary production resulting from ice-free summer conditions. How societies deal with such changes will depend largely on their capacity to adapt--to plan and implement effective responses to change--a process heavily influenced by social, economic, political and cultural conditions.

  11. Nutrition in transition: the changing global nutrition challenge.

    PubMed

    Popkin, B M

    2001-01-01

    The rapid shift in the stage of nutrition towards a pattern of degenerative disease is accelerating in the developing world. Data from China, as shown by the China Health and Nutrition Survey, between 1989 and 1993, are illustrative of these shifts. For example, an increase from 22.8 to 66.6% in the proportion of adults consuming a higher-fat diet, rapid shifts in the structure of diet as income changes, and important price relationships are examples that are presented. There appears to reflect a basic shift in eating preferences, induced mainly by shifts in income, prices and food availability, but also by the modern food industry and the mass media. Furthermore, the remarkable shift in the occupations structure in lower-income countries from agricultural labour towards employment in manufacturing and services implies a reduction in energy expenditure. One consequence of the nutrition transition has been a decline in undernutrition accompanied by a rapid increase in obesity. There are marked differences between urban and rural eating patterns, particularly regarding the consumption of food prepared away from home. Other issues considered are the fetal origins hypothesis, whereby the metabolic efficiencies that served well in conditions of fetal undernutrition become maladaptive with overnutrition, leading to the development of abnormal lipid profiles, altered glucose and insulin metabolism and obesity. Furthermore, obesity and activity are closely linked with adult-onset diabetes. The shift towards a diet higher in fat and meat and lower in carbohydrates and fibre, together with the shift towards less onerous physical activity, carries unwanted nutritional and health effects. It is also clear that the causes of obesity must be viewed as environmental rather than personal or genetic.

  12. Modeling the Oil Transition: A Summary of the Proceedings of the DOE/EPA Workshop on the Economic and Environmental Implications of Global Energy Transitions

    SciTech Connect

    Greene, David L

    2007-02-01

    The global energy system faces sweeping changes in the next few decades, with potentially critical implications for the global economy and the global environment. It is important that global institutions have the tools necessary to predict, analyze and plan for such massive change. This report summarizes the proceedings of an international workshop concerning methods of forecasting, analyzing, and planning for global energy transitions and their economic and environmental consequences. A specific case, it focused on the transition from conventional to unconventional oil and other energy sources likely to result from a peak in non-OPEC and/or global production of conventional oil. Leading energy models from around the world in government, academia and the private sector met, reviewed the state-of-the-art of global energy modeling and evaluated its ability to analyze and predict large-scale energy transitions.

  13. Princess Nourah Bint Abudulrhman University's Challenge: Transition from a Local to a Global Institution

    ERIC Educational Resources Information Center

    Almansour, Sana; Kempner, Ken

    2015-01-01

    This case study addresses the transition of a university from a local to a global institution in the unique cultural and economic circumstances of the Kingdom of Saudi Arabia. Specifically, the authors investigate the case of Princess Nourah Bint Abudulrhman University (PNU), the largest women's university in the world with over 39,000 students.…

  14. Protein Kinase Cβ Modulates Ligand-induced Cell Surface Death Receptor Accumulation

    PubMed Central

    Meng, Xue Wei; Heldebrant, Michael P.; Flatten, Karen S.; Loegering, David A.; Dai, Haiming; Schneider, Paula A.; Gomez, Timothy S.; Peterson, Kevin L.; Trushin, Sergey A.; Hess, Allan D.; Smith, B. Douglas; Karp, Judith E.; Billadeau, Daniel D.; Kaufmann, Scott H.

    2010-01-01

    Although treatment with the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) is known to protect a subset of cells from induction of apoptosis by death ligands such as Fas ligand and tumor necrosis factor-α-related apoptosis-inducing ligand, the mechanism of this protection is unknown. This study demonstrated that protection in short term apoptosis assays and long term proliferation assays was maximal when Jurkat or HL-60 human leukemia cells were treated with 2–5 nm PMA. Immunoblotting demonstrated that multiple PKC isoforms, including PKCα, PKCβ, PKCϵ, and PKCθ, translocated from the cytosol to a membrane-bound fraction at these PMA concentrations. When the ability of short hairpin RNA (shRNA) constructs that specifically down-regulated each of these isoforms was examined, PKCβ shRNA uniquely reversed PMA-induced protection against cell death. The PKCβ-selective small molecule inhibitor enzastaurin had a similar effect. Although mass spectrometry suggested that Fas is phosphorylated on a number of serines and threonines, mutation of these sites individually or collectively had no effect on Fas-mediated death signaling or PMA protection. Further experiments demonstrated that PMA diminished ligand-induced cell surface accumulation of Fas and DR5, and PKCβ shRNA or enzastaurin reversed this effect. Moreover, enzastaurin sensitized a variety of human tumor cell lines and clinical acute myelogenous leukemia isolates, which express abundant PKCβ, to tumor necrosis factor-α related apoptosis-inducing ligand-induced death in the absence of PMA. Collectively, these results identify a specific PKC isoform that modulates death receptor-mediated cytotoxicity as well as a small molecule inhibitor that mitigates the inhibitory effects of PKC activation on ligand-induced death receptor trafficking and cell death. PMID:19887445

  15. Columbus State University Global Observation and Outreach for the 2012 Transit of Venus

    NASA Astrophysics Data System (ADS)

    Perry, Matthew; McCarty, C.; Bartow, M.; Hood, J. C.; Lodder, K.; Johnson, M.; Cruzen, S. T.; Williams, R. N.

    2013-01-01

    Faculty, staff and students from Columbus State University’s (CSU’s) Coca-Cola Space Science Center presented a webcast of the 2012 Transit of Venus from three continents to a global audience of 1.4 million unique viewers. Team members imaged the transit with telescopes using white-light, hydrogen-alpha, and calcium filters, from Alice Springs, Australia; the Gobi Desert, Mongolia; Bryce Canyon, UT; and Columbus, GA. Images were webcast live during the transit in partnership with NASA’s Sun-Earth Day program, and Science Center staff members were featured on NASA TV. Local members of the public were brought in for a series of outreach initiatives, in both Georgia and Australia, before and during the transit. The data recorded from the various locations have been archived for use in demonstrating principles such as the historical measurement of the astronomical unit.

  16. The Global Epidemiologic Transition: Noncommunicable Diseases and Emerging Health Risk of Allergic Disease in Sub-Saharan Africa

    ERIC Educational Resources Information Center

    Atiim, George A.; Elliott, Susan J.

    2016-01-01

    Globally, there has been a shift in the causes of illness and death from infectious diseases to noncommunicable diseases. This changing pattern has been attributed to the effects of an (ongoing) epidemiologic transition. Although researchers have applied epidemiologic transition theory to questions of global health, there have been relatively few…

  17. The Global Polio Eradication Initiative: Progress, Lessons Learned, And Polio Legacy Transition Planning.

    PubMed

    Cochi, Stephen L; Hegg, Lea; Kaur, Anjali; Pandak, Carol; Jafari, Hamid

    2016-02-01

    The world is closer than ever to achieving global polio eradication, with record-low polio cases in 2015 and the impending prospect of a polio-free Africa. Tens of millions of volunteers, social mobilizers, and health workers have participated in the Global Polio Eradication Initiative. The program contributes to efforts to deliver other health benefits, including health systems strengthening. As the initiative nears completion after more than twenty-five years, it becomes critical to document and transition the knowledge, lessons learned, assets, and infrastructure accumulated by the initiative to address other health goals and priorities. The primary goals of this process, known as polio legacy transition planning, are both to protect a polio-free world and to ensure that investments in polio eradication will contribute to other health goals after polio is completely eradicated. The initiative is engaged in an extensive transition process of consultations and planning at the global, regional, and country levels. A successful completion of this process will result in a well-planned and -managed conclusion of the initiative that will secure the global public good gained by ending one of the world's most devastating diseases and ensure that these investments provide public health benefits for years to come.

  18. Transition process of abrupt climate change based on global sea surface temperature over the past century

    NASA Astrophysics Data System (ADS)

    Yan, Pengcheng; Hou, Wei; Feng, Guolin

    2016-05-01

    A new detection method has been proposed to study the transition process of abrupt climate change. With this method, the climate system transiting from one stable state to another can be verified clearly. By applying this method to the global sea surface temperature over the past century, several climate changes and their processes are detected, including the start state (moment), persist time, and end state (moment). According to the spatial distribution, the locations of climate changes mainly have occurred in the Indian Ocean and western Pacific before the middle twentieth century, in the 1970s in the equatorial middle-eastern Pacific, and in the middle and southern Pacific since the end of the twentieth century. In addition, the quantitative relationship between the transition process parameters is verified in theory and practice: (1) the relationship between the rate and stability parameters is linear, and (2) the relationship between the rate and change amplitude parameters is quadratic.

  19. Phase transitions in a Bose-Hubbard model with cavity-mediated global-range interactions

    NASA Astrophysics Data System (ADS)

    Dogra, N.; Brennecke, F.; Huber, S. D.; Donner, T.

    2016-08-01

    We study a system with competing short- and global-range interactions in the framework of the Bose-Hubbard model. Using a mean-field approximation we obtain the phase diagram of the system and observe four different phases: a superfluid, a supersolid, a Mott insulator, and a charge-density wave, where the transitions between the various phases can be either of first or second order. We qualitatively support these results using Monte Carlo simulations. An analysis of the low-energy excitations shows that the second-order phase transition from the charge-density wave to the supersolid is associated with the softening of particle- and holelike excitations which give rise to a gapless mode and an amplitude Higgs mode in the supersolid phase. This amplitude Higgs mode is further transformed into a roton mode which softens at the supersolid to superfluid phase transition.

  20. The thrombin receptor extracellular domain contains sites crucial for peptide ligand-induced activation.

    PubMed Central

    Bahou, W F; Coller, B S; Potter, C L; Norton, K J; Kutok, J L; Goligorsky, M S

    1993-01-01

    A thrombin receptor (TR) demonstrating a unique activation mechanism has recently been isolated from a megakaryocytic (Dami) cell line. To further study determinants of peptide ligand-mediated activation phenomenon, we have isolated, cloned, and stably expressed the identical receptor from a human umbilical vein endothelial cell (HUVEC) library. Chinese hamster ovary (CHO) cells expressing a functional TR (CHO-TR), platelets, and HUVECs were then used to specifically characterize alpha-thrombin- and peptide ligand-induced activation responses using two different antibodies: anti-TR34-52 directed against a 20-amino acid peptide spanning the thrombin cleavage site, and anti-TR1-160 generated against the NH2-terminal 160 amino acids of the TR expressed as a chimeric protein in Escherichia coli. Activation-dependent responses to both alpha-thrombin (10 nM) and peptide ligand (20 microM) were studied using fura 2-loaded cells and microspectrofluorimetry. Whereas preincubation of CHO-TR with anti-TR34-52 abolished only alpha-thrombin-induced [Ca2+]i transients, preincubation with anti-TR1-160 abrogated both alpha-thrombin- and peptide ligand-induced responses. This latter inhibitory effect was dose dependent and similar for both agonists, with an EC50 of approximately 90 micrograms/ml. Anti-TR1-160 similarly abolished peptide ligand-induced [Ca2+]i transients in platelets and HUVECs, whereas qualitatively different responses characterized by delayed but sustained elevations in [Ca2+]i transients were evident using alpha-thrombin. Platelet aggregation to low concentrations of both ligands was nearly abolished by anti-TR1-160, although some shape change remained; anti-TR34-52 only inhibited alpha-thrombin-induced aggregation. These data establish that a critical recognition sequence for peptide ligand-mediated receptor activation is contained on the NH2-terminal portion of the receptor, upstream from the first transmembrane domain. Furthermore, alpha

  1. Global Infrared Observations of Roughness Induced Transition on the Space Shuttle Orbiter

    NASA Technical Reports Server (NTRS)

    Horvath, Thomas J.; Zalameda, Joseph N.; Wood, William A.; Berry, Scott A.; Schwartz, Richard J.; Dantowitz, Ronald F.; Spisz, Thomas S.; Taylor, Jeff C.

    2012-01-01

    High resolution infrared observations made from a mobile ground based optical system captured the laminar-to-turbulent boundary layer transition process as it occurred during Space Shuttle Endeavour's return to earth following its final mission in 2011. The STS-134 imagery was part of a larger effort to demonstrate an emerging and reliable non-intrusive global thermal measurement capability and to complement a series of boundary layer transition flight experiments that were flown on the Shuttle. The STS-134 observations are believed to be the first time that the development and movement of a hypersonic boundary layer transition front has been witnessed in flight over the entire vehicle surface and in particular, at unprecedented spatial resolution. Additionally, benchmark surface temperature maps of the Orbiter lower surface collected over multiple flights and spanning a Mach range of 18 to 6 are now available and represent an opportunity for collaborative comparison with computational techniques focused on hypersonic transition and turbulence modeling. The synergy of the global temperature maps with the companion in-situ thermocouple measurements serve as an example of the effective leveraging of resources to achieve a common goal of advancing our understanding of the complex nature of high Mach number transition. It is shown that quantitative imaging can open the door to a multitude of national and international opportunities for partnership associated with flight-testing and subsequent validation of numerical simulation techniques. The quantitative imaging applications highlighted in this paper offer unique and complementary flight measurement alternatives and suggest collaborative instrumentation opportunities to advance the state of the art in transition prediction and maximize the return on investment in terms of developmental flight tests for future vehicle designs.

  2. Heterogeneity in global vegetation and terrestrial climate change during the late Eocene to early Oligocene transition.

    PubMed

    Pound, Matthew J; Salzmann, Ulrich

    2017-02-24

    Rapid global cooling at the Eocene - Oligocene Transition (EOT), ~33.9-33.5 Ma, is widely considered to mark the onset of the modern icehouse world. A large and rapid drop in atmospheric pCO2 has been proposed as the driving force behind extinctions in the marine realm and glaciation on Antarctica. However, the global terrestrial response to this cooling is uncertain. Here we present the first global vegetation and terrestrial temperature reconstructions for the EOT. Using an extensive palynological dataset, that has been statistically grouped into palaeo-biomes, we show a more transitional nature of terrestrial climate change by indicating a spatial and temporal heterogeneity of vegetation change at the EOT in both hemispheres. The reconstructed terrestrial temperatures show for many regions a cooling that started well before the EOT and continued into the Early Oligocene. We conclude that the heterogeneous pattern of global vegetation change has been controlled by a combination of multiple forcings, such as tectonics, sea-level fall and long-term decline in greenhouse gas concentrations during the late Eocene to early Oligocene, and does not represent a single response to a rapid decline in atmospheric pCO2 at the EOT.

  3. Heterogeneity in global vegetation and terrestrial climate change during the late Eocene to early Oligocene transition

    NASA Astrophysics Data System (ADS)

    Pound, Matthew J.; Salzmann, Ulrich

    2017-02-01

    Rapid global cooling at the Eocene – Oligocene Transition (EOT), ~33.9–33.5 Ma, is widely considered to mark the onset of the modern icehouse world. A large and rapid drop in atmospheric pCO2 has been proposed as the driving force behind extinctions in the marine realm and glaciation on Antarctica. However, the global terrestrial response to this cooling is uncertain. Here we present the first global vegetation and terrestrial temperature reconstructions for the EOT. Using an extensive palynological dataset, that has been statistically grouped into palaeo-biomes, we show a more transitional nature of terrestrial climate change by indicating a spatial and temporal heterogeneity of vegetation change at the EOT in both hemispheres. The reconstructed terrestrial temperatures show for many regions a cooling that started well before the EOT and continued into the Early Oligocene. We conclude that the heterogeneous pattern of global vegetation change has been controlled by a combination of multiple forcings, such as tectonics, sea-level fall and long-term decline in greenhouse gas concentrations during the late Eocene to early Oligocene, and does not represent a single response to a rapid decline in atmospheric pCO2 at the EOT.

  4. Heterogeneity in global vegetation and terrestrial climate change during the late Eocene to early Oligocene transition

    PubMed Central

    Pound, Matthew J.; Salzmann, Ulrich

    2017-01-01

    Rapid global cooling at the Eocene – Oligocene Transition (EOT), ~33.9–33.5 Ma, is widely considered to mark the onset of the modern icehouse world. A large and rapid drop in atmospheric pCO2 has been proposed as the driving force behind extinctions in the marine realm and glaciation on Antarctica. However, the global terrestrial response to this cooling is uncertain. Here we present the first global vegetation and terrestrial temperature reconstructions for the EOT. Using an extensive palynological dataset, that has been statistically grouped into palaeo-biomes, we show a more transitional nature of terrestrial climate change by indicating a spatial and temporal heterogeneity of vegetation change at the EOT in both hemispheres. The reconstructed terrestrial temperatures show for many regions a cooling that started well before the EOT and continued into the Early Oligocene. We conclude that the heterogeneous pattern of global vegetation change has been controlled by a combination of multiple forcings, such as tectonics, sea-level fall and long-term decline in greenhouse gas concentrations during the late Eocene to early Oligocene, and does not represent a single response to a rapid decline in atmospheric pCO2 at the EOT. PMID:28233862

  5. Global vegetation distribution and terrestrial climate evolution at the Eocene-Oligocene transition

    NASA Astrophysics Data System (ADS)

    Pound, Matthew; Salzmann, Ulrich

    2016-04-01

    The Eocene - Oligocene transition (EOT; ca. 34-33.5 Ma) is widely considered to be the biggest step in Cenozoic climate evolution. Geochemical marine records show both surface and bottom water cooling, associated with the expansion of Antarctic glaciers and a reduction in the atmospheric CO2 concentration. However, the global response of the terrestrial biosphere to the EOT is less well understood and not uniform when comparing different regions. We present new global vegetation and terrestrial climate reconstructions of the Priabonian (late Eocene; 38-33.9 Ma) and Rupelian (early Oligocene; 33.9-28.45 Ma) by synthesising 215 pollen and spore localities. Using presence/absence data of pollen and spores with multivariate statistics has allowed the reconstruction of palaeo-biomes without relying on modern analogues. The reconstructed palaeo-biomes do not show the equator-ward shift at the EOT, which would be expected from a global cooling. Reconstructions of mean annual temperature, cold month mean temperature and warm month mean temperature do not show a global cooling of terrestrial climate across the EOT. Our new reconstructions differ from previous global syntheses by being based on an internally consistent statistically defined classification of palaeo-biomes and our terrestrial based climate reconstructions are in stark contrast to some marine based climate estimates. Our results raise new questions on the nature and extent of terrestrial global climate change at the EOT.

  6. Dynamics, flexibility and ligand-induced conformational changes in biological macromolecules: a computational approach.

    PubMed

    Skjaerven, Lars; Reuter, Nathalie; Martinez, Aurora

    2011-12-01

    Biomolecules possess important dynamical properties that enable them to adapt and alternate their conformation as a response to environmental stimuli. Recent advancements in computational resources and methodology allow a higher capability to mimic in vitro conditions and open up the possibility of studying large systems over longer timescales. Here, we describe commonly used computational approaches for studying the dynamic properties of proteins. We review a selected set of simulation studies on ligand-induced changes in the chaperonin GroEL-GroES, a molecular folding machine, maltose-binding protein, a prototypical member of the periplasmic binding proteins, and the bacterial ribosomal A-site, focusing on aminoglycoside antibiotic recognition. We also discuss a recent quantitative reconstruction of the binding process of benzamidine and trypsin. These studies contribute to the understanding and further development of the medicinal regulation of large biomolecular systems.

  7. Global seismic data reveal little water in the mantle transition zone

    NASA Astrophysics Data System (ADS)

    Houser, C.

    2016-08-01

    Knowledge of the Earth's present water content is necessary to constrain the amount of water and other volatiles the Earth acquired during its formation and the amount that is cycled back into the interior from the surface. This study compares 410 and 660 km discontinuity depth with shear wave tomography within the mantle transition zone to identify regions with seismic signals consistent with water. The depth of the 410 and 660 km discontinuities is determined from a large updated dataset of SS-S410S and SS-S660S differential travel times, known as SS precursors. The discontinuity depths measured from binning and stacking the SS precursor data are then compared to the shear velocity model HMSL-S06 in the transition zone. Mapping all the possible combinations, very few locations match the predictions from mineral physics for the effects of water on discontinuity depth and shear velocity. The predictions, although not yet measured at actual transition zone temperatures and pressures, are a shallow 410 km discontinuity, a deep 660 km discontinuity, and a slow shear velocity. Only 8% of the bins with high-quality data are consistent with these predictions, and the calculated average water content within these bins is around 0.6 wt.%. A few isolated locations have patterns of velocity/topography that are consistent with water, while there are large regional-scale patterns consistent with cold/hot temperature anomalies. Combining this global analysis of long period seismic data and the current mineral physics predictions for water in transition zone minerals, I find that the mantle transition zone is generally dry, containing less than one Earth ocean of water. Although subduction zones could be locally hydrated, the combined discontinuity and velocity data show no evidence that wadsleyite or ringwoodite have been globally hydrated by subduction or initial Earth conditions.

  8. Global distribution of azimuthal anisotropy within the lithosphere, asthenosphere, and transition zone

    NASA Astrophysics Data System (ADS)

    Schaeffer, Andrew; Lebedev, Sergei

    2015-04-01

    We present our new global, azimuthally anisotropic model of the upper mantle, crust, and transition zone. We compare two versions of this new model, the rough SL2013svAr and smooth SL2013svA, which are constrained by a larger, updated waveform fit dataset (>900, 000 vertical component seismogram fits) than that used in the construction of the isotropic model SL2013sv (Schaeffer and Lebedev, 2013). These two anisotropy models are computed using a more precise regularization of anisotropy, which is tuned to honour the both the amplitude and orientation of the anisotropic terms uniformly, including near the poles. Automated, multimode waveform inversion was used to extract structural information from surface and S wave forms, yielding resolving power from the crust down to the transition zone. Our unprecedentedly large waveform dataset, with complementary high-resolution regional array subsets within larger global networks, produces improved resolution of global azimuthal anisotropy patterns. The model also reveals smaller scale patterns of 3D anisotropy variations related to regional lithospheric deformation and mantle flow, in particular in densely sampled regions. In oceanic regions, we examine the strength of azimuthal anisotropy, as a function of depth, spatial position with respect to the spreading ridge, and deviation in fast axis orientation from the current and fossil spreading directions. Furthermore, we explore correlations between anisotropic tomography models and a new reference frame developed such that the net rotation of spreading ridges is minimized (RNR; Becker et al, 2014). In continental regions, azimuthal anisotropy is more complex. Reconciling complementary observations given by shear wave splitting, surface-wave array analysis, and large-scale, global 3D models offers new insights into the mechanisms of continental deformation and the architecture and evolution of the lithosphere. Finally, quantitative comparisons with other recently published

  9. Global Transition Zone Anisotropy and Consequences for Mantle Flow and Earth's Deep Water Cycle

    NASA Astrophysics Data System (ADS)

    Beghein, C.; Yuan, K.

    2011-12-01

    The transition zone has long been at the center of the debate between multi- and single-layered convection models that directly relate to heat transport and chemical mixing throughout the mantle. It has also been suggested that the transition zone is a reservoir that collects water transported by subduction of the lithosphere into the mantle. Since water lowers mantle minerals density and viscosity, thereby modifying their rheology and melting behavior, it likely affects global mantle dynamics and the history of plate tectonics. Constraining mantle flow is therefore important for our understanding of Earth's thermochemical evolution and deep water cycle. Because it can result from deformation by dislocation creep during convection, seismic anisotropy can help us model mantle flow. It is relatively well constrained in the uppermost mantle, but its presence in the transition zone is still debated. Its detection below 250 km depth has been challenging to date because of the poor vertical resolution of commonly used datasets. In this study, we used global Love wave overtone phase velocity maps, which are sensitive to structure down to much larger depths than fundamental modes alone, and have greater depth resolution than shear wave-splitting data. This enabled us to obtain a first 3-D model of azimuthal anisotropy for the upper 800km of the mantle. We inverted the 2Ψ terms of anisotropic phase velocity maps [Visser, et al., 2008] for the first five Love wave overtones between 35s and 174s period. The resulting model shows that the average anisotropy amplitude for vertically polarized shear waves displays two main stable peaks: one in the uppermost mantle and, most remarkably, one in the lower transition zone. F-tests showed that the presence of 2Ψ anisotropy in the transition zone is required to improve the third, fourth, and fifth overtones fit. Because of parameter trade-offs, however, we cannot exclude that the anisotropy is located in the upper transition zone as

  10. Global transition path search for dislocation formation in Ge on Si(001)

    NASA Astrophysics Data System (ADS)

    Maras, E.; Trushin, O.; Stukowski, A.; Ala-Nissila, T.; Jónsson, H.

    2016-08-01

    Global optimization of transition paths in complex atomic scale systems is addressed in the context of misfit dislocation formation in a strained Ge film on Si(001). Such paths contain multiple intermediate minima connected by minimum energy paths on the energy surface emerging from the atomic interactions in the system. The challenge is to find which intermediate states to include and to construct a path going through these intermediates in such a way that the overall activation energy for the transition is minimal. In the numerical approach presented here, intermediate minima are constructed by heredity transformations of known minimum energy structures and by identifying local minima in minimum energy paths calculated using a modified version of the nudged elastic band method. Several mechanisms for the formation of a 90° misfit dislocation at the Ge-Si interface are identified when this method is used to construct transition paths connecting a homogeneously strained Ge film and a film containing a misfit dislocation. One of these mechanisms which has not been reported in the literature is detailed. The activation energy for this path is calculated to be 26% smaller than the activation energy for half loop formation of a full, isolated 60° dislocation. An extension of the common neighbor analysis method involving characterization of the geometrical arrangement of second nearest neighbors is used to identify and visualize the dislocations and stacking faults.

  11. Visualization and ligand-induced modulation of dopamine receptor dimerization at the single molecule level

    PubMed Central

    Tabor, Alina; Weisenburger, Siegfried; Banerjee, Ashutosh; Purkayastha, Nirupam; Kaindl, Jonas M.; Hübner, Harald; Wei, Luxi; Grömer, Teja W.; Kornhuber, Johannes; Tschammer, Nuska; Birdsall, Nigel J. M.; Mashanov, Gregory I.; Sandoghdar, Vahid; Gmeiner, Peter

    2016-01-01

    G protein–coupled receptors (GPCRs), including dopamine receptors, represent a group of important pharmacological targets. An increased formation of dopamine receptor D2 homodimers has been suggested to be associated with the pathophysiology of schizophrenia. Selective labeling and ligand-induced modulation of dimerization may therefore allow the investigation of the pathophysiological role of these dimers. Using TIRF microscopy at the single molecule level, transient formation of homodimers of dopamine receptors in the membrane of stably transfected CHO cells has been observed. The equilibrium between dimers and monomers was modulated by the binding of ligands; whereas antagonists showed a ratio that was identical to that of unliganded receptors, agonist-bound D2 receptor-ligand complexes resulted in an increase in dimerization. Addition of bivalent D2 receptor ligands also resulted in a large increase in D2 receptor dimers. A physical interaction between the protomers was confirmed using high resolution cryogenic localization microscopy, with ca. 9 nm between the centers of mass. PMID:27615810

  12. Ligand-induced EGF Receptor Oligomerization Is Kinase-dependent and Enhances Internalization*

    PubMed Central

    Hofman, Erik G.; Bader, Arjen N.; Voortman, Jarno; van den Heuvel, Dave J.; Sigismund, Sara; Verkleij, Arie J.; Gerritsen, Hans C.; van Bergen en Henegouwen, Paul M. P.

    2010-01-01

    The current activation model of the EGF receptor (EGFR) predicts that binding of EGF results in dimerization and oligomerization of the EGFR, leading to the allosteric activation of the intracellular tyrosine kinase. Little is known about the regulatory mechanism of receptor oligomerization. In this study, we have employed FRET between identical fluorophores (homo-FRET) to monitor the dimerization and oligomerization state of the EGFR before and after receptor activation. Our data show that, in the absence of ligand, ∼40% of the EGFR molecules were present as inactive dimers or predimers. The monomer/predimer ratio was not affected by deletion of the intracellular domain. Ligand binding induced the formation of receptor oligomers, which were found in both the plasma membrane and intracellular structures. Ligand-induced oligomerization required tyrosine kinase activity and nine different tyrosine kinase substrate residues. This indicates that the binding of signaling molecules to activated EGFRs results in EGFR oligomerization. Induction of EGFR predimers or pre-oligomers using the EGFR fused to the FK506-binding protein did not affect signaling but was found to enhance EGF-induced receptor internalization. Our data show that EGFR oligomerization is the result of EGFR signaling and enhances EGFR internalization. PMID:20940297

  13. Regulation of Cre recombinase by ligand-induced complementation of inactive fragments

    PubMed Central

    Jullien, Nicolas; Sampieri, François; Enjalbert, Alain; Herman, Jean-Paul

    2003-01-01

    Cre recombinase is extensively used to engineer the genome of experimental animals. However, its usefulness is still limited by the lack of an efficient temporal control over its activity. To overcome this, we have developed DiCre, a regulatable fragment complementation system for Cre. The enzyme was split into two moieties that were fused to FKBP12 (FK506-binding protein) and FRB (binding domain of the FKBP12–rapamycin-associated protein), respectively. These can be efficiently heterodimerized by rapamycin. Several variants, based on splitting Cre at different sites and using different linker peptides, were tested in an indicator cell line. The fusion proteins, taken separately, had no recombinase activity. Stable transformants, co-expressing complementing fragments based on splitting Cre between Asn59 and Asn60, displayed low background activity affecting 0.05–0.4% of the cells. Rapamycin induced a rapid recombination, reaching 100% by 48–72 h, with an EC50 of 0.02 nM. Thus, ligand-induced dimerization can efficiently regulate Cre, and should be useful to achieve a tight temporal control of its activity, such as in the case of the creation of conditional knock-out animals. PMID:14576331

  14. Regulation of Cre recombinase by ligand-induced complementation of inactive fragments.

    PubMed

    Jullien, Nicolas; Sampieri, François; Enjalbert, Alain; Herman, Jean-Paul

    2003-11-01

    Cre recombinase is extensively used to engineer the genome of experimental animals. However, its usefulness is still limited by the lack of an efficient temporal control over its activity. To overcome this, we have developed DiCre, a regulatable fragment complementation system for Cre. The enzyme was split into two moieties that were fused to FKBP12 (FK506-binding protein) and FRB (binding domain of the FKBP12-rapamycin-associated protein), respectively. These can be efficiently heterodimerized by rapamycin. Several variants, based on splitting Cre at different sites and using different linker peptides, were tested in an indicator cell line. The fusion proteins, taken separately, had no recombinase activity. Stable transformants, co-expressing complementing fragments based on splitting Cre between Asn59 and Asn60, displayed low background activity affecting 0.05-0.4% of the cells. Rapamycin induced a rapid recombination, reaching 100% by 48-72 h, with an EC50 of 0.02 nM. Thus, ligand-induced dimerization can efficiently regulate Cre, and should be useful to achieve a tight temporal control of its activity, such as in the case of the creation of conditional knock-out animals.

  15. Selective Sirt2 inhibition by ligand-induced rearrangement of the active site.

    PubMed

    Rumpf, Tobias; Schiedel, Matthias; Karaman, Berin; Roessler, Claudia; North, Brian J; Lehotzky, Attila; Oláh, Judit; Ladwein, Kathrin I; Schmidtkunz, Karin; Gajer, Markus; Pannek, Martin; Steegborn, Clemens; Sinclair, David A; Gerhardt, Stefan; Ovádi, Judit; Schutkowski, Mike; Sippl, Wolfgang; Einsle, Oliver; Jung, Manfred

    2015-02-12

    Sirtuins are a highly conserved class of NAD(+)-dependent lysine deacylases. The human isotype Sirt2 has been implicated in the pathogenesis of cancer, inflammation and neurodegeneration, which makes the modulation of Sirt2 activity a promising strategy for pharmaceutical intervention. A rational basis for the development of optimized Sirt2 inhibitors is lacking so far. Here we present high-resolution structures of human Sirt2 in complex with highly selective drug-like inhibitors that show a unique inhibitory mechanism. Potency and the unprecedented Sirt2 selectivity are based on a ligand-induced structural rearrangement of the active site unveiling a yet-unexploited binding pocket. Application of the most potent Sirtuin-rearranging ligand, termed SirReal2, leads to tubulin hyperacetylation in HeLa cells and induces destabilization of the checkpoint protein BubR1, consistent with Sirt2 inhibition in vivo. Our structural insights into this unique mechanism of selective sirtuin inhibition provide the basis for further inhibitor development and selective tools for sirtuin biology.

  16. Local and global synchronization transitions induced by time delays in small-world neuronal networks with chemical synapses.

    PubMed

    Yu, Haitao; Wang, Jiang; Du, Jiwei; Deng, Bin; Wei, Xile

    2015-02-01

    Effects of time delay on the local and global synchronization in small-world neuronal networks with chemical synapses are investigated in this paper. Numerical results show that, for both excitatory and inhibitory coupling types, the information transmission delay can always induce synchronization transitions of spiking neurons in small-world networks. In particular, regions of in-phase and out-of-phase synchronization of connected neurons emerge intermittently as the synaptic delay increases. For excitatory coupling, all transitions to spiking synchronization occur approximately at integer multiples of the firing period of individual neurons; while for inhibitory coupling, these transitions appear at the odd multiples of the half of the firing period of neurons. More importantly, the local synchronization transition is more profound than the global synchronization transition, depending on the type of coupling synapse. For excitatory synapses, the local in-phase synchronization observed for some values of the delay also occur at a global scale; while for inhibitory ones, this synchronization, observed at the local scale, disappears at a global scale. Furthermore, the small-world structure can also affect the phase synchronization of neuronal networks. It is demonstrated that increasing the rewiring probability can always improve the global synchronization of neuronal activity, but has little effect on the local synchronization of neighboring neurons.

  17. A Global View Programming Abstraction for Transitioning MPI Codes to PGAS Languages

    SciTech Connect

    Mintz, Tiffany M; Hernandez, Oscar R; Bernholdt, David E

    2014-01-01

    The multicore generation of scientific high performance computing has provided a platform for the realization of Exascale computing, and has also underscored the need for new paradigms in coding parallel applications. The current standard for writing parallel applications requires programmers to use languages designed for sequential execution. These languages have abstractions that only allow programmers to operate on the process centric local view of data. To provide suitable languages for parallel execution, many research efforts have designed languages based on the Partitioned Global Address Space (PGAS) programming model. Chapel is one of the more recent languages to be developed using this model. Chapel supports multithreaded execution with high-level abstractions for parallelism. With Chapel in mind, we have developed a set of directives that serve as intermediate expressions for transitioning scientific applications from languages designed for sequential execution to PGAS languages like Chapel that are being developed with parallelism in mind.

  18. Evidence for ligand-induced conformational changes in rabbit-muscle glyceraldehyde-3-phosphate dehydrogenase.

    PubMed

    Henis, Y I; Levitzki, A; Gafni, A

    1979-07-01

    The tetrameric glyceraldehyde-3-phosphate dehydrogenase from rabbit muscle binds NAD+ and some of its analogues in a negatively cooperative manner, whereas other NAD+ analogues bind non-cooperatively to this enzyme. Subsequent to alkylation of a fraction of the active sites of the enzyme with the fluorescent SH reagent N-iodoacetyl-N'-(5-sulfo-1-naphthyl)-ethylenediamine, it was found that the alkylated sites bind NAD+ and NAD+ analogues with a markedly reduced affinity as compared with non-alkylated sites. It was therefore feasible to measure the fluorescence and the circular polarization of the luminescence of the enzyme-bound alkyl groups as a function of binding of NAD+ and of NAD+ analogues to the non-alkylated sites. The changes observed indicate that ligand binding to the non-alkylated sites induces changes in the fluorescence properties of the alkyl groups bound to neighbouring subunits, most likely through the protein moiety. The nature of these changes appears to depend on the structure of the coenzyme analogue. The binding of the non-cooperative binders acetyl-pyridine--adenine dinucleotide, ATP and ADP-ribose induce different conformational changes in the neighbouring vacant subunit, as monitored by the spectroscopic properties of the bound alkyl group. These results in conjunction with other data support the view that the negative cooperativity in NAD+ binding to glyceraldehyde-3-phosphate dehydrogenase results from ligand-induced conformational changes. Furthermore, these results further support the view that subtle structural changes in the coenzyme molecule determine the nature of the conformational changes induced within the enzyme tetramer.

  19. Evaluation of Ligand-Inducible Expression Systems for Conditional Neuronal Manipulations of Sleep in Drosophila

    PubMed Central

    Li, Qiuling; Stavropoulos, Nicholas

    2016-01-01

    Drosophila melanogaster is a powerful model organism for dissecting the molecular mechanisms that regulate sleep, and numerous studies in the fly have identified genes that impact sleep–wake cycles. Conditional genetic analysis is essential to distinguish the mechanisms by which these genes impact sleep: some genes might exert their effects developmentally, for instance by directing the assembly of neuronal circuits that regulate sleep; other genes may regulate sleep in adulthood; and yet other genes might influence sleep by both developmental and adult mechanisms. Here we have assessed two ligand-inducible expression systems, Geneswitch and the Q-system, for conditional and neuronally restricted manipulations of sleep in Drosophila. While adult-specific induction of a neuronally expressed Geneswitch transgene (elav-GS) is compatible with studies of sleep as shown previously, developmental induction of elav-GS strongly and nonspecifically perturbs sleep in adults. The alterations of sleep in elav-GS animals occur at low doses of Geneswitch agonist and in the presence of transgenes unrelated to sleep, such as UAS-CD8-GFP. Furthermore, developmental elav-GS induction is toxic and reduces brood size, indicating multiple adverse effects of neuronal Geneswitch activation. In contrast, the transgenes and ligand of the Q-system do not significantly impact sleep–wake cycles when used for constitutive, developmental, or adult-specific neuronal induction. The nonspecific effects of developmental elav-GS activation on sleep indicate that such manipulations require cautious interpretation, and suggest that the Q-system or other strategies may be more suitable for conditional genetic analysis of sleep and other behaviors in Drosophila. PMID:27558667

  20. Dynamical Transitions between Stick-Slip and Steady Motions of Bistable Units with Global and Asymmetric Local Interactions

    NASA Astrophysics Data System (ADS)

    Yamazaki, Yoshihiro

    2017-04-01

    For a system consisting of bistable units with global and asymmetric local interactions, there exist two different types of dynamical transition between stick-slip and steady motions: continuous and discontinuous in the amplitude of stick-slip motion. These two types are consistent with the experimental findings in a dry friction system. The dynamical phase diagram and other types of transition are also discussed.

  1. Sustainable Biofuels A Transitions Approach to Understanding the Global Expansion of Ethanol and Biodiesel

    NASA Astrophysics Data System (ADS)

    Cottes, Jeffrey Jacob

    Between 1998 and 2008, the promise of biofuels to increase rural development, enhance energy security, and reduce greenhouse gas emissions stimulated their diffusion across international markets. This rapid expansion of ethanol and biodiesel encouraged many jurisdictions to implement biofuels expansion policies and programs. Global biofuels, characterised by mass production and international trade of ethanol and biodiesel, occurred despite their long history as marginal technologies on the fringe of the petroleum-based transportation energy regime. The first purpose of this dissertation is to examine the global expansion of ethanol and biodiesel to understand how these recurrent socio-technological failures co-evolved with petroleum transportation fuels. Drawing from the field of socio-technical transitions, this dissertation also assesses the global expansion of ethanol and biodiesel to determine whether or not these first generation biofuels are sustainable. Numerous studies have assessed the technical effects of ethanol and biodiesel, but effects-based technical assessments of transport biofuels are unable to explain the interaction of wider system elements. The configuration of multi-level factors (i.e., niche development, the technological regime, and the socio-technical landscape) informs the present and emerging social functions of biofuels, which become relevant when determining how biofuels might become a sustainable energy option. The biofuels regimes that evolved in Brazil, the United States, and the European Union provide case studies show how ethanol and biodiesel expanded from fringe fuels to global commodities. The production infrastructures within these dominant biofuels regimes contribute to a persistence of unsustainable first generation biofuels that can inhibit the technical development and sustainability of biofuels. However, new and emerging ethanol and biodiesel markets are relatively small in comparison to the dominant regimes, and can

  2. The global gene expression profile of the secondary transition during pancreatic development.

    PubMed

    Willmann, Stefanie J; Mueller, Nikola S; Engert, Silvia; Sterr, Michael; Burtscher, Ingo; Raducanu, Aurelia; Irmler, Martin; Beckers, Johannes; Sass, Steffen; Theis, Fabian J; Lickert, Heiko

    2016-02-01

    Pancreas organogenesis is a highly dynamic process where neighboring tissue interactions lead to dynamic changes in gene regulatory networks that orchestrate endocrine, exocrine, and ductal lineage formation. To understand the spatio-temporal regulatory logic we have used the Forkhead transcription factor Foxa2-Venus fusion (FVF) knock-in reporter mouse to separate the FVF(+) pancreatic epithelium from the FVF(−) surrounding tissue (mesenchyme, neurons, blood, and blood vessels) to perform a genome-wide mRNA expression profiling at embryonic days (E) 12.5-15.5. Annotating genes and molecular processes suggest that FVF marks endoderm-derived multipotent epithelial progenitors at several lineage restriction steps, when the bulk of endocrine, exocrine and ductal cells are formed during the secondary transition. In the pancreatic epithelial compartment, we identified most known endocrine and exocrine lineage determining factors and diabetes-associated genes, but also unknown genes with spatio-temporal regulated pancreatic expression. In the non-endoderm-derived compartment, we identified many well-described regulatory genes that are not yet functionally annotated in pancreas development, emphasizing that neighboring tissue interactions are still ill defined. Pancreatic expression of over 635 genes was analyzed with them RNA in situ hybridization Genepaint public database. This validated the quality of the profiling data set and identified hundreds of genes with spatially restricted expression patterns in the pancreas. Some of these genes are also targeted by pancreatic transcription factors and show active chromatin marks in human islets of Langerhans. Thus, with the highest spatio-temporal resolution of a global gene expression profile during the secondary transition, our study enables to shed light on neighboring tissue interactions, developmental timing and diabetes gene regulation.

  3. Evolutionary Transition from Pathogenicity to Commensalism: Global Regulator Mutations Mediate Fitness Gains through Virulence Attenuation.

    PubMed

    Jansen, Gunther; Crummenerl, Lena L; Gilbert, Felix; Mohr, Timm; Pfefferkorn, Roxana; Thänert, Robert; Rosenstiel, Philip; Schulenburg, Hinrich

    2015-11-01

    Symbiotic interactions are indispensable for metazoan function, but their origin and evolution remain elusive. We use a controlled evolution experiment to demonstrate the emergence of novel commensal interactions between Pseudomonas aeruginosa, an initially pathogenic bacterium, and a metazoan host, Caenorhabditis elegans. We show that commensalism evolves through loss of virulence, because it provides bacteria with a double fitness advantage: Increased within-host fitness and a larger host population to infect. Commensalism arises irrespective of host immune status, as the adaptive path in immunocompromised C. elegans knockouts does not differ from that in wild type. Dissection of temporal dynamics of genomic adaptation for 125 bacterial populations reveals highly parallel evolution of incipient commensalism across independent biological replicates. Adaptation is mainly achieved through frame shift mutations in the global regulator lasR and nonsynonymous point mutations in the polymerase gene rpoB that arise early in evolution. Genetic knockouts of lasR not only corroborate its role in virulence attenuation but also show that further mutations are necessary for the fully commensal phenotype. The evolutionary transition from pathogenicity to commensalism as we observe here is facilitated by mutations in global regulators such as lasR, because few genetic changes cause pleiotropic effects across the genome with large phenotypic effects. Finally, we found that nucleotide diversity increased more quickly in bacteria adapting to immunocompromised hosts than in those adapting to immunocompetent hosts. Nevertheless, the outcome of evolution was comparable across host types. Commensalism can thus evolve independently of host immune state solely as a side-effect of bacterial adaptation to novel hosts.

  4. Evolutionary Transition from Pathogenicity to Commensalism: Global Regulator Mutations Mediate Fitness Gains through Virulence Attenuation

    PubMed Central

    Jansen, Gunther; Crummenerl, Lena L.; Gilbert, Felix; Mohr, Timm; Pfefferkorn, Roxana; Thänert, Robert; Rosenstiel, Philip; Schulenburg, Hinrich

    2015-01-01

    Symbiotic interactions are indispensable for metazoan function, but their origin and evolution remain elusive. We use a controlled evolution experiment to demonstrate the emergence of novel commensal interactions between Pseudomonas aeruginosa, an initially pathogenic bacterium, and a metazoan host, Caenorhabditis elegans. We show that commensalism evolves through loss of virulence, because it provides bacteria with a double fitness advantage: Increased within-host fitness and a larger host population to infect. Commensalism arises irrespective of host immune status, as the adaptive path in immunocompromised C. elegans knockouts does not differ from that in wild type. Dissection of temporal dynamics of genomic adaptation for 125 bacterial populations reveals highly parallel evolution of incipient commensalism across independent biological replicates. Adaptation is mainly achieved through frame shift mutations in the global regulator lasR and nonsynonymous point mutations in the polymerase gene rpoB that arise early in evolution. Genetic knockouts of lasR not only corroborate its role in virulence attenuation but also show that further mutations are necessary for the fully commensal phenotype. The evolutionary transition from pathogenicity to commensalism as we observe here is facilitated by mutations in global regulators such as lasR, because few genetic changes cause pleiotropic effects across the genome with large phenotypic effects. Finally, we found that nucleotide diversity increased more quickly in bacteria adapting to immunocompromised hosts than in those adapting to immunocompetent hosts. Nevertheless, the outcome of evolution was comparable across host types. Commensalism can thus evolve independently of host immune state solely as a side-effect of bacterial adaptation to novel hosts. PMID:26199376

  5. Phase transition and hysteresis loop in structured games with global updating

    NASA Astrophysics Data System (ADS)

    Wang, Wen-Xu; Lü, Jinhu; Chen, Guanrong; Hui, P. M.

    2008-04-01

    We present a global payoff-based strategy updating model for studying cooperative behavior of a networked population. We adopt the Prisoner’s Dilemma game and the snowdrift game as paradigms for characterizing the interactions among individuals. We investigate the model on regular, small-world, and scale-free networks, and find multistable cooperation states depending on the initial cooperator density. In particular for the snowdrift game on small-world and scale-free networks, there exist a discontinuous phase transition and hysteresis loops of cooperator density. We explain the observed properties by theoretical predictions and simulation results of the average number of neighbors of cooperators and defectors, respectively. Our work indicates that individuals with more neighbors have a trend to preserve their initial strategies, which has strong impacts on the strategy updating of individuals with fewer neighbors; while the fact that individuals with few neighbors have to become cooperators to avoid gaining the lowest payoff plays significant roles in maintaining and spreading of cooperation strategy.

  6. Spatial dispersal of bacterial colonies induces a dynamical transition from local to global quorum sensing

    NASA Astrophysics Data System (ADS)

    Yusufaly, Tahir I.; Boedicker, James Q.

    2016-12-01

    Bacteria communicate using external chemical signals called autoinducers (AI) in a process known as quorum sensing (QS). QS efficiency is reduced by both limitations of AI diffusion and potential interference from neighboring strains. There is thus a need for predictive theories of how spatial community structure shapes information processing in complex microbial ecosystems. As a step in this direction, we apply a reaction-diffusion model to study autoinducer signaling dynamics in a single-species community as a function of the spatial distribution of colonies in the system. We predict a dynamical transition between a local quorum sensing (LQS) regime, with the AI signaling dynamics primarily controlled by the local population densities of individual colonies, and a global quorum sensing (GQS) regime, with the dynamics being dependent on collective intercolony diffusive interactions. The crossover between LQS to GQS is intimately connected to a trade-off between the signaling network's latency, or speed of activation, and its throughput, or the total spatial range over which all the components of the system communicate.

  7. Control of retinoic acid receptor heterodimerization by ligand-induced structural transitions. A novel mechanism of action for retinoid antagonists.

    PubMed

    Depoix, C; Delmotte, M H; Formstecher, P; Lefebvre, P

    2001-03-23

    Heterodimerization of retinoic acid receptors (RARs) with 9-cis-retinoic receptors (RXRs) is a prerequisite for binding of RXR.RAR dimers to DNA and for retinoic acid-induced gene regulation. Whether retinoids control RXR/RAR solution interaction remains a debated question, and we have used in vitro and in vivo protein interaction assays to investigate the role of ligand in modulating RXR/RAR interaction in the absence of DNA. Two-hybrid assay in mammalian cells demonstrated that only RAR agonists were able to increase significantly RAR interaction with RXR, whereas RAR antagonists inhibited RXR binding to RAR. Quantitative glutathione S-transferase pull-down assays established that there was a strict correlation between agonist binding affinity for the RAR monomer and the affinity of RXR for liganded RAR, but RAR antagonists were inactive in inducing RXR recruitment to RAR in vitro. Alteration of coactivator- or corepressor-binding interfaces of RXR or RAR did not alter ligand-enhanced dimerization. In contrast, preventing the formation of a stable holoreceptor structure upon agonist binding strongly altered RXR.RAR dimerization. Finally, we observed that RAR interaction with RXR silenced RXR ligand-dependent activation function. We propose that ligand-controlled dimerization of RAR with RXR is an important step in the RXR.RAR activation process. This interaction is dependent upon adequate remodeling of the AF-2 structure and amenable to pharmacological inhibition by structurally modified retinoids.

  8. A Conceptual Framework and Classification for the Fluvial-Backwater-Marine Transition in Coastal Rivers Globally

    NASA Astrophysics Data System (ADS)

    Howes, N. C.; Georgiou, I. Y.; Hughes, Z. J.; Wolinsky, M. A.

    2012-12-01

    Channels in fluvio-deltaic and coastal plain settings undergo a progressive series of downstream transitions in hydrodynamics and sediment transport, which is consequently reflected in their morphology and stratigraphic architecture. Conditions progress from uniform fluvial flow to backwater conditions with non-uniform flow, and finally to bi-directional tidal flow or estuarine circulation at the ocean boundary. While significant attention has been given to geomorphic scaling relationships in purely fluvial settings, there have been far fewer studies on the backwater and tidal reaches, and no systematic comparisons. Our study addresses these gaps by analyzing geometric scaling relationships independently in each of the above hydrodynamic regimes and establishes a comparison. To accomplish this goal we have constructed a database of planform geometries including more than 150 channels. In terms of hydrodynamics studies, much of the work on backwater dynamics has concentrated on the Mississippi River, which has very limited tidal influence. We will extend this analysis to include systems with appreciable offshore tidal range, using a numerical hydrodynamic model to study the interaction between backwater dynamics and tides. The database is comprised of systems with a wide range of tectonic, climatic, and oceanic forcings. The scale of these systems, as measured by bankfull width, ranges over three orders of magnitude from the Amazon River in Brazil to the Palix River in Washington. Channel centerlines are extracted from processed imagery, enabling continuous planform measurements of bankfull width, meander wavelength, and sinuosity. Digital terrain and surface models are used to estimate floodplain slopes. Downstream tidal boundary conditions are obtained from the TOPEX 7.1 global tidal model, while upstream boundary conditions such as basin area, relief, and discharge are obtained by linking the databases of Milliman and Meade (2011) and Syvitski (2005). Backwater

  9. Ligand-induced folding of the thiM TPP riboswitch investigated by a structure-based fluorescence spectroscopic approach

    PubMed Central

    Lang, Kathrin; Rieder, Renate; Micura, Ronald

    2007-01-01

    Riboswitches are genetic control elements within non-coding regions of mRNA. They consist of a metabolite-sensitive aptamer and an adjoining expression platform. Here, we describe ligand-induced folding of a thiamine pyrophosphate (TPP) responsive riboswitch from Escherichia coli thiM mRNA, using chemically labeled variants. Referring to a recent structure determination of the TPP/aptamer complex, each variant was synthesized with a single 2-aminopurine (AP) nucleobase replacement that was selected to monitor formation of tertiary interactions of a particular region during ligand binding in real time by fluorescence experiments. We have determined the rate constants for conformational adjustment of the individual AP sensors. From the 7-fold differentiation of these constants, it can be deduced that tertiary contacts between the two parallel helical domains (P2/J3-2/P3/L3 and P4/P5/L5) that grip the ligand's ends in two separate pockets, form significantly faster than the function-critical three-way junction with stem P1 fully developed. Based on these data, we characterize the process of ligand binding by an induced fit of the RNA and propose a folding model of the TPP riboswitch aptamer. For the full-length riboswitch domain and for shorter constructs that represent transcriptional intermediates, we have additionally evaluated ligand-induced folding via AP-modified variants and provide insights into the sequential folding pathway that involves a finely balanced equilibrium of secondary structures. PMID:17693433

  10. Running Out of and Into Oil: Analyzing Global Oil Depletion and Transition Through 2050

    SciTech Connect

    Greene, D.L.

    2003-11-14

    This report presents a risk analysis of world conventional oil resource production, depletion, expansion, and a possible transition to unconventional oil resources such as oil sands, heavy oil and shale oil over the period 2000 to 2050. Risk analysis uses Monte Carlo simulation methods to produce a probability distribution of outcomes rather than a single value. Probability distributions are produced for the year in which conventional oil production peaks for the world as a whole and the year of peak production from regions outside the Middle East. Recent estimates of world oil resources by the United States Geological Survey (USGS), the International Institute of Applied Systems Analysis (IIASA), the World Energy Council (WEC) and Dr. C. Campbell provide alternative views of the extent of ultimate world oil resources. A model of oil resource depletion and expansion for twelve world regions is combined with a market equilibrium model of conventional and unconventional oil supply and demand to create a World Energy Scenarios Model (WESM). The model does not make use of Hubbert curves but instead relies on target reserve-to-production ratios to determine when regional output will begin to decline. The authors believe that their analysis has a bias toward optimism about oil resource availability because it does not attempt to incorporate political or environmental constraints on production, nor does it explicitly include geologic constraints on production rates. Global energy scenarios created by IIASA and WEC provide the context for the risk analysis. Key variables such as the quantity of undiscovered oil and rates of technological progress are treated as probability distributions, rather than constants. Analyses based on the USGS and IIASA resource assessments indicate that conventional oil production outside the Middle East is likely to peak sometime between 2010 and 2030. The most important determinants of the date are the quantity of undiscovered oil, the rate at

  11. Transition.

    ERIC Educational Resources Information Center

    Thompson, Sandy, Ed.; And Others

    1990-01-01

    This "feature issue" focuses on transition from school to adult life for persons with disabilities. Included are "success stories," brief program descriptions, and a list of resources. Individual articles include the following titles and authors: "Transition: An Energizing Concept" (Paul Bates); "Transition…

  12. The Global Epidemiologic Transition: Noncommunicable Diseases and Emerging Health Risk of Allergic Disease in Sub-Saharan Africa.

    PubMed

    Atiim, George A; Elliott, Susan J

    2016-04-01

    Globally, there has been a shift in the causes of illness and death from infectious diseases to noncommunicable diseases. This changing pattern has been attributed to the effects of an (ongoing) epidemiologic transition. Although researchers have applied epidemiologic transition theory to questions of global health, there have been relatively few studies exploring its relevance especially in the context of emerging allergic disorders in sub-Saharan Africa (SSA). In this article, we address the growing burden of noncommunicable diseases in sub-Saharan Africa through the lens of epidemiologic transition theory. After a brief review of the literature on the evolution of the epidemiologic transition with a particular emphasis on sub-Saharan Africa, we discuss existing frameworks designed to help inform our understanding of changing health trends in the developing world. We subsequently propose a framework that privileges "place" as a key construct informing our understanding. In so doing, we use the example of allergic disease, one of the fastest growing chronic conditions in most parts of the world.

  13. Global Conceptualization of the Professional Learning Community Process: Transitioning from Country Perspectives to International Commonalities

    ERIC Educational Resources Information Center

    Huffman, Jane B.; Olivier, Dianne F.; Wang, Ting; Chen, Peiying; Hairon, Salleh; Pang, Nicholas

    2016-01-01

    The authors seek to find common PLC structures and actions among global educational systems to enhance understanding and practice. Six international researchers formed the Global Professional Learning Community Network (GloPLCNet), conducted literature reviews of each country's involvement with PLC actions, and noted similarities and common…

  14. A Global Model Simulation of Aerosol Effects of Surface Radiation Budget- Toward Understanding of the "Dimming to Brightening" Transition

    NASA Technical Reports Server (NTRS)

    Chin, Mian; Diehl, Thomas; Bian, Huisheng; Yu, Hongbin

    2008-01-01

    We present a global model study on the role aerosols play in the change of solar radiation at Earth's surface that transitioned from a decreasing (dimming) trend to an increasing (brightening) trend. Our primary objective is to understand the relationship between the long-term trends of aerosol emission, atmospheric burden, and surface solar radiation. More specifically, we use the recently compiled comprehensive global emission datasets of aerosols and precursors from fuel combustion, biomass burning, volcanic eruptions and other sources from 1980 to 2006 to simulate long-term variations of aerosol distributions and optical properties, and then calculate the multi-decadal changes of short-wave radiative fluxes at the surface and at the top of the atmosphere by coupling the GOCART model simulated aerosols with the Goddard radiative transfer model. The model results are compared with long-term observational records from ground-based networks and satellite data. We will address the following critical questions: To what extent can the observed surface solar radiation trends, known as the transition from dimming to brightening, be explained by the changes of anthropogenic and natural aerosol loading on global and regional scales? What are the relative contributions of local emission and long-range transport to the surface radiation budget and how do these contributions change with time?

  15. Ligand-Induced Asymmetry in Histidine Sensor Kinase Complex Regulates Quorum Sensing

    SciTech Connect

    Neiditch,M.; Federle, M.; Pompeani, A.; Kelly, R.; Swem, D.; Jeffrey, P.; Bassler, B.; Hughson, F.

    2006-01-01

    Bacteria sense their environment using receptors of the histidine sensor kinase family, but how kinase activity is regulated by ligand binding is not well understood. Autoinducer-2 (AI-2), a secreted signaling molecule originally identified in studies of the marine bacterium Vibrio harveyi, regulates quorum-sensing responses and allows communication between different bacterial species. AI-2 signal transduction in V. harveyi requires the integral membrane receptor LuxPQ, comprised of periplasmic binding protein (LuxP) and histidine sensor kinase (LuxQ) subunits. Combined X-ray crystallographic and functional studies show that AI-2 binding causes a major conformational change within LuxP, which in turn stabilizes a quaternary arrangement in which two LuxPQ monomers are asymmetrically associated. We propose that formation of this asymmetric quaternary structure is responsible for repressing the kinase activity of both LuxQ subunits and triggering the transition of V. harveyi into quorum-sensing mode.

  16. Finite-size-induced transitions to synchrony in oscillator ensembles with nonlinear global coupling.

    PubMed

    Komarov, Maxim; Pikovsky, Arkady

    2015-08-01

    We report on finite-sized-induced transitions to synchrony in a population of phase oscillators coupled via a nonlinear mean field, which microscopically is equivalent to a hypernetwork organization of interactions. Using a self-consistent approach and direct numerical simulations, we argue that a transition to synchrony occurs only for finite-size ensembles and disappears in the thermodynamic limit. For all considered setups, which include purely deterministic oscillators with or without heterogeneity in natural oscillatory frequencies, and an ensemble of noise-driven identical oscillators, we establish scaling relations describing the order parameter as a function of the coupling constant and the system size.

  17. State-and-transition model archetypes: a global taxonomy of rangeland change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    State and transition models (STMs) synthesize science-based and local knowledge to formally represent the dynamics of rangeland and other ecosystems. Mental models or concepts of ecosystem dynamics implicitly underlie all management decisions in rangelands and thus how people influence rangeland sus...

  18. HAT-South: A Global Network of Southern Hemisphere Automated Telescopes to Detect Transiting Exoplanets

    NASA Astrophysics Data System (ADS)

    Bakos, G.; Afonso, C.; Henning, T.; Jordán, A.; Holman, M.; Noyes, R. W.; Sackett, P. D.; Sasselov, D.; Kovács, Gábor; Csubry, Z.; Pál, A.

    2009-02-01

    HAT-South is a network of six identical, fully automated wide field telescopes, to be located at three sites (Chile: Las Campanas, Australia: Siding Springs, and Namibia: HESS site) in the Southern hemisphere. The primary purpose of the network is to detect and characterize a large number of extra-solar planets transiting nearby bright stars, and to explore their diversity. Operation of HAT-South is a collaboration among the Harvard-Smithsonian Center for Astrophysics (CfA), Max Planck Institute for Astronomy (MPIA) and the Australian National University (ANU). The network is expected to be ready for initial science operations in 2009. The three sites will permit near round-the-clock monitoring of selected fields, and the continuous data-stream will greatly enhance recovery of transits. HAT-South will be sensitive to planetary transits down to R≈14 across a 128 square-degrees combined field of view, thereby targeting a large number of dwarfs with feasible confirmation-mode follow-up. We anticipate a yearly detection rate of approximately 25 planets transiting bright stars.

  19. Running Out Of and Into Oil. Analyzing Global Oil Depletion and Transition Through 2050

    SciTech Connect

    Greene, David L.; Hopson, Janet L.; Li, Jia

    2003-10-01

    This report presents a risk analysis of world conventional oil resource production, depletion, expansion, and a possible transition to unconventional oil resources such as oil sands, heavy oil and shale oil over the period 2000 to 2050. Risk analysis uses Monte Carlo simulation methods to produce a probability distribution of outcomes rather than a single value.

  20. Education in Countries in Transition Facing Globalization--A Case Study Croatia

    ERIC Educational Resources Information Center

    Slaus, Ivo; Slaus-Kokotovic, Andrea; Morovic, Jasenka

    2004-01-01

    The status of the educational system of Croatia is presented and several human development indicators for Croatia are compared with those of other countries in transition. The role of education in facing globalisation and in assuring sustainable development is analysed. The aims of various levels of education: primary, secondary and higher…

  1. The Application of Global Kinetic Models to HMX Beta-Delta Transition and Cookoff Processes

    SciTech Connect

    Wemhoff, A P; Burnham, A K; Nichols III, A L

    2006-12-07

    The reduction of the number of reactions in kinetic models for both the HMX beta-delta phase transition and thermal cookoff provides an attractive alternative to traditional multi-stage kinetic models due to reduced calibration effort requirements. In this study, we use the LLNL code ALE3D to provide calibrated kinetic parameters for a two-reaction bidirectional beta-delta HMX phase transition model based on Sandia Instrumented Thermal Ignition (SITI) and Scaled Thermal Explosion (STEX) temperature history curves, and a Prout-Tompkins cookoff model based on One-Dimensional Time to Explosion (ODTX) data. Results show that the two-reaction bidirectional beta-delta transition model presented here agrees as well with STEX and SITI temperature history curves as a reversible four-reaction Arrhenius model, yet requires an order of magnitude less computational effort. In addition, a single-reaction Prout-Tompkins model calibrated to ODTX data provides better agreement with ODTX data than a traditional multi-step Arrhenius model, and can contain up to 90% less chemistry-limited time steps for low-temperature ODTX simulations. Manual calibration methods for the Prout-Tompkins kinetics provide much better agreement with ODTX experimental data than parameters derived from Differential Scanning Calorimetry (DSC) measurements at atmospheric pressure. The predicted surface temperature at explosion for STEX cookoff simulations is a weak function of the cookoff model used, and a reduction of up to 15% of chemistry-limited time steps can be achieved by neglecting the beta-delta transition for this type of simulation. Finally, the inclusion of the beta-delta transition model in the overall kinetics model can affect the predicted time to explosion by 1% for the traditional multi-step Arrhenius approach, while up to 11% using a Prout-Tompkins cookoff model.

  2. Theoretical Analysis of Fas Ligand-Induced Apoptosis with an Ordinary Differential Equation Model.

    PubMed

    Shi, Zhimin; Li, Yan; Liu, Zhihai; Mi, Jun; Wang, Renxiao

    2012-12-01

    Upon the treatment of Fas ligand, different types of cells exhibit different apoptotic mechanisms, which are determined by a complex network of biological pathways. In order to derive a quantitative interpretation of the cell sensitivity and apoptosis pathways, we have developed an ordinary differential equation model. Our model is intended to include all of the known major components in apoptosis pathways mediated by Fas receptor. It is composed of 29 equations using a total of 49 rate constants and 13 protein concentrations. All parameters used in our model were derived through nonlinear fitting to experimentally measured concentrations of four selected proteins in Jurkat T-cells, including caspase-3, caspase-8, caspase-9, and Bid. Our model is able to correctly interpret the role of kinetic parameters and protein concentrations in cell sensitivity to FasL. It reveals the possible reasons for the transition between type-I and type-II pathways and also provides some interesting predictions, such as the more decisive role of Fas over Bax in apoptosis pathway and a possible feedback mechanism between type-I and type-II pathways. But our model failed in predicting FasL-induced apoptotic mechanism of NCI-60 cells from their gene-expression levels. Limitations in our model are also discussed.

  3. Strike-Slip Faulting Processes on Ganymede: Global Morphological Mapping and Structural Interpretation of Grooved and Transitional Terrains

    NASA Astrophysics Data System (ADS)

    Burkhard, L. M.; Cameron, M. E.; Smith-Konter, B. R.; Seifert, F.; Pappalardo, R. T.; Collins, G. C.

    2015-12-01

    Ganymede's fractured surface reveals many large-scale, morphologically distinct regions of inferred distributed shear and strike-slip faulting that may be important to the structural development of its surface and in the transition from dark to light (grooved) materials. To better understand the role of strike-slip tectonism in shaping Ganymede's complex icy surface, we perform a detailed mapping of key examples of strike-slip morphologies (i.e., en echelon structures, strike-slip duplexes, laterally offset pre-existing features, and possible strained craters) from Galileo and Voyager images. We focus on complex structures associated with grooved terrain (e.g. Nun Sulcus, Dardanus Sulcus, Tiamat Sulcus, and Arbela Sulcus) and terrains transitional from dark to light terrain (e.g. the boundary between Nippur Sulcus and Marius Regio, including Byblus Sulcus and Philus Sulcus). Detailed structural interpretations suggest strong evidence of strike-slip faulting in some regions (i.e., Nun and Dardanus Sulcus); however, further investigation of additional strike-slip structures is required of less convincing regions (i.e., Byblus Sulcus). Where applicable, these results are synthesized into a global database representing an inferred sense of shear for many of Ganymede's fractures. Moreover, when combined with existing observations of extensional features, these results help to narrow down the range of possible principal stress directions that could have acted at the regional or global scale to produce grooved terrain on Ganymede.

  4. Superuniversality of topological quantum phase transition and global phase diagram of dirty topological systems in three dimensions

    NASA Astrophysics Data System (ADS)

    Goswami, Pallab; Chakravarty, Sudip

    2017-02-01

    The quantum phase transition between two clean, noninteracting topologically distinct gapped states in three dimensions is governed by a massless Dirac fermion fixed point, irrespective of the underlying symmetry class, and this constitutes a remarkably simple example of superuniversality. For a sufficiently weak disorder strength, we show that the massless Dirac fixed point is at the heart of the robustness of superuniversality. We establish this by considering both perturbative and nonperturbative effects of disorder. The superuniversality breaks down at a critical strength of disorder, beyond which the topologically distinct localized phases become separated by a delocalized diffusive phase. In the global phase diagram, the disorder controlled fixed point where superuniversality is lost, serves as a multicritical point, where the delocalized diffusive and two topologically distinct localized phases meet and the nature of the localization-delocalization transition depends on the underlying symmetry class. Based on these features, we construct the global phase diagrams of noninteracting, dirty topological systems in three dimensions. We also establish a similar structure of the phase diagram and the superuniversality for weak disorder in higher spatial dimensions. By noting that 1 /r2 power-law correlated disorder acts as a marginal perturbation for massless Dirac fermions in any spatial dimension d , we have established a general renormalization group framework for addressing disorder driven critical phenomena for fixed spatial dimension d >2 .

  5. From Cutlass to Agribusiness: Caribbean Food and Agriculture in Transition within a Global System.

    ERIC Educational Resources Information Center

    Moran, Michael J.

    This examination of the future role of food and agriculture in world peace and prosperity presents a regional cross-country view of the Caribbean countries with emphasis on the Caricom English speaking countries within a global food system environment. Following an introductory section, the second of six sections focuses on two broad agricultural…

  6. Wave climate, sediment supply and the depth of the sand-mud transition: A global survey

    USGS Publications Warehouse

    George, D.A.; Hill, P.S.

    2008-01-01

    The influences of wave climate and sediment supply on the depths of sand-mud transitions (hSMT) are investigated. Depths of sand-mud transitions (SMT) are based on published granulometric data from surface samples gathered from 14 sites in different wave-dominated coastal environments with fluvial input, including high energy (Columbia, Eel, Russian, San Lorenzo, Copper, and Nepean rivers), moderate energy (Ebro, Nile, Santa Clara, Tseng-wen and Kao-ping rivers), and low energy (Po, Pescara and Tronto rivers) regimes. Geometric mean diameter (GMD) and mud percent are compiled from samples along shore-normal transects, and significant correlation is found between these two textural descriptors. Nominally, the SMT is defined as the transition from GMD > 63????m to 25% mud. This dual definition is applied to the 14 systems, and hSMT is tabulated for each system. Correlation is found between hSMT and the depth at which wave-induced bottom shear stress equals the critical erosion shear stress of the largest mud particles and also between hSMT and significant wave height. Lack of correlation between hSMT and sediment load of nearby rivers indicates either that the influence of sediment supply on depth of the sand-mud transition is small or is not adequately represented in this study. Shelf width and slope do not correlate with residuals from a formalized linear relationship between hSMT and significant wave height. The relationship between hSMT and wave climate is useful for calibration of numerical models of erosion and deposition in wave-dominated coastal environments, for prediction of seabed properties in remote or inaccessible areas, and for reconstruction of paleodepth based on facies changes from sand to mud in ancient rocks. ?? 2008.

  7. Ion intercalation into two-dimensional transition-metal carbides: global screening for new high-capacity battery materials.

    PubMed

    Eames, Christopher; Islam, M Saiful

    2014-11-19

    Two-dimensional transition metal carbides (termed MXenes) are a new family of compounds generating considerable interest due to their unique properties and potential applications. Intercalation of ions into MXenes has recently been demonstrated with good electrochemical performance, making them viable electrode materials for rechargeable batteries. Here we have performed global screening of the capacity and voltage for a variety of intercalation ions (Li(+), Na(+), K(+), and Mg(2+)) into a large number of M2C-based compounds (M = Sc, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta) with F-, H-, O-, and OH-functionalized surfaces using density functional theory methods. In terms of gravimetric capacity a greater amount of Li(+) or Mg(2+) can be intercalated into an MXene than Na(+) or K(+), which is related to the size of the intercalating ion. Variation of the surface functional group and transition metal species can significantly affect the voltage and capacity of an MXene, with oxygen termination leading to the highest capacity. The most promising group of M2C materials in terms of anode voltage and gravimetric capacity (>400 mAh/g) are compounds containing light transition metals (e.g., Sc, Ti, V, and Cr) with nonfunctionalized or O-terminated surfaces. The results presented here provide valuable insights into exploring a rich variety of high-capacity MXenes for potential battery applications.

  8. Ligand-induced structural changes in the cyclic nucleotide-modulated potassium channel MloK1

    NASA Astrophysics Data System (ADS)

    Kowal, Julia; Chami, Mohamed; Baumgartner, Paul; Arheit, Marcel; Chiu, Po-Lin; Rangl, Martina; Scheuring, Simon; Schröder, Gunnar F.; Nimigean, Crina M.; Stahlberg, Henning

    2014-01-01

    Cyclic nucleotide-modulated ion channels are important for signal transduction and pacemaking in eukaryotes. The molecular determinants of ligand gating in these channels are still unknown, mainly because of a lack of direct structural information. Here we report ligand-induced conformational changes in full-length MloK1, a cyclic nucleotide-modulated potassium channel from the bacterium Mesorhizobium loti, analysed by electron crystallography and atomic force microscopy. Upon cAMP binding, the cyclic nucleotide-binding domains move vertically towards the membrane, and directly contact the S1-S4 voltage sensor domains. This is accompanied by a significant shift and tilt of the voltage sensor domain helices. In both states, the inner pore-lining helices are in an ‘open’ conformation. We propose a mechanism in which ligand binding can favour pore opening via a direct interaction between the cyclic nucleotide-binding domains and voltage sensors. This offers a simple mechanistic hypothesis for the coupling between ligand gating and voltage sensing in eukaryotic HCN channels.

  9. Modelling the Interaction of Catecholamines with the α1A Adrenoceptor Towards a Ligand-induced Receptor Structure

    NASA Astrophysics Data System (ADS)

    Kinsella, Gemma K.; Rozas, Isabel; Watson, Graeme W.

    2005-06-01

    Adrenoceptors are members of the important G protein coupled receptor family for which the detailed mechanism of activation remains unclear. In this study, we have combined docking and molecular dynamics simulations to model the ligand induced effect on an homology derived human α1A adrenoceptor. Analysis of agonist/α1A adrenoceptor complex interactions focused on the role of the charged amine group, the aromatic ring, the N-methyl group of adrenaline, the beta hydroxyl group and the catechol meta and para hydroxyl groups of the catecholamines. The most critical interactions for the binding of the agonists are consistent with many earlier reports and our study suggests new residues possibly involved in the agonist-binding site, namely Thr-174 and Cys-176. We further observe a number of structural changes that occur upon agonist binding including a movement of TM-V away from TM-III and a change in the interactions of Asp-123 of the conserved DRY motif. This may cause Arg-124 to move out of the TM helical bundle and change the orientation of residues in IC-II and IC-III, allowing for increased affinity of coupling to the G-protein.

  10. Ligand-induced structural changes in the cyclic nucleotide-modulated potassium channel MloK1

    PubMed Central

    Kowal, Julia; Chami, Mohamed; Baumgartner, Paul; Arheit, Marcel; Chiu, Po-Lin; Rangl, Martina; Scheuring, Simon; Schröder, Gunnar F.; Nimigean, Crina M.; Stahlberg, Henning

    2014-01-01

    Cyclic nucleotide-modulated ion channels are important for signal transduction and pacemaking in eukaryotes. The molecular determinants of ligand gating in these channels are still unknown, mainly because of a lack of direct structural information. Here we report ligand-induced conformational changes in full-length MloK1, a cyclic nucleotide-modulated potassium channel from the bacterium Mesorhizobium loti, analysed by electron crystallography and atomic force microscopy. Upon cAMP binding, the cyclic nucleotide-binding domains move vertically towards the membrane, and directly contact the S1–S4 voltage sensor domains. This is accompanied by a significant shift and tilt of the voltage sensor domain helices. In both states, the inner pore-lining helices are in an ‘open’ conformation. We propose a mechanism in which ligand binding can favour pore opening via a direct interaction between the cyclic nucleotide-binding domains and voltage sensors. This offers a simple mechanistic hypothesis for the coupling between ligand gating and voltage sensing in eukaryotic HCN channels. PMID:24469021

  11. Ligand-induced IFN gamma receptor tyrosine phosphorylation couples the receptor to its signal transduction system (p91).

    PubMed Central

    Greenlund, A C; Farrar, M A; Viviano, B L; Schreiber, R D

    1994-01-01

    Herein we report that interferon-gamma (IFN gamma) induces the rapid and reversible tyrosine phosphorylation of the IFN gamma receptor. Using a panel of receptor intracellular domain mutants, we show that a membrane-proximal LPKS sequence (residues 266-269) is required for ligand-induced tyrosine kinase activation and/or kinase-receptor association and biological responsiveness, and a functionally critical membrane-distal tyrosine residue (Y440) is a target of the activated enzyme. The biological significance of Y440 phosphorylation was demonstrated by showing that a receptor-derived nonapeptide corresponding to receptor residues 436-444 and containing phosphorylated Y440 bound specifically to p91, blocked p91 phosphorylation and inhibited the generation of an active p91-containing transcription factor complex. In contrast, nonphosphorylated wild-type, phosphorylated mutant, or phosphorylated irrelevant peptides did not. Moreover, the phosphorylated Y440-containing peptide did not interact with a related but distinct latent transcription factor (p113) which is activatible by IFN alpha but not IFN gamma. These results thus document the specific and inducible association of p91 with the phosphorylated IFN gamma receptor and thereby elucidate the mechanism by which ligand couples the IFN gamma receptor to its signal transduction system. Images PMID:8156998

  12. Transitions

    NASA Technical Reports Server (NTRS)

    2006-01-01

    26 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a variety of textures observed on a dust-covered plain in the Marte Valles region of Mars. Textural variations across the scene include: areas that are littered with small impact craters, a channel-like feature that is dominated by mounds of a variety of sizes, small ripples and/or ridges, and relatively smooth, unremarkable terrain. The contact between the cratered plain and the area dominated by mounds marks one of the banks along the edge of one of the shallow valleys of the Marte Valles system.

    Location near: 17.7oN, 175.0oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

  13. Boundary-layer transition and global skin friction measurement with an oil-fringe imaging technique

    NASA Technical Reports Server (NTRS)

    Monson, Daryl J.; Mateer, George G.; Menter, Florian R.

    1993-01-01

    A new oil-fringe imaging system skin friction (FISF) technique to measure skin friction on wind tunnel models is presented. In the method used to demonstrate the technique, lines of oil are applied on surfaces that connect the intended sets of measurement points, and then a wind tunnel is run so that the oil thins and forms interference fringes that are spaced in proportion to local skin friction. After a run the fringe spacings are imaged with a CCD-array digital camera and measured on a computer. Skin friction and transition measurements on a two-dimensional wing are presented and compared with computational predictions.

  14. Does Global Astrocytic Calcium Signaling Participate in Awake Brain State Transitions and Neuronal Circuit Function?

    PubMed

    Kjaerby, Celia; Rasmussen, Rune; Andersen, Mie; Nedergaard, Maiken

    2017-02-16

    We continuously need to adapt to changing conditions within our surrounding environment, and our brain needs to quickly shift between resting and working activity states in order to allow appropriate behaviors. These global state shifts are intimately linked to the brain-wide release of the neuromodulators, noradrenaline and acetylcholine. Astrocytes have emerged as a new player participating in the regulation of brain activity, and have recently been implicated in brain state shifts. Astrocytes display global Ca(2+) signaling in response to activation of the noradrenergic system, but whether astrocytic Ca(2+) signaling is causative or correlative for shifts in brain state and neural activity patterns is not known. Here we review the current available literature on astrocytic Ca(2+) signaling in awake animals in order to explore the role of astrocytic signaling in brain state shifts. Furthermore, we look at the development and availability of innovative new methodological tools that are opening up for new ways of visualizing and perturbing astrocyte activity in awake behaving animals. With these new tools at hand, the field of astrocyte research will likely be able to elucidate the causal and mechanistic roles of astrocytes in complex behaviors within a very near future.

  15. The Global HIV Archive: Facilitating the Transition from Science to Practice of Efficacious HIV Prevention Interventions*

    PubMed Central

    Card, Josefina J.; Newman, Emily N.; Golden, Rachel E.; Kuhn, Tamara; Lomonaco, Carmela

    2014-01-01

    This paper describes the development, content, and capabilities of the online Global HIV Archive (GHA). With the goal of facilitating widespread adaptation and appropriate use of efficacious HIV prevention programs throughout the globe, GHA has: first, expanded and updated the search for HIV prevention programs originating in low-resource countries; second, identified those meritorious HIV prevention programs meeting established efficacy criteria of technical merit, replicability, and positive outcomes; third, prepared both implementation and evaluation materials from the efficacious programs for public use; fourth, developed interactive wizards or capacity-building tools to facilitate appropriate program selection, implementation, and adaptation; and, fifth, made the efficacious programs and accompanying wizards available to health practitioners throughout the globe in both printed and online formats. PMID:24563820

  16. Temporal Global Changes in Gene Expression during Temperature Transition in Yersinia pestis

    PubMed Central

    Motin, Vladimir L.; Georgescu, Anca M.; Fitch, Joseph P.; Gu, Pauline P.; Nelson, David O.; Mabery, Shalini L.; Garnham, Janine B.; Sokhansanj, Bahrad A.; Ott, Linda L.; Coleman, Matthew A.; Elliott, Jeffrey M.; Kegelmeyer, Laura M.; Wyrobek, Andrew J.; Slezak, Thomas R.; Brubaker, Robert R.; Garcia, Emilio

    2004-01-01

    DNA microarrays encompassing the entire genome of Yersinia pestis were used to characterize global regulatory changes during steady-state vegetative growth occurring after shift from 26 to 37°C in the presence and absence of Ca2+. Transcriptional profiles revealed that 51, 4, and 13 respective genes and open reading frames (ORFs) on pCD, pPCP, and pMT were thermoinduced and that the majority of these genes carried by pCD were downregulated by Ca2+. In contrast, Ca2+ had little effect on chromosomal genes and ORFs, of which 235 were thermally upregulated and 274 were thermally downregulated. The primary consequence of these regulatory events is profligate catabolism of numerous metabolites available in the mammalian host. PMID:15342600

  17. Temporal global changes in gene expression during temperature transition in Yersinia pestis.

    PubMed

    Motin, Vladimir L; Georgescu, Anca M; Fitch, Joseph P; Gu, Pauline P; Nelson, David O; Mabery, Shalini L; Garnham, Janine B; Sokhansanj, Bahrad A; Ott, Linda L; Coleman, Matthew A; Elliott, Jeffrey M; Kegelmeyer, Laura M; Wyrobek, Andrew J; Slezak, Thomas R; Brubaker, Robert R; Garcia, Emilio

    2004-09-01

    DNA microarrays encompassing the entire genome of Yersinia pestis were used to characterize global regulatory changes during steady-state vegetative growth occurring after shift from 26 to 37 degrees C in the presence and absence of Ca2+. Transcriptional profiles revealed that 51, 4, and 13 respective genes and open reading frames (ORFs) on pCD, pPCP, and pMT were thermoinduced and that the majority of these genes carried by pCD were downregulated by Ca2+. In contrast, Ca2+ had little effect on chromosomal genes and ORFs, of which 235 were thermally upregulated and 274 were thermally downregulated. The primary consequence of these regulatory events is profligate catabolism of numerous metabolites available in the mammalian host.

  18. Global force-torque phase diagram for the DNA double helix: structural transitions, triple points and collapsed plectonemes

    PubMed Central

    Marko, John F.; Neukirch, Sébastien

    2014-01-01

    We present a free energy model for structural transitions of the DNA double helix driven by tensile and torsional stress. Our model is coarse grained, and is based on semiflexible polymer descriptions of B-DNA, underwound L-DNA, and highly overwound P-DNA. The statistical-mechanical model of plectonemic supercoiling previously developed for B-DNA is applied to semiflexible polymer models of P and L-DNA, to obtain a model of DNA structural transitions in quantitative accord with experiment. We identify two distinct plectonemic states, one “inflated” by electrostatic repulsion and thermal fluctuations, and the other “collapsed”, with the two double helices inside the supercoils driven to close contact. We find that supercoiled B and L are stable only in inflated form, while supercoiled P is always collapsed. We also predict the behavior and experimental signatures of highly underwound “Q”-DNA, the left-handed analog of P-DNA; as for P, supercoiled Q is always collapsed. Overstretched “S”-DNA and strand-separated “stress-melted” DNA are also included in our model, allowing prediction of a global phase diagram for forces up to 1000 pN and torques between ±60 pN nm, or in terms of linking number density, from σ = −5 to +3. PMID:24483501

  19. Global force-torque phase diagram for the DNA double helix: Structural transitions, triple points, and collapsed plectonemes

    NASA Astrophysics Data System (ADS)

    Marko, John F.; Neukirch, Sébastien

    2013-12-01

    We present a free energy model for structural transitions of the DNA double helix driven by tensile and torsional stress. Our model is coarse grained and is based on semiflexible polymer descriptions of B-DNA, underwound L-DNA, and highly overwound P-DNA. The statistical-mechanical model of plectonemic supercoiling previously developed for B-DNA is applied to semiflexible polymer models of P- and L-DNA to obtain a model of DNA structural transitions in quantitative accord with experiment. We identify two distinct plectonemic states, one "inflated" by electrostatic repulsion and thermal fluctuations and the other "collapsed," with the two double helices inside the supercoils driven to close contact. We find that supercoiled B and L are stable only in the inflated form, while supercoiled P is always collapsed. We also predict the behavior and experimental signatures of highly underwound "Q"-DNA, the left-handed analog of P-DNA; as for P, supercoiled Q is always collapsed. Overstretched "S"-DNA and strand-separated "stress-melted" DNA are also included in our model, allowing prediction of a global phase diagram for forces up to 1000 pN and torques between ±60 pN nm, or, in terms of linking number density, from σ =-5 to +3.

  20. The Hetu'u Global Network: Measuring the Distance to the Sun with the Transit of Venus

    NASA Astrophysics Data System (ADS)

    Rodriguez, David; Faherty, J.

    2013-01-01

    In the spirit of historic astronomical endeavors, we invited school groups across the globe to collaborate in a solar distance measurement using the 2012 transit of Venus. In total, our group (stationed at Easter Island, Chile) recruited 19 school groups spread over 6 continents and 10 countries to participate in our Hetu’u Global Network. Applying the methods of French astronomer Joseph-Nicolas Delisle, we used individual second and third Venus-Sun contact times to calculate the distance to the Sun. Ten of the sites in our network had amiable weather; 8 of which measured second contact and 5 of which measured third contact leading to consistent solar distance measurements of 152+/-30 million km and 163+/-30 million km respectively. The distance to the Sun at the time of the transit was 152.25 million km; therefore, our measurements are also consistent within 1-sigma of the known value. The goal of our international school group network was to inspire the next generation of scientists using the excitement and accessibility of such a rare astronomical event. In the process, we connected hundreds of participating students representing a diverse, multi-cultural group with differing political, economic, and racial backgrounds.

  1. Global force-torque phase diagram for the DNA double helix: structural transitions, triple points, and collapsed plectonemes.

    PubMed

    Marko, John F; Neukirch, Sébastien

    2013-12-01

    We present a free energy model for structural transitions of the DNA double helix driven by tensile and torsional stress. Our model is coarse grained and is based on semiflexible polymer descriptions of B-DNA, underwound L-DNA, and highly overwound P-DNA. The statistical-mechanical model of plectonemic supercoiling previously developed for B-DNA is applied to semiflexible polymer models of P- and L-DNA to obtain a model of DNA structural transitions in quantitative accord with experiment. We identify two distinct plectonemic states, one "inflated" by electrostatic repulsion and thermal fluctuations and the other "collapsed," with the two double helices inside the supercoils driven to close contact. We find that supercoiled B and L are stable only in the inflated form, while supercoiled P is always collapsed. We also predict the behavior and experimental signatures of highly underwound "Q"-DNA, the left-handed analog of P-DNA; as for P, supercoiled Q is always collapsed. Overstretched "S"-DNA and strand-separated "stress-melted" DNA are also included in our model, allowing prediction of a global phase diagram for forces up to 1000 pN and torques between ±60 pN nm, or, in terms of linking number density, from σ=-5 to +3.

  2. Climate change underlies global demographic, genetic, and cultural transitions in pre-Columbian southern Peru.

    PubMed

    Fehren-Schmitz, Lars; Haak, Wolfgang; Mächtle, Bertil; Masch, Florian; Llamas, Bastien; Cagigao, Elsa Tomasto; Sossna, Volker; Schittek, Karsten; Isla Cuadrado, Johny; Eitel, Bernhard; Reindel, Markus

    2014-07-01

    Several archaeological studies in the Central Andes have pointed at the temporal coincidence of climatic fluctuations (both long- and short-term) and episodes of cultural transition and changes of socioeconomic structures throughout the pre-Columbian period. Although most scholars explain the connection between environmental and cultural changes by the impact of climatic alterations on the capacities of the ecosystems inhabited by pre-Columbian cultures, direct evidence for assumed demographic consequences is missing so far. In this study, we address directly the impact of climatic changes on the spatial population dynamics of the Central Andes. We use a large dataset of pre-Columbian mitochondrial DNA sequences from the northern Rio Grande de Nasca drainage (RGND) in southern Peru, dating from ∼840 BC to 1450 AD. Alternative demographic scenarios are tested using Bayesian serial coalescent simulations in an approximate Bayesian computational framework. Our results indicate migrations from the lower coastal valleys of southern Peru into the Andean highlands coincident with increasing climate variability at the end of the Nasca culture at ∼640 AD. We also find support for a back-migration from the highlands to the coast coincident with droughts in the southeastern Andean highlands and improvement of climatic conditions on the coast after the decline of the Wari and Tiwanaku empires (∼1200 AD), leading to a genetic homogenization in the RGND and probably southern Peru as a whole.

  3. Climate change underlies global demographic, genetic, and cultural transitions in pre-Columbian southern Peru

    PubMed Central

    Fehren-Schmitz, Lars; Haak, Wolfgang; Mächtle, Bertil; Masch, Florian; Llamas, Bastien; Tomasto Cagigao, Elsa; Sossna, Volker; Schittek, Karsten; Isla Cuadrado, Johny; Eitel, Bernhard; Reindel, Markus

    2014-01-01

    Several archaeological studies in the Central Andes have pointed at the temporal coincidence of climatic fluctuations (both long- and short-term) and episodes of cultural transition and changes of socioeconomic structures throughout the pre-Columbian period. Although most scholars explain the connection between environmental and cultural changes by the impact of climatic alterations on the capacities of the ecosystems inhabited by pre-Columbian cultures, direct evidence for assumed demographic consequences is missing so far. In this study, we address directly the impact of climatic changes on the spatial population dynamics of the Central Andes. We use a large dataset of pre-Columbian mitochondrial DNA sequences from the northern Rio Grande de Nasca drainage (RGND) in southern Peru, dating from ∼840 BC to 1450 AD. Alternative demographic scenarios are tested using Bayesian serial coalescent simulations in an approximate Bayesian computational framework. Our results indicate migrations from the lower coastal valleys of southern Peru into the Andean highlands coincident with increasing climate variability at the end of the Nasca culture at ∼640 AD. We also find support for a back-migration from the highlands to the coast coincident with droughts in the southeastern Andean highlands and improvement of climatic conditions on the coast after the decline of the Wari and Tiwanaku empires (∼1200 AD), leading to a genetic homogenization in the RGND and probably southern Peru as a whole. PMID:24979787

  4. NOW AND THEN: The Global Nutrition Transition: The Pandemic of Obesity in Developing Countries

    PubMed Central

    Popkin, Barry M.; Adair, Linda S.; Ng, Shu Wen

    2011-01-01

    Decades ago discussion of an impending global pandemic of obesity was thought of as heresy. Diets in the 1970’s began to shift toward increased reliance upon processed foods, increased away from home intake and greater use of edible oils and sugar-sweetened beverages. Reduced physical activity and increased sedentary time was seen also. These changes began in the early 1990-‘s in the low and middle income world but did not become clearly recognized until diabetes, hypertension and obesity began to dominate the globe. Urban and rural areas from sub-Saharan Africa and South Asia’s poorest countries to the higher income ones are shown to have experienced rapid increases in overweight and obesity status. Concurrent rapid shifts in diet and activity are documented. An array of large-scale programmatic and policy shifts are being explored in a few countries; however despite the major health challenges faced, few countries are serious in addressing prevention of the dietary challenges faced. PMID:22221213

  5. The Campanian - Maastrichtian (Late Cretaceous) climate transition linked to a global carbon cycle perturbation

    NASA Astrophysics Data System (ADS)

    Voigt, S.; Friedrich, O.; Gale, A. S.

    2009-04-01

    The Late Cretaceous was a period of long-term climate cooling succeeding the extreme warmth of the mid-Cretaceous greenhouse world. The cooling is mainly considered as a result of changes in ocean circulation due to plate movements resulting in progressive deep-water exchange between the deep oceanic basins and a parallel drop in atmospheric carbon dioxide concentrations. In Campanian - Maastrichtian times, pronounced climate cooling is documented between 71 - 69 Ma, when distinct changes in foraminiferal oxygen and carbon isotope data at a global scale indicate substantial deep-water cooling and reduced rates of organic carbon burial. The causal mechanisms of this cooling period, however, are poorly understood to date. While some authors suggest mainly oceanographic changes, others supposed an ephemeral glaciation related to a eustatic sea-level fall. Mainly, the relative timing of oceanic oxygen and carbon isotope changes to eustatic sea-level changes is not proven yet. Likewise, the influence of plate tectonic changes as the opening of gateways or the subduction of mid-ocean ridges and/or of orbital forcing is poorly understood. A principle objection beside the sparse available data is the low temporal resolution of biostratigraphic zonations. Here, we present carbon isotope stratigraphies from Campanian-Maastrichtian Boundary sites in the Boreal and Tethyan shelf seas of Europe and from Shatsky Rise in the tropical Pacific in order to improve the resolution of stratigraphic correlation. Prominent features at that time are two negative carbon isotope excursions (CIEs) in the late Campanian and earliest Maastrichtian, which are well documented in the Lägerdorf-Kronsmoor section in N-Germany and the Campanian-Maastrichtian Boundary Stratotype at Tercis in SW France. These new carbon isotope records correlate well with the carbon isotope reference curve from the English Chalk (Jarvis et al., 2002, 2006). The new carbon isotope record at Site 305 in the tropical

  6. Uneven dietary development: linking the policies and processes of globalization with the nutrition transition, obesity and diet-related chronic diseases

    PubMed Central

    Hawkes, Corinna

    2006-01-01

    In a "nutrition transition", the consumption of foods high in fats and sweeteners is increasing throughout the developing world. The transition, implicated in the rapid rise of obesity and diet-related chronic diseases worldwide, is rooted in the processes of globalization. Globalization affects the nature of agri-food systems, thereby altering the quantity, type, cost and desirability of foods available for consumption. Understanding the links between globalization and the nutrition transition is therefore necessary to help policy makers develop policies, including food policies, for addressing the global burden of chronic disease. While the subject has been much discussed, tracing the specific pathways between globalization and dietary change remains a challenge. To help address this challenge, this paper explores how one of the central mechanisms of globalization, the integration of the global marketplace, is affecting the specific diet patterns. Focusing on middle-income countries, it highlights the importance of three major processes of market integration: (I) production and trade of agricultural goods; (II) foreign direct investment in food processing and retailing; and (III) global food advertising and promotion. The paper reveals how specific policies implemented to advance the globalization agenda account in part for some recent trends in the global diet. Agricultural production and trade policies have enabled more vegetable oil consumption; policies on foreign direct investment have facilitated higher consumption of highly-processed foods, as has global food marketing. These dietary outcomes also reflect the socioeconomic and cultural context in which these policies are operating. An important finding is that the dynamic, competitive forces unleashed as a result of global market integration facilitates not only convergence in consumption habits (as is commonly assumed in the "Coca-Colonization" hypothesis), but adaptation to products targeted at different

  7. Uneven dietary development: linking the policies and processes of globalization with the nutrition transition, obesity and diet-related chronic diseases.

    PubMed

    Hawkes, Corinna

    2006-03-28

    In a "nutrition transition", the consumption of foods high in fats and sweeteners is increasing throughout the developing world. The transition, implicated in the rapid rise of obesity and diet-related chronic diseases worldwide, is rooted in the processes of globalization. Globalization affects the nature of agri-food systems, thereby altering the quantity, type, cost and desirability of foods available for consumption. Understanding the links between globalization and the nutrition transition is therefore necessary to help policy makers develop policies, including food policies, for addressing the global burden of chronic disease. While the subject has been much discussed, tracing the specific pathways between globalization and dietary change remains a challenge. To help address this challenge, this paper explores how one of the central mechanisms of globalization, the integration of the global marketplace, is affecting the specific diet patterns. Focusing on middle-income countries, it highlights the importance of three major processes of market integration: (I) production and trade of agricultural goods; (II) foreign direct investment in food processing and retailing; and (III) global food advertising and promotion. The paper reveals how specific policies implemented to advance the globalization agenda account in part for some recent trends in the global diet. Agricultural production and trade policies have enabled more vegetable oil consumption; policies on foreign direct investment have facilitated higher consumption of highly-processed foods, as has global food marketing. These dietary outcomes also reflect the socioeconomic and cultural context in which these policies are operating. An important finding is that the dynamic, competitive forces unleashed as a result of global market integration facilitates not only convergence in consumption habits (as is commonly assumed in the "Coca-Colonization" hypothesis), but adaptation to products targeted at different

  8. The Hetu'u Global Network: Measuring the Distance to the Sun Using the June 5th/6th Transit of Venus

    ERIC Educational Resources Information Center

    Faherty, Jacqueline K.; Rodriguez, David R.; Miller, Scott T.

    2012-01-01

    In the spirit of historic astronomical endeavors, we invited school groups across the globe to collaborate in a solar distance measurement using the rare June 5/6th transit of Venus. In total, we recruited 19 school groups spread over 6 continents and 10 countries to participate in our Hetu'u Global Network. Applying the methods of French…

  9. PPAR{gamma} ligands induce growth inhibition and apoptosis through p63 and p73 in human ovarian cancer cells

    SciTech Connect

    Kim, Soyeon; Lee, Jae-Jung; Heo, Dae Seog

    2011-03-18

    Research highlights: {yields} PPAR{gamma} ligands increased the rate of apoptosis and inhibition of proliferation in ovarian cancer cells. {yields} PPAR{gamma} ligands induced p63 and p73 expression, but not p53. {yields} p63 and p73 leads to an increase in p21 expression and apoptosis in ovarian cancer cells with treatment PPAR{gamma} ligands. {yields} These findings suggest that PPAR{gamma} ligands suppressed growth of ovarian cancer cells through upregulation of p63 and p73. -- Abstract: Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) agonists, including thiazolidinediones (TZDs), can induce anti-proliferation, differentiation, and apoptosis in various cancer cell types. This study investigated the mechanism of the anticancer effect of TZDs on human ovarian cancer. Six human ovarian cancer cell lines (NIH:OVCAR3, SKOV3, SNU-251, SNU-8, SNU-840, and 2774) were treated with the TZD, which induced dose-dependent inhibition of cell growth. Additionally, these cell lines exhibited various expression levels of PPAR{gamma} protein as revealed by Western blotting. Flow cytometry showed that the cell cycle was arrested at the G1 phase, as demonstrated by the appearance of a sub-G1 peak. This observation was corroborated by the finding of increased levels of Bax, p21, PARP, and cleaved caspase 3 in TGZ-treated cells. Interestingly, when we determined the effect of p53-induced growth inhibition in these three human ovarian cancer cells, we found that they either lacked p53 or contained a mutant form of p53. Furthermore, TGZ induced the expression of endogenous or exogenous p63 and p73 proteins and p63- or p73-directed short hairpin (si) RNAs inhibited the ability of TGZ to regulate expression of p21 in these cells. Thus, our results suggest that PPAR{gamma} ligands can induce growth suppression of ovarian cancer cells and mediate p63 and p73 expression, leading to enhanced growth inhibition and apoptosis. The tumor suppressive effects of PPAR{gamma} ligands

  10. Global transcriptional response of Escherichia coli O157:H7 to growth transitions in glucose minimal medium

    PubMed Central

    Bergholz, Teresa M; Wick, Lukas M; Qi, Weihong; Riordan, James T; Ouellette, Lindsey M; Whittam, Thomas S

    2007-01-01

    Background: Global patterns of gene expression of Escherichia coli K-12 during growth transitions have been deeply investigated, however, comparable studies of E. coli O157:H7 have not been explored, particularly with respect to factors regulating virulence genes and genomic islands specific to this pathogen. To examine the impact of growth phase on the dynamics of the transcriptome, O157:H7 Sakai strain was cultured in MOPS minimal media (0.1% glucose), RNA harvested at 10 time points from early exponential to full stationary phase, and relative gene expression was measured by co-hybridization on high-density DNA microarrays. Expression levels of 14 genes, including those encoding Shiga toxins and other virulence factors associated with the locus of enterocyte effacement (LEE), were confirmed by Q-PCR. Results: Analysis of variance (R/MAANOVA, Fs test) identified 442 (36%) of 1239 O157-specific ORFs and 2110 (59%) of 3647 backbone ORFs that changed in expression significantly over time. QT cluster analysis placed 2468 of the 2552 significant ORFs into 12 groups; each group representing a distinct expression pattern. ORFs from the largest cluster (n = 1078) decreased in expression from late exponential to early stationary phase: most of these ORFs are involved in functions associated with steady state growth. Also represented in this cluster are ORFs of the TAI island, encoding tellurite resistance and urease activity, which decreased ~4-fold. Most ORFs of the LEE pathogenicity island also decreased ~2-fold by early stationary phase. The ORFs encoding proteins secreted via the LEE encoded type III secretion system, such as tccP and espJ, also decreased in expression from exponential to stationary phase. Three of the clusters (n = 154) comprised genes that are transiently upregulated at the transition into stationary phase and included genes involved in nutrient scavenging. Upregulated genes with an increase in mRNA levels from late exponential to early stationary

  11. Ligand-induced internalization, recycling, and resensitization of adrenomedullin receptors depend not on CLR or RAMP alone but on the receptor complex as a whole.

    PubMed

    Nag, Kakon; Sultana, Naznin; Kato, Akira; Dranik, Anna; Nakamura, Nobuhiro; Kutsuzawa, Koichi; Hirose, Shigehisa; Akaike, Toshihiro

    2015-02-01

    Adrenomedullins (AM) is a multifaceted distinct subfamily of peptides that belongs to the calcitonin gene-related peptide (CGRP) superfamily. These peptides exert their functional activities via associations of calcitonin receptor-like receptors (CLRs) and receptor activity-modifying proteins (RAMPs) RAMP2 and RAMP3. Recent studies established that RAMPs and CLRs can modify biochemical properties such as trafficking and glycosylation of each other. However there is very little or no understanding regarding how RAMP or CLR influence ligand-induced events of AM-receptor complex. In this study, using pufferfish homologs of CLR (mfCLR1-3) and RAMP (mfRAMP2 and mfRAMP3), we revealed that all combinations of CLR and RAMP quickly underwent ligand-induced internalization; however, their recycling rates were different as follows: mfCLR1-mfRAMP3>mfCLR2-mfRAMP3>mfCLR3-mfRAMP3. Functional receptor assay confirmed that the recycled receptors were resensitized on the plasma membrane. In contrast, a negligible amount of mfCLR1-mfRAMP2 was recycled and reconstituted. Immunocytochemistry results indicated that the lower recovery rate of mfCLR3-mfRAMP3 and mfCLR1-mfRAMP2 was correlated with higher proportion of lysosomal localization of these receptor complexes compared to the other combinations. Collectively our results indicate, for the first time, that the ligand-induced internalization, recycling, and reconstitution properties of RAMP-CLR receptor complexes depend on the receptor-complex as a whole, and not on individual CLR or RAMP alone.

  12. TGF-β induces global changes in DNA methylation during the epithelial-to-mesenchymal transition in ovarian cancer cells

    PubMed Central

    Cardenas, Horacio; Vieth, Edyta; Lee, Jiyoon; Segar, Mathew; Liu, Yunlong; Nephew, Kenneth P; Matei, Daniela

    2014-01-01

    A key step in the process of metastasis is the epithelial-to-mesenchymal transition (EMT). We hypothesized that epigenetic mechanisms play a key role in EMT and to test this hypothesis we analyzed global and gene-specific changes in DNA methylation during TGF-β-induced EMT in ovarian cancer cells. Epigenetic profiling using the Infinium HumanMethylation450 BeadChip (HM450) revealed extensive (P < 0.01) methylation changes after TGF-β stimulation (468 and 390 CpG sites altered at 48 and 120 h post cytokine treatment, respectively). The majority of gene-specific TGF-β-induced methylation changes occurred in CpG islands located in or near promoters (193 and 494 genes hypermethylated at 48 and 120 h after TGF-β stimulation, respectively). Furthermore, methylation changes were sustained for the duration of TGF-β treatment and reversible after the cytokine removal. Pathway analysis of the hypermethylated loci identified functional networks strongly associated with EMT and cancer progression, including cellular movement, cell cycle, organ morphology, cellular development, and cell death and survival. Altered methylation and corresponding expression of specific genes during TGF-β-induced EMT included CDH1 (E-cadherin) and COL1A1 (collagen 1A1). Furthermore, TGF-β induced both expression and activity of DNA methyltransferases (DNMT) -1, -3A, and -3B, and treatment with the DNMT inhibitor SGI-110 prevented TGF-β-induced EMT. These results demonstrate that dynamic changes in the DNA methylome are implicated in TGF-β-induced EMT and metastasis. We suggest that targeting DNMTs may inhibit this process by reversing the EMT genes silenced by DNA methylation in cancer. PMID:25470663

  13. TGF-β induces global changes in DNA methylation during the epithelial-to-mesenchymal transition in ovarian cancer cells.

    PubMed

    Cardenas, Horacio; Vieth, Edyta; Lee, Jiyoon; Segar, Mathew; Liu, Yunlong; Nephew, Kenneth P; Matei, Daniela

    2014-11-01

    A key step in the process of metastasis is the epithelial-to-mesenchymal transition (EMT). We hypothesized that epigenetic mechanisms play a key role in EMT and to test this hypothesis we analyzed global and gene-specific changes in DNA methylation during TGF-β-induced EMT in ovarian cancer cells. Epigenetic profiling using the Infinium HumanMethylation450 BeadChip (HM450) revealed extensive (P < 0.01) methylation changes after TGF-β stimulation (468 and 390 CpG sites altered at 48 and 120 h post cytokine treatment, respectively). The majority of gene-specific TGF-β-induced methylation changes occurred in CpG islands located in or near promoters (193 and 494 genes hypermethylated at 48 and 120 h after TGF-β stimulation, respectively). Furthermore, methylation changes were sustained for the duration of TGF-β treatment and reversible after the cytokine removal. Pathway analysis of the hypermethylated loci identified functional networks strongly associated with EMT and cancer progression, including cellular movement, cell cycle, organ morphology, cellular development, and cell death and survival. Altered methylation and corresponding expression of specific genes during TGF-β-induced EMT included CDH1 (E-cadherin) and COL1A1 (collagen 1A1). Furthermore, TGF-β induced both expression and activity of DNA methyltransferases (DNMT) -1, -3A, and -3B, and treatment with the DNMT inhibitor SGI-110 prevented TGF-β-induced EMT. These results demonstrate that dynamic changes in the DNA methylome are implicated in TGF-β-induced EMT and metastasis. We suggest that targeting DNMTs may inhibit this process by reversing the EMT genes silenced by DNA methylation in cancer.

  14. Staggering Changes in Mediterranean Sea Surface Temperatures Coincide with Global Climate and Evolution Transitions during the Late Miocene - Pliocene

    NASA Astrophysics Data System (ADS)

    Tzanova, A.; Herbert, T.; Peterson, L.

    2012-12-01

    crisis and SST proxy data from the Rosello section shows a continuation of the late Miocene cooling trend into the earliest Pliocene as well as increase in the amplitude of variability. The onset of cooling in the Mediterranean coincides with the widespread C3/C4 plant transition suggesting a strong coherence between the terrestrial and marine realm during this time period. We hypothesize that in the Late Miocene a widespread cooling possibly driven by pCO2 changes coupled with orbital forcing set the stage for environmental and evolutionary changes on land. The changing landscape illustrated by expansion of grasslands and the emergence of the Sahara desert could have initiated an albedo-cooling feedback and set the stage for Northern Hemisphere Glaciation in the Pliocene. The Mediterranean records reconstruct climate changes currently observed in other paleoreconstructions but not captured by the global δ18O record. Our first, continuous SST record from the Mediterranean over this time period allows for the evaluation of marine-terrestrial connections on both long term and orbital time scale, continental climate change, plant, grazer and hominin evolution, thresholds for climate change and changes in climate forcing.

  15. CXCR1/2 ligands induce p38 MAPK-dependent translocation and release of opioid peptides from primary granules in vitro and in vivo.

    PubMed

    Rittner, Heike L; Labuz, Dominika; Richter, Jan F; Brack, Alexander; Schäfer, Michael; Stein, Christoph; Mousa, Shaaban A

    2007-11-01

    Polymorphonuclear leukocytes (PMN) can release opioid peptides which bind to opioid receptors on sensory neurons and inhibit inflammatory pain. This release can be triggered by chemokine receptor 1/2 (CXCR1/2) ligands. Our aim was to identify the granule subpopulation containing opioid peptides and to assess whether MAPK mediate the CXCR1/2 ligand-induced release of these peptides. Using double immunofluorescence confocal microscopy, we showed that beta-endorphin (END) and Met-enkephalin (ENK) were colocalized with the primary (azurophil) granule markers CD63 and myeloperoxidase (MPO) within PMN. END and ENK release triggered by a CXCR1/2 ligand in vitro was dependent on the presence of cytochalasin B (CyB) and on p38 MAPK, but not on p42/44 MAPK. In addition, translocation of END and ENK containing primary granules to submembranous regions of the cell was abolished by the p38 MAPK inhibitor SB203580. In vivo CXCL2/3 reduced pain in rats with complete Freund's adjuvant (CFA)-induced hindpaw inflammation. This effect was attenuated by intraplantar (i.pl.) antibodies against END and ENK and by i.pl. p38 MAPK inhibitor treatment. Taken together, these findings indicate that END and ENK are contained in primary granules of PMN, and that CXCR1/2 ligands induce p38-dependent translocation and release of these opioid peptides to inhibit inflammatory pain.

  16. Dual inhibition of AKT/FLT3-ITD by A674563 overcomes FLT3 ligand-induced drug resistance in FLT3-ITD positive AML

    PubMed Central

    Wang, Wenchao; Yu, Kailin; Liu, Xiaochuan; Zou, Fengming; Zhao, Zheng; Wu, Jiaxin; Liu, Juan; Liu, Feiyang; Wang, Li; Stone, Richard M.; Galinksy, Ilene A.; Griffin, James D.; Zhang, Shanchun; Weisberg, Ellen L.; Liu, Jing; Liu, Qingsong

    2016-01-01

    The FLT3-ITD mutation is one of the most prevalent oncogenic mutations in AML. Several FLT3 kinase inhibitors have shown impressive activity in clinical evaluation, however clinical responses are usually transient and clinical effects are rapidly lost due to drug resistance. One of the resistance mechanisms in the AML refractory patients involves FLT3-ligand induced reactivation of AKT and/or ERK signaling via FLT3 wt kinase. Via a screen of numerous AKT kinase inhibitors, we identified the well-established orally available AKT inhibitor, A674563, as a dual suppressor of AKT and FLT3-ITD. A674563 suppressed FLT3-ITD positive AML both in vitro and in vivo. More importantly, compared to other FLT3 inhibitors, A674563 is able to overcome FLT3 ligand-induced drug resistance through simultaneous inhibition of FLT3-ITD- and AKT-mediated signaling. Our findings suggest that A674563 might be a potential drug candidate for overcoming FLT3 ligand-mediated drug resistance in FLT3-ITD positive AML. PMID:27074558

  17. Formation of retinoid X receptor homodimers leads to repression of T3 response: hormonal cross talk by ligand-induced squelching.

    PubMed Central

    Lehmann, J M; Zhang, X K; Graupner, G; Lee, M O; Hermann, T; Hoffmann, B; Pfahl, M

    1993-01-01

    Thyroid hormone receptors (TRs) form heterodimers with retinoid X receptors (RXRs). Heterodimerization is required for efficient TR DNA binding to most response elements and transcriptional activation by thyroid hormone. RXRs also function as auxiliary proteins for several other receptors. In addition, RXR alpha can be induced by specific ligands to form homodimers. Here we report that RXR-specific retinoids that induce RXR homodimers are effective repressors of the T3 response. We provide evidence that this repression by RXR-specific ligands occurs by sequestering of RXR from TR-RXR heterodimers into RXR homodimers. This ligand-induced squelching may represent an important mechanism by which RXR-specific retinoids and 9-cis retinoic acid mediate hormonal cross talk among a subfamily of nuclear receptors activated by structurally unrelated ligands. Images PMID:8246986

  18. Combining ligand-induced quantum-confined stark effect with type II heterojunction bilayer structure in CdTe and CdSe nanocrystal-based solar cells.

    PubMed

    Yaacobi-Gross, Nir; Garphunkin, Natalia; Solomeshch, Olga; Vaneski, Aleksandar; Susha, Andrei S; Rogach, Andrey L; Tessler, Nir

    2012-04-24

    We show that it is possible to combine several charge generation strategies in a single device structure, the performance of which benefits from all methods used. Exploiting the inherent type II heterojunction between layered structures of CdSe and CdTe colloidal quantum dots, we systematically study different ways of combining such nanocrystals of different size and surface chemistry and with different linking agents in a bilayer solar cell configuration. We demonstrate the beneficial use of two distinctly different sizes of NCs not only to improve the solar spectrum matching but also to reduce exciton binding energy, allowing their efficient dissociation at the interface. We further make use of the ligand-induced quantum-confined Stark effect in order to enhance charge generation and, hence, overall efficiency of nanocrystal-based solar cells.

  19. Ligand-induced interaction between. alpha. - and. beta. -type platelet-derived growth factor (PDGF) receptors: Role of receptor heterodimers in kinase activation

    SciTech Connect

    Kanakaraj, P.; Raj, S.; Bishayee, S. ); Khan, S.A. )

    1991-02-19

    Two types of PDGF receptors have been cloned and sequenced. Both receptors are transmembrane glycoproteins with a ligand-stimulatable tyrosine kinase site. The authors have shown earlier that ligand-induced activation of the {beta}-type PDGF receptor is due to the conversion of the monomeric form of the receptor to the dimeric form. In the present studies, they have established the ligand-binding specificity of two receptor types and extended it further to investigate the ligand-induced association state of the {alpha}-receptor and the role of {alpha}-receptor in the activation of {beta}-receptor. These studies were conducted with cells that express one or the other type of PDGF receptor as well as with cells that express both types of receptors. Moreover, ligand-binding characteristics of the receptor were confirmed by immunoprecipitation of the receptor-{sup 125}I-PDGF covalent complex with type-specific anti-PDGF receptor antibodies. These studies revealed that all three isoforms of PDGF bind to {alpha}-receptor, and such binding leads to dimerization as well as activation of the receptor. In contrast, {beta}-receptor can be activated only by PDGF BB and not by PDGF AB or PDGF AA. However, by using antipeptide antibodies that are specific for {alpha}- or {beta}-type PDGF receptor, they demonstrated that in the presence of {alpha}-receptor, {beta}-receptor kinase can be activated by PDGF AB. They present here direct evidence that strongly suggests that such PDGF AB induced activation of {beta}-receptor is due to the formation of a noncovalently linked {alpha}-{beta} receptor heterodimer.

  20. Expression of Vascular Endothelial Growth Factor A During Ligand-Induced Down-Regulation of Luteinizing Hormone Receptor in the Ovary☆

    PubMed Central

    Harada, M.; Peegel, H.; Menon, K. M. J.

    2010-01-01

    Vascular endothelial growth factor A (VEGF-A) is one of the most important regulators of ovarian angiogenesis. In this study, we examined the temporal relationship between VEGF-A and luteinizing hormone receptor (LHR) mRNA expression during ligand-induced down-regulation of LHR. Immature female rats were treated with pregnant mare’s serum gonadotropin followed by 25 IU hCG 56h later (day 0). On day 5, treatment with hCG (50 IU) to down-regulate LHR showed a temporal decrease in VEGF-A mRNA and protein levels in parallel with decreasing LHR mRNA. This effect was specific since the expression of CYP11A1 mRNA showed no decline. Examination of VEGF-A mRNA expression, using in situ hybridization histochemistry with 35S-labeled antisense VEGF-A mRNA probe, showed intense signal in the corpora lutea on day 5. Treatment with 50 IU hCG to down-regulate LHR mRNA showed a decline in the intensity of VEGF-A mRNA in the corpora lutea. VEGF-A mRNA expression returned to control level 53 hours later when the expression of LHR mRNA also recovered. These results show that the transient down-regulation of VEGF-A mRNA and protein closely parallels the ligand-induced down-regulation of LHR mRNA. The present study establishes a close association between VEGF-A and LHR mRNA expression, suggesting the possibility that VEGF-A-induced vascularization of the ovary is dictated by the expression of LHR and this might play a regulatory role in ovarian physiology. PMID:20619315

  1. CADASIL-associated Notch3 mutations have differential effects both on ligand binding and ligand-induced Notch3 receptor signaling through RBP-Jk.

    PubMed

    Peters, Nils; Opherk, Christian; Zacherle, Simone; Capell, Anja; Gempel, Petra; Dichgans, Martin

    2004-10-01

    Mutations in the NOTCH3 gene are the cause of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a hereditary angiopathy leading to strokes and dementia. Pathogenic mutations remove or insert cysteine residues within epidermal growth factor (EGF) repeats in the extracellular domain of the Notch3 receptor (N3ECD). Vascular smooth muscle cells (VSMC) are the predominant site of Notch3 expression in adults. In CADASIL patients, VSMC degenerate and N3ECD is deposited within the vasculature. However, the mechanisms underlying VSMC degeneration and N3ECD accumulation are still unknown. In this study, we investigated the consequences of three pathogenic Notch3 mutations on the biological activity of the receptor by analyzing ligand (Delta-/Jagged-)-induced signaling via RBP-Jk. Two mutations (R133C and C183R) that are located outside the putative ligand binding domain (LBD) of the receptor were found to result in normal Jagged1-induced signaling in A7r5 VSMC, whereas the third mutation (C455R located within the putative LBD) showed strongly reduced signaling activity. Ligand binding assays with soluble Delta1 and Jagged1 revealed that C455R interferes with ligand binding through disruption of the LBD which, as we show here, is located in EGF repeats 10/11 of Notch3. All mutant receptors including Notch3C455R were targeted to the cell surface but showed an elevated ratio between the unprocessed full-length 280-kDa receptor and S1-cleaved receptor fragments. Taken together, these data indicate that CADASIL-associated Notch3 mutations differ with respect to their consequences both on ligand binding and ligand-induced signaling through RBP-Jk, whereas they have similar effects on receptor maturation. Moreover, the data suggest that ligand-induced receptor shedding may not be required for N3ECD deposition in CADASIL.

  2. Curriculum on the European Policy Agenda: Global Transitions and Learning Outcomes from Transnational and National Points of View

    ERIC Educational Resources Information Center

    Sivesind, Kirsten; Wahlström, Ninni

    2016-01-01

    This special issue examines curricula and their histories as they have evolved throughout the 21st century as part of transnational and national education policies. With a specific focus on the policy transitions that are taking place in Europe, the articles demonstrate how curriculum making processes move in different directions, following their…

  3. Response of the Pacific inter-tropical convergence zone to global cooling and initiation of Antarctic glaciation across the Eocene Oligocene Transition

    NASA Astrophysics Data System (ADS)

    Hyeong, Kiseong; Kuroda, Junichiro; Seo, Inah; Wilson, Paul A.

    2016-08-01

    Approximately 34 million years ago across the Eocene–Oligocene transition (EOT), Earth’s climate tipped from a largely unglaciated state into one that sustained large ice sheets on Antarctica. Antarctic glaciation is attributed to a threshold response to slow decline in atmospheric CO2 but our understanding of the feedback processes triggered and of climate change on the other contents is limited. Here we present new geochemical records of terrigenous dust accumulating on the sea floor across the EOT from a site in the central equatorial Pacific. We report a change in dust chemistry from an Asian affinity to a Central-South American provenance that occurs geologically synchronously with the initiation of stepwise global cooling, glaciation of Antarctica and aridification on the northern continents. We infer that the inter-tropical convergence zone of intense precipitation extended to our site during late Eocene, at least four degrees latitude further south than today, but that it migrated northwards in step with global cooling and initiation of Antarctic glaciation. Our findings point to an atmospheric teleconnection between extratropical cooling and rainfall climate in the tropics and the mid-latitude belt of the westerlies operating across the most pivotal transition in climate state of the Cenozoic Era.

  4. Response of the Pacific inter-tropical convergence zone to global cooling and initiation of Antarctic glaciation across the Eocene Oligocene Transition.

    PubMed

    Hyeong, Kiseong; Kuroda, Junichiro; Seo, Inah; Wilson, Paul A

    2016-08-10

    Approximately 34 million years ago across the Eocene-Oligocene transition (EOT), Earth's climate tipped from a largely unglaciated state into one that sustained large ice sheets on Antarctica. Antarctic glaciation is attributed to a threshold response to slow decline in atmospheric CO2 but our understanding of the feedback processes triggered and of climate change on the other contents is limited. Here we present new geochemical records of terrigenous dust accumulating on the sea floor across the EOT from a site in the central equatorial Pacific. We report a change in dust chemistry from an Asian affinity to a Central-South American provenance that occurs geologically synchronously with the initiation of stepwise global cooling, glaciation of Antarctica and aridification on the northern continents. We infer that the inter-tropical convergence zone of intense precipitation extended to our site during late Eocene, at least four degrees latitude further south than today, but that it migrated northwards in step with global cooling and initiation of Antarctic glaciation. Our findings point to an atmospheric teleconnection between extratropical cooling and rainfall climate in the tropics and the mid-latitude belt of the westerlies operating across the most pivotal transition in climate state of the Cenozoic Era.

  5. Response of the Pacific inter-tropical convergence zone to global cooling and initiation of Antarctic glaciation across the Eocene Oligocene Transition

    PubMed Central

    Hyeong, Kiseong; Kuroda, Junichiro; Seo, Inah; Wilson, Paul A.

    2016-01-01

    Approximately 34 million years ago across the Eocene–Oligocene transition (EOT), Earth’s climate tipped from a largely unglaciated state into one that sustained large ice sheets on Antarctica. Antarctic glaciation is attributed to a threshold response to slow decline in atmospheric CO2 but our understanding of the feedback processes triggered and of climate change on the other contents is limited. Here we present new geochemical records of terrigenous dust accumulating on the sea floor across the EOT from a site in the central equatorial Pacific. We report a change in dust chemistry from an Asian affinity to a Central-South American provenance that occurs geologically synchronously with the initiation of stepwise global cooling, glaciation of Antarctica and aridification on the northern continents. We infer that the inter-tropical convergence zone of intense precipitation extended to our site during late Eocene, at least four degrees latitude further south than today, but that it migrated northwards in step with global cooling and initiation of Antarctic glaciation. Our findings point to an atmospheric teleconnection between extratropical cooling and rainfall climate in the tropics and the mid-latitude belt of the westerlies operating across the most pivotal transition in climate state of the Cenozoic Era. PMID:27507793

  6. 3D Global PIC simulation of Alfvenic transition layers at the cusp outer boundary during IMF rotations from north to south

    NASA Astrophysics Data System (ADS)

    Cai, D. S.; Lembege, B.; Esmaeili, A.; Nishikawa, K.

    2013-12-01

    Statistical experimental observations of the cusp boundaries from CLUSTER mission made by Lavraud et al. (2005) have clearly evidenced the presence of a transition layer inside the magnetosheath near the outer boundary of the cusp. This layer characterized by Log(MA)~ 1 allows a transition from super-Alfvenic to sub-Alfvenic bulk flow from the exterior to the interior side of the outer cusp and has been mainly observed experimentally under northward interplanetary magnetic field (IMF). The role of this layer is important in order to understand the flow variations (and later the entry and precipitation of particles) when penetrating the outer boundary of the cusp. In order to analyze this layer, a large 3D PIC simulation of the global solar wind-terrestrial magnetosphere interaction have been performed, and the attention has been focused on the cusp region and its nearby surrounding during IMF rotation from north to south. Present results retrieve quite well the presence of this layer within the meridian plane for exactly northward IMF, but its location differs in the sense that it is located slightly below the X reconnection region associated to the nearby magnetopause (above the outer boundary of the cusp). In order to clarify this question, an extensive study has been performed as follows: (i) a 3D mapping of this transition layer in order to analyze more precisely the thickness, the location and the spatial extension of this layer on the magnetosphere flanks for a fixed Northward IMF configuration; (ii) a parametric study in order to analyze the impact of the IMF rotation from north to south on the persistence and the main features of this transition layer. The locations of this transition layer slightly radially expand and shrink during the IMF rotation and the thickness of the layer increases during the rotation. We show how these transition layers render the flow from super to sub Alfvenic and allow the particles enter into the magnetic cusp region. Alfven

  7. Global two-fluid turbulence simulations of L-H transitions and edge localized mode dynamics in the COMPASS-D tokamak

    NASA Astrophysics Data System (ADS)

    Thyagaraja, A.; Valovič, M.; Knight, P. J.

    2010-04-01

    It is shown that the transition from L-mode to H-mode regimes in tokamaks can be reproduced using a two-fluid, fully electromagnetic, plasma model when a suitable particle sink is added at the edge. Such a model is implemented in the CUTIE code [A. Thyagaraja et al., Eur. J. Mech. B/Fluids 23, 475 (2004)] and is illustrated on plasma parameters that mimic those in the COMPASS-D tokamak with electron cyclotron resonance heating [Fielding et al., Plasma Phys. Contr. Fusion 42, A191 (2000)]. In particular, it is shown that holding the heating power, current, and magnetic field constant and increasing the fuelling rate to raise the plasma density leads spontaneously to the formation of an edge transport barrier (ETB) which occurs going from low to higher density experimentally. In the following quiescent period in which the stored energy of the plasma rises linearly with time, a dynamical transition occurs in the simulation with the appearance of features resembling strong edge localized modes. The simulation qualitatively reproduces many features observed in the experiment. Its relative robustness suggests that some, at least of the observed characteristics of ETBs and L-H transitions, can be captured in the global electromagnetic turbulence model.

  8. Ligand-induced structural changes in the Escherichia coli ferric citrate transporter reveal modes for regulating protein-protein interactions.

    PubMed

    Mokdad, Audrey; Herrick, Dawn Z; Kahn, Ali K; Andrews, Emily; Kim, Miyeon; Cafiso, David S

    2012-11-09

    Outer-membrane TonB-dependent transporters, such as the Escherichia coli ferric citrate transporter FecA, interact with the inner-membrane protein TonB through an energy-coupling segment termed the Ton box. In FecA, which regulates its own transcription, the Ton box is preceded by an N-terminal extension that interacts with the inner-membrane protein FecR. Here, site-directed spin labeling was used to examine the structural basis for transcriptional signaling and Ton box regulation in FecA. EPR spectroscopy indicates that regions of the N-terminal domain are in conformational exchange, consistent with its role as a protein binding element; however, the local fold and dynamics of the domain are not altered by substrate or TonB. Distance restraints derived from pulse EPR were used to generate models for the position of the extension in the apo, substrate-, and TonB-bound states. In the apo state, this domain is positioned at the periplasmic surface of FecA, where it interacts with the Ton box and blocks access of the Ton box to the periplasm. Substrate addition rotates the transcriptional domain and exposes the Ton box, leading to a disorder transition in the Ton box that may facilitate interactions with TonB. When a soluble fragment of TonB is bound to FecA, the transcriptional domain is displaced to one edge of the barrel, consistent with a proposed β-strand exchange mechanism. However, neither substrate nor TonB displaces the N-terminus further into the periplasm. This result suggests that the intact TonB system mediates both signaling and transport by unfolding portions of the transporter.

  9. Recent advances in the molecular mechanisms determining tissue sensitivity to glucocorticoids: novel mutations, circadian rhythm and ligand-induced repression of the human glucocorticoid receptor

    PubMed Central

    2014-01-01

    Glucocorticoids are pleiotropic hormones, which are involved in almost every cellular, molecular and physiologic network of the organism, and regulate a broad spectrum of physiologic functions essential for life. The cellular response to glucocorticoids displays profound variability both in magnitude and in specificity of action. Tissue sensitivity to glucocorticoids differs among individuals, within tissues of the same individual and within the same cell. The actions of glucocorticoids are mediated by the glucocorticoid receptor, a ubiquitously expressed intracellular, ligand-dependent transcription factor. Multiple mechanisms, such as pre-receptor ligand metabolism, receptor isoform expression, and receptor-, tissue-, and cell type-specific factors, exist to generate diversity as well as specificity in the response to glucocorticoids. Alterations in the molecular mechanisms of glucocorticoid receptor action impair glucocorticoid signal transduction and alter tissue sensitivity to glucocorticoids. This review summarizes the recent advances in our understanding of the molecular mechanisms determining tissue sensitivity to glucocorticoids with particular emphasis on novel mutations and new information on the circadian rhythm and ligand-induced repression of the glucocorticoid receptor. PMID:25155432

  10. The role of global in-use material stocks in the course of the socio-metabolic transition, from 1900 -2009

    NASA Astrophysics Data System (ADS)

    Wiedenhofer, Dominik; Lauk, Christian; Fishman, Tomer; Tanikawa, Hiroki; Eisenmenger, Nina; Krausmann, Fridolin

    2014-05-01

    During the global socio-metabolic transition into the fossil fuelled age in the 20th century, annual material use increased nearly 10-fold (Krausmann et al. 2009). A substantial part of these materials were used to expand societal stocks such as infrastructure, buildings, factories or machinery. Long service-lifetimes lead to an ongoing accumulation of in-use stocks and determine the availability of materials for reuse and recycling. Systematic knowledge about material stock dynamics is crucial for understanding possible future resource use trends, the potential for increased recycling and thereby inform the development of strategies towards more sustainable resource use. In this presentation we explore the relationship between material use and stock accumulation, estimating global material stocks in infrastructures, buildings and durable goods from 1900 - 2009 based on a dynamic material stocks and flows model. We apply a top-down modelling approach, tracking annual cohorts of inflows of stock-building materials throughout the time period. We utilize a global material flow database and auxiliary data sources covering the time period 1850 - 2009 (Krausmann et al., 2009; Schaffartzik et al. 2013) to distinguish inputs of 11 major stock building materials: concrete, asphalt, bricks/stones/tiles, sand/gravel/crushed rocks, copper, steel, aluminum,other metals, solid-wood products, paper and plastics. Two types of functions are then used to model the lifetimes of the materials in use: A uniform distribution is applied for materials with short lifetimes, while a normal distribution is applied for materials with longer lifetimes. Furthermore, end-of-life waste is subject to recycling, thereby turning into additional input flows of non-virgin materials. Due to the inherent uncertainty in such an exercise, we perform Monte-Carlo simulations, applying uncertainty ranges for all model parameters and the material inflow data introduced above. This allows us to a) identify

  11. Global change across the Oligocene-Miocene transition: High-resolution stable isotope records from IODP Site U1334 (equatorial Pacific Ocean)

    NASA Astrophysics Data System (ADS)

    Beddow, Helen M.; Liebrand, Diederik; Sluijs, Appy; Wade, Bridget S.; Lourens, Lucas J.

    2016-01-01

    The Oligocene-Miocene transition (OMT) (~23 Ma) is interpreted as a transient global cooling event, associated with a large-scale Antarctic ice sheet expansion. Here we present a 2.23 Myr long high-resolution (~3 kyr) benthic foraminiferal oxygen and carbon isotope (δ18O and δ13C) record from Integrated Ocean Drilling Program Site U1334 (eastern equatorial Pacific Ocean), covering the interval from 21.91 to 24.14 Ma. To date, five other high-resolution benthic foraminiferal stable isotope stratigraphies across this time interval have been published, showing a ~1‰ increase in benthic foraminiferal δ18O across the OMT. However, these records are still few and spatially limited and no clear understanding exists of the global versus local imprints. We show that trends and the amplitudes of change are similar at Site U1334 as in other high-resolution stable isotope records, suggesting that these represent global deep water signals. We create a benthic foraminiferal stable isotope stack across the OMT by combining Site U1334 with records from ODP Sites 926, 929, 1090, 1264, and 1218 to best approximate the global signal. We find that isotopic gradients between sites indicate interbasinal and intrabasinal variabilities in deep water masses and, in particular, note an offset between the equatorial Atlantic and the equatorial Pacific, suggesting that a distinct temperature gradient was present during the OMT between these deep water masses at low latitudes. A convergence in the δ18O values between infaunal and epifaunal species occurs between 22.8 and 23.2 Ma, associated with the maximum δ18O excursion at the OMT, suggesting climatic changes associated with the OMT had an effect on interspecies offsets of benthic foraminifera. Our data indicate a maximum glacioeustatic sea level change of ~50 m across the OMT.

  12. The Global Cardiovascular Risk Transition: Associations of Four Metabolic Risk Factors with Macroeconomic Variables in 1980 and 2008

    PubMed Central

    Danaei, Goodarz; Singh, Gitanjali M; Paciorek, Christopher J; Lin, John K; Cowan, Melanie J; Finucane, Mariel M; Farzadfar, Farshad; Stevens, Gretchen A; Riley, Leanne M; Lu, Yuan; Rao, Mayuree; Ezzati, Majid

    2014-01-01

    Background It is commonly assumed that globally CVD risk factors are associated with affluence and Westernization. We investigated the associations of body mass index (BMI), fasting plasma glucose (FPG), systolic blood pressure (SBP), and serum total cholesterol (TC) with national income, Western diet, and (for BMI) urbanization in 1980 and 2008. Methods and Results Country-level risk factor estimates for 199 countries between 1980 and 2008 were from a previous systematic analysis of population-based data. We analyzed the associations between risk factors and natural logarithm of per-capita GDP [Ln(GDP)], a measure of Western diet, and (for BMI) percent population living in urban areas. In 1980, there was a positive association between national income and population mean BMI, SBP, and TC. By 2008, the slope of the association between Ln(GDP) and SBP became negative for women and zero for men. TC was associated with national income and Western diet throughout the period. In 1980, BMI rose with per-capita GDP and then flattened at about Int$7000; by 2008, the relationship resembled an inverted-U for women, peaking at middle income levels. BMI had a positive relationship with percent urban population in both 1980 and 2008. FPG had weaker associations with these country macro characteristics, but was positively associated with BMI. Conclusions The changing associations of metabolic risk factors with macroeconomic variables indicate that there will be a global pandemic of hyperglycemia and diabetes, together with high blood pressure in low income countries, unless effective lifestyle, and pharmacological interventions are implemented. PMID:23481623

  13. Global analyses of brachiopod faunas through the Ordovician and Silurian transition: Reducing the role of the Lazarus effect

    USGS Publications Warehouse

    Rong, J.-Y.; Boucot, A.J.; Harper, D.A.T.; Zhan, R.-B.; Neuman, R.B.

    2006-01-01

    Global analyses of 88 families and 284 genera of brachiopods from middle Ashgill, Late Ordovician, to early-middle Rhuddanian, Early Silurian, indicate that 18.6% and 12.5% of families and 51.0% and 41.3% of genera were eliminated in the first and second phases of the end-Ordovician mass extinction, respectively, with the total loss of 28.4% of families and 69.0% of genera in the crisis. New investigation demonstrates that brachiopods, at both generic and familial levels, suffered greater during the first phase than during the second phase. Four groups (victims, relicts, survivors, and new arrivals) are distinguished by their stratigraphical ranges. Generic survivors, occurring in the Kosov Province during the Hirnantian, can be split into three types with respect to their changing abundance: increasing, declining, and Lazarus taxa. Among the 88 genera that survived, numerous declining genera occurred in the Hirnantian: 16 Lazarus families and 18 Lazarus genera are provisionally known and may be regarded as end members of the declining type. Comparison of the abundance, population size, and distribution patterns of declining and Lazarus taxa shows important similarities between these two types which contribute to a better understanding of the nature of Lazarus taxa. In addition to these biological attributes, taphonomic failure and generally poor preservation, together with collecting bias and inadequate systematic data, are clearly involved. More collections will undoubtedly globally reduce the number of Lazarus taxa. A single, common refugium for end-Ordovician brachiopods probably did not exist; rather, these taxa used paleogeographically scattered locations in a range of environments for survival. ?? 2006 NRC Canada.

  14. Global gene expression shift during the transition from early neural development to late neuronal differentiation in Drosophila melanogaster.

    PubMed

    Cantera, Rafael; Ferreiro, María José; Aransay, Ana María; Barrio, Rosa

    2014-01-01

    Regulation of transcription is one of the mechanisms involved in animal development, directing changes in patterning and cell fate specification. Large temporal data series, based on microarrays across the life cycle of the fly Drosophila melanogaster, revealed the existence of groups of genes which expression increases or decreases temporally correlated during the life cycle. These groups of genes are enriched in different biological functions. Here, instead of searching for temporal coincidence in gene expression using the entire genome expression data, we searched for temporal coincidence in gene expression only within predefined catalogues of functionally related genes and investigated whether a catalogue's expression profile can be used to generate larger catalogues, enriched in genes necessary for the same function. We analyzed the expression profiles from genes already associated with early neurodevelopment and late neurodifferentiation, at embryonic stages 16 and 17 of Drosophila life cycle. We hypothesized that during this interval we would find global downregulation of genes important for early neuronal development together with global upregulation of genes necessary for the final differentiation of neurons. Our results were consistent with this hypothesis. We then investigated if the expression profile of gene catalogues representing particular processes of neural development matched the temporal sequence along which these processes occur. The profiles of genes involved in patterning, neurogenesis, axogenesis or synaptic transmission matched the prediction, with largest transcript values at the time when the corresponding biological process takes place in the embryo. Furthermore, we obtained catalogues enriched in genes involved in temporally matching functions by performing a genome-wide systematic search for genes with their highest expression levels at the corresponding embryonic intervals. These findings imply the use of gene expression data in

  15. Transition in the waiting-time distribution of price-change events in a global socioeconomic system

    NASA Astrophysics Data System (ADS)

    Zhao, Guannan; McDonald, Mark; Fenn, Dan; Williams, Stacy; Johnson, Nicholas; Johnson, Neil F.

    2013-12-01

    The goal of developing a firmer theoretical understanding of inhomogeneous temporal processes-in particular, the waiting times in some collective dynamical system-is attracting significant interest among physicists. Quantifying the deviations between the waiting-time distribution and the distribution generated by a random process may help unravel the feedback mechanisms that drive the underlying dynamics. We analyze the waiting-time distributions of high-frequency foreign exchange data for the best executable bid-ask prices across all major currencies. We find that the lognormal distribution yields a good overall fit for the waiting-time distribution between currency rate changes if both short and long waiting times are included. If we restrict our study to long waiting times, each currency pair’s distribution is consistent with a power-law tail with exponent near to 3.5. However, for short waiting times, the overall distribution resembles one generated by an archetypal complex systems model in which boundedly rational agents compete for limited resources. Our findings suggest that a gradual transition arises in trading behavior between a fast regime in which traders act in a boundedly rational way and a slower one in which traders’ decisions are driven by generic feedback mechanisms across multiple timescales and hence produce similar power-law tails irrespective of currency type.

  16. The sower’s way: quantifying the narrowing net-energy pathways to a global energy transition

    NASA Astrophysics Data System (ADS)

    Sgouridis, Sgouris; Csala, Denes; Bardi, Ugo

    2016-09-01

    Planning the appropriate renewable energy (RE) installation rate should balance two partially contradictory objectives: substituting fossil fuels fast enough to stave-off the worst consequences of climate change while maintaining a sufficient net energy flow to support the world’s economy. The upfront energy invested in constructing a RE infrastructure subtracts from the net energy available for societal energy needs, a fact typically neglected in energy projections. Modeling feasible energy transition pathways to provide different net energy levels we find that they are critically dependent on the fossil fuel emissions cap and phase-out profile and on the characteristic energy return on energy invested of the RE technologies. The easiest pathway requires installation of RE plants to accelerate from 0.12 TWp yr-1 in 2013 to peak between 7.3 and 11.6 TWp yr-1 in the late 2030s, for an early or a late fossil-fuel phase-out respectively in order for emissions to stay within the recommended CO2 budget.

  17. Global characterization of the oocyte-to-embryo transition in Caenorhabditis elegans uncovers a novel mRNA clearance mechanism.

    PubMed

    Stoeckius, Marlon; Grün, Dominic; Kirchner, Marieluise; Ayoub, Salah; Torti, Francesca; Piano, Fabio; Herzog, Margareta; Selbach, Matthias; Rajewsky, Nikolaus

    2014-08-18

    The oocyte-to-embryo transition (OET) is thought to be mainly driven by post-transcriptional gene regulation. However, expression of both RNAs and proteins during the OET has not been comprehensively assayed. Furthermore, specific molecular mechanisms that regulate gene expression during OET are largely unknown. Here, we quantify and analyze transcriptome-wide, expression of mRNAs and thousands of proteins in Caenorhabditis elegans oocytes, 1-cell, and 2-cell embryos. This represents a first comprehensive gene expression atlas during the OET in animals. We discovered a first wave of degradation in which thousands of mRNAs are cleared shortly after fertilization. Sequence analysis revealed a statistically highly significant presence of a polyC motif in the 3' untranslated regions of most of these degraded mRNAs. Transgenic reporter assays demonstrated that this polyC motif is required and sufficient for mRNA degradation after fertilization. We show that orthologs of human polyC-binding protein specifically bind this motif. Our data suggest a mechanism in which the polyC motif and binding partners direct degradation of maternal mRNAs. Our data also indicate that endogenous siRNAs but not miRNAs promote mRNA clearance during the OET.

  18. Global changes of the RNA-bound proteome during the maternal-to-zygotic transition in Drosophila

    PubMed Central

    Sysoev, Vasiliy O.; Fischer, Bernd; Frese, Christian K.; Gupta, Ishaan; Krijgsveld, Jeroen; Hentze, Matthias W.; Castello, Alfredo; Ephrussi, Anne

    2016-01-01

    The maternal-to-zygotic transition (MZT) is a process that occurs in animal embryos at the earliest developmental stages, during which maternally deposited mRNAs and other molecules are degraded and replaced by products of the zygotic genome. The zygotic genome is not activated immediately upon fertilization, and in the pre-MZT embryo post-transcriptional control by RNA-binding proteins (RBPs) orchestrates the first steps of development. To identify relevant Drosophila RBPs organism-wide, we refined the RNA interactome capture method for comparative analysis of the pre- and post-MZT embryos. We determine 523 proteins as high-confidence RBPs, half of which were not previously reported to bind RNA. Comparison of the RNA interactomes of pre- and post-MZT embryos reveals high dynamicity of the RNA-bound proteome during early development, and suggests active regulation of RNA binding of some RBPs. This resource provides unprecedented insight into the system of RBPs that govern the earliest steps of Drosophila development. PMID:27378189

  19. Pan-HER-An antibody mixture targeting EGFR, HER2 and HER3 abrogates preformed and ligand-induced EGFR homo- and heterodimers.

    PubMed

    Ellebaek, Sofie; Brix, Susanne; Grandal, Michael; Lantto, Johan; Horak, Ivan D; Kragh, Michael; Poulsen, Thomas Tuxen

    2016-11-01

    The human epidermal growth factor receptor (HER)-family is involved in development of many epithelial cancers. Therefore, HER-family members constitute important targets for anti-cancer therapeutics such as monoclonal antibodies (mAbs). A limitation to the success of single HER-targeting mAbs is development of acquired resistance through mechanisms such as alterted receptor dimerization patterns and dependencies. Pan-HER is a mixture of six mAbs simultaneously targeting epidermal growth factor receptor (EGFR), HER2 and HER3 with two mAbs against each receptor. Pan-HER has previously demonstrated broader efficacy than targeting single or dual receptor combinations also in resistant settings. In light of this broad efficacy, we decided to investigate the effect of Pan-HER compared with single HER-targeting with single and dual mAbs on HER-family cross-talk and dimerization focusing on EGFR. The effect of Pan-HER on cell proliferation and HER-family receptor degradation was superior to treatment with single mAbs targeting either single receptor, and similar to targeting a single receptor with two non-overlapping antibodies. Furthermore, changes in EGFR-dimerization patterns after treatment with Pan-HER were investigated by in situ proximity ligation assay and co-immunoprecipitation, demonstrating that Pan-HER and the EGFR-targeting mAb mixture efficiently down-regulate basal EGFR homo- and heterodimerization in two tested cell lines, whereas single mAbs had limited effects. Pan-HER and the EGFR-targeting mAb mixture also blocked EGF-binding and thereby ligand-induced changes in EGFR-dimerization levels. These results suggest that Pan-HER reduces the cellular capability to switch HER-dependency and dimerization pattern in response to treatment and thus hold promise for future clinical development of Pan-HER in resistant settings.

  20. Ligand-induced adhesion to activated endothelium and to vascular cell adhesion molecule-1 in lymphocytes transfected with the N-formyl peptide receptor.

    PubMed

    Honda, S; Campbell, J J; Andrew, D P; Engelhardt, B; Butcher, B A; Warnock, R A; Ye, R D; Butcher, E C

    1994-04-15

    Binding of FMLP to the neutrophil N-formyl peptide receptor (FPR) transmits signals through pertussis toxin-sensitive G proteins triggering Ca2+ flux, superoxide production, granule exocytosis, and neutrophil aggregation and adhesion involving the beta 2 (CD18) integrins. Expression of the FPR in mouse fibroblasts or human kidney cells has been shown to confer an N-formyl peptide-inducible Ca2+ flux in transfectants. Here we demonstrate that the transfected receptor can also support ligand-induced alterations in cellular adhesion. We established stable transfectants of mouse L1-2 pre-B cells with cDNA for human FPR (L1-2 FPR cells). The transfectants bind N-formyl-Nle-Leu-Phe-Nle-Tyr-Lys-fluorescein with 1.4 x 10(5) sites per cell and a dissociation constant of 3.3 nM. Stimulation with FMLP induces a transient Ca2+ flux. FMLP also triggers adhesion of L1-2 FPR cells to TNF-alpha- or LPS-activated bEnd3 cells (mouse brain-derived endothelial cells) and to purified mouse VCAM-1. Binding is inhibited by Abs to VCAM-1 and to the alpha-chain of its lymphocyte receptor (the alpha 4 beta 1 integrin, VLA-4). Stimulation with FMLP does not induce a change in cell surface expression of alpha 4. Induced adhesion to VCAM-1 is rapid, detectable at the earliest times measurable (30 to 60 s after FMLP addition), and is inhibited by pertussis toxin. We conclude that FPR can mediate integrin activation not only in neutrophils but also in lymphocytes, and can trigger rapid adhesion via lymphocyte alpha 4 beta 1. The adhesion of lymphocytes is critical to their migration and targeting; our results suggest the possibility of manipulating adhesive responses through expression of chemoattractant receptors in lymphoid cells engineered for cellular therapy, allowing targeted adhesion and potentially migration in response to locally administered ligands.

  1. Structure of the partially unliganded met state of 400 kDa hemoglobin: insights into ligand-induced structural changes of giant hemoglobins.

    PubMed

    Numoto, Nobutaka; Nakagawa, Taro; Kita, Akiko; Sasayama, Yuichi; Fukumori, Yoshihiro; Miki, Kunio

    2008-10-01

    Recent crystallographic studies have revealed the structures of some invertebrate extracellular giant hemoglobins of 3,600 kDa or 400 kDa and their common quaternary structure of dodecameric subassembly composed of four kinds of globin subunits (A1, A2, B1, and B2). These results have provided insight into the mechanisms of their unique functional properties of oxygen binding and sulfide binding. All of these structures were solved with oxygenated or CO-liganded forms at low or moderate resolutions. We have determined the crystal structure of 400 kDa Hb from a polychaete Oligobrachia mashikoi at 1.95 A resolution. The electron densities at higher resolution confirm the existence of an isoform of the B1 subunit because of the inconsistency with the model that was built from the formerly known amino acid sequence. The brownish color of the crystals used in this study and the absorption spectrum from the dissolved crystals strongly indicated that the obtained structure was a ferric met state, whereas complete absence of electron density around the distal heme pockets were observed at the A2, B1, and B2 subunits. We concluded that the obtained structure was in unliganded met forms at three of four globin subunits in the 24mer assembly and in oxygenated forms at the remaining A1 subunits. The partially unliganded structure showed remarkable structural changes at the AB loop regions causing quaternary rearrangements of the EF-dimer structure. In contrast, few changes occurred at the interface regions composed of the E and F helices. These results suggest that the ligand-induced structural changes of Oligobrachia Hb are quite different from those of the well-studied mollusk Hb having the same EF-dimer structure. The structural rearrangements make the dodecameric subassembly form a tighter conformation than those of fully oxygenated or CO-liganded dodecamer structure.

  2. Transition from control to elimination: impact of the 10-year global fund project on malaria control and elimination in China.

    PubMed

    Wang, Ru-Bo; Zhang, Qing-Feng; Zheng, Bin; Xia, Zhi-Gui; Zhou, Shui-Sen; Tang, Lin-Hua; Gao, Qi; Wang, Li-Ying; Wang, Rong-Rong

    2014-01-01

    The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM) supported a project on the control and elimination of malaria in People's Republic of China which was one of the biggest-scale international cooperation programmes to control malaria in the country during the past 10 years. The project promoted the effective implementation of the Chinese national malaria control programme. On the basis of epidemiologic data, an overview of the project activities and key performance indicators, the overall impact of the GFATM project was evaluated. We also reviewed relevant programme features including technological and management approaches, with a focus on best practice, innovations in implementation and the introduction of international standards. Last, we summarised the multi-stakeholder cooperation mechanism and comments on its sustainability in the post-GFATM period. Recommendations for the future management of the Chinese national malaria elimination programme are put forward after considering the challenges, shortcomings and lessons learnt during the implementation of the GFATM project in China to sustain past achievements and foster the attainment of the ultimate goal of malaria elimination for the country.

  3. Ligand-induced Epitope Masking

    PubMed Central

    Mould, A. Paul; Askari, Janet A.; Byron, Adam; Takada, Yoshikazu; Jowitt, Thomas A.; Humphries, Martin J.

    2016-01-01

    We previously demonstrated that Arg-Gly-Asp (RGD)-containing ligand-mimetic inhibitors of integrins are unable to dissociate pre-formed integrin-fibronectin complexes (IFCs). These observations suggested that amino acid residues involved in integrin-fibronectin binding become obscured in the ligand-occupied state. Because the epitopes of some function-blocking anti-integrin monoclonal antibodies (mAbs) lie near the ligand-binding pocket, it follows that the epitopes of these mAbs may become shielded in the ligand-occupied state. Here, we tested whether function-blocking mAbs directed against α5β1 can interact with the integrin after it forms a complex with an RGD-containing fragment of fibronectin. We showed that the anti-α5 subunit mAbs JBS5, SNAKA52, 16, and P1D6 failed to disrupt IFCs and hence appeared unable to bind to the ligand-occupied state. In contrast, the allosteric anti-β1 subunit mAbs 13, 4B4, and AIIB2 could dissociate IFCs and therefore were able to interact with the ligand-bound state. However, another class of function-blocking anti-β1 mAbs, exemplified by Lia1/2, could not disrupt IFCs. This second class of mAbs was also distinguished from 13, 4B4, and AIIB2 by their ability to induce homotypic cell aggregation. Although the epitope of Lia1/2 was closely overlapping with those of 13, 4B4, and AIIB2, it appeared to lie closer to the ligand-binding pocket. A new model of the α5β1-fibronectin complex supports our hypothesis that the epitopes of mAbs that fail to bind to the ligand-occupied state lie within, or very close to, the integrin-fibronectin interface. Importantly, our findings imply that the efficacy of some therapeutic anti-integrin mAbs could be limited by epitope masking. PMID:27484800

  4. High influx of carbon in walls of agglutinated foraminifers during the Permian-Triassic transition in global oceans

    USGS Publications Warehouse

    Nestell, Galina P.; Nestell, Merlynd K.; Ellwood, Brooks B.; Wardlaw, Bruce R.; Basu, Asish R.; Ghosh, Nilotpal; Phuong Lan, Luu Thi; Rowe, Harry D.; Hunt, Andrew G.; Tomkin, Jonathan H.; Ratcliffe, Kenneth T.

    2015-01-01

    The Permian–Triassic mass extinction is postulated to be related to the rapid volcanism that produced the Siberian flood basalt (Traps). Unrelated volcanic eruptions producing several episodes of ash falls synchronous with the Siberian Traps are found in South China and Australia. Such regional eruptions could have caused wildfires, burning of coal deposits, and the dispersion of coal fly ash. These eruptions introduced a major influx of carbon into the atmosphere and oceans that can be recognized in the wallstructure of foraminiferal tests present in survival populations in the boundary interval strata. Analysis of free specimens of foraminifers recovered from residues of conodont samples taken at aPermian–Triassic boundary section at Lung Cam in northern Vietnam has revealed the presence of a significant amount of elemental carbon, along with oxygen and silica, in their test wall structure, but an absence of calcium carbonate. These foraminifers, identified as Rectocornuspira kalhori, Cornuspira mahajeri, and Earlandia spp. and whose tests previously were considered to be calcareous, are confirmed to be agglutinated, and are now referred to as Ammodiscus kalhori and Hyperammina deformis. Measurement of the 207Pb/204Pb ratios in pyrite clusters attached to the foraminiferal tests confirmed that these tests inherited the Pb in their outer layer from carbon-contaminated seawater. We conclude that the source of the carbon could have been either global coal fly ash or forest fire-dispersed carbon, or a combination of both, that was dispersed into the Palaeo-Tethys Ocean immediately after the end-Permian extinction event.

  5. Global characteristics of the upper transition height derived from the topside Alouette/ISIS topside sounder electron density profiles, the Formosat-3/COSMIC density profiles and the IRI ion composition model

    NASA Astrophysics Data System (ADS)

    Truhlik, Vladimir; Triskova, Ludmila; Benson, Robert; Bilitza, Dieter; Chu, Philip; Richards, Phil G.; Wang, Yongli

    The upper transition height (Ht) (the altitude of the transition from heavy atomic ions to light ions or in the simplest form the transition from O+ to H+) is an important parameter, representing the boundary between the ionosphere and the plasmasphere. Ht is very sensitive to various geophysical parameters, like solar and magnetic activity and strongly depends on latitude and local time. There were numerous studies of this parameter in past decades. In spite of these efforts, no model satisfactorily represents this parameter so far. Moreover, surprising evidence of very low transition heights during the last prolonged solar minimum, of a level never obtained before, have been reported. We investigate the upper transition height on the global scale. We made progress in processing large data sets of Ht deduced from the Alouette/ISIS topside sounder and from the Formosat-3/COSMIC vertical electron-density profiles Ne(h) using the theoretical Global Plasma Ionosphere Density (GPID) model (Webb and Essex, 2004) and a revised non-linear function describing the scale height vs. altitude (Titheridge, 1976) to fit the vertical density profiles to the observed profiles and to determine the upper transition height. Since both methods require the plasma temperatures and their gradients as input, these are calculated using the IRI2012 model. Both methods are verified using a large amount of electron and ion density profiles simulated by the FLIP theoretical model and their accuracy is discussed. We compare the results from Alouette/ISIS and Formosat-3/COSMIC and present a global distribution of the calculated Ht and its dependence on geophysical parameters. Finally we compare it with Ht calculated using the IRI ion composition model. Titheridge, J.E., 1976. Ion Transition Heights from Topside Electron-Density Profiles. Planetary and Space Science 24 (3), 229-245. Webb, P.A., Essex, E.A., 2004. A dynamic global model of the plasmasphere. Journal of Atmospheric and Solar

  6. The Last Transition From Extreme Glacial to Extreme Interglacial Climate in NW Patagonia: Regional and Global Implications

    NASA Astrophysics Data System (ADS)

    Moreno, P. I.

    2004-12-01

    The study of interhemispheric climate linkages during and since the last ice age has benefited from the recent development of high-resolution ice core and marine records from the mid- and high latitudes of the Southern Hemisphere. Few paleoclimate records from terrestrial environments in these regions, however, have the temporal continuity, time resolution, and adequate chronologic control to allow a detailed examination of the timing, rates, direction, and phasing of climate change at millennial timescales. Stratigraphic, palynologic, and charcoal records from small, high-sediment accumulating lakes in the Chilean Lake District (41ºS) afford useful data for examining the interval between the LGM to the early Holocene (25-8 ka, ka=cal kyr BP). Millennial-scale changes in glacier extent and vegetation patterns within this interval match key events both in the Northern Hemisphere and Antarctic records, in particular the EPICA Dome C data, highlighting the role of an atmosphere-based conduit for the global propagation of abrupt climate changes. The onset of the last termination in NW Patagonia is marked by glacial collapse and the expansion of rainforest trees at 17.7 ka. An apparent antiphase relationship among the polar hemispheres between 17.7-14.7 ka, might reflect the hemispheric-scale effects of a quasi-total shut down of Atlantic Meridional Overturning circulation driven by Heinrich event 1. Extreme glacial and interglacial modes in the position/strength of the westerlies at multi-millennial timescales in the southern westerlies accompany important shifts in the abundance and composition of rainforest communities during the last termination and the early Holocene. At millennial timescales, this interval is characterised by successive warming pulses interrupted by a generalized reversal in trend with cooling events starting at 14.7 and 13.4 ka. Fires between 12.9-11.5 ka, i.e. Younger Dryas Chron (YDC), led to the expansion of opportunistic rainforest species

  7. Is the northern tethyan carbonate platform drowning D3 (Hauterivian-Barremian transition) related to a global event?

    NASA Astrophysics Data System (ADS)

    Bodin, S.; Godet, A.; Adatte, T.; Föllmi, K. B.

    2003-04-01

    platform development during this period, in wich we put emphasis on the temporal and spatial evolution of platform drowning (regional versus global event?), and on the mechanisms involved in drowning (sea level change, nutrients, temperature, paleo CO_2, etc.).

  8. A patient-derived, pan-cancer EMT signature identifies global molecular alterations and immune target enrichment following epithelial to mesenchymal transition

    PubMed Central

    Mak, Milena P.; Tong, Pan; Diao, Lixia; Cardnell, Robert J.; Gibbons, Don L.; William, William N.; Skoulidis, Ferdinandos; Parra, Edwin R.; Rodriguez-Canales, Jaime; Wistuba, Ignacio I.; Heymach, John V.; Weinstein, John N.; Coombes, Kevin R.; Wang, Jing; Byers, Lauren Averett

    2015-01-01

    Purpose We previously demonstrated the association between epithelial-to-mesenchymal transition (EMT) and drug response in lung cancer using an EMT signature derived in cancer cell lines. Given the contribution of tumor microenvironments to EMT, we extended our investigation of EMT to patient tumors from 11 cancer types to develop a pan-cancer EMT signature. Experimental Design Using the pan-cancer EMT signature, we conducted an integrated, global analysis of genomic and proteomic profiles associated with EMT across 1,934 tumors including breast, lung, colon, ovarian, and bladder cancers. Differences in outcome and in vitro drug response corresponding to expression of the pan-cancer EMT signature were also investigated. Results Compared to the lung cancer EMT signature, the patient-derived, pan-cancer EMT signature encompasses a set of core EMT genes that correlate even more strongly with known EMT markers across diverse tumor types and identifies differences in drug sensitivity and global molecular alterations at the DNA, RNA, and protein levels. Among those changes associated with EMT, pathway analysis revealed a strong correlation between EMT and immune activation. Further supervised analysis demonstrated high expression of immune checkpoints and other druggable immune targets such as PD1, PD-L1, CTLA4, OX40L, and PDL2, in tumors with the most mesenchymal EMT scores. Elevated PD-L1 protein expression in mesenchymal tumors was confirmed by immunohistochemistry in an independent lung cancer cohort. Conclusions This new signature provides a novel, patient-based, histology-independent tool for the investigation of EMT and offers insights into potential novel therapeutic targets for mesenchymal tumors, independent of cancer type, including immune checkpoints. PMID:26420858

  9. Pion-photon transition form factor using light-cone sum rules: theoretical results, expectations, and a global-data fit

    NASA Astrophysics Data System (ADS)

    Bakulev, A. P.; Mikhailov, S. V.; Pimikov, A. V.; Stefanis, N. G.

    2011-10-01

    A global fit to the data from different collaborations (CELLO, CLEO, BaBar) on the pion-photon transition form factor is carried out using light-cone sum rules. The analysis includes the next-to-leading QCD radiative corrections and the twist-four contributions, while the main next-to-next-to-leading term and the twist-six contribution are taken into account in the form of theoretical uncertainties. We use the information extracted from the data to investigate the pivotal characteristics of the pion distribution amplitude. This is done by dividing the data into two sets: one containing all data up to 9 GeV 2, whereas the other incorporates also the high- Q tail of the BaBar data. We find that it is not possible to accommodate into the fit these BaBar data points with the same accuracy and conclude that it is difficult to explain these data in the standard scheme of OCD.

  10. Global fit analysis of glucose binding curves reveals a minimal model for kinetic cooperativity in human glucokinase.

    PubMed

    Larion, Mioara; Miller, Brian G

    2010-10-19

    Human pancreatic glucokinase is a monomeric enzyme that displays kinetic cooperativity, a feature that facilitates enzyme-mediated regulation of blood glucose levels in the body. Two theoretical models have been proposed to describe the non-Michaelis-Menten behavior of human glucokinase. The mnemonic mechanism postulates the existence of one thermodynamically favored enzyme conformation in the absence of glucose, whereas the ligand-induced slow transition model (LIST) requires a preexisting equilibrium between two enzyme species that interconvert with a rate constant slower than turnover. To investigate whether either of these mechanisms is sufficient to describe glucokinase cooperativity, a transient-state kinetic analysis of glucose binding to the enzyme was undertaken. A complex, time-dependent change in enzyme intrinsic fluorescence was observed upon exposure to glucose, which is best described by an analytical solution comprised of the sum of four exponential terms. Transient-state glucose binding experiments conducted in the presence of increasing glycerol concentrations demonstrate that three of the observed rate constants decrease with increasing viscosity. Global fit analyses of experimental glucose binding curves are consistent with a kinetic model that is an extension of the LIST mechanism with a total of four glucose-bound binary complexes. The kinetic model presented herein suggests that glucokinase samples multiple conformations in the absence of ligand and that this conformational heterogeneity persists even after the enzyme associates with glucose.

  11. Use of surface plasmon resonance for real-time measurements of the global conformational transition in human phenylalanine hydroxylase in response to substrate binding and catalytic activation.

    PubMed

    Flatmark, T; Stokka, A J; Berge, S V

    2001-07-15

    In the present study the optical biosensor technique, based on the surface plasmon resonance (SPR) phenomenon, was used for real-time measurements of the reversible binding of the pterin cofactor (6R)-l-erythro-5,6,7,8-tetrahydrobiopterin (BH(4)) and l-phenylalanine (l-Phe) to human phenylalanine hydroxylase (hPAH). When BH(4) (241 Da) was injected over the sensor chip with immobilized tetrameric wt-hPAH a positive DeltaRU response was observed with a square-wave type of sensorgram and a saturable response (about 25 RU/(pmol subunit/mm(2)) with a [S](0.5) value of 5.6 +/- 0.8 microM for the pterin cofactor. The rapid on-and-off rates were, however, not possible to determine. By contrast, when l-Phe (165 Da) was injected a time-dependent increase in RU (up to about 3 min) and a much higher saturable DeltaRU response (about 75 RU/(pmol subunit/mm(2)) at 2 mM l-Phe) than expected (i.e., <5 RU/(pmol subunit/mm(2))) from the low molecular mass of l-Phe were observed in the sensorgram. The half-time for the on-and-off rates were 6 +/- 2 and 9 +/- 1 s, respectively, at 2 mM l-Phe. The steady-state (apparent equilibrium) response revealed a hyperbolic concentration dependence with a [S](0.5) value of 98 +/- 7 microM. The [S](0.5) values of both pterin cofactor and l-Phe were lower than those determined by steady-state enzyme kinetic analysis. Evidence is presented that the DeltaRU response to l-Phe is accounted for by the global conformational transition which occurs in the enzyme upon l-Phe binding, i.e., by the slow reversible transition from a low activity state ("T"-state) to a high activity state ("R"-state) characteristic of this hysteretic enzyme.

  12. In Bacillus subtilis LutR is part of the global complex regulatory network governing the adaptation to the transition from exponential growth to stationary phase.

    PubMed

    Irigül-Sönmez, Öykü; Köroğlu, Türkan E; Öztürk, Büşra; Kovács, Ákos T; Kuipers, Oscar P; Yazgan-Karataş, Ayten

    2014-02-01

    The lutR gene, encoding a product resembling a GntR-family transcriptional regulator, has previously been identified as a gene required for the production of the dipeptide antibiotic bacilysin in Bacillus subtilis. To understand the broader regulatory roles of LutR in B. subtilis, we studied the genome-wide effects of a lutR null mutation by combining transcriptional profiling studies using DNA microarrays, reverse transcription quantitative PCR, lacZ fusion analyses and gel mobility shift assays. We report that 65 transcriptional units corresponding to 23 mono-cistronic units and 42 operons show altered expression levels in lutR mutant cells, as compared with lutR(+) wild-type cells in early stationary phase. Among these, 11 single genes and 25 operons are likely to be under direct control of LutR. The products of these genes are involved in a variety of physiological processes associated with the onset of stationary phase in B. subtilis, including degradative enzyme production, antibiotic production and resistance, carbohydrate utilization and transport, nitrogen metabolism, phosphate uptake, fatty acid and phospholipid biosynthesis, protein synthesis and translocation, cell-wall metabolism, energy production, transfer of mobile genetic elements, induction of phage-related genes, sporulation, delay of sporulation and cannibalism, and biofilm formation. Furthermore, an electrophoretic mobility shift assay performed in the presence of both SinR and LutR revealed a close overlap between the LutR and SinR targets. Our data also revealed a significant overlap with the AbrB regulon. Together, these findings reveal that LutR is part of the global complex, interconnected regulatory systems governing adaptation of bacteria to the transition from exponential growth to stationary phase.

  13. Emergent Self-Organized Criticality in Gene Expression Dynamics: Temporal Development of Global Phase Transition Revealed in a Cancer Cell Line

    PubMed Central

    Tsuchiya, Masa; Giuliani, Alessandro; Hashimoto, Midori; Erenpreisa, Jekaterina; Yoshikawa, Kenichi

    2015-01-01

    Background The underlying mechanism of dynamic control of the genome-wide expression is a fundamental issue in bioscience. We addressed it in terms of phase transition by a systemic approach based on both density analysis and characteristics of temporal fluctuation for the time-course mRNA expression in differentiating MCF-7 breast cancer cells. Methodology In a recent work, we suggested criticality as an essential aspect of dynamic control of genome-wide gene expression. Criticality was evident by a unimodal-bimodal transition through flattened unimodal expression profile. The flatness on the transition suggests the existence of a critical transition at which up- and down-regulated expression is balanced. Mean field (averaging) behavior of mRNAs based on the temporal expression changes reveals a sandpile type of transition in the flattened profile. Furthermore, around the transition, a self-similar unimodal-bimodal transition of the whole expression occurs in the density profile of an ensemble of mRNA expression. These singular and scaling behaviors identify the transition as the expression phase transition driven by self-organized criticality (SOC). Principal Findings Emergent properties of SOC through a mean field approach are revealed: i) SOC, as a form of genomic phase transition, consolidates distinct critical states of expression, ii) Coupling of coherent stochastic oscillations between critical states on different time-scales gives rise to SOC, and iii) Specific gene clusters (barcode genes) ranging in size from kbp to Mbp reveal similar SOC to genome-wide mRNA expression and ON-OFF synchronization to critical states. This suggests that the cooperative gene regulation of topological genome sub-units is mediated by the coherent phase transitions of megadomain-scaled conformations between compact and swollen chromatin states. Conclusion and Significance In summary, our study provides not only a systemic method to demonstrate SOC in whole-genome expression

  14. Presenilin mediates neuroprotective functions of ephrinB and brain-derived neurotrophic factor and regulates ligand-induced internalization and metabolism of EphB2 and TrkB receptors.

    PubMed

    Barthet, Gael; Dunys, Julie; Shao, Zhiping; Xuan, Zhao; Ren, Yimin; Xu, Jindong; Arbez, Nicolas; Mauger, Gweltas; Bruban, Julien; Georgakopoulos, Anastasios; Shioi, Junichi; Robakis, Nikolaos K

    2013-02-01

    Activation of EphB receptors by ephrinB (efnB) ligands on neuronal cell surface regulates important functions, including neurite outgrowth, axonal guidance, and synaptic plasticity. Here, we show that efnB rescues primary cortical neuronal cultures from necrotic cell death induced by glutamate excitotoxicity and that this function depends on EphB receptors. Importantly, the neuroprotective function of the efnB/EphB system depends on presenilin 1 (PS1), a protein that plays crucial roles in Alzheimer's disease (AD) neurodegeneration. Furthermore, absence of one PS1 allele results in significantly decreased neuroprotection, indicating that both PS1 alleles are necessary for full expression of the neuroprotective activity of the efnB/EphB system. We also show that the ability of brain-derived neurotrophic factor (BDNF) to protect neuronal cultures from glutamate-induced cell death depends on PS1. Neuroprotective functions of both efnB and BDNF, however, were independent of γ-secretase activity. Absence of PS1 decreases cell surface expression of neuronal TrkB and EphB2 without affecting total cellular levels of the receptors. Furthermore, PS1-knockout neurons show defective ligand-dependent internalization and decreased ligand-induced degradation of TrkB and Eph receptors. Our data show that PS1 mediates the neuroprotective activities of efnB and BDNF against excitotoxicity and regulates surface expression and ligand-induced metabolism of their cognate receptors. Together, our observations indicate that PS1 promotes neuronal survival by regulating neuroprotective functions of ligand-receptor systems.

  15. Globalization, global health, and access to healthcare.

    PubMed

    Collins, Téa

    2003-01-01

    It is now commonly realized that the globalization of the world economy is shaping the patterns of global health, and that associated morbidity and mortality is affecting countries' ability to achieve economic growth. The globalization of public health has important implications for access to essential healthcare. The rise of inequalities among and within countries negatively affects access to healthcare. Poor people use healthcare services less frequently when sick than do the rich. The negative impact of globalization on access to healthcare is particularly well demonstrated in countries of transitional economies. No longer protected by a centralized health sector that provided free universal access to services for everyone, large segments of the populations in the transition period found themselves denied even the most basic medical services. Only countries where regulatory institutions are strong, domestic markets are competitive and social safety nets are in place, have a good chance to enjoy the health benefits of globalization.

  16. The Hetu'u Global Network: Using the rare June 5th/6th Transit of Venus to Bring Astronomy to the Remote Easter Island

    NASA Astrophysics Data System (ADS)

    Faherty, Jacqueline; Rodriguez, D.

    2013-01-01

    There are rare times in astronomy when a celestial event, visible in broad daylight, can be used to measure a fundamental parameter and inspire a globe full of school age students. The June 5th/6th transit of Venus was one such event. In celebration, nine astronomy postdocs from the Chilean mainland traveled to Easter Island to lead a series of astronomy outreach activities over three days, culminating in a transit-viewing event. Our team dubbed "Equipo Hetu'u" or "Team Star" in the Rapa Nui (Easter Island native) language spent two days giving astronomy talks and doing hands-on demonstrations at the Museo Antropologico P. Sebastian Englert. In the final day-and-a-half leading up to the transit, we visited the science classes in the majority of the schools on the island, in order to spread the message about the once-in-a-lifetime transit event, highlighting how we planned on using it to measure the distance to the Sun. We estimate over 25% 1500 people) of this remote island participated in one or more of our organized activities. Our experience with this project is an excellent lesson on how to organize, lead, and fully execute a major outreach endeavor that inspires hundreds with minimal resources (save the spectacular event provided by the cosmos).

  17. The abrupt climate change near 4,400 yr BP on the cultural transition in Yuchisi, China and its global linkage

    NASA Astrophysics Data System (ADS)

    Wang, Jianjun; Sun, Liguang; Chen, Liqi; Xu, Libin; Wang, Yuhong; Wang, Xinming

    2016-06-01

    Extreme climatic events have profound impacts on human society. Here we present the results of a study of organic biomarkers within a sedimentary section at the archaeological site of Yuchisi, eastern China, in order to reconstruct climatic variability during the Dawenkou (5,050–4,400 yr BP) and Longshan (4,400–4,000 yr BP) cultures. At ~4,400 yr BP, within the cultural transition horizon, abrupt changes in biomarkers, such as the fatty acid ratio C18:2/C18:0, 2C31/(C27 + C29), n-C18-ol and n-C30-ol, indicate the occurrence of local climate changes over the course of a few decades. These changes occurred during the transition from the Holocene warm period to a subsequent cold period which lasted for the following 600 years. This climatic shift has been recorded at numerous sites worldwide, and it is likely to have been the main cause of the widespread collapse of many isolated cultures at that time. The palaeoclimatic and archaeological data from the Yuchisi sediments may provide new insights into the relationship between climate change and prehistoric cultural transitions.

  18. The abrupt climate change near 4,400 yr BP on the cultural transition in Yuchisi, China and its global linkage

    PubMed Central

    Wang, Jianjun; Sun, Liguang; Chen, Liqi; Xu, Libin; Wang, Yuhong; Wang, Xinming

    2016-01-01

    Extreme climatic events have profound impacts on human society. Here we present the results of a study of organic biomarkers within a sedimentary section at the archaeological site of Yuchisi, eastern China, in order to reconstruct climatic variability during the Dawenkou (5,050–4,400 yr BP) and Longshan (4,400–4,000 yr BP) cultures. At ~4,400 yr BP, within the cultural transition horizon, abrupt changes in biomarkers, such as the fatty acid ratio C18:2/C18:0, 2C31/(C27 + C29), n-C18-ol and n-C30-ol, indicate the occurrence of local climate changes over the course of a few decades. These changes occurred during the transition from the Holocene warm period to a subsequent cold period which lasted for the following 600 years. This climatic shift has been recorded at numerous sites worldwide, and it is likely to have been the main cause of the widespread collapse of many isolated cultures at that time. The palaeoclimatic and archaeological data from the Yuchisi sediments may provide new insights into the relationship between climate change and prehistoric cultural transitions. PMID:27283832

  19. The Properties of XO-5b and WASP-82b Redetermined Using New High-Precision Transit Photometry and Global Data Analyses

    NASA Astrophysics Data System (ADS)

    Smith, A. M. S.

    2015-03-01

    This paper presents new transit photometry from the Isaac Newton Telescope of two transiting exoplanetary systems, XO-5 and WASP-82. In each case the new transit light curve is more precise than any other of that system previously published. The new data are analyzed alongside previously-published photometry and radial velocities, resulting in an improved orbital ephemeris and a refined set of system parameters in each case. The observational baseline of XO-5 is extended by very nearly four years, resulting in a determination of the orbital period of XO-5b to a precision of just 50 ms. The mass and radius of XO-5b are 1.19±0.03 and 1.14±0.03 times those of Jupiter, respectively. The light curve of WASP-82 is only the second published for this system. The planetary mass is 1.25±0.05 MJup, and the radius is 1.71±0.08 RJup.

  20. Global Transcriptome Profiling of Developing Leaf and Shoot Apices Reveals Distinct Genetic and Environmental Control of Floral Transition and Inflorescence Development in Barley[OPEN

    PubMed Central

    2015-01-01

    Timing of the floral transition and inflorescence development strongly affect yield in barley (Hordeum vulgare). Therefore, we examined the effects of daylength and the photoperiod response gene PHOTOPERIOD1 (Ppd-H1) on barley development and analyzed gene expression changes in the developing leaves and main shoot apices (MSAs) of barley by RNA sequencing. The daylength sensitivity of MSA development had two phases, floret primordia initiated under long and short days, whereas successful inflorescence development occurred only under long days. The transcripts associated with floral transition were largely regulated independently of photoperiod and allelic variation at Ppd-H1. The photoperiod- and Ppd-H1-dependent differences in inflorescence development and flower fertility were associated with the induction of barley FLOWERING LOCUS T orthologs: FT1 in leaves and FT2 in MSAs. FT1 expression was coregulated with transcripts involved in nutrient transport, carbohydrate metabolism, and cell cycle regulation, suggesting that FT1 might alter source-sink relationships. Successful inflorescence development correlated with upregulation of FT2 and transcripts related to floral organ development, phytohormones, and cell cycle regulation. Identification of photoperiod and stage-specific transcripts gives insights into the regulation of reproductive development in barley and provides a resource for investigation of the complexities of development and yield in temperate grasses. PMID:26307377

  1. Global Transcriptome Profiling of Developing Leaf and Shoot Apices Reveals Distinct Genetic and Environmental Control of Floral Transition and Inflorescence Development in Barley.

    PubMed

    Digel, Benedikt; Pankin, Artem; von Korff, Maria

    2015-09-01

    Timing of the floral transition and inflorescence development strongly affect yield in barley (Hordeum vulgare). Therefore, we examined the effects of daylength and the photoperiod response gene PHOTOPERIOD1 (Ppd-H1) on barley development and analyzed gene expression changes in the developing leaves and main shoot apices (MSAs) of barley by RNA sequencing. The daylength sensitivity of MSA development had two phases, floret primordia initiated under long and short days, whereas successful inflorescence development occurred only under long days. The transcripts associated with floral transition were largely regulated independently of photoperiod and allelic variation at Ppd-H1. The photoperiod- and Ppd-H1-dependent differences in inflorescence development and flower fertility were associated with the induction of barley FLOWERING LOCUS T orthologs: FT1 in leaves and FT2 in MSAs. FT1 expression was coregulated with transcripts involved in nutrient transport, carbohydrate metabolism, and cell cycle regulation, suggesting that FT1 might alter source-sink relationships. Successful inflorescence development correlated with upregulation of FT2 and transcripts related to floral organ development, phytohormones, and cell cycle regulation. Identification of photoperiod and stage-specific transcripts gives insights into the regulation of reproductive development in barley and provides a resource for investigation of the complexities of development and yield in temperate grasses.

  2. Transition Planning

    ERIC Educational Resources Information Center

    Statfeld, Jenna L.

    2011-01-01

    Post-school transition is the movement of a child with disabilities from school to activities that occur after the completion of school. This paper provides information about: (1) post-school transition; (2) transition plan; (3) transition services; (4) transition planning; (5) vocational rehabilitation services; (6) services that are available…

  3. Harmonization of Land-Use Scenarios for the Period 1500-2100: 600 Years of Global Gridded Annual Land-Use Transitions, Wood Harvest, and Resulting Secondary Lands

    SciTech Connect

    Hurtt, George; Chini, Louise Parsons; Frolking, Steve; Betts, Richard; Feddema, Johannes; Fischer, Gavin M.; Fisk, J.P.; Hibbard, Kathleen A.; Houghton, R. A.; Janetos, Anthony C.; Jones, C.; Kindermann, G.; Kinoshita, Tsuguki; Goldeweijk, Kees K.; Riahi, Keywan; Shevliakova, Elena; Smith, Steven J.; Stehfest, Eike; Thomson, Allison M.; Thornton, P.; Van Vuuren, Detlef; Wang, Y.

    2011-08-08

    In preparation for the fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC), the international community is developing new advanced Earth System Models (ESM) to assess the combined effects of human activities (e.g. land use and fossil fuel emissions) on the carbon-climate system. In addition, four Representative Concentration Pathway (RCP) scenarios of the future (2005-2100) are being provided by four Integrated Assessment Model (IAM) teams to be used as input to the ESMs for future carbon-climate projections (Moss et al., 2010). The diversity of approaches and requirements among IAMs and ESMs for tracking land-use change, along with the dependence of model projections on land-use history, presents a challenge for effectively passing data between these communities and for smoothly transitioning from the historical estimates to future projections. Here, a harmonized set of land-use scenarios are presented that smoothly connects historical reconstructions of land use with future projections, in the format required by ESMs.

  4. Transitions in sandflat biota since the 1930s: effects of sea-level rise, eutrophication and biological globalization in the tidal bay Königshafen, northern Wadden Sea

    NASA Astrophysics Data System (ADS)

    Schumacher, Juliane; Dolch, Tobias; Reise, Karsten

    2014-06-01

    Conspicuous macrozoobenthos and vegetation of intertidal sandflats in Königshafen (Island of Sylt, SE North Sea) were mapped in 1932, 1988 and 2008. Higher water levels since the 1930s with a concomitant increase in tidal dynamics are assumed to have weakened sediment stability. This dissolved the distinctly banded macrobenthic zonation of the 1930s. Near high water level, cyanobacterial mats with associated beetles, belts of the mudshrimp Corophium volutator and the seagrass Zostera noltii have vanished, while the range of the lugworm Arenicola marina has extended towards the shore. Near low water level, sandy elevations have become permanently submerged because a tidal creek has widened its bed. In 1988, extensive green algal mats and the almost complete absence of seagrass are attributed to peak eutrophication. This partially reversed until 2008. The mussel Mytilus edulis had strongly extended its beds along the creek in 1988. These were taken over by introduced Pacific oysters Crassostrea gigas in 2008. Also in 2008, the cordgrass Spartina anglica, another introduced species, grew into large tussocks where cyanobacterial mats and a Corophium-belt had been mapped in the 1930s. Former benthic patterns may have little chance of resurrection by conventional nature protection because these small-scale shifts represent responses to regional and global change.

  5. Oncogenic RAS alters the global and gene-specific histone modification pattern during epithelial-mesenchymal transition in colorectal carcinoma cells.

    PubMed

    Peláez, Ignacio Mazón; Kalogeropoulou, Margarita; Ferraro, Angelo; Voulgari, Angeliki; Pankotai, Tibor; Boros, Imre; Pintzas, Alexander

    2010-06-01

    The presence of different forms of histone covalent modifications, such as phosphorylation, acetylation and methylation in localized promoter regions are markers for chromatin packing and transcription. Activation of RAS signalling pathways through oncogenic RAS mutations is a hallmark of colorectal cancer. Overexpression of Harvey-Ras oncogene induces epithelial-mesenchymal transition (EMT) in Caco-2 cells. We focused on the role of epigenetic modifications of histone H3 and its dependence on RAS signal transduction pathways and oncogenic transformation. Using cell lines stably overexpressing oncogenic Harvey-RAS with EMT phenotype, we studied the acquired changes in the H3 histone modification patterns. Two genes show inverse protein expression patterns after Ha-RAS overexpression: Cyclin D1, a cell cycle-related gene, and the EMT marker-gene E-cadherin. We report that these two genes demonstrate matching inverse histone repression patterns on their promoter, while histone markers associated with an active state of genes were affected by the RAS-activated signalling pathway MEK-ERK-MSK1. Furthermore, we show that though the level of methyltransferases enzymes was increased, the status of H3 three-methylation at lysine 27 (H3K27me(3)), associated with gene repression on the promoter of Cyclin D1, was lower. Together, these results suggest that histone covalent modifications can be affected by oncogenic RAS pathways to regulate the expression of target genes like Cyclin D1 or E-cadherin and that the dynamic balance of opposing histone-modifying enzymes is critical for the regulation of cell proliferation.

  6. How severe is the modern biotic crisis?—A comparison of global change and biotic crisis between Permian-Triassic transition and modern times

    NASA Astrophysics Data System (ADS)

    Yin, Hongfu; He, Weihong; Xie, Shucheng

    2011-03-01

    A comparison of the modern condition with the Permian-Triassic Boundary (PTB) times was made to estimate how severe the modern biotic crisis is. About the global changes, the two periods are correlative in carbon dioxide concentration and carbon isotope negative excursion, UV strengthening, temperature increase, ocean acidification, and weathering enhancement. The following tendencies of biotic crises are also correlative: acceleration of extinction rates accompanied by parabolic curve of extinction with a turning interval representing the critical crisis; decline of the three main ecosystems: reefs, tropical rain forests and marine phytoplankton. It is also interesting to note that certain leading organism in both periods undergo accelerated evolution during the crisis. The comparison shows that the modern crisis is about at the turning point from decline to decimation. The extinction curve is now parabolic, and the extinction rate has been accelerated, but the decimation is not yet in real. This is also justified by the modern situation of the three main ecosystems. Modern biotic decline may worsen into decimation and mass extinction but may also get better and recover to ordinary evolution. Since human activities are the main cause of the deterioration of environments and organisms, mankind should be responsible and able to strive for the recovery of the crisis. For the future of mankind, Homo sapiens may become extinct, i.e., disappear without leaving descendants, or evolve into a new and more advanced species, i.e., disappear but leave descendants. For a better future, mankind should be conscious of the facing danger and act as a whole to save biodiversity and harmonize with the environments.

  7. Xbp1 Directs Global Repression of Budding Yeast Transcription during the Transition to Quiescence and Is Important for the Longevity and Reversibility of the Quiescent State

    PubMed Central

    Miles, Shawna; Li, Lihong; Davison, Jerry; Breeden, Linda L.

    2013-01-01

    Pure populations of quiescent yeast can be obtained from stationary phase cultures that have ceased proliferation after exhausting glucose and other carbon sources from their environment. They are uniformly arrested in the G1 phase of the cell cycle, and display very high thermo-tolerance and longevity. We find that G1 arrest is initiated before all the glucose has been scavenged from the media. Maintaining G1 arrest requires transcriptional repression of the G1 cyclin, CLN3, by Xbp1. Xbp1 is induced as glucose is depleted and it is among the most abundant transcripts in quiescent cells. Xbp1 binds and represses CLN3 transcription and in the absence of Xbp1, or with extra copies of CLN3, cells undergo ectopic divisions and produce very small cells. The Rad53-mediated replication stress checkpoint reinforces the arrest and becomes essential when Cln3 is overproduced. The XBP1 transcript also undergoes metabolic oscillations under glucose limitation and we identified many additional transcripts that oscillate out of phase with XBP1 and have Xbp1 binding sites in their promoters. Further global analysis revealed that Xbp1 represses 15% of all yeast genes as they enter the quiescent state and over 500 of these transcripts contain Xbp1 binding sites in their promoters. Xbp1-repressed transcripts are highly enriched for genes involved in the regulation of cell growth, cell division and metabolism. Failure to repress some or all of these targets leads xbp1 cells to enter a permanent arrest or senescence with a shortened lifespan. PMID:24204289

  8. Ligand inducible assembly of a DNA tetrahedron.

    PubMed

    Dohno, Chikara; Atsumi, Hiroshi; Nakatani, Kazuhiko

    2011-03-28

    Here we show that a small synthetic ligand can be used as a key building component for DNA nanofabrication. Using naphthyridinecarbamate dimer (NCD) as a molecular glue for DNA hybridization, we demonstrate NCD-triggered formation of a DNA tetrahedron.

  9. Transitional changes in microfossil assemblages in the Japan Sea from the Late Pliocene to Early Pleistocene related to global climatic and local tectonic events

    NASA Astrophysics Data System (ADS)

    Itaki, Takuya

    2016-12-01

    Many micropaleontological studies based on data from on-land sections, oil wells, and deep-sea drilling cores have provided important information about environmental changes in the Japan Sea that are related to the global climate and the local tectonics of the Japanese Islands. Here, major changes in the microfossil assemblages during the Late Pliocene to Early Pleistocene are reviewed. Late Pliocene (3.5-2.7 Ma) surface-water assemblages were characterized mainly by cold-temperate planktonic flora and fauna (nannofossils, diatoms, radiolarians, and planktonic foraminifera), suggesting that nutrient-rich North Pacific surface waters entered the Japan Sea via northern straits. The common occurrence of Pacific-type deep-water radiolarians during this period also suggests that deep water from the North Pacific entered the Japan Sea via the northern straits, indicating a sill depth >500 m. A weak warm-water influence is recognized along the Japanese coast, suggesting a small inflow of warm water via a southern strait. Nannofossil and sublittoral ostracod assemblages record an abrupt cooling event at 2.75 Ma that correlates with the onset of the Northern Hemisphere glaciation. Subsequently, cold intermediate- and deep-water assemblages of ostracods and radiolarians increased in abundance, suggesting active ventilation and the formation of the Japan Sea Proper Water, associated with a strengthened winter monsoon. Pacific-type deep-water radiolarians also disappeared around 2.75 Ma, which is attributed to the intermittent occurrence of deep anoxic environments and limited migration from the North Pacific, resulting from the near-closure or shallowing of the northern strait by a eustatic fall in sea level and tectonic uplift of northeastern Japan. A notable reduction in primary productivity from 2.3 to 1.3 Ma also suggests that the nutrient supply from the North Pacific was restricted by the near-closure of the northern strait. An increase in the abundance of subtropical

  10. Focusing on the Interfaces, Estuaries and Redox Transition Zones, for Understanding the Microbial Processes and Biogeochemical Cycling of Carbon under the Looming Influence of Global Warming and Anthropogenic Perturbations

    NASA Astrophysics Data System (ADS)

    Dang, H.; Jiao, N.

    2013-12-01

    the phytoplankton, zooplankton and fish communities in major world estuaries and coastal oceans. However, due to the rapid evolution rate and high adaptive nature of environmental microorganisms, global warming and anthropogenic perturbations may change the structure and function of the aquatic microbial communities. The estuarine redox transition zones may harbor diverse and novel microbial function groups and communities. How the different microbial processes may influence the ecological functionality and efficiency of estuarine ecosystems needs to be thoroughly investigated to be fully understood.

  11. Work transitions.

    PubMed

    Fouad, Nadya A; Bynner, John

    2008-01-01

    Individuals make choices in, and adjust to, a world of work that is often a moving target. Because work is so central to human functioning, and transitions in and out of work can have major mental health repercussions, the authors argue that applied psychologists in health services need to understand those transitions. This article focuses on the different types of transition throughout a person's working life and the resources needed at different stages to ensure the success of these transitions. The authors start by examining the roles of capability and adaptability in supporting and facilitating adjustment to work transitions and their relation to identity development. They then examine the role of social and institutional contexts in shaping work transitions and their outcomes. The authors focus on voluntary versus involuntary transitions and then broaden the lens in discussing the policy implications of research on work transitions.

  12. Pivotal Transitions - Historical and Today

    NASA Astrophysics Data System (ADS)

    Hurley, M.

    2008-08-01

    The goal of this paper is to enable readers to better "design" successful transitions that move Science and Technology or Research and Development (S&T/R&D) technologies and systems into operational capabilities for users. Transitions from S&T/R&D into acquisition and operations are challenging and critical to providing capab ilities to end users. Two historical examples, the Global Positioning System (GPS) and the Disaster Monitoring Constellation (DMC), are explored. Two current examples are also explored, including one from Operationally Responsive Space (ORS) which is in th e early stages of transition. While transitions are necessary, transition periods are inherently challenging and dynamically changing situations. These situations must be carefully managed and led in order to succeed. Characteristics, approaches, and incentives that foster effective transitions are discussed. Understanding the transition process and the communities involved allows one to maximize the chance of successfully moving an S&T/R&D development into an operational capability supporting end users.

  13. Transition to new global standards on hold.

    PubMed

    St George, J

    1995-01-01

    The nation's major standard-setting body for health care financial transactions has delayed a decision on migrating to new, international standards. An immediate move to EDIFACT standards would have been a setback for efforts to encourage the use of standards-based EDI.

  14. Microscopic Description of Nuclear Quantum Phase Transitions

    SciTech Connect

    Niksic, T.; Vretenar, D.; Lalazissis, G. A.; Ring, P.

    2007-08-31

    The relativistic mean-field framework, extended to include correlations related to restoration of broken symmetries and to fluctuations of the quadrupole deformation, is applied to a study of shape transitions in Nd isotopes. It is demonstrated that the microscopic self-consistent approach, based on global effective interactions, can describe not only general features of transitions between spherical and deformed nuclei, but also the singular properties of excitation spectra and transition rates at the critical point of quantum shape phase transition.

  15. Transitional Care

    ERIC Educational Resources Information Center

    Naylor, Mary; Keating, Stacen A.

    2008-01-01

    Transitional care encompasses a broad range of services and environments designed to promote the safe and timely passage of patients between levels of health care and across care settings. High-quality transitional care is especially important for older adults with multiple chronic conditions and complex therapeutic regimens, as well as for their…

  16. Global Education.

    ERIC Educational Resources Information Center

    Berkley, June, Ed.

    1982-01-01

    The articles in this collection deal with various methods of global education--education to prepare students to function as understanding and informed citizens of the world. Topics discussed in the 26 articles include: (1) the necessity of global education; (2) global education in the elementary school language arts curriculum; (3) science fiction…

  17. Global HRD.

    ERIC Educational Resources Information Center

    1997

    This document contains four papers from a symposium on global human resource development (HRD). "Globalization of Human Resource Management (HRM) in Government: A Cross-Cultural Perspective" (Pan Suk Kim) relates HRM to national cultures and addresses its specific functional aspects with a unique dimension in a global organization.…

  18. Global, regional, and national disability-adjusted life years (DALYs) for 306 diseases and injuries and healthy life expectancy (HALE) for 188 countries, 1990–2013: quantifying the epidemiological transition

    PubMed Central

    2015-01-01

    Summary Background The Global Burden of Disease Study 2013 (GBD 2013) aims to bring together all available epidemiological data using a coherent measurement framework, standardised estimation methods, and transparent data sources to enable comparisons of health loss over time and across causes, age–sex groups, and countries. The GBD can be used to generate summary measures such as disability-adjusted life-years (DALYs) and healthy life expectancy (HALE) that make possible comparative assessments of broad epidemiological patterns across countries and time. These summary measures can also be used to quantify the component of variation in epidemiology that is related to sociodemographic development. Methods We used the published GBD 2013 data for age-specific mortality, years of life lost due to premature mortality (YLLs), and years lived with disability (YLDs) to calculate DALYs and HALE for 1990, 1995, 2000, 2005, 2010, and 2013 for 188 countries. We calculated HALE using the Sullivan method; 95% uncertainty intervals (UIs) represent uncertainty in age-specific death rates and YLDs per person for each country, age, sex, and year. We estimated DALYs for 306 causes for each country as the sum of YLLs and YLDs; 95% UIs represent uncertainty in YLL and YLD rates. We quantified patterns of the epidemiological transition with a composite indicator of sociodemographic status, which we constructed from income per person, average years of schooling after age 15 years, and the total fertility rate and mean age of the population. We applied hierarchical regression to DALY rates by cause across countries to decompose variance related to the sociodemographic status variable, country, and time. Findings Worldwide, from 1990 to 2013, life expectancy at birth rose by 6·2 years (95% UI 5·6–6·6), from 65·3 years (65·0–65·6) in 1990 to 71·5 years (71·0–71·9) in 2013, HALE at birth rose by 5·4 years (4·9–5·8), from 56·9 years (54·5–59·1) to 62·3 years (59·7

  19. Transition metals

    PubMed Central

    Rodrigo-Moreno, Ana; Poschenrieder, Charlotte; Shabala, Sergey

    2013-01-01

    Transition metals such as Iron (Fe) and Copper (Cu) are essential for plant cell development. At the same time, due their capability to generate hydroxyl radicals they can be potentially toxic to plant metabolism. Recent works on hydroxyl-radical activation of ion transporters suggest that hydroxyl radicals generated by transition metals could play an important role in plant growth and adaptation to imbalanced environments. In this mini-review, the relation between transition metals uptake and utilization and oxidative stress-activated ion transport in plant cells is analyzed, and a new model depicting both apoplastic and cytosolic mode of ROS signaling to plasma membrane transporters is suggested. PMID:23333964

  20. Global Composite

    Atmospheric Science Data Center

    2013-04-19

    ... cover from one day to another. The lower panel is a composite in which red, green, and blue radiances from MISR's 70-degree ... In relatively clear ocean areas, the oblique-angle composite is generally brighter than its nadir counterpart due to enhanced ... Mar 2002 Images:  Global Composite location:  Global Images thumbnail:  ...

  1. Presidential Transitions

    DTIC Science & Technology

    2006-06-09

    Podesta for the Heads of Executive Departments and Agencies, “Presidential Transition Guidance,” Nov. 13, 2000. 89 U.S. General Services Administration...2000, presidential election, White House Chief of Staff John Podesta issued a November 13, 2000, memorandum to executive branch agencies stating that

  2. Tessellations & Transitions.

    ERIC Educational Resources Information Center

    Cassidy, Joan

    1998-01-01

    Describes two sixth-grade lessons on the work of M. C. Escher: (1) the first lesson instructs students on tessellations, or tiles that interlock in a repeated pattern; (2) the second lesson explores Escher's drawings of transitions from two- to three-dimensional space. (DSK)

  3. Global health and cardiovascular disease.

    PubMed

    Nascimento, Bruno R; Brant, Luisa C C; Moraes, Diego N; Ribeiro, Antonio L P

    2014-11-01

    The modern definition of Global Health has expanded its scope beyond neglected diseases and low-income and underdeveloped countries. The current initiatives focus on improvement of health, reduction of disparities and protection against global threats, seeking for interaction with health practices, policies and systems. There has been a growing interest on Global Health research, given the epidemiological transition currently underway in low and mid-income countries and the increasing epidemiological importance of cardiovascular and other non-communicable diseases, to the detriment of infectious diseases and nutritional deficiencies. Various aspects-formerly neglected-of these diseases, such as epidemiology, prevention, diagnosis and therapy, have been addressed in Global Health publications, leading to a better understanding of the importance of health as a public good, beyond borders. Scientific evidence supports broader initiatives in which governments, foundations and the civil society must share responsibilities and funding to achieve health equity, the main goal of Global Health.

  4. Eliminating Transitions

    ERIC Educational Resources Information Center

    Gallick, Barb; Lee, Lisa

    2010-01-01

    Adults often find themselves transitioning from one activity to another in a short time span. Most of the time, they do not feel they have a lot of control over their schedules, but wish that they could carve out extended time to relax and focus on one project. Picture a group of children in the block area who have spent 15 or 20 minutes building…

  5. Structural transitions in clusters.

    PubMed

    Hartke, Bernd

    2002-05-03

    If one adds more particles to a cluster, the energetically optimal structure is neither preserved nor does it change in a continuous fashion. Instead, one finds several cluster size regions where one structural principle dominates almost without exception, and rather narrow boundary regions in-between. The structure of the solid is usually reached only at relatively large sizes, after more than one structural transition. The occurrence of this general phenomenon of size-dependent structural transitions does not seem to depend on the nature of the particles, it is found for atomic, molecular, homogeneous, and heterogeneous clusters alike. Clearly, it is a collective many-body phenomenon which can in principle be calculated but not understood in a fully reductionistic manner. Actual calculations with sufficient accuracy are not feasible today, because of the enormous computational expense, even when unconventional evolutionary algorithms are employed for global geometry optimization. Therefore, simple rules for cluster structures are highly desirable. In fact, we are dealing here not just with the academic quest for linkages between cluster structure and features of the potential energy surface, but structural transitions in clusters are also of immediate relevance for many natural and industrial processes, ranging from crystal growth all the way to nanotechnology. This article provides an exemplary overview of research on this topic, from simple model systems where first qualitative explanations start to be successful, up to more realistic complex systems which are still beyond our understanding.

  6. Global and local superconductivity in boron-doped granular diamond.

    PubMed

    Zhang, Gufei; Turner, Stuart; Ekimov, Evgeny A; Vanacken, Johan; Timmermans, Matias; Samuely, Tomás; Sidorov, Vladimir A; Stishov, Sergei M; Lu, Yinggang; Deloof, Bart; Goderis, Bart; Van Tendeloo, Gustaaf; Van de Vondel, Joris; Moshchalkov, Victor V

    2014-04-02

    Strong granularity-correlated and intragrain modulations of the superconducting order parameter are demonstrated in heavily boron-doped diamond situated not yet in the vicinity of the metal-insulator transition. These modulations at the superconducting state (SC) and at the global normal state (NS) above the resistive superconducting transition, reveal that local Cooper pairing sets in prior to the global phase coherence.

  7. Global Programs

    NASA Astrophysics Data System (ADS)

    Lindberg Christensen, Lars; Russo, P.

    2009-05-01

    IYA2009 is a global collaboration between almost 140 nations and more than 50 international organisations sharing the same vision. Besides the common brand, mission, vision and goals, IAU established eleven cornerstones programmes to support the different IYA2009 stakeholder to organize events, activities under a common umbrella. These are global activities centred on specific themes and are aligned with IYA2009's main goals. Whether it is the support and promotion of women in astronomy, the preservation of dark-sky sites around the world or educating and explaining the workings of the Universe to millions, the eleven Cornerstones are key elements in the success of IYA2009. However, the process of implementing global projects across cultural boundaries is challenging and needs central coordination to preserve the pre-established goals. During this talk we will examine the ups and downs of coordinating such a project and present an overview of the principal achievements for the Cornerstones so far.

  8. Global Health

    MedlinePlus

    ... 30, 2017 More news Who We Are Our Strategy Our Jobs Our Funding Our Leadership Global Health Our Newsletter Where We Work Download Fact Sheets Overseas Rightsizing What CDC Is Doing Who We Are Our Strategy Our Funding Our Partnerships Our Organization Our Leadership ...

  9. Global Warming.

    ERIC Educational Resources Information Center

    Hileman, Bette

    1989-01-01

    States the foundations of the theory of global warming. Describes methodologies used to measure the changes in the atmosphere. Discusses steps currently being taken in the United States and the world to slow the warming trend. Recognizes many sources for the warming and the possible effects on the earth. (MVL)

  10. Global Warming?

    ERIC Educational Resources Information Center

    Eichman, Julia Christensen; Brown, Jeff A.

    1994-01-01

    Presents information and data on an experiment designed to test whether different atmosphere compositions are affected by light and temperature during both cooling and heating. Although flawed, the experiment should help students appreciate the difficulties that researchers face when trying to find evidence of global warming. (PR)

  11. Global Change

    USGS Publications Warehouse

    ,

    1993-01-01

    Global change is a relatively new area of scientific study using research from many disciplines to determine how Earth systems change, and to assess the influence of human activity on these changes. This teaching packet consists of a poster and three activity sheets. In teaching these activities four themes are important: time, change, cycles, and Earth as home.

  12. Relation Between Higher Physical Activity and Public Transit Use

    PubMed Central

    Vernez Moudon, Anne; Kang, Bumjoon; Hurvitz, Philip M.; Zhou, Chuan

    2014-01-01

    Objectives. We isolated physical activity attributable to transit use to examine issues of substitution between types of physical activity and potential confounding of transit-related walking with other walking. Methods. Physical activity and transit use data were collected in 2008 to 2009 from 693 Travel Assessment and Community study participants from King County, Washington, equipped with an accelerometer, a portable Global Positioning System, and a 7-day travel log. Physical activity was classified into transit- and non–transit-related walking and nonwalking time. Analyses compared physical activity by type between transit users and nonusers, between less and more frequent transit users, and between transit and nontransit days for transit users. Results. Transit users had more daily overall physical activity and more total walking than did nontransit users but did not differ on either non–transit-related walking or nonwalking physical activity. Most frequent transit users had more walking time than least frequent transit users. Higher physical activity levels for transit users were observed only on transit days, with 14.6 minutes (12.4 minutes when adjusted for demographics) of daily physical activity directly linked with transit use. Conclusions. Because transit use was directly related to higher physical activity, future research should examine whether substantive increases in transit access and use lead to more physical activity and related health improvements. PMID:24625142

  13. Panwapa: Global Kids, Global Connections

    ERIC Educational Resources Information Center

    Berson, Ilene R.; Berson, Michael J.

    2009-01-01

    Panwapa, created by the Sesame Street Workshop of PBS, is an example of an initiative on the Internet designed to enhance students' learning by exposing them to global communities. Panwapa means "Here on Earth" in Tshiluba, a Bantu language spoken in the Democratic Republic of Congo. At the Panwapa website, www.panwapa.org, children aged…

  14. Global health diplomacy and peace.

    PubMed

    Kickbusch, Ilona; Buss, Paulo

    2011-09-01

    Diplomacy and health are in a period of rapid transition, so this article elaborates on the complex multilevel, multiactor negotiation processes that shape and manage the global policy environment for health. It explores the dynamic relationship between health and foreign policy and provides examples from the national, regional, and global levels. Reflecting on the deliberations in different international bodies, it discusses key questions and opportunities that could contribute to moving forward both health and peace agendas. The concluding remarks draw attention to the importance of bridging the capacity gap.

  15. Going Global

    ERIC Educational Resources Information Center

    Boulard, Garry

    2010-01-01

    In a move to increase its out-of-state and international student enrollment, officials at the University of Iowa are stepping up their global recruitment efforts--even in the face of criticism that the school may be losing sight of its mission. The goal is to increase enrollment across the board, with both in-state as well as out-of-state and…

  16. ONR Global

    DTIC Science & Technology

    2012-10-01

    ONRG provides seed funding for innovative research CSP Liaison Visit VSP NICOP Proposal NICOP ADs Making a Difference Graphene • A...better than silicon. ONR Global partnered with UK’s Dr Geim, who was awarded the 2010 Nobel Prize in Physics for his research on graphene . Reducing...total life-cycle costs • Pitch-Adapting Propeller - a propeller blade tip redesign deform as it rotates provides improved efficiency, lower

  17. Global topological k-defects

    SciTech Connect

    Babichev, E.

    2006-10-15

    We consider global topological defects in symmetry-breaking models with a noncanonical kinetic term. Apart from a mass parameter entering the potential, one additional dimensional parameter arises in such models - a kinetic mass. The properties of defects in these models are quite different from standard global domain walls, vortices, and monopoles, if their kinetic mass scale is smaller than their symmetry-breaking scale. In particular, depending on the concrete form of the kinetic term, the typical size of such a defect can be either much larger or much smaller than the size of a standard defect with the same potential term. The characteristic mass of a nonstandard defect, which might have been formed during a phase transition in the early universe, depends on both the temperature of a phase transition and the kinetic mass.

  18. Global Arrays

    SciTech Connect

    Krishnamoorthy, Sriram; Daily, Jeffrey A.; Vishnu, Abhinav; Palmer, Bruce J.

    2015-11-01

    Global Arrays (GA) is a distributed-memory programming model that allows for shared-memory-style programming combined with one-sided communication, to create a set of tools that combine high performance with ease-of-use. GA exposes a relatively straightforward programming abstraction, while supporting fully-distributed data structures, locality of reference, and high-performance communication. GA was originally formulated in the early 1990’s to provide a communication layer for the Northwest Chemistry (NWChem) suite of chemistry modeling codes that was being developed concurrently.

  19. The epithelial-mesenchymal transition induced by keratinocyte growth conditions is overcome by E6 and E7 from HPV16, but not HPV8 and HPV38: Characterization of global transcription profiles

    SciTech Connect

    Azzimonti, Barbara; Dell'Oste, Valentina; Borgogna, Cinzia; Mondini, Michele; Gugliesi, Francesca; De Andrea, Marco; Chiorino, Giovanna; Scatolini, Maria; Ghimenti, Chiara; Landolfo, Santo; Gariglio, Marisa

    2009-06-05

    The aim of this study was to evaluate the growth properties of primary human keratinocytes expressing E6 and E7 proteins, which are from either the beta- or alpha-genotypes, under different culture conditions. We demonstrated that keratinocytes expressing E6 and E7, from both HPV8 and 38, irreversibly underwent the epithelial-mesenchymal transition (EMT) when grown on plastic with FAD medium (F12/DMEM/5%FBS). Expression of E6/E7 from HPV16 was capable of fully overcoming the FAD-induced EMT. Immortalization was only observed in HPV16-transduced cell lines, while the more proliferating phenotype of both KerHPV8 and 38 was mainly related to FAD-induced EMT. Microarray analysis of exponentially growing cells identified 146 cellular genes that were differentially regulated in HPV16 compared to HPV8- and 38-transduced cells. A large accumulation of transcripts associated with epidermal development and differentiation was observed in HPV16-transduced cells, whereas transcripts of genes involved in the extracellular matrix, multicellular organismal processes, and inflammatory response were affected in HPV8 and 38-transduced cells.

  20. Global teaching of global seismology

    NASA Astrophysics Data System (ADS)

    Stein, S.; Wysession, M.

    2005-12-01

    Our recent textbook, Introduction to Seismology, Earthquakes, & Earth Structure (Blackwell, 2003) is used in many countries. Part of the reason for this may be our deliberate attempt to write the book for an international audience. This effort appears in several ways. We stress seismology's long tradition of global data interchange. Our brief discussions of the science's history illustrate the contributions of scientists around the world. Perhaps most importantly, our discussions of earthquakes, tectonics, and seismic hazards take a global view. Many examples are from North America, whereas others are from other areas. Our view is that non-North American students should be exposed to North American examples that are type examples, and that North American students should be similarly exposed to examples elsewhere. For example, we illustrate how the Euler vector geometry changes a plate boundary from spreading, to strike-slip, to convergence using both the Pacific-North America boundary from the Gulf of California to Alaska and the Eurasia-Africa boundary from the Azores to the Mediterranean. We illustrate diffuse plate boundary zones using western North America, the Andes, the Himalayas, the Mediterranean, and the East Africa Rift. The subduction zone discussions examine Japan, Tonga, and Chile. We discuss significant earthquakes both in the U.S. and elsewhere, and explore hazard mitigation issues in different contexts. Both comments from foreign colleagues and our experience lecturing overseas indicate that this approach works well. Beyond the specifics of our text, we believe that such a global approach is facilitated by the international traditions of the earth sciences and the world youth culture that gives students worldwide common culture. For example, a video of the scene in New Madrid, Missouri that arose from a nonsensical earthquake prediction in 1990 elicits similar responses from American and European students.

  1. Topological Lifshitz transitions

    NASA Astrophysics Data System (ADS)

    Volovik, G. E.

    2017-01-01

    Different types of Lifshitz transitions are governed by topology in momentum space. They involve the topological transitions with the change of topology of Fermi surfaces, Weyl and Dirac points, nodal lines, and also the transitions between the fully gapped states.

  2. Transitions: A Personal Perspective.

    ERIC Educational Resources Information Center

    Wood, Ann Stace

    1995-01-01

    Distinguishes between unchosen transitions (children maturing and leaving, parents aging, companies downsizing) and chosen ones (moving, divorce, marriage, career changes). Describes the steps one goes through: uneasiness, renewed energy, complaining, exploration, partial transition, and the completed transition. (JOW)

  3. Global Geomorphology

    NASA Technical Reports Server (NTRS)

    Douglas, I.

    1985-01-01

    Any global view of landforms must include an evaluation of the link between plate tectonics and geomorphology. To explain the broad features of the continents and ocean floors, a basic distinction between the tectogene and cratogene part of the Earth's surface must be made. The tectogene areas are those that are dominated by crustal movements, earthquakes and volcanicity at the present time and are essentially those of the great mountain belts and mid ocean ridges. Cratogene areas comprise the plate interiors, especially the old lands of Gondwanaland and Laurasia. Fundamental as this division between plate margin areas and plate interiors is, it cannot be said to be a simple case of a distinction between tectonically active and stable areas. Indeed, in terms of megageomorphology, former plate margins and tectonic activity up to 600 million years ago have to be considered.

  4. Global warming

    NASA Astrophysics Data System (ADS)

    Houghton, John

    2005-06-01

    'Global warming' is a phrase that refers to the effect on the climate of human activities, in particular the burning of fossil fuels (coal, oil and gas) and large-scale deforestation, which cause emissions to the atmosphere of large amounts of 'greenhouse gases', of which the most important is carbon dioxide. Such gases absorb infrared radiation emitted by the Earth's surface and act as blankets over the surface keeping it warmer than it would otherwise be. Associated with this warming are changes of climate. The basic science of the 'greenhouse effect' that leads to the warming is well understood. More detailed understanding relies on numerical models of the climate that integrate the basic dynamical and physical equations describing the complete climate system. Many of the likely characteristics of the resulting changes in climate (such as more frequent heat waves, increases in rainfall, increase in frequency and intensity of many extreme climate events) can be identified. Substantial uncertainties remain in knowledge of some of the feedbacks within the climate system (that affect the overall magnitude of change) and in much of the detail of likely regional change. Because of its negative impacts on human communities (including for instance substantial sea-level rise) and on ecosystems, global warming is the most important environmental problem the world faces. Adaptation to the inevitable impacts and mitigation to reduce their magnitude are both necessary. International action is being taken by the world's scientific and political communities. Because of the need for urgent action, the greatest challenge is to move rapidly to much increased energy efficiency and to non-fossil-fuel energy sources.

  5. Global gamesmanship.

    PubMed

    MacMillan, Ian C; van Putten, Alexander B; McGrath, Rita Gunther

    2003-05-01

    Competition among multinationals these days is likely to be a three-dimensional game of global chess: The moves an organization makes in one market are designed to achieve goals in another in ways that aren't immediately apparent to its rivals. The authors--all management professors-call this approach "competing under strategic interdependence," or CSI. And where this interdependence exists, the complexity of the situation can quickly overwhelm ordinary analysis. Indeed, most business strategists are terrible at anticipating the consequences of interdependent choices, and they're even worse at using interdependency to their advantage. In this article, the authors offer a process for mapping the competitive landscape and anticipating how your company's moves in one market can influence its competitive interactions in others. They outline the six types of CSI campaigns--onslaughts, contests, guerrilla campaigns, feints, gambits, and harvesting--available to any multiproduct or multimarket corporation that wants to compete skillfully. They cite real-world examples such as the U.S. pricing battle Philip Morris waged with R.J. Reynolds--not to gain market share in the domestic cigarette market but to divert R.J. Reynolds's resources and attention from the opportunities Philip Morris was pursuing in Eastern Europe. And, using data they collected from their studies of consumer-products companies Procter & Gamble and Unilever, the authors describe how to create CSI tables and bubble charts that present a graphical look at the competitive landscape and that may uncover previously hidden opportunities. The CSI mapping process isn't just for global corporations, the authors explain. Smaller organizations that compete with a portfolio of products in just one national or regional market may find it just as useful for planning their next business moves.

  6. Long-term trends and a sustainability transition

    PubMed Central

    Kates, Robert W.; Parris, Thomas M.

    2003-01-01

    How do long-term global trends affect a transition to sustainability? We emphasize the “multitrend” nature of 10 classes of trends, which makes them complex, contradictory, and often poorly understood. Each class includes trends that make a sustainability transition more feasible as well as trends that make it more difficult. Taken in their entirety, they serve as a checklist for the consideration of global trends that impact place-based sustainability studies. PMID:12829798

  7. Long-term trends and a sustainability transition.

    PubMed

    Kates, Robert W; Parris, Thomas M

    2003-07-08

    How do long-term global trends affect a transition to sustainability? We emphasize the "multitrend" nature of 10 classes of trends, which makes them complex, contradictory, and often poorly understood. Each class includes trends that make a sustainability transition more feasible as well as trends that make it more difficult. Taken in their entirety, they serve as a checklist for the consideration of global trends that impact place-based sustainability studies.

  8. Global trends

    NASA Technical Reports Server (NTRS)

    Megie, G.; Chanin, M.-L.; Ehhalt, D.; Fraser, P.; Frederick, J. F.; Gille, J. C.; Mccormick, M. P.; Schoebert, M.; Bishop, L.; Bojkov, R. D.

    1990-01-01

    Measuring trends in ozone, and most other geophysical variables, requires that a small systematic change with time be determined from signals that have large periodic and aperiodic variations. Their time scales range from the day-to-day changes due to atmospheric motions through seasonal and annual variations to 11 year cycles resulting from changes in the sun UV output. Because of the magnitude of all of these variations is not well known and highly variable, it is necessary to measure over more than one period of the variations to remove their effects. This means that at least 2 or more times the 11 year sunspot cycle. Thus, the first requirement is for a long term data record. The second related requirement is that the record be consistent. A third requirement is for reasonable global sampling, to ensure that the effects are representative of the entire Earth. The various observational methods relevant to trend detection are reviewed to characterize their quality and time and space coverage. Available data are then examined for long term trends or recent changes in ozone total content and vertical distribution, as well as related parameters such as stratospheric temperature, source gases and aerosols.

  9. The Transition to a Highly Qualified Workforce

    ERIC Educational Resources Information Center

    Bosworth, Derek; Jones, Paul; Wilson, Rob

    2008-01-01

    Globalization is putting increasing pressure on jobs in the United Kingdom, particularly among less skilled activities. The European response through the Lisbon Strategy has been diffuse, while UK policy appears much more focused, concentrating on the need to raise education and skill levels. The present paper examines the transition towards a…

  10. Guidelines for Transitional Education Plan Preparation

    ERIC Educational Resources Information Center

    Lattanzio, Raphaëlle Martinez; Bethke, Lynne; Haas, Anna; Perrier, Janne Kjaersgaard; De Grauwe, Anton; Sigsgaard, Morten; Bird, Lyndsay; Coury, Diane; Gay, Dorian; MacEwan, Leonora; Seeger, Anna

    2016-01-01

    The "Guidelines for the Transitional Education Plan Preparation" are the result of an extensive consultation process and the product of fruitful guidance and contributions from key partners active in the field of education in emergencies and protracted crises. The new global education agenda 2030 places strong emphasis on countries…

  11. Tips for Transition

    ERIC Educational Resources Information Center

    Kellems, Ryan, Comp.; Morningstar, Mary E., Comp.

    2009-01-01

    The Tips for Transition contains 134 Transition Tips submitted from all over the country by practitioners. The purpose of the Tips was to identify grassroots transition practices being used by practitioners. Tips are categorized into the following domains: (1) Transition Planning; (2) Student Involvement; (3) Family Involvement; (4) Curriculum and…

  12. Ligand induced galectin-3 protein self-association.

    PubMed

    Lepur, Adriana; Salomonsson, Emma; Nilsson, Ulf J; Leffler, Hakon

    2012-06-22

    Many functions of galectin-3 entail binding of its carbohydrate recognition site to glycans of a glycoprotein, resulting in cross-linking thought to be mediated by its N-terminal noncarbohydrate-binding domain. Here we studied interaction of galectin-3 with the model glycoprotein asialofetuin (ASF), using a fluorescence anisotropy assay to measure the concentration of free galectin carbohydrate recognition sites in solution. Surprisingly, in the presence of ASF, this remained low even at high galectin-3 concentrations, showing that many more galectin-3 molecules were engaged than expected due to the about nine known glycan-based binding sites per ASF molecule. This suggests that after ASF-induced nucleation, galectin-3 associates with itself by the carbohydrate recognition site binding to another galectin-3 molecule, possibly forming oligomers. We named this type-C self-association to distinguish it from the previously proposed models (type-N) where galectin-3 molecules bind to each other through the N-terminal domain, and all carbohydrate recognition sites are available for binding glycans. Both types of self-association can result in precipitates, as measured here by turbidimetry and dynamic light scattering. Type-C self-association and precipitation occurred even with a galectin-3 mutant (R186S) that bound poorly to ASF but required much higher concentration (∼50 μM) as compared with wild type (∼1 μM). ASF also induced weaker type-C self-association of galectin-3 lacking its N-terminal domains, but as expected, no precipitation. Neither a monovalent nor a divalent N-acetyl-D-lactosamine-containing glycan induced type-C self-association, even if the latter gave precipitates with high concentrations of galectin-3 (>∼50 μM) in agreement with published results and perhaps due to type-N self-association.

  13. FES kinase participates in KIT-ligand induced chemotaxis

    SciTech Connect

    Voisset, Edwige; Lopez, Sophie; Chaix, Amandine; Vita, Marina; George, Coralie; Dubreuil, Patrice; De Sepulveda, Paulo

    2010-02-26

    FES is a cytoplasmic tyrosine kinase activated by several membrane receptors, originally identified as a viral oncogene product. We have recently identified FES as a crucial effector of oncogenic KIT mutant receptor. However, FES implication in wild-type KIT receptor function was not addressed. We report here that FES interacts with KIT and is phosphorylated following activation by its ligand SCF. Unlike in the context of oncogenic KIT mutant, FES is not involved in wild-type KIT proliferation signal, or in cell adhesion. Instead, FES is required for SCF-induced chemotaxis. In conclusion, FES kinase is a mediator of wild-type KIT signalling implicated in cell migration.

  14. Characterization of Ligand-Induced Endocytosis of EGF-Receptors

    DTIC Science & Technology

    1997-12-01

    Dili domain of Epsl5. They showed that a GST-protein containing the entire COOH-terminal domain of Epsl5 could efficiently precipitate AP- 2 complexes...from cytosol. A construct lacking amino acids 661-739, GST-DfflAl, could also precipitate AP- 2 complexes albiet less efficiently . In contrast...purified AP- 2 complexes restored highly efficient endocytosis. Furhter confirmation of this hypothesis was obtained in another set of experiments

  15. Constitutive and ligand-induced nuclear localization of oxytocin receptor.

    PubMed

    Kinsey, Conan G; Bussolati, Gianni; Bosco, Martino; Kimura, Tadashi; Pizzorno, Marie C; Chernin, Mitchell I; Cassoni, Paola; Novak, Josef F

    2007-01-01

    Oxytocin receptor (OTR) is a membrane protein known to mediate oxytocin (OT) effects, in both normal and neoplastic cells. We report here that human osteosarcoma (U2OS, MG63, OS15 and SaOS2), breast cancer (MCF7), and primary human fibroblastic cells (HFF) all exhibit OTR not only on the cell membrane, but also in the various nuclear compartments including the nucleolus. Both an OTR-GFP fusion protein and the native OTR appear to be localized to the nucleus as detected by transfection and/or confocal immunofluorescence, respectively. Treatment with oxytocin causes internalization of OTR and the resulting vesicles accumulate in the vicinity of the nucleus and some of the perinuclear OTR enters the nucleus. Western blots indicate that OTR in the nucleus and on the plasma membrane are likely to be the same biochemical and immunological entities. It appears that OTR is first visible in the nucleoli and subsequently disperses within the nucleus into 4-20 spots while some of the OTR diffuses throughout the nucleoplasm. The behaviour and kinetics of OTR-GFP and OTR are different, indicating interference by GFP in both OTR entrance into the nucleus and subsequent relocalization of OTR within the nucleus. There are important differences among the tested cells, such as the requirement of a ligand for transfer of OTR in nuclei. A constitutive internalization of OTR was found only in osteosarcoma cells, while the nuclear localization in all other tested cells was dependent on ligand binding. The amount of OTR-positive material within and in the vicinity of the nucleus increased following a treatment with oxytocin in both constitutive and ligand-dependent type of cells. The evidence of OTR compartmentalization at the cell nucleus (either ligand-dependent or constitutive) in different cell types suggests still unknown biological functions of this protein or its ligand and adds this G-protein-coupled receptor to other heptahelical receptors displaying this atypical and unexpected nuclear localization.

  16. Ligand-induced ErbB receptor dimerization

    PubMed Central

    Lemmon, Mark A.

    2009-01-01

    Structural studies have provided important new insights into how ligand binding promotes homodimerization and activation of the EGF receptor and the other members of the ErbB family or receptor tyrosine kinases. These structures have also suggested possible explanations for the unique properties of ErbB2, which has no known ligand and can cause cell transformation (and tumorigenesis) by simple overexpression. In parallel with these advances, studies of the EGF receptor at the cell surface increasingly argue that the structural studies are missing key mechanistic components. This is particularly evident in the structural prediction that EGF binding linked to receptor dimerization should be positively cooperative, whereas cell-surface EGF-binding studies suggest negative cooperativity. In this review, I summarize studies of ErbB receptor extracellular regions in solution and of intact receptors at the cell surface, and attempt to reconcile the differences suggested by the two approaches. By combining results obtained with receptor ‘parts’, it is qualitatively possible to explain some models for the properties of the whole receptor. These considerations underline the need to consider the intact ErbB receptors as intact allosterically regulated enzymes, and to combine cellular and structural studies into a complete picture. PMID:19038249

  17. Methods for creating ligand induced paramagnetism in nanocrystalline structures

    DOEpatents

    Meulenberg, Robert W.; Lee, Jonathan R. I.; Van Buuren, Anthony W.; Terminello, Louis J.

    2016-12-13

    A method according to one general embodiment includes applying an organic surfactant to a nanoparticle having a d.sup.10 configuration for altering a magnetic property of the nanoparticle. A method according to another general embodiment includes applying an organic surfactant to a II-VI semiconductor nanoparticle having a d.sup.10 configuration for altering a magnetic property of the nanoparticle, wherein the nanoparticle has a mean radius of less than about 50 .ANG..

  18. Mode Transitions in Hall Effect Thrusters

    NASA Technical Reports Server (NTRS)

    Sekerak, Michael J.; Longmier, Benjamin W.; Gallimore, Alec D.; Brown, Daniel L.; Hofer, Richard R.; Polk, James E.

    2013-01-01

    Mode transitions have been commonly observed in Hall Effect Thruster (HET) operation where a small change in a thruster operating parameter such as discharge voltage, magnetic field or mass flow rate causes the thruster discharge current mean value and oscillation amplitude to increase significantly. Mode transitions in a 6-kW-class HET called the H6 are induced by varying the magnetic field intensity while holding all other operating parameters constant and measurements are acquired with ion saturation probes and ultra-fast imaging. Global and local oscillation modes are identified. In the global mode, the entire discharge channel oscillates in unison and azimuthal perturbations (spokes) are either absent or negligible. Downstream azimuthally spaced probes show no signal delay between each other and are very well correlated to the discharge current signal. In the local mode, signals from the azimuthally spaced probes exhibit a clear delay indicating the passage of "spokes" and are not well correlated to the discharge current. These spokes are localized oscillations propagating in the ExB direction that are typically 10-20% of the mean value. In contrast, the oscillations in the global mode can be 100% of the mean value. The transition between global and local modes occurs at higher relative magnetic field strengths for higher mass flow rates or higher discharge voltages. The thrust is constant through mode transition but the thrust-to-power decreased by 25% due to increasing discharge current. The plume shows significant differences between modes with the global mode significantly brighter in the channel and the near-field plasma plume as well as exhibiting a luminous spike on thruster centerline. Mode transitions provide valuable insight to thruster operation and suggest improved methods for thruster performance characterization.

  19. The Psychological Impacts of Global Climate Change

    ERIC Educational Resources Information Center

    Doherty, Thomas J.; Clayton, Susan

    2011-01-01

    An appreciation of the psychological impacts of global climate change entails recognizing the complexity and multiple meanings associated with climate change; situating impacts within other social, technological, and ecological transitions; and recognizing mediators and moderators of impacts. This article describes three classes of psychological…

  20. Global Knowledge: A Challenge for Librarians.

    ERIC Educational Resources Information Center

    Edwards, Christopher

    This paper describes how Information and Communication Technologies (ICT) are creating the knowledge society, which will impact on developing and transitional economies as well as developed nations. It argues that librarians have an important role to play in overcoming the digital divide and makes reference to the Global Knowledge Partnership.…

  1. Gas turbine combustor transition

    DOEpatents

    Coslow, Billy Joe; Whidden, Graydon Lane

    1999-01-01

    A method of converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit.

  2. Gas turbine combustor transition

    DOEpatents

    Coslow, B.J.; Whidden, G.L.

    1999-05-25

    A method is described for converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit. 7 figs.

  3. Global F-theory GUTs

    SciTech Connect

    Blumenhagen, Ralph; Grimm, Thomas W.; Jurke, Benjamin; Weigand, Timo; /SLAC

    2010-08-26

    We construct global F-theory GUT models on del Pezzo surfaces in compact Calabi-Yau fourfolds realized as complete intersections of two hypersurface constraints. The intersections of the GUT brane and the flavour branes as well as the gauge flux are described by the spectral cover construction. We consider a split S[U(4) x U(1){sub X}] spectral cover, which allows for the phenomenologically relevant Yukawa couplings and GUT breaking to the MSSM via hypercharge flux while preventing dimension-4 proton decay. General expressions for the massless spectrum, consistency conditions and a new method for the computation of curvature-induced tadpoles are presented. We also provide a geometric toolkit for further model searches in the framework of toric geometry. Finally, an explicit global model with three chiral generations and all required Yukawa couplings is defined on a Calabi-Yau fourfold which is fibered over the del Pezzo transition of the Fano threefold P{sup 4}.

  4. Conceptualizing Transitions to Adulthood

    ERIC Educational Resources Information Center

    Wyn, Johanna

    2014-01-01

    This chapter provides an overview of theories of the transition to young adulthood. It sets out the argument for conceptual renewal and discusses some implications of new patterns of transition for adult education.

  5. Transition to Adulthood

    MedlinePlus

    ... fix that! Keep reading… Back to top IDEA’s Definition of Transition Services Any discussion of transition services ... from special education. Back to top Considering the Definition A number of key words in the definition ...

  6. Transition in Turbines

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The concept of a large disturbance bypass mechanism for the initiation of transition is reviewed and studied. This mechanism, or some manifestation thereof, is suspected to be at work in the boundary layers present in a turbine flow passage. Discussion is presented on four relevant subtopics: (1) the effect of upstream disturbances and wakes on transition; (2) transition prediction models, code development, and verification; (3) transition and turbulence measurement techniques; and (4) the hydrodynamic condition of low Reynolds number boundary layers.

  7. Cosmological phase transitions

    SciTech Connect

    Kolb, E.W. |

    1993-10-01

    If modern ideas about the role of spontaneous symmetry breaking in fundamental physics are correct, then the Universe should have undergone a series of phase transitions early in its history. The study of cosmological phase transitions has become an important aspect of early-Universe cosmology. In this lecture I review some very recent work on three aspects of phase transitions: the electroweak transition, texture, and axions.

  8. Financing pharmaceuticals in transition economies.

    PubMed

    Kanavos, P

    1999-06-01

    This paper (a) provides a methodological taxonomy of pricing, financing, reimbursement, and cost containment methodologies for pharmaceuticals; (b) analyzes complex agency relationships and the health versus industrial policy tradeoff; (c) pinpoints financing measures to balance safety and effectiveness of medicines and their affordability by publicly funded systems in transition; and (d) highlights viable options for policy-makers for the financing of pharmaceuticals in transition. Three categories of measures and their implications for pharmaceutical policy cost containing are analyzed: supply-side measures, targeting manufacturers, proxy demand-side measures, targeting physicians and pharmacists, and demand-side measures, targeting patients. In pursuing supply side measures, we explore free pricing for pharmaceuticals, direct price controls, cost-plus and cost pricing, average pricing and international price comparisons, profit control, reference pricing, the introduction of a fourth hurdle, positive and negative lists, and other price control measures. The analysis of proxy-demand measures includes budgets for physicians, generic policies, practice guidelines, monitoring the authorizing behavior of physicians, and disease management schemes. Demand-side measures explore the effectiveness of patient co-payments, the impact of allowing products over-the-counter and health promotion programs. Global policies should operate simultaneously on the supply, the proxy demand, and the demand-side. Policy-making needs to have a continuous long-term planning. The importation of policies into transition economy may require extensive and expensive adaptation, and/or lead to sub-optimal policy outcomes.

  9. Trust Transitivity in Social Networks

    PubMed Central

    Richters, Oliver; Peixoto, Tiago P.

    2011-01-01

    Non-centralized recommendation-based decision making is a central feature of several social and technological processes, such as market dynamics, peer-to-peer file-sharing and the web of trust of digital certification. We investigate the properties of trust propagation on networks, based on a simple metric of trust transitivity. We investigate analytically the percolation properties of trust transitivity in random networks with arbitrary in/out-degree distributions, and compare with numerical realizations. We find that the existence of a non-zero fraction of absolute trust (i.e. entirely confident trust) is a requirement for the viability of global trust propagation in large systems: The average pair-wise trust is marked by a discontinuous transition at a specific fraction of absolute trust, below which it vanishes. Furthermore, we perform an extensive analysis of the Pretty Good Privacy (PGP) web of trust, in view of the concepts introduced. We compare different scenarios of trust distribution: community- and authority-centered. We find that these scenarios lead to sharply different patterns of trust propagation, due to the segregation of authority hubs and densely-connected communities. While the authority-centered scenario is more efficient, and leads to higher average trust values, it favours weakly-connected “fringe” nodes, which are directly trusted by authorities. The community-centered scheme, on the other hand, favours nodes with intermediate in/out-degrees, in detriment of the authorities and its “fringe” peers. PMID:21483683

  10. Conformational transitions and interactions underlying the function of membrane embedded receptor protein kinases.

    PubMed

    Bocharov, Eduard V; Sharonov, Georgy V; Bocharova, Olga V; Pavlov, Konstantin V

    2017-01-25

    Among membrane receptors, the single-span receptor protein kinases occupy a broad but specific functional niche determined by distinctive features of the underlying transmembrane signaling mechanisms that are briefly overviewed on the basis of some of the most representative examples, followed by a more detailed discussion of several hierarchical levels of organization and interactions involved. All these levels, including single-molecule interactions (e.g., dimerization, liganding, chemical modifications), local processes (e.g. lipid membrane perturbations, cytoskeletal interactions), and larger scale phenomena (e.g., effects of membrane surface shape or electrochemical potential gradients) appear to be closely integrated to achieve the observed diversity of the receptor functioning. Different species of receptor protein kinases meet their specific functional demands through different structural features defining their responses to stimulation, but certain common patterns exist. Signaling by receptor protein kinases is typically associated with the receptor dimerization and clustering, ligand-induced rearrangements of receptor domains through allosteric conformational transitions with involvement of lipids, release of the sequestered lipids, restriction of receptor diffusion, cytoskeleton and membrane shape remodeling. Understanding of complexity and continuity of the signaling processes can help identifying currently neglected opportunities for influencing the receptor signaling with potential therapeutic implications. This article is part of a Special Issue entitled: Interactions between membrane receptors in cellular membranes edited by Kalina Hristova.

  11. Transition: Preschool to Kindergarten

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    Transition is movement or change without interruption. It should be a smooth flow from one place or condition to another. While the transition plan for a student receiving special education services is designed to prepare him or her for life after high school, transition can start when a child enters preschool. The second of six distinct stages of…

  12. Transition. Feature Issue.

    ERIC Educational Resources Information Center

    Wallace, Teri, Ed.; And Others

    1992-01-01

    This feature issue of a quarterly bulletin on community integration addresses the topic of transition services for preparing youth with disabilities for adult community living. It contains articles with the following titles and authors: "Transition: The Next Five Years" (David R. Johnson and others); "Transition Policy in the 1990s:…

  13. Seoul Searching: Transitioning Basic Writers within the Global Frontiers Project

    ERIC Educational Resources Information Center

    Adkins, Tabetha; Meyer, Connie

    2014-01-01

    The course described here was designed especially for students enrolled in a collaborative program between Texas A&M University-Commerce and Konkuk University in South Korea. This course was created specifically for students who did not earn a qualifying score on a standardized placement exam required of all first-year students for enrollment…

  14. America’s Transitional Capacity: War, Systems, and Globalization

    DTIC Science & Technology

    2013-05-23

    politics. Under the legacy of the shelved Morgenthau Plan, German economy suffered through a five-year period of industrial disarmament.160 This is the...Germany, which outlined a soft approach to restoration.171 The Secretary of Treasury Henry Morgenthau called for a more hard line approach that sought to

  15. Transit pricing and performance

    SciTech Connect

    Pickerell, D.H.; Abkowitz, M.; Tozzi, J.; McCord, M.R.; Cheng, L.H.

    1986-01-01

    The 9 papers in the report deal with the following areas: Federal operating assistance for urban mass transit; a decade of experience; transit route characteristics and headway-based reliability control; day-of-week and part-of-month variation in bus ridership; job satisfaction and transit operator recognition programs; results of a survey of muni operators; bus marketing costs: the experience of 18 section 15 reporters from 1981 to 1983; prospects for differential transit pricing in the United States; an initial analysis of total factor productivity for public-transit coordination of transportation resources: the Georgia experience; absenteeism, accidents, and attrition: part-time versus full-time bus drivers.

  16. Transit of Venus Culture: A Celestial Phenomenon Intrigues the Public

    NASA Astrophysics Data System (ADS)

    Bueter, Chuck

    2012-01-01

    When Jeremiah Horrocks first observed it in 1639, the transit of Venus was a desirable telescopic target because of its scientific value. By the next transit of Venus in 1761, though, the enlightened public also embraced it as a popular celestial phenomenon. Its stature elevated over the centuries, the transit of Venus has been featured in music, poetry, stamps, plays, books, and art. The June 2004 transit emerged as a surprising global sensation, as suggested by the search queries it generated. Google's Zeitgeist deemed Venus Transit to be the #1 Most Popular Event in the world for that month. New priorities, technologies, and media have brought new audiences to the rare alignment. As the 2012 transit of Venus approaches, the trend continues with publicly accessible capabilities that did not exist only eight years prior. For example, sites from which historic observations have been made are plotted and readily available on Google Earth. A transit of Venus phone app in development will, if fully funded, facilitate a global effort to recreate historic expeditions by allowing smartphone users to submit their observed transit timings to a database for quantifying the Astronomical Unit. While maintaining relevance in modern scientific applications, the transit of Venus has emerged as a cultural attraction that briefly intrigues the mainstream public and inspires their active participation in the spectacle.

  17. Globalization and human cooperation.

    PubMed

    Buchan, Nancy R; Grimalda, Gianluca; Wilson, Rick; Brewer, Marilynn; Fatas, Enrique; Foddy, Margaret

    2009-03-17

    Globalization magnifies the problems that affect all people and that require large-scale human cooperation, for example, the overharvesting of natural resources and human-induced global warming. However, what does globalization imply for the cooperation needed to address such global social dilemmas? Two competing hypotheses are offered. One hypothesis is that globalization prompts reactionary movements that reinforce parochial distinctions among people. Large-scale cooperation then focuses on favoring one's own ethnic, racial, or language group. The alternative hypothesis suggests that globalization strengthens cosmopolitan attitudes by weakening the relevance of ethnicity, locality, or nationhood as sources of identification. In essence, globalization, the increasing interconnectedness of people worldwide, broadens the group boundaries within which individuals perceive they belong. We test these hypotheses by measuring globalization at both the country and individual levels and analyzing the relationship between globalization and individual cooperation with distal others in multilevel sequential cooperation experiments in which players can contribute to individual, local, and/or global accounts. Our samples were drawn from the general populations of the United States, Italy, Russia, Argentina, South Africa, and Iran. We find that as country and individual levels of globalization increase, so too does individual cooperation at the global level vis-à-vis the local level. In essence, "globalized" individuals draw broader group boundaries than others, eschewing parochial motivations in favor of cosmopolitan ones. Globalization may thus be fundamental in shaping contemporary large-scale cooperation and may be a positive force toward the provision of global public goods.

  18. Veterans in Transition: Implications for Nurse Educators.

    PubMed

    Dyar, Kelly L

    2016-07-01

    Recently the United States military has begun strategic reductions in force and as a result many veterans are utilizing education benefits to transition from combat to classroom. During this transitional period, veterans entering nursing programs may struggle to transition from the combat experience to the college campus. Barriers to transition can include stigma, difficulty with peer relationships, differences in military and nursing education structure, and personal and financial responsibilities. Regardless of these barriers, this population, which may include highly trained combat medics and corpsmen, may also bring assets gained through military training and experience that can enhance the nursing profession. These strengths include teamwork, perseverance, ability to focus on assignments, global awareness, and increased self-efficacy. Nursing education research is lacking in the area of combat veterans transitioning into nursing programs, prompting the concern that nursing education is not prepared to meet the needs of this unique population. Gaining better understanding of the barriers to transition and strengths gained through combat can aid the nurse educator in better meeting the needs of this unique population of students. Dyar.

  19. Global Awareness and Perspectives in Global Education

    ERIC Educational Resources Information Center

    Burnouf, Laura

    2004-01-01

    This paper examines the whole notion of global education by discussing theoretical and practical understandings by major figures in the field. Global education is a recent addition in social studies and there are many different understandings and conceptual which effectively teach the concepts in schools as part of the entire curriculum. A review…

  20. Transforming Academic Globalization into Globalization for All

    ERIC Educational Resources Information Center

    Ramalhoto, M. F.

    2006-01-01

    Driving innovation and continuous improvement with regard to ecological, environmental and human sustainability is essential for win-win globalization. That calls for research on strategic and monitoring planning to manage globalization and technological and scientific change. This paper describes a new basic function of the university institution…

  1. Globalization and human cooperation

    PubMed Central

    Buchan, Nancy R.; Grimalda, Gianluca; Wilson, Rick; Brewer, Marilynn; Fatas, Enrique; Foddy, Margaret

    2009-01-01

    Globalization magnifies the problems that affect all people and that require large-scale human cooperation, for example, the overharvesting of natural resources and human-induced global warming. However, what does globalization imply for the cooperation needed to address such global social dilemmas? Two competing hypotheses are offered. One hypothesis is that globalization prompts reactionary movements that reinforce parochial distinctions among people. Large-scale cooperation then focuses on favoring one's own ethnic, racial, or language group. The alternative hypothesis suggests that globalization strengthens cosmopolitan attitudes by weakening the relevance of ethnicity, locality, or nationhood as sources of identification. In essence, globalization, the increasing interconnectedness of people worldwide, broadens the group boundaries within which individuals perceive they belong. We test these hypotheses by measuring globalization at both the country and individual levels and analyzing the relationship between globalization and individual cooperation with distal others in multilevel sequential cooperation experiments in which players can contribute to individual, local, and/or global accounts. Our samples were drawn from the general populations of the United States, Italy, Russia, Argentina, South Africa, and Iran. We find that as country and individual levels of globalization increase, so too does individual cooperation at the global level vis-à-vis the local level. In essence, “globalized” individuals draw broader group boundaries than others, eschewing parochial motivations in favor of cosmopolitan ones. Globalization may thus be fundamental in shaping contemporary large-scale cooperation and may be a positive force toward the provision of global public goods. PMID:19255433

  2. Gravitationally induced quantum transitions

    NASA Astrophysics Data System (ADS)

    Landry, A.; Paranjape, M. B.

    2016-06-01

    In this paper, we calculate the probability for resonantly inducing transitions in quantum states due to time-dependent gravitational perturbations. Contrary to common wisdom, the probability of inducing transitions is not infinitesimally small. We consider a system of ultracold neutrons, which are organized according to the energy levels of the Schrödinger equation in the presence of the Earth's gravitational field. Transitions between energy levels are induced by an oscillating driving force of frequency ω . The driving force is created by oscillating a macroscopic mass in the neighborhood of the system of neutrons. The neutron lifetime is approximately 880 sec while the probability of transitions increases as t2. Hence, the optimal strategy is to drive the system for two lifetimes. The transition amplitude then is of the order of 1.06 ×10-5, and hence with a million ultracold neutrons, one should be able to observe transitions.

  3. Transition Region Models

    NASA Astrophysics Data System (ADS)

    Hansteen, V.; Murdin, P.

    2000-11-01

    The SOLAR TRANSITION REGION comprises the PLASMA between the CHROMOSPHERE and the CORONA. In both of these regions the temperature is fairly uniform. The transition region, by contrast, is believed to be characterized by a very steep temperature rise from a chromospheric temperature of slightly less than 104 K to coronal temperatures on the order of 106 K. The goal of modeling the transition regi...

  4. Global quantum discord in multipartite systems

    SciTech Connect

    Rulli, C. C.; Sarandy, M. S.

    2011-10-15

    We propose a global measure for quantum correlations in multipartite systems, which is obtained by suitably recasting the quantum discord in terms of relative entropy and local von Neumann measurements. The measure is symmetric with respect to subsystem exchange and is shown to be nonnegative for an arbitrary state. As an illustration, we consider tripartite correlations in the Werner-GHZ (Greenberger-Horne-Zeilinger) state and multipartite correlations at quantum criticality. In particular, in contrast with the pairwise quantum discord, we show that the global quantum discord is able to characterize the infinite-order quantum phase transition in the Ashkin-Teller spin chain.

  5. Global health diplomacy.

    PubMed

    Adams, Vincanne; Novotny, Thomas E; Leslie, Hannah

    2008-01-01

    A variety of shifts emergent with globalization, which are reflected in part by nascent programs in "Global Public Health," "Global Health Sciences," and "Global Health," are redefining international public health. We explore three of these shifts as a critical discourse and intervention in global health diplomacy: the expansion in non-governmental organization participation in international health programs, the globalization of science and pharmaceutical research, and the use of militarized languages of biosecurity to recast public health programs. Using contemporary anthropological and international health literature, we offer a critical yet hopeful exploration of the implications of these shifts for critical inquiry, health, and the health professions.

  6. Analyzing sustainability transitions as a shift between socio-metabolic regimes

    PubMed Central

    Fischer-Kowalski, Marina

    2011-01-01

    This essay seeks to specify the theoretical choices and assumptions involved in studying sociometabolic transitions, such as sustainability transitions, in a way that distinguishes them from mere “changes”. These generalizations draw on experiences with the empirical analysis of historical transitions on various scale levels. This perspective is illustrated by using material and energy flow data to demonstrate global sociometabolic regime transitions during the 20th century. PMID:27066392

  7. Spin-Polarization-Induced Preedge Transitions in the Sulfur K-Edge XAS Spectra of Open-Shell Transition-Metal Sulfates: Spectroscopic Validation of σ-Bond Electron Transfer.

    PubMed

    Frank, Patrick; Szilagyi, Robert K; Gramlich, Volker; Hsu, Hua-Fen; Hedman, Britt; Hodgson, Keith O

    2017-02-06

    Sulfur K-edge X-ray absorption spectroscopy (XAS) spectra of the monodentate sulfate complexes [M(II)(itao)(SO4)(H2O)0,1] (M = Co, Ni, Cu) and [Cu(Me6tren)(SO4)] exhibit well-defined preedge transitions at 2479.4, 2479.9, 2478.4, and 2477.7 eV, respectively, despite having no direct metal-sulfur bond, while the XAS preedge of [Zn(itao)(SO4)] is featureless. The sulfur K-edge XAS of [Cu(itao)(SO4)] but not of [Cu(Me6tren)(SO4)] uniquely exhibits a weak transition at 2472.1 eV, an extraordinary 8.7 eV below the first inflection of the rising K-edge. Preedge transitions also appear in the sulfur K-edge XAS of crystalline [M(II)(SO4)(H2O)] (M = Fe, Co, Ni, and Cu, but not Zn) and in sulfates of higher-valent early transition metals. Ground-state density functional theory (DFT) and time-dependent DFT (TDDFT) calculations show that charge transfer from coordinated sulfate to paramagnetic late transition metals produces spin polarization that differentially mixes the spin-up (α) and spin-down (β) spin orbitals of the sulfate ligand, inducing negative spin density at the sulfate sulfur. Ground-state DFT calculations show that sulfur 3p character then mixes into metal 4s and 4p valence orbitals and various combinations of ligand antibonding orbitals, producing measurable sulfur XAS transitions. TDDFT calculations confirm the presence of XAS preedge features 0.5-2 eV below the rising sulfur K-edge energy. The 2472.1 eV feature arises when orbitals at lower energy than the frontier occupied orbitals with S 3p character mix with the copper(II) electron hole. Transmission of spin polarization and thus of radical character through several bonds between the sulfur and electron hole provides a new mechanism for the counterintuitive appearance of preedge transitions in the XAS spectra of transition-metal oxoanion ligands in the absence of any direct metal-absorber bond. The 2472.1 eV transition is evidence for further radicalization from copper(II), which extends across a

  8. Urgent need for human resources to promote global cardiovascular health.

    PubMed

    Vedanthan, Rajesh; Fuster, Valentin

    2011-02-01

    The World Health Organization estimates the existence of a global shortage of over 4 million health-care workers. Given the growing global burden of cardiovascular disease (CVD), the shortfall in global human resources for health (HRH) is probably even greater than predicted. A critical challenge going forward is to determine how to integrate CVD-related human resource needs into the overall global HRH agenda. We describe the CVD implications of core HRH objectives, including coverage, motivation, and competence, in addition to issues such as health-care worker migration and the need for input from multiple stakeholders to successfully address the current problems. We emphasize gaps in knowledge regarding HRH for global CVD-related care and research opportunities. In light of the current global epidemiologic transition from communicable to noncommunicable diseases, now is the time for the global health community to focus on CVD-related human resource needs.

  9. Global solidarity, migration and global health inequity.

    PubMed

    Eckenwiler, Lisa; Straehle, Christine; Chung, Ryoa

    2012-09-01

    The grounds for global solidarity have been theorized and conceptualized in recent years, and many have argued that we need a global concept of solidarity. But the question remains: what can motivate efforts of the international community and nation-states? Our focus is the grounding of solidarity with respect to global inequities in health. We explore what considerations could motivate acts of global solidarity in the specific context of health migration, and sketch briefly what form this kind of solidarity could take. First, we argue that the only plausible conceptualization of persons highlights their interdependence. We draw upon a conception of persons as 'ecological subjects' and from there illustrate what such a conception implies with the example of nurses migrating from low and middle-income countries to more affluent ones. Next, we address potential critics who might counter any such understanding of current international politics with a reference to real-politik and the insights of realist international political theory. We argue that national governments--while not always or even often motivated by moral reasons alone--may nevertheless be motivated to acts of global solidarity by prudential arguments. Solidarity then need not be, as many argue, a function of charitable inclination, or emergent from an acknowledgment of injustice suffered, but may in fact serve national and transnational interests. We conclude on a positive note: global solidarity may be conceptualized to helpfully address global health inequity, to the extent that personal and transnational interdependence are enough to motivate national governments into action.

  10. Aerothermodynamics of the Mars Global Surveyor Spacecraft

    NASA Technical Reports Server (NTRS)

    Shane, Russell W.; Tolson, Robert H.

    1998-01-01

    The aerothermodynamics characteristics of the Mars Global Surveyor spacecraft are investigated and reported. These results have been used by the Mars Global Surveyor mission planners to design the aerobraking phase of the mission. Analytical and Direct Simulation Monte Carlo computer codes were used with a detailed, three dimensional model of the spacecraft to evaluate spacecraft aerobraking characteristics for flight in free molecular and transitional flow regimes. The spacecraft is found to be aerodynamically stable in aerobraking and planned contingency configurations. Aerodynamic forces, moments, and heating are found to be highly dependent on atmospheric density. Accommodation coefficient. is seen to strongly influence drag coefficient. Transitional flow effects are found to reduce overall solar panel heating. Attitude control thruster plumes are shown to interact with the freestream, diminishing the effectiveness of the attitude control system and even leading to thrust reversal. These plume-freestream interaction effects are found to be highly dependent on freestream density.

  11. [From epidemiological transition to health transition].

    PubMed

    Meslé, F; Vallin, J

    2007-12-01

    The "Epidemiological Transition" concept proposed by Abdel Omran in 1971 was the first theory attempting to explain the extraordinary progess that industrialized countries have achieved in health since the 18th century. Within the broader framework of the demographic transition, an important implication of this concept was that life expectancy in modern societies would converge toward limits determined by the new epidemiological conditions. In the ensuing decades, however the convergence process appears to have stopped as a result of a number of setbacks including the health crisis in Eastern Europe and AIDS in Africa. These setbacks do not fundamentally contradict the theory. A much greater contradiction was the unexpected dramatic decrease in cardiovascular disease that began as early as the 70s and had a major positive impact on life expectancy. Based on the concept of "Health Transition" described by Julio Frenk et al., we propose a complete revision of the health implications of the demographic transition based the idea of successive cycles of divergences/convergences induced by the appearance and generalization of major breakthroughs in health technologies and strategies. Three such cycles can be clearly identified on an international level corresponding to control of infectious then cardiovascular diseases, and perhaps most recently to the initial successes achieved in the field of ageing.

  12. Transient Global Amnesia

    MedlinePlus

    ... global amnesia is a sudden, temporary episode of memory loss that can't be attributed to a ... know well. But that doesn't make your memory loss less disturbing. Fortunately, transient global amnesia is ...

  13. Global climate change

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.

    1991-01-01

    Present processes of global climate change are reviewed. The processes determining global temperature are briefly described and the concept of effective temperature is elucidated. The greenhouse effect is examined, including the sources and sinks of greenhouse gases.

  14. IMERG Global Precipitation Rates

    NASA Video Gallery

    NASA's Global Precipitation Measurement mission has produced its first global map of rainfall and snowfall. The GPM Core Observatory launched one year ago on Feb. 27, 2014 as a collaboration betwee...

  15. The Global Menace.

    PubMed

    Hodges, Sarah

    2012-08-01

    The history of medicine has gone 'global.' Why? Can the proliferation of the 'global' in our writing be explained away as a product of staying true to our historical subjects' categories? Or has this historiography in fact delivered a new 'global' problematic or performed serious 'global' analytic work? The situation is far from clear, and it is the tension between the global as descriptor and an analytics of the global that concerns me here. I have three main concerns: (1) that there is an epistemic collusion between the discourses of universality that inform medical science and global-talk; (2) that the embrace of the 'global' authorises a turning away from analyses of power in history-writing in that (3) this turning away from analyses of power in history-writing leads to scholarship that reproduces rather than critiques globalisation as a set of institutions, discourses and practices.

  16. Promoting "Global" Attitudes.

    ERIC Educational Resources Information Center

    Case, Roland

    1996-01-01

    Discusses and illustrates three ways to promote prosocial attitudes towards global issues among students. Includes classroom environments that reinforce desired attitudes; facilitating direct "emotional" experiences that influence attitudes; and engaging students in thoughtful deliberation about global issues. Offers illustrative…

  17. Modeling Global Change in Local Places: Capturing Global Change and Local Impacts in a Global Land System Change Model

    NASA Astrophysics Data System (ADS)

    Verburg, P.; Eitelberg, D.; Ornetsmueller, C.; van Vliet, J.

    2015-12-01

    Global land use models are driven by demands for food and urban space. However, at the same time many transitions in land use and land cover are driven by societal changes and the demand for a wide range of landscape functions or ecosystem services, including the conservation of biodiversity, regulation of climate and floods, and recreation. Some of these demands lead to tele-connected land use change through the transport of good and services, others are place-based and shape the local realities of land system change. Most current land use change models focus on land cover changes alone and ignore the importance of changes in land management and landscape configuration that affect climate, biodiversity and the provisioning of ecosystem services. This talk will present an alternative approach to global land use modelling based on the simulation of changes in land systems in response to a wide set of ecosystem service demands. Simulations at global scale illustrate that accounting for demands for livestock products, carbon sequestration and biological conservation (following the Aichi targets) leads to different outcomes of land change models and allows the identification of synergies between carbon and biodiversity targets. An application in Laos indicates the complex transitions in land systems and landscapes that occur upon the transition from shifting cultivation to permanent agriculture and tree-crop plantations. We discuss the implications of such land system representations for Earth system modelling.

  18. Globalization and State Soverignty

    DTIC Science & Technology

    2007-11-02

    Grahame Thompson, Globalization in Question , (Macitutious, Polity Press, 2000, 2nd edition), 256-257. Islam, M. Monwarul., “Globalization and Future of... in Question , (Macitutious, Polity Press, 2000, 2nd edition), 256-257. 8 Martin Wolf, “Will the Nation State Survive Globalization?” Foreign Affairs...Among Many?” Interview with Lebel France- January 2000; available from <http://www.france.diplomatie.fr. 7 Paul Hirst and Grahame Thompson, Globalization

  19. Global Atmospheric Aerosol Modeling

    NASA Technical Reports Server (NTRS)

    Hendricks, Johannes; Aquila, Valentina; Righi, Mattia

    2012-01-01

    Global aerosol models are used to study the distribution and properties of atmospheric aerosol particles as well as their effects on clouds, atmospheric chemistry, radiation, and climate. The present article provides an overview of the basic concepts of global atmospheric aerosol modeling and shows some examples from a global aerosol simulation. Particular emphasis is placed on the simulation of aerosol particles and their effects within global climate models.

  20. Transitional Division Algorithms.

    ERIC Educational Resources Information Center

    Laing, Robert A.; Meyer, Ruth Ann

    1982-01-01

    A survey of general mathematics students whose teachers were taking an inservice workshop revealed that they had not yet mastered division. More direct introduction of the standard division algorithm is favored in elementary grades, with instruction of transitional processes curtailed. Weaknesses in transitional algorithms appear to outweigh…

  1. Expanding Views on Transition.

    ERIC Educational Resources Information Center

    Repetto, Jeanne B.; Correa, Vivian I.

    1996-01-01

    This position paper proposes an expanded definition of transition, based on common components of early childhood and secondary perspectives. It advocates for a seamless model of transition service delivery for students with disabilities, including program planning, from birth through age 21. The model addresses curriculum, location of services,…

  2. Transition to Living.

    ERIC Educational Resources Information Center

    Repetto, Jeanne B.

    2003-01-01

    Discussion of transition for students with disabilities emphasizes transition skills needed for life beyond work. The importance of assisting students in planning for their life roles as workers, family members, friends, consumers, and community members is discussed. Suggestions are offered to better prepare students for all their life roles by…

  3. Modeling the transition region

    NASA Astrophysics Data System (ADS)

    Singer, Bart A.

    1994-04-01

    The calculation of engineering flows undergoing laminar-turbulent transition presents special problems. Mean-flow quantities obey neither the fully laminar nor the fully turbulent correlations. In addition, local maxima in skin friction, wall temperature, and heat transfer often occur near the end of the transition region. Traditionally, modeling this region has been important for the design of turbine blades, where the transition region is long in relation to the chord length of the blade. More recently, the need for better transition-region models has been recognized by designers of hypersonic vehicles where the high Mach number, the low Reynolds number, and the low-disturbance flight environment emphasize the importance of the transition region. Needless to say, a model that might work well for the transitional flows typically found in gas turbines will not necessarily work well for the external surface of a hypersonic vehicle. In Section 2 of this report, some of the important flow features that control the transition region will be discussed. In Section 3, different approaches to the modeling problem will be summarized and cataloged. Fully turbulent flow models will be discussed in detail in Section 4; models specifically designed for transitional flow, in Section 5; and the evaluation of models, in Section 6.

  4. Seamless Transition for All

    ERIC Educational Resources Information Center

    Test, David W.

    2008-01-01

    Postschool outcomes for students with disabilities have been dismal for quite some time now. Although recent data from the National Longitudinal Transition Study 2 indicate some improvement, students with severe intellectual disabilities continue to transition into segregated employment at unacceptable rates in spite of a multitude of studies,…

  5. Transitioning between Clerkship Directors

    ERIC Educational Resources Information Center

    Soltys, Stephen M.; Pary, Robert J.; Robinson, Stephen W.; Markwell, Stephen J.

    2011-01-01

    Objective: The authors report on succession-planning for mid-level academic positions. Method: The authors describe the process of succession-planning between clerkship directors and the smooth transition resulting in one case. Results: Gradually transitioning allowed a new faculty person to assume the clerkship-director position with minimal…

  6. Transitions in Spousal Caregiving.

    ERIC Educational Resources Information Center

    Burton, Lynda C.; Zdaniuk, Bozena; Schulz, Richard; Jackson, Sharon; Hirsch, Calvin

    2003-01-01

    Describes transitions over 5 years among community-dwelling elderly spouses into and within caregiving roles and associated health outcomes. The trajectory of health outcomes associated with caregiving was generally downward. Those who transitioned to heavy caregiving had more symptoms of depression, and poorer self-reported health and health…

  7. Transitivity of Preferences

    ERIC Educational Resources Information Center

    Regenwetter, Michel; Dana, Jason; Davis-Stober, Clintin P.

    2011-01-01

    Transitivity of preferences is a fundamental principle shared by most major contemporary rational, prescriptive, and descriptive models of decision making. To have transitive preferences, a person, group, or society that prefers choice option "x" to "y" and "y" to "z" must prefer "x" to…

  8. Good Transitions = Great Starts!

    ERIC Educational Resources Information Center

    Our Children: The National PTA Magazine, 2012

    2012-01-01

    The smooth transition of outgoing and incoming board members and officers is of vital importance and can determine the PTA's success for years to come. The transition process is the responsibility of both incoming and outgoing officers and board members. It gives closure to those leaving their positions and allows those coming in to be properly…

  9. Transition Coordinators: Define Yourselves.

    ERIC Educational Resources Information Center

    Asselin, Susan B.; Todd-Allen, Mary; deFur, Sharon

    1998-01-01

    Describes a technique that was used successfully to identify the changing roles and responsibilities of special educators as transition coordinators. The Developing a Curriculum (DACUM) model uses people who are currently working in the occupation to define job responsibilities. The duties of a transition coordinator are identified. (CR)

  10. Matter in transition

    SciTech Connect

    Anderson, Lara B.; Gray, James; Raghuram, Nikhil; Taylor, Washington

    2016-04-13

    In this study, we explore a novel type of transition in certain 6D and 4D quantum field theories, in which the matter content of the theory changes while the gauge group and other parts of the spectrum remain invariant. Such transitions can occur, for example, for SU(6) and SU(7) gauge groups, where matter fields in a three-index antisymmetric representation and the fundamental representation are exchanged in the transition for matter in the two-index antisymmetric representation. These matter transitions are realized by passing through superconformal theories at the transition point. We explore these transitions in dual F-theory and heterotic descriptions, where a number of novel features arise. For example, in the heterotic description the relevant 6D SU(7) theories are described by bundles on K3 surfaces where the geometry of the K3 is constrained in addition to the bundle structure. On the F-theory side, non-standard representations such as the three-index antisymmetric representation of SU(N) require Weierstrass models that cannot be realized from the standard SU(N) Tate form. We also briefly describe some other situations, with groups such as Sp(3), SO(12), and SU(3), where analogous matter transitions can occur between different representations. For SU(3), in particular, we find a matter transition between adjoint matter and matter in the symmetric representation, giving an explicit Weierstrass model for the F-theory description of the symmetric representation that complements another recent analogous construction.

  11. Mapping Global Citizenship

    ERIC Educational Resources Information Center

    Stein, Sharon

    2015-01-01

    The demand to cultivate global citizenship is frequently invoked as central to colleges' and universities' internationalization efforts. However, the term "global citizenship" remains undertheorized in the context of U.S. higher education. This article maps and engages three common global citizenship positions--entrepreneurial, liberal…

  12. Global Governance, Educational Change

    ERIC Educational Resources Information Center

    Mundy, Karen

    2007-01-01

    In the last half decade, a rising literature has focused on the idea that processes of economic, political and social globalization require analysis in terms of governance at the global level. It is argued in this article that emerging forms of global governance have produced significant challenges to conventional conceptions of international…

  13. Globalization Takes Off.

    ERIC Educational Resources Information Center

    Braun, Tibor

    1998-01-01

    Analysis of the Social Sciences Citation Index (SSCI) database determined the growth of frequency of use of the term globalization during 1989-1995. Lists globalized items during 1989-1995: business, industry, production, and technology. Notes that science has not become globalized because it is still supported and managed by national governments.…

  14. Developing Successful Global Leaders

    ERIC Educational Resources Information Center

    Training, 2011

    2011-01-01

    Everyone seems to agree the world desperately needs strong leaders who can manage a global workforce and all the inherent challenges that go with it. That's a big part of the raison d'etre for global leadership development programs. But are today's organizations fully utilizing these programs to develop global leaders, and, if so, are they…

  15. An Attainable Global Perspective.

    ERIC Educational Resources Information Center

    de Castaneda, Viann Pedersen

    Concordia College (Minnesota) has established a global studies curriculum that encourages the development of a global perspective in future business leaders. Global perspective is seen as having five dimensions: (1) perspective consciousness; (2) "state of the planet" awareness; (3) cross-cultural awareness; (4) knowledge of global…

  16. The Global Positioning System

    DTIC Science & Technology

    1989-05-01

    Global Positioning System ( GPS ) and current program status are provided. The importance of...the NAVSTAR Global Positioning System (NAVSTAR GPS or GPS ) will have on future weapons employment. The study will: examine why we need a high...Washington, D.C., 24 January, 1984. Malone, Daniel K. GPS /NAVSTAR. Military Review, March 1986. Nepean, Phillip The NAVSTAR Global Positioning System

  17. Global Cancer Humanitarian Award

    Cancer.gov

    Pat Garcia-Gonzalez of the Max Foundation accepted the first annual NCI Global Cancer Medicine Humanitarian Award for her work in chronic myeloid leukemia at the NCI, Center for Global Health Symposium for Global Cancer Research, held in Boston on March 25, 2015.

  18. Globalization and American Education

    ERIC Educational Resources Information Center

    Merriman, William; Nicoletti, Augustine

    2008-01-01

    Globalization is a potent force in today's world. The welfare of the United States is tied to the welfare of other countries by economics, the environment, politics, culture, information, and technology. This paper identifies the implications of globalization for education, presents applications of important aspects of globalization that teachers…

  19. Global Health and the Global Economic Crisis

    PubMed Central

    Gill, Stephen; Bakker, Isabella

    2011-01-01

    Although the resources and knowledge for achieving improved global health exist, a new, critical paradigm on health as an aspect of human development, human security, and human rights is needed. Such a shift is required to sufficiently modify and credibly reduce the present dominance of perverse market forces on global health. New scientific discoveries can make wide-ranging contributions to improved health; however, improved global health depends on achieving greater social justice, economic redistribution, and enhanced democratization of production, caring social institutions for essential health care, education, and other public goods. As with the quest for an HIV vaccine, the challenge of improved global health requires an ambitious multidisciplinary research program. PMID:21330597

  20. Global sea level linked to global temperature

    PubMed Central

    Vermeer, Martin; Rahmstorf, Stefan

    2009-01-01

    We propose a simple relationship linking global sea-level variations on time scales of decades to centuries to global mean temperature. This relationship is tested on synthetic data from a global climate model for the past millennium and the next century. When applied to observed data of sea level and temperature for 1880–2000, and taking into account known anthropogenic hydrologic contributions to sea level, the correlation is >0.99, explaining 98% of the variance. For future global temperature scenarios of the Intergovernmental Panel on Climate Change's Fourth Assessment Report, the relationship projects a sea-level rise ranging from 75 to 190 cm for the period 1990–2100. PMID:19995972

  1. Towards mapping attenuation and water content in the Transition Zone

    NASA Astrophysics Data System (ADS)

    Savage, B. K.

    2013-12-01

    The mantle transition zone is suggested to play a significant role in water storage due to the high solubility of H2O in transition zone minerals. However, quantifying the water content of the transition zone has proven difficult. Previous investigations of the transition zone using a variety of techniques have identified variations in water content globally, associated melt at 400 km, and variable thickness. The resulting water distribution models indicate substantially different Earth models and subsequent seismic responses. Water enhances attenuation with minimal change to seismic wave speed in the transition zone. Taken in combination with correlated temperature induced wave speed / attenuation reductions, the water content and temperature in the transition zone can be inferred. Using upper mantle seismic phases that propagate within the transition zone, we can isolate the effects of attenuation, or anelasticity, and seismic wave speeds. Synthetic seismograms at high frequency, around 1 Hz, from models with a "wet" transition zone show a distinct amplitude reduction and phase delay. Conversely, models with melt on top of the transition zone produce a delayed, secondary arrival with an upper mantle moveout velocity. These diagnostic arrivals, based on synthetic seismic responses, are best identified at the end of the triplicated 660 km branch. Full modeling of the seismic phases from the transition zone will enable a mapping of water content and temperature, while deciphering how water is distributed and transported throughout the mantle.

  2. Global perspectives: A new global ethic, a new global partnership

    SciTech Connect

    Brundtland, G.H.

    1990-06-01

    In her keynote address at the opening plenary session of the Globe '90 Conference held in Vancouver in March, Mrs. Brundtland called for a new global partnership of government, industry, producers and consumers to meet present and future environmental challenges. This partnership would require help to developing countries to help free them from their handicaps of debt, overpopulation and poverty; that improvements made to the environment would not be offset by ecological damage in other areas. She was encouraged that the policy of sustainable development has been widely adapted as the only viable strategy for global change.

  3. [Globalization, poverty and health].

    PubMed

    Buss, Paulo Marchiori

    2007-01-01

    This paper analyses the relationship between globalization, poverty and health, defining and presenting the main characteristics of contemporary globalization. It also establishes the characteristics of poverty today, both globally and regionally. Reviewing articles and world reports, it presents a set of evidence on the relationships between globalization and poverty, as well as their influence on health. Furthermore, it presents the opportunities offered by globalization, through a series of worldwide initiatives prompted by actions among countries under the aegis of the United Nations in general and the WHO in particular, in addition to intergovernmental alliances and coalitions and other civil society representatives.

  4. Transition Implementation Guide. Instructor Materials.

    ERIC Educational Resources Information Center

    Boyer-Stephens, Arden, Ed.

    This transition model, called Guiding Education toward Adult Roles for Success (GEARS), provides a comprehensive framework from which transition services and programs can evolve. Three components of transition services are considered: transition partners, the transition process, and adult outcomes. After an introduction, the report's second…

  5. Global Collaborative STEM Education

    NASA Astrophysics Data System (ADS)

    Meabh Kelly, Susan; Smith, Walter

    2016-04-01

    Global Collaborative STEM Education, as the name suggests, simultaneously supports two sets of knowledge and skills. The first set is STEM -- science, technology, engineering and math. The other set of content knowledge and skills is that of global collaboration. Successful global partnerships require awareness of one's own culture, the biases embedded within that culture, as well as developing awareness of the collaborators' culture. Workforce skills fostered include open-mindedness, perseverance when faced with obstacles, and resourceful use of technological "bridges" to facilitate and sustain communication. In respect for the 2016 GIFT Workshop focus, Global Collaborative STEM Education projects dedicated to astronomy research will be presented. The projects represent different benchmarks within the Global Collaborative STEM Education continuum, culminating in an astronomy research experience that fully reflects how the global STEM workforce collaborates. To facilitate wider engagement in Global Collaborative STEM Education, project summaries, classroom resources and contact information for established international collaborative astronomy research projects will be disseminated.

  6. Extrasolar Planetary Transits

    NASA Astrophysics Data System (ADS)

    Cameron, Andrew Collier

    An extrasolar planet will transit the visible hemisphere of its host star if its orbital plane lies sufficiently close to the observer's line of sight. The resulting periodic dips in stellar flux reveal key system parameters, including the density of the host star and, if radial-velocity observations are available, the surface gravitational acceleration of the planet. In this chapter I present the essential methodology for modelling the time-dependent flux variation during a transit, and its use in determining the posterior probability distribution for the physical parameters of the system. Large-scale searches for transiting systems are an efficient way of discovering planets whose bulk densities, and hence compositions, can be accessed if their masses can also be determined. I present algorithms for detrending large ensembles of light curves, for searching for transit-like signals among them. I also discuss methods for identifying diluted stellar eclipsing binaries mimicking planetary transit signals, and validation of transit candidates too faint for radial-velocity follow-up. I review the use of time-resolved spectrophotometry and high-resolution spectroscopy during transits to identify the molecular constituents of exoplanetary atmospheres.

  7. Predictability of critical transitions

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaozhu; Kuehn, Christian; Hallerberg, Sarah

    2015-11-01

    Critical transitions in multistable systems have been discussed as models for a variety of phenomena ranging from the extinctions of species to socioeconomic changes and climate transitions between ice ages and warm ages. From bifurcation theory we can expect certain critical transitions to be preceded by a decreased recovery from external perturbations. The consequences of this critical slowing down have been observed as an increase in variance and autocorrelation prior to the transition. However, especially in the presence of noise, it is not clear whether these changes in observation variables are statistically relevant such that they could be used as indicators for critical transitions. In this contribution we investigate the predictability of critical transitions in conceptual models. We study the quadratic integrate-and-fire model and the van der Pol model under the influence of external noise. We focus especially on the statistical analysis of the success of predictions and the overall predictability of the system. The performance of different indicator variables turns out to be dependent on the specific model under study and the conditions of accessing it. Furthermore, we study the influence of the magnitude of transitions on the predictive performance.

  8. Future Earth - Research for Global Sustainability

    NASA Astrophysics Data System (ADS)

    Greenslade, Diana; Berkhout, Frans

    2014-05-01

    Future Earth is a 10-year international research programme that aims to provide the critical knowledge required for societies to understand and address challenges posed by global environmental change (GEC) and to seize opportunities for transitions to global sustainability. Future Earth research is organised around three broad and integrated research themes: Dynamic Planet; Global Development; and Transformations towards Sustainability. It builds upon and integrates the existing GEC Programmes: World Climate Research Programme (WCRP), the International Geosphere-Biosphere Programme (IGBP), DIVERSITAS (international programme of biodiversity science), the International Human Dimensions Programme (IHDP) and the Earth Systems Science Partnership (ESSP). This presentation will outline the key principles of Future Earth, such as the integration of natural and social science, and will describe how the programme intends to address the challenges of global environmental change. Some of the major research questions addressed by Future Earth could include: further understanding of the dynamics of the Earth system (including socio-ecology); risks relating to tipping points; how to ensure sustainable access to food, water and energy; and whether the present economic system provides the necessary framework for low carbon transition.

  9. Global Health Governance at a Crossroads

    PubMed Central

    Ng, Nora Y.; Ruger, Jennifer Prah

    2014-01-01

    This review takes stock of the global health governance (GHG) literature. We address the transition from international health governance (IHG) to global health governance, identify major actors, and explain some challenges and successes in GHG. We analyze the framing of health as national security, human security, human rights, and global public good, and the implications of these various frames. We also establish and examine from the literature GHG’s major themes and issues, which include: 1) persistent GHG problems; 2) different approaches to tackling health challenges (vertical, horizontal, and diagonal); 3) health’s multisectoral connections; 4) neoliberalism and the global economy; 5) the framing of health (e.g. as a security issue, as a foreign policy issue, as a human rights issue, and as a global public good); 6) global health inequalities; 7) local and country ownership and capacity; 8) international law in GHG; and 9) research gaps in GHG. We find that decades-old challenges in GHG persist and GHG needs a new way forward. A framework called shared health governance offers promise. PMID:24729828

  10. Global Health Governance at a Crossroads.

    PubMed

    Ng, Nora Y; Ruger, Jennifer Prah

    2011-06-21

    This review takes stock of the global health governance (GHG) literature. We address the transition from international health governance (IHG) to global health governance, identify major actors, and explain some challenges and successes in GHG. We analyze the framing of health as national security, human security, human rights, and global public good, and the implications of these various frames. We also establish and examine from the literature GHG's major themes and issues, which include: 1) persistent GHG problems; 2) different approaches to tackling health challenges (vertical, horizontal, and diagonal); 3) health's multisectoral connections; 4) neoliberalism and the global economy; 5) the framing of health (e.g. as a security issue, as a foreign policy issue, as a human rights issue, and as a global public good); 6) global health inequalities; 7) local and country ownership and capacity; 8) international law in GHG; and 9) research gaps in GHG. We find that decades-old challenges in GHG persist and GHG needs a new way forward. A framework called shared health governance offers promise.

  11. Variational Transition State Theory

    SciTech Connect

    Truhlar, Donald G.

    2016-09-29

    This is the final report on a project involving the development and applications of variational transition state theory. This project involved the development of variational transition state theory for gas-phase reactions, including optimized multidimensional tunneling contributions and the application of this theory to gas-phase reactions with a special emphasis on developing reaction rate theory in directions that are important for applications to combustion. The development of variational transition state theory with optimized multidimensional tunneling as a useful computational tool for combustion kinetics involved eight objectives.

  12. Transition nozzle combustion system

    DOEpatents

    Kim, Won-Wook; McMahan, Kevin Weston; Maldonado, Jaime Javier

    2016-11-29

    The present application provides a combustion system for use with a cooling flow. The combustion system may include a head end, an aft end, a transition nozzle extending from the head end to the aft end, and an impingement sleeve surrounding the transition nozzle. The impingement sleeve may define a first cavity in communication with the head end for a first portion of the cooling flow and a second cavity in communication with the aft end for a second portion of the cooling flow. The transition nozzle may include a number of cooling holes thereon in communication with the second portion of the cooling flow.

  13. Holographic magnetic phase transition

    SciTech Connect

    Lifschytz, Gilad; Lippert, Matthew

    2009-09-15

    We study four-dimensional interacting fermions in a strong magnetic field, using the holographic Sakai-Sugimoto model of intersecting D4- and D8-branes in the deconfined, chiral-symmetric parallel phase. We find that as the magnetic field is varied, while staying in the parallel phase, the fermions exhibit a first-order phase transition in which their magnetization jumps discontinuously. Properties of this transition are consistent with a picture in which some of the fermions jump to the lowest Landau level. Similarities to known magnetic phase transitions are discussed.

  14. Global warming without global mean precipitation increase?

    PubMed Central

    Salzmann, Marc

    2016-01-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K−1 decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge. PMID:27386558

  15. Global warming without global mean precipitation increase?

    PubMed

    Salzmann, Marc

    2016-06-01

    Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K(-1) decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge.

  16. Superconductivity in transition metals.

    PubMed

    Slocombe, Daniel R; Kuznetsov, Vladimir L; Grochala, Wojciech; Williams, Robert J P; Edwards, Peter P

    2015-03-13

    A qualitative account of the occurrence and magnitude of superconductivity in the transition metals is presented, with a primary emphasis on elements of the first row. Correlations of the important parameters of the Bardeen-Cooper-Schrieffer theory of superconductivity are highlighted with respect to the number of d-shell electrons per atom of the transition elements. The relation between the systematics of superconductivity in the transition metals and the periodic table high-lights the importance of short-range or chemical bonding on the remarkable natural phenomenon of superconductivity in the chemical elements. A relationship between superconductivity and lattice instability appears naturally as a balance and competition between localized covalent bonding and so-called broken covalency, which favours d-electron delocalization and superconductivity. In this manner, the systematics of superconductivity and various other physical properties of the transition elements are related and unified.

  17. Coping with Transitions.

    ERIC Educational Resources Information Center

    Bendersky, Nora; And Others

    1984-01-01

    Describes a workshop for nine South American students at the Hebrew University of Jerusalem. The two-day session focussed on exploring coping behaviors that could help students adjust to transitions. (JAC)

  18. Transit Timing Variations

    NASA Video Gallery

    The animation shows the difference between planet transit timing of single and multiple planet system. In tightly packed planetary systems, the gravitational pull of the planets among themselves ca...

  19. Oligocyclopentadienyl transition metal complexes

    SciTech Connect

    de Azevedo, Cristina G.; Vollhardt, K. Peter C.

    2002-01-18

    Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

  20. Alternative fuel transit buses

    SciTech Connect

    Motta, R.; Norton, P.; Kelly, K.

    1996-10-01

    The National Renewable Energy Laboratory (NREL) is a U.S. Department of Energy (DOE) national laboratory; this project was funded by DOE. One of NREL`s missions is to objectively evaluate the performance, emissions, and operating costs of alternative fuel vehicles so fleet managers can make informed decisions when purchasing them. Alternative fuels have made greater inroads into the transit bus market than into any other. Each year, the American Public Transit Association (APTA) surveys its members on their inventory and buying plans. The latest APTA data show that about 4% of the 50,000 transit buses in its survey run on an alternative fuel. Furthermore, 1 in 5 of the new transit buses that members have on order are alternative fuel buses. This program was designed to comprehensively and objectively evaluate the alternative fuels in use in the industry.

  1. Palaeontology: turtles in transition.

    PubMed

    Lee, Michael S Y

    2013-06-17

    One of the major remaining gaps in the vertebrate fossil record concerns the origin of turtles. The enigmatic little reptile Eunotosaurus could represent an important transitional form, as it has a rudimentary shell that resembles the turtle carapace.

  2. Urban guideway transit workshop: Proceedings

    SciTech Connect

    Larsen, H. )

    1992-03-01

    On March 20--21, 1991, EPRI sponsored a workshop on urban guideway transit. The purpose of this workshop was to provide utility managers with increased knowledge about urban guideway transit options, public policy regarding transit, and the effect of transit options on utility operations. With this information utilities should be better prepared to make decisions about transit development in their service areas. The workshop also provided EPRI with ideas and information for developing an R D project plan for urban guideway transit.

  3. Global diets link environmental sustainability and human health

    NASA Astrophysics Data System (ADS)

    Tilman, David; Clark, Michael

    2014-11-01

    Diets link environmental and human health. Rising incomes and urbanization are driving a global dietary transition in which traditional diets are replaced by diets higher in refined sugars, refined fats, oils and meats. By 2050 these dietary trends, if unchecked, would be a major contributor to an estimated 80 per cent increase in global agricultural greenhouse gas emissions from food production and to global land clearing. Moreover, these dietary shifts are greatly increasing the incidence of type II diabetes, coronary heart disease and other chronic non-communicable diseases that lower global life expectancies. Alternative diets that offer substantial health benefits could, if widely adopted, reduce global agricultural greenhouse gas emissions, reduce land clearing and resultant species extinctions, and help prevent such diet-related chronic non-communicable diseases. The implementation of dietary solutions to the tightly linked diet-environment-health trilemma is a global challenge, and opportunity, of great environmental and public health importance.

  4. Global diets link environmental sustainability and human health.

    PubMed

    Tilman, David; Clark, Michael

    2014-11-27

    Diets link environmental and human health. Rising incomes and urbanization are driving a global dietary transition in which traditional diets are replaced by diets higher in refined sugars, refined fats, oils and meats. By 2050 these dietary trends, if unchecked, would be a major contributor to an estimated 80 per cent increase in global agricultural greenhouse gas emissions from food production and to global land clearing. Moreover, these dietary shifts are greatly increasing the incidence of type II diabetes, coronary heart disease and other chronic non-communicable diseases that lower global life expectancies. Alternative diets that offer substantial health benefits could, if widely adopted, reduce global agricultural greenhouse gas emissions, reduce land clearing and resultant species extinctions, and help prevent such diet-related chronic non-communicable diseases. The implementation of dietary solutions to the tightly linked diet-environment-health trilemma is a global challenge, and opportunity, of great environmental and public health importance.

  5. Bridging the Transition Gap

    DTIC Science & Technology

    2013-05-23

    state and prevent instability agents from establishing 3Nicholas J. Armstrong and Jacqueline Chura-Beaver, Harnessing Post-Conflict Transition: A...reassessing the transition period with a wider range of stakeholder begins with a communal understanding of 118George K. Tanham, War without Guns ...Future.” Military Review (March/April 2006): 11. Armstrong, Nicholas J., and Jacqueline Chura-Beaver. Harnessing Post-Conflict. Carlisle, PA

  6. Quantum Phase Transitions

    DTIC Science & Technology

    2011-05-01

    Park, NC 27709-2211 15. SUBJECT TERMS Quantum Thoery Phase transitions Subir Sachdev Harvard University Office of Sponsored Research 1350...magnetism, and solvable models obtained from string theory. After introducing the basic theory, it moves on to a detailed description of the canonical...students and researchers in condensed matter physics and particle and string theory. Print | Close Quantum Phase Transitions 2nd Edition Subir Sachdev

  7. Matter in transition

    DOE PAGES

    Anderson, Lara B.; Gray, James; Raghuram, Nikhil; ...

    2016-04-13

    In this study, we explore a novel type of transition in certain 6D and 4D quantum field theories, in which the matter content of the theory changes while the gauge group and other parts of the spectrum remain invariant. Such transitions can occur, for example, for SU(6) and SU(7) gauge groups, where matter fields in a three-index antisymmetric representation and the fundamental representation are exchanged in the transition for matter in the two-index antisymmetric representation. These matter transitions are realized by passing through superconformal theories at the transition point. We explore these transitions in dual F-theory and heterotic descriptions, wheremore » a number of novel features arise. For example, in the heterotic description the relevant 6D SU(7) theories are described by bundles on K3 surfaces where the geometry of the K3 is constrained in addition to the bundle structure. On the F-theory side, non-standard representations such as the three-index antisymmetric representation of SU(N) require Weierstrass models that cannot be realized from the standard SU(N) Tate form. We also briefly describe some other situations, with groups such as Sp(3), SO(12), and SU(3), where analogous matter transitions can occur between different representations. For SU(3), in particular, we find a matter transition between adjoint matter and matter in the symmetric representation, giving an explicit Weierstrass model for the F-theory description of the symmetric representation that complements another recent analogous construction.« less

  8. Make Locally and Sell Globally

    SciTech Connect

    Majumdar, Arun

    2011-08-15

    The world is in transition and is offering possibly the biggest economic opportunity of the 21st century. The question is: Can we grab it? I believe we can, but we need to be both smart and strategic about it. Let me explain this through a macro-picture and some global trends. First, the long-term trend shows that the global economy (1) will undergo steady growth and, on average, people’s income levels and buying power will rise around the world. This prosperity is the good news. History tells us, however, that consequently in many countries, energy use per person is likely to rise as well (2), especially for developing economies. Access to affordable energy supply as well as their environmental impact poses many risks. Second, the world population is also growing from 6.5 billion people today to almost double by the end of the century, mostly in developing economies. This dual growth of population and the economy suggests that the total world energy demand will very likely increase steadily.

  9. The new global health.

    PubMed

    De Cock, Kevin M; Simone, Patricia M; Davison, Veronica; Slutsker, Laurence

    2013-08-01

    Global health reflects the realities of globalization, including worldwide dissemination of infectious and noninfectious public health risks. Global health architecture is complex and better coordination is needed between multiple organizations. Three overlapping themes determine global health action and prioritization: development, security, and public health. These themes play out against a background of demographic change, socioeconomic development, and urbanization. Infectious diseases remain critical factors, but are no longer the major cause of global illness and death. Traditional indicators of public health, such as maternal and infant mortality rates no longer describe the health status of whole societies; this change highlights the need for investment in vital registration and disease-specific reporting. Noncommunicable diseases, injuries, and mental health will require greater attention from the world in the future. The new global health requires broader engagement by health organizations and all countries for the objectives of health equity, access, and coverage as priorities beyond the Millennium Development Goals are set.

  10. The New Global Health

    PubMed Central

    Simone, Patricia M.; Davison, Veronica; Slutsker, Laurence

    2013-01-01

    Global health reflects the realities of globalization, including worldwide dissemination of infectious and noninfectious public health risks. Global health architecture is complex and better coordination is needed between multiple organizations. Three overlapping themes determine global health action and prioritization: development, security, and public health. These themes play out against a background of demographic change, socioeconomic development, and urbanization. Infectious diseases remain critical factors, but are no longer the major cause of global illness and death. Traditional indicators of public health, such as maternal and infant mortality rates no longer describe the health status of whole societies; this change highlights the need for investment in vital registration and disease-specific reporting. Noncommunicable diseases, injuries, and mental health will require greater attention from the world in the future. The new global health requires broader engagement by health organizations and all countries for the objectives of health equity, access, and coverage as priorities beyond the Millennium Development Goals are set. PMID:23876365

  11. Globalization, culture and psychology.

    PubMed

    Melluish, Steve

    2014-10-01

    This article outlines the cultural and psychological effects of globalization. It looks at the impact of globalization on identity; ideas of privacy and intimacy; the way we understand and perceive psychological distress; and the development of the profession of psychology around the world. The article takes a critical perspective on globalization, seeing it as aligned with the spread of neoliberal capitalism, a tendency towards cultural homogenization, the imposition of dominant 'global north' ideas and the resultant growing inequalities in health and well-being. However, it also argues that the increased interconnectedness created by globalization allows for greater acknowledgement of our common humanity and for collective efforts to be developed to tackle what are increasingly global problems. This requires the development of more nuanced understandings of cultural differences and of indigenous psychologies.

  12. Global health for a globally minded president.

    PubMed

    Daulaire, Nils

    2009-01-01

    President-elect Barack Obama can build on historic initiatives championed by his predecessor in global AIDS and malaria. These should serve as the platform for a more comprehensive and evidence-based set of activities aimed at addressing the major causes of ill health and instability in low-income countries. Obama should launch a new Global Family Health Action Plan aimed at saving the lives of six million children and women annually in impoverished nations. Existing policies driven by U.S. domestic ideological battles, particularly those relating to sexual and reproductive health, should be revised and brought into line with solid science and evidence from the field.

  13. Wideband Global SATCOM (WGS)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-326 Wideband Global SATCOM (WGS) As of FY 2017 President’s Budget Defense Acquisition...Wideband Global SATCOM (WGS) DoD Component Air Force Responsible Office References SAR Baseline (Production Estimate) Defense Acquisition...Program Baseline (APB) dated March 12, 2014 WGS December 2015 SAR March 23, 2016 16:19:48 UNCLASSIFIED 5 Mission and Description Wideband Global

  14. NAVSTAR Global Positioning System.

    DTIC Science & Technology

    1988-04-01

    number) The NAVSTAR Global Positioning System ( GPS ) is an all-weather, Jam-resistant, continuous-operations space-based, passive radio navigation and...with an understanding of the capabilities and limitations of the NAVSTAR Global Positioning System ( GPS ). II. Problem: To fight the next battle...navigation equipment and was not able to navigate on instruments or across a distant 9000-foot mountain. Had a NAVSTAR Global Positioning System ( GPS

  15. Global desertification: Drivers and feedbacks

    NASA Astrophysics Data System (ADS)

    D'Odorico, Paolo; Bhattachan, Abinash; Davis, Kyle F.; Ravi, Sujith; Runyan, Christiane W.

    2013-01-01

    Desertification is a change in soil properties, vegetation or climate, which results in a persistent loss of ecosystem services that are fundamental to sustaining life. Desertification affects large dryland areas around the world and is a major cause of stress in human societies. Here we review recent research on the drivers, feedbacks, and impacts of desertification. A multidisciplinary approach to understanding the drivers and feedbacks of global desertification is motivated by our increasing need to improve global food production and to sustainably manage ecosystems in the context of climate change. Classic desertification theories look at this process as a transition between stable states in bistable ecosystem dynamics. Climate change (i.e., aridification) and land use dynamics are the major drivers of an ecosystem shift to a “desertified” (or “degraded”) state. This shift is typically sustained by positive feedbacks, which stabilize the system in the new state. Desertification feedbacks may involve land degradation processes (e.g., nutrient loss or salinization), changes in rainfall regime resulting from land-atmosphere interactions (e.g., precipitation recycling, dust emissions), or changes in plant community composition (e.g., shrub encroachment, decrease in vegetation cover). We analyze each of these feedback mechanisms and discuss their possible enhancement by interactions with socio-economic drivers. Large scale effects of desertification include the emigration of “environmental refugees” displaced from degraded areas, climatic changes, and the alteration of global biogeochemical cycles resulting from the emission and long-range transport of fine mineral dust. Recent research has identified some possible early warning signs of desertification, which can be used as indicators of resilience loss and imminent shift to desert-like conditions. We conclude with a brief discussion on some desertification control strategies implemented in different

  16. 4DVAR for Global Atmospheric Numerical Weather Prediction

    DTIC Science & Technology

    2016-06-07

    generation global atmospheric 4D variational (4DVAR) data assimilation system, NAVDAS-AR2. OBJECTIVES The objective of this project is to construct...and transition a 4DVAR global atmospheric data assimilation system for NOGAPS to the Fleet Numerical Meteorology and Oceanography Center (FNMOC...This system, NAVDAS-AR, represents the first operational, weak constraint, 4DVAR atmospheric data assimilation system in the world. In this context

  17. NASA Global Hawk Overview

    NASA Technical Reports Server (NTRS)

    Naftel, Chris

    2014-01-01

    The NASA Global Hawk Project is supporting Earth Science research customers. These customers include: US Government agencies, civilian organizations, and universities. The combination of the Global Hawks range, endurance, altitude, payload power, payload volume and payload weight capabilities separates the Global Hawk platform from all other platforms available to the science community. This presentation includes an overview of the concept of operations and an overview of the completed science campaigns. In addition, the future science plans, using the NASA Global Hawk System, will be presented.

  18. Global Rietveld Refinement

    PubMed Central

    Shankland, Kenneth

    2004-01-01

    Global optimisation methods of structure determination from powder diffraction data have risen to prominence in a relatively short space of time and they now constitute a key approach in the examination of polycrystalline molecular organic materials. A correctly formulated global optimisation approach may be regarded as a “global Rietveld refinement” that is capable of delivering accurate crystal structures from high-quality powder diffraction data. This paper focuses on how accuracy at all stages of a powder diffraction experiment impacts upon the overall structure solution process and particular attention is paid to assessing the degree of accuracy with which structures are returned from the global optimisation process. PMID:27366603

  19. Global water cycle

    NASA Technical Reports Server (NTRS)

    Robertson, Franklin; Goodman, Steven J.; Christy, John R.; Fitzjarrald, Daniel E.; Chou, Shi-Hung; Crosson, William; Wang, Shouping; Ramirez, Jorge

    1993-01-01

    This research is the MSFC component of a joint MSFC/Pennsylvania State University Eos Interdisciplinary Investigation on the global water cycle extension across the earth sciences. The primary long-term objective of this investigation is to determine the scope and interactions of the global water cycle with all components of the Earth system and to understand how it stimulates and regulates change on both global and regional scales. Significant accomplishments in the past year are presented and include the following: (1) water vapor variability; (2) multi-phase water analysis; (3) global modeling; and (4) optimal precipitation and stream flow analysis and hydrologic processes.

  20. Future Global Cryosphere: Impacts of Global Warming

    NASA Astrophysics Data System (ADS)

    Gan, T. Y.; Barry, R. G.

    2014-12-01

    In recent years, the Earth is undergoing potentially rapid changes in all cryospheric components, including Arctic sea ice shrinkage, mountain glacier recession, thawing permafrost, diminishing snow cover, and accelerated melting of the Greenland ice sheet. This has significant implications for global climate, hydrology, water resources, and global sea level. Physical evidences of changes observed in the cryosphere are: (a) Duration of ice cover of rivers and lakes in high latitudes of N. H. decreased by about two weeks over the 20th Century; (b) Significant retreat of glaciers world wide during the 20th Century; (c) Thinning of Arctic sea-ice extent and thickness by about 40% in late summer in recent decades, with the minimum sea ice concentration mapped by the SSM/I sensor of NASA in 2007; (d) Snow cover decreased in area by about 10% since global observations by satellites began in the late 1960s, in various places of the Northern Hemisphere; (e) In North America, snow water equivalent decreased by about 10mm since observations by passive microwave sensors began in the late 1970s; (f) Degradations of permafrost have been detected in some parts of the polar and sub-polar regions, and (g) The total 20th Century global average sea level rise was about 0.17m, likely due to decline in glaciers, snow, ice sheets, and losses from Greenland and Antarctica ice. Next, projected changes to the Cryosphere: northern hemisphere snow cover, avalanches, land ice, permafrost, freshwater ice, and sea ice changes, are presented.

  1. From Global Knowledge to Global Civic Engagement

    ERIC Educational Resources Information Center

    Lorenzini, Michelle

    2013-01-01

    In this article, I argue that student learning is enhanced when civic engagement is a component of international education initiatives. When only presented with knowledge about global challenges, students can become frustrated and overwhelmed unless they also understand how they might contribute to solutions. Political science programs are…

  2. "Global Competency" Is Imperative for Global Success

    ERIC Educational Resources Information Center

    Reimers, Fernando

    2009-01-01

    According to a recent report of scenarios prepared by the National Intelligence Council, the next 15 years will bring significant global changes, including the transformation of the international political system built after World War II, a transfer of wealth from the West to the East, pressure on natural resources resulting from continuing…

  3. Balancing global city with global village.

    PubMed

    Afshar, F

    1998-12-01

    The discourse on habitat and human settlements is increasingly dominated by that of the global, mega-city. If the aim of those of us in the human settlements field are to improve our understanding of and action on habitat and human settlements, this, often exclusive, focus is a mistake. Our habitat is better understood and acted upon as a network of interwoven settlements and surrounding countryside, large and small, themselves interwoven within our larger ecosystem. In this network the habitat of our smaller settlements (smaller cities, towns, villages) and rural areas and our global village also plays a critical role. The assumption can be challenged that urbanization and the mega-city are the critical issues of habitat and human settlements. Evidence suggests that with some rurbanization there is also counter urbanization, the ruralization of cities, and, perhaps most important, a growing urbanization as city-country interactions intensify. Habitat for all and habitat for a healthy, sustainable planet demands our openness to these new concepts and realities. It demands an integrated, balanced, approach which helps a wide range of living settlement nodes, large and small, to nurture each other. Global City and Global Village must go hand in hand. Our planetary and human health depends on it.

  4. Venus Transit 2004

    NASA Astrophysics Data System (ADS)

    Mayo, L. A.; Odenwald, S. F.

    2002-09-01

    December 6th, 1882 was the last transit of the planet Venus across the disk of the sun. It was heralded as an event of immense interest and importance to the astronomical community as well as the public at large. There have been only six such occurrences since Galileo first trained his telescope on the heavens in 1609 and on Venus in 1610 where he concluded that Venus had phases like the moon and appeared to get larger and smaller over time. Many historians consider this the final nail in the coffin of the Ptolemaic, Earth centered solar system. In addition, each transit has provided unique opportunities for discovery such as measurement and refinement of the astronomical unit, calculation of longitudes on the earth, and detection of Venus' atmosphere. The NASA Sun Earth Connection Education Forum in partnership with the Solar System Exploration Forum, DPS, and a number of NASA space missions is developing plans for an international education program centered around the June 8, 2004 Venus transit. The transit will be visible in its entirety from Europe and partially from the East Coast of the United States. We will use a series of robotic observatories including the Telescopes In Education network distributed in latitude to provide observations of the transit that will allow middle and high school students to calculate the A.U. through application of parallax. We will also use Venus transit as a probe of episodes in American history (e.g. 1769: revolutionary era, 1882: post civil war era, and 2004: modern era). Museums and planetariums in the US and Europe will offer real time viewing of the transit and conduct educational programs through professional development seminars, public lectures, and planetarium shows. We are interested in soliciting advice from the research community to coordinate professional research interests with this program.

  5. Phase transitions in fluids and biological systems

    NASA Astrophysics Data System (ADS)

    Sipos, Maksim

    In this thesis, I consider systems from two seemingly different fields: fluid dynamics and microbial ecology. In these systems, the unifying features are the existences of global non-equilibrium steady states. I consider generic and statistical models for transitions between these global states, and I relate the model results with experimental data. A theme of this thesis is that these rather simple, minimal models are able to capture a lot of functional detail about complex dynamical systems. In Part I, I consider the transition between laminar and turbulent flow. I find that quantitative and qualitative features of pipe flow experiments, the superexponential lifetime and the splitting of turbulent puffs, and the growth rate of turbulent slugs, can all be explained by a coarse-grained, phenomenological model in the directed percolation universality class. To relate this critical phenomena approach closer to the fluid dynamics, I consider the transition to turbulence in the Burgers equation, a simplified model for Navier-Stokes equations. Via a transformation to a model of directed polymers in a random medium, I find that the transition to Burgers turbulence may also be in the directed percolation universality class. This evidence implies that the turbulent-to-laminar transition is statistical in nature and does not depend on details of the Navier-Stokes equations describing the fluid flow. In Part II, I consider the disparate subject of microbial ecology where the complex interactions within microbial ecosystems produce observable patterns in microbe abundance, diversity and genotype. In order to be able to study these patterns, I develop a bioinformatics pipeline to multiply align and quickly cluster large microbial metagenomics datasets. I also develop a novel metric that quantifies the degree of interactions underlying the assembly of a microbial ecosystem, particularly the transition between neutral (random) and niche (deterministic) assembly. I apply this

  6. Health transition among Pacificans: unpacking imperialism.

    PubMed

    Finau, Sitaleki A; Wainiqolo, Iris L; Cuboni, Giuseppe G

    2002-09-01

    What and who defines health? In the Pacific at least, health is not only an individual's state of well-being. It also refers to the positive state of the social body i.e. how people within a community interact with each other and with their environment to produce positive and desired effects. Even death can be viewed as a positive stage in human life if it facilitates the achievement of well-being as one transit or translocates to the next stage of 'eternal bliss'. The pursuit of health and well-being has resulted in many challenges over time in many communities. Health transition has been seen as a phenomenon that can be defined by the various eras of disease occurrence. Various morbidity and mortality indicators are used to measure these. According to health transition theorists, this phenomenon is linear and similar for all societies. However, this linear approach is not cognizant of the many dimensions of social, mental, physical and spiritual well-being that encompasses the life and death of Pacificans. This paper attempts to tease out the various forces that have influenced the health transition phenomenon in the Pacific. Specifically, it argues that the forces of imperialism, colonialism and globalization have largely influenced health transition in the Pacific in a manner that is to some extent, both unfavorable and oppressive. It raises the difficulty of using morbidity and mortality as measures of transition in societies where people do not die but are believed to just translocate to another life. The paper ends by suggesting alternate ways of looking at the multidimensional processes of health changes in the Pacific.

  7. "Becoming Somebody": Youth Transitions through Education and Migration in Peru

    ERIC Educational Resources Information Center

    Crivello, Gina

    2011-01-01

    The past few decades have witnessed international pressure to get more children in the world educated, for longer. The view that school education is core to definitions of good childhoods and successful youth transitions is increasingly widespread, globally and locally. However, structural inequalities persist and migration for education has…

  8. Learning about the Importance of Education for Labour Market Transitions

    ERIC Educational Resources Information Center

    Oliver, Esther; Tellado, Itxaso; De Botton, Lena

    2014-01-01

    This article centres on the importance given by individuals to the process of education in labour market transitions and how they manage to overcome obstacles to achieve their goals. Many of the stories in the Spanish research were transformative and innovative despite the context of high levels of unemployment in Spain due to the global economic…

  9. Black Hole Advective Accretion Disks with Optical Depth Transition

    SciTech Connect

    Artemove, Y.V.; Bisnovatyi-Kogan, G.S.; Igumenshchev, I.V.; Novikov, I.D.

    2006-02-01

    We have constructed numerically global solutions of advective accretion disks around black holes that describe a continuous transition between the effectively optically thick outer and optically thin inner disk regions. We have concentrated on models of accretion flows with large mass accretion rates, and we have employed a bridging formula for radiative losses at high and low effective optical depths.

  10. Hypersonic Boundary-Layer Transition for X-33 Phase 2 Vehicle

    NASA Technical Reports Server (NTRS)

    Thompson, Richard A.; Hamilton, Harris H., II; Berry, Scott A.; Horvath, Thomas J.; Nowak, Robert J.

    1998-01-01

    A status review of the experimental and computational work performed to support the X-33 program in the area of hypersonic boundary-layer transition is presented. Global transition fronts are visualized using thermographic phosphor measurements. Results are used to derive transition correlations for "smooth body" and discrete roughness data and a computational tool is developed to predict transition onset for X-33 using these results. The X-33 thermal protection system appears to be conservatively designed for transition effects based on these studies. Additional study is needed to address concerns related to surface waviness. A discussion of future test plans is included.

  11. Learning to Plunder: Global Education, Global Inequality and the Global City

    ERIC Educational Resources Information Center

    Tannock, Stuart

    2010-01-01

    Most research and policy discussions of education in the global city have focused on the ways in which globalization and the emergence of global or globalizing cities can create social, economic and educational inequality locally, within the global city itself. Global cities, however, are, by definition, powerful places, where the core…

  12. Noise and Phase Transitions

    NASA Astrophysics Data System (ADS)

    Chen, Zhi; Yu, Clare C.

    2006-03-01

    Noise is present in many physical systems and is often viewed as a nuisance. Yet it can also be a probe of microscopic fluctuations. There have been indications recently that the noise in the resistivity increases in the vicinity of the metal-insulator transition. But what are the characteristics of the noise associated with well-understood first and second order phase transitions? It is well known that critical fluctuations are associated with second order phase transitions, but do these fluctuations lead to enhanced noise? We have addressed these questions using Monte Carlo simulations to study the noise in the 2D Ising model which undergoes a second order phase transition, and in the 5-state Potts model which undergoes a first order phase transition. We monitor these systems as the temperature drops below the critical temperature. At each temperature, after equilibration is established, we obtain the time series of quantities characterizing the properties of the system, i.e., the energy and magnetization per site. We apply different methods, such as the noise power spectrum, the Detrended Fluctuation Analysis (DFA) and the second spectrum of the noise, to analyze the fluctuations in these quantities.

  13. Examining hydrogen transitions.

    SciTech Connect

    Plotkin, S. E.; Energy Systems

    2007-03-01

    This report describes the results of an effort to identify key analytic issues associated with modeling a transition to hydrogen as a fuel for light duty vehicles, and using insights gained from this effort to suggest ways to improve ongoing modeling efforts. The study reported on here examined multiple hydrogen scenarios reported in the literature, identified modeling issues associated with those scenario analyses, and examined three DOE-sponsored hydrogen transition models in the context of those modeling issues. The three hydrogen transition models are HyTrans (contractor: Oak Ridge National Laboratory), MARKAL/DOE* (Brookhaven National Laboratory), and NEMS-H2 (OnLocation, Inc). The goals of these models are (1) to help DOE improve its R&D effort by identifying key technology and other roadblocks to a transition and testing its technical program goals to determine whether they are likely to lead to the market success of hydrogen technologies, (2) to evaluate alternative policies to promote a transition, and (3) to estimate the costs and benefits of alternative pathways to hydrogen development.

  14. RTGs on Transit

    NASA Astrophysics Data System (ADS)

    Dassoulas, John; McNutt, Ralph L.

    2007-01-01

    Transit, the US Navy's Navigation Satellite System was conceived at the Applied Physics Laboratory in 1957 by observing the Doppler shift while tracking Sputnik I. As spacecraft development proceeded there was concern about the ability of batteries to maintain the hermetic seal over a 5-year operational life requirement; therefore, alternate energy sources were investigated. The radioisotope thermoelectric generator (RTG) concept was pursued and resulted in the launch of SNAP 3s, providing partial power on both Transit 4A and 4B. SNAP 9s provided full power on three Transit 5BNs. All launches occurred in the early 1960s. When the U.S. conducted the high altitude nuclear test from Johnson Island, several spacecraft were lost due to artificial enhancement of charged particles in the Earth's magnetosphere resulting in rapid degradation of solar cell power production. This led to the decision to have both an RTG and Solar cell/battery design for Transit power systems; hence, a new RTG design, with a separable heat source and radiative coupling to the thermoelectric elements, was flown on TRIAD. This pioneering effort provided the impetus for future RTGs on interplanetary spacecraft. This paper describes the origin and purpose of the Transit program and provides details on the five satellites in that program that were powered by the first American RTGs used in space. The rationale and some of the challenges inherent in that use are also described.

  15. Globalization, Interdependence and Education

    ERIC Educational Resources Information Center

    Neubauer, Deane

    2007-01-01

    Contemporary globalization is marked by rapidly and dramatically increasing interdependence, which operates both within and among countries. Increasing global interdependence has profound influence on education at all levels, such as how to deal with a world with more permeable boundaries in which people are on the move more frequently (migration)…

  16. Global Wind Map

    ERIC Educational Resources Information Center

    Journal of College Science Teaching, 2005

    2005-01-01

    This brief article describes a new global wind-power map that has quantified global wind power and may help planners place turbines in locations that can maximize power from the winds and provide widely available low-cost energy. The researchers report that their study can assist in locating wind farms in regions known for strong and consistent…

  17. Assessing Individuals' Global Perspective

    ERIC Educational Resources Information Center

    Merrill, Kelly Carter; Braskamp, David C.; Braskamp, Larry A.

    2012-01-01

    This article introduces the Global Perspective Inventory (GPI), a survey instrument that measures participants' global perspective in terms of cognitive, intrapersonal, and interpersonal domains--each in terms of both development and acquisition. A summary of the recent research on the GPI is provided along with a discussion of potential uses.

  18. Global Awareness Test.

    ERIC Educational Resources Information Center

    Petrie, James

    The paper discusses the Global Awareness Test administered to 6,396 grade 9 students in New Brunswick, Canada at the beginning and end of the 1987 school year. The test was designed to better assess the impact of the grade 9 social studies program and the activities of New Brunswick's Global Education Centre. By comparing the results of the pre-…

  19. Building Global Learning Communities

    ERIC Educational Resources Information Center

    Cochrane, Thomas; Buchem, Ilona; Camacho, Mar; Cronin, Catherine; Gordon, Averill; Keegan, Helen

    2013-01-01

    Within the background where education is increasingly driven by the economies of scale and research funding, we propose an alternative online open and connected framework (OOC) for building global learning communities using mobile social media. We critique a three year action research case study involving building collaborative global learning…

  20. Teaching Global Society.

    ERIC Educational Resources Information Center

    Peet, Richard

    2002-01-01

    Describes the course, "Global Society," for first-year International Studies students at a Massachusetts liberal arts college. The course, which takes a historical approach, informs students about the nature, history, and present characteristics of the global system, taking theoretical, historical, and critical approaches that stress the…

  1. Global 2000 Countdown Kit.

    ERIC Educational Resources Information Center

    Zero Population Growth, Inc., Washington, DC.

    Fourteen units for high school global education classes are based on "The Global 2000 Report to the President," which examines the relationships between worldwide population growth and resource and environmental consequences. Topics of the units are population; income; food; fisheries; forests; water; nonfuel minerals; energy; impacts on…

  2. Global Diversity and Leadership.

    ERIC Educational Resources Information Center

    Ruiz, Art

    2003-01-01

    Argues that global diversity has become a business imperative in today's business climate. Global diversity is of core importance even for companies that are considered domestic. Suggests community colleges need help in understanding their customer base and their shifting values in order to meet their needs and win customer loyalty. (NB)

  3. The Global Youth Academy.

    ERIC Educational Resources Information Center

    Alschuler, Alfred; Myers, Stephen

    1995-01-01

    The Global Youth Academy began as a low-cost, private school that taught global citizenship to its own students and foreign students recruited enroute. The school-on-wings formula is simple: build the curriculum into a tour, integrate academic and personal growth, and stress community service. The program succeeds academically while promoting…

  4. An Attainable Global Perspective.

    ERIC Educational Resources Information Center

    Hanvey, Robert G.

    A more complete understanding of global perspective is provided in this essay through an examination of the modes of thought, sensitivities, intellectual skills, and explanatory capacities which contribute to the formation of a global perspective. With an emphasis on both a formal and informal educational level, the essay is divided into five…

  5. Simulating Global Climate Summits

    ERIC Educational Resources Information Center

    Vesperman, Dean P.; Haste, Turtle; Alrivy, Stéphane

    2014-01-01

    One of the most persistent and controversial issues facing the global community is climate change. With the creation of the UN Framework Convention on Climate Change (UNFCCC) in 1992 and the Kyoto Protocol (1997), the global community established some common ground on how to address this issue. However, the last several climate summits have failed…

  6. Preparing Global Citizens

    ERIC Educational Resources Information Center

    Roberts, Dennis C.; Welch, Lucas; Al-Khanji, Khalid

    2013-01-01

    Global citizens are those who are aware of, demonstrate respect for, and are comfortable engaging across cultural boundaries. This article explores why preparing global citizens is important and how positive psychology can inform our understanding of those who engage comfortably in today's complicated world. Soliya's Connect program is described…

  7. Poverty + Hunger = Global Issues.

    ERIC Educational Resources Information Center

    Schwartz, Richard H.

    1983-01-01

    Geography teachers can use mathematics to teach fourth, fifth, and sixth grade students about critical global issues. Five sample problems concerning population, poverty, waste, the arms race, and hunger are presented. The global issue related to each problem is discussed, and the solution and mathematical skill are provided. (RM)

  8. Translation as (Global) Writing

    ERIC Educational Resources Information Center

    Horner, Bruce; Tetreault, Laura

    2016-01-01

    This article explores translation as a useful point of departure and framework for taking a translingual approach to writing engaging globalization. Globalization and the knowledge economy are putting renewed emphasis on translation as a key site of contest between a dominant language ideology of monolingualism aligned with fast capitalist…

  9. Global Tuberculosis Report 2016

    MedlinePlus

    ... WHO Language عربي 中文 English Français Русский Español Tuberculosis (TB) Menu Tuberculosis The End TB Strategy Areas ... data News, events and features About us Global tuberculosis report 2016 WHO has published a global TB ...

  10. Defining Global Education

    ERIC Educational Resources Information Center

    Molina, Sarina; Lattimer, Heather

    2013-01-01

    As the world is becoming increasingly flat, it has become important for educators to prepare students to understand global perspectives and engage with people from countries and cultures around the world. Although there is no question as to the importance of global education to meet with the demands of a flat world, what internationalization and…

  11. Global Interaction in Design

    ERIC Educational Resources Information Center

    Bennett, Audrey Grace

    2010-01-01

    Based on a virtual conference, Glide'08 (Global Interaction in Design Education), that brought international design scholars together online, this special issue expands on the topics of cross-cultural communication and design and the technological affordances that support such interaction. The author discusses the need for global interaction in…

  12. Global and Local Textuality.

    ERIC Educational Resources Information Center

    Campbell, B. G.

    Coherence and cohesion are fundamental considerations of the composing process that help to define the global and local components of texuality. Global text coherence centers on those aspects of the familiar rhetorical situation. Coherence operates at the paragraph and essay levels, answering questions about focus, tone, mode, topic, and thesis.…

  13. Globalization of Management Education

    ERIC Educational Resources Information Center

    Bruner, Robert F.; Iannarelli, Juliane

    2011-01-01

    A new study, sponsored by the Association to Advance Collegiate Schools of Business, presented a comprehensive new perspective on the globalization of management education, (AACSB International, 2011). Its findings are sobering: with regard to emerging global trends in higher education and cross-border business, the report reveals a sizable gap…

  14. Critically Theorizing the Global

    ERIC Educational Resources Information Center

    Gaudelli, William

    2013-01-01

    Globalization has unleashed profound changes in education. These include positivistic international school comparisons, a singular focus on schools as drivers of economic development, and the adoption of neoliberal market principles in school. These changes, however, generally go unexamined within the field and literature of global education.…

  15. Population momentum across the demographic transition.

    PubMed

    Blue, Laura; Espenshade, Thomas J

    2011-01-01

    Population momentum is the main driver of global population growth today, and this makes an appreciation of momentum critical to understanding contemporary worldwide growth dynamics. This article traces population momentum along with two recently defined measures of momentum decomposed—stable and nonstable momentum—across the demographic transition. We use historical data and population projections from 16 countries to illustrate some previously ignored empirical regularities of the demographic transition in both the developed and the developing world. We also demonstrate the dynamic nature of stable and nonstable momentum, as changes in stable momentum lead to predictable changes in current and future nonstable momentum. These results suggest that momentum, which by definition is measured at a point in time, can also be considered as a process that unfolds over time.

  16. Kuramoto-type phase transition with metronomes

    NASA Astrophysics Data System (ADS)

    Boda, Sz; Ujvári, Sz; Tunyagi, A.; Néda, Z.

    2013-11-01

    Metronomes placed on the perimeter of a disc-shaped platform, which can freely rotate in a horizontal plane, are used for a simple classroom illustration of the Kuramoto-type phase transition. The rotating platform induces a global coupling between the metronomes, and the strength of this coupling can be varied by tilting the metronomes’ swinging plane relative to the radial direction on the disc. As a function of the tilting angle, a transition from spontaneously synchronized to unsynchronized states is observable. By varying the number of metronomes on the disc, finite-size effects are also exemplified. A realistic theoretical model is introduced and used to reproduce the observed results. Computer simulations of this model allow a detailed investigation of the emerging collective behaviour in this system.

  17. The Concept of Transition System

    ERIC Educational Resources Information Center

    Raffe, David

    2008-01-01

    The term "transition system" describes features of a country's institutional arrangements which shape young people's education-work transitions. It explains why national differences in transition processes and outcomes persist despite apparent pressures for convergence. This paper asks how the concept of transition system has been…

  18. Ethics in global surgery.

    PubMed

    Wall, Anji E

    2014-07-01

    Global surgery, while historically a small niche, is becoming a larger part of the global health enterprise. This article discusses the burden of global surgery, emphasizing the importance of addressing surgical needs in low- and middle-income countries. It describes the barriers to surgical care in the developing world, the ethical challenges that these barriers create, and strategies to overcome these barriers. It emphasizes the crucial role of preparation for global surgical interventions as a way to maximize benefits as well as minimize harms and ethical challenges. It ends with the cautionary statement that preparation does not eliminate ethical problems, so surgical volunteers must be prepared not only for the technical challenges of global surgery but also for the ethical challenges.

  19. Globalization of healthcare.

    PubMed

    2012-05-01

    Globalization-the increasing transnational circulation of money, goods, people, ideas, and information worldwide-is generally recognized as one of the most powerful forces shaping our current and future history. How is it affecting healthcare, and in that context, what is the purpose and significance of Global Advances in Health and Medicine (GAHM), publisher of this journal? Our goal is not homogenization but rather to provide an opportunity for integration, convergence, and collaboration across cultures. By respecting and conserving the richness and diversity of each new medicine, we embrace globalization. Globalization is of course not new; it began in the Renaissance and particularly with the 15th- and 16th-century voyages of exploration by Columbus, Magellan, and others. Since the beginning of time, there have been interactions and exchanges among different peoples and cultures. However, the current magnitude of globalization is unprecedented and yet still expanding rapidly.

  20. Global Value Trees

    PubMed Central

    Zhu, Zhen; Puliga, Michelangelo; Cerina, Federica; Chessa, Alessandro; Riccaboni, Massimo

    2015-01-01

    The fragmentation of production across countries has become an important feature of the globalization in recent decades and is often conceptualized by the term “global value chains” (GVCs). When empirically investigating the GVCs, previous studies are mainly interested in knowing how global the GVCs are rather than how the GVCs look like. From a complex networks perspective, we use the World Input-Output Database (WIOD) to study the evolution of the global production system. We find that the industry-level GVCs are indeed not chain-like but are better characterized by the tree topology. Hence, we compute the global value trees (GVTs) for all the industries available in the WIOD. Moreover, we compute an industry importance measure based on the GVTs and compare it with other network centrality measures. Finally, we discuss some future applications of the GVTs. PMID:25978067

  1. Globalization and Health.

    PubMed

    Martin, Greg

    2005-04-22

    This debut editorial of Globalization and Health introduces the journal, briefly delineating its goals and objectives and outlines its scope of subject matter. 'Open Access' publishing is expected to become an increasingly important format for peer reviewed academic journals and that Globalization and Health is 'Open Access' is appropriate. The rationale behind starting a journal dedicated to globalization and health is three fold:Firstly: Globalization is reshaping the social geography within which we might strive to create health or prevent disease. The determinants of health - be they a SARS virus or a predilection for fatty foods - have joined us in our global mobility. Driven by economic liberalization and changing technologies, the phenomenon of 'access' is likely to dominate to an increasing extent the unfolding experience of human disease and wellbeing.Secondly: Understanding globalization as a subject matter itself needs certain benchmarks and barometers of its successes and failings. Health is one such barometer. It is a marker of social infrastructure and social welfare and as such can be used to either sound an alarm or give a victory cheer as our interconnectedness hurts and heals the populations we serve.And lastly: In as much as globalization can have an effect on health, it is also true that health and disease has an effect on globalization as exemplified by the existence of quarantine laws and the devastating economic effects of the AIDS pandemic.A balanced view would propose that the effects of globalization on health (and health systems) are neither universally good nor bad, but rather context specific. If the dialogue pertaining to globalization is to be directed or biased in any direction, then it must be this: that we consider the poor first.

  2. Quantum interface unbinding transitions

    NASA Astrophysics Data System (ADS)

    Jakubczyk, P.

    2012-08-01

    We consider interfacial phenomena accompanying bulk quantum phase transitions in the presence of surface fields. On general grounds we argue that the surface contribution to the system free energy involves a line of singularities characteristic of an interfacial phase transition, occurring below the bulk transition temperature Tc down to T=0. This implies the occurrence of an interfacial quantum critical regime extending into finite temperatures and located within the portion of the phase diagram where the bulk is ordered. Even in situations where the bulk order sets in discontinuously at T=0, the system's behavior at the boundary may be controlled by a divergent length scale if the tricritical temperature is sufficiently low. Relying on an effective interfacial model we compute the surface phase diagram in bulk spatial dimensionality d⩾2 and extract the values of the exponents describing the interfacial singularities in d⩾3.

  3. Global Collaborations - Prospects and Problems

    NASA Astrophysics Data System (ADS)

    Corbett, Ian

    2005-04-01

    International collaboration has long been a feature of science. Collaborative investments in joint facilities and projects have grown considerably over the past 20-40 years, and many projects have been multinational from the start. This has been particularly true in Europe, where intergovernmental organizations such as CERN, ESA, and ESO have enabled European countries to carry out forefront science with state-of-art facilites which would have been beyond the capabilities of any one country. A brief survey of these organizations, their structure, and the possible reasons behind their success is given. The transition from regional to global creates new problems. Global scale projects face a range of generic issues which must be addressed and overcome if the project is to be a success. Each project has its own specific boundary conditions and each adopts an approach best fitted to its own objectives and constraints. Experience with billion dollar projects such as the SSC, LHC, and ITER shows the key problem areas and demonstrates the importance of preparatory work in the early stages to settle issues such as schedule, funding, location, legal and managerial structure, and oversight. A range of current and proposed intercontinental or global projects - so- called ``Megascience Projects" - is reviewed. Such projects, originally a feature of space and particle physics, are now becoming more common, and very large projects in astronomy, for example ALMA and 50 - 100m telescopes, and other areas of physics now fall into the `global' category. These projects are on such a large scale, from any scientific, managerial, financial or political perspective, and have such global importance, that they have necessarily been conceived as international from the outset. Increasing financial pressures on governments and funding agencies in the developed countries place additional demands on the project planning. The contrasting approaches, problems faced, and progress made in various

  4. Electroweak phase transitions

    SciTech Connect

    Anderson, G.W.

    1991-09-16

    An analytic treatment of the one Higgs doublet, electroweak phase transition is given. The phase transition is first order, occurs by the nucleation of thin walled bubbles and completes at a temperature where the order parameter, {l_angle}{phi}{r_angle}{sub T} is significantly smaller than it is when the origin becomes absolutely unstable. The rate of anomalous baryon number violation is an exponentially function of {l_angle}{phi}{r_angle}{sub T}. In very minimal extensions of the standard model it is quite easy to increase {l_angle}{phi}{r_angle}{sub T} so that anomalous baryon number violation is suppressed after completion of the phase transition. Hence baryogenesis at the electroweak phase transition is tenable in minimal of the standard model. In some cases additional phase transitions are possible. For a light Higgs boson, when the top quark mass is sufficiently large, the state where the Higgs field has a vacuum expectation value {l_angle}{phi}{r_angle} = 246 GeV is not the true minimum of the Higgs potential. When this is the case, and when the top quark mass exceeds some critical value, thermal fluctuations in the early universe would have rendered the state {l_angle}{phi}{r_angle} = 246 GeV unstable. The requirement that the state {l_angle}{phi}{r_angle} = 246 GeV is sufficiently long lived constrains the masses of the Higgs boson and the top quark. Finally, we consider whether local phase transitions can be induced by heavy particles which act as seeds for deformations in the scalar field.

  5. Electroweak phase transitions

    SciTech Connect

    Anderson, G.W.

    1991-09-16

    An analytic treatment of the one Higgs doublet, electroweak phase transition is given. The phase transition is first order, occurs by the nucleation of thin walled bubbles and completes at a temperature where the order parameter, {l angle}{phi}{r angle}{sub T} is significantly smaller than it is when the origin becomes absolutely unstable. The rate of anomalous baryon number violation is an exponentially function of {l angle}{phi}{r angle}{sub T}. In very minimal extensions of the standard model it is quite easy to increase {l angle}{phi}{r angle}{sub T} so that anomalous baryon number violation is suppressed after completion of the phase transition. Hence baryogenesis at the electroweak phase transition is tenable in minimal of the standard model. In some cases additional phase transitions are possible. For a light Higgs boson, when the top quark mass is sufficiently large, the state where the Higgs field has a vacuum expectation value {l angle}{phi}{r angle} = 246 GeV is not the true minimum of the Higgs potential. When this is the case, and when the top quark mass exceeds some critical value, thermal fluctuations in the early universe would have rendered the state {l angle}{phi}{r angle} = 246 GeV unstable. The requirement that the state {l angle}{phi}{r angle} = 246 GeV is sufficiently long lived constrains the masses of the Higgs boson and the top quark. Finally, we consider whether local phase transitions can be induced by heavy particles which act as seeds for deformations in the scalar field.

  6. Trends in global earthquake loss

    NASA Astrophysics Data System (ADS)

    Arnst, Isabel; Wenzel, Friedemann; Daniell, James

    2016-04-01

    Based on the CATDAT damage and loss database we analyse global trends of earthquake losses (in current values) and fatalities for the period between 1900 and 2015 from a statistical perspective. For this time period the data are complete for magnitudes above 6. First, we study the basic statistics of losses and find that losses below 10 bl. US satisfy approximately a power law with an exponent of 1.7 for the cumulative distribution. Higher loss values are modelled with the General Pareto Distribution (GPD). The 'transition' between power law and GPD is determined with the Mean Excess Function. We split the data set into a period of pre 1955 and post 1955 loss data as in those periods the exposure is significantly different due to population growth. The Annual Average Loss (AAL) for direct damage for events below 10 bl. US differs by a factor of 6, whereas the incorporation of the extreme loss events increases the AAL from 25 bl. US/yr to 30 bl. US/yr. Annual Average Deaths (AAD) show little (30%) difference for events below 6.000 fatalities and AAD values of 19.000 and 26.000 deaths per year if extreme values are incorporated. With data on the global Gross Domestic Product (GDP) that reflects the annual expenditures (consumption, investment, government spending) and on capital stock we relate losses to the economic capacity of societies and find that GDP (in real terms) grows much faster than losses so that the latter one play a decreasing role given the growing prosperity of mankind. This reasoning does not necessarily apply on a regional scale. Main conclusions of the analysis are that (a) a correct projection of historic loss values to nowadays US values is critical; (b) extreme value analysis is mandatory; (c) growing exposure is reflected in the AAL and AAD results for the periods pre and post 1955 events; (d) scaling loss values with global GDP data indicates that the relative size - from a global perspective - of losses decreases rapidly over time.

  7. Global Symmetries, Volume Independence, and Continuity in Quantum Field Theories.

    PubMed

    Sulejmanpasic, Tin

    2017-01-06

    We discuss quantum field theories with global SU(N) and O(N) symmetries for which temporal direction is compactified on a circle of size L with periodicity of fields up to a global symmetry transformation, i.e., twisted boundary conditions. Such boundary conditions correspond to an insertion of the global symmetry operator in the partition function. We argue in general and prove in particular for CP(N-1) and O(N) nonlinear sigma models that large-N volume independence holds. Further we show that the CP(N-1) theory is free from the Affleck phase transition confirming the Ünsal-Dunne continuity conjecture.

  8. UTM: Universal Transit Modeller

    NASA Astrophysics Data System (ADS)

    Deeg, Hans J.

    2014-12-01

    The Universal Transit Modeller (UTM) is a light-curve simulator for all kinds of transiting or eclipsing configurations between arbitrary numbers of several types of objects, which may be stars, planets, planetary moons, and planetary rings. A separate fitting program, UFIT (Universal Fitter) is part of the UTM distribution and may be used to derive best fits to light-curves for any set of continuously variable parameters. UTM/UFIT is written in IDL code and its source is released in the public domain under the GNU General Public License.

  9. Identity, Family, and Faith: U.S. Third Culture Kids Transition to College

    ERIC Educational Resources Information Center

    Kortegast, Carrie; Yount, Emily M.

    2016-01-01

    Recent trends in globalization have increased the number of U.S. children and adolescents being raised outside the United States. Using the framework of adults in transition, the authors sought to understand the structure of Third Culture Kids' (TCKs), specifically Missionary Kids', transition to college. Findings indicate that participants must…

  10. Control of atomic transition rates via laser-light shaping

    NASA Astrophysics Data System (ADS)

    Jáuregui, R.

    2015-04-01

    A modular systematic analysis of the feasibility of modifying atomic transition rates by tailoring the electromagnetic field of an external coherent light source is presented. The formalism considers both the center of mass and internal degrees of freedom of the atom, and all properties of the field: frequency, angular spectrum, and polarization. General features of recoil effects for internal forbidden transitions are discussed. A comparative analysis of different structured light sources is explicitly worked out. It includes spherical waves, Gaussian beams, Laguerre-Gaussian beams, and propagation invariant beams with closed analytical expressions. It is shown that increments in the order of magnitude of the transition rates for Gaussian and Laguerre-Gaussian beams, with respect to those obtained in the paraxial limit, require waists of the order of the wavelength, while propagation invariant modes may considerably enhance transition rates under more favorable conditions. For transitions that can be naturally described as modifications of the atomic angular momentum, this enhancement is maximal (within propagation invariant beams) for Bessel modes, Mathieu modes can be used to entangle the internal and center-of-mass involved states, and Weber beams suppress this kind of transition unless they have a significant component of odd modes. However, if a recoil effect of the transition with an adequate symmetry is allowed, the global transition rate (center of mass and internal motion) can also be enhanced using Weber modes. The global analysis presented reinforces the idea that a better control of the transitions between internal atomic states requires both a proper control of the available states of the atomic center of mass, and shaping of the background electromagnetic field.

  11. Global Partnership in Global Earth Observations

    NASA Astrophysics Data System (ADS)

    Smirnov, A.; Obersteiner, M.

    2007-12-01

    The emergence of a global partnership on earth observations will crucially drive the configuration of future observing systems and consequently shape how socio-economic benefits are generated. In this paper we take a game-theoretical approach to model cooperation on building global earth observation systems. We consider several societies whose economies are subject to shocks mimicking major natural disasters. Economies operate optimally and lead to the best possible expected value for the social welfares in the future. In order to increase its welfare even more society can make a decision to invest into a global alerting system which lowers the risk of disasters. We start our investigation from a single-society case and show conditions under which benefits of such investment can be reaped. The propensity to invest increases with economic affluence and degree of vulnerability to natural disasters. We find that for poor and/or less vulnerable countries it is better to forbear from investment. If to consider a situation of multiple societies a strategic gaming situation emerges motivated by the fact that every society will benefit from a global system regardless of whether they invested or not. Our analysis of possible equilibrium solutions shows that similar to the formation of trading blocks (e.g. EU, NAFTA) only in the case of similar societies we will observe cooperation behavior (when all invest) and otherwise we will observe free-riding. This insight, that we might face a prisoners dilemma problem in the formation of a GEOSS, has important implications for the GEO process.

  12. How global brands compete.

    PubMed

    Holt, Douglas B; Quelch, John A; Taylor, Earl L

    2004-09-01

    It's time to rethink global branding. More than two decades ago, Harvard Business School professor Theodore Levitt argued that corporations should grow by selling standardized products all over the world. But consumers in most countries had trouble relating to generic products, so executives instead strove for global scale on backstage activities such as production while customizing product features and selling techniques to local tastes. Such "glocal" strategies now rule marketing. Global branding has lost more luster recently because transnational companies have been under siege, with brands like Coca-Cola and Nike becoming lightning rods for antiglobalization protests. The instinctive reaction of most transnational companies has been to try to fly below the radar. But global brands can't escape notice. In fact, most transnational corporations don't realize that because of their power and pervasiveness, people view them differently than they do other firms. In a research project involving 3,300 consumers in 41 countries, the authors found that most people choose one global brand over another because of differences in the brands'global qualities. Ratherthan ignore the global characteristics of their brands, firms must learn to manage those characteristics. That's critical, because future growth for most companies will likely come from foreign markets. Consumers base preferences on three dimensions of global brands--quality (signaled by a company's global stature); the cultural myths that brands author; and firms' efforts to address social problems. The authors also found that it didn't matter to consumers whether the brands they bought were American--a remarkable finding considering that the study was conducted when anti-American sentiment in many nations was on the rise.

  13. Music: Creativity and Structure Transitions

    NASA Astrophysics Data System (ADS)

    Pietrocini, Emanuela

    Music, compared to other complex forms of representation, is fundamentally characterized by constant evolution and a dynamic succession of structure reference models. This is without taking into account historical perspective, the analysis of forms and styles, or questions of a semantic nature; the observation rather refers to the phenomenology of the music system. The more abstract a compositional model, the greater the number and frequency of variables that are not assimilated to the reference structure; this "interference" which happens more often than not in an apparently casual manner, modifies the creative process to varying but always substantial degrees: locally, it produces a disturbance in perceptive, formal and structural parameters, resulting more often than not in a synaesthetic experience; globally, on the other hand, it defines the terms of a transition to a new state, in which the relations between elements and components modify the behavior of the entire system from which they originated. It is possible to find examples of this phenomenon in the whole range of musical production, in particular in improvisations, in the use of the Basso Continuo, and in some contrapuntal works of the baroque period, music whose temporal dimension can depart from the limits of mensurability and symmetry to define an open compositional environment in continuous evolution.

  14. The Global Enery and Water Cycle Experiment Science Strategy

    NASA Technical Reports Server (NTRS)

    Chahine, M. T.

    1997-01-01

    The distribution of water in the atmosphere and at the surface of the Earth is the most influential factor regulating our environment, not only because water is essential for life but also because through phase transitions it is the main energy source that control clouds and radiation and drives the global circulation of the atmosphere.

  15. Global atmospheric changes.

    PubMed Central

    Piver, W T

    1991-01-01

    Increasing concentrations of CO2 and other greenhouse gases in the atmosphere can be directly related to global warming. In terms of human health, because a major cause of increasing atmospheric concentrations of CO2 is the increased combustion of fossil fuels, global warming also may result in increases in air pollutants, acid deposition, and exposure to ultraviolet (UV) radiation. To understand better the impacts of global warming phenomena on human health, this review emphasizes the processes that are responsible for the greenhouse effect, air pollution, acid deposition, and increased exposure to UV radiation. PMID:1820255

  16. Variational transition state theory

    SciTech Connect

    Truhlar, D.G.

    1993-12-01

    This research program involves the development of variational transition state theory (VTST) and semiclassical tunneling methods for the calculation of gas-phase reaction rates and selected applications. The applications are selected for their fundamental interest and/or their relevance to combustion.

  17. Youth Policy in Transition.

    ERIC Educational Resources Information Center

    Timpane, Michael; And Others

    A study team was commissioned to critically review three independent reports on youth and schooling: "Youth: Transition to Adulthood"; "The Education of Adolescents"; and "The Reform of Secondary Education." The study team examined the reports in light of the most recent available social science evidence. The three reports, presenting similar…

  18. Singing Smoothes Classroom Transitions

    ERIC Educational Resources Information Center

    Mathews, Sarah E.

    2012-01-01

    Just as humming a merry tune helped Snow White and her furry animal friends to quickly clean a filthy cottage in the movie "Snow White and the Seven Dwarfs" (Disney & Cottrell, 1937), singing can be an effective way to help keep young children fully engaged during classroom transitions. The purposes of this article are to: (1) consider why…

  19. A Transiting Jupiter Analog

    NASA Astrophysics Data System (ADS)

    Kipping, D. M.; Torres, G.; Henze, C.; Teachey, A.; Isaacson, H.; Petigura, E.; Marcy, G. W.; Buchhave, L. A.; Chen, J.; Bryson, S. T.; Sandford, E.

    2016-04-01

    Decadal-long radial velocity surveys have recently started to discover analogs to the most influential planet of our solar system, Jupiter. Detecting and characterizing these worlds is expected to shape our understanding of our uniqueness in the cosmos. Despite the great successes of recent transit surveys, Jupiter analogs represent a terra incognita, owing to the strong intrinsic bias of this method against long orbital periods. We here report on the first validated transiting Jupiter analog, Kepler-167e (KOI-490.02), discovered using Kepler archival photometry orbiting the K4-dwarf KIC-3239945. With a radius of (0.91+/- 0.02) {R}{{J}}, a low orbital eccentricity ({0.06}-0.04+0.10), and an equilibrium temperature of (131+/- 3) K, Kepler-167e bears many of the basic hallmarks of Jupiter. Kepler-167e is accompanied by three Super-Earths on compact orbits, which we also validate, leaving a large cavity of transiting worlds around the habitable-zone. With two transits and continuous photometric coverage, we are able to uniquely and precisely measure the orbital period of this post snow-line planet (1071.2323 ± 0.0006d), paving the way for follow-up of this K = 11.8 mag target.

  20. String mediated phase transitions

    NASA Technical Reports Server (NTRS)

    Copeland, ED; Haws, D.; Rivers, R.; Holbraad, S.

    1988-01-01

    It is demonstrated from first principles how the existence of string-like structures can cause a system to undergo a phase transition. In particular, the role of topologically stable cosmic string in the restoration of spontaneously broken symmetries is emphasized. How the thermodynamic properties of strings alter when stiffness and nearest neighbor string-string interactions are included is discussed.

  1. exorings: Exoring Transit Properties

    NASA Astrophysics Data System (ADS)

    Zuluaga, Jorge I.; Kipping, David M.; Sucerquia, Mario; Alvarado, Jaime A.

    2017-03-01

    Exorings is suitable for surveying entire catalogs of transiting planet candidates for exoring candidates, providing a subset of objects worthy of more detailed light curve analysis. Moreover, it is highly suited for uncovering evidence of a population of ringed planets by comparing the radius anomaly and PR-effects in ensemble studies.

  2. A Survey Transition Course

    ERIC Educational Resources Information Center

    Johnston, William; McAllister, Alex M.

    2012-01-01

    Successful outcomes for a "Transition Course in Mathematics" have resulted from two unique design features. The first is to run the course as a "survey course" in mathematics, introducing sophomore-level students to a broad set of mathematical fields. In this single mathematics course, undergraduates benefit from an introduction of proof…

  3. Tips for Transition

    ERIC Educational Resources Information Center

    Kellems, Ryan O.; Morningstar, Mary E.

    2010-01-01

    The Individuals With Disabilities Education Improvement Act of 2004 (IDEA) states that transition planning should begin at the earliest age appropriate and no later than age 16. IDEA requires schools to make collaborative efforts to provide students access to an array of postschool activities including integrated employment, postsecondary…

  4. Families in Transition.

    ERIC Educational Resources Information Center

    Britton, Patti O., Ed.; McGee, Michael, Ed.

    1987-01-01

    This issue of "Emphasis" deals with families in transition, providing some model programs for the new family and some historical perspectives on how families have developed over time. Articles include: (1) "Nostalgia on the Right" (Nancy Theriot); (2) "Heart to Heart" (Nancy Harrington-MacLennan); (3) "The Media Get the Message" (Janet Alyn); (4)…

  5. The TRANSITION Program.

    ERIC Educational Resources Information Center

    Office of the Assistant Secretary of Defense for Manpower and Reserve Affairs (DOD), Washington, DC.

    Operated on a voluntary, decentralized basis at 215 military bases (58 overseas), the TRANSITION Program is designed to provide maximum guidance and training or educational opportunities for servicemen during their last six months of duty to prepare them for productive reentry into civilian life. Public and private placement services are also…

  6. Selected Readings in Transition.

    ERIC Educational Resources Information Center

    Harnisch, Delwyn L.; And Others

    This collection of readings covers critical issues related to transition of youth with disabilities from school to post-school experiences. The first paper, titled "'Cognitive Return' of Schooling for Students with Disabilities: Preliminary Findings from 'High School and Beyond'" by Delwyn L. Harnisch and Ian A. G. Wilkinson, applies…

  7. Learning for Life Transitions

    ERIC Educational Resources Information Center

    Varmecky, Jane Hyde

    2012-01-01

    Many adults return to formal learning situations to pursue lifelong learning goals because their lives are in transition from dealing with real-life problems such as divorce and re-marriage. The purpose of this study was to describe what couples learned that contributed to the success of their subsequent marriages and how they learned it. The…

  8. Modeling of transitional flows

    NASA Technical Reports Server (NTRS)

    Lund, Thomas S.

    1988-01-01

    An effort directed at developing improved transitional models was initiated. The focus of this work was concentrated on the critical assessment of a popular existing transitional model developed by McDonald and Fish in 1972. The objective of this effort was to identify the shortcomings of the McDonald-Fish model and to use the insights gained to suggest modifications or alterations of the basic model. In order to evaluate the transitional model, a compressible boundary layer code was required. Accordingly, a two-dimensional compressible boundary layer code was developed. The program was based on a three-point fully implicit finite difference algorithm where the equations were solved in an uncoupled manner with second order extrapolation used to evaluate the non-linear coefficients. Iteration was offered as an option if the extrapolation error could not be tolerated. The differencing scheme was arranged to be second order in both spatial directions on an arbitrarily stretched mesh. A variety of boundary condition options were implemented including specification of an external pressure gradient, specification of a wall temperature distribution, and specification of an external temperature distribution. Overall the results of the initial phase of this work indicate that the McDonald-Fish model does a poor job at predicting the details of the turbulent flow structure during the transition region.

  9. Families in Transition .

    ERIC Educational Resources Information Center

    Bundy, Michael L., Ed.; Gumaer, James, Ed.

    1984-01-01

    Focuses on disrupted families and the role of the school counselor in helping children adjust. Describes characteristics of healthy families, and discusses the transition to the blended family, effects of divorce groups on children's classroom behavior, counseling children in stepfamilies, single-parent families, and parenting strengths of single…

  10. Immigration and Adult Transitions

    ERIC Educational Resources Information Center

    Rumbaut, Ruben G.; Komaie, Golnaz

    2010-01-01

    Almost 30 percent of the more than 68 million young adults aged eighteen to thirty-four in the United States today are either foreign born or of foreign parentage. As these newcomers make their transitions to adulthood, say Ruben Rumbaut and Golnaz Komaie, they differ significantly not only from one another but also from their native-parentage…

  11. Nursing Role Transition Preceptorship

    ERIC Educational Resources Information Center

    Batory, Susan M.

    2014-01-01

    The preceptorship clinical experience in a practical nursing (PN) program at a Midwestern community college is considered crucial to the PN students' transition from novice nurse to professional nurse. However, no research has been available to determine whether the preceptorship clinical accomplishes its purpose. A case study was conducted to…

  12. Administrative Theory in Transition.

    ERIC Educational Resources Information Center

    Griffiths, Daniel E.

    This monograph analyzes transition in educational administrative theory. A brief introductory section describes the theoretical movement, the substance and repercussions of Thomas Greenfield's critique of educational administrative theory in 1974, and emerging qualitative approaches. Seven readings, all written by the volume's author, view…

  13. Transition at hypersonic speeds

    NASA Technical Reports Server (NTRS)

    Morkovin, Mark V.

    1987-01-01

    Certain conjectures on the physics of instabilities in high-speed flows are discussed and the state of knowledge of hypersonic transition summarized. The case is made for an unpressured systematic research program in this area consisting of controlled microscopic experiments, theory, and numerical simulations.

  14. Conformational dynamics of the SH1-SH2 helix in the transition states of myosin subfragment-1.

    PubMed Central

    Nitao, Lisa K; Yeates, Todd O; Reisler, Emil

    2002-01-01

    The alpha-helix containing the thiols, SH1 (Cys-707) and SH2 (Cys-697), has been proposed to be one of the structural elements responsible for the transduction of conformational changes in the myosin head (subfragment-1 (S1)). Previous studies, using a method that isolated and measured the rate of the SH1-SH2 cross-linking step, showed that this helix undergoes ligand-induced conformational changes. However, because of long incubation times required for the formation of the transition state complexes (S1.ADP.BeF(x), S1.ADP.AlF(4)-, and S1.ADP.V(i)), this method could not be used to determine the cross-linking rate constants for such states. In this study, kinetic data from the SH1-SH2 cross-linking reaction were analyzed by computational methods to extract rate constants for the two-step mechanism. For S1.ADP.BeF(x), the results obtained were similar to those for S1.ATPgammaS. For reactions involving S1.ADP.AlF(4)- and S1.ADP.V(i), the first step (SH1 modification) is rate limiting; consequently, only lower limits could be established for the rate constants of the cross-linking step. Nevertheless, these results show that the cross-linking rate constants in the transition state complexes are increased at least 20-fold for all the reagents, including the shortest one, compared with nucleotide-free S1. Thus, the SH1-SH2 helix appears to be destabilized in the post-hydrolysis state. PMID:12414706

  15. Transit of Extrasolar Planets

    NASA Technical Reports Server (NTRS)

    Doyle, Laurance R.

    1998-01-01

    During the past five years we have pursued the detection of extrasolar planets by the photometric transit method, i.e. the detection of a planet by watching for a drop in the brightness of the light as it crosses in front of a star. The planetary orbit must cross the line-of-sight and so most systems will not be lined up for such a transit to ever occur. However, we have looked at eclipsing binary systems which are already edge-on. Such systems must be very small in size as this makes the differential light change due to a transit much greater for a given planet size (the brightness difference will be proportional to the area of the transiting planet to the disc area of the star). Also, the planet forming region should be closer to the star as small stars are generally less luminous (that is, if the same thermal regime for planet formation applies as in the solar system). This led to studies of the habitable zone around other stars, as well. Finally, we discovered that our data could be used to detect giant planets without transits as we had been carefully timing the eclipses of the stars (using a GPS antenna for time) and this will drift by being offset by any giant planets orbiting around the system, as well. The best summary of our work may be to just summarize the 21 refereed papers produced during the time of this grant. This will be done is chronological order and in each section separately.

  16. Quantum Transition State Theory

    NASA Astrophysics Data System (ADS)

    Waalkens, Holger

    2009-03-01

    The main idea of Wigner's transition state theory (TST) is to compute reaction rates from the flux through a dividing surface placed between reactants and products. In order not to overestimate the rate the dividing surface needs to have the no- recrossing property, i.e. reactive trajectories cross the dividing surface exactly once, and nonreactive trajectories do not cross it at all. The long standing problem of how to construct such a diving surface for multi-degree-of-freedom systems was solved only recently using ideas from dynamical systems theory. Here a normal form allows for a local decoupling of the classical dynamics which leads to the explicit construction of the phase space structures that govern the reaction dynamics through transition states. The dividing surface is spanned by a normally hyperbolic manifold which is the mathematical manifestation of the transition state as an unstable invariant subsystem of one degree of freedom less than the full system. The mere existence of a quantum version of TST is discussed controversially in the literature. The key isssue is the presence of quantum mechanical tunneling which prohibits the existence of a local theory analogous to the classical case. Various approaches have been devloped to overcome this problem by propagating quantum wavefunctions through the transition state region. These approaches have in common that they are computationally very expensive which seriously limits their applicability. In contrast the approach by Roman Schubert, Stephen Wiggins and myself is local in nature. A quantum normal form allows us to locally decouple the quantum dynamics to any desired order in Planck's constant. This yields not only the location of the scattering and resonance wavefunctions relative to the classical phase space structures, but also leads to very efficient algorithms to compute cumulative reaction probabilities and Gamov-Siegert resonances which are the quantum imprints of the transition state.

  17. Global Precipitation Measurement Mission Launch and Commissioning

    NASA Technical Reports Server (NTRS)

    Davis, Nikesha; Deweese, Keith; Vess, Missie; Welter, Gary; O'Donnell, James R., Jr.

    2015-01-01

    During launch and early operation of the Global Precipitation Measurement (GPM) Mission, the Guidance, Navigation and Control (GNC) analysis team encountered four main on orbit anomalies. These include: (1) unexpected shock from Solar Array deployment, (2) momentum buildup from the Magnetic Torquer Bars (MTBs) phasing errors, (3) transition into Safehold due to albedo-induced Course Sun Sensor (CSS) anomaly, and (4) a flight software error that could cause a Safehold transition due to a Star Tracker occultation. This paper will discuss ways GNC engineers identified and tracked down the root causes. Flight data and GNC on board models will be shown to illustrate how each of these anomalies were investigated and mitigated before causing any harm to the spacecraft. On May 29, 2014, GPM was handed over to the Mission Flight Operations Team after a successful commissioning period. Currently, GPM is operating nominally on orbit, collecting meaningful scientific data that will significantly improve our understanding of the Earth's climate and water cycle.

  18. Global reach and engagement

    NASA Astrophysics Data System (ADS)

    2016-09-01

    Popular culture reflects both the interests of and the issues affecting the general public. As concerns regarding climate change and its impacts grow, is it permeating into popular culture and reaching that global audience?

  19. The Global Menace

    PubMed Central

    Hodges, Sarah

    2015-01-01

    Summary The history of medicine has gone ‘global.’ Why? Can the proliferation of the ‘global’ in our writing be explained away as a product of staying true to our historical subjects’ categories? Or has this historiography in fact delivered a new ‘global’ problematic or performed serious ‘global’ analytic work? The situation is far from clear, and it is the tension between the global as descriptor and an analytics of the global that concerns me here. I have three main concerns: (1) that there is an epistemic collusion between the discourses of universality that inform medical science and global-talk; (2) that the embrace of the ‘global’ authorises a turning away from analyses of power in history-writing in that (3) this turning away from analyses of power in history-writing leads to scholarship that reproduces rather than critiques globalisation as a set of institutions, discourses and practices. PMID:26345469

  20. Cancer and globalization.

    PubMed

    Sasco, Annie J

    2008-02-01

    Global human cancer is increasing. Exposures to cancer risk factors are not only becoming more prevalent in the less industrialized countries, but they have also become more complex all over the world. Human societies have always traded and migrated, yet the growth of powerful economic institutions and globalization is accelerating, mixing many cancer risk factors. Critically, new cancer risk factors have also appeared, concurrent with globalization: modern diet, addictive products, pharmaceuticals, and toxic and waste products. Prevention, which still rests on recognition and elimination of exposure to carcinogens, is difficult, with seemingly opposed priorities such as income (corporate or individual) versus health. The solutions require not only individual behavioural change but also more importantly innovative action of all concerned at the global, collective level.

  1. Global Health Observatory (GHO)

    MedlinePlus

    ... mental health Noncommunicable diseases Mental health 3.5 Substance abuse Global Information System on Alcohol and Health (GISAH) Resources for the Prevention and Treatment of Substance Use Disorders 3.6 Road traffic injuries Road ...

  2. Meeting global conservation challenges

    NASA Astrophysics Data System (ADS)

    2016-10-01

    Hot on the heels of last year's Sustainable Development Goals and the Paris Agreement, representatives from the global conservation community met to set the conservation agenda that will help to implement these targets.

  3. Technology and Global Change

    NASA Astrophysics Data System (ADS)

    Grübler, Arnulf

    2003-10-01

    Technology and Global Change describes how technology has shaped society and the environment over the last 200 years. Technology has led us from the farm to the factory to the internet, and its impacts are now global. Technology has eliminated many problems, but has added many others (ranging from urban smog to the ozone hole to global warming). This book is the first to give a comprehensive description of the causes and impacts of technological change and how they relate to global environmental change. Written for specialists and nonspecialists alike, it will be useful for researchers and professors, as a textbook for graduate students, for people engaged in long-term policy planning in industry (strategic planning departments) and government (R & D and technology ministries, environment ministries), for environmental activists (NGOs), and for the wider public interested in history, technology, or environmental issues.

  4. Transition States and transition state analogue interactions with enzymes.

    PubMed

    Schramm, Vern L

    2015-04-21

    Enzymatic transition states have lifetimes of a few femtoseconds (fs). Computational analysis of enzyme motions leading to transition state formation suggests that local catalytic site motions on the fs time scale provide the mechanism to locate transition states. An experimental test of protein fs motion and its relation to transition state formation can be provided by isotopically heavy proteins. Heavy enzymes have predictable mass-altered bond vibration states without altered electrostatic properties, according to the Born-Oppenheimer approximation. On-enzyme chemistry is slowed in most heavy proteins, consistent with altered protein bond frequencies slowing the search for the transition state. In other heavy enzymes, structural changes involved in reactant binding and release are also influenced. Slow protein motions associated with substrate binding and catalytic site preorganization are essential to allow the subsequent fs motions to locate the transition state and to facilitate the efficient release of products. In the catalytically competent geometry, local groups move in stochastic atomic motion on the fs time scale, within transition state-accessible conformations created by slower protein motions. The fs time scale for the transition state motions does not permit thermodynamic equilibrium between the transition state and stable enzyme states. Isotopically heavy enzymes provide a diagnostic tool for fast coupled protein motions to transition state formation and mass-dependent conformational changes. The binding of transition state analogue inhibitors is the opposite in catalytic time scale to formation of the transition state but is related by similar geometries of the enzyme-transition state and enzyme-inhibitor interactions. While enzymatic transition states have lifetimes as short as 10(-15) s, transition state analogues can bind tightly to enzymes with release rates greater than 10(3) s. Tight-binding transition state analogues stabilize the rare but

  5. Turbulent Convection in ADAF-SSD Transitions

    NASA Astrophysics Data System (ADS)

    Gracia, J.; Camenzind, M.

    The cold Shakura & Sunyaev disk (SSD) has proven very successful in describing spectra of acctretion flows onto stellar objects like white dwarfs. But discrepancies arise if one tries to model accretion onto stellar black holes or even AGN. These objects feature an additional hot, hart component which cannot be accounted for even including the transonic nature of the flow. It is clear that cold disk and hot gas must co-exist in a small volume. One possible model is the transition from an outer cold SSD to an inner hot advection dominated accretion flow (ADAF). We investigate such models using time-dependent 1D height integrated Euler equations including detailed energy transport mechanisms like turbulent convection and an additional radiative transfer equation. We find global self-consistent solution with ADAF-SSD transitions. We confirm the expected behaviour away from the transition region. While in the outer SSD viscous heating is irradiated through the surface, radiative processes become very ineffective due to small optical depth in the inner ADAF. Here viscous heating is balanced by advective cooling, ie. is transported with the flow towards the central object. Near the transition turbulent convection pumps energy from the hot ADAF along the outward entropy gradient upwind against the flow into the transition region. There the associated flux drops sharply due to sharply decreasing temperature. The deposited energy is orders of magnitude larger and viscous heating and can only be balanced by increased radiative cooling. On the other hand photons escapes radially from the optically thick SSD into the optically thin ADAF where we expect them to be comptonized and could explain the hart part of the spectrum.

  6. Defining and Quantifying Globalization

    DTIC Science & Technology

    2006-03-08

    to be one of the most powerful issues facing the world today. Anthony Giddens , director of the London School of Economics, states the globalization...globalization is a central theme throughout this work. 12 Anthony Giddens , The Consequences of Modernity (Cambridge: Polity Press, 1990), 64. 13 Thomas...of the world such that space is no longer mapped in terms of physical geography to include distances and borders. In support of this view, Anthony

  7. Global Positioning System Status

    DTIC Science & Technology

    2011-04-27

    GPS : FREE – DEPENDABLE – RELIABLE - ACCURATE 1 GLOBAL POSITIONING SYSTEM STATUS Benjamin Barbour Major, United States Air Force Schriever AFB... Global Positioning System Service Interface Committee (CGSIC) held in Groton, CT, April 2011 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY...Continuing work with international GNSS community  Maintains Backward Compatibility  Managing GPS systems and supporting stakeholders Committed to responsible stewardship of GPS

  8. Percolation-based precursors of transitions in dynamical systems

    NASA Astrophysics Data System (ADS)

    Rodriguez Mendez, Victor Manuel; Eguiluz, Victor M.; Ramasco, Jose J.; Hernandez-Garcia, Emilio

    2015-04-01

    Transitions in complex dynamical systems are ubiquitous in nature. Finding leading indicators in such systems is a fundamental task in many areas of science, such as financial markets, the extinction of species or climate change studies. Here we propose a new framework to study systems close to a bifurcation point by analyzing topological properties, based on clusters and percolation, of functional networks defined from the time series. The use of networks allows us for a global parametrization of the system going far beyond simple two-point relations (classical correlations). The generality and versatility of the cluster-based method to forecast transitions is shown in two different kinds of data. In one hand, three theoretical dynamical systems displaying very different transitions and crossovers were used as a test bed. On the other hand, we have used the field of surface air temperature in the NINO 3.4 zone. In this new approach, critical transitions are identified before they occur.

  9. USGS global change research

    USGS Publications Warehouse

    ,

    1995-01-01

    The Earth's global environment--its interrelated climate, land, oceans, fresh water, atmospheric and ecological systems-has changed continually throughout Earth history. Human activities are having ever-increasing effects on these systems. Sustaining our environment as population and demands for resources increase requires a sound understanding of the causes and cycles of natural change and the effects of human activities on the Earth's environmental systems. The U.S. Global Change Research Program was authorized by Congress in 1989 to provide the scientific understanding necessary to develop national and international policies concerning global environmental issues, particularly global climate change. The program addresses questions such as: what factors determine global climate; have humans already begun to change the global climate; will the climate of the future be very different; what will be the effects of climate change; and how much confidence do we have in our predictions? Through understanding, we can improve our capability to predict change, reduce the adverse effects of human activities, and plan strategies for adapting to natural and human-induced environmental change.

  10. Is Global Warming Accelerating?

    NASA Astrophysics Data System (ADS)

    Shukla, J.; Delsole, T. M.; Tippett, M. K.

    2009-12-01

    A global pattern that fluctuates naturally on decadal time scales is identified in climate simulations and observations. This newly discovered component, called the Global Multidecadal Oscillation (GMO), is related to the Atlantic Meridional Oscillation and shown to account for a substantial fraction of decadal fluctuations in the observed global average sea surface temperature. IPCC-class climate models generally underestimate the variance of the GMO, and hence underestimate the decadal fluctuations due to this component of natural variability. Decomposing observed sea surface temperature into a component due to anthropogenic and natural radiative forcing plus the GMO, reveals that most multidecadal fluctuations in the observed global average sea surface temperature can be accounted for by these two components alone. The fact that the GMO varies naturally on multidecadal time scales implies that it can be predicted with some skill on decadal time scales, which provides a scientific rationale for decadal predictions. Furthermore, the GMO is shown to account for about half of the warming in the last 25 years and hence a substantial fraction of the recent acceleration in the rate of increase in global average sea surface temperature. Nevertheless, in terms of the global average “well-observed” sea surface temperature, the GMO can account for only about 0.1° C in transient, decadal-scale fluctuations, not the century-long 1° C warming that has been observed during the twentieth century.

  11. Globalization and Science Education

    NASA Astrophysics Data System (ADS)

    Bencze, J. Lawrence; Carter, Lyn; Chiu, Mei-Hung; Duit, Reinders; Martin, Sonya; Siry, Christina; Krajcik, Joseph; Shin, Namsoo; Choi, Kyunghee; Lee, Hyunju; Kim, Sung-Won

    2012-12-01

    Processes of globalization have played a major role in economic and cultural change worldwide. More recently, there is a growing literature on rethinking science education research and development from the perspective of globalization. This paper provides a critical overview of the state and future development of science education research from the perspective of globalization. Two facets are given major attention. First, the further development of science education as an international research domain is critically analyzed. It seems that there is a predominance of researchers stemming from countries in which English is the native language or at least a major working language. Second, the significance of rethinking the currently dominant variants of science instruction from the perspectives of economic and cultural globalization is given major attention. On the one hand, it is argued that processes concerning globalization of science education as a research domain need to take into account the richness of the different cultures of science education around the world. At the same time, it is essential to develop ways of science instruction that make students aware of the various advantages, challenges and problems of international economic and cultural globalization.

  12. Globalization and Science Education

    NASA Astrophysics Data System (ADS)

    Bencze, J. Lawrence; Carter, Lyn; Chiu, Mei-Hung; Duit, Reinders; Martin, Sonya; Siry, Christina; Krajcik, Joseph; Shin, Namsoo; Choi, Kyunghee; Lee, Hyunju; Kim, Sung-Won

    2013-06-01

    Processes of globalization have played a major role in economic and cultural change worldwide. More recently, there is a growing literature on rethinking science education research and development from the perspective of globalization. This paper provides a critical overview of the state and future development of science education research from the perspective of globalization. Two facets are given major attention. First, the further development of science education as an international research domain is critically analyzed. It seems that there is a predominance of researchers stemming from countries in which English is the native language or at least a major working language. Second, the significance of rethinking the currently dominant variants of science instruction from the perspectives of economic and cultural globalization is given major attention. On the one hand, it is argued that processes concerning globalization of science education as a research domain need to take into account the richness of the different cultures of science education around the world. At the same time, it is essential to develop ways of science instruction that make students aware of the various advantages, challenges and problems of international economic and cultural globalization.

  13. Alternative fuel transit buses: The Pierce Transit Success Story

    SciTech Connect

    1996-10-01

    The Pierce transit program for operating mass transit buses on compressed natural gas (CNG) is described. Cost, reliability, fuel efficiency, emission of combustion products, and future trends are discussed.

  14. Global challenges and globalization of bioethics

    PubMed Central

    Nezhmetdinova, Farida

    2013-01-01

    This article analyzes problems and implications for man and nature connected with the formation of a new architecture of science, based on the convergence of nanotechnology, biotechnology, information technology, and cognitive science (NBIC). It also describes evolution and genesis of bioethics, a scientific discipline and social practice with a special role of ethical management of potential risks of scientific research. The aim was to demonstrate the necessity of bioethical social control in the development of a global bioeconomy driven by NBIC technologies. PMID:23447421

  15. Global Self-Esteem, Appearance Satisfaction, and Self-Reported Dieting in Early Adolescence

    ERIC Educational Resources Information Center

    Barker, Erin T.; Bornstein, Marc H.

    2010-01-01

    Global self-esteem, appearance satisfaction, and self-reported dieting are interrelated. This study examines the temporal ordering of global self-esteem and appearance satisfaction across the early adolescence transition, from age 10 to age 14, as well as the independent associations of self-esteem and appearance satisfaction on self-reported…

  16. Global mental health and neuroscience: potential synergies.

    PubMed

    Stein, Dan J; He, Yanling; Phillips, Anthony; Sahakian, Barbara J; Williams, John; Patel, Vikram

    2015-02-01

    Global mental health has emerged as an important specialty. It has drawn attention to the burden of mental illness and to the relative gap in mental health research and services around the world. Global mental health has raised the question of whether this gap is a developmental issue, a health issue, a human rights issue, or a combination of these issues-and it has raised awareness of the need to develop new approaches for building capacity, mobilising resources, and closing the research and treatment gap. Translational neuroscience has also advanced. It comprises an important conceptual approach to understanding the neurocircuitry and molecular basis of mental disorders, to rethinking how best to undertake research on the aetiology, assessment, and treatment of these disorders, with the ultimate aim to develop entirely new approaches to prevention and intervention. Some apparent contrasts exist between these fields; global mental health emphasises knowledge translation, moving away from the bedside to a focus on health systems, whereas translational neuroscience emphasises molecular neuroscience, focusing on transitions between the bench and bedside. Meanwhile, important opportunities exist for synergy between the two paradigms, to ensure that present opportunities in mental health research and services are maximised. Here, we review the approaches of global mental health and clinical neuroscience to diagnosis, pathogenesis, and intervention, and make recommendations for facilitating an integration of these two perspectives.

  17. Global surgery: A view from the south.

    PubMed

    Roy, Nobhojit

    2017-02-01

    This article is based on the Hugh Greenwood Lecture delivered at the 2016 Congress of the British Association of Paediatric Surgeons. It presents the view of the global surgery movement from the bottom of the surgical food chain and proposes what HICs (high-income countries) can do for global surgery in a coordinated fashion. From the LMIC (low- and middle-income countries) surgeon perspective, global surgery is transitioning from the charity-based surgery model to codevelopment with multiple stakeholders. The caveats and current opportunities are described using two case studies. Surgeons may not play a pivotal role in the solutions. The future of the surgical workforce, innovation, workarounds, unmet burden of disease, and health metrics are discussed and multidisciplinary solutions proposed for the entire chain of surgical healthcare delivery in LMIC. A new breed of "essential surgeons", technology solutions for intellectual and physical isolation, competency-based credentialing, industry-driven innovation, task sharing over task shifting, prioritizing delivery based on surgical burden, and a rota-based overseas model of help are proposed as solutions for the issues facing global surgery.

  18. Miniaturization and globalization of clinical laboratory activities.

    PubMed

    Melo, Murilo R; Clark, Samantha; Barrio, Daniel

    2011-04-01

    Clinical laboratories provide an invaluable service to millions of people around the world in the form of quality diagnostic care. Within the clinical laboratory industry the impetus for change has come from technological development (miniaturization, nanotechnology, and their collective effect on point-of-care testing; POCT) and the increasingly global nature of laboratory services. Potential technological gains in POCT include: the development of bio-sensors, microarrays, genetics and proteomics testing, and enhanced web connectivity. In globalization, prospective opportunities lie in: medical tourism, the migration of healthcare workers, cross-border delivery of testing, and the establishment of accredited laboratories in previously unexplored markets. Accompanying these impressive opportunities are equally imposing challenges. Difficulty transitioning from research to clinical use, poor infrastructure in developing countries, cultural differences and national barriers to global trade are only a few examples. Dealing with the issues presented by globalization and the impact of developing technology on POCT, and on the clinical laboratory services industry in general, will be a daunting task. Despite such concerns, with appropriate countermeasures it will be possible to address the challenges posed. Future laboratory success will be largely dependent on one's ability to adapt in this perpetually shifting landscape.

  19. Transitions: exploring the frontier.

    PubMed

    Corless, Inge B

    End-of-life experiences go by various terms, including near-death experiences (NDEs), death bed visions, death bed phenomena, death bed coincidences, and nearing death awareness. Death bed escorts is the term applied to the vision of deceased family members or friends who inform the dying person that they will be accompanied in the transition from life. In this article, I examine the subject of NDEs and death bed escorts, starting with the rich body of work provided by Robert and Beatrice Kastenbaum. A subject of some interest to Robert Kastenbaum, he explored this frontier in his many writings on dying, death, and bereavement. Ever the pioneer and having made the ultimate transition, he may yet be exploring new frontiers.

  20. Emergence and Phase Transitions

    NASA Astrophysics Data System (ADS)

    Sikkema, Arnold

    2006-05-01

    Phase transitions are well defined in physics through concepts such as spontaneous symmetry breaking, order parameter, entropy, and critical exponents. But emergence --- also exhibiting whole-part relations (such as top-down influence), unpredictability, and insensitivity to microscopic detail --- is a loosely-defined concept being used in many disciplines, particularly in psychology, biology, philosophy, as well as in physics[1,2]. I will review the concepts of emergence as used in the various fields and consider the extent to which the methods of phase transitions can clarify the usefulness of the concept of emergence both within the discipline of physics and beyond.1. Robert B. Laughlin, A Different Universe: Reinventing Physics from the Bottom Down (New York: Basic Books, 2005). 2. George F.R. Ellis, ``Physics and the Real World'', Physics Today, vol. 58, no. 7 (July 2005) pp. 49-54.

  1. The Need for Transition

    DTIC Science & Technology

    2013-05-01

    assumptions. According to the original plan and assumptions, the Iraqi Police forces, which intelligence sources asserted were going to capitulate and...higher. This was all a result of failed assumptions in the prewar planning. Colonel Gregory Gardner , a member of the Joint Staff and then also on the...Institute (PKSOI) held a two day conference with multiple forces and international partners involved just to try and define transition. Each one of these

  2. Stimulated coherent transition radiation

    SciTech Connect

    Hung-chi Lihn

    1996-03-01

    Coherent radiation emitted from a relativistic electron bunch consists of wavelengths longer than or comparable to the bunch length. The intensity of this radiation out-numbers that of its incoherent counterpart, which extends to wavelengths shorter than the bunch length, by a factor equal to the number of electrons in the bunch. In typical accelerators, this factor is about 8 to 11 orders of magnitude. The spectrum of the coherent radiation is determined by the Fourier transform of the electron bunch distribution and, therefore, contains information of the bunch distribution. Coherent transition radiation emitted from subpicosecond electron bunches at the Stanford SUNSHINE facility is observed in the far-infrared regime through a room-temperature pyroelectric bolometer and characterized through the electron bunch-length study. To measure the bunch length, a new frequency-resolved subpicosecond bunch-length measuring system is developed. This system uses a far-infrared Michelson interferometer to measure the spectrum of coherent transition radiation through optical autocorrelation with resolution far better than existing time-resolved methods. Hence, the radiation spectrum and the bunch length are deduced from the autocorrelation measurement. To study the stimulation of coherent transition radiation, a special cavity named BRAICER is invented. Far-infrared light pulses of coherent transition radiation emitted from electron bunches are delayed and circulated in the cavity to coincide with subsequent incoming electron bunches. This coincidence of light pulses with electron bunches enables the light to do work on electrons, and thus stimulates more radiated energy. The possibilities of extending the bunch-length measuring system to measure the three-dimensional bunch distribution and making the BRAICER cavity a broadband, high-intensity, coherent, far-infrared light source are also discussed.

  3. Transition Region Flows

    NASA Astrophysics Data System (ADS)

    Brekke, P.; Murdin, P.

    2000-11-01

    Ultraviolet emission lines emitted from the SOLAR TRANSITION REGION are often shifted from their expected rest wavelengths. Shifts of spectral lines are due to the so-called DOPPLER EFFECT, where the source of emission is moving either away from or towards the observer, causing a change in the apparent wavelength. The shifted emission lines are most often interpreted as a flow of plasma along ...

  4. The Myths of Mass Transit.

    ERIC Educational Resources Information Center

    Burke, Catherine G.

    1982-01-01

    Criticizes eight commonly held notions about the value of mass transit systems in public transportation programs. Alternative approaches for improving the quality and quantity of urban transit systems are discussed. (AM)

  5. Psychological Aspects of Transitive Verbs

    ERIC Educational Resources Information Center

    Polzella, Donald J.; Rohrman, Nicholas L.

    1970-01-01

    The experiments reported here confirmed the findings of earlier researchers that transitive verbs are more difficult to recall than intransitive ones and furthermore established a close relationship between transitive verbs and nouns. Implications for linguistic theory are discussed. (FB)

  6. Youths Transitioning as Adult Learners

    ERIC Educational Resources Information Center

    Davis, C. Amelia

    2014-01-01

    This chapter considers how transitions to adulthood have been historically represented and presents alternative ways of thinking about transitions to adulthood through the context of adult basic education programs.

  7. Transition mixing study

    NASA Technical Reports Server (NTRS)

    Reynolds, R.; White, C.

    1986-01-01

    A computer model capable of analyzing the flow field in the transition liner of small gas turbine engines is developed. A FORTRAN code has been assembled from existing codes and physical submodels and used to predict the flow in several test geometries which contain characteristics similar to transition liners, and for which experimental data was available. Comparisons between the predictions and measurements indicate that the code produces qualitative results but that the turbulence models, both K-E and algebraic Reynolds Stress, underestimate the cross-stream diffusion. The code has also been used to perform a numerical experiment to examine the effect of a variety of parameters on the mixing process in transition liners. Comparisons illustrate that geometries with significant curvature show a drift of the jet trajectory toward the convex wall and weaker wake region vortices and decreased penetration for jets located on the convex wall of the liner, when compared to jets located on concave walls. Also shown were the approximate equivalency of angled slots and round holes and a technique by which jet mixing correlations developed for rectangular channels can be used for can geometries.

  8. Dynamic rigidity transition

    NASA Astrophysics Data System (ADS)

    Åström, J. A.; Latva-Kokko, M.; Timonen, J.

    2003-01-01

    An inflated closed loop (or membrane) is used to demonstrate a dynamic rigidity transition that occurs when impact energy is added to the loop in static equilibrium at zero temperature. The only relevant parameter in this transition is the ratio of the energy needed to collapse the loop and the impact energy. When this ratio is below a threshold value close to unity, the loop collapses into a high-entropy floppy state, and it does not return to the rigid state unless the impact energy can escape. The internal oscillations are in the floppy state dominated by 1/f2 noise. When the ratio is above the threshold, the loop does not collapse, and the internal oscillations resulting from the impact are dominated by the eigenfrequencies of the stretched membrane. In this state, the loop can bounce for a long time. It is still an open question whether bouncing will eventually vanish or whether a stationary bouncing state will be reached. The dynamic transition between the floppy and the rigid state is discontinuous.

  9. NASA metric transition plan

    NASA Technical Reports Server (NTRS)

    1992-01-01

    NASA science publications have used the metric system of measurement since 1970. Although NASA has maintained a metric use policy since 1979, practical constraints have restricted actual use of metric units. In 1988, an amendment to the Metric Conversion Act of 1975 required the Federal Government to adopt the metric system except where impractical. In response to Public Law 100-418 and Executive Order 12770, NASA revised its metric use policy and developed this Metric Transition Plan. NASA's goal is to use the metric system for program development and functional support activities to the greatest practical extent by the end of 1995. The introduction of the metric system into new flight programs will determine the pace of the metric transition. Transition of institutional capabilities and support functions will be phased to enable use of the metric system in flight program development and operations. Externally oriented elements of this plan will introduce and actively support use of the metric system in education, public information, and small business programs. The plan also establishes a procedure for evaluating and approving waivers and exceptions to the required use of the metric system for new programs. Coordination with other Federal agencies and departments (through the Interagency Council on Metric Policy) and industry (directly and through professional societies and interest groups) will identify sources of external support and minimize duplication of effort.

  10. Column continuous transition functions

    NASA Astrophysics Data System (ADS)

    Li, Yangrong

    2007-04-01

    A column continuous transition function is by definition a standard transition function P(t) whose every column is continuous for t[greater-or-equal, slanted]0 in the norm topology of bounded sequence space l[infinity]. We will prove that it has a stable q-matrix and that there exists a one-to-one relationship between column continuous transition functions and increasing integrated semigroups on l[infinity]. Using the theory of integrated semigroups, we give some necessary and sufficient conditions under which the minimal q-function is column continuous, in terms of its generator (of the Markov semigroup) as well as its q-matrix. Furthermore, we will construct all column continuous Q-functions for a conservative, single-exit and column bounded q-matrix Q. As applications, we find that many interesting continuous-time Markov chains (CTMCs), say Feller-Reuter-Riley processes, monotone processes, birth-death processes and branching processes, etc., have column continuity.

  11. Global Aspects of Radiation Memory

    NASA Astrophysics Data System (ADS)

    Winicour, Jeffrey

    2015-04-01

    The gravitational radiation memory effect produces a net displacement of test particles. The proposed sources lead to E mode memory, as characterized by an even parity polarization pattern. Although odd parity, or B mode, radiation memory is mathematically possible, no physically realistic source has been identified. There is an electromagnetic counterpart to radiation memory which produces a net momentum ``kick'' of charged test particles. A global null cone treatment shows that electromagnetic E mode memory requires unbounded charges and no physically realistic source produces B mode memory. A compelling theoretical aspect of E mode gravitational radiation memory is related to the supertranslations in the Bondi-Metzner-Sachs (BMS) asymptotic symmetry group. For a stationary system, supertranslations can be eliminated and the BMS group reduced to the Poincare group, for which angular momentum is well-defined. However, for a stationary to stationary transition, the two Poincare groups obtained at early and late times differ by a supertranslation if the gravitational radiation has nonzero E mode memory. This suggests a distinctly general relativistic mechanism for angular momentum loss and presents a ripe problem for the numerical simulation of high spin black hole binaries. Supported by NSF grant PHY-1201276 to the University of Pittsburgh.

  12. The transition to agricultural sustainability

    PubMed Central

    Ruttan, Vernon W.

    1999-01-01

    The transition to sustainable growth in agricultural production during the 21st century will take place within the context of a transition to a stable population and a possible transition to a stable level of material consumption. If the world fails to successfully navigate a transition to sustainable growth in agricultural production, the failure will be due more to a failure in the area of institutional innovation than to resource and environmental constraints. PMID:10339524

  13. Visual Analytics Technology Transition Progress

    SciTech Connect

    Scholtz, Jean; Cook, Kristin A.; Whiting, Mark A.; Lemon, Douglas K.; Greenblatt, Howard

    2009-09-23

    The authors provide a description of the transition process for visual analytic tools and contrast this with the transition process for more traditional software tools. This paper takes this into account and describes a user-oriented approach to technology transition including a discussion of key factors that should be considered and adapted to each situation. The progress made in transitioning visual analytic tools in the past five years is described and the challenges that remain are enumerated.

  14. Quantum Phase Transitions in Antiferromagnets and Superfluids

    NASA Astrophysics Data System (ADS)

    Sachdev, Subir

    2000-03-01

    A general introduction to the non-zero temperature dynamic and transport properties of low-dimensional systems near a quantum phase transition shall be presented. Basic results will be reviewed in the context of experiments on the spin-ladder compounds. Recent large N computations (M. Vojta and S. Sachdev, Phys. Rev. Lett. 83), 3916 (1999) on an extended t-J model motivate a global scenario of the quantum phases and transitions in the high temperature superconductors, and connections will be made to numerous experiments. A universal theory (S. Sachdev, C. Buragohain, and M. Vojta, Science, in press M. Vojta, C. Buragohain, and S. Sachdev, cond- mat/9912020) of quantum impurities in spin-gap antiferromagnets near a magnetic ordering transition will be compared quantitatively to experiments on Zn doped Y Ba2 Cu3 O7 (Fong et al.), Phys. Rev. Lett. 82, 1939 (1999)

  15. Phase transitions in Pareto optimal complex networks

    NASA Astrophysics Data System (ADS)

    Seoane, Luís F.; Solé, Ricard

    2015-09-01

    The organization of interactions in complex systems can be described by networks connecting different units. These graphs are useful representations of the local and global complexity of the underlying systems. The origin of their topological structure can be diverse, resulting from different mechanisms including multiplicative processes and optimization. In spatial networks or in graphs where cost constraints are at work, as it occurs in a plethora of situations from power grids to the wiring of neurons in the brain, optimization plays an important part in shaping their organization. In this paper we study network designs resulting from a Pareto optimization process, where different simultaneous constraints are the targets of selection. We analyze three variations on a problem, finding phase transitions of different kinds. Distinct phases are associated with different arrangements of the connections, but the need of drastic topological changes does not determine the presence or the nature of the phase transitions encountered. Instead, the functions under optimization do play a determinant role. This reinforces the view that phase transitions do not arise from intrinsic properties of a system alone, but from the interplay of that system with its external constraints.

  16. Analyses of some exoplanets' transits and transit timing variations

    NASA Astrophysics Data System (ADS)

    Püsküllü, ćaǧlar; Soydugan, Faruk

    2017-02-01

    We present solutions of the transit light curves and transit timing variations (TTVs) analyses of the exoplanets HAT-P-5b, HAT-P-9b and HAT-P-25b. Transit light curves were collected at Çanakkale Onsekiz Mart University Observatory and TUBITAK National Observatory. The models were produced by WINFITTER program and stellar, planetary and orbital properties were obtained and discussed. We gave new transit times and generated TTVs with them by appending additional data based on Exoplanet Transit Database (ETD). Significant signals at the TTVs were also investigated.

  17. Slow Transit Constipation.

    PubMed

    Wald, Arnold

    2002-08-01

    The diagnosis of slow transit functional constipation is based upon diagnostic testing of patients with idiopathic constipation who responded poorly to conservative measures such as fiber supplements, fluids, and stimulant laxatives. These tests include barium enema or colonoscopy, colonic transit of radio-opaque markers, anorectal manometry, and expulsion of a water-filled balloon. Plain abdominal films can identify megacolon, which can be further characterized by barium or gastrografin studies. Colonic transit of radio-opaque markers identifies patients with slow transit with stasis of markers in the proximal colon. However, anorectal function should be characterized to exclude outlet dysfunction, which may coexist with colonic inertia. Because slow colonic transit is defined by studies during which patients consume a high-fiber diet, fiber supplements are generally not effective, nor are osmotic laxatives that consist of unabsorbed sugars. Stimulant laxatives are considered first-line therapy, although studies often show a diminished colonic motor response to such agents. There is no evidence to suggest that chronic use of such laxatives is harmful if they are used two to three times per week. Polyethylene glycol with or without electrolytes may be useful in a minority of patients, often combined with misoprostol. I prefer to start with misoprostol 200 mg every other morning and increase to tolerance or efficacy. I see no advantage in prescribing misoprostol on a TID or QID basis or even daily because it increases cramping unnecessarily. This drug is not acceptable in young women who wish to become pregnant. An alternative may be colchicine, which is reported to be effective when given as 0.6 mg TID. Long-term efficacy has not been studied. Finally, biofeedback is a risk-free approach that has been reported as effective in approximately 60% of patients with slow transit constipation in the absence of outlet dysfunction. Although difficult to understand

  18. The Global Schoolgirl

    ERIC Educational Resources Information Center

    Chickering, Lawrence; Tyagi, Anjula

    2012-01-01

    The challenges of poverty and development have long been regarded in terms of transitive relationships, in which the rich help the poor because the poor are not seen as able to help themselves. This view of the poor assumes they have mainly needs and no assets. With so many people believing this view it isn't surprising that the poor themselves…

  19. Developing Global Nurse Influencers.

    PubMed

    Spies, Lori A

    2016-01-01

    How can universities create engaged citizens and global leaders? Each year, a select group of advanced practice nursing students at Baylor University Louise Herrington School of Nursing travel to Africa for a month-long clinical mission experience. Students work alongside local and missionary healthcare providers in a comprehensive Christian outreach to the community at a high-volume clinic. Creating rich learning experiences in a global setting in significant and sustainable ways is difficult, but intentionally focusing on what we are called to do and who we serve provides ballast for faculty and students. The success of the trip in preparing students to be global influencers is evident by the work graduates elect to do around the world, following graduation.

  20. Global ice sheet modeling

    SciTech Connect

    Hughes, T.J.; Fastook, J.L.

    1994-05-01

    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed.

  1. Global weather research

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Modeling, prediction, and analysis of global meteorological phenomena influencing the large scale behavior of the atmosphere are summarized. Prediction of global weather phenomena based on satellite data is discussed and models of global phenomena developed. The atmospheric general circulation model (AGCE) is reviewed, axisymmetric flow calculated, and axisymmetric states in cylindrical, spherical, three dimensional, and spin up numerical models for AGCE described. The role of latent heat release in baroclinic waves, latent heat and cyclonic systems, and a theoretical study of baroclinic flow related to the AGCE and the flow regime were studied with a simplified general circulation model. AGCE and the geophysical fluid flow cell (GFFC) instrumentation are discussed. Investigation of solar and planetary convection for GFFC is described. The utilization of satellite cloud observations to diagnose the energy state and transformations in extratropical cyclones is reviewed.

  2. The global sulfur cycle

    NASA Technical Reports Server (NTRS)

    Sagan, D. (Editor)

    1985-01-01

    The results of the planetary biology microbial ecology's 1984 Summer Research Program, which examined various aspects of the global sulfur cycle are summarized. Ways in which sulfur flows through the many living and chemical species that inhabit the surface of the Earth were investigated. Major topics studied include: (1) sulfur cycling and metabolism of phototropic and filamentous sulfur bacteria; (2) sulfur reduction in sediments of marine and evaporite environments; (3) recent cyanobacterial mats; (4) microanalysis of community metabolism in proximity to the photic zone in potential stromatolites; and (5) formation and activity of microbial biofilms on metal sulfides and other mineral surfaces. Relationships between the global sulfur cycle and the understanding of the early evolution of the Earth and biosphere and current processes that affect global habitability are stressed.

  3. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    SciTech Connect

    Chandler, K.; Eudy, L.

    2007-03-01

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  4. The global water cycle

    NASA Astrophysics Data System (ADS)

    Oki, Taikan; Entekhabi, Dara; Harrold, Timothy Ives

    The global water cycle consists of the oceans, water in the atmosphere, and water in the landscape. The cycle is closed by the fluxes between these reservoirs. Although the amounts of water in the atmosphere and river channels are relatively small, the fluxes are high, and this water plays a critical role in society, which is dependent on water as a renewable resource. On a global scale, the meridional component of river runoff is shown to be about 10% of the corresponding atmospheric and oceanic meridional fluxes. Artificial storages and water withdrawals for irrigation have significant impacts on river runoff and hence on the overall global water cycle. Fully coupled atmosphere-land-river-ocean models of the world's climate are essential to assess the future water resources and scarcities in relation to climate change. An assessment of future water scarcity suggests that water shortages will worsen, with a very significant increase in water stress in Africa. The impact of population growth on water stress is shown to be higher than that of climate change. The virtual water trade, which should be taken into account when discussing the global water cycle and water scarcity, is also considered. The movement of virtual water from North America, Oceania, and Europe to the Middle East, North West Africa, and East Asia represents significant global savings of water. The anticipated world water crisis widens the opportunities for the study of the global water cycle to contribute to the development of sustainability within society and to the solution of practical social problems.

  5. The global drug gap.

    PubMed

    Reich, M R

    2000-03-17

    Global inequities in access to pharmaceutical products exist between rich and poor countries because of market and government failures as well as huge income differences. Multiple policies are required to address this global drug gap for three categories of pharmaceutical products: essential drugs, new drugs, and yet-to-be-developed drugs. Policies should combine "push" approaches of subsidies to support targeted drug development, "pull" approaches of financial incentives such as market guarantees, and "process" approaches aimed at improved institutional capacity. Constructive solutions are needed that can both protect the incentives for research and development and reduce the inequities of access.

  6. Globalization and infectious diseases.

    PubMed

    Frenk, Julio; Gómez-Dantés, Octavio; Knaul, Felicia M

    2011-09-01

    This article discusses the nature of the health challenges created by globalization and proposes new forms of international cooperation to confront them. The discussion of global health challenges includes both the transfer of health risks, with an emphasis on infectious diseases, and the international dissemination of health opportunities, including the transfer of knowledge and technology. The authors argue that the health-related challenges and opportunities of an increasingly interdependent world demand new forms of international cooperation. The authors suggest the promotion of 3 elements that, in their essence, contain the idea of collaboration: exchange, evidence, and empathy.

  7. Global Biogeochemistry: an Overview

    NASA Technical Reports Server (NTRS)

    Moore, B., III

    1984-01-01

    The dynamic biogeochemical equilibria among the major pools of carbon, nitrogen, sulfur, and phosphorus represented by terrestrial biomes, the world's oceans, and the troposphere are disturbed. Since even the most rapid processes of adjustments among the reservoirs take decades, new equilibria are far from established. These human-induced perturbations and the system's subsequent responses constitute an on-going biogeochemical experiment at the global level. Current and new information must be combined in a way that allows testing of various hypotheses about the workings of global biogeochemical systems. This enables assessment of current knowledge and evaluation of the gaps.

  8. Global environmental report card

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    Worldwatch Institute, a Washington, D.C.-based think tank, issued a gloomy yet hopeful annual “State of the World” report on global environmental trends on 10 January.The report notes some recent successful efforts to protect the environment, including the phasing out of the production of ozone-depleting chlorofluorocarbons (CFCs) and the 2001 signing of the Stockholm Convention on Persistent Organic Pollutants (POPs). Nonetheless, the report calls for a global war on environmental degradation “that is as aggressive and well-funded as the war on terrorism” following the 11 September terrorist attacks in the United States.

  9. The Global Environment

    NASA Astrophysics Data System (ADS)

    Moore, John W.

    2003-10-01

    What can we teachers do? For students we can provide a strong background in the process of science and in scientific ethics. We can encourage students to apply such knowledge wisely throughout their lives. For the public at large, we can speak out in favor of real science at every opportunity. It is possible that the current scientific consensus on global warming is based on incomplete evidence, but global warming ought not be dismissed as unscientific or a hoax, and scientists ought not allow that to happen. As we celebrate National Chemistry Week, we should resolve to support chemistry and science as strongly as we can.

  10. Global aphasia without hemiparesis.

    PubMed

    Tranel, D; Biller, J; Damasio, H; Adams, H P; Cornell, S H

    1987-03-01

    Three patients acutely developed global aphasia, but did not manifest the typical accompanying right hemiparesis. Computed tomography and magnetic resonance imaging studies demonstrated that the patients had two discrete left hemisphere lesions, one in the anterior language cortices or language-related subcortical areas, and one in the posterior language cortices. Cerebral angiography showed that two patients had complete occlusion of the left internal carotid artery, and the third had an intraluminal "clot" in the supraclinoid portion of the left internal carotid, findings suggestive of an embolic etiology. Our cases indicate that global aphasia without hemiparesis predicts two discrete lesions and a particularly good recovery of speech and language.

  11. Global Ocean Phytoplankton

    NASA Technical Reports Server (NTRS)

    Franz, B. A.; Behrenfeld, M. J.; Siegel, D. A.; Werdell, P. J.

    2013-01-01

    Phytoplankton are free-floating algae that grow in the euphotic zone of the upper ocean, converting carbon dioxide, sunlight, and available nutrients into organic carbon through photosynthesis. Despite their microscopic size, these photoautotrophs are responsible for roughly half the net primary production on Earth (NPP; gross primary production minus respiration), fixing atmospheric CO2 into food that fuels our global ocean ecosystems. Phytoplankton thus play a critical role in the global carbon cycle, and their growth patterns are highly sensitive to environmental changes such as increased ocean temperatures that stratify the water column and prohibit the transfer of cold, nutrient richwaters to the upper ocean euphotic zone.

  12. Global water cycle

    NASA Technical Reports Server (NTRS)

    Robertson, Franklin R.; Christy, John R.; Goodman, Steven J.; Miller, Tim L.; Fitzjarrald, Dan; Lapenta, Bill; Wang, Shouping

    1991-01-01

    The primary objective is to determine the scope and interactions of the global water cycle with all components of the Earth system and to understand how it stimulates and regulates changes on both global and regional scales. The following subject areas are covered: (1) water vapor variability; (2) multi-phase water analysis; (3) diabatic heating; (4) MSU (Microwave Sounding Unit) temperature analysis; (5) Optimal precipitation and streamflow analysis; (6) CCM (Community Climate Model) hydrological cycle; (7) CCM1 climate sensitivity to lower boundary forcing; and (8) mesoscale modeling of atmosphere/surface interaction.

  13. Military Implications of Global Warming.

    DTIC Science & Technology

    2007-11-02

    U.S. environmental issues also have important global implications. This paper analyzes current U.S. Policy as it pertains to global warming and climate...for military involvement to reduce global warming . Global warming and other environmental issues are important to the U.S. military. As the United

  14. A translational evaluation of transitions.

    PubMed

    Jessel, Joshua; Hanley, Gregory P; Ghaemmaghami, Mahshid

    2016-06-01

    Transitions with nonhuman animals are typically framed as inescapable changes in signaled reinforcement schedules that result in a pause in responding unique to switches from rich to lean schedules. Pausing is considered to be a function of the aversive qualities of the contrasting reinforcement schedules. Transitions are typically framed in applied research as physical changes in location that evoke problem behavior maintained by the escape of an aversive event or resumption of a preferred event. We attempted to extend the basic framing of transitions to behaviors and contexts of social significance and evaluate a novel treatment for the problem of dawdling by 3 boys who had been diagnosed with autism spectrum disorder during rich-to-lean transitions. Dawdling during physical transitions was most readily observed when transitioning to lean contexts in Experiment 1. We then shortened transition duration in Experiment 2 by programming unsignaled and probabilistic rich reinforcement in the upcoming context.

  15. MINEHOUND: transition to production

    NASA Astrophysics Data System (ADS)

    Daniels, David J.; Curtis, Paul; Hunt, Nigel; Braunstein, Jürgen; Merz, Armin

    2007-04-01

    The UK Department for International Development (DfID), in collaboration with the German Foreign Ministry (Auswärtiges Amt), contracted ERA Technology to carry out extensive field trials in Cambodia, Bosnia and Angola of an advanced technology, dual sensor, and hand-held landmine detector system called MINEHOUND TM. This detector combines a metal detector with a Ground Penetrating Radar (GPR). As a result of extremely successful trials MINEHOUND TM was developed as a product by ERA Technology and Vallon GmbH and has been available for sale since late 2006. This paper describes the transition to production of the detector.

  16. Transition Path Theory

    NASA Astrophysics Data System (ADS)

    vanden-Eijnden, E.

    The dynamical behavior of many systems arising in physics, chemistry, biology, etc. is dominated by rare but important transition events between long lived states. For over 70 years, transition state theory (TST) has provided the main theoretical framework for the description of these events [17,33,34]. Yet, while TST and evolutions thereof based on the reactive flux formalism [1, 5] (see also [30,31]) give an accurate estimate of the transition rate of a reaction, at least in principle, the theory tells very little in terms of the mechanism of this reaction. Recent advances, such as transition path sampling (TPS) of Bolhuis, Chandler, Dellago, and Geissler [3, 7] or the action method of Elber [15, 16], may seem to go beyond TST in that respect: these techniques allow indeed to sample the ensemble of reactive trajectories, i.e. the trajectories by which the reaction occurs. And yet, the reactive trajectories may again be rather uninformative about the mechanism of the reaction. This may sound paradoxical at first: what more than actual reactive trajectories could one need to understand a reaction? The problem, however, is that the reactive trajectories by themselves give only a very indirect information about the statistical properties of these trajectories. This is similar to why statistical mechanics is not simply a footnote in books about classical mechanics. What is the probability density that a trajectory be at a given location in state-space conditional on it being reactive? What is the probability current of these reactive trajectories? What is their rate of appearance? These are the questions of interest and they are not easy to answer directly from the ensemble of reactive trajectories. The right framework to tackle these questions also goes beyond standard equilibrium statistical mechanics because of the nontrivial bias that the very definition of the reactive trajectories imply - they must be involved in a reaction. The aim of this chapter is to

  17. Transition Metal Switchable Mirror

    SciTech Connect

    2009-01-01

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  18. Transition Metal Switchable Mirror

    SciTech Connect

    2009-08-21

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  19. Transition Metal Switchable Mirror

    ScienceCinema

    None

    2016-07-12

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  20. Transition Metal Switchable Mirror

    ScienceCinema

    None

    2016-07-12

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  1. Transits of Venus and Colonial India

    NASA Astrophysics Data System (ADS)

    Kochhar, Rajesh

    2012-09-01

    Astronomical expeditions during the colonial period had a political and national significance also. Measuring the earth and mapping the sky were activities worthy of powerful and power- seeking nations. Such was the sanctity of global astronomical activity that many other agendas could be hidden under it. An early astronomy-related expedition turned out to be extremely beneficial, to botany. The expedition sent by the French Government in 1735 to South America under the leadership of Charles Marie de la Condamine (1701--1774) ostensibly for the measurement of an arc of the meridian at Quito in Ecuador surreptitiously collected data that enabled Linnaeus to describe the genus cinchona in 1742. When the pair of transits of Venus occurred in 1761 and 1769, France and England were engaged in a bitter rivalry for control of India. The observation of the transits became a part of the rivalry. A telescope presented by the British to a South Indian King as a decorative toy was borrowed back for actual use. Scientifically the transit observations were a wash out, but the exercise introduced Europe to details of living Indian tradition of eclipse calculations. More significantly, it led to the institutionalization of modern astronomy in India under the auspices of the English East India Company (1787). The transits of Venus of 1874 and 1882 were important not so much for the study of the events as for initiating systematic photography of the Sun. By this, Britain owned most of the world's sunshine, and was expected to help European solar physicists get data from its vast Empire on a regular basis. This and the then genuinely held belief that a study of the sun would help predict failure of monsoons led to the institutionalization of solar physics studies in India (1899). Of course, when the solar physicists learnt that solar activity did not quite determine rainfall in India, they forgot to inform the Government.

  2. Quantum phase transition induced by real-space topology

    NASA Astrophysics Data System (ADS)

    Li, C.; Zhang, G.; Lin, S.; Song, Z.

    2016-12-01

    A quantum phase transition (QPT), including both topological and symmetry breaking types, is usually induced by the change of global parameters, such as external fields or global coupling constants. In this work, we demonstrate the existence of QPT induced by the real-space topology of the system. We investigate the groundstate properties of the tight-binding model on a honeycomb lattice with the torus geometry based on exact results. It is shown that the ground state experiences a second-order QPT, exhibiting the scaling behavior, when the torus switches to a tube, which reveals the connection between quantum phase and the real-space topology of the system.

  3. Quantum phase transition induced by real-space topology

    PubMed Central

    Li, C.; Zhang, G.; Lin, S.; Song, Z.

    2016-01-01

    A quantum phase transition (QPT), including both topological and symmetry breaking types, is usually induced by the change of global parameters, such as external fields or global coupling constants. In this work, we demonstrate the existence of QPT induced by the real-space topology of the system. We investigate the groundstate properties of the tight-binding model on a honeycomb lattice with the torus geometry based on exact results. It is shown that the ground state experiences a second-order QPT, exhibiting the scaling behavior, when the torus switches to a tube, which reveals the connection between quantum phase and the real-space topology of the system. PMID:28004736

  4. NASA Global Hawk Overview

    NASA Technical Reports Server (NTRS)

    2011-01-01

    NASA Global Hawk is operational and supporting Earth science research. 29 Flights were conducted during the first year of operations, with a total of 253 flight hours. Three major science campaigns have been conducted with all objectives met. Two new science campaigns are in the planning stage

  5. Engineers: Going Global

    ERIC Educational Resources Information Center

    Feest, Tim

    2008-01-01

    This article demonstrates the need for engineering courses in UK higher education to give a higher priority to global and sustainability issues. In support of this case, the author summarizes and assesses evidence from a recently-concluded study by the Institute of Education, University of London, and Engineers Against Poverty, a specialist…

  6. Global Image Denoising.

    PubMed

    Talebi, Hossein; Milanfar, Peyman

    2014-02-01

    Most existing state-of-the-art image denoising algorithms are based on exploiting similarity between a relatively modest number of patches. These patch-based methods are strictly dependent on patch matching, and their performance is hamstrung by the ability to reliably find sufficiently similar patches. As the number of patches grows, a point of diminishing returns is reached where the performance improvement due to more patches is offset by the lower likelihood of finding sufficiently close matches. The net effect is that while patch-based methods, such as BM3D, are excellent overall, they are ultimately limited in how well they can do on (larger) images with increasing complexity. In this paper, we address these shortcomings by developing a paradigm for truly global filtering where each pixel is estimated from all pixels in the image. Our objectives in this paper are two-fold. First, we give a statistical analysis of our proposed global filter, based on a spectral decomposition of its corresponding operator, and we study the effect of truncation of this spectral decomposition. Second, we derive an approximation to the spectral (principal) components using the Nyström extension. Using these, we demonstrate that this global filter can be implemented efficiently by sampling a fairly small percentage of the pixels in the image. Experiments illustrate that our strategy can effectively globalize any existing denoising filters to estimate each pixel using all pixels in the image, hence improving upon the best patch-based methods.

  7. The Global Energy Budget.

    ERIC Educational Resources Information Center

    Jax, Daniel W.

    1992-01-01

    Presents a lesson plan about greenhouse effect and global warming. Includes diagrams and graphs from which students are asked to make inferences. Provides background information about how energy enters and leaves the earth system, the energy budget, consequences of obstructing the energy balance, and the greenhouse effect. (three references) (MCO)

  8. The Global Circuit.

    ERIC Educational Resources Information Center

    Lansford, Henry

    1983-01-01

    Discusses the nature of and research related to a theory explaining the earth's electric budget. The theory suggests a global electric circuit completed by a positive current flowing up into thunderstorm clouds, from clouds to ionosphere, distributed around the globe, and down to earth through the lower atmosphere in fair-weather regions. (JN)

  9. Global Learning Scales up

    ERIC Educational Resources Information Center

    Schachter, Ron

    2011-01-01

    Becoming more global is a familiar refrain for many a school administrator or curriculum developer wrestling with delivering 21st century skills. Over the past decade, districts have expanded their foreign language programs, added Mandarin Chinese to the mix, and in some cases launched language immersion classes in their elementary schools. Others…

  10. Vaccines: Shaping global health.

    PubMed

    Pagliusi, Sonia; Ting, Ching-Chia; Lobos, Fernando

    2017-03-14

    The Developing Countries Vaccine Manufacturers' Network (DCVMN) gathered leaders in immunization programs, vaccine manufacturing, representatives of the Argentinean Health Authorities and Pan American Health Organization, among other global health stakeholders, for its 17th Annual General Meeting in Buenos Aires, to reflect on how vaccines are shaping global health. Polio eradication and elimination of measles and rubella from the Americas is a result of successful collaboration, made possible by timely supply of affordable vaccines. After decades of intense competition for high-value markets, collaboration with developing countries has become critical, and involvement of multiple manufacturers as well as public- and private-sector investments are essential, for developing new vaccines against emerging infectious diseases. The recent Zika virus outbreak and the accelerated Ebola vaccine development exemplify the need for international partnerships to combat infectious diseases. A new player, Coalition for Epidemic Preparedness Innovations (CEPI) has made its entrance in the global health community, aiming to stimulate research preparedness against emerging infections. Face-to-face panel discussions facilitated the dialogue around challenges, such as risks of viability to vaccine development and regulatory convergence, to improve access to sustainable vaccine supply. It was discussed that joint efforts to optimizing regulatory pathways in developing countries, reducing registration time by up to 50%, are required. Outbreaks of emerging infections and the global Polio eradication and containment challenges are reminders of the importance of vaccines' access, and of the importance of new public-private partnerships.

  11. Geography and global health.

    PubMed

    Brown, Tim; Moon, Graham

    2012-01-01

    In the wake of the report of the World Health Organisation's Commission on the Social Determinants of Health, Closing the gap in a generation (Marmot 2008), this invited commentary considers the scope for geographical research on global health. We reflect on current work and note future possibilities, particularly those that take a critical perspective on the interplay of globalisation, security and health.

  12. Globalizing Space Security

    DTIC Science & Technology

    2003-01-01

    transferred to U.S. Strategic Command. The primary function of JTF/CNO is protecting Internet use within DOD. As threats such as computer worms and...almost total domi- nance over Internet use . This offers an easy means to reconfigure space and information systems. Since capabilities such as global

  13. Global Skill Shortages.

    ERIC Educational Resources Information Center

    Cohen, Malcolm S.; Zaidi, Mahmood A.

    This book discusses the causes and impact of global skill shortages, focusing on data from skill shortages measured in the period 1995-1998 in 19 developed and emerging economies. Chapter one contains a brief introduction. Chapter two is a review of theoretical literature on skill shortages, including static and dynamic shortages, efficiency wage…

  14. Globalism and Health

    ERIC Educational Resources Information Center

    Rowland, Michael L.

    2011-01-01

    With the advent of twenty-four-hour news media, local, state, and national agencies' warnings and with the explosive role of the Internet, people are more aware of global health concerns that may have significant consequences for the world's population. As international travel continues to increase, health care professionals around the world are…

  15. Making a global impact.

    PubMed

    2015-12-12

    How can vets, individually and collectively, make an impact on the global stage? Addressing this question at the BVA Congress at the London Vet Show, René Carlson, president of the World Veterinary Association, encouraged the profession to play its part locally, nationally and internationally, in tackling current challenges. Kristy Ebanks reports.

  16. [Globalization and infectious diseases].

    PubMed

    Mirski, Tomasz; Bartoszcze, Michał; Bielawska-Drózd, Agata

    2011-01-01

    Globalization is a phenomenon characteristic of present times. It can be considered in various aspects: economic, environmental changes, demographic changes, as well as the development of new technologies. All these aspects of globalization have a definite influence on the emergence and spread of infectious diseases. Economic aspects ofglobalization are mainly the trade development, including food trade, which has an impact on the spread of food-borne diseases. The environmental changes caused by intensive development of industry, as a result of globalization, which in turn affects human health. The demographic changes are mainly people migration between countries and rural and urban areas, which essentially favors the global spread of many infectious diseases. While technological advances prevents the spread of infections, for example through better access to information, it may also increase the risk, for example through to create opportunities to travel into more world regions, including the endemic regions for various diseases. The phenomenon ofglobalization is also closely associated with the threat of terrorism, including bioterrorism. It forces the governments of many countries to develop effective programs to protect and fight against this threat.

  17. Global Aerosol Observations

    Atmospheric Science Data Center

    2013-04-19

    ... atmosphere, directly influencing global climate and human health. Ground-based networks that accurately measure column aerosol amount and ... being used to improve Air Quality Models and for regional health studies. To assess the human-health impact of chronic aerosol exposure, ...

  18. Energy and Global Ethics.

    ERIC Educational Resources Information Center

    Reader, Mark

    1979-01-01

    Author believes that the nuclear fuel cycle is damaging to our health, physical system, ecosystem, and social system. He recommends reversing the trend toward nuclear power and solving the energy crisis by creating a global society able to live in balance with its physical environment. Journal available from 7 Harwood Drive, Amherst, New York…

  19. Global Is Local.

    ERIC Educational Resources Information Center

    Somerville, Mary R.

    1995-01-01

    By reflecting the new global community in staffing, collections, programs, exhibits, and services, public libraries will be fulfilling their role in the acculturation and education of new citizens, as well as contributing to greater community understanding and a new world order. A sidebar lists seven steps for serving recent immigrants. (AEF)

  20. Global Atmospheric Monitoring

    ERIC Educational Resources Information Center

    Wallen, Carl C.

    1975-01-01

    The global atmospheric monitoring plans of the World Meteorological Organization are detailed. Single and multipurpose basic monitoring systems and the monitoring of chemical properties are discussed. The relationship of the World Meteorological Organization with the United Nations environment program is discussed. A map of the World…

  1. A Global Perspective

    PubMed Central

    Harrison, Mark

    2015-01-01

    Summary The emergence of global history has been one of the more notable features of academic history over the past three decades. Although historians of disease were among the pioneers of one of its earlier incarnations—world history—the recent “global turn” has made relatively little impact on histories of health, disease, and medicine. Most continue to be framed by familiar entities such as the colony or nation-state or are confined to particular medical “traditions.” This article aims to show what can be gained from taking a broader perspective. Its purpose is not to replace other ways of seeing or to write a new “grand narrative” but to show how transnational and transimperial approaches are vital to understanding some of the key issues with which historians of health, disease, and medicine are concerned. Moving on from an analysis of earlier periods of integration, the article offers some reflections on our own era of globalization and on the emerging field of global health. PMID:26725408

  2. Tending the Global Commons.

    ERIC Educational Resources Information Center

    Ember, Lois R.; And Others

    1986-01-01

    Discusses the global trends associated with the increasing levels of carbon dioxide, nitrous oxide, methane, and chlorofluorocarbons (CFS) in the earth's atmosphere. Presents several ecological effects associated with these increases, along with some of the possible social and economic implications for the quality of life. Argues for more…

  3. Global Hawk Science Flights

    NASA Video Gallery

    The Global Hawk is a robotic plane that can fly altitudes above 60,000 feet (18.3 kilometers) -- roughly twice as high as a commercial airliner -- and as far as 11,000 nautical miles (20,000 kilome...

  4. GAR Global Risk Assessment

    NASA Astrophysics Data System (ADS)

    Maskrey, Andrew; Safaie, Sahar

    2015-04-01

    Disaster risk management strategies, policies and actions need to be based on evidence of current disaster loss and risk patterns, past trends and future projections, and underlying risk factors. Faced with competing demands for resources, at any level it is only possible to priorities a range of disaster risk management strategies and investments with adequate understanding of realised losses, current and future risk levels and impacts on economic growth and social wellbeing as well as cost and impact of the strategy. The mapping and understanding of the global risk landscape has been greatly enhanced by the latest iteration of the GAR Global Risk Assessment and the objective of this submission is to present the GAR global risk assessment which contributed to Global Assessment Report (GAR) 2015. This initiative which has been led by UNISDR, was conducted by a consortium of technical institutions from around the world and has covered earthquake, cyclone, riverine flood, and tsunami probabilistic risk for all countries of the world. In addition, the risks associated with volcanic ash in the Asia-Pacific region, drought in various countries in sub-Saharan Africa and climate change in a number of countries have been calculated. The presentation will share thee results as well as the experience including the challenges faced in technical elements as well as the process and recommendations for the future of such endeavour.

  5. Teaching global bioethics.

    PubMed

    Dwyer, James

    2003-10-01

    We live in a world with enormous disparities in health. The life expectancy in Japan is 80 years; in Malawi, 40 years. The under-five mortality in Norway is 4/1000; in Sierra Leone, 316/1000. The situation is actually worse than these figures suggest because average rates tend to mask inequalities within a country. Several presidents of the IAB have urged bioethicists to attend to global disparities and to broaden the scope of bioethics. For the last six years I have tried to do just that. In this paper, I report and reflect on my attempts to teach bioethics in ways that address global health and justice. I then discuss ways to address key ethical issues in global health: the problem of inequalities; the nature of the duty to assist; the importance of the duty not to harm; the difference between a cosmopolitan and a political view of justice. I also discuss how teaching about global health may help to shift the emphasis in bioethics--from sensational cases to everyday matters, from autonomy and justice, and from access to healthcare to the social determinants of health. At the end of my paper, I reflect on questions that I have not resolved: how to delineate the scope of bioethics, whether my approach over-politicises bioethics, and how to understand the responsibilities of bioethicists.

  6. Global Learning Quality

    ERIC Educational Resources Information Center

    Pawlowski, Jan M.

    2008-01-01

    Learning, education, and training becomes more and more internationalized. As examples, study programs are exported across borders, curricula are harmonized across Europe, learners work in globally distributed groups. However, the quality of educational offers differs dramatically. In this paper, an approach to manage quality for globally…

  7. Managing Global Problems.

    ERIC Educational Resources Information Center

    Stanley, C. Maxwell

    The book examines the historical background of and accomplishments in seven global problem areas. It is hypothesized that effective management within today's framework is the only way to progress toward the political and economic order that is necessary to assure peace and security, justice, and human rights, and to improve the quality of life. It…

  8. The Globalization of Racism

    ERIC Educational Resources Information Center

    Macedo, Donaldo; Gounari, Panayota

    2005-01-01

    Addressing ethnic cleansing, culture wars, human sufferings, terrorism, immigration, and intensified xenophobia, "Globalization of Racism" explains why it is vital that we gain a nuanced understanding of how ideology underlies all social, cultural, and political discourse and racist actions. The book looks at recent developments in…

  9. The Global Internet Pandemic

    ERIC Educational Resources Information Center

    Carter, Deborah Joy

    2009-01-01

    The global rise of Internet-based education is discussed in relation to models drawn from social studies and epidemiology. Experiential and data density models are highlighted, also the capacity for technological change, and phenomena observed in the spread of disease. The lesson of these illustrations is that even apparently permanent phenomena…

  10. Subnational Opposition to Globalization

    ERIC Educational Resources Information Center

    Almeida, Paul

    2012-01-01

    Using a unique dataset on the geographic distribution of reported protest events from local sources, the study explains the variation in community-level mobilization in response to neoliberal reforms in two countries in the global periphery. Building on insights from macro, cross-national studies of protests related to market reforms, this article…

  11. GLOBAL WATER RESEARCH COALITION

    EPA Science Inventory

    The Global Water Research Coalition (GWRC) is a collaboration of 14 member drinking and wastewater research organizations. The USEPA is currently a partner to the GWRC membership. Through the GWRC, the members are able to leverage research funds on mutually desired efforts to m...

  12. Global aspects of monsoons

    NASA Technical Reports Server (NTRS)

    Murakami, T.

    1985-01-01

    Recent developments are studied in three areas of monsoon research: (1) global aspects of the monsoon onset, (2) the orographic influence of the Tibetan Plateau on the summer monsoon circulations, and (3) tropical 40 to 50 day oscillations. Reference was made only to those studies that are primarily based on FGGE Level IIIb data. A brief summary is given.

  13. Global Ocean Phytoplankton

    NASA Technical Reports Server (NTRS)

    Franz, B. A.; Behrenfeld, M. J.; Siegel, D. A.; Werdell, P. J.

    2014-01-01

    Marine phytoplankton are responsible for roughly half the net primary production (NPP) on Earth, fixing atmospheric CO2 into food that fuels global ocean ecosystems and drives the ocean's biogeochemical cycles. Phytoplankton growth is highly sensitive to variations in ocean physical properties, such as upper ocean stratification and light availability within this mixed layer. Satellite ocean color sensors, such as the Sea-viewing Wide Field-of-view Sensor (SeaWiFS; McClain 2009) and Moderate Resolution Imaging Spectroradiometer (MODIS; Esaias 1998), provide observations of sufficient frequency and geographic coverage to globally monitor physically-driven changes in phytoplankton distributions. In practice, ocean color sensors retrieve the spectral distribution of visible solar radiation reflected upward from beneath the ocean surface, which can then be related to changes in the photosynthetic phytoplankton pigment, chlorophyll- a (Chla; measured in mg m-3). Here, global Chla data for 2013 are evaluated within the context of the 16-year continuous record provided through the combined observations of SeaWiFS (1997-2010) and MODIS on Aqua (MODISA; 2002-present). Ocean color measurements from the recently launched Visible and Infrared Imaging Radiometer Suite (VIIRS; 2011-present) are also considered, but results suggest that the temporal calibration of the VIIRS sensor is not yet sufficiently stable for quantitative global change studies. All MODISA (version 2013.1), SeaWiFS (version 2010.0), and VIIRS (version 2013.1) data presented here were produced by NASA using consistent Chla algorithms.

  14. Mathematics and Global Survival.

    ERIC Educational Resources Information Center

    Schwartz, Richard H.

    This resource was written to provide students with an awareness of critical issues facing the world today. In courses for college students, it can motivate their study of mathematics, teach them how to solve mathematical problems related to current global issues, provide coherence to mathematical studies through a focus on issues of human…

  15. Global Lessons from Siberia.

    ERIC Educational Resources Information Center

    Tucker, Jan L.

    1993-01-01

    Describes a visit by two U.S. social studies educators to schools in Krasnoyarsk, a city in Siberia, Russia. Discusses economic and social changes brought about by the end of the Cold War. Recommends more international and global education for both Russia and the United States. (CFR)

  16. Teaching for Global Understanding.

    ERIC Educational Resources Information Center

    Schaeffler, Walter S.

    1979-01-01

    Explains why global education programs are needed at all educational levels. Reasons include international interdependence, rapid communication, and the likelihood that students will one day travel to a foreign country. Methods should involve mass media, community resources, language study, stress on intercultural sensitivity, and the case study…

  17. Global patterns in litter decomposition: a synthesis.

    NASA Astrophysics Data System (ADS)

    Auch, W. E.; Ross, D. S.

    2007-12-01

    Leaf and coarse woody debris (LCWD) decay catalyzes the biochemical mechanisms of the soil-aboveground interface, and should be an important component of climate change models that address carbon and nitrogen. There is a clear need for the identification of determinant climate or litter chemistry parameters at the global scale. Local and global decay is commonly attributed to litter chemistry and climate, respectively. The objective of this synthesis was to illustrate LCWD decay across a global climate-chemistry continuum and contrast results with a previous assessment via both standard first-order (|k|) decay kinetics and gradient exponent values arranged in order of influence from initial to latter decay stages. Results suggest greater initial LCWD cation concentrations yielded the fastest initial rates of decomposition and most climatic indices appeared relevant at intermediate stages of decay. Elevation and refractory LCWD carbon (i.e. carbon, lignin, and tannins) were inversely correlated with decay, prolonging the process and possibly acting in concert as "end-point" determinants. Furthermore, the initial influence of nitrogen and phosphorus is universal across LCWD-type as well as ecoregion. Climate acts in a transitional role between easily solubilized and late or aromatic substrate decay. Global and continental carbon cycling assumptions and models must acknowledge: i) the influence of LCWD cation and N concentration during initial fragmentation, leaching, and transformation; ii) climate, specifically seasonal temperature averages > evapotranspiration > precipitation, during the interim; and iii) the ever-present influence of seasonality and litter aromatic components. Key Words: Leaf and Coarse Woody Debris (LCWD) decomposition, |k|, first-order kinetics, Carbon Cycle, Global Climate Change (GCC), Actual Evapotranspiration (AET).

  18. Parallel Transitions in IT Outsourcing: Making It Happen

    NASA Astrophysics Data System (ADS)

    Beulen, Erik; Tiwari, Vinay

    Global sourcing of IT services is growing consistently over the last decades. Along with this rapid growth, instances of failures, sore relationships or unsatisfactory performances during IT outsourcing engagements are prevalent and require management attention. Over two-thirds of the problems in these unsuccessful engagements arise due to failed or poor transition. Transition is immediately followed by contract signing and precedes service delivery phase. It sets the tone for the entire relationship and involves handover of outsourced services from either the client's internal IT department or the incumbent service provider. Recently second and third generation outsourcing engagements are coming into existence, with offshoring and multi-sourcing as an integral component of these engagements. Multi-sourcing deals, involving several service providers are emerging and require transition to be implemented in parallel. These developments exacerbate the complexity of transitions due to the presence of multiple service providers and several distributed or offshore locations, thereby further enhancing its bearing on the success of an engagement. What are the Critical Success Factors for parallel transitions? We conducted an initial Delphi study to explore success factors for parallel transitions. The findings highlight the importance of understanding the contractual agreement including transition exit criteria. Also the implementation of a joint steering committee contributes to transition success. All the stakeholders, including representatives of the incumbent service provider(s), should be represented in the steering committee to act responsive. Finally, the findings emphasis the need to manage dependencies between the transitions not limited to time lines and availability of critical resources for knowledge transfer and balancing between business continuity and timely and effective knowledge transfer.

  19. Global Data Toolset (GDT)

    USGS Publications Warehouse

    Cress, Jill J.; Riegle, Jodi L.

    2007-01-01

    According to the United Nations Environment Programme World Conservation Monitoring Centre (UNEP-WCMC) approximately 60 percent of the data contained in the World Database on Protected Areas (WDPA) has missing or incomplete boundary information. As a result, global analyses based on the WDPA can be inaccurate, and professionals responsible for natural resource planning and priority setting must rely on incomplete geospatial data sets. To begin to address this problem the World Data Center for Biodiversity and Ecology, in cooperation with the U. S. Geological Survey (USGS) Rocky Mountain Geographic Science Center (RMGSC), the National Biological Information Infrastructure (NBII), the Global Earth Observation System, and the Inter-American Biodiversity Information Network (IABIN) sponsored a Protected Area (PA) workshop in Asuncion, Paraguay, in November 2007. The primary goal of this workshop was to train representatives from eight South American countries on the use of the Global Data Toolset (GDT) for reviewing and editing PA data. Use of the GDT will allow PA experts to compare their national data to other data sets, including non-governmental organization (NGO) and WCMC data, in order to highlight inaccuracies or gaps in the data, and then to apply any needed edits, especially in the delineation of the PA boundaries. In addition, familiarizing the participants with the web-enabled GDT will allow them to maintain and improve their data after the workshop. Once data edits have been completed the GDT will also allow the country authorities to perform any required review and validation processing. Once validated, the data can be used to update the global WDPA and IABIN databases, which will enhance analysis on global and regional levels.

  20. Volcanoes and global catastrophes

    NASA Technical Reports Server (NTRS)

    Simkin, Tom

    1988-01-01

    The search for a single explanation for global mass extinctions has let to polarization and the controversies that are often fueled by widespread media attention. The historic record shows a roughly linear log-log relation between the frequency of explosive volcanic eruptions and the volume of their products. Eruptions such as Mt. St. Helens 1980 produce on the order of 1 cu km of tephra, destroying life over areas in the 10 to 100 sq km range, and take place, on the average, once or twice a decade. Eruptions producing 10 cu km take place several times a century and, like Krakatau 1883, destroy life over 100 to 1000 sq km areas while producing clear global atmospheric effects. Eruptions producting 10,000 cu km are known from the Quaternary record, and extrapolation from the historic record suggests that they occur perhaps once in 20,000 years, but none has occurred in historic time and little is known of their biologic effects. Even larger eruptions must also exist in the geologic record, but documentation of their volume becomes increasingly difficult as their age increases. The conclusion is inescapable that prehistoric eruptions have produced catastrophes on a global scale: only the magnitude of the associated mortality is in question. Differentiation of large magma chambers is on a time scale of thousands to millions of years, and explosive volcanoes are clearly concentrated in narrow belts near converging plate margins. Volcanism cannot be dismissed as a producer of global catastrophes. Its role in major extinctions is likely to be at least contributory and may well be large. More attention should be paid to global effects of the many huge eruptions in the geologic record that dwarf those known in historic time.