WorldWideScience

Sample records for earth evolution prescription

  1. Toward understanding early Earth evolution: Prescription for approach from terrestrial noble gas and light element records in lunar soils

    OpenAIRE

    Ozima, Minoru; Yin, Qing-Zhu; Podosek, Frank A.; Miura, Yayoi N.

    2008-01-01

    Because of the almost total lack of geological record on the Earth's surface before 4 billion years ago, the history of the Earth during this period is still enigmatic. Here we describe a practical approach to tackle the formidable problems caused by this lack. We propose that examinations of lunar soils for light elements such as He, N, O, Ne, and Ar would shed a new light on this dark age in the Earth's history and resolve three of the most fundamental questions in earth science: the onset ...

  2. The Earth's early evolution.

    Science.gov (United States)

    Bowring, S A; Housh, T

    1995-09-15

    The Archean crust contains direct geochemical information of the Earth's early planetary differentiation. A major outstanding question in the Earth sciences is whether the volume of continental crust today represents nearly all that formed over Earth's history or whether its rates of creation and destruction have been approximately balanced since the Archean. Analysis of neodymium isotopic data from the oldest remnants of Archean crust suggests that crustal recycling is important and that preserved continental crust comprises fragments of crust that escaped recycling. Furthermore, the data suggest that the isotopic evolution of Earth's mantle reflects progressive eradication of primordial heterogeneities related to early differentiation.

  3. Evolution of Earth Like Planets

    Science.gov (United States)

    Monroy-Rodríguez, M. A.; Vega, K. M.

    2017-07-01

    In order to study and explain the evolution of our own planet we have done a review of works related to the evolution of Earth-like planets. From the stage of proto-planet to the loss of its atmosphere. The planetary formation from the gas and dust of the proto-planetary disk, considering the accretion by the process of migration, implies that the material on the proto-planet is very mixed. The newborn planet is hot and compact, it begins its process of stratification by gravity separation forming a super dense nucleus, an intermediate layer of convective mantle and an upper mantle that is less dense, with material that emerges from zones at very high pressure The surface with low pressure, in this process the planet expands and cools. This process also releases gas to the surface, forming the atmosphere, with the gas gravitationally bounded. The most important thing for the life of the planet is the layer of convective mantle, which produces the magnetic field, when it stops the magnetic field disappears, as well as the rings of van allen and the solar wind evaporates the atmosphere, accelerating the evolution and cooling of the planet. In a natural cycle of cataclysms and mass extinctions, the solar system crosses the galactic disk every 30 million years or so, the increase in the meteorite fall triggers the volcanic activity and the increase in the release of CO2 into the atmosphere reaching critical levels (4000 billion tons) leads us to an extinction by overheating that last 100 000 years, the time it takes CO2 to sediment to the ocean floor. Human activity will lead us to reach critical levels of CO2 in approximately 300 years.

  4. Interplay between solid Earth and biological evolution

    Science.gov (United States)

    Höning, Dennis; Spohn, Tilman

    2017-04-01

    Major shifts in Earth's evolution led to progressive adaptations of the biosphere. Particularly the emergence of continents permitted efficient use of solar energy. However, the widespread evolution of the biosphere fed back to the Earth system, often argued as a cause for the great oxidation event or as an important component in stabilizing Earth's climate. Furthermore, biologically enhanced weathering rates alter the flux of sediments in subduction zones, establishing a potential link to the deep interior. Stably bound water within subducting sediments not only enhances partial melting but further affects the mantle rheology. The mantle responds by enhancing its rates of convection, water outgassing, and subduction. How crucial is the emergence and evolution of life on Earth to these processes, and how would Earth have been evolved without the emergence of life? We here discuss concepts and present models addressing these questions and discuss the biosphere as a major component in evolving Earth system feedback cycles.

  5. Virtual Exploration of Earth's Evolution

    Science.gov (United States)

    Anbar, A. D.; Bruce, G.; Semken, S. C.; Summons, R. E.; Buxner, S.; Horodyskyj, L.; Kotrc, B.; Swann, J.; Klug Boonstra, S. L.; Oliver, C.

    2014-12-01

    Traditional introductory STEM courses often reinforce misconceptions because the large scale of many classes forces a structured, lecture-centric model of teaching that emphasizes delivery of facts rather than exploration, inquiry, and scientific reasoning. This problem is especially acute in teaching about the co-evolution of Earth and life, where classroom learning and textbook teaching are far removed from the immersive and affective aspects of field-based science, and where the challenges of taking large numbers of students into the field make it difficult to expose them to the complex context of the geologic record. We are exploring the potential of digital technologies and online delivery to address this challenge, using immersive and engaging virtual environments that are more like games than like lectures, grounded in active learning, and deliverable at scale via the internet. The goal is to invert the traditional lecture-centric paradigm by placing lectures at the periphery and inquiry-driven, integrative virtual investigations at the center, and to do so at scale. To this end, we are applying a technology platform we devised, supported by NASA and the NSF, that integrates a variety of digital media in a format that we call an immersive virtual field trip (iVFT). In iVFTs, students engage directly with virtual representations of real field sites, with which they interact non-linearly at a variety of scales via game-like exploration while guided by an adaptive tutoring system. This platform has already been used to develop pilot iVFTs useful in teaching anthropology, archeology, ecology, and geoscience. With support the Howard Hughes Medical Institute, we are now developing and evaluating a coherent suite of ~ 12 iVFTs that span the sweep of life's history on Earth, from the 3.8 Ga metasediments of West Greenland to ancient hominid sites in East Africa. These iVFTs will teach fundamental principles of geology and practices of scientific inquiry, and expose

  6. Evolution of the Earth-Moon system

    Science.gov (United States)

    Touma, Jihad; Wisdom, Jack

    1994-01-01

    The tidal evolution of the Earth-Moon system is reexamined. Several models of tidal friction are first compared in an averaged Hamiltonian formulation of the dynamics. With one of these models, full integrations of the tidally evolving Earth-Moon system are carried out in the complete, fully interacting, and chaotically evolving planetary system. Classic results on the history of the lunar orbit are confirmed by our more general model. A detailed history of the obliquity of the Earth which takes into account the evolving lunar orbit is presented.

  7. Life and the evolution of Earth's atmosphere.

    Science.gov (United States)

    Kasting, James F; Siefert, Janet L

    2002-05-10

    Harvesting light to produce energy and oxygen (photosynthesis) is the signature of all land plants. This ability was co-opted from a precocious and ancient form of life known as cyanobacteria. Today these bacteria, as well as microscopic algae, supply oxygen to the atmosphere and churn out fixed nitrogen in Earth's vast oceans. Microorganisms may also have played a major role in atmosphere evolution before the rise of oxygen. Under the more dim light of a young sun cooler than today's, certain groups of anaerobic bacteria may have been pumping out large amounts of methane, thereby keeping the early climate warm and inviting. The evolution of Earth's atmosphere is linked tightly to the evolution of its biota.

  8. Factors Influencing the Earth's Magnetic Field Evolution

    CERN Document Server

    Kurazhkovskii, A Yu; Klain, B I

    2008-01-01

    The relationship between the behavior of an ancient geomagnetic field characteristics (paleointensity and frequency of inversions) and cyclic recurrence of endogenic and cosmogeneous processes which are conceivably connected with radial mantle heat transmission and the Earth rotation speed has been studied. It is shown that endogenic processes affect the behavior of the paleointensity and frequency of inversions. Large basalt effusions identified with plumes are accompanied by the changes in paleointensity (by 30-40)% and the frequency of inversions. Characteristic time intervals of paleointensity variations caused by the formation of plumes makes up 10-20 Ma. The paleointensity varies (by 15-30)% according to phases of the riftogenesis activization and tension - compression cycles. The dependence of geomagnetic field behavior on changes of the Earth rotation speed which occurred as a result of the Earth - Moon - Sun system evolution has been analyzed. Thus, in accordance with phases of the Earth - Moon dista...

  9. Earth System Oxygenation: Toward an Integrated Theory of Earth Evolution

    Science.gov (United States)

    Anbar, A. D.

    2015-12-01

    The cause of the progressive oxygenation of Earth's biosphere remains poorly understood. The problem is bounded by the interplay of three irreversible, secular changes: the escape of H to space, which makes the planet more oxidized; the evolution of photoautotrophy - which converts solar energy into redox disequilbrium - and related metabolisms; and the cooling of the planet, which affects the exchange of material between Earth's reduced interior and relatively oxidized surface through a variety of processes. The first of these changes is quantitatively considered elsewhere, and is connected to the other two because H escape depends on atmospheric H2 and CH4 contents. The second of these changes is an area of vigorous research, particularly over the past decade. Important work included efforts to constrain the timing of key evolutionary events using organic geochemical and genomic records, and to understand the timing and tempo of environmental oxidation, particularly preceding the "Great Oxidation Event" (GOE) at ~2.4 Ga. As the community sorts through various debates, evidence is accumulating that the pre-GOE period was a dynamic era of transient "whiffs" of oxidation, most likely due to small amounts of biogenic O2 that appeared as early as ~3.0 Ga. The implication is that O2 sinks generally overwhelmed substantial O2 sources through the first half of Earth history, and that a decrease in sink strength and/or increase in source strength could have resulted in increasing instability of trace pO2 in the runup to the GOE. The most likely sinks are coupled to reductants in Earth's interior, which leads us to the third major change—secular cooling of the planet. It is almost certain that this cooling led to changes in mantle dynamics, rates of plate motion, and melting behaviors, which in turn affected volcanism, crust composition, hydrothermal and metamorphic alteration, ocean nutrient budgets, and recycling at subduction zones. These factors have all been

  10. [The evolution of principal drugs in prescription compatibility].

    Science.gov (United States)

    Yuan, Bing; Shi, Dong-ping

    2009-01-01

    The principal drugs of principal, adjuvant, auxiliary and conductant compatiblity in prescriptions recorded in the ancient literatures had different meaning and quantities. According to the current literatures, Zhuangzi Xu Wugui took the one can cure diseases as the principal drug; The principal, adjuvant, auxiliary and conductant drugs in Shennong Bencao Jing (Shennong's Classic of Materia Medica) can be used to differentiate the good and bad of drugs; Yaoxing Lun (Treatise on medicinal property) of Zheng quan (Tang dynasty) stipulated some drugs as principal drugs; Zazhu Bencao of Jiang Xiaowan (Tang dynasty) took the one can cure yin diseases as the principal drugs; Yixue Qiyuan (the origination of medicine) of Zhang Yuansu (Jin dynasty) took the one of maximum dosage as principal drugs; Piwei Lun (Treatise on Spleen and Stomach) of LI gao (Jin dynasty) took the powerful one as the principal drug; The principal drugs in Yi Lun (medicine treatise) of Wang Kentang (Ming dynasty) changed according to different ages. The quantities of principal drugs can had two and three ingredients even took one prescription as principal drug instead of one ingredient.

  11. Atmospheric nitrogen evolution on Earth and Venus

    Science.gov (United States)

    Wordsworth, R. D.

    2016-08-01

    Nitrogen is the most common element in Earth's atmosphere and also appears to be present in significant amounts in the mantle. However, its long-term cycling between these two reservoirs remains poorly understood. Here a range of biotic and abiotic mechanisms are evaluated that could have caused nitrogen exchange between Earth's surface and interior over time. In the Archean, biological nitrogen fixation was likely strongly limited by nutrient and/or electron acceptor constraints. Abiotic fixation of dinitrogen becomes efficient in strongly reducing atmospheres, but only once temperatures exceed around 1000 K. Hence if atmospheric N2 levels really were as low as they are today 3.0-3.5 Ga, the bulk of Earth's mantle nitrogen must have been emplaced in the Hadean, most likely at a time when the surface was molten. The elevated atmospheric N content on Venus compared to Earth can be explained abiotically by a water loss redox pump mechanism, where oxygen liberated from H2O photolysis and subsequent H loss to space oxidises the mantle, causing enhanced outgassing of nitrogen. This mechanism has implications for understanding the partitioning of other Venusian volatiles and atmospheric evolution on exoplanets.

  12. A Prescription for Galaxy Biasing Evolution as a Nuisance Parameter

    CERN Document Server

    Clerkin, L; Lahav, O; Abdalla, F B; Gaztanaga, E

    2014-01-01

    There is currently no consistent approach to modelling galaxy bias evolution in cosmological inference. This lack of a common standard makes the rigorous comparison or combination of probes difficult. We show that the choice of biasing model has a significant impact on cosmological parameter constraints for a survey such as the Dark Energy Survey (DES), considering the 2-point correlations of galaxies in five tomographic redshift bins. We find that modelling galaxy bias with a free biasing parameter per redshift bin gives a Figure of Merit (FoM) for Dark Energy equation of state parameters $w_0, w_a$ smaller by a factor of 10 than if a constant bias is assumed. An incorrect bias model will also cause a shift in measured values of cosmological parameters. Motivated by these points and focusing on the redshift evolution of linear bias, we propose the use of a generalised galaxy bias which encompasses a range of bias models from theory, observations and simulations, $b(z) = c + (b_0 - c)/D(z)^\\alpha$, where $c, ...

  13. A prescription for galaxy biasing evolution as a nuisance parameter

    Science.gov (United States)

    Clerkin, L.; Kirk, D.; Lahav, O.; Abdalla, F. B.; Gaztañaga, E.

    2015-04-01

    There is currently no consistent approach to modelling galaxy bias evolution in cosmological inference. This lack of a common standard makes the rigorous comparison or combination of probes difficult. We show that the choice of biasing model has a significant impact on cosmological parameter constraints for a survey such as the Dark Energy Survey (DES), considering the two-point correlations of galaxies in five tomographic redshift bins. We find that modelling galaxy bias with a free biasing parameter per redshift bin gives a Figure of Merit (FoM) for dark energy equation of state parameters w0, wa smaller by a factor of 10 than if a constant bias is assumed. An incorrect bias model will also cause a shift in measured values of cosmological parameters. Motivated by these points and focusing on the redshift evolution of linear bias, we propose the use of a generalized galaxy bias which encompasses a range of bias models from theory, observations and simulations, b(z) = c + (b0 - c)/D(z)α, where parameters c, b0 and α depend on galaxy properties such as halo mass. For a DES-like galaxy survey, we find that this model gives an unbiased estimate of w0, wa with the same number or fewer nuisance parameters and a higher FoM than a simple b(z) model allowed to vary in z-bins. We show how the parameters of this model are correlated with cosmological parameters. We fit a range of bias models to two recent data sets, and conclude that this generalized parametrization is a sensible benchmark expression of galaxy bias on large scales.

  14. A prescription and fast code for the long-term evolution of star clusters II: unbalanced and core evolution

    CERN Document Server

    Gieles, Mark; Lamers, Henny; Baumgardt, Holger

    2013-01-01

    We introduce version two of the fast star cluster evolution code Evolve Me A Cluster of StarS (EMACSS). The first version (Alexander & Gieles) assumed that cluster evolution is balanced for the majority of the life-cycle, meaning that the rate of energy generation in the core of the cluster equals the diffusion rate of energy by two-body relaxation, which makes the code suitable for modelling clusters in weak tidal fields. In this new version we extend the model to include an unbalanced phase of evolution to describe the pre-collapse evolution and the accompanying escape rate such that clusters in strong tidal fields can also be modelled. We also add a prescription for the evolution of the core radius and density and a related cluster concentration parameter. The model simultaneously solves a series of first-order ordinary differential equations for the rate of change of the core radius, half-mass radius and the number of member stars N. About two thousand integration steps in time are required to solve f...

  15. The Evolution of the Earth's Magnetic Field.

    Science.gov (United States)

    Bloxham, Jeremy; Gubbins, David

    1989-01-01

    Describes the change of earth's magnetic field at the boundary between the outer core and the mantle. Measurement techniques used during the last 300 years are considered. Discusses the theories and research for explaining the field change. (YP)

  16. Atmospheric nitrogen evolution on Earth and Venus

    CERN Document Server

    Wordsworth, R D

    2016-01-01

    Nitrogen is the most common element in Earth's atmosphere and also appears to be present in significant amounts in the mantle. However, its long-term cycling between these two reservoirs remains poorly understood. Here a range of biotic and abiotic mechanisms are evaluated that could have caused nitrogen exchange between Earth's surface and interior over time. In the Archean, biological nitrogen fixation was likely strongly limited by nutrient and/or electron acceptor constraints. Abiotic fixation of dinitrogen becomes efficient in strongly reducing atmospheres, but only once temperatures exceed around 1000 K. Hence if atmospheric N2 levels really were as low as they are today 3.0 - 3.5 Ga, the bulk of Earth's mantle nitrogen must have been emplaced in the Hadean, most likely at a time when the surface was molten. The elevated atmospheric N content on Venus compared to Earth can be explained abiotically by a water loss redox pump mechanism, where oxygen liberated from H2O photolysis and subsequent H loss to s...

  17. Factors Influencing the Earth's Magnetic Field Evolution

    OpenAIRE

    Kurazhkovskii, A. Yu.; Kurazhkovskaya, N. A.; Klain, B. I.

    2008-01-01

    The relationship between the behavior of an ancient geomagnetic field characteristics (paleointensity and frequency of inversions) and cyclic recurrence of endogenic and cosmogeneous processes which are conceivably connected with radial mantle heat transmission and the Earth rotation speed has been studied. It is shown that endogenic processes affect the behavior of the paleointensity and frequency of inversions. Large basalt effusions identified with plumes are accompanied by the changes in ...

  18. Origin and evolution of the earth-moon system.

    Science.gov (United States)

    Alfven, H.; Arrhenius, G.

    1972-01-01

    The general problem of formation of secondary bodies around a central body is studied, and comparison is made with other satellite systems (Jupiter, Saturn, Uranus). The normal satellite systems of Neptune and the earth are reconstructed. The capture theory, the tidal evolution of the lunar orbit, destruction of a normal satellite system, asteroids and the earth-moon system, and accretion and heat structure of the moon are discussed. It is concluded that the moon originated as a planet accreted in a jet stream near the orbit of the earth, and was probably captured in a retrograde orbit.

  19. Hydrogenation of iron in the early stage of Earth's evolution

    Science.gov (United States)

    Iizuka-Oku, Riko; Yagi, Takehiko; Gotou, Hirotada; Okuchi, Takuo; Hattori, Takanori; Sano-Furukawa, Asami

    2017-01-01

    Density of the Earth's core is lower than that of pure iron and the light element(s) in the core is a long-standing problem. Hydrogen is the most abundant element in the solar system and thus one of the important candidates. However, the dissolution process of hydrogen into iron remained unclear. Here we carry out high-pressure and high-temperature in situ neutron diffraction experiments and clarify that when the mixture of iron and hydrous minerals are heated, iron is hydrogenized soon after the hydrous mineral is dehydrated. This implies that early in the Earth's evolution, as the accumulated primordial material became hotter, the dissolution of hydrogen into iron occurred before any other materials melted. This suggests that hydrogen is likely the first light element dissolved into iron during the Earth's evolution and it may affect the behaviour of the other light elements in the later processes.

  20. Atmospheres and evolution. [of microbial life on earth

    Science.gov (United States)

    Margulis, L.; Lovelock, J. E.

    1981-01-01

    Studies concerning the regulation of the earth atmosphere and the relation of atmospheric changes to the evolution of microbial life are reviewed. The improbable nature of the composition of the earth atmosphere in light of the atmospheric compositions of Mars and Venus and equilibrium considerations is pointed out, and evidence for the existence of microbial (procaryotic) life on earth as far back as 3.5 billion years ago is presented. The emergence of eucaryotic life in the Phanerozoic due to evolving symbioses between different procaryotic species is discussed with examples given of present-day symbiotic relationships between bacteria and eucaryotes. The idea that atmospheric gases are kept in balance mainly by the actions of bacterial cells is then considered, and it is argued that species diversity is necessary for the maintenance and origin of life on earth in its present form.

  1. Protostellar Disk Evolution Over Million-Year Timescales with a Prescription for Magnetized Turbulence

    CERN Document Server

    Landry, Russell; Turner, Neal J; Abram, Greg

    2013-01-01

    Magnetorotational instability (MRI) is the most promising mechanism behind accretion in low-mass protostellar disks. Here we present the first analysis of the global structure and evolution of non-ideal MRI-driven T-Tauri disks on million-year timescales. We accomplish this in a 1+1D simulation by calculating magnetic diffusivities and utilizing turbulence activity criteria to determine thermal structure and accretion rate without resorting to a 3-D magnetohydrodynamical (MHD) simulation. Our major findings are as follows. First, even for modest surface densities of just a few times the minimum-mass solar nebula, the dead zone encompasses the giant planet-forming region, preserving any compositional gradients. Second, the surface density of the active layer is nearly constant in time at roughly 10 g/cm2, which we use to derive a simple prescription for viscous heating in MRI-active disks for those who wish to avoid detailed MHD computations. Furthermore, unlike a standard disk with constant-alpha viscosity, t...

  2. Carbonitriding reactions of diatomaceous earth: phase evolution and reaction mechanisms

    Directory of Open Access Journals (Sweden)

    BRANKO MATOVIC

    2006-06-01

    Full Text Available The possibility of using diatomaceous earth as Si precursor for low temperature synthesis of non-oxide powders by carbothermal reduction-nitridation was studied. It was found that carbonitriding reactions produce phases of the Si–Al–O–N system. Already at 1300 °C, nanosized, non-oxide powders were obtained. The comparatively low reaction temperatures is attributred to the nano-porous nature of the raw material. The evolution of crystalline phases proceeded via many intermediate stages. The powders were characterized by X-ray and SEM investigations. The results showed that diatomaceous earth can be a very effective source for obtaining non-oxide powders.

  3. The Role and Evolution of NASA's Earth Science Data Systems

    Science.gov (United States)

    Ramapriyan, H. K.

    2015-01-01

    One of the three strategic goals of NASA is to Advance understanding of Earth and develop technologies to improve the quality of life on our home planet (NASA strategic plan 2014). NASA's Earth Science Data System (ESDS) Program directly supports this goal. NASA has been launching satellites for civilian Earth observations for over 40 years, and collecting data from various types of instruments. Especially since 1990, with the start of the Earth Observing System (EOS) Program, which was a part of the Mission to Planet Earth, the observations have been significantly more extensive in their volumes, variety and velocity. Frequent, global observations are made in support of Earth system science. An open data policy has been in effect since 1990, with no period of exclusive access and non-discriminatory access to data, free of charge. NASA currently holds nearly 10 petabytes of Earth science data including satellite, air-borne, and ground-based measurements and derived geophysical parameter products in digital form. Millions of users around the world are using NASA data for Earth science research and applications. In 2014, over a billion data files were downloaded by users from NASAs EOS Data and Information System (EOSDIS), a system with 12 Distributed Active Archive Centers (DAACs) across the U. S. As a core component of the ESDS Program, EOSDIS has been operating since 1994, and has been evolving continuously with advances in information technology. The ESDS Program influences as well as benefits from advances in Earth Science Informatics. The presentation will provide an overview of the role and evolution of NASAs ESDS Program.

  4. Review, Intelligence and Development of Rare Earths during Biological Evolution

    Institute of Scientific and Technical Information of China (English)

    Qiu Guanming; Li Wei; Zhang Ming; Li Zhe; Yan Changhao; Li Yourong; Ding Guohui

    2004-01-01

    The relationship between organism and rare earth elements (REE) viewed from evolution was discussed.Some metal ions play key roles in biological functions, however, as the illustration in this article shows, with powerful affinities for oxygen and similar radius, REE can display equally or even more important functions in terms of its biological functions. These attractive characteristics have called more public attention and lead to many applications in agriculture, medicine fields, etc. Furthermore, the article employed the concept of entropy to discuss the dosage effect of REE on organism and the possibility whether REE can become a portion of organism during the evolution.

  5. A Hot Climate on Early Earth: Implications to Biospheric Evolution

    Science.gov (United States)

    Schwartzman, D. W.; Knauth, L. P.

    2009-12-01

    There is now robust evidence for a much warmer climate on the early Earth than now. Both oxygen and silicon isotopes in sedimentary chert and the compelling case for a near constant isotopic oxygen composition of seawater over geologic time support thermophilic surface temperatures until about 1.5-2 billion years ago, aside from a glacial episode in the early Proterozoic. This temperature scenario has important implications to biospheric evolution, including a temperature constraint that held back the emergence of major organismal groups, starting with phototrophs. A geophysiology of biospheric evolution raises the potential of similar coevolutionary relationships of life and its environment on Earth-like planets around Sun-like stars.

  6. Treatment of Parkinson Disease by Meridian Muscle Region Tuina plus Earthly Branches Prescription of Point Selection Along Meridian: A Report of 1 Case

    Institute of Scientific and Technical Information of China (English)

    YE Gui-neng; ZHI Lan-ying; KUAI Le

    2005-01-01

    @@ The treatment of parkinson disease mainly used to depend on medicament. The author treated one patient by meridian muscle region Tuina plus earthly branches prescription of point selection along meridian in the classical time therapeutics,Tuina according to the time and along the meridian, at the end of July, 2003. Now it was reported as follows.

  7. The origin and early evolution of life on earth

    Science.gov (United States)

    Oro, J.; Miller, Stanley L.; Lazcano, Antonio

    1990-01-01

    Results of the studies that have provided insights into the cosmic and primitive earth environments are reviewed with emphasis on those environments in which life is thought to have originated. The evidence bearing on the antiquity of life on the earth and the prebiotic significance of organic compounds found in interstellar clouds and in primitive solar-system bodies such as comets, dark asteroids, and carbonaceous chondrites are assessed. The environmental models of the Hadean and early Archean earth are discussed, as well as the prebiotic formation of organic monomers and polymers essential to life. The processes that may have led to the appearance in the Archean of the first cells are considered, and possible effects of these processes on the early steps of biological evolution are analyzed. The significance of these results to the study of the distribution of life in the universe is evaluated.

  8. Earth's oxygen cycle and the evolution of animal life.

    Science.gov (United States)

    Reinhard, Christopher T; Planavsky, Noah J; Olson, Stephanie L; Lyons, Timothy W; Erwin, Douglas H

    2016-08-09

    The emergence and expansion of complex eukaryotic life on Earth is linked at a basic level to the secular evolution of surface oxygen levels. However, the role that planetary redox evolution has played in controlling the timing of metazoan (animal) emergence and diversification, if any, has been intensely debated. Discussion has gravitated toward threshold levels of environmental free oxygen (O2) necessary for early evolving animals to survive under controlled conditions. However, defining such thresholds in practice is not straightforward, and environmental O2 levels can potentially constrain animal life in ways distinct from threshold O2 tolerance. Herein, we quantitatively explore one aspect of the evolutionary coupling between animal life and Earth's oxygen cycle-the influence of spatial and temporal variability in surface ocean O2 levels on the ecology of early metazoan organisms. Through the application of a series of quantitative biogeochemical models, we find that large spatiotemporal variations in surface ocean O2 levels and pervasive benthic anoxia are expected in a world with much lower atmospheric pO2 than at present, resulting in severe ecological constraints and a challenging evolutionary landscape for early metazoan life. We argue that these effects, when considered in the light of synergistic interactions with other environmental parameters and variable O2 demand throughout an organism's life history, would have resulted in long-term evolutionary and ecological inhibition of animal life on Earth for much of Middle Proterozoic time (∼1.8-0.8 billion years ago).

  9. Impact phenomena as factors in the evolution of the Earth

    Science.gov (United States)

    Grieve, R. A. F.; Parmentier, E. M.

    1984-01-01

    It is estimated that 30 to 200 large impact basins could have been formed on the early Earth. These large impacts may have resulted in extensive volcanism and enhanced endogenic geologic activity over large areas. Initial modelling of the thermal and subsidence history of large terrestrial basins indicates that they created geologic and thermal anomalies which lasted for geologically significant times. The role of large-scale impact in the biological evolution of the Earth has been highlighted by the discovery of siderophile anomalies at the Cretaceous-Tertiary boundary and associated with North American microtektites. Although in neither case has an associated crater been identified, the observations are consistent with the deposition of projectile-contaminated high-speed ejecta from major impact events. Consideration of impact processes reveals a number of mechanisms by which large-scale impact may induce extinctions.

  10. Earth's oxygen cycle and the evolution of animal life

    Science.gov (United States)

    Reinhard, Christopher T.; Planavsky, Noah J.; Olson, Stephanie L.; Lyons, Timothy W.; Erwin, Douglas H.

    2016-08-01

    The emergence and expansion of complex eukaryotic life on Earth is linked at a basic level to the secular evolution of surface oxygen levels. However, the role that planetary redox evolution has played in controlling the timing of metazoan (animal) emergence and diversification, if any, has been intensely debated. Discussion has gravitated toward threshold levels of environmental free oxygen (O2) necessary for early evolving animals to survive under controlled conditions. However, defining such thresholds in practice is not straightforward, and environmental O2 levels can potentially constrain animal life in ways distinct from threshold O2 tolerance. Herein, we quantitatively explore one aspect of the evolutionary coupling between animal life and Earth’s oxygen cycle—the influence of spatial and temporal variability in surface ocean O2 levels on the ecology of early metazoan organisms. Through the application of a series of quantitative biogeochemical models, we find that large spatiotemporal variations in surface ocean O2 levels and pervasive benthic anoxia are expected in a world with much lower atmospheric pO2 than at present, resulting in severe ecological constraints and a challenging evolutionary landscape for early metazoan life. We argue that these effects, when considered in the light of synergistic interactions with other environmental parameters and variable O2 demand throughout an organism’s life history, would have resulted in long-term evolutionary and ecological inhibition of animal life on Earth for much of Middle Proterozoic time (˜1.8-0.8 billion years ago).

  11. Electrons, life and the evolution of Earth's oxygen cycle.

    Science.gov (United States)

    Falkowski, Paul G; Godfrey, Linda V

    2008-08-27

    The biogeochemical cycles of H, C, N, O and S are coupled via biologically catalysed electron transfer (redox) reactions. The metabolic processes responsible for maintaining these cycles evolved over the first ca 2.3 Ga of Earth's history in prokaryotes and, through a sequence of events, led to the production of oxygen via the photobiologically catalysed oxidation of water. However, geochemical evidence suggests that there was a delay of several hundred million years before oxygen accumulated in Earth's atmosphere related to changes in the burial efficiency of organic matter and fundamental alterations in the nitrogen cycle. In the latter case, the presence of free molecular oxygen allowed ammonium to be oxidized to nitrate and subsequently denitrified. The interaction between the oxygen and nitrogen cycles in particular led to a negative feedback, in which increased production of oxygen led to decreased fixed inorganic nitrogen in the oceans. This feedback, which is supported by isotopic analyses of fixed nitrogen in sedimentary rocks from the Late Archaean, continues to the present. However, once sufficient oxygen accumulated in Earth's atmosphere to allow nitrification to out-compete denitrification, a new stable electron 'market' emerged in which oxygenic photosynthesis and aerobic respiration ultimately spread via endosymbiotic events and massive lateral gene transfer to eukaryotic host cells, allowing the evolution of complex (i.e. animal) life forms. The resulting network of electron transfers led a gas composition of Earth's atmosphere that is far from thermodynamic equilibrium (i.e. it is an emergent property), yet is relatively stable on geological time scales. The early coevolution of the C, N and O cycles, and the resulting non-equilibrium gaseous by-products can be used as a guide to search for the presence of life on terrestrial planets outside of our Solar System.

  12. Cell evolution and Earth history: stasis and revolution.

    Science.gov (United States)

    Cavalier-Smith, Thomas

    2006-06-29

    This synthesis has three main parts. The first discusses the overall tree of life and nature of the last common ancestor (cenancestor). I emphasize key steps in cellular evolution important for ordering and timing the major evolutionary innovations in the history of the biosphere, explaining especially the origins of the eukaryote cell and of bacterial flagella and cell envelope novelties. Second, I map the tree onto the fossil record and discuss dates of key events and their biogeochemical impact. Finally, I present a broad synthesis, discussing evidence for a three-phase history of life. The first phase began perhaps ca 3.5 Gyr ago, when the origin of cells and anoxic photosynthesis generated the arguably most primitive prokaryote phylum, Chlorobacteria (= Chloroflexi), the first negibacteria with cells bounded by two acyl ester phospholipid membranes. After this 'chlorobacterial age' of benthic anaerobic evolution protected from UV radiation by mineral grains, two momentous quantum evolutionary episodes of cellular innovation and microbial radiation dramatically transformed the Earth's surface: the glycobacterial revolution initiated an oxygenic 'age of cyanobacteria' and, as the ozone layer grew, the rise of plankton; immensely later, probably as recently as ca 0.9 Gyr ago, the neomuran revolution ushered in the 'age of eukaryotes', Archaebacteria (arguably the youngest bacterial phylum), and morphological complexity. Diversification of glycobacteria ca 2.8 Gyr ago, predominantly inhabiting stratified benthic mats, I suggest caused serial depletion of 13C by ribulose 1,5-bis-phosphate caboxylase/oxygenase (Rubisco) to yield ultralight late Archaean organic carbon formerly attributed to methanogenesis plus methanotrophy. The late origin of archaebacterial methanogenesis ca 720 Myr ago perhaps triggered snowball Earth episodes by slight global warming increasing weathering and reducing CO2 levels, to yield runaway cooling; the origin of anaerobic methane

  13. Subduction History and the Evolution of Earth's Lower Mantle

    Science.gov (United States)

    Bull, Abigail; Shephard, Grace; Torsvik, Trond

    2016-04-01

    Understanding the complex structure, dynamics and evolution of the deep mantle is a fundamental goal in solid Earth geophysics. Close to the core-mantle boundary, seismic images reveal a mantle characterised by (1) higher than average shear wave speeds beneath Asia and encircling the Pacific, consistent with sub ducting lithosphere beneath regions of ancient subduction, and (2) large regions of anomalously low seismic wavespeeds beneath Africa and the Central Pacific. The anomalously slow areas are often referred to as Large Low Shear Velocity Provinces (LLSVPs) due to the reduced velocity of seismic waves passing through them. The origin, composition and long-term evolution of the LLSVPs remain enigmatic. Geochemical inferences of multiple chemical reservoirs at depth, strong seismic contrasts, increased density, and an anticorrelation of shear wave velocity to bulk sound velocity in the anomalous regions imply that heterogeneities in both temperature and composition may be required to explain the seismic observations. Consequently, heterogeneous mantle models place the anomalies into the context of thermochemical piles, characterised by an anomalous component whose intrinsic density is a few percent higher relative to that of the surrounding mantle. Several hypotheses have arisen to explain the LLSVPs in the context of large-scale mantle convection. One end member scenario suggests that the LLSVPs are relatively mobile features over short timescales and thus are strongly affected by supercontinent cycles and Earth's plate motion history. In this scenario, the African LLSVP formed as a result of return flow in the mantle due to circum-Pangean subduction (~240 Ma), contrasting a much older Pacific LLSVP, which may be linked to the Rodinia supercontinent and is implied to have remained largely unchanged since Rodinian breakup (~750-700 Ma). This propounds that Earth's plate motion history plays a controlling role in LLSVP development, suggesting that the location

  14. Jupiter and Planet Earth. [planetary and biological evolution and natural satellites

    Science.gov (United States)

    1975-01-01

    The evolution of Jupiter and Earth are discussed along with their atmospheres, the radiation belts around both planets, natural satellites, the evolution of life, and the Pioneer 10. Educational study projects are also included.

  15. Evolution of the earth's crust: Evidence from comparative planetology

    Science.gov (United States)

    Lowman, P. D., Jr.

    1973-01-01

    Geochemical data and orbital photography from Apollo, Mariner, and Venera missions were combined with terrestrial geologic evidence to study the problem of why the earth has two contrasting types of crust (oceanic and continental). The following outline of terrestrial crustal evolution is proposed. A global crust of intermediate to acidic composition, high in aluminum, was formed by igneous processes early in the earth's history; portions survive in some shield areas as granitic and anorthositic gneisses. This crust was fractured by major impacts and tectonic processes, followed by basaltic eruptions analogous to the lunar maria and the smooth plains of the north hemisphere of Mars. Seafloor spreading and subduction ensued, during which portions of the early continental crust and sediments derived therefrom were thrust under the remaining continental crust. The process is exemplified today in regions such as the Andes/Peru-Chile trench system. Underplating may have been roughly concentric, and the higher radioactive element content of the underplated sialic material could thus eventually cause concentric zones of regional metamorphism and magmatism.

  16. Thermochemical Evolution of Earth's Core with Magnesium Precipitation

    Science.gov (United States)

    O'Rourke, J. G.; Stevenson, D. J.

    2014-12-01

    Vigorous convection within Earth's outer core drives a dynamo that has sustained a global magnetic field for at least 3.5 Gyr. Traditionally, people invoke three energy sources for the dynamo: thermal convection from cooling and freezing, compositional convection from light elements expelled by the growing inner core, and, perhaps, radiogenic heating from potassium-40. New theoretical and experimental work, however, indicates that the thermal and electrical conductivities of the outer core may be as much as three times higher than previously assumed. The implied increase in the adiabatic heat flux casts doubt on the ability of the usual mechanisms to explain the dynamo's longevity. Here, we present a quantitative model of the crystallization of magnesium-bearing minerals from the cooling core—a plausible candidate for the missing power source. Recent diamond-anvil cell experiments suggest that magnesium can partition into core material if thermodynamic equilibrium is achieved at high temperatures (>5000 K). We develop a model for core/mantle differentiation in which most of the core forms from material equilibrated at the base of a magma ocean as Earth slowly grows, but a small portion (~10%) equilibrated at extreme conditions in the aftermath of a giant impact. We calculate the posterior probability distribution for the original concentrations of magnesium and other light elements (chiefly oxygen and silicon) in the core, constrained by partitioning experiments and the observed depletion of siderophile elements in Earth's mantle. We then simulate the thermochemical evolution of cores with plausible compositions and thermal structures from the end of accretion to the present, focusing on the crystallization of a few percent of the initial core as ferropericlase and bridgmanite. Finally, we compute the associated energy release and verify that our final core compositions are consistent with the available seismological data.

  17. Qualified Fitness and Exercise as Professionals and Exercise Prescription: Evolution of the PAR-Q and Canadian Aerobic Fitness Test.

    Science.gov (United States)

    Shephard, Roy J

    2015-04-01

    Traditional approaches to exercise prescription have included a preliminary medical screening followed by exercise tests of varying sophistication. To maximize population involvement, qualified fitness and exercise professionals (QFEPs) have used a self-administered screening questionnaire (the Physical Activity Readiness Questionnaire, PAR-Q) and a simple measure of aerobic performance (the Canadian Aerobic Fitness Test, CAFT). However, problems have arisen in applying the original protocol to those with chronic disease. Recent developments have addressed these issues. Evolution of the PAR-Q and CAFT protocol is reviewed from their origins in 1974 to the current electronic decision tree model of exercise screening and prescription. About a fifth of apparently healthy adults responded positively to the original PAR-Q instrument, thus requiring an often unwarranted referral to a physician. Minor changes of wording did not overcome this problem. However, a consensus process has now developed an electronic decision tree for stratification of exercise risk not only for healthy individuals, but also for those with various types of chronic disease. The new approach to clearance greatly reduces physician referrals and extends the role of QFEPs. The availability of effective screening and simple fitness testing should contribute to the goal of maximizing physical activity in the entire population.

  18. A prescription and fast code for the long-term evolution of star clusters - II. Unbalanced and core evolution

    NARCIS (Netherlands)

    M. Gieles; P.E.R. Alexander; H.J.G.L.M. Lamers; H. Baumgardt

    2013-01-01

    We introduce version two of the fast star cluster evolution code Evolve Me A Cluster of StarS (emacss). The first version (Alexander and Gieles) assumed that cluster evolution is balanced for the majority of the life cycle, meaning that the rate of energy generation in the core of the cluster equals

  19. A prescription and fast code for the long-term evolution of star clusters - II. Unbalanced and core evolution

    NARCIS (Netherlands)

    M. Gieles; P.E.R. Alexander; H.J.G.L.M. Lamers; H. Baumgardt

    2014-01-01

    We introduce version two of the fast star cluster evolution code Evolve Me A Cluster of StarS (emacss). The first version (Alexander and Gieles) assumed that cluster evolution is balanced for the majority of the life cycle, meaning that the rate of energy generation in the core of the cluster equals

  20. Thermal evolution of Earth with magnesium precipitation in the core

    Science.gov (United States)

    O'Rourke, Joseph G.; Korenaga, Jun; Stevenson, David J.

    2017-01-01

    Vigorous convection in Earth's core powers our global magnetic field, which has survived for over three billion years. In this study, we calculate the rate of entropy production available to drive the dynamo throughout geologic time using one-dimensional parameterizations of the evolution of Earth's core and mantle. To prevent a thermal catastrophe in models with realistic Urey ratios, we avoid the conventional scaling for plate tectonics in favor of one featuring reduced convective vigor for hotter mantle. We present multiple simulations that capture the effects of uncertainties in key parameters like the rheology of the lower mantle and the overall thermal budget. Simple scaling laws imply that the heat flow across the core/mantle boundary was elevated by less than a factor of two in the past relative to the present. Another process like the precipitation of magnesium-bearing minerals is therefore required to sustain convection prior to the nucleation of the inner core roughly one billion years ago, especially given the recent, upward revision to the thermal conductivity of the core. Simulations that include precipitation lack a dramatic increase in entropy production associated with the formation of the inner core, complicating attempts to determine its age using paleomagnetic measurements of field intensity. Because mantle dynamics impose strict limits on the amount of heat extracted from the core, we find that the addition of radioactive isotopes like potassium-40 implies less entropy production today and in the past. On terrestrial planets like Venus with more sluggish mantle convection, even precipitation of elements like magnesium may not sustain a dynamo if cooling rates are too slow.

  1. Earth Evolution and Dynamics (Arthur Holmes Medal Lecture)

    Science.gov (United States)

    Torsvik, Trond H.

    2016-04-01

    While physicists are fantasizing about a unified theory that can explain just about everything from subatomic particles (quantum mechanics) to the origin of the Universe (general relativity), Darwin already in 1858 elegantly unified the biological sciences with one grand vision. In the Earth Sciences, the description of the movement and deformation of the Earth's outer layer has evolved from Continental Drift (1912) into Sea-Floor Spreading (1962) and then to the paradigm of Plate Tectonics in the mid-to-late 1960s. Plate Tectonics has been extremely successful in providing a framework for understanding deformation and volcanism at plate boundaries, allowed us to understand how continent motions through time are a natural result of heat escaping from Earth's deep interior, and has granted us the means to conduct earthquake and volcanic hazard assessments and hydrocarbon exploration, which have proven indispensable for modern society. Plate Tectonics is as fundamentally unifying to the Earth Sciences as Darwin's Theory of Evolution is to the Life Sciences, but it is an incomplete theory that lacks a clear explanation of how plate tectonics, mantle convection and mantle plumes interact. Over the past decade, however, we have provided compelling evidence that plumes rise from explicit plume generation zones at the margins of two equatorial and antipodal large low shear-wave velocity provinces (Tuzo and Jason). These thermochemical provinces on the core-mantle boundary have been stable for at least the last 300 million years, possibly the last 540 million years, and their edges are the dominant sources of the plumes that generate large igneous provinces, hotspots and kimberlites. Linking surface and lithospheric processes to the mantle is extremely challenging and is only now becoming feasible due to breakthroughs in the estimation of ancient longitudes before the Cretaceous, greatly improved seismic tomography, recent advances in mineral physics, and new developments

  2. Dynamical Evolution of the Earth-Moon Progenitors - Whence Theia?

    CERN Document Server

    Quarles, Billy

    2014-01-01

    We present integrations of a model Solar System with five terrestrial planets (beginning ~30-50 Myr after the formation of primitive Solar System bodies) in order to determine the preferred regions of parameter space leading to a giant impact that resulted in the formation of the Moon. Our results indicate which choices of semimajor axes and eccentricities for Theia (the proto-Moon) at this epoch can produce a late Giant Impact, assuming that Mercury, Venus, and Mars are near the current orbits. We find that the likely semimajor axis of Theia, at the epoch when our simulations begin, depends on the assumed mass ratio of Earth-Moon progenitors (8/1, 4/1, or 1/1). The low eccentricities of the terrestrial planets are most commonly produced when the progenitors have similar semimajor axes at the epoch when our integrations commence. Additionally, we show that mean motion resonances among the terrestrial planets and perturbations from the giant planets can affect the dynamical evolution of the system leading to a...

  3. The role of rotation on the evolution of dynamo generated magnetic fields in Super Earths

    CERN Document Server

    Zuluaga, Jorge I

    2011-01-01

    Planetary magnetic fields could have a role on the evolution of planetary atmospheres and the required conditions for the emergence and evolution of life (habitability). After briefly review the current efforts to study the evolution of dynamo generated magnetic fields in massive earth-like rocky planets (Super Earths), we take the results from thermal evolution models and updated scaling laws for convection driven magnetodynamos to predict the evolution of the local Rossby number, the basic indicator of core magnetic field geometry and regime. We study the dependence of this property on planetary mass and rotation rate. Previous works have paid Attention only to the evolution of dipolar dominant core magnetic fields assuming rapid rotating planets. Here we extend these results including consistently the effects of rotation on the evolution of planetary magnetic field properties and obtain global constraints to the existence of intense protective magnetic fields in rapidly and slowly rotating Super Earths. We...

  4. Prescription vs. Praxis: The Evolution of Future Temporal Reference in French

    Science.gov (United States)

    Poplack, Shana; Dion, Nathalie

    2009-01-01

    Because many of the forms participating in inherent variability are not attested in the standard language, they are often construed as evidence of change. We test this assumption by confronting the standard, as instantiated by a unique corpus covering five centuries of French grammatical injunctions, with data on the evolution of spontaneous…

  5. Beyond the Paleolithic prescription: incorporating diversity and flexibility in the study of human diet evolution.

    Science.gov (United States)

    Turner, Bethany L; Thompson, Amanda L

    2013-08-01

    Evolutionary paradigms of human health and nutrition center on the evolutionary discordance or "mismatch" model in which human bodies, reflecting adaptations established in the Paleolithic era, are ill-suited to modern industrialized diets, resulting in rapidly increasing rates of chronic metabolic disease. Though this model remains useful, its utility in explaining the evolution of human dietary tendencies is limited. The assumption that human diets are mismatched to the evolved biology of humans implies that the human diet is instinctual or genetically determined and rooted in the Paleolithic era. This review looks at current research indicating that human eating habits are learned primarily through behavioral, social, and physiological mechanisms that start in utero and extend throughout the life course. Adaptations that appear to be strongly genetic likely reflect Neolithic, rather than Paleolithic, adaptations and are significantly influenced by human niche-constructing behavior. Several examples are used to conclude that incorporating a broader understanding of both the evolved mechanisms by which humans learn and imprint eating habits and the reciprocal effects of those habits on physiology would provide useful tools for structuring more lasting nutrition interventions.

  6. THE LONG TIME BEHAVIORS OF NON-AUTONOMOUS EVOLUTION SYSTEM DESCRIBING GEOPHYSICAL FLOW WITHIN THE EARTH

    Institute of Scientific and Technical Information of China (English)

    ZHAO Chunshan; LI Kaitai; HUANG Aixiang

    2002-01-01

    In this paper, the long time behaviors of non-autonomous evolution system describing geophysical flow within the earth are studied. The uniqueness and existence of the solution to the evolution system and the existence of uniform attractor are proven.Moreover, the upper bounds of the uniform attractor's Hausdorff and Fractal dimensions are obtained.

  7. UV SURFACE ENVIRONMENT OF EARTH-LIKE PLANETS ORBITING FGKM STARS THROUGH GEOLOGICAL EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Rugheimer, S.; Sasselov, D. [Harvard Smithsonian Center for Astrophysics, 60 Garden st., 02138 MA Cambridge (United States); Segura, A. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, México (Mexico); Kaltenegger, L., E-mail: srugheimer@cfa.harvard.edu [Carl Sagan Institute, Cornell University, Ithaca, NY 14853 (United States)

    2015-06-10

    The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars in the circumstellar Habitable Zone for Earth through its geological evolution. We explore four different types of atmospheres corresponding to an early-Earth atmosphere at 3.9 Gyr ago and three atmospheres covering the rise of oxygen to present-day levels at 2.0 Gyr ago, 0.8 Gyr ago, and modern Earth. In addition to calculating the UV flux on the surface of the planet, we model the biologically effective irradiance, using DNA damage as a proxy for biological damage. We find that a pre-biotic Earth (3.9 Gyr ago) orbiting an F0V star receives 6 times the biologically effective radiation as around the early Sun and 3520 times the modern Earth–Sun levels. A pre-biotic Earth orbiting GJ 581 (M3.5 V) receives 300 times less biologically effective radiation, about 2 times modern Earth–Sun levels. The UV fluxes calculated here provide a grid of model UV environments during the evolution of an Earth-like planet orbiting a range of stars. These models can be used as inputs into photo-biological experiments and for pre-biotic chemistry and early life evolution experiments.

  8. Evolution of the Oxidation State of the Earth's Mantle

    Science.gov (United States)

    Danielson, L. R.; Righter, K.; Keller, L.; Christoffersen, E.; Rahman, Z.

    2015-01-01

    The oxidation state of the Earth's mantle during formation remains an unresolved question, whether it was constant throughout planetary accretion, transitioned from reduced to oxidized, or from oxidized to reduced. We investigate the stability of Fe3(+) at depth, in order to constrain processes (water, late accretion, dissociation of FeO) which may reduce or oxidize the Earth's mantle. In our previous experiments on shergottite compositions, variable fO2, T, and P less than 4 GPa, Fe3(+)/sigma Fe decreased slightly with increasing P, similar to terrestrial basalt. For oxidizing experiments less than 7GPa, Fe3(+)/sigma Fe decreased as well, but it's unclear from previous modelling whether the deeper mantle could retain significant Fe3(+). Our current experiments expand our pressure range deeper into the Earth's mantle and focus on compositions and conditions relevant to the early Earth. Preliminary multi-anvil experiments with Knippa basalt as the starting composition were conducted at 5-7 GPa and 1800 C, using a molybdenum capsule to set the fO2 near IW, by buffering with Mo-MoO3. TEM and EELS analyses revealed the run products quenched to polycrystalline phases, with the major phase pyroxene containing approximately equal to Fe3(+)/2(+). Experiments are underway to produce glassy samples that can be measured by EELS and XANES, and are conducted at higher pressures.

  9. Core cooling by subsolidus mantle convection. [thermal evolution model of earth

    Science.gov (United States)

    Schubert, G.; Cassen, P.; Young, R. E.

    1979-01-01

    Although vigorous mantle convection early in the thermal history of the earth is shown to be capable of removing several times the latent heat content of the core, a thermal evolution model of the earth in which the core does not solidify can be constructed. The large amount of energy removed from the model earth's core by mantle convection is supplied by the internal energy of the core which is assumed to cool from an initial high temperature given by the silicate melting temperature at the core-mantle boundary. For the smaller terrestrial planets, the iron and silicate melting temperatures at the core-mantle boundaries are more comparable than for the earth; the models incorporate temperature-dependent mantle viscosity and radiogenic heat sources in the mantle. The earth models are constrained by the present surface heat flux and mantle viscosity and internal heat sources produce only about 55% of the earth model's present surface heat flow.

  10. Coupled orbital-thermal evolution of the early Earth-Moon system with a fast-spinning Earth

    Science.gov (United States)

    Tian, ZhenLiang; Wisdom, Jack; Elkins-Tanton, Linda

    2017-01-01

    Several new scenarios of the Moon-forming giant impact have been proposed to reconcile the giant impact theory with the recent recognition of the volatile and refractory isotopic similarities between Moon and Earth. Two scenarios leave the post-impact Earth spinning much faster than what is inferred from the present Earth-Moon system's angular momentum. The evection resonance has been proposed to drain the excess angular momentum, but the lunar orbit stays at high orbital eccentricities for long periods in the resonance, which would cause large tidal heating in the Moon. A limit cycle related to the evection resonance has also been suggested as an alternative mechanism to reduce the angular momentum, which keeps the lunar orbit at much lower eccentricities, and operates in a wider range of parameters. In this study we use a coupled thermal-orbital model to determine the effect of the change of the Moon's thermal state on the Earth-Moon system's dynamical history. The evection resonance no longer drains angular momentum from the Earth-Moon system since the system rapidly exits the resonance. Whereas the limit cycle works robustly to drain as much angular momentum as in the non-thermally-coupled model, though the Moon's tidal properties change throughout the evolution.

  11. Evolution of the Early Earth and Its Biosphere

    Science.gov (United States)

    DesMarais, David J.

    1996-01-01

    The history of life on Earth is a rich tapestry of adaptation and innovation which was shaped, at least in part, by the changing surface environment of our planet. To the extent that all rocky planets have followed similar evolutionary paths, studies of our own biosphere can guide us in our search for extraterrestrial life. Understanding the nature, timing, and causes of long-term changes in the global environment is a key objective.

  12. The role of Jupiter in driving Earth's orbital evolution

    CERN Document Server

    Horner, Jonathan; Koch, F Elliot

    2014-01-01

    In coming years, the first truly Earth-like planets will be discovered orbiting other stars, and the search for signs of life on these worlds will begin. However, such observations will be hugely time-consuming and costly, and so it will be important to determine which of those planets represent the best prospects for life elsewhere. One of the key factors in such a decision will be the climate variability of the planet in question - too chaotic a climate might render a planet less promising as a target for our initial search for life elsewhere. On the Earth, the climate of the last few million years has been dominated by a series of glacial and interglacial periods, driven by periodic variations in the Earth's orbital elements and axial tilt. These Milankovitch cycles are driven by the gravitational influence of the other planets, and as such are strongly dependent on the architecture of the Solar system. Here, we present the first results of a study investigating the influence of the orbit of Jupiter on the...

  13. [Pattern and evolution of the prescription of olanzapine during one year: Results of the cohort study ECOL].

    Science.gov (United States)

    Gasquet, I; Flandre, P; Heurtebize, N; Deal, C; Perrin, E; Chartier, F; Fourrier-Réglat, A

    2009-02-01

    The necessary evidence of new therapies of clinical interest extends beyond clinical trials in a less controlled population and closer to clinical practice justified since several years the need of conducting observational, noninterventional studies. Observational studies must include epidemiological (quantitative observational) data to define prevalence and natural history of the target conditions. Moreover, pharmacological interventions in "naturalistic" patients populations, selected by clinicians as per clinical judgment within the scope of the target disease will allow to generate data to complement clinical trials. Clinical trials designed to show robust data on efficacy and tolerability particularly during registration trials must be complemented by robust observational research to confirm and better describe clinical effectiveness in the target population. A noninterventional, observational trial is a study where the medicinal product(s) is (are) prescribed in the usual manner in accordance with the terms of the marketing authorization. The assignment of the patient to a particular therapeutic strategy is not decided in advance by a trial protocol but falls within current practice and the prescription of the medicine is clearly separated from the decision to include the patient in the study. No additional diagnosis or monitoring procedures shall be applied to the patients and epidemiological methods shall be used for the analysis of collected data. Olanzapine is a new antipsychotic therapy registered in Europe for the treatment of schizophrenia since 1996. The primary objective of this observational research was to study the evolution of the olanzapine dosage under naturalistic settings. Secondary objectives included patients characteristics, severity of disease, therapeutic evolution and coprescriptions, in a patient's cohort, suffering from schizophrenia, adult patients, diagnosis based on ICD-10; patients were followed during a total of 12 months. The

  14. The Sensitivity of Earth's Climate History To Changes In The Rates of Biological And Geological Evolution

    Science.gov (United States)

    Waltham, D.

    2014-12-01

    The faint young Sun paradox (early Earth had surface liquid water despite solar luminosity 70% of the modern value) implies that our planet's albedo has increased through time and/or greenhouse warming has fallen. The obvious explanation is that negative feedback processes stabilized temperatures. However, the limited temperature data available does not exhibit the expected residual temperature rise and, at least for the Phanerozoic, estimates of climate sensitivity exceed the Planck sensitivity (the zero net-feedback value). The alternate explanation is that biological and geological evolution have tended to cool Earth through time hence countering solar-driven warming. The coincidence that Earth-evolution has roughly cancelled Solar-evolution can then be explained as an emergent property of a complex system (the Gaia hypothesis) or the result of the unavoidable observational bias that Earth's climate history must be compatible with our existence (the anthropic principle). Here, I use a simple climate model to investigate the sensitivity of Earth's climate to changes in the rate of Earth-evolution. Earth-evolution is represented by an effective emissivity which has an intrinsic variation through time (due to continental growth, the evolution of cyanobacteria, orbital fluctuations etc) plus a linear feedback term which enhances emissivity variations. An important feature of this model is a predicted maximum in the radiated-flux versus temperature function. If the increasing solar flux through time had exceeded this value then runaway warming would have occurred. For the best-guess temperature history and climate sensitivity, the Earth has always been within a few percent of this maximum. There is no obvious Gaian explanation for this flux-coincidence but the anthropic principle naturally explains it: If the rate of biological/geological evolution is naturally slow then Earth is a fortunate outlier which evolved just fast enough to avoid solar-induced over

  15. Cell evolution and Earth history: stasis and revolution

    OpenAIRE

    Cavalier-Smith, Thomas

    2006-01-01

    This synthesis has three main parts. The first discusses the overall tree of life and nature of the last common ancestor (cenancestor). I emphasize key steps in cellular evolution important for ordering and timing the major evolutionary innovations in the history of the biosphere, explaining especially the origins of the eukaryote cell and of bacterial flagella and cell envelope novelties. Second, I map the tree onto the fossil record and discuss dates of key events and their biogeochemical i...

  16. The atmospheres of the earth and the other planets: Origin, evolution and composition

    Science.gov (United States)

    Levine, Joel S.

    1988-01-01

    The current understanding of the composition, chemistry, and structure of the atmospheres of the other planets and the origin, early history, and evolution of the earth's atmosphere is reviewed. The information on the atmospheres of the other planets is based on the successful Mariner, Viking, Pioneer, and Voyager missions to these planets. The information on the origin, early history, and evolution of the atmosphere, which is somewhat speculative, is largely based on numerical studies with geochemical and photochemical models.

  17. UV Surface Environment of Earth-like Planets Orbiting FGKM Stars Through Geological Evolution

    CERN Document Server

    Rugheimer, S; Kaltenegger, L; Sasselov, D

    2015-01-01

    The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars at the 1AU equivalent distance for Earth through its geological evolution. We explore four different types of atmospheres corresponding to an early Earth atmosphere at 3.9 Gyr ago and three atmospheres covering the rise of oxygen to present day levels at 2.0 Gyr ago, 0.8 Gyr ago and modern Earth (Following Kaltenegger et al. 2007). In addition to calculating the UV flux on the surface of the planet, we model the biologically effective irradiance, using DNA damage as a proxy for biological damage. We find that a pre-biotic Earth (3.9 Gyr ago) orbiting an F0V star receives 6 times the biologically effective radiation as around the early Sun and 3520 times the modern Earth-Sun levels. A pre-biotic Earth orbiting GJ...

  18. The role of rotation in the evolution of dynamo-generated magnetic fields in Super Earths

    Science.gov (United States)

    Zuluaga, Jorge I.; Cuartas, Pablo A.

    2012-01-01

    Planetary magnetic fields could impact the evolution of planetary atmospheres and have a role in the determination of the required conditions for the emergence and evolution of life (planetary habitability). We study here the role of rotation in the evolution of dynamo-generated magnetic fields in massive Earth-like planets, Super Earths (1-10 M⊕). Using the most recent thermal evolution models of Super Earths (Gaidos, E., Conrad, C.P., Manga, M., Hernlund, J. [2010]. Astrophys. J. 718, 596-609; Tachinami, C., Senshu, H., Ida, S. [2011]. Astrophys. J. 726, 70) and updated scaling laws for convection-driven dynamos, we predict the evolution of the local Rossby number. This quantity is one of the proxies for core magnetic field regime, i.e. non-reversing dipolar, reversing dipolar and multipolar. We study the dependence of the local Rossby number and hence the core magnetic field regime on planetary mass and rotation rate. Previous works have focused only on the evolution of core magnetic fields assuming rapidly rotating planets, i.e. planets in the dipolar regime. In this work we go further, including the effects of rotation in the evolution of planetary magnetic field regime and obtaining global constraints to the existence of intense protective magnetic fields in rapidly and slowly rotating Super Earths. We find that the emergence and continued existence of a protective planetary magnetic field is not only a function of planetary mass but also depend on rotation rate. Low-mass Super Earths ( M ≲ 2 M⊕) develop intense surface magnetic fields but their lifetimes will be limited to 2-4 Gyrs for rotational periods larger than 1-4 days. On the other hand and also in the case of slowly rotating planets, more massive Super Earths ( M ≳ 2 M⊕) have weak magnetic fields but their dipoles will last longer. Finally we analyze tidally locked Super Earths inside and outside the habitable zone of GKM stars. Using the results obtained here we develop a classification of

  19. The Evolution and Future of Earth's Nitrogen Cycle

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene; Glazer, Alexander N.; Falkowski, Paul G.

    2010-01-01

    , the development of new agricultural practices to satisfy a growing global demand for food has drastically disrupted the nitrogen cycle. This has led to extensive eutrophication of fresh waters and coastal zones as well as increased inventories of the potent greenhouse gas nitrous oxide (N2O). Microbial processes......Atmospheric reactions and slow geological processes controlled Earth's earliest nitrogen cycle, and by similar to 2.7 billion years ago, a linked suite of microbial processes evolved to form the modern nitrogen cycle with robust natural feedbacks and controls. Over the past century, however...... will ultimately restore balance to the nitrogen cycle, but the damage done by humans to the nitrogen economy of the planet will persist for decades, possibly centuries, if active intervention and careful management strategies are not initiated....

  20. Evolution of marine and terrestrial geobiodiversity in the history of the earth

    Institute of Scientific and Technical Information of China (English)

    SHEN ShuZhong; ZHOU ZhongHe

    2010-01-01

    @@ People have long been curious about the history of life on the earth-how many different species have existed,when they first occurred, how they evolved over geologic time, and how they reacted to major environmental crises.Although tremendous progresses have been made during the past decades, mysteries in evolution of life abound that remain to be deciphered.changes.

  1. Towards disruptions in Earth observation? New Earth Observation systems and markets evolution: Possible scenarios and impacts

    Science.gov (United States)

    Denis, Gil; Claverie, Alain; Pasco, Xavier; Darnis, Jean-Pierre; de Maupeou, Benoît; Lafaye, Murielle; Morel, Eric

    2017-08-01

    This paper reviews the trends in Earth observation (EO) and the possible impacts on markets of the new initiatives, launched either by existing providers of EO data or by new players, privately funded. After a presentation of the existing models, the paper discusses the new approaches, addressing both commercial and institutional markets. New concepts for the very high resolution markets, in Europe and in the US, are the main focus of this analysis. Two complementary perspectives are summarised: on the one hand, the type of system and its operational performance and, on the other, the related business models, concepts of operation and ownership schemes.

  2. Oxygen Evolution at Nickel Hydroxide Films Co-deposited Light Rare Earth Elements

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Composite nickel hydroxide films were prepared by cathodic co-electrodeposition from metal nitrate solution and characterized by cyclic voltammetry in 1.0 mol/L KOH solution. The codeposited light rare earth elements were lanthanum, cerium, praseodymium and neodymium. The films were analyzed by spectrophotometry and optical transmission. The results of the cyclic voltammetry in 1.0 mol/L KOH solution showed that the current density for oxygen evolution at the film electrode was affected by the co-deposited rare earth metal ions in the film. About 20 mA/cm2 increase of current density for oxygen evolution was found when the film was obtained from the solution with cerium (7% v/v) and nickel (93% v/v) nitrate. The effects of galvanostatic cathodic current density for the film formation on the oxygen evolution at the film electrodes from the alkaline were discussed.

  3. The naked planet Earth: Most essential pre-requisite for the origin and evolution of life

    Directory of Open Access Journals (Sweden)

    S. Maruyama

    2013-03-01

    To satisfy the tight conditions to make the Earth habitable, the formation mechanism of primordial Earth is an important factor. At first, a ‘dry Earth’ must be made through giant impact, followed by magma ocean to float nutrient-enriched primordial continents (anorthosite + KREEP. Late bombardment from asteroid belt supplied water to make 3–5 km thick ocean, and not from icy meteorites from Kuiper belt beyond cool Jupiter. It was essential to meet the above conditions that enabled the Earth as a habitable planet with evolved life forms. The tight constraints that we evaluate for birth and evolution of life on Earth would provide important guidelines for planetary scientists hunting for life in the exo-solar planets.

  4. Tidal evolution of the Moon from a high-obliquity, high-angular-momentum Earth.

    Science.gov (United States)

    Ćuk, Matija; Hamilton, Douglas P; Lock, Simon J; Stewart, Sarah T

    2016-11-17

    In the giant-impact hypothesis for lunar origin, the Moon accreted from an equatorial circum-terrestrial disk; however, the current lunar orbital inclination of five degrees requires a subsequent dynamical process that is still unclear. In addition, the giant-impact theory has been challenged by the Moon's unexpectedly Earth-like isotopic composition. Here we show that tidal dissipation due to lunar obliquity was an important effect during the Moon's tidal evolution, and the lunar inclination in the past must have been very large, defying theoretical explanations. We present a tidal evolution model starting with the Moon in an equatorial orbit around an initially fast-spinning, high-obliquity Earth, which is a probable outcome of giant impacts. Using numerical modelling, we show that the solar perturbations on the Moon's orbit naturally induce a large lunar inclination and remove angular momentum from the Earth-Moon system. Our tidal evolution model supports recent high-angular-momentum, giant-impact scenarios to explain the Moon's isotopic composition and provides a new pathway to reach Earth's climatically favourable low obliquity.

  5. Evolution of the protolunar disk: dynamics, cooling timescale and implantation of volatiles onto the Earth

    CERN Document Server

    Charnoz, Charnoz

    2015-01-01

    It is thought that the Moon accreted from the protolunar disk that was assembled after the last giant impact on Earth. Due to its high temperature, the protolunar disk may act as a thermochemical reactor in which the material is processed before being incorporated into the Moon. Outstanding issues like devolatilisation and istotopic evolution are tied to the disk evolution, however its lifetime, dynamics and thermodynamics are unknown. Here, we numerically explore the long term viscous evolution of the protolunar disk using a one dimensional model where the different phases (vapor and condensed) are vertically stratified. Viscous heating, radiative cooling, phase transitions and gravitational instability are accounted for whereas Moon s accretion is not considered for the moment. The viscosity of the gas, liquid and solid phases dictates the disk evolution. We find that (1) the vapor condenses into liquid in about 10 years, (2) a large fraction of the disk mass flows inward forming a hot and compact liquid di...

  6. On the Tidal Evolution of the Earth-Moon System: A Cosmological Model

    Directory of Open Access Journals (Sweden)

    Arbab A. I.

    2009-01-01

    Full Text Available We have presented a cosmological model for the tidal evolution of the Earth-Moon system. We have found that the expansion of the universe has immense consequences on our local systems. The model can be compared with the present observational data. The close approach problem inflicting the known tidal theory is averted in this model. We have also shown that the astronomical and geological changes of our local systems are of the order of Hubble constant.

  7. On the Tidal Evolution of the Earth-Moon System: A Cosmological Model

    Directory of Open Access Journals (Sweden)

    Arbab A. I.

    2009-01-01

    Full Text Available We have presented a cosmological model for the tidal evolution of the Earth-Moon system. We have found that the expansion of the universe has immense consequences on our local systems. The model can be compared with the present observational data. The close approach problem inflicting the known tidal theory is averted in this model. We have also shown that the astronomical and geological changes of our local systems are of the order of Hubble constant.

  8. Tidal evolution of the Moon from a high-obliquity, high-angular-momentum Earth

    Science.gov (United States)

    Ćuk, Matija; Hamilton, Douglas P.; Lock, Simon J.; Stewart, Sarah T.

    2016-11-01

    In the giant-impact hypothesis for lunar origin, the Moon accreted from an equatorial circum-terrestrial disk; however, the current lunar orbital inclination of five degrees requires a subsequent dynamical process that is still unclear. In addition, the giant-impact theory has been challenged by the Moon’s unexpectedly Earth-like isotopic composition. Here we show that tidal dissipation due to lunar obliquity was an important effect during the Moon’s tidal evolution, and the lunar inclination in the past must have been very large, defying theoretical explanations. We present a tidal evolution model starting with the Moon in an equatorial orbit around an initially fast-spinning, high-obliquity Earth, which is a probable outcome of giant impacts. Using numerical modelling, we show that the solar perturbations on the Moon’s orbit naturally induce a large lunar inclination and remove angular momentum from the Earth-Moon system. Our tidal evolution model supports recent high-angular-momentum, giant-impact scenarios to explain the Moon’s isotopic composition and provides a new pathway to reach Earth’s climatically favourable low obliquity.

  9. Habitability of super-Earth planets around other suns: models including Red Giant Branch evolution.

    Science.gov (United States)

    von Bloh, W; Cuntz, M; Schröder, K-P; Bounama, C; Franck, S

    2009-01-01

    The unexpected diversity of exoplanets includes a growing number of super-Earth planets, i.e., exoplanets with masses of up to several Earth masses and a similar chemical and mineralogical composition as Earth. We present a thermal evolution model for a 10 Earth-mass planet orbiting a star like the Sun. Our model is based on the integrated system approach, which describes the photosynthetic biomass production and takes into account a variety of climatological, biogeochemical, and geodynamical processes. This allows us to identify a so-called photosynthesis-sustaining habitable zone (pHZ), as determined by the limits of biological productivity on the planetary surface. Our model considers solar evolution during the main-sequence stage and along the Red Giant Branch as described by the most recent solar model. We obtain a large set of solutions consistent with the principal possibility of life. The highest likelihood of habitability is found for "water worlds." Only mass-rich water worlds are able to realize pHZ-type habitability beyond the stellar main sequence on the Red Giant Branch.

  10. Teaching about the Early Earth: Evolution of Tectonics, Life, and the Early Atmosphere

    Science.gov (United States)

    Mogk, D. W.; Manduca, C. A.; Kirk, K.; Williams, M. L.

    2007-12-01

    The early history of the Earth is the subject of some of the most exciting and innovative research in the geosciences, drawing evidence from virtually all fields of geoscience and using a variety of approaches that include field, analytical, experimental, and modeling studies. At the same time, the early Earth presents unique opportunities and challenges in geoscience education: how can we best teach "uncertain science" where the evidence is either incomplete or ambiguous? Teaching about early Earth provides a great opportunity to help students understand the nature of scientific evidence, testing, and understanding. To explore the intersection of research and teaching about this enigmatic period of Earth history, a national workshop was convened for experts in early Earth research and undergraduate geoscience education. The workshop was held in April, 2007 at the University of Massachusetts at Amherst as part of the On the Cutting Edge faculty professional development program. The workshop was organized around three scientific themes: evolution of global tectonics, life, and the early atmosphere. The "big scientific questions" at the forefront of current research about the early Earth were explored by keynote speakers and follow-up discussion groups: How did plate tectonics as we know it today evolve? Were there plates in the Hadean Eon? Was the early Earth molten? How rapidly did it cool? When and how did the atmosphere and hydrosphere evolve? How did life originate and evolve? How did all these components interact at the beginning of Earth's history and evolve toward the Earth system we know today? Similar "big questions" in geoscience education were addressed: how to best teach about "deep time;" how to help students make appropriate inferences when geologic evidence is incomplete; how to engage systems thinking and integrate multiple lines of evidence, across many scales of observation (temporal and spatial), and among many disciplines. Workshop participants

  11. Modeling Continental Growth and Mantle Hydration in Earth's Evolution and the Impact of Life

    Science.gov (United States)

    Höning, Dennis; Spohn, Tilman

    2016-04-01

    The evolution of planets with plate tectonics is significantly affected by several intertwined feedback cycles. On Earth, interactions between atmosphere, hydrosphere, biosphere, crust, and interior determine its present day state. We here focus on the feedback cycles including the evolutions of mantle water budget and continental crust, and investigate possible effects of the Earth's biosphere. The first feedback loop includes cycling of water into the mantle at subduction zones and outgassing at volcanic chains and mid-ocean ridges. Water is known to reduce the viscosity of mantle rock, and therefore the speed of mantle convection and plate subduction will increase with the water concentration, eventually enhancing the rates of mantle water regassing and outgassing. A second feedback loop includes the production and erosion of continental crust. Continents are formed above subduction zones, whose total length is determined by the total size of the continents. Furthermore, the total surface area of continental crust determines the amount of eroded sediments per unit time. Subducted sediments affect processes in subduction zones, eventually enhancing the production rate of new continental crust. Both feedback loops affect each other: As a wet mantle increases the speed of subduction, continental production also speeds up. On the other hand, the total length of subduction zones and the rate at which sediments are subducted (both being functions of continental coverage) affect the rate of mantle water regassing. We here present a model that includes both cycles and show how the system develops stable and unstable fixed points in a plane defined by mantle water concentration and surface of continents. We couple these feedback cycles to a parameterized thermal evolution model that reproduces present day observations. We show how Earth has been affected by these feedback cycles during its evolution, and argue that Earth's present day state regarding its mantle water

  12. The Atmospheres of the Terrestrial Planets:Clues to the Origins and Early Evolution of Venus, Earth, and Mars

    Science.gov (United States)

    Baines, Kevin H.; Atreya, Sushil K.; Bullock, Mark A.; Grinspoon, David H,; Mahaffy, Paul; Russell, Christopher T.; Schubert, Gerald; Zahnle, Kevin

    2015-01-01

    We review the current state of knowledge of the origin and early evolution of the three largest terrestrial planets - Venus, Earth, and Mars - setting the stage for the chapters on comparative climatological processes to follow. We summarize current models of planetary formation, as revealed by studies of solid materials from Earth and meteorites from Mars. For Venus, we emphasize the known differences and similarities in planetary bulk properties and composition with Earth and Mars, focusing on key properties indicative of planetary formation and early evolution, particularly of the atmospheres of all three planets. We review the need for future in situ measurements for improving our understanding of the origin and evolution of the atmospheres of our planetary neighbors and Earth, and suggest the accuracies required of such new in situ data. Finally, we discuss the role new measurements of Mars and Venus have in understanding the state and evolution of planets found in the habitable zones of other stars.

  13. THE INFLUENCE OF PRESSURE-DEPENDENT VISCOSITY ON THE THERMAL EVOLUTION OF SUPER-EARTHS

    Energy Technology Data Exchange (ETDEWEB)

    Stamenkovic, Vlada; Noack, Lena; Spohn, Tilman [Institute of Planetology, Westfaelische Wilhelms-Universitaet Muenster, Wilhelm-Klemm-Str. 10, 48149 Muenster (Germany); Breuer, Doris, E-mail: Vlada.Stamenkovic@dlr.de, E-mail: Lena.Noack@dlr.de, E-mail: Doris.Breuer@dlr.de, E-mail: Tilman.Spohn@dlr.de [Institute of Planetary Research, German Aerospace Center DLR, Rutherfordstrasse 2, 12489 Berlin (Germany)

    2012-03-20

    We study the thermal evolution of super-Earths with a one-dimensional (1D) parameterized convection model that has been adopted to account for a strong pressure dependence of the viscosity. A comparison with a 2D spherical convection model shows that the derived parameterization satisfactorily represents the main characteristics of the thermal evolution of massive rocky planets. We find that the pressure dependence of the viscosity strongly influences the thermal evolution of super-Earths-resulting in a highly sluggish convection regime in the lower mantles of those planets. Depending on the effective activation volume and for cooler initial conditions, we observe with growing planetary mass even the formation of a conductive lid above the core-mantle boundary (CMB), a so-called CMB-lid. For initially molten planets our results suggest no CMB-lids but instead a hot lower mantle and core as well as sluggish lower mantle convection. This implies that the initial interior temperatures, especially in the lower mantle, become crucial for the thermal evolution-the thermostat effect suggested to regulate the interior temperatures in terrestrial planets does not work for massive planets if the viscosity is strongly pressure dependent. The sluggish convection and the potential formation of the CMB-lid reduce the convective vigor throughout the mantle, thereby affecting convective stresses, lithospheric thicknesses, and heat fluxes. The pressure dependence of the viscosity may therefore also strongly affect the propensity of plate tectonics, volcanic activity, and the generation of a magnetic field of super-Earths.

  14. The Earth's core formation and development: evidence from evolution of tectonomagmatic processes and paleomagnetic data

    Science.gov (United States)

    Sharkov, E. V.

    2011-12-01

    Many geologists confident that the core provides modern tectonic and magmatic activity on the Earth, which explains our interest in this topic, and vice versa we can use evolution of tectonomagmatic processes throughout the Earth's (and other terrestrial planetary bodies) history for reconstruction of the core formation and evolution. Most researchers, follow to V. Safronov (1972) and A. Ringwood (1979), confident that the Earth has occurred due to accumulation of hypothetical chemically homogeneous planetesimals, composed by chondrite material, ie, as a result of homogeneous accretion. However, this single-stage chondrite model of accretion is inconsistent with fact of cardinal change of tectonomagmatic processes on the terrestrial planets in the middle stages of their development. For example, the critical irreversible change of the Earth's tectonomagmatic evolution occurred in range 2.35-2.0 Ga, when geochemical-enriched Fe-Ti picrites and basalts firstly appeared in large quantities and first geological evidence of plate tectonics showed up (Sharkov, Bogatikov, 2010). We suggest that these changes were linked with ascending of mantle superplumes of the second generation (thermochemical), originated at the the boundary of liquid iron core and silicate mantle, in similar way as the modern plumes. All terrestrial planetary bodies (Earth, Venus, Mars, Mercury, and the Moon) have a similar structure, consist of iron core and silicate envelope, and developed at the same scenario, which provide for drastic irreversible change in character of tectonomagmatic processes at the middle stages of their evolution (Sharkov, Bogatikov, 2009). Such a situation can be realized only in case: (1) the terrestrial planetary bodies originally had heterogeneous structure, and (2) their heating occurred from the top down accompanied by cooling of outer shells. As a result, material of the primordial cores, where enriched material survived, were remained a long time untouched. It

  15. Thermal Evolution of Terrestrial Planets: Earth, Mars, Size, Temperature, Tectonics, and Deep Volatile Cycling

    Science.gov (United States)

    Lenardic, A.; Hero, J.; McGovern, P. J., Jr.

    2014-12-01

    Recent efforts to constrain the thermal evolution of the Martian lithosphere suggest that the ratio of mantle heat production to heat loss, termed the Urey ratio, on Mars may be greater than unity at present (or in Mars' recent past). For comparison, the present day Earth value is 0.33. These estimates fly in the face of conventional wisdom that a smaller planet like Mars should have cooled faster than the Earth - and certainly should not be heating up at present. We perform a sensitivity analysis, using a thermal history modeling approach, to asses the relative effects of changing planetary size, mode of tectonics, and nature of deep volatile cycling (focussing on water). Our results indicate that differences in the nature of volatile cycling (degassing vs regassing over time) can outweigh the effects of size and tectonic mode in determining the thermal state of a planet. Mars models in which degassing dominates can give Urey ratios that exceed unity. Earth models in which regassing dominates over degassing in the later geologic stages of evolution lead to lower Urey ratio values.

  16. Tidal heating of Earth-like exoplanets around M stars: Thermal, magnetic, and orbital evolutions

    CERN Document Server

    Driscoll, Peter

    2015-01-01

    The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low mass M stars whose radiative habitable zone overlaps with the "tidal zone". We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a visco-elastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within $0.07$ AU circularize before 10 G...

  17. The role of Jupiter in driving Earth's orbital evolution: an update

    CERN Document Server

    Horner, J; Waltham, D

    2015-01-01

    In the coming decades, the discovery of the first truly Earth-like exoplanets is anticipated. The characterisation of those planets will play a vital role in determining which are chosen as targets for the search for life beyond the Solar system. One of the many variables that will be considered in that characterisation and selection process is the nature of the potential climatic variability of the exoEarths in question. In our own Solar system, the Earth's long-term climate is driven by several factors - including the modifying influence of life on our atmosphere, and the temporal evolution of Solar luminosity. The gravitational influence of the other planets in our Solar system add an extra complication - driving the Milankovitch cycles that are thought to have caused the on-going series of glacial and interglacial periods that have dominated Earth's climate for the past few million years. Here, we present the results of a large suite of dynamical simulations that investigate the influence of the giant pla...

  18. Strong coronal channelling and interplanetary evolution of a solar storm up to Earth and Mars

    CERN Document Server

    Möstl, Christian; Frahm, Rudy A; Liu, Ying D; Long, David M; Colaninno, Robin C; Reiss, Martin A; Temmer, Manuela; Farrugia, Charles J; Posner, Arik; Dumbović, Mateja; Janvier, Miho; Démoulin, Pascal; Boakes, Peter; Devos, Andy; Kraaikamp, Emil; Mays, Mona L; Vrsnak, Bojan

    2015-01-01

    The severe geomagnetic effects of solar storms or coronal mass ejections (CMEs) are to a large degree determined by their propagation direction with respect to Earth. There is a lack of understanding of the processes that determine their non-radial propagation. Here we present a synthesis of data from seven different space missions of a fast CME, which originated in an active region near the disk centre and, hence, a significant geomagnetic impact was forecasted. However, the CME is demonstrated to be channelled during eruption into a direction + 37+/-10 degree (longitude) away from its source region, leading only to minimal geomagnetic effects. In situ observations near Earth and Mars confirm the channelled CME motion, and are consistent with an ellipse shape of the CME-driven shock provided by the new Ellipse Evolution model, presented here. The results enhance our understanding of CME propagation and shape, which can help to improve space weather forecasts.

  19. Tidal Heating of Earth-like Exoplanets around M Stars: Thermal, Magnetic, and Orbital Evolutions.

    Science.gov (United States)

    Driscoll, P E; Barnes, R

    2015-09-01

    The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low-mass M stars whose radiative habitable zone overlaps with the "tidal zone," where tidal dissipation is expected to be a significant heat source in the interior. We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a viscoelastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within 0.07 AU circularize before 10 Gyr, independent of initial eccentricity. Once circular, these planets cool monotonically and maintain dynamos similar to that of Earth. Planets forced into eccentric orbits can experience a super-cooling of the core and rapid core solidification, inhibiting dynamo action for planets in the habitable zone. We find that tidal heating is insignificant in the habitable zone around 0.45 (or larger) solar-mass stars because tidal dissipation is a stronger function of orbital distance than stellar mass, and the habitable zone is farther from larger stars. Suppression of the planetary magnetic field exposes the atmosphere to stellar wind erosion and the surface to harmful radiation. In addition to weak magnetic fields, massive melt eruption rates and prolonged magma oceans may render eccentric planets in the habitable zone of low-mass stars inhospitable for life.

  20. Evolution of the Earth Observing System (EOS) Data and Information System (EOSDIS)

    Science.gov (United States)

    Ramapriyan, Hampapuram K.; Behnke, Jeanne; Sofinowski, Edwin; Lowe, Dawn; Esfandiari, Mary Ann

    2008-01-01

    One of the strategic goals of the U.S. National Aeronautics and Space Administration (NASA) is to "Develop a balanced overall program of science, exploration, and aeronautics consistent with the redirection of the human spaceflight program to focus on exploration". An important sub-goal of this goal is to "Study Earth from space to advance scientific understanding and meet societal needs." NASA meets this subgoal in partnership with other U.S. agencies and international organizations through its Earth science program. A major component of NASA s Earth science program is the Earth Observing System (EOS). The EOS program was started in 1990 with the primary purpose of modeling global climate change. This program consists of a set of space-borne instruments, science teams, and a data system. The instruments are designed to obtain highly accurate, frequent and global measurements of geophysical properties of land, oceans and atmosphere. The science teams are responsible for designing the instruments as well as scientific algorithms to derive information from the instrument measurements. The data system, called the EOS Data and Information System (EOSDIS), produces data products using those algorithms as well as archives and distributes such products. The first of the EOS instruments were launched in November 1997 on the Japanese satellite called the Tropical Rainfall Measuring Mission (TRMM) and the last, on the U.S. satellite Aura, were launched in July 2004. The instrument science teams have been active since the inception of the program in 1990 and have participation from Brazil, Canada, France, Japan, Netherlands, United Kingdom and U.S. The development of EOSDIS was initiated in 1990, and this data system has been serving the user community since 1994. The purpose of this chapter is to discuss the history and evolution of EOSDIS since its beginnings to the present and indicate how it continues to evolve into the future. this chapter is organized as follows. Sect

  1. Evolution of the Stability Work from Classic Retaining Walls to Mechanically Stabilized Earth Walls

    Directory of Open Access Journals (Sweden)

    Anghel Stanciu

    2008-01-01

    Full Text Available For the consolidation of soil mass and the construction of the stability works for roads infrastructure it was studied the evolution of these kinds of works from classical retaining walls - common concrete retaining walls, to the utilization in our days of the modern and competitive methods - mechanically stabilized earth walls. Like type of execution the variety of the reinforced soil is given by the utilization of different types of reinforcing inclusions (steel strips, geosynthetics, geogrids or facing (precast concrete panels, dry cast modular blocks, metal sheets and plates, gabions, and wrapped sheets of geosynthetics.

  2. Prescriptive unitarity

    Science.gov (United States)

    Bourjaily, Jacob L.; Herrmann, Enrico; Trnka, Jaroslav

    2017-06-01

    We introduce a prescriptive approach to generalized unitarity, resulting in a strictly-diagonal basis of loop integrands with coefficients given by specifically-tailored residues in field theory. We illustrate the power of this strategy in the case of planar, maximally supersymmetric Yang-Mills theory (SYM), where we construct closed-form representations of all ( n-point N k MHV) scattering amplitudes through three loops. The prescriptive approach contrasts with the ordinary description of unitarity-based methods by avoiding any need for linear algebra to determine integrand coefficients. We describe this approach in general terms as it should have applications to many quantum field theories, including those without planarity, supersymmetry, or massless spectra defined in any number of dimensions.

  3. Prescription and

    Directory of Open Access Journals (Sweden)

    David Calderón-Guzmán

    2016-03-01

    Full Text Available Background: The knowledge about the pattern of prescription and consumption of solid oral drugs dispensed as unitary doses (UD in Mexico is sparing. Purpose: The aim of this study was to describe the pattern of prescription and consumption of solid oral drugs dispensed as unitary doses (UD in a third level private hospital of Mexico. A retrospective study of a 60-month period (from 2007 to 2011 was carried out to know the pattern of drugs dispensed as UD in a third level hospital. Results: Among the principal drugs consumed were analgesic, antihypertensive, antibiotic, anti-inflammatory, antiepileptic, and diuretics. The dispensation of drugs per year was as follows: 181 drugs with 85,167 UD in 2007; 199 with 90,519 UD in 2008; 193 with 101,479 UD in 2009; 195 with 100,798 UD in 2010; and 198 with 103,913 UD in 2011. Conclusion: The findings confirmed that prescription and consumption of unitary doses in the hospitalization service increased, and revealed the extensive use of analgesics as the principal prescribed drug in this kind of hospital.

  4. [Transparent evolution of the energy/matter interactions on earth: from gas whirlwind to technogenic civilization].

    Science.gov (United States)

    Pechurkin, N S; Shuvaev, A N

    2015-01-01

    The paper presents the idea of transparent evolution through the long-term reaction of the planet Earth on the external flow of radiant energy from the Sun. Due to limitations of matter on Earth, as well as on any other planet, the continuous pumping flow of radiant energy was shown to lead to cyclization and transport of substance on emerging gradients. The evolution of energy-matter interaction follows the path of capturing and transferring more energy by the fewer matter, i.e., the path of growth of the amount of energy used by each unit mass. For this indicator, the least effective mass transfer is a simple mass transfer as vortices of gases, in the gradients of temperature and pressure, which occurred on the primary surface of the planet. A long-term natural selection related to the accumulation of water on the planet has played a special role in developing the interaction of energy and matter. Phase transformations (ice, water, vapor) and mechanical transfers are the most common energy-matter processes. Based on water cycles, cyclic transports and transformations, chemical transformation of substances became possible developing over time into a biological transformation. This kind of the interaction of energy and matter is most efficient. In particular, during photosynthesis the energy of our star "is captured and utilized" in the most active part of the spectrum of its radiation. In the process of biological evolution of heterotrophs, a rise (by a factor of hundreds) in the coefficient that characterizes the intensity of energy exchange from protozoa to mammals is most illustratory. The development and the current dominance of humans as the most energy-using active species in capturing the energy and meaningful organization of its new flows especially on the basis of organic debris of former biospheres is admirable, but quite natural from the energy positions. In the course of technological evolution of humankind, the measure of the intensity of energy for

  5. Geodynamic evolution of the Earth over 600 Ma: implications for palaeo-climatic indicators

    Science.gov (United States)

    Hochard, C.; Vérard, C.

    2011-12-01

    During the last decades numerous local reconstructions were developed by the Geodynamic School of Lausanne. They participated to the elaboration of a 600Ma to present global plate tectonics model* based on field geology and controlled by geometric and kinematic constraints. Plate tectonics principles and lithospheric behaviour were applied to the model that drastically differs from the continental drift approach (i.e. based on palaeomagnetic data). Step after step lithospheric plates were reconstructed by adding or removing oceanic material (symbolized by synthetic isochrones) to major continents. The geodynamic evolution obtained is thus physically coherent and covers the whole surface of the Earth for the Phanerozoic. In the present contribution, we detail the basic tectonic features making up the model and the way they can be tested against the main palaeoclimatic indicators. Using synthetic isochrones, we developed a series of ocean lithosphere age maps. Based on plate rotation poles we computed velocity maps showing accretion and convergence rates. Converting ages into lithosphere thicknesses we quantified the volume of subducting material. Such tectonic parameters can be compared with the evolution of chemical proxies (e.g. CO2, δ18O, 87Sr/86Sr, Mg/Ca, SO4) offering a different way to decipher long-term climate changes. * This work was carried out as part of work done within the research program of the University of Lausanne on the Stampfli geodynamic model, model which is now owned by Neftex Petroleum Consultants Ltd. and is now attached to the "Neftex Earth Model ".

  6. Thoughts on the diversity of convergent evolution of bioluminescence on earth

    Science.gov (United States)

    Waldenmaier, Hans E.; Oliveira, Anderson G.; Stevani, Cassius V.

    2012-10-01

    The widespread independent evolution of analogous bioluminescent systems is one of the most impressive and diverse examples of convergent evolution on earth. There are roughly 30 extant bioluminescent systems that have evolved independently on Earth, with each system likely having unique enzymes responsible for catalysing the bioluminescent reaction. Bioluminescence is a chemical reaction involving a luciferin molecule and a luciferase or photoprotein that results in the emission of light. Some independent systems utilize the same luciferin, such as the use of tetrapyrrolic compounds by krill and dinoflagellates, and the wide use of coelenterazine by marine organisms, while the enzymes involved are unique. One common thread among all the different bioluminescent systems is the requirement of molecular oxygen. Bioluminescence is found in most forms of life, especially marine organisms. Bioluminescence in known to benefit the organism by: attraction, repulsion, communication, camouflage, and illumination. The marine ecosystem is significantly affected by bioluminescence, the only light found in the pelagic zone and below is from bioluminescent organisms. Transgenic bioluminescent organisms have revolutionized molecular research, medicine and the biotechnology industry. The use of bioluminescence in studying molecular pathways and disease allows for non-invasive and real-time analysis. Bioluminescence-based assays have been developed for several analytes by coupling luminescence to many enzyme-catalysed reactions.

  7. Long term evolution of distant retrograde orbits in the Earth-Moon system

    Science.gov (United States)

    Bezrouk, Collin; Parker, Jeffrey S.

    2017-09-01

    This work studies the evolution of several Distant Retrograde Orbits (DROs) of varying size in the Earth-Moon system over durations up to tens of millennia. This analysis is relevant for missions requiring a completely hands off, long duration quarantine orbit, such as a Mars Sample Return mission or the Asteroid Redirect Mission. Four DROs are selected from four stable size regions and are propagated for up to 30,000 years with an integrator that uses extended precision arithmetic techniques and a high fidelity dynamical model. The evolution of the orbit's size, shape, orientation, period, out-of-plane amplitude, and Jacobi constant are tracked. It has been found that small DROs, with minor axis amplitudes of approximately 45,000 km or less decay in size and period largely due to the Moon's solid tides. Larger DROs (62,000 km and up) are more influenced by the gravity of bodies external to the Earth-Moon system, and remain bound to the Moon for significantly less time.

  8. Evolution of Earth-like Extrasolar Planetary Atmospheres: Assessing the Atmospheres and Biospheres of Early Earth Analog Planets with a Coupled Atmosphere Biogeochemical Model

    Science.gov (United States)

    Gebauer, S.; Grenfell, J. L.; Stock, J. W.; Lehmann, R.; Godolt, M.; von Paris, P.; Rauer, H.

    2017-01-01

    Understanding the evolution of Earth and potentially habitable Earth-like worlds is essential to fathom our origin in the Universe. The search for Earth-like planets in the habitable zone and investigation of their atmospheres with climate and photochemical models is a central focus in exoplanetary science. Taking the evolution of Earth as a reference for Earth-like planets, a central scientific goal is to understand what the interactions were between atmosphere, geology, and biology on early Earth. The Great Oxidation Event in Earth's history was certainly caused by their interplay, but the origin and controlling processes of this occurrence are not well understood, the study of which will require interdisciplinary, coupled models. In this work, we present results from our newly developed Coupled Atmosphere Biogeochemistry model in which atmospheric O2 concentrations are fixed to values inferred by geological evidence. Applying a unique tool (Pathway Analysis Program), ours is the first quantitative analysis of catalytic cycles that governed O2 in early Earth's atmosphere near the Great Oxidation Event. Complicated oxidation pathways play a key role in destroying O2, whereas in the upper atmosphere, most O2 is formed abiotically via CO2 photolysis. The O2 bistability found by Goldblatt et al. (2006) is not observed in our calculations likely due to our detailed CH4 oxidation scheme. We calculate increased CH4 with increasing O2 during the Great Oxidation Event. For a given atmospheric surface flux, different atmospheric states are possible; however, the net primary productivity of the biosphere that produces O2 is unique. Mixing, CH4 fluxes, ocean solubility, and mantle/crust properties strongly affect net primary productivity and surface O2 fluxes. Regarding exoplanets, different "states" of O2 could exist for similar biomass output. Strong geological activity could lead to false negatives for life (since our analysis suggests that reducing gases remove O2 that

  9. Coupled thermo-orbital evolution of tidally-evolved Earth-like planets

    Science.gov (United States)

    Behounkova, Marie; Walterova, Michaela; Cadek, Ondrej; Tobie, Gabriel; Choblet, Gael

    2016-10-01

    Progress in detection techniques of exoplanets inspired increasing number of studies focused on their internal dynamics and evolution. The detection methods tend to favor the discovery of short-period exoplanets, that are predicted to get rapidly tidally locked. During the locking process planets despin and a significant amount of tidal heating may contribute to the thermal budget of the planet. Moreover, tidally locked exoplanets exhibit large surface temperature contrasts between sub-stellar and anti-stellar sides due to uneven insolation which influence the convection pattern and cooling of the planet. Here, we will present the evolution of tidally locked Earth-like exoplanets using numerical tool Antigone (Behounkova et al., 2010, 2011) coupling long-term internal evolution, tidal dissipation (taking into account Maxwell or Andrade rheology) and uneven insolation pattern. For constant orbital parameters, we will focus on numerical simulation of the heat transfer in exoEarths for various rheological properties of planet and various values of spin-orbit resonance, semi-major axis, eccentricity and luminosity of star. In the case of effective heat transfer, our results suggest that the melting is mainly observed within the upper part of the mantle for tidal heating lower than 100TW . For tidal heating higher than 100TW, the melt is produced also within the deep part of the mantle and degree-2 convection is enhanced due to tidal heating pattern. For large tidal heating (larger than 1000TW), global melting is observed and temperature field is homogenized due to global melting, the heat transfer is mainly due to melt extraction and advection is suppressed. We will further present first results of coupled orbital-internal evolution of planets without companion using numerical model of orbital evolution with realistic (Maxwell or Andrade) rheology (Walterova et al., in prep). We will concentrate on the capture into the spin-orbit resonance. Special attention will be

  10. A study by computer simulation of the generation and evolution of the Earth`s magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Glatzmaier, G.A.; Hollerbach, R.; Roberts, P.H.

    1995-12-31

    Until recently very little has been known about the maintenance of the Earth`s magnetic field. The general consensus was that some type of convective motion edits in the Earth`s liquid iron alloy core that is affected by rotational forces in a way that continually generates new magnetic field to replace that which diffuses away. Magnetic-field reversals and secular variation have long been measured but no theory existed to explain these phenomena. To gain an understanding of the basic physical mechanisms of the ``geodynamo,`` we produced the first self-consistent computer simulation of convection and magnetic field generation in a rotating three-dimensional spherical fluid shell as an anologue to the Earth`s convective dynamo. This is a final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL).

  11. Towards an Integrated Model of Earth's Thermo-Chemical Evolution and Plate Tectonics

    Science.gov (United States)

    Tackley, P. J.; Xie, S.

    2001-05-01

    It has long been a challenge for geodynamicists, who have typically modeled homogeneous mantles, to explain the geochemical evidence for the existence of several distinct chemical reservoirs, in terms of a dynamically and chemically self-consistent model. While the mixing behavior of generalized tracers has received much attention in the modeling community, a recent trend has been towards mantle convection models that track the evolution of specific chemical species, both major and minor, and can thus be related to geochemical observations. However, obtaining realistic chemical evolution in such models is dependent on their having a reasonable representation of plate tectonic behavior since the recycling of oceanic crust and complementary depleted residuum is a key process in Earth that other terrestrial planets may lack. In general, this has required inserting plate motions by hand in models. In recent years, however, we have learned how to perform numerical simulations of mantle convection in which plate tectonic behavior is introduced self-consistently through plastic yielding of the lithosphere. In this presentation, models of mantle convection that combine a treatment of geochemical evolution with self-consistently generated plate tectonics, will be presented. Preliminary results indicate that the system can self-consistently evolve regions which have a HIMU-like signature as well as regions with a high He3/He4 ratio.

  12. Proceedings of the Astrobiology Science Conference 2010. Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond

    Science.gov (United States)

    2010-01-01

    The Program of the 2010 Astrobiology Science Conference: Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond, included sessions on: 50 Years of Exobiology and Astrobiology: Greatest Hits; Extraterrestrial Molecular Evolution and Pre-Biological Chemistry: From the Interstellar Medium to the Solar System I; Human Exploration, Astronaut Health; Diversity in Astrobiology Research and Education; Titan: Past, Present, and Future; Energy Flow in Microbial Ecosystems; Extraterrestrial Molecular Evolution and Prebiological Chemistry: From the Interstellar Medium to the Solar System II; Astrobiology in Orbit; Astrobiology and Interdisciplinary Communication; Science from Rio Tinto: An Acidic Environment; Can We Rule Out Spontaneous Generation of RNA as the Key Step in the Origin of Life?; How Hellish Was the Hadean Earth?; Results from ASTEP and Other Astrobiology Field Campaigns I; Prebiotic Evolution: From Chemistry to Life I; Adaptation of Life in Hostile Space Environments; Extrasolar Terrestrial Planets I: Formation and Composition; Collaborative Tools and Technology for Astrobiology; Results from ASTEP and Other Astrobiology Field Campaigns II; Prebiotic Evolution: From Chemistry to Life II; Survival, Growth, and Evolution of Microrganisms in Model Extraterrestrial Environments; Extrasolar Terrestrial Planets II: Habitability and Life; Planetary Science Decadal Survey Update; Astrobiology Research Funding; Bioessential Elements Through Space and Time I; State of the Art in Life Detection; Terrestrial Evolution: Implications for the Past, Present, and Future of Life on Earth; Psychrophiles and Polar Environments; Life in Volcanic Environments: On Earth and Beyond; Geochronology and Astrobiology On and Off the Earth; Bioessential Elements Through Space and Time II; Origins and Evolution of Genetic Systems; Evolution of Advanced Life; Water-rich Asteroids and Moons: Composition and Astrobiological Potential; Impact Events and Evolution; A Warm, Wet

  13. Proceedings of the Astrobiology Science Conference 2010. Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond

    Science.gov (United States)

    2010-01-01

    The Program of the 2010 Astrobiology Science Conference: Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond, included sessions on: 50 Years of Exobiology and Astrobiology: Greatest Hits; Extraterrestrial Molecular Evolution and Pre-Biological Chemistry: From the Interstellar Medium to the Solar System I; Human Exploration, Astronaut Health; Diversity in Astrobiology Research and Education; Titan: Past, Present, and Future; Energy Flow in Microbial Ecosystems; Extraterrestrial Molecular Evolution and Prebiological Chemistry: From the Interstellar Medium to the Solar System II; Astrobiology in Orbit; Astrobiology and Interdisciplinary Communication; Science from Rio Tinto: An Acidic Environment; Can We Rule Out Spontaneous Generation of RNA as the Key Step in the Origin of Life?; How Hellish Was the Hadean Earth?; Results from ASTEP and Other Astrobiology Field Campaigns I; Prebiotic Evolution: From Chemistry to Life I; Adaptation of Life in Hostile Space Environments; Extrasolar Terrestrial Planets I: Formation and Composition; Collaborative Tools and Technology for Astrobiology; Results from ASTEP and Other Astrobiology Field Campaigns II; Prebiotic Evolution: From Chemistry to Life II; Survival, Growth, and Evolution of Microrganisms in Model Extraterrestrial Environments; Extrasolar Terrestrial Planets II: Habitability and Life; Planetary Science Decadal Survey Update; Astrobiology Research Funding; Bioessential Elements Through Space and Time I; State of the Art in Life Detection; Terrestrial Evolution: Implications for the Past, Present, and Future of Life on Earth; Psychrophiles and Polar Environments; Life in Volcanic Environments: On Earth and Beyond; Geochronology and Astrobiology On and Off the Earth; Bioessential Elements Through Space and Time II; Origins and Evolution of Genetic Systems; Evolution of Advanced Life; Water-rich Asteroids and Moons: Composition and Astrobiological Potential; Impact Events and Evolution; A Warm, Wet

  14. Earth

    CERN Document Server

    Carter, Jason

    2017-01-01

    This curriculum-based, easy-to-follow book teaches young readers about Earth as one of the eight planets in our solar system in astronomical terms. With accessible text, it provides the fundamental information any student needs to begin their studies in astronomy, such as how Earth spins and revolves around the Sun, why it's uniquely suitable for life, its physical features, atmosphere, biosphere, moon, its past, future, and more. To enhance the learning experience, many of the images come directly from NASA. This straightforward title offers the fundamental information any student needs to sp

  15. NASA's Earth Observing System Data and Information System - Many Mechanisms for On-Going Evolution

    Science.gov (United States)

    Ramapriyan, H. K.

    2012-12-01

    NASA's Earth Observing System Data and Information System has been serving a broad user community since August 1994. As a long-lived multi-mission system serving multiple scientific disciplines and a diverse user community, EOSDIS has been evolving continuously. It has had and continues to have many forms of community input to help with this evolution. Early in its history, it had inputs from the EOSDIS Advisory Panel, benefited from the reviews by various external committees and evolved into the present distributed architecture with discipline-based Distributed Active Archive Centers (DAACs), Science Investigator-led Processing Systems and a cross-DAAC search and data access capability. EOSDIS evolution has been helped by advances in computer technology, moving from an initially planned supercomputing environment to SGI workstations to Linux Clusters for computation and from near-line archives of robotic silos with tape cassettes to RAID-disk-based on-line archives for storage. The network capacities have increased steadily over the years making delivery of data on media almost obsolete. The advances in information systems technologies have been having an even greater impact on the evolution of EOSDIS. In the early days, the advent of the World Wide Web came as a game-changer in the operation of EOSDIS. The metadata model developed for the EOSDIS Core System for representing metadata from EOS standard data products has had an influence on the Federal Geographic Data Committee's metadata content standard and the ISO metadata standards. The influence works both ways. As ISO 19115 metadata standard has developed in recent years, EOSDIS is reviewing its metadata to ensure compliance with the standard. Improvements have been made in the cross-DAAC search and access of data using the centralized metadata clearing house (EOS Clearing House - ECHO) and the client Reverb. Given the diversity of the Earth science disciplines served by the DAACs, the DAACs have developed a

  16. Tidal Heating of Earth-like Exoplanets around M Stars: Thermal, Magnetic, and Orbital Evolutions

    Science.gov (United States)

    Barnes, R.

    2015-01-01

    Abstract The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low-mass M stars whose radiative habitable zone overlaps with the “tidal zone,” where tidal dissipation is expected to be a significant heat source in the interior. We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a viscoelastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within 0.07 AU circularize before 10 Gyr, independent of initial eccentricity. Once circular, these planets cool monotonically and maintain dynamos similar to that of Earth. Planets forced into eccentric orbits can experience a super-cooling of the core and rapid core solidification, inhibiting dynamo action for planets in the habitable zone. We find that tidal heating is insignificant in the habitable zone around 0.45 (or larger) solar-mass stars because tidal dissipation is a stronger function of orbital distance than stellar mass, and the habitable zone is farther from larger stars. Suppression of the planetary magnetic field exposes the atmosphere to stellar wind erosion and the surface to harmful radiation. In addition to weak magnetic fields, massive melt eruption rates and prolonged magma oceans may render eccentric planets in the habitable zone of low-mass stars inhospitable for life. Key Words

  17. The hills are alive: Earth surface dynamics in the University of Arizona Landscape Evolution Observatory

    Science.gov (United States)

    DeLong, S.; Troch, P. A.; Barron-Gafford, G. A.; Huxman, T. E.; Pelletier, J. D.; Dontsova, K.; Niu, G.; Chorover, J.; Zeng, X.

    2012-12-01

    To meet the challenge of predicting landscape-scale changes in Earth system behavior, the University of Arizona has designed and constructed a new large-scale and community-oriented scientific facility - the Landscape Evolution Observatory (LEO). The primary scientific objectives are to quantify interactions among hydrologic partitioning, geochemical weathering, ecology, microbiology, atmospheric processes, and geomorphic change associated with incipient hillslope development. LEO consists of three identical, sloping, 333 m2 convergent landscapes inside a 5,000 m2 environmentally controlled facility. These engineered landscapes contain 1 meter of basaltic tephra ground to homogenous loamy sand and contains a spatially dense sensor and sampler network capable of resolving meter-scale lateral heterogeneity and sub-meter scale vertical heterogeneity in moisture, energy and carbon states and fluxes. Each ~1000 metric ton landscape has load cells embedded into the structure to measure changes in total system mass with 0.05% full-scale repeatability (equivalent to less than 1 cm of precipitation), to facilitate better quantification of evapotraspiration. Each landscape has an engineered rain system that allows application of precipitation at rates between3 and 45 mm/hr. These landscapes are being studied in replicate as "bare soil" for an initial period of several years. After this initial phase, heat- and drought-tolerant vascular plant communities will be introduced. Introduction of vascular plants is expected to change how water, carbon, and energy cycle through the landscapes, with potentially dramatic effects on co-evolution of the physical and biological systems. LEO also provides a physical comparison to computer models that are designed to predict interactions among hydrological, geochemical, atmospheric, ecological and geomorphic processes in changing climates. These computer models will be improved by comparing their predictions to physical measurements made in

  18. Continental growth and mantle hydration as intertwined feedback cycles in the thermal evolution of Earth

    Science.gov (United States)

    Höning, Dennis; Spohn, Tilman

    2016-06-01

    A model of Earth's continental coverage and mantle water budget is discussed along with its thermal evolution. The model links a thermal evolution model based on parameterized mantle convection with a model of a generic subduction zone that includes the oceanic crust and a sedimentary layer as carriers of water. Part of the subducted water is used to produce continental crust while the remainder is subducted into the mantle. The total length of the subduction zones is calculated from the total surface area of continental crust assuming randomly distributed continents. The mantle viscosity is dependent of temperature and the water concentration. Sediments are generated by continental crust erosion, and water outgassing at mid-oceanic ridges closes the water cycle. We discuss the strongly coupled, non-linear model using a phase plane defined by the continental coverage and mantle water concentration. Fixed points are found in the phase plane at which the rates of change of both variables are zero. These fixed points evolve with time, but in many cases, three fixed points emerge of which two are stable and an intermediate point is unstable with respect to continental coverage. With initial conditions from a Monte-Carlo scheme we calculate evolution paths in the phase plane and find a large spread of final states that all have a mostly balanced water budget. The present day observed 40% continental surface coverage is found near the unstable fixed point. Our evolution model suggests that Earth's continental coverage formed early and has been stable for at least 1.5 Gyr. The effect of mantle water regassing (and mantle viscosity depending on water concentration) is found to lower the present day mantle temperature by about 120 K, but the present day mantle viscosity is affected little. The water cycle thus complements the well-known thermostat effect of viscosity and mantle temperature. Our results further suggest that the biosphere could impact the feedback cycles by

  19. Proceedings of the Astrobiology Science Conference 2010. Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond

    Science.gov (United States)

    2010-01-01

    The Program of the 2010 Astrobiology Science Conference: Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond, included sessions on: 50 Years of Exobiology and Astrobiology: Greatest Hits; Extraterrestrial Molecular Evolution and Pre-Biological Chemistry: From the Interstellar Medium to the Solar System I; Human Exploration, Astronaut Health; Diversity in Astrobiology Research and Education; Titan: Past, Present, and Future; Energy Flow in Microbial Ecosystems; Extraterrestrial Molecular Evolution and Prebiological Chemistry: From the Interstellar Medium to the Solar System II; Astrobiology in Orbit; Astrobiology and Interdisciplinary Communication; Science from Rio Tinto: An Acidic Environment; Can We Rule Out Spontaneous Generation of RNA as the Key Step in the Origin of Life?; How Hellish Was the Hadean Earth?; Results from ASTEP and Other Astrobiology Field Campaigns I; Prebiotic Evolution: From Chemistry to Life I; Adaptation of Life in Hostile Space Environments; Extrasolar Terrestrial Planets I: Formation and Composition; Collaborative Tools and Technology for Astrobiology; Results from ASTEP and Other Astrobiology Field Campaigns II; Prebiotic Evolution: From Chemistry to Life II; Survival, Growth, and Evolution of Microrganisms in Model Extraterrestrial Environments; Extrasolar Terrestrial Planets II: Habitability and Life; Planetary Science Decadal Survey Update; Astrobiology Research Funding; Bioessential Elements Through Space and Time I; State of the Art in Life Detection; Terrestrial Evolution: Implications for the Past, Present, and Future of Life on Earth; Psychrophiles and Polar Environments; Life in Volcanic Environments: On Earth and Beyond; Geochronology and Astrobiology On and Off the Earth; Bioessential Elements Through Space and Time II; Origins and Evolution of Genetic Systems; Evolution of Advanced Life; Water-rich Asteroids and Moons: Composition and Astrobiological Potential; Impact Events and Evolution; A Warm, Wet

  20. Proceedings of the Astrobiology Science Conference 2010. Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond

    Science.gov (United States)

    2010-01-01

    The Program of the 2010 Astrobiology Science Conference: Evolution and Life: Surviving Catastrophes and Extremes on Earth and Beyond, included sessions on: 50 Years of Exobiology and Astrobiology: Greatest Hits; Extraterrestrial Molecular Evolution and Pre-Biological Chemistry: From the Interstellar Medium to the Solar System I; Human Exploration, Astronaut Health; Diversity in Astrobiology Research and Education; Titan: Past, Present, and Future; Energy Flow in Microbial Ecosystems; Extraterrestrial Molecular Evolution and Prebiological Chemistry: From the Interstellar Medium to the Solar System II; Astrobiology in Orbit; Astrobiology and Interdisciplinary Communication; Science from Rio Tinto: An Acidic Environment; Can We Rule Out Spontaneous Generation of RNA as the Key Step in the Origin of Life?; How Hellish Was the Hadean Earth?; Results from ASTEP and Other Astrobiology Field Campaigns I; Prebiotic Evolution: From Chemistry to Life I; Adaptation of Life in Hostile Space Environments; Extrasolar Terrestrial Planets I: Formation and Composition; Collaborative Tools and Technology for Astrobiology; Results from ASTEP and Other Astrobiology Field Campaigns II; Prebiotic Evolution: From Chemistry to Life II; Survival, Growth, and Evolution of Microrganisms in Model Extraterrestrial Environments; Extrasolar Terrestrial Planets II: Habitability and Life; Planetary Science Decadal Survey Update; Astrobiology Research Funding; Bioessential Elements Through Space and Time I; State of the Art in Life Detection; Terrestrial Evolution: Implications for the Past, Present, and Future of Life on Earth; Psychrophiles and Polar Environments; Life in Volcanic Environments: On Earth and Beyond; Geochronology and Astrobiology On and Off the Earth; Bioessential Elements Through Space and Time II; Origins and Evolution of Genetic Systems; Evolution of Advanced Life; Water-rich Asteroids and Moons: Composition and Astrobiological Potential; Impact Events and Evolution; A Warm, Wet

  1. Temporal Evolution of the Plasma Sheath Surrounding Solar Cells in Low Earth Orbit

    Science.gov (United States)

    Willis, Emily M.; Pour, Maria Z. A.

    2017-01-01

    High voltage solar array interactions with the space environment can have a significant impact on array performance and spacecraft charging. Over the past 10 years, data from the International Space Station has allowed for detailed observations of these interactions over long periods of time. Some of the surprising observations have been floating potential transients, which were not expected and are not reproduced by existing models. In order to understand the underlying processes producing these transients, the temporal evolution of the plasma sheath surrounding the solar cells in low Earth orbit is being investigated. This study includes lumped element modeling and particle-in-cell simulation methods. This presentation will focus on recent results from the on-going investigations.

  2. A new time tree reveals Earth history's imprint on the evolution of modern birds.

    Science.gov (United States)

    Claramunt, Santiago; Cracraft, Joel

    2015-12-01

    Determining the timing of diversification of modern birds has been difficult. We combined DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate a new time tree for Neornithes and investigated their biogeographic and diversification dynamics. We found that the most recent common ancestor of modern birds inhabited South America around 95 million years ago, but it was not until the Cretaceous-Paleogene transition (66 million years ago) that Neornithes began to diversify rapidly around the world. Birds used two main dispersion routes: reaching the Old World through North America, and reaching Australia and Zealandia through Antarctica. Net diversification rates increased during periods of global cooling, suggesting that fragmentation of tropical biomes stimulated speciation. Thus, we found pervasive evidence that avian evolution has been influenced by plate tectonics and environmental change, two basic features of Earth's dynamics.

  3. Os isotopes in SNC meteorites and their implications to the early evolution of Mars and Earth

    Science.gov (United States)

    Jagoutz, E.; Luck, J. M.; Othman, D. Ben; Wanke, H.

    1993-01-01

    A new development on the measurement of the Os isotopic composition by mass spectrometry using negative ions opened a new field of applications. The Re-Os systematic provides time information on the differentiation of the nobel metals. The nobel metals are strongly partitioned into metal and sulphide phases, but also the generation of silicate melts might fractionate the Re-Os system. Compared to the other isotopic systems which are mainly dating the fractionation of the alkalis and alkali-earth elements, the Re-Os system is expected to disclose entirely new information about the geochemistry. Especially the differentiation and early evolution of the planets such as the formation of the core will be elucidated with this method.

  4. Astrophysics and Weak Form of Panspermia Hypothesis and Exogenous Factors in the Evolution of the Earth

    Science.gov (United States)

    Adushkin, V. V.; Vityazev, A. V.; Glazachev, D. O.; Pechernikova, G. V.

    2014-10-01

    The problems of the origin of Earth and life are fundamental in the modern science. We, relying on the data of resent years, contemplate a new course of research in this old problem. On the base of astrophysical data, obtained during the last 30-50 years, and the resent results of the study of small bodies in the Solar System (comets in particular) it is possible to combine the old idea about panspermia in a comprehensive sense and the search of the basis of life on the early Earth grounded on theoretical and laboratory data on the Earth evolution. Most likely, the Sun and a gas-and-dust disk surrounding it were created in a Giant molecular cloud near young giants - blue O-B-stars which ultraviolet radiation provided a weak chirality (to 15% of EEs) in organics of interstellar dust. Further a part of interstellar dust beyond orbits larger than 3-4 a.u. remained cold and then entered into the first planetesimals. The organics, after melting of interiors of the first planetesimals due to the heating by shortliving 26Al and 60Fe, sank, in the form of kerogens, into the core where formation of the first complex organic compounds began. This occurred in the first 3-4 Myr after the CAI. Apparently, it is necessary to look for anaerobic life in comets. In geosciences obtained various data banks, such as data on the endogenous activity of the Earth, mass extinctions of life and changes in biodiversity, impacts of cosmic bodies, inversions of the magnetic field, climate change, etc. The problem of cyclicity and correlation of all these processes is studied for 50 years. Results of spectral, wavelet and correlation analysis of the data series, representing some of these processes are given. We conclude, that most of them are cyclic, some of the periods are present in all the processes. The mechanisms of the influence of the galaxy on the processes occurring on the Earth are discussed.

  5. Evolution of Earth-like Extrasolar Planetary Atmospheres: Assessing the Atmospheres and Biospheres of Early Earth Analog Planets with a Coupled Atmosphere Biogeochemical Model.

    Science.gov (United States)

    Gebauer, S; Grenfell, J L; Stock, J W; Lehmann, R; Godolt, M; von Paris, P; Rauer, H

    2017-01-01

    Understanding the evolution of Earth and potentially habitable Earth-like worlds is essential to fathom our origin in the Universe. The search for Earth-like planets in the habitable zone and investigation of their atmospheres with climate and photochemical models is a central focus in exoplanetary science. Taking the evolution of Earth as a reference for Earth-like planets, a central scientific goal is to understand what the interactions were between atmosphere, geology, and biology on early Earth. The Great Oxidation Event in Earth's history was certainly caused by their interplay, but the origin and controlling processes of this occurrence are not well understood, the study of which will require interdisciplinary, coupled models. In this work, we present results from our newly developed Coupled Atmosphere Biogeochemistry model in which atmospheric O2 concentrations are fixed to values inferred by geological evidence. Applying a unique tool (Pathway Analysis Program), ours is the first quantitative analysis of catalytic cycles that governed O2 in early Earth's atmosphere near the Great Oxidation Event. Complicated oxidation pathways play a key role in destroying O2, whereas in the upper atmosphere, most O2 is formed abiotically via CO2 photolysis. The O2 bistability found by Goldblatt et al. ( 2006 ) is not observed in our calculations likely due to our detailed CH4 oxidation scheme. We calculate increased CH4 with increasing O2 during the Great Oxidation Event. For a given atmospheric surface flux, different atmospheric states are possible; however, the net primary productivity of the biosphere that produces O2 is unique. Mixing, CH4 fluxes, ocean solubility, and mantle/crust properties strongly affect net primary productivity and surface O2 fluxes. Regarding exoplanets, different "states" of O2 could exist for similar biomass output. Strong geological activity could lead to false negatives for life (since our analysis suggests that reducing gases remove O2 that

  6. Geoethics and philosophy of Earth sciences: the role of geophysical factors in human evolution

    Directory of Open Access Journals (Sweden)

    Telmo Pievani

    2012-07-01

    Full Text Available This article explores the role of philosophy of the Earth sciences in the foundation of the principles of ‘geoethics’. In particular, the focus is on two different examples of philosophical analysis in the field of geosciences: the first is the trial against the Italian National Commission for Forecasting and Predicting Great Risks, which was charged with negligence in communication and prediction on the occasion of the earthquake that almost destroyed the city of L’Aquila on the night of April 6, 2009; the second is related to the scientific and theoretical consequences of the updated geographical scenario of the human global populating of the Earth, based on archeological, paleontological and genetic data. Our concept of ‘scientific prediction’ in the case of geophysical phenomena and the new ways to see human evolution that depend on geophysical factors have ethical and philosophical implications that are crucial for the foundations of geoethics. The tentative conclusion is that we need an evolutionary sense of belonging to our Planet, and a concept of ‘natural’ phenomena and ‘natural’ disasters that should not be an alibi for the underestimation of our political and ethical responsibilities.

  7. On the importance of lowermost mantle melt in the long term evolution of the Earth

    Science.gov (United States)

    Labrosse, S.; Hernlund, J. W.; Coltice, N.

    2011-12-01

    The thermal evolution of the Earth is usually modeled using its global energy balance and a scaling law for the heat transfer by mantle convection where the heat flow q depends on the mantle potential temperature T and its viscosity η as q=AT1+βη-β, with typical fluid dynamics models giving β≈1/3. The present small ratio of heat production to heat loss (Urey ratio) implies a large secular cooling rate and, because of the feedback from temperature dependent viscosity, backward calculations from the present time lead to a completely molten Earth about 1 Gyr ago. Starting with Christensen (1985), values of β smaller than 1/3 have been proposed to solve this problem by reducing the strength of the feedback loop between core temperature and surface heat flow. However, a self-consistent theory of mantle convection is still lacking to justify unconventional β values. We propose an entirely different approach recognizing that the lowermost mantle, which presently shows evidence of partial melting (ULVZs), was likely largely molten in its hotter past. Coupling a parameterized model of mantle convection using standard scalings for the solid upper part to a crystallizing basal magma ocean (BMO) enriched in radioactive elements and the core cuts the feedback loop very efficiently by introducing two independent potential temperatures. Backward integration of the model makes the core and the BMO hotter in the past while keeping the solid mantle temperature reasonable. A thermal catastrophe may in fact have happened, but only deep in the Earth!

  8. On the effects of the evolution of microbial mats and land plants on the Earth as a planet. Photometric and spectroscopic light curves of paleo-Earths

    CERN Document Server

    Sanromá, E; García-Muñoz, A

    2013-01-01

    Understanding the spectral and photometric variability of the Earth and the rest of the Solar System planets has become of the utmost importance for the future characterization of rocky exoplanets. As this is not only interesting at present times but also along the planetary evolution, we studied the effect that the evolution of microbial mats and plants over land has had on the way our planet looks from afar. As life evolved, continental surfaces changed gradually and non- uniformly from deserts through microbial mats to land plants, modifying the reflective properties of the ground and most probably the distribution of moisture and cloudiness. Here, we used a radiative transfer model of the Earth, together with geological paleo-records of the continental distribution and a reconstructed cloud distribution, to simulate the visible and near-IR radiation reflected by our planet as a function of the Earth's rotation. We found that the evolution from deserts to microbial mats and to land plants produce detectabl...

  9. Water and the Earth System in the Anthropocene: Evolution of Socio-Hydrology

    Science.gov (United States)

    Sivapalan, M.; Bloeschl, G.

    2014-12-01

    Over the past century, hydrological science has evolved through distinct eras as judged by ideas, information sources, technological advances and societal influences: Empirical Era which was data based with little theory, Systems Era that focused on input-output relationships, Process Era with a focus on processes, and the Geosciences Era where hydrology was considered an Earth System science. We argue that as the human footprint on earth becomes increasingly dominant, we are moving into a Co-evolution Era. Co-evolution implies that the components of the Earth system are intimately intertwined at many time scales - fast scales of immediate feedbacks that translate into slow scale interdependencies and trends. These involve feedbacks between the atmosphere, biota, soils and landforms, mediated by water flow and transport processes. The human factor is becoming a key component of this coupled system. While there is a long tradition of considering effects of water on humans, and vice versa, the new thrust on socio-hydrology has a number of defining characteristics that sets it apart from traditional approaches: - Capturing feedbacks of human-natural water system in a dynamic way (slow and fast processes) to go beyond prescribing human factors as mere boundary conditions. These feedbacks will be essential to understand how the system may evolve in the future into new, perhaps previously unobserved, states. - Quantifying system dynamics in a generalizable way. So far, water resources assessment has been context dependent, tied to local conditions. While for immediate decision making this is undoubtedly essential, for more scientific inquiry, a more uniform knowledge base is indispensable. - Not necessarily predictive. The coupled human-nature system is inherently non-linear, which may prohibit predictability in the traditional sense. The socio-hydrologic approach may still be predictive in a statistical sense and, perhaps even more importantly, it may yet reveal

  10. Opioid Basics: Prescription Opioids

    Science.gov (United States)

    ... Injury Violence Prevention WISQARS (Injury & Death Data) Prescription Opioids Recommend on Facebook Tweet Share Compartir Prescription opioids ... overdose before they start. Risk Factors for Prescription Opioid Abuse and Overdose Research shows that some risk ...

  11. Prescription Drug Abuse

    Science.gov (United States)

    ... over-the-counter medications. National Institute on Drug Abuse. http://www.drugabuse.gov/publications/drugfacts/prescription-over-counter- ... 2015. Prescription drug abuse. National Institute on Drug Abuse. http://www.drugabuse.gov/publications/research-reports/prescription-drugs/ ...

  12. Tracing Earth's O2 Evolution Using Zn/Fe Systematics in Carbonates

    Science.gov (United States)

    Liu, X. M.; Hazen, R. M.; Kah, L. C.; Sverjensky, D. A.; Cui, H.; Kaufmann, A. J.

    2014-12-01

    Redox-sensitive major and trace elements in iron formations and black shales have been developed as proxies to reconstruct paleoenvironmental history in deep time [1, 2]. Many Proterozoic successions, however, contain abundant limestone and dolomite, and so carbonate-based redox proxies could help greatly to expand the paleoredox record in time and space. Most paleoenvironmental research on sedimentary rocks focuses on individual stratigraphic successions; here, however, we adopt a complementary strategy, analyzing a large suite of Mesozoic, Paleozoic, and Precambrian samples that enables us to make global statistical statements about elemental abundances through time. Here we explore the use of Zn/Fe ratios as proxies to trace the evolution of redox profiles in marine basins, based on analysis of major and trace element concentrations in micro-drilled carbonate rocks that are well characterized in terms of stratigraphy, environmental setting, and petrology. Consistent with previous studies, we observed a two step increase of mean Zn/Fe ratios in carbonates through Earth history: at the Paleoproterozoic Great Oxidation Event and during the later Neoproterozoic Oxidation Event. Diagenetic alteration is always an issue for carbonate rocks, and so we carefully screened these carbonates for possible late diagenetic effects and hydrothermal alteration. Individual samples may still bear a trace element signature of early diagenesis, but our statistical approach indicates that despite diagenetic issues, meaningful trends can be discerned in the data. It is unlikely that changes in depositional environment, secular evolution of the mantle, and/or directional change in continental inputs greatly influenced the observed trace element behavior. Therefore, Zn/Fe ratios in shallow marine carbonates have the potential to provide a useful tracer for the redox evolution of the oceans and the rise of atmospheric O2. References:[1] Sahoo et al. (2012) Ocean oxygenation in the wake

  13. Early evolution and dynamics of Earth from a molten initial stage

    Science.gov (United States)

    Louro Lourenço, Diogo; Tackley, Paul J.

    2016-04-01

    It is now well established that most of the terrestrial planets underwent a magma ocean stage during their accretion. On Earth, it is probable that at the end of accretion, giant impacts like the hypothesised Moon-forming impact, together with other sources of heat, melted a substantial part of the mantle. The thermal and chemical evolution of the resulting magma ocean most certainly had dramatic consequences on the history of the planet. Considerable research has been done on magma oceans using simple 1-D models (e.g.: Abe, PEPI 1997; Solomatov, Treat. Geophys. 2007; Elkins-Tanton EPSL 2008). However, some aspects of the dynamics may not be adequately addressed in 1-D and require the use of 2-D or 3-D models. Moreover, new developments in mineral physics that indicate that melt can be denser than solid at high pressures (e.g.: de Koker et al., EPSL 2013) can have very important impacts on the classical views of the solidification of magma oceans (Labrosse et al., Nature 2007). The goal of our study is to understand and characterize the influence of melting on the long-term thermo-chemical evolution of rocky planet interiors, starting from an initial molten state (magma ocean). Our approach is to model viscous creep of the solid mantle, while parameterizing processes that involve melt as previously done in 1-D models, including melt-solid separation at all melt fractions, the use of an effective diffusivity to parameterize turbulent mixing, coupling to a parameterized core heat balance and a radiative surface boundary condition. These enhancements have been made to the numerical code StagYY (Tackley, PEPI 2008). We present results for the evolution of an Earth-like planet from a molten initial state to present day, while testing the effect of uncertainties in parameters such as melt-solid density differences, surface heat loss and efficiency of turbulent mixing. Our results show rapid cooling and crystallization until the rheological transition then much slower

  14. A model for the evolution of the Earth's mantle structure since the Early Paleozoic

    Science.gov (United States)

    Zhang, Nan; Zhong, Shijie; Leng, Wei; Li, Zheng-Xiang

    2010-06-01

    Seismic tomography studies indicate that the Earth's mantle structure is characterized by African and Pacific seismically slow velocity anomalies (i.e., superplumes) and circum-Pacific seismically fast anomalies (i.e., a globally spherical harmonic degree 2 structure). However, the cause for and time evolution of the African and Pacific superplumes and the degree 2 mantle structure remain poorly understood with two competing proposals. First, the African and Pacific superplumes have remained largely unchanged for at least the last 300 Myr and possibly much longer. Second, the African superplume is formed sometime after the formation of Pangea (i.e., at 330 Ma) and the mantle in the African hemisphere is predominated by cold downwelling structures before and during the assembly of Pangea, while the Pacific superplume has been stable for the Pangea supercontinent cycle (i.e., globally a degree 1 structure before the Pangea formation). Here, we construct a proxy model of plate motions for the African hemisphere for the last 450 Myr since the Early Paleozoic using the paleogeographic reconstruction of continents constrained by paleomagnetic and geological observations. Coupled with assumed oceanic plate motions for the Pacific hemisphere, this proxy model for the plate motion history is used as time-dependent surface boundary condition in three-dimensional spherical models of thermochemical mantle convection to study the evolution of mantle structure, particularly the African mantle structure, since the Early Paleozoic. Our model calculations reproduce well the present-day mantle structure including the African and Pacific superplumes and generally support the second proposal with a dynamic cause for the superplume structure. Our results suggest that while the mantle in the African hemisphere before the assembly of Pangea is predominated by the cold downwelling structure resulting from plate convergence between Gondwana and Laurussia, it is unlikely that the bulk of

  15. Heat flow evolution of the Earth from paleomantle temperatures: Evidence for increasing heat loss since ∼2.5 Ga

    Science.gov (United States)

    Ruiz, Javier

    2017-08-01

    Earth currently loses two to five times as much heat through its surface as it is internally produced by radioactivity. This proportion cannot be extrapolated into the past, because it would imply high interior temperatures and catastrophic melting of the planet in ancient times. The heat loss evolution of the Earth cannot therefore be described by a constant heat flow decreasing. This is consistent with previous work finding that the mantle heated up until ∼2.5-3.0 Ga and then progressively cooled down. The present work derives a first-order heat loss evolution of the Earth by comparing the evolution of the total heat content of the silicate Earth (as described by mantle potential temperatures deduced from the melting conditions of ancient non-arc basalts) with the total radioactive heat production. The results show that the heat flow was declining, and the mantle heating-up, until ∼2.5 Ga, but that after this time the heat flow has been slowly (but constantly) increasing, and the mantle cooling-down, until the present-day. The change in heat loss trend is roughly coeval with other major geological, geochemical and environmental changes, and could indicate the starting of the modern-style of plate tectonics. This work provides therefore the first quantitative evidence of change in terrestrial heat loss regime, and suggests that substantial variations in the internal heat budget occurred during Earth's history.

  16. Past Plate Motions and The Evolution of Earth's Lower Mantle: Relating LLSVPs and Plume Distribution

    Science.gov (United States)

    Bull, A. L.; Torsvik, T. H.; Shephard, G. E.

    2015-12-01

    Seismic tomography elucidates broad, low shear-wave velocity structures in the lower mantle beneath Africa and the central Pacific with uncertain physical and compositional origins. The anomalously slow areas, which cover nearly 50% of the core-mantle boundary, are often referred to as Large Low Shear Velocity Provinces (LLSVPs) due to the reduced velocity of seismic waves passing through them. Several hypotheses have arisen to explain the LLSVPs in the context of large-scale mantle convection. One end-member scenario infers a spatial correlation between LLSVP margins at depth and the reconstructed surface eruption sites of hotspots, kimberlites, and Large Igneous Provinces. Such a correlation has been explained by the preferential triggering of plumes at LLSVP margins by impingement of the subducting lithosphere upon the lower thermal boundary layer at the interface between ambient mantle and the higher density structures. This scenario propounds that Earth's plate motion history plays a controlling role in plume development, and that the location, geometry and morphology of plumes may be influenced by the movement of subducting slabs. Here, we investigate what is necessary to create such a pattern of plume distribution in relation to LLSVPs. We consider what effect past plate motions may have had on the evolution of Earth's lower mantle, and discuss the development of mantle plumes in terms of subduction dynamics. We integrate plate tectonic histories and numerical models of mantle convection to investigate the role that subduction history plays in the development and evolution of plumes in the presence of LLSVPs. To test whether an interaction exists between the surface location of subduction and plume eruption sites, and if so, to what degree over time, we apply varying shifts to the absolute reference frame of the plate reconstruction. With this method, we are able to change the location of subduction at the surface and thus the global flow field. This in turn

  17. Oxygenation of Earth's atmosphere and its impact on the evolution of nitrogen-based metabolisms

    Science.gov (United States)

    Papineau, D.; Mojzsis, S. J.

    2002-12-01

    The evolution of metabolic pathways is closely linked to the evolution of the redox state of the terrestrial atmosphere. Nitrogen has been an essential biological element since the emergence of life when reduced nitrogen compounds (e.g. ammonia) were utilized in the prebiotic synthesis of proteins and nucleic acids. The nitrogen isotopic composition of sediments has been used to trace the origin of sedimentary organic matter in the rock record. Nitrogen is therefore suitable as a biosignature to trace the emergence of life on Earth or other planetary bodies as well as to follow the subsequent evolution of the biosphere in response to global redox changes. Evidence is strong that biological nitrogen fixation evolved very early in the history of life. The Last Common Ancestor (LCA) on Earth was most likely capable of nitrogen fixation as seen from the phylogenetic distribution of nitrogen-fixing organisms in both the domains of Bacteria and Archaea. Phylogenetic trees plotted with nitrogen-fixing gene (Nif) sequences from lineages of Bacteria and Archaea suggest that the Nif genes originated in a common ancestor of the two domains. Other phylogenetic analyses have also demonstrated that the paralogous duplication of the nifDK and nifEN operons, central to nitrogen fixation, predated the divergence of Archaea from Bacteria and therefore occurred prior to the emergence of the LCA. Although the same may be true for denitrification, this metabolic pathway probably did not become dominant until atmospheric pO2 increased between ~2.4 to 1.9 Ga during the Great Oxygenation Event (GOE). Recent work has shown a general depletion in 15N content of Archean (pre-2.5 Ga) relative to Phanerozoic (<540 Ma) kerogens. Studies have shown that the distribution of the δ15N values in kerogens shift from negative values in the Early Archean (from -6 to +6‰ with an average near 0‰ ) to approximately contemporary positive values (from +2 to +10‰ with an average at +6‰ ) by the

  18. Evolution of Electron Transport Chains During the Anaerobic to Aerobic Transition on Early Earth

    Science.gov (United States)

    Sepúlveda, R.; Ortiz, R.; Holmes, D. S.

    2015-12-01

    Sepulveda, R., Ortiz R. and Holmes DS. Center for Bioinformatics and Genome Biology, Fundacion Ciencia y Vida, and Facultad de Ciencias Biologicas, Universidad Andres Bello, Santiago, Chile.According to several models, life emerged on earth in an anoxic environment where oxygen was not available as a terminal electron acceptor for energy generating reactions. After the Great Oxidation Event (GOE) about 2.4 billion years ago, or perhaps even before the GOE, oxygen became the most widespread and efficient terminal electron acceptor and was accompanied by the evolution of a number of redox proteins that could deliver electrons to reduce oxygen to water. Where did these proteins come from? One hypothesis is that they evolved by the neofunctionalization of previously existing redox proteins that had been used in anaerobic conditions as terminal electron donors to reduce compounds such as perchlorate, nitric oxide or iron. We have used a number of bioinformatic tools to explore a large number of genomes looking for discernable signals of such redeployment of function. A Perl pipeline was designed to detect sequence similarity, conserved gene context, remote homology detection, identification of domains and functional evolution of electron carrier proteins from extreme acidophiles, including the small blue copper protein rusticyanin (involved in FeII oxidation), cytochrome oxidase subunit II and quinol-dependent nitric oxide reductase (qNOR). The protein folds and copper binding sites of rusticyanin are conserved in cytochrome oxidase aa3 subunit II, a protein complex that is responsible for the final passage of electrons to reduce oxygen. Therefore, we hypothesize that rusticyanin, cytochrome oxidase II and qNOR are evolutionarily related. Acknowledgments: Fondecyt 1130683.

  19. Geodynamic evolution of the Earth over the Phanerozoic: Plate tectonic activity and palaeoclimatic indicators

    Directory of Open Access Journals (Sweden)

    Christian Vérard

    2015-04-01

    In this paper, we compare values derived from the tectonic model (ages of oceanic floor, production and subduction rates, tectonic activity with a combination of chemical proxies (namely CO2, 87Sr/86Sr, glaciation evidence, and sea-level variations known to be strongly influenced by tectonics. One of the outstanding results is the observation of an overall decreasing trend in the evolution of the global tectonic activity, mean oceanic ages and plate velocities over the whole Phanerozoic. We speculate that the decreasing trend reflects the global cooling of the Earth system. Additionally, the parallel between the tectonic activity and CO2 together with the extension of glaciations confirms the generally accepted idea of a primary control of CO2 on climate and highlights the link between plate tectonics and CO2 in a time scale greater than 107 yr. Last, the wide variations observed in the reconstructed sea-floor production rates are in contradiction with the steady-state model hypothesized by some.

  20. Thermal evolution and interior models of the transiting super-Earth GJ 1214b

    CERN Document Server

    Nettelmann, N; Kramm, U; Redmer, R

    2010-01-01

    The planet GJ 1214b is the second known super-Earth with a measured mass and radius. Orbiting a quiet M-star, it receives considerably less mass-loss driving X-ray and UV radiation than CoRoT-7b, so that the interior may be quite dissimilar in composition, including the possibility of a large fraction of water. We model the interior of GJ 1214b assuming a two-layer (envelope+rock core) structure where the envelope material is either H/He, pure water, or a mixture of H/He and H2O. Within this framework we perform models of the thermal evolution and contraction of the planet. We discuss possible compositions that are consistent with Mp=6.55 ME, Rp=2.678 RE, an age tau=3-10 Gyr, and the irradiation level of the atmosphere. These conditions require that if water exists in the interior, it must remain in a fluid state, with important consequences for magnetic field generation. These conditions also require the atmosphere to have a deep isothermal region extending down to 80-800 bar, depending on composition. Our r...

  1. Geodynamic evolution of the Earth over the Phanerozoic:Plate tectonic activity and palaeoclimatic indicators

    Institute of Scientific and Technical Information of China (English)

    Christian Vérard; Cyril Hochard; Peter O. Baumgartner; Gérard M. Stamplfi

    2015-01-01

    During the last decades, numerous local reconstructions based on ifeld geol-ogy were developed at the University of Lausanne (UNIL). Team members of the UNIL partici-pated in the elaboration of a 600 Ma to present global plate tectonic model deeply rooted in geological data, controlled by geometric and kinematic constraints and coherent with forces acting at plate boundaries. In this paper, we compare values derived from the tectonic model (ages of oceanic lfoor, production and subduction rates, tectonic activity) with a combination of chemical proxies (namely CO2, 87Sr/86Sr, glaciation evidence, and sea-level variations) known to be strongly in-lfuenced by tectonics. One of the outstanding results is the observation of an overall decreas-ing trend in the evolution of the global tectonic activity, mean oceanic ages and plate velocities over the whole Phanerozoic. We speculate that the decreasing trend relfects the global cooling of the Earth system. Additionally, the parallel between the tectonic activity and CO2 together with the extension of glaciations conifrms the generally accepted idea of a primary control of CO2 on climate and highlights the link between plate tectonics and CO2 in a time scale greater than 107 yr. Last, the wide variations observed in the reconstructed sea-lfoor production rates are in contradiction with the steady-state model hypothesized by some.

  2. Crystallization of silicon dioxide and compositional evolution of the Earth's core.

    Science.gov (United States)

    Hirose, Kei; Morard, Guillaume; Sinmyo, Ryosuke; Umemoto, Koichio; Hernlund, John; Helffrich, George; Labrosse, Stéphane

    2017-03-02

    The Earth's core is about ten per cent less dense than pure iron (Fe), suggesting that it contains light elements as well as iron. Modelling of core formation at high pressure (around 40-60 gigapascals) and high temperature (about 3,500 kelvin) in a deep magma ocean predicts that both silicon (Si) and oxygen (O) are among the impurities in the liquid outer core. However, only the binary systems Fe-Si and Fe-O have been studied in detail at high pressures, and little is known about the compositional evolution of the Fe-Si-O ternary alloy under core conditions. Here we performed melting experiments on liquid Fe-Si-O alloy at core pressures in a laser-heated diamond-anvil cell. Our results demonstrate that the liquidus field of silicon dioxide (SiO2) is unexpectedly wide at the iron-rich portion of the Fe-Si-O ternary, such that an initial Fe-Si-O core crystallizes SiO2 as it cools. If crystallization proceeds on top of the core, the buoyancy released should have been more than sufficient to power core convection and a dynamo, in spite of high thermal conductivity, from as early on as the Hadean eon. SiO2 saturation also sets limits on silicon and oxygen concentrations in the present-day outer core.

  3. Open system models of isotopic evolution in Earth's silicate reservoirs: Implications for crustal growth and mantle heterogeneity

    Science.gov (United States)

    Kumari, Seema; Paul, Debajyoti; Stracke, Andreas

    2016-12-01

    An open system evolutionary model of the Earth, comprising continental crust (CC), upper and lower mantle (UM, LM), and an additional isolated reservoir (IR) has been developed to study the isotopic evolution of the silicate Earth. The model is solved numerically at 1 Myr time steps over 4.55 Gyr of Earth history to reproduce both the present-day concentrations and isotope ratios of key radioactive decay systems (Rb-Sr, Sm-Nd, and U-Th-Pb) in these terrestrial reservoirs. Various crustal growth scenarios - continuous versus episodic and early versus late crustal growth - and their effect on the evolution of Sr-Nd-Pb isotope systematics in the silicate reservoirs have been evaluated. Modeling results where the present-day UM is ∼60% of the total mantle mass and a lower mantle that is non-primitive reproduce the estimated geochemical composition and isotope ratios in Earth's silicate reservoirs. The isotopic evolution of the silicate Earth is strongly affected by the mode of crustal growth; only an exponential crustal growth pattern with crustal growth since the early Archean satisfactorily explains the chemical and isotopic evolution of the crust-mantle system and accounts for the so-called Pb paradoxes. Assuming that the OIB source is located in the deeper mantle, our model could, however, not reproduce its target ɛNd of +4.6 for the UM, which has been estimated from the average isotope ratios of 32 individual ocean island localities. Hence, either mantle plumes sample the LM in a non-representative way, or the simplified model set-up does not capture the full complexity of Earth's lower mantle (Nd isotope) evolution. Compared to the results obtained for a 4.55 Ga Earth, a model assuming a protracted U-Pb evolution of silicate Earth by ca. 100 Myr reproduces a slightly better fit for the Pb isotope ratios in Earth's silicate reservoirs. One notable feature of successful models is the early depletion of incompatible elements (as well as rapid decrease in Th/U) in

  4. Evolution of nutritional therapy prescription in critically ill patients Evolución de la prescripción de la terapia nutricional en pacientes críticamente enfermos

    OpenAIRE

    D. Borges Dock-Nascimento; V. Maeve Tavares; J. E. Aguilar-Nascimento

    2005-01-01

    Aim: The aim of this study was to investigate factors that may affect the evolution of the caloric prescription in critically ill patients. Local: Intensive care unit patients. Patients: 60 patients (33 M and 27 F); median age = 49 (15-93) y were followed prospectively. They were divided in three groups according to the diagnostic: a) trauma (n = 20); b) surgical (n = 22), and 3) medical treatment (n = 18). Forty-and-one (68.3%) patients received enteral nutrition (EN), 17 (28.3%) parenteral ...

  5. Precambrian supercontinents, glaciations, atmospheric oxygenation, metazoan evolution and an impact that may have changed the second half of Earth history

    OpenAIRE

    Grant M. Young

    2013-01-01

    In more than 4 Ga of geological evolution, the Earth has twice gone through extreme climatic perturbations, when extensive glaciations occurred, together with alternating warm periods which were accompanied by atmospheric oxygenation. The younger of these two episodes of climatic oscillation preceded the Cambrian “explosion” of metazoan life forms, but similar extreme climatic conditions existed between about 2.4 and 2.2 Ga. Over long time periods, changing solar luminosity and mantle tempera...

  6. Biogeochemical Signatures in Precambrian Black Shales: Window Into the Co-Evolution of Ocean Chemistry and Life on Earth

    OpenAIRE

    Scott, Clinton

    2009-01-01

    The degradation of sedimentary organic matter drives a suite of biologically- mediated redox reactions that in turn reflect the chemical composition of pore waters and bottom waters on local to global scales. By analyzing the chemical and isotopic composition of modern sediments and ancient black shales, biogeochemists can track the evolution of ocean/atmosphere redox conditions, the chemical composition of the oceans, and the evolutionary course of life throughout Earth history. Chapter 1 in...

  7. Tidal dissipation in the lunar magma ocean and its effect on the early evolution of the Earth-Moon system

    Science.gov (United States)

    Chen, Erinna M. A.; Nimmo, Francis

    2016-09-01

    The present-day inclination of the Moon reflects the entire history of its thermal and orbital evolution. The Moon likely possessed a global magma ocean following the Moon-forming impact. In this work, we develop a coupled thermal-orbital evolution model that takes into account obliquity tidal heating in the lunar magma ocean. Dissipation in the magma ocean is so effective that it results in rapid inclination damping at semi-major axes beyond about 20 Earth radii (RE), because of the increase in lunar obliquity as the so-called Cassini state transition at ≈30 RE is approached. There is thus a "speed limit" on how fast the Moon can evolve outwards while maintaining its inclination: if it reaches 20 RE before the magma ocean solidifies, any early lunar inclination cannot be maintained. We find that for magma ocean lifetimes of 10 Myr or more, the Earth's tidal quality factor Q must have been >300 to maintain primordial inclination, implying an early Earth 1-2 orders of magnitude less dissipative than at present. On the other hand, if tidal dissipation on the early Earth was stronger, our model implies rapid damping of the lunar inclination and requires subsequent late excitation of the lunar orbit after the crystallization of the lunar magma ocean.

  8. Earth 616, Earth 1610, Earth 3490—Wait, what universe is this again? The creation and evolution of the Avengers and Captain America/Iron Man fandom

    Directory of Open Access Journals (Sweden)

    Catherine Coker

    2013-06-01

    Full Text Available This essay surveys the creation and evolution of the Captain America/Iron Man or Steve/Tony ship in Avengers fandom, from its origin in comics to its reinterpretation by fandom through the recent movies, and discusses how the alternate universe trope in both canon and fanon is used to make a case for the pairing.

  9. Prescription Drug Profiles PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Prescription Drug Profiles Public Use Files (PUFs) drawn from Medicare prescription drug claims for the year of the date on which the...

  10. Prescription Drug Abuse

    Science.gov (United States)

    ... what the doctor prescribed, it is called prescription drug abuse. It could be Taking a medicine that ... purpose, such as getting high Abusing some prescription drugs can lead to addiction. These include opioids, sedatives, ...

  11. Microbes, Mineral Evolution, and the Rise of Microcontinents-Origin and Coevolution of Life with Early Earth.

    Science.gov (United States)

    Grosch, Eugene G; Hazen, Robert M

    2015-10-01

    Earth is the most mineralogically diverse planet in our solar system, the direct consequence of a coevolving geosphere and biosphere. We consider the possibility that a microbial biosphere originated and thrived in the early Hadean-Archean Earth subseafloor environment, with fundamental consequences for the complex evolution and habitability of our planet. In this hypothesis paper, we explore possible venues for the origin of life and the direct consequences of microbially mediated, low-temperature hydrothermal alteration of the early oceanic lithosphere. We hypothesize that subsurface fluid-rock-microbe interactions resulted in more efficient hydration of the early oceanic crust, which in turn promoted bulk melting to produce the first evolved fragments of felsic crust. These evolved magmas most likely included sialic or tonalitic sheets, felsic volcaniclastics, and minor rhyolitic intrusions emplaced in an Iceland-type extensional setting as the earliest microcontinents. With the further development of proto-tectonic processes, these buoyant felsic crustal fragments formed the nucleus of intra-oceanic tonalite-trondhjemite-granitoid (TTG) island arcs. Thus microbes, by facilitating extensive hydrothermal alteration of the earliest oceanic crust through bioalteration, promoted mineral diversification and may have been early architects of surface environments and microcontinents on young Earth. We explore how the possible onset of subseafloor fluid-rock-microbe interactions on early Earth accelerated metavolcanic clay mineral formation, crustal melting, and subsequent metamorphic mineral evolution. We also consider environmental factors supporting this earliest step in geosphere-biosphere coevolution and the implications for habitability and mineral evolution on other rocky planets, such as Mars.

  12. Geochemistry of U and Th and its Influence on the Origin and Evolution of the Crust of Earth and the Biological Evolution

    CERN Document Server

    Bao, Xuezhao

    1998-01-01

    We have investigated the migration behaviors of uranium (U) and thorium (Th) in the Earth and other terrestrial planets. Theoretical models of U and Th migration have been proposed. These models suggest that the unique features of the Earth are closely connected with its unique U and Th migration models and distribution patterns. In the Earth, U and Th can combine with oxidative volatile components and water, migrate up to the asthenosphere position to form an enrichment zone (EZ) of U and Th first, and then migrate up further to the crusts through magmatism and metamorphism. We emphasize that the formation of an EZ of U, Th and other heat-producing elements is a prerequisite for the formation of a plate tectonic system. The heat-producing elements, currently mainly U and Th, in the EZ are also the energy sources that drive the formation and evolution of the crust of Earth and create special granitic continental crusts. In other terrestrial planets, including Mercury, Venus, and Mars, an EZ can not be formed ...

  13. Evolution Inclusions and Variation Inequalities for Earth Data Processing II Differential-operator Inclusions and Evolution Variation Inequalities for Earth Data Processing

    CERN Document Server

    Zgurovsky, Mikhail Z; Kasyanov, Pavlo O

    2011-01-01

    Here, the authors present modern mathematical methods to solve problems of differential-operator inclusions and evolution variation inequalities which may occur in fields such as geophysics, aerohydrodynamics, or fluid dynamics. For the first time, they describe the detailed generalization of various approaches to the analysis of fundamentally nonlinear models and provide a toolbox of mathematical equations. These new mathematical methods can be applied to a broad spectrum of problems. Examples of these are phase changes, diffusion of electromagnetic, acoustic, vibro-, hydro- and seismoacousti

  14. On mega-undations: A new model for the earth's evolution

    NARCIS (Netherlands)

    Bemmelen, R.W. van

    Two fundamentally different views on the origin of the sialic crust of the earth are possible. According to one view the sialic crust has been produced from the inside by progressive physico-chemical differentiation of the earth's material into concentric spheres. Such an endogenic origin of the

  15. On mega-undations: A new model for the earth's evolution

    NARCIS (Netherlands)

    Bemmelen, R.W. van

    1966-01-01

    Two fundamentally different views on the origin of the sialic crust of the earth are possible. According to one view the sialic crust has been produced from the inside by progressive physico-chemical differentiation of the earth's material into concentric spheres. Such an endogenic origin of the cru

  16. Clues on the importance of comets in the origin and evolution of the atmospheres of Titan and Earth

    CERN Document Server

    Trigo-Rodriguez, Josep M

    2011-01-01

    Earth and Titan are two planetary bodies formed far from each other. Nevertheless the chemical composition of their atmospheres exhibits common indications of being produced by the accretion, plus ulterior in-situ processing of cometary materials. This is remarkable because while the Earth formed in the inner part of the disk, presumably from the accretion of rocky planetesimals depleted in oxygen and exhibiting a chemical similitude with enstatite chondrites, Titan formed within Saturn's sub-nebula from oxygen- and volatile-rich bodies, called cometesimals. From a cosmochemical and astrobiological perspective the study of the H, C, N, and O isotopes on Earth and Titan could be the key to decipher the processes occurred in the early stages of formation of both planetary bodies. The main goal of this paper is to quantify the presumable ways of chemical evolution of both planetary bodies, in particular the abundance of CO and N2 in their early atmospheres. In order to do that the primeval atmospheres and evolut...

  17. Dynamical evolution of interplanetary dust particles trapped in Earth's horseshoe and quasi-satellite co-orbital resonance regions

    Science.gov (United States)

    Kortenkamp, Stephen J.

    2016-10-01

    We use numerical integrations to model the orbital evolution of IDPs decaying from the asteroid belt into the inner solar system under the influence of radiation pressure, Poynting-Roberston light drag, and solar wind drag. In our models the ratio of radiation pressure to solar gravity ranges from 0.0025 up to 0.02, corresponding to IDP diameters ranging from about 200 microns down to about 25 microns, respectively. In this size range nearly 100% of IDPs become temporarily trapped in mean-motion resonances just outside Earth's orbit. While trapped in these outer resonances the orbital eccentricities of IDPs significantly increases. This causes most IDPs to eventually escape the resonances, allowing their orbits to continue decaying inwards past 1 AU. We've shown previously (Kortenkamp, Icarus 226, 1550-1558, 2013) that significant fractions of IDPs in this size range can subsequently become trapped in Earth's co-orbital horseshoe and quasi-satellite resonance regions, with semi-major axes just inside of 1 AU. Here, we present new results on the long-term effects of Earth's varying orbital eccentricity and inclination on the trapping and evolution of these co-orbital IDPs.

  18. Evolution of Information Management at the GSFC Earth Sciences (GES) Data and Information Services Center (DISC): 2006-2007

    Science.gov (United States)

    Kempler, Steven; Lynnes, Christopher; Vollmer, Bruce; Alcott, Gary; Berrick, Stephen

    2009-01-01

    Increasingly sophisticated National Aeronautics and Space Administration (NASA) Earth science missions have driven their associated data and data management systems from providing simple point-to-point archiving and retrieval to performing user-responsive distributed multisensor information extraction. To fully maximize the use of remote-sensor-generated Earth science data, NASA recognized the need for data systems that provide data access and manipulation capabilities responsive to research brought forth by advancing scientific analysis and the need to maximize the use and usability of the data. The decision by NASA to purposely evolve the Earth Observing System Data and Information System (EOSDIS) at the Goddard Space Flight Center (GSFC) Earth Sciences (GES) Data and Information Services Center (DISC) and other information management facilities was timely and appropriate. The GES DISC evolution was focused on replacing the EOSDIS Core System (ECS) by reusing the In-house developed disk-based Simple, Scalable, Script-based Science Product Archive (S4PA) data management system and migrating data to the disk archives. Transition was completed in December 2007

  19. Global-scale modelling of melting and isotopic evolution of Earth's mantle: Melting modules for TERRA

    NARCIS (Netherlands)

    Van Heck, H.J.; Huw Davies, J.; Elliott, T.; Porcelli, D.

    2016-01-01

    Many outstanding problems in solid-Earth science relate to the geodynamical explanation of geochemical observations. Currently, extensive geochemical databases of surface observations exist, but satisfying explanations of underlying mantle processes are lacking. One way to address these problems is

  20. Evolution of marine and terrestrial geobiodiversity in the history of the earth

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    People have long been curious about the history of life on the earth-how many different species have existed, when they first occurred, how they evolved over geologic time, and how they reacted to major environmental crises.

  1. Analytic model for the long-term evolution of circular Earth satellite orbits including lunar node regression

    Science.gov (United States)

    Zhu, Ting-Lei; Zhao, Chang-Yin; Zhang, Ming-Jiang

    2017-04-01

    This paper aims to obtain an analytic approximation to the evolution of circular orbits governed by the Earth's J2 and the luni-solar gravitational perturbations. Assuming that the lunar orbital plane coincides with the ecliptic plane, Allan and Cook (Proc. R. Soc. A, Math. Phys. Eng. Sci. 280(1380):97, 1964) derived an analytic solution to the orbital plane evolution of circular orbits. Using their result as an intermediate solution, we establish an approximate analytic model with lunar orbital inclination and its node regression be taken into account. Finally, an approximate analytic expression is derived, which is accurate compared to the numerical results except for the resonant cases when the period of the reference orbit approximately equals the integer multiples (especially 1 or 2 times) of lunar node regression period.

  2. [I.P.P.B. therapy at home in chronic respiratory insufficiency in France. I. Survey method. Description of the prescribers. 1960-1977 prescription evolution (author's transl)].

    Science.gov (United States)

    Drouet, D; Kauffmann, F; Brille, D; Hatzfeld, C; Liot, F; Kompalitch, M

    1979-01-01

    In order to assess the usage of IPPB therapy at home in chronic respiratory insufficiency in France, a mail survey has been conducted among 2,062 chest physicians and physicians involved in intensive care. The response rate was 57%. Among those caring for chronic respiratory insufficient patients, 296, i.e. 38%, have prescribed IPPB to 3,778 patients from 1960 till 1977. A study among a sample of the non-spontaneous-responders allows the estimation of about 400 physicians who prescribed IPPB on the whole for France at this time. Those who prescribed, worked more often in hospital though 4% had only a private practice. Those involved in intensive care prescribed more often than the chest physicians (47% versus 37%). The development of this therapy was different according to the different regions in France. But, in a general way, the prescription of IPPB at home particularly spread out since 1975, 65% of all the prescriptions have been done in 1975, 76, 77.

  3. O aparelho pré-ajustado: sua evolução e suas prescrições The pre-adjusted appliance: evolution and prescriptions

    Directory of Open Access Journals (Sweden)

    Vicente de Sousa Brito Júnior

    2006-06-01

    Full Text Available Este trabalho revisou as prescrições de braquetes pré-ajustados existentes no mercado, abordando as variações dos valores de inclinação, angulação e rotação dentária. A revisão reporta desde a origem do conceito de uso de arcos retangulares em acessórios com secções retangulares até os atuais modelos de braquetes autoligados e outros braquetes com formatos diferenciados.This research intended to review all the available prescriptions of pre-adjusted orthodontic appliances in the market and to discuss the justification of the authors as to the prescribed angulation, inclination and rotation suggested. The review encompassed the rectangular wire application in Edgewise brackets, until the implementation of self ligation, and many other kinds of brackets with distinct shapes according to the utilized technique. It was clear the great variety of many orthodontic mechanotherapy and brackets prescriptions, demonstrating that Orthodontics is a science with many possible alternatives.

  4. NASA's Evolution to K(sub a)- Band Space Communications for Near-Earth Spacecraft

    Science.gov (United States)

    McCarthy, Kevin P.; Stocklin, Frank J.; Geldzahler, Barry J.; Friedman, Daniel E.; Celeste, Peter B.

    2010-01-01

    Over the next several years, NASA plans to launch multiple earth-science missions which will send data from low-Earth orbits to ground stations at 1-3 Gbps, to achieve data throughputs of 5-40 terabits per day. These transmission rates exceed the capabilities of S-band and X-band frequency allocations used for science probe downlinks in the past. Accordingly, NASA is exploring enhancements to its space communication capabilities to provide the Agency's first Ka-band architecture solution for next generation missions in the near-earth regime. This paper describes the proposed Ka-band solution's drivers and concept, constraints and analyses which shaped that concept, and expansibility for future needs

  5. Time-dependent heat transfer in the spherical Earth: Implications on the power and thermal evolution of the core

    Science.gov (United States)

    Hofmeister, A. M.; Criss, R. E.

    2015-12-01

    We quantitatively investigate the time-dependence of heat conduction for a post-core, spherical Earth that is not convecting, due to compositional layering, based on hundreds of measurements of thermal diffusivity (D) for insulators and metals. Consistency of our solutions for widely ranging input parameters indicates how additional heat transfer mechanisms (mantle magmatism and convection) affect thermal evolution of the core. We consider 1) interior starting temperatures (T) of 273-5000 K, which represent variations in primordial heat, 2) different distributions and decay of long-lived radioactive isotopes, 3) additional heat sources in the core (primordial or latent heat), and 4) variable depth-T dependence of D. Our new analytical solution for cooling of a constant D sphere validates our numerical results. The bottom line is that the thermally insulating nature of minerals, combined with constraints of spherical geometry, limits steep thermal gradients to the upper mantle, consistent with the short length scale (x ~700 km) of cooling over t = 4.5 Ga indicated by dimensional analysis [x2 ~ 4Dt], and with plate tectonics. Consequently, interior temperatures vary little so the core has remained hot and is possibly warming. Findings include: 1) Constant vs. variable D affects thermal profiles only in detail, with D for the metallic core being inconsequential. 2) The hottest zone in Earth may lie in the uppermost lower mantle; 3) Most radiogenic heat is released in Earth's outermost 1000 km thereby driving an active outer shell; 4) Earth's core is essentially isothermal and is thus best described by the liquid-solid phase boundary; 5) Deeply sequestered radioactivity or other heat will melt the core rather than by run the dynamo (note that the heat needed to have melted the outer core is 10% of radiogenic heat generated over Earth's history); 6) Inefficient cooling of an Earth-sized mass means that heat essentially remains where it is generated, until it is removed

  6. Inpatients’ medical prescription errors

    Directory of Open Access Journals (Sweden)

    Aline Melo Santos Silva

    2009-09-01

    Full Text Available Objective: To identify and quantify the most frequent prescription errors in inpatients’ medical prescriptions. Methods: A survey of prescription errors was performed in the inpatients’ medical prescriptions, from July 2008 to May 2009 for eight hours a day. Rresults: At total of 3,931 prescriptions was analyzed and 362 (9.2% prescription errors were found, which involved the healthcare team as a whole. Among the 16 types of errors detected in prescription, the most frequent occurrences were lack of information, such as dose (66 cases, 18.2% and administration route (26 cases, 7.2%; 45 cases (12.4% of wrong transcriptions to the information system; 30 cases (8.3% of duplicate drugs; doses higher than recommended (24 events, 6.6% and 29 cases (8.0% of prescriptions with indication but not specifying allergy. Cconclusion: Medication errors are a reality at hospitals. All healthcare professionals are responsible for the identification and prevention of these errors, each one in his/her own area. The pharmacist is an essential professional in the drug therapy process. All hospital organizations need a pharmacist team responsible for medical prescription analyses before preparation, dispensation and administration of drugs to inpatients. This study showed that the pharmacist improves the inpatient’s safety and success of prescribed therapy.

  7. Rubidium isotopes in primitive chondrites: Constraints on Earth's volatile element depletion and lead isotope evolution

    Science.gov (United States)

    Nebel, O.; Mezger, K.; van Westrenen, W.

    2011-05-01

    The bulk silicate Earth (BSE) shows substantial deficits in volatile elements compared to CI-chondrites and solar abundances. These deficits could be caused by pre-accretionary depletion in the solar nebula during condensation of solids, or by later heat-driven evaporation during collision of small bodies that later accreted to form the Earth. The latter is considered to result in isotope fractionation for elements with low condensation temperatures that correlates with the degree of depletion. Here, we report first high-precision isotope ratio measurements of the moderately volatile and lithophile trace element Rb. Data from seventeen chondrite meteorites show that their Rb isotope abundances are nearly indistinguishable from Earth, not deviating more than 1 per mil in their 87Rb/85Rb. The almost uniform solar system Rb isotope pool suggests incomplete condensation or evaporation in a single stage is unlikely to be the cause of the volatile element deficit of the Earth. As Rb and Pb have similar condensation temperatures, we use their different degrees of depletion in the BSE to address the mechanisms and timing of terrestrial volatile depletion. The Rb isotope data are consistent with a scenario in which the volatile budget of the Earth was generated by a mixture of a highly volatile-element depleted early Proto-Earth with undepleted material in the course of terrestrial accretion. Observed Pb and Rb abundances and U-Pb and Rb-Sr isotope systematics suggest that volatile addition occurred at approximately the same time at which last core-mantle equilibration was achieved. In line with previous suggestions, this last equilibration involved a second stage of Pb (but not Rb) depletion from the BSE. The timing of this second Pb loss event can be constrained to ~ 110 Ma after the start of the solar system. This model supports a scenario with core storage of Pb in the aftermath of a putative Moon forming giant impact that also delivered the bulk of the volatile

  8. THE PRECAMBRIAN HISTORY OF THE ORIGIN AND EVOLUTION OF THE SOLAR SYSTEM AND EARTH. PART 1

    Directory of Open Access Journals (Sweden)

    M. I. Kuz’min

    2015-09-01

    Full Text Available The paper provides a review of early stages of development the Solar System and the geological history of Earth with reference to the latest data on the origin of the Solar System and the formation of the first continental rocks and results of studies of zircon, the oldest mineral so far dated on Earth. The formation of the Solar System from a gas-and-dust nebula is estimated to have begun 4.568 billion years ago. Ice was formed 1.5 million years later; it concentrated at the periphery of the system and served as the material for the largest planets, Jupiter and Saturn. In the central areas of the system, asteroids with diameters of about 10 km were formed. Their small bodies were composed of the basic material of the solar nebula, as evidenced by carbonaceous chondrite, CI, which composition is similar to the composition of the Sun, with the exception of hydrogen, helium, and volatile components that served as the main material for peripheral planets of the Solar System. Due to collision and partial merger of such small bodies, the formation of embryos of the terrestrial planets was initiated. Gravity made such embryos to cluster into larger bodies. After 7 million years, large asteroids and planet Mars were formed. It took 11 million years to form Planet Earth with a mass of 63 %, and 30 million years to form 93 % of its mass. Almost from the beginning of the formation of the Earth, short-lived radionuclides, 26Al and 60Fe, caused warming up of the small planetary bodies which led to the formation of their cores. During the initial stages, small magma reservoirs were formed, and molten iron particles gathered in the centres of the planetary bodies. As suggested by the ratio of 182W/184W, the major part of the core was formed within 20 million years, while its full mass accumulated completely within the next 50 million years. In 30–40 million years after the creation of the Solar System, the Earth collided with a cosmic body which mass was

  9. The Landscape Evolution Observatory: A large-scale controllable infrastructure to study coupled Earth-surface processes

    Science.gov (United States)

    Pangle, Luke A.; DeLong, Stephen B.; Abramson, Nate; Adams, John; Barron-Gafford, Greg A.; Breshears, David D.; Brooks, Paul D.; Chorover, Jon; Dietrich, William E.; Dontsova, Katerina; Durcik, Matej; Espeleta, Javier; Ferre, T. P. A.; Ferriere, Regis; Henderson, Whitney; Hunt, Edward A.; Huxman, Travis E.; Millar, David; Murphy, Brendan; Niu, Guo-Yue; Pavao-Zuckerman, Mitch; Pelletier, Jon D.; Rasmussen, Craig; Ruiz, Joaquin; Saleska, Scott; Schaap, Marcel; Sibayan, Michael; Troch, Peter A.; Tuller, Markus; van Haren, Joost; Zeng, Xubin

    2015-09-01

    Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these significant ecosystem services, refining our understanding of how these functions are affected by landscape evolution, weather variability, and long-term climate change is imperative. In this paper we introduce the Landscape Evolution Observatory (LEO): a large-scale controllable infrastructure consisting of three replicated artificial landscapes (each 330 m2 surface area) within the climate-controlled Biosphere 2 facility in Arizona, USA. At LEO, experimental manipulation of rainfall, air temperature, relative humidity, and wind speed are possible at unprecedented scale. The Landscape Evolution Observatory was designed as a community resource to advance understanding of how topography, physical and chemical properties of soil, and biological communities coevolve, and how this coevolution affects water, carbon, and energy cycles at multiple spatial scales. With well-defined boundary conditions and an extensive network of sensors and samplers, LEO enables an iterative scientific approach that includes numerical model development and virtual experimentation, physical experimentation, data analysis, and model refinement. We plan to engage the broader scientific community through public dissemination of data from LEO, collaborative experimental design, and community-based model development.

  10. The Landscape Evolution Observatory: a large-scale controllable infrastructure to study coupled Earth-surface processes

    Science.gov (United States)

    Pangle, Luke A.; DeLong, Stephen B.; Abramson, Nate; Adams, John; Barron-Gafford, Greg A.; Breshears, David D.; Brooks, Paul D.; Chorover, Jon; Dietrich, William E.; Dontsova, Katerina; Durcik, Matej; Espeleta, Javier; Ferre, T. P. A.; Ferriere, Regis; Henderson, Whitney; Hunt, Edward A.; Huxman, Travis E.; Millar, David; Murphy, Brendan; Niu, Guo-Yue; Pavao-Zuckerman, Mitch; Pelletier, Jon D.; Rasmussen, Craig; Ruiz, Joaquin; Saleska, Scott; Schaap, Marcel; Sibayan, Michael; Troch, Peter A.; Tuller, Markus; van Haren, Joost; Zeng, Xubin

    2015-01-01

    Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these significant ecosystem services, refining our understanding of how these functions are affected by landscape evolution, weather variability, and long-term climate change is imperative. In this paper we introduce the Landscape Evolution Observatory (LEO): a large-scale controllable infrastructure consisting of three replicated artificial landscapes (each 330 m2 surface area) within the climate-controlled Biosphere 2 facility in Arizona, USA. At LEO, experimental manipulation of rainfall, air temperature, relative humidity, and wind speed are possible at unprecedented scale. The Landscape Evolution Observatory was designed as a community resource to advance understanding of how topography, physical and chemical properties of soil, and biological communities coevolve, and how this coevolution affects water, carbon, and energy cycles at multiple spatial scales. With well-defined boundary conditions and an extensive network of sensors and samplers, LEO enables an iterative scientific approach that includes numerical model development and virtual experimentation, physical experimentation, data analysis, and model refinement. We plan to engage the broader scientific community through public dissemination of data from LEO, collaborative experimental design, and community-based model development.

  11. How Irreversible Heat Transport Processes Drive Earth's Interdependent Thermal, Structural, and Chemical Evolution Providing a Strongly Heterogeneous, Layered Mantle

    Science.gov (United States)

    Hofmeister, A.; Criss, R. E.

    2013-12-01

    Because magmatism conveys radioactive isotopes plus latent heat rapidly upwards while advecting heat, this process links and controls the thermal and chemical evolution of Earth. We present evidence that the lower mantle-upper mantle boundary is a profound chemical discontinuity, leading to observed heterogeneities in the outermost layers that can be directly sampled, and construct an alternative view of Earth's internal workings. Earth's beginning involved cooling via explosive outgassing of substantial ice (mainly CO) buried with dust during accretion. High carbon content is expected from Solar abundances and ice in comets. Reaction of CO with metal provided a carbide-rich core while converting MgSiO3 to olivine via oxidizing reactions. Because thermodynamic law (and buoyancy of hot particles) indicates that primordial heat from gravitational segregation is neither large nor carried downwards, whereas differentiation forced radioactive elements upwards, formation of the core and lower mantle greatly cooled the Earth. Reference conductive geotherms, calculated using accurate and new thermal diffusivity data, require that heat-producing elements are sequestered above 670 km which limits convection to the upper mantle. These irreversible beginnings limit secular cooling to radioactive wind-down, permiting deduction of Earth's inventory of heat-producing elements from today's heat flux. Coupling our estimate for heat producing elements with meteoritic data indicates that Earth's oxide content has been underestimated. Density sorting segregated a Si-rich, peridotitic upper mantle from a refractory, oxide lower mantle with high Ca, Al and Ti contents, consistent with diamond inclusion mineralogy. Early and rapid differentiation means that internal temperatures have long been buffered by freezing of the inner core, allowing survival of crust as old as ca.4 Ga. Magmatism remains important. Melt escaping though stress-induced fractures in the rigid lithosphere imparts a

  12. Evolution of Mg-5Al-0.4Mn microstructure after rare earth elements addition

    Directory of Open Access Journals (Sweden)

    A. Żydek

    2011-04-01

    Full Text Available Mg-5Al-0.4Mn-xRE (x = 0, 1, 2, 3 wt.% magnesium alloys were prepared successfully by casting method. The microstructure wasinvestigated by light microscopy. The influence of rare earth (RE elements on the area fraction of eutectic was analysed. The obtainedresults revealed that the as-cast Mg-5Al-0.4Mn alloy consist of α - Mg matrix and eutectic α + γ (where γ is Mg17Al12. However, whilerare earth elements were added to the Mg-Al type alloy, Al11RE3 precipitates were formed. The amount of the Al11RE3 precipitatesincreased with increasing addition of RE, but the amount of γ - Mg17Al12 decreased.

  13. Evolution of planetary cores and the Earth-Moon system from Nb/Ta systematics.

    Science.gov (United States)

    Münker, Carsten; Pfänder, Jörg A; Weyer, Stefan; Büchl, Anette; Kleine, Thorsten; Mezger, Klaus

    2003-07-04

    It has been assumed that Nb and Ta are not fractionated during differentiation processes on terrestrial planets and that both elements are lithophile. High-precision measurements of Nb/Ta and Zr/Hf reveal that Nb is moderately siderophile at high pressures. Nb/Ta values in the bulk silicate Earth (14.0 +/- 0.3) and the Moon (17.0 +/- 0.8) are below the chondritic ratio of 19.9 +/- 0.6, in contrast to Mars and asteroids. The lunar Nb/Ta constrains the mass fraction of impactor material in the Moon to less than 65%. Moreover, the Moon-forming impact can be linked in time with the final core-mantle equilibration on Earth 4.533 billion years ago.

  14. Evolution of the Oxidation State of the Earth's Mantle: Challenges of High Pressure Quenching

    Science.gov (United States)

    Danielson, L. R.; Righter, K.; Keller, L.; Christoffersen, R.; Rahman, Z.

    2015-01-01

    The oxidation state of the Earth's mantle during formation remains an unresolved question, whether it was constant throughout planetary accretion, transitioned from reduced to oxidized, or from oxidized to reduced. We investigate the stability of Fe3+ at depth, in order to constrain processes (water, late accretion, dissociation of FeO) which may reduce or oxidize the Earth's mantle. Experiments of more mafic compositions and at higher pressures commonly form a polyphase quench intergrowth composed primarily of pyroxenes, with interstitial glass which hosts nearly all of the more volatile minor elements. In our previous experiments on shergottite compositions, variable fO2, T, and P is less than 4 GPa, Fe3+/TotFe decreased slightly with increasing P, similar to terrestrial basalt. For oxidizing experiments less than 7GPa, Fe3+/TotFe decreased as well, but it's unclear from previous modelling whether the deeper mantle could retain significant Fe3+. Our current experiments expand our pressure range deeper into the Earth's mantle and focus on compositions and conditions relevant to the early Earth. Experiments with Knippa basalt as the starting composition were conducted at 1-8 GPa and 1800 C, using a molybdenum capsule to set the fO2 near IW, by buffering with Mo-MoO3. TEM and EELS analyses revealed the run products from 7-8 GPa quenched to polycrystalline phases, with the major phase pyroxene containing approximately equal Fe3+/2+. A number of different approaches have been employed to produce glassy samples that can be measured by EELS and XANES. A more intermediate andesite was used in one experiment, and decompression during quenching was attempted after, but both resulted in a finer grained polyphase texture. Experiments are currently underway to test different capsule materials may affect quench texture. A preliminary experiment using liquid nitrogen to greatly enhance the rate of cooling of the assembly has also been attempted and this technique will be

  15. NASA's Evolution to Ka-Band Space Communications for Near-Earth Spacecraft

    Science.gov (United States)

    McCarthy, Kevin; Stocklin, Frank; Geldzahler, Barry; Friedman, Daniel; Celeste, Peter

    2010-01-01

    This slide presentation reviews the exploration of NASA using a Ka-band system for spacecraft communications in Near-Earth orbits. The reasons for changing to Ka-band are the higher data rates, and the current (X-band spectrum) is becoming crowded. This will require some modification to the current ground station antennas systems. The results of a Request for Information (RFI) are discussed, and the recommended solution is reviewed.

  16. Weathering Pathways and Limitations in Biogeochemical Models: Application to Earth System Evolution

    OpenAIRE

    Mills, Benjamin

    2012-01-01

    Current biogeochemical box models for Phanerozoic climate are reviewed and reduced to a robust, modular system, allowing application to the Precambrian. It is shown that stabilisation of climate following a Neoproterozoic snowball Earth should take more than 10(7) years, due to long-term geological limitation of global weathering rates. The timescale matches the observed gaps between extreme glaciations at this time, suggesting that the late Neoproterozoic system was oscillating around a s...

  17. A planetary perspective on Earth evolution: Lid Tectonics before Plate Tectonics

    Science.gov (United States)

    Piper, John D. A.

    2013-03-01

    Plate Tectonics requires a specific range of thermal, fluid and compositional conditions before it will operate to mobilise planetary lithospheres. The response to interior heat dispersion ranges from mobile lids in constant motion able to generate zones of subduction and spreading (Plate Tectonics), through styles of Lid Tectonics expressed by stagnant lids punctured by volcanism, to lids alternating between static and mobile. The palaeomagnetic record through Earth history provides a test for tectonic style because a mobile Earth of multiple continents is recorded by diverse apparent polar wander paths, whilst Lid Tectonics is recorded by conformity to a single position. The former is difficult to isolate without extreme selection whereas the latter is a demanding requirement and easily recognised. In the event, the Precambrian palaeomagnetic database closely conforms to this latter property over very long periods of time (~ 2.7-2.2 Ga, 1.5-1.3 Ga and 0.75-0.6 Ga); intervening intervals are characterised by focussed loops compatible with episodes of true polar wander stimulated by disturbances to the planetary figure. Because of this singular property, the Precambrian palaeomagnetic record is highly effective in showing that a dominant Lid Tectonics operated throughout most of Earth history. A continental lid comprising at least 60% of the present continental area and volume had achieved quasi-integrity by 2.7 Ga. Reconfiguration of mantle and continental lid at ~ 2.2 Ga correlates with isotopic signatures and the Great Oxygenation Event and is the closest analogy in Earth history to the resurfacing of Venus. Change from Lid Tectonics to Plate Tectonics is transitional and the geological record identifies incipient development of Plate Tectonics on an orogenic scale especially after 1.1 Ga, but only following break-up of the continental lid (Palaeopangaea) in Ediacaran times beginning at ~ 0.6 Ga has it become comprehensive in the style evident during the

  18. Changes in the manner of tectonic movements under the Earth's evolution

    Science.gov (United States)

    Kuzmin, M. I.; Yarmolyuk, V. V.

    2016-08-01

    Variations in the O, Sr, Nd, and Hf isotopic compositions in rocks of various ages, minerals, and mantle temperature in the geological history are considered. Two periods in the Earth's history are studied: the beginning of the formation of the planet until the turn of (3.4) 2.7-2.5 Ga and the tectonic movement period in the last 2 Ga, and also the transitional period within 2.7-2.0 Ga.

  19. Evolution of the Earth and Origin of Life: The Role of Gas/Fluid Interactions with Rocks

    Science.gov (United States)

    Freund, Friedemann

    2001-01-01

    The work under the Cooperative Agreement will be centered on questions of the evolution of Life on the early Earth and possibly on Mars. It is still hotly debated whether the essential organic molecules were delivered to the early Earth from space (by comets, meteorites or interplanetary dust particles) or were generated in situ on Earth. Prior work that has shown that the matrix of igneous minerals is a medium in which progenitors of organic molecules assemble from H2O, C02 and N2 incorporated as minority "impurities" in minerals of igneous rocks during crystallization from H2O/CO2/N2-laden magmas. The underlying processes involve a redox. conversion whereby C, H, and N become chemically reduced, while 0 becomes oxidized to the peroxy state. During Year 02 the work will be divided into three tasks. Task 1: After carboxylic (fatty) acids and N-bearing compounds have been identified, other extractable organic molecules including lipids, oily substances and amino acids will be studied. Dedicated lipid analysis will be combined with gas chromatographic-mass spectroscopic (GCMS) analysis of organic compounds extracted from minerals and rocks. Task 2: Using infrared (IR) spectroscopy, C-H entities that are indicators for the organic progenitors in mineral matrices will be studied. A preliminary heating experiment with MgO single crystals has shown that the C-H entities can be pyrolyzed, causing the IR bands to disappear, but at room temperature the IR bands reappear in a matter of days to weeks. This work will be expanded, both by studying synthetic MgO crystals and olivine crystals from the Earth's upper mantle. The C-H bands will be compared to the published "organic" IR feature of dust in the interstellar medium (ISM) and interplanetary dust particles (IDP). Task 3: A paradox marks the evolution of early Life: Oxygen is highly toxic to primitive life, yet early organisms "learned" to detoxify reactive oxygen species, to utilize oxygen, and even produce it. Why would

  20. Symbiosis in cell evolution: Life and its environment on the early earth

    Science.gov (United States)

    Margulis, L.

    1981-01-01

    The book treats cell evolution from the viewpoint of the serial endosymbiosis theory of the origin of organelles. Following a brief outline of the symbiotic theory, which holds that eukaryotes evolved by the association of free-living bacteria with a host prokaryote, the diversity of life is considered, and five kingdoms of organisms are distinguished: the prokaryotic Monera and the eukaryotic Protoctista, Animalia, Fungi and Plantae. Symbiotic and traditional direct filiation theories of cell evolution are compared. Recent observations of cell structure and biochemistry are reviewed in relation to early cell evolution, with attention given to the geological context for the origin of eukaryotic cells, the origin of major bacterial anaerobic pathways, the relationship between aerobic metabolism and atmospheric oxygen, criteria for distinguishing symbiotic organelles from those that originated by differentiation, and the major classes of eukaryotic organelles: mitochondria, cilia, microtubules, the mitotic and meiotic apparatuses, and pastids. Cell evolution during the Phanerozoic is also discussed with emphasis on the effects of life on the biosphere

  1. Titration of the Earth: Ocean-Atmosphere Evolution Recorded in Marine Carbonates

    Science.gov (United States)

    Kah, L. C.

    2012-12-01

    The enzymatic production of carbonate biominerals marks a clear association between biological processes and carbonate mineral formation. Prior to the evolution of skeletonizing metazoans, however, biotic activity played a less critical role in the morphological development of carbonate minerals. Instead, carbonate mineral morphology was more strongly affected by abiotic parameters that affect carbonate nucleation and growth. The texture of non-enzymatically controlled carbonate precipitation in the Precambrian may therefore provide us with an additional window through which to observe fundamental changes in the chemical evolution of the global ocean. The Precambrian ocean experienced a progressive evolution from CO2-rich and O2-poor, to CO2-poor and O2-rich. Changes in CO2-availability fundamentally affect marine carbonate saturation state, which is reflected primarily in the rate of crystal growth. By contrast, redox evolution appears to have played a fundamental role in regulating carbonate precipitation via the differential inhibition of mineral nucleation. Carbonate mineral textures that indicate differential nucleation and growth can be traced both spatially and temporally in the Precambrian sedimentary record. Textures that are dominated by high rates of growth relative to nucleation are common in Archean, and become progressively restricted in their distribution by the latter Proterozoic. Spatial restriction, particularly of fabrics associated with redox-controlled nucleation, suggesting the development of chemically discrete oceanic environments. Such observations are consistent with recent models of suggesting that ocean oxygenation occurred in a top-down fashion, with well-oxygenated surface waters underlain by either anoxic deep-waters or oxygen-depleted substrate pore-waters. Deciphering relationships among these environments permits attribution of carbonate fabrics to specific geochemical conditions within the water column and provides critical

  2. Evolution of the Oxidation State of the Earth's Mantle: Challenges of High Pressure Quenching

    Science.gov (United States)

    Danielson, L. R.; Righter, K.; Keller, L. P.; Rahman, Z.

    2015-12-01

    The oxidation state of the Earth's mantle during formation remains an unresolved question, whether it was constant throughout planetary accretion [1], transitioned from reduced to oxidized [2,3,4], or from oxidized to reduced [1,5]. We investigate the stability of Fe3+ at depth, in order to constrain processes (water, late accretion, dissociation of FeO) which may reduce or oxidize the Earth's mantle. Experiments of more mafic compositions and at higher pressures commonly form a polyphase quench intergrowth composed primarily of pyroxenes, with interstitial glass which hosts nearly all of the more volatile minor elements. In our previous experiments on shergottite compositions, variable fO2, T, and P <4 GPa, Fe3+/ΣFe decreased slightly with increasing P, similar to terrestrial basalt [6,7,8]. For oxidizing experiments < 7GPa, Fe3+/ΣFe decreased as well [9], but it's unclear from previous modelling whether the deeper mantle could retain significant Fe3+ [1,10]. Our current experiments expand our pressure range deeper into the Earth's mantle and focus on compositions and conditions relevant to the early Earth. Experiments with Knippa basalt as the starting composition were conducted at 1-8 GPa and 1800 °C, using a molybdenum capsule to set the fO2 near IW, by buffering with Mo-MoO3. TEM and EELS analyses revealed the run products from 7-8 GPa quenched to polycrystalline phases, with the major phase pyroxene containing approximately equal Fe3+/2+. A number of different approaches have been employed to produce glassy samples that can be measured by EELS and XANES. A more intermediate andesite was used in one experiment, and decompression during quenching was attempted after [11], but both resulted in a finer grained polyphase texture. Experiments are currently underway to test how different capsule materials may affect quench texture. A preliminary experiment using liquid nitrogen to greatly enhance the rate of cooling of the assembly has also been attempted and

  3. Life: Origin and evolution on Earth--How can we escape?

    Science.gov (United States)

    Markert, Clement L.; Krikorian, Abraham D.

    1993-01-01

    Exploitation of gene regulation rather than the creation of new genes has been predominantly responsible for the evolutionary advances in animals and plants that are widely recognized today. Until very recently it was not possible to examine life in the absence of gravity. We can now imagine forms of life in the universe adapting to circumstances different from those found on Earth. Our own life forms would surely become different in time if they were transferred to other planets with different conditions, including much lower or higher gravity.

  4. Hybrid Differential Evolution Optimisation for Earth Observation Satellite Scheduling with Time-Dependent Earliness-Tardiness Penalties

    Directory of Open Access Journals (Sweden)

    Guoliang Li

    2017-01-01

    Full Text Available We study the order acceptance and scheduling (OAS problem with time-dependent earliness-tardiness penalties in a single agile earth observation satellite environment where orders are defined by their release dates, available processing time windows ranging from earliest start date to deadline, processing times, due dates, sequence-dependent setup times, and revenues. The objective is to maximise total revenue, where the revenue from an order is a piecewise linear function of its earliness and tardiness with reference to its due date. We formulate this problem as a mixed integer linear programming model and develop a novel hybrid differential evolution (DE algorithm under self-adaptation framework to solve this problem. Compared with classical DE, hybrid DE employs two mutation operations, scaling factor adaptation and crossover probability adaptation. Computational tests indicate that the proposed algorithm outperforms classical DE in addition to two other variants of DE.

  5. Is lithostatic loading important for the slip behavior and evolution of normal faults in the Earth's crust?

    Energy Technology Data Exchange (ETDEWEB)

    Kattenhorn, Simon A. [Department of Geological and Environmental Sciences, Stanford University, Stanford, California (United States); Pollard, David D. [Department of Geological and Environmental Sciences, Stanford University, Stanford, California (United States)

    1999-12-10

    Normal faults growing in the Earth's crust are subject to the effects of an increasing frictional resistance to slip caused by the increasing lithostatic load with depth. We use three-dimensional (3-D) boundary element method numerical models to evaluate these effects on planar normal faults with variable elliptical tip line shapes in an elastic solid. As a result of increasing friction with depth, normal fault slip maxima for a single slip event are skewed away from the fault center toward the upper fault tip. There is a correspondingly greater propagation tendency at the upper tip. However, the tall faults that would result from such a propagation tendency are generally not observed in nature. We show how mechanical interaction between laterally stepping fault segments significantly competes with the lithostatic loading effect in the evolution of a normal fault system, promoting lateral propagation and possibly segment linkage. Resultant composite faults are wider than they are tall, resembling both 3-D seismic data interpretations and previously documented characteristics of normal fault systems. However, this effect may be greatly complemented by the influence of a heterogeneous stratigraphy, which can control fault nucleation depth and inhibit fault propagation across the mechanical layering. Our models demonstrate that although lithostatic loading may be an important control on fault evolution in relatively homogeneous rocks, the contribution of lithologic influences and mechanical interaction between closely spaced, laterally stepping faults may predominate in determining the slip behavior and propagation tendency of normal faults in the Earth's crust. (c) 1999 American Geophysical Union.

  6. Deep mantle heat flow and thermal evolution of the Earth's core based on thermo-chemical mantle convection

    Science.gov (United States)

    Nakagawa, T.; Tackley, P.; Buffett, B.

    2004-12-01

    A coupled core-mantle evolution model that combines the global heat balance in the core with a fully-dynamical thermo-chemical mantle convection [Nakagawa and Tackley, 2004 published in EPSL] is used to investigate the deep mantle heat flow that is required to sustain the magnetic field generated by the geodynamo process. Effects of a radioactive heat source due to potassium in the core are also included in the global heat balance in the Earth??s core. Two important parameters are checked in this study; (1) density variation between depleted hartzbergite and basaltic material (0 to 3 percent) and (2) concentration of radioactive potassium in the core alloy (0ppm to 400ppm). The parameter set that most closely satisfies the criteria of size of the inner core (1220km at present time) is around 2 percent of density difference in a convecting mantle and 200ppm of radioactive heat source in the core. The concentration of potassium in the core is consistent with the geochemical approach [Murthy et al., 2003] but smaller than other successful thermal evolution models [Labrosse, 2003; Nimmo et al., 2004]. Heat flow through the core-mantle boundary and the contribution of radioactive heat sources in the core are consistent with theoretical estimates [e.g. Buffett, 2002] and geochemical constraints [Gessmann and Wood, 2002]. The power available to the geodynamo, based on the predicted heat flow through the core-mantle boundary, is approximately four times greater than the value predicted by numerical models of the geodynamo [Christensen and Kutzner, 2004] but closer to theoretical estimates [e.g. Buffett, 2002].

  7. Properties and evolution of NEO families created by tidal disruption at Earth

    CERN Document Server

    Schunová, Eva; Walsh, Kevin J; Granvik, Mikael; Wainscoat, Richard J; Haghighipour, Nader

    2014-01-01

    We have calculated the coherence and detectable lifetimes of synthetic near-Earth object (NEO) families created by catastrophic disruption of a progenitor as it suffers a very close Earth approach. The closest or slowest approaches yield the most violent `s-class' disruption events. We found that the average slope of the absolute magnitude (H) distribution, $N(H)\\propto10^{(0.55\\pm0.04)\\,H}$, for the fragments in the s-class families is steeper than the slope of the NEO population \\citep{mainzer2011} in the same size range. The families remain coherent as statistically significant clusters of orbits within the NEO population for an average of $\\bar\\tau_c = (14.7\\pm0.6)\\times10^3$ years after disruption. The s-class families are detectable with the techniques developed by \\citet{fu2005} and \\citet{Schunova2012} for an average duration ($\\bar\\tau_{det}$) ranging from about 2,000 to about 12,000 years for progenitors in the absolute magnitude ($H_p$) range from 20 to 13 corresponding to diameters in the range fr...

  8. The evolution of Earth Observation satellites in Europe and its impact on the performance of emergency response services

    Science.gov (United States)

    Denis, Gil; de Boissezon, Hélène; Hosford, Steven; Pasco, Xavier; Montfort, Bruno; Ranera, Franck

    2016-10-01

    The paper reviews the evolution of Earth Observation systems in Europe and Worldwide and analyses the potential impact of their performance in support of emergency response services. Earth Observation satellites play already a significant role in supporting the action of first responders in case of major disasters. The main principle is the coordinated use of satellites in order to ensure a rapid response and the timely delivery of images and geospatial information of the area affected by the event. The first part of the paper reviews the main instruments and evaluates their current performance. The International Charter "Space and Major Disasters", signed in October 2000, was the first international initiative aimed at establishing a unified system for the acquisition of space data. The charter is a cooperation agreement between space agencies and operators of space systems. At regional level, a similar instrument exists in Asia: Sentinel-Asia. In the frame of the European programme Copernicus, the emergency management service was launched in 2009. Geo-information products derived from space imagery are delivered during all phases of the emergency management cycle, in either rush or non-rush mode, free of charge for the users. In both cases, the capacities were historically drawn from national missions, funded with public money and directly operated by the space agencies or by national operators.

  9. Nonlinear evolution of mirror instability in the Earth's magnetosheath in pic simulations

    Science.gov (United States)

    Ahmadi, Narges

    Mirror modes are large amplitude non-propagating structures frequently observed in the magnetosheath and they are generated in space plasma environments with proton temperature anisotropy of larger than one. The proton temperature anisotropy also drives the proton cyclotron instability which has larger linear growth rate than that of the mirror instability. Linear dispersion theory predicts that electron temperature anisotropy can enhance the mirror instability growth rate while leaving the proton cyclotron instability largely unaffected. Contrary to the hypothesis, electron temperature anisotropy leads to excitement of the electron whistler instability. Our results show that the electron whistler instability grows much faster than the mirror instability and quickly consumes the electron free energy, so that there is not enough electron temperature anisotropy left to significantly impact the evolution of the mirror instability. Observational studies have shown that the shape of mirror structures is related to local plasma parameters and distance to the mirror instability threshold. Mirror structures in the form of magnetic holes are observed when plasma is mirror stable or marginally mirror unstable and magnetic peaks are observed when plasma is mirror unstable. Mirror structures are created downstream of the quasi-perpendicular bow shock and they are convected toward the magnetopause. In the middle magnetosheath, where plasma is mirror unstable, mirror structures are dominated by magnetic peaks. Close to the magnetopause, plasma expansion makes the region mirror stable and magnetic peaks evolve to magnetic holes. We investigate the nonlinear evolution of mirror instability using expanding box Particle-in-Cell simulations. We change the plasma conditions by artificially enlarging the simulation box over time to make the plasma mirror stable and investigate the final nonlinear state of the mirror structures. We show that the direct nonlinear evolution of the mirror

  10. The Near Earth Object Surveillance Satellite: Mission status and CCD evolution after 18 months on-orbit

    Science.gov (United States)

    Wallace, B.; Scott, R.; Sale, M.

    2014-09-01

    The Near Earth Object Surveillance Satellite (NEOSSat) is a small telescope equipped microsatellite designed to perform both Space Situational Awareness (SSA) experiments and asteroid detection. NEOSSat was launched on 25 February 2013, however, due to time pressures, NEOSSat was launched with only the minimal software required to keep the spacecraft safe. The time pressure also resulted in the spacecraft undergoing reduced system and environmental testing on the ground. The full software suite, required to obtain imagery and maintain stable pointing, has since been uploaded to the spacecraft. NEOSSat has obtained imagery since June 2013, with the shutter both open and closed, but as of March 2014 has not achieved the fine pointing required to obtain scientifically useful data. The collected imagery is being used to characterize the on-board CCD camera. While gain and dark current values agree with pre-launch values, unexpected artefacts have appeared in the images. Methods for mitigating the artefacts through image processing have been developed, and spacecraft-level fixes are currently being investigated. In addition, damage from high energy particles impacting the CCD has produced hot pixels in imagery. We have been able to measure the evolution of these hot pixels over several months, both in terms of numbers and characteristics; these results will be presented. In addition, early results from the mission (image quality issues and evolution, early imagery examples), as well as the mission status (including fine pointing), will be discussed.

  11. Highly stable evolution of Earth's future orbit despite chaotic behavior of the Solar System

    CERN Document Server

    Zeebe, Richard E

    2015-01-01

    Due to the chaotic nature of the Solar System, the question of its dynamic long-term stability can only be answered in a statistical sense, e.g. based on numerical ensemble integrations of nearby orbits. Destabilization, including catastrophic encounters and/or collisions involving the Earth, has been suggested to be initiated through a large increase in Mercury's eccentricity (eM), with an estimated probability of ~1%. However, it has recently been shown that the statistics of numerical Solar System integrations are sensitive to the accuracy and type of numerical algorithm. Here I report results from computationally demanding ensemble integrations (N=1,600 with slightly different initial conditions) at unprecedented accuracy based on the full equations of motion of the eight planets and Pluto over 5Gyr, including contributions from general relativity. The standard symplectic algorithm produced spurious results for highly eccentric orbits and during close encounters, which were hence integrated with a suitabl...

  12. Human factors dimensions in the evolution of increasingly automated control rooms for near-earth satellites

    Science.gov (United States)

    Mitchell, C. M.

    1982-01-01

    The NASA-Goddard Space Flight Center is responsible for the control and ground support for all of NASA's unmanned near-earth satellites. Traditionally, each satellite had its own dedicated mission operations room. In the mid-seventies, an integration of some of these dedicated facilities was begun with the primary objective to reduce costs. In this connection, the Multi-Satellite Operations Control Center (MSOCC) was designed. MSOCC represents currently a labor intensive operation. Recently, Goddard has become increasingly aware of human factors and human-machine interface issues. A summary is provided of some of the attempts to apply human factors considerations in the design of command and control environments. Current and future activities with respect to human factors and systems design are discussed, giving attention to the allocation of tasks between human and computer, and the interface for the human-computer dialogue.

  13. Human factors dimensions in the evolution of increasingly automated control rooms for near-earth satellites

    Science.gov (United States)

    Mitchell, C. M.

    1982-01-01

    The NASA-Goddard Space Flight Center is responsible for the control and ground support for all of NASA's unmanned near-earth satellites. Traditionally, each satellite had its own dedicated mission operations room. In the mid-seventies, an integration of some of these dedicated facilities was begun with the primary objective to reduce costs. In this connection, the Multi-Satellite Operations Control Center (MSOCC) was designed. MSOCC represents currently a labor intensive operation. Recently, Goddard has become increasingly aware of human factors and human-machine interface issues. A summary is provided of some of the attempts to apply human factors considerations in the design of command and control environments. Current and future activities with respect to human factors and systems design are discussed, giving attention to the allocation of tasks between human and computer, and the interface for the human-computer dialogue.

  14. 100th anniversary special paper: Sedimentary mineral deposits and the evolution of earth's near-surface environments

    Energy Technology Data Exchange (ETDEWEB)

    Holland, H.D. [Harvard University, Cambridge, MA (United States). Dept. of Earth & Planetary Science

    2005-12-15

    The nature of sedimentary mineral deposits has evolved during Earth's history in concert with changes in the oxidation (redo) state of the ocean-atmosphere system, biological evolution, and the growing importance of geologically young accumulations of ore-grade material. There is now strong evidence that the atmosphere and the oceans were anoxic, or essentially anoxic, before 2.4 Ga. Banded iron formations (BIF) and the detrital uranium ores formed prior to 2.4 Ga are consistent with such a state. The period between 2.4 and 2.0 Ga is called the Great Oxidation Event by some. Its ores bear unmistakable marks of the presence of atmospheric O{sub 2}. Between 1.8 and 0.8 Ga the Earth system seems to have been remarkably stable. Sedimentary ore deposits of this period were influenced by the presence of O{sub 2}. BIF, sedimentary manganese, and phosphorites disappeared ca. 1.8 Ga, but sedimentary exhalative (SEDEX) deposits and unconformity-type uranium deposits flourished, and nonsulfide zinc deposits put in an appearance. The period between 0.8 Ga and the end of the Proterozoic at 0.54 Ga was as turbulent or more so than the Paleoproterozoic. BIF returned, as did sedimentary manganese deposits and phosphorites. A further rise in the O{sub 2} content of the atmosphere and an increase in the sulfate concentration of seawater during this period brought the composition of the atmosphere and of seawater close to their present redox state. The last 540 m.y. of Earth's history have seen the system pass through two supercycles of roughly equal length. Climate, the redox stratification of the oceans ocean mixing, and the nature of sedimentary ores were influenced by tectonically and volcanically driven changes during these supercycles. The evolution of the higher land plants gave rise to coal deposits and sandstone-type uranium ores and was important for the formation of bauxites.

  15. Precambrian supercontinents, glaciations, atmospheric oxygenation, metazoan evolution and an impact that may have changed the second half of Earth history

    Directory of Open Access Journals (Sweden)

    Grant M. Young

    2013-05-01

    Full Text Available In more than 4 Ga of geological evolution, the Earth has twice gone through extreme climatic perturbations, when extensive glaciations occurred, together with alternating warm periods which were accompanied by atmospheric oxygenation. The younger of these two episodes of climatic oscillation preceded the Cambrian “explosion” of metazoan life forms, but similar extreme climatic conditions existed between about 2.4 and 2.2 Ga. Over long time periods, changing solar luminosity and mantle temperatures have played important roles in regulating Earth's climate but both periods of climatic upheaval are associated with supercontinents. Enhanced weathering on the orogenically and thermally buoyed supercontinents would have stripped CO2 from the atmosphere, initiating a cooling trend that resulted in continental glaciation. Ice cover prevented weathering so that CO2 built up once more, causing collapse of the ice sheets and ushering in a warm climatic episode. This negative feedback loop provides a plausible explanation for multiple glaciations of the Early and Late Proterozoic, and their intimate association with sedimentary rocks formed in warm climates. Between each glacial cycle nutrients were flushed into world oceans, stimulating photosynthetic activity and causing oxygenation of the atmosphere. Accommodation for many ancient glacial deposits was provided by rifting but escape from the climatic cycle was predicated on break-up of the supercontinent, when flooded continental margins had a moderating influence on weathering. The geochemistry of Neoproterozoic cap carbonates carries a strong hydrothermal signal, suggesting that they precipitated from deep sea waters, overturned and spilled onto continental shelves at the termination of glaciations. Paleoproterozoic (Huronian carbonates of the Espanola Formation were probably formed as a result of ponding and evaporation in a hydrothermally influenced, restricted rift setting. Why did metazoan

  16. Texture evolution during thermomechanical processing in rare earth free magnesium alloys

    Science.gov (United States)

    Miller, Victoria Mayne

    The use of wrought magnesium alloys is highly desirable for a wide range of applications where low component weight is desirable due to the high specific strength and stiffness the alloys can achieve. However, the implementation of wrought magnesium has been hindered by the limited room temperature formability which typically results from deformation processing. This work identifies opportunities for texture modification during thermomechanical processing of conventional (rare earth free) magnesium alloys via a combination of experimental investigation and polycrystal plasticity simulations. During deformation, it is observed that a homogeneous distribution of coarse intermetallic particles efficiently weakens deformation texture at all strain levels, while a highly inhomogeneous particle distribution is only effective at high strains. The particle deformation effects are complemented by the addition of alkaline earth solute, which modifies the relative deformation mode activity. During recrystallization, grains with basal orientations recrystallize more readily than off-basal grains, despite similar levels of internal misorientation. Dislocation substructure investigations revealed that this is a result of enhanced nucleation in the basal grains due to the dominance of prismatic slip. This dissertation identifies avenues to enhance the potential formability of magnesium alloys during thermomechanical processing by minimizing the evolved texture strength. The following are the identified key aspects of microstructural control: -Maintaining a fine grain size, likely via Zener pinning, to favorably modify deformation mode activity and homogenize deformation. -Developing a coarse, homogeneously distributed population of coarse intermetallic particles to promote a diffuse deformation texture. -Minimizing the activity of prismatic slip to retard the recrystallization of grains with basal orientations, allowing the development of a more diffuse recrystallization texture.

  17. Status and Evolution of the Journal of Astronomy & Earth Science Education's First Year

    Science.gov (United States)

    Slater, Timothy F.

    2016-01-01

    The Journal of Astronomy & Earth Science Education (JAESE.org) is a recently created, peer-reviewed journal designed to serve the discipline-based astronomy, planetary, and geo-sciences education research community. JAESE's first issue was published on December 31, 2014 and has published two volumes and three issues since that time, encompassing 15 peer-reviewed articles. By far, the median article topic has been focused on planetarium education research, while there has only been one article on solid Earth geosciences education research. Although there is not yet an even distribution of topics across the field, there is a relatively even distribution among author demographics. Authors include a range of both junior and senior members of the field. There have been slightly female authors than male authors. Submissions are distributed to two or three reviewers with authors' names redacted from the manuscript. The average time to complete the first round of peer-review reviewers is 6.2-weeks. There have been too few manuscripts to reliably publish a "percentage acceptance rate." Finally, the majority of recently completed astronomy education research doctoral dissertations have been published in JAESE. Taken together, JAESE's guiding Editorial Advisory Board judges this to be a successful first year. In a purposeful effort to make JAESE authors' scholarly works as widely accessible as possible, JAESE adopted an open-access business model. JAESE articles are available to read free-of-charge over the Internet, delivered as PDFs. To date, the most common way articles are downloaded by readers is through Google Scholar. Instead of charging readers and libraries recurring subscription fees, JAESE charges authors a nominal submission fee and a small open-access fee, averaging about $500 USD. These charges are similar to the traditional page charges typically charged to authors or their institutions by scientific journals, making JAESE an attractive publishing venue for

  18. Getting a prescription filled

    Science.gov (United States)

    ... are located inside of a grocery or large "chain" store. It is best to fill all prescriptions ... be used for long-term medicines and medical supplies. The website should have clear directions for filling ...

  19. ON THE UNIQUENESS OF THE UNBOUNDED CLASSICAL SOULTION OF THE EVOLUTION SYSTEM DESCRIBING GEOPHYSICAL FLOW WITHIN THE EARTH AND ITS ASSOCIATED SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    李开泰; 赵春山

    2001-01-01

    The uniqueness for unbounded classical solutions of the evolution system describing geophysical flow within the earth and its associated systems is investigated. Under suitable growth conditions,it is shown that the solution to the initial value problem is unique. Moreover,a counterexample is given if the growth conditions are not satisfied.

  20. A new time tree reveals Earth history’s imprint on the evolution of modern birds

    Science.gov (United States)

    Claramunt, Santiago; Cracraft, Joel

    2015-01-01

    Determining the timing of diversification of modern birds has been difficult. We combined DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate a new time tree for Neornithes and investigated their biogeographic and diversification dynamics. We found that the most recent common ancestor of modern birds inhabited South America around 95 million years ago, but it was not until the Cretaceous-Paleogene transition (66 million years ago) that Neornithes began to diversify rapidly around the world. Birds used two main dispersion routes: reaching the Old World through North America, and reaching Australia and Zealandia through Antarctica. Net diversification rates increased during periods of global cooling, suggesting that fragmentation of tropical biomes stimulated speciation. Thus, we found pervasive evidence that avian evolution has been influenced by plate tectonics and environmental change, two basic features of Earth’s dynamics. PMID:26824065

  1. Prescription drug misuse.

    Science.gov (United States)

    Monheit, Benny

    2010-08-01

    Recognising and dealing with patients who seek drugs for nonmedical purposes can be a difficult problem in general practice. 'Prescription shoppers' and patients with chronic nonmalignant pain problems are the main people who constitute this small but problematic group. The main drugs they seek are benzodiazepines and opioids. To provide data on current trends in prescription drug abuse and to discuss different strategies on how to deal with this issue in the clinic setting. Misuse of prescription drugs can take the form of injecting oral drugs, selling them on the street, or simply overusing the prescribed amount so that patients run short before the due date and then request extra prescriptions from the doctor. Currently oxycontin and alprazolam are the most abused drugs in Australia. Adequate prescription monitoring mechanisms at the systems level are lacking so we need to rely on our clinical skills and the patient's behaviour pattern over time to detect problematic prescription drug misuse. Management strategies may include saying 'no' to patients, having a treatment plan, and adopting a universal precaution approach toward all patients prescribed drugs of addiction. Among patients with chronic nonmalignant pain, requests for increasing opioid doses need careful assessment to elucidate any nonmedical factors that may be at play.

  2. End products of cometary evolution - Cometary origin of earth-crossing bodies of asteroidal appearance

    Science.gov (United States)

    Wetherill, G. W.

    1991-01-01

    The present state of the understanding of the dynamic mechanisms under which the orbits of some comets evolve into those observed for Apollo-Amor objects is reviewed. Observed Jupiter-family objects of asteroidal appearance, e.g., 1983SA, are much more likely to be of cometary rather than asteroidal origin. 'Decoupling' is facilitated by several mechanisms: perturbations by terrestrial planets, perturbations by Jupiter and the other giant planets, and nongravitational orbital changes caused by the loss of gas and dust from the comet. The dynamical time scale for decoupling is argued to be 100,000-1,000,000 yr, and almost all decoupled comets are likely to be of asteroidal appearance. Estimates can be made of the number of cometary Apollo-Amor 'asteroids', the observed number of earth-crossing active and inactive short-period comets, and the production rate of short-period comets. These estimates are compatible with other theoretical and observational inferences that suggest the presence of a significant population of Apollo objects that formerly were active comets.

  3. The Public Goods Hypothesis for the evolution of life on Earth.

    Science.gov (United States)

    McInerney, James O; Pisani, Davide; Bapteste, Eric; O'Connell, Mary J

    2011-08-23

    It is becoming increasingly difficult to reconcile the observed extent of horizontal gene transfers with the central metaphor of a great tree uniting all evolving entities on the planet. In this manuscript we describe the Public Goods Hypothesis and show that it is appropriate in order to describe biological evolution on the planet. According to this hypothesis, nucleotide sequences (genes, promoters, exons, etc.) are simply seen as goods, passed from organism to organism through both vertical and horizontal transfer. Public goods sequences are defined by having the properties of being largely non-excludable (no organism can be effectively prevented from accessing these sequences) and non-rival (while such a sequence is being used by one organism it is also available for use by another organism). The universal nature of genetic systems ensures that such non-excludable sequences exist and non-excludability explains why we see a myriad of genes in different combinations in sequenced genomes. There are three features of the public goods hypothesis. Firstly, segments of DNA are seen as public goods, available for all organisms to integrate into their genomes. Secondly, we expect the evolution of mechanisms for DNA sharing and of defense mechanisms against DNA intrusion in genomes. Thirdly, we expect that we do not see a global tree-like pattern. Instead, we expect local tree-like patterns to emerge from the combination of a commonage of genes and vertical inheritance of genomes by cell division. Indeed, while genes are theoretically public goods, in reality, some genes are excludable, particularly, though not only, when they have variant genetic codes or behave as coalition or club goods, available for all organisms of a coalition to integrate into their genomes, and non-rival within the club. We view the Tree of Life hypothesis as a regionalized instance of the Public Goods hypothesis, just like classical mechanics and euclidean geometry are seen as regionalized

  4. The public goods hypothesis for the evolution of life on Earth

    Directory of Open Access Journals (Sweden)

    Bapteste Eric

    2011-08-01

    Full Text Available Abstract It is becoming increasingly difficult to reconcile the observed extent of horizontal gene transfers with the central metaphor of a great tree uniting all evolving entities on the planet. In this manuscript we describe the Public Goods Hypothesis and show that it is appropriate in order to describe biological evolution on the planet. According to this hypothesis, nucleotide sequences (genes, promoters, exons, etc. are simply seen as goods, passed from organism to organism through both vertical and horizontal transfer. Public goods sequences are defined by having the properties of being largely non-excludable (no organism can be effectively prevented from accessing these sequences and non-rival (while such a sequence is being used by one organism it is also available for use by another organism. The universal nature of genetic systems ensures that such non-excludable sequences exist and non-excludability explains why we see a myriad of genes in different combinations in sequenced genomes. There are three features of the public goods hypothesis. Firstly, segments of DNA are seen as public goods, available for all organisms to integrate into their genomes. Secondly, we expect the evolution of mechanisms for DNA sharing and of defense mechanisms against DNA intrusion in genomes. Thirdly, we expect that we do not see a global tree-like pattern. Instead, we expect local tree-like patterns to emerge from the combination of a commonage of genes and vertical inheritance of genomes by cell division. Indeed, while genes are theoretically public goods, in reality, some genes are excludable, particularly, though not only, when they have variant genetic codes or behave as coalition or club goods, available for all organisms of a coalition to integrate into their genomes, and non-rival within the club. We view the Tree of Life hypothesis as a regionalized instance of the Public Goods hypothesis, just like classical mechanics and euclidean geometry are

  5. The public goods hypothesis for the evolution of life on Earth

    LENUS (Irish Health Repository)

    McInerney, James O

    2011-08-23

    Abstract It is becoming increasingly difficult to reconcile the observed extent of horizontal gene transfers with the central metaphor of a great tree uniting all evolving entities on the planet. In this manuscript we describe the Public Goods Hypothesis and show that it is appropriate in order to describe biological evolution on the planet. According to this hypothesis, nucleotide sequences (genes, promoters, exons, etc.) are simply seen as goods, passed from organism to organism through both vertical and horizontal transfer. Public goods sequences are defined by having the properties of being largely non-excludable (no organism can be effectively prevented from accessing these sequences) and non-rival (while such a sequence is being used by one organism it is also available for use by another organism). The universal nature of genetic systems ensures that such non-excludable sequences exist and non-excludability explains why we see a myriad of genes in different combinations in sequenced genomes. There are three features of the public goods hypothesis. Firstly, segments of DNA are seen as public goods, available for all organisms to integrate into their genomes. Secondly, we expect the evolution of mechanisms for DNA sharing and of defense mechanisms against DNA intrusion in genomes. Thirdly, we expect that we do not see a global tree-like pattern. Instead, we expect local tree-like patterns to emerge from the combination of a commonage of genes and vertical inheritance of genomes by cell division. Indeed, while genes are theoretically public goods, in reality, some genes are excludable, particularly, though not only, when they have variant genetic codes or behave as coalition or club goods, available for all organisms of a coalition to integrate into their genomes, and non-rival within the club. We view the Tree of Life hypothesis as a regionalized instance of the Public Goods hypothesis, just like classical mechanics and euclidean geometry are seen as

  6. Statistical signal analysis of the Phanerozoic ð13C curve: implications for Earth system evolution

    Science.gov (United States)

    Bachan, A.; Kump, L. R.; Payne, J.; Saltzman, M.; Thomas, E.

    2014-12-01

    In recent years, vast amounts of carbon isotopic data have been collected allowing the construction of the Phanerozoic δ13C curve in unprecedented detail. Our dataset comprises 8143 points spanning the last 541 m.y., with a mean spacing of 66 k.y. The average δ13C of Phanerozoic carbonate is 1 ‰ ± 2 ‰, in accordance with the canonical values measured in the past. However, the record also shows numerous, highly resolved, large (± 6 ‰) excursions whose magnitude declines through time, especially going into the late Mesozoic and Cenozoic. When the magnitude - distribution of the excursions is tabulated we find that it follows a power law: plotting the min-max differences vs. number of bins in which a particular value occurs reveals that the data fall on a semilogarithmic line with a slope of -0.23 and R2 = 0.99. The result is insensitive to outliers: smoothing the data with lowess, spline, Savitzky-Golay, and Butterworth filters yields similar results. The continuity from small variation to large perturbations, both positive and negative, suggests that, despite the numerous proposed causes for individual carbon isotopic evens, there is likely an underlying mechanism which governs the magnitude of δ13C response to perturbations. We suggest that a mechanism acting to amplify carbon cycle perturbations is the key to explaining the power-law distribution, and identify the anoxia-productivity feedback as the most likely candidate. Establishment of sulfidic conditions is accompanied by increased release of phosphate to the water column, which allows for further productivity, and thus acts as a destabilizing, positive, feedback. This feedback would act to increase carbon cycle swings irrespective of their proximal trigger. The decline in frequency of anoxic-sulfidic bottom waters in the world's oceans, and potential disappearance in the Late Mesozoic-Cenozoic, may account for a reduction in the Earth system's gain and increase in its resilience.

  7. Dynamical systems for modeling the evolution of the magnetic field of stars and Earth

    Science.gov (United States)

    Popova, H.

    2016-02-01

    The cycles of solar magnetic activity are connected with a solar dynamo that operates in the convective zone. Solar dynamo mechanism is based on the combined action of the differential rotation and the alpha-effect. Application of these concepts allows us to get an oscillating solution as a wave of the toroidal field propagating from middle latitudes to the equator. We investigated the dynamo model with the meridional circulation by the low-mode approach. This approach is based on an assumption that the solar magnetic field can be described by non-linear dynamical systems with a relatively small number of parameters. Such non-linear dynamical systems are based on the equations of dynamo models. With this method dynamical systems have been built for media which contains the meridional flow and thickness of the convection zone of the star. It was shown the possibility of coexistence of quiasi-biennial and 22-year cycle. We obtained the different regimes (oscillations, vacillations, dynamo-bursts) depending on the value of the dynamo-number, the meridional circulation, and thickness of the convection zone. We discuss the features of these regimes and compare them with the observed features of evolution of the solar and geo magnetic fields. We built theoretical paleomagnetic time scale and butterfly-diagrams for the helicity and toroidal magnetic field for different regimes.

  8. Ediacaran paleomagnetic field records from Laurentia: Insights into the evolution of the diversity of life and Earth's deep interior

    Science.gov (United States)

    Bono, R. K.; Tarduno, J. A.

    2015-12-01

    The Ediacaran to early Cambrian interval (~635-530 Ma) marks a tremendous increase in biotic diversity known as the Cambrian explosion. The magnitude of the biotic evolution has motivated hypotheses evoking a role for abiotic/environmental causal factors. For example, a rotation of the entire solid Earth by 90°, in what has been called an inertial interchange true polar wander (IITPW) event, has been linked to these events. One of the primary data sets motivating IITPW has been the report of nearly orthogonal directions from the Sept-Îles (ca. 565 Ma) intrusion (Quebec, Canada) on the basis of whole rock paleomagnetic analyses. We have found that only one direction (shallow) from our sampling of the Sept-Îles intrusion is carried by single domain magnetic grains and thus can be considered primary (Bono and Tarduno, Geology, 2015). Moreover, we find that the geomagnetic field was reversing during cooling of the intrusion; the small spatial scales on which we see antipodal directions suggest a very rapid reversal rate. Preliminary total-TRM paleointensity results from the Sept-Îles intrusion suggest a low field strength. The high geomagnetic reversal rate and low geomagnetic field intensity that characterize a portion of the Jurassic (ca. 165 Ma) may be an analog for field behavior during the Ediacaran to early Cambrian. This model may provide insight into the development of Earth's interior; if high thermal core conductivity values are correct, the onset of inner core growth is predicted to have an age similar to that of our directional and paleointensity data. To test these linkages, we investigate dated localities of the Grenville dikes (ca. 590 Ma) from which classic paleomagnetic results on whole rocks (Murthy, 1971) have long figured into debates over the paleolatitude history of Laurentia. New rock- and paleo-magnetic experiments testing single crystal feldspars from Laurentian Ediacaran intrusive units will be discussed, along with new estimates of

  9. Evolution of the Proterozoic Earth System: Insights from the ∆17O Record of Sedimentary Sulfate Minerals

    Science.gov (United States)

    Crockford, P. W.; Hayles, J. A.; Halverson, G. P.; Bekker, A.; Rainbird, R.; Wing, B. A.

    2014-12-01

    Triple oxygen isotope ratios (18O/16O and 17O/16O) are a powerful tool to tease out interconnections within the Surface Earth System, both today and throughout Earth's history. This ability comes from the fact that stratospheric photochemistry imparts a negative ∆17O anomaly (∆17O = δ17O - 0.52×δ18O) to atmospheric oxygen whose magnitude is proportional to pCO2 levels and photosynthetic oxygen production. Atmospheric oxygen readily weathers continental sulfides and, as a result, the secular variations in atmospheric ∆17O values may be recorded in marine sulfate minerals (barite, gypsum and anhydrite). The largest ∆17O anomalies found in the rock record are from peculiar barite layers that immediately post-date the 635 Ma Marinoan Snowball Event. While these anomalies have been interpreted to result from a weak post-glacial photosynthetic O2 flux, the balance of other evidence (e.g., Zn isotope records of near-modern post-glacial productivity) suggests that they instead reflect the elevated CO2 levels thought to be required to exit a snowball state. As this situation illustrates, the ∆17O record by itself does not provide a unique solution between production of the anomaly by stratospheric reactions and its destruction by global biospheric productivity. In the context of additional geological and geochemical constraints, however, a marine sulfate ∆17O record has the potential to provide new insights into paleoatmospheres, paleoclimates, and paleoproductivity. We have produced new data (n ≈ 200) for Proterozoic evaporites that extend the sulfate ∆17O record from the Neoproterozoic to ~2.3 Ga. This data will be interpreted within our current understanding of Proterozoic Earth System Evolution on basinal to global scales and will address key questions that include: Were Paleoproterozoic glacial episodes terminated by elevated pCO2? Was the Great Oxidation Event accompanied by enhanced productivity? Does the lack of C isotope variability throughout

  10. Mechanisms of inclusion evolution and intra-granular acicular ferrite formation in steels containing rare earth elements

    Institute of Scientific and Technical Information of China (English)

    Xiaoxuan DENG; Min JIANG; Xinhua WANG

    2012-01-01

    Inclusion characteristic and microstructure of rare earth (RE) elements containing steel were evaluated with scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS),element-mapping,optical microscopy (OM),and automated feature analysis (AFA) option equipped with ASPEX PSEM.Factsage was used tocalculate the equilibrium inclusion composition.Based on the calculation,an inclusion evolution mechanism was proposed.Furthermore,line scanning analysis was used to elucidate the intra-granular acicular ferrite (IAF) nucleation mechanism.The result showed that two different inclusions exist in sample steel:(Mn-Al-Si-Ti-La-Ce-O)+MnS complex inclusion and isolated MnS inclusion.Almost all nucleation sites for IAF are complex inclusions,while single MnS inclusion cannot induce IAF.A possible formation mechanism of complex inclusion is proposed based on calculated results using Factsage,which agrees well with experimental results.A Mn-depletion zone (MDZ) which exists adjacent to the (Mn-A1-Si-Ti-La-Ce-O) +-MnS complex inclusion can account for the IAF formation.However,the low volume fraction (1.49× 10-7)of effective inclusion may result in onlv 10% (volume fraction) IAF.

  11. Time variability in Cenozoic reconstructions of mantle heat flow: plate tectonic cycles and implications for Earth's thermal evolution.

    Science.gov (United States)

    Loyd, S J; Becker, T W; Conrad, C P; Lithgow-Bertelloni, C; Corsetti, F A

    2007-09-04

    The thermal evolution of Earth is governed by the rate of secular cooling and the amount of radiogenic heating. If mantle heat sources are known, surface heat flow at different times may be used to deduce the efficiency of convective cooling and ultimately the temporal character of plate tectonics. We estimate global heat flow from 65 Ma to the present using seafloor age reconstructions and a modified half-space cooling model, and we find that heat flow has decreased by approximately 0.15% every million years during the Cenozoic. By examining geometric trends in plate reconstructions since 120 Ma, we show that the reduction in heat flow is due to a decrease in the area of ridge-proximal oceanic crust. Even accounting for uncertainties in plate reconstructions, the rate of heat flow decrease is an order of magnitude faster than estimates based on smooth, parameterized cooling models. This implies that heat flow experiences short-term fluctuations associated with plate tectonic cyclicity. Continental separation does not appear to directly control convective wavelengths, but rather indirectly affects how oceanic plate systems adjust to accommodate global heat transport. Given that today's heat flow may be unusually low, secular cooling rates estimated from present-day values will tend to underestimate the average cooling rate. Thus, a mechanism that causes less efficient tectonic heat transport at higher temperatures may be required to prevent an unreasonably hot mantle in the recent past.

  12. Evolution of nutritional therapy prescription in critically ill patients Evolución de la prescripción de la terapia nutricional en pacientes críticamente enfermos

    Directory of Open Access Journals (Sweden)

    D. Borges Dock-Nascimento

    2005-10-01

    Full Text Available Aim: The aim of this study was to investigate factors that may affect the evolution of the caloric prescription in critically ill patients. Local: Intensive care unit patients. Patients: 60 patients (33 M and 27 F; median age = 49 (15-93 y were followed prospectively. They were divided in three groups according to the diagnostic: a trauma (n = 20; b surgical (n = 22, and 3 medical treatment (n = 18. Forty-and-one (68.3% patients received enteral nutrition (EN, 17 (28.3% parenteral nutrition (TPN, and 2 (3.4% TNP and EN. Nutritional status was graded B or C by global subjective evaluation. Methods: Endpoints of the study were the time to begin the nutritional support, success or failure of the caloric prescription, and the evolution of the planned caloric prescription. The caloric evolution was considered as success if the prescription for the patient attained: a 25% of the caloric requirements on the 1st day; b 50% until the 3rd day; c 75% until the 6th day; and e 100% until the 10th day of the beginning of the support. Results: In 54 (90% patients, the nutritional support has begun until 48h after admission and in 73.3% (44 patients, until the first 24 hours. EN was most prescribed for both trauma and medical patients while NPT was most used for surgical patients (p Objetivo: El objetivo de este estudio fue investigar los factores que pueden afectar la evolución de la prescripción calórica en pacientes críticamente enfermos. Ambito: Pacientes de la unidad de cuidados intensivos. Pacientes: 60 pacientes (33 M y 27 F; con edad mediana = 49 (15-93 años fueram seguidos prospectivamente. Fueron divididos en tres grupos según el diagnóstico: a trauma (n = 20; b quirúrgico (n = 22, y 3 tratamiento clínico (n = 18. Cuarenta-y-uno (68,3% pacientes recibieron la nutrición enteral (EN, 17 (28,3%, la nutrición parenteral (TPN y 2 (3,4% TNP y EN. El estado nutritional era B o C calificado por la evaluación subjetiva global. Métodos: Las

  13. On the chronology of lunar origin and evolution. Implications for Earth, Mars and the Solar System as a whole

    Science.gov (United States)

    Geiss, Johannes; Rossi, Angelo Pio

    2013-11-01

    An origin of the Moon by a Giant Impact is presently the most widely accepted theory of lunar origin. It is consistent with the major lunar observations: its exceptionally large size relative to the host planet, the high angular momentum of the Earth-Moon system, the extreme depletion of volatile elements, and the delayed accretion, quickly followed by the formation of a global crust and mantle. According to this theory, an impact on Earth of a Mars-sized body set the initial conditions for the formation and evolution of the Moon. The impact produced a protolunar cloud. Fast accretion of the Moon from the dense cloud ensured an effective transformation of gravitational energy into heat and widespread melting. A "Magma Ocean" of global dimensions formed, and upon cooling, an anorthositic crust and a mafic mantle were created by gravitational separation. Several 100 million years after lunar accretion, long-lived isotopes of K, U and Th had produced enough additional heat for inducing partial melting in the mantle; lava extruded into large basins and solidified as titanium-rich mare basalt. This delayed era of extrusive rock formation began about 3.9 Ga ago and may have lasted nearly 3 Ga. A relative crater count timescale was established and calibrated by radiometric dating (i.e., dating by use of radioactive decay) of rocks returned from six Apollo landing regions and three Luna landing spots. Fairly well calibrated are the periods ≈4 Ga to ≈3 Ga BP (before present) and ≈0.8 Ga BP to the present. Crater counting and orbital chemistry (derived from remote sensing in spectral domains ranging from γ- and x-rays to the infrared) have identified mare basalt surfaces in the Oceanus Procellarum that appear to be nearly as young as 1 Ga. Samples returned from this area are needed for narrowing the gap of 2 Ga in the calibrated timescale. The lunar timescale is not only used for reconstructing lunar evolution, but it serves also as a standard for chronologies of the

  14. Prescription Drug Overdose

    Centers for Disease Control (CDC) Podcasts

    2013-07-02

    In this podcast, Dr. Tom Frieden, CDC Director, discusses the epidemic of prescription drug overdose, especially in women, and what can be done about it.  Created: 7/2/2013 by National Center for Injury Prevention and Control.   Date Released: 3/6/2014.

  15. A trio of horseshoes: past, present and future dynamical evolution of Earth co-orbital asteroids 2015 XX169, 2015 YA and 2015 YQ1

    CERN Document Server

    Marcos, C de la Fuente

    2016-01-01

    It is widely accepted that a quasi-steady-state flux of minor bodies moving in and out of the co-orbital state with the Earth may exist. Some of these objects are very good candidates for future in situ study due to their favourable dynamical properties. In this paper, we show that the recently discovered near-Earth asteroids 2015 XX169, 2015 YA and 2015 YQ1 are small transient Earth co-orbitals. These new findings increase the tally of known Earth co-orbitals to 17. The three of them currently exhibit asymmetric horseshoe behaviour subjected to a Kozai resonance and their short-term orbital evolution is rather unstable. Both 2015 YA and 2015 YQ1 may leave Earth's co-orbital zone in the near future as they experience close encounters with Venus, the Earth-Moon system and Mars. Asteroid 2015 XX169 may have remained in the vicinity of, or trapped inside, the 1:1 mean motion resonance with our planet for many thousands of years and may continue in that region for a significant amount of time into the future.

  16. Medicare Prescription Drug Benefit Manual

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Part D Prescription Drug Benefit Manual (PDBM) is user guide to Part D Prescription Drug Program. It includes information on general provisions, benefits,...

  17. Evolution of oral antibiotics requests without prescription in a community pharmacy / Evolución de la demanda de antibióticos orales sin receta en una farmacia comunitaria

    Directory of Open Access Journals (Sweden)

    Barris D

    2005-07-01

    Full Text Available Objectives: To analyze the demand of oral antibiotics without prescription in an community pharmacy, and to compare this demand with 2000. Methods: Cross-sectional descriptive study in a community pharmacy at Benalmadena – Malaga Spain. From March to September 2004, all patients requesting an antibiotic without prescription were surveyed, gathering data about: age, gender, requested antibiotic, who is the antibiotic for, who advised the antibiotic, requesting cause (health problem, and pharmacist intervention result. Results: 279 requests for oral antibiotics without prescription were recorded. Age group more frequently requesting antibiotics is 31-45 years old (41.2%. Someone different from the user did 46.6% of requests. Self-medication reached 57.0% of total antibiotics, and medical prescription without a prescription form was 43.0%. Total antibiotics request by therapeutic group was: penicillins (49.1%, macrolides (17.2%, quinolones (6.8%, cefalosporins (6.1%, sulfamides (5.4%, and tetraciclins (3.2%. The main causes for requesting were throat problems (36.2% and teeth problems (23.3%. In 55.4% of self-medication requests pharmacist could not persuade the patient to use a different drug or to visit the physician. Conclusions: In our health-care area, there exist evidence of high percentages of self-medication with antibiotics, and of prescriptions without a prescription form.

  18. Prescription in Dutch general practice.

    NARCIS (Netherlands)

    Dijk, L. van

    2006-01-01

    The second Dutch National Survey of General Practice (DNSGP-2) has combined registration data on morbidity and prescription, making it possible to unravel diagnosis-specific prescription behaviour of general practitioners(GPs). Prescription rates for different disorders vary considerably, especially

  19. Earth-abundant oxygen evolution catalysts coupled onto ZnO nanowire arrays for efficient photoelectrochemical water cleavage.

    Science.gov (United States)

    Jiang, Chaoran; Moniz, Savio J A; Khraisheh, Majeda; Tang, Junwang

    2014-09-26

    ZnO has long been considered as a model UV-driven photoanode for photoelectrochemical water splitting, but its performance has been limited by fast charge-carrier recombination, extremely poor stability in aqueous solution, and slow kinetics of water oxidation. These issues were addressed by applying a strategy of optimization and passivation of hydrothermally grown 1D ZnO nanowire arrays. The length and diameter of bare ZnO nanowires were optimized by varying the growth time and precursor concentration to achieve optimal photoelectrochemical performance. The addition of earth-abundant cobalt phosphate (Co-Pi) and nickel borate (Ni-B) oxygen evolution catalysts onto ZnO nanowires resulted in substantial cathodic shifts in onset potential to as low as about 0.3 V versus the reversible hydrogen electrode (RHE) for Ni-B/ZnO, for which a maximum photocurrent density of 1.1 mA cm(-2) at 0.9 V (vs. RHE) with applied bias photon-to-current efficiency of 0.4 % and an unprecedented near-unity incident photon-to-current efficiency at 370 nm. In addition the potential required for saturated photocurrent was dramatically reduced from 1.6 to 0.9 V versus RHE. Furthermore, the stability of these ZnO nanowires was significantly enhanced by using Ni-B compared to Co-Pi due to its superior chemical robustness, and it thus has additional functionality as a stable protecting layer on the ZnO surface. These remarkable enhancements in both photocatalytic activity and stability directly address the current severe limitations in the use of ZnO-based photoelectrodes for water-splitting applications, and can be applied to other photoanodes for efficient solar-driven fuel synthesis.

  20. Fermion field renormalization prescriptions

    OpenAIRE

    Zhou, Yong

    2005-01-01

    We discuss all possible fermion field renormalization prescriptions in conventional field renormalization meaning and mainly pay attention to the imaginary part of unstable fermion Field Renormalization Constants (FRC). We find that introducing the off-diagonal fermion FRC leads to the decay widths of physical processes $t\\to c Z$ and $b\\to s \\gamma$ gauge-parameter dependent. We also discuss the necessity of renormalizing the bare fields in conventional quantum field theory.

  1. Building Partnerships to Address Community Geoscience Priorities: A Brief History of the Thriving Earth Exchange (TEX) Model and its Evolution

    Science.gov (United States)

    Finn, C.; Udu-gama, N.; Pandya, R.; Leshin, L. A.; McEntee, C.; Williams, B. M.; Goodwin, M.

    2016-12-01

    Increasingly, communities around the world are being challenged by extremes in climatic change and natural hazards and a lack of key natural resources. In many cases, such communities do not have access to the experts and resources they need to address these changes. While partnerships are being developed to address these challenges, there is a need to bring communities and scientists together equitably. Thriving Earth Exchange (TEX), a program powered by the American Geophysical Union (AGU), seeks to connect communities by offering them scientists that can work with them on developing effective solutions for their real-life climate change, natural hazards and/or natural resources challenges. TEX advocates community science - the notion that scientists and communities equitably work together to identify how science can advance local priorities such that it produces local impact, guides future research and generates solutions that can be shared. The concept for TEX evolved from 2011 AGU Council discussions on potential options for impacting AGU's upcoming Centennial. The concept started as a single "Grand Challenge" concept, but evolved through several trails and iterations to today's vibrant TEX program and model. The TEX process is not for every community or scientist. In order to ensure that a community can proceed through a project with a scientist, TEX has found that they often must have a mandate to work on the issue at hand. For instance, if a planning department is tasked with doing a climate vulnerability assessment, a project looking at how heat extremes affect the elderly could probably proceed without interruption from other internal community processes. In some cases, available funds acts as an impetus for a community to seek action. Yet at other times, an individual's passion to address a community challenge may be the spark required to turn ideas into action. This presentation will provide an overview of the TEX genesis within AGU, and its growth and

  2. How Thermal Evolution and Mass Loss Sculpt Populations of Super-Earths and Sub-Neptunes: Application to the Kepler-11 System and Beyond

    CERN Document Server

    Lopez, Eric D; Miller, Neil K

    2012-01-01

    We use models of thermal evolution and XUV-driven mass loss to explore the composition and history of low-mass low-density transiting planets. We investigate the Kepler-11 system in detail and provide estimates of both the current and past planetary compositions. We find that a H/He atmosphere on Kepler-11b is highly vulnerable to mass loss. By comparing to formation models, we show that in situ formation of the system is unlikely. Instead we propose that it is a water-rich system of sub-Neptunes that migrated from beyond the snow line. For the broader population of observed planets, we show that there is a threshold in bulk planet density and incident flux above which no low-mass transiting planets have been observed. We suggest that this threshold is due to the instability of H/He atmospheres to XUV-driven mass loss. Importantly, we find that this flux-density threshold is well reproduced by our thermal evolution/contraction models that incorporate a standard mass loss prescription. Treating the planets' co...

  3. Kingian Co-Evolution of the Water and Mineral/Rock Components for Earth and Mars: Implications for Planetary Habitability (Invited)

    Science.gov (United States)

    Baker, V. R.

    2013-12-01

    Planetary habitability may fluctuate episodically against a background provided by the co-evolution of a planet's mineral/rock (geosphere) components and its water (hydrosphere) in relation to its position in a circumstellar system. The water/rock (geosphere/hydrosphere) co-evolution can be inferred from the geological histories of the terrestrial planets of the solar system, particularly from the very extensive understanding of Earth and Mars. Habitability and water/rock co-evolution have components that are tychistic (i.e., driven by chance) and anancastic (i.e., dynamically driven largely by deterministic forces). They also have a final, end-directed (i.e., teleomatic) aspect that operates in accordance with natural laws. This is a larger perspective on the idea of planetary habitability than is generally associated with an astronomical approach, and it incorporates additional insights from a geological perspective on the issue. The geological histories of Mars and Earth are punctuated with critical, short-term epochs of extreme change, which for Earth are known to be associated with major disruptions of its biosphere. These catastrophic epochs can be described as a type of non-Darwinian evolution that was envisioned by the geologist Clarence King. In an 1877 paper King proposed that accelerated evolutionary change occurs during sudden environmental disruptions. Such Kingian disruptions in mineral/rock and water evolution mark the planetary histories of Mars and Earth, including the early formation and condensation of a steam atmosphere, an impacting cataclysm at about 3.9 to 4 Ga, episodes of concentrated volcanism and tectonism, and associated rapid changes in the linked atmosphere and hydrosphere. These disruptions are closely tied to migrations of water between different planetary reservoirs, the nature of planetary accretion, the origin of a physically coupled atmosphere and ocean, the prospects for initiating plate tectonics, and punctuated greenhouse

  4. Prescription-induced jump distributions in multiplicative Poisson processes

    Science.gov (United States)

    Suweis, Samir; Porporato, Amilcare; Rinaldo, Andrea; Maritan, Amos

    2011-06-01

    Generalized Langevin equations (GLE) with multiplicative white Poisson noise pose the usual prescription dilemma leading to different evolution equations (master equations) for the probability distribution. Contrary to the case of multiplicative Gaussian white noise, the Stratonovich prescription does not correspond to the well-known midpoint (or any other intermediate) prescription. By introducing an inertial term in the GLE, we show that the Itô and Stratonovich prescriptions naturally arise depending on two time scales, one induced by the inertial term and the other determined by the jump event. We also show that, when the multiplicative noise is linear in the random variable, one prescription can be made equivalent to the other by a suitable transformation in the jump probability distribution. We apply these results to a recently proposed stochastic model describing the dynamics of primary soil salinization, in which the salt mass balance within the soil root zone requires the analysis of different prescriptions arising from the resulting stochastic differential equation forced by multiplicative white Poisson noise, the features of which are tailored to the characters of the daily precipitation. A method is finally suggested to infer the most appropriate prescription from the data.

  5. Evolution of the 2012 July 12 CME from the Sun to the Earth: Data-Constrained Three-Dimensional MHD Simulations

    CERN Document Server

    Shen, Fang; Zhang, Jie; Hess, Phillip; Wang, Yuming; Feng, Xueshang; Cheng, Hongze; Yang, Yi

    2015-01-01

    The dynamic process of coronal mass ejections (CMEs) in the heliosphere provides us the key information for evaluating CMEs' geo-effectiveness and improving the accurate prediction of CME induced Shock Arrival Time (SAT) at the Earth. We present a data constrained three dimensional (3D) magnetohydrodynamic (MHD) simulation of the evolution of the CME in a realistic ambient solar wind for the July 12-16, 2012 event by using the 3D COIN-TVD MHD code. A detailed comparison of the kinematic evolution of the CME between the observations and the simulation is carried out, including the usage of the time-elongation maps from the perspectives of both Stereo A and Stereo B. In this case study, we find that our 3D COIN-TVD MHD model, with the magnetized plasma blob as the driver, is able to re-produce relatively well the real 3D nature of the CME in morphology and their evolution from the Sun to Earth. The simulation also provides a relatively satisfactory comparison with the in-situ plasma data from the Wind spacecraf...

  6. From description to prescription

    DEFF Research Database (Denmark)

    McQuaid, Sara Dybris

    From Description to Prescription: Politics of Recognition, Consociational Theory and the Conflict in Northern Ireland. Within academic discourses on Northern Ireland the politics of recognition and particularly the theory of consociational democracy has made a profound impact. First introduced...... politico-cultural antagonisms in Northern Ireland. However, the terms ‘consociationalism’ or ‘consociational democracy’ are wholly absent from political discourses: they are never used in any of the governmental and constitutional documents between 1969 and 2006. As such, juxtaposing academic literature...... to integration, eventually converged in authoritative academic and political discourses....

  7. Stereoscopic study of the kinematic evolution of a coronal mass ejection and its driven shock from the sun to the earth and the prediction of their arrival times

    Energy Technology Data Exchange (ETDEWEB)

    Hess, Phillip; Zhang, Jie, E-mail: phess4@gmu.edu [School of Physics, Astronomy and Computational Sciences, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)

    2014-09-01

    We present a detailed study of the complete evolution of a coronal mass ejection (CME). We have tracked the evolution of both the ejecta and its shock, and further fit the evolution of the fronts to a simple but physics-based analytical model. This study focuses on the CME initiated on the Sun on 2012 July 12 and arriving at the Earth on 2012 July 14. Shock and ejecta fronts were observed by white light images, as well as in situ by the Advanced Composition Explorer satellite. We find that the propagation of the two fronts is not completely dependent upon one another, but can each be modeled in the heliosphere with a drag model that assumes the dominant force of affecting CME evolution to be the aerodynamic drag force of the ambient solar wind. Results indicate that the CME ejecta front undergoes a more rapid deceleration than the shock front within 50 R {sub ☉} and therefore the propagation of the two fronts is not completely coupled in the heliosphere. Using the graduated cylindrical shell model, as well as data from time-elongation stack plots and in situ signatures, we show that the drag model can accurately describe the behavior of each front, but is more effective with the ejecta. We also show that without the in situ data, based on measurements out to 80 R {sub ☉} combined with the general values for drag model parameters, the arrival of both the shock and ejecta can be predicted within four hours of arrival.

  8. A prescription fraud detection model.

    Science.gov (United States)

    Aral, Karca Duru; Güvenir, Halil Altay; Sabuncuoğlu, Ihsan; Akar, Ahmet Ruchan

    2012-04-01

    Prescription fraud is a main problem that causes substantial monetary loss in health care systems. We aimed to develop a model for detecting cases of prescription fraud and test it on real world data from a large multi-center medical prescription database. Conventionally, prescription fraud detection is conducted on random samples by human experts. However, the samples might be misleading and manual detection is costly. We propose a novel distance based on data-mining approach for assessing the fraudulent risk of prescriptions regarding cross-features. Final tests have been conducted on adult cardiac surgery database. The results obtained from experiments reveal that the proposed model works considerably well with a true positive rate of 77.4% and a false positive rate of 6% for the fraudulent medical prescriptions. The proposed model has the potential advantages including on-line risk prediction for prescription fraud, off-line analysis of high-risk prescriptions by human experts, and self-learning ability by regular updates of the integrative data sets. We conclude that incorporating such a system in health authorities, social security agencies and insurance companies would improve efficiency of internal review to ensure compliance with the law, and radically decrease human-expert auditing costs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  9. From description to prescription

    DEFF Research Database (Denmark)

    McQuaid, Sara Dybris

    current prominent position within the academy. Structuring these interpretations alongside evolving constitutional policy, the paper will argue that although consociationalism has developed as an indeterminate research design, the inherent logic of managing diversity on the basis of equality as opposed......From Description to Prescription: Politics of Recognition, Consociational Theory and the Conflict in Northern Ireland. Within academic discourses on Northern Ireland the politics of recognition and particularly the theory of consociational democracy has made a profound impact. First introduced...... by the Dutch political scientist Arend Lijphart in a World Politics article from 1969, it has since increased in importance, both as an authoritative explanatory framework for the institutional design inherent in political agreements and as a desirable approach to manage, balance and potentially dissolve...

  10. Evolution of the solar activity over time and effects on planetary atmospheres. II. kappa^1 Ceti, an analog of the Sun when life arose on Earth

    CERN Document Server

    Ribas, I; Ferreira, L D; Hebrard, E; Selsis, F; Catalan, S; Garces, A; Nascimento, J D do; de Medeiros, J R

    2010-01-01

    The early evolution of Earth's atmosphere and the origin of life took place at a time when physical conditions at the Earth where radically different from its present state. The radiative input from the Sun was much enhanced in the high-energy spectral domain, and in order to model early planetary atmospheres in detail, a knowledge of the solar radiative input is needed. We present an investigation of the atmospheric parameters, state of evolution and high-energy fluxes of the nearby star kap^1 Cet, previously thought to have properties resembling those of the early Sun. Atmospheric parameters were derived from the excitation/ionization equilibrium of Fe I and Fe II, profile fitting of Halpha and the spectral energy distribution. The UV irradiance was derived from FUSE and HST data, and the absolute chromospheric flux from the Halpha line core. From careful spectral analysis and the comparison of different methods we propose for kap^1 Cet the following atmospheric parameters: Teff = 5665+/-30 K (Halpha profil...

  11. Advancements in medium and high resolution Earth observation for land-surface imaging: Evolutions, future trends and contributions to sustainable development

    Science.gov (United States)

    Ouma, Yashon O.

    2016-01-01

    Technologies for imaging the surface of the Earth, through satellite based Earth observations (EO) have enormously evolved over the past 50 years. The trends are likely to evolve further as the user community increases and their awareness and demands for EO data also increases. In this review paper, a development trend on EO imaging systems is presented with the objective of deriving the evolving patterns for the EO user community. From the review and analysis of medium-to-high resolution EO-based land-surface sensor missions, it is observed that there is a predictive pattern in the EO evolution trends such that every 10-15 years, more sophisticated EO imaging systems with application specific capabilities are seen to emerge. Such new systems, as determined in this review, are likely to comprise of agile and small payload-mass EO land surface imaging satellites with the ability for high velocity data transmission and huge volumes of spatial, spectral, temporal and radiometric resolution data. This availability of data will magnify the phenomenon of "Big Data" in Earth observation. Because of the "Big Data" issue, new computing and processing platforms such as telegeoprocessing and grid-computing are expected to be incorporated in EO data processing and distribution networks. In general, it is observed that the demand for EO is growing exponentially as the application and cost-benefits are being recognized in support of resource management.

  12. The sustainability of habitability on terrestrial planets: Insights, questions, and needed measurements from Mars for understanding the evolution of Earth-like worlds

    Science.gov (United States)

    Ehlmann, B. L.; Anderson, F. S.; Andrews-Hanna, J.; Catling, D. C.; Christensen, P. R.; Cohen, B. A.; Dressing, C. D.; Edwards, C. S.; Elkins-Tanton, L. T.; Farley, K. A.; Fassett, C. I.; Fischer, W. W.; Fraeman, A. A.; Golombek, M. P.; Hamilton, V. E.; Hayes, A. G.; Herd, C. D. K.; Horgan, B.; Hu, R.; Jakosky, B. M.; Johnson, J. R.; Kasting, J. F.; Kerber, L.; Kinch, K. M.; Kite, E. S.; Knutson, H. A.; Lunine, J. I.; Mahaffy, P. R.; Mangold, N.; McCubbin, F. M.; Mustard, J. F.; Niles, P. B.; Quantin-Nataf, C.; Rice, M. S.; Stack, K. M.; Stevenson, D. J.; Stewart, S. T.; Toplis, M. J.; Usui, T.; Weiss, B. P.; Werner, S. C.; Wordsworth, R. D.; Wray, J. J.; Yingst, R. A.; Yung, Y. L.; Zahnle, K. J.

    2016-10-01

    What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar system's longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to

  13. The Sustainability of Habitability on Terrestrial Planets: Insights, Questions, and Needed Measurements from Mars for Understanding the Evolution of Earth-Like Worlds

    Science.gov (United States)

    Ehlmann, B. L.; Anderson, F. S.; Andrews-Hanna, J.; Catling, D. C.; Christensen, P. R.; Cohen, B. A.; Dressing, C. D.; Edwards, C. S.; Elkins-Tanton, L. T.; Farley, K. A.; hide

    2016-01-01

    What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar systems longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to

  14. Accretion and Evolution of ~2.5 Earth-mass Planets with Voluminous H/He Envelopes

    CERN Document Server

    Bodenheimer, Peter

    2014-01-01

    Formation of planets in the Neptune size range with low-mass, but voluminous, H_2/He gaseous envelopes is modeled by detailed numerical simulations according to the core-nucleated accretion scenario. Formation locations ranging from 0.5 to 4 AU from a star of 1 solar mass are considered. The final planets have heavy-element cores of 2.2--2.5 Earth masses and envelopes in the range 0.037--0.16 Earth masses. After the formation process, which lasts 2 Myr or less, the planets evolve at constant mass up to an age of several Gyr. For assumed equilibrium temperatures of 250, 500, and 1000 K, their calculated final radii are compared with those observed by the Kepler spacecraft. For the particular case of Kepler-11 f, we address the question whether it could have formed in situ or whether migration from a formation location farther out in the disk is required.

  15. The Danish National Prescription Registry

    DEFF Research Database (Denmark)

    Kildemoes, Helle Wallach; Sørensen, Henrik Toft; Hallas, Jesper

    2011-01-01

    Introduction: Individual-level data on all prescription drugs sold in Danish community pharmacies has since 1994 been recorded in the Register of Medicinal Products Statistics of the Danish Medicines Agency. Content: The register subset, termed the Danish National Prescription Registry (DNPR......), contains information on dispensed prescriptions, including variables at the level of the drug user, the prescriber, and the pharmacy. Validity and coverage: Reimbursement-driven record keeping, with automated bar-code-based data entry provides data of high quality, including detailed information...

  16. Prescription Drugs and Cold Medicines

    Science.gov (United States)

    ... on past-month use for illicit drugs (including marijuana and prescription drugs), alcohol, and tobacco. ... neonatal abstinence syndrome, and provides evidence-based treatment options that have been shown to be safe ...

  17. Identifying Meteor Streams Containing 10-m Bolides in Near-Earth Space and Determining their Temporal Evolution

    Science.gov (United States)

    Lai, H.; Russell, C. T.; Wei, H.; Delzanno, G.; Connors, M. G.

    2013-12-01

    The collision rate of small bodies orbiting the Sun increases with decreasing size. While small bodies in the 10-m class are difficult to detect from Earth, they are relatively easily detected by interplanetary spacecraft with magnetometers. A 10m body need be struck by a body only 20 cm across (traveling at 20 km/s) to be completely disrupted. The solar wind will sweep up the charged nano-scale dust as it flows through the debris forming a magnetic cloud. Because of the large size of the magnetic cloud only a small drop in the solar wind speed is needed to provide the momentum flux required to accelerate the cloud radially from the Sun. The cloud is carried outward and can be detected by any one of several interplanetary spacecraft. This procedure was first utilized on debris co-orbiting with the comet 2201 Oljato as monitored beginning in 1978 by the Pioneer Venus Orbiter and followed up by Venus Express that is still in operation. The meteoroid trail dissipated in just 30 years. We have used ACE, Wind and STEREO to identify a meteor stream co-orbiting with asteroid 138175 whose descending node is aligned with the Sun and the Earth on about April 17 each year. We have followed this trail from 1998 to the present and find that material extends to over 30° in front of the asteroid. It has been a steady producer of collisions over the last 15 years. The period of very close approach of this material to Earth may be over for a while but the material should be accessible by robotic or crewed missions as the orbit of 139175 has only a modest eccentricity and inclination to the ecliptic plane. Matching orbits with it should be similar in difficulty to a Venus flyby mission.

  18. The Danish National Prescription Registry

    DEFF Research Database (Denmark)

    Kildemoes, Helle Wallach; Toft Sørensen, Henrik; Hallas, Jesper

    2011-01-01

    Introduction: Individual-level data on all prescription drugs sold in Danish community pharmacies has since 1994 been recorded in the Register of Medicinal Products Statistics of the Danish Medicines Agency. Content: The register subset, termed the Danish National Prescription Registry (DNPR...... on the dispensed drug. Conclusion: The possibility of linkage with many other nationwide individual-level data sources renders the DNPR a very powerful pharmacoepidemiological tool...

  19. Evolution of calculations of the virtual dipole moment of the Earth for reconstructing the oceanic inversion magnetic layer's parameters

    Science.gov (United States)

    Schreider, A. A.; Ignatova, A. A.; Schreider, Al. A.; Sajneva, A. E.; Varga, P.; Denis, C.

    2016-05-01

    The VDM (virtual dipole moment) is one of the most significant characteristics describing the behavior of the time evolution of the terrestrial magnetic field. However, we have revealed that the formulas with which VDM calculations are performed often do not coincide with each other in various literature sources. Hence, results are obtained from these calculations that cannot be identical. Their correctness is verified by comparing the dimension and obtained results with the known value of the VDM for our time.

  20. Siderophile and chalcophile element abundances in oceanic basalts, Pb isotope evolution and growth of the earth's core

    Science.gov (United States)

    Newsom, H. E.; White, W. M.; Jochum, K. P.; Hofmann, A. W.

    1986-01-01

    The hypothesis that the mantle Pb isotope ratios reflect continued extraction of Pb into the earth's core over geologic time is evaluated by studying the depeletion of chalcophile and siderophile elements in the mantle. Oceanic basalt samples are analyzed in order to determine the Pb, Sr, and Nd isotropic compositions and the abundances of siderophile and chalcophile elements and incompatible lithophile elements. The data reveal that there is no systematic variation of siderophile or chalcophile element abundances relative to abundances of lithophile elements and the Pb/Ce ratio of the mantle is constant. It is suggested that the crust formation involves nonmagmatic and magmatic processes.

  1. Antipsychotics dosage and antiparkinsonian prescriptions

    Directory of Open Access Journals (Sweden)

    Gasquet Isabelle

    2007-09-01

    Full Text Available Abstract Background To study the link between the dosage of several antipsychotics and the prescription of antiparkinsonians in an observational study. Methods In the context of a national naturalistic prospective observational study, a database containing all the prescriptions from 100 French psychiatrists during the year 2002 was analysed. The inclusion criteria were a diagnosis of schizophrenia or schizoaffective disorder and age over 18. The mean dosage of antipsychotics with and without antiparkinsonians was compared. Since there were multiple prescriptions for a given subject, generalised mixed linear models were also used to study the link between antiparkinsonian prescription and antipsychotic dosage. Results antiparkinsonians were prescribed to 32,9% of the patients. Two groups of antipsychotics were observed relating to differences in dosage when an antiparkinsonian was co prescribed or not : a first group, where the mean dosage was higher with antiparkinsonians (risperidone, amisulpride and haloperidol and a second group (clozapine, olanzapine, in which antiparkinsonian co prescription was not related to the dosage of antipsychotics. Conclusion As a conclusion, it can be said that it is important to consider the dosage and the type of antipsychotic in the treatment of patients suffering of schizophrenia, because neurological side effects are frequent and can impair quality of life. Moreover the prescription of antiparkinsonians can lead to different side effects such anticholinergic effects.

  2. Habitability of Super-Earth Planets around Main-Sequence Stars including Red Giant Branch Evolution: Models based on the Integrated System Approach

    CERN Document Server

    Cuntz, M; Schroeder, K -P; Bounama, C; Franck, S

    2011-01-01

    In a previous study published in Astrobiology, we focused on the evolution of habitability of a 10 M_E super-Earth planet orbiting a star akin to the Sun. This study was based on a concept of planetary habitability in accordance to the integrated system approach that describes the photosynthetic biomass production taking into account a variety of climatological, biogeochemical, and geodynamical processes. In the present study, we pursue a significant augmentation of our previous work by considering stars with zero-age main sequence masses between 0.5 and 2.0 M_sun with special emphasis on models of 0.8, 0.9, 1.2 and 1.5 M_sun. Our models of habitability consider again geodynamical processes during the main-sequence stage of these stars as well as during their red giant branch evolution. Pertaining to the different types of stars, we identify so-called photosynthesis-sustaining habitable zones (pHZ) determined by the limits of biological productivity on the planetary surface. We obtain various sets of solution...

  3. Earth science: Extraordinary world

    Science.gov (United States)

    Day, James M. D.

    2016-09-01

    The isotopic compositions of objects that formed early in the evolution of the Solar System have been found to be similar to Earth's composition -- overturning notions of our planet's chemical distinctiveness. See Letters p.394 & p.399

  4. Inferring internal properties of Earth's core dynamics and their evolution from surface observations and a numerical geodynamo model

    Directory of Open Access Journals (Sweden)

    J. Aubert

    2011-10-01

    Full Text Available Over the past decades, direct three-dimensional numerical modelling has been successfully used to reproduce the main features of the geodynamo. Here we report on efforts to solve the associated inverse problem, aiming at inferring the underlying properties of the system from the sole knowledge of surface observations and the first principle dynamical equations describing the convective dynamo. To this end we rely on twin experiments. A reference model time sequence is first produced and used to generate synthetic data, restricted here to the large-scale component of the magnetic field and its rate of change at the outer boundary. Starting from a different initial condition, a second sequence is next run and attempts are made to recover the internal magnetic, velocity and buoyancy anomaly fields from the sparse surficial data. In order to reduce the vast underdetermination of this problem, we use stochastic inversion, a linear estimation method determining the most likely internal state compatible with the observations and some prior knowledge, and we also implement a sequential evolution algorithm in order to invert time-dependent surface observations. The prior is the multivariate statistics of the numerical model, which are directly computed from a large number of snapshots stored during a preliminary direct run. The statistics display strong correlation between different harmonic degrees of the surface observations and internal fields, provided they share the same harmonic order, a natural consequence of the linear coupling of the governing dynamical equations and of the leading influence of the Coriolis force. Synthetic experiments performed with a weakly nonlinear model yield an excellent quantitative retrieval of the internal structure. In contrast, the use of a strongly nonlinear (and more realistic model results in less accurate static estimations, which in turn fail to constrain the unobserved small scales in the time integration of the

  5. Distribution, evolution and the effects of rare earths Ce and Y on the mechanical properties of ZK60 alloys

    Institute of Scientific and Technical Information of China (English)

    Anru Wu; Changqing Xia; Jiewen Wang

    2006-01-01

    Eight kinds of Mg-RE alloys were prepared. The distribution, evolution, and effects of RE Ce and Y in the investigated alloys were studied by examining the mechanical properties of Mg alloys using X-ray diffraction and scan electron analysis, and by TEM observation. The results show that among the investigated alloys, ZK60-1.5%Ce and ZK60-1.0%Y possessed the optimal mechanical properties. Ce and Y were distributed on the grain boundary during casting. After extrusion and T5 (150℃/0-24 h) heattreatment, Ce and Y were distributed along the extrusion direction and they existed in compound form for both as-casting and asextrusion specimens. The mechanical properties of the investigated alloys were better than those of ZK60 because of the solid solution strengthening of RE and the dispersion strengthening of Mg-RE or Mg-Zn-RE compounds.

  6. Time scale for the formation of the earth and planets and its role in their geochemical evolution

    Science.gov (United States)

    Safronov, V. S.

    1977-01-01

    The initial mass of the solar nebula is discussed. Models of a massive nebula (two solar masses and more) encounter serious difficulties: an effective mechanism of transfer of the momentum from the central part of the nebula outward, capable of leading to formation of the sun and removal of half the mass of the nebula from the solar system has not been found. As a consequence of the instability of these models, their evolution can end with the formation, not a planetary system, but of a binary star. The possibility is demonstrated of obtaining acceptable growth rates for Uranus and Neptune by prolonging the thickening of preplanetary dust in the region of large masses. The important role of large bodies in the process of formation of the planets is noted. The impacts of such bodies, moving in heliocentric orbits, could have imparted considerable additional energy to the forming Moon, which, together with the energy given off by the joining of a small number of large protomoons, could have led to a high initial temperature of the moon.

  7. Critical Zone Observatories (CZOs): Integrating measurements and models of Earth surface processes to improve prediction of landscape structure, function and evolution

    Science.gov (United States)

    Chorover, J.; Anderson, S. P.; Bales, R. C.; Duffy, C.; Scatena, F. N.; Sparks, D. L.; White, T.

    2012-12-01

    The "Critical Zone" - that portion of Earth's land surface that extends from the outer periphery of the vegetation canopy to the lower limit of circulating groundwater - has evolved in response to climatic and tectonic forcing throughout Earth's history, but human activities have recently emerged as a major agent of change as well. With funding from NSF, a network of currently six CZOs is being developed in the U.S. to provide infrastructure, data and models that facilitate understanding the evolution, structure, and function of this zone at watershed to grain scales. Each CZO is motivated by a unique set of hypotheses proposed by a specific investigator team, but coordination of cross-site activities is also leading to integration of a common set of multi-disciplinary tools and approaches for cross-site syntheses. The resulting harmonized four-dimensional datasets are intended to facilitate community-wide exploration of process couplings among hydrology, ecology, soil science, geochemistry and geomorphology across the larger (network-scale) parameter space. Such an approach enables testing of the generalizability of findings at a given site, and also of emergent hypotheses conceived independently of an original CZO investigator team. This two-pronged method for developing a network of individual CZOs across a range of watershed systems is now yielding novel observations and models that resolve mechanisms for Critical Zone change occurring on geological to hydrologic time-scales. For example, recent advances include improved understanding of (i) how mass and energy flux as modulated by ecosystem exchange transforms bedrock to structured, soil-mantled and/or erosive landscapes; (ii) how long-term evolution of landscape structure affects event-based hydrologic and biogeochemical response at pore to catchment scales; (iii) how complementary isotopic measurements can be used to resolve pathways and time scales of water and solute transport from canopy to stream, and

  8. Evolutionary Models of Super-Earths and Mini-Neptunes Incorporating Cooling and Mass Loss

    CERN Document Server

    Howe, Alex R

    2015-01-01

    We construct models of the structural evolution of super-Earth- and mini-Neptune-type exoplanets with hydrogen-helium envelopes, incorporating radiative cooling and XUV-driven mass loss. We conduct a parameter study of these models, focusing on initial mass, radius, and envelope mass fractions, as well as orbital distance, metallicity, and the specific prescription for mass loss. From these calculations, we investigate how the observed masses and radii of exoplanets today relate to the distribution of their initial conditions. Orbital distance and initial envelope mass fraction are the most important factors determining planetary evolution, particular radius evolution. Initial mass also becomes important below a "turnoff mass," which varies with orbital distance, with mass-radius curves being approximately flat for higher masses. Initial radius is the least important parameter we study, with very little difference between the hot start and cold start limits after an age of 100 Myr. Model sets with no mass los...

  9. Thermal evolution of Earth's mantle and core: Influence of reference viscosity and concentration of radioactive elements in the mantle

    Science.gov (United States)

    Nakagawa, T.; Tackley, P. J.

    2010-12-01

    In a series of studies on the thermal evolution of Earth’s mantle and core [Nakagawa and Tackley, 2004; 2005; 2010], we have assumed a reference viscosity (at T=1600 K and P=0) of 1022 Pa.s and a concentration of radioactive elements based on the surface heat flux of the Earth’s mantle (6x10-12 W/kg). In addition, the initial mantle temperature in these studies was also based on the mantle adiabat estimated from present potential temperature (1600 K). Problems with these models are that (1) the average mantle temperature increases in the initial phase of the calculation and (2) the final (present-day) surface heat flux is a factor of two lower than expected from observational constraints (46 TW [Jaupart et al., 2007]), which means the Urey ratio is higher than the expected value (~0.3) [Jaupert et al., 2007; Korenaga, 2007]. Here we present results of a coupled model of thermo-chemical mantle convection in a 2-D spherical annulus and parameterized core heat balance, in which we vary (i) the reference viscosity down to 1020 Pa.s, giving a "surface" Rayleigh number of 109, (ii) the concentration of radioactive heat-producing elements in the mantle are tried (either a theoretical estimate [Schubert et al., 2001; 25 TW], geochemical estimate [McDonough and Sun, 1995; 20 TW] and modified geochemical estimate [Lyubetskaya and Korenaga, 2006; 16 TW]) and (iii) the initial mantle adiabat (up to 2500 K at the surface). Preliminary results indicate a preference for an initial mantle adiabat of more than 2500 K and the modified geochemical estimate of radioactive element concentration, in order to understand the current thermal state of Earth’s mantle when the reference viscosity is 1022 Pa s. Results with lower reference viscosity will be presented.

  10. Prescription Program Provides Significant Savings

    Science.gov (United States)

    Rowan, James M.

    2010-01-01

    Most school districts today are looking for ways to save money without decreasing services to its staff. Retired pharmacist Tim Sylvester, a lifelong resident of Alpena Public Schools in Alpena, Michigan, presented the district with a pharmaceuticals plan that would save the district money without raising employee co-pays for prescriptions. The…

  11. Medication safety: Filling your prescription

    Science.gov (United States)

    ... medicines. Also learn what each medicine looks like. Filling Your Prescriptions Your health plan may require you to use certain pharmacies. ... standards. The website should have clear directions for filling or ... seeing you. Make sure your health plan will cover the cost of using the ...

  12. Prescriptive Exercise for Older Adults.

    Science.gov (United States)

    Piscopo, John

    1985-01-01

    In addition to physical benefits, exercise also provides a natural way to sustain mental alertness in the aging individual by supplying oxygen to the brain. A table focuses on 10 specific health-fitness problems with suggested prescriptive exercises designed to ameliorate the condition. (MT)

  13. Therapeutic Audit Of Dermatological Prescriptions

    Directory of Open Access Journals (Sweden)

    Thawani V.R

    1995-01-01

    Full Text Available Dermatological prescribing trends in outdoor patients attending Dermatology Clinic of Govt. Medical College Hospital, Nagpur were studied. In all 190 prescriptions were audited to find number of drugs per prescription, use of generic/brand names, dosage forms, frequency, duration of treatment, dose and categorywise drug consumption. The age and sex distributions of patients and disease distribution were also studied. Polypharmacy was found to be widely prevalent. More drugs were prescribed by brand names than generic. Dosage form, frequency and duration were mentioned in most of the prescriptions; however, doses of the drugs were not, in majority. The major drugs in the prescriptions were antihistaminics followed by antimicrobials , steroids and vitamins. Not much difference was found in sexes attending the Clinic. There were more female patients of acne vulgaris, disseminated lupus erythematosus and Hansen’s disease. More males suffered from scables and tinea infections. There were 4 patients who were prescribed drugs without diagnosis. Except in some cases, the prescribing was relational.

  14. E-prescription across Europe

    DEFF Research Database (Denmark)

    Kierkegaard, Patrick

    2013-01-01

    . The study concludes that member states have varying degrees of health care policy, privacy enforcement and laws concerning data protection, telecommunication services and digital signature with regards to e-Prescription. Interoperability of different systems is only a partial solution. Security...

  15. Linking the MIF-S Record of Sedimentary Rocks to the Thermal and Biological Evolutions of the Earth

    Science.gov (United States)

    Ohmoto, H.; Watanabe, Y.; Lasaga, A. C.

    2006-05-01

    -rich sediments of Archean age, compared to younger sediments, because of the probable change in relative abundances of simple/complex amino acids through geologic time (e.g., Jordan et al., 2005); and (b) the Earth's interior was probably hotter and more intensive and extensive volcanic activity took place during the Archean, as indicated by the high abundances of Archean komatiites, granitoids, and mantle plumes. Therefore, the MIF-S record of sedimentary rocks may reflect the changes in thermal structure and types of dominant organisms through geologic time, rather than a change in the atmospheric oxygen level.

  16. Building of Virtual Imaging Earth Evolution Complex Laboratory%实景虚拟地球演化综合实验室的建设

    Institute of Scientific and Technical Information of China (English)

    韩秀梅; 赵庆英; 贺金鑫; 王玉芬

    2011-01-01

    利用Web 2.0、全景VR技术将地学标本实验室搬至网络上,以吉林大学地球演化综合实验室为教学示范区,设计并开发了基于实景的3维虚拟网络实验室,用户可以通过网络漫游,对实验室中陈列的丰富的化石与地层标本以及各类古生物薄片进行参观研究.对改善地质信息的可视性起到了巨大的促进作用,为今后的实践教学打下了良好的基础.%Specimen laboratory in geological science is removed to network by the utilization of Web 2.0, panoramic VR technology.Earth evolution laboratory in Jilin university is used as demonstration plot of teaching,3D virtual network laboratory is designed and developed based on actual location, users can browse abundant fossils bed samples and various sorts of paleontological slices by net surfing, which performs enormous promotion in improving the visibility of geology information and establishes strong building for afterward teaching.

  17. 21 CFR 1306.08 - Electronic prescriptions.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Electronic prescriptions. 1306.08 Section 1306.08 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE PRESCRIPTIONS General Information... part 1311 of this chapter. (b) A pharmacy may fill an electronically transmitted prescription for a...

  18. Prescription Drug Abuse and Youth. Information Brief.

    Science.gov (United States)

    Department of Justice, Washington, DC. National Drug Intelligence Center.

    Prescription drugs, a category of psychotherapeutics that comprises prescription-type pain relievers, tranquilizers, stimulants, and sedatives, are among the substances most commonly abused by young people in the United States. Prescription drugs are readily available and can easily be obtained by teenagers who abuse these drugs to experience a…

  19. Viscosity prescription for gravitationally unstable accretion disks

    CERN Document Server

    Rafikov, Roman R

    2015-01-01

    Gravitationally unstable accretion disks emerge in a variety of astrophysical contexts - giant planet formation, FU Orioni outbursts, feeding of AGNs, and the origin of Pop III stars. When a gravitationally unstable disk is unable to cool rapidly it settles into a quasi-stationary, fluctuating gravitoturbulent state, in which its Toomre Q remains close to a constant value Q_0~1. Here we develop an analytical formalism describing the evolution of such a disk, which is based on the assumptions of Q=Q_0 and local thermal equilibrium. Our approach works in the presence of additional sources of angular momentum transport (e.g. MRI), as well as external irradiation. Thermal balance dictates a unique value of the gravitoturbulent stress \\alpha_{gt} driving disk evolution, which is a function of the local surface density and angular frequency. We compare this approach with other commonly used gravitoturbulent viscosity prescriptions, which specify the explicit dependence of stress \\alpha_{gt} on Toomre Q in an ad hoc...

  20. [Exercise prescription and nutrition therapy].

    Science.gov (United States)

    Shiota, Masatoshi; Sone, Ryoko; Matsuo, Eriko; Matsubara, Shigeru; Suzuki, Masato

    2014-08-01

    In the report of World Health Organization, the leading global risks for mortality in the world are high blood pressure (12.8%), tobacco use (8.7%), high blood glucose (5.8%), physical inactivity (5.5%), and overweight and obesity (4.8%). Increased blood pressure levels cause the increased morbidity and mortality of chronic diseases, such as stroke, myocardial infarction, chronic kidney disease. Improving the high blood pressure is considered as common challenges around the world. Exercise prescription and nutrition therapy might be important non-pharmacologic therapies in the control of hypertension. Applying these therapies to the general population can help to prevent an increase in blood pressure and decrease elevated blood pressure levels for those with hypertension. Exercise prescription and nutrition therapy are discussed using the international guidelines.

  1. Prescription Painkiller Overdoses PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2013-07-02

    This 60 second public service announcement is based on the July 2013 CDC Vital Signs report. Prescription painkiller overdoses are an under-recognized and growing problem among women. This program includes things that women and health care providers can do to reduce the risk of overdose.  Created: 7/2/2013 by Centers for Disease Control and Prevention (CDC).   Date Released: 7/2/2013.

  2. Laboratory Testing for Prescription Opioids

    OpenAIRE

    Milone, Michael C.

    2012-01-01

    Opioid analgesic misuse has risen significantly over the past two decades, and these drugs now represent the most commonly abused class of prescription medications. They are a major cause of poisoning deaths in the USA exceeding heroin and cocaine. Laboratory testing plays a role in the detection of opioid misuse and the evaluation of patients with opioid intoxication. Laboratories use both immunoassay and chromatographic methods (e.g., liquid chromatography with mass spectrometry detection),...

  3. Supporting the planning for the evolution of the EOSDIS through an in-depth understanding of user requirements for NASA's world-class Earth science data system

    Science.gov (United States)

    Griffin, V. L.; Behnke, J.; Maiden, M.; Fontaine, K.

    2004-12-01

    NASA is planning for the evolution of the Earth Observation System Data and Information System (EOSDIS), a large, complex data system currently supporting over 18 operational NASA satellite missions including the flagship EOS missions: Terra, Aqua, and Aura. A critical underpinning for the evolution planning is developing thorough knowledge of the EOSDIS users and how they use the EOSDIS products in their research and or applications endeavors. This paper provides charts and tables of results from NASA studies that characterized our users, data and techniques. Using these metrics, other projects can apply NASA's 'lessons learned' to the development and operations of their data systems. In 2004, NASA undertook an intensive study of the users and usage of EOSDIS data. The study considered trends in the types and levels of EOS data products being ordered, the expanding number of users requesting products, and the "domains" of those users. The study showed that increasing numbers of users are using the validated, geophysical products produced from the radiance measurements recorded by the EOS instruments; while there remains a steady demand for the radiance products themselves. In 2003, over 2.1 million individuals contacted EOSDIS (as identified by unique email and/or URL) with just over 10% requesting a product or service. The users came from all sectors including 40% from more than 125 countries outside the U.S. University researchers and students (.edu) received over 40% of the some 29 million data and information products disseminated by EOSDIS. The trend in method of delivery for EOSDIS data has been away from receiving data on hard media (tapes, CD-ROM, etc.) to receiving the data over the network. Over 75% of the EOSDIS data products were disseminated via electronic means in 2003 contrasted with just under 30% in 2000. To plan for system-wide evolution you need to know whether the system is meeting the users' needs and expectations. Thus, in 2004 NASA

  4. Laboratory testing for prescription opioids.

    Science.gov (United States)

    Milone, Michael C

    2012-12-01

    Opioid analgesic misuse has risen significantly over the past two decades, and these drugs now represent the most commonly abused class of prescription medications. They are a major cause of poisoning deaths in the USA exceeding heroin and cocaine. Laboratory testing plays a role in the detection of opioid misuse and the evaluation of patients with opioid intoxication. Laboratories use both immunoassay and chromatographic methods (e.g., liquid chromatography with mass spectrometry detection), often in combination, to yield high detection sensitivity and drug specificity. Testing methods for opioids originated in the workplace-testing arena and focused on detection of illicit heroin use. Analysis for a wide range of opioids is now required in the context of the prescription opioid epidemic. Testing methods have also been primarily based upon urine screening; however, methods for analyzing alternative samples such as saliva, sweat, and hair are available. Application of testing to monitor prescription opioid drug therapy is an increasingly important use of drug testing, and this area of testing introduces new interpretative challenges. In particular, drug metabolism may transform one clinically available opioid into another. The sensitivity of testing methods also varies considerably across the spectrum of opioid drugs. An understanding of opioid metabolism and method sensitivity towards different opioid drugs is therefore essential to effective use of these tests. Improved testing algorithms and more research into the effective use of drug testing in the clinical setting, particularly in pain medicine and substance abuse, are needed.

  5. Tribal and Indigenous Geoscience and Earth System Science: Ensuring the Evolution and Practice of Underrepresented Scientists and Researchers in the 21ST Century and Beyond

    Science.gov (United States)

    Bolman, J.

    2014-12-01

    The time is critical for Tribal, Indigenous and Underrepresented K-12/university students and communities to accept the duty to provide representation in Earth System Sciences/Geosciences fields of study and professions. Tribal nations in the U.S have a unique legal status rooted in a complex relationship between the U.S. federal government, individual state/local governments and Tribal authorities. Although geosciences are often at the center of these relationships, especially as they pertain to the development of natural resources, tribal economics, and environmental stewardship, Tribal/Indigenous people remain severely underrepresented in advanced geoscience education. Our students and communities have responded to the invitation. To represent and most important develop and lead research initiatives. Leadership is a central focus of the invitation to participate, as Tribal people have immense responsibility for significant landscapes across North American Continent, critical natural resources and millennia of unpretentious natural evolution with the localized native geologies, species and environmental systems. INRSEP and Pacific Northwest Tribal Nations found sustaining relationships with the Geoscience Alliance, MS PHD's, Woods Hole PEP, Native American Pacific Islander Research Experience (NAPIRE) and LSAMP programs, in addition to state/federal agencies, has advanced culturally-relevant STEM research. Research foundationally grounded on traditional ecological knowledge, individual and Tribal self-determination. A key component is student research experiences within their ancestral homelands and traversing to REU's in multiple national and international Tribal/Indigenous ancestral territories. The relationships also serve an immense capacity in tracking student achievement, promoting best practices in research development and assessing outcomes. The model has significantly improved the success of students completing STEM graduate programs. The presentation

  6. Gene trees, species trees and Earth history combine to shed light on the evolution of migration in a model avian system.

    Science.gov (United States)

    Voelker, Gary; Bowie, Rauri C K; Klicka, John

    2013-06-01

    The evolution of migration in birds has fascinated biologists for centuries. In this study, we performed phylogenetic-based analyses of Catharus thrushes, a model genus in the study of avian migration, and their close relatives. For these analyses, we used both mitochondrial and nuclear genes, and the resulting phylogenies were used to trace migratory traits and biogeographic patterns. Our results provide the first robust assessment of relationships within Catharus and relatives and indicate that both mitochondrial and autosomal genes contribute to overall support of the phylogeny. Measures of phylogenetic informativeness indicated that mitochondrial genes provided more signal within Catharus than did nuclear genes, whereas nuclear loci provided more signal for relationships between Catharus and close relatives than did mitochondrial genes. Insertion and deletion events also contributed important support across the phylogeny. Across all taxa included in the study, and for Catharus, possession of long-distance migration is reconstructed as the ancestral condition, and a North American (north of Mexico) ancestral area is inferred. Within Catharus, sedentary behaviour evolved after the first speciation event in the genus and is geographically and temporally correlated with Central American distributions and the final closure of the Central American Seaway. Migratory behaviour subsequently evolved twice in Catharus and is geographically and temporally correlated with a recolonization of North America in the late Pleistocene. By temporally linking speciation events with changes in migratory condition and events in Earth history, we are able to show support for several competing hypotheses relating to the geographic origin of migration. © 2013 John Wiley & Sons Ltd.

  7. Mega-Impacts on Mars: Implications for the Late Heavy Bombardment in the Inner Solar System, and the Early Evolution of the Earth and Mars

    Science.gov (United States)

    Frey, Herbert

    2012-01-01

    There are about 30 very large impact basins on Mars, > 1000 km in diameter, most of which are revealed by their topographic and/or crustal thickness signatures. Crater retention ages and model absolute ages suggest these all formed in a relatively short time (100-200 million years?), perhaps during a "Late Heavy Bombardment" (LHB) caused by the evolution of the orbits of the giant planets. This so-called "Nice Model" of planetary formation may explain the LHB on the Moon at about 3.9 billion years ago and would have produced a similar bombardment throughout the inner solar system. The formation of 30 very large impact basins would have had catastrophic environmental consequences for Mars, which were further complicated by the demise of the global magnetic field at about the same time. If there are no very large basins on Mars older than the 30 we see and the LHB really lasted everywhere only a short time, there may have been a relatively longer time (400 million years?) during which Mars and the Earth suffered no major impact trauma and during which conditions on both worlds may have been far more habitable than during the LHB. However, if the formation of the Mars crustal dichotomy was due to an even larger giant impact that predated the very large basins, all record of this earlier and possibly more clement time on Mars may have been erased. Ages of the smaller but still very large basins can be used to approximately date the giant impact (if it occurred). Even the very large basins appear to have reset the crater retention ages of the entire crust of Mars and may have by themselves erased any record of an earlier time.

  8. Evolution of U fractionation processes through geologic time : consequences for the variation of U deposit types from Early Earth to Present

    Science.gov (United States)

    Cuney, M.

    2009-12-01

    U deposits are known at nearly all stages of the geological cycle, but are not known prior to 2.95 Ga. Also, U deposit types vary greatly from Mesoarchean to Present. Most of these changes through time can be attributed to major modifications in the geodynamic evolution of the Earth, in magmatic fractionation processes, in the composition of the Atmosphere and in the nature of life. The first U-rich granites able to crystallize uraninite, appeared at about 3.1 Ga. They correspond to the most fractionated terms of high-K calcalkaline suites, resulting from crystal fractionation of magmas possibly derived from melting of mantle wedges enriched in K, U, Th. Highly fractionated peraluminous leucogranites, able to crystallize uraninite, appeared at about 2.6 Ga. Erosion of these two granite types led to the detrital accumulation of uraninite that formed the first U deposits on Earth: the Quartz Pebble Conglomerates from 2.95 to 2.4 Ga. From 2.3 Ga onwards, uprise of oxygen level in the atmosphere led to the oxidation of U(IV) to U(VI), U transport in solution, and exuberant development of marine algae in epicontinental platform sediments. From 2.3 to 1.8 Ga large amounts of U, previously accumulated as U(IV) minerals, were dissolved and trapped preferentially in passive margin settings, in organic-rich sediments, and which led to the formation of the world’s largest Paleoproterozoic U provinces, e.g. : the Wollaston belt, Canada and the Cahill Formation, Australia. During and after the worldwide 2.1-1.75 Ga orogenic events, responsible for the formation of the Nuna supercontinent, U trapped in these formations was the source for several types of mineralization: (i) metamorphosed U-mineralized graphitic schists, calcsilicates and meta-arkoses, (ii) diagenetic-hydrothermal remobilization with the formation of the first deposits related to redox processes at 2.0 Ga (Oklo, Gabon), (iii) partial melting of U-rich metasediments forming the uraninite disseminations in

  9. Impact of a Mandatory Prescription Drug Monitoring Program on Prescription of Opioid Analgesics by Dentists

    OpenAIRE

    Linda Rasubala; Lavanya Pernapati; Ximena Velasquez; James Burk; Yan-Fang Ren

    2015-01-01

    Prescription Drug Monitoring Programs (PDMP) are statewide databases that collect data on prescription of controlled substances. New York State mandates prescribers to consult the PDMP registry before prescribing a controlled substance such as opioid analgesics. The effect of mandatory PDMP on opioid drug prescriptions by dentists is not known. This study investigates the impact of mandatory PDMP on frequency and quantity of opioid prescriptions by dentists in a dental urgent care center. Bas...

  10. Digital Direct-to-Consumer Advertising: A Perfect Storm of Rapid Evolution and Stagnant Regulation Comment on "Trouble Spots in Online Direct-to-Consumer Prescription Drug Promotion: A Content Analysis of FDA Warning Letters".

    Science.gov (United States)

    Mackey, Tim K

    2016-02-03

    The adoption and use of digital forms of direct-to-consumer advertising (also known as "eDTCA") is on the rise. At the same time, the universe of eDTCA is expanding, as technology on Internet-based platforms continues to evolve, from static websites, to social media, and nearly ubiquitous use of mobile devices. However, little is known about how this unique form of pharmaceutical marketing impacts consumer behavior, public health, and overall healthcare utilization. The study by Kim analyzing US Food and Drug Administration (FDA) notices of violations (NOVs) and warning letters regarding online promotional activities takes us in the right direction, but study results raise as many questions as it does answers. Chief among these are unanswered concerns about the unique regulatory challenges posed by the "disruptive" qualities of eDTCA, and whether regulators have sufficient resources and oversight powers to proactively address potential violations. Further, the globalization of eDTCA via borderless Internet-based technologies raises larger concerns about the potential global impact of this form of health marketing unique to only the United States and New Zealand. Collectively, these challenges make it unlikely that regulatory science will be able to keep apace with the continued rapid evolution of eDTCA unless more creative policy solutions are explored.

  11. Digital Direct-to-Consumer Advertising: A Perfect Storm of Rapid Evolution and Stagnant Regulation; Comment on “Trouble Spots in Online Direct-to-Consumer Prescription Drug Promotion: A Content Analysis of FDA Warning Letters”

    Directory of Open Access Journals (Sweden)

    Tim K. Mackey

    2016-04-01

    Full Text Available The adoption and use of digital forms of direct-to-consumer advertising (also known as “eDTCA” is on the rise. At the same time, the universe of eDTCA is expanding, as technology on Internet-based platforms continues to evolve, from static websites, to social media, and nearly ubiquitous use of mobile devices. However, little is known about how this unique form of pharmaceutical marketing impacts consumer behavior, public health, and overall healthcare utilization. The study by Kim analyzing US Food and Drug Administration (FDA notices of violations (NOVs and warning letters regarding online promotional activities takes us in the right direction, but study results raise as many questions as it does answers. Chief among these are unanswered concerns about the unique regulatory challenges posed by the “disruptive” qualities of eDTCA, and whether regulators have sufficient resources and oversight powers to proactively address potential violations. Further, the globalization of eDTCA via borderless Internet-based technologies raises larger concerns about the potential global impact of this form of health marketing unique to only the United States and New Zealand. Collectively, these challenges make it unlikely that regulatory science will be able to keep apace with the continued rapid evolution of eDTCA unless more creative policy solutions are explored.

  12. Uderstanding Snowball Earth Deglaciation

    Science.gov (United States)

    Abbot, D. S.

    2012-12-01

    Earth, a normally clement planet comfortably in its star's habitable zone, suffered global or nearly global glaciation at least twice during the Neoproterozoic era (at about 635 and 710 million years ago). Viewed in the context of planetary evolution, these pan-global glaciations (Snowball Earth events) were extremely rapid, lasting only a few million years. The dramatic effect of the Snowball Earth events on the development of the planet can be seen through their link to rises in atmospheric oxygen and evolutionary innovations. These potential catastrophes on an otherwise clement planet can be used to gain insight into planetary habitability more generally. Since Earth is not currently a Snowball, a sound deglaciation mechanism is crucial for the viability of the Snowball Earth hypothesis. The traditional deglaciation mechanism is a massive build up of CO2 due to reduced weathering during Snowball Earth events until tropical surface temperatures reach the melting point. Once initiated, such a deglaciation might happen on a timescale of only dozens of thousands of years and would thrust Earth from the coldest climate in its history to the warmest. Therefore embedded in Snowball Earth events is an even more rapid and dramatic environmental change. Early global climate model simulations raised doubt about whether Snowball Earth deglaciation could be achieved at a CO2 concentration low enough to be consistent with geochemical data, which represented a potential challenge to the Snowball Earth hypothesis. Over the past few years dust and clouds have emerged as the essential missing additional processes that would allow Snowball Earth deglaciation at a low enough CO2 concentration. I will discuss the dust and cloud mechanisms and the modeling behind these ideas. This effort is critical for the broader implications of Snowball Earth events because understanding the specific deglaciation mechanism determines whether similar processes could happen on other planets.

  13. Influence of pharmacists expertise on physicians prescription ...

    African Journals Online (AJOL)

    The influence of pharmacist factors on physician prescription decisions was identified ... Keywords: Physician prescription behaviour, Pharmacist factor, ... addition to the influence of marketing promotion .... from the drug sales, obtaining clinic rental ... also analyzed the current status of pharmacist's ..... the buyer-seller dyad.

  14. 21 CFR 801.109 - Prescription devices.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prescription devices. 801.109 Section 801.109 Food... DEVICES LABELING Exemptions From Adequate Directions for Use § 801.109 Prescription devices. A device... direct the use of such device, and hence for which “adequate directions for use” cannot be...

  15. Practical flux prescriptions for gamma-ray burst afterglows, from early to late times

    NARCIS (Netherlands)

    Leventis, K.; van Eerten, H.J.; Meliani, Z.; Wijers, R.A.M.J.

    2012-01-01

    We present analytic flux prescriptions for broad-band spectra of self-absorbed and optically thin synchrotron radiation from gamma-ray burst afterglows, based on 1D relativistic hydrodynamic simulations. By treating the evolution of critical spectrum parameters as a power-law break between the ultra

  16. 兒童地球形狀概念演化樹之跨年級調查驗證 Validating Children’s Conceptual Evolution Tree of Earth in a Cross-Grade Study

    Directory of Open Access Journals (Sweden)

    吳育倫 Yu-Lun Wu

    2013-12-01

    Full Text Available 跨年級研究有助於課程的縱向發展,但卻耗時、費力且難以效化。而藉由電腦建立學生於不同科學主題之最適概念演化樹的「支序分類之概念演化取向」卻可克服上述限制。據此,研究者採用此取向,並以概念改變研究中已被不同學者確認心智模式類型的「地球形狀」為主題,建立了地球形狀概念演化樹之最適假說。本研究則以一、三、五年級共336 位學生為研究對象,設計地球形狀概念測驗,藉此獲得學生於各認知特徵比例消長情形,以檢驗地球形狀概念演化樹之最適假說。研究結果顯示,此假說與跨年級調查結果大致相符,且藉由假說與跨年級資料之整合,本研究清楚呈現兒童地球形狀概念發展之全貌,並對支序分類之概念演化取向之可行性提供進一步的支持。 Although a cross-grade study is helpful for designing vertical curricula, such studies require substantial time and effort and present validation concerns regarding the research results. However, a cladistic approach in conceptual evolution could be used to construct a best-fit conceptual evolution tree regarding various science topics by using a computer to overcome these limitations. Therefore, we adopted this approach and used Earth as the topic to build a best-fit conceptual evolution tree of Earth. The purpose of this study is to verify a prediction of children’s conceptual evolution trees of Earth in a cross-grade study and to validate this novel approach. We adopted a diagnostic test to investigate 336 students who attended Grades one, three, and five, to obtain the percentages of various cognitive characteristics and statuses of students in different grades. The results indicated that the prediction of the best-fit conceptual evolution tree of Earth closely fit the empirical data of the cross-grade study. The results showed that children’s conceptual evolution

  17. Earth-abundant NiS co-catalyst modified metal-free mpg-C3N4/CNT nanocomposites for highly efficient visible-light photocatalytic H2 evolution.

    Science.gov (United States)

    Zhong, Yongming; Yuan, Jielin; Wen, Jiuqing; Li, Xin; Xu, Yuehua; Liu, Wei; Zhang, Shengsen; Fang, Yueping

    2015-11-01

    In the present work, the earth-abundant NiS co-catalyst modified mesoporous graphite-like C3N4 (mpg-C3N4)/CNT nanocomposites were prepared via a two-step strategy: the sol-gel method and the direct precipitation process. The mpg-C3N4/CNT/NiS composite photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis absorption spectroscopy, photoluminescence spectroscopy (PL), photoelectrochemical (PEC) and electrochemical impedance spectra (EIS) experiments. The photocatalytic H2-production activity over the composite catalysts was also evaluated by using an aqueous solution containing triethanolamine under visible light (λ≥ 420 nm). The results showed that the loading of earth-abundant NiS co-catalysts onto metal-free mpg-C3N4/CNT nanocomposites can remarkably enhance their photocatalytic H2-production activity. The optimal loading amount of NiS on metal-free mpg-C3N4/CNT nanocomposites was about 1 wt%. The as-obtained mpg-C3N4/CNT/1% NiS ternary composite photocatalyst exhibits the best H2-evolution activity with the highest rate of about 521 μmol g(-1) h(-1) under visible light (λ≥ 420 nm), which is almost 148 times that of a pure mpg-C3N4/CNT sample. The enhanced photocatalytic activity can be mainly attributed to the synergistic effect of effectively promoted separation of photo-generated electron-hole pairs and enhanced H2-evolution kinetics. The co-loading of nanocarbon materials and earth-abundant co-catalysts onto metal-free mpg-C3N4 photocatalysts offers great potential for practical applications in photocatalytic H2 evolution under visible light illumination.

  18. ORIGIN OF THE EARTH AND MOON IN EVOLUTION OF THE SOLAR SYSTEM%太阳系演化中的地球和月球起源

    Institute of Scientific and Technical Information of China (English)

    A.A.MARAKUSHEV

    2002-01-01

    宇宙中恒星的演化始于巨星的形成,后者的质量是太阳系的数百倍,寿命估计为数百万年.重元素合成于巨星的内部.它们控制了巨星爆炸过程中( 超新星)形成的气态云和盘状物的冷凝加速度.冷凝和旋转的加速导致后代恒星质量越来越小,寿命越来越长,直到形成像太阳这样的小星体,其质量为1.989×1030kg,寿命已有几十亿年.这些小恒星的形成是冷凝过程中产生的水成冰氢星子不断聚集的结果.上一代巨星的原始星盘中的物质只有一小部分参与了冰氢星子的形成.这些星体形成于致密、高速旋转的原始恒星星盘中,周围环绕着巨行星和褐矮星.由于星体达到恒星状态,它们开始影响原恒星盘,结果导致星体相互分散,同时,最近的巨星发生表面去气作用.后者可以从巨星到恒星的质量衰减得到证实 .Upsilon Andromedae、55Cancri和HD168443等天体的巨行星记载了这样的事实.太阳系中的表面去气作用主要反映在近太阳巨星的流体外壳完全消失.由于流体外壳消失,铁-硅酸盐熔融核暴露地表,形成小的类地行星.木星也经历过表面去气作用,依据是木星具有很高的平均密度(1.3g/cm3),几乎是土星密度(0.7g/cm3)的两倍.因此,类地行星的形成经历了两个阶段:原行星(其父巨星具有重的熔融核)和正常行星(在其父行星失去流体外壳之后形成).由于离心力的作用,从流体外壳分离出来的熔融体成为巨星的卫星.类地行星在失去流体外壳的同时也失去了它们的卫星(只有月球、火卫一和火卫二例外).原地球是地球的父行星,铁-硅酸盐熔融核和月球在离心力的影响下已从其流体外壳分离出来.%The stellar evolution of the Universe has started from the formation of giant stars, the masses of which are hundreds times larger than the solar mass, and their lifetime has been estimated as millions years. Heavy

  19. Expanding earth

    Energy Technology Data Exchange (ETDEWEB)

    Carey, S.W.

    1976-01-01

    Arguments in favor of an expanding earth are presented. The author believes that the theory of plate tectonics is a classic error in the history of geology. The case for the expanding earth is organized in the following way: introductory review - face of the earth, development of expanding earth concept, necessity for expansion, the subduction myth, and definitions; some principles - scale of tectonic phenomena, non-uniformitarianism, tectonic profile, paleomagnetism, asymmetry of the earth, rotation of the earth, and modes of crustal extension; regional studies - western North America, Central America, South-East Asia, and the rift oceans; tests and cause of expansion. 824 references, 197 figures, 11 tables. (RWR)

  20. Impact of a Mandatory Prescription Drug Monitoring Program on Prescription of Opioid Analgesics by Dentists.

    Directory of Open Access Journals (Sweden)

    Linda Rasubala

    Full Text Available Prescription Drug Monitoring Programs (PDMP are statewide databases that collect data on prescription of controlled substances. New York State mandates prescribers to consult the PDMP registry before prescribing a controlled substance such as opioid analgesics. The effect of mandatory PDMP on opioid drug prescriptions by dentists is not known. This study investigates the impact of mandatory PDMP on frequency and quantity of opioid prescriptions by dentists in a dental urgent care center. Based on the sample size estimate, we collected patient records of a 3-month period before and two consecutive 3-month periods after the mandatory PDMP implementation and analyzed the data on number of visits, treatment types and drug prescriptions using Chi-square tests. For patients who were prescribed pain medications, 452 (30.6%, 190 (14.1%, and 140 (9.6% received opioid analgesics in the three study periods respectively, signifying a statistically significant reduction in the number of opioid prescriptions after implementation of the mandatory PDMP (p<0.05. Total numbers of prescribed opioid pills in a 3-month period decreased from 5096 to 1120, signifying a 78% reduction in absolute quantity. Prescriptions for non-opioid analgesics acetaminophen increased during the same periods (p<0.05. We conclude that the mandatory PDMP significantly affected the prescription pattern for pain medications by dentists. Such change in prescription pattern represents a shift towards the evidence-based prescription practices for acute postoperative pain.

  1. Prescription Opioid Usage and Abuse Relationships: An Evaluation of State Prescription Drug Monitoring Program Efficacy

    Directory of Open Access Journals (Sweden)

    Richard M. Reisman

    2009-01-01

    Full Text Available Context: The dramatic rise in the use of prescription opioids to treat non-cancer pain has been paralleled by increasing prescription opioid abuse. However, detailed analyses of these trends and programs to address them are lacking.Objective: To study the association between state shipments of prescription opioids for medical use and prescription opioid abuse admissions and to assess the effects of state prescription drug monitoring programs (PDMPs on prescription opioid abuse admissions.Design and Setting: A retrospective ecological cohort study comparing state prescription opioid shipments (source: Automation of Reports and Consolidated Orders Systems database and inpatient admissions for prescription opioid abuse (source: Treatment Episode Data Set in 14 states with PDMPs (intervention group and 36 states without PDMPs (control group for the period 1997–2003.Results: From 1997 to 2003, oxycodone, morphine, and hydrocodone shipments increased by 479%, 100%, and 148% respectively. Increasing prescription oxycodone shipments were significantly associated with increasing prescription opioid admission rates (p 0.001. PDMP states had significantly lower oxycodone shipments than the control group. PDMP states had less increase in prescription opioid admissions per year (p = 0.063. A patient admitted to an inpatient drug abuse rehabilitation program in a PDMP state was less likely to be admitted for prescription opioid drug abuse (Odds ratio = 0.775, 95% Confidence Interval 0.764–0.785.Conclusions: PDMPs appear to decrease the quantity of oxycodone shipments and the prescription opioid admission rate for states with these programs. Overall, opioid shipments rose significantly in PDMP states during the study period indicating a negligible “chilling effect” on physician prescribing.

  2. Monitoring physicians' prescription patterns on electronic health record: the prescription pattern around clinical event (PACE) algorithm.

    Science.gov (United States)

    Yoon, Dukyong; Park, Inwhee; Park, Man Young; Hong, Seung Kwon; Park, Rae Woong

    2013-01-01

    Electronic health records (EHRs) have gained attention as a valuable data source for medical research, as its adoption rate continues to rise. However, no method for the monitoring of physicians' prescription patterns has been established. Since EHR maintain all prescription data as well as clinical events that occur during the care of patients, we hypothesized that a physician's prescription pattern can be monitored from EHR. In this study, we developed a novel algorithm named PACE, Prescription pattern Around Clinical Event. This algorithm analyzes distribution of the prescription of specific drugs around the time of a clinical event. In the proof of concept study, prescription changes with regard to hyperkalemia were well represented by the algorithm, and the observed patterns well correlated with the physician's knowledge on hyperkalemia (Cohen's kappa, 0.457-0.653). We expect that this algorithm can be used to monitor the guideline adherence of physicians.

  3. Evolution of the Theory of the Earth: A Contextualized Approach for Teaching the History of the Theory of Plate Tectonics to Ninth Grade Students

    Science.gov (United States)

    Dolphin, Glenn

    2009-01-01

    Current high school Earth Science curricula and textbooks organize scientific content into isolated "units" of knowledge. Within this structure, content is taught, but in the absence of the context of fundamental understandings or the process of how the science was actually done to reach the conclusions. These are two key facets of scientific…

  4. Evolution of the Theory of the Earth: A Contextualized Approach for Teaching the History of the Theory of Plate Tectonics to Ninth Grade Students

    Science.gov (United States)

    Dolphin, Glenn

    2009-01-01

    Current high school Earth Science curricula and textbooks organize scientific content into isolated "units" of knowledge. Within this structure, content is taught, but in the absence of the context of fundamental understandings or the process of how the science was actually done to reach the conclusions. These are two key facets of scientific…

  5. Galactic Chemical Evolution

    CERN Document Server

    Mollá, M; da Costa, R; Gibson, B K; Díaz, A I

    2016-01-01

    We analyze the evolution of oxygen abundance radial gradients resulting from our chemical evolution models calculated with different prescriptions for the star formation rate (SFR) and for the gas infall rate, in order to assess their respective roles in shaping gradients. We also compare with cosmological simulations and confront all with recent observational datasets, in particular with abundances inferred from planetary nebulae. We demonstrate the critical importance in isolating the specific radial range over which a gradient is measured, in order for their temporal evolution to be useful indicators of disk growth with redshift.

  6. Medicare Prescription Drug Coverage - General Information

    Data.gov (United States)

    U.S. Department of Health & Human Services — The MMA legislation provides seniors and people with disabilities with the first comprehensive prescription drug benefit ever offered under the Medicare program, the...

  7. Prescription Pain Medicines - An Addictive Path?

    Science.gov (United States)

    ... statistics showed that retail sales of five major painkillers rose 90 percent from 1997 to 2005. The report revealed that ever-increasing amounts of prescription painkillers called opioid analgesics are being used on a ...

  8. CDC Vital Signs: Prescription Painkiller Overdoses (Opioids)

    Science.gov (United States)

    ... reporting and access, integration with electronic health records, proactive unsolicited reporting, incentives for provider use, and interoperability ... – Office of Diversion Control Drugs, Brains, and Behavior: The Science of Addiction Prescription Drugs U.S. Food ...

  9. Prescription drug abuse in the elderly.

    Science.gov (United States)

    Martin, Caren McHenry

    2008-12-01

    The increased use of prescription drugs has brought pain relief too many and often improved the quality of life of elderly patients. But the increase in use and availability of prescription medications-especially controlled substances-brings with it an increased potential for abuse. Studies have shown that intentional abuse of prescription drugs is increasing among all age groups. As the number of persons 65 years of age and older skyrockets with the aging of the baby boomers, experts predict that prescription drug abuse among the elderly also will rise significantly. Efforts to increase awareness of drug abuse among elderly patients, caregivers, and health care practitioners, as well as research into how best to prevent and treat the elderly drug abuser, will be necessary to thwart what could become a significant public health problem.

  10. Assessment of prescription sales in Ukraine

    Directory of Open Access Journals (Sweden)

    N. V. Teterich

    2013-10-01

    Full Text Available Currently, the state of the national health system (health is characterized by a low level of funding for medical and pharmaceutical care and the lack of effective methods of free and preferential dispensing of medicines (drugs and compensation of their value. Thus the most urgent problem arises is unregulated drugs prescription, which is one of the main negative factors behind the rapid spread of self-medication and polypragmasy. Thus, improving drugs prescription dispensing is one of the current challenges of medicine and pharmacy management which should be solved to provide a safe, rational and effective drug therapy. The results of the questionnaire survey of doctors and pharmaceutical workers identified and explored key factors that contribute to a violation of drugs prescription. The authors analyzed the literature on the current state of drugs prescription in Ukraine, which resulted in selected priority issues that need resolution as soon as possible. Established that the main disadvantages of the national health care system is unreasonable approach to state regulation of the relevant system and the low level of funding. This situation prevents rational regulation of free and preferential delivery of drugs, the introduction of obligatory medical insurance and the reimbursement cost of drugs and other modern approaches that are effective in developed countries. Тhe main motive of view of legislative acts to implement strict drugs prescription in Ukraine is a link to international experience, guided by the standards of European and international practices that do not comply with the Law of Ukraine issued on 18.03.2004 № 1629-IV «On the National Program for Adaptation of Ukraine to the European Union, "and points to the disparity modern domestic rule-making European practice. The fundamental problem here is the comparison of the legal, social, financial and economic status of the counter in Ukraine with the countries in which the system

  11. Off-label prescriptions in diabetic foot

    OpenAIRE

    Luís Jesuíno de Oliveira Andrade; Larissa Santos França; Paulo Roberto Santana de Melo; Marcelo Araújo

    2014-01-01

    Prescription of a drug outside of the indications for which it was originally approved by regulators is internationally known as "off-label" prescription. We describe off-label treatments for the diabetic foot reported in international scientific literature. This is a qualitative and descriptive bibliographical review based on the results of a search of the Medline international database. The criteria for review were publication between January 1985 and November 2013, and the MeSH (Medical Su...

  12. [Good prescription practice for out-patients-quality requirements of prescriptions in Germany].

    Science.gov (United States)

    Faller, Christine K; Seidling, Hanna M; Haefeli, Walter E

    2014-06-01

    Because the written prescription is a central communication medium between the prescribing physician and the dispensing pharmacist measures to improve the prescription quality are top priorities. While most primary care physicians in Germany use electronic systems, in outpatient clinics and nursing homes and on special occasions such as emergency services and home visits, many prescriptions are still handwritten. Incorrectly and illegibly issued prescriptions impair the physician-pharmacist-patient relationship and thus represent a risk factor in the context of medication safety. Well issued prescriptions expedite the dispensing and thus the continuity of treatment of the patients and spare human resources by avoiding queries and unnecessary steps in the care process. At the same time, legible and unequivocal prescriptions facilitate measures for quality assurance by the dispensing pharmacists and are essential preconditions needed for insurance reimbursement. Probably the most important step to high quality prescriptions is the consistent use of suitable electronic prescription software. This is only possible if physicians are willing to cooperate and understand the significance and benefits of an electronic prescription system.

  13. Impact of a Mandatory Prescription Drug Monitoring Program on Prescription of Opioid Analgesics by Dentists.

    Science.gov (United States)

    Rasubala, Linda; Pernapati, Lavanya; Velasquez, Ximena; Burk, James; Ren, Yan-Fang

    2015-01-01

    Prescription Drug Monitoring Programs (PDMP) are statewide databases that collect data on prescription of controlled substances. New York State mandates prescribers to consult the PDMP registry before prescribing a controlled substance such as opioid analgesics. The effect of mandatory PDMP on opioid drug prescriptions by dentists is not known. This study investigates the impact of mandatory PDMP on frequency and quantity of opioid prescriptions by dentists in a dental urgent care center. Based on the sample size estimate, we collected patient records of a 3-month period before and two consecutive 3-month periods after the mandatory PDMP implementation and analyzed the data on number of visits, treatment types and drug prescriptions using Chi-square tests. For patients who were prescribed pain medications, 452 (30.6%), 190 (14.1%), and 140 (9.6%) received opioid analgesics in the three study periods respectively, signifying a statistically significant reduction in the number of opioid prescriptions after implementation of the mandatory PDMP (pPrescriptions for non-opioid analgesics acetaminophen increased during the same periods (pprescription pattern for pain medications by dentists. Such change in prescription pattern represents a shift towards the evidence-based prescription practices for acute postoperative pain.

  14. Earth Abides Arsenic Biotransformations

    OpenAIRE

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2014-01-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology ...

  15. Effect of rare-earth elements on nanophase evolution, crystallization behaviour and mechanical properties in Al–Ni–R (R = La/Mischmetal) amorphous alloys

    Indian Academy of Sciences (India)

    K L Sahoo; Amitava Mitra; Sukomal Ghosh

    2005-10-01

    The crystallization behaviour and evolution of nanoparticles in amorphous Al–Ni–Mischmetal (Mm) and Al–Ni–La alloys during heat treatment have been studied. Rapidly solidified ribbons were obtained by induction melting and ejecting the melt onto a rotating Cu wheel in an Ar atmosphere. The crystallization behaviour of the melt-spun ribbons was investigated using differential scanning calorimetry and X-ray diffractometry (XRD). XRD studies confirmed that all the ribbons were fully amorphous. Al–Ni–Mm systems showed a three-stage crystallization process whereas Al–Ni–La system, in general, showed a two-stage crystallization process on annealing. Crystallization kinetics was analysed by Kissinger and Johnson–Mehl–Avrami approaches. In Al–Ni–La alloys, the crystallization pathways depend on the La concentration. Microhardness of all the ribbons was examined at different temperatures and correlated with the corresponding evolution of phases.

  16. Earth\\'s Mass Variability

    CERN Document Server

    Mawad, Ramy

    2014-01-01

    The perturbation of the Earth caused by variability of mass of Earth as additional reason with gravity of celestial bodies and shape of the Earth. The Earth eating and collecting matters from space and loss or eject matters to space through its flying in the space around the Sun. The source of the rising in the global sea level is not closed in global warming and icebergs, but the outer space is the additional important source for this rising. The Earth eats waters from space in unknown mechanism. The mass of the Earth become greater in November i.e. before transit apoapsis two months, and become latter in February i.e. after transit apoapsis to two months.

  17. Importance of the Small-Scale Processes Melting, Plate Boundary Formation and Mineralogy on the Large-Scale, Long-Term Thermo-Chemical Evolution of Earth's Mantle-Plate System

    Science.gov (United States)

    Tackley, P.

    2015-12-01

    Seismic observations of the deep Earth reveal the presence of two large low shear velocity provinces (LLSVPs) that are typically inferred to be dense chemically-distinct material, as well as discontinuities that are typically linked to the post-perovskite (pPv) phase transition. Several possible origins of chemically-dense material have been proposed, including recycling of mid-ocean ridge basalt (MORB), primordial differentiation events, crystallisation of a basal magma ocean, or some combination of these creating a basal melange (BAM; Tackley 2012 Earth Sci. Rev.). Each of these possibilities would result in a different composition hence different mineralogy. In order to constrain this we have been running calculations of thermo-chemical mantle evolution over 4.5 billion years that include melting-induced differentiation, plate tectonics induced by strongly temperature-dependent viscosity and plastic yielding, core cooling and compressibility with reasonable assumptions about the pressure-dependence of other material properties. Some of our simulations start from a magma ocean state so initial layering is developed self-consistently. Already-published results (Nakagawa et al., 2009 GCubed, 2010 PEPI, 2012 GCubed) already indicate the importance of exact MORB composition on the amount of MORB segregating above the CMB, which in turn influences mantle thermal structure and the evolution of the core and geodynamo. In more recent results we have been additionally including primordial material. We find that melting-induced differentiation has several first-order effects on the dynamics, including (i) making plate tectonics easier (through stresses associated with lateral variations in crustal thickness) and (ii) reducing heat flux through the CMB (due to the build-up of dense material above the CMB); also (iii) tectonic mode (continuous plate tectonics, episodic lid or stagnant lid) also makes a first-order difference to mantle structure and dynamics. This emphasises

  18. Evolution of Cosmic-Ray Intensities While the Earth Was Engulfed by the Interplanetary Storm (Blob) of 1 - 3 October 2013

    Science.gov (United States)

    Kane, R. P.

    2014-07-01

    When a Coronal Mass Ejection (CME) is ejected by the Sun, it reaches the Earth orbit in a modified state and is called an ICME (Interplanetary CME). When an ICME blob engulfs the Earth, short-scale cosmic-ray (CR) storms (Forbush decreases, FDs) occur, sometimes accompanied by geomagnetic Dst storms, if the B z component in the blob is negative. Generally, this is a sudden process that causes abrupt changes. However, sometimes before this abrupt change (FD) due to strong ICME blobs, there are slow, small changes in interplanetary parameters such as steady increases in solar wind speed V, which are small, but can last for several hours. In the present communication, CR changes in such an event are illustrated in the period 1 - 3 October 2013, when V increased steadily from ˜ 200 km s-1 to ˜ 400 km s-1 during 24 hours on 1 October 2013. The CR intensities decreased by 1 - 2 % during some hours of this 24-hour interval, indicating that CR intensities do respond to these weak but long-lasting increases in interplanetary solar wind speed.

  19. Antibiotic Prescription in Danish General Practice

    DEFF Research Database (Denmark)

    Sydenham, Rikke Vognbjerg; Plejdrup Hansen, Malene; Pedersen, Line Bjørnskov

    2016-01-01

    will explore how the GPs prescription behaviour is influenced by selected factors. Antibiotics are essential when treating potentially lethal infections. An increasing development of resistant bacteria is considered one of the primary threats to public health. The majority of antibiotics (90%) are prescribed...... from general practice. The prescription of broad-spectrum antibiotics can cause unnecessary side effects for the individual and increases the risk of development of bacteria resistant to antibiotic treatment. Both the prescription of broad-spectrum antibiotics and the level of resistant bacteria......1. Background & Aim The overall aim of the project is to describe antibiotic consumption in Danish general practice with emphasis on specific types of antibiotics. The project will shed light on the impact of microbiological diagnostic methods (MDM) on the choice of antibiotic and the project...

  20. Slim accretion discs with different viscosity prescriptions

    Energy Technology Data Exchange (ETDEWEB)

    Szuszkiewicz, E. (Max-Planck-Institut fuer Physik und Astrophysik, Garching (Germany, F.R.). Inst. fuer Astrophysik)

    1990-05-15

    The variability of X-ray sources powered by accretion may be connected to thermal instabilities in the innermost parts of slim discs. The time-scales of variability predicted by the theory with the standard {alpha}-viscosity prescription agree with those observed in a wide range of sources. The amplitudes (3-4 orders of magnitude in luminosity) are correctly predicted for X-ray transient sources, but in general are too big for quasars, Seyferts, galactic black hole candidates and LMXBs. We show here that a slight modification of the viscosity prescription can offer a much better agreement with observations. (author).

  1. The law on electronic medical prescriptions

    Directory of Open Access Journals (Sweden)

    Francis de Clippele

    2005-01-01

    Full Text Available Health care is one of the most important economic and business areas. The European Union has therefore worked out an e-health care strategy to achieving stronger growth and increased effectiviness of services. The application of information and communications technologies (ICT that affect the health care sector, is developing fast in Europe. In this respect various countries have launched pilot projects in order to modernize their medical prescription practices. A model of the electronic medical prescription must respect patient's rights and can only be deployed in a system of security in order to protect the confidentiality.

  2. On prescription-syndrome correspondence of classic prescriptions%认识经方方证

    Institute of Scientific and Technical Information of China (English)

    冯世纶

    2013-01-01

    This paper presents some considerations on prescription-syndrome correspondence of classic prescription.Prescription-syndrome is the basic structure of Treatise on Febrile and Miscellaneous Disease and originates from Shennong era.The accumulation of application experience of prescription-syndrome produces six meridian differentiation.What' s more, the theoretical basis of prescription correspondence to syndrome is eight principal syndromes, and prescription correspondence to syndrome includes the correspondence of prescription and syndrome, herb dosage and disorder severity, decoction-administration methods and disease condition.%介绍对经方方证的几点认识.认为方证是《伤寒杂病论》的基本构成,其形成起源于神农时代,方证应用经验的积累促使六经辨证的产生;方证相应的基础理论是八纲,方证是辨证的尖端,方证相应包括方与证对应、药量与病情对应、煎服法与病情对应.

  3. Research program for a search of the origin of Darwinian evolution. Research program for a vesicle-based model of the origin of Darwinian evolution on prebiotic early Earth

    Science.gov (United States)

    Tessera, Marc

    2017-03-01

    The search for origin of `life' is made even more complicated by differing definitions of the subject matter, although a general consensus is that an appropriate definition should center on Darwinian evolution (Cleland and Chyba 2002). Within a physical approach which has been defined as a level-4 evolution (Tessera and Hoelzer 2013), one mechanism could be described showing that only three conditions are required to allow natural selection to apply to populations of different system lineages. This approach leads to a vesicle- based model with the necessary properties. Of course such a model has to be tested. Thus, after a brief presentation of the model an experimental program is proposed that implements the different steps able to show whether this new direction of the research in the field is valid and workable.

  4. Research program for a search of the origin of Darwinian evolution : Research program for a vesicle-based model of the origin of Darwinian evolution on prebiotic early Earth.

    Science.gov (United States)

    Tessera, Marc

    2017-03-01

    The search for origin of 'life' is made even more complicated by differing definitions of the subject matter, although a general consensus is that an appropriate definition should center on Darwinian evolution (Cleland and Chyba 2002). Within a physical approach which has been defined as a level-4 evolution (Tessera and Hoelzer 2013), one mechanism could be described showing that only three conditions are required to allow natural selection to apply to populations of different system lineages. This approach leads to a vesicle- based model with the necessary properties. Of course such a model has to be tested. Thus, after a brief presentation of the model an experimental program is proposed that implements the different steps able to show whether this new direction of the research in the field is valid and workable.

  5. Mystery Written on Prescription Pads: Exploring Marketing Factors Influencing Prescription Behaviour using the AHP Approach

    Directory of Open Access Journals (Sweden)

    Hemant Bamoriya

    2012-12-01

    Full Text Available The Indian Pharma market is highly fragmented & nature of competition is intense. Further, in modern times influencing doctors’ prescription decision has become very complex as there is little systematic knowledge about factors affecting the doctors’ prescription behaviour and the weight of individual factor. This study aims to demystify this complex prescription behaviour of doctors, through examining the above mentioned factors. For this purpose, a focus group study will be followed by a quantitative study using the Analytic Hierarchy Process (AHP approach. The findings of the study will have important implications for the marketers in order to do proper allocation of their resources, to improve their promotional efficiency.

  6. The Rhynie hot-spring system: implications for the Devonian timescale, development of Devonian biota, gold mineralization, evolution of the atmosphere and Earth outgassing

    Science.gov (United States)

    Mark, D.; Rice, C.; Stuart, F.; Trewin, N.

    2011-12-01

    than the modern air value (Lee et al., 2006). Thus the Earth's atmosphere has accumulated at least 5 ± 0.2 x 1016 moles of 40Ar in the last c. 407 Ma, at an average rate of 1.24 ± 0.06 x 108 mol 40Ar/year. This overlaps the 40Ar accumulation rate determined from ice cores for the last 800,000 years (Bender et al. 2008) and implies that there has been no resolvable temporal change in outgassing rate since the mid-Palaeozoic. The new chronological and Ar isotope data provide a unique tie point and dictate outgassing of the Earth's interior early in Earth history. [1] Bender, M. et al. (2008) Proceedings of the National Academy of Sciences, 105, 8232-8237. [2] Wellman, C.H., 2004. Proceedings of the Royal Society of London. Biological Sciences, 271, 985-992. [3] Lee, J.Y. et al. (2006) Geochimica et Cosmochimica Acta, 70, 4507-4512. [4] Mark, D.F. et al. (2011) Geochimica et Cosmochimica Acta, 75, 555-569. [5] Parry, S.F. et al. (2011) Journal of the Geological Society, London, 168, 863-872. [6] Rice, C.M. et al. (1995) Journal of the Geological Society, London, 152, 229-2250.

  7. Linguistic Prescription: Familiar Practices and New Perspectives.

    Science.gov (United States)

    Finegan, Edward

    2003-01-01

    Reports on a question by a law student of whether a correction of "sneaked" to "snuck" suggests misinformation and misguided rigidity in the context of better information about current legal usage and a perennial tendency to linguistic prescription. Explores attitudes to current borrowings from English into Japanese and French and distinguishes…

  8. 76 FR 51310 - Branded Prescription Drug Fee

    Science.gov (United States)

    2011-08-18

    ... Act (ACA). The regulations affect persons engaged in the business of manufacturing or importing... Clearance Officer, SE:W:CAR:MP:T:T:SP, Washington, DC 20224. Comments on the collection of information... business of manufacturing or importing branded prescription drugs by section 9008 of the ACA. The text of...

  9. An Expert System for Designing Fire Prescriptions

    Science.gov (United States)

    Elizabeth Reinhardt

    1987-01-01

    Managers use prescribed fire to accomplish a variety of resource objectives. The knowledge needed to design successful prescriptions is both quantitative and qualitative. Some of it is available through publications and computer programs, but much of the knowledge of expert practitioners has never been collected or published. An expert system being developed at the,...

  10. The Prescription Opioid Pain Medication Overdose Epidemic

    Centers for Disease Control (CDC) Podcasts

    2016-04-19

    Overdose related to prescription opioids has become an epidemic. This podcast discusses the risks of this type of drug sometimes used to treat pain, and how to protect yourself. .  Created: 4/19/2016 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 4/19/2016.

  11. Respiratory infection and antibiotic prescription rates.

    NARCIS (Netherlands)

    Otters, H.; Wouden, J. van der; Schellevis, F.

    2004-01-01

    In the October issue of the BJGP, Fleming et al showed that a decrease in antibiotic prescription rates is directly related to a decrease in respiratory infections presented in general practice. We compliment the authors for their interesting study and the clear presentation of their results.

  12. Prescriptions Guiding Prospective Teachers in Teaching Mathematics

    Science.gov (United States)

    Zembat, Ismail Özgür; Aslan, Mustafa

    2016-01-01

    This study aims to investigate the nature of different mathematics teaching modes (prescriptions) that guide prospective teachers during their instruction. The participants were 24 junior prospective middle school mathematics teachers (19 females and 5 males) who were attending a mathematics methods course at a private university in central…

  13. COLOR PRESCRIPTION FORM FOR COSMETIC GLOVES

    Science.gov (United States)

    A technique is described for achieving more custom-like coloring of cosmetic gloves. The method involves the use of a color prescription form which...can be used to describe in greater detail the characteristics of those portions of the human hand of greater cosmetic significance.

  14. Preparing for a Hurricane: Prescription Medications

    Centers for Disease Control (CDC) Podcasts

    2006-08-10

    What you should do to protect yourself and your family from a hurricane. As you evacuate, remember to take your prescription medicines with you.  Created: 8/10/2006 by Emergency Communications System.   Date Released: 7/17/2008.

  15. Closing the Prescription Drug Coverage Gap

    Science.gov (United States)

    ... drugs they make are covered during the coverage gap for that calendar year. This includes prescription drugs on the plan’s formulary ( ... you pay for generic drugs during the coverage gap will decrease each year until it reaches 25% in 2020. The coverage ...

  16. New patient asking for a benzodiazepine prescription

    Institute of Scientific and Technical Information of China (English)

    Simon de Lusignan; Andy Kent

    2008-01-01

    @@ Your final patient on a Friday is a 26 year old man who is new to the list. He asks you for a repeat prescription for two months of diazepam, 5 mg up to four a day. He says he has been taking these for a whil for his "newves" and he has run out. You do not hold this patient's records.

  17. A numerical method based on the Fourier-Fourier transform approach for modeling 1-D electron plasma evolution. [in earth bow shock region

    Science.gov (United States)

    Klimas, A. J.

    1983-01-01

    A numerical method is presented for studying one-dimensional electron plasma evolution under typical interplanetary conditions. The method applies the Fourier-Fourier transform approach to a plasma model that is a generalization of the electrostatic Vlasov-Poisson system of equations. Conservation laws that are modified to include the plasma model generalization and also the boundary effects of nonperiodic solutions are given. A new conservation law for entropy in the transformed space is then introduced. These conservation laws are used to verify the numerical solutions. A discretization error analysis is presented. Two numerical instabilities and the methods used for their suppression are treated. It is shown that in interplanetary plasma conditions, the bump-on-tail instability produces significant excitation of plasma oscillations at the Bohm-Gross frequency and its second harmonic. An explanation of the second harmonic excitation is given in terms of wave-wave coupling during the growth phase of the instability.

  18. A paleogeographic approach to aerosol prescription in simulations of deep time climate

    Directory of Open Access Journals (Sweden)

    Nicholas Gray Heavens

    2012-11-01

    Full Text Available Aerosols have important effects on the Earth's radiative balance and are normally included in simulations of present day climate. For simulations of present day or recent past climates, observational information can be used to constrain spatiotemporal variability in aerosol loading. For the deep past, aerosol changes are generally ignored. Here we describe how to use the Community Climate System Model version 4 (CCSM4, standard boundary conditions for a deep time climate simulation, and pre-industrial emissions information to generate a “paleogeographic” aerosol prescription. This prescription is then applied to a previously published simulation of the Late Permian (251 Ma to evaluate the how the model climate is affected by the new aerosol prescription relative to the aerosol distribution originally imposed. The new aerosol prescription results in a broadly warmer and wetter climate with a somewhat stronger Pangaean monsoon. Using spatiotemporally varying and speciated aerosol is equivalent to reducing the optical depth of a uniform background aerosol with sulfate-like properties by ∼30–50%.

  19. Earth materials and earth dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, K; Shankland, T. [and others

    2000-11-01

    In the project ''Earth Materials and Earth Dynamics'' we linked fundamental and exploratory, experimental, theoretical, and computational research programs to shed light on the current and past states of the dynamic Earth. Our objective was to combine different geological, geochemical, geophysical, and materials science analyses with numerical techniques to illuminate active processes in the Earth. These processes include fluid-rock interactions that form and modify the lithosphere, non-linear wave attenuations in rocks that drive plate tectonics and perturb the earth's surface, dynamic recrystallization of olivine that deforms the upper mantle, development of texture in high-pressure olivine polymorphs that create anisotropic velocity regions in the convecting upper mantle and transition zone, and the intense chemical reactions between the mantle and core. We measured physical properties such as texture and nonlinear elasticity, equation of states at simultaneous pressures and temperatures, magnetic spins and bonding, chemical permeability, and thermal-chemical feedback to better characterize earth materials. We artificially generated seismic waves, numerically modeled fluid flow and transport in rock systems and modified polycrystal plasticity theory to interpret measured physical properties and integrate them into our understanding of the Earth. This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL).

  20. Half of Opioid Prescriptions Go to People with Mental Illness

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_167031.html Half of Opioid Prescriptions Go to People With Mental Illness Those ... disorders receive a troubling percentage of the nation's opioid prescriptions, a new study finds. Of the 115 ...

  1. U.S. Opioid Prescriptions Fall, But Numbers Still High

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_167050.html U.S. Opioid Prescriptions Fall, But Numbers Still High: CDC And ... THURSDAY, July 6, 2017 (HealthDay News) -- Prescriptions for opioid painkillers have dropped since 2010 in the United ...

  2. Medical prescription pitfalls of uncomplicated urinary tract infections ...

    African Journals Online (AJOL)

    user

    identify pitfalls in medical prescriptions of uncomplicated .... encourage laboratory tests to support antibiotic drug treatment. ... relevant systems such as prescriptions monitoring and adverse drug ... registration house officer year: how prepared.

  3. Prescription patterns and treatment outcomes of hypertension in ...

    African Journals Online (AJOL)

    Prescription patterns and treatment outcomes of hypertension in urban hospitals of Jos, Plateau State. ... Nigerian Journal of Pharmaceutical Research ... Results of this study revealed several rational and non-rational prescription practices in ...

  4. Abuse of Prescription (Rx) Drugs Affects Young Adults Most

    Science.gov (United States)

    ... Affects Young Adults Most Abuse of Prescription (Rx) Drugs Affects Young Adults Most Email Facebook Twitter Text Description of Infographic Young adults (age 18 to 25) are the biggest abusers of prescription (Rx) opioid pain relievers, ADHD stimulants, ...

  5. Prescription patterns of general practitioners in peshawar, pakistan

    National Research Council Canada - National Science Library

    Raza, Usman Ahmad; Khursheed, Tayyeba; Irfan, Muhammad; Abbas, Maryam; Irfan, Uma Maheswari

    2014-01-01

    To find out prescription patterns of general practitioners in Peshawar. Cross-sectional survey of drug prescriptions was done at six major hospitals and pharmacies of Peshawar between April and May 2011...

  6. Strategies Used by Adults to Reduce Their Prescription Drug Costs

    Science.gov (United States)

    ... Order from the National Technical Information Service NCHS Strategies Used by Adults to Reduce Their Prescription Drug ... Interview Survey, alternative therapies, medication Adults used several strategies to reduce prescription drug costs. Figure 1. Percentages ...

  7. Prescription Drug Plan Formulary, Pharmacy Network, and P...

    Data.gov (United States)

    U.S. Department of Health & Human Services — These public use files contain formulary, pharmacy network, and pricing data for Medicare Prescription Drug Plans and Medicare Advantage Prescription Drug Plans...

  8. 76 FR 17137 - Pregnancy and Prescription Medication Use Symposium

    Science.gov (United States)

    2011-03-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Pregnancy and Prescription Medication Use Symposium AGENCY... announcing the following meeting: Pregnancy and Prescription Medication Use Symposium. The topic to...

  9. Potentially inappropriate prescriptions in patients admitted to a psychiatric hospital

    DEFF Research Database (Denmark)

    Soerensen, Ann Lykkegaard; Nielsen, Lars Peter; Poulsen, Birgitte Klindt

    2016-01-01

    the most frequent PIP. Predictive factors for PIP were polypharmacy (>5 prescriptions) and having one or more somatic diagnoses. Conclusion PIP is common in psychiatric patients and potentially fatal. Particularly polypharmacy (>5 prescriptions) and concomitant somatic illness were associated...

  10. Prescription, dispensation and marketing patterns of methylphenidate

    Science.gov (United States)

    Perini, Edson; Junqueira, Daniela Rezende Garcia; Lana, Lorena Gomes Cunha; Luz, Tatiana Chama Borges

    2014-01-01

    OBJECTIVE To analyze the patterns and legal requirements of methylphenidate consumption. METHODS We conducted a cross-sectional study of the data from prescription notification forms and balance lists of drugs sales – psychoactive and others – subject to special control in the fifth largest city of Brazil, in 2006. We determined the defined and prescribed daily doses, the average prescription and dispensation periods, and the regional sales distribution in the municipality. In addition, we estimated the costs of drug acquisition and analyzed the individual drug consumption profile using the Lorenz curve. RESULTS The balance lists data covered all notified sales of the drug while data from prescription notification forms covered 50.6% of the pharmacies that sold it, including those with the highest sales volumes. Total methylphenidate consumption was 0.37 DDD/1,000 inhabitants/day. Sales were concentrated in more developed areas, and regular-release tablets were the most commonly prescribed pharmaceutical formulation. In some regions of the city, approximately 20.0% of the prescriptions and dispensation exceeded 30 mg/day and 30 days of treatment. CONCLUSIONS Methylphenidate was widely consumed in the municipality and mainly in the most developed areas. Of note, the consumption of formulations with the higher abuse risk was the most predominant. Both its prescription and dispensation contrasted with current pharmacotherapeutic recommendations and legal requirements. Therefore, the commercialization of methylphenidate should be monitored more closely, and its use in the treatment of behavioral changes of psychological disorders needs to be discussed in detail, in line with the concepts of the quality use of medicines. PMID:26039389

  11. Prescription, dispensation and marketing patterns of methylphenidate.

    Science.gov (United States)

    Perini, Edson; Junqueira, Daniela Rezende Garcia; Lana, Lorena Gomes Cunha; Luz, Tatiana Chama Borges

    2014-12-01

    OBJECTIVE To analyze the patterns and legal requirements of methylphenidate consumption. METHODS We conducted a cross-sectional study of the data from prescription notification forms and balance lists of drugs sales - psychoactive and others - subject to special control in the fifth largest city of Brazil, in 2006. We determined the defined and prescribed daily doses, the average prescription and dispensation periods, and the regional sales distribution in the municipality. In addition, we estimated the costs of drug acquisition and analyzed the individual drug consumption profile using the Lorenz curve. RESULTS The balance lists data covered all notified sales of the drug while data from prescription notification forms covered 50.6% of the pharmacies that sold it, including those with the highest sales volumes. Total methylphenidate consumption was 0.37 DDD/1,000 inhabitants/day. Sales were concentrated in more developed areas, and regular-release tablets were the most commonly prescribed pharmaceutical formulation. In some regions of the city, approximately 20.0% of the prescriptions and dispensation exceeded 30 mg/day and 30 days of treatment. CONCLUSIONS Methylphenidate was widely consumed in the municipality and mainly in the most developed areas. Of note, the consumption of formulations with the higher abuse risk was the most predominant. Both its prescription and dispensation contrasted with current pharmacotherapeutic recommendations and legal requirements. Therefore, the commercialization of methylphenidate should be monitored more closely, and its use in the treatment of behavioral changes of psychological disorders needs to be discussed in detail, in line with the concepts of the quality use of medicines.

  12. Literacy and misunderstanding prescription drug labels.

    Science.gov (United States)

    Davis, Terry C; Wolf, Michael S; Bass, Pat F; Thompson, Jason A; Tilson, Hugh H; Neuberger, Marolee; Parker, Ruth M

    2006-12-19

    Health literacy has increasingly been viewed as a patient safety issue and may contribute to medication errors. To examine patients' abilities to understand and demonstrate instructions found on container labels of common prescription medications. Cross-sectional study using in-person, structured interviews. 3 primary care clinics serving mostly indigent populations in Shreveport, Louisiana; Jackson, Michigan; and Chicago, Illinois. 395 English-speaking adults waiting to see their providers. Correct understanding of instructions on 5 container labels; demonstration of 1 label's dosage instructions. Correct understanding of the 5 labels ranged from 67.1% to 91.1%. Patients reading at or below the sixth-grade level (low literacy) were less able to understand all 5 label instructions. Although 70.7% of patients with low literacy correctly stated the instructions, "Take two tablets by mouth twice daily," only 34.7% could demonstrate the number of pills to be taken daily. After potential confounding variables were controlled for, low (adjusted relative risk, 2.32 [95% CI, 1.26 to 4.28]) and marginal (adjusted relative risk, 1.94 [CI, 1.14 to 3.27]) literacy were significantly associated with misunderstanding. Taking a greater number of prescription medications was also statistically significantly associated with misunderstanding (adjusted relative risk, 2.98 [CI, 1.40 to 6.34] for > or =5 medications). The study sample was at high risk for poor health literacy and outcomes. Most participants were women, and all spoke English. The authors did not examine the association between misunderstanding and medication error or evaluate patients' actual prescription drug-taking behaviors. Lower literacy and a greater number of prescription medications were independently associated with misunderstanding the instructions on prescription medication labels.

  13. Prescription, dispensation and marketing patterns of methylphenidate

    Directory of Open Access Journals (Sweden)

    Edson Perini

    2014-12-01

    Full Text Available OBJECTIVE To analyze the patterns and legal requirements of methylphenidate consumption. METHODS We conducted a cross-sectional study of the data from prescription notification forms and balance lists of drugs sales – psychoactive and others – subject to special control in the fifth largest city of Brazil, in 2006. We determined the defined and prescribed daily doses, the average prescription and dispensation periods, and the regional sales distribution in the municipality. In addition, we estimated the costs of drug acquisition and analyzed the individual drug consumption profile using the Lorenz curve. RESULTS The balance lists data covered all notified sales of the drug while data from prescription notification forms covered 50.6% of the pharmacies that sold it, including those with the highest sales volumes. Total methylphenidate consumption was 0.37 DDD/1,000 inhabitants/day. Sales were concentrated in more developed areas, and regular-release tablets were the most commonly prescribed pharmaceutical formulation. In some regions of the city, approximately 20.0% of the prescriptions and dispensation exceeded 30 mg/day and 30 days of treatment. CONCLUSIONS Methylphenidate was widely consumed in the municipality and mainly in the most developed areas. Of note, the consumption of formulations with the higher abuse risk was the most predominant. Both its prescription and dispensation contrasted with current pharmacotherapeutic recommendations and legal requirements. Therefore, the commercialization of methylphenidate should be monitored more closely, and its use in the treatment of behavioral changes of psychological disorders needs to be discussed in detail, in line with the concepts of the quality use of medicines.

  14. CHEMICAL EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, Melvin

    1965-06-01

    How did life come to be on the surface of the earth? Darwin himself recognized that his basic idea of evolution by variation and natural selection must be a continuous process extending backward in time through that period in which the first living things arose and into the period of 'Chemical Evolution' which preceded it. We are approaching the examination of these events by two routes. One is to seek for evidence in the ancient rocks of the earth which were laid down prior to that time in which organisms capable of leaving their skeletons in the rocks to be fossilized were in existence. This period is sometime prior to approximately 600 million years ago. The earth is believed to have taken its present form approximately 4700 million years ago. We have found in rocks whose age is about 1000 million years certain organic molecules which are closely related to the green pigment of plants, chlorophyll. This seems to establish that green plants were already fluorishing prior to that time. We have now found in rocks of still greater age, namely, 2500 million years, the same kinds of molecules mentioned above which can be attributed to the presence of living organisms. If these molecules are as old as the rocks, we have thus shortened the time available for the generation of the complex biosynthetic sequences which give rise to these specific hydrocarbons (polyisoprenoids) to less than 2000 million years.

  15. Irrational drug use in India: A prescription survey from Goa

    Directory of Open Access Journals (Sweden)

    Naik D

    2005-01-01

    Full Text Available BACKGROUND: There is concern regarding the irrational production, prescription and use of drugs in India. This study aimed to describe the quality of prescriptions by medical practitioners, including both the layout of the prescription and the type and number of drugs prescribed. MATERIALS AND METHODS: A survey of all prescriptions dispensed at a busy pharmacy in the state of Goa, India, was carried out over a consecutive seven-day period. Each prescription was rated on the basis of a priori and pilot-tested variable list. The prescriptions by private practitioners were compared with those from practitioners in the public healthcare system. RESULTS: Nine hundred and ninety prescriptions were collected. The majority (83.9% were from private practitioners. The quality of the layout of the prescriptions was unsatisfactory: information to identify the practitioner was incomplete in more than a third of the prescriptions and information to identify the patient was incomplete in more than half. Clarity of written instructions on how to take the medicines was unsatisfactory in the majority of prescriptions. Polypharmacy was the norm, with more than half (52.7% the prescriptions containing at least 3 medicines. Forty per cent of prescriptions included a vitamin or tonic preparation and a quarter of the prescriptions included an antibiotic and an analgesic. Over 90% of prescriptions contained only branded medicines. Private practitioners prescribed significantly greater number of medicines and were more likely to prescribe vitamins and antibiotics, and branded medicines. DISCUSSION: This study confirms that the quality of prescriptions, both in terms of layout and the content of the drugs prescribed, is inadequate. There is a need to standardize the format of prescriptions in India so that all essential information is included. There is a need to strengthen an independent mechanism for continuing professional development of practitioners to ensure that

  16. Exercise on Prescription: trial protocol and evaluation of outcomes

    OpenAIRE

    Puggaard Lis; Kjær Kirsten; Kragstrup Jakob; Sørensen Jes B

    2007-01-01

    Abstract Background In many countries exercise prescriptions are used in an attempt to initiate a physically active lifestyle in sedentary populations. Previous studies have primarily evaluated low intensive exercise prescription interventions and found moderately positive effects on physical activity and aerobic fitness. In a highly intensive Danish exercise prescription scheme called 'Exercise on Prescription' (EoP) the general practitioners can prescribe EoP to sedentary patients with life...

  17. 21 CFR 202.1 - Prescription-drug advertisements.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Prescription-drug advertisements. 202.1 Section...) DRUGS: GENERAL PRESCRIPTION DRUG ADVERTISING § 202.1 Prescription-drug advertisements. (a)(1) The... ingredients in the advertisement shall be the same as the order of listing of ingredients on the label of...

  18. The Philosophical Foundations of Prescriptive Statements and Statistical Inference

    Science.gov (United States)

    Sun, Shuyan; Pan, Wei

    2011-01-01

    From the perspectives of the philosophy of science and statistical inference, we discuss the challenges of making prescriptive statements in quantitative research articles. We first consider the prescriptive nature of educational research and argue that prescriptive statements are a necessity in educational research. The logic of deduction,…

  19. Resonant Messages to Prevent Prescription Drug Misuse by Teens

    Science.gov (United States)

    Twombly, Eric C.; Holtz, Kristen D.; Agnew, Christine B.

    2011-01-01

    Prescription drug misuse is a major health problem, particularly among teens. A key step in curbing misuse is the development of effective prescription drug prevention messages. This paper explores the elements of prescription drug misuse prevention messages that resonate with teens using data from focus groups with seventh and eighth grade…

  20. The Philosophical Foundations of Prescriptive Statements and Statistical Inference

    Science.gov (United States)

    Sun, Shuyan; Pan, Wei

    2011-01-01

    From the perspectives of the philosophy of science and statistical inference, we discuss the challenges of making prescriptive statements in quantitative research articles. We first consider the prescriptive nature of educational research and argue that prescriptive statements are a necessity in educational research. The logic of deduction,…

  1. 21 CFR 1306.09 - Prescription requirements for online pharmacies.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Prescription requirements for online pharmacies... PRESCRIPTIONS General Information § 1306.09 Prescription requirements for online pharmacies. (a) No controlled... constitutes dispensing by means of the Internet unless such person is a pharmacist who is acting in the...

  2. Patterns of Prescription Medication Diversion among Drug Dealers

    Science.gov (United States)

    Rigg, Khary K.; Kurtz, Steven P.; Surratt, Hilary L.

    2012-01-01

    This research examined the following questions: (1) how do drug dealers acquire their inventories of prescription medications? and (2) which types of prescription medications do dealers most commonly sell? Data are drawn from a National Institute on Drug Abuse-funded research study that examined prescription drug diversion and abuse in South…

  3. Oxygen isotope perspective on crustal evolution on early Earth: A record of Precambrian shales with emphasis on Paleoproterozoic glaciations and Great Oxygenation Event

    Science.gov (United States)

    Bindeman, I. N.; Bekker, A.; Zakharov, D. O.

    2016-03-01

    We present stable isotope and chemical data for 206 Precambrian bulk shale and tillite samples that were collected mostly from drillholes on all continents and span the age range from 0.5 to 3.5 Ga with a dense coverage for 2.5-2.2 Ga time interval when Earth experienced four Snowball Earth glaciations and the irreversible rise in atmospheric O2. We observe significant, downward shift of several ‰ and a smaller range of δ18 O values (7 to 9‰) in shales that are associated with the Paleoproterozoic and, potentially, Neoproterozoic glaciations. The Paleoproterozoic samples consist of more than 50% mica minerals and have equal or higher chemical index of alteration than overlying and underlying formations and thus underwent equal or greater degrees of chemical weathering. Their pervasively low δ18 O and δD (down to - 85 ‰) values provide strong evidence of alteration and diagenesis in contact with ultra-low δ18 O glacial meltwaters in lacustrine, deltaic or periglacial lake (sikussak-type) environments associated with the Paleoproterozoic glaciations. The δDsilicate values for the rest of Precambrian shales range from -75 to - 50 ‰ and are comparable to those for Phanerozoic and Archean shales. Likewise, these samples have similar ranges in δ13Corg values (-23 to - 33 ‰ PDB) and Corg content (0.0 to 10 wt%) to Phanerozoic shales. Precambrian shales have a large range of δ18 O values comparable to that of the Phanerozoic shales in each age group and formation, suggesting similar variability in the provenance and intensity of chemical weathering, except for the earliest 3.3-3.5 Ga Archean shales, which have consistently lower δ18 O values. Moreover, Paleoproterozoic shales that bracket in age the Great Oxidation Event (GOE) overlap in δ18 O values. Absence of a step-wise increase in δ18 O and δD values suggests that despite the first-order change in the composition of the atmosphere, weathering cycle was not dramatically affected by the GOE at ∼2

  4. Automation System in Rare Earths Countercurrent Extraction Processes

    Institute of Scientific and Technical Information of China (English)

    贾江涛; 严纯华; 廖春生; 吴声; 王明文; 李标国

    2001-01-01

    Based on the countercurrent extraction theory for optimized designing and simulating, the rare earth separation processes, the selection of the detecting points (stages) and on-line analysis for elements, the simulation of open loop response and its response speed, the diagnosis and the regulative prescription for running the solvent extraction cascades were studied.

  5. A European community pharmacy-based survey to investigate patterns of prescription fraud through identification of falsified prescriptions

    NARCIS (Netherlands)

    Lapeyre-Mestre, Maryse; Gony, Mireille; Carvajal, Alfonso; Macias, Diego; Conforti, Anita; D'incau, Paola; Heerdink, Rob; Van Der Stichele, Robert; Bergman, Ulf

    2014-01-01

    Aim: To identify prescription drugs involved in falsified prescriptions in community pharmacies in 6 European countries. Methods: A cross-sectional survey among 2,105 community pharmacies in Belgium, France, Italy, the Netherlands, Spain and Sweden was carried out to collect all suspect prescription

  6. A European community pharmacy-based survey to investigate patterns of prescription fraud through identification of falsified prescriptions

    NARCIS (Netherlands)

    Lapeyre-Mestre, Maryse; Gony, Mireille; Carvajal, Alfonso; Macias, Diego; Conforti, Anita; D'incau, Paola; Heerdink, Rob; Van Der Stichele, Robert; Bergman, Ulf

    2014-01-01

    Aim: To identify prescription drugs involved in falsified prescriptions in community pharmacies in 6 European countries. Methods: A cross-sectional survey among 2,105 community pharmacies in Belgium, France, Italy, the Netherlands, Spain and Sweden was carried out to collect all suspect prescription

  7. MoMa: From Molecules to Man: Space Research Applied to the improvement of the Quality of Life of the Ageing Population on Earth. Evolution of a project

    Science.gov (United States)

    Zambito, Anna Maria; Curcio, Francesco; Meli, Antonella; Saverio Ambesi-Impiombato, Francesco

    The "MoMa" project: "From Molecules to Man: Space Research Applied to the improvement of the Quality of Life of the Ageing Population on Earth started June 16 2006 and finished right on schedule June 25 2009, has been the biggest of the three projects funded by ASI in the sector "Medicine and Biotechnology. In the last years the scientific community had formed a national chain of biomedical spatial research with different research areas. MoMa responds to the necessity of unification in ASI of the two areas "Radiobiology and Protection" and "Cellular and Molecular Biotechnology" in a line of joint research: "Biotechnological Applications" were the interests of all groups would be combined and unified in a goal of social relevance. MoMa is the largest project ever developed in the biomedical area in Italy, the idea was born thinking about the phenomenon of acceleration of the aging process observed in space, and already described in literature, and the aim of studying the effects of the space environment at cellular, molecular and human organism level. "MoMa" was divided into three primary areas of study: Molecules, Cells and Man with an industrial area alongside. This allowed to optimize the work and information flows within the scientific research more similar and more culturally homogeneous and allowed a perfect industrial integration in a project of great scientific importance. Within three scientific areas 10 scientific lines in total are identified, each of them coordinated by a subcontractor. The rapid and efficient exchange of information between different areas of science and the development of industrial applications in various areas of interest have been assured by a strong work of Scientific Coordination of System Engineering and Quality Control. After three years of intense and coordinated activities within the MoMa project, the objectives achieved are very significant not only as regards the scientific results and the important hardware produced but

  8. Serpentinization and the Traces of Origin and Evolution of Life in the Earth%蛇纹石化作用与地球生命起源/演化的痕迹

    Institute of Scientific and Technical Information of China (English)

    王先彬

    2016-01-01

    对蛇纹石化超基性岩寄主生物圈的研究,有望获得地球上古老而独特的前生命/生命有机质成因和演化的重要信息.本文综述了探索火星过去生命和地球古老沉积岩生命起源/演化证据的质疑和争论、相关分析方法和技术的应用.论述了超基性岩蛇纹石化作用生成分子氢,并通过费-托聚合反应生成烷烃的基础理论及其与生命起源/演化的相关性,简述了鉴别蛇纹石化超基性岩中有机质来源的烷烃的碳、氢同位素组成和分布模式,有机质的同位素和分子生物学特征.超基性岩蛇纹石化生成非生物成因烷烃与其他有机化合物,为化能自养微生物群落提供了所需要的能量和初始物质,是生命起源最重要的变质水化反应.超基性岩蛇纹石化作用通常发生在缓慢扩张洋中脊系统、大陆蛇绿岩系统等构造环境.生物过程和非生物过程的叠加,给鉴别蛇纹岩寄主生态系统的生物成因有机质带来严峻挑战.%The origin and evolution of life is the most important and disputable scientific question.Important information a-bout pre-life and life organic compounds in early Earth history could be deduced through the study on the microbial com-munities in serpentinized ultramafic rocks.This paper has comprehensively reviewed the questions and arguments on evi-dences for exploring origin and evolution of ancient life of Mars and sedimentary rocks on earth,and the related analytical methods and technological applications,discussed basic theories on the generation of molecular hydrogen through the ser-pentinization of ultramafic rocks and the generation of alkane through the Fischer-Tropsch Type polymerization of the mo-lecular hydrogen and their relationship to the life's origin and evolution,and briefly discribed the compositions and distri-bution patterns of carbon and hydrogen isotopes of alkane for identifying source of the organic matters in the serpentinized

  9. Life Before Earth

    CERN Document Server

    Sharov, Alexei A

    2013-01-01

    An extrapolation of the genetic complexity of organisms to earlier times suggests that life began before the Earth was formed. Life may have started from systems with single heritable elements that are functionally equivalent to a nucleotide. The genetic complexity, roughly measured by the number of non-redundant functional nucleotides, is expected to have grown exponentially due to several positive feedback factors: gene cooperation, duplication of genes with their subsequent specialization, and emergence of novel functional niches associated with existing genes. Linear regression of genetic complexity on a log scale extrapolated back to just one base pair suggests the time of the origin of life 9.7 billion years ago. This cosmic time scale for the evolution of life has important consequences: life took ca. 5 billion years to reach the complexity of bacteria; the environments in which life originated and evolved to the prokaryote stage may have been quite different from those envisaged on Earth; there was no...

  10. Heat-pipe Earth.

    Science.gov (United States)

    Moore, William B; Webb, A Alexander G

    2013-09-26

    The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics.

  11. [Drug design ideas and methods of Chinese herb prescriptions].

    Science.gov (United States)

    Ren, Jun-guo; Liu, Jian-xun

    2015-09-01

    The new drug of Chinese herbal prescription, which is the best carrier for the syndrome differentiation and treatment of Chinese medicine and is the main form of the new drug research and development, plays a very important role in the new drug research and development. Although there are many sources of the prescriptions, whether it can become a new drug, the necessity, rationality and science of the prescriptions are the key to develop the new drug. In this article, aiming at the key issues in prescriptions design, the source, classification, composition design of new drug of Chinese herbal prescriptions are discussed, and provide a useful reference for research and development of new drugs.

  12. Snowball Earth

    OpenAIRE

    2016-01-01

    In the ongoing quest to better understand where life may exist elsewhere in the Universe, important lessons may be gained from our own planet. In particular, much can be learned from planetary glaciation events that Earth suffered ∼600 million years ago, so-called `Snowball Earth' episodes. I begin with an overview of how the climate works. This helps to explain how the ice-albedo feedback effect can destabilise a planet's climate. The process relies on lower temperatures causing more ice to ...

  13. A polycarbonate ophthalmic-prescription lens series.

    Science.gov (United States)

    Davis, J K

    1978-08-01

    Improvements in polycarbonate material, production techniques, and scratch-resistant coatings, combined with a process-oriented design, have resulted in a precision lens series. Surface quality is comparable to that of untreated glass ophthalmic lenses. The repeatability of the process results in closely controlled axial power and off-axis performance. For most lens prescriptions, the ANSI Z80.1 optical-center specifications for prescription accuracy are maintained through a total field of view of 40 deg for an 8-mm range of center-of-rotation distances. Off-axis astigmatism is controlled for near-point seeing. The lenses are both lighter and thinner than those of crown glass. A scratch-resistant coating reduces the reflections normally associated with high-index (1.586) materials. Impact resistance exceeds that required by ANSI Z80.7 and is many times that required by ANSI Z80.1.

  14. Women who doctor shop for prescription drugs.

    Science.gov (United States)

    Worley, Julie; Thomas, Sandra P

    2014-04-01

    Doctor shopping is a term used to describe a form of diversion of prescription drugs when patients visit numerous prescribers to obtain controlled drugs for illicit use. Gender differences exist in regard to prescription drug abuse and methods of diversion. The purpose of this phenomenological study guided by the existential philosophy of Merleau-Ponty was to understand the lived experience of female doctor shoppers. Interviews were conducted with 14 women, which were recorded, transcribed, and analyzed. Included in the findings are figural aspects of the participants' experience of doctor shopping related to the existential grounds of world, time, body, and others. Four themes emerged from the data: (a) feeding the addiction, (b) networking with addicts, (c) playing the system, and (d) baiting the doctors. The findings suggest several measures that nurses can take to reduce the incidence of doctor shopping and to provide better care for female doctor shoppers.

  15. Information prescriptions: A tool for veterinary practices

    Directory of Open Access Journals (Sweden)

    L.R. Kogan

    2014-09-01

    Full Text Available The Internet has become a major source of health information and has the potential to offer many benefits for both human and animal health. In order for impact to be positive, however, it is critical that users be able to access reliable, trustworthy information. Although more pet owners are using the Internet to research animal health information than ever before, there remains limited research surrounding their online activities or the ability to influence owners’ online search behaviors. The current study was designed to assess the online behaviors and perceptions of pet owners after receiving either general or topic-specific information prescriptions as part of their veterinary appointment. Results indicate that nearly 60% of clients accessed the suggested websites and nearly all of these clients reported positive feelings about this addition to their veterinary services. These results suggest that offering information prescriptions to clients can facilitate better online searches by clients and positively impact both animal health and client satisfaction.

  16. Price Sensitivity of Demand for Prescription Drugs

    DEFF Research Database (Denmark)

    Simonsen, Marianne; Skipper, Lars; Skipper, Niels

    2016-01-01

    We investigate price sensitivity of demand for prescription drugs, using drug purchase records for the entire Danish population. We identify price responsiveness by exploiting variation in prices caused by kinked reimbursement schemes and implement a regression kink design. The results suggest so...... price responsiveness with corresponding price elasticities ranging from −0.2 to −0.7. Individuals with chronic disease and especially individuals above the age of 65 respond less to the price of drugs.......We investigate price sensitivity of demand for prescription drugs, using drug purchase records for the entire Danish population. We identify price responsiveness by exploiting variation in prices caused by kinked reimbursement schemes and implement a regression kink design. The results suggest some...

  17. 钱塘江河口区晚第四纪古环境演化及其元素地球化学特征%PALEOENVIRONMENT EVOLUTION DURING THE LATE QUATERNARY IN THE QIANTANG RIVER MOUTH AREA: EVIDENCE FROM THE SE2 CORE SEDIMENT AND ITS RARE EARTH ELEMENTS GEOCHEMISTRY

    Institute of Scientific and Technical Information of China (English)

    李艳丽; 林春明; 张霞; 周健; 曲长伟; 潘峰; 姚玉来

    2011-01-01

    In 2009, a 51. 5-m-long core SE2 was drilled at 120°21'57" E, 30°12'38" N, from the Kanshan town, Hangzhou city, in the south bank of the Qiantang River. The ground surface elevation of the core is 6. Om above mean sea level. Core SE2,10. 8cm in diameter,was obtained by rotary drilling with a 96% recovery. A total of 294 samples were collected at 10 ~20cm intervals along the cored succession for grain size analysis,93 samples at 20 ~ 80cm intervals for foraminifera identification, and 27 samples at 200cm intervals for rare earth elements analysis. The lithology, grain size, sedimentary structure, foraminifera, and rare earth elements of Late Quaternary sediments in the borehole SE2 were analyzed to research the sedimentary environment evolution, and the associated distribution variation of rare earth elements in the Qiantang River mouth area. The results indicate that five sedimentary facies, including fluvial channel,floodplain,tidal flat,shallow marine,and estuarine sand bar,can be distinguished,and the rare earth elements distribution is closely related to sedimentary environment. Fluvial channel facies consists of sandy gravel,gravelly sand, and fine sand, with high content of rolling and saltation population. Foraminifera are absent. The sediments have the lowest total rare earth elements content in all sedimentary facies,and high light rare earth elements concentration. The fractionation degree of light and heavy rare earth elements, and fractionation degree of heavy rare earth elements are positively related with the total rare earth elements content. The fractionation of light rare earth elements shows negative correlation with the total rare earth elements content, heavy rare earth elements concentration, the fractionation of light and heavy rare earth elements, and fractionation in heavy rare earth elements. Floodplain facies are dominated by clay, with foraminifera and rolling population absent. Total rare earth elements content is the highest. The

  18. Vital Signs-Preventing Prescription Drug Overdose

    Centers for Disease Control (CDC) Podcasts

    2014-07-01

    This podcast is based on the July 2014 CDC Vital Signs report. Every day, 46 people in the U.S. die from an overdose of prescription opioid painkillers. Learn what can be done to make painkiller prescribing safer and help prevent overdoses.  Created: 7/1/2014 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 7/1/2014.

  19. Preventing Prescription Drug Overdose PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2014-07-01

    This 60 second public service announcement is based on the July 2014 CDC Vital Signs report. Every day, 46 people in the U.S. die from an overdose of prescription opioid painkillers. Learn what can be done to make painkiller prescribing safer and help prevent overdoses.  Created: 7/1/2014 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 7/1/2014.

  20. Arts on prescription: a qualitative outcomes study.

    Science.gov (United States)

    Stickley, T; Eades, M

    2013-08-01

    In recent years, participatory community-based arts activities have become a recognized and regarded method for promoting mental health. In the UK, Arts on Prescription services have emerged as a prominent form of such social prescribing. This follow-up study reports on the findings from interviews conducted with participants in an Arts on Prescription programme two years after previous interviews to assess levels of 'distance travelled'. This follow-up study used a qualitative interview method amongst participants of an Arts on Prescription programme of work. Ten qualitative one-to-one interviews were conducted in community-based arts venues. Each participant was currently using or had used mental health services, and had been interviewed two years earlier. Interviews were digitally recorded, transcribed and analysed. For each of the 10 participants, a lengthy attendance of Arts on Prescription had acted as a catalyst for positive change. Participants reported increased self-confidence, improved social and communication skills, and increased motivation and aspiration. An analysis of each of the claims made by participants enabled them to be grouped according to emerging themes: education: practical and aspirational achievements; broadened horizons: accessing new worlds; assuming and sustaining new identities; and social and relational perceptions. Both hard and soft outcomes were identifiable, but most were soft outcomes. Follow-up data indicating progress varied between respondents. Whilst hard outcomes could be identified in individual cases, the unifying factors across the sample were found predominately in the realm of soft outcomes. These soft outcomes, such as raised confidence and self-esteem, facilitated the hard outcomes such as educational achievement and voluntary work. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  1. Price Sensitivity of Demand for Prescription Drugs

    DEFF Research Database (Denmark)

    Skipper, Lars; Simonsen, Marianne; Skipper, Niels

    This paper investigates price sensitivity of demand for prescription drugs using drug purchase records for at 20% random sample of the Danish population. We identify price responsiveness by exploiting exogenous variation in prices caused by kinked reimbursement schemes and implement a regression ...... education and income are, however, more responsive to the price. Also, essential drugs that prevent deterioration in health and prolong life have lower associated average price sensitivity....

  2. Digital Earth - A sustainable Earth

    Science.gov (United States)

    Mahavir

    2014-02-01

    All life, particularly human, cannot be sustainable, unless complimented with shelter, poverty reduction, provision of basic infrastructure and services, equal opportunities and social justice. Yet, in the context of cities, it is believed that they can accommodate more and more people, endlessly, regardless to their carrying capacity and increasing ecological footprint. The 'inclusion', for bringing more and more people in the purview of development is often limited to social and economic inclusion rather than spatial and ecological inclusion. Economic investment decisions are also not always supported with spatial planning decisions. Most planning for a sustainable Earth, be at a level of rural settlement, city, region, national or Global, fail on the capacity and capability fronts. In India, for example, out of some 8,000 towns and cities, Master Plans exist for only about 1,800. A chapter on sustainability or environment is neither statutorily compulsory nor a norm for these Master Plans. Geospatial technologies including Remote Sensing, GIS, Indian National Spatial Data Infrastructure (NSDI), Indian National Urban Information Systems (NUIS), Indian Environmental Information System (ENVIS), and Indian National GIS (NGIS), etc. have potential to map, analyse, visualize and take sustainable developmental decisions based on participatory social, economic and social inclusion. Sustainable Earth, at all scales, is a logical and natural outcome of a digitally mapped, conceived and planned Earth. Digital Earth, in fact, itself offers a platform to dovetail the ecological, social and economic considerations in transforming it into a sustainable Earth.

  3. [Evaluation of quality medication prescription of a teaching hospital].

    Science.gov (United States)

    Araújo, Patrícia Taveira de Brito; Uchôa, Severina Alice Costa

    2011-01-01

    The errors from doctor prescriptions can cause damage to the patient's health, consequently it is necessary to identify and to prevent them. This work aimed to evaluate if the legal and institutional aspects that are present in doctor prescription at the public and university pediatric hospital to make a diagnosis from the situation, and then to correct the problems. A survey was made was made using a cross-sectional method, where copies of 1,590 prescriptions were studied after the University Committee of Research approved the survey. The average was 4.47 drugs per prescription and following data were detectable: readable--32.39% of the prescriptions were unreadable, 49.81% presented only the commercial name, 5.25% of the drugs were not standardized. Quality of prescription in the chosen hospital needs to be better to avoid medication errors and the health care process gets safer. When prescription is unreadable, they can confuse health professionals and damage patients.

  4. Increasing access to emergency contraception through online prescription requests.

    Science.gov (United States)

    Averbach, Sarah; Wendt, Jacqueline Moro; Levine, Deborah K; Philip, Susan S; Klausner, Jeffrey D

    2010-01-01

    To describe a pilot program, Plan B Online Prescription Access, to provide easy access to prescriptions for emergency contraception via the Internet. We measured electronic prescriptions for Plan B (Duramed Pharmaceuticals, Cincinnati, Ohio) by month over time. Pharmacists faxed patient-generated prescriptions back to the Department of Public Health for confirmation. Despite no marketing, within the first 18 months of the program, 152 electronic prescriptions for Plan B were requested by 128 female San Francisco residents. Seventy-eight prescriptions were filled (51%) by pharmacists. If correctly marketed, online prescriptions for Plan B have the potential to be an effective means of increasing emergency contraception access in both urban and rural settings across the United States. Further user-acceptability studies are warranted.

  5. Reviewing prescription spending and accessory usage.

    Science.gov (United States)

    Oxenham, Julie

    This article aims to explore the role of the stoma nurse specialist in the community and how recent initiatives within the NHS have impacted on the roles in stoma care to react to the rising prescription costs in the specialty. The article will explore how the stoma care nurse conducted her prescription reviews within her own clinical commissioning group (CCG). The findings of the reviews will be highlighted by a small case history and a mini audit that reveals that some stoma patients may be using their stoma care accessories inappropriately, which may contribute to the rise in stoma prescription spending. To prevent the incorrect use of stoma appliances it may necessitate an annual review of ostomates (individuals who have a stoma), as the author's reviews revealed that inappropriate usage was particularly commonplace when a patient may have not been reviewed by a stoma care specialist for some considerable amount of time. Initial education of the ostomate and ongoing education of how stoma products work is essential to prevent the misuse of stoma appliances, particularly accessories, as the reviews revealed that often patients were not always aware of how their products worked in practice.

  6. NASA's Earth Science Data Systems

    Science.gov (United States)

    Ramapriyan, H. K.

    2015-01-01

    NASA's Earth Science Data Systems (ESDS) Program has evolved over the last two decades, and currently has several core and community components. Core components provide the basic operational capabilities to process, archive, manage and distribute data from NASA missions. Community components provide a path for peer-reviewed research in Earth Science Informatics to feed into the evolution of the core components. The Earth Observing System Data and Information System (EOSDIS) is a core component consisting of twelve Distributed Active Archive Centers (DAACs) and eight Science Investigator-led Processing Systems spread across the U.S. The presentation covers how the ESDS Program continues to evolve and benefits from as well as contributes to advances in Earth Science Informatics.

  7. Governmental oversight of prescribing medications: history of the US Food and Drug Administration and prescriptive authority.

    Science.gov (United States)

    Plank, Linda S

    2011-01-01

    The evolution of drug regulation and awarding of prescriptive authority is a complex and sometimes convoluted process that can be confusing for health care providers. A review of the history of how drugs have been manufactured and dispensed helps explain why this process has been so laborious and complicated. Because the federal and state governments have the responsibility for protecting the public, most regulations have been passed with the intentions of ensuring consumer safety. The current system of laws and regulations is the result of many years of using the legal system to correct drug marketing that had adverse health consequences. Government oversight will continue as prescribing medications transitions to an electronic form and as health care professionals in addition to physicians seek to gain prescriptive authority.

  8. Prescription Drug Misuse and Sexual Behavior Among Young Adults.

    Science.gov (United States)

    Wells, Brooke E; Kelly, Brian C; Rendina, H Jonathon; Parsons, Jeffrey T

    2015-01-01

    Though research indicates a complex link between substance use and sexual risk behavior, there is limited research on the association between sexual risk behavior and prescription drug misuse. In light of alarming increases in prescription drug misuse and the role of demographic characteristics in sexual risk behavior and outcomes, the current study examined demographic differences (gender, sexual identity, age, relationship status, parental class background, and race/ethnicity) in sexual risk behavior, sexual behavior under the influence of prescription drugs, and sexual risk behavior under the influence of prescription drugs in a sample of 402 young adults (ages 18 to 29) who misused prescription drugs. Nearly half of the sexually active young adult prescription drug misusers in this sample reported recent sex under the influence of prescription drugs; more than three-quarters reported recent sex without a condom; and more than one-third reported recent sex without a condom after using prescription drugs. Zero-inflated Poisson regression models indicated that White race, younger age, higher parental class, and being a heterosexual man were all associated with sexual risk behavior, sex under the influence of prescription drugs, and sexual risk under the influence of prescription drugs. Findings have implications for the targeting of prevention and intervention efforts.

  9. Impact of a prescription monitoring program on doctor-shopping for high dosage buprenorphine.

    Science.gov (United States)

    Pradel, Vincent; Frauger, Elisabeth; Thirion, Xavier; Ronfle, Eléonore; Lapierre, Véronique; Masut, Alain; Coudert, Christine; Blin, Olivier; Micallef, Joëlle

    2009-01-01

    Doctor-shopping (simultaneous use of several physicians by a patient) is one of the most frequent ways of diversion for prescription drugs. A specific method was used to assess the evolution of doctor-shopping for High Dosage Buprenorphine (HDB) in a French region from 2000 to 2005 and the impact of a prescription monitoring program for HDB implemented in 2004. Data from eight periods (semesters of years 2000, 2002, 2004, and 2005) were extracted from a prescription database. Three quantities (the delivered, the prescribed, and the doctor-shopping quantity) were computed for each patient. The total doctor-shopping quantity and the doctor-shopping ratio (percentage of buprenorphine obtained through doctor-shopping) were used to evaluate the diversion of HDB among the population. The total prescribed quantity and the number of patients treated regularly were used as indicators of the access to treatment. The doctor-shopping ratio increased from 1st semester 2000 to 1st semester 2004 (from 14.9 to 21.7%) and then decreased to 16.9% in 2nd semester 2005. The total doctor-shopping quantity followed the same evolution. The number of patients treated remained stable from 1st semester 2000 to 2nd semester 2005. The prescribed quantity increased from 1st semester 2000 to 2nd semester 2002, decreased in 1st semester 2004 (4163 g) and then remained stable. After a four-year increase of the diversion through doctor-shopping for buprenorphine the beginning of the prescription monitoring program was concomitant with a marked decrease of doctor-shopping indicators without notable impact on the access to treatment.

  10. Active Near Earth Asteroids

    Science.gov (United States)

    Jenniskens, Peter

    2015-08-01

    Past activity from Near Earth Asteroids is recorded in the meteoroid streams that cause our meteor showers. Automated meteoroid orbit surveys by photographic, low-light video, specular radar, and head-echo radar reflections are providing the first maps of meteor shower activity at different particle sizes. There are distinct differences in particle size distributions among streams. The underlaying mechanisms that created these streams are illuminated: fragmentation from spin-up or thermal stresses, meteoroid ejection by water vapor drag, and ejection of icy particles by CO and CO2 sublimation. The distribution of the meteoroid orbital elements probe the subsequent evolution by planetary perturbations and sample the range of dynamical processes to which Near Earth Asteroids are exposed. The non-stream "sporadic" meteors probe early stages in the evolution from meteoroid streams into the zodiacal dust cloud. We see that the lifetime of large meteoroids is generally not limited by collisions. Results obtained by the CAMS video survey of meteoroid orbits are compared to those from other orbit surveys. Since October 2010, over 200,000 meteoroid orbits have been measured. First results from an expansion into the southern hemisphere are also presented, as are first results from the measurement of main element compositions. Among the many streams detected so far, the Geminid and Sextantid showers stand out by having a relatively high particle density and derive from parent bodies that appear to have originated in the main belt.

  11. Knowledge of drug prescription in dentistry students

    Directory of Open Access Journals (Sweden)

    Guzmán-Álvarez R

    2012-06-01

    Full Text Available R Guzmán-Álvarezv,1 M Medeiros,2,3 LI Reyes Lagunes,4 AE Campos-Sepúlveda11Pharmacology Department, UNAM School of Medicine and Dentistry, Mexico City, 2Pharmacology Clinical Seminar, UNAM School of Medicine, Mexico City, 3Medical Sciences Department, Mexico Federico Gómez Children's Hospital, Mexico City, 4Measuring and Evaluation Unit, UNAM School of Psychology, Mexico City, MexicoBackground: Students in schools of dentistry attend to patients with illnesses, and often prescribe medication. Because students are still learning, they are influenced by a variety of factors: the different teaching approaches of the professors at the clinics and in the pharmacology course, fellow students, and even the information provided by the pharmaceutical industry.Objectives: The aim of this pilot study was to assess the prescription knowledge and common mistakes in fourth-year students at the School of Dentistry at the Universidad Nacional Autónoma de México.Methods: In March 2010, a survey was conducted among 66 fourth-year students at the School of Dentistry, applying a previously validated questionnaire consisting of six open-ended questions The following factors were assessed: the most frequent illness requiring dental prescription; the most prescribed nonsteroidal anti-inflammatory drugs and antibiotics; the most frequent errors; sources of information used for prescribing drugs; and whether the students knew and followed the World Health Organization Guide to Good Prescribing.Results: The most frequent response for each question was considered the most significant. The most common reason for prescribing medication was infection (n = 37, 56%, followed by pain (n = 24, 38%; the most used painkillers were ibuprofen and acetaminophen at equal levels (n = 25, 37.8%, followed by ketorolac (n = 7, 10.6%, naproxen (n = 6, 9.1%, diclofenac (n = 2, 3%, and aspirin (n = 1, 1.5%; the most widely prescribed antibiotics were amoxicillin (n = 52, 78

  12. 浙江煤山牙形石微区原位REE组成及古环境意义%In Situ Rare Earth Elements in Conodont from Meishan Section in Zhejiang Province and Implications for Paleoenvironmental Evolution

    Institute of Scientific and Technical Information of China (English)

    陈剑波; 赵来时; 陈中强; 童金南; 周炼; 胡兆初; 陈泳霖

    2012-01-01

    Trace elements and rare earth elements (REE) contents of conodonts, distinguished by very low color alteration index (CAD, were measured by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) from Meishan D section across the Permian-Triassic boundary in Zhejiang Province. Comparative analyses of surrounding rocks geochemistry study, using solutions, a significantly different response to paleo-environmental changes was revealed. Present data indicate both the total REE contents in conodont and the Ce anomalies demonstrate a more sensitive change towards temporal environmental evolution than those in whole rocks. Therefore, conodont elements are more sensitive to ambient variation than the surrounding rocks, and it is reliable for LA-ICPMS in situ analysis of conodonts. Meanwhile, we can reconstruct the Early Triassic environment using the Ce anomaly of conodont, and it provides a new evidence for acute evolutions and long-term anoxia conditions from the Permo-Triassic crisis to the Early Triassic.%本文利用激光剥蚀电感耦合等离子体质谱(LA-ICPMS),对煤山D剖面包含二叠纪—三叠纪界线层的牙形石中色变指数(CAI)较低的部分进行微区原位微量元素分析,并与利用溶解法测定的相应的沉积碳酸盐岩围岩稀土元素(REE)的组成进行了对比,探讨了它们的稀土元素组成对环境变化响应的差异及其可能的原因.结果显示,无论是稀土总量∑REE,还是Ce异常值,牙形石的微区原位REE信息比围岩更能反映出当时的环境变化.这表明牙形石化石比围岩对环境变化更加敏感,利用牙形石微区LA-ICPMS微量元素分析的方法是可靠的.同时,牙形石的Ce异常值还能对早三叠世的环境有较好的指示意义,为二叠纪与三叠纪之交大绝灭主幕开始到早三叠世环境的剧烈变化和长期缺氧环境提供了新的证据.

  13. Diagnosis-prescription studies – important steps towards a national drug prescription statistics in Norway

    Directory of Open Access Journals (Sweden)

    Jørund Straand

    2009-11-01

    Full Text Available  ABSTRACTIn the first part of this article, drug utilization and prescribing practice is discussed as seen from aNorwegian general practice perspective. Which are the data sources available? What kind of studieshave been performed? Prescription-diagnosis studies are reviewed, in particular the Møre & RomsdalPrescription Study (MRPS. Because the wholesales drug statistics do not include information aboutneither patients, prescribers or diagnoses, there is a current need for establishing a more comprehensivestatistics giving wider and deeper insights into the prescribing and utilization of drugs in the Norwegiansociety. The proposed Norwegian prescription statistics is discussed in relation to previous experiencesfrom prescription-diagnosis studies and current needs for research and statistics in the field. Someexamples are given illustrating why the 11-digit person number probably should be included in thedatabase. Lack of diagnostic information may to some extent be compensated for by introducing a moredifferentiated list of diagnoses for the drugs reimbursed. The use of data from this statistics for qualityassurance in e.g. general practice is discussed. Finally, some suggestions are given for how the Norwegianprescription statistics may be organised.

  14. Plate tectonics: Crustal recycling evolution

    Science.gov (United States)

    Magni, Valentina

    2017-09-01

    The processes that form and recycle continental crust have changed through time. Numerical models reveal an evolution from extensive recycling on early Earth as the lower crust peeled away, to limited recycling via slab break-off today.

  15. Topical Conference on the Origin of the Earth

    Science.gov (United States)

    1988-01-01

    The abstracts are presented on the topic of the origin of the Earth. The subject of planetary evolution from inner solar system plantesimals through the formation and composition of the Earth's atmosphere and the physical structure of the Earth and the Moon is explored in great variety.

  16. [Medicinal products for human use in veterinary prescription].

    Science.gov (United States)

    Kolář, Jozef; Vargová, Lucia; Ambrus, Tünde

    2015-09-01

    The paper deals with the problem of prescription and use of the medicinal products for human use in veterinary medicine. Using partial model analysis describes volume and structure of the prescription of medicinal products for human use in the veterinary practice in the years 2007-2011. Prescriptions included to the study were dispensed in a community pharmacy located in a county town in the Slovak Republic. Data were obtained from the basic collection of 845 veterinary prescriptions that included 1178 prescribed items in a total of 2954 packages.

  17. Prescription Writing Errors of Midwifery Students in Common Gynecological problems

    Directory of Open Access Journals (Sweden)

    Serveh Parang

    2014-04-01

    Full Text Available Background and aim: Giving improper prescriptions is common among medical practitioners, mostly graduates, in most communities even developed countries. So far, to our knowledge, no study has been conducted on prescription writing of graduate midwifery students. Therefore, this study aimed to detect prescription writing errors of midwifery students in common gynecological problems. Methods: In this descriptive cross-sectional study, 56 bachelor midwifery students, who had passed the theoretical and clinical courses of gynecology, were evaluated by Objective Structured Clinical Examination (OSCE. A demographic questionnaire and a standard checklist for writing the prescriptions and medications were used for data collection. SPSS Version 16 was used to carry out descriptive statistics. Findings: Most of the students were single, with the mean age of 23.0±1.7 years. Most errors were related to not recording the patients’ age and sex, diagnosis, chief complaint, and the prescriber’s name (observed in less than 10% of the prescriptions. The complete dosage schedule and drug name were stated only in 1.8±4.8 and 14±18.6 of prescriptions, respectively. In more than 93% of the cases, route of use and treatment duration were not recorded. Conclusion: According to the results, the number of prescription errors of midwifery students was high. Therefore, it is recommended to run educational courses on prescription writing skills (e.g. writing prescriptions based on World Health Organization (WHO guidelines for the midwifery students.

  18. Prescription of asthma medications before and during pregnancy in France

    DEFF Research Database (Denmark)

    Beau, Anna-Belle; Didier, Alain; Hurault-Delarue, Caroline;

    2016-01-01

    OBJECTIVE: Asthma affects between 3 to 8% of pregnant women. Previous studies have suggested that women's prescriptions for asthma medication change during pregnancy. The aim was to describe the prescription of asthma medications before and during pregnancy in France. METHODS: Women from the EFEM......OBJECTIVE: Asthma affects between 3 to 8% of pregnant women. Previous studies have suggested that women's prescriptions for asthma medication change during pregnancy. The aim was to describe the prescription of asthma medications before and during pregnancy in France. METHODS: Women from...

  19. Prescription analysis of pediatric outpatient practice in Nagpur city

    Directory of Open Access Journals (Sweden)

    Pandey Anuja

    2010-01-01

    Full Text Available Background: Medication errors are probably one of the most common types of medical errors, as medication is the most common health-care intervention. Knowing where and when errors are most likely to occur is generally felt to be the first step in trying to prevent these errors. Objective: To study prescribing patterns and errors in pediatric OPD prescriptions presenting to four community pharmacies across Nagpur city and to compare the prescription error rates across prescriber profiles. Materials and Methods: The study sample included 1376 valid pediatric OPD prescriptions presenting to four randomly selected community pharmacies in Nagpur, collected over a period of 2 months. Confirmed errors in the prescriptions were reviewed and analyzed. The core indicators for drug utilization studies, mentioned by WHO, were used to define errors. Results: The 1376 prescriptions included in the study were for a total of 3435 drugs, prescribed by 41 doctors. Fixed dose formulations dominated the prescribing pattern, many of which were irrational. Prescribing by market name was almost universal and generic prescriptions were for merely 254 (7.4% drugs. The prescribing pattern also indicated polypharmacy with the average number of drugs per encounter of 2.5. Antibiotics were included in 1087 (79% prescriptions, while injectable drugs were prescribed in 22 (1.6% prescriptions. The prescription error score varied significantly across prescriber profiles. Conclusion: The findings of our study highlight the continuing crisis of the irrational drug prescribing in the country.

  20. Mirror Prescription Regression: A Differential Interferometric Technique

    Directory of Open Access Journals (Sweden)

    Brian M. Robinson

    2010-01-01

    Full Text Available We present a remote, differential method for measuring the prescription of aspheric mirrors using null interferometry in the center-of-curvature configuration. The method requires no equipment beyond that used in a basic interferometery setup (i.e., there are no shearing elements or absolute distance meters. We chose this configuration because of its widespread use. However, the method is generalizable to other configurations with an adjustment of the governing equation. The method involves taking a series of interferograms before and after small, known misalignments are applied to the mirror in the interferometry setup and calculating the prescription (e.g., radius of curvature and conic constant of the mirror, based on these differential measurements, using a nonlinear regression. We apply this method successfully to the testing of a Space Optics Research Lab off-axis parabola with a known focal length of 152.4 mm, a diameter of 76.2 mm, and an off-axis angle of 12°.

  1. Quantitative Information on Oncology Prescription Drug Websites.

    Science.gov (United States)

    Sullivan, Helen W; Aikin, Kathryn J; Squiers, Linda B

    2016-09-02

    Our objective was to determine whether and how quantitative information about drug benefits and risks is presented to consumers and healthcare professionals on cancer-related prescription drug websites. We analyzed the content of 65 active cancer-related prescription drug websites. We assessed the inclusion and presentation of quantitative information for two audiences (consumers and healthcare professionals) and two types of information (drug benefits and risks). Websites were equally likely to present quantitative information for benefits (96.9 %) and risks (95.4 %). However, the amount of the information differed significantly: Both consumer-directed and healthcare-professional-directed webpages were more likely to have quantitative information for every benefit (consumer 38.5 %; healthcare professional 86.1 %) compared with every risk (consumer 3.1 %; healthcare professional 6.2 %). The numeric and graphic presentations also differed by audience and information type. Consumers have access to quantitative information about oncology drugs and, in particular, about the benefits of these drugs. Research has shown that using quantitative information to communicate treatment benefits and risks can increase patients' and physicians' understanding and can aid in treatment decision-making, although some numeric and graphic formats are more useful than others.

  2. Diabetic nephropathy: Prescription trends in tertiary care

    Directory of Open Access Journals (Sweden)

    Devi D

    2008-01-01

    Full Text Available Diabetic nephropathy is a leading cause of end stage renal disease. Drug utilization studies could promote rational drug use. The objective of this study was to evaluate prescribing trends in hospitalized patients with diabetic nephropathy. A prospective, observational study was conducted in a tertiary care hospital. The demographic, disease and treatment data of patients with diabetic nephropathy were collected for a period of six months and analysed. Drugs were classified using World Health Organization recommended Anatomic Therapeutic Chemical classification. A total of 755 drugs (7.4 drugs per prescription were prescribed to 102 study patients, who were all hypertensive and in late stages of diabetic nephropathy. Drug classes with largest representation were those acting on gastrointestinal tract plus metabolism (37% and cardiovascular drugs (28%. Calcium channel blockers represented the largest antihypertensive drug class (41%. Almost three-fourths of patients received more than one antihypertensive agent. Approximately 37% of patients did not receive any antidiabetic medication. Of those who did, prescriptions for insulin (91% exceeded those of oral hypoglycaemic drugs (9%. Antimicrobials accounted for 10.2% of all drugs prescribed, of which 31.8% were quinolones. Drugs prescribed by generic name accounted for 11.98%. While all patients received antihypertensive therapy, more than a third were not on any antidiabetic treatment. Antihypertensive poly-therapy was observed in the majority with calcium channel blockers being most frequently prescribed antihypertensive drug class. Insulin was the preferred to hypoglycaemic drugs.

  3. The NAL-NL2 prescription procedure

    Directory of Open Access Journals (Sweden)

    G. Keidser

    2011-03-01

    Full Text Available NAL-NL2 is the second generation of prescription procedures from The National Acoustic Laboratories (NAL for fitting wide dynamic range compression (WDRC instruments. Like its predecessor NALNL1 (Dillon, 1999, NAL-NL2 aims at making speech intelligible and overall loudness comfortable. This aim is mainly driven by a belief that these factors are most important for hearing aid users, but is also driven by the fact that less information is available about how to adjust gain to optimise other parameters that affect prescription such as localisation, tonal quality, detection of environmental sounds, and naturalness. In both formulas, the objective is achieved by combining a speech intelligibility model and a loudness model in an adaptive computer- controlled optimisation process. Adjustments have further been made to the theoretical component of NAL-NL2 that are directed by empirical data collected during the past decade with NAL-NL1. In this paper, the data underlying NAL-NL2 and the derivation procedure are presented, and the main differences from NAL-NL1 are outlined.

  4. How prescriptive norms influence causal inferences.

    Science.gov (United States)

    Samland, Jana; Waldmann, Michael R

    2016-11-01

    Recent experimental findings suggest that prescriptive norms influence causal inferences. The cognitive mechanism underlying this finding is still under debate. We compare three competing theories: The culpable control model of blame argues that reasoners tend to exaggerate the causal influence of norm-violating agents, which should lead to relatively higher causal strength estimates for these agents. By contrast, the counterfactual reasoning account of causal selection assumes that norms do not alter the representation of the causal model, but rather later causal selection stages. According to this view, reasoners tend to preferentially consider counterfactual states of abnormal rather than normal factors, which leads to the choice of the abnormal factor in a causal selection task. A third view, the accountability hypothesis, claims that the effects of prescriptive norms are generated by the ambiguity of the causal test question. Asking whether an agent is a cause can be understood as a request to assess her causal contribution but also her moral accountability. According to this theory norm effects on causal selection are mediated by accountability judgments that are not only sensitive to the abnormality of behavior but also to mitigating factors, such as intentionality and knowledge of norms. Five experiments are presented that favor the accountability account over the two alternative theories.

  5. Accretion and early evolution of Earth

    DEFF Research Database (Denmark)

    Saji, Nikitha Susan

    -stage impacts had to play in determining the bulk composition as well as pace of the chemical dierentiation and internal dynamics of terrestrial planets - is preserved in the form of isotopic signatures in some of the oldest terrestrial and extraterrestrial samples available to us. A potential means to unravel...... this is by the application of Nd-isotope systematics as the coupled 146;147Sm - 143;142Nd decay system enables the study of chronology of planetary silicate mantles while the stable Nd-isotopes help track the origin and early transport of material. Deciphering this information, however, requires the analytical capability...... in solar system materials is found to be related to selective thermal processing of dust in the early nebula given the correlation observed for these eects with Fe-peak neutron-rich isotope anomalies, whose origin is attributed to distinct nucleosnythetic sites other than classical s-, r- or p...

  6. Alcohol and prescription drug safety in older adults

    Directory of Open Access Journals (Sweden)

    Zanjani F

    2013-02-01

    Full Text Available Faika Zanjani,1,2 Aasha I Hoogland,1 Brian G Downer11Department of Gerontology, 2Building Interdisciplinary Research Careers in Women's Health University of Kentucky, Lexington, KY, USABackground: The objectives of this study were to investigate older adults' knowledge of prescription drug safety and interactions with alcohol, and to identify pharmacists' willingness to disseminate prescription drug safety information to older adults.Methods: The convenience sample consisted of 48 older adults aged 54–89 years who were recruited from a local pharmacy and who completed surveys addressing their alcohol consumption, understanding of alcohol and prescription drug interactions, and willingness to change habits regarding alcohol consumption and prescription drugs. To address pharmacist willingness, 90 pharmacists from local pharmacies volunteered and answered questions regarding their willingness to convey prescription drug safety information to older adults.Results: Older adults reported low knowledge of alcohol and prescription drug safety, with women tending to be slightly more knowledgeable. More importantly, those who drank in the previous few months were less willing to talk to family and friends about how alcohol can have harmful interactions with prescription drugs, or to be an advocate for safe alcohol and prescription drug use than those who had not had a drink recently. Pharmacists reported that they were willing to convey prescription drug safety information to older adults via a variety of formats, including displaying or distributing a flyer, and directly administering a brief intervention.Conclusion: In this study, older adults were found to have inadequate knowledge of prescription drug safety and interactions with alcohol, but pharmacists who regularly come in contact with older adults indicated that they were ready and willing to talk to older adults about prescription drug safety. Future research should focus on interventions

  7. Prescription writing trends of antihistamines at the university health centre.

    Science.gov (United States)

    Kumar, Anil; Beenta

    2009-05-01

    The aim of the present study was to establish antihistamines drug prescribing pattern in order to improve the rational prescribing of antihistamines by physicians at Panjab University Health Centre. The study was performed in between the months of November 2005 to April 2006. Five hundred out patients were monitored and data was collected on WHO-based prescription-auditing performa. Demographic analysis of this prospective study revealed that out of the 500 patients, 293 (58.6 %) were male and 207 (41.4 %) were female and maximum patients were in the age group of 21-40 (34.8 %). Chlorpheniramine maleate (235 prescriptions) was the highest prescribed among antihistamine prescriptions (36.89 %) followed by diphenhydramine hydrochloride (186 prescriptions, 29.19%), cetirizine (175 prescriptions, 27.47 %) and promethazine (41 prescriptions, 6.4%). In comparison to generic drugs (169 prescriptions, 26.54%), branded were more prescribed at PUHC. Majority of antihistamines were in form of tablets (414 prescriptions, 64.99%) followed by liquid formulations (195 prescriptions, 30.61%) and injections (28 prescriptions, 4.40%). The average cost of different antihistamine drugs prescribed was as follows: diphenhydramine hydrochloride Rs. 34.74 followed by promethzine Rs. 22.46, chlorpheniramine maleate Rs. 15.30, and cetirizine Rs. 13.50. Average numbers of drugs prescribed per prescription were 1.27. The average consulting and dispensing time was 4.82 and 3.56 min, respectively. Out of the 500 university patients, 258 (51.6%) had the knowledge regarding the medication prescribed and 242 (48.4%) were unaware of the medication prescribed.

  8. Prescription writing trends of antihistamines at the university health centre

    Directory of Open Access Journals (Sweden)

    Kumar Anil

    2009-01-01

    Full Text Available The aim of the present study was to establish antihistamines drug prescribing pattern in order to improve the rational prescribing of antihistamines by physicians at Panjab University Health Centre. The study was performed in between the months of November 2005 to April 2006. Five hundred out patients were monitored and data was collected on WHO-based prescription-auditing performa. Demographic analysis of this prospective study revealed that out of the 500 patients, 293 (58.6 % were male and 207 (41.4 % were female and maximum patients were in the age group of 21-40 (34.8 %. Chlorpheniramine maleate (235 prescriptions was the highest prescribed among antihistamine prescriptions (36.89 % followed by diphenhydramine hydrochloride (186 prescriptions, 29.19%, cetirizine (175 prescriptions, 27.47 % and promethazine (41 prescriptions, 6.4%. In comparison to generic drugs (169 prescriptions, 26.54%, branded were more prescribed at PUHC. Majority of antihistamines were in form of tablets (414 prescriptions, 64.99% followed by liquid formulations (195 prescriptions, 30.61% and injections (28 prescriptions, 4.40%. The average cost of different antihistamine drugs prescribed was as follows: diphenhydramine hydrochloride Rs. 34.74 followed by promethzine Rs. 22.46, chlorpheniramine maleate Rs. 15.30, and cetirizine Rs. 13.50. Average numbers of drugs prescribed per prescription were 1.27. The average consulting and dispensing time was 4.82 and 3.56 min, respectively. Out of the 500 university patients, 258 (51.6% had the knowledge regarding the medication prescribed and 242 (48.4% were unaware of the medication prescribed.

  9. Sulfur Earth

    Science.gov (United States)

    de Jong, B. H.

    2007-12-01

    Variations in surface tension affect the buoyancy of objects floating in a liquid. Thus an object floating in water will sink deeper in the presence of dishwater fluid. This is a very minor but measurable effect. It causes for instance ducks to drown in aqueous solutions with added surfactant. The surface tension of liquid iron is very strongly affected by the presence of sulfur which acts as a surfactant in this system varying between 1.9 and 0.4 N/m at 10 mass percent Sulfur (Lee & Morita (2002), This last value is inferred to be the maximum value for Sulfur inferred to be present in the liquid outer core. Venting of Sulfur from the liquid core manifests itself on the Earth surface by the 105 to 106 ton of sulfur vented into the atmosphere annually (Wedepohl, 1984). Inspection of surface Sulfur emission indicates that venting is non-homogeneously distributed over the Earth's surface. The implication of such large variation in surface tension in the liquid outer core are that at locally low Sulfur concentration, the liquid outer core does not wet the predominantly MgSiO3 matrix with which it is in contact. However at a local high in Sulfur, the liquid outer core wets this matrix which in the fluid state has a surface tension of 0.4 N/m (Bansal & Doremus, 1986), couples with it, and causes it to sink. This differential and diapiric movement is transmitted through the essentially brittle mantle (1024 Pa.s, Lambeck & Johnson, 1998; the maximum value for ice being about 1030 Pa.s at 0 K, in all likely hood representing an upper bound of viscosity for all materials) and manifests itself on the surface by the roughly 20 km differentiation, about 0.1 % of the total mantle thickness, between topographical heights and lows with concomitant lateral movement in the crust and upper mantle resulting in thin skin tectonics. The brittle nature of the medium though which this movement is transmitted suggests that the extremes in topography of the D" layer are similar in range to

  10. 21 CFR 1306.06 - Persons entitled to fill prescriptions.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Persons entitled to fill prescriptions. 1306.06 Section 1306.06 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE PRESCRIPTIONS... either registered individually or employed in a registered pharmacy, a registered central fill pharmacy...

  11. 21 CFR 1306.22 - Refilling of prescriptions.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Refilling of prescriptions. 1306.22 Section 1306.22 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE PRESCRIPTIONS Controlled... pharmacy for a period of two years from the dispensing date. This printout of the day's controlled...

  12. Pharmaceutical interventions on prescription problems in a Danish pharmacy setting

    DEFF Research Database (Denmark)

    Pottegård, Anton; Hallas, Jesper; Søndergaard, Jens

    2011-01-01

    International studies regarding pharmacists' interventions towards prescription problems produce highly variable results. The only peer-reviewed study in a Danish setting estimated an intervention rate of 2.3 per 1,000 prescriptions. With the introduction of a new tool for registration, we hypoth...

  13. Relationship between e-prescriptions and community pharmacy workflow.

    Science.gov (United States)

    Odukoya, Olufunmilola K; Chui, Michelle A

    2012-01-01

    To understand how community pharmacists use electronic prescribing (e-prescribing) technology and to describe the workflow challenges pharmacy personnel encounter as a result of using e-prescribing technology. Cross-sectional qualitative study. Seven community pharmacies in Wisconsin from December 2010 to March 2011. 16 pharmacists and 14 pharmacy technicians (in three chain and four independent pharmacies). Think-aloud protocols and pharmacy group interviews. Pharmacy staff descriptions of their use of e-prescribing technology and challenges encountered in their daily workflow related to this technology. Two contributing factors were perceived to influence e-prescribing workflow: issues stemming from prescribing or transmitting software and issues from within the pharmacy. Pharmacies experienced both delayed and inaccurate e-prescriptions from physician offices. An overwhelming number of e-prescriptions with inaccurate or unclear information resulted in serious time delays for patients as pharmacists contacted physicians to clarify wrong information. In addition, lack of formal training and the disconnect between pharmacy procedures for verifying prescription accuracy and presentation of e-prescription information on the computer screen influenced the speed of processing an e-prescription. E-prescriptions processing can hinder pharmacy workflow. As the number of e-prescriptions transmitted to pharmacies increases because of legislative mandates, it is essential that the technology supporting e-prescriptions (both on the prescriber and pharmacy operating systems) be redesigned to facilitate pharmacy workflow processes and to prevent unintended increase in medication errors, user frustration, and stress.

  14. Prescriptive Profile Procedure for Children With Learning Disabilities.

    Science.gov (United States)

    Levine, Eleanor; Fineman, Carol

    The Prescriptive Profile Procedure (PPP) attempts to provide teachers of learning disabled elementary school children with a procedure of individualized diagnosis and educational prescription which encompasses strengths and weaknesses in prerequisite skills, basic school subjects, and behavioral factors. A competency statement and six to 12…

  15. Asthma prescription patterns for children: can GPs do better?

    NARCIS (Netherlands)

    Uijen, J.H.J.M.; Wouden, J.C. van der; Schellevis, F.G.; Willemsen, S.P.; Suijlekom-Smit, L.W.A. van; Bindels, P.J.E.

    2011-01-01

    Background: Assessing prescription patterns of asthma medication for children is helpful to optimize prescribing by general practitioners (GPs). The aim was to explore prescription patterns in children with physician-diagnosed asthma and its determinants in general practice. Methods: We used the Sec

  16. Prescription Drug Abuse Information in D.A.R.E.

    Science.gov (United States)

    Morris, Melissa C.; Cline, Rebecca J. Welch; Weiler, Robert M.; Broadway, S. Camille

    2006-01-01

    This investigation was designed to examine prescription drug-related content and learning objectives in Drug Abuse Resistance Education (D.A.R.E.) for upper elementary and middle schools. Specific prescription-drug topics and context associated with content and objectives were coded. The coding system for topics included 126 topics organized…

  17. [Failure mode and effects analysis on computerized drug prescriptions].

    Science.gov (United States)

    Paredes-Atenciano, J A; Roldán-Aviña, J P; González-García, Mercedes; Blanco-Sánchez, M C; Pinto-Melero, M A; Pérez-Ramírez, C; Calvo Rubio-Burgos, Miguel; Osuna-Navarro, F J; Jurado-Carmona, A M

    2015-01-01

    To identify and analyze errors in drug prescriptions of patients treated in a "high resolution" hospital by applying a Failure mode and effects analysis (FMEA).Material and methods A multidisciplinary group of medical specialties and nursing analyzed medical records where drug prescriptions were held in free text format. An FMEA was developed in which the risk priority index (RPI) was obtained from a cross-sectional observational study using an audit of the medical records, carried out in 2 phases: 1) Pre-intervention testing, and (2) evaluation of improvement actions after the first analysis. An audit sample size of 679 medical records from a total of 2,096 patients was calculated using stratified sampling and random selection of clinical events. Prescription errors decreased by 22.2% in the second phase. FMEA showed a greater RPI in "unspecified route of administration" and "dosage unspecified", with no significant decreases observed in the second phase, although it did detect, "incorrect dosing time", "contraindication due to drug allergy", "wrong patient" or "duplicate prescription", which resulted in the improvement of prescriptions. Drug prescription errors have been identified and analyzed by FMEA methodology, improving the clinical safety of these prescriptions. This tool allows updates of electronic prescribing to be monitored. To avoid such errors would require the mandatory completion of all sections of a prescription. Copyright © 2014 SECA. Published by Elsevier Espana. All rights reserved.

  18. Prosthetic prescription in the Netherlands: An observational study

    NARCIS (Netherlands)

    Van Der Linde, H.; Geertzen, J.H.B.; Hofstad, C.J.; Van Limbeek, J.; Postema, K.

    2003-01-01

    Prosthetic prescription for lower limb amputees and the methodology used are primarily based on empirical knowledge. Clinical expertise plays an important role that can lead to an adequate prescription; however, a clear evidence based motivation for the choices made cannot be given. This can lead to

  19. Pattern of prescription drug use in Nigerian army hospitals

    African Journals Online (AJOL)

    To our knowledge, only few studies have been done in Africa on this issue , with inadequate ... high number of drugs per prescription, high rate of antibiotic usage and unscientific prescription by doctors. ..... the managers of Nigerian public health institutions through the ... use promotes drug resistance, increases risk of side.

  20. Preventing Prescription Drug Abuse in Adolescence: A Collaborative Approach

    Science.gov (United States)

    Jones, Beth A.; Fullwood, Harry; Hawthorn, Melissa

    2012-01-01

    With the growing awareness of adolescent prescription drug abuse, communities and schools are beginning to explore prevention and intervention strategies which are appropriate for their youth. This article provides a framework for developing a collaborative approach to prescription drug abuse prevention--called the Prevention Awareness Team--that…

  1. Asthma prescription patterns for children: can GPs do better?

    NARCIS (Netherlands)

    Uijen, J.H.J.M.; Wouden, J.C. van der; Schellevis, F.G.; Willemsen, S.P.; Suijlekom-Smit, L.W.A. van; Bindels, P.J.E.

    2011-01-01

    Background: Assessing prescription patterns of asthma medication for children is helpful to optimize prescribing by general practitioners (GPs). The aim was to explore prescription patterns in children with physician-diagnosed asthma and its determinants in general practice. Methods: We used the

  2. 21 CFR 202.1 - Prescription-drug advertisements.

    Science.gov (United States)

    2010-04-01

    ...) DRUGS: GENERAL PRESCRIPTION DRUG ADVERTISING § 202.1 Prescription-drug advertisements. (e) * * * (6... drug, nor may an advertisement contain a quantitative statement of safety or effectiveness (a) unless... effectiveness is supported by substantial evidence derived from adequate and well-controlled studies as defined...

  3. Overview of Four Prescription Monitoring/Review Programs in Canada

    Directory of Open Access Journals (Sweden)

    Andrea D Furlan

    2014-01-01

    Full Text Available BACKGROUND: Prescription monitoring or review programs collect information about prescription and dispensing of controlled substances for the purposes of monitoring, analysis and education. In Canada, it is the responsibility of the provincial institutions to organize, maintain and run such programs.

  4. Recognizing Signs of Prescription Drug Abuse and Addiction, Part I.

    Science.gov (United States)

    Felicilda-Reynaldo, Faye D

    2014-01-01

    Prescription drug abuse/misuse is increasing. Nonmedical use of prescription medications, especially opioid analgesics, now is considered an epidemic in the United States. Medical-surgical nurses are in a strategic position to help address substance abuse problems in patients.

  5. EXERCISE ON PRESCRIPTION AUDIT : A TOOL FOR PHARMACOLOGY PRACTICAL LESSON

    Directory of Open Access Journals (Sweden)

    Supreeti Biswas

    2012-07-01

    Full Text Available To improve the understanding and perception about rational prescribing among the Undergraduate (UG students, a record based study 'exercise on prescription audit' was undertaken as self-directed learning strategy. Study was conducted on Objectively Structured Evaluation of pharmacotherapy taking one year record of prescriptions in Bed Head Tickets (BHTs of discharged Ophthalmic in-patients. Standard format for prescription writing, WHO guide to Good prescribing and Essential Medicines were followed to assess the in-patient prescriptions. Students improved markedly (p< 0.001 in audit of real prescriptions. Results revealed that 37 types of drugs were prescribed over 948 BHTs. Completeness of the prescription showed 100% perfection in maximum indicators with exception in judicious investigations (99.89%, medication information (89.32% and relevant advices for patient (97.12%. Subsidiary or symptomatic drugs (56.76% were prescribed more than the core drugs (43.24% of total drugs prescribed. Generic prescription was 54.05%. Study in turn improved the understanding and perception about rational prescribing among the students. The students gained knowledge about the utilization of different types of dosage forms of drugs. Prescription audit as self-directed learning must be a tool for practical lesson of Pharmacology for UG-course as well as for PG-curriculum.

  6. Nonmedical Prescription Drug Use among Midwestern Rural Adolescents

    Science.gov (United States)

    Park, Nicholas K.; Melander, Lisa; Sanchez, Shanell

    2016-01-01

    Prescription drug misuse has been an increasing problem in the United States, yet few studies have examined the protective factors that reduce risk of prescription drug abuse among rural adolescents. Using social control theory as a theoretical framework, we test whether parent, school, and community attachment reduce the likelihood of lifetime…

  7. 77 FR 8174 - EPAAR Prescription for Work Assignments

    Science.gov (United States)

    2012-02-14

    ... revised language communicates to contract personnel and program staff that government cost-related... (EPA). ACTION: Final rule. SUMMARY: EPA will amend the EPA Acquisition Regulation (EPAAR) prescription for the work assignment clause. This final rule provides revised language to the prescription for the...

  8. 76 FR 26232 - EPAAR Prescription for Work Assignments

    Science.gov (United States)

    2011-05-06

    ... Acquisition Regulation (EPAAR) to update policy, procedures, and contract clauses. The proposed rule provides revised language to the prescription for the work assignment clause, incorporating prescriptive language that provides further instructions on use of the related clause. DATES: Comments must be received on or...

  9. Do Physicians Change Prescription Practice in Response to Financial Incentives?

    Science.gov (United States)

    Park, Sylvia; Han, Euna

    2016-07-01

    We assessed the impact on physician prescription behaviors of an outpatient prescription incentive program providing financial rewards to primary care physicians for saving prescription costs in South Korea. A 10% sample of clinics (N = 1,625) was randomly selected from all clinics in the National Health Insurance claims database for the years 2009-2012, and all claims with the primary diagnosis of peptic ulcer or gastro-esophageal reflux diseases were extracted from those clinics' data. A clinic-level random-effects model was used. After the program, clinics in general medicine showed a lower prescription rate (by 0.8 percentage points), lower number of medicines prescribed (by 0.02), lower prescription duration (by 0.15 days), and lower drug expenditure per claim (by 740 won). Small clinics on the <25th percentile of a regional sum of monthly drug expenditure had shorter prescription duration (by 0.76 days), while large clinics on the ≥75th percentile and clinics in group practice had a higher prescription rate (by 1.5 and 2.5 percentage points, respectively) and a higher number of medicines prescribed (by 0.03 for group practice only) after the program. The outpatient prescription incentive program worked as intended only in certain subgroup clinics for the target medicines.

  10. Controversy in Purchasing Prescription Drugs Online in China.

    Science.gov (United States)

    Yuan, Peng; Qi, Lin; Wang, Long

    2016-08-01

    China's government is considering legalization of online prescription drugs to increase the pharmaceutical market and enhance access to necessary medicines. However, challenges such as a shortage of licensed pharmacists and drug quality issues have raised concerns and delayed consensus on the proposal. China's government must address the most pressing issues so it can render a decision on online prescription sales.

  11. 77 FR 20637 - Request for Information on Prescription Medication Adherence

    Science.gov (United States)

    2012-04-05

    ... HUMAN SERVICES Request for Information on Prescription Medication Adherence AGENCY: Department of Health... potential solutions associated with the public health problem of prescription medication non-adherence in..., health care providers, and industry and private organizations in efforts to improve medication...

  12. Prosthetic prescription in the Netherlands : an observational study

    NARCIS (Netherlands)

    van der Linde, H; Geertzen, JHB; Hofstad, CJ; Postema, K

    2003-01-01

    Prosthetic prescription for lower limb amputees and the methodology used are primarily based on empirical knowledge. Clinical expertise plays an important role that can lead to an adequate prescription; however, a clear evidence based motivation for the choices made cannot be given. This can lead to

  13. Phenomenological implementations of TMD evolution

    Energy Technology Data Exchange (ETDEWEB)

    Boglione, Mariaelena [University of Turin, Torino, Italy; Gonzalez Hernandez, Jose Osvaldo [University of Virginia, Charlottesville, VA; Melis, Stefano [European Centre for Theoretical Studies; Prokudin, Alexey [JLAB

    2015-03-01

    Although the theoretical set-up of TMD evolution appears to be well established, its phenomenological implementations still require special attention, particularly as far as the interplay between perturbative and non-perturbative contributions is concerned. These issues have been extensively studied in Drell-Yan processes, where they seem to be reasonably under control. Instead, applying the same prescriptions and methodologies to Semi-Inclusive Deep Inelastic (SIDIS) processes is, at present, far from obvious. Some of the controversies related to the applications of TMD Evolution to SIDIS processes will be discussed with practical examples, exploring different kinematical configurations of SIDIS experiments.

  14. Phenomenological implementations of TMD evolution

    CERN Document Server

    Boglione, M; Melis, S; Prokudin, A

    2014-01-01

    Although the theoretical set-up of TMD evolution appears to be well established, its phenomenological implementations still require special attention, particularly as far as the interplay between perturbative and non-perturbative contributions is concerned. These issues have been extensively studied in Drell-Yan processes, where they seem to be reasonably under control. Instead, applying the same prescriptions and methodologies to Semi-Inclusive Deep Inelastic (SIDIS) processes is, at present, far from obvious. Some of the controversies related to the applications of TMD Evolution to SIDIS processes will be discussed with practical examples, exploring different kinematical configurations of SIDIS experiments.

  15. Revolutions that made the earth

    CERN Document Server

    Lenton, Tim

    2013-01-01

    The Earth that sustains us today was born out of a few remarkable, near-catastrophic revolutions, started by biological innovations and marked by global environmental consequences. The revolutions have certain features in common, such as an increase in the complexity, energy utilization, and information processing capabilities of life. This book describes these revolutions, showing the fundamental interdependence of the evolution of life and its non-living environment. We would not exist unless these upheavals had led eventually to 'successful' outcomes - meaning that after each one, at length, a new stable world emerged. The current planet-reshaping activities of our species may be the start of another great Earth system revolution, but there is no guarantee that this one will be successful. This book explains what a successful transition through it might look like, if we are wise enough to steer such a course. This book places humanity in context as part of the Earth system, using a new scientific synthe...

  16. Models of the earth's core

    Science.gov (United States)

    Stevenson, D. J.

    1981-01-01

    Combined inferences from seismology, high-pressure experiment and theory, geomagnetism, fluid dynamics, and current views of terrestrial planetary evolution lead to models of the earth's core with five basic properties. These are that core formation was contemporaneous with earth accretion; the core is not in chemical equilibrium with the mantle; the outer core is a fluid iron alloy containing significant quantities of lighter elements and is probably almost adiabatic and compositionally uniform; the more iron-rich inner solid core is a consequence of partial freezing of the outer core, and the energy release from this process sustains the earth's magnetic field; and the thermodynamic properties of the core are well constrained by the application of liquid-state theory to seismic and labroatory data.

  17. Optimal Measures for Characterizing Water-rich Super-Earths

    CERN Document Server

    Madhusudhan, Nikku

    2014-01-01

    The detection and atmospheric characterization of super-Earths is one of the major frontiers of exoplanetary science. Currently, extensive efforts are underway to detect molecules, particularly H2O, in super-Earth atmospheres. In the present work, we develop a systematic set of strategies to identify and observe potentially H2O-rich super-Earths that provide the best prospects for characterizing their atmospheres using existing instruments. Firstly, we provide analytic prescriptions and discuss factors that need to be taken into account while planning and interpreting observations of super-Earth radii and spectra. We discuss how observations in different spectral bandpasses constrain different atmospheric properties of a super-Earth, including radius and temperature of the planetary surface as well as the mean molecular mass, the chemical composition and thermal profile of the atmosphere. In particular, we caution that radii measured in certain bandpasses can induce biases in the interpretation of the interio...

  18. Prescription Drug Monitoring Programs and Other Interventions to Combat Prescription Opioid Abuse

    Directory of Open Access Journals (Sweden)

    Bharath Chakravarthy

    2012-12-01

    Full Text Available The Center for Disease Control and Prevention (CDC has published significant data and trendsrelated to opioid prescription pain relievers (OPR. In 2008, 20,044 deaths were attributedto prescription drug overdose of which 14,800 (73.8% were due to OPR, an amount greaterthan the number of overdose deaths from heroin and cocaine combined. The majority of thesedeaths were unintentional. Between 1999-2008, overdose deaths from OPR increased almostfour-fold. Correspondingly, sales of OPR were four times greater in 2010 than in 1999. Mostsignificant to emergency physicians is the estimate that 39% of all opioids prescribed, administeredor continued come from the emergency department (ED. We present findings from theCDC’s Morbidity and Mortality Weekly Report (MMWR with commentary on current recommendationsand policies for curtailing the OPR epidemic.1

  19. The appropriateness of a proton pump inhibitor prescription.

    LENUS (Irish Health Repository)

    Moran, N

    2014-11-01

    Proton pump inhibitors (PPIs) are one of the most commonly prescribed groups of drug in Ireland, at great expense to the Irish healthcare executive. This study aims to evaluate the appropriateness of PPI prescriptions on admission and discharge in a tertiary referral hospital. All non-elective admissions in the Emergency Department in one week were included in the study. 102 patients in total were included, with 36 (35.4%) treated with a PPI on admission. Of these, only 3 (8.3%) had a clear indication noted as per current NICE guidelines. 18 new in-hospital PPI prescriptions were documented. 11 (61%) of which were present on discharge prescriptions. Continuing PPI prescription on discharge into the community may be inappropriate, costly and potentially harmful. Brief interventions aimed at reducing inappropriate PPI prescriptions have been shown to be effective at reducing the cost and potential harm of unnecessary treatment.

  20. Delayed antibiotic prescriptions for respiratory infections.

    Science.gov (United States)

    Spurling, Geoffrey Kp; Del Mar, Chris B; Dooley, Liz; Foxlee, Ruth; Farley, Rebecca

    2017-09-07

    Concerns exist regarding antibiotic prescribing for respiratory tract infections (RTIs) owing to adverse reactions, cost, and antibacterial resistance. One proposed strategy to reduce antibiotic prescribing is to provide prescriptions, but to advise delay in antibiotic use with the expectation that symptoms will resolve first. This is an update of a Cochrane Review originally published in 2007, and updated in 2010 and 2013. To evaluate the effects on clinical outcomes, antibiotic use, antibiotic resistance, and patient satisfaction of advising a delayed prescription of antibiotics in respiratory tract infections. For this 2017 update we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, Issue 4, 2017), which includes the Cochrane Acute Respiratory Infection Group's Specialised Register; Ovid MEDLINE (2013 to 25 May 2017); Ovid Embase (2013 to 2017 Week 21); EBSCO CINAHL Plus (1984 to 25 May 2017); Web of Science (2013 to 25 May 2017); WHO International Clinical Trials Registry Platform (1 September 2017); and ClinicalTrials.gov (1 September 2017). Randomised controlled trials involving participants of all ages defined as having an RTI, where delayed antibiotics were compared to immediate antibiotics or no antibiotics. We defined a delayed antibiotic as advice to delay the filling of an antibiotic prescription by at least 48 hours. We considered all RTIs regardless of whether antibiotics were recommended or not. We used standard Cochrane methodological procedures. Three review authors independently extracted and collated data. We assessed the risk of bias of all included trials. We contacted trial authors to obtain missing information. For this 2017 update we added one new trial involving 405 participants with uncomplicated acute respiratory infection. Overall, this review included 11 studies with a total of 3555 participants. These 11 studies involved acute respiratory infections including acute otitis media (three studies

  1. Earth Abides Arsenic Biotransformations

    Science.gov (United States)

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2014-05-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.

  2. Earth Abides Arsenic Biotransformations

    Science.gov (United States)

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2015-01-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice. PMID:26778863

  3. How do community pharmacies recover from e-prescription errors?

    Science.gov (United States)

    Odukoya, Olufunmilola K; Stone, Jamie A; Chui, Michelle A

    2014-01-01

    The use of e-prescribing is increasing annually, with over 788 million e-prescriptions received in US pharmacies in 2012. Approximately 9% of e-prescriptions have medication errors. To describe the process used by community pharmacy staff to detect, explain, and correct e-prescription errors. The error recovery conceptual framework was employed for data collection and analysis. 13 pharmacists and 14 technicians from five community pharmacies in Wisconsin participated in the study. A combination of data collection methods were utilized, including direct observations, interviews, and focus groups. The transcription and content analysis of recordings were guided by the three-step error recovery model. Most of the e-prescription errors were detected during the entering of information into the pharmacy system. These errors were detected by both pharmacists and technicians using a variety of strategies which included: (1) performing double checks of e-prescription information; (2) printing the e-prescription to paper and confirming the information on the computer screen with information from the paper printout; and (3) using colored pens to highlight important information. Strategies used for explaining errors included: (1) careful review of patient's medication history; (2) pharmacist consultation with patients; (3) consultation with another pharmacy team member; and (4) use of online resources. In order to correct e-prescription errors, participants made educated guesses of the prescriber's intent or contacted the prescriber via telephone or fax. When e-prescription errors were encountered in the community pharmacies, the primary goal of participants was to get the order right for patients by verifying the prescriber's intent. Pharmacists and technicians play an important role in preventing e-prescription errors through the detection of errors and the verification of prescribers' intent. Future studies are needed to examine factors that facilitate or hinder recovery

  4. How do Community Pharmacies Recover from E-prescription Errors?

    Science.gov (United States)

    Odukoya, Olufunmilola K.; Stone, Jamie A.; Chui, Michelle A.

    2014-01-01

    Background The use of e-prescribing is increasing annually, with over 788 million e-prescriptions received in US pharmacies in 2012. Approximately 9% of e-prescriptions have medication errors. Objective To describe the process used by community pharmacy staff to detect, explain, and correct e-prescription errors. Methods The error recovery conceptual framework was employed for data collection and analysis. 13 pharmacists and 14 technicians from five community pharmacies in Wisconsin participated in the study. A combination of data collection methods were utilized, including direct observations, interviews, and focus groups. The transcription and content analysis of recordings were guided by the three-step error recovery model. Results Most of the e-prescription errors were detected during the entering of information into the pharmacy system. These errors were detected by both pharmacists and technicians using a variety of strategies which included: (1) performing double checks of e-prescription information; (2) printing the e-prescription to paper and confirming the information on the computer screen with information from the paper printout; and (3) using colored pens to highlight important information. Strategies used for explaining errors included: (1) careful review of patient’ medication history; (2) pharmacist consultation with patients; (3) consultation with another pharmacy team member; and (4) use of online resources. In order to correct e-prescription errors, participants made educated guesses of the prescriber’s intent or contacted the prescriber via telephone or fax. When e-prescription errors were encountered in the community pharmacies, the primary goal of participants was to get the order right for patients by verifying the prescriber’s intent. Conclusion Pharmacists and technicians play an important role in preventing e-prescription errors through the detection of errors and the verification of prescribers’ intent. Future studies are needed

  5. Introducing Earth Sciences Students to Modeling Using MATLAB Exercises

    Science.gov (United States)

    Anderson, R. S.

    2003-12-01

    While we subject our students to math and physics and chemistry courses to complement their geological studies, we rarely allow them to experience the joys of modeling earth systems. Given the degree to which modern earth sciences relies upon models of complex systems, it seems appropriate to allow our students to develop some experience with this activity. In addition, as modeling is an unforgivingly logical exercise, it demands the student absorb the fundamental concepts, the assumptions behind them, and the means of constraining the relevant parameters in a problem. These concepts commonly include conservation of some quantity, the fluxes of that quantity, and careful prescription of the boundary and initial conditions. I have used MATLAB as an entrance to this world, and will illustrate the products of the exercises we have worked. This software is platform-independent, and has a wonderful graphics package (including movies) that is embedded intimately as one-to-several line calls. The exercises should follow a progression from simple to complex, and serve to introduce the many discrete tasks within modeling. I advocate full immersion in the first exercise. Example exercises include: growth of spatter cones (summation of parabolic trajectories of lava bombs); response of thermal profiles in the earth to varying surface temperature (thermal conduction); hillslope or fault scarp evolution (topographic diffusion); growth and subsidence of volcanoes (flexure); and coral growth on a subsiding platform in the face of sealevel fluctuations (coral biology and light extinction). These exercises can be motivated by reading a piece in the classical or modern literature that either describes a model, or better yet serves to describe the system well, but does not present a model. I have found that the generation of movies from even the early simulation exercises serves as an additional motivator for students. We discuss the models in each class meeting, and learn that there

  6. Identification and management of prescription drug abuse in pregnancy.

    Science.gov (United States)

    Worley, Julie

    2014-01-01

    Prescription drug abuse is a growing problem in the United States and many other countries. Estimates of prescription drug abuse rates during pregnancy range from 5% to 20%. The primary prescription drugs designated as controlled drugs with abuse potential in pregnancy are opiates prescribed for pain, benzodiazepines prescribed for anxiety, and stimulants prescribed for attention-deficit/hyperactivity disorder. Prescription drugs are obtained for abuse through diversion methods, such as purchasing them from others or by doctor shopping. The use of prescription drugs puts both the mother and the fetus at high risk during pregnancy. Identification of women who are abusing prescription drugs is important so that treatment can be ensured. It is crucial for healthcare professionals to use a multidisciplinary approach and be supportive and maintain a good rapport with pregnant women who abuse prescription drugs. Management includes inpatient hospitalization for detoxification and withdrawal symptoms, and in the case of opiate abuse, opiate maintenance is recommended for pregnant women for the duration of their pregnancy to reduce relapse rates and improve maternal and fetal outcomes. Other recommendations include referral for support groups and supportive housing.

  7. [Inappropriate prescription in older patients: the STOPP/START criteria].

    LENUS (Irish Health Repository)

    Delgado Silveira, Eva

    2009-09-01

    Older people are a heterogeneous group of patients, often with multiple comorbidities for which they are prescribed a large number of drugs, leading to an increased risk of adverse drug reactions (ADR) and drug interactions. This risk is compounded by physiological age-related changes in physiology, changes in drug pharmacokinetics and pharmacodynamics, as well as by disease-related, functional and social issues. Inappropriate prescription of drugs is common in the older individuals and contributes to the increased risk of ADR. Several tools have been developed to detect potentially inappropriate prescription, the most frequently used in Spain being Beers\\' criteria. However, the value of these criteria is limited, especially as they were developed in a different healthcare system. In this article, the Spanish version of a new tool to detect potentially inappropriate prescriptions-STOPP (Screening Tool of Older Person\\'s Prescriptions) and START (Screening Tool to Alert doctors to Right i.e. appropriate, indicated Treatment) criteria-is presented. The creation, development, reliability, and use of these criteria in routine practice is described and discussed. These criteria have shown better sensitivity than Beers\\' criteria in detecting prescription problems and have the added value of being able to detect not only inappropriate prescription of some drugs, but also the omission of well indicated drugs. The STOPP\\/START criteria could become a useful screening tool to improve prescription in older people.

  8. Influence of pharmaceutical marketing on prescription practices of physicians.

    Science.gov (United States)

    Narendran, Roshni; Narendranathan, M

    2013-01-01

    In India same drug molecules are sold under different brand names by different pharmaceuticals. To persuade the physicians to prescribe their brands pharmaceuticals engage in marketing techniques like giving samples, gifts, sponsoring travel etc. Many countries are striving to reduce the impact of incentives on prescription behaviour. This study explores the influence of pharmaceutical marketing on the prescription practices of doctors in India. There were 103 study subjects - 50 doctors and 53 sales personnel. Data collection was done by a self administered questionnaire. Data were collected on 36 variables which were supposed to influence prescription. The effectiveness of the promotional strategies on prescription behaviour was marked in a seven point Likert scale ranging from "not at all effective" (score=1) to "extremely effective" (score=7). Open ended questions were used to collect qualitative data. Good rapport with the doctor, launch meetings, reputation of the company, quality of the drug and brand names significantly influenced prescription behaviour, while direct mailers, advertisements in journals and giving letter pads and other brand reminders were less effective. Commonly used method of giving samples was not among the twenty most effective methods influencing prescription. Product quality and good company are still factors that influence prescription. Pharmaceutical marketing influences the choice of brands by a physician. The more expensive strategies involved in public relations are more effective. Sending mails and journal advertisements are less effective strategies. How expensive marketing strategies affect cost of the medicines has to be explored further.

  9. Geographical and temporal variations in clozapine prescription for schizophrenia

    DEFF Research Database (Denmark)

    Nielsen, Jimmi; Røge, Rasmus; Schjerning, Ole

    2012-01-01

    Despite its unsurpassed efficacy in treatment-resistant schizophrenia, clozapine remains underutilized. Trends in the prescription of clozapine in patients with ICD-10 F20.x schizophrenia were assessed using data from Danish national registers. Three substudies were carried out: (i) an assessment...... of differences in national prescription patterns between 1996 and 2007 using a cross-sectional design; (ii) a comparison of time from first schizophrenia diagnosis to first prescription of clozapine in a five-year cohort study, using the Cox regression model, of two patient groups who were first diagnosed...

  10. Future Challenges and Opportunities in Online Prescription Drug Promotion Research

    Science.gov (United States)

    Southwell, Brian G.; Rupert, Douglas J.

    2016-01-01

    Despite increased availability of online promotional tools for prescription drug marketers, evidence on online prescription drug promotion is far from settled or conclusive. We highlight ways in which online prescription drug promotion is similar to conventional broadcast and print advertising and ways in which it differs. We also highlight five key areas for future research: branded drug website influence on consumer knowledge and behavior, interactive features on branded drug websites, mobile viewing of branded websites and mobile advertisements, online promotion and non-US audiences, and social media and medication decisions. PMID:26927597

  11. The study of prescriptive and descriptive models of decision making

    Directory of Open Access Journals (Sweden)

    Ashok A Divekar

    2012-04-01

    Full Text Available The field of decision making can be loosely divided into two parts: the study of prescriptive models and the study of descriptive models. Prescriptive decision scientists are concerned with prescribing methods for making optimal decisions. Descriptive decision researchers are concerned with the bounded way in which the decisions are actually made. The statistics courses treat risk from a prescriptive, by suggesting rational methods. This paper brings out the work done by many researchers by examining the psychological factors that explain how managers deviate from rationality in responding to uncertainty.

  12. Rare Earth Market Review

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Oversupply of rare earths led to the significant price drop of rare earth mineral products and separated products in Chinese domestic market. To stabilize the price, prevent waste of resources, further improve regulation capability on domestic rare earth market and rare earth price and maintain sustaining and healthy development of rare earth industry, partial rare earth producers in Baotou and Jiangxi province projected to cease the production for one month.

  13. WAVE TECTONICS OF THE EARTH

    Directory of Open Access Journals (Sweden)

    Tatiana Yu. Tveretinova

    2015-09-01

    Full Text Available In the Earth's lithosphere, wavy alternation of positive and negative heterochronous structures is revealed; such structures are variable in ranks and separated by vergence zones of fractures and folds. In the vertical profile of the lithosphere, alternating are layers characterized by relatively plastic or fragile rheological properties and distinguished by different states of stress. During the Earth’s evolution, epochs of compression and extension are cyclically repeated, including planetary-scale phenomena which are manifested by fluctuating changes of the planet’s volume. Migration of geological and geophysical (geodynamic processes takes place at the Earth's surface and in its interior. The concept of the wave structure and evolution of the Earth's lithosphere provides explanations to the abovementioned regularities. Wavy nature of tectonic structures of the lithosphere, the cyclic recurrence of migration and geological processes in space and time can be described in terms of the multiple-order wave geodynamics of the Earth's lithosphere that refers to periodical variations of the state of stress. Effects of structure-forming tectonic forces are determined by «interference» of tangential and radial stresses of the Earth. The tangential stresses, which occur primarily due to the rotational regime of the planet, cause transformations of the Earth’s shape, redistributions of its substance in depths, the westward drift of the rock mass in its upper levels, and changes of structural deformation plans. The radial stresses, which are largely impacted by gravity, determine the gravitational differentiation of the substance, vertical flattening and sub-horizontal flow of the rock masses, and associated fold-rupture deformation. Under the uniform momentum geodynamic concept proposed by [Vikulin, Tveritinova, 2004, 2005, 2007, 2008], it is possible to provide consistent descriptions of seismic and volcanic, tectonic and geological processes

  14. A new strategy for antidepressant prescription

    Directory of Open Access Journals (Sweden)

    Francis Lavergne

    2010-11-01

    Full Text Available From our research and literature search we propose an understanding of the mechanism of action of antidepressants (ADs that should lead to increase efficacy and tolerance.We understand that ADs promote synaptic plasticity and neurogenesis. This promotion is linked with dopamine (DA stimulation. Literature shows that all ADs (chemical, electroconvulsive therapy, repetitive transcranial magnetic stimulation, sleep deprivation increase at least one neuromodulator (serotonin, noradrenaline or DA; this article focuses on DA release or turn-over in the frontal cortex. DA increase promotes synaptic plasticity with an inverted U shape dose-response curve. Specific interaction between DA and glutamate relies on DA (D1 receptors and Glutamate (NMDA receptors and/or on neurotrophic factors activation. With the understanding that all ADs have a common, final, DArgic stimulation that promotes synaptic plasticity we can predict that:1AD efficiency is related to the compound strength for inducing DArgic stimulation.2AD efficiency presents a therapeutic window that coincides with the inverted U shape DA response curve.3AD delay of action is related to a synaptogenesis and neurogenesis delay of action.4The minimum efficient dose can be found by starting at a low dosage and increasing up to the patient response. 5An increased tolerance requires a concomitant prescription of a few ADs, with different or opposite adverse effects, at a very low dose.6ADs could improve all diseases with cognitive impairments and synaptic depression by increasing synaptic plasticity and neurogenesis.

  15. Expanded pharmacy technician roles: Accepting verbal prescriptions and communicating prescription transfers.

    Science.gov (United States)

    Frost, Timothy P; Adams, Alex J

    2016-11-29

    As the role of the clinical pharmacist continues to develop and advance, it is critical to ensure pharmacists can operate in a practice environment and workflow that supports the full deployment of their clinical skills. When pharmacy technician roles are optimized, patient safety can be enhanced and pharmacists may dedicate more time to advanced clinical services. Currently, 17 states allow technicians to accept verbal prescriptions called in by a prescriber or prescriber's agent, or transfer a prescription order from one pharmacy to another. States that allow these activities generally put few legal limitations on them, and instead defer to the professional judgment of the supervising pharmacist whether to delegate these tasks or not. These activities were more likely to be seen in states that require technicians to be registered and certified, and in states that have accountability mechanisms (e.g., discipline authority) in place for technicians. There is little evidence to suggest these tasks cannot be performed safely and accurately by appropriately trained technicians, and the track record of success with these tasks spans four decades in some states. Pharmacists can adopt strong practice policies and procedures to mitigate the risk of harm from verbal orders, such as instituting read-back/spell-back techniques, or requiring the indication for each phoned-in medication, among other strategies. Pharmacists may also exercise discretion in deciding to whom to delegate these tasks. As the legal environment becomes more permissive, we foresee investment in more robust education and training of technicians to cover these activities. Thus, with the adoption of robust practice policies and procedures, delegation of verbal orders and prescription transfers can be safe and effective, remove undue stress on pharmacists, and potentially free up pharmacist time for higher-order clinical care. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. How Typewriters Changed Correspondence: An Analysis of Prescription and Practice.

    Science.gov (United States)

    Walker, Sue

    1984-01-01

    Notes changes in the visual organization of correspondence brought about by the typewriter. Discusses the development of these changes, drawing examples both from the prescriptions for and the practice of commercial correspondence. (FL)

  17. The Language of Civil Engineering: Descriptive, Prescriptive, and Persuasive.

    Science.gov (United States)

    Machauf, Liora

    1990-01-01

    Focuses on the language of civil engineering as manifested in the professional journal "Civil Engineering ASCE." Articles are analyzed, both syntactically and lexically, in terms of three major rhetorical functions: description, prescription, and persuasion. (17 references) (GLR)

  18. Buying Prescription Medicine Online: A Consumer Safety Guide

    Science.gov (United States)

    ... Seniors Tips for Parents En Español Prescription Drug Advertising Information for Healthcare Professionals (Drugs) FDA Drug Info ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  19. Investigation of Medication Errors: A Prescription Survey from Sri ...

    African Journals Online (AJOL)

    Conclusion: Prescription errors are common in outpatient settings of Aluthgama and Kandy areas in. Sri Lanka. ..... irrational drug use in India were similar to the results that were .... and nature of dosing errors in paediatric medications:.

  20. 75 FR 16235 - Electronic Prescriptions for Controlled Substances

    Science.gov (United States)

    2010-03-31

    ...; these include opioids, stimulants, depressants, hallucinogens, anabolic steroids, and drugs that are... consequences of prescription drug abuse are seen in the data collected by the Substance Abuse and Mental...

  1. The “Black Box” of Prescription Drug Diversion

    Science.gov (United States)

    Inciardi, James A.; Surratt, Hilary L.; Cicero, Theodore J.; Kurtz, Steven P.; Martin, Steven S.; Parrino, Mark W.

    2009-01-01

    A variety of surveys and studies are examined in an effort to better understand the scope of prescription drug diversion and to determine if there are consistent patterns of diversion among various populations of prescription drug abusers. Data are drawn from the RADARS® System, the National Survey of Drug Use and Health (NSDUH), the Delaware School Survey, and a series of quantitative and qualitative studies conducted in Miami, Florida. The data suggest that the major sources of diversion include drug dealers, friends and relatives, smugglers, pain patients, and the elderly, but these vary by the population being targeted. In all of the studies examined, the use of the Internet as a source for prescription drugs is insignificant. Little is known about where drug dealers are obtaining their supplies, and as such, prescription drug diversion is a “black box” requiring concentrated systematic study. PMID:20155603

  2. Prescription and Cost Consideration at a Diabetic Clinic in Ibadan ...

    African Journals Online (AJOL)

    opsig

    Prescription and Cost Consideration at a Diabetic Clinic in Ibadan,. Nigeria: A Report ... drugs with proven efficacy based on best evidence, the prevailing social ... pharmacy using the current hospital drug-pricing list calculated the cost of the ...

  3. Which Classes of Prescription Drugs Are Commonly Misused?

    Science.gov (United States)

    ... may include restlessness, muscle and bone pain, insomnia, diarrhea, vomiting, cold flashes with goose bumps, and involuntary leg movements. 29 Misuse of prescription opioids is also a risk factor for transitioning to heroin use. Read more about ...

  4. Opioid prescriptions before and after high-energy trauma

    DEFF Research Database (Denmark)

    Zwisler, Stine T; Hallas, Jesper; Larsen, Morten S

    2015-01-01

    OBJECTIVE: To describe the legal use of opioids in adult patients before and after high-energy trauma. DESIGN: The study was a retrospective database study. SETTING: Clinical care outside hospitals. PATIENTS: All patients who suffered high-energy trauma and were brought to Odense University...... Hospital (OUH), Denmark, in 2007 and 2008 were retrieved from the trauma database. These patients were linked with data on opioid use from the regional prescription database. In all, 938 patients were included. MAIN OUTCOME MEASURE: Redemption of opioid prescription during the 6 months prior...... to a multitrauma or redemption of two or more prescriptions for opioids 6 months or later after a multitrauma. RESULTS: Of the 938 patients brought to OUH with severe trauma within the study period, 61 patients died (7 percent) and six of these had redeemed prescriptions for opioids within 6 months prior...

  5. Toward Validation of the Diagnostic-Prescriptive Model

    Science.gov (United States)

    Ysseldyke, James E.; Sabatino, David A.

    1973-01-01

    Criticized are recent research efforts to validate the diagnostic prescriptive model of remediating learning disabilities, and proposed is a 6-step psychoeducational model designed to ascertain links between behavioral differences and instructional outcomes. (DB)

  6. Prescription patterns and utilisation of antihypertensive drugs in a ...

    African Journals Online (AJOL)

    Prescription patterns and utilisation of antihypertensive drugs in a specialist ... use in the management of essential hypertension in a specialist hospital and its ... of encounters, there were a total of 1544 drugs and 28 non-drug interventions.

  7. Pattern of Prescription of Antibiotics among Dental Practitioners in ...

    African Journals Online (AJOL)

    consistency in the antibiotic prescription pattern among dentists in Jeddah and overall low adherence to the ..... manuscript editing and review. Appendix I: Clinical case ... adhesion deficiency, antibiotic therapy is indicated. a*Adapted from ...

  8. Immersible ergocycle prescription as a function of relative exercise intensity

    Directory of Open Access Journals (Sweden)

    Mauricio Garzon

    2017-06-01

    Conclusion: The %HRR–%VO2R relationship appears to be the most accurate for exercise training prescription on IE. This study offers new tools to better prescribe, control, and individualize exercise intensity on IE.

  9. Forest Management Prescription : Compartment 9 : Mingo National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is the Forest Management Prescription for Compartment 9 of Mingo NWR. It provides a description of the compartment, management objectives, proposed management...

  10. prescriptions involving analgesic drugs at a secondary health facility ...

    African Journals Online (AJOL)

    per patient were recorded and prescriptions involving analgesics were further ... documentation of any untoward effects in the over ... files were sent to the Pharmacy Department of the ..... Efficacy and safety of metamizol vs. acetylsalicylic acid.

  11. Basic Stand Alone Medicare Prescription Drug Events PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This is a Public Use File for Prescription Drug Events drawn from the 2008 Beneficiary Summary File of Medicare beneficiaries enrolled during the calendar year 2008,...

  12. Opioid prescriptions before and after high-energy trauma

    DEFF Research Database (Denmark)

    Zwisler, Stine T; Hallas, Jesper; Larsen, Morten S

    2015-01-01

    OBJECTIVE: To describe the legal use of opioids in adult patients before and after high-energy trauma. DESIGN: The study was a retrospective database study. SETTING: Clinical care outside hospitals. PATIENTS: All patients who suffered high-energy trauma and were brought to Odense University...... Hospital (OUH), Denmark, in 2007 and 2008 were retrieved from the trauma database. These patients were linked with data on opioid use from the regional prescription database. In all, 938 patients were included. MAIN OUTCOME MEASURE: Redemption of opioid prescription during the 6 months prior...... to a multitrauma or redemption of two or more prescriptions for opioids 6 months or later after a multitrauma. RESULTS: Of the 938 patients brought to OUH with severe trauma within the study period, 61 patients died (7 percent) and six of these had redeemed prescriptions for opioids within 6 months prior...

  13. Galactic habitable zone around M and FGK stars with chemical evolution models that include dust

    Science.gov (United States)

    Spitoni, E.; Gioannini, L.; Matteucci, F.

    2017-09-01

    Context. The Galactic habitable zone is defined as the region with a metallicity that is high enough to form planetary systems in which Earth-like planets could be born and might be capable of sustaining life. Life in this zone needs to survive the destructive effects of nearby supernova explosion events. Aims: Galactic chemical evolution models can be useful tools for studying the galactic habitable zones in different systems. Our aim here is to find the Galactic habitable zone using chemical evolution models for the Milky Way disk, adopting the most recent prescriptions for the evolution of dust and for the probability of finding planetary systems around M and FGK stars. Moreover, for the first time, we express these probabilities in terms of the dust-to-gas ratio of the interstellar medium in the solar neighborhood as computed by detailed chemical evolution models. Methods: At a fixed Galactic time and Galactocentric distance, we determined the number of M and FGK stars that host earths (but no gas giant planets) that survived supernova explosions, using the formalism of our Paper I. Results: The probabilities of finding terrestrial planets but not gas giant planets around M stars deviate substantially from the probabilities around FGK stars for supersolar values of [Fe/H]. For both FGK and M stars, the maximum number of stars hosting habitable planets is at 8 kpc from the Galactic Center when destructive effects by supernova explosions are taken into account. Currently, M stars with habitable planets are ≃10 times more frequent than FGK stars. Moreover, we provide a sixth-order polynomial fit (and a linear fit, but that is more approximated) for the relation found with chemical evolution models in the solar neighborhood between the [Fe/H] abundances and the dust-to-gas ratio. Conclusions: The most likely Galactic zone in which to find terrestrial habitable planets around M and FGK stars is the annular 2 kpc wide region that is centered at 8 kpc from the

  14. An Exercise Prescription Intervention Program with Periodic Ergometric Grading

    Science.gov (United States)

    Owen, C. A.; Beard, E. F.

    1970-01-01

    A long term exercise prescription type of physical conditioning program has been available to executive personnel of the NASA Manned Spacecraft Center for the past two years. Periodic ergometric testing with a heart rate controlled, automatically programmed, bicycle ergometer is used to follow the individual's progress and appropriately alter his exercise prescription from time to time. Such a program appears feasible, and acceptance is excellent, dropout rates small and periodic testing participation good. Subjects training diligently can maintain satisfactory levels of conditioning.

  15. Transferring Lens Prescriptions Between Lens-Design Programs

    Science.gov (United States)

    Stacy, John E.; Wooley, Laura; Carlin, Brian

    1989-01-01

    Optical Lens Prescription Data Formatter computer program enables user to transfer complicated lens prescriptions quickly and easily from one major optical-design program to another and back again. One can take advantage of inherent strength of either program. Programs are ACCOS V from Scientific Calculations, Inc., of Fishers, NY, and CODE V from Optical Research Associates of Pasadena, CA. VAX version written in FORTRAN.

  16. Rationality of Antimicrobial Prescriptions in Community Pharmacy Users.

    Directory of Open Access Journals (Sweden)

    Sara I V C Lima

    Full Text Available Although there is a conflict between the treatment benefits for a single individual and society, restrictions on antibiotic use are needed to reduce the prevalence of resistance to these drugs, which is the main result of irrational use. Brazil, cataloged as a pharmemerging market, has implemented restrictive measures for the consumption of antibiotics. The objective of this study was to investigate the quality of antimicrobial prescriptions and user knowledge of their treatment with these drugs.A two-stage cross-sectional, combined and stratified survey of pharmacy users holding an antimicrobial prescription was conducted in the community between May and November 2014. A pharmacist analyzed each prescription for legibility and completeness, and applied a structured questionnaire to the users or their caregivers on their knowledge regarding treatment and user sociodemographic data. An estimated 29.3% of prescriptions had one or more illegible items, 91.3% had one or more missing items, and 29.0% had both illegible and missing items. Dosing schedule and patient identification were the most commonly unreadable items in prescriptions, 18.81% and 12.14%, respectively. The lack of complete patient identification occurred in 90.53% of the prescriptions. It is estimated that 40.3% of users have used antimicrobials without prescription and that 46.49% did not receive any guidance on the administration of the drug.Despite the measures taken by health authorities to restrict the misuse of antimicrobials, it was observed that prescribers still do not follow the criteria of current legislation, particularly relating to items needed for completion of the prescription. Moreover, users receive little information about their antimicrobial treatment.

  17. Self-prescription practices in recent Latino immigrants.

    Science.gov (United States)

    Coffman, Maren J; Shobe, Marcia A; O'Connell, Beth

    2008-01-01

    Self-prescription involves the purchase and use of restricted medications without medical advice. Although common in Central and South American countries, little is known about this practice among Latino immigrants in the United States. The purpose of this study, therefore, was to explore how Latino immigrants obtain and use prescription medications without accessing the formal health care system. This exploratory descriptive study used focus groups to gain an understanding of the use of prescription medications without medical care. Three focus group discussions were held with 19 adult Latino immigrants who were new residents in the United States, and did not have health insurance; most were undocumented. Analysis of the data revealed 4 major themes: (a) health care barriers, (b) cultural norms, (c) self-care, and (d) self-prescription. The data indicate that this population experiences significant barriers to accessing health care, forcing them to seek treatment alternatives including the purchase and use of drugs manufactured in Mexico. There are many public health and safety concerns related to self-prescription practices. Nurses need to be aware of the barriers to health care that lead to these potentially dangerous medication practices, and to recognize and understand self-prescription.

  18. Predicting prosthetic prescription after major lower-limb amputation

    Directory of Open Access Journals (Sweden)

    Linda Resnik, PT, PhD, OCS

    2015-09-01

    Full Text Available We describe prosthetic limb prescription in the first year following lower-limb amputation and examine the relationship between amputation level, geographic region, and prosthetic prescription. We analyzed 2005 to 2010 Department of Veterans Affairs (VA Inpatient and Medical Encounters SAS data sets, Vital Status death data, and National Prosthetic Patient Database data for 9,994 Veterans who underwent lower-limb amputation at a VA hospital. Descriptive statistics and bivariates were examined. Cox proportional hazard models identified factors associated with prosthetic prescription. Analyses showed that amputation level was associated with prosthetic prescription. The hazard ratios (HRs were 1.41 for ankle amputation and 0.46 for transfemoral amputation compared with transtibial amputation. HRs for geographic region were Northeast = 1.49, Upper Midwest = 1.26, and West = 1.39 compared with the South (p < 0.001. African American race, longer length of hospital stay, older age, congestive heart failure, paralysis, other neurological disease, renal failure, and admission from a nursing facility were negatively associated with prosthetic prescription. Being married was positively associated. After adjusting for patient characteristics, people with ankle amputation were most likely to be prescribed a prosthesis and people with transfemoral amputation were least likely. Geographic variation in prosthetic prescription exists in the VA and further research is needed to explain why.

  19. Illicit Use of Prescription Opiates among Graduate Students.

    Science.gov (United States)

    Varga, Matthew D; Parrish, Mark

    2015-01-01

    Through this study the authors assessed the prevalence rate, reasons for use, and poly-substance use of prescription opiates among graduate students. The authors employed a cross-sectional survey research design using an online, self-administered questionnaire to assess the prevalence rates of prescription opiate use among graduate students (N = 1,033), reasons for use, and their likelihood for poly-substance use. The survey was e-mailed to 5,000 graduate students. Graduate students (19.7%) reported illicit use of prescription opiates in their lifetime and 6.6% reported past-year illicit use. Those who indicated illicitly using prescription opiates did so for self-medication reasons; a few respondents indicated recreational use. Students using prescription opiates were 75% less likely to use marijuana; 79% less likely to use cocaine; and 75% less likely to use ecstasy. Graduate students are illicitly using prescription opiates, but primarily for self-medication, and, while doing so, are less likely to use other substances.

  20. Description, prescription and the choice of discount rates

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Seth D. [Rock Ethics Institute, Pennsylvania State University, 201 Willard Building, University Park, PA 16802 (United States); Department of Geography, Pennsylvania State University, 302 Walker Building, University Park, PA 16802 (United States)

    2009-11-15

    The choice of discount rates is a key issue in the analysis of long-term societal issues, in particular environmental issues such as climate change. Approaches to choosing discount rates are generally placed into two categories: the descriptive approach and the prescriptive approach. The descriptive approach is often justified on grounds that it uses a description of how society discounts instead of having analysts impose their own discounting views on society. This paper analyzes the common forms of the descriptive and prescriptive approaches and finds that, in contrast with customary thinking, both forms are equally descriptive and prescriptive. The prescriptions concern who has standing (i.e. who is included) in society, how the views of these individuals are measured, and how the measurements are aggregated. Such prescriptions are necessary to choose from among the many possible descriptions of how society discounts. The descriptions are the measurements made given a choice of measurement technique. Thus, the labels 'descriptive approach' and 'prescriptive approach' are deeply misleading, as analysts cannot avoid imposing their own views on society. (author)

  1. Doctor Shopping Behavior and the Diversion of Prescription Opioids.

    Science.gov (United States)

    Simeone, Ronald

    2017-01-01

    "Doctor shopping" as a means of prescription opioid diversion is examined. The number and percentage of prescriptions and morphine-equivalent milligrams diverted in this manner are estimated by state and molecule for the period 2008-2012. Eleven billion prescriptions with unique patient, doctor, and pharmacy identifiers were used to construct diversion "events" that involved between 1 and 6 unique doctors and between 1 and 6 unique pharmacies. Diversion thresholds were established based on the probability of each contingency. A geographically widespread decline occurred between 2008 and 2012. The number of prescriptions diverted fell from approximately 4.30 million (1.75% of all prescriptions) in 2008 to approximately 3.37 million (1.27% of all prescriptions) in 2012, and the number of morphine-equivalent milligrams fell from approximately 6.55 metric tons (2.95% of total metric tons) in 2008 to approximately 4.87 metric tons (2.19% of total metric tons) in 2012. Diversion control efforts have likely been effective. But given increases in opioid-related deaths, opioid-related drug treatment admissions, and the more specific resurgence of heroin-related events, it is clear that additional public health measures are required.

  2. The earth orbiting space debris

    Directory of Open Access Journals (Sweden)

    Rossi A.

    2005-01-01

    Full Text Available The space debris population is similar to the asteroid belt, since it is subject to a process of high-velocity mutual collisions that affects the long-term evolution of its size distribution. Presently, more than 10 000 artificial debris particles with diameters larger than 10 cm (and more than 300 000 with diameters larger than 1 cm are orbiting the Earth, and are monitored and studied by a large network of sensors around the Earth. Many objects of different kind compose the space debris population, produced by different source mechanisms ranging from high energy fragmentation of large spacecraft to slow diffusion of liquid metal. The impact against a space debris is a serious risk that every spacecraft must face now and it can be evaluated with ad-hoc algorithms. The long term evolution of the whole debris population is studied with computer models allowing the simulation of all the known source and sink mechanisms. One of these codes is described in this paper and the evolution of the debris environment over the next 100 years, under different traffic scenarios, is shown, pointing out the possible measures to mitigate the growth of the orbital debris population. .

  3. A Mission to Earth's Center

    Science.gov (United States)

    Olson, P.

    2016-12-01

    The last few decades have witnessed extraordinary progress on Earth's deep interior, particularly for Earth's core. Notable examples include seismic detection of fine structure and heterogeneity from the CMB to the depths of the inner core; improved constraints on the thermal regime and critical physical properties; direct experimental access to core pressures and temperatures; partial resolution of geomagnetic history into the deep past, new cosmochemical constraints on core formation, plus a first-order solution of the dynamo problem. Nevertheless, many fundamental questions about Earth's core remain unanswered, representing significant impediments to further understanding, not just of the Earth system, but also the interiors of other planets. A partial list of unsolved problems includes the composition of the core especially its light element inventory, the nature of heterogeneity in the core and its dynamical significance, quantifying heat and mass exchanges between core and mantle, the record of core evolution exemplified by inner core nucleation and the magnetic superchron cycle, and the role of core formation in governing Earth history. A more concerted and better-focused interdisciplinary effort is needed to resolve these long-standing problems, one that is comparable in its scale and structure to a planetary exploration mission. Such a Mission to Earth's Center would foster technological developments aimed specifically at these questions, such as seismic arrays designed for imaging the core, experimental capability for determining the phase diagram of the core, resolution of geomagnetic history into the deep past, plus next-generation dynamical models for the mantle, the core, and their interaction.

  4. Bodily differences between Cold- and Heat-prescription groups in Sasang medicine

    Directory of Open Access Journals (Sweden)

    Young Joo Park

    2016-06-01

    Conclusion: In the SY-type men, the chest circumference was significantly greater in the Heat-prescription group compared to the Cold-prescription group. In the TE-type men, the rib-to-pelvic circumference ratio was significantly higher in the Heat-prescription group than in the Cold-prescription group.

  5. Earth from Above

    Science.gov (United States)

    Stahley, Tom

    2006-01-01

    Google Earth is a free online software that provides a virtual view of Earth. Using Google Earth, students can view Earth by hovering over features and locations they preselect or by serendipitously exploring locations that catch their fascination. Going beyond hovering, they can swoop forward and even tilt images to make more detailed…

  6. An analytical treatment for three neutrino oscillations in the Earth

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Arevalo, A.A.; D' Olivo, J.C.; Supanitsky, A.D. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, 04510, Mexico, D.F. (Mexico)

    2012-08-15

    A simple, and at the same time accurate, description of the Earth matter effects on the oscillations between three neutrino flavors is given in terms of the Magnus expansion for the evolution operator.

  7. Rare Earth Resolution

    Institute of Scientific and Technical Information of China (English)

    Mei Xinyu

    2012-01-01

    BEFORE the early 1970s, China had no rare earth exports, and the world rare earth market was dominated by the United States, Europe and Japan. In the 1970s, China began to enter the world rare earth market and its share has picked up sharply in the following decades. Today, having the monopoly over global rare earth production, China must improve the benefits from rare earth production, not only from producing individual rare earth products, but also from mastering the intensive processing of rare earth products.

  8. Defining risk of prescription opioid overdose: pharmacy shopping and overlapping prescriptions among long-term opioid users in medicaid.

    Science.gov (United States)

    Yang, Zhuo; Wilsey, Barth; Bohm, Michele; Weyrich, Meghan; Roy, Kakoli; Ritley, Dominique; Jones, Christopher; Melnikow, Joy

    2015-05-01

    Use of multiple pharmacies concurrently (pharmacy shopping) and overlapping prescriptions may be indicators of potential misuse or abuse of prescription opioid medications. To evaluate strategies for identifying patients at high risk, we first compared different definitions of pharmacy shopping and then added the indicator of overlapping opioid prescriptions. We identified a cohort of 90,010 Medicaid enrollees who used ≥ 3 opioid prescriptions for ≥ 90 days during 2008 to 2010 from a multistate Medicaid claims database. We compared the diagnostic odds ratios for opioid overdose events of 9 pharmacy shopping definitions. Within a 90-day interval, a threshold of 4 pharmacies had the highest diagnostic odds ratio and was used to define pharmacy shopping. The overdose rate was higher in the subgroup with overlapping prescriptions (18.5 per 1,000 person-years [PYs]) than in the subgroup with pharmacy shopping as the sole indicator (10.7 per 1,000 PYs). Among the subgroup with both conditions, the overdose rate was 26.3 per 1,000 PYs, compared with 4.3 per 1,000 PYs for those with neither condition. Overlapping opioid prescriptions and pharmacy shopping measures had adjusted hazard ratios of 3.0 and 1.8, respectively, for opioid overdose. Using these measures will improve accurate identification of patients at highest risk of opioid overdose, the first step in implementing targeted prevention policies. Long-term prescription opioid use may lead to adverse events, including overdose. Both pharmacy shopping and overlapping opioid prescriptions are associated with adverse outcomes. This study demonstrates that using both indicators will better identify those at high risk of overdose. Published by Elsevier Inc.

  9. Astrobiology: Life on Earth (and Elsewhere?)

    Science.gov (United States)

    Des Marais, David J.

    2016-01-01

    Astrobiology investigates the origins, evolution and distribution of life in the universe. Scientists study how stellar systems and their planets can create planetary environments that sustain biospheres. They search for biosignatures, which are objects, substances and or patterns that indicate the presence of life. Studies of Earth's early biosphere enhance these search strategies and also provide key insights about our own origins.

  10. Cosmic Rays at Earth

    Science.gov (United States)

    Grieder, P. K. F.

    In 1912 Victor Franz Hess made the revolutionary discovery that ionizing radiation is incident upon the Earth from outer space. He showed with ground-based and balloon-borne detectors that the intensity of the radiation did not change significantly between day and night. Consequently, the sun could not be regarded as the sources of this radiation and the question of its origin remained unanswered. Today, almost one hundred years later the question of the origin of the cosmic radiation still remains a mystery. Hess' discovery has given an enormous impetus to large areas of science, in particular to physics, and has played a major role in the formation of our current understanding of universal evolution. For example, the development of new fields of research such as elementary particle physics, modern astrophysics and cosmology are direct consequences of this discovery. Over the years the field of cosmic ray research has evolved in various directions: Firstly, the field of particle physics that was initiated by the discovery of many so-called elementary particles in the cosmic radiation. There is a strong trend from the accelerator physics community to reenter the field of cosmic ray physics, now under the name of astroparticle physics. Secondly, an important branch of cosmic ray physics that has rapidly evolved in conjunction with space exploration concerns the low energy portion of the cosmic ray spectrum. Thirdly, the branch of research that is concerned with the origin, acceleration and propagation of the cosmic radiation represents a great challenge for astrophysics, astronomy and cosmology. Presently very popular fields of research have rapidly evolved, such as high-energy gamma ray and neutrino astronomy. In addition, high-energy neutrino astronomy may soon initiate as a likely spin-off neutrino tomography of the Earth and thus open a unique new branch of geophysical research of the interior of the Earth. Finally, of considerable interest are the biological

  11. [Prescription appropriateness: Indication of citicoline in Primary Care].

    Science.gov (United States)

    Padilla Luz, A; Reyes Rodríguez, J F; Gómez Rodríguez de Acuña, A; González Gómez, C M; Álvarez Dorta, I; Pérez Cánovas, M E

    2015-01-01

    The economic situation has made it necessary to optimize resources by adjusting the pharmaceutical expenditure. Citicoline was (2011) the 10th drug by rank of billed amount. Its approved indications are stroke (acute and sub-acute) and head injury, but not cognitive decline associated with age, the presumed indication for most of its use. To assess the conditions of use of citicoline in the Health Area of Tenerife, in order to detect deviations from the indications of use as stipulated in the prescribing information sheet and the pattern of prescription, with emphasis on the analysis of its use in dementia where currently it has no indication or evidence to support it. Cross-sectional study of prescription-indication. A 680 patient sample, segmented by reference hospital (error±5%; CI: 0.95%; P=0.5) was taken from the 4036 patients with a prescription of citicoline billed during august-october 2011 (obtained from the prescription database program, Farmacanarias). We found that 123 patients (18.1%) had an appropriate indication. By including the prescription regimen, 28 patients (4.1%) had adequate indication and dose levels, and in only 2 patients (0.2%) an appropriate indication, dosage and duration were found. "The correct prescription-indication" of citicoline is inappropiate in almost all patients studied. Impact actions are needed in order to optimize prescription, improve patient safety by reducing potential interactions, and the occurrence of adverse effects, and improve efficiency by promoting savings. Copyright © 2013 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Pediatric emergency department discharge prescriptions requiring pharmacy clarification.

    Science.gov (United States)

    Caruso, Michelle C; Gittelman, Michael A; Widecan, Michelle L; Luria, Joseph W

    2015-06-01

    The aims of the study were to analyze and classify reasons why retail pharmacies need to contact the pediatric emergency department (PED) for clarification on outpatient prescriptions generated using an electronic prescribing system and to categorize the severity of errors captured. A retrospective chart review was conducted at a PED that cares for approximately 92,000 patients annually. All pharmacy callbacks documented in the electronic medical record between August 1, 2008 and July 31, 2009 were included. A datasheet was used to capture patient demographics (age, sex, race, insurance), prescriptions written, and reason for callback. Each call was then assigned a severity level, and time to respond to all calls was estimated. Frequencies were used to analyze the data. A total of 731 errors for 695 callbacks were analyzed from 49,583 prescriptions written at discharge. The most common errors included administrative/insurance issues 342/731 (47%) and prescription writing errors 298/731 (41%). The errors were classified as insignificant (340/729 [47%]), problematic (288/729 [40%]), significant (77/729 [11%]), serious (12/729 [1.64%]), and severe (12/729 [1.64%]). Almost 96% of errant prescriptions were not able to be filled as originally written and required a change by the prescriber. These calls required approximately 127 hours to complete. Prescription errors requiring a pharmacy callback are typically insignificant. However, 13.8% of callbacks about an error were considered significant, serious, or severe. Automated dose checking and verifying insurance coverage of prescribed medications should be considered essential components of prescription writing in a PED.

  13. The influence of changes in hospital drug formulary on the prescription of proton pump inhibitors

    Directory of Open Access Journals (Sweden)

    Raquel Vázquez-Mourelle

    2017-01-01

    Full Text Available Objective: To analyze the impact of introducing omeprazole in the drug formulary of the Hospital de Barbanza on prescriptions made in hospital and out-of-hospital (Outpatient Units and Primary Care for all Proton Pump Inhibitors (PPIs. Material and methods: A 36-month retrospective descriptive study in a level I hospital. The basic units of work are Dose-Population- Day in the outpatient setting, and the Defined Daily Dose/stays-day for hospitalized patients; the proportion of DDDs for omeprazole vs. the rest of PPIs is used as measure of efficiency. For statistical analysis, we built a segmented regression model. Results: In the outpatient units, there are statistically significant changes for pantoprazole and rabeprazole. The first drug, which was stable before the intervention, suffered an immediate decrease; rabeprazole, which was increasing before the intervention, presented a subsequent downward trend. In Primary Care, a statistically significant change was confirmed for pantoprazole, with a long-term decreasing trend. In hospitalization, statistically significant changes were observed for pantoprazole and omeprazole; the first one with an immediate decrease and a long-term tendency to decrease, while omeprazole experienced an immediate increase and long-term growth. The evolution of the omeprazole percentage vs. all PPIs showed increases in all three scenarios. Conclusions: A shift to a more efficient prescription of PPIs was observed in all healthcare settings following the introduction of omeprazole in the hospital drug formulary. The inclusion of efficient drugs, or the removal of those inefficient, can be a potentially useful tool in order to improve prescription profiles.

  14. A New Prescription for the Mass-loss Rates of WC and WO Stars

    Science.gov (United States)

    Tramper, F.; Sana, H.; de Koter, A.

    2016-12-01

    We present a new empirical prescription for the mass-loss rates of carbon- and oxygen-sequence Wolf-Rayet stars as a function of their luminosity, surface chemical composition, and initial metallicity. The new prescription is based on results of detailed spectral analyses of WC and WO stars and improves the often applied Nugis and Lamers relation. We find that the mass-loss rates of WC and WO stars (with X = 0 and Y ≲ 0.98) can be expressed as {log} \\dot{M}=-9.20+0.85{log}(L/L ⊙) + 0.44 log Y + 0.25 log (Z Fe/Z Fe,⊙). This relation is based on mass-loss determinations that assume a volume-filling factor of 0.1, but the prescription can easily be scaled to account for other volume-filling factors. The residual of the fit is σ = 0.06 dex. We investigated whether the relation can also describe the mass loss of hydrogen-free WN stars and showed that it can when an adjustment of the metallicity dependence ({log} \\dot{M}\\propto 1.3{log}({Z}{Fe}/{Z}{Fe,⊙ })) is applied. Compared to that of Nugis and Lamers, \\dot{M} is less sensitive to the luminosity and the surface abundance, implying a stronger mass loss of massive stars in their late stages of evolution. The modest metallicity dependence implies that if WC or WO stars are formed in metal-deficient environments, their mass-loss rates are higher than currently anticipated. These effects may result in the formation of a larger number of SNe Ic and fewer black holes and may favor the production of superluminous SNe Ic through interaction with C- and O-rich circumstellar material or dense stellar wind.

  15. Cultural Evolution and SETI

    Science.gov (United States)

    Dick, S. J.

    2009-12-01

    The Drake Equation for the number of radio communicative technological civilizations in the Galaxy encompasses three components of cosmic evolution: astronomical, biological and cultural. Of these three, cultural evolution totally dominates in terms of the rapidity of its effects. Yet, SETI scientists do not take cultural evolution into account, perhaps for understandable reasons, since cultural evolution is not well-understood even on Earth and is unpredictable in its outcome. But the one certainty for technical civilizations billions, millions, or even thousands of years older than ours is that they will have undergone cultural evolution. Cultural evolution potentially takes place in many directions, but this paper argues that its central driving force is the maintenance, improvement and perpetuation of knowledge and intelligence, and that to the extent intelligence can be improved, it will be improved. Applying this principle to life in the universe, extraterrestrials will have sought the best way to improve their intelligence. One possibility is that they may have long ago advanced beyond flesh-and-blood to artificial intelligence, constituting a postbiological universe. Although this subject has been broached, it has not been given the attention it is due from its foundation in cultural evolution. Nor has the idea of a postbiological universe been carried to its logical conclusion, including a careful analysis of the implications for SETI. SETI scientists, social scientists, and experts in AI should consider the strengths and weaknesses of this new paradigm.

  16. Use of a generic protocol in documentation of prescription errors in Estonia, Norway and Sweden

    Directory of Open Access Journals (Sweden)

    Haavik S

    2012-06-01

    Full Text Available Pharmacists have an important role in detecting, preventing, and solving prescription problems, which if left unresolved, may pose a risk of harming the patient.Objective: The objectives of this study were to evaluate the feasibility of a generic study instrument for documentation of prescription problems requiring contact with prescriber before dispensing. The study was organized: 1 by countries: Estonia, Norway and Sweden; 2 by type of prescriptions: handwritten prescriptions, printouts of prescriptions in the electronic medical record and electronically transmitted prescriptions to pharmacies; and 3 by recording method - self-completion by pharmacists and independent observers.Methods: Observational study with independent observers at community pharmacies in Estonia (n=4 and Sweden (n=7 and self-completed protocols in Norway (n=9.Results: Pharmacists’ in Estonia contacted the prescriber for 1.47% of the prescriptions, about 3 times as often as in Norway (0.45% and Sweden (0.38%. Handwritten prescriptions dominated among the problem prescriptions in Estonia (73.2%, printouts of prescriptions in the electronic medical record (89.1% in Norway and electronically transmitted prescriptions to pharmacies (55.9% in Sweden.More administrative errors were identified on handwritten prescriptions and printouts of prescriptions in the electronic medical record in Estonia and in Norway compared with electronically transmitted prescriptions to pharmacies in Sweden (p<0.05 for prescription types and p<0.01 for countries. However, clinically important errors and delivery problems appeared equally often on the different types of prescriptions. In all three countries, only few cases of drug interactions and adverse drug reactions were identified.Conclusion: Despite the different patterns of prescription problems in three countries, the instrument was feasible and can be regarded appropriate to document and classify prescription problems necessitating contact

  17. The Lifeworld Earth and a Modelled Earth

    Science.gov (United States)

    Juuti, Kalle

    2014-01-01

    The goal of this paper is to study the question of whether a phenomenological view of the Earth could be empirically endorsed. The phenomenological way of thinking considers the Earth as a material entity, but not as an object as viewed in science. In the learning science tradition, tracking the process of the conceptual change of the shape of the…

  18. The Lifeworld Earth and a Modelled Earth

    Science.gov (United States)

    Juuti, Kalle

    2014-01-01

    The goal of this paper is to study the question of whether a phenomenological view of the Earth could be empirically endorsed. The phenomenological way of thinking considers the Earth as a material entity, but not as an object as viewed in science. In the learning science tradition, tracking the process of the conceptual change of the shape of the…

  19. Predicting prosthetic prescription after major lower-limb amputation.

    Science.gov (United States)

    Resnik, Linda; Borgia, Matthew

    2015-01-01

    We describe prosthetic limb prescription in the first year following lower-limb amputation and examine the relationship between amputation level, geographic region, and prosthetic prescription. We analyzed 2005 to 2010 Department of Veterans Affairs (VA) Inpatient and Medical Encounters SAS data sets, Vital Status death data, and National Prosthetic Patient Database data for 9,994 Veterans who underwent lower-limb amputation at a VA hospital. Descriptive statistics and bivariates were examined. Cox proportional hazard models identified factors associated with prosthetic prescription. Analyses showed that amputation level was associated with prosthetic prescription. The hazard ratios (HRs) were 1.41 for ankle amputation and 0.46 for transfemoral amputation compared with transtibial amputation. HRs for geographic region were Northeast = 1.49, Upper Midwest = 1.26, and West = 1.39 compared with the South (p amputation were most likely to be prescribed a prosthesis and people with transfemoral amputation were least likely. Geographic variation in prosthetic prescription exists in the VA and further research is needed to explain why.

  20. Prescription Opioid Abuse: Challenges and Opportunities for Payers

    Science.gov (United States)

    Katz, Nathaniel P.; Birnbaum, Howard; Brennan, Michael J.; Freedman, John D.; Gilmore, Gary P.; Jay, Dennis; Kenna, George A.; Madras, Bertha K.; McElhaney, Lisa; Weiss, Roger D.; White, Alan G.

    2013-01-01

    Objective Prescription opioid abuse and addiction are serious problems with growing societal and medical costs, resulting in billions of dollars of excess costs to private and governmental health insurers annually. Though difficult to accurately assess, prescription opioid abuse also leads to increased insurance costs in the form of property and liability claims, and costs to state and local governments for judicial, emergency, and social services. This manuscript’s objective is to provide payers with strategies to control these costs, while supporting safe use of prescription opioid medications for patients with chronic pain. Method A Tufts Health Care Institute Program on Opioid Risk Management meeting was convened in June 2010 with private and public payer representatives, public health and law enforcement officials, pain specialists, and other stakeholders to present research, and develop recommendations on solutions that payers might implement to combat this problem. Results While protecting access to prescription opioids for patients with pain, private and public payers can implement strategies to mitigate financial risks associated with opioid abuse, using internal strategies, such as formulary controls, claims data surveillance, and claims matching; and external policies and procedures that support and educate physicians on reducing opioid risks among patients with chronic pain. Conclusion Reimbursement policies, incentives, and health technology systems that encourage physicians to use universal precautions, to consult prescription monitoring program (PMP) data, and to implement Screening, Brief Intervention, and Referral to6Treatment protocols, have a high potential to reduce insurer risks while addressing a serious public health problem. PMID:23725361

  1. RxGen General Optical Model Prescription Generator

    Science.gov (United States)

    Sigrist, Norbert

    2012-01-01

    RxGen is a prescription generator for JPL's in-house optical modeling software package called MACOS (Modeling and Analysis for Controlled Optical Systems), which is an expert optical analysis software package focusing on modeling optics on dynamic structures, deformable optics, and controlled optics. The objectives of RxGen are to simplify and automate MACOS prescription generations, reducing errors associated with creating such optical prescriptions, and improving user efficiency without requiring MACOS proficiency. RxGen uses MATLAB (a high-level language and interactive environment developed by MathWorks) as the development and deployment platform, but RxGen can easily be ported to another optical modeling/analysis platform. Running RxGen within the modeling environment has the huge benefit that variations in optical models can be made an integral part of the modeling state. For instance, optical prescription parameters determined as external functional dependencies, optical variations by controlling the in-/exclusion of optical components like sub-systems, and/or controlling the state of all components. Combining the mentioned capabilities and flexibilities with RxGen's optical abstraction layer completely eliminates the hindering aspects for requiring proficiency in writing/editing MACOS prescriptions, allowing users to focus on the modeling aspects of optical systems, i.e., increasing productivity and efficiency. RxGen provides significant enhancements to MACOS and delivers a framework for fast prototyping as well as for developing very complex controlled optical systems.

  2. Americans' access to prescription drugs stabilizes, 2007-2010.

    Science.gov (United States)

    Boukus, Ellyn R; Carrier, Emily R

    2011-12-01

    Despite the weak economy and more people lacking health insurance, the proportion of Americans reporting problems affording prescription drugs remained level between 2007 and 2010, with more than one in eight going without a prescribed drug in 2010, according to a new national study from the Center for Studying Health System Change (HSC). While remaining stable overall, access to prescription drugs improved for working-age, uninsured people, likely reflecting a decline in visits to health care providers, as well as changes in the composition of the uninsured population. Likewise, elderly people eligible for both Medicare and Medicaid saw a sharp drop in prescription drug access problems. The most vulnerable people--the uninsured, those with low incomes, people in fair or poor health, and those with multiple chronic conditions--continued to face the most unmet prescription needs. For example, 48 percent of uninsured people in fair or poor health went without a prescription drug because of cost concerns in 2010, almost double the rate of insured people with the same reported health status.

  3. Drug prescription appropriateness in the elderly: an Italian study

    Science.gov (United States)

    Allegri, Nicola; Rossi, Federica; Del Signore, Federica; Bertazzoni, Paolo; Bellazzi, Roberto; Sandrini, Giorgio; Vecchi, Tomaso; Liccione, Davide; Pascale, Alessia; Govoni, Stefano

    2017-01-01

    Purpose Correct drug prescription in the elderly is a difficult task that requires careful survey of the current pharmacological therapies. In this article, we reviewed the drug prescriptions provided to 860 persons aged 65 years or over, residing in a small city of Lombardy, Italy. Methods Subjects were recruited from a local nursing home, the Pavia and Vigevano Neuropsychological Center for Alzheimer’s Disease, general practitioners’ offices, and the local University of the Third Age. For each patient, the amount of potentially inappropriate prescriptions (PIPs), sedative and anticholinergic load (SL and AL, respectively), and drug–drug interactions were evaluated. Results Widespread polypharmacy, giving rise to 10.06% of PIPs in the whole collection of prescriptions, was observed. In particular, PIPs mainly concern drugs acting at the central nervous system level, mostly benzodiazepines and antipsychotics. Moreover, approximately one-fourth of the subjects had an elevated SL and approximately one-tenth a high AL. Drug–drug interactions were frequent (266 requiring medical attention), up to five for each single patient. Of concern was the underuse of antidementia drugs: only 20 patients received a cholinesterase inhibitor or memantine, although 183 patients were potentially suitable for this treatment. Conclusion These results demonstrate the need to develop novel strategies aimed at improving the quality of drug prescription. PMID:28228653

  4. Misuse of Prescription Opioid Medication among Women: A Scoping Review.

    Science.gov (United States)

    Hemsing, Natalie; Greaves, Lorraine; Poole, Nancy; Schmidt, Rose

    2016-01-01

    Background. National data from Canada and the United States identify women to be at greater risk than men for the misuse of prescription opioid medications. Various sex- and gender-based factors and patient and physician practices may affect women's use and misuse of prescription opioid drugs. Objectives. To explore the particular risks, issues, and treatment considerations for prescription opioid misuse among women who experience chronic noncancer pain and trauma. Methods. A scoping review for articles published between January 1990 and May 2014 was conducted on sex- and gender-based risks and treatment considerations among women who experience chronic noncancer pain and trauma. Results. A total of 57 articles were identified. The present narrative review summarizes the specific risks for the misuse of prescription opioid medication among women who have experienced violence and trauma, Aboriginal women, adolescents and young women, older women, pregnant women, women of a sexual minority, and transwomen. Discussion. The majority of the literature is descriptive, with few studies that evaluate approaches and interventions to respond to the issue of chronic pain, trauma, and misuse of prescription opioids among women, particularly vulnerable subgroups of women. Conclusions. Trauma-informed and women-centred approaches that address women's vulnerabilities and complex needs require further attention.

  5. Misuse of Prescription Opioid Medication among Women: A Scoping Review

    Directory of Open Access Journals (Sweden)

    Natalie Hemsing

    2016-01-01

    Full Text Available Background. National data from Canada and the United States identify women to be at greater risk than men for the misuse of prescription opioid medications. Various sex- and gender-based factors and patient and physician practices may affect women’s use and misuse of prescription opioid drugs. Objectives. To explore the particular risks, issues, and treatment considerations for prescription opioid misuse among women who experience chronic noncancer pain and trauma. Methods. A scoping review for articles published between January 1990 and May 2014 was conducted on sex- and gender-based risks and treatment considerations among women who experience chronic noncancer pain and trauma. Results. A total of 57 articles were identified. The present narrative review summarizes the specific risks for the misuse of prescription opioid medication among women who have experienced violence and trauma, Aboriginal women, adolescents and young women, older women, pregnant women, women of a sexual minority, and transwomen. Discussion. The majority of the literature is descriptive, with few studies that evaluate approaches and interventions to respond to the issue of chronic pain, trauma, and misuse of prescription opioids among women, particularly vulnerable subgroups of women. Conclusions. Trauma-informed and women-centred approaches that address women’s vulnerabilities and complex needs require further attention.

  6. Urban Evolution: the Role of Water

    Science.gov (United States)

    The structure, function, and services of urban ecosystems evolve over time scales from seconds to centuries as Earth's population grows, infrastructure ages, and sociopolitical values alter them. In order to systematically study changes over time, the concept of "urban evolution...

  7. The problem of the near-earth asteroids encountering the earth

    Institute of Scientific and Technical Information of China (English)

    季江徽[1; 刘林[2

    2000-01-01

    The asteroids are the most important small bodies in the solar system, while the movement of the near-earth-asteroids (NEAs) is specially concerned by the world. The focus on these asteroids is that they encounter the earth. The orbital evolution of this kind of asteroid is studied by analyzing and comparing them; reasonable dynamical models and corresponding algorithm are given, and the formal numbered NEAs are calculated. The results of the minimal distance and the very close-approach time with the earth agree well with those announced by the Minor Planet Center (MFC).

  8. The problem of the near-earth asteroids encountering the earth

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The asteroids are the most important small bodies in the solar system, while the movement of the near-earth-asteroids (NEAs) is specially concerned by the world. The focus on these asteroids is that they encounter the earth. The orbital evolution of this kind of asteroid is studied by analyzing and comparing them; reasonable dynamical models and corresponding algorithm are given, and the formal numbered NEAs are calculated. The results of the minimal distance and the very close-approach time with the earth agree well with those announced by the Minor Planet Center (MPC).

  9. Socioeconomic Variations in Use of Prescription Medicines for COPD

    DEFF Research Database (Denmark)

    Jacobsen, Ramune; Ekholm, Ola; Rasmussen, Niels K.

    2016-01-01

    BACKGROUND: The purpose of this study was to examine socioeconomic variations in the use of prescription medicines among elderly subjects with COPD. METHODS: Data from the Danish national administrative registers were used. The study population included 1,365 individuals >60 y old residing...... in the Municipality of Copenhagen and diagnosed with COPD in a hospital setting in 2007. Logistic regression analysis was applied to examine the associations between the use of all prescription medicines for obstructive pulmonary diseases and the use of long-acting bronchodilators, in subject groups of different...... socioeconomic position. RESULTS: The study demonstrated that approximately 90% of subjects with COPD purchased at least one prescription medicine for obstructive pulmonary diseases, whereas approximately 50% purchased a long-acting bronchodilator. Medicine use did not vary according to educational status...

  10. Getting to the Root of High Prescription Drug Prices.

    Science.gov (United States)

    Waxman, Henry; Corr, Bill; Martin, Kristi; Duong, Sophia

    2017-07-01

    ISSUE: Historic increases in prescription drug prices and spending are contributing to unsustainable health care costs in the United States. There is widespread public support for elected officials to address the problem. GOAL: To document the drivers of high U.S. prescription drug prices and offer a broad range of feasible policy actions. METHODS: Interviews with experts and organizations engaged with prescription drug development and utilization, pricing, regulation, and clinical practice. Review of policy documents, proposals, and position statements from a variety of stakeholders. FINDINGS AND CONCLUSIONS: Congress and regulators can undertake a wide range of policy actions to begin to rebalance incentives for innovation and price competition, prioritize patient access and affordability, and maximize the availability of information to patients, providers, and payers.

  11. Ramp length/grade prescriptions for wheelchair dependent individuals.

    Science.gov (United States)

    Canale, I; Felici, F; Marchetti, M; Ricci, B

    1991-09-01

    The aim of this work was to provide well defined criteria for ramp construction for wheelchair dependent individuals (WDI). Force capability was measured in a large sample (140) of WDI, who presented different levels of motor impairment. Levels of impairment were established on the basis of the answers given in a questionnaire regarding the degree of self sufficiency at home as well as outside the home and active participation in sports events. Taking into account those WDI who exhibited at least a minimal level of self-sufficiency, the following prescriptions are indicated. For a 1 metre ramp length, allowable maximal incline 15%; up to 3 metre ramp length, maximal incline 10%. The reliability of such prescriptions was confirmed by having a test ramp traversed by 43 WDI. These values are suggested as confidence limits when faced with public building accommodations. Special prescriptions could be adopted for selected populations of WDI.

  12. Drug prescriptions in Danish out-of-hours primary care

    DEFF Research Database (Denmark)

    Christensen, Morten Bondo; Nørøxe, Karen Busk; Moth, Grete

    2016-01-01

    OBJECTIVE: General practitioners are the first point of contact in Danish out-of-hours (OOH) primary care. The large number of contacts implies that prescribing behaviour may have considerable impact on health-care expenditures and quality of care. The aim of this study was to examine...... the prevailing practices for medication prescription in Danish OOH with a particular focus on patient characteristics and contact type. DESIGN AND SETTING: A one-year population-based retrospective observational study was performed of all contacts to OOH primary care in the Central Denmark Region using registry...... data. MAIN OUTCOME MEASURES: Prescriptions were categorised according to Anatomical Therapeutic Chemical Classification (ATC) codes and stratified for patient age, gender and contact type (telephone consultation, clinic consultation or home visit). Prescription rates were calculated as number...

  13. Prescription drug monitoring programs in the United States of America

    Science.gov (United States)

    Félix, Sausan El Burai; Mack, Karin

    2015-01-01

    SYNOPSIS Since the late 1990s, the number of opioid analgesic overdose deaths has quadrupled in the United States of America (from 4 030 deaths in 1999 to 16 651 in 2010). The objectives of this article are to provide an overview of the problem of prescription drug overdose in the United States and to discuss actions that could help reduce the problem, with particular attention to the characteristics of prescription drug monitoring programs (PDMPs). These programs consist of state-level databases that monitor controlled substances. The information compiled in the databases is at the disposal of authorized persons (e.g., physicians, pharmacists, and other health-care providers) and may be used only for professional purposes. Suppliers can use such information to prevent interaction with other drugs or therapeutic duplication, or to identify drug-search behavior. Law enforcement agencies can use these programs to identify improper drug prescription or dispensing patterns, or drug diversion. PMID:25563153

  14. Utilisation of prescription and over-the-counter triptans

    DEFF Research Database (Denmark)

    Frisk, Pia; Kälvemark Sporrong, Sofia; Ljunggren, Gunnar

    2016-01-01

    triptans in Stockholm, Sweden. METHODS: Register data from 4759 patients dispensed triptans in 2014 were used to study documented diagnosis of migraine, concomitant acute and preventive treatment for migraine, and contraindications. Survey data from 49 patients purchasing OTC triptans in three pharmacies...... were used to capture physician-diagnosed migraine, concomitant acute and preventive treatment for migraine, a behaviour of combining or alternating between prescription and OTC triptans, and pharmacy counselling rates. RESULTS: Among the prescription triptan users, 52 % had a recorded diagnosis...... OTC and prescription triptans was rare. Concomitant acute treatment was reported in 53 % and preventive treatment was rare (4 %), despite high self-reported migraine frequencies. Some off-label use was detected, despite moderate to high counselling rates. CONCLUSION: Triptans are prescribed...

  15. EarthKAM

    Data.gov (United States)

    National Aeronautics and Space Administration — Sponsored by NASA, EarthKAM (Earth Knowledge Acquired by Middle School Students) is an educational outreach program allowing middle school students to take pictures...

  16. Earth on the Move.

    Science.gov (United States)

    Naturescope, 1987

    1987-01-01

    Provides background information on the layers of the earth, the relationship between changes on the surface of the earth and its insides, and plate tectonics. Teaching activities are included, with some containing reproducible worksheets and handouts to accompany them. (TW)

  17. NASA Earth Exchange (NEX)

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA Earth Exchange (NEX) represents a new platform for the Earth science community that provides a mechanism for scientific collaboration and knowledge sharing....

  18. Intelsat VII planning and evolution

    Science.gov (United States)

    Nadkarni, P.; Neyret, P.; Allnutt, J.; Chidambaram, T.

    This paper describes the evolution of the Intelsat VII concept from among a number of spacecraft concepts considered in the planning process. The considerations of greatest importance in this evolution are examined, including the compatibility with small earth stations, available digital services and circuit multiplication techniques, schedule considerations, launch vehicle considerations, and operational flexibility. The roles of demand analysis and of architecture selection in the development of the Intelsat VII concept are addressed.

  19. Drug prescription appropriateness in the elderly: an Italian study

    Directory of Open Access Journals (Sweden)

    Allegri N

    2017-02-01

    Full Text Available Nicola Allegri,1 Federica Rossi,2 Federica Del Signore,2 Paolo Bertazzoni,3 Roberto Bellazzi,4 Giorgio Sandrini,5 Tomaso Vecchi,1 Davide Liccione,1 Alessia Pascale,6 Stefano Govoni6 1Department of Brain and Behavioral Sciences, University of Pavia, 2Pavia and Vigevano Neuropsychological Center for Alzheimer’s Disease, 3”Bertazzoni” Pharmacy General Partnership, Vigevano, 4Nephrology and Dialysis Ward, Civil Hospital of Vigevano, 5C. Mondino National Institute of Neurology Foundation, IRCCS, 6Department of Drug Sciences, Section of pharmacology, University of Pavia, Pavia, Italy Purpose: Correct drug prescription in the elderly is a difficult task that requires careful survey of the current pharmacological therapies. In this article, we reviewed the drug prescriptions provided to 860 persons aged 65 years or over, residing in a small city of Lombardy, Italy.Methods: Subjects were recruited from a local nursing home, the Pavia and Vigevano Neuropsychological Center for Alzheimer’s Disease, general practitioners’ offices, and the local University of the Third Age. For each patient, the amount of potentially inappropriate prescriptions (PIPs, sedative and anticholinergic load (SL and AL, respectively, and drug–drug interactions were evaluated.Results: Widespread polypharmacy, giving rise to 10.06% of PIPs in the whole collection of prescriptions, was observed. In particular, PIPs mainly concern drugs acting at the central nervous system level, mostly benzodiazepines and antipsychotics. Moreover, approximately one-fourth of the subjects had an elevated SL and approximately one-tenth a high AL. Drug–drug interactions were frequent (266 requiring medical attention, up to five for each single patient. Of concern was the underuse of antidementia drugs: only 20 patients received a cholinesterase inhibitor or memantine, although 183 patients were potentially suitable for this treatment.Conclusion: These results demonstrate the need to develop

  20. Prescription opioid analgesics increase the risk of depression.

    Science.gov (United States)

    Scherrer, Jeffrey F; Svrakic, Dragan M; Freedland, Kenneth E; Chrusciel, Timothy; Balasubramanian, Sumitra; Bucholz, Kathleen K; Lawler, Elizabeth V; Lustman, Patrick J

    2014-03-01

    Prescription opioid analgesic use has quintupled recently. Evidence linking opioid use with depression emanates from animal models and studies of persons with co-occurring substance use and major depression. Little is known about depressogenic effects of opioid use in other populations. The purpose of this study was to determine whether prescription opioids are associated with increased risk of diagnosed depression. Retrospective cohort study, new user design. Medical record data from 49,770 US Department of Veterans Affairs (VA) health care system patients with no recent (24-month) history of opioid use or a diagnosis of depression in 1999 and 2000. Propensity scores were used to control for bias by indication, and the data were weighted to balance the distribution of covariates by duration of incident opioid exposure. Cox proportional hazard models with adjustment for painful conditions were used to estimate the association between duration of prescription opioid use and the subsequent risk of development of depression between 2001 and 2007. Of 49,770 patients who were prescribed an opioid analgesic, 91 % had a prescription for 180 days. Compared to patients whose prescription was for opioid prescription increased (HR = 1.25; 95 % CI: 1.05-1.46 for 90-180 days, and HR = 1.51; 95 % CI:1.31-1.74 for > 180 days). In this sample of veterans with no recent (24-month) history of depression or opioid analgesic use, the risk of development of depression increased as the duration of opioid analgesic exposure increased. The potential for depressogenic effect should be considered in risk-benefit discussions, and patients initiating opioid treatment should be monitored for development of depression.

  1. Potential misuse and inappropriate prescription practices involving opioid analgesics.

    Science.gov (United States)

    Liu, Ying; Logan, Joseph E; Paulozzi, Leonard J; Zhang, Kun; Jones, Christopher M

    2013-08-01

    Opioid misuse and abuse are growing concerns among the medical and public health communities. To examine the prevalence of indicators for potential opioid misuse in a large, commercially insured adult population. We adapted existing indicators developed by expert panels to include having overlapping opioid prescriptions, overlapping opioid and benzodiazepine prescriptions, long-acting/ extended release (LA/ER) opioids for acute pain,and high daily doses of opioids (>100 morphine milligram equivalents). These indicators were assessed among continuously enrolled individuals aged 18-64 years from the 2009 Truven Health MarketScan databases. Analyses were stratified by sex. We identified 3,391,599 eligible enrollees who received at least 1 opioid prescription. On average, enrollees obtained 3.3 opioid prescriptions, and the average annual days of supply was 47 days. Twice as many enrollees received opioid prescriptions for acute pain as for chronic pain. About a quarter of the enrollees had at least 1 indicator of either potential misuse by patients or inappropriate prescription practices by providers. About 15% of enrollees had high daily doses;7.8% had opioid overlap; and 7.9% had opioid and benzodiazepine overlap. Among those prescribed LA/ER opioids, 24.3% were treated for acute pain. Overlap indicators were more common among women. Our findings underscore the critical need to develop programs aimed at promoting appropriate use of opioids. Retrospective opioid utilization reviews similar to our analyses can potentially help managed care organizations and healthcare providers improve patient care and reduce the risk of adverse outcomes related to these medications.

  2. Prescription Opioid Analgesics Commonly Unused After Surgery: A Systematic Review.

    Science.gov (United States)

    Bicket, Mark C; Long, Jane J; Pronovost, Peter J; Alexander, G Caleb; Wu, Christopher L

    2017-08-02

    Prescription opioid analgesics play an important role in the treatment of postoperative pain; however, unused opioids may be diverted for nonmedical use and contribute to opioid-related injuries and deaths. To quantify how commonly postoperative prescription opioids are unused, why they remain unused, and what practices are followed regarding their storage and disposal. MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched from database inception to October 18, 2016, for studies describing opioid oversupply for adults after a surgical procedure. The primary outcome-opioid oversupply-was defined as the number of patients with either filled but unused opioid prescriptions or unfilled opioid prescriptions. Two reviewers independently screened studies for inclusion, extracted data, and assessed the study quality. Six eligible studies reported on a total of 810 unique patients (range, 30-250 patients) who underwent 7 different types of surgical procedures. Across the 6 studies, 67% to 92% of patients reported unused opioids. Of all the opioid tablets obtained by surgical patients, 42% to 71% went unused. Most patients stopped or used no opioids owing to adequate pain control, and 16% to 29% of patients reported opioid-induced adverse effects. In 2 studies examining storage safety, 73% to 77% of patients reported that their prescription opioids were not stored in locked containers. All studies reported low rates of anticipated or actual disposal, but no study reported US Food and Drug Administration-recommended disposal methods in more than 9% of patients. Postoperative prescription opioids often go unused, unlocked, and undisposed, suggesting an important reservoir of opioids contributing to nonmedical use of these products, which could cause injuries or even deaths.

  3. Regional variation in infant hypoallergenic formula prescriptions in Australia.

    Science.gov (United States)

    Mullins, Raymond J; Clark, Sunday; Camargo, Carlos A

    2010-03-01

    There is little information on the regional distribution of food allergy in Australia. We examined the influence of latitude (a marker of sunlight/vitamin D status) on food allergy, as measured by 2007 infant hypoallergenic formula (IHF) prescription rates in children ages 0-2 yrs. Data were compiled from the 52 statistical divisions in mainland Australia plus the island of Tasmania (n=53 observations). Data from the Australian Department of Health and Aging and the Australian Bureau of Statistics were analysed by statistical division. There was significant regional variability in hypoallergenic formula prescription rates (per 100,000 population/yr), with the highest rates in southern Australia (14,406) and the lowest in the north (721), compared with a national average of 4099. Geographical factors (decreasing latitude and increasing longitude) were associated with a higher rate of IHF prescriptions, such that rates were higher in southern vs. northern regions, and in eastern compared with western regions. Controlling for longitude, physician density and markers of socioeconomic status, southern latitudes were associated with higher hypoallergenic formulae prescription rates [beta, -147.98; 95% confidence interval (CI)=-281.83 to -14.14; p=0.03]. Controlling for latitude, physician density and markers of socioeconomic status, eastern longitudes were also associated with higher hypoallergenic formulae prescription rates (beta, 89.69; 95% CI=2.90-176.49; p=0.04). Among young children, hypoallergenic formula prescription rates are more common in the southern and eastern regions of Australia. These data provide support for a possible role of sun exposure/vitamin D status (amongst other potential factors) in the pathogenesis of food allergy.

  4. Electronic prescription as contributing factor for hospitalized patients' safety.

    Directory of Open Access Journals (Sweden)

    Gimenes FRE

    2006-03-01

    Full Text Available The following study was performed to identify factors related to medication errors in the computerized physician order entry and their advantages and disadvantages according to doctors, nursing team and administrative officers. It is a survey descriptive study carried out at three units of a Brazilian academic hospital in the southeast area. The study was divided in two phases. In the first phase, we analyzed a total of 1,349 prescriptions from general medical unit, surgical and orthopaedic wards during 30 days consecutively. A semi-structured instrument, elaborated by a group of researchers for the study proposals, was used. In the second phase, a semi-structured questionnaire was applied to the health professionals containing closed and open items approaching their opinion about the composition of electronic prescription, the advantages and disadvantages of them, and their suggestions for its improvement. Out of 1,349 prescriptions observed, 17.5% presented deletions, 25.0% medicines written manually and 17.0% of them were incomplete. Some of the advantages pointed by health professionals were its legibility (37.5%, little time spent when elaborating and emitting them (20.5% and the way they are a practical and organized (8%. The disadvantages pointed were repetition of previous prescriptions (34%, typing mistakes (17%, dependence on computers (11% and alterations made manually (7%. We conclude, this way, that the computerized prescription order entry represents a great progress among the strategies used to minimize medication errors caused by prescriptions badly formulated. However, it doesn't eradicate the possibility of medication error occurrences, needing some system modifications.

  5. Chemical evolution and the origin of life

    Science.gov (United States)

    Oro, J.

    1983-01-01

    A review is presented of recent advances made in the understanding of the formation of carbon compounds in the universe and the occurrence of processes of chemical evolution. Topics discussed include the principle of evolutionary continuity, evolution as a fundamental principle of the physical universe, the nuclear synthesis of biogenic elements, organic cosmochemistry and interstellar molecules, the solar nebula and the solar system in chemical evolution, the giant planets and Titan in chemical evolution, and comets and their interaction with the earth. Also examined are carbonaceous chondrites, environment of the primitive earth, energy sources available on the primitive earth, the synthesis of biochemical monomers and oligomers, the abiotic transcription of nucleotides, unified prebiotic and enzymatic mechanisms, phospholipids and membranes, and protobiological evolution.

  6. Research and Teaching About the Deep Earth

    Science.gov (United States)

    Williams, Michael L.; Mogk, David W.; McDaris, John

    2010-08-01

    Understanding the Deep Earth: Slabs, Drips, Plumes and More; Virtual Workshop, 17-19 February and 24-26 February 2010; Images and models of active faults, subducting plates, mantle drips, and rising plumes are spurring new excitement about deep-Earth processes and connections between Earth's internal systems and plate tectonics. The new results and the steady progress of Earthscope's USArray across the country are also providing a special opportunity to reach students and the general public. The pace of discoveries about the deep Earth is accelerating due to advances in experimental, modeling, and sensing technologies; new data processing capabilities; and installation of new networks, especially the EarthScope facility. EarthScope is an interdisciplinary program that combines geology and geophysics to study the structure and evolution of the North American continent. To explore the current state of deep-Earth science and ways in which it can be brought into the undergraduate classroom, 40 professors attended a virtual workshop given by On the Cutting Edge, a program that strives to improve undergraduate geoscience education through an integrated cooperative series of workshops and Web-based resources. The 6-day two-part workshop consisted of plenary talks, large and small group discussions, and development and review of new classroom and laboratory activities.

  7. An exercise prescription primer for people with depression.

    Science.gov (United States)

    Stanton, Robert; Happell, Brenda M

    2013-08-01

    A substantial body of evidence supports the value of exercise in the treatment of people with depression. The guidelines for exercise prescription, however, are limited, and based on those developed for healthy populations. This article explores the evidence for exercise in the treatment of depression and the role mental health nurses may play in the delivery of this information. A model of exercise prescription is put forward based on the available evidence and taking into account the challenges faced by mental health nurses and people with depression.

  8. Chiropractors' attitudes toward drug prescription rights: a narrative review.

    Science.gov (United States)

    Emary, Peter Charles; Stuber, Kent Jason

    2014-01-01

    The right to prescribe drugs remains a contentious issue within the chiropractic profession. Nevertheless, drug prescription by manual therapy providers is currently an important topic. Notably, physiotherapists in the United Kingdom were recently granted limited independent prescribing rights. Reports suggest that physiotherapists in Australia now want those same rights, and as such a review of chiropractors' general attitudes toward drug prescription is needed. To examine the literature concerning chiropractors' attitudes toward drug prescription rights and to compare the opinions of chiropractors currently licensed to prescribe medication with those in the profession who are not. This was a narrative review, consisting of a formal literature search and summary of included articles. Electronic databases searched included the Cumulative Index to Nursing and Allied Health Literature, PubMed, and the Index to Chiropractic Literature. Inclusion criteria consisted of prospective studies published in English in peer-reviewed journals. Studies were required to contain data on chiropractors' opinions toward medication prescription rights. Of 33 articles identified, a total of seven surveys were included in the review. Of these, there was a general split in opinion among chiropractors regarding the right to prescribe drugs in chiropractic practice. Those supportive of prescribing rights favoured a limited number of over-the-counter and/or prescription-based medications such as analgesics, anti-inflammatories, and muscle relaxants. When questioned on full prescribing rights, however, chiropractors were generally opposed. In jurisdictions where chiropractors are currently licensed to prescribe from a limited formulary, such as in Switzerland, the majority perceived this right as an advantage for the profession. Moreover, continuing education in pharmacology was viewed as a necessary component of this privilege. Based on the literature to date there is a general split in

  9. Prescription of fixed dose combination drugs for diarrhoea.

    Science.gov (United States)

    Chakrabarti, Amit

    2007-01-01

    Fixed-dose combinations (FDCs) of an antiprotozoal and an antibacterial, for treatment of diarrhoea, have been available in the Indian pharmaceutical market for about a decade. There is little evidence to substantiate this combination therapy. We evaluated 2,163 physician prescriptions for diarrhoea and found that 59 per cent of prescriptions were for FDCs. This is unethical because prescribing such combinations exposes a patient to higher risks of adverse drug reactions and also increases the chances of drug resistance. Physicians' prescribing practices in India are influenced by socioeconomic factors and the pharmaceutical industry's marketing techniques that include giving incentives to physicians to prescribe certain drugs.

  10. Justice implications of a proposed Medicare prescription drug policy.

    Science.gov (United States)

    Larkin, Heather

    2004-07-01

    Social justice is a core value to the mission of social work. Older people are among the most vulnerable populations for whom social workers are called on to advocate. Although Medicare prescription drug coverage has been a top legislative issue over the past few years, such a benefit expansion has yet to be implemented. This article examines the historical context of Medicare and reviews the proposals for prescription drug coverage, identifying the concerns raised. Literature critiquing the justice dimensions of health care for the elderly population is reviewed. Justice claims are identified and refined, and social justice theories are used in the analysis of the proposed policies.

  11. Evolution of stellar collision products in open clusters : II. A grid of low-mass collisions

    NARCIS (Netherlands)

    Glebbeek, E.; Pols, O.R.

    2008-01-01

    In a companion paper we studied the detailed evolution of stellar collision products that occurred in an N-body simulation of the old open cluster M 67 and compared our detailed models to simple prescriptions. In this paper we extend this work by studying the evolution of the collision products in o

  12. Galactic Cosmic Rays - Clouds Effect and Bifurcation Model of the Earth Global Climate. Part 2. Comparison of Theory with Experiment

    CERN Document Server

    Rusov, V; Vaschenko, V; Mihalys, O; Kosenko, S; Mavrodiev, S; Vachev, B

    2008-01-01

    The solution of the energy-balance model of the Earth's global climate proposed in Ref. [1] is compared with well-known experimental data on the palaeotemperature evolution of Earth's surface over past 420 kyr and 740 kyr obtained in the framework of Antarctic projects the EPICA Dome C and Vostok. The Solar-Earth mechanism of anomalous temperature jumps observed in the EPICA Dome C and Vostok experiments and its relation with the "order-chaos" transitions in convection evolution in the liquid Earth core responsible to the mechanism of the Earth magnetic field inversions was discussed. The stabilizing role of the slow nuclear burning on the boundary of the liquid and solid phases of the Earth's core (georeactor with power of 30 TW) for convection evolution in the liquid Earth's core and hence in the Earth's magnetic field evolution is pointed out.

  13. Chemical evolution and the preservation of organic compounds on Mars

    Science.gov (United States)

    Kanavarioti, Anastassia; Mancinelli, Rocco L.

    1989-01-01

    Several lines of evidence suggest that the environment on early Mars and early Earth were very similar. Since life is abundant on Earth, it seems likely that conditions on early Earth were conducive to chemical evolution and the origin of life. The similarity between early Mars and early Earth encourages the hypothesis that chemical evolution might have also occurred on Mars, but that decreasing temperatures and the loss of its atmosphere brought the evolution to a halt. The possibility of finding on Mars remnants of organic material dating back to this early clement period is addressed.

  14. A Research Report on the Prescription Rights of Chinese Nurses

    Institute of Scientific and Technical Information of China (English)

    Shi-Fan Han; Rui-Fang Zhu; Hui-Hui Han

    2015-01-01

    Objective:To explore the feasibility of the nurse’s prescription right in China,to develop the requirements for the qualification of the applicant for the prescription right of nurse,and to determine the content of certain prescriptions in the specific circumstances.Methods:Literature review on the relevant articles/material with the contents of the nurse’ s right of prescription home and abroad.Semi-structured depth interview method was used to interview 18 experts on whether the nurses can participate in the graded nursing decision and whether nurses with certain ability can make the decision.Using the self-made questionnaire "Nurses involved in graded nursing decision-recognition questionnaire",553 nurses completed questionnaires on willingness to nurse decision-making grading.Using the analytic hierarchy process,the 23 experts’ judgment on the main body of the graded nursing was rated.Using semi-structured depth interview method,17 experts were interviewed on the graded nursing quality assessment and training outline.The form of expert personal judgment and the "grading nursing qualification experts predict questionnaire" were used as a preliminary designing tool,32 experts were asked to predict the graded nursing quality.The relatively important factors that might promote implementation of right of Chinese nurse prescribing weights setting were obtained by analytic hierarchy process.Using Delphi method,2 rounds of consultation to 291 experts/times were performed,and determined its content on the fields of graded nursing decision,nurses’ job description,decision making nurse in graded nursing work process and related management system,decision-making main body of clinical nursing,nurse authority of prescription application qualification,clinical nurses,diabetes specialist nurses,tumor specialist nurses,nurses in emergency department,community nurses in certain circumstances writing prescription,and nursing undergraduate added with nurse authority of

  15. A Research Report on the Prescription Rights of Chinese Nurses☆

    Institute of Scientific and Technical Information of China (English)

    Shi-Fan Han; Rui-Fang Zhu; Hui-Hui Han

    2015-01-01

    Objective: To explore the feasibility of the nurse’ s prescription right in China, to develop the requirements for the qualification of the ap-plicant for the prescription right of nurse, and to determine the content of certain prescriptions in the specific circumstances. Methods: Literature review on the relevant articles/material with the contents of the nurse’ s right of prescription home and a-broad. Semi-structured depth interview method was used to interview 18 experts on whether the nurses can participate in the graded nursing decision and whether nurses with certain ability can make the decision. Using the self-made questionnaire“Nur-ses involved in graded nursing decision-recognition questionnaire”, 553 nurses completed questionnaires on willingness to nurse decision-making grading. Using the analytic hierarchy process, the 23 experts’ judgment on the main body of the graded nurs-ing was rated. Using semi-structured depth interview method, 17 experts were interviewed on the graded nursing quality assess-ment and training outline. The form of expert personal judgment and the“grading nursing qualification experts predict question-naire”were used as a preliminary designing tool, 32 experts were asked to predict the graded nursing quality. The relatively im-portant factors that might promote implementation of right of Chinese nurse prescribing weights setting were obtained by analytic hierarchy process. Using Delphi method, 2 rounds of consultation to 291 experts/times were performed, and determined its con-tent on the fields of graded nursing decision, nurses’ job description, decision making nurse in graded nursing work process and related management system, decision-making main body of clinical nursing, nurse authority of prescription application qualifi-cation, clinical nurses, diabetes specialist nurses, tumor specialist nurses, nurses in emergency department, community nurses in certain circumstances writing prescription, and nursing

  16. Capturing Near Earth Objects

    OpenAIRE

    Baoyin, Hexi; CHEN Yang; Li, Junfeng

    2011-01-01

    Recently, Near Earth Objects (NEOs) have been attracting great attention, and thousands of NEOs have been found to date. This paper examines the NEOs' orbital dynamics using the framework of an accurate solar system model and a Sun-Earth-NEO three-body system when the NEOs are close to Earth to search for NEOs with low-energy orbits. It is possible for such an NEO to be temporarily captured by Earth; its orbit would thereby be changed and it would become an Earth-orbiting object after a small...

  17. Finding the Age of the Earth by Physics or by Faith?

    Science.gov (United States)

    Brush, Stephen G.

    1982-01-01

    Refutes scientific creationists' arguments that the earth is less than 10,000 years old by presenting information related to the time scales for creation and evolution models, times from stellar distances, Kelvin's estimate of the earth's age, radioactive decay, radiometric dating, and the decay of the earth's magnetic field. (DC)

  18. Naturally occurring radionuclides and Earth sciences

    Directory of Open Access Journals (Sweden)

    G. Ferrara

    1997-06-01

    Full Text Available Naturally occurring radionuclides are used in Earth sciences for two fundamental purposes: age determination of rocks and minerals and studies of variation of the isotopic composition of radiogenic nuclides. The methodologies that are in use today allow us to determine ages spanning from the Earth's age to the late Quaternary. The variations of isotopic composition of radiogenic nuclides can be applied to problems of mantle evolution, magma genesis and characterization with respect to different geodynamic situations and can provide valuable information not obtainable by elemental geochemistry.

  19. 21 CFR 1306.05 - Manner of issuance of prescriptions.

    Science.gov (United States)

    2010-04-01

    ... not prepared in the form prescribed by DEA regulations. (b) An individual practitioner exempted from..., who fills a prescription not prepared in the form prescribed by DEA regulations. (g) An individual... not conform in all essential respects to the law and regulations. A corresponding liability rests upon...

  20. User-oriented Understanding of Descriptive, Proscriptive and Prescriptive Lexicography

    DEFF Research Database (Denmark)

    Bergenholtz, Henning

    2003-01-01

    There is much uncertainty and confusion as to the real differences between prescrip-tive and descriptive dictionaries. In general, the majority of existing accounts can be summarised as follows: Descriptive relates to the empirical basis; accordance between the empirical data and the dictionary i...